Scientific Forecaster Discussion

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AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND FORKS ND
912 PM CDT WED APR 23 2014

.UPDATE...
ISSUED AT 911 PM CDT WED APR 23 2014

A RAIN SNOW MIX HAS BEEN REPORTED IN EASTERN BECKER, HUBBARD AND 
BELTRAMI COUNTIES WHERE TEMPS FELL BELOW 35 OR 36 DEGREES. MODEL 
SOUNDINGS MARGINALLY SUPPORT SNOW IN THE FAR EASTERN ZONES WITH MOST
OF THE SOUNDING BELOW FREEZING BUT ONLY FOR A FEW HOURS. WILL ADD
A RAIN/SNOW MIX IN THE EASTERN ZONES FOR TONIGHT. ALSO LOWERED
TEMPS IN THE EAST AND KEPT THE SAME OR INCREASED TEMPS ELSEWHERE.

UPDATE ISSUED AT 717 PM CDT WED APR 23 2014

BANDS OF PRECIPITATION CONTINUE TO ROTATE NORTHEAST INTO THE NW-SE 
BAND OVER THE NORTHERN RED RIVER VALLEY. PRECIPITATION WAS MOVING TO 
THE NORTHEAST AT 20 TO 25 KNOTS. WATER VAPOR LOOP INDICATED A SHORT 
WAVE OVER WESTERN/CENTRAL ND. WITH PASSAGE OF SHORT WAVE, SHOULD 
SHUT DOWN THE HEAVIER PRECIP FOR THE EVENING AND EARLY MORNING 
HOURS. NEXT SHORT WAVE EXPECTED FOR THU. 

WINDS WERE STILL UP EARLY THIS EVENING BUT NOT AS STRONG AS THIS 
AFTERNOON. SO WILL LET WIND ADVISORY EXPIRE AT 7 PM CDT. TWEAKED 
WINDS FOR OVERNIGHT. 

&&

.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 300 PM CDT WED APR 23 2014

MOST AREAS WITHIN THE WIND ADVISORY CURRENTLY JUST BELOW ADVISORY
CRITERIA...BUT VERY CLOSE AND WILL LET THIS PRODUCT RIDE UNTIL
00Z. 

THIS IS A COMPLICATED PATTERN...BUT MODELS ARE IN GOOD AGREEMENT
WITH A GENERAL SOLUTION. UPPER LEVEL FLOW WILL BECOME SOUTHWEST
TONIGHT AS THE UPPER LEVEL TROUGH CONTINUES TO APPROACH THE
REGION. THERE ARE MULTIPLE WAVES UPSTREAM THAT WILL AFFECT THE FA
OVER THE NEXT 24-36 HOURS. SHOWERS ARE INCREASING IN AREAL
COVERAGE AS EXPECTED TO THE WEST OF THE 700MB WARM AIR ADVECTION
SHOWERS. THESE SHOWERS TO THE WEST ARE ASSOCIATED WITH 850MB WARM
AIR ADVECTION...AND AN UPPER WAVE THAT CAN BE SEEN ON WATER VAPOR
IMAGERY. THIS ENTIRE AREA OF SHOWERS WILL MOVE THROUGH THE REGION
TONIGHT...ENDING FROM WEST TO EAST. THERE IS ANOTHER WAVE ACROSS
THE SOUTHWEST CONUS THAT THE MODELS ARE BRINGING INTO SOUTHERN MN
BY 18Z THUR...AND THEN MERGING WITH THE UPPER TROUGH CURRENTLY
(20Z) ACROSS MONTANA. THIS SHOULD LEAD TO SHOWERS EAST OF THE
VALLEY ON THURSDAY...GRADUALLY MOVING TO THE EAST (EXACT LOCATION
STILL UNCERTAIN...BUT THE GFS/ECMWF/GEM IN DECENT AGREEMENT). TO
THE WEST OF THIS RAINY AREA...A -30C 500MB COLD POOL WILL
PROPAGATE INTO EASTERN NORTH DAKOTA DURING THE THURSDAY AFTERNOON
HOURS. THIS SHOULD LEAD TO WEAK INSTABILITY...AND WITH ANY HEATING
ANTICIPATE AT LEAST SCATTERED THUNDERSTORMS. THESE STORMS SHOULD
GENERALLY BE WEAK...BUT WITH A SFC AND UPPER LEVEL LOW WITHIN THIS
AREA...THE NON-SUPERCELL TORNADO PARAMETER COULD BE
ELEVATED...LEADING TO THE POTENTIAL FOR A WEAK TORNADO OR TWO
(WHEREVER THE LOW LEVEL WIND SHIFT SETS UP NEAR PEAK HEATING).
INTO THUR NIGHT...THE POTENTIAL EXISTS FOR ACCUMULATING SNOWFALL
AROUND THE BAUDETTE AREA. LATEST MODEL GUIDANCE IS QUICKER
PROPAGATING THE MID-LEVEL LOW EASTWARD...LEADING TO LESS SNOW
POTENTIAL (POSSIBLY UP TO AN INCH).

