Friday, October 3, 2014

Early October Snow, say it aint snow

Light to moderate snow has been reported in Northwestern Wisconsin during the overnight hours! The snow is expected to drop south overnight and eventually pivot around a strong area of low pressure to the east during the early morning hours on Saturday, any accumulation will be light. May we remind you its October...5 days ago many of these locations will in the 80s!

The first map below is of the HRRR (experimental run) of total snowfall over the next 14 hours! It has a pretty good handle on how this system is evolving.

Finally, the last map is of 850mb temperatures for 6z Saturday.  It is showing the expansive cold encompassing much of the Midwest.  Record low maximums are in jeopardy Saturday! The well below normal temperatures appear to hold strong right on through the next week and beyond.

Wednesday, September 10, 2014

Cold Front Passing Through

Those narrow strips of reflectivity on the NEXRAD radar are actually the leading edge of a strong cold front, which will continue to push south and east today. Much cooler weather is on the way for tomorrow and even more so on Friday, where some places will be stuck in the 40s! 

Sunday, September 7, 2014

Severe Weather ---> Excessive Cold ----> Snow Flurries?

After a tranquil Sunday and relatively quiet Monday, the world of weather in the Midwest will become much more active by Tuesday.  A developing area of low pressure will push through the Midwest early Tuesday and drift NE through Wednesday.  East of the system a more humid and unstable airmass will encompass the shaded area.  Severe T-storms should develop in and around the shaded areas. Damaging winds and large hail appear to be the primary threats.

Flooding will also pose troublesome with much of the Midwest saturated from recent heavy rains.

As the system pulls away Thursday, winds will shift out of the northwest and usher in the coldest air of the season. It will certainly feel like fall with a cool dry airmass in place. High temperatures on Friday will be running 15-20 degrees below normal across most of the central part of the country. Areas north of a line from Green Bay to Minneapolis to Rapid City could deal with some frost by the end of the week, or maybe even a hard freeze. Much of the Midwest will see highs in the 50s and 60s respectively.

On the left is the latest 6-10 day temperature outlook from the Climate Prediction Center.  It shows the likelihood of temperatures below the normal mean temperature during a specified time period.  For those that follow these maps, dark shades of blue are extremely rare. In recent days the dark blues are appearing as frequently as the did earlier in the Spring during the winter that never seemed to end. Another prolonged period of even colder weather has popped up in the computer models. The European model has another strong cold front passing through early next week with accumulating snow in northern Minnesota, we will see how this one plays out in coming days.

The WPC is forecasting high temperatures in the 50s for the NW half of the Midwest. Going conservative 5 days out, these highs could even be lower than depicted on the right. High pressure builds in for Thursday night and Friday night, which could set the stage for near record low temperatures during this time period.

With it being the first major shot of cold air, we will closely watch how the models handle it to get a gauge on the rest of the summer and into Autumn for future forecasts.

Just for kicks, below is the EURO model for next Monday as the cold front pushes through...

Friday, September 5, 2014

Exceptional Chill on the Way Late Next Week

The coldest air of the season is building up in northern Canada and will dive south into the continental United States by late next week.  The jet stream will pinch out a trough in the midsection of the country and allow for the ushering of much cooler air.  Temperatures will run 10-20 degrees cooler than average. The map on the left shows the likelihood of below normal temperatures, notice the substantial area of dark blues encompassing the northern Great Plains. This weather will likely bring the first 30s in northern Minnesota and a couple snow flakes cannot be ruled out, as 850mb temperatures dip below 0C. The map on the bottom shows the expanse of the cold, with the 0C line dipping excessively south.


Just to give a snapshot of what some of the models are is the latest EURO model run for minimum temperatures next Friday night and Saturday morning. Showing widespread lows in the 20s! While this scenario is extremely unlikely, record low temperatures may be within reach. The GFS is outputting similar, yet more conservative numbers. One rule of thumb this summer is that the EURO does tend to go cold a week out, it will be interesting to watch the cold unfold in the models throughout the next several days.


After record high temperatures across the Midwest the past few days, this weekend will begin to serve as relief for most areas.  By Sunday we return to near average highs and stay around average until late next week when the reinforcing shot of cold air comes in! Happy Fall.

