Area Forecast Discussion
Issued by NWS Grand Forks, ND

Home | Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary On
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 042007
AFDFGF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND FORKS ND
307 PM CDT SAT JUL 4 2015

.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 307 PM CDT SAT JUL 4 2015

CONVECTION CHANCES...HOW SEVERE...AND HOW MUCH RAINFALL WILL BE
THE MAIN CHALLENGES FOR THE SHORT TERM.

WV LOOP SHOWS A FAIRLY VIGOROUS LEAD SHORTWAVE MOVING THROUGH THE
EASTERN DAKOTAS...AND THE MAIN SHORTWAVE TROUGH OVER WESTERN
CANADA CURRENTLY. SOUTHERLY WINDS HAVE STARTED TO PICK UP OVER
THE CWA AHEAD OF THE MAIN LOW IN EASTERN MT...AND THE DEVILS LAKE
BASIN HAS FINALLY STARTED TO CLEAR OUT FROM THE SMOKE ALTHOUGH THE
EASTERN CWA IS STILL REPORTING A LOT OF REDUCED VIS. EVEN WITH THE
SMOKE...THERE HAS BEEN ENOUGH HEATING TO ALLOW TEMPS TO GET INTO
THE 80S...AND WITH DEW POINTS IN THE 60S THE MIXED LAYER CAPE IS
ALREADY TOPPING 2000 J/KG IN WESTERN PORTIONS OF THE CWA. STORMS
ARE ALREADY STARTING TO FIRE IN NORTHEASTERN MT NEAR THE CENTER OF
THE SFC LOW AND THE COLD FRONT THAT WILL MOVE THROUGH LATER IN THE
PERIOD. THE EMC WRF HAS THIS ACTIVITY MOVING QUICKLY EASTWARD AND
APPROACHING OUR NORTHERN COUNTIES BY 00 TO 02Z OR SO. FURTHER
SOUTH...THE HRRR IS PERSISTING ON BREAKING OUT SOME PRECIP OVER
THE SOUTH CENTRAL PORTION OF ND IN THE NEXT HOUR OR SO AND MOVING
IT EAST...BUT CU FIELD IS MOSTLY SOUTH OTHER THAN SOME STREETS
STARTING TO SHOW UP OVER THE RED RIVER VALLEY.

THINK AT THIS POINT THAT THE FURTHER SOUTH ACTIVITY WILL BE FAIRLY
ISOLATED AND THAT THE BULK OF THE STORMS WILL BE NEAR THE MAIN LOW
AND COLD FRONT. THE SFC TROUGH AXIS WILL MOVE EASTWARD INTO THE
CWA BY LATE EVENING AND INTO THE OVERNIGHT. CURRENTLY BULK SHEAR
VALUES ARE BELOW 20 KTS...BUT THE NAM AND GFS BOTH SHOW A BRIEF
PERIOD LATER TONIGHT WHERE THEY GET UP TO AROUND 40KTS IN THE
NORTHERN CWA BEFORE THE INSTABILITY STARTS TO DECREASE. WILL
CONTINUE TO INCLUDE A SEVERE MENTION FOR MAINLY THE NORTHERN
VALLEY AND WESTWARD FOR THIS EVENING. SOME OF THE MODELS HAVE A
BRIEF BREAK IN CONVECTION DURING THE EARLY MORNING HOURS AND
OTHERS MAINTAIN SOME PRECIP OVER MAINLY OUR EASTERN COUNTIES INTO
SUNDAY AM. WILL KEEP SOME CHANCE POPS GOING FOR MOSTLY THE
NORTHERN COUNTIES BUT THINK THERE WILL BE SOME SORT OF LULL BEFORE
STORMS REDEVELOP SUNDAY AFTERNOON.

