Storm risk updated. Marginal risk of Severe thunderstorms! In March!

It’s very early to be posting about severe thunderstorms but conditions are lining up for the potential of Severe thunderstorms in Central Alberta, the main threat will be damaging winds and perhaps large hail.

There is not enough moisture for flash flooding.

Whether storm turn severe or not the dynamics for today come incredibly early. It’s at least late May before were talking about marginal Severe risk.

Another note is the potential of thunder snow as temperatures

From Focn45 http://kamala.cod.edu/Canada/latest.focn45.CWWG.html

327   
FOCN45 CWWG 311900  
SIGNIFICANT WEATHER DISCUSSION ISSUED BY THE PRAIRIE AND ARCTIC STORM  
PREDICTION CENTRE OF ENVIRONMENT CANADA AT 2:00 PM CDT TUESDAY MARCH  
31 2015.  
  
ALERTS IN EFFECT...SPECIAL WEATHER STATEMENT FOR NORTH-CENTRAL  
ALBERTA.  
  
THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON AND  
EVENING OVER PARTS OF CENTRAL ALBERTA.  
  
SYNOPTIC OVERVIEW...LONGWAVE TROUGH MOVING INLAND OVER WESTERN NORTH  
AMERICA WITH NOTABLE EMBEDDED IMPULSE MOVING THROUGH NORTHERN B.C.  
INTO NORTHERN ALBERTA. UPPER RIDGE SLIDING EASTWARDS ACROSS THE  
PRAIRIES. AT 18Z, 1000MB SURFACE LOW DEVELOPING THROUGH THE ALBERTA  
ELBOW SET TO EJECT EASTWARDS ACROSS CENTRAL PRAIRIES. TWO MAIN  
FRONTAL BOUNDARIES TODAY; FIRST IS A FRONTAL WAVE THROUGH AB/SK, WITH  
NORTH-SOUTH RUNNING COLD FRONT PUSHING INTO WESTERN ALBERTA AND  
MONTANA. THE WARM FRONT OF THIS WAVE RUNS FROM CENTRAL ALBERTA  
SOUTHEASTWARDS THROUGH SOUTH-CENTRAL SASKATCHEWAN INTO THE WESTERN  
DAKOTAS. SECOND BOUNDARY IS AN ARCTIC COLD FRONT RUNNING  
SOUTHEASTWARDS FROM NORTHERN SASKATCHEWAN THROUGH NORTHERN AND  
CENTRAL MANITOBA.  
  
DISCUSSION.  
  
PRAIRIES...A FAIRLY POTENT SPRING STORM IS ON THE WAY FOR MANY ACROSS  
THE CENTRAL PRAIRIES AS A LOW PRESSURE SYSTEM FROM THE ALBERTA ELBOW  
EJECTS EASTWARDS TODAY AND TRACKS ACROSS THE PRAIRIES OVER THE NEXT  
COUPLE DAYS.  
  
ALTHOUGH IT IS ONLY THE END OF MARCH, THE PATTERN OVER ALBERTA TODAY  
IS ONE CONDUCIVE TO THE FORMATION OF THUNDERSTORMS AND EVEN SEVERE  
THUNDERSTORMS (SHOULD MOISTURE BE PLENTIFUL ENOUGH) THAT WE CANNOT  
RULE OUT A STRAY WARNING OR TWO TODAY. THE PATTERN IS RATHER CLASSIC  
SEVERE ALBERTA--80+ KNOTS ALOFT, 50 KNOTS AT H5, SUBTLE TO STRONG  
COOLING MOVING IN, THERMAL RIDGE RIGHT OVER THE PROVINCE IN THE  
MORNING. MODIFYING WSE FOR 17/3 GIVES AN IMPRESSIVE (FOR THIS TIME OF  
YEAR) 750 J/KG. INVERTED-V PROFILES ENSUE SHOULD THIS COME TRUE, AND  
WIND GUSTS IN EXCESS OF 50 KNOTS ARE POSSIBLE. WHILE WE WON'T LIKELY  
ISSUE ANY WATCHES FOR THE REGION, IT WOULD NOT BE SURPRISING TO NEED  
TO ISSUE THE FIRST SEVERE THUNDERSTORM WARNING OF THE SEASON. AT THE  
VERY LEAST, WE HAVE INSERTED GUSTS TO 80 KM/H INTO THE PUBLIC  
FORECASTS WHERE APPROPRIATE.  
  
