Wed. May.2, 2012 + Thurs - svr tstorms?

[DarkSky]

Rob Kuhn is an EC meteorologist and gives this outlook:

Kuhny on Nocturnal Storm Patrol

1. TODAY..THREE AREAS OF INTEREST TO DEAL WITH..ONE BEING WINTER
WEATHER OVER THE FAR NORTH.THE SECOND BEING POSSIBLE SEVERE
THUNDERSTORMS SWRN ONTARIO BEGINNING THIS AFTERNOON..AND THE THIRD
BEING PATCHY DENSE FOG MAINLY OVER THE GTA AND ERN ONTARIO REGIONS
THIS MORNING.

2. FIRST AREA..OVER THE FAR NORTH, WE KEPT A FREEZING RAIN WARNING
GOING FOR PEAWANUCK ALTHOUGH THE TOWN SITE MAY BE CLOSE TO THE
NORTHERN EDGE OF THE FREEZING RAIN-ICE PELLET-SNOW TRANSITION AS THE
LOW FOLLOWS A SLIGHTLY FURTHER SOUTH TRACK FROM KENORA TO NORTHERN
JAMES BAY. BIG TROUT LAKE LOOKS TO BE A SNOW-ICE PELLET MIX WHICH
SHOULD HOLD ACTUAL SNOWFALL ACCUMULATIONS TO NEAR 5 CM TODAY.
ELSEWHERE NORTH OF THE FRONT SNOWFALL AMOUNTS OF A COUPLE CM SEEM
LIKELY, WITH FORT SEVERN NOW EXPECTED TO MISS THE ACTION WITH CHANCE
POPS OF FLURRIES. THE ARCTIC COLD FRONT IN THE WAKE OF THE LOW
SHOULD EXTEND SOUTHWEST FROM THE LOW JUST NW OF ATTAWAPISKAT TO
JUST SOUTH OF RED LAKE BY THIS EVENING. SCATTERED SHOWERS AND
PERHAPS AN ISOLATED BRIEF NON-SEVERE THUNDERSTORM ARE POSSIBLE OVER
THE REST OF NRN ONTARIO IN ADVANCE OF THIS FRONT.

3. SECOND AREA..MEANWHILE OVER SWRN ONT AS A POLAR WARM FRONT GETS
CLOSER, THE AIRMASS IS EXPECTED TO DESTABILIZE THIS AFTERNOON AND AS
THE COOL AIR BECOMES VERY SHALLOW, IT WILL BE QUITE POSSIBLE FOR
THUNDERSTORMS TO BECOME BASED IN THE BOUNDARY LAYER PARTICULARLY SW
OF LONDON TO WINDSOR. WITH FORECAST MLCAPES OF NEAR 1500 J/KG AS PER
SREF (GEM SOUNDINGS HINT AT EVEN HIGHER MLCAPES BUT THEY MAY BE A
BIT TOO GENEROUS), AND EFFECTIVE SHEARS OF 30 KNOTS AND FORECAST
STORM RELATIVE HELICITIES OF 150-200 M2/S2 NEAR THE WARM FRONT (AND
POSSIBLY NEAR LAKE BREEZE BOUNDARIES SHOULD THEY SET UP), IT'S QUITE
POSSIBLE WE MAY BE DEALING WITH ROTATING SUPERCELLS AND MESOCYCLONES
ON OCCASION ON RADAR. HAVE INDICATED SLIGHT RISK SEVERE WITH MAIN
THREATS BEING TORRENTIAL DOWNPOURS AND DAMAGING WINDS AND INTENSE
LIGHTNING THIS AFTERNOON, BUT LARGE HAIL AND ISOLATED TORNADOES
AREN'T COMPLETELY OUT OF THE QUESTION ESPECIALLY IF THE WARM FRONT
ITSELF CAN MAKE IT INTO SWRN ONTARIO BY MID TO LATE AFTERNOON. A
FAIR AMOUNT OF CLOUD COVER MAY LIMIT INSOLATION AND DESTABILIZATION
SO STAY TUNED.

3. THIRD AREA..PATCHY FOG OVER ERN ONTARIO TO ABOUT AS FAR WEST AS
HAMILTON HAS BECOME DENSE IN A NUMBER OF LOCALES IN THIS MOIST
AIRMASS. HENCE HAVE ISSUED A SPECIAL WEATHER STATEMENT TO GIVE
COMMUTERS A HEADS UP FOR LOW TO NIL VISIBILITY IN PATCHY DENSE FOG.
THE FOG WILL LIFT LATER THIS MORNING.

