SWOMCD
SPC MCD 260721
NYZ000-260945-
MESOSCALE DISCUSSION 2018
NWS STORM PREDICTION CENTER NORMAN OK
0221 AM CDT WED SEP 26 2007
AREAS AFFECTED...PORTIONS NRN NY.
CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY
VALID 260721Z - 260945Z
THROUGH APPROXIMATELY 11Z...TSTMS INITIALLY OVER SERN ONT AND LAKE
ONT ARE EXPECTED TO MOVE EWD ACROSS ERN LAKE ONT AND ST LAWRENCE
VALLEY INTO PORTIONS NRN NY...N OF ROC-SYR-GFL LINE. ALTHOUGH
RELATIVELY STABLE LOW LEVEL AIR MASS SHOULD PRECLUDE ORGANIZED SVR
WIND POTENTIAL...SOME DAMAGING GUSTS MAY REACH SFC ESPECIALLY INVOF
SERN/ERN SHORE OF LAKE ONT...AND INVOF ST LAWRENCE VALLEY.
MAIN BAND OF TSTMS WAS EVIDENT OVER SERN ONT AT 7Z...FROM ABOUT 50
WNW ART TO 75 NW ART...MOVING ENE 50 KT. MORE ISOLATED/DISCRETE
ACTIVITY EXTENDED SWD TO WAYNE COUNTY LAKE SHORE. BOUNDARY LAYER
AHEAD OF THESE TSTMS WILL BE MOST FAVORABLE FOR SUPPORTING
PENETRATION OF DOWNDRAFT WINDS TO SFC IN ST LAWRENCE VALLEY AND OVER
IMMEDIATE LAKE REGION...WHERE THETAE IS HIGHEST. MODIFIED RAOBS AND
RUC FCST SOUNDINGS SUGGEST OPTIMALLY MOIST AIR MASS -- WITH SFC
TEMPS MID 70S F AND DEW POINTS UPPER 60S F -- STILL IS CAPPED FOR
SFC-BASED LIFTED PARCELS...RESIDING AT BASE OF STABLE LAYER.
NOCTURNAL/DIABATIC SFC COOLING SHOULD MAINTAIN THAT STATE...HOWEVER
ROUGHLY 2 KM DEEP LAYER OF RELATIVELY DRY/WELL-MIXED AIR EXISTS
BETWEEN NEAR-SFC STABLE LAYER AND CONVECTION-BEARING REGION.
500-1000 J/KG MUCAPE SHOULD BE ROOTED IN ELEVATED INFLOW REGION OF
TSTMS. GUSTS THAT ARE EXPELLED BY CONVECTION MOVING OVER THAT DRY
ZONE MAY ACCELERATE THROUGH IT ENOUGH TO PENETRATE SHALLOW NEAR-SFC
LAYER WHILE REMAINING STG. THOUGH SUCH GUSTS SHOULD REMAIN BELOW 50
KT MEASURED-SVR CRITERIA...BREAKAGE/TOPPLING OF WEAK TREES OR MINOR
DAMAGE TO STRUCTURES CANNOT BE RULED OUT. AIR MASS WILL CONTINUE TO
BECOME PROGRESSIVELY MORE STABLE WITH EWD EXTENT ACROSS REMAINDER
NRN NY...THOUGH SOME STG CONVECTIVE WINDS MAY AFFECT MAINLY WRN
SLOPES IN HIGHER ELEVATIONS OF ADIRONDACKS.
.EDWARDS.. 09/26/2007
..PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...BTV...ALY...BUF...
43267697 43497687 43737638 44137642 44327602 44517577
44797539 44937505 45007481 45007373 44457401 43907477
43277680
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
To unsubscribe from WX-STORM send e-mail to LISTSERV@PO.UIUC.EDU with
"unsub wx-storm" in the body of your message. For more information write cnovy@cox.net.
No comments:
Post a Comment