Area Forecast Discussion
Issued by NWS Bismarck, 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 KBIS 042023
AFDBIS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BISMARCK ND
323 PM CDT MON MAY 4 2015

.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 240 PM CDT MON MAY 4 2015

THE MAIN FORECAST PROBLEM IN THE SHORT TERM PERIOD WILL BE FIRE
WEATHER CONCERNS TUESDAY AFTERNOON FOR PORTION OF NORTH CENTRAL
NORTH DAKOTA INTO THE NORTHERN JAMES RIVER VALLEY.

WEAK SURFACE HIGH PRESSURE OVER THE FORECAST AREA THIS AFTERNOON
WILL CONTINUE TO MOVE EAST WITH DEEPENING LOW PRESSURE IN THE
LEE OF THE NORTHERN ROCKIES...IN RESPONSE TO AN APPROACHING UPPER
LEVEL TROUGH THAT MOVES ONTO THE SOUTHERN BRITISH COLUMBIA COAST
TONIGHT.

SHOULD BE A QUIET NIGHT WEATHER WISE ACROSS WESTERN AND CENTRAL
NORTH DAKOTA. THE AFOREMENTIONED DEEPENING LOW PRESSURE WILL KEEP
A GRADIENT WIND THROUGH THE NIGHT...SO EVEN THOUGH WE WILL HAVE
MOSTLY CLEAR SKIES ACROSS THE NORTH...TEMPERATURES SHOULD REMAIN
MAINLY IN THE 40S.

SOUTHERLY WINDS INCREASE ON TUESDAY...BRINGING INCREASING MOISTURE
INTO THE REGION. HOWEVER THE NORTH AND EASTERN PORTIONS OF THE
FORECAST AREA WILL BE THE LAST TO SEE THE INCREASING MOISTURE.
AFTERNOON RELATIVE HUMIDITIES FROM THE BOTTINEAU AND ROLETTE AREAS
SOUTH INTO THE NORTHERN JAMES RIVER VALLEY DROP TO 20 TO 25
PERCENT TUESDAY AFTERNOON...AS WINDS RAMP UP TO 15 TO 20 MPH WITH
GUSTS TO 25 TO 30 MPH. THUS CRITICAL FIRE WEATHER ISSUES WILL BE
POSSIBBLE IF THESE CONDITIONS PAN OUT. THERE IS SOME UNCERTAINTY
AS A SLOWER TIMING WOULD LIKELY RESULT IN LESS WINDS. THUS FOR NOW
WILL ISSUE A FIRE WEATHER WATCH AND LET EVENING/OVERNIGHT SHIFTS
TAKE ANOTHER LOOK AS NEW MODELS ARRIVE.

.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 240 PM CDT MON MAY 4 2015

FOCUS IN THE LONG TERM IS ON THE DEVELOPMENT AND PROGRESSION
OF THE WEST COAST TROUGH THIS WEEK THROUGH THE WEEKEND.

THE 12 UTC RUNS OF THE GFS AND ECMWF ARE IN GOOD AGREEMENT ON
BOTH THE PROGRESSION AND TIMING. AS THE ECMWF SOLUTION HAS COME
MORE INTO LINE WITH THE INITIALLY SLOWER PROGRESSION OF THE GFS IN
RECENT RUNS.

AS THE WEST COAST TROUGH DEEPENS TUESDAY AND WEDNESDAY AN UPPER
LEVEL IMPULSE AHEAD OF THE TROUGH WILL MOVE NORTH NORTHEAST INTO
THE NORTHERN PLAINS...BRINGING WIDESPREAD RAINFALL TO WESTERN AND
CENTRAL NORTH DAKOTA TUESDAY NIGHT INTO AT LEAST THURSDAY
AFTERNOON. THE GFS SOLUTION CONTINUES TO PROGRESS THE IMPULSE A
BIT SLOWER...LINGERING RAINFALL ACROSS CENTRAL AND WESTERN NORTH
DAKOTA INTO EARLY FRIDAY MORNING.

OVER THE WEEKEND THE UPPER LEVEL TROUGH WILL PROPAGATE EAST INTO
THE CENTRAL PLAINS. THE 12 UTC RUNS OF THE GFS AND ECMWF ARE IN
AGREEMENT ON TIMING...HOWEVER THE ECMWF CONTINUES TO KEEP THE
CLOSED 500 MB LOW FURTHER SOUTH AND ONLY BRUSHES CENTRAL NORTH
DAKOTA WITH A SHOT OF RAIN LATE SUNDAY INTO EARLY MONDAY. WHILE
ALSO BEING WETTER THE GFS ALSO IS A BIT COLDER AND SUGGESTS A
POSSIBLE MIX OF RAIN AND SNOW.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 240 PM CDT MON MAY 4 2015

VFR CONDITIONS FOR EACH OF THE TAF SITES WITH INCREASING
SOUTHEASTERLY WINDS LATE IN THE PERIOD.

&&

.BIS WATCHES/WARNINGS/ADVISORIES...
FIRE WEATHER WATCH FROM TUESDAY AFTERNOON THROUGH TUESDAY
EVENING FOR NDZ004-005-012-013-022-023-025-036-037.

&&

$$

SHORT TERM...TWH
LONG TERM...MM
AVIATION...TWH


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