STORM PREDICTION CENTER...NWS/NCEP...NORMAN OK 
DAY 1 CONVECTIVE OUTLOOK...REF AWIPS GRAPHIC PGWE46 KWBC. 

VALID 011200Z - 021200Z 

THERE IS A MDT RISK OF SVR TSTMS ACROSS NERN PA...NRN NJ...SERN
NY...CT...RI...MA...SRN VT...SRN NH...AND EXTREME SRN ME.  THE MDT RISK
AREA IS TO THE RIGHT OF A LINE FROM 10 SSE JFK ABE 30 ENE IPT 10 NNW GFL
20 N LCI PWM. 
THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 25 SE SUX
50 N LAA 20 E COS 20 ESE CPR 35 SW SHR LVM 35 S GTF 45 NE GTF 65 WNW GGW
35 SE OLF 40 NE Y22 10 NE ABR 25 NNE ATY 15 NNW OTG 25 SE SUX. 

THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 30 N ORF
55 ENE DAN 25 S PSK 40 SSW BMG 35 SW HUF 20 SE CMI 30 NNE LAF 25 NE FWA
20 NE TOL. 

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM IPL TRM 50 ESE DAG 35 SSE
LAS 45 NNE IGM 15 SSE GCN 55 E GCN 65 ESE PGA 30 WSW 4BL 45 NE 4BL 30 SW
ASE EGE 45 ESE RKS 50 NW LND 15 SSW WEY 30 SSW DLN 45 N 27U 30 SE S06 90
ENE 63S ...CONT... 70 NNW TVF 40 W BRD 40 ENE RWF 20 NNW FOD 60 SW FOD
40 SW DSM 25 S OTM 25 NE PIA 25 SW SBN 20 SSW JXN 30 NE MTC. 

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 25 W JLN 30 NNE CNU 10 SW
MHK 20 W RSL 20 NE GCK 65 S LBL 30 SW CDS 40 NNE ABI 20 NE MWL 55 E OKC
25 W JLN. 

...SYNOPSIS... 

MID-LEVEL PATTERN IS FORECAST TO BECOME SOMEWHAT MORE AMPLIFIED THIS
PERIOD AS STRONG ERN TROUGH DEEPENS AND MOVES ACROSS THE NERN CONUS.
THIS TROUGH AND ASSOCIATED VERY STRONG WIND FIELD WILL LIKELY SUPPORT A
POTENTIALLY SIGNIFICANT WIND EVENT FOR MUCH OF NEW ENGLAND AND PARTS OF
THE MID-ATLANTIC REGION.  

MEANWHILE...UPPER RIDGE CENTERED OVER THE FOUR CORNERS REGION WILL
EXPAND NWWD AS SHORTWAVE TROUGH TOPS THE RIDGE IN MT AND MOVES SEWD INTO
THE PLAINS. 

AT THE SURFACE...THE MAIN FEATURE WILL BE THE COLD FRONT ASSOCIATED WITH
THE ERN TROUGH.  THIS FRONT IS INITIALLY FORECAST TO LIE IN AN ARC SOUTH
OF 1030 SURFACE HIGH...FROM ERN ONTARIO SWWD ACROSS THE ERN GREAT LAKES
REGION INTO THE MO RIVER VALLEY...AND THEN NWWD ACROSS THE CENTRAL HIGH
PLAINS INTO MT.  BY THE END OF THE PERIOD...THIS FRONT IS FORECAST TO
MOVE OFF THE NEW ENGLAND COAST...AND SHOULD LIE ROUGHLY W-E FROM NC
ACROSS THE TN AND MID MS VALLEY INTO OK...AND THEN NNWWD ACROSS THE HIGH
PLAINS INTO SASKATCHEWAN. 

...NERN CONUS... 

