Area Forecast Discussion
Issued by NWS Grand Forks, ND

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50

000
FXUS63 KFGF 182044
AFDFGF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND FORKS ND
344 PM CDT THU SEP 18 2014

.SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT)
ISSUED AT 339 PM CDT THU SEP 18 2014

CHALLENGE FOR THIS FORECAST INCLUDE POPS PLACEMENT WITH ACTIVE
PERIOD SETTING UP FOR THE NEXT 48 HOURS. MODELS HANDLING GENERAL
SYNOPTIC FEATURES WELL WITH THE NORMAL SPREAD IN CONVECTIVE QPFS
GENERATED OVER THE NEXT COUPLE DAYS.

THIS AFTERNOON INTO THE OVERNIGHT PERIOD WILL CONTINUE TO SEE LOW
LEVEL JET BRINGING MOISTURE AND WARMER BLYR TEMPS TO THE AREA.
WITH WAA AND MOISTURE STREAMING INTO THE REGION MIXING WILL
OFFSET SUNDOWN AND ALLOW SFC WINDS TO STAY UP. LATER TONIGHT...
AROUND 9Z...HRRR/RAP/HOP-WRF ENSEMBLE BRING IN SOME CONVECTION
ACROSS THE CENTRAL VALLEY...WILL KEEP THE CHANCE OF SHRA AND
THUNDER.

BY FRIDAY 1.5 INCH PWATS WITH A SFC TROUGH AND WESTERLY WINDS
NOSE INTO THE WESTERN CWFA. THE MOISTURE/INSTABILITY COMBINED
WITH THE SLOW MOVING TROUGH AND ZONAL FLOW WILL ALLOW FOR THE
POTENTIAL FOR ANY WEAK PERTURBATION IN THE FLOW TO INITIATE SHOWER
AND THUNDERSTORMS. BEST CHANCE WILL BE ALONG THE TRACK OF THE SFC
LOW WHERE MODELS AGREEMENT IS DEPICTING IT ACROSS THE NORTHERN
VALLEY INTO NW MN.

.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 339 PM CDT THU SEP 18 2014

THE NEXT SHORT WAVE IS ESCORTED ON THE NOSE OF 300MB JET
SATURDAY. COLD CORE ALOFT WITH -20C ADVECTING IN AT 500MB WILL
BRING AFTERNOON SHOWERS AND THUNDER POTENTIAL...GIVEN THE CURRENT
TIMING BEST CHANCES WILL BE IN NW MN. WIND POTENTIAL IN ITS WAKE
IS A CONCERN ACROSS E ND AND RRV AS 30 TO 35 KTS OF NW WIND MAY
MIX TO NEAR 800MB.

EXTENDED PERIOD BEGINS WITH LONG WAVE RIDGE OVER PACIFIC NORTHWEST
WITH TROUGH OVER GREAT LAKES. NORTHWEST DRY FLOW INDICATED FOR THE
NORTHERN PLAINS AS THE UPPER PATTERN TRANSITIONS TO THE EAST THROUGH
THE MIDDLE OF THE WEEK. THIS WOULD PLACE RIDGE OVER FORECAST AREA
TUE/WED ACCOMPANIED BY ABOVE NORMAL TEMPS BY 5 TO 10 DEGREES. SOME
DISAGREEMENT BETWEEN GFS AND ECMWF ENTERS THE PICTURE BY LATER
WEDNESDAY WITH TROUGHINESS IN THE GFS AND MORE OF A CLOSED LOW FOR
THE ECMWF. EITHER OF THESE SOLUTIONS INTRODUCES LOW POPS TO THE
FORECAST DURING THIS TIME.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1249 PM CDT THU SEP 18 2014

IFR CLD COVER RAPIDLY ERODING WITH VFR CONDITIONS ARRIVING AT VALLEY
AIRFIELDS. GRADIENT WIND FROM SOUTH STARTING TO INCREASE
NOW...EXPECT 15 TO 20 KTS G25 EVERYWHERE BY MID AFTERNOON. RW/TRW TO
APPROACH OVERNIGHT INTO THUR...SUFFICIENTLY LOW POP WARRANTS
OMISSION FROM TAFS AT THIS TIME.


&&

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

$$

SHORT TERM...JK
LONG TERM...WJB/JK
AVIATION...WJB







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