Special Weather Statement, NWS Grand Forks, ND

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND FORKS ND
317 PM CDT FRI JUL 19 2013

.SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT)
ISSUED AT 315 PM CDT FRI JUL 19 2013

WATER VAPOR IMAGERY INDICATES A FEW SHORTWAVES UPSTREAM...AND
THUNDERSTORMS HAVE DEVELOPED ALONG A LINE OF SURFACE CONVERGENCE
FROM DEVILS LAKE TO THE NORTHWEST. ANTICIPATE ISOLATED TO SCATTERED
STORM CHANCES WILL CONTINUE TO ADVANCE EAST/SOUTHEAST...WITH
THESE CHANCES GRADUALLY SHIFTING TO THE SOUTHWEST AS THE SECONDARY
COLD FRONT ADVANCES THROUGH THE FA. SEVERE CHANCES WILL BE MINIMAL
CONSIDERING WEAK INSTABILITY (MLCAPE 500-1000 J/KG)...ALTHOUGH
WOULD NOT BE SURPRISED WITH ISOLD HAIL CONSIDERING RELATIVELY LOW
FREEZING LEVELS.

OVERNIGHT LOWS WILL DEPEND ON CLOUD COVER...WHICH MOST LIKELY WILL
BE CLEAR ACROSS THE NORTHERN VALLEY INTO NW MN. HIGH PRESSURE AND
DRY AIRMASS SHOULD LEAD TO MIN TEMPS IN THE LOW TO MID 40S...AND
WARMER TO THE SOUTHWEST.

HIGH PRESSURE WILL LEAD TO MOSTLY DRY WEATHER ON SATURDAY...WITH
MUCH COLDER MAX TEMPS.

MODELS ARE SIGNALING A STRONGER WAVE MAY MOVE ACROSS THE SOUTHERN
FA SATURDAY NIGHT AND LEAD TO SHOWERS AND THUNDERSTORMS. MUCH WILL
DEPEND ON THE ACTUAL TRACK OF THE UPPER WAVE. KEPT THE CHANCE POPS
FOR SOUTHEAST ND INTO WEST CENTRAL MINNESOTA.

.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 315 PM CDT FRI JUL 19 2013

SUNDAY-MONDAY...EXPECTING MUCH OF SUNDAY TO BE DRY AS A STRONG
WAVE APPROACHES FROM THE NORTHWEST. MODELS VARY WITH TIMING AND
STRENGTH OF THIS WAVE. BEST INDICATIONS ARE THAT THE STRONGEST
FORCING WILL BE JUST NORTH OF THE INTERNATIONAL BORDER SUNDAY
NIGHT...WITH STORMS LIKELY NEAR THE INTERNATIONAL BORDER AREA. NOT
SURE ABOUT SEVERE POTENTIAL (IT IS POSSIBLE)...DEPENDENT ON
ACTUAL INSTABILITY AND STRENGTH OF THE LOW LEVEL JET.

MONDAY NIGHT-FRIDAY...LOW AMPLITUDE UPPER LEVEL LONG WAVE TROUGH
OFF THE BC COAST WILL SHIFT A LITTLE SOUTH ALONG THE COAST WHILE A
LONG WAVE UPPER RIDGE WILL BUILD OVER THE NORTHERN ROCKIES THROUGH
THE PERIOD. DOWNSTREAM TROUGH WILL REMAIN OVER THE GREAT LAKES AND
FILL A BIT. THE GFS ENSEMBLE HAS TRENDED STRONGER WITH THE GREAT
LAKES TROUGH AND WEAKER WITH THE BC TROUGH.

THE GFS AND ECMWF WERE SIMILAR AT 84 HOURS. BY DAY 7 THE GFS IS
STRONGER AND SLOWER WITH A TROUGH OVER CENTRAL AND EASTERN CANADA.
WILL PREFER THE ECMWF.

MODELS HAVE BEEN SHIFTING THE PRECIP FARTHER WEST FOR MON NIGHT
THROUGH TUE WITH EACH MODEL RUN. WILL TRIM BACK POPS IN THE FAR
WESTERN ZONES TUE. WILL KEEP POPS PREVIOUS RUNS POPS FOR WED NIGHT
THROUGH FRI AS THE ECMWF IS PREFERRED.

