Showing posts with label Severe Weather Forecast. Show all posts
Showing posts with label Severe Weather Forecast. Show all posts

Friday, August 7, 2009

Severe Weather Potential - August 7 Update #3

Despite the hopes for convection before sunset, it does not appear likely as sunset is within an hour or two and there is not even a watch issued for potential development. Some cumulus is occurring in the warm sector, however, temperatures at 700hPa have increased to 14C directly over the most likely area for development. This is suppressing any chance of convection until at least after sundown across the area...

Thunderstorm development is still possible along the front as the low level jet increases slightly and we see the decoupling of the boundary layer. The tornadic threat with this development will be fairly minimal, with a large hail threat, and a more likely damaging wind threat across portions of southeast South Dakota and then across northern Iowa and southern Minnesota. An additional update is possible, but only if development can actually occur.

Once again Iowa has went and gone off to disappoint the severe weather lovers across the northern plains!

Severe Weather Potential - August 7 Update #2

Convective inhibition remains strong, however, confidence has increased that the inhibition will yield to convection during the late afternoon or evening hours across portions of the warm front in South Dakota and Iowa. Thunderstorms that do develop are likely to be supercellular with the threat for very large hail, damaging winds, and tornadoes given good low level shear and strong instability.

Just a short update... Expect to leave for a chase target in vicinity of Storm Lake, IA in approximately an hour. Storm initiation by 7 PM along the warm front in vicinity of prolonged strong low level convergence that is occurring in this area. Storms should follow this warm front, tapping into strong instability and good shear parameters leading to a continued tornado threat through 9 PM. Eventual evolution to a cluster or linear segments is expected beyond 10 PM with more of a damaging wind threat.

Severe Weather Potential - August 7 Update #1

Not much for changes in the going forecast or in the current analysis of things across the plains states. Watching clearing skies across the Dakotas and Nebraska, which should also work into western Iowa during the early afternoon hours. Warm front currently located along and just east of the Missouri River from South Dakota into western Iowa. This front should slowly move a bit northward, currently inhibited due to cold pool left from cloud cover and showers this morning. Strong instability and good inhibition is still in the forecast for the warm sector through this evening. A shortwave currently over eastern Colorado should move over the corner regions of SD/NE/MN/IA during the evening hours and should provide enough support for the formation of isolated thunderstorms.

Thunderstorms forming along the warm front would appear to be supercellular in nature during the evening hours, with the threat of very large hail, damaging winds, and the potential for a tornado given favorable storm motion. Storms should merge in the early nighttime hours, and begin more of a damaging wind threat across northern Iowa and southern Minnesota. This is confirmed with the latest SPC outlook upgrading the probabilities for damaging winds across this region...

Will watch the warm front evolution, as well as the 700hPa temperatures that will be inhibiting development until the Colorado shortwave makes its' way over during the evening hours.

Severe Weather Threat - August 7

Morning convection continues across southwest Iowa, with additional showers/thunderstorms spread throughout the state and spreading eastward at approximately 30-40 mph. These thunderstorms and showers should continue through the morning hours across much of the state, with cloud cover also remaining through 10 AM across the entire state. Look for a gradual decrease in coverage in both showers and cloud cover through the Noon hour and into the afternoon. Skies should begin to clear from west to east through the Noon hour as well, beginning to leave portions of western Iowa under warm and sunny skies by early afternoon. A warm front currently positioned south of the thunderstorm activity this morning should make its' way northward as the lee cyclone moves out of eastern Colorado and into the plains this afternoon. The warm front should become positioned parallel to I90 across southern Minnesota and likely through South Dakota, with a very warm/moist and unstable air mass to its' south.

