Red Flag Warning 27, NWS Bismarck, ND

000 
WWUS83 KBIS 132048
RFWBIS

RED FLAG WARNING
NATIONAL WEATHER SERVICE BISMARCK ND
347 PM CDT WED AUG 13 2008

...RED FLAG WARNING THIS AFTERNOON AND EVENING FOR SOUTHWEST
NORTH DAKOTA FOR LOW RELATIVE HUMIDITY AND GUSTY WEST WINDS...

.CRITICAL FIRE WEATHER CONDITIONS WILL CONTINUE THROUGH EARLY
EVENING OVER SOUTHWEST NORTH DAKOTA. RELATIVE HUMIDITY VALUES THIS
AFTERNOON RANGE FROM 14 TO 18 PERCENT...AND THEY MAY FALL FURTHER
TO NEAR 10 PERCENT IN SOME AREAS. GUSTY WEST TO NORTHWEST WINDS
OF 15 TO 25 MPH WILL ALSO CONTINUE...PRODUCING A VERY HIGH TO
EXTREME FIRE DANGER. THE POTENTIAL EXISTS FOR RAPID AND LARGE
WILDFIRE GROWTH GIVEN THE VERY DRY VEGETATION THAT EXISTS IN
SOUTHWEST NORTH DAKOTA.

NDZ017-018-031>033-040-041-043-044-140200-
/O.CON.KBIS.FW.W.0027.000000T0000Z-080814T0200Z/
MCKENZIE-DUNN-GOLDEN VALLEY-BILLINGS-STARK-SLOPE-HETTINGER-BOWMAN-
ADAMS-
347 PM CDT WED AUG 13 2008 /247 PM MDT WED AUG 13 2008/

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 9 PM CDT /8 PM MDT/
THIS EVENING...

A RED FLAG WARNING REMAINS IN EFFECT UNTIL 9 PM CDT /8 PM MDT/
THIS EVENING. 

AFTERNOON AND EARLY EVENING RELATIVE HUMIDITY VALUES OF 10 TO
18 PERCENT ARE COMBINING WITH WEST TO NORTHWEST WINDS OF 15 TO
25 MPH TO PRODUCE CRITICAL FIRE WEATHER CONDITIONS OVER SOUTHWEST
NORTH DAKOTA. THE POTENTIAL EXISTS FOR RAPID AND LARGE WILDFIRE
GROWTH GIVEN THE VERY DRY VEGETATION.

A RED FLAG WARNING MEANS THAT CRITICAL FIRE WEATHER CONDITIONS
ARE OCCURRING. A COMBINATION OF STRONG WINDS...LOW RELATIVE
HUMIDITY...AND WARM TEMPERATURES ARE CREATING EXPLOSIVE FIRE GROWTH
POTENTIAL.

$$

CJS/RSL

000 
WWUS83 KBIS 140156
RFWBIS

RED FLAG WARNING
NATIONAL WEATHER SERVICE BISMARCK ND
856 PM CDT WED AUG 13 2008

...RED FLAG WARNING FOR PORTIONS OF WESTERN AND SOUTHWESTERN NORTH
DAKOTA HAS BEEN ALLOWED TO EXPIRE...

.EVENING RELATIVE HUMIDITIES HAVE RISEN ABOVE THE CRITICAL
CRITERIA...ENDING THE CRITICAL FIRE THREAT. THE RED FLAG WARNING
HAS BEEN ALLOWED TO EXPIRE.

NDZ017-018-031>033-040-041-043-044-140300-
/O.CAN.KBIS.FW.W.0027.000000T0000Z-080814T0200Z/
MCKENZIE-DUNN-GOLDEN VALLEY-BILLINGS-STARK-SLOPE-HETTINGER-BOWMAN-
ADAMS-
856 PM CDT WED AUG 13 2008 /756 PM MDT WED AUG 13 2008/

...RED FLAG WARNING HAS EXPIRED...

