Area Forecast Discussion
Issued by NWS Bismarck, ND

Home | Current Version | Previous Version | Graphics & Text | 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 KBIS 210702
AFDBIS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BISMARCK ND
202 AM CDT MON JUL 21 2014

.UPDATE...
ISSUED AT 114 AM CDT MON JUL 21 2014

THE MAIN FORECAST CHALLENGE TODAY IS SEVERE WEATHER TIMING. THE
LATEST CONVECTION-ALLOWING MODELS CALL FOR EARLY AFTERNOON CONVECTIVE
INITIATION GENERALLY ALONG AND WEST OF U.S. 83. EASTWARD
PROPAGATION OF AN MCS ALONG INTERSTATE 94 IS THE CONSENSUS
SOLUTION...AND IT MATCHES THE STORM PREDICTION CENTER MODERATE
RISK AREA WELL.

UPDATE ISSUED AT 913 PM CDT SUN JUL 20 2014

SOME CONVECTION HAS DEVELOPED OVER FAR NORTHEASTERN MONTANA INTO
SOUTHERN SASKATCHEWAN AFFILIATED WITH THE RIGHT ENTRANCE REGION OF
A JET STREAK. A FEW OF THESE SHOWERS COULD SNEAK OVER INTO FAR NRN
NORTH DAKOTA...BUT THE MAJORITY SHOULD STAY NORTH.
THEREFORE...HAVE TRIMMED POPS A BIT TOWARDS THE SOUTH. AS FOR THE
CHANCES TOWARDS THE SOUTHERN JAMES RIVER VALLEY...SHORT TERM
GUIDANCE STILL SUGGESTS THE POSSIBILITY OF SOME ACTIVITY
DEVELOPING IN THAT REGION SO WILL LEAVE CURRENT POPS ALONE. UPDATE
HAS BEEN SENT.

UPDATE ISSUED AT 608 PM CDT SUN JUL 20 2014

GOING FORECAST APPEARS IN GOOD SHAPE AND WILL CONTINUE TO KEEP
POPS IN OVER THE NORTHWEST THIS EVENING AS CU FIELD HAS STARTED TO
DEVELOP OVER THIS AREA. IF ANYTHING DOES DEVELOP...INDICES
CONTINUE TO SHOW THAT ANY STORM SHOULD REMAIN TAME. MAIN CONCERN
REMAINS ON EXPECTED CONVECTION MONDAY INTO MONDAY NIGHT. UPDATES
HAVE BEEN SENT.

&&

.SHORT TERM...(THIS EVENING THROUGH MONDAY)

ISSUED AT 209 PM CDT SUN JUL 20 2014

FORECAST HIGHLIGHTS IN THE SHORT TERM PERIOD WILL BE THUNDERSTORM
CHANCES TONIGHT INTO MONDAY...WITH SEVERE STORMS EXPECTED MONDAY
AFTERNOON MAINLY ACROSS THE SOUTHERN ONE HALF OF WESTERN AND
CENTRAL NORTH DAKOTA.

CURRENTLY...ZONAL FLOW ALOFT WITH AN UPPER RIDGE TO OUR SOUTH ACROSS
THE SOUTHERN HIGH PLAINS AND AN UPPER TROUGH TO OUR NORTH OVER
CENTRAL CANADA. MID LEVEL WAA CONTRIBUTING TO A VERY WARM
AFTERNOON WITH TEMPERATURES IN THE MID 80S TO MID 90S MANY
LOCATIONS. A WESTERLY MIXING WIND COUPLED WITH DRY AIR ADVECTION
IS HELPING TO REDUCE HUMIDITY WEST INTO CENTRAL. A BIT MORE SULTRY
EAST WHERE DEWPOINTS REMAIN IN THE LOW TO MID 60S. THESE SHOULD
ALSO DECREASE WITH TIME OVER THE NEXT FEW HOURS.

FOR TONIGHT...UPPER LEVEL JET STREAK WILL BE JUST NORTH OF THE
INTERNATIONAL BORDER ALONG WITH SURFACE LOW PRESSURE (DEVELOPING
NOW ACROSS EASTERN MONTANA) OVER NORTHWESTERN INTO NORTH CENTRAL
SOUTH DAKOTA. FORCING ASSOCIATED WITH THE JET COMBINED WITH
THERMAL UPGLIDE NORTH OF THE LOW MAY TRIGGER ELEVATED SHOWERS
AND/OR THUNDERSTORMS THIS EVENING NORTHWEST EXPANDING EAST
OVERNIGHT INTO THE NORTH CENTRAL. ANOTHER AREA OF ELEVATED
CONVECTION POSSIBLE OVERNIGHT FROM MY FAR SOUTH CENTRAL INTO THE
SOUTHERN JAMES RIVER VALLEY.