Instability values should become quite high (3000-4000 j/kg) given surface temperatures near/above 90 degrees and dew point values well into the 60s and perhaps 70s along/south of the warm front. Strong surface convergence as well as theta-e should be taking place along the warm front, with aid from a subtle disturbance in the mid-levels also arriving during the evening hours across northwest Iowa. The combination of strong instability and continued convergence along the boundary may have the potential to break a cap that is likely to be in place throughout the afternoon south of the warm front. Temperatures at 700hPa are likely to be in the 11-13C range, with temperatures at 850hPa above 20C. Despite the warm temperatures aloft, models continue to indicate surface heating is enough to overcome the cap in areas that have this strong convergence along the warm front.

If the cap is overcome within the warm sector across northwest Iowa or South Dakota, expect rapid intensification of updrafts leading to large hail becoming a likely threat. Given strong shear values, especially for the late evening and early nighttime hours as the low level jet begins to aid the low level flow, a tornadic potential will exist with any development. Expect storms to begin to form into somewhat of a cluster or MCS after 10 PM and continue across the state, with perhaps an additional MCS moving out of the Dakotas and into MN/IA during the nighttime hours. An additional update is likely near the Noon hour, and once again through the afternoon and convective inhibition and the location of boundaries, etc. becomes more defined.

Storm Chasing Status: With a conditional threat, I will likely be sitting in the comfortable confines of home through the afternoon. However, with the threat likely evolving within an hours drive will be watching conditions closely. Current four county target area is Lyon and Osceola counties in northwest Iowa, and Nobles and Rock counties in southwest Minnesota.

Thursday, August 6, 2009

A Few Rounds of Storms

Sunday night did bring a few severe weather reports across the state, mainly of marginally severe hail around an inch in diameter and several wind gusts of 60 mph or so. The wind was strong enough to take down a few trees and power poles in a line roughly along Highway 30 from Sioux City towards Fort Dodge. We've held quiet since then, with temperatures still a little below normal for this time of year.

We'll be able to change the temperature aspect and finally feel some good summer heat and humidity for a few days for this weekend. This will also bring us the conditional chance of some thunderstorms during the late afternoon and overnight hours beginning tonight, and likely lasting through the weekend. At this time it is too conditional to really pinpoint any good chances of a round of thunderstorms, but rather good to mention that if thunderstorms do persist or develop into Iowa they are likely to have a chance of some large hail and damaging winds.

Our first chance will be across western Iowa tonight as a potential MCS will swing by the state coming out of the Dakotas. An additional round of storms may also be coming into northern Iowa by the early morning hours as the threat of an additional MCS seems possible. After these rounds of storms have a chance to move through, a good setup will be featured over portions of SD/MN/IA for severe weather. However, the warm air at the surface will also translate into the mid-levels and may keep us capped from thunderstorms. Sunday also appears to have a chance of thunderstorms, with the likelihood of an upgrade of the severe weather risks issued by the SPC in later outlooks.

While dodging the rounds of thunderstorms, enjoy the warm and humid air as temperature soar into the upper 80s and 90s and dew points rise into the upper 60s and even 70s creating the typical miserable summer feel. Additional updates may be given if warranted...

Thursday, July 23, 2009

Severe Weather - July 24

A strong cold front and associated upper level features will aid in thunderstorm development this afternoon across a majority of the state. Given current forecasts for shear, instability, and the strong support with the cold front it would appear that all modes of severe weather are likely across the risk area including isolated tornadoes, very large hail, and damaging winds.

Strong warm air advection should occur through the morning hours and into the late afternoon, suppressing any convection from occurring. As the cold front continues to dive southeast in the evening it should be able to overcome any inhibition that is in place ahead of it in the warm sector. Initial storm development between 6-8 PM should be supercellular in nature given strong bulk wind shear, and given strong veering winds near the surface a tornado or two is possible. Given the strong forcing along the cold front, thunderstorms should quickly develop along the entire front near sunset. This will promote more of a broken line mode of severe weather, with large hail and damaging winds becoming the main threat for the nighttime hours.


Additional updates are likely this afternoon when mesoscale discussions and eventual watch(es) area issued.