SIGNIFICANT SEVERE WEATHER EVENT IS FORECAST FOR THE REGION THIS PERIOD.
COLD FRONT IS EXPECTED TO MOVE EWD ACROSS THE ERN GREAT LAKES EARLY IN
THE PERIOD...AND WILL THEN MOVE EWD INTO NEW ENGLAND AND SEWD ACROSS THE
OH VALLEY DURING THE AFTERNOON / EVENING. ALTHOUGH AIRMASS AHEAD OF THE
FRONT WILL REMAIN QUITE MOIST WITH DEWPOINTS IN THE 60S TO NEAR 70 OVER
NEW ENGLAND AND THE OH VALLEY AND INTO THE LOW 70S IN THE DELMARVA
REGION...WEAK LOW- TO MID-LEVEL LAPSE RATES ACROSS THE REGION /AROUND 6
C/KM/ AND SOME CLOUD COVER WILL LIMIT AVAILABLE INSTABILITY.
NONETHELESS...SOME DAYTIME HEATING AND AMOUNT OF MOISTURE WILL LIKELY
YIELD SURFACE-BASED CAPE IN THE 1000 TO 2000 J/KG RANGE.  SCATTERED TO
ISOLATED THUNDERSTORMS WILL LIKELY BE ONGOING AT THE BEGINNING OF THE
PERIOD ACROSS THIS REGION...AND WITH STRENGTH OF UPPER TROUGH AND
LOW-LEVEL FORCING ALONG COLD FRONT...STORMS SHOULD INCREASE ALONG AND
AHEAD OF BOUNDARY BY EARLY AFTERNOON.  STORMS SHOULD RAPIDLY EVOLVE INTO
A SIGNIFICANT SQUALL LINE...WITH PERHAPS A FEW ISOLATED SUPERCELLS
DEVELOPING AHEAD OF THE LINE DURING THE AFTERNOON. 

ALTHOUGH WIND SHEAR IS FORECAST TO BE GENERALLY UNIDIRECTIONAL... WINDS
THROUGH A DEEP LAYER ARE FORECAST TO BE QUITE STRONG -- PARTICULARLY
FROM PA NWD...WITH AN 80 KT WLY MID-LEVEL JET STREAK FORECAST IN CENTRAL
NY BY EVENING.  AS A RESULT...EXPECT A THREAT FOR SIGNIFICANT WIND
DAMAGE ACROSS THIS REGION AS STORMS ORGANIZE AHEAD OF COLD FRONT.  THERE
WILL ALSO LIKELY BE A SECONDARY THREAT FOR HAIL...AND POSSIBLY A FEW
TORNADOES -- PARTICULARLY WITH ANY SUPERCELLS WHICH MAY DEVELOP AHEAD OF
MAIN CONVECTIVE LINE.  A COUPLE OF BRIEF TORNADOES WILL ALSO BE POSSIBLE
WITH ANY BOWING SEGMENTS OF THE LINE.  STORMS WILL LIKELY MOVE OFF THE
ATLANTIC COAST SHORTLY AFTER MIDNIGHT.  

..GOSS.. 07/01/01



STORM PREDICTION CENTER...NWS/NCEP...NORMAN OK 
DAY 1 CONVECTIVE OUTLOOK...REF AWIPS GRAPHIC PGWE46 KWBC. 

VALID 011300Z - 021200Z 

THERE IS A MDT RISK OF SVR TSTMS THIS AFTERNOON AND EVENING ACROSS SRN
OH...NRN WV...NRN MD...SERN PA...NWRN NJ...SERN NY...CT...MA... RI...AND
SRN NH AND VT...TO THE RIGHT OF A LINE FROM EWR 20 S MRB 20 SSW EKN 40
SE LUK 20 W LUK 25 SE CMH 30 S DUJ 20 SW BGM GFL 10 SSE LEB 25 E LCI EWB
EWR. 

THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 50 N MOT
40 NE JMS 30 SSW AXN 10 E FRM 25 S ALO 45 ESE MMO 40 E TOL ...CONT... 35
SSW WAL 20 SE LYH 30 NW TRI 10 N PAH 15 WNW SZL 15 S CNK 40 S MCK 25 S
LIC 45 S DGW 30 NE WRL 35 NNW HVR. 

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 80 NNW GFK 15 SW STC 45
SSW LSE 30 E JVL 25 WSW AZO 10 ESE DTW ...CONT... 30 SW FHU 20 NNE PRC
30 NNW EED 55 SW P38 50 NE ELY 25 SE TWF 45 N FCA. 

