Forecast Discussions mentioning any of "HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 01/26/14


AREA FORECAST DISCUSSION
NWS TUCSON AZ
225 PM MST FRI JAN 24 2014 .SYNOPSIS...GUSTY EAST WINDS DIMINISHING THIS EVENING. A FEW SPRINKLES OR LIGHT SHOWERS POSSIBLE TONIGHT INTO SATURDAY MORNING. OTHERWISE...DRY CONDITIONS WITH ABOVE AVERAGE DAYTIME TEMPERATURES OVER THE WEEKEND INTO THE COMING WEEK. && .DISCUSSION...CLOUD COVER COMBINED WITH SOME COLD AIR ADVECTION FROM NEW MEXICO ASSOCIATED WITH STALLED AND DECAYING FRONTAL BOUNDARY HAS GENERALLY TREATED THE HIGH TEMPERATURE FORECAST RIGHT THIS AFTERNOON. LOSING SOME OF THAT EASTERLY TO SOUTHEASTERLY GRADIENT ENHANCEMENT TO THE WINDS THIS AFTERNOON WITH THAT TREND EXPECTED TO CONTINUE THROUGH THE EVENING AS THEY SLOWLY RELAX TO NORMAL DIURNAL TRENDS BY TOMORROW. THAT SNEAKY LITTLE TROPICALLY INFLUENCED IMPULSE ROTATING UP FROM THE SOUTHWEST NOW PUSHING INTO NORTHERN BAJA WITH SOME MOISTURE ENHANCEMENT JUST AHEAD OF IT INTO NORTHERN SONORA AND FAR SOUTHERN ARIZONA. THE .44 PRECIPITABLE WATER FROM THIS MORNING`S SOUNDING WILL PUSH INTO THE .55 RANGE THIS EVENING...MAYBE A TOUCH HIGHER OVERNIGHT. SHORT RANGE MODEL LAYERED MOISTURE FIELDS CONTINUE TO BRIEFLY DEEPEN THE MOISTURE TONIGHT WITH AN EMPHASIS FOR BORDER AREAS. WEAK ECHOES FILLING IN ON THE RADAR AS THIS OCCURS BUT NOTHING REACHING THE GROUND YET. LATEST HRRR 3KM HAS LIGHT SHOWERS APPROACHING THE INTERNATIONAL BORDER AROUND 6-7PM WITH VIRGA AND VERY LIGHT SHOWERS SPREADING AS FAR NORTH AS THE TUCSON AREA AROUND 10-11PM. STILL LOOKING FOR UP TO A COUPLE HUNDREDTHS POSSIBLE (TRACE - .03) IN SOUTHERN AREAS AND MOUNTAINS...WITH A FEW SPRINKLES OR VERY LIGHT SHOWERS ELSEWHERE (LIKE TUCSON). SOME CLEARING SATURDAY FROM THE WEST AND SOUTHWEST...HELPED BY A SECONDARY WEAK IMPULSE IN THE FLOW FROM THE SOUTHWEST WRAPPING A MID LEVEL DRY SLOT INTO THE AREA. NOT MUCH LEFT OF THE COOLER AIR THAT WORKED INTO EASTERN AREAS FROM THE EAST BY SATURDAY AFTERNOON AS TEMPERATURES REBOUND BACK TO SEVERAL DEGREES ABOVE CLIMO FOR MANY AREAS. NO SIGNIFICANT CHANGES UNTIL SOME SIGNS OF A PATTERN CHANGE WITH A BROADER SCALED SPLIT MEAN TROUGH POSITION THROUGH THE CONUS BUCKLING THE BACK SIDE OF THE RIDGE (THE PORTION PROTECTING US) AROUND NEXT WEEKEND TO START FEBRUARY. && .AVIATION...VALID THRU 26/00Z. SCT-BKN120 OVC200...AFT 25/06Z SCT-BKN CLOUDS AT 6-10K FT AGL AND OVC CLOUDS AOA 15K FT AGL...THEN DECREASING CLOUDS FROM WEST TO EAST AND SCT CLOUDS AOA 20K FT AGL AFTER 25/18Z. ELY/SELY SURFACE WIND OF 10-16 KTS AND GUSTS OF 20-25 KTS UNTIL 25/03Z. SURFACE WIND DIMINISHING EARLY THIS EVENING...WITH SURFACE WIND GENERALLY LESS THAN 10 KTS AFT 25/08Z. AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS. && .FIRE WEATHER...GUSTY EAST TO SOUTHEAST WINDS TODAY WILL EASE THIS EVENING WITH LIGHT WINDS EXPECTED SATURDAY. WINDS FROM SUNDAY ONWARD WILL BE DIURNAL IN DIRECTION WITH THE LATE AFTERNOON WESTERLIES BEING A BIT STRONGER THAN THEY HAVE BEEN. A FEW SPRINKLES OR VERY LIGHT SHOWERS ARE POSSIBLE MAINLY SOUTH OF TUCSON TONIGHT AND EARLY SATURDAY...OTHERWISE DRY CONDITIONS WITH ABOVE AVERAGE HIGH TEMPERATURES ARE EXPECTED INTO NEXT WEEK. && .TWC WATCHES/WARNINGS/ADVISORIES...NONE. && $$ VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON MEYER/CERNIGLIA
AREA FORECAST DISCUSSION
NWS TUCSON AZ
915 AM MST FRI JAN 24 2014 .SYNOPSIS...GUSTY EAST WINDS AND COOLER TODAY. A FEW SPRINKLES POSSIBLE TONIGHT INTO SATURDAY MORNING. OTHERWISE...DRY CONDITIONS WITH ABOVE AVERAGE DAYTIME TEMPERATURES NEXT WEEK. && .DISCUSSION...A COUPLE OF THINGS GOING ON THIS MORNING. FIRST IS THE DECAYING AND STALLING FRONTAL BOUNDARY THROUGH EASTERN AREAS THIS MORNING WITH COOLER AIR TRYING TO PUSH IN FROM NEW MEXICO. GUSTY EASTERLY TO SOUTHEASTERLY SURFACE GRADIENT ENHANCEMENT FOR MUCH OF THE AREA. SO FAR THE FORECAST HANDLES THIS PRETTY WELL WITH BREEZY TO LOCALLY WINDY IN SPOTS BUT BELOW ANY ADVISORY LEVELS. TEMPERATURES NOT SHOWING MUCH OF A TREND OUT WEST BUT THE 6-10 DEGREES OF COOLING IN EASTERN AREAS SEEMS GOOD AS LONG AS THINGS DON`T WASH OUT TOO MUCH. TUCSON IN BETWEEN...STILL SEEMS LIKE A DECENT BET TO KNOCK 1-4 DEGREES OFF OF YESTERDAY`S LOWER 70S AT TIA. SECONDLY...WE HAVE A WEAK TROPICALLY INFLUENCED IMPULSE ROTATING UP FROM THE SOUTHWEST AND ACROSS SOUTHERN ARIZONA AND NORTHERN SONORA LATE TODAY INTO SATURDAY MORNING. SHORT RANGE MODEL LAYERED MOISTURE FIELDS CONTINUE TO BRIEFLY DEEPEN THE MOISTURE ESPECIALLY NEAR THE BORDER TONIGHT. LATEST HRRR 3KM HAS LIGHT SHOWERS APPROACHING THE INTERNATIONAL BORDER AROUND 01Z WITH VIRGA AND VERY LIGHT SHOWERS SPREADING AS FAR NORTH AS THE GREEN VALLEY AREA AROUND 03Z. DON`T EXPECT MUCH FURTHER NORTHWARD PROGRESS THAN MAYBE TUCSON AND THE CATALINAS SO WE`LL KEEP THE MENTION OF SPRINKLES AS FAR NORTH AS THE GREATER TUCSON AREA TONIGHT. AFTER MINOR ADJUSTMENTS CURRENT FORECAST HANDLES THESE TRENDS WELL. STILL LOOKING FOR UP TO A COUPLE HUNDREDTHS POSSIBLE (TRACE - .02) IN SOUTHERN AREAS AND MOUNTAINS...WITH A FEW SPRINKLES ELSEWHERE (LIKE TUCSON). I GUESS ANY PRECIP IS WORTH MENTIONING WHEN YOU HAVE BEEN DRY FOR OVER A MONTH DURING YOUR SECONDARY WET SEASON. && .PREV DISCUSSION...THE MAIN WEATHER STORY FOR TODAY WILL BE THE GUSTY EAST TO SOUTHEAST WINDS AS THE SURFACE PRESSURE GRADIENT CONTINUES TO TIGHTEN THIS MORNING. LATEST MODELS SHOWED THIS PRESSURE GRADIENT RELAXING BY SATURDAY FOR LESS WIND. MID AND HIGH LEVEL MOISTURE INCREASING FROM THE SOUTHWEST WILL BRING SOME SPRINKLES OR LIGHT SHOWERS TO SOUTHEAST ARIZONA TONIGHT INTO EARLY SATURDAY. OTHERWISE...A DRY NORTHWESTERLY FLOW ALOFT WILL PROVIDE DRY CONDITIONS SUNDAY INTO NEXT WEEK. AFTER SLIGHTLY COOLER HIGH TEMPERATURES TODAY...DAYTIME READINGS WILL GRADUALLY REBOUND THROUGH NEXT WEEK UNDER THE DRY NORTHWESTERLY FLOW ALOFT. && .AVIATION...SCT-BKN CLOUDS AT 8K-12K FT AGL AND OVC CLOUDS AOA 20K FT AGL THRU 25/12Z...THEN DECREASING CLOUDS FROM WEST TO EAST AND SCT CLOUDS AOA 20K FT AGL AFTER 25/18Z. ELY/SELY SURFACE WIND OF 12-20 KTS AND GUSTS OF 22-30 KTS UNTIL 24/23Z. SURFACE WIND DIMINISHING LATE THIS AFTERNOON AND EARLY EVENING...WITH SURFACE WIND GENERALLY LESS THAN 10 KTS AFT 25/06Z. AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS. && .FIRE WEATHER...GUSTY EAST TO SOUTHEAST WINDS TODAY. SOME WIND PRONE LOCATIONS MAY APPROACH CRITICAL FIRE WEATHER THRESHOLDS...HOWEVER THESE CONDITIONS ARE NOT EXPECTED TO BE WIDESPREAD. AFTER TODAY...NORMAL DIURNAL WIND TRENDS ARE EXPECTED INTO NEXT WEEK. A FEW SPRINKLES OR VERY LIGHT SHOWERS POSSIBLE MAINLY SOUTH OF TUCSON TONIGHT AND EARLY SATURDAY...OTHERWISE GENERALLY DRY CONDITIONS WITH ABOVE AVERAGE TEMPERATURES INTO NEXT WEEK. && .TWC WATCHES/WARNINGS/ADVISORIES...NONE. && $$ VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON MEYER/CERNIGLIA
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
1011 AM MST FRI JAN 24 2014 .UPDATE... && .SHORT TERM...OVERALL...CURRENT FORECASTS ON TRACK. GUSTY WESTERLY WINDS CURRENTLY ALONG FOOTHILLS AND HAVE SPREAD ACROSS MUCH OF THE URBAN CORRIDOR. AT THIS TIME... HIGHEST GUSTS WERE AROUND 30 MPH. 1500M PRESSURE GRADIENT FROM GRAND JUNCTION TO DENVER HAS INCREASED TO 10.36 MB...UP FROM 9.17 MB AT 15Z. WEAK MOUNTAIN TOP INVERSION AND MOUNTAIN WAVE CREATING THE GUSTY WINDS. MODELS SHOW LITTLE CHANGE IN THE PATTERN INTO THE EVENING...SO THE GUSTY WINDS SHOULD CONTINUE. LATEST RAP SPATIAL CROSS SECTION INDICATING CROSS MOUNTAIN FLOW OF AROUND 25 KTS...SO ANY THREAT OF HIGH WINDS IS LOW. RAP AND HRRR SHOW GUST POTENTIAL OF 40-45 KTS ALONG THE FOOTHILLS...SO SOME GUSTS TO AROUND 50 MPH IN WIND PRONE AREAS NOT OUT OF THE QUESTION. THERE IS A SMALL THREAT OF BLOWING SNOW IN OPEN AREAS WITH THE RECENT SNOW FROM YESTERDAY. FOR NOW WILL JUST COVER IN NOWCASTS FOR THE AFTERNOON. SOME MIXING AND INCREASING SURFACE GRADIENT TO PRODUCE GUSTY NORTHWEST WINDS OVER THE FAR NORTHEAST CORNER. THERE MAY BE SOME BLOWING SNOW THERE AS WELL...WITH LITTLE CHANCE FOR BLOWING DUST WITH THE AMOUNT OF SNOW COVER. HIGH TEMPERATURES TO BE TRICKY TODAY...TEMPERATURES ALREADY IN THE 40S ALONG AND NEAR THE FOOTHILLS WITH 30S MOST AREAS ACROSS THE REST OF THE PLAINS. LAGGING BEHIND ARE LOCATIONS IN THE LOW LYING AREAS FROM GREELEY TO FORT MORGAN. WILL MAKE SOME ADJUSTMENTS TO THE HIGH TEMPERATURES BASED ON CURRENT CONDITIONS. .AVIATION...SOUTHWEST TO WEST WINDS STILL EXPECTED TO TRANSITION TO MORE OF A WEST NORTHWEST DIRECTION BY 19Z. POSSIBLE GUSTS TO 20 KTS WITH PERHAPS 30 KTS AT KBJC. LATEST RAP AND HRRR SUGGESTING LIGHTER WINDS BY 20Z AT KDEN AND KAPA WITH WINDS SHIFTING TO THE SOUTHEAST. WITH THE AMOUNT OF MIXING EXPECTED...NOT SURE ABOUT THE SOUTHEASTERLIES OCCURRING EVEN WITH THE SNOW COVER. WILL CONTINUE THE TREND OF THE CURRENT TAFS...AND MONITOR FOR ANY WIND SHIFT TO THE SOUTHEAST. SOME INCREASE IN MID LEVEL CLOUDS DURING THE AFTERNOON...STILL LOOKS LIKE CEILINGS WILL REMAIN ABOVE 12000 FEET AGL. CEILINGS AS LOW AS 6000 FEET AGL LOOKING LESS LIKELY AT THIS POINT. DRAINAGE TO DEVELOP BY 02Z. && .PREV DISCUSSION... /ISSUED 429 AM MST FRI JAN 24 2014/ SHORT TERM...WARM ADVECTION IS UNDERWAY WITH READINGS RISING INTO THE 30S ACROSS THE FRONT RANGE FOOTHILLS AND NEARBY PLAINS WHERE DOWNSLOPE WINDS HAVE KICKED IN. THERE IS A MEAN STATE CRITICAL LAYER IN PLACE...WHICH WILL LEAD TO A CONTINUATION OF GUSTY MOUNTAIN WAVE WINDS IN AND RIGHT NEXT TO THE FOOTHILLS THROUGH MUCH OF THE DAY. CROSS MOUNTAIN COMPONENT IS ONLY ABOUT 25-30 KTS SO DONT SEE ANY HIGH WIND THREAT AT THIS TIME...BUT HAVE BOOSTED WIND FORECAST A LITTLE MORE. THE GUSTY WINDS AND DRY POWDERY SNOW FROM YESTERDAY COULD LEAD TO AREAS OF BLOWING SNOW THIS MORNING...MAINLY IN OPEN AREAS ALONG HIGHWAY 93 AND POINTS CLOSER TO THE WYOMING BORDER. HIGH TEMPERATURES WILL BE TRICKY TODAY DUE TO SNOW COVER...SHALLOW STRONG INVERSIONS...AND AN INCREASE IN MID/HIGH CLOUDS. AT THIS TIME... EXPECT MOST AREAS TO SCOUR OUT WITH INCREASING WINDS DURING THE DAY...BUT WILL CONTINUE A CONSERVATIVE HIGH TEMPERATURE FORECAST IN LOW LYING AREAS. THIS WOULD INCLUDE THE GREELEY-FORT MORGAN CORRIDOR AND THEN DOWN INTO LINCOLN COUNTY WHERE NOT SURE IF INVERSIONS WILL BREAK WITH SNOW COVER. ALSO EXPECT A DECENT WARM ADVECTION MID LEVEL CLOUD DECK SPILLING SOUTHEAST ACROSS THE EASTERN PLAINS TODAY. MAY EVEN SEE A LITTLE VIRGA CONSIDERING UPSTREAM OBSERVATIONS IN EASTERN MONTANA AND NORTHEAST WYOMING. FOR TONIGHT...SKIES ARE EXPECTED TO GRADUALLY CLEAR AND A RELAXING PRESSURE GRADIENT WILL ALLOW ANY GUSTY WINDS TO DECREASE IN THE EVENING. LONG TERM...WARM AND DRY CONDITIONS WILL PERSIST THROUGH SATURDAY AS WARM AIR UNDER THE LARGE WESTERN U.S. RIDGE REMAINS OVER THE STATE. SUNDAY WILL ALSO BE WARMER THAN CLIMATOLOGY...BUT NOT QUITE AS WARM AS SATURDAY. HEIGHTS AND