Monday, July 13, 2009

Severe Weather Potential - July 14

The potential for a significant severe weather event over portions of the central/northern plains is there for tomorrow, as potent surface features will be supported by strong upper air parameters. Two areas of interest are going to come into play, both of which have some very big question as to its' potential to produce significant severe weather. A lot of the questions may be answered tomorrow morning once the evolution of the MCS(s) from current severe/tornadic convection across SD/NE is known. An update during the overnight hours or during the early morning will hopefully give an idea as to which area of concern is greatest.

The most favorable target will likely be along a reinforced warm front or outflow boundary following tonights' convection that will setup across southeast Nebraska, southwest Iowa and across northern/western Missouri. Strong heating and moisture return will be in place for this area, providing extreme instability and likely strong lift. Upper air features better align with this area of instability and lift, aided by a shortwave that would likely aid in development. As with the case with most late season events with such extreme parameters in place is the capping concerns... Temperatures at 700hPa near the 12C mark will likely cap thing well into the afternoon, however, there is support with the models indicating that this capping inversion will be broken before 00z. A target in this area could come with some significant rewards, or you could end up with nice blue skies as the cap holds.

Another target area will be further north along the cold front which is forecasted to move into western Minnesota and near the SD/NE/IA/MN corners and into eastern Nebraska. Capping will be less of a concern here with a strong mechanism for storm development (cold front) and 700hPa temperatures less than 12C. Development is likely by the evening hours along the cold front throughout western Minnesota and into SD/IA/NE. The problem with the setup here arises with the displacement of instability and shear parameters, with strong instability present along/ahead of the cold front (especially at low levels), but the best shear further ahead of the front. Any development just ahead of the cold front may be able to tap into both instability and shear, thus able to put on a show... This would rely on any outflow boundaries from morning convection...

Additional updates likely within the next 8-12 hours... I will likely favor the secondary target area as it is quite local.

Wednesday, July 8, 2009

Severe Weather Potential - July 9

A complicated forecast is in the works for the next 36 hours, and perhaps even longer, for Iowa and adjacent areas. A strong wave will initiate thunderstorms this afternoon across the western Dakotas and areas of Montana/Wyoming. These storms should develop into a large MCS, possible derecho, during the evening and overnight hours traversing the Dakotas and moving into western Minnesota by sunrise on Thursday. This MCS will likely be making a right turn throughout the night as the low level jet veers, making the projected path perhaps into northern Iowa between 6-10 AM tomorrow. While the severe weather threat would seem minimal, gusty winds nearing severe criteria is a definite possibility.

As this MCS clears, a stable layer will be left over and likely inhibit additional development until the later afternoon hours. With a cold front and strong disturbance coordinate to create sufficient lift to break and inhibition that will be present across northern Iowa and southern Minnesota. With wind fields increasing in strength throughout the lower and mid-levels, expect deep layer shear to be sufficient for supercells as the initial storm mode with damaging winds, large hail, and isoalted tornadoes all being possible. However, with time and more forcing along the cold front it would appear that the growth of another MCS is likely, yielding a damaging wind threat across the central portions of the state. More details into the forecast will be clear tomorrow morning when the extent of the morning MCS is known... Expect an additional update late tonight and early tomorrow as to the possibilities of severe weather across portions of Iowa.

Tuesday, July 7, 2009

Severe Weather Potential - July 7

A trough of low pressure and possible weak low pressure center should be located over central South Dakota this afternoon. A stationary boundary should extend eastward from this low over parts of eastern South Dakota, southern Minnesota and northern Iowa. This boundary and low pressure center should be the focus for thunderstorm development this afternoon and through the overnight hours, with the potential for severe weather.