TEMPERATURES HAVE BEEN DECREASED A DEGREE OR TWO FOR TUE AND
INCREASED A DEGREE OR TWO FOR THU AND FRI. HOWEVER HAVE CANCELLED
OUT TEMP INCREASE FOR THU AND FRI.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1254 PM CDT FRI JUL 19 2013

VISIBLE LOOP INDICATED CUMULUS FIELD OVER WEST CENTRAL INTO PARTS OF
NORTHWEST MN. ELSEWHERE CUMULUS WERE DEVELOPING OVER MOST OF THE
REST OF THE AREA. SURFACE DEWPOINTS WERE POOLING ALONG THE
INTERNATIONAL BORDER SOUTH OF ANOTHER COLD FRONT OVER SOUTHERN MAN.
EXPECTED CUMULUS FIELD TO FILL IN THIS AFTERNOON OVER THE NORTHERN
HALF OF THE FORECAST AREA. A BREEZY AFTERNOON IS EXPECTED WITH GUSTS
TO AROUND 25 KNOTS. WINDS WILL BECOME FROM THE NORTH THIS EVENING AS
COLD FRONT MOVES OUT OF CANADA.

&&

.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&

SHORT TERM...TG
LONG TERM...TG/HOPPES
AVIATION...HOPPES

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE GRAND FORKS ND
246 PM CDT FRI JUL 19 2013

MNZ001>009-013>017-022>024-027>032-040-NDZ006>008-014>016-024-
026>030-038-039-049-052>054-201000-
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-EDDY-NELSON-GRAND FORKS-
GRIGGS-STEELE-TRAILL-BARNES-CASS-RANSOM-SARGENT-RICHLAND-
WESTERN WALSH-
246 PM CDT FRI JUL 19 2013

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

.DAY ONE...TODAY AND TONIGHT

SCATTERED THUNDERSTORMS ARE EXPECTED THIS AFTERNOON IN EASTERN NORTH
DAKOTA AND POSSIBLY WEST CENTRAL MINNESOTA...BUT SEVERE WEATHER IS
NOT EXPECTED.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY

THERE IS THE CHANCE FOR STRONG THUNDERSTORMS SUNDAY NIGHT ACROSS
THE DEVILS LAKE BASIN INTO THE NORTHERN RED RIVER VALLEY. THERE
COULD ALSO BE LOCALLY HEAVY RAIN NEAR ANY STORMS SUNDAY NIGHT...AS
MOISTURE STREAMS BACK INTO THE REGION.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT ANTICIPATED.

DK/TG

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS ND
328 PM CDT FRI JUL 19 2013

NDZ006-014-015-192130-
BENSON ND-RAMSEY ND-TOWNER ND-
328 PM CDT FRI JUL 19 2013

...SIGNIFICANT WEATHER ADVISORY FOR SOUTHEASTERN TOWNER...CENTRAL
RAMSEY AND NORTHERN BENSON COUNTIES UNTIL 430 PM CDT...

AT 325 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR WAS TRACKING A
THUNDERSTORM NEAR CANDO...OR 28 MILES NORTHWEST OF DEVILS LAKE...
MOVING TO THE SOUTHEAST AT 25 MPH.

HAIL UP TO THE SIZE OF NICKELS AND WIND GUSTS UP TO 50 MPH ARE
EXPECTED WITH THE STORM.

THE STORM WILL BE NEAR...
STARKWEATHER AROUND 355 PM CDT.
GARSKE AROUND 405 PM CDT.
WEBSTER AROUND 415 PM CDT.
DEVILS LAKE AROUND 430 PM CDT.

BE PREPARED TO TAKE SHELTER IF THE STORMS INTENSIFY AND BECOME
SEVERE...OR A WARNING IS ISSUED BY THE NATIONAL WEATHER SERVICE.

LAT...LON 4835 9844 4803 9878 4842 9939 4857 9923
TIME...MOT...LOC 2028Z 307DEG 21KT 4844 9919

WJB