Friday, July 11, 2014

NO POLAR VORTEX, A Quick Explanation and Misconseptions

Thoughts on Recent "Polar Vortex" Forecast:

Well....Polar Vortex coming next week, good joke. To clear up one of the largest misconceptions in the public weather belief, this winter we never had the polar vortex over us....just various pieces of cold air from this synoptic scale circulation that someone decided to call the whole "polar vortex" in the media somewhere! Furthermore, the polar vortex is formed by pools of cold air of which are caused by long dark nights and significant snow cover. It is then trapped near the north pole by a strong west to east jet stream....but since its summer and light 20-24 hours a day this pool of very cold air never fully develops and the snow pact sees and large dent in its depth.  Yes, early next week will bring a "similar" upper level pattern to January, but NO Polar vortex.  Anyways....if you are stuck in clouds Monday and Tuesday highs will be nearly 20 degrees below normal in most places!
Please spread the word if you hear friends chatting about the upcoming polar vortex or share on Facebook! Good night all.

Wednesday, July 9, 2014


Here is the latest 6-10 day outlook from the Climate Prediction Center, this is looking like the same weather pattern in late winter and early spring!

Some computer models have low temperatures in the upper 30s over the weekend in the far northern Great Plain, nonetheless in the lower 48!

For the Midwest....any days of complete cloudiness during the afternoon will likely keep highs 15-20 degrees below normal!

Saturday, July 5, 2014

Strong and Severe Thunderstorm Across the Midwest Sunday

An area of low pressure will pass through the Northern Great Lakes on Sunday bringing the threat for severe weather across Iowa, Wisconsin and northern Illinois.
Winds will shift into a more southerly direction on Sunday, this flow ushers in a much more humid and unstable atmosphere during the afternoon building a high CAPE values. With a cold front trigger and upper level shear the atmosphere will be primed in the yellow area and especially in the red shaded area on the map to the left.

On the right is the NAM Hi-Res Simulated Radar off the 00z model run. It shows a line of strong to severe thunderstorms developing in the Upper Mississippi River Valley during the late afternoon and passing through Wisconsin and Illinois in the evening hours. This is one solution, but this model has been fairly reliable in recent weeks.

The 18z GFS run develops the heaviest thunderstorms around 8-10pm and puts the location of the cold front from Lake Superior to Central Iowa around 10pm Sunday.  With this in mind, any storms to do form into an MCS or line should hold together into the early overnight hours as severe dynamics should still be in place, according to the GFS.

The latest model run can be found in the "Computer models" tab at the top of this screen.

Monday, June 16, 2014

Widespread Damaging Wind Event Likely Monday into Tuesday

Severe thunderstorms capable of potentially widespread damaging wind...very large hail and tornadoes...a couple of which could be significant...will occur today into tonight from parts of southeast South Dakota and central and eastern Nebraska eastward across much of Iowa...southern Minnesota...into Wisconsin.

A trough over the western United States will intensify during the day one period in response to the equatorward progression of mid and upper-level jet streaks from the far northern pacific into the trough base over the great basin. Downstream from these developments...morning water vapor imagery indicates a low-amplitude short-wave trough progressing into the northern and central plains with this feature continuing eastward development into the upper great lakes by late tonight/early Tuesday.

Tuesday, June 3, 2014

Major and Destructive Severe Weather Outbreak Underway

Property and life threatening severe weather event is evolving at this hour. The atmosphere is primed for excess severe weather and will continue to become worse throughout the evening hours.  A possible derecho will form as we head into the evening and overnight hours. I line of severe thunderstorms will form and push east, mostly concentrated in the "extreme" shaded area on the left. Large hail, damaging winds and extremely heavy rain will be the main threat this evening. There have been reports of rain rate of 8" per hail and hail over 4" already. This is a dangerous situation and any severe thunderstorm warnings need to be taken with a serious attitude. Be sure to watch the local forecasts and local alerts if you reside in these areas!

Below is the forecasted supercell composite for late this evening ~10pm CDT.  These values are extreme!! Anything over 10 is a dangerous situation, we are seeing values of 44! Crazy, stay safe!

Monday, June 2, 2014

Severe Weather Likely Tuesday Afternoon and Evening

Numerous strong to severe thunderstorms are forecasted to develop in the Great Plains on Tuesday.  Damaging winds and large hail are certainly on the way for tomorrow, but the threat for a few strong tornadoes also persists through the afternoon and evening on Tuesday. The highlighted area in red/dark orange appears to be the hot spot tomorrow. Outdoor plans and location of parked cars should be considered for those who resides in these areas. 16 millions people are in the highest risk area tomorrow.