4. TONIGHT..SLIGHT RISK SEVERE THUNDERSTORMS THIS EVENING SWRN
ONTARIO AS WARM FRONT LIFTS NORTHEAST. INSTABILITY SHOULD DIMINISH
SOMEWHAT WITH SUNSET, BUT THERE APPEARS TO BE AT LEAST SEVERAL
HUNDRED J/KG OF ELEVATED CAPE AVAILABLE NEAR THE WARM FRONT
SUGGESTING POSSIBILITY OF WARM FRONTAL THUNDERSTORMS WELL INTO THE
NIGHT OVER MUCH OF SRN ONTARIO. FOG PATCHES WILL ALSO LIKELY REFORM
ACROSS SRN/ERN ONTARIO IN THE MOIST AIRMASS. ACROSS NRN ONTARIO BAND
OF FREEZING RAIN/ICE PELLETS NEAR PEAWANUCK WILL SHIFT SEWD AND PULL
OUT WITH A COUPLE CM OF SNOW IN ITS WAKE BEFORE ENDING BY MORNING AS
THE LOW PRESSURE AREA DEPARTS INTO NWRN QUEBEC. COLD FRONT SHOULD
GET TO A SRN JAMES BAY - NRN LAKE SUPERIOR LINE BY MORNING.

5. THURSDAY..WARM FRONT CONTINUES TO LIFT NORTHEAST ACROSS SRN
ONTARIO AND HENCE IT PLUS LAKE BREEZE BOUNDARIES PLUS WEAK VORT
MAXES ZOOMING ACROSS FROM THE US MIDWEST COULD ALL SERVE AS TRIGGERS
FOR CONVECTION. WITH MLCAPES OF 1000-1500 J/KG FORECAST IN THE WARM
AIR AND DECENT PWAT VALUES OF 30-40 MM, AMD EFFECTIVE BULK SHEARS
OF NEAR 30 KTS NEAR THE WARM FRONT HAVE GONE WITH SLIGHT RISK SEVERE
TSTMS SRN ONTARIO. PLACEMENT OF WARM FRONT WILL BE CRUCIAL AND IT'S
ACTUAL POSITION MAY BE AFFECTED BY OUTFLOW FROM TSTMS ESPECIALLY IF
THEY BECOME ORGANIZED. HENCE CONFIDENCE IN MAX TEMPERATURES
ESPECIALLY THOSE REGIONS NEAR THE FRONT SUCH AS TORONTO TO BARRIE
IS LOW. A FEW NON-SVR TSTMS POSSIBLE IN ERN AND NERN
ONTARIO AHEAD OF THE WARM FRONT WHERE INSTABILITY IS LESS AND
NON-SURFACE BASED. CONSIDERABLY COOLER ACROSS NWRN ONTARIO IN THE
WAKE OF THE ARCTIC FRONT.

6. IN THE LONGER RANGE..FORECAST PROBLEM WILL BE TIMING A COLD
FRONTAL PASSAGE ACROSS SRN/ERN ONTARIO FRIDAY. MOST OF THIS REGION
SHOULD BE IN THE WARM AND HUMID AIR WITH TEMPERATURES IN THE LOW
TO MID TWENTIES FOR AT LEAST PART OF THE DAY. COOLER AIR ACROSS ALL
OF NRN ONTARIO AS RIDGING BUILDS IN FROM AN ARCTIC HIGH MOVING SE
FROM NUNAVUT. A GRADUAL COOLING TREND AND FAIRLY DRY WEATHER IS
EXPECTED ACROSS SRN/ERN ONTARIO INTO THE WEEKEND AS THE RIDGE
SLOWLY BUILDS SOUTHEASTWARD FROM NRN ONTARIO. SHOWERS FORECAST TO
MOVE INTO NWRN ONTARIO SUNDAY MAY BE OVERDONE, AS FOREIGN GUIDANCE
LOOKS TO BE QUITE A BIT DRIER.

7. HAVE A GREAT DAY, EH?

END/KUHN/OSPC

It's looking pretty darn good! At least, much better than the boring weather we've had the last few weeks.

[Anspray]

should say May 2nd

[DarkSky]

Originally Posted by Anspray

should say May 2nd

Thanks (fixed).

[davefootball123]

http://www.southernontariochasing.ca/sospc.html
My Day 1 and 2 are up. Take a look

[obwan]

things looked ominos here about an hour ago with huge cumulous billowing over head. but just some large rain drops for a couple minutes. Of course it looks like they were larval stage here as severe storm warnings are going up over WNY.

[Storm Chaser]

Good luck to everyone tomorrow. It looks great! Should be a great day!

[davefootball123]

Just put out the new day 1 for tomorrow

[LondonSpartan]

thoughts on today? i hate waking to see so much cloud cover here in the London area - add to that the morning storms (look weak in SW) is this going to kill any real convection for this aft??

[nachos_666]

london ontario. is looking like its trying to conjure up some weather. dark clouds keep rollin in... but moving by just as fast. weather network looks promising for this evening... but we all know how reliant that is. LOL.

[Storm Chaser]

Sunny completely here now. Hrrr has all of southern ontario getting hammered later. Lets hope!