Signs that Potentially Record Breaking Warmth May Continue

If there's one thing to be learned this winter, it is this: Many models look like they're just taking stabs in the dark. And this was true, especially for respected models like the ECMWF and GFS, to those lesser-used JMA, CMC, NOGAPS models.
But there were a select couple of correct models. The model shown above is the NAEFS Ensembles, or the North American Ensemble Forecast System. This model was the lighthouse in this sea of model uncertainty. It nailed all predictions for a warm winter. That said, I am investing confidence in it yet again to formulate this forecast.

Using the NAEFS, the period between the next 8 days and next 14 days (Days 8-14) tells of widespread areas with temperatures that are at a 90%+ probability for being above the normal temperature. This is most common in the Plains and Canada, with a little cooler forecast to the east.
Now, I am a little hesitant to believe this, because the atmospheric feature that has been causing this record-breaking heat is now moving away. It is a mega-ridge of high pressure, and it is slowly moving to the east, offshore the US. This means more storm systems will be able to pass through that area and therefore create a more progressive temperature pattern of cold fronts and warm fronts. Or so it would be thought.
While the NAEFS is not a forecaster for hourly SLP (sea level pressure (low areas are low pressure systems, high areas of SLP are high pressure areas)), using long range precipitation accumulations, I can determine that the storm track looks to be suppressed south according to the NAEFS. This would indeed allow a buildup of air to occur in the North Tier of the US, and this air would likely be warm, using the temperature forecast.

-Andrew

Temperatures to Moderate in Next Several Days

WB013_MAXTEMP_WEEKDEP_E_2.png

Temperatures will be moderating in the next several days, stopping the record-breaking heat in its tracks. The image above shows maximum temperature departures (maximum or minimum temperatures) for March 27 to April 2. As you can see, temperatures may even be below normal in the Ohio Valley, with the warmth stationed in the North Plains and Northwest parts of the US.
This cool down comes as the mega-ridge of high pressure will be shoved offshore, bringing the warm weather with it and putting jackets and jeans back in style.

-Andrew

Rough Night Ahead for Texas, Oklahoma

Here's the latest forecast off Norman, Oklahoma's National Weather Service Office WRF Model. It is showing something I certainly would not want to be in, with rampant bowing segments and intense storm cells. Judging by this image (which is valid at 5:15 PM CDT), this is probably a bit overdone, but nonetheless sending a warning message which should validate, even if the image should not.
The storms currently in progress have a good 1000-2000 j/kg of instability to work with, which should sustain any storms that do develop. But then here's the thing that could push the storms to the next level- frontogenesis.

Current Surface Frontogenesis

The whole concept of watching for elevated levels of frontogenesis is that it helps severe storms. Frontogenesis means the making of a frontal boundary, and we weather folk know that storms favor frontal boundaries to form and become the strongest along a frontal boundary. You know there is a frontal boundary present when there are elevated levels of frontogenesis, and in this case, the levels are sky-high, only adding to the case to enhance severe storms.

My Thoughts include that these storms will move into southeast Texas, where more instability will be available. As the sun sets, daytime heating will take a big punch out of storms, but if there remains strong frontogenesis and fair lifting and instability mechanisms, the storms could certainly continue along through the night.

-Andrew

As Promised...

As promised, something big will be happening with 100 models and ensembles on our Models page coinciding with 500,000 views on the blog. And now I'm happy to say that ALL long range forecasts on the poll on the right will be published! Dates will be announced soon.
Also, updates concerning the severe storms in the Plains will be coming this afternoon.

Moderate Risk for Severe Thunderstorms Today

Hail Outlook

Tornado Outlook

Damaging Wind outlook

The Storm Prediction Center has issued a moderate risk for severe weather on account of the risk for damaging winds today, and it is a very valid risk. Take a look at this short term forecast from the Marquette, Michigan's WRF model.

This WRF model is predicting scattered storm cells to come together to form a strong squall line. This WRF is one of many WRF's run at different NWS forecasting offices. Just taking a glance at some other WRF model runs tells me that it may be even worse than this, with the Norman, Oklahoma WRF forecasting extreme storm cells in the TX/OK region.

Here's the Storm Prediction Center's Public Severe Weather Outlook

PUBLIC SEVERE WEATHER OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0321 AM CDT MON MAR 19 2012
...WIDESPREAD SEVERE THUNDERSTORMS EXPECTED OVER PARTS OF THE
SOUTHERN PLAINS TODAY AND TONIGHT...
THE NWS STORM PREDICTION CENTER IN NORMAN OK IS FORECASTING THE
DEVELOPMENT OF WIDESPREAD DAMAGING WINDS...VERY LARGE HAIL AND
TORNADOES OVER PARTS OF THE SOUTHERN PLAINS TODAY AND TONIGHT.
THE AREAS MOST LIKELY TO EXPERIENCE THIS ACTIVITY INCLUDE
FAR SOUTHWEST ARKANSAS
SOUTHEAST OKLAHOMA
CENTRAL INTO NORTHEAST TEXAS
ELSEWHERE...SEVERE STORMS ARE ALSO POSSIBLE FROM THE MID-MISSOURI
VALLEY TO THE TEXAS GULF COAST.
A POWERFUL UPPER-LEVEL STORM SYSTEM OVER THE INTER-MOUNTAIN WEST
WILL SHIFT EASTWARD INTO THE GREAT PLAINS TODAY IN CONJUNCTION WITH
A SURFACE COLD FRONT. A LINE OF SEVERE THUNDERSTORMS HAS DEVELOPED
EARLY THIS MORNING AHEAD OF THE COLD FRONT OVER WESTERN PORTIONS OF
TEXAS AND OKLAHOMA. THESE STORMS ARE EXPECTED TO CONTINUE THROUGH
THE MORNING ACROSS PARTS OF OKLAHOMA AND NORTHERN/WESTERN TEXAS WITH
ASSOCIATED THREATS FOR DAMAGING WINDS AND LARGE HAIL.
TO THE SOUTH OF THIS INITIAL THUNDERSTORM ACTIVITY...THE INTERACTION
OF MOIST AND MODERATELY UNSTABLE AIR MASS WITH STRONG...LOW AND
UPPER-LEVEL JET STREAM WINDS WILL CREATE AN ENVIRONMENT FAVORABLE
FOR INTENSE THUNDERSTORMS...INCLUDING SUPERCELLS...ACROSS PARTS OF
CENTRAL AND NORTHERN TEXAS INTO SOUTHEAST OKLAHOMA LATER TODAY.
LATEST WEATHER MODEL DATA INDICATE THAT MULTIPLE WAVES OF
THUNDERSTORMS WILL BE POSSIBLE FROM THIS AFTERNOON THROUGH TONIGHT
ACROSS THIS GEOGRAPHICAL AREA. VERY LARGE HAIL TO BASEBALL SIZE OR
LARGER AND WIDESPREAD DAMAGING WINDS APPEAR LIKELY...ALONG WITH THE
POTENTIAL FOR A FEW TORNADOES.
STATE AND LOCAL EMERGENCY MANAGERS ARE MONITORING THIS DEVELOPING
SITUATION. THOSE IN THE THREATENED AREA ARE URGED TO REVIEW SEVERE
WEATHER SAFETY RULES AND TO LISTEN TO RADIO...TELEVISION...AND NOAA
WEATHER RADIO FOR POSSIBLE WATCHES...WARNINGS...AND STATEMENTS LATER
TODAY.

-Andrew