More information will be posted later tonight.

Lake Superior Continues to Hold Ice

For the first time ever, (since records were kept) Lake Superior has a concentration of ice over 2% as of the first of June.  All of the ice or ice burgs have drifting to the southern shore. Even with the recent warm weather over the past several weeks, the ice had held its own, with high concentration of ice in some locations. For example, the map on the left side shows concentration near Marquette, Michigan of over 50%.  As expected, water temperatures are in the 30s and 40s across the lake. May a June Polar Plunge be in store?...

On the right is a computer model forecast of ice concentration over Lake Superior.  It shows the continuation of ice cover or parts of the southern shore into the weekend, which will likely break more ice cover records after one of the coldest winter off all time across parts of the Midwest this year. For a perspective the map below is the average date of the last ice cover over the Great Lakes, notice how March into early April is usually the last date of ice cover, not June!

Tuesday, May 20, 2014

Warm and Summer-like Temperatures Through the Next 10 Days

Well above normal temperatures are on the way for all of the Midwest this week and into next week as the jet stream lifts north into Canada for much of the next two weeks. A small cold pocket of air will rotate on through parts of the western Great Lakes on Thursday, but will be short lived as winds kick over to a more southerly direction yet again on Friday.

Memorial Day Weekend will be nice across all of the Midwest, temperature-wise with highs in the 80s for much of the area. A few strong to severe thunderstorms are possible across the entire area on Sunday and Monday as a disturbance passes through, stay tuned for severe weather updates for the Memorial weekend.

On the right is a snapshot of 850mb temperatures Memorial Day morning. It is a good example of the general pattern that will shape the Midwest over the next couple weeks...A strong area of high pressure to the east allowing for a southerly wind around the clockwise rotation of a high pressure. This wind direction will usher in warm Gulf air as a continuous fetch of wind will set up from the Gulf all the way into southern Canada. A summer pattern indeed.

Severe Weather Threat Rapidly Increasing Tonight

A brand new severe thunderstorm watch has just been posted for much of Iowa and Northern Illinois. Strong to severe clusters of thunderstorms are developing behind a strong warm front and an area of strong convergence. With a hot and humid air mass in place, the atmosphere is primed for further development this evening and into the overnight. The severe thunderstorm watch is in effect until 11:00pm CDT.

Below are the current CAPE values, basically a general telling of the amount of energy a T-storm has to work with at the given time. It can be increased by surface warming and environmental factors.

Below is current (5:00CDT) Bulk-Richardson number across the Midwest, a basic composite value for severe weather.

Below is the Craven-Brooks severe weather composite value.
It is the product of 100mb MLCAPE and 0-6km magnitude of the vector difference (m/s; often referred to as "deep layer shear") accounts for the compensation between instability and shear magnitude. Using a database of about 60,000 soundings, the majority of significant severe events (2+ inch hail, 65+ knot winds, F2+ tornadoes) occur when the product exceeds 20,000 m3/s3.

Monday, May 12, 2014

Low Pressure System to Pose Severe Weather Threat

The severe threat will continue late afternoon through the overnight hours and a slow moving are of low pressure passes through. Strong Gulf moisture and southerly winds are creating ideal conditions of thunderstorm development. Once the cold front passes, the threat will rapidly diminish from west to east tonight and into Tuesday. Behind the cold front temperatures will run 10-20 degrees below average, this weather will last into the weekend before we see moderating temperatures yet again.

Saturday, May 3, 2014

Summer Weather on the Way for Many!

After a prolonged area of low pressure separate from the jet stream controlled the cool and active weather for the eastern half of the country, called a cut off low, a change is on the way. Temperatures will run above average by the middle of the next week, if not earlier. The jet stream will bump north allowing for warm southern air to filter in all week. An area of low pressure will develop and sift out of the Rockies and push towards the Midwest. Exactly where the track of the system falls will be a major factor for the weather in the Midwest next week.
The map on the above is showing the current model consensus of where this system will be near on Thursday.
The warm sector (to the east of the
cold front and to the south of the
warm front) will see highs in the 70s and 80s area wide. This will likely be the first 80 for many in the Midwest. With dew points on the rise and ample surface heating, the atmosphere will become prime for severe weather, with CAPE values approaching 3000 J/KG from Wisconsin on south. A severe weather outbreak is certainly possible on Thursday in the warm sector and ahead of the cold front. We will have to see just where and when this system sets up. The 00z GFS (below) is firing up some thunderstorms for Thursday evening along the cold front. While the front will not bring much in the way of colder air, it will create necessary lift and convergence to develop strong to severe thunderstorms with heavy rains. Back to the temperatures, the chart above is forecasted high temperatures for late next week off the 00z GFS model run. Another temperature map is attached below coming off the European weather model, showing a major range of temperature across the Midwest. The barrier between warm and cool with depend solely on the track of the system mentioned above, either way warmer weather and a kick start to severe weather is on the way for the first full week of May.

