Flood Potential Outlook
Issued by NWS Burlington, VT

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11
000
FGUS71 KBTV 051758
ESFBTV
NYC019-031-033-089-VTC001-005-007-009-011-013-015-017-019-021-023-
027-071800-

WINTER/SPRING FLOOD POTENTIAL OUTLOOK
NATIONAL WEATHER SERVICE BURLINGTON VT
1258 PM EST THU MAR 5 2015

...SPRING FLOOD POTENTIAL OUTLOOK /5/...

...LOW PROBABILITY OF SNOW MELT OR ICE JAM FLOODING THROUGH
MID MARCH...

THIS IS THE FIFTH FLOOD OUTLOOK FOR THE 2015 WINTER/SPRING
SEASON. FLOOD OUTLOOKS ARE ISSUED BI-WEEKLY THROUGH THE WINTER AND
SPRING BY THE NATIONAL WEATHER SERVICE IN BURLINGTON VERMONT TO
SUMMARIZE THE FLOOD POTENTIAL DUE TO SNOW MELT AND BREAK UP OF
RIVER ICE ACROSS CENTRAL AND NORTHERN VERMONT, AND NORTHERN NEW
YORK.

...OVERVIEW...

THERE IS A LOW PROBABILITY FOR SNOW MELT OR ICE JAM FLOODING
THROUGH THE MIDDLE OF MARCH. SNOW PACK IS NEAR NORMAL AND RIVER
ICE IS THICK AND EXTENSIVE, HOWEVER NO WARM TEMPERATURES OR
RAINFALL IS FORECAST THAT WOULD PRODUCE EXCESSIVE SNOWMELT AND
ICE JAMS. THE LONGER TERM SPRING MELT AND ICE JAM THREAT IS NEAR
NORMAL.

...SNOW DEPTHS AND WATER EQUIVALENT...

THE SNOW PACK HAS SEEN LIGHT ADDITIONS SINCE LATE FEBRUARY, AND
SNOW DEPTH AND WATER EQUIVALENT IS NEAR NORMAL FOR THIS TIME OF
YEAR.

SNOW DEPTH IN NORTHERN NEW YORK WAS AROUND 18 INCHES IN THE SAINT
LAWRENCE VALLEY, AND TWO TO THREE FEET IN THE ADIRONDACKS. IN THE
HIGHEST TERRAIN MAINLY IN THE HIGH PEAKS REGION SNOW DEPTH WAS
FOUR FEET OR MORE.

IN VERMONT, SNOW DEPTH WAS 18 INCHES TO TWO FEET BELOW 1500 FEET,
AND TWO TO FOUR FEET OVER HIGHER TERRAIN. IN THE HIGHEST PEAKS
SNOW DEPTH WAS FOUR FEET OR MORE.

THE CHAMPLAIN VALLEY OF NEW YORK AND VERMONT HAD SIX INCHES TO A
FOOT OF SNOW COVER.

SNOW WATER EQUIVALENT, OR THE LIQUID WATER CONTENT HELD IN THE
SNOW PACK WAS 1.5 TO 2.5 INCHES IN THE THE SAINT LAWRENCE VALLEY
AND NORTHERN SLOPES OF THE ADIRONDACKS, INCREASING TO FOUR TO SIX
INCHES IN THE HIGH PEAKS. IN VERMONT, INTERIOR VALLEYS HAD THREE
TO FOUR INCHES OF WATER, INCREASING TO SIX TO NINE INCHES OVER
THE HIGHER TERRAIN. THE HIGHEST PEAKS AND MOUNTAIN PASSES HAD 9 TO
12 INCHES OF LIQUID.

SNOW COVER ON THE CHAMPLAIN VALLEY FLOOR HELD AROUND TWO INCHES
OF LIQUID WATER.

...RIVER AND SOIL CONDITIONS...

EXTENSIVE RIVER ICE DEVELOPED IN THE ARCTIC COLD SINCE THE END OF
DECEMBER WITH A SOLID SMOOTH ICE COVER AND ONLY A FEW OPEN LEADS.
THE US GEOLOGICAL SURVEY REPORTED RIVER ICE THICKNESS OF A FOOT TO
A FOOT AND A HALF ON VERMONT AND NORTHERN NEW YORK RIVERS. RIVER
FLOWS FELL TO NEAR NORMAL FOR THE WINTER MONTHS, AND THE LOW
FLOWS AND THICK ICE WILL KEEP THE ICE COVER INTACT.

SOIL MOISTURE WAS NEAR TO ABOVE NORMAL. THE THIN SNOW COVER AND
FRIGID TEMPERATURES HAVE ALLOWED FROST TO PENETRATE DEEP INTO THE
SOIL, WITH FROST DEPTHS DOWN TO 20 INCHES IN AREAS THAT HAD A
LITTLE SNOW COVER THROUGH JANUARY. AREAS THAT HAVE RETAINED SOME
INSULATING SNOW COVER REPORT FROST DEPTHS OF EIGHT TO TEN INCHES.
FROZEN SOILS WOULD ENHANCE RUNOFF RATHER THAN ABSORB EXCESS
MOISTURE.

...WEATHER OUTLOOK...

AFTER THE PROLONGED PERIOD IN JANUARY AND FEBRUARY WHERE THE
NORTHERLY JET STREAM BROUGHT REPEATED OUTBREAKS OF ARCTIC AIR, THE
PATTERN HAS SHIFTED. THE JET STREAM IN EARLY MARCH HAS CHANGED TO
A WESTERLY FLOW TO BRING PACIFIC AIR ACROSS THE CONTINENTAL US.
TEMPERATURES WILL MODERATE THROUGH MID MARCH TO NEAR NORMAL WITH
HIGHS ABOVE FREEZING AND LOWS BELOW FREEZING. PRECIPITATION
OUTLOOKS THROUGH MID MONTH CALL FOR BELOW NORMAL AMOUNTS AS STORM
SYSTEMS ARE CARRIED FURTHER SOUTH OF THE AREA. THIS WEATHER
OUTLOOK IS FAVORABLE FOR NORTHERN NEW YORK AND VERMONT, AS THE
DAILY TEMPERATURE FLUCTUATIONS WILL CREATE CONDITIONS FOR A SLOW
MELT WITH LITTLE RAINFALL ADDING TO RUNOFF.

...SUMMARY...

SNOW MELT OR ICE JAM FLOODING IS NOT FORECAST THROUGH THE MIDDLE
OF MARCH. SNOW COVER CONTINUES TO BE NEAR NORMAL, ALTHOUGH NO
SIGNIFICANT MELT IS EXPECTED AS TEMPERATURES REMAIN SEASONABLY
COOL. RIVER ICE COVERAGE IS WIDESPREAD AND THICK, ALTHOUGH THE ICE
WILL REMAIN LOCKED IN PLACE AS NO SIGNIFICANT RIVER RISES ARE
FORECAST.

THE NEXT WINTER/SPRING FLOOD OUTLOOK WILL BE ISSUED ON THURSDAY
MARCH 19.

ACCESS CURRENT WEATHER CONDITIONS AND FORECASTS ON OUR WEB SITE
AT WWW.ERH.NOAA.GOV/BTV.

$$

HANSON


USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.