ONGOING MONDAY MORNING ELEVATED SHOWERS AND THUNDERSTORMS VERY
POSSIBLE. ATTENTION TURNS TO MONDAY AFTERNOON WHERE WE WILL SEE
THE BEST CHANCE FOR SEVERE WEATHER. EARLY TO MID AFTERNOON STORMS
EXPECTED SOUTHWEST INTO THE SOUTH CENTRAL AS A STRONG S/WV CROSSES
WYOMING AND MOVES INTO FAR SOUTH CENTRAL NORTH DAKOTA BY 00Z.
TIMING OF THE S/WV AND THE POSITION OF THE SFC TROUGH ALL SUGGEST
EARLY AFTERNOON...PERHAPS EVEN LATE MORNING...CONVECTIVE
INITIALIZATION/ROBUST STORM DEVELOPMENT. ALL SEVERE WEATHER
PARAMETERS WILL BE IN PLAY GIVEN THE AMOUNT OF MLCAPE AND DEEP
LAYER SHEAR. THE MOST FAVORABLE AREA FOR SEVERE WEATHER WILL BE
ALONG TO SOUTH OF INTERSTATE 94...AND ESPECIALLY INTO THE JAMES
RIVER VALLEY.

.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 209 PM CDT SUN JUL 20 2014

SLIGHT RISK FOR SEVERE WEATHER CONTINUES FOR SOUTHERN NORTH DAKOTA
AT LEAST FOR THE EARLY EVENING HOURS MONDAY AND POSSIBLE THROUGH
MONDAY NIGHT. IF TIMING OF CURRENT MCS CONTINUES THEN THE BULK OF
THE SEVERE WEATHER THREAT SHOULD SHIFT EAST OF WESTERN AND CENTRAL
NORTH DAKOTA BEFORE MIDNIGHT MONDAY. FOR NOW WILL TAKE A SLOWER
APPROACH AND KEEP SOME MENTION OF STRONG AND/OR SEVERE WORDING
MONDAY NIGHT.

FOR TUESDAY THROUGH FRIDAY...AN AMPLIFYING UPPER RIDGE OVER EASTERN
MONTANA AND INTO SASKATCHEWAN SHOULD KEEP CHANCES OF
SHOWERS/THUNDERSTORMS TO A SLIGHT CHC/CHC TUESDAY AND WEDNESDAY
ACROSS THE WEST AND NORTH...WITH DRY AND WARM CONDITIONS
ELSEWHERE. MORE WIDESPREAD SHOWERS AND THUNDERSTORMS ARE FORECAST
WEDNESDAY NIGHT INTO FRIDAY AS SEVERAL SHORTWAVES RIDE UP AND OVER
AND EVENTUALLY FLATTEN THE RIDGE. IN ADDITION...THE APPROACH OF A
STRONGER UPPER LOW ACROSS SOUTHERN CANADA WILL INCREASE LARGE
SCALE ASCENT THURSDAY NIGHT AND FRIDAY FOR A CONTINUED CHANCE OF
SHOWERS AND THUNDERSTORMS.

FOR FRIDAY NIGHT THROUGH SUNDAY...MAIN EMPHASIS WILL BE FOCUSED ON
THE AFOREMENTIONED SOUTHERN CANADIAN UPPER LOW AS IT SLIDES
SOUTHEAST THROUGH SATURDAY NIGHT. THIS WILL PRODUCE ANOTHER ROUND
SHOWERS AND THUNDERSTORMS FRIDAY NIGHT THROUGH SATURDAY NIGHT.
SUNDAY LOOKS TRANQUIL.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 114 AM CDT MON JUL 21 2014

COVERAGE OF ANY ISOLATED THUNDERSTORMS IS EXPECTED TO BE QUITE
LOW TONIGHT...SO IT WAS LEFT OUT OF THE TAFS. WIDESPREAD
THUNDERSTORMS ARE EXPECTED TO DEVELOP ON MONDAY...WITH GREATEST
CHANCES AFTER 21Z.


&&

.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

UPDATE...SCHECK
SHORT TERM...NH
LONG TERM...KS
AVIATION...JPM






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