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obwan
09-14-2010, 05:28 AM
Sept is proving as elusive as July and August. those in the Ajax/Oshawa area got clipped yesterday, we here in north niagara had some lightnig early in the morning. But then again it is sept.
Here is the prog for thursday.


...OH VALLEY/LOWER GREAT LAKES...
SURFACE LOW AND ASSOCIATED/TRAILING COLD FRONT WILL CONTINUE MOVING
EWD ACROSS THE MIDWEST/OH VALLEY REGION THIS PERIOD...AS THE
ASSOCIATED MID-LEVEL SHORT-WAVE TROUGH MOVES QUICKLY ACROSS THIS
REGION. THOUGH DESTABILIZATION SHOULD BE LIMITED IN THE PRE-FRONTAL
WARM SECTOR...AMPLE CAPE SHOULD EVOLVE ALONG AND JUST AHEAD OF THE
FRONT TO SUPPORT AN INCREASE IN AFTERNOON STORM COVERAGE/INTENSITY.

AS STORMS DEVELOP...STRONG/GENERALLY WLY FLOW FIELD ALOFT WILL
SUPPORT POTENTIALLY ORGANIZED/FAST-MOVING STORMS. THUS -- POTENTIAL
FOR DAMAGING WINDS APPEARS GREAT ENOUGH TO SUPPORT INTRODUCTION OF
SLIGHT RISK ACROSS THIS REGION. THREAT SHOULD GRADUALLY DIMINISH
OVERNIGHT...THOUGH SOME THREAT MAY LINGER EWD TOWARD SRN NEW ENGLAND
OVERNIGHT.

Derecho
09-14-2010, 12:23 PM
I don't agree with how far north the slight extends. There is no mixing, temperatures should be hovering just above 10C, we'll be northeast of the low, and it'll be cloudy and raining all day.

obwan
09-14-2010, 05:55 PM
we have mixing today in niagara, temps 20C with low level cumulous, even producing showers

davefootball123
09-15-2010, 03:50 PM
...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE OH/TN VALLEY INTO
UPSTATE NY...

...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE SRN HIGH PLAINS...

...OH/TN VALLEY TO SRN NEW ENGLAND...

STRONG HEIGHT FALLS...ON THE ORDER OF 90M/12HR...WILL OVERSPREAD THE
GREAT LAKES INTO THE UPPER OH VALLEY DURING THE DAY AS A PRONOUNCED
SHORTWAVE TROUGH EJECTS ACROSS THE REGION. BY 18Z THIS FEATURE
SHOULD EXTEND FROM LOWER MI INTO IND...COINCIDENT WITH A SHARP SFC
FRONT THAT SHOULD PROGRESS INTO UPSTATE NY-WRN PA-SWWD ALONG THE OH
RIVER BY LATE AFTERNOON. IT APPEARS A NARROW WEDGE OF STRONG
BOUNDARY LAYER HEATING WILL CONTRIBUTE TO ENHANCED
INSTABILITY...MORE THAN ADEQUATE FOR FRONTAL CONVECTION FAIRLY EARLY
IN THE PERIOD. FOCUSED ASCENT SHOULD EASILY CONTRIBUTE TO SQUALL
LINE DEVELOPMENT BY 18Z ACROSS OH WHERE FORECAST SOUNDINGS SUGGEST
STORM MOTIONS COULD EXCEED 40-50KT. DAMAGING WINDS ARE CERTAINLY
POSSIBLE GIVEN THAT SBCAPE IS EXPECTED TO APPROACH 1000 J/KG PRIOR
TO CONVECTIVE OVERTURNING. ONCE DEVELOPED...A STRONGLY FORCED
SQUALL LINE WILL MOVE ACROSS THE OH VALLEY BEFORE GRADUALLY
WEAKENING DUE TO INCREASINGLY HOSTILE BOUNDARY LAYER OVER CNTRL PA.
THERE IS SOME CONCERN THAT A MARKED INCREASE IN LOW LEVEL MOISTURE
DURING THE OVERNIGHT HOURS WILL ENHANCE THE PROSPECT FOR SFC BASED
CONVECTION OVER SRN NEW ENGLAND. IF MID-UPPER 60S DEW POINTS DO IN
FACT RETURN TO THIS REGION A SLIGHT RISK WILL CERTAINLY BE WARRANTED
AS VERY STRONG FLOW JUST OFF THE SFC WOULD ENHANCE THE DAMAGING WIND
POTENTIAL FOR ANY STORMS THAT DEVELOP DURING THE 06-12Z TIME FRAME.
THIS REGION WILL BE MONITORED FOR A POSSIBLE UPGRADE.
Looking good to about Hamilton guy with 15% and 30% just farther south which has a chance of being extended. 5% extends to just north of kw to king city area

obwan
09-15-2010, 08:25 PM
forecast for Niagara Falls NY'

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE BUFFALO NY
356 PM EDT WED SEP 15 2010

NYZ001>005-010>014-019>021-085-162000-
NIAGARA-ORLEANS-MONROE-WAYNE-NORTHERN CAYUGA-NORTHERN ERIE-GENESEE-
WYOMING-LIVINGSTON-ONTARIO-CHAUTAUQUA-CATTARAUGUS-ALLEGANY-
SOUTHERN ERIE-
356 PM EDT WED SEP 15 2010

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF WESTERN AND NORTH
CENTRAL NEW YORK.

.DAY ONE...THIS AFTERNOON AND TONIGHT.

THE PROBABILITY OF WIDESPREAD HAZARDOUS WEATHER IS LOW.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY.

A POTENT LOW PRESSURE SYSTEM WILL TRACK FROM LOWER MICHIGAN
EASTWARD ALONG OR JUST SOUTH OF LAKE ONTARIO DURING THURSDAY...
BEFORE EXITING OUT ACROSS EASTERN NEW YORK AND NEW ENGLAND
THURSDAY NIGHT. THIS WILL ALLOW A COLD FRONT TO PLOW ACROSS MUCH
OF WESTERN NEW YORK THURSDAY AFTERNOON AND EVENING...AND WITH AN
UNSTABLE AIRMASS AND UNUSUALLY STRONG LOW LEVEL WINDS IN
PLACE...STRONG TO SEVERE THUNDERSTORMS COULD DEVELOP.

WHILE GUSTY THUNDERSTORMS WILL BE POSSIBLE AT JUST ABOUT ANYTIME
DURING THURSDAY...THE HIGHEST CHANCE FOR SEVERE WEATHER WILL COME
DURING THURSDAY AFTERNOON AND EVENING. THE GREATEST SEVERE WEATHER
THREAT FROM ANY SUCH STORMS WILL BE FROM DAMAGING STRAIGHT LINE
WINDS.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE NEEDED

davefootball123
09-15-2010, 09:55 PM
Obwan check out my site for the 1000pm update. Text is done by me and maps done by storm chaser. We do not use SPC we use the models lol and i do my own texts. www.southernontarioweather.ca

Derecho
09-15-2010, 11:35 PM
The most favourable areas of parameters have all shifted south on the latest SREF. The position of the low is going to hamper even an isolated threat of an actual severe thunderstorm anywhere north of Lake Erie. Favourable CAPE's have all shifted south, any part of southern Ontario proper look to struggle to even peak at 500 j/kg.

I mentioned mixing above on an earlier post. I meant parameters on that one, lol. It was late when I typed that.