THICKNESS VALUES WILL BE DROPPING THROUGH THE DAY SUNDAY AS THE UPPER RIDGE BEGINS YIELDING TO AN ARCTIC INTRUSION DROPPING OUT OF CANADA. SUNDAY NIGHT WILL BE TRANSITIONAL AS THE COLD FRONT ARRIVES SOMETIME AROUND MIDNIGHT AND COLD AIR BEGINS POURING INTO THE STATE. ALOFT...STRONG CYCLONIC NORTHWESTERLY FLOW WILL BE IN PLACE TO PROVIDE ADDITIONAL FRONTOGENESIS AT MID AND UPPER LEVELS. THE STRENGTHENING COLD FRONT AND UPSLOPE FLOW SHOULD COMBINE TO PRODUCE A LARGE BAND OF SNOWFALL THAT WILL EVENTUALLY SPREAD FROM THE MOUNTAINS OUT ACROSS THE PLAINS. THEN THE BIG STORY ON MONDAY IS GOING TO BE THE VERY COLD TEMPERATURES. HIGH TEMPERATURES WILL EITHER BE IN THE UPPER TEENS OR LOWER 20S AS THE SNOWFALL CONTINUES. TUESDAY WILL BE ANOTHER COLD DAY AS THE ARCTIC AIR REMAINS OVER THE REGION. LIGHT SNOWFALL MAY ALSO CONTINUE INTO TUESDAY AS THE CYCLONIC NORTHWEST FLOW REMAINS OVER COLORADO. THE UPPER LEVEL JET WILL STILL BE OVER THE STATE...BUT MAY BE WEAKENING THROUGH THE DAY...ALLOWING THE BANDED NATURE OF THE SNOW TO BEGIN BREAKING DOWN. EACH OF THE MEDIUM RANGE MODELS ARE IN PRETTY FAIR AGREEMENT WITH THE SOLUTION THROUGH TUESDAY. LESS AGREEMENT EXISTS FOR LATER IN THE WEEK. HOWEVER...IT DOES SEEM THAT THE UPPER RIDGE IS GOING TO BE UNDERCUT BY SOME ZONAL FLOW OFF THE EASTERN PACIFIC. THIS SHOULD BRING SOME ADDITIONAL MOISTURE OVER THE MOUNTAINS TO KEEP SOME LIGHT SNOW PRODUCTION GOING WEST OF THE CONTINENTAL DIVIDE. PLAINS LOCATIONS SHOULD SEE A RETURN TO DRIER WEATHER WITH MODERATION IN THE TEMPERATURES. TUESDAY SHOULD BE THE LAST DAY WITH TEMPERATURES REMAINING BELOW FREEZING. TEMPERATURES FOR THE LATTER HALF OF THE WEEK SHOULD BE AROUND CLIMATOLOGY...IF NOT A LITTLE WARMER. AVIATION...VFR CONDITIONS WILL PERSIST THROUGH TONIGHT. ENHANCED DRAINAGE WINDS UP TO 20 KTS EARLY THIS MORNING SHOULD GRADUALLY TRANSITION MORE WEST/NORTHWEST AT KDEN AND KAPA BY 18Z-20Z. KBJC COULD SEE GUSTS TO AROUND 30 KTS. MAINLY SCATTERED TO BROKEN CLOUD DECK ABOVE 12000 FEET EXPECTED...ALTHOUGH MID LEVEL CEILINGS AS LOW AS 6000 FT AGL COULD OCCUR JUST EAST OF KDEN FROM 17Z-03Z. && .BOU WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...D-L LONG TERM....DANKERS AVIATION...D-L
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1157 PM CST FRI JAN 24 2014 .DISCUSSION... 258 PM CST SYNOPSIS...WINTER REALLY LOVES THE MIDWEST THIS YEAR. SNOW IS EXPECTED TODAY AND SUNDAY WITH BITTER COLD EXPECTED EARLY NEXT WEEK. FOR HEADLINES... EXTENDED THE CURRENT WINTER WEATHER ADVISORY THROUGH 15Z/9AM CST SATURDAY MORNING DUE TO LINGERING SNOW AND CONTINUED BLOWING/DRIFTING SNOW. WILL NOT ISSUE ANY OTHER HEADLINES WITH THIS PACKAGE. ANOTHER WINTER WEATHER ADVISORY WILL BE NEEDED FOR LATE SATURDAY NIGHT THROUGH SUNDAY NIGHT. THIS ADVISORY...LIKE THE CURRENT ONE...WILL BE FOR SNOW...BLOWING/DRIFTING SNOW...AND BITTERLY COLD TEMPS. IN ADDITION...A WIND CHILL ADVISORY OR WARNING WILL BE NEEDED FOR LATE SUNDAY NIGHT THROUGH TUESDAY NIGHT. RIGHT NOW MONDAY NIGHT LOOKS LIKE THE COLDEST NIGHT WITH MIN WIND CHILLS LESS THAN -30F. REST OF TODAY THROUGH MID SATURDAY MORNING... AN UPPER LEVEL LOW IS OVER HUDSON BAY WITH ITS AXIS STRETCHING FROM NORTHERN LAKE MI THROUGH ST. LOUIS. AT THE SURFACE...LOW PRESSURE IS ALSO OVER HUDSON BAY WHILE HIGH PRESSURE IS SPRAWLED OUT OVER THE GULF COAST. THE TROUGH AXIS/WARM FRONT WILL SWING THROUGH THIS AFTERNOON BRINGING SLIGHTLY WARMER TEMPS AND MORE MOIST AIR. HAVE A FEW ECHOES ON RADAR...BUT GIVEN HOW DRY THE LOW LEVELS ARE AND LACK OF SURFACE OBS REPORTING SNOW WILL CONTINUE TO HAVE SCATTERED FLURRIES IN THE FORECAST THROUGH THIS AFTERNOON. THE MAIN SNOW FOR TODAY/TONIGHT IS CURRENTLY OVER NW WI AND WILL SPREAD OVER NORTHERN IL THIS EVENING. SHORT TERM GUIDANCE HAS REMAINED VERY CONSISTENT WITH TIMING SO LEFT THE ADJUSTMENTS I MADE THIS MORNING AS IS. STEADY SNOW SHOULD BE FALLING ACROSS THE CWA BY 02Z/8PM CST. FORCING WILL BE FROM THE NEXT TROUGH AXIS/COLD FRONT..AND IT EXTENDS UP THROUGH 300MB THROUGH THE EVENING. THE MOIST LAYER IN THE DGZ IS 4500-5000 FT DEEP THIS EVENING SO A STEADY SNOW IS EXPECTED THROUGH MIDNIGHT. THE SNOW WILL COME TO AN END BY MID MORNING AS THE COLD FRONT MAKES IT THROUGH THE WHOLE CWA. ALL IN ALL LOOKING AT 1 TO 3 INCHES. SOME LOCATIONS...ESPECIALLY OVER NW INDIANA...MAY SEE UP TO 4 INCHES. SNOW ENDS FROM NW TO SE EARLY SATURDAY MORNING...BUT GUSTY WINDS AND BLOWING SNOW WILL CONTINUE SO EXTENDED THE WINTER WEATHER ADVISORY THROUGH 15Z. THE MAIN HAZARD WILL BE THE STRONG WINDS AND RESULTANT BLOWING/DRIFTING SNOW. GUSTS UP TO 30KT THIS EVENING AND OVERNIGHT WILL CREATE VERY LOW VISIBILITIES AND WHITE OUT CONDITIONS. WE HAVE ALREADY HEARD OF ROADS CLOSED OR SHUT DOWN TO ONE LANE ACROSS THE CWA. PLEASE TAKE CAUTION ESPECIALLY AFTER THE SUN GOES DOWN THIS EVENING IF YOU ARE TRAVELING! SATURDAY AFTERNOON THROUGH SUNDAY NIGHT... NORTHWEST FLOW ALOFT SETS UP SATURDAY WITH A WEAK SURFACE RIDGE QUICKLY PASSING THROUGH THE REGION. THE NEXT CLIPPER SYSTEM BRINGS SNOW TO THE REGION AFTER MIDNIGHT SATURDAY NIGHT. THE LOW PASSES DIRECTLY OVER NORTHERN IL SUNDAY BEFORE CONTINUING OFF TO THE NORTHEAST. THE MAJORITY OF SNOW WILL FALL BETWEEN MIDNIGHT AND NOON ON SUNDAY...WITH MOISTURE AND FORCING TAPERING OFF AFTER NOON. KEPT SLIGHT CHANCE TO CHANCE POPS A BIT LONGER THAN PREVIOUSLY THOUGHT AS GUIDANCE HINTS AT A SECONDARY BAND OF SNOW AHEAD OF THE UPPER LEVEL TROUGH AXIS. THE GFS IS MUCH MORE EXCITED ABOUT THIS SCENARIO THAN THE ECMWF WHICH IS WHY POPS ARE CAPPED IN THE LOW END CHANCE RANGE. GIVEN THIS IS A CLIPPER SYSTEM...WENT WITH A SLIGHTLY HIGHER/POWDERY SNOW RATIO. LOOKING AT IN GENERAL 3-5 INCHES ACROSS THE CWA. THERE LOOKS TO BE A BREAK IN THE GUSTY WINDS SATURDAY NIGHT...BUT HAVE NO FEAR THEY RETURN SUNDAY AND SUNDAY NIGHT. MAX GUSTS AROUND 30KT ARE EXPECTED WHICH WILL RESULT IN ANOTHER ROUND OF BLOWING AND DRIFTING SNOW. FOR TEMPS...THE FIRST TASTE OF COLD AIR ARRIVES SATURDAY BEHIND THE COLD FRONT. EXPECTING TEMPS TO FALL THROUGH THE DAY WITH LOWS SATURDAY NIGHT VARYING FROM -5 TO +5F ACROSS THE CWA. THE GUSTY WINDS WILL LEAD TO MIN WIND CHILLS BETWEEN -20F AND 0F. THE LOWS WEAK WARM FRONT MAKES IT INTO THE SOUTHERN PARTS OF THE CWA...BUT IN GENERAL SUNDAY LOOKS WARMER. MAY EVEN SEE TEMPS A COUPLE OF DEGREES ABOVE FREEZING ACROSS CENTRAL IL. HOWEVER THE HAMMER FALLS BEHIND THE COLD FRONT AS 925MB TEMPS FALL FROM 0C TO -20C. AS SUCH OVERNIGHT LOWS ARE EXPECTED TO BE -1 TO -10F WITH MIN WIND CHILLS OF -20F TO -35F. A WIND CHILL HEADLINE WILL BE NEEDED. MONDAY THROUGH TUESDAY NIGHT... COLD. BITTERLY COLD. 925MB TEMPS REMAIN BELOW -20C THROUGH TUESDAY NIGHT AS THE TROUGH CONTINUES TO ROTATE OVERHEAD. AT THE SURFACE HIGH PRESSURE BUILDS DOWN THE PLAINS AND PASSES SOUTH OF THE CWA MID WEEK. HIGH TEMPS MONDAY AND TUESDAY WILL BE BETWEEN +1F AND -10F. MONDAY NIGHT LOOKS LIKE THE COLDEST WITH MIN WIND CHILLS BETWEEN -30F AND -45F. ONCE AGAIN WIND CHILL HEADLINES WILL BE NEEDED. EXTENDED...WEDNESDAY AND THURSDAY... THE UPPER LEVEL TROUGH FINALLY SHIFTS EAST WEDNESDAY WITH ANOTHER LOW PASSING TO OUR NORTH THURSDAY. THE ECMWF IS MORE EXCITED ABOUT PRECIP ALONG THE LOWS COLD FRONT THURSDAY THAN THE GFS...SO KEPT POPS IN THE SLIGHT CHANCE TO CHANCE RANGE. OTHERWISE THE EXTENDED LOOKS WARMER WITH TEMPS IN THE SINGLE DIGITS WEDNESDAY AND IN THE 20S THURSDAY. JEE && .CLIMATE... DAILY TEMPERATURE RECORDS: CHICAGO ROCKFORD JAN 27... RECORD LOW MIN TEMP -10 -13 RECORD LOW MAX TEMP -1 -2 JAN 28... RECORD LOW MIN TEMP -13 -22 RECORD LOW MAX TEMP -3 -5 JAN 29... RECORD LOW MIN TEMP -16 -20 RECORD LOW MAX TEMP -6 -9 DEUBELBEISS && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 06Z... * SNOW BECOMING MORE SNOW SHOWERS AND ENDING PRIOR TO DAYBREAK...WITH TEMPORARY IFR VISIBILITY. * WINDS SHIFT TO THE NORTHWEST PRIOR TO DAYBREAK WITH GUSTS AROUND 30 KT THROUGH AT LEAST MIDDAY. * SOME BLOWING AND DRIFTING SNOW WITH SOME MVFR VSBY POSSIBLE INTO THIS MORNING. //DISCUSSION...UPDATED 06Z... LOW PRESSURE ACROSS THE FAR NORTHERN GREAT LAKES WILL SWING A STRONG COLD FRONT ACROSS THE AREA PRIOR TO DAYBREAK WHICH WILL TURN WINDS TO THE NORTHWEST. ALONG THE FRONT AND POSSIBLY FOR AN HOUR OR TWO BEHIND IT WILL EXIST SOME SNOW SHOWERS...WHICH STILL MAY BRING TEMPORARY IFR VISIBILITY. GUSTS SHOULD RE-INCREASE TO AROUND 30 KT AND PERSIST THROUGH THE MORNING AND INTO THE AFTERNOON THANKS TO STRONG COLD AIR ADVECTION. THIS CERTAINLY WILL LEAD TO BLOWING SNOW IN OPEN AREAS...BUT WHETHER THAT IS EXPERIENCED AT EACH AIRFIELD WILL DEPEND ON LOCAL CHARACTERISTICS. QUITE A BIT OF DRY AIR WILL ARRIVE WITH THIS SURGE...SO CLOUDS ARE EXPECTED TO BE NIL TO SCATTERED AT MOST. GOING FORWARD INTO TONIGHT...WINDS WILL BEGIN TO BACK TO THE SOUTH AND EVENTUALLY REACH THAT DIRECTION BY SUNDAY MORNING. SPEEDS WILL COME DOWN TONIGHT...BUT THEN RE-INCREASE QUICKLY ON SUNDAY MORNING. THIS WILL BE ASSOCIATED WITH A WARM FRONT WHICH WILL BRING SNOW TO TAF SITES. THIS LOOKS TO BEGIN OVERNIGHT TO AROUND DAYBREAK SUNDAY FOR CHICAGO AREA TAF SITES. THERE IS POTENTIAL FOR A 3-5 HOUR WINDOW OR SO OF FAIRLY GOOD SNOWFALL RATES /ONE INCH PER HOUR PLUS/ DURING SUNDAY MORNING. //ORD AND MDW CONFIDENCE...UPDATED 06Z... * MEDIUM IN SNOW END TIME AND VISIBILITY DURING SNOW THROUGH DAYBREAK. * MEDIUM IN TIMING OF CIG IMPROVEMENT. * HIGH IN WIND DIRECTION AND SPEED. * WHILE CONFIDENCE IS HIGH IN SOME BLOWING AND DRIFTING SNOW...CONFIDENCE IS LOW ON HOW IT WILL IMPACT VISIBILITY. //OUTLOOK FOR ORD/MDW FOR 12Z SUNDAY-12Z FRIDAY...UPDATED 00Z... SUNDAY...SNOW LIKELY. GUSTY WEST-NORTHWEST WINDS LIKELY RESULTING IN BLOWING AND DRIFTING. IFR/MVFR LIKELY. MONDAY...VFR...EXCEPT GUSTY WEST-NORTHWEST WINDS WITH BLOWING SNOW AND RESULTING MVFR VSBY POSSIBLE. TUESDAY AND WEDNESDAY...VFR. THURSDAY...SLIGHT CHANCE LIGHT SNOW. MVFR POSSIBLE. MTF/RATZER && .MARINE... 404 PM CST A VERY STRONG WIND FIELD PERSISTS THIS AFTERNOON ACROSS THE ENTIRE LAKE...WITH A TIGHT PRESSURE GRADIENT IN PLACE BETWEEN HIGH PRESSURE ACROSS THE SOUTHERN PORTION OF THE COUNTRY AND STRONG LOW PRESSURE TO THE NORTH. ALTHOUGH THE STORM FORCE WINDS ARE ON A DOWNWARD TREND ACROSS THE SOUTHERN HALF...WOULD EXPECT THESE HIGHER WINDS TO CONTINUE THROUGH EARLY EVENING. THEN AS A TROUGH OF LOW PRESSURE AND COLD FRONT MOVE ACROSS THE LAKE...SOUTHWEST WINDS WILL TURN TO THE WEST AND NORTHWEST OVERNIGHT WHILE GALES CONTINUE ACROSS THE ENTIRE LAKE. ALTHOUGH THERE MIGHT BE A DIMINISHING TREND WITH A LULL IN THE GALE ACTIVITY FOR A TIME TONIGHT FOR THE NEARSHORE...ANTICIPATE IT ONLY TO BE A BRIEF PERIOD BEFORE GALES PICK UP ONCE AGAIN. GALES WILL CONTINUE FOR THE ENTIRE LAKE ON SATURDAY WITH WINDS DIMINISHING FIRST ACROSS THE NEARSHORE IN THE AFTERNOON...THEN WINDS DIMINISHING SATURDAY EVENING ACROSS THE OPEN WATERS. WINDS WILL FURTHER DIMINISH LATE SATURDAY NIGHT INTO SUNDAY MORNING...BUT WITH WINDS TO THEN INCREASE ONCE AGAIN SUNDAY EVENING INTO MONDAY AS ANOTHER QUICK MOVING SYSTEM MOVES ACROSS THE REGION. RODRIGUEZ && .LOT WATCHES/WARNINGS/ADVISORIES... IL...WINTER WEATHER ADVISORY...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008- ILZ010-ILZ011-ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-ILZ021- ILZ022-ILZ023-ILZ032-ILZ033-ILZ039 UNTIL 9 AM SATURDAY. IN...WINTER WEATHER ADVISORY...INZ001-INZ002-INZ010-INZ011-INZ019 UNTIL 9 AM SATURDAY. LM...GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565- LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868- LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 9 PM SATURDAY. HEAVY FREEZING SPRAY WARNING...LMZ080-LMZ261-LMZ362-LMZ364- LMZ366-LMZ563-LMZ565-LMZ567-LMZ669-LMZ671-LMZ673-LMZ675- LMZ777-LMZ779-LMZ868-LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 9 PM SATURDAY. GALE WARNING...NEARSHORE WATERS UNTIL 4 PM SATURDAY. HEAVY FREEZING SPRAY WARNING...LMZ740-LMZ741-LMZ742-LMZ743- NEARSHORE GARY TO MICHIGAN CITY IN UNTIL 4 PM SATURDAY. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion National Weather Service Lincoln IL 1116 PM CST Fri Jan 24 2014 .DISCUSSION... ISSUED 840 PM CST Fri Jan 24 2014 Snow continues to slowly increase in coverage over parts of northwest into west central Illinois this evening as a frontal boundary...currently over central Iowa...shifts east into our area late tonight. The snow reports out to our northwest were increasing with vsbys as low as 1 1/2sm in northeast and east central Iowa. Some of the high res model sounding data indicate enough warm air advecting northeast into far southwest Illinois overnight where we may see a wintry mix of precip including rain/freezing rain and snow. But still enough spread in the ensemble members in this area to hold off making any significant changes to the grids with respect to precip type overnight, but that will have to be watched. Quick look at the 00z NAM-WRF showing a trend closer to what the current GFS model suggests with the better threat for accumulating snows over the northeast half of the forecast area...roughly around 1 inch with some isolated 2 inch reports possible east of I-57. Gradient remains tight across central Illinois so even though the snow accumulations will be minor, any snowfall with the gusty winds will produce areas of blowing snow creating slippery travel conditions overnight. WRF ensembles suggest a quick exit to the snow...roughly in the 07z-10z time frame...which the current HRRR is latching on to. For now, will hold on to the current idea of ending the snow from northwest to southeast Saturday morning with actually a lull in the precip chances thru the remainder of the day Saturday before another clipper starts to affect our area after midnight Sat night/Sun morning. We have seen our overnight lows reached early this evening as the persistent south to southwest low level flow will keep temps steady or slowly rising overnight as the trof/wind shift line out to our west tracks thru our area in the morning. Readings over far west central Illinois may hover around 35 for several hours this evening into the early morning hours before the boundary shifts thru the area towards dawn. Other than the usual tweaking of hourly temperatures in the grids for this evening, the current ZFP has a good handle on the weather trends this evening, so will not be needing an update at this time. && .AVIATION... ISSUED 1110 PM CST Fri Jan 24 2014 Snow has overspread much of the area this evening and should continue through about 10z before pushing off to our east. MVFR cigs with local IFR cigs were common in areas that have seen a steadier snowfall. Upstream obs suggest mainly MVFR conditions prevailing with tempo IFR in some of the heavier bursts of snow. Once the snow ends towards dawn on Saturday, latest short term models suggest a return to VFR conditons for the remainder of Saturday. As the surface trof/wind shift moves across the area from northwest to southeast in the 08z-11z time frame, models suggest there may be a period of MVFR-IFR cigs for a time before the trof shifts away from the area. Surface winds ahead of the trof will be southwest at 15 to 25 kts...with occasional gusts near 30 kts...then winds will turn into the northwest as the trof moves off to our east late tonight into the predawn hours of Saturday. Gusty winds out of the northwest are expected during the day on Saturday with prevailing winds of 15 to 25 kts common over the TAF sites, with occasional gusts up to 35 kts possible during the afternoon with winds quickly diminishing after 00z. Smith && .PREV DISCUSSION... ISSUED 221 PM CST Fri Jan 24 2014 Plenty of winter-weather challenges with this forecast package...including chances for accumulating snow tonight and again Saturday night, followed by bitterly cold conditions early next week. SHORT TERM...Tonight through Tuesday Strong southerly winds have developed across central Illinois this afternoon in response to a tightening gradient between high pressure centered over the Gulf Coast and an approaching cold front dropping into the Dakotas. Winds will remain strong and gusty this evening, with forecast soundings and numeric guidance suggesting continued gusts to between 30 and 35mph. Thanks to the steady southerly flow and increasing cloud cover, low temperatures for tonight will be achieved early this evening followed by rising temps overnight. As low pressure tracks eastward across Hudson Bay, a trailing cold front will sweep into the area tonight. Models are in agreement that a period of light snow will accompany the front, although with only weak upper support and limited moisture, accumulations will remain light. Most locations will pick up 1 inch of snow or less tonight, with locations north of the I-74 corridor perhaps measuring as much as 1 to 2 inches. Aside from the falling snow, strong winds will continue through the night causing considerable blowing snow and reduced visibilities. While the light precipitation will be quick to exit toward dawn, brisk northwesterly winds gusting over 30 mph behind the departing front will persist into Saturday. As a result, have opted to extend the Winter Weather Advisory until 9 AM Saturday. Depending on how much snow falls overnight and how much blowing/drifting occurs, the advisory may even need to be extended further into Saturday. After a brief lull during the day Saturday, the next clipper system will quickly approach from the northwest by Saturday night. Model trends have slowed this system just a bit, so have removed POPs during the evening. Models are still not in perfect agreement regarding the exact track of the upper wave, with the GFS remaining further south than the NAM. Consensus tracks the 500mb vort max along/near the I-80 corridor, which would generally keep the heaviest snow just north of the KILX CWA late Saturday night into Sunday morning. Given strong upper dynamics and track across north-central Illinois, have increased POPs with this system. Will carry categorical POPs along/north of I-74 tapering down to just low chance along/south of I-70. Accumulations will once again be on the light side across much of central Illinois, with most areas seeing 1 inch or less. Further north, higher totals of 2 to 3 inches will be possible along/north of I-74 depending upon the exact track of the clipper. Once this system exits the region, mild/dry weather will be the rule Sunday afternoon ahead of an Arctic cold front approaching from the north. Sunday will be the warmest day of the forecast period, with high temperatures reaching the upper 30s and lower 40s. Lift along cold front will be strong enough to support snow flurries or perhaps a few snow-showers Sunday evening, followed by windy and sharply colder conditions overnight. As has been advertised for several days, a considerable chunk of polar air will settle southward across much of the eastern CONUS early next week, resulting in some of the coldest readings thus far this winter. Numeric guidance is suggesting high temperatures on Monday remaining in the single digits and lows Monday night plunging to as low as the teens below zero in many areas. These extremely cold temperatures combined with brisk northwesterly winds will create wind-chill values of 25 below to 35 below zero at times from late Sunday night through Tuesday. Wind chill advisories and/or warnings will be needed as the time nears. LONG TERM...Wednesday through Friday Aside from a generally dry frontal passage on Thursday, the extended will be characterized by dry weather with a gradual warming trend. After sub-zero temperatures early Wednesday morning, an increasingly zonal upper flow pattern will allow temps to warm into the upper 20s and lower 30s by Friday. && .ILX WATCHES/WARNINGS/ADVISORIES... WINTER WEATHER ADVISORY until 9 AM CST Saturday FOR ILZ027>031- 036>038-041>046-048-053>057-063. && $$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
915 PM CST FRI JAN 24 2014 .DISCUSSION... 258 PM CST SYNOPSIS...WINTER REALLY LOVES THE MIDWEST THIS YEAR. SNOW IS EXPECTED TODAY AND SUNDAY WITH BITTER COLD EXPECTED EARLY NEXT WEEK. FOR HEADLINES... EXTENDED THE CURRENT WINTER WEATHER ADVISORY THROUGH 15Z/9AM CST SATURDAY MORNING DUE TO LINGERING SNOW AND CONTINUED BLOWING/DRIFTING SNOW. WILL NOT ISSUE ANY OTHER HEADLINES WITH THIS PACKAGE. ANOTHER WINTER WEATHER ADVISORY WILL BE NEEDED FOR LATE SATURDAY NIGHT THROUGH SUNDAY NIGHT. THIS ADVISORY...LIKE THE CURRENT ONE...WILL BE FOR SNOW...BLOWING/DRIFTING SNOW...AND BITTERLY COLD TEMPS. IN ADDITION...A WIND CHILL ADVISORY OR WARNING WILL BE NEEDED FOR LATE SUNDAY NIGHT THROUGH TUESDAY NIGHT. RIGHT NOW MONDAY NIGHT LOOKS LIKE THE COLDEST NIGHT WITH MIN WIND CHILLS LESS THAN -30F. REST OF TODAY THROUGH MID SATURDAY MORNING... AN UPPER LEVEL LOW IS OVER HUDSON BAY WITH ITS AXIS STRETCHING FROM NORTHERN LAKE MI THROUGH ST. LOUIS. AT THE SURFACE...LOW PRESSURE IS ALSO OVER HUDSON BAY WHILE HIGH PRESSURE IS SPRAWLED OUT OVER THE GULF COAST. THE TROUGH AXIS/WARM FRONT WILL SWING THROUGH THIS AFTERNOON BRINGING SLIGHTLY WARMER TEMPS AND MORE MOIST AIR. HAVE A FEW ECHOES ON RADAR...BUT GIVEN HOW DRY THE LOW LEVELS ARE AND LACK OF SURFACE OBS REPORTING SNOW WILL CONTINUE TO HAVE SCATTERED FLURRIES IN THE FORECAST THROUGH THIS AFTERNOON. THE MAIN SNOW FOR TODAY/TONIGHT IS CURRENTLY OVER NW WI AND WILL SPREAD OVER NORTHERN IL THIS EVENING. SHORT TERM GUIDANCE HAS REMAINED VERY CONSISTENT WITH TIMING SO LEFT THE ADJUSTMENTS I MADE THIS MORNING AS IS. STEADY SNOW SHOULD BE FALLING ACROSS THE CWA BY 02Z/8PM CST. FORCING WILL BE FROM THE NEXT TROUGH AXIS/COLD FRONT..AND IT EXTENDS UP THROUGH 300MB THROUGH THE EVENING. THE MOIST LAYER IN THE DGZ IS 4500-5000 FT DEEP THIS EVENING SO A STEADY SNOW IS EXPECTED THROUGH MIDNIGHT. THE SNOW WILL COME TO AN END BY MID MORNING AS THE COLD FRONT MAKES IT THROUGH THE WHOLE CWA. ALL IN ALL LOOKING AT 1 TO 3 INCHES. SOME LOCATIONS...ESPECIALLY OVER NW INDIANA...MAY SEE UP TO 4 INCHES. SNOW ENDS FROM NW TO SE EARLY SATURDAY MORNING...BUT GUSTY WINDS AND BLOWING SNOW WILL CONTINUE SO EXTENDED THE WINTER WEATHER ADVISORY THROUGH 15Z. THE MAIN HAZARD WILL BE THE STRONG WINDS AND RESULTANT BLOWING/DRIFTING SNOW. GUSTS UP TO 30KT THIS EVENING AND OVERNIGHT WILL CREATE VERY LOW VISIBILITIES AND WHITE OUT CONDITIONS. WE HAVE ALREADY HEARD OF ROADS CLOSED OR SHUT DOWN TO ONE LANE ACROSS THE CWA. PLEASE TAKE CAUTION ESPECIALLY AFTER THE SUN GOES DOWN THIS EVENING IF YOU ARE TRAVELING! SATURDAY AFTERNOON THROUGH SUNDAY NIGHT... NORTHWEST FLOW ALOFT SETS UP SATURDAY WITH A WEAK SURFACE RIDGE QUICKLY PASSING THROUGH THE REGION. THE NEXT CLIPPER SYSTEM BRINGS SNOW TO THE REGION AFTER MIDNIGHT SATURDAY NIGHT. THE LOW PASSES DIRECTLY OVER NORTHERN IL SUNDAY BEFORE CONTINUING OFF TO THE NORTHEAST. THE MAJORITY OF SNOW WILL FALL BETWEEN MIDNIGHT AND NOON ON SUNDAY...WITH MOISTURE AND FORCING TAPERING OFF AFTER NOON. KEPT SLIGHT CHANCE TO CHANCE POPS A BIT LONGER THAN PREVIOUSLY THOUGHT AS GUIDANCE HINTS AT A SECONDARY BAND OF SNOW AHEAD OF THE UPPER LEVEL TROUGH AXIS. THE GFS IS MUCH MORE EXCITED ABOUT THIS SCENARIO THAN THE ECMWF WHICH IS WHY POPS ARE CAPPED IN THE LOW END CHANCE RANGE. GIVEN THIS IS A CLIPPER SYSTEM...WENT WITH A SLIGHTLY HIGHER/POWDERY SNOW RATIO. LOOKING AT IN GENERAL 3-5 INCHES ACROSS THE CWA. THERE LOOKS TO BE A BREAK IN THE GUSTY WINDS SATURDAY NIGHT...BUT HAVE NO FEAR THEY RETURN SUNDAY AND SUNDAY NIGHT. MAX GUSTS AROUND 30KT ARE EXPECTED WHICH WILL RESULT IN ANOTHER ROUND OF BLOWING AND DRIFTING SNOW. FOR TEMPS...THE FIRST TASTE OF COLD AIR ARRIVES SATURDAY BEHIND THE COLD FRONT. EXPECTING TEMPS TO FALL THROUGH THE DAY WITH LOWS SATURDAY NIGHT VARYING FROM -5 TO +5F ACROSS THE CWA. THE GUSTY WINDS WILL LEAD TO MIN WIND CHILLS BETWEEN -20F AND 0F. THE LOWS WEAK WARM FRONT MAKES IT INTO THE SOUTHERN PARTS OF THE CWA...BUT IN GENERAL SUNDAY LOOKS WARMER. MAY EVEN SEE TEMPS A COUPLE OF DEGREES ABOVE FREEZING ACROSS CENTRAL IL. HOWEVER THE HAMMER FALLS BEHIND THE COLD FRONT AS 925MB TEMPS FALL FROM 0C TO -20C. AS SUCH OVERNIGHT LOWS ARE EXPECTED TO BE -1 TO -10F WITH MIN WIND CHILLS OF -20F TO -35F. A WIND CHILL HEADLINE WILL BE NEEDED. MONDAY THROUGH TUESDAY NIGHT... COLD. BITTERLY COLD. 925MB TEMPS REMAIN BELOW -20C THROUGH TUESDAY NIGHT AS THE TROUGH CONTINUES TO ROTATE OVERHEAD. AT THE SURFACE HIGH PRESSURE BUILDS DOWN THE PLAINS AND PASSES SOUTH OF THE CWA MID WEEK. HIGH TEMPS MONDAY AND TUESDAY WILL BE BETWEEN +1F AND -10F. MONDAY NIGHT LOOKS LIKE THE COLDEST WITH MIN WIND CHILLS BETWEEN -30F AND -45F. ONCE AGAIN WIND CHILL HEADLINES WILL BE NEEDED. EXTENDED...WEDNESDAY AND THURSDAY... THE UPPER LEVEL TROUGH FINALLY SHIFTS EAST WEDNESDAY WITH ANOTHER LOW PASSING TO OUR NORTH THURSDAY. THE ECMWF IS MORE EXCITED ABOUT PRECIP ALONG THE LOWS COLD FRONT THURSDAY THAN THE GFS...SO KEPT POPS IN THE SLIGHT CHANCE TO CHANCE RANGE. OTHERWISE THE EXTENDED LOOKS WARMER WITH TEMPS IN THE SINGLE DIGITS WEDNESDAY AND IN THE 20S THURSDAY. JEE && .CLIMATE... DAILY TEMPERATURE RECORDS: CHICAGO ROCKFORD JAN 27... RECORD LOW MIN TEMP -10 -13 RECORD LOW MAX TEMP -1 -2 JAN 28... RECORD LOW MIN TEMP -13 -22 RECORD LOW MAX TEMP -3 -5 JAN 29... RECORD LOW MIN TEMP -16 -20 RECORD LOW MAX TEMP -6 -9 DEUBELBEISS && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 03Z... * GUSTY SOUTHWEST WINDS 25-30 KT EASING SLIGHTLY THROUGH LATE EVE. WIND SHIFTS NORTHWEST EARLY SAT MORNING AND GUSTS AROUND 30 KT AGAIN. * PERIODS OF LIGHT SNOW OVERNIGHT...WITH VISIBILITY SOMEWHAT VARIABLE BETWEEN 1-2SM AT TIMES TO BETTER THAN 6SM AT OTHERS. PERIOD OF MORE SOLID IFR VSBYS POSSIBLE 05-08Z. SNOW ENDS BY SATURDAY MORNING. MVFR CIGS TO SCATTER TO VFR SATURDAY MORNING. * GUSTY WEST-NORTHWEST WINDS TO 30 KT SATURDAY. MAY MAINTAIN BLOWING AND DRIFTING SNOW WITH SOME MVFR VSBY IMPACT ESPECIALLY EARLY. RATZER //DISCUSSION...UPDATED 00Z... WINDS... DEEPENING LOW PRESSURE OVER HUDSON BAY AND STRONG HIGH PRESSURE ALONG THE GULF COAST HAVE COMBINED TO TIGHTEN THE SURFACE PRESSURE GRADIENT ACROSS THE MIDWEST TODAY...PRODUCING GUSTY SOUTHWEST WINDS ACROSS THE TERMINALS WHICH WILL ONLY SLOWLY DECREASE OVERNIGHT. CURRENT OBS CONTINUE TO SHOW GUSTS NEAR 30 KT AT ORD/MDW WHILE EASING A BIT TO THE WEST AT RFD. DESPITE GRADUAL DECREASE EXPECT GUSTS TO REMAIN GENERALLY 25+ KT FOR MUCH OF THE NIGHT AS WINDS SLOWLY VEER FROM 210-220 DEG TO 250-260 DEG AFTER MIDNIGHT AHEAD OF AN APPROACHING COLD FRONT. COLD FROPA 07-09Z AT RFD AND 08-10Z IN CHICAGO WILL PRODUCE A WIND SHIFT TO THE NORTHWEST 300-320 DEG...BUT WITH WINDS COMING BACK UP 25-30 KTS BEHIND THE FRONT INTO SATURDAY. VERY GRADUAL DECREASE THEN EXPECTED IN SPEEDS/GUSTS AGAIN SATURDAY AFTERNOON. SNOW...AND VIS/CIG IMPLICATIONS... STRONG GUSTY SOUTHWEST WINDS AHEAD OF COLD FRONT AND POTENT MID- LEVEL DISTURBANCE CONTINUE TO ADVECT FAIRLY DRY LOW LEVEL AIR FROM THE PLAINS INTO THIS STORM SYSTEM...AS NOTED IN THE OMA 12Z RAOB FROM THIS MORNING WHICH WAS BONE DRY BELOW ABOUT 600 MB. DESPITE STRONG DYNAMICS/ASCENT...MOST OF THE LIFT IS GOING INTO LONG PROCESS OF SATURATION AND CLOUD/PRECIP DEVELOPMENT. WHILE SOME PATCHY LIGHT SNOW/FLURRIES WERE DEVELOPING ACROSS PARTS OF THE AREA...IT APPEARS THE BEST CHANCE FOR MORE ORGANIZED WIDESPREAD SNOW WILL COME LATER THIS EVENING WITH STRONGER MID-LEVEL VORT DIGGING SOUTH- SOUTHEAST FROM MINNESOTA EARLY THIS EVENING. THEREFORE WITH SLOWER SATURATION OCCURRING...HAVE INDICATED SOME A GRADUAL MINOR VSBY REDUCTION THROUGH ABOUT 04Z IN TAFS WITH THE 04-10Z PERIOD EXPECTED TO BE MORE LIKELY TO SEE IFR VSBYS AND ACCUMULATING SNOW. FORECAST SOUNDINGS THE STRONGEST LIFT IS ABOVE THE BETTER SNOW GROWTH THERMAL RANGE...AND SOME DRYING BEGINS AT THE TOP OF THIS LAYER BY 10Z OR SO...WITH SNOW EXPECTED TO TAPER OFF BEYOND THAT TIME. OF COURSE GUSTY WINDS WILL WORSEN BLOWING/DRIFTING AND VSBY ISSUES WITH NEW FALLING SNOW. SOME BLOWING SNOW MAY LINGER SATURDAY MORNING AFTER SNOW ACTUALLY STOPS FALLING...THOUGH DIFFICULT TO ASSES IMPACT TO VISIBILITY WITH MUCH DETAIL AT THIS TIME ESPECIALLY IN URBAN CHICAGO TERMINALS. RATZER //ORD AND MDW CONFIDENCE...UPDATED 03Z... * HIGH CONFIDENCE IN WIND TRENDS. * MEDIUM-HIGH CONFIDENCE IN SNOW TIMING AND VSBY/INTENSITY TRENDS OVERNIGHT. * HIGH CONFIDENCE IN CIGS IMPROVING TO VFR SATURDAY...MEDIUM CONFIDENCE IN VSBY WITH SOME LINGERING BLOWING SNOW ESPECIALLY IN THE MORNING. RATZER //OUTLOOK FOR ORD/MDW FOR 12Z SUNDAY-12Z FRIDAY...UPDATED 00Z... SUNDAY...SNOW LIKELY. GUSTY WEST-NORTHWEST WINDS LIKELY RESULTING IN BLOWING AND DRIFTING. IFR/MVFR LIKELY. MONDAY...VFR...EXCEPT GUSTY WEST-NORTHWEST WINDS WITH BLOWING SNOW AND RESULTING MVFR VSBY POSSIBLE. TUESDAY AND WEDNESDAY...VFR. THURSDAY...SLIGHT CHANCE LIGHT SNOW. MVFR POSSIBLE. RATZER && .MARINE... 404 PM CST A VERY STRONG WIND FIELD PERSISTS THIS AFTERNOON ACROSS THE ENTIRE LAKE...WITH A TIGHT PRESSURE GRADIENT IN PLACE BETWEEN HIGH PRESSURE ACROSS THE SOUTHERN PORTION OF THE COUNTRY AND STRONG LOW PRESSURE TO THE NORTH. ALTHOUGH THE STORM FORCE WINDS ARE ON A DOWNWARD TREND ACROSS THE SOUTHERN HALF...WOULD EXPECT THESE HIGHER WINDS TO CONTINUE THROUGH EARLY EVENING. THEN AS A TROUGH OF LOW PRESSURE AND COLD FRONT MOVE ACROSS THE LAKE...SOUTHWEST WINDS WILL TURN TO THE WEST AND NORTHWEST OVERNIGHT WHILE GALES CONTINUE ACROSS THE ENTIRE LAKE. ALTHOUGH THERE MIGHT BE A DIMINISHING TREND WITH A LULL IN THE GALE ACTIVITY FOR A TIME TONIGHT FOR THE NEARSHORE...ANTICIPATE IT ONLY TO BE A BRIEF PERIOD BEFORE GALES PICK UP ONCE AGAIN. GALES WILL CONTINUE FOR THE ENTIRE LAKE ON SATURDAY WITH WINDS DIMINISHING FIRST ACROSS THE NEARSHORE IN THE AFTERNOON...THEN WINDS DIMINISHING SATURDAY EVENING ACROSS THE OPEN WATERS. WINDS WILL FURTHER DIMINISH LATE SATURDAY NIGHT INTO SUNDAY MORNING...BUT WITH WINDS TO THEN INCREASE ONCE AGAIN SUNDAY EVENING INTO MONDAY AS ANOTHER QUICK MOVING SYSTEM MOVES ACROSS THE REGION. RODRIGUEZ && .LOT WATCHES/WARNINGS/ADVISORIES... IL...WINTER WEATHER ADVISORY...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008- ILZ010-ILZ011-ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-ILZ021- ILZ022-ILZ023-ILZ032-ILZ033-ILZ039 UNTIL 9 AM SATURDAY. IN...WINTER WEATHER ADVISORY...INZ001-INZ002-INZ010-INZ011-INZ019 UNTIL 9 AM SATURDAY. LM...GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565- LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868- LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 9 PM SATURDAY. HEAVY FREEZING SPRAY WARNING...LMZ080-LMZ261-LMZ362-LMZ364- LMZ366-LMZ563-LMZ565-LMZ567-LMZ669-LMZ671-LMZ673-LMZ675- LMZ777-LMZ779-LMZ868-LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 9 PM SATURDAY. GALE WARNING...NEARSHORE WATERS UNTIL 4 PM SATURDAY. HEAVY FREEZING SPRAY WARNING...LMZ740-LMZ741-LMZ742-LMZ743- NEARSHORE GARY TO MICHIGAN CITY IN UNTIL 4 PM SATURDAY. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion National Weather Service Lincoln IL 849 PM CST Fri Jan 24 2014 .DISCUSSION... ISSUED 840 PM CST Fri Jan 24 2014 Snow continues to slowly increase in coverage over parts of northwest into west central Illinois this evening as a frontal boundary...currently over central Iowa...shifts east into our area late tonight. The snow reports out to our northwest were increasing with vsbys as low as 1 1/2sm in northeast and east central Iowa. Some of the high res model sounding data indicate enough warm air advecting northeast into far southwest Illinois overnight where we may see a wintry mix of precip including rain/freezing rain and snow. But still enough spread in the ensemble members in this area to hold off making any significant changes to the grids with respect to precip type overnight, but that will have to be watched. Quick look at the 00z NAM-WRF showing a trend closer to what the current GFS model suggests with the better threat for accumulating snows over the northeast half of the forecast area...roughly around 1 inch with some isolated 2 inch reports possible east of I-57. Gradient remains tight across central Illinois so even though the snow accumulations will be minor, any snowfall with the gusty winds will produce areas of blowing snow creating slippery travel conditions overnight. WRF ensembles suggest a quick exit to the snow...roughly in the 07z-10z time frame...which the current HRRR is latching on to. For now, will hold on to the current idea of ending the snow from northwest to southeast Saturday morning with actually a lull in the precip chances thru the remainder of the day Saturday before another clipper starts to affect our area after midnight Sat night/Sun morning. We have seen our overnight lows reached early this evening as the persistent south to southwest low level flow will keep temps steady or slowly rising overnight as the trof/wind shift line out to our west tracks thru our area in the morning. Readings over far west central Illinois may hover around 35 for several hours this evening into the early morning hours before the boundary shifts thru the area towards dawn. Other than the usual tweaking of hourly temperatures in the grids for this evening, the current ZFP has a good handle on the weather trends this evening, so will not be needing an update at this time. Smith && .AVIATION... ISSUED 535 PM CST Fri Jan 24 2014 Main forecast concern will be the timing of the snow into the forecast area this evening and how quickly the cigs drop down to MVFR or lower. Looks as if the timing of the snow from north to south will be from 02z-04z at PIA and BMI and then from 04z to 06z for points further south and east. VFR cigs will lower to MVFR cigs once the snow begins with our northern TAF sites (PIA, BMI and CMI) seeing tempo IFR cigs in some of the brief bursts of heavier snow that will accompany a trof/wind shift line late tonight. Most of the snow should be east of the TAF sites by 14z with skies gradually clearing from northwest to southeast in the 15z-18z time frame with VFR conditions expected in the afternoon. Surface winds will be gusty tonight but not as strong as today`s winds. South to southwest winds will range from 13 to 18kts with gusts of 25 to 30 kts possible. Look for winds to shift into the northwest in the 10z-14z time frame Saturday with gusty winds once again expected, especially during the afternoon with a few locations seeing gusts around 30 kts at times. Smith && .PREV DISCUSSION... ISSUED 221 PM CST Fri Jan 24 2014 Plenty of winter-weather challenges with this forecast package...including chances for accumulating snow tonight and again Saturday night, followed by bitterly cold conditions early next week. SHORT TERM...Tonight through Tuesday Strong southerly winds have developed across central Illinois this afternoon in response to a tightening gradient between high pressure centered over the Gulf Coast and an approaching cold front dropping into the Dakotas. Winds will remain strong and gusty this evening, with forecast soundings and numeric guidance suggesting continued gusts to between 30 and 35mph. Thanks to the steady southerly flow and increasing cloud cover, low temperatures for tonight will be achieved early this evening followed by rising temps overnight. As low pressure tracks eastward across Hudson Bay, a trailing cold front will sweep into the area tonight. Models are in agreement that a period of light snow will accompany the front, although with only weak upper support and limited moisture, accumulations will remain light. Most locations will pick up 1 inch of snow or less tonight, with locations north of the I-74 corridor perhaps measuring as much as 1 to 2 inches. Aside from the falling snow, strong winds will continue through the night causing considerable blowing snow and reduced visibilities. While the light precipitation will be quick to exit toward dawn, brisk northwesterly winds gusting over 30 mph behind the departing front will persist into Saturday. As a result, have opted to extend the Winter Weather Advisory until 9 AM Saturday. Depending on how much snow falls overnight and how much blowing/drifting occurs, the advisory may even need to be extended further into Saturday. After a brief lull during the day Saturday, the next clipper system will quickly approach from the northwest by Saturday night. Model trends have slowed this system just a bit, so have removed POPs during the evening. Models are still not in perfect agreement regarding the exact track of the upper wave, with the GFS remaining further south than the NAM. Consensus tracks the 500mb vort max along/near the I-80 corridor, which would generally keep the heaviest snow just north of the KILX CWA late Saturday night into Sunday morning. Given strong upper dynamics and track across north-central Illinois, have increased POPs with this system. Will carry categorical POPs along/north of I-74 tapering down to just low chance along/south of I-70. Accumulations will once again be on the light side across much of central Illinois, with most areas seeing 1 inch or less. Further north, higher totals of 2 to 3 inches will be possible along/north of I-74 depending upon the exact track of the clipper. Once this system exits the region, mild/dry weather will be the rule Sunday afternoon ahead of an Arctic cold front approaching from the north. Sunday will be the warmest day of the forecast period, with high temperatures reaching the upper 30s and lower 40s. Lift along cold front will be strong enough to support snow flurries or perhaps a few snow-showers Sunday evening, followed by windy and sharply colder conditions overnight. As has been advertised for several days, a considerable chunk of polar air will settle southward across much of the eastern CONUS early next week, resulting in some of the coldest readings thus far this winter. Numeric guidance is suggesting high temperatures on Monday remaining in the single digits and lows Monday night plunging to as low as the teens below zero in many areas. These extremely cold temperatures combined with brisk northwesterly winds will create wind-chill values of 25 below to 35 below zero at times from late Sunday night through Tuesday. Wind chill advisories and/or warnings will be needed as the time nears. LONG TERM...Wednesday through Friday Aside from a generally dry frontal passage on Thursday, the extended will be characterized by dry weather with a gradual warming trend. After sub-zero temperatures early Wednesday morning, an increasingly zonal upper flow pattern will allow temps to warm into the upper 20s and lower 30s by Friday. && .ILX WATCHES/WARNINGS/ADVISORIES... WINTER WEATHER ADVISORY until 9 AM CST Saturday FOR ILZ027>031- 036>038-041>046-048-053>057-063. && $$
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1006 PM EST SAT JAN 25 2014 .UPDATE... THE NEAR TERM AND AVIATION SECTIONS HAVE BEEN UPDATED BELOW. && .SYNOPSIS... ISSUED AT 326 PM EST SAT JAN 25 2014 A WARM FRONT WILL SLIDE EAST ACROSS CENTRAL INDIANA ON SUNDAY WHICH WILL RESULT IN SNOW ACCUMULATION WITH THE HIGHEST AMOUNTS NEAR AND NORTH OF INTERSTATE 74 SOUTHEAST OF INDIANAPOLIS AND NEAR AND NORTH OF INTERSTATE 70 NORTHWEST OF INDIANAPOLIS. THE BLOWING SNOW WILL SUBSIDE OVERNIGHT ONLY TO RETURN ON SUNDAY AND SUNDAY NIGHT. THE BITTER COLD WILL ALSO RETURN BEHIND AN ARCTIC FRONT OVERNIGHT SUNDAY NIGHT THROUGH WEDNESDAY. DRY WEATHER IS EXPECTED THE FIRST HALF OF NEXT WEEK UNDER THE INFLUENCE OF THE ARCTIC HIGH. THEN...SNOW CHANCES WILL RETURN BY THURSDAY NIGHT WITH TEMPERATURES WARMING TO NEAR NORMAL NEXT WEEKEND. && .NEAR TERM /TONIGHT THROUGH SUNDAY NIGHT/... ISSUED AT 1006 PM EST SAT JAN 25 2014 HIGH PRESSURE RIDGE HAS BROUGHT CLEAR SKIES AND FINALLY A BREAK FROM THE RELENTLESS WINDS EXPERIENCED THROUGHOUT THE DAY TODAY. TEMPS HAD TUMBLED QUICKLY IN THE ARCTIC AIRMASS THIS EVENING WITH TEMPS GENERALLY IN THE SINGLE DIGITS AND TEENS AS OF 03Z. ENDLESS STREAM OF CLIPPERS CONTINUE WITH THE NEXT ONE RAPIDLY DROPPING THROUGH THE DAKOTAS THIS EVENING. MID AND HIGH LEVEL CLOUDS AHEAD OF THIS SYSTEM WILL QUICKLY EXPAND BACK ACROSS THE REGION AFTER MIDNIGHT AS THE SURFACE WAVE APPROACHES. HAVE SOME CONCERN THAT DRIER AIR WITHIN THE BOUNDARY LAYER WILL LIMIT SNOWFALL A BIT AS THIS SYSTEM SWINGS INTO THE REGION EARLY SUNDAY. HAVE BACKED OFF ON ONSET OF LIGHT SNOW AND ACCUMS BETWEEN 09-12Z...AS MODEL SOUNDINGS HINT AT THE DRY LAYER WITHIN THE BOUNDARY LAYER NOT BEING ERODED COMPLETELY. WHILE DRIER AIR WILL LIMIT SNOWFALL INTENSITY... RATIOS WILL BE UP IN THE 15-18 TO 1 RANGE WHICH WILL COMPENSATE A BIT. 00Z NAM AND RAP HAVE BOTH COME IN FURTHER NORTH WITH THE MAIN SWATH OF SNOW LATE TONIGHT AND SUNDAY MORNING...AND EXPECT PRIOR TO DAYBREAK LIGHT SNOW WILL PRIMARILY BE CONFINED TO AREAS ALONG AND NORTH OF I-70. TEMPS SHOULD BOTTOM OUT AROUND 06-07Z BEFORE BEGINNING TO RISE IN RESPONSE TO CLOUDS AND EVAPORATIVE COOLING PROCESSES AS THE PRECIP ARRIVES. FORECAST LOWS LOOKED REASONABLE AND DID NOT CHANGE. PERTINENT PARTS OF THE AFTERNOON NEAR TERM DISCUSSION FOLLOWS. MODELS ARE IN GOOD AGREEMENT WITH THIS EVER EVOLVING AND HISTORIC JANUARY 2014 WINTER. A WARM FRONT WILL SLIDE EAST ACROSS THE AREA SUNDAY AS WILL A CLIPPER THAT WILL DROP SOUTHEAST IN THE FAST NORTHWEST FLOW. 285K ISENTROPIC ANALYSIS WAS SHOWING LOWERING CONDENSATION PRESSURE DEFICITS AFTER 09Z SPREADING FROM WEST TO EAST ALONG WITH STRONG ISENTROPIC LIFT THROUGH AROUND 15Z. MIXING RATIOS WERE FROM 2 TO 3 G/KG WHICH FOR A SOLID 12 HOUR SNOW WOULD NORMALLY PRODUCE AROUND 4 TO 6 INCHES OF SNOW. HOWEVER...WITH THE BEST LIFT AND DEEPEST MOISTURE ONLY EXPECTED TO LAST 6 HOURS...2 TO 3 INCHES LOOKS GOOD MAINLY NEAR AND NORTH OF INTERSTATE 74 TO THE SOUTHEAST OF INDIANAPOLIS AND NORTH OF INTERSTATE 70 TO THE NORTHWEST OF INDY. AMOUNTS WILL BE LESSER TO THE SOUTH WITH LESS THAN AN INCH SOUTHWEST. SOUTHWEST AREAS COULD ALSO SEE A MIX OF THE SNOW WITH RAIN WHICH COULD FURTHER REDUCE AMOUNTS. HOWEVER...WENT ON THE COLD SIDE OF MOS WITH THE SNOW PACK AND TRENDS AND DID NOT INCLUDE ANY MIX DOWN THERE AS OF YET. WILL GO WITH A WINTER WEATHER ADVISORY FOR SNOW AND BLOWING SNOW FROM 4 AM SUNDAY TO 7 AM MONDAY SINCE BLOWING SNOW WILL ALSO BE A FACTOR WITH WINDS GUSTING TO 30 MPH. WIND CHILLS WILL ONCE AGAIN FALL WELL BELOW ZERO OVERNIGHT SUNDAY NIGHT...ACROSS OUR NORTHWEST COUNTIES ESPECIALLY...AS THE ARCTIC FRONT SWEEPS THROUGH. WIND CHILLS BELOW 15 DEGREES BELOW ZERO ARE LIKELY THERE BEFORE 12Z MONDAY...SO STARTED A WIND CHILL WATCH AT 10Z MONDAY. WE INCLUDED THE WHOLE FORECAST AREA AS THE SHORT TERM WILL SHOW THAT ALL COUNTIES SEE WIND CHILLS WELL BELOW NEGATIVE 15 BY MONDAY NIGHT. WILL GO ON THE LOW SIDE OF GUIDANCE FOR TEMPERATURES SUNDAY NIGHT BASED ON TRENDS AND SNOW PACK. && .SHORT TERM /MONDAY THROUGH TUESDAY/... ISSUED AT 326 PM EST SAT JAN 25 2014 TEMPERATURES...AND WIND CHILLS WILL BE THE MAIN ISSUE WITH THE SHORT TERM. MODELS IN GOOD AGREEMENT THAT THE AXIS OF ARCTIC HIGH PRESSURE WILL BE ALONG THE MISSISSIPPI VALLEY MONDAY NIGHT AND OHIO VALLEY BY TUESDAY. SURFACE PRESSURE GRADIENT WILL BE STRONG JUST AHEAD OF THE RIDGE...ON MONDAY WITH GUSTS IN THE 20S. THEN...WINDS WILL DIE OFF A BUT MONDAY NIGHT. HOWEVER...WITH OVERNIGHT LOWS EXPECTED TO REACH 15 DEGREES BELOW ZERO OR LOWER UNDER CLEARING SKIES...WIND CHILLS WILL BE NEAR MINUS 40 DEGREES ACROSS OUR FAR NORTH. THE SOUTH WILL ALSO BE COLD BUT NOT QUITE AS COLD WITH LOWS 5 TO 10 DEGREES BELOW ZERO POSSIBLE AND WIND CHILLS TO MINUS 20. TEMPERATURES AND WIND CHILLS SHOULD BE VERY NEAR WHAT THEY WERE AFTER THE SNOW STORM OF JANUARY 5TH OF THIS YEAR. DESPITE PLENTY OF SUNSHINE...WITH THE COLDEST 925 MILLIBAR TEMPERATURES OF 27 BELOW ON MONDAY NIGHT AND TUESDAY...NORTHERN COUNTIES WILL PROBABLY NOT EVEN WARM UP TO ZERO ON TUESDAY. && .LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... ISSUED AT 231 PM EST SAT JAN 25 2014 A SLOW WARM UP IS PROGGED FOR THE EXTENDED. TEMPERATURES START OUT BITTERLY COLD TUESDAY NIGHT WITH LOWS AGAIN SEVERAL DEGREES BELOW ZERO. HOWEVER ON WEDNESDAY THE UPPER PATTERN STARTS TO FLATTEN OUT AND TEMPERATURES WILL SLOWLY MODERATE THROUGH SATURDAY WITH HIGHS WEDNESDAY IN THE TEENS AND THEN 20S ON THURSDAY AND FRIDAY. GFS AND ECMWF CONTINUE TO SHOW A WAVE MOVING THROUGH THURSDAY THAT WILL BRING SNOW TO THE AREA SO WENT WITH CHANCE POPS GIVEN FROM INITIALIZATION. BY FRIDAY NIGHT/SATURDAY LOOKS LIKE WARM ADVECTION AND A SYSTEM MOVING UP FROM THE CENTRAL PLAINS WITH ACCESS TO MOISTURE. UNCERTAINTY CONCERNING HOW QUICKLY THE COLUMN WILL WARM AND SATURATE SO WILL INCLUDE A CHANCE FOR A RAIN SNOW MIX. MADE MINOR MODIFICATIONS TO THE INITIALIZATION FOR COLLABORATION PURPOSES. && .AVIATION /DISCUSSION FOR THE 260300Z TAF UPDATE/... ISSUED AT 1006 PM EST SAT JAN 25 2014 STILL SEEING SPORADIC WIND GUSTS TO 20-25KTS BUT IN GENERAL...WINDS HAVE GREATLY DIMINISHED OVER THE LAST FEW HOURS. EXPECT WINDS TO CONTINUE TO WEAKEN...BECOMING VARIABLE IN DIRECTION. EXPECT MOSTLY CLEAR SKIES THROUGH 06Z WITH CLOUDS INCREASING AHEAD OF THE FAST APPROACHING CLIPPER. 00Z DISCUSSION FOLLOWS. VFR THROUGH THE FIRST 12 OR SO HOURS OF THE PERIOD...WITH MVFR OR WORSE CONDITIONS IN THE NEXT CLIPPER SYSTEM THEREAFTER. WINDS/BLOWING SNOW REMAIN A PROBLEM...BUT GUSTS ARE STARTING TO DISSIPATE. WILL CARRY THEM FOR ANOTHER HOUR AT THE OUTLYING SITES AND ANOTHER TWO HOURS AT IND. OVERNIGHT...WINDS WILL GRADUALLY BECOME SOUTHERLY...BY AROUND 09-12Z. SNOW FROM NEXT SYSTEM WILL LIKELY START AROUND 12Z ACROSS THE AREA...WITH MVFR OR WORSE CONDITIONS DEVELOPING. WINDS WILL BECOME GUSTY YET AGAIN...BUT LIKELY ONLY IN THE MID TO HIGH 20KT RANGE. MAY GUST A BIT STRONGER AFTER THE ARCTIC FRONT PASSES. && .IND WATCHES/WARNINGS/ADVISORIES... WIND CHILL WATCH FROM LATE SUNDAY NIGHT THROUGH WEDNESDAY MORNING FOR INZ021-028>031-035>049-051>057-060>065-067>072. WINTER WEATHER ADVISORY FROM 4 AM SUNDAY TO 7 AM EST MONDAY FOR INZ021-028>031-035>049-057. && $$ SYNOPSIS...MK NEAR TERM...MK/RYAN SHORT TERM...MK LONG TERM...CP AVIATION...NIELD/RYAN VISIT US AT HTTP://WWW.WEATHER.GOV/IND FOLLOW US ON TWITTER AND YOUTUBE AT: WWW.TWITTER.COM/NWSINDIANAPOLIS WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS DES MOINES IA
1201 PM CST FRI JAN 24 2014 ...UPDATED FOR AVIATION DISCUSSION... .SHORT TERM /TODAY/... ISSUED AT 435 AM CST FRI JAN 24 2014 STRONG WAA LOOKS TO CONTINUE THROUGH MUCH OF THE DAY TODAY HELPING TO PUSH MAX TEMPS ROUGHLY 30 DEGREES WARMER THAN THURSDAY HIGH TEMPS. THE LATEST ECMWF MOS GUIDANCE HAS BEEN THE WARMEST WITH TODAYS HIGH TEMPS OVER THE PAST SEVERAL RUNS...AND HAS BEEN THE BEST GUIDANCE LATELY WITH THESE QUICK ONE DAY WARM-UPS. IF MIXED TO JUST 900MB...TEMPS LOOK TO BE IN THE LOWER TO MIDDLE 40S ACROSS MUCH OF CENTRAL TO SOUTHWEST IOWA. SO LEANED TOWARD THE ECMWF FOR MAX TEMPS TODAY WHICH RESULTED IN WARMING TEMPS UP 5 TO 7 DEGREES ACROSS THE BOARD. PRESSURE GRADIENT REMAINS STRONG THROUGHOUT THE DAY AND THE SOUTHEAST LOOKS TO MIX SLIGHTLY DEEPER WITH BETTER SUNSHINE...SO WIND GUSTS MAY TEETER ON ADVISORY LEVEL FOR A SHORT TIME FRAME LATE THIS MORNING AND INTO THE EARLY AFTERNOON. A QUICK SHOT OF MID-LEVEL THETA-E ADVECTION WILL MOVE ACROSS THE STATE THIS MORNING AND MAY BRING A FEW LIGHT SNOW SHOWERS OR FLURRIES TO THE NORTHERN TIERS OF FORECAST THRU 18Z. HIRES ARW/NMM WRF MODELS BARELY HAVE ANY PRECIP MOVING ACROSS THE NORTHEAST THIS MORNING AND THE LATEST HOPWRF (24.06Z) AND HRRR (24.06Z) ARE IN GOOD AGREEMENT WITH THEM. ONLY HAVE SLIGHT POPS GOING FROM 13-17Z AND KEPT MENTION OF BLOWING SNOW ACROSS THE NORTH WITH THE STRONG SOUTHWEST FLOW. NEXT SHORTWAVE LOOKS TO BRING A BETTER CHANCE OF PRECIP...BUT PROGRESSION HAS SLOWED DOWN FROM PREVIOUSLY THOUGHT. THE HIRES ARW/NMM WRF MODELS HAVE SOME LIGHT PRECIP MOVING INTO NORTHERN IOWA BY 22Z OR SHORTLY AFTER. SO WENT DRY 18Z TO 21Z AND CONFINED POPS TO THE NORTHERN TWO TIERS OF IOWA COUNTIES. MCW SOUNDING QUICKLY BECOMES DEEPLY SATURATED BY AROUND 00Z AS A FAIR AMOUNT OF ISENTROPIC LIFT AND THETA-E ADVECTION MOVE INTO NORTHERN IOWA LATE THIS AFTERNOON. HAVE SNOW/RAIN FORECAST FOR THE NORTHWEST...AS SURFACE TEMPS LOOK TO WARM UP ENOUGH TO SEE SNOW MELT PRIOR TO REACHING THE GROUND. .LONG TERM /TONIGHT THROUGH THURSDAY/... ISSUED AT 435 AM CST FRI JAN 24 2014 WEATHER WILL BE VERY ACTIVE INTO EARLY NEXT WEEK WITH SEVERAL SIGNIFICANT HEADLINE EVENTS INCREASINGLY LIKELY...INCLUDING WHAT MAY BE A BLIZZARD LATE SUNDAY. INITIAL SYSTEM TONIGHT...WHICH WILL NOT BE THE BIGGEST CONCERN...SHOULD BE ENTERING NRN IA AT BEGINNING OF THE PERIOD AS HUDSON BAY LONG WAVE TROUGH DIGS INTO THE GREAT LAKES TONIGHT. FORCING WITH THIS SYSTEM IS DEEP BUT SOMEWHAT PATCHY WITH NAM LIFT MORE BULLISH THAN GFS OR ECMWF. WITH FAST MOVEMENT AND FOLLOWING STRONG SUBSIDENCE...ANY UPWARD MOTION WILL BE FLEETING. AFOREMENTIONED WARMER SOLUTIONS BRING MUCH OF THE AREA ABOVE OR AT LEAST NEAR THE FREEZING MARK MAKING THE PREDOMINATE PRECIP TYPE RAIN SW AND A RAIN/SNOW MIX FARTHER NORTHEAST. THESE WARMER TEMPS WILL ALSO RAISE LOWEST 1KM TEMPS HIGH ENOUGH TO LOWER SNOW RATIOS SO ONLY EXPECT ACCUMS OF AN INCH OR LESS FAR NORTHEAST. STRONG SUBSIDENCE WILL THEN FOLLOW SAT WITH BRISK NORTHWEST WINDS AND COLD ADVECTION RESULTING IN LITTLE DIURNAL REBOUND. IN FACT...NON-DIURNAL TRENDS WILL BE THE NORM THROUGH THE WEEKEND AND MAKE HIGHS AND LOWS PROBLEMATIC WITH LOWER/RISING TEMPS AT TIMES CENTERED AROUND DAYS/NIGHTS RESPECTIVELY. ATTENTION WILL THEN QUICKLY TURN UPSTREAM WITH CLIPPER SYSTEM RAPIDLY INCREASING CLOUDS AND PRECIP NW-SE. FORCING WITH THIS SYSTEM WILL BE QUITE DEEP...AND ALTHOUGH THERE WILL BE DECENT KINEMATIC LIFT...IT SHOULD BE DOMINATED BY STRONG AND IMPRESSIVE THERMODYNAMIC FORCING /THETA-E ADVECTION AND FRONTOGENESIS/. THIS DEEP LIFT AND COOLER COLUMN TEMPS SHOULD PRODUCE HIGHER SNOW RATIOS THAN TONIGHT...WELL INTO THE TEENS. RATIOS COULD BE EVEN HIGHER...OVER 20...BUT THE MAX LIFT WITH THIS SYSTEM LOOKS TO BE 1-2KM AND MAINLY BELOW THE DENDRITIC GROWTH ZONE. THESE SOMEWHAT RESTRICTED RATIOS AND FAST SYSTEM MOVEMENT...LIKELY SNOWING LESS THAN SIX HOURS AT ANY PARTICULAR LOCATION...SHOULD GENERALLY KEEP SNOW AMOUNTS IN THE ONE TO THREE INCH RANGE OVER THE NE HALF OF THE FORECAST AREA. LOCALLY HIGHER AMOUNTS MAY OCCUR IN THE FAR NE CORNERS AS WELL /MASON CITY/WATERLOO NORTH/. CONFIDENCE IS STILL NOT THE GREATEST ON AMOUNTS HOWEVER AS ECMWF AND GFS HAVE NOW FLIP-FLOPPED THEIR SNOW AXIS EMPHASIS. ECMWF NOW EMPHASIZES MORE NELY TRACK. SNOW AMOUNTS WILL NOT BE BIG IMPACT WITH THIS SYSTEM HOWEVER WITH THE GREATEST IMPACTS NOT SEEN UNTIL SUN AND SUN EVENING. MAY SEE SOME SPOTTY SNOW SHOWERS INTO SUN WITH LITTLE ADDITIONAL ACCUMS...BUT LARGER PROBLEM WILL BE INCREASING WINDS AND A BIG CHANGE FROM PREVIOUS FORECAST. BUFKIT SOUNDINGS SHOW A RELATIVELY DEEP MIXED LAYER WITH GUSTS OFTEN 40-55KTS BY THE AFTERNOON AND EARLY EVENING...ESPECIALLY WEST AND NORTH. NO HEADLINES AS OF YET IN THIS PERIOD...BUT OPTIONS MAY ULTIMATELY RANGE FROM WIND ADVISORIES AND/OR WARNINGS TO FULL FLEDGED BLIZZARD WARNINGS IF FORECASTED SNOWFALL DEVELOPS. THIS SYSTEM MAY BRING SOMEWHAT OF A WORSE CASE SCENARIO WITH A MYRIAD OF HAZARDS INTO MON. ALTHOUGH TEMPS NE WILL REMAIN COLD ENOUGH...READINGS MAY SURGE CLOSE TO THE FREEZING MARK NW-SE ALONG THE SWRN FRINGE OF SNOW ACCUMS WITH SOME MINOR MELTING FOLLOWED BY A FLASH FREEZE WITH SHARP TEMP DROP LATER IN THE EVENING. ATTENTION WILL THEN TURN TO YET ANOTHER ROUND OF BITTER ARCTIC COLD WITH WIDESPREAD WIND CHILL ISSUES AND CONTINUED BLOWING SNOW NE HALF. SERIOUS...LIFE THREATENING TRAVEL CONDITIONS MAY OCCUR NE HALF MON MORNING. WINDS WILL NOT BE AS STRONG AS SUNDAY...BUT WILL NOT DIMINISH SUFFICIENTLY TO PRECLUDE CONTINUED BLOWING AND DRIFTING AND MAKE IT DIFFICULT FOR ROAD CREWS TO MAKE ANY HEADWAY...ASSUMING FORECAST SNOW AMOUNTS OF COURSE. THIS WOULD BE COINCIDENT WITH WIDESPREAD TEMPS IN THE SINGLE DIGITS AND TEENS BELOW ZERO...AND WIND CHILLS 25 TO 45 BELOW. WITH LITTLE CHANGE IN PATTERN INTO TUE...AND PERSISTENT NWLY WINDS...TEMPS AT MASON CITY FOR INSTANCE MAY NOT TOP ZERO UNTIL WEDNESDAY. THIS COULD RESULT IN A 30 HOUR PERIOD WITH AT LEAST MINOR BLOWING SNOW AND WARNING CRITERIA WIND CHILLS /-30F/. NEEDLESS TO SAY...THE BEGINNING OF NEXT WEEK WILL NEED CONSIDERABLE ATTENTION IN THE COMING DAYS. REMAINDER OF THE PERIOD LOOKS TO REMAIN COLD WITH CONTINUED BELOW NORMAL TEMPS. EXTENDED PATTERN LOOKS SOMEWHAT MORE INACTIVE THANKFULLY WITH ONLY PRECIP WINDOW AROUND WED NIGHT...MAINLY DUE TO ECMWF WHICH SUGGESTS A LOBE OF FORCING ACCOMPANYING YET ANOTHER COLD FRONTAL PASSAGE TO END THE WORK WEEK. && .AVIATION...24/18Z ISSUED AT 1145 AM CST FRI JAN 24 2014 SOUTHWESTERLY WINDS AT THE BEGINNING OF THE TAF PERIOD WILL BECOME NORTHWESTERLY BY 12Z SAT. WINDS GENERALLY TO STAY IN THE 15 TO 20 KT RANGE AND GUSTS TO IN THE 25 TO 30 KT RANGE. STARTING AROUND 22Z FRI...WINTRY PRECIP WILL START OVER NORTHERN TAF SITES...REACHING BOTH KDSM AND KALO BY AROUND 23Z AND KOTM BY 01Z SAT. KMCW AND KALO WILL HAVE -SN...KFOD -RASN...AND BOTH KDSM AND KOTM -RN. THE STRONG WINDS WILL BRING REDUCED VISIBILITIES TO KALO AND KMCW DURING PERIODS OF SNOW. CEILINGS TO LOWER TO IFR AS PRECIP MOVES IN. SKIES CLEARING BY 12Z SAT FOR ALL TAF SITES. && .DMX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...PODRAZIK LONG TERM...SMALL AVIATION...KOTENBERG
AREA FORECAST DISCUSSION
NWS DES MOINES IA
