Much Quieter

After a busy weekend for portions of the state we have set into a much quieter pattern for the remainder of the week, with mostly sunny skies and temperatures in the upper 80s and lower 90s across the state. A weak ridge to zonal flow will be in place across much of the western two-thirds of the US through the end of the week. This is what will be leaving Iowa and much of the plains under sunny skies with warm temperatures. As we work into the weekend a trough enters the flow and will begin to affect the northern plains late Friday and continue through Monday. It is still too early to tell the thunderstorm threat, and specifically the severe weather threat with this disturbance.

Enjoy what seems to be the first full week of summer-like temperatures and conditions. Beyond our weekend disturbance long-range forecast models once again bring the jet stream well north and leave the plains in a weak ridge indicative of warm temperatures and mostly sunny afternoons.

A quick look back at Sunday's long lived supercell that progressed along highway 20 throughout the state, the Des Moines NWS has a nice page that shows a radar loop with storm reports. There is also a few pictures that were provided by the Fort Dodge Amateur Radio Association, you can check them out on the NWS page and below:

NWS Des Moines - August 9 Supercell Page

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...

Cool & Calm July

Iowa has been both on the cool and calm side of the weather for the month of July despite a few events that have hit some parts of the state hard, including a few tornadoes and some very damaging hail across northeast Iowa last Friday. A rough and quick look at the mean temperatures over the month of July indicates that it is likely to be the coolest since 1992. For example, Estherville has a mean temperatures thus far of 66.8 degrees, which is second coolest since 1951!

The final day of the month looks to be just at, or just below normal for the state. We'll also get a good chance of some thunderstorms for the end of the month across at least the western half of the state. The severe weather threat appears minimal at the moment, but some small hail and gusty winds is not out of the question for the western third of the state. An update may be necessary if the potential for severe weather tomorrow night does increase...

We'll clear off and be near or just below normal for high temperatures once again through next week; low temperatures will be just below normal. A chance of thunderstorms and showers will work its' way back into the forecast for mid-week, otherwise it appears dry through the first week of August. The long range forecasts do indicate the possibility of a good ridge building into the central US through the first weeks of August which may finally lead to some above normal temperatures!

A Quick Recap

Busy days ongoing for me has created a good lack of updates on my part. Just to review back to July 14, the severe weather threat did materialize, although much weaker than initially thought due to only convection along the front firing during the evening hours. Did manage to punch through a severe warned cell between Wallingford and Ringsted on the way back from a playoff baseball game. This cell didn't really back much punch in regards to wind, and no hail was found. A weakly photogenic shelf cloud was noted, but not captured...

After the cold front passed through the state we were left with some below average temperatures that have continued into tonight. Current temperatures early this morning range from the mid 50s to the upper 40s! High temperatures for Friday should range from the upper 60s to the mid 70s across the state from northeast to southwest; lows overnight will drop into the upper 40s to mid 50s across the state once again. The weekend will stay dry with highs in the upper 60s to mid 70s from east to west on Saturday, then from mid 70s to mid 80s by Sunday. Low to mid 50s for Saturday night temperatures, and mid 50s to lower 60s from east to west for lows on Sunday night.

We'll return to chances of thunderstorms and showers for the work week, with the best chances on Monday night in the west; Tuesday and Tuesday night for the central and eastern thirds, and the potential for a lingering shower or storm in the east on Wednesday. High temperatures in the upper 70s to mid 80s from east to west for the first half of the work week; with lows in the upper 50s to mid 60s. Look for an update on these chances of thunderstorms come early next week!

Severe Weather Recap - July 7

A cluster of thunderstorms developed in eastern South Dakota during the afternoon hours yesterday, and entered into northwest Iowa during the evening hours. These clusters of storms were at times severe warned with the potential for both damaging winds and large hail, estimated 60 mph winds were reported and hail up to 1.5" in diameter also occurred. The severe weather was intermittent at best, with little in the way of damage reported.

I ventured outside of home for a short while as the leading edge of what was a bow echo entered the state in northern Emmet county. Upon arriving outside of Wallingford I did capture very brief video of a gustnado on this leading edge. I estimate the location of this gustnado near Dolliver, IA given its' distance away from me at that time. An otherwise uneventful night as gusty winds and heavy rains were all that occurred...

I will try to get a vidcap of the gustnado up at a later time... Along with a few panoramic images of the shelf as it entered Emmet county.