THE RED FLAG WARNING IS NO LONGER IN EFFECT.

EVENING RELATIVE HUMIDITIES HAVE RISEN ABOVE THE CRITICAL
CRITERIA...ENDING THE CRITICAL FIRE THREAT. THE RED FLAG WARNING
HAS BEEN ALLOWED TO EXPIRE.

$$
WAA

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BISMARCK ND
1132 AM CDT WED AUG 13 2008

.SHORT TERM...
THE UPPER LOW SPINNING ACROSS SRN SASK IS THE MAIN PLAYER IN THE
FCST THE NEXT 36-48 HRS...BUT WE WILL SPEND TODAY ON ITS DRY SRN
FLANK. THE 06/12Z NAM AND 12Z GFS SOLUTIONS SHOVE THE 850-HPA
THERMAL RIDGE INTO SW/SC ND THIS AFTN WITH TEMPS OF 20-24 C.
SUBSIDENCE ALOFT IS RESULTING IN STRONG DIABATIC HEATING AND AS A
RESULT BOUNDARY LAYER MIXING WILL BE DEEP /TO 700 HPA OR MORE/
OVER THE SW AND SC THIS AFTN. SFC DEWPOINTS ARE ALREADY IN THE
MID 30S F...AND MIXING WILL ONLY SERVE TO LOWER THEM. AS A RESULT
THE MIN RH WILL FALL TO NEAR 10 PERCENT IN THE FAR SW. EVEN AS FAR
EAST AS KBIS...WE WILL HAVE POTENT MIXING THAT WILL MAKE ANY MLCAPE
WEAK. AS A RESULT...WE HAVE REMOVED POPS FOR THE AFTN SOUTH OF
U.S. HIGHWAY 2. NORTH OF THAT LINE...SOME MID LVL CAA WILL KEEP
TEMPS COOLER...AND THAT COMBINED WITH WEAK VERTICAL MOTION ALOFT
MAKES KEEPING A SLGT CHANCE IN THE FCST PRUDENT.

THE BIG ISSUE THIS AFTN WILL LIKELY BE FIRE WEATHER. SINCE WINDS
ARE ALREADY GUSTY AND RH HAS NOWHERE TO GO BUT DOWN...WE WILL BE
ISSUING A RED FLAG WARNING IN THE SOUTHWEST THROUGH 02Z.

&&

.FIRE WEATHER...
WE WILL BE ISSUING A RED FLAG WARNING FOR SOUTHWEST ND FOR THE
AFTERNOON AND EVENING HOURS. THE RH AT SAND CREEK AND PAINTED
CANYON IS ALREADY AT 25 PERCENT OR LESS...AND WITH EXPECTED DRYING
INDUCED BY MIXING DOWN WARMER AIR ALOFT...THESE VALUES HAVE
NOWHERE TO GO BUT DOWN. SOME OF THE DRIEST AREAS WILL PROBABLY
HAVE A MIN RH AT 10 PERCENT THIS AFTERNOON. WINDS WERE AND STILL
ARE A BIT OF A QUESTION MARK...BUT SINCE THE RAWS SITES ARE
ALREADY GUSTING TO 20 MPH WE FEEL THERE WILL BE SUFFICIENT WINDS
TO NECESSITATE RED FLAG CONDITIONS. THE GOOD NEWS IS THAT BY THU
MIN RH WILL BE WAY UP...AND THE WINDS LIGHTER.

&&

.AVIATION...
EXPECT INCREASING MID CLOUDS AND SFC WINDS GUSTING TO 25KTS OVER
NORTHWEST AND NORTH CENTRAL ND THIS AFTERNOON AND EVENING AS LOW
PRESSURE SPINS OVER SOUTHERN SASKATCHEWAN. VFR CONDITIONS ARE
EXPECTED OVER THE WHOLE AREA...HOWEVER...AS DRY LOW LEVELS WILL
MAKE ANYTHING MORE THAN ISOLATED PRECIP HARD TO COME BY.

&&

.PREV DISCUSSION... /ISSUED 405 AM CDT WED AUG 13 2008/

SHORT TERM...TODAY THROUGH FRIDAY NIGHT
MODELS IN GOOD AGREEMENT TODAY WITH POSITION AND MOVEMENT OF UPPER
LEVEL LOW THAT IS CURRENTLY OVER SASKATCHEWAN. THE LOW IS FORECAST
TO MOVE SOUTH ONLY SLIGHTLY TODAY...THEN TONIGHT IT BEGINS ITS TREK
INTO WESTERN NORTH DAKOTA AND EASTERN MONTANA...WITH THE LOW CENTER
POSITIONED NEAR THE BORDERS OF ND/SD/MT BY THURSDAY EVENING. BY
FRIDAY MORNING THE LOW CENTER IS OVER WYOMING AND CONTINUES SOUTH
INTO COLORADO ON FRIDAY NIGHT. THIS LOW WILL BRING CONSIDERABLE
CLOUDINESS AND INSTABILITY WITH SCATTERED SHOWERS AND
THUNDERSHOWERS.

SEE FIRE WEATHER SECTION REGARDING AFTERNOON RELATIVE HUMIDITIES
TODAY.

LONG TERM...SATURDAY THROUGH WEDNESDAY NIGHT...
MEDIUM RANGE MODELS IN GOOD AGREEMENT WITH LARGE SCALE FEATURES AND
WITH USUAL DIFFERENCES IN STRENGTH AND TIMING OF SMALL SCALE DETAILS.
HAVE FOLLOWED ECWMF FOR THE MOST PART WHICH RESULTS IN ONLY MINOR
CHANGES IN THE GRIDS.

SYSTEM NOW SPINNING OVER SASKATCHEWAN DIGS SOUTH AND DEVELOPS INTO
HIGH OVER LOW BLOCK WITH MAIN ENERGY RIDING OVER RIDGE NORTH OF
BORDER AND MAIN LOW OVER SOUTHERN AND CENTRAL PLAINS. DRY WITH
SEASONABLE TEMPERATURES.

&&

.BIS WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING UNTIL 9 PM CDT /8 PM MDT/ THIS EVENING FOR
NDZ017-018-031>033-040-041-043-044.

&&

CJS/JV/HW

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE BISMARCK ND
551 AM CDT WED AUG 13 2008

NDZ001>005-009>013-017>023-025-031>037-040>048-050-051-141100-
DIVIDE-BURKE-RENVILLE-BOTTINEAU-ROLETTE-WILLIAMS-MOUNTRAIL-WARD-
MCHENRY-PIERCE-MCKENZIE-DUNN-MERCER-OLIVER-MCLEAN-SHERIDAN-WELLS-
FOSTER-GOLDEN VALLEY-BILLINGS-STARK-MORTON-BURLEIGH-KIDDER-
STUTSMAN-SLOPE-HETTINGER-GRANT-BOWMAN-ADAMS-SIOUX-EMMONS-LOGAN-
LA MOURE-MCINTOSH-DICKEY-
551 AM CDT WED AUG 13 2008 /451 AM MDT WED AUG 13 2008/

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTH CENTRAL
NORTH DAKOTA...NORTHWEST NORTH DAKOTA...SOUTH CENTRAL NORTH
DAKOTA...SOUTHEAST NORTH DAKOTA AND SOUTHWEST NORTH DAKOTA.

.DAY ONE...TODAY AND TONIGHT

THERE IS A CHANCE OF THUNDERSTORMS THIS AFTERNOON AND TONIGHT.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

THE THREAT OF THUNDERSTORMS CONTINUES ON THURSDAY...AND IN
SOUTHERN NORTH DAKOTA ON FRIDAY.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL NOT BE NEEDED.

JV