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 45 ENE BGS 20 SE DUA 45
NNE LIT 30 WNW POF 45 SSE SZL 10 SE EMP 20 E RSL 55 SW HLC 50 S GLD 25
SW LAA 25 S CAO 45 NE HOB 45 ENE BGS. 

...SYNOPSIS... 

POWERFUL UPR TROUGH AND ASSOCIATED STRONG SFC COLD FRONT WILL SWEEP
THROUGH THE ERN GREAT LAKES REGION THIS MORNING AND THROUGH NY/PA AND
NEW ENGLAND THIS AFTERNOON AND TONIGHT. SUBSTANTIAL MID LEVEL HEIGHT
FALLS OF OVER 100 M IN 12-HOURS ACROSS NY AND NRN NEW ENGLAND WILL
SUPPORT VIGOROUS UPWARD VERTICAL MOTION AHEAD OF AND ALONG THE FRONT.
MOIST AND UNSTABLE AIRMASS OVER THE REGION WILL AID DEVELOPMENT OF ONE
OR MORE SQUALL LINES WITH RAPID CELL MOTION AND 50-80 KT MID LEVEL FLOW
RESULTING IN WIDESPREAD DAMAGING WIND POTENTIAL. 

...NORTHEAST... 

LATEST SFC ANALYSIS AND RADAR TRENDS SUGGESTED COLD FRONT WAS MOVING
ESEWD ACROSS SRN LOWER MI AND SRN LAKE HURON AT 30 KT. A PREFRONTAL
TROUGH WAS SITUATED FROM LAKE ERIE INTO CNTRL NY AND TSTMS WERE
INCREASING COINCIDENT WITH THE PREFRONTAL TROUGH AND INSTABILITY AXIS
WHERE CAPE WAS CURRENTLY AROUND 500-1000 J/KG. SFC TEMPERATURES WERE
ALREADY IN THE 70S F WITH 65-70 F DEWPOINTS ACROSS MUCH OF THE REGION.
VISIBLE SATELLITE IMAGERY SUGGESTED THAT SFC HEATING WILL BE STRONGEST
ACROSS SERN NY INTO MA AND SRN NH. INITIAL LINE OF CONVECTION AND
RESULTANT CIRRUS SHIELD MAY INHIBIT INSTABILITY OVER SOME AREAS BUT
MAGNITUDE OF FORCING AND POTENTIAL MID LEVEL DRY INTRUSION LATER TODAY
WILL TEND TO OFFSET WEAKER LAPSE RATES AND INSTABILITY CURRENTLY IN
PLACE. EXPECT LOCATIONS WITH MARGINAL INSOLATION TO REACH CAPE VALUES OF
1500-2000 J/KG PRIOR TO TSTM DEVELOPMENT. 

PREFRONTAL LINE OF STORMS SHOULD INCREASE IN INTENSITY AND ORGANIZATION
AS GREATER INSTABILITY IS REALIZED. A SECOND LINE OF SVR STORMS MAY ALSO
FORM ALONG THE SYNOPTIC FRONT. DEEP LAYER UNIDIRECTIONAL SHEAR WILL
INCREASE SIGNIFICANTLY AS 75-80 KT MID LEVEL WIND MAX ROTATES ACROSS
NY/PA AND NEW ENGLAND THROUGH THIS EVENING. MID LEVEL DRY INTRUSION
ALONG THE COLD FRONT WILL ALSO ENHANCE CONVECTIVE DOWNDRAFTS AND COLD
POOL GENERATION WITH BOW ECHO COMPLEX EXPECTED TO MOVE ACROSS MUCH OF
ERN NY AND NEW ENGLAND DURING TIME OF MAXIMUM DIURNAL DESTABILIZATION.
WHILE STRAIGHT LINE WIND DAMAGE AND SOME HAIL ARE EXPECTED TO BE THE
PRIMARY THREATS... BACKED LOW LEVEL FLOW WITHIN N-S VLYS MAY RESULT IN
SUFFICIENT LOW LEVEL SHEAR FOR ISOLATED TORNADOES. 

...OH VALLEY... 

THERMALLY DIRECT CIRCULATION WITHIN RIGHT ENTRANCE REGION OF STRONGLY
CURVED UPR JET WILL SUPPORT LARGE SCALE ASCENT AND LOW LEVEL CONVERGENCE
ALONG THE COLD FRONT AS IT DROPS SWD ACROSS IND/OH/WRN PA AND WV THIS
AFTERNOON AND EVENING. RICH LOW LEVEL MOISTURE /DEWPOINTS IN THE UPR 60S
F/ AND HEATING AHEAD OF THE FRONT WILL CONTRIBUTE TO VERY UNSTABLE
CONDITIONS WITH CAPE EXCEEDING 2000 J/KG IN SOME AREAS. THIS INSTABILITY
WILL SUPPORT INTENSE UPDRAFTS WITH SLY LOW LEVEL STORM RELATIVE FLOW
RESULTING IN RAPID SSEWD STORM PROPAGATION/LINE DEVELOPMENT. DEEP WLY
UNIDIRECTIONAL SHEAR MAY ALLOW STORMS TO ORGANIZE INTO SMALL SCALE BOWS
WITH GREATER POTENTIAL FOR WIND DAMAGE. IN ADDITION...DEGREE OF
INSTABILITY WILL FAVOR LARGE HAIL. 

..CARBIN.. 07/01/01



STORM PREDICTION CENTER...NWS/NCEP...NORMAN OK 
DAY 1 CONVECTIVE OUTLOOK...REF AWIPS GRAPHIC PGWE46 KWBC. 

VALID 011630Z - 021200Z 

THERE IS A MDT RISK OF SVR TSTMS FOR SE OH...NW WV...MUCH OF PA...SE
NY...CT...RI.. MA...SRN VT...NH...AND WRN ME TO THE RIGHT OF A LINE FROM
20 NE JFK ILG 45 SSE LBE 25 N HTS 20 SSW CMH 20 N ZZV 25 SW DUJ 20 SW
BGM 10 N LEB 40 WSW 3B1 15 NNW AUG 15 NE PVD 20 NE JFK. 

THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 70 NNE ISN
40 NW ABR 35 SSW OTG 45 SE OMA 25 SW FNB 40 WSW CNK 10 SSE GLD 35 ESE
DEN 15 N LAR 40 WNW SHR 30 WSW 3HT 45 ENE CTB. 

THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 25 ESE ORF
30 W DAN 50 WNW TRI 25 NW HOP 20 ENE MVN 15 E DEC 45 NNW MFD. 

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 70 NE DVL 10 NNE AXN 45
WSW ALO 30 NNE PIA 35 NW LAF 15 ENE TOL ...CONT... 85 S GBN 70 NNW GBN
35 SSW LAS 45 ENE DRA 60 SE ELY 30 N SUN 45 N FCA. 

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 50 NE BGS 40 ESE OKC 40 E
HRO 40 NNE UNO 50 WNW TBN 25 SSW TOP 25 W SLN 55 SW HLC 55 ENE LAA 40
NNW EHA 20 SSE DHT 60 ENE HOB 50 NE BGS. 

...OH VALLEY TO NEW ENGLAND... 

A VIGOROUS MID LEVEL TROUGH/70-80 KT SPEED MAX WILL MOVE ESEWD OVER
NY/PA/NEW ENGLAND THIS AFTERNOON AND TONIGHT...WHILE A DEEP SURFACE
CYCLONE DEVELOPS OVER QUEBEC.  IN ASSOCIATION WITH THE MID LEVEL
TROUGH/SURFACE LOW...A PRE-FRONTAL TROUGH AND SURFACE COLD FRONT WILL
MOVE SWD ACROSS THE OH VALLEY AND EWD ACROSS NY/NEW ENGLAND BY TONIGHT.
BOUNDARY LAYER DEWPOINTS ARE GENERALLY IN THE MID-UPPER 60S IN THE WARM
SECTOR...AND DAYTIME HEATING WILL ALLOW SBCAPE VALUES TO INCREASE TO
2000-3000 J/KG.  AT THE SAME TIME...MEAN WINDS WILL INCREASE TO 45-55 KT
OVER THE WARM SECTOR FROM W TO E...RESULTING IN RELATIVELY FAST STORM
MOTIONS AND THE POTENTIAL FOR WIDESPREAD DAMAGING WINDS WITH STORMS
ALONG AND SE OF THE COLD FRONT. 

..THOMPSON.. 07/01/01



STORM PREDICTION CENTER...NWS/NCEP...NORMAN OK 
DAY 1 CONVECTIVE OUTLOOK...REF AWIPS GRAPHIC PGWE46 KWBC. 

VALID 012000Z - 021200Z 

THERE IS A MDT RISK OF SVR TSTMS THE REMAINDER OF THIS AFTERNOON OVER
PORTIONS NJ...NRN DE...NRN MD...NRN VA...NRN WV...EXTREME SERN OH...SERN
PA...SERN NY...MA...CT AND RI...AND EXTREME SRN NH...TO THE RIGHT OF A
LINE FROM ACY DOV 35 S MRB EKN UNI 35 SW AOO MSV EEN PSM. 

THERE IS A SLGT RISK OF SVR TSTMS ELSEWHERE TO THE RIGHT OF A LINE FROM
30 SE ORF DAN BWG 25 NW HOP MVN SLO MTO HUF ZZV LBE IPT BGM ART 25 WSW
MSS. 

THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 60 NNE GGW
ISN P24 BIS MBG MHE 30 NE SUX 45 ENE OMA FNB CNK HLC 35 S GLD LAA LHX
PUB COS DEN CYS CPR WRL 10 N LVM 30 SE GTF 35 N HVR. 

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 75 SSW GBN 60 NW GBN EED
10 NW LAS P38 20 SSW ELY 45 SE EKO 40 S BOI 55 WSW MSO 50 NNE FCA
...CONT... 75 NE MOT FAR RWF OTM PIA MFD CAK FKL ROC. 

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 45 ESE OKC MKO 35 ESE HRO
UNO TBN 25 SW OJC SLN RSL 40 WNW GCK 10 ESE DHT MAF 45 ESE OKC. 

--- SYNOPSIS --- 

UPPER AIR PATTERN OVER CONUS FEATURES INTENSE SHORTWAVE TROUGH
AMPLIFYING AS IT MOVES EWD ACROSS SERN ONT/SWRN QUE/ERN GREAT LAKES
REGION...SLOWLY STRENGTHENING 4-CORNERS AREA ANTICYCLONE...AND SLOWLY
WEAKENING TROUGH OVER ARKLATEX THAT WILL CONTINUE MOVING SWWD.  STRONG
SURFACE COLD FRONT ASSOCIATED WITH NERN TROUGH -- ANALYZED FROM NERN NY
SWWD ACROSS CENTRAL OH TO NRN MO/SRN NEB. FRONT THEN BECOMES
QUASISTATIONARY TO WARM NWWD ACROSS WRN NEB...NERN WY TO N-CENTRAL MT.
FRONT IS FORECAST TO MOVE SEWD TO NEAR VA/NC BORDER...TN AND SRN MO BY
END OF PERIOD...AND DRIFT GENERALLY NEWD FARTHER W. 

--- NERN STATES --- 

SEVERAL SEVERE CONVECTIVE BANDS AND LINE SEGMENTS WILL CONTINUE MOVING
ACROSS REGION FROM NEW ENGLAND SWWD TOWARD SRN OH AND CENTRAL/SRN
INDIANA OVER NEXT SEVERAL HOURS...BEFORE NEW ENGLAND ACTIVITY MOVES
OFFSHORE.  SEVERE OUTFLOWS WITH WIND DAMAGE WILL CONTINUE...ALONG WITH
OCCASIONAL LARGE HAIL.  REF WWS 489-492... ALONG WITH ASSOCIATED
MESOSCALE DISCUSSIONS AND STATUS MESSAGES... FOR LATEST NOWCAST AND
THREAT CLEARANCE INFO.  CONSOLIDATED BELT OF STRONG-SEVERE TSTMS WILL
SAG SWD THIS EVENING ALONG/AHEAD OF FRONT AS CELLS MOVE EWD IN AN
ENVIRONMENT OF 50-70 KT MID LEVEL FLOW...MID 60S-LOW 70S SURFACE DEW
POINTS...AND ONLY SLOWLY COOLING SURFACE TEMPS.  

..EDWARDS.. 07/01/01