Severe Weather Potential - June 24

Quick update from the road today as I am returning from a trip to Ames to visit a few friends. Thunderstorms were widespread yesterday as they continued to move in from NE/SD during the early afternoon hours. Although a few tornado warnings were issued, these tornado warnings were for small vorticies that were confined within the larger line of storms as it moved across the state. No reports were confirmed of a tornado in the state yesterday, but wind damage was widespread through nearly the entire state with wind gusts nearing 80 mph in a few of the stronger storms during the afternoon.

Today's severe weather threat would appear to exist during mainly the late evening and overnight hours as storms once again move out of SD/NE and into western Iowa. A few rogue thunderstorms may develop in localized areas of convergence this evening and have the potential for damaging winds, hail and an isolated tornado. Otherwise it is likely that an MCS will form over eastern SD and continue east/southeast into northwestern Iowa during the early overnight hours. This MCS will likely contain damaging winds and perhaps some small hail as it moves across the state.

Welcome Summer...

Apparently summer did not want to show up until it was officially ready, with Sunday being the first day of summer the state sure has heated up since. High temperatures yesterday ranged from the lower to mid 90s across the entire state, with plenty of moisture across a majority of the state to make it feel like temperatures were close to triple digits. Today will be similar, with highs actually getting a few degrees higher than yesterday in most locations. With high continuing in the lower to mid 90s, and even more moisture present today, heat indices will range across the lower 100s. This has prompted a majority of the state to be put under a heat advisory for this afternoons' heat.

Thunderstorms are a possibility across the state tonight and tomorrow, with a chance of a few storms even being near or above severe limits overnight tonight across western and central Iowa. These thunderstorms should be fairly isolated in nature, with marginal hail and damaging winds as the main threats. Temperatures will cool some on Wednesday with the passing of this system, but temperatures should still remain in the 80s across the state. Those temperatures in the 80s should continue through the remainder of the week, with continued high moisture leading to the warm/sticky days and enjoyable nights.

Iowa Upsets Chasers

Once again the state of Iowa has upset the chasing community with its' lack of cooperation over the past two days. Two straight days of moderate risk, and two straight days of utter disappointment for any storm chaser that was in the state. Both setups featured their own caveats, and both featured the opportunities for greatness, but both days have their caveats win out with no tornado reports and perhaps the highlight of a shelf cloud and some impressive winds this afternoon in southeast Iowa.

Thursday's setup featured a warm front which pushed well north of the state, leaving the state under a heavy capping inhibition between 850 hPa and 700 hPa. With no warm front to help trigger thunderstorms, only a weak remnant outflow boundary had an opportunity for greatness. Although it tried with several cumulus fields attempting to bubble up through the capping inversion, none would ever succeed. Thus, tack a point up for capping inversions with 12C temperatures at 700 hPa over Iowa as a bad chase day.

Today's (Friday) setup finally featured a strong trigger for convection as a cold front moved through the state, and an outflow boundary once again was expected to allow low level winds to remain southeasterly and aid in low level shear. The disappointment would come with winds remaining southwesterly ahead of the cold front, and the lack of a capping inversion allowing the whole cold front to be socked in with showers/storms from Noon onward. At least there were thunderstorms, albeit outflow dominant, that would let you chase something! Wind reports were consistent with at least three separate thunderstorms today, with winds ranging from 60-85 mph across eastern Iowa. Still, a day that would have offered tornado potential for the state would be ruined by a cold front with little inhibition and the lack of cooperation of the surface winds.

If anything can be learned from the past two days, trust instincts that a 12-13C temperature at 700hPa and no strong convergence in the lower levels will lead to nothing but struggling cumulus or blue skies. And, when a cold front comes into the state then you need the 12C temperature at 700hPa along with some southeast if not at least south winds to provide low level shear.

Here's to the hope that the more summer-like thunderstorms can provide some punch for the state with at least some great lightning and supercellular structure!!

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.

Warming Weekend

After below normal temperatures and an end of the week that was both cool and wet we will begin a weekend that will start us on a warming trend! Rainfall totals across the state appeared heaviest across western Iowa where just over an inch fell in areas such as Sioux City and LeMars. Other areas of the state, especially the southeast, did not see nearly as much with only a few hundredths to a few tenths in the heaviest areas. Expect a few lingering showers over central and eastern Iowa tonight, and mainly cloudy skies over those same areas while parts of western Iowa begins to see some clearing skies.