UPPER FLOW INCREASES BY SUNDAY AS THE MAIN TROUGH DIGS INTO
MONTANA...AND THE SFC TROUGH AND COLD FRONT WILL BE ENTERING THE
CWA. THERE ARE STILL SOME MODEL DIFFERENCES IN IF WE WILL GET
SOME STRONG DESTABILIZATION OVER THE SOUTHEASTERN CWA TO COINCIDE
WITH BETTER DEEP LAYER SHEAR BEHIND THE COLD FRONT. STILL...THERE
IS A PERIOD SUNDAY AFTERNOON AND EVENING WHERE THERE WILL BE SOME
VERY UNSTABLE AIR OF OVER 2000 J/KG AND MARGINAL SHEAR OF 30 KTS
ALONG WITH A BOUNDARY NEARBY...SO SOME SEVERE ACTIVITY IS
POSSIBLE. INCLUDED A SEVERE MENTION IN THE SOUTHERN COUNTIES WHERE
THE BEST INSTABILITY WILL BE. THE MODELS SHOW SIGNS OF A WEAK
EMBEDDED SHORTWAVE REINFORCING SOME HIGH QPF VALUES...ALTHOUGH
THEY ARE TRENDING SOUTH OUT OF THE CWA. KEPT SOME FAIRLY HEAVY
RAIN THOUGH FOR THE SOUTHERN COUNTIES...AND WILL REEVALUATE IF WE
GET A ROUND TONIGHT AND ANOTHER ROUND FOR SUNDAY NIGHT SETTING UP
OVER THE SAME AREA.

.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 307 PM CDT SAT JUL 4 2015

MONDAY THROUGH TUESDAY...THE UPPER TROUGH WILL MOVE THROUGH THE
CWA AND OFF TO THE EAST...LEAVING WEST TO NORTHWESTERLY FLOW
ALOFT. THERE COULD BE SOME LINGERING SHOWERS AND STORMS ON MONDAY
BEHIND THE COLD FRONT...BUT THINK IT WILL BE PRETTY ISOLATED SO
KEPT POPS LOW AT THIS POINT. TEMPS WILL BE PRETTY COOL WITH GOOD
COLD AIR ADVECTION. KEPT HIGHS FOR MONDAY IN THE UPPER 60S TO LOW
70S WITH TUESDAY RECOVERING INTO THE 70S.

TUESDAY NIGHT THROUGH SATURDAY...WITH NORTHWEST FLOW CONTINUING
ALOFT AND THE APPROACH OF A WEAK SHORTWAVE EARLY ON WEDNESDAY WE
CAN EXPECT A RETURN TO SOUTHERLY WINDS AT THE SURFACE...WARMER AND
SLIGHTLY MORE HUMID CONDITIONS... AND SCATTERED SHOWERS AND
THUNDERSTORMS FPR WEDNESDAY AFTERNOON AND EVENING. THURSDAY THEN
LOOKS TO BE DRY BUT WARMER STILL AND OVERALL FLOW SHIFTS FROM A
MORE SOUTHERLY DIRECTION. LONGER RANGE MODEL GUIDANCE INDICATES
THAT UPPER LEVEL TROFFING SHOULD INCREASE OFF THE CALIFORNIA COAST
FROM THURSDAY INTO FRIDAY WITH A MORE CONVECTIVELY UNSTABLE
SOUTHERWESTERLY H5 FLOW ARCHING INTO THE CENTRAL AND NORTHERN
PLAINS FROM FRIDAY INTO SATURDAY. LOW LEVEL SOUTHERLY FLOW IS ALSO
EXPECTED TO INCREASE FROM FRIDAY INTO SATURDAY...WITH COMMENSURATE
INCREASE IN MOISTURE AND RISK FOR STRONG THUNDERSTORMS.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 121 PM CDT SAT JUL 4 2015

REDUCED VSBY DUE TO SMOKE FROM DISTANT FIRES WILL PARTIALLY
DISPERSE DUE TO INCREASING SOUTHERLY BLAYER FLOW...WITH VFR
CONDS EXPECTED ACROSS MOST AREAS THROUGHHOUT THE AFTERNOON.
WIDELY SCT THUNDERSTORMS ARE EXPECTED TO DEVELOP INTO
NORTHEASTERN ND FROM LATE AFTERNOON INTO EARLY EVENING. SCT
STRONG TO SEVERE TSTMS AND ARE POSSIBLE ALG THE RRV AND
EASTWARD THROUGH THE EVENING...SPREADING INTO NORTHWEST MN DURING
THE OVERNIGHT PERIOD.


&&

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

$$

SHORT TERM...JR
LONG TERM...JR/GUST
AVIATION...GUST


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