SPC AC 230806
DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0206 AM CST TUE DEC 23 2003
VALID 241200Z - 251200Z
GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 25 WNW BLI 30 NNE SEA
20 N PDX 45 ESE EUG 20 NNW MFR CEC.
GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM AQQ 20 SSW MGR 35 SW
CLT 20 SW LYH 15 SSE MRB 20 SSE IPT 35 NE BGM 40 S SLK 10 NNE MPV 20
W BHB.
...NO SVR TSTM AREAS FORECAST...
...SYNOPSIS...
AMPLIFIED LARGE-SCALE PATTERN WILL EXIST ON THE DAY 2 PERIOD WITH
THE PRIMARY FEATURE OF INTEREST BEING DEEP...CLOSED MID-LEVEL
CIRCULATION WHICH WILL MOVE EWD/NEWD FROM THE CNTRL GREAT LAKES INTO
THE ST. LAWRENCE VALLEY. MEAN TROUGH ASSOCIATED WITH THIS CLOSED LOW
WILL BECOME NEGATIVELY-TILTED AT THIS TIME AS VORTICITY MAX AND
ASSOCIATED UPPER-LEVEL JET STREAK EJECT NEWD ACROSS THE SERN U.S. TO
OFF THE MIDDLE ATLANTIC COAST.
IN THE LOW-LEVELS...PRIMARY SURFACE CYCLONE INITIALLY IN THE LEE OF
THE CNTRL APPALACHIANS WILL MOVE/DEVELOP NWD ALONG ATTENDANT
BAROCLINIC INTO SRN QUEBEC BY THURSDAY MORNING. TRAILING COLD FRONT
WILL CONCURRENTLY PUSH SEWD THROUGH THE MIDDLE ATLANTIC
STATES...SERN U.S. AND FL.
...ERN NC/SERN VA...
SHOWERS AND TSTMS WILL LIKELY BE ONGOING AT THE START OF THE
FORECAST PERIOD IN WAA/ISENTROPIC ASCENT ZONE WITHIN WARM CONVEYOR
BELT AHEAD OF APPROACHING UPPER-LEVEL TROUGH. THIS ACTIVITY WILL
SHIFT NEWD INTO THE ATLANTIC DURING THE MORNING HOURS AS
INTENSIFYING SLY LLJ DEVELOPS NWD ALONG THE ATLANTIC COAST.
STRONG DYNAMIC FORCING AHEAD OF NEGATIVELY-TILTED TROUGH COUPLED
WITH MODEST AMOUNTS OF BOUNDARY-LAYER MOISTURE /I.E. DEWPOINTS OF
55-60F/ SHOULD CONTRIBUTE TO A WEAKLY UNSTABLE AIRMASS ACROSS THE
DISCUSSION AREA FROM LATE MORNING THROUGH THE AFTERNOON HOURS WITH
ADDITIONAL TSTM DEVELOPMENT POSSIBLE ALONG ADVANCING COLD FRONT.
ALTHOUGH THE WEAK INSTABILITY WILL TEND TO REDUCE THE OVERALL SEVERE
WEATHER THREAT...FAVORABLY STRONG TROPOSPHERIC WIND FIELDS WILL
SUPPORT THE POTENTIAL FOR A FEW ORGANIZED STORMS WITH ISOLATED
DAMAGING WINDS/LARGE HAIL.
...FL...
A LINE OF TSTMS MAY INITIALLY BE IN PROGRESS ALONG SURFACE COLD
FRONT OVER THE ERN FL PNHDL WITHIN WEAKLY UNSTABLE ENVIRONMENT.
AIRMASS SHOULD TEND TO DESTABILIZE THROUGH THE DAY AHEAD OF
FRONT...SUPPORTING ADDITIONAL TSTM ACTIVITY ACROSS THE PENINSULA.
PRIMARY FACTORS MITIGATING SEVERE WEATHER POTENTIAL APPEAR TO BE
VEERED LOW-LEVEL WINDS ACROSS THE WARM SECTOR /EFFECTIVELY
DIMINISHING LOW-LEVEL CONVERGENCE/ AND GENERALLY WEAK LARGE-SCALE
FORCING FOR ASCENT.
..MEAD.. 12/23/2003
...NOTICE...
FOR USERS DECODING THE POINTS PARAGRAPH HEREIN...LATITUDE AND
LONGITUDE POINTS FOR THE CATEGORICAL AND PROBABILISTIC OUTLOOK
GRAPHICS ALSO ARE LOCATED IN A SEPARATE PRODUCT UNDER THE WMO
HEADINGS WUUS01 PTSDY1...WUUS02 PTSDY2...AND WUUS03 PTSDY3. THE
INCLUSION OF POINTS IN THIS PRODUCT WILL EVENTUALLY BE DISCONTINUED.
NOTE: THE NEXT DAY 2 OUTLOOK IS SCHEDULED FOR 1730Z
|