Lows overnight tonight from near 50 in the northwest to near 60 in the southeast. Partly cloudy skies will prevail for Saturday, and with the sunshine we'll see highs in the mid 70s throughout the entire state. Saturday night will remain partly cloudy across the state, with increasing clouds over the west as we near sunrise on Sunday. Low temperatures will range from the lower to mid 50s from northeast to southwest. A weak frontal system will approach the state from the southwest on Sunday, bringing in more chances of showers and an isolated thunderstorm over the southwest half of the state on Sunday and Sunday evening. Highs on Sunday should be fairly consistent across the state near the mid 70s; with overnight lows in the mid to upper 50s from northeast to south. Our frontal system stalls out and begins to become diffuse which will decrease our chances of showers overnight on Sunday.

In the long range, it would appear that mainly zonal flow with embedded shortwaves will prevail over the plains states through the week. This will bring us off and on showers/thunderstorms throughout the week. Some slight ridging is expected to begin towards next weekend, with this expect an increase in temperatures as we near the upper 80s and finally the 90s across parts of Iowa. More details on this true southern warmth in next weeks' forecast updates.

TWISTEX & Other Chasers

Today was forecasted to be another potentially significant day of severe weather with an increased tornado potential across the plains states. Unfortunately for all of the groups out there that are doing research, from my TWISTEX buddies, to VORTEX2, and to all of the other chasers out there, today once again turned to be a big disappointment from a tornadoes standpoint.

The tornado reports today came across eastern Kansas during the early afternoon storms that were likely triggered and aided by the morning MCS. Other reports came across the high plains of Colorado where little risk was expected, and even a stray report in Nebraska that was a very brief and likely a landspout. Sunday was expected to be a strong day for thunderstorms and tornado potential, while the thunderstorm aspect wasn't a disappointment with hail larger than 5 inches in diameter, the tornado reports that may have verified were all brief and weak. This year is the lowest since 2005 as far as tornado reports, and is nearly 200 tornadoes below the last 4-year average. While there are plenty of chasers who have still had a good year, most are still very disappointed in the year thus far.

Thus, I am not too disappointed that I have had to miss this years' activities due to the birth of my first little boy. Here's to a hope that we can continue the mediocre year well into June and into this fall over the northern plains.

While I'm on the context of other chasers including TWISTEX, I would like to give my little shout-out to the group that is chasing as a part of the Discovery Channel Storm Chasers crew. TWISTEX is being displayed as a professional and pure scientific research group, as that is what they are! Tim Samaras, Dr. Bruce Lee, Dr. Cathy Finley, and Tony Laubach among others have had some luck this year; they were able to have a successful mission out in Wyoming last week as well as many others. Be sure to follow their updates as I post them on their website: http://www.twistex.org

June 7 Tornado/Wind Survey for Dallas/Polk Counties

The National Weather Service office out of Des Moines issued their public information statement regarding the tornado reports and damaging wind reports that were received as a severe and tornadic thunderstorm moved across Dallas and Polk counties on Sunday evening. The results of the survey indicated that a brief EF-0 tornado occurred south/southeast of Dallas Center. The tornado length was 1.5 miles long, with an average width of 100 yards; the tornado damage path was concentrated within a path of straight line winds which began near Adel and continued northeast. The reports of a tornado near the town of Grimes was investigated and the NWS determined that this was a results of straight line winds that occurred on the southern periphery of the supercell's mesocyclone. A nice image that the Des Moines NWS has posted to their website is below:




To read more details and the complete public information statement please view the survey link: Adel to Grimes Wind Damage Survey

Another Cool Week

Over the past couple of days I couldn't help but hear people whine about how 'cold' it was across northwest Iowa and adjacent areas that were north of the warm front that sparked off several rounds of thunderstorms. It is always ironic to me how people use the word 'cold' to describe the weather; if it was anytime between October and March then people would be very pleased and say that the past couple of days of weather has been 'warm'. Instead, just because we want to see temperatures in the 70s and 80s or even higher we start complaining that it is 'cold' outside. Thus, this posts title will be in regards to the continued cool weather that is expected for what looks to be the remainder of this week.

Today's temperatures range from the upper 50s to mid 60s across a majority of the state, while extreme southeast Iowa was able to stay in the warm sector for a while and saw highs in the 70s and lower 80s. We'll dry off tonight with low temperatures ranging from the mid 40s to mid 50s from north to south. The showers/thunderstorms will return to western Iowa during the evening hours on Tuesday; with highs in the mid 60s to mid 70s from northwest to southeast. The showers/thunderstorms will overspread much of the state overnight on Tuesday, with low temperatures in the 50s throughout the state. Scattered showers are likely to continue over the state on Wednesday, hindering high temperatures to the mid 60s to lower 70s from north to south.