Tuesday, April 29, 2014

Severe Weather Threat Shifts East, More Cool Weather Ahead

After a day that brought over 50 tornadoes, another busy day in the severe weather world is beginning to ramp up yet again. Much of the activity will strike Alabama, Mississippi and North Carolina, where vertical wind shear will be greatest. However, there is a slight risk of severe weather from Michigan to Ohio on south. The primary threat with these storms will be damaging winds and large hail. Points further west will continue to see scattered showers.

Here is the 6-10 day temperatures departure across continental United States.
This has been a familiar map this winter, showing below normal temperatures for much of the Midwest while the warm air is suppressed to the south. The jet stream will surge across the country creating a strong barrier from warm to cold.

Sunday, April 27, 2014

MAJOR SEVERE WEATHER OUTBREAK, Midwest avoids the worst of the action

A large line of strong to severe thunderstorms is pushing through the Midwest. The main threats will be damaging winds as the line continues to race to the Northeast. A few embedded tornadoes are possible ahead of the line, called gustnadoes. The horizontal shear in the winds can cause rapid spin-ups and cause a quick damaging tornado, stay safe as the line passes through your neighborhood. The line will weaken as it pushes into more stable air.
Meanwhile, a major tornado outbreak is getting ready to break out further south. A HIGH risk of tornadoes is now in effect for the areas in pink below:

Monday, April 21, 2014

When Will Winter Let up and Toss in the Cards?

Signs are pointing to well below normal temperatures during the 5-11 day period, as the jet stream dips well south allowing for the pouring of cold Canadian air. Some computer models are developing a storm system 8-10 days out with a cold (possibly snow) sector on the back side. We will wait and see how this plays out in the coming days.

Wednesday, April 16, 2014

Another Major Winter Storm, Warmer Weather Looming

Yet another winter storm will strike the Upper Midwest Wednesday and Wednesday night. The accumulating snow will add up in the same areas that were hit with heavy snow numerous times in the past month. Record seasonal snow totals will be set and tacked onto. Winter storm warning and advisories are in effect. Light to moderate snow had already developed in the Dakotas this morning and will continue to expand and push east throughout the afternoon. The snow will becoming heavy and have a major effect on visibilities.

Here are the latest watches/warnings/ advisories from the National Weather Service. A map you might expect for January, dozens of countys are under winter storm warnings where over 6" of snow can be expected. The snow will continue into the night for most and taper off by Thursday morning. Points further south will be affects by a light wintry mix and a cool rain, as the system rides the upper level jet stream to the east northeast. Skies will clear in western areas, and with a fresh snow cover, low temperatures will plummet by morning.

In other news, a warm up is in the cards by next week. The jet stream will bump north and with a strong high pressure in the eastern half of the country, the overall flow will be conducive for warm air advection. Southerly winds begin Sunday and Monday which will set the stage for a warm and abundant sunshine week, for the most part. By this time next week May is right around the corner, so wishful and climatology thinking will say that the "warm" weather should be here to stay, but with this winter in mind, anything is possible. Enjoy the Roller Coaster ride of weather the next several days.

On the right is high temperatures for Sunday off 00z European model run. Other models delay the warm up to Monday. While this model may have slightly over done the warmth on northern fringes, well above temperatures are on the way early next week.

Saturday, April 12, 2014

Severe Weather Expected Later this Afternoon

Severe weather will ramp up in parts of the midwest later this afternoon, as a area of low pressure passes to the west of the threat area. The main severe weather threat will be large hail and maybe damaging winds. The map on the left shows the probability of hail within 50 miles of any point. Severe weather will not effect everyone in these areas, but heavy rain is a near certainty. A widespread 1-3" from Nebraska to Michigan will create flooding problems in low laying areas.
Below is the possible rain totals: