Winter Storm in Michigan, February 11 to 12, 2002

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MARQUETTE MI
445 PM EST MON FEB 11 2002

MAIN CONCERNS ARE WINDS...LES AND HEADLINES.

CURRENT SFC ANALYSIS SHOWS DEEPENING 985MB LOW PRES OVER SW ONTARIO
ASSOCIATED WITH A STRONG VORT MAX OVER THE CANADIAN PRAIRIES. SW
WINDS AHEAD OF THE SYSTEM ARE CURRENTLY GUSTING TO 35-45 KT ACROSS
THE FA WHERE THERE IS A SHALLOW LAYER OF INSTABILITY NEAR THE SFC
WHICH IS HELPING TO MIX THE 50KT 1000FT WINDS TO THE SURFACE. BEHIND
THE LOW...STRONG COLD ADVECTION ALONG WITH A STRONG ISOALOBARIC
COMPONENT LEADING TO GUSTS TO 45-50KT OVER ND. THESE WINDS ARE
EXPECTED TO MOVE INTO THE AREA TONIGHT BEHIND THE COLD FRONT. THERE
MIGHT ACTUALLY BE A BREAK IN WINDS FOR AWHILE THIS EVENING AS
INVERSION STRENGTHENS AHEAD OF THE FRONT IN STRONG WAA...BUT THEY
SHOULD PICK BACK UP QUICKLY IMMEDIATELY BEHIND THE FRONT.

A COUPLE OF ISSUES TO DEAL WITH TONIGHT. OVER THE WEST...LES WILL
PICK UP ON THE BACK SIDE OF THE LOW AS WINDS TURN NW BY MIDNIGHT.
ALTHOUGH H8 TEMPS DO NOT GET TOO OUT OF CONTROL (ONLY -14C BY
MORNING)...STRONG CYCLONIC FLOW WILL LEAD TO RAPID LES DEVELOPMENT.
MAIN PROBLEM FOR THE WEST...HOWEVER WILL BE THE STRONG 30-40KT BL
WINDS WHICH WILL LIMIT THE EFFECTIVE FETCH OVER THE LAKE. WSETA
OUTPUT SHOWS DECENT BANDING DEVELOPING OVER THE WEST AFTER
MIDNIGHT...HOWEVER MAX PCPN IS DISPLACED WELL INLAND...TO THE POINT
OF BEING FURTHER INLAND FROM TYPICAL LES BELTS IN NW FLOW (POSSIBLY
INTO FAR NW IRON CO AND WESTERN BARAGA COUNTY). HAVE THEREFORE OPTED
TO KEEP ALL HEADLINES AS IS OVER THE WEST...HOWEVER WILL GO WITH
WARN FOR BARAGA WITH POTENTIAL SIG LES OVER ALBERTA...WATTON...ETC.
WITH FETCH BEING LIMITED BY STRONG WINDS...NOT TOO OVERLY IMPRESSED
WITH SNOW AMTS...HOWEVER SOME AREAS COULD SEE UP TO 8 INCHES IN 12
HOURS...AND GIVEN THE STRONG WINDS CREATING NEARLY WHITEOUT
CONDITIONS AT TIMES TONIGHT...FELT WARN REMAINS APPROPRIATE. ALSO
NOT SURE HOW MUCH SNOW KEWEENAW WILL SEE TONIGHT WHERE NW FLOW AND
STRONG WINDS WILL CAUSE WORST FETCH OF THE WHOLE WESTERN UP.
HOWEVER...GIVEN THEY WILL ALSO SEE THE STRONGEST WINDS...SEE NO
REASON TO MAKE ANY CHANGES TO THEM EITHER.

OTHER ISSUE TONIGHT WILL BE THE WINDS ACROSS THE AREA. NW FLOW
DEFIANTLY FAVORS NW FA...AS FLOW WILL BE ONSHORE. WILL THEREFORE
KEEP HIGH WINDS IN WSW...WITH NEAR WHITEOUT POSSIBLE. BEST
ISOALOBARIC COMPONENT GENERALLY BTWN 06-12Z...WITH H8 WINDS 50KT OR
SO. OVER THE MQT/BARAGA-ALGER/LUCE WILL KEEP ADV GOING AS
ISOALOBARIC COMPONENT WEAKER WITH A LITTLE MORE FRICTION FROM LAND
OVER MQT/BARAGA. NOT TOO CONVINCED FAR SOUTH WILL SEE ADV WINDS IN
NW FLOW GIVEN STRONG FRICTIONAL DECREASE AS WELL AS BEING FARTHEST
AWAY FROM BEST ISOALOBARIC COMPONENT.