543 AM CST FRI JAN 24 2014 ...UPDATED AVIATION DISCUSSION... .SHORT TERM /TODAY/... ISSUED AT 435 AM CST FRI JAN 24 2014 STRONG WAA LOOKS TO CONTINUE THROUGH MUCH OF THE DAY TODAY HELPING TO PUSH MAX TEMPS ROUGHLY 30 DEGREES WARMER THAN THURSDAY HIGH TEMPS. THE LATEST ECMWF MOS GUIDANCE HAS BEEN THE WARMEST WITH TODAYS HIGH TEMPS OVER THE PAST SEVERAL RUNS...AND HAS BEEN THE BEST GUIDANCE LATELY WITH THESE QUICK ONE DAY WARM-UPS. IF MIXED TO JUST 900MB...TEMPS LOOK TO BE IN THE LOWER TO MIDDLE 40S ACROSS MUCH OF CENTRAL TO SOUTHWEST IOWA. SO LEANED TOWARD THE ECMWF FOR MAX TEMPS TODAY WHICH RESULTED IN WARMING TEMPS UP 5 TO 7 DEGREES ACROSS THE BOARD. PRESSURE GRADIENT REMAINS STRONG THROUGHOUT THE DAY AND THE SOUTHEAST LOOKS TO MIX SLIGHTLY DEEPER WITH BETTER SUNSHINE...SO WIND GUSTS MAY TEETER ON ADVISORY LEVEL FOR A SHORT TIME FRAME LATE THIS MORNING AND INTO THE EARLY AFTERNOON. A QUICK SHOT OF MID-LEVEL THETA-E ADVECTION WILL MOVE ACROSS THE STATE THIS MORNING AND MAY BRING A FEW LIGHT SNOW SHOWERS OR FLURRIES TO THE NORTHERN TIERS OF FORECAST THRU 18Z. HIRES ARW/NMM WRF MODELS BARELY HAVE ANY PRECIP MOVING ACROSS THE NORTHEAST THIS MORNING AND THE LATEST HOPWRF (24.06Z) AND HRRR (24.06Z) ARE IN GOOD AGREEMENT WITH THEM. ONLY HAVE SLIGHT POPS GOING FROM 13-17Z AND KEPT MENTION OF BLOWING SNOW ACROSS THE NORTH WITH THE STRONG SOUTHWEST FLOW. NEXT SHORTWAVE LOOKS TO BRING A BETTER CHANCE OF PRECIP...BUT PROGRESSION HAS SLOWED DOWN FROM PREVIOUSLY THOUGHT. THE HIRES ARW/NMM WRF MODELS HAVE SOME LIGHT PRECIP MOVING INTO NORTHERN IOWA BY 22Z OR SHORTLY AFTER. SO WENT DRY 18Z TO 21Z AND CONFINED POPS TO THE NORTHERN TWO TIERS OF IOWA COUNTIES. MCW SOUNDING QUICKLY BECOMES DEEPLY SATURATED BY AROUND 00Z AS A FAIR AMOUNT OF ISENTROPIC LIFT AND THETA-E ADVECTION MOVE INTO NORTHERN IOWA LATE THIS AFTERNOON. HAVE SNOW/RAIN FORECAST FOR THE NORTHWEST...AS SURFACE TEMPS LOOK TO WARM UP ENOUGH TO SEE SNOW MELT PRIOR TO REACHING THE GROUND. .LONG TERM /TONIGHT THROUGH THURSDAY/... ISSUED AT 435 AM CST FRI JAN 24 2014 WEATHER WILL BE VERY ACTIVE INTO EARLY NEXT WEEK WITH SEVERAL SIGNIFICANT HEADLINE EVENTS INCREASINGLY LIKELY...INCLUDING WHAT MAY BE A BLIZZARD LATE SUNDAY. INITIAL SYSTEM TONIGHT...WHICH WILL NOT BE THE BIGGEST CONCERN...SHOULD BE ENTERING NRN IA AT BEGINNING OF THE PERIOD AS HUDSON BAY LONG WAVE TROUGH DIGS INTO THE GREAT LAKES TONIGHT. FORCING WITH THIS SYSTEM IS DEEP BUT SOMEWHAT PATCHY WITH NAM LIFT MORE BULLISH THAN GFS OR ECMWF. WITH FAST MOVEMENT AND FOLLOWING STRONG SUBSIDENCE...ANY UPWARD MOTION WILL BE FLEETING. AFOREMENTIONED WARMER SOLUTIONS BRING MUCH OF THE AREA ABOVE OR AT LEAST NEAR THE FREEZING MARK MAKING THE PREDOMINATE PRECIP TYPE RAIN SW AND A RAIN/SNOW MIX FARTHER NORTHEAST. THESE WARMER TEMPS WILL ALSO RAISE LOWEST 1KM TEMPS HIGH ENOUGH TO LOWER SNOW RATIOS SO ONLY EXPECT ACCUMS OF AN INCH OR LESS FAR NORTHEAST. STRONG SUBSIDENCE WILL THEN FOLLOW SAT WITH BRISK NORTHWEST WINDS AND COLD ADVECTION RESULTING IN LITTLE DIURNAL REBOUND. IN FACT...NON-DIURNAL TRENDS WILL BE THE NORM THROUGH THE WEEKEND AND MAKE HIGHS AND LOWS PROBLEMATIC WITH LOWER/RISING TEMPS AT TIMES CENTERED AROUND DAYS/NIGHTS RESPECTIVELY. ATTENTION WILL THEN QUICKLY TURN UPSTREAM WITH CLIPPER SYSTEM RAPIDLY INCREASING CLOUDS AND PRECIP NW-SE. FORCING WITH THIS SYSTEM WILL BE QUITE DEEP...AND ALTHOUGH THERE WILL BE DECENT KINEMATIC LIFT...IT SHOULD BE DOMINATED BY STRONG AND IMPRESSIVE THERMODYNAMIC FORCING /THETA-E ADVECTION AND FRONTOGENESIS/. THIS DEEP LIFT AND COOLER COLUMN TEMPS SHOULD PRODUCE HIGHER SNOW RATIOS THAN TONIGHT...WELL INTO THE TEENS. RATIOS COULD BE EVEN HIGHER...OVER 20...BUT THE MAX LIFT WITH THIS SYSTEM LOOKS TO BE 1-2KM AND MAINLY BELOW THE DENDRITIC GROWTH ZONE. THESE SOMEWHAT RESTRICTED RATIOS AND FAST SYSTEM MOVEMENT...LIKELY SNOWING LESS THAN SIX HOURS AT ANY PARTICULAR LOCATION...SHOULD GENERALLY KEEP SNOW AMOUNTS IN THE ONE TO THREE INCH RANGE OVER THE NE HALF OF THE FORECAST AREA. LOCALLY HIGHER AMOUNTS MAY OCCUR IN THE FAR NE CORNERS AS WELL /MASON CITY/WATERLOO NORTH/. CONFIDENCE IS STILL NOT THE GREATEST ON AMOUNTS HOWEVER AS ECMWF AND GFS HAVE NOW FLIP-FLOPPED THEIR SNOW AXIS EMPHASIS. ECMWF NOW EMPHASIZES MORE NELY TRACK. SNOW AMOUNTS WILL NOT BE BIG IMPACT WITH THIS SYSTEM HOWEVER WITH THE GREATEST IMPACTS NOT SEEN UNTIL SUN AND SUN EVENING. MAY SEE SOME SPOTTY SNOW SHOWERS INTO SUN WITH LITTLE ADDITIONAL ACCUMS...BUT LARGER PROBLEM WILL BE INCREASING WINDS AND A BIG CHANGE FROM PREVIOUS FORECAST. BUFKIT SOUNDINGS SHOW A RELATIVELY DEEP MIXED LAYER WITH GUSTS OFTEN 40-55KTS BY THE AFTERNOON AND EARLY EVENING...ESPECIALLY WEST AND NORTH. NO HEADLINES AS OF YET IN THIS PERIOD...BUT OPTIONS MAY ULTIMATELY RANGE FROM WIND ADVISORIES AND/OR WARNINGS TO FULL FLEDGED BLIZZARD WARNINGS IF FORECASTED SNOWFALL DEVELOPS. THIS SYSTEM MAY BRING SOMEWHAT OF A WORSE CASE SCENARIO WITH A MYRIAD OF HAZARDS INTO MON. ALTHOUGH TEMPS NE WILL REMAIN COLD ENOUGH...READINGS MAY SURGE CLOSE TO THE FREEZING MARK NW-SE ALONG THE SWRN FRINGE OF SNOW ACCUMS WITH SOME MINOR MELTING FOLLOWED BY A FLASH FREEZE WITH SHARP TEMP DROP LATER IN THE EVENING. ATTENTION WILL THEN TURN TO YET ANOTHER ROUND OF BITTER ARCTIC COLD WITH WIDESPREAD WIND CHILL ISSUES AND CONTINUED BLOWING SNOW NE HALF. SERIOUS...LIFE THREATENING TRAVEL CONDITIONS MAY OCCUR NE HALF MON MORNING. WINDS WILL NOT BE AS STRONG AS SUNDAY...BUT WILL NOT DIMINISH SUFFICIENTLY TO PRECLUDE CONTINUED BLOWING AND DRIFTING AND MAKE IT DIFFICULT FOR ROAD CREWS TO MAKE ANY HEADWAY...ASSUMING FORECAST SNOW AMOUNTS OF COURSE. THIS WOULD BE COINCIDENT WITH WIDESPREAD TEMPS IN THE SINGLE DIGITS AND TEENS BELOW ZERO...AND WIND CHILLS 25 TO 45 BELOW. WITH LITTLE CHANGE IN PATTERN INTO TUE...AND PERSISTENT NWLY WINDS...TEMPS AT MASON CITY FOR INSTANCE MAY NOT TOP ZERO UNTIL WEDNESDAY. THIS COULD RESULT IN A 30 HOUR PERIOD WITH AT LEAST MINOR BLOWING SNOW AND WARNING CRITERIA WIND CHILLS /-30F/. NEEDLESS TO SAY...THE BEGINNING OF NEXT WEEK WILL NEED CONSIDERABLE ATTENTION IN THE COMING DAYS. REMAINDER OF THE PERIOD LOOKS TO REMAIN COLD WITH CONTINUED BELOW NORMAL TEMPS. EXTENDED PATTERN LOOKS SOMEWHAT MORE INACTIVE THANKFULLY WITH ONLY PRECIP WINDOW AROUND WED NIGHT...MAINLY DUE TO ECMWF WHICH SUGGESTS A LOBE OF FORCING ACCOMPANYING YET ANOTHER COLD FRONTAL PASSAGE TO END THE WORK WEEK. && .AVIATION...24/12Z ISSUED AT 543 AM CST FRI JAN 24 2014 SOUTHWEST WINDS WILL CONTINUE TO INCREASE AND HAVE GUSTS NEAR 30 KNOTS THROUGH THE MORNING. NEXT ISSUE IS WITH QUICK SHORTWAVE TONIGHT TO BRING MVFR CIGS AND POTENTIALLY VIS FOR LIGHT SNOW/RAIN. SHOULD BE A BRIEF PERIOD OF MVFR VIS THIS EVENING...BUT STRATUS LOOKS TO STICK AROUND WITH THE STRONG CAA DEVELOPING OVERNIGHT TONIGHT. && .DMX WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SHORT TERM...PODRAZIK LONG TERM...SMALL AVIATION...PODRAZIK
AREA FORECAST DISCUSSION
NWS DES MOINES IA
435 AM CST FRI JAN 24 2014 .SHORT TERM /TODAY/... ISSUED AT 435 AM CST FRI JAN 24 2014 STRONG WAA LOOKS TO CONTINUE THROUGH MUCH OF THE DAY TODAY HELPING TO PUSH MAX TEMPS ROUGHLY 30 DEGREES WARMER THAN THURSDAY HIGH TEMPS. THE LATEST ECMWF MOS GUIDANCE HAS BEEN THE WARMEST WITH TODAYS HIGH TEMPS OVER THE PAST SEVERAL RUNS...AND HAS BEEN THE BEST GUIDANCE LATELY WITH THESE QUICK ONE DAY WARM-UPS. IF MIXED TO JUST 900MB...TEMPS LOOK TO BE IN THE LOWER TO MIDDLE 40S ACROSS MUCH OF CENTRAL TO SOUTHWEST IOWA. SO LEANED TOWARD THE ECMWF FOR MAX TEMPS TODAY WHICH RESULTED IN WARMING TEMPS UP 5 TO 7 DEGREES ACROSS THE BOARD. PRESSURE GRADIENT REMAINS STRONG THROUGHOUT THE DAY AND THE SOUTHEAST LOOKS TO MIX SLIGHTLY DEEPER WITH BETTER SUNSHINE...SO WIND GUSTS MAY TEETER ON ADVISORY LEVEL FOR A SHORT TIME FRAME LATE THIS MORNING AND INTO THE EARLY AFTERNOON. A QUICK SHOT OF MID-LEVEL THETA-E ADVECTION WILL MOVE ACROSS THE STATE THIS MORNING AND MAY BRING A FEW LIGHT SNOW SHOWERS OR FLURRIES TO THE NORTHERN TIERS OF FORECAST THRU 18Z. HIRES ARW/NMM WRF MODELS BARELY HAVE ANY PRECIP MOVING ACROSS THE NORTHEAST THIS MORNING AND THE LATEST HOPWRF (24.06Z) AND HRRR (24.06Z) ARE IN GOOD AGREEMENT WITH THEM. ONLY HAVE SLIGHT POPS GOING FROM 13-17Z AND KEPT MENTION OF BLOWING SNOW ACROSS THE NORTH WITH THE STRONG SOUTHWEST FLOW. NEXT SHORTWAVE LOOKS TO BRING A BETTER CHANCE OF PRECIP...BUT PROGRESSION HAS SLOWED DOWN FROM PREVIOUSLY THOUGHT. THE HIRES ARW/NMM WRF MODELS HAVE SOME LIGHT PRECIP MOVING INTO NORTHERN IOWA BY 22Z OR SHORTLY AFTER. SO WENT DRY 18Z TO 21Z AND CONFINED POPS TO THE NORTHERN TWO TIERS OF IOWA COUNTIES. MCW SOUNDING QUICKLY BECOMES DEEPLY SATURATED BY AROUND 00Z AS A FAIR AMOUNT OF ISENTROPIC LIFT AND THETA-E ADVECTION MOVE INTO NORTHERN IOWA LATE THIS AFTERNOON. HAVE SNOW/RAIN FORECAST FOR THE NORTHWEST...AS SURFACE TEMPS LOOK TO WARM UP ENOUGH TO SEE SNOW MELT PRIOR TO REACHING THE GROUND. .LONG TERM /TONIGHT THROUGH THURSDAY/... ISSUED AT 435 AM CST FRI JAN 24 2014 WEATHER WILL BE VERY ACTIVE INTO EARLY NEXT WEEK WITH SEVERAL SIGNIFICANT HEADLINE EVENTS INCREASINGLY LIKELY...INCLUDING WHAT MAY BE A BLIZZARD LATE SUNDAY. INITIAL SYSTEM TONIGHT...WHICH WILL NOT BE THE BIGGEST CONCERN...SHOULD BE ENTERING NRN IA AT BEGINNING OF THE PERIOD AS HUDSON BAY LONG WAVE TROUGH DIGS INTO THE GREAT LAKES TONIGHT. FORCING WITH THIS SYSTEM IS DEEP BUT SOMEWHAT PATCHY WITH NAM LIFT MORE BULLISH THAN GFS OR ECMWF. WITH FAST MOVEMENT AND FOLLOWING STRONG SUBSIDENCE...ANY UPWARD MOTION WILL BE FLEETING. AFOREMENTIONED WARMER SOLUTIONS BRING MUCH OF THE AREA ABOVE OR AT LEAST NEAR THE FREEZING MARK MAKING THE PREDOMINATE PRECIP TYPE RAIN SW AND A RAIN/SNOW MIX FARTHER NORTHEAST. THESE WARMER TEMPS WILL ALSO RAISE LOWEST 1KM TEMPS HIGH ENOUGH TO LOWER SNOW RATIOS SO ONLY EXPECT ACCUMS OF AN INCH OR LESS FAR NORTHEAST. STRONG SUBSIDENCE WILL THEN FOLLOW SAT WITH BRISK NORTHWEST WINDS AND COLD ADVECTION RESULTING IN LITTLE DIURNAL REBOUND. IN FACT...NON-DIURNAL TRENDS WILL BE THE NORM THROUGH THE WEEKEND AND MAKE HIGHS AND LOWS PROBLEMATIC WITH LOWER/RISING TEMPS AT TIMES CENTERED AROUND DAYS/NIGHTS RESPECTIVELY. ATTENTION WILL THEN QUICKLY TURN UPSTREAM WITH CLIPPER SYSTEM RAPIDLY INCREASING CLOUDS AND PRECIP NW-SE. FORCING WITH THIS SYSTEM WILL BE QUITE DEEP...AND ALTHOUGH THERE WILL BE DECENT KINEMATIC LIFT...IT SHOULD BE DOMINATED BY STRONG AND IMPRESSIVE THERMODYNAMIC FORCING /THETA-E ADVECTION AND FRONTOGENESIS/. THIS DEEP LIFT AND COOLER COLUMN TEMPS SHOULD PRODUCE HIGHER SNOW RATIOS THAN TONIGHT...WELL INTO THE TEENS. RATIOS COULD BE EVEN HIGHER...OVER 20...BUT THE MAX LIFT WITH THIS SYSTEM LOOKS TO BE 1-2KM AND MAINLY BELOW THE DENDRITIC GROWTH ZONE. THESE SOMEWHAT RESTRICTED RATIOS AND FAST SYSTEM MOVEMENT...LIKELY SNOWING LESS THAN SIX HOURS AT ANY PARTICULAR LOCATION...SHOULD GENERALLY KEEP SNOW AMOUNTS IN THE ONE TO THREE INCH RANGE OVER THE NE HALF OF THE FORECAST AREA. LOCALLY HIGHER AMOUNTS MAY OCCUR IN THE FAR NE CORNERS AS WELL /MASON CITY/WATERLOO NORTH/. CONFIDENCE IS STILL NOT THE GREATEST ON AMOUNTS HOWEVER AS ECMWF AND GFS HAVE NOW FLIP-FLOPPED THEIR SNOW AXIS EMPHASIS. ECMWF NOW EMPHASIZES MORE NELY TRACK. SNOW AMOUNTS WILL NOT BE BIG IMPACT WITH THIS SYSTEM HOWEVER WITH THE GREATEST IMPACTS NOT SEEN UNTIL SUN AND SUN EVENING. MAY SEE SOME SPOTTY SNOW SHOWERS INTO SUN WITH LITTLE ADDITIONAL ACCUMS...BUT LARGER PROBLEM WILL BE