Although there are a few rogue chances of a shower/thunderstorm, we should stay dry through the rest of the work week. High temperatures for Thursday and Friday should range from the lower to mid 70s. Low temperatures in the lower to upper 50s on Thursday night will increase a few degrees to the mid to upper 50s for Friday night.

Feels like May!

After yesterday's high temperatures across the state in the 50s and 60s, along with cloudy and rainy skies, today is much of a relief for those wishing it would actually feel like May. Morning lows were on the chilly side in the mid 40s in the northwest, to the mid 50s across much of the southern tiers of the state. With clear skies overhead today, and only light northerly winds the temperatures will soar into the lower 80s across the western portions of the state and near 70 along the Mississippi River. Temperatures will only get warmer as we continue into the weekend, and the return of southerly flow will allow increased moisture as well. We'll see only partly cloudy skies through the rest of the week, leading to a wonderful start of the weekend.

Low temperatures tonight in the lower to mid 50s across the state, setting us up for highs on Friday from the mid 70s across the northeast quarter to the mid 80s across the southwest. Friday night lows from the lower 50s to upper 50s from north to south are expected as light southerly winds begin to pull in moisture from the south. Highs for the start of the weekend on Saturday will range from the upper 70s to upper 80s from east to west across the state. Lows overnight from the lower 50s to lower 60s from northeast to southwest... Previous forecasts had indicated the potential for thunderstorms on Saturday evening across parts of southern Iowa, however, current model trends continue to push the forecasted low pressure system and associated fronts further south into Missouri. If this model trend holds true then only a slight chance of a thunderstorm or two would see possible across southern Iowa.

Sunday should hold a different story, with a cold front beginning to work down from the northwest and warm/moist temperatures finally in place ahead of the front would lead to strong and potentially severe thunderstorm development during the afternoon/evening hours. Sunday's highs from near 80 to near 90 appears likely from east to west, with dew points approaching 60 across much of the state.

Thunderstorms would be likely along the cold front as it sweeps into northwest Iowa by the evening hours, and continued development would be likely across the state as the front continues to move southeast through the overnight hours. Moderate instability would appear to be present given warm temperatures and modest dew point values, however dew points would still appear to be too low to support strong surface-based development. For this reason it would appear that damaging winds be the main threat with storms along the cold front, with large hail being a secondary threat with any of the stronger storms. More updates on the potential for severe weather for this weekend and next week in later updates!

Severe Weather Drought

Today marked the eighth straight day in which the Storm Prediction Center had not issued a Severe Thunderstorm or Tornado watch over any part of the United States. This is essentially a May record, with eight days of minimal organized severe weather and even one day (May 21) in which not even a single severe weather report was received. For those that are interested in such major projects like VORTEX, this lack of significant severe weather is definitely putting a damper on any hype. At least many are hopeful for a strong start to June, that will hopefully continue through the rest of the month and have mother nature finally give us a good show in the beautiful northern plains states.

Several local chasers/spotters have been using the high plains as chase territory with times like these, minimal moisture is still sufficient at the higher elevations, and low level winds with an easterly component play into good up-slope flow to trigger the convection. A weak/shallow trough is currently over the northern plains, and will create some potential for severe weather across eastern Dakotas and western Minnesota on Memorial Day. However, even with sufficient wind shear over this area, the lack of moisture will likely create high based storms more likely of large hail and some strong wind gusts.

Once this small trough passes through, we'll once again see a ridge in the western half of the CONUS build. Continuing the lack of organized severe weather across the plains states... Forecast models are now beginning to hint at this ridge breaking down towards the last day or two of May and then continuing to support the threat of organized severe weather into the month of June. Once these threats really begin to crank up and enter the forecast, I'll hopefully be able to begin some organized severe weather forecasts for Iowa and adjacent areas.

Chilly Start

After the cold front and associated thunderstorms moved through parts of the state last night, temperatures were finally able to drop well below average across much of the state. Many woke up this morning to temperatures in the mid 30s in northwest Iowa, to the mid 40s across the south and east. The state won't warm up too much even today as cooler northwest flow continues over the state. Expect highs in lower to mid 60s across much of the state today, with low temperatures tonight falling back down into the upper 30s to mid 40s from north to south.

A slight warm up tomorrow, and continued warming trend through the week as thunderstorm chances are introduced beginning Tuesday night. More details on the thunderstorm threat and the chances of severe weather in later updates!

Heavy Rain

The heavy rains that continued through much of the nighttime hours created quite the flooding conditions across the state. Currently it appears that 28 counties are under a flood warning for rivers/streams that are above or forecasted to be above flood stage in the coming hours. Most flooding is minor at this time, with only a few locations forecasted to see moderate flooding for a short time. A look at the observed precipitation for the 24 hours previous to 7 AM this morning across Iowa:



A mix of clouds and light showers expected today, with temperatures only expected in the 50s to lower 60s in a few locations. Look for more sunshine and warming temperatures through mid-week. More details on the weeks forecast in tonight's update!

Severe Weather Recap: April 26

Although thunderstorms are continuing to move across central and eastern Iowa, it appears as if our severe weather threat has become minimal. A few of the thunderstorms entering southern Iowa may have the potential to produce some gusty winds as they continue northeast; otherwise the main threat will be the heavy rains causing flash flooding of low-lying areas.

Both a severe thunderstorm watch and tornado watch were issued for areas of the state today, both of which have now been canceled. Several clusters and line segments of thunderstorm moved across the state, with a majority of reports across central Iowa coming in the form of damaging winds. There was isolated development of a supercell in northeast Iowa ahead of the more linear natured thunderstorms in central Iowa. This supercell did produce several reports of large hail varying from quarter sized to golf ball in diameter. This supercell also produced the first tornado(s) of the year for the state of Iowa, with four reports total coming out of northern Linn county and extreme southern Delaware county. This storm also produced another brief tornado just across the border in Wisconsin. At this time there has not been any significant damage reports with these tornado reports...

Heavy rains are causing flash flooding and flooding of low-lying areas across central and eastern Iowa. This threat will continue through tonight and into tomorrow as the rains continue. Expect the clouds to slowly move out of the area, leaving us will dull skies on Monday; but the sun will return for Tuesday.

Weekend Severe Weather

The bulk of great severe weather chances are likely to be confined to the TX/OK/KS areas both today and tomorrow with a dryline and triple point intersection and ample moisture/instability present. Plenty of chasers are out as we are on a weekend and we are nearing the time frame of May, which is southern/central plains chase heaven. The state of Iowa will try to get its' fair share of severe weather this early in the season too...

A quick recap of yesterday's (April 23) severe weather across the state: Several storms were able to become severe warned yesterday, however, as expected the depth of the moisture was a problem and we ended up with the large hail for the most part, along with a few gusty winds. Large hail ranging from dime to nickel sized, even a few quarters and slightly larger, were reported throughout southwest, central, and northeast Iowa.

Today's (April 24) severe weather threat across the state will be very limited as the cold front has slid through all but extreme southeast portions of the state. This small corner of Iowa may see some thunderstorm development this afternoon with the chance of some large hail and/or damaging winds with these thunderstorms. Light rain and cloudy skies are expected across the remainder of the state, as highs only reach into the upper 40s to mid 50s compared to the 80s and 90s the past two days!

Sunday will have severe weather once again likely across the state as the current cold front begins to move back north as a warm front tonight and through tomorrow. An associated low pressure system should develop and move across western Iowa into southern Minnesota by Sunday evening. There is still big questions in the threat of severe weather given that extensive cloud cover and rain showers may be over the state throughout the day on Sunday. If this does occur, thunderstorms are still likely to develop, however, with a limited severe weather threat of marginally severe hail and gusty winds. If areas of the state ahead of the cold front coming eastward and south of the warm front are able to clear in the afternoon, at least moderate instability should be expected with much better potential for severe weather. An additional quick update tomorrow morning may be available for tomorrow's severe weather threat in Iowa...

Record Highs on April 23

Although nothing will become official until we go past midnight tonight, it would appear very likely that at least three cities saw record high temperatures this afternoon in northwest Iowa. Much of southern Iowa saw cloud cover this afternoon due to an impressive MCV (mesoscale convective vortex) that was initiated across eastern Kansas during the early morning hours and continued across northern Missouri throughout the day. The clouds across much of the south kept temperatures much cooler than expected, with highs only in the mid 70s to lower 80s. This is still well above normal for this time of year, thus nobody should really be complaining!

With clear skies, strong southerly winds, and ample mixing, the temperatures across northwest Iowa soared this afternoon with many stations reaching the mid 80s early in the afternoon. The following are details on the records that are likely to become official at the end of the day:

Sioux City, IA peaked at 3:46 PM this afternoon with a high of 92 degrees. This breaks the old record of 87 degrees that occurred in 1939!

Just previous to Sioux City's high, Sioux Center reached their peak of 89 degrees at 3:38 PM. This ties the previous record that was set in 1990.

Spencer, IA also went above the previous record that was set in 1990. The high today was 86 degrees, which was 2 degrees above the previous record.

Look for temperatures to once again reach into the 80s tomorrow, potentially hovering near the record mark for April 24!