.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 300 PM CDT WED APR 23 2014

FRIDAY-SATURDAY...LOW LEVEL RIDGING TO BEGIN THE PERIOD
TRANSITIONS TO LOW LEVEL SOUTHERLY FLOW AS THE NEXT SYSTEM SETS UP
ACROSS THE CENTRAL ROCKIES. LOW CHANCES FOR PRECIP EXIST...BUT
MUCH OF THE PERIOD SHOULD BE DRY. TEMPERATURES STILL SOMEWHAT
DEBATABLE DEPENDING ON YOUR MODEL OF CHOICE...BUT CONSENSUS DID
LEAD TO RAISING VALUES A TAD. 

SATURDAY NIGHT-WEDNESDAY...THE POTENTIAL EXISTS FOR A MORE 
ACTIVE PERIOD...BUT DIFFICULT TO PINPOINT THE EXTENT OF PRECIP. MAIN 
SYNOPTIC FEATURES THIS PERIOD WILL BE A STRONG CLOSED LOW MOVING 
ACROSS THE SOUTHERN PLAINS AND A HIGHLY AMPLIFIED RIDGE CENTERED 
ALONG THE WESTERN GREAT LAKES. SEVERE CONVECTION WILL BE THE CONCERN 
ACROSS THE SOUTHERN PLAINS AND LOWER MISSISSIPPI RIVER VALLEY SUNDAY 
THROUGH TUESDAY...BUT PRECIP WILL EXTEND FARTHER NORTH INTO THE 
NORTHERN PLAINS ALONG SFC INVERTED TROUGH AND MID-LEVEL THERMAL 
GRADIENT. PRIMARY QUESTION IS HOW FAR EAST PRECIP WILL PROGRESS 
GIVEN DRY EAST-NORTHEASTERLY LOW-LEVEL FLOW AROUND STRONG HUDSON BAY 
HIGH. OFTENTIMES...THIS DRY AIR CUTS OFF PRECIP OR AT LEAST DELAYS 
ITS ONSET. WILL KEEP WITH ALL BLEND POPS WHICH PLACE HIGHEST CHANCES 
ACROSS SOUTHEAST ND AND LOW CHANCES ACROSS NORTHWEST MN. P-TYPE 
SHOULD BE MOSTLY RAIN...BUT A RAIN/SNOW MIX IS POSSIBLE AT NIGHT. 
TEMPERATURES THROUGH THE PERIOD WILL BE BELOW LATE APRIL NORMALS WITH 
HIGHS IN THE MID 40S TO LOWER 50S AND AND NIGHTTIME LOWS IN THE 
LOWER TO MID 30S. 

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 717 PM CDT WED APR 23 2014

MVFR TO IFR CONDITIONS GENERALLY EXISTS WHERE HEAVIER PRECIPITATION 
WAS FALLING WHICH GENERALLY EXTENDED FROM DVL TO PKD. CIGS WERE 
ABOVE 12 THOUSAND FT OVER FAR NORTHERN MN. EXPECT IFR/MVFR CIGS TO 
SLOWLY SHIFT NORTH AND EAST OVERNIGHT. IFR CONDITIONS MAY REDEVELOP 
OVER EASTERN ND EARLY THU MORNING. 


&&

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

$$

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