INCREASING WINDS AND A BIG CHANGE FROM PREVIOUS FORECAST. BUFKIT SOUNDINGS SHOW A RELATIVELY DEEP MIXED LAYER WITH GUSTS OFTEN 40-55KTS BY THE AFTERNOON AND EARLY EVENING...ESPECIALLY WEST AND NORTH. NO HEADLINES AS OF YET IN THIS PERIOD...BUT OPTIONS MAY ULTIMATELY RANGE FROM WIND ADVISORIES AND/OR WARNINGS TO FULL FLEDGED BLIZZARD WARNINGS IF FORECASTED SNOWFALL DEVELOPS. THIS SYSTEM MAY BRING SOMEWHAT OF A WORSE CASE SCENARIO WITH A MYRIAD OF HAZARDS INTO MON. ALTHOUGH TEMPS NE WILL REMAIN COLD ENOUGH...READINGS MAY SURGE CLOSE TO THE FREEZING MARK NW-SE ALONG THE SWRN FRINGE OF SNOW ACCUMS WITH SOME MINOR MELTING FOLLOWED BY A FLASH FREEZE WITH SHARP TEMP DROP LATER IN THE EVENING. ATTENTION WILL THEN TURN TO YET ANOTHER ROUND OF BITTER ARCTIC COLD WITH WIDESPREAD WIND CHILL ISSUES AND CONTINUED BLOWING SNOW NE HALF. SERIOUS...LIFE THREATENING TRAVEL CONDITIONS MAY OCCUR NE HALF MON MORNING. WINDS WILL NOT BE AS STRONG AS SUNDAY...BUT WILL NOT DIMINISH SUFFICIENTLY TO PRECLUDE CONTINUED BLOWING AND DRIFTING AND MAKE IT DIFFICULT FOR ROAD CREWS TO MAKE ANY HEADWAY...ASSUMING FORECAST SNOW AMOUNTS OF COURSE. THIS WOULD BE COINCIDENT WITH WIDESPREAD TEMPS IN THE SINGLE DIGITS AND TEENS BELOW ZERO...AND WIND CHILLS 25 TO 45 BELOW. WITH LITTLE CHANGE IN PATTERN INTO TUE...AND PERSISTENT NWLY WINDS...TEMPS AT MASON CITY FOR INSTANCE MAY NOT TOP ZERO UNTIL WEDNESDAY. THIS COULD RESULT IN A 30 HOUR PERIOD WITH AT LEAST MINOR BLOWING SNOW AND WARNING CRITERIA WIND CHILLS /-30F/. NEEDLESS TO SAY...THE BEGINNING OF NEXT WEEK WILL NEED CONSIDERABLE ATTENTION IN THE COMING DAYS. REMAINDER OF THE PERIOD LOOKS TO REMAIN COLD WITH CONTINUED BELOW NORMAL TEMPS. EXTENDED PATTERN LOOKS SOMEWHAT MORE INACTIVE THANKFULLY WITH ONLY PRECIP WINDOW AROUND WED NIGHT...MAINLY DUE TO ECMWF WHICH SUGGESTS A LOBE OF FORCING ACCOMPANYING YET ANOTHER COLD FRONTAL PASSAGE TO END THE WORK WEEK. && .AVIATION...24/06Z ISSUED AT 1200 AM CST THU JAN 23 2014 VFR CONDITIONS EXPECTED THROUGH THE CRITICAL TAF PERIOD. SOUTHERLY WINDS TO INCREASE THROUGH THE PERIOD...AND SHIFT AROUND TO THE SOUTHWEST TO WEST FRIDAY AND TO THE NORTHWEST FRIDAY EVENING BEFORE INCREASING FURTHER. PRECIP EXPECTED TO SPREAD SOUTHWARD ACROSS THE CWA BY LATE FRIDAY AFTERNOON INTO FRIDAY EVENING...WITH CIGS LOWERING AND MVFR VSBYS. MAINLY SNOW EXPECTED AT THE NORTHERN/EASTERN TAF SITES WITH A RAIN/SNOW MIX POSSIBLE AT KDSM AND OTM. && .DMX WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SHORT TERM...PODRAZIK LONG TERM...SMALL AVIATION...BEERENDS
AREA FORECAST DISCUSSION
NWS JACKSON KY
1259 AM EST SAT JAN 25 2014 .UPDATE... ISSUED AT 1259 AM EST SAT JAN 25 2014 UPDATED THE FORECAST TO BETTER REFLECT CURRENT CONDITIONS AND MODEL TRENDS. JUST TWEAKED THE TEMPS AND WINDS A BIT. THE FORECAST IS ON TRACK AND THE FRONT CONTINUES TO MOVE TOWARD THE AREA. THE LEADING EDGE OF THE SNOW IS OVER HAMILTON OHIO. UPDATE ISSUED AT 1005 PM EST FRI JAN 24 2014 THE 18Z GFS AND 0Z NAM HAVE A BIT HIGHER QPF FROM 12Z TO 18Z FROM JACKSON AND ESTILL COUNTIES SOUTHWEST TOWARD WAYNE COUNTY AND THEN EAST ACROSS LAUREL COUNTY TO WESTERN HARLAN COUNTY COMPARED TO THE PREVIOUS FORECAST. THE 22Z HRRR DATA IS ALSO SUPPORTIVE OF SLIGHTLY HIGHER QPF THAT PERIOD NEARER TO THE TN BORDER INCLUDING OUR SOUTHWEST COUNTIES. WITH THIS IN MIND...WE HAVE OPTED TO UP QPF IN THAT AREA FOR THE 12Z TO 18Z SATURDAY PERIOD AND THIS ALSO UPPED SNOWFALL AS WELL. AT THIS POINT...WE ALSO HAVE OPTED TO INCREASE SNOW TO LIQUID RATIOS FROM 6Z TO 18Z A BIT TO ABOUT 13:1 OR NEAR THE CLIMATOLOGICAL AVERAGE. THIS LED TO VERY MINOR CHANGES AND BRINGS AMOUNTS TO A SOLID 2 TO 3 INCHES IN MOST PLACES BY LATE SATURDAY EVENING. AT THIS POINT...THE WSW STILL LOOKS WARRANTED AND VALID TIMES ALSO LOOK GOOD. THE UPDATED SNOWFALL STILL FITS WITHIN THE EARLIER RANGES SO NO CHANGES TO THE WSW TEXT PRODUCT ARE EXPECTED. GRIDS WILL BE FRESHENED UP BASED ON THE 10 PM EST OBS AND A FRESHENED UP ZFP WILL ALSO BE SENT TO COVER THE SLIGHTLY HIGHER SNOWFALL FOR PARTS OF THE SOUTHWEST. UPDATE ISSUED AT 735 PM EST FRI JAN 24 2014 HOURLY GRIDS HAVE BEEN UPDATED FOR HOURLY TEMP...WIND AND DEWPOINT TRENDS. OVERALL...THE PREVIOUS FORECAST HAD A GOOD HANDLE ON THE UPCOMING WINTER SYSTEM THAT WILL AFFECT THE REGION LATER TONIGHT INTO SATURDAY EVENING. ALTHOUGH PW IS PROGGED TO CLIMB TO NEAR 0.4 INCHES DURING THIS EVENT... THERE ARE SOME LIMITING FACTORS TO THE SNOW TO LIQUID RATIOS FOR THIS EVENT. MODEL TIMEHEIGHT SECTIONS DO NOT HAVE A DEEP SATURATED LEVEL NEAR THE -10C LEVEL FOR A VERY SUSTAINED PERIOD AND FOR MOST OF THE EVENT OMEGA APPEARS LIMITED IN THE DENDRITIC GROWTH ZONE. THIS SHOULD LEAD TO NEAR TO SLIGHTLY ABOVE AVERAGE SNOW TO LIQUID RATIOS NEAR 13:1. AT THIS POINT...OUR QPF IS CLOSER TO THE WETTER NAM AND HIGHER THAN THE LATEST GFS AND WPC GUIDANCE. OVERALL...IT APPEARS THAT 2 TO 3 INCH AMOUNTS SHOULD BE COMMON BY SATURDAY EVENING. AMOUNTS NEARING 4 INCHES ARE POSSIBLE...BUT AT THIS POINT IT DOES NOT APPEAR THAT THEY WILL BE WIDESPREAD IN ANY PARTICULAR QUADRANT OF THE CWA. THE HIGHEST SNOWFALL SHOULD BE ACROSS THE HIGHER RIDGES NEAR THE VA BORDER AND IN THE NW PART OF THE CWA. THE 18Z MODEL DATA SUGGESTED SLIGHTLY STRONGER SUSTAINED WINDS FROM MIDDAY SATURDAY INTO SATURDAY EVENING AND GUSTS COULD REACH THE 30 TO 35 MPH RANGE AT TIMES DURING SNOW SHOWERS ON SATURDAY AFTERNOON OR EVENING. THE 18Z NAM HAS SOME QPF FROM SCATTERED SNOW SHOWERS DURING THE 0Z TO 3Z SUNDAY PERIOD OVER THE SOUTHEAST COUNTIES AND IT APPEARS THAT SUSTAINED WINDS AND GUSTS SHOULD LINGER THROUGH LATE EVENING THERE AS WELL SO BLOWING SNOW SHOULD ALSO BE A THREAT THEN AS WELL. WITH THAT IN MIND WE HAVE OPTED TO EXTEND THE ADVISORY IN TIME A COUPLE OF HOURS LONGER INTO SATURDAY EVENING OVER THE SOUTHEAST COUNTIES TO MATCH AREAS TO OUR EAST. OTHER THAN THE ADJUSTMENTS FOR TRENDS DURING THE NEXT FEW HOURS... AND GOING A BIT STRONGER WITH MIDDAY TO EARLY EVENING WINDS AND WIND GUSTS ON SATURDAY...NO OTHER CHANGES WERE MADE TO THE GRIDS. && .SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT) ISSUED AT 342 PM EST FRI JAN 24 2014 SURFACE HIGH PRESSURE WAS SPRAWLED FROM THE LOWER MISSISSIPPI VALLEY THROUGH SOUTHERN TEXAS...WITH DEEP LOW PRESSURE TRAVERSING EASTERN CANADA. A TIGHT PRESSURE GRADIENT EXISTS IN BETWEEN THE TWO SURFACE FEATURES FROM THE PLAINS THROUGH THE GREAT LAKES AND OHIO VALLEY. ALOFT...FLATTER FLOW IS NOTED ACROSS THE MID-MISSISSIPPI VALLEY...WITH ANOTHER VIGOROUS SHORT WAVE TROUGH DIGGING INTO THE NORTHERN PLAINS AND GREAT LAKES. EASTERN KENTUCKY HAS BEEN ENJOYING A MOSTLY SUNNY DAY AND DESPITE THE FRIGID START ACROSS THE AREA...TEMPERATURES HAVE MANAGED TO MAKE IT INTO THE LOWER 20S FOR MOST LOCATIONS THANKS TO SOUTH TO SOUTHWEST WINDS. THE MODELS ARE IN GOOD AGREEMENT THROUGH THE SHORT TERM...WITH THE NORTHERN STREAM SHORT WAVE TROUGH CONTINUING TO DIG ACROSS THE GREAT LAKES AND INTO THE OHIO VALLEY TONIGHT AND SATURDAY. THE COMBINATION OF A STOUT LOW LEVEL JET OF 50 TO 60 KTS AT 850 MB...A LEFT EXIT REGION OF AN UPPER LEVEL JET STREAK...AND THE MID-LEVEL TROUGH AXIS...WILL PROVIDE AMPLE FORCING FOR SOME ACCUMULATING SNOWS BEGINNING DURING THE PRE-DAWN HOURS IN THE NORTHWEST...AND THEN CLOSER TO DAWN FOR THE SOUTHEAST. 10 TO 20 MPH SOUTHWEST TO WEST WINDS...WITH GUSTS UP TO 30 MPH...WILL BLOW THE SNOW AROUND AT TIMES DURING THE DAY SATURDAY...AND ALLOW FOR QUICK REDUCTIONS IN VISIBILITY. THE BEST FORCING AND MOISTURE LINE UP DURING THE MORNING...AND THEN THE STEADY SNOW WILL BECOME MORE SHOWERY IN NATURE DURING THE AFTERNOON...WITH THE EAST AND SOUTHEAST SEEING A BRIEF WINDOW OF AN UPSLOPE COMPONENT LATER IN THE DAY. IN GENERAL...MOST LOCATIONS LOOK TO SEE 2 TO 3 INCHES...WITH A FEW SPOTS SEEING PERHAPS A BIT MORE WHERE SNOW SHOWER ACTIVITY CAN LINGER THE LONGEST. SNOW SHOWERS WILL COME TO AN END EARLY SATURDAY EVENING AS THE TROUGH DEPARTS AND THE LOW LEVELS DRY OUT. TEMPERATURES WILL LIKELY DIP DOWN INTO THE SINGLE DIGITS FOR THE EASTERN VALLEYS THROUGH AROUND MIDNIGHT TONIGHT...BEFORE THE INCREASE IN CLOUDS AND PRESSURE GRADIENT ALLOW READINGS TO CLIMB FOR THE SECOND HALF OF THE NIGHT. HIGHS ON SATURDAY WILL MAKE IT INTO THE UPPER 20S AND LOWER 30S...WITH LOWS SATURDAY NIGHT BACK DOWN INTO THE 5 TO 10 DEGREE RANGE. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 310 PM EST FRI JAN 24 2014 THE MODELS ARE IN FAIR TO AVERAGE AGREEMENT ALOFT THROUGH THE FIRST PART OF THE EXTENDED AS THEY DEPICT INTRUSIONS AND SUBSEQUENT RETREATS OF PORTIONS OF THE RESIDENT DEEP UPPER LOW OVER THE HUDSON BAY. HEIGHTS WILL BE ON AN UPSWING LOCALLY ON SUNDAY AS THE LATEST U.S. SPOKE OF THE TROUGH LIFTS QUICKLY NORTHEAST AS THE UPPER LOW ITSELF RECHARGES AND BACK-BUILDS TO THE NORTHWEST OF THE OHIO VALLEY. THE NEXT SURGE SOUTH TAKES PLACE SUNDAY NIGHT WITH A DEVELOPING NODE OF THIS CANADIAN TROUGH...THE BANE OF OUR RECENT WINTER DAYS... SPILLING INTO THE STATES. A LEAD SHORT WAVE WILL PASS NORTH OF KENTUCKY HELPING TO USHER THESE LOW HEIGHTS INTO THE OHIO VALLEY FOR MONDAY. THE GFS AND ECMWF ARE SIMILAR WITH THE TIMING AND MAGNITUDE OF THESE HEIGHT FALLS ALONG WITH THE ENERGY STREAM THAT ACCOMPANIES THEM. THE GEM...MEANWHILE...IS DISCOUNTED THROUGH THE EXTENDED AS IT HAS A BROADER UPPER LOW AND A SLOWER PROGRESSION THAN THE OTHER MODELS. ON TUESDAY...THE WESTERN MOST PORTION OF THE LATEST SWIPE FROM THE NORTHERN TROUGH WILL AMPLIFY OVER THE SOUTHERN PLAINS. THIS AMPLIFICATION WELL TO OUR SOUTHWEST IS MORE PROMINENT IN THE ECMWF THAN THE GFS THIS ROUND. WE HAVE BEEN WATCHING THIS AREA FOR THE PAST SEVERAL RUNS AS A POTENTIAL SOURCE OF A SOUTHERN LOW CAPABLE OF TAKING ADVANTAGE OF THE BAROCLINIC ZONE WITH VERY COLD AIR TO THE NORTH AND GULF MOISTURE TO THE SOUTH. THE ECMWF HAS A VERSION OF THIS BUT DOES TAKE ITS MORE AMPLIFIED WAVE THROUGH THE SOUTHEAST QUICKER AND FURTHER SOUTH THAN THE GFS. EITHER WAY BOTH MODELS KEEP THE ENERGY WITH THIS WAVE MOSTLY HARMLESSLY SOUTH OF EAST KENTUCKY. THE NEXT ITERATION IN THIS BOUT OF PERIODIC INVASIONS FROM CANADIAN TAKES PLACE ON THURSDAY NIGHT INTO FRIDAY WHEN A CLOSED LOW SINKS INTO THE GREAT LAKES...AGAIN MORE IMPRESSIVE...BUT FURTHER NORTH...IN THE ECMWF THAN THE GFS. THIS PROGGED SHALLOWER PATH OF THE UPPER LOW/S NODES LATE IN THE PERIOD SHOULD ALLOW FOR A RELAXATION OF THE BITTER COLD THROUGHOUT THE AREA...BUT THIS MAY NOT BE ENTIRELY A GOOD THING IF MOISTURE RETURNS TOO FAST AND THE SFC DOESN/T WARM AS MUCH AS IT DOES ALOFT...STAY TUNED. DID FAVOR A GENERAL MODEL BLEND THROUGH MIDWEEK BEFORE LEANING MORE TOWARD THE 12Z ECMWF INTO FRIDAY. SENSIBLE WEATHER WILL FEATURE A NOTICEABLE WARM UP FOR EAST KENTUCKY ON SUNDAY AS THE CORE OF THE COLD AIR LIFTS NORTHEAST AND OUT OF THE AREA ALONG WITH SOUTH WINDS AND PARTIAL SUNSHINE. THIS WILL BE HINDