Flood in New York, March 26 to 27, 2003

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BURLINGTON VT
723 AM EST WED MAR 26 2003

UPDATE TO AFD TO DROP FLOOD WARNING FOR THE GREAT CHAZY RIVER IN
NORTHERN NEW YORK. RIVER GAGES AND LOCAL OFFICIALS HAVE REPORTED
THE ICE JAM HAS BROKEN UP AND THE MINOR FLOODING HAS DECREASING ALONG
THE RIVER. OTHERWISE...REST OF FCST LOOKS GOOD.

FORECAST CONCERNS ARE AMOUNT OF PRECIP/TYPE AND EFFECTS ON LOCAL
RIVERS AND STREAMS.

MINOR FLOODING FROM ICE JAMS CAUSED BY INCREASED RUN OFF FROM
SNOWMELT/RAINFALL CONTINUES ACRS NORTHERN NY. THE GREAT CHAZY
RIVER AT PERRY MILLS THIS MORNING IS APPROACHING FLOOD STAGE AND WL
CONTINUE TO MONITOR. GOOD CALL BY DAY SHIFT TO ISSUE ESF PRODUCT
TO ALERT PUBLIC ABOUT FLOOD POTENTIAL...GIVEN EXPECTED
SNOWMELT/RAINFALL AND ASSOCIATED RUNOFF. WL ISSUE FLOOD
STATEMENT FOR THE POSSIBILITY OF MINOR FLOODING ACRS PARTS OF
NORTHERN NY/VT AND CONTINUE FLOOD WARNING FOR GREAT CHAZY RIVER.

OTHERWISE...BIG PIC SHOWS PLENTY OF MOISTURE MOVING ALONG FRNT
TONIGHT WITH STRONG RRQ OF ULVL JET ACRS OHIO VALLEY INTO THE MID
ATLANTIC STATES. COLDER CLOUD TOPS AND LIGHTNING DATA INDICATES
STRONG CONVECTION WITH FRNT ACRS MISS VALLEY WITH DEVELOPING SFC LOW
PRES. THIS LOW PRES AND ASSOCIATED MOISTURE/DYNAMICS WL PROVIDE CWA
WITH SOME RAIN TODAY. MODELS HAVE INITIALIZED WELL WITH 5H TROF
ACRS CENTRAL PLAINS AND ASSOCIATED JET ENERGY OVER THE OHIO VALLEY.
AT 85H MODELS INITIALIZED SIMILAR WITH THERMAL RIDGE ACRS EASTERN
NEW ENGLAND AND DEVELOPING CAA BEHIND FRNT OVER THE NORTHERN
PLAINS. THEREFORE WL USE MODEL BLEND FOR TEMP FCST THROUGH FIRST
COUPLE OF PERIODS.

SFC ANALYSIS PLACES WEAK FRNT ACRS CENTRAL NEW ENGLAND WITH
SECONDARY COLD FRNT OVER THE GREAT LAKES ATTM. WEAK AREA OF LOW PRES
OVER WESTERN PA IS MOVING TOWARD CWA AND IS ENHANCING RAINFALL
BASED ON RADAR TRENDS. MODELS QPF FIELDS ARE HANDLING PRECIP AREA
VERY WELL ATTM.

TODAY-TONIGHT...MID/UPPER LVL TROF DEVELOPS ACRS NE CONUS AS SHORT
WAVE AND JET ENERGY MOVES THROUGH OUR CWA TODAY. ALSO...LLVL CAA
CONTINUES WITH SFC FRNT PUSHING INTO SNE BY THIS EVENING. MODELS IN
VERY GOOD AGREEMENT WITH MOVING LOW PRES FROM WESTERN PA INTO SNE
TODAY AND THE ASSOCIATED QPF FIELD. FEEL WITH GOOD 850-700MB Q-VECTOR
CONVERGENCES...STRONG 7H FG...AND PLENTY OF ULVL DIVERGENCE WITH RRQ
OF JET...WL MENTION POPS NEAR 100 PERCENT TODAY CENTRAL/EASTERN CWA.
NEXT QUESTION WL PRECIP MIX WITH WET SNOW. GFS/ETA IN GOOD
AGREEMENT WITH PROGGED 85H TEMPS DROPPING BELOW -2C ACRS WESTERN CWA
TODAY...ALONG WITH LLVL THICKNESS VALUES COLD ENOUGH TO SUPPORT.
THEREFORE WL MENTION SOME WET SNOW FLAKES ACRS HIGHER TERRAIN WITH
ACCUMULATIONS OF AN INCH OR LESS. TONIGHT...CYCLONIC UPSLOPE FLOW
CONTINUES AROUND DEPARTING SFC LOW PRES. WS-ETA SHOWS GOOD LLVL LIFT
AND LEFTOVER MOISTURE ACRS HIGHER TERRAIN. WL MENTION SOME MTN
-SW/FLURRIES THIS EVENING. HIGH PRES WL BUILD INTO CWA OVERNIGHT AND
SKIES WL BECOME MOSTLY CLR FROM WEST TO EAST ACRS OUR CWA. WITH
CLRING SKIES AND LIGHT WINDS WL TREND TEMPS TOWARD COOLER MET
GUIDANCE.

THURSDAY-FRIDAY...HIGH PRES MOVES ACRS CWA THURSDAY AND OFF THE
ATLANTIC SEABOARD BY FRIDAY AFTERNOON. WL CONTINUE WITH PREVIOUS
FCSTER THINKING AND KEEP THURSDAY AND FRIDAY DRY WITH TEMPS SLOWLY
WARMING BACK TO ABOVE NORMAL. FRIDAY...SOUTHERLY FLOW AROUND HIGH
PRES WL HELP IN DEVELOPING STRONG LLVL WAA ACRS OUR CWA. PROGGED
925MB TEMPS AND LLVL THICKNESS VALUES SUGGEST AROUND 50F FOR THURSDAY
AND NEAR 60F FOR FRIDAY ACRS THE CHAMPLAIN VALLEY.

SATURDAY-SUNDAY...FULL LATITUDE TROF AND ASSOCIATED COLD FRNT
APPROACH OUR CWA. MODELS AGREE ON TRACKING INITIAL SFC LOW PRES
FROM CENTRAL PLAINS INTO CENTRAL/SOUTHERN CANADA BY 00Z SUNDAY. THIS
WL PUSH VERY WARM AIR INTO OUR CWA SATURDAY WITH TEMPS WELL INTO
THE 60S. THIS MILD AIR COMBINED WITH A STRONG 7H THETA
AXIS...GOOD LLVL MOISTURE...AND STRONG VORT MAX ROUNDING TROF BASE
COULD PROVIDE WESTERN CWA WITH CHC FOR THUNDERSTORMS. OTHERWISE...
PREVIOUS FCST THINKING OF LIKELY POPS LOOKS REASONABLE GIVEN
STRENGTH AND MOVEMENT OF SYSTEM. NO CHANGES EXPECTED TO EXTENDED FCST
ATTM.

.BTV...NONE.

TABER

NYZ026>031-034-035-VTZ001>012-261145-

HAZARDOUS WEATHER OUTLOOK...CORRECTED
NATIONAL WEATHER SERVICE BURLINGTON VT
500 AM EST WED MAR 26 2003

THIS HAZARDOUS WEATHER OUTLOOK IS FOR CENTRAL AND NORTHERN VERMONT
AS WELL AS NORTHERN NEW YORK.

.DAY ONE...TODAY

THE COMBINATION OF WEAK LOW PRESSURE AND A COLD FRONT WILL SPREAD
LIGHT TO MODERATE RAIN ACROSS THE REGION TODAY. PRECIPITATION
AMOUNTS WILL RANGE FROM AROUND A TENTH OF AN INCH ACROSS THE SAINT
LAWRENCE VALLEY TO NEAR A HALF OF AN INCH ACROSS CENTRAL AND
NORTHERN VERMONT.

THIS RAINFALL COMBINED WITH CONTINUED SNOWMELT ACROSS THE HIGHER
ELEVATIONS WILL INCREASE THE WATER LEVELS ON RIVERS AND STREAMS
THROUGH TONIGHT. ALSO...ISOLATED ICE JAMS WILL CONTINUE TO
OCCUR ACROSS NORTHERN NEW YORK AND PARTS OF VERMONT THROUGH THIS
AFTERNOON...AS A RESULT MINOR FLOODING MAY OCCUR.

A RIVER FLOOD WARNING CONTINUES FOR THE GREAT CHAZY RIVER IN
NORTHERN NEW YORK TODAY FOR MINOR ICE JAM FLOODING.

.DAYS TWO THROUGH SEVEN...

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER CALL TO ACTION STATEMENT...

SPOTTERS AND EMERGENCY MANAGERS ARE ENCOURAGED TO REPORT AN ICE JAMS
OR FLOODING TO THE NATIONAL WEATHER SERVICE IN BURLINGTON.
ALSO...RAINFALL REPORTS WILL BE GREATLY APPRECIATED.

TABER