WILL CONTINUE WITH LES TMRW OVER THE FA IN NW FLOW ON TUESDAY. WITH
SECONDARY SHORT WAVE MOVING THROUGH TMRW AFTN...LES SHOULD BE
ENHANCED ESPECIALLY OVER THE EAST WHERE INVERSION IS AROUND 10KFT.
SNOWS MAY START TAPERING OFF LATE OVER THE WEST WHERE DRIER AIR
FILTERS INTO THE REGION BEHIND NEXT SHORT WAVE. HOWEVER...OVER THE
EAST...SIGNIFICANT ACCUMULATIONS COULD OCCUR ON TUESDAY WHERE
DELTA-T VALUES RISE TO +23C BY AFTN WITH STRONG CONVERGENT FLOW AND
LONG FETCH. WILL GO 4 TO 8 INCHES TMRW OVER THE EAST WITH ONLY 2 TO
5 OVER THE WEST.

WILL CONTINUE TO DECREASE WINDS ON TUE AFTN-TUE NIGHT AS LOW PULLS
AWAY. CONCERN WILL BE POTENTIAL FOR BLO ZERO TEMPS TUE NIGHT AWAY
FROM THE LAKE AS RIDGE AXIS BUILDS IN AND WINDS RELAX. PROBABLY NOT
BELOW ZERO NEAR LAKE AS NLY WINDS AND CLDS WILL LIMIT COOLING. LES
SHOULD START TO DECREASE OVER THE EAST...HOWEVER WILL KEEP WARNING
GOING AS WSETA CONTINUES TO SHOW HIGH INVERSION WITH CONTINUED
MOISTURE BLO 700 MB. BY MORNING...DRY AIR SHOULD FILTER INTO THE
EAST ALSO SHUTTING DOWN THE SNOW.

PRETTY QUIET DAY ON WED ON BACK SIDE OF HIGH...WITH TEMPS REBOUNDING
TO NR OR ABV NORMAL TEMPS AGAIN.

ONE EASIER ASPECT TO THE FCST TODAY IS THE EXTENDED...WHERE ALL THE
MODELS ARE IN VERY GOOD AGREEMENT THROUGH DAY 5...WITH THE MRF
ENSEMBLES IN GOOD AGREEMENT WITH EACH OTHER THROUGH DAY 7. BEHIND
THE SYSTEM TODAY...FLOW REMAINS FAIRLY PROGRESSIVE ACROSS THE
NORTHERN TIER OF THE U.S. AS THE POLAR VORTEX STAYS LOCKED UP N OF
HUDSON BAY THROUGH THE PERIOD. SEVERAL SHORT WAVES MOVE THROUGH THE
AREA...ONE ON THU AND ANOTHER FRI NIGHT AND SAT...BUT NONE BRING ANY
SIGNIFICANT COLD AIR TO THE REGION. ONLY QUICK BURSTS OF COLD
AIR...WHICH MAY CAUSE A LITTLE LES...BUT IT DOES NOT LOOK MAJOR AT
THIS TIME. A STRONGER UPPER TROUGH DIGS INTO THE WEST COAST OVER THE
WEEKEND...WITH A SHORT WAVE MOVING OUT OF THE SW INTO THE PLAINS ON
SUNDAY. THIS WILL CAUSE RISING HEIGHTS OVER THE UPR MIDWEST ON
SUNDAY AS THE RIDGE AXIS PASSES TO THE EAST BY MONDAY MORNING. AS
THE SHORT WAVE MOVES NE...H8 TEMPS RISE ABV 0C DURING THE AFTN ON
MONDAY LEADING TO A SNOW CHANGING TO RAIN SCENARIO MONDAY. TEMPS
STILL GENERALLY ABV NORMAL THROUGH THE EXTENDED.

COORD WITH APN AND YQT...THANKS.

.MQT...STORM WARNING LAKE SUPERIOR.
       WINTER STORM WARNING TNT-TUE          MIZ001>003.
       WINTER STORM WARNING LATE TNT-TUE MIZ004
       SNOW/BLOWING SNOW ADVY TNT-TUE MORN   MIZ009.
       HIGH WIND ADVY TNT MIZ004>007-014.
       WINTER STORM WARNING TUE-TUE NIGHT MIZ006>007-014.

MRD