Flood in North Dakota, April 1 to 4, 2007

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND FORKS ND
311 PM CDT SUN APR 1 2007

.SHORT TERM...CHALLENGE WILL REVOLVE AROUND WINTER STORM POTENTIAL
MONDAY NIGHT INTO TUESDAY WITH REGARDS TO SNOWFALL AMOUNTS AND
WIND SPEEDS. 12Z MODELS INITIALIZED DECENT AND IN GOOD AGREEMENT
THROUGH ABOUT 30 HRS...THEN DIVERGE. WILL DISCUSS DIFFERENCES
BELOW...BUT WILL STICK WITH THE GFS.

TONIGHT...STACKED SYSTEM WILL CONTINUE TO SLOWLY PROPAGATE NE AND
WEAKEN. DEFORMATION ZONE (PRECIP) WILL ALSO GRADUALLY MOVE NE AND
WEAKEN THROUGH THE NIGHT. EXPECT ALL SNOW BY EVENING ACROSS THE
FAR E FA AS COLUMN COOLS. WE HAVE HAD SOME REPORTS OF
ACCUMULATION...GENERALLY 1-2 INCHES WITH ISOLD REPORTS UP TO 4
INCHES. SFC TEMPS HAVE RISEN ABOVE FREEZING THIS AFTERNOON AND
MOST SNOW IS MELTING UPON CONTACT WITH THE GROUND. AS WE GET INTO
EVENING EXPECT SNOW TO AGAIN ACCUMULATE...UP TO 2 INCHES ACROSS NW
MN SEEMS REASONABLE. MIN TEMPS 25F-30F REASONABLE WITH CLOUD COVER
REMAINING.

MONDAY...BRIEF RIDGING AS FA IS BETWEEN SYSTEMS. UNSURE ABOUT
CLOUD COVER. CURRENT SATELLITE IMAGERY SHOWS SOLID CLOUD COVER
UPSTREAM. RIDGING IS RATHER WEAK...AND NORTHERLY SLOW AT 850MB
DOES NOT BODE WELL FOR CLEARING. THIS NORTHERLY FLOW AT 850MB WILL
ALSO COOL THE AIRMASS. WILL GO MOSTLY CLOUDY...AND NEED TO LOWER
MAX TEMPS A BIT.

MON NIGHT-TUE NIGHT...SHORTWAVE TROUGH WILL EMERGE INTO THE PLAINS
AND STRENGTHEN (CLOSE OFF) IN THE VICINITY OF THE FA. THE NAM CLOSES
THIS SYSTEM OFF ACROSS W ND WHICH IS A LOT SOONER THAN OTHER
GUIDANCE. THIS CAUSES THE NAM TO BE FURTHER NORTH THAN OTHER
GUIDANCE WITH HEAVY BAND OF QPF. 12Z GFS/UKMET/CANADIAN AND 09Z SREF
ALL AGREE WITH HEAVIER BAND OF QPF ACROSS THE SOUTHERN HALF OF THE
FA. NAM ALSO STRONGEST WITH QPF WITH AMTS AROUND 1.0 INCH.
CANADIAN/GFS/SREF ALL INDICATE QPF 0.6-0.8 INCHES IN HEAVIEST BAND
WITH LIGHTER AMTS EITHER SIDE. STRONG FORCING INCLUDING 850MB WARM
AIR ADVECTION AND MID-LEVEL FRONTOGENESIS LEADS TO BANDING
POTENTIAL. STRONG FORCING THROUGHOUT COLUMN MAKES MODEL QPF
REASONABLE. AIRMASS SHOULD BE SUFFICIENTLY COOLED TO SUPPORT ALL
SNOW...AND SATURATION DOES NOT APPEAR TO BE A PROBLEM WITH STRONG
FORCING EXPECTED. CONSIDERING QPF AND LOW RATIO (10:1-13:1)...A
BAND OF 6-10 INCHES OF SNOW APPEARS POSSIBLE. IN ADDITION...WINDS
TUESDAY ON BACKSIDE OF SYSTEM LOOK TO BE NEAR 25MPH (BLOWING SNOW
POSSIBLE). MODELS HAVE BEEN CONSISTENT FOR A FEW RUNS NOW WITH
HEAVY SNOW POTENTIAL...SO WILL GO AHEAD AND ISSUE A WINTER STORM
WATCH FOR MAJORITY OF THE FA (EXCEPT N TIER OF COUNTIES).

WED...SNOW ENDS AS SFC RIDGE BUILDS. AIRMASS REMAINS COOL AND
TEMPS BELOW NORMAL.

.LONG TERM (THU-SUN)... UNSEASONABLY COLD PATTERN FOR LATE IN THE
WEEK AND NEXT WEEK AS UPPER LOW RESIDES OVER GREAT LAKES INTO
WESTERN NEW ENGLAND. THIS WILL ALLOW FOR NORTHERLY 500 MB FLOW AND
FOR COLDER AIR TO SLIDE SOUTHWARD. THE CENTER OF HIGH PRESSURE
WILL RESIDE WEST OF HUDSON BAY WED-FRI BEFORE SHIFTING SOUTHWARD
OVER THE FCST AREA SAT-SUN. DRY WEATHER IS EXPECTED.

&&

.AVIATION...LIGHT SNOW TO GRADUALLY TAPER OFF LATE AFTERNOON AND
EVENING AS UPPER LOW AND WRAPAROUND PCPN SLOWLY MOVES EAST. CIGS
WILL REMAIN IN IFR CATEGORY UNDER THE -SN...BUT RISE INTO THE
LOWER MVFR THRESHOLDS ONCE THE -SN ENDS. UPSTREAM OBS INDICATE
CIGS REMAINING IN THE 1000 TO 2000 FT RANGE THROUGH THE NIGHT.
SOME CHANCE FOR BRIEF CLEARING...ESP FARGO AND SE ND LATE TONIGHT
OR MONDAY MORNING BUT ATTM PLAYED IT CLOUDY. NORTH TO NORTHWEST
WINDS 10 TO 15 KTS WILL PREVAIL.

&&

.FGF WATCHES/WARNINGS/ADVISORIES...
ND...WINTER STORM WATCH FROM LATE MONDAY NIGHT THROUGH TUESDAY
     AFTERNOON FOR NDZ016-027-030.

     WINTER STORM WATCH FROM MONDAY EVENING THROUGH TUESDAY AFTERNOON
     FOR NDZ014-015-024-026-028-029-038-039-049-052>054.

MN...WINTER STORM WATCH FROM LATE MONDAY NIGHT THROUGH TUESDAY
     AFTERNOON FOR MNZ001>003-007>009-013>017-022>024-027-028-
     030>032.

     WINTER STORM WATCH FROM MONDAY EVENING THROUGH TUESDAY AFTERNOON
     FOR MNZ029-040.

&&

TG/RIDDLE

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE GRAND FORKS ND
343 PM CDT SUN APR 1 2007

MNZ001>009-013>017-022>024-027>032-040-NDZ006>008-014>016-024-
026>030-038-039-049-052>054-022045-
WEST POLK-NORMAN-CLAY-KITTSON-ROSEAU-LAKE OF THE WOODS-
WEST MARSHALL-EAST MARSHALL-NORTH BELTRAMI-PENNINGTON-RED LAKE-
EAST POLK-NORTH CLEARWATER-SOUTH BELTRAMI-MAHNOMEN-
SOUTH CLEARWATER-HUBBARD-WEST BECKER-EAST BECKER-WILKIN-
WEST OTTER TAIL-EAST OTTER TAIL-WADENA-GRANT-TOWNER-CAVALIER-
PEMBINA-BENSON-RAMSEY-EASTERN WALSH COUNTY-EDDY-NELSON-
GRAND FORKS-GRIGGS-STEELE-TRAILL-BARNES-CASS-RANSOM-SARGENT-
RICHLAND-WESTERN WALSH COUNTY-
343 PM CDT SUN APR 1 2007

...WINTER STORM WATCH MONDAY NIGHT THROUGH TUESDAY AFTERNOON FOR A
MAJORITY OF THE REGION...

...MONITOR THE LATEST RIVER FORECASTS FOR SPECIFIC FLOOD WARNING
AND WATCH INFORMATION...

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF EASTERN NORTH
DAKOTA...WEST CENTRAL AND NORTHWEST MINNESOTA.

.DAY ONE...THIS AFTERNOON AND TONIGHT

LIGHT SNOW MIXED WITH RAIN AT TIMES WILL GRADUALLY COME TO AN END
TONIGHT. ADDITIONAL SNOW ACCUMULATIONS UP TO 2 INCHES ARE
POSSIBLE ACROSS NORTHWEST MINNESOTA.

.DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY

ANOTHER AREA OF LOW PRESSURE WILL MOVE OUT OF THE NORTHERN ROCKIES
AND BRING THE THREAT OF SNOW TO THE REGION MONDAY NIGHT AND TUESDAY.
SIGNIFICANT ACCUMULATIONS ARE POSSIBLE AND A WINTER STORM WATCH
HAS BEEN ISSUED FOR A MAJORITY OF THE AREA.

.SPOTTER INFORMATION STATEMENT...

SPOTTERS ARE URGED TO CALL INTO THE NATIONAL WEATHER SERVICE WITH
RAINFALL REPORTS AS ACTUAL AMOUNTS ARE EXTREMELY IMPORTANT IN
DETERMINING FUTURE RIVER LEVELS.

TG/VOELKER