Severe Storm Outlook Narrative (AC)
Issued by NWS

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000
ACUS01 KWNS 231301
SWODY1
SPC AC 231259

DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0759 AM CDT WED JUL 23 2014

VALID 231300Z - 241200Z

...THERE IS A SLGT RISK OF SVR TSTMS FROM ERN WA EWD INTO THE NRN
PLNS...

...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF THE NORTHEAST...

...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF THE OZARKS...

...SUMMARY...
SEVERE STORMS WITH MAINLY LARGE HAIL ARE LIKELY FROM PARTS OF
WASHINGTON EASTWARD INTO THE NORTHERN GREAT PLAINS THIS AFTERNOON
INTO TONIGHT. LARGE HAIL ALSO IS POSSIBLE OVER THE BLACK HILLS
REGION. STORMS WITH MARGINALLY SEVERE WINDS MAY OCCUR FROM EASTERN
NEW YORK INTO NEW ENGLAND DURING THE AFTERNOON...AND ISOLATED SEVERE
STORMS MAY OCCUR FROM THE LOWER OHIO VALLEY SOUTHWESTWARD ACROSS THE
OZARKS.

...SYNOPTIC SETUP...
STRONG RIDGE WILL REMAIN STNRY OVER THE SRN AND CNTRL RCKYS THIS
PERIOD AS POTENT NE PAC LOW/TROUGH ACCELERATES E/NE INTO SRN BC/ERN
WA. E OF THE RIDGE...EXISTING TROUGH WILL AMPLIFY OVER THE GRT LKS
AND OH/TN VLYS...STRENGTHENING ASSOCIATED WSW FLOW OVER THE NERN
STATES.

AT LWR LVLS...A STRENGTHENING COLD FRONT WILL ADVANCE ENE TO THE
ID-WA-ORE BORDER BY THIS EVE...AND INTO WRN MT EARLY THU...AS
MOIST...SELY FLOW AND LEE CYCLONE STRENGTHEN OVER THE NRN HIGH PLNS.

ELSEWHERE...A COLD FRONT WILL ADVANCE SE ACROSS NEW ENGLAND...THE
LWR GRT LKS...AND THE MID-ATLANTIC REGION LATER TODAY/TNGT...WHILE
ITS WRN EXTENT BECOMES NEARLY STNRY OVER THE LWR MS VLY...THE SRN
OZARKS AND THE SRN PLNS.

...ERN WA/NRN ID EWD INTO THE NRN PLNS TODAY/TNGT...
WA/ORE COLD FRONT SHOULD SERVE AS A FOCUS FOR STRONG STORMS LATER
TODAY AS IT AND ASSOCIATED SFC WAVE TRACK ENE INTO ID THIS EVE...AND
INTO WRN MT LATER TNGT. STRONG SFC HEATING AND MID-LVL
COOLING/ASCENT AHEAD OF ASSOCIATED UPR TROUGH WILL AID STORM
DEVELOPMENT...WITH AMPLE SHEAR/BUOYANCY FOR SUSTAINED
STORMS/SUPERCELLS. THESE WILL BE CAPABLE OF SVR WIND AND HAIL.

FARTHER E...A SEPARATE AREA OF SVR STORMS MAY ARISE THIS AFTN AND
EVE OVER CNTRL AND NRN MT...ON WRN FRINGE OF LOW-LVL SELY FLOW
ASSOCIATED WITH DEEPENING LEE LOW/TROUGH. SFC DEWPOINTS WILL RISE
INTO THE 50S AND LOW 60S F...ENHANCING BUOYANCY GIVEN STRONG SFC
HEATING AND STEEP MID-LVL LAPSE RATES. STRONG...VERTICALLY-VEERING
WIND PROFILES WILL YIELD SIZABLE/CURVED HODOGRAPHS FAVORABLE FOR
SUPERCELLS WITH LARGE HAIL/PERHAPS VERY LARGE/...ALONG WITH DAMAGING
WINDS...AND TORNADOES.

THE NRN MT STORMS MAY MERGE INTO A CLUSTER OR TWO LATER THIS EVE
THAT MOVES EWD INTO NE MT WITH A CONTINUING RISK FOR SVR. AROUND THE
SAME TIME...AN ADDITIONAL AREA OF STORMS MAY FORM OVER WRN ND SEWD
INTO CNTRL SD AS WAA/MOISTURE TRANSPORT STRENGTHEN DOWNSTREAM FROM
ACCELERATING WA/ORE TROUGH. DEEP EML AND AVAILABILITY OF RICH
MOISTURE SUGGEST THAT THESE ELEVATED STORMS WILL HAVE THE POTENTIAL
FOR LARGE HAIL INTO THE OVERNIGHT.

...BLACK HILLS/ERN WY THIS AFTN/EVE...
WEAKLY UPSLOPE SSELY FLOW AND SFC HEATING MAY INITIATE ISOLD SVR
STORMS LATE THIS AFTN OVER ERN WY/WRN SD. WHILE DEEP SHEAR WILL BE
LESS THAN THAT IN MT...IT WILL BE SUFFICIENT FOR SUPERCELLS GIVEN
VERTICALLY VEERING WINDS. ALTHOUGH SETUP DOES NOT APPEAR AS
FAVORABLE AS YESTERDAY/S...A CONDITIONAL RISK FOR SVR HAIL AND
LOCALLY DMGG WIND WILL EXIST WITH ANY STORMS THAT DO FORM.

...ERN NY INTO NEW ENGLAND...
WSWLY UPR FLOW AND ASCENT WILL STRENGTHEN AHEAD OF APPROACHING COLD
FRONT TODAY...WITH DEEP SHEAR INCREASING TO AROUND 30 KTS. WHILE
RICHER MOISTURE WILL REMAINED CONFINED TO POINTS WELL S INVOF
STALLED FRONT OVER CAROLINA CST...WITH MODERATE HEATING SUFFICIENT
INSTABILITY SHOULD DEVELOP FOR SCTD STRONG AFTN STORMS WITH LOCALLY
DMGG WIND GUSTS. SMALL HAIL ALSO MAY OCCUR.

...LWR OH VLY SW INTO OZARKS THIS AFTN/EVE...
SOMEWHAT UNUSUAL PATTERN IN PLACE ACROSS THIS REGION TODAY...WITH
STRENGTHENING DEEP NELY FLOW ON SE SIDE OF RCKYS UPR RIDGE...MAY
SUPPORT THE DEVELOPMENT AND SWWD MOTION OF A STRONG TO POSSIBLY SVR
MCS OVER PARTS OF SRN MO...AR...AND SE OK LATER TODAY. STRONG
HEATING WILL OCCUR BENEATH 30-40 KT UNIDIRECTIONAL 700-500 MB FLOW
ON SRN FRINGE OF EML. COUPLED WITH COINCIDENT CORRIDOR OF HIGH /1.75
INCH/ PW...SETUP MAY YIELD A CONDITIONAL RISK FOR SW-PROPAGATING
LINE SEGMENTS CAPABLE OF DMGG WIND. THE 12Z RAOB DATA AT SGF AND LIT
SUPPORT THIS IDEA...WITH WEAK CIN AT LIT AND DEEP/STOUT EML AT SGF.
IF STORMS DO INDEED FORM...THEY MOST LIKELY WOULD INITIATE EITHER
ALONG COLD FRONT SETTLING S THROUGH THE OZARKS...OR WITH ISENTROPIC
ASCENT ON SRN SIDE OF EML .

..CORFIDI/MOSIER.. 07/23/2014



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