AFTER THE PASSAGE OF THE COLD FRONT, A FAIRLY PERSISTENT HEAVY SNOW  
WILL FALL IN WHAT SHOULD BE A CONVECTIVE BAND. THIS WILL LEAD TO THE  
POTENTIAL FOR WARNING-LEVEL SNOW, AND THE REGIONS HIT BY IT ARE NOT  
AT ALL CLEAR--IT COULD BE ANYWHERE FROM THE PEACE COUNTRY TO FORT  
MCMURRAY. SHORT-FUSE SNOWFALL WARNINGS WILL LIKELY OCCUR HERE.  
HOWEVER, FARTHER EAST, IN NORTHERN SASKATCHEWAN, THE SNOWFALL SEEMS  
TO BE MORE AGREED-UPON, AND AS A RESULT WE WILL LIKELY ISSUE SOME  
SNOWFALL WARNINGS THIS AFTERNOON.  
  
FINALLY, AFTER THE PASSAGE OF THE AFOREMENTIONED COLD FRONT, SYNOPTIC  
WINDS WILL BE STRONG AND GUSTY. PARTS OF EAST-CENTRAL ALBERTA WILL BE  
IN A RATHER TIGHT GRADIENT AND THERE WILL BE 50 KNOTS OR SO TO MIX  
DOWN. WARNINGS AREN'T BEING CONSIDERED--YET--BUT WARNING WINDS CANNOT  
BE RULED OUT TOMORROW.  
  
PRECIPITATION WITH THIS SYSTEM SHOULD MAINLY BEGIN AS RAIN TODAY AND  
THEN GRADUALLY CHANGE OVER TO SNOW TONIGHT. THIS SYSTEM WILL BE  
BOLSTERED BY AN INJECTION OF MOISTURE THIS EVENING THAT MAY RESULT IN  
SOME WEAK CONVECTIVE SHOWERS OVER SOUTHERN SASKATCHEWAN. THE SYSTEM  
WILL BRING THE THREAT OF HEAVY SNOW TO SEVERAL NORTHERN COMMUNITIES  
FROM PELICAN NARROWS IN SASKATCHEWAN ESE TO ISLAND LAKE, MANITOBA.  
ENSEMBLE SNOWFALL SOLUTIONS HAVE BEEN PUSHING 12 HR. SNOWFALL TOTALS  
TO THE 10-12 CM RANGE, HOWEVER ACTUAL TOTALS WILL DEPEND  
SIGNIFICANTLY ON THE EXACT POSITIONING OF THE RAIN-SNOW LINE AND THE  
TIMING OF THE SWITCH-OVER TO SNOW. IN ADDITION TO THE SNOWFALL,  
STRONG NORTHERLY WINDS TO 40-50 KM/H WILL LIKELY PRODUCE PERIODS OF  
POOR VISIBILITIES IN BLOWING SNOW DURING THE SNWFALL EVENT.  
NO WARNINGS HAVE BEEN ISSUED AT THIS TIME FOR THIS SYSTEM, HOWEVER WE  
WILL BE MONITORING IT CLOSELY AND SOME WINTERY WARNINGS ARE POSSIBLE,  
PARTICULARLY THROUGH THE AFOREMENTIONED REGIONS.  
  
THE SECONDARY THREAT FROM THIS SYSTEM WILL BE THE SURGE OF COOLER AIR  
ON THE BACK-SIDE OF THE SYSTEM. AFTER BASKING IN SPRINGTIME WARMTH,  
MUCH OF THE PRAIRIES WILL SEE BELOW-NORMAL TEMPERATURES RETURN BY  
WEEK'S END. TWO MAIN AREAS OF SIGNIFICANT WEATHER WILL BE WORTH  
KEEPING AN EYE ON AS THE COLD FRONT PASSES ON WEDNESDAY. THE FIRST IS  
OVER SOUTHWESTERN SASKATCHEWAN INTO SOUTHEASTERN ALBERTA WHERE THE  
COLD FRONTAL PASSAGE WILL BE MARKED BY INSTABILITY AND NOTABLE WINDS.  
AT THIS POINT, WINDS OF 40-50 KM/H SEEM QUITE LIKELY ALONGSIDE  
CONVECTIVE SHOWERS OR FLURRIES. IT'S STILL EARLY, HOWEVER THERE IS A  
SLIGHT POTENTIAL THAT WE MAY EVEN SEE SOME SNOW SQUALL ACTIVITY  
BEHIND THE COLD FRONTAL PASSAGE LATE WEDNESDAY INTO WEDNESDAY  
EVENING. THE SECOND, LESSER, AREA OF CONCERN WILL BE THROUGH THE  
MANITOBA INTERLAKE AND RED RIVER VALLEY WHERE SOME FLURRIES WILL MOVE  
THROUGH ALONGSIDE STRONG NORTHERLY WINDS.  
Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s