While current forecasts indicate that thunderstorms will be more likely to develop in South Dakota, and move into MN/IA/NE during the evening/overnight hours there is potential for development along the frontal boundary during the afternoon and this is supported by a few high-resolution models this morning. Any thunderstorms that do develop this afternoon across the northern plains of SD/NE/IA/MN may be capable of damaging wind gusts and large hail, as well as an associated weak tornado or landspout threat. Storms are likely to congeal into clusters as the evening progresses and move southeastward with time with more of a damaging wind threat through the overnight hours into IA/MN and perhaps northeastern Nebraska.

Additional updates are possible this afternoon as storms develop or initiation becomes more defined...

Sunday, June 21, 2009

Severe Weather Potential - June 21

More of a summer-like pattern has pushed into the central plains, with a weak ridge trying to work into the plains states. This has left us with southwest flow aloft through the state of Iowa, and with a low pressure system working off of the high plains and into Nebraska this morning will set us up for a round of severe weather this afternoon. This low pressure system should work into the four corners area of NE/SD/IA/MN by mid-afternoon, with a well defined warm front to its' east/southeast and a trough of lower pressure to its' south/southwest. Along and south of the warm front should have clear skies through the afternoon, with strong heating near 90 and dew points surging into the lower 70s across the area. This should provide us with moderate to strong instability across the state, and with little in the way of inhibition it would likely to see storm initiation fairly early in the afternoon in areas that clear and develop this instability.

Given decent southeasterly flow within the warm sector, low level shear should be sufficient to warrant a tornadic risk. Combined with the very low LCL levels thanks to good heating and moisture present, this tornadic risk seems to be fairly significant. Storms that do develop and move east/southeast nearly parallel to the warm front would have favorable conditions to be tornadic. Thus, would expect areas of northern Iowa, and eastern Iowa where the warm front is more southeast oriented to see the greatest risk of severe weather including tornadoes.

It is Father's Day, thus a lot of people likely enjoying the day outside. It will be important to pay attention to the weather this afternoon due to the risk of severe weather, specifically tornadoes. An additional update near Noon is expected, this will be a brief update in regards to any change in potential.

Friday, June 19, 2009

Severe Weather Threat - June 19

While yesterday turned out to be another cap bust in Iowa that makes all those out-of-state chasers absolutely hate chasing in Iowa, today will definitely not be the same. Must cooler temperatures just above the surface in the lower levels will provide much less of a capping inversion, and with a must stronger wave in the mid-levels combined with significantly more convergence at the lower levels as well with a cold front moving southeastward. All of this will provide the southeast half of the state to see numerous thunderstorms, many of which may be severe with damaging winds and large hail.

Be sure to pay attention to the latest weather information via TV/Radio as thunderstorms near your area. While the risk of tornadoes is forecasted, it would appear that surface winds quickly turning southwesterly will decrease the low level shear dramatically, thus inhibiting the strong low level shear that was expected to aid in tornadic development.

Thursday, June 18, 2009

Significant Severe Weather - June 18

The updated SPC Day 1 outlook will continue the moderate risk of severe weather across much of northern Iowa and southern Minnesota. There is a significant risk of damaging winds, very large hail, and tornadoes across the area today. In fact, the updated outlook has increased the probability of tornadoes over northern Iowa and southern Minnesota. The morning thunderstorms will actually help increase the risk of tornadoes this afternoon/evening as the outflow boundary left in its' wake will interact with the warm front to create substantial low level shear. This would appear to once again be a very dangerous and life threatening situation over areas of the plains states today.

I will be chasing today across northwest Iowa, this blog will have the latest updates as I can provide them. As we near the afternoon initiation you may be able to view live video from my vehicle as well as track my location via the Iowa Chaser LIVE Chase Page.

Next update in regards to afternoon chasing and severe weather is expected in the early afternoon hours.

Wednesday, June 17, 2009

Severe Weather Update #1 - June 17

Severe and now tornadic thunderstorms are ongoing with the stronger warm front located along the Kansas/Nebraska border. Additional storms are likely as we continue through the afternoon and eventually congeal into more of a cluster or MCS of storms moving into west-central and southwest Iowa.

The other area of concern for severe weather, including tornadoes, will be over northwest/north-central Iowa where a convergent low level boundary associated with a weak low pressure system over South Dakota may trigger thunderstorms this afternoon/evening. Latest analysis indicates this wind shift is becoming very defined with strong instability along and east of the boundary. Effective wind shear values above 40 kts will support supercells when initiation occurs, and likely support tornadic storms through the evening hours.

I plan on chasing any development along this wind shift and weak boundary in northwest Iowa, thus stay tuned for additional updates!

Severe Weather Potential - June 17

The potential is there for significant severe weather across the western half of Iowa this afternoon and into the overnight hours. All modes of severe weather appear possible, including damaging winds, very large hail, and tornadoes. There are two areas of concern for severe weather today, both of which cover western Iowa...

The first and most likely concern will be over much of western Iowa, and likely be during the late evening or overnight hours. This severe weather threat will likely be for damaging winds and large hail, although a risk of tornadoes will exist, a more linear nature of thunderstorms may be expected. These thunderstorms will evolve from central Nebraska this afternoon as they initiate due to a shortwave and frontal system interaction. As the thunderstorms continue to evolve eastward they are likely to congeal into a more linear MCS capable of large hail and damaging winds as they enter into western Iowa.

Another threat for severe weather will exist during the afternoon/evening hours over mainly northwest Iowa, as well as southwest Minnesota. Similar to yesterday afternoon over South Dakota, a weak low pressure system in conjunction with a trough of low pressure and low level convergence may lead to thunderstorm development along a weak wind shift line. With even higher temperatures and dew points this afternoon yielding even higher instability amounts this will come as no surprise to see even stronger supercells off of this setup. These storms will be capable of all modes of severe weather through the evening hours, but similar to yesterday they should begin to weaken after sunset.

Additional updates are likely this afternoon as the severe weather threat evolves, I am watching the potential across northwest Iowa for the tornadic supercells similar to yesterday...

Tuesday, June 16, 2009

Severe Weather Threat - June 16

While some thunderstorms move across parts of central/eastern Iowa this morning, and some lingering showers/cloud cover continue across western Iowa, we are likely to see clearing skies and an increased chance of thunderstorms once again this afternoon/evening and potentially into the overnight hours. Temperatures not only today, but through the remainder of the week are likely to rebound nicely after morning convection and/or cloud cover. Highs into the 80s and 90s over the state are likely through Thursday...

A weak surface low is positioned across central South Dakota this morning, and is likely to only move slightly as we continue into the afternoon hours. Two troughs of low pressure are likely to extend from this low pressure system and create a moderately unstable warm sector for this afternoon across eastern Nebraska, eastern South Dakota, western Iowa and other adjacent areas. Moderately instability combined with a weakly capped environment should create ample development by the afternoon hours along both troughs in SD/NE and perhaps across Minnesota and extreme northern Iowa. While moderate bulk shear is present across the entire warm sector, directional shear appears to be limited over SD/NE/MN/IA where development is likely. Thus it would appear as if the main threats of severe weather will be for large hail and damaging winds with the strongest and more organized storm clusters this afternoon. Additional update are possible if the severe weather threat warrants...

The severe weather threat will likely continue for the northern plains on Wednesday, and continue through Friday. Both Wednesday and Thursday have warm fronts that will likely be positioned across Iowa or just south of the state warranting the risk for severe weather. Thursday will also have a cold front finally pushing eastward over the plains states with an increased risk of severe weather; a similar threat exists on Friday. Additional updates on these risks as the week continues.

Sunday, June 7, 2009

Severe Weather - June 7

Once again a warm front will be draped across the plains states, from northern Kansas through southeast Nebraska and then across parts of southern/central Iowa. Areas along and south of this front are likely to see temperatures near/above 80 degrees this afternoon with surface dew points into the lower 60s. This will provide moderate to strong instability, and combined with ~40 knots of 0-3km wind shear across this sames area of eastern KS/NE and southern IA will provide an environment for supercells. The potential for supercells will be enhanced by an increasing low level jet across the plains states, and any outflow boundaries that may be situated in this warm sector. Thunderstorms should develop along these outflow boundaries in vicinity of the warm front, indicating likely areas of initiation to northeast Kansas, southeast Nebraska and potentially into southwest Iowa. Thunderstorms in the early stages are likely to contain very large hail and the potential for tornadoes; as storms continue into the overnight we could see one or more clusters of storms. These clusters are likely to continue the threat of large hail and especially damaging winds across the remainder of southern/eastern Iowa.

Additional updates are possible this afternoon as storms begin to develop...

Saturday, June 6, 2009

Severe Weather - June 6

Overnight convection associated with an MCS has continued to move through the state of Iowa this morning, and another cluster of precipitation is also moving across extreme northeast Nebraska and eastern South Dakota as well. This precipitation and its' evolution was a big question mark as to how it would affect the forecast for today's severe weather as it would influence the location of the warm front. It would appear that a cold pool has setup across parts of southeast South Dakota and adjacent areas of Minnesota and Iowa, however, areas behind this convection are already clearing indicating that there may only be a minimal effect from this mornings' precipitation across much of eastern Nebraska and western Iowa. In fact, elevated instability is already showing up across much of eastern Nebraska where clearing is already occurring.

Current SPC forecasts still indicate that they do not expect the front to have much of a northward surge at all today, leaving the primary focus for severe weather across southeast Nebraska and extreme northern Kansas. Once storms fire over that region this evening, they would then propagate northeastward along the warm front into western Iowa with the threats of damaging winds and large hail. This may be the more likely scenario, however, an eye will likely be kept on this front and its' northward progression throughout the day.

Severe weather will definitely be a possibility for areas south of a Kearney, NE to Sioux City, IA to Fort Dodge, IA line. All modes of severe weather would appear likely south of this line, including the threat of tornadoes in both discrete supercells and even in a more linear segments given strong shear values across the region. Once again however if the warm front is able to surge north across any portion of Nebraska/Iowa the threat of severe weather may move northward... Additional updates this afternoon may address this if it does indeed look to be occurring.

With prior plans in Vermillion, SD until ~7 PM I don't see any chasing occurring today unless the front can surge well north of its' current forecast. Tomorrow may be another chance with those details later tonight...

Friday, June 5, 2009

Severe Weekend Weather!

One of the more impressive setups for severe weather will take place beginning today and continue through the weekend for the northern/central Plains states. A broad western trough has finally moved into position to create southwesterly flow across the high plains today, and will make progress eastward over the next two days to continue this southwest flow into the central US. Today's severe weather threat will be held to the high plains due to meager moisture in place, and the more favorable upper level support is located across the high plains as well. Today's area of interest will include western Nebraska, northeast Colorado, and nearby adjacent areas including eastern Wyoming. The main threats with today's storms in the high plains will be very large hail and tornadoes given a strengthening low-level jet in the evening hours.

Tomorrow (Saturday) the lee cyclone begins to move off of the high plains and further east into Nebraska, with the aid of strong southerly jets just above the surface and an open Gulf of Mexico even at the surface we will see strong moisture return through the day and into the overnight. Moisture return will likely make it to near 60 or just above by Saturday evening, leading to only moderate instability across Nebraska and into western Iowa along/south of a warm front. The warm front location is somewhat in question, although this mornings' models locate this front from near Lincoln, NE to Clear Lake, IA and eastward towards Dubuque, IA. A dryline also situates itself southward from the low in central Nebraska, leading to other favorable areas for severe weather along this dryline through central Kansas. Shear values are favorable throughout this region, and initiation of storms appears likely nearest to the low pressure system in Nebraska and along/north of the warm front in NE/IA. Further south along the dryline could have explosive development if 700hPa temperatures well above 10C do not cap the convection. Storms that do develop and remain somewhat discrete will be supercellular in nature capable of large hail, damaging winds, and tornadoes. The more likely scenario will be for the storms to develop near the surface low and near the warm front, these storms will be capable of large hail/damaging winds. Given moderate moisture, storms may become surface based and definitely become capable of tornadoes as storms move along the warm front. An additional update on tomorrow may be posted later today if necessary...

Sunday is another day that holds very high potential for severe weather, given deeper and more sufficient moisture return south of the warm front that is once again expected to be draped from northern Nebraska through central/northern Iowa (Norfolk, NE to Sioux City, and near Clear Lake). While the warm front doesn't appear as defined on Sunday, likely due to convection debris/cloud cover from Saturday night, sufficient instability and lift would appear strong enough to erode the capping inversion that is once again present south of the warm front (10-12C 700 hPa temperatures). Once again storms should develop near the low pressure and near the warm front, capable of large hail/damaging winds/tornadoes given increasing shear values throughout the evening. As storms continue to develop near the low and further south along the dryline, it would appear that an MCS will once again develop and push east/northeast through Iowa capable of hail/winds. An update will be posted for Sunday either tonight/early tomorrow or potentially early Sunday.

I'm currently scheduled to photograph a wedding in Vermillion, SD on Saturday afternoon and early evening. Meaning I'm already in position for the potential on Saturday along the warm front and perhaps in position for Sunday in northeast Nebraska given an overnight stay. All of my chase gear will be with me needless to say...

Monday, June 1, 2009

Severe Weather Forecast - June 1

Welcome to June! Our first day will be welcomed with a warm front draped across the state, which will trigger afternoon/evening thunderstorms capable of large hail, damaging winds and even a tornado or two! After the cold front slid through parts of the state last night, the front will continue to slowly progress southward and may even stall out somewhat this afternoon with the warming air mass to its' south. Current forecasts indicate it to position itself near the I-80 corridor by 7 PM tonight.

For those that are along this front, just south/north of the boundary are going to be in a favorable position for thunderstorms this afternoon. Today is one of those warm front days where the instability is all south of the front, but the shear is mainly north. Which means any storms that are able to ride along the boundary to get the best of both sides will be the strongest and most organized of the day, and will be the most likely storms capable of a tornado or two. With flow otherwise parallel to the front, expect storms to eventually congeal into broken lines or clusters capable of large hail and a few wind gusts. Once again expect the thunderstorms to persist into the early nighttime hours with some severe potential.

As the low level jet increases tonight, this will push some elevated instability north of the boundary, likely over much of Iowa. This will also bring the chance for at least elevated storms capable of some large hail given this strong overrunning of moisture across the front in southern/central Iowa. These storms will likely be in clusters or broken lines given the better shear values that are north of the front.

I begin my part-time job this morning, thus am not expecting to chase today along the stalled boundary. Although if any significant changes in the tornado chances occur by early this afternoon I may have to take the quick dive south into the favorable chase area... Another update is possible early this afternoon...

Sunday, May 31, 2009

Severe Weather Update #2 - May 31

A few severe thunderstorms, and even one tornado warning, was issued this evening across southeast Nebraska and southeast South Dakota. Warnings are still ongoing across parts of central/eastern Nebraska along the cold front, however, these storms are only capable of large hail at the moment. Other storms along the cold front in southern South Dakota and Minnesota are only capable of heavy rains and maybe some small hail currently. Although the low level jet should begin to ramp up, these storms do not look like they will be well-above severe limits tonight.

Enjoy the rain, maybe some small hail, and otherwise rumbles of thunder overnight...

Another update is likely early tomorrow with a quick discussion about the warm front across the central/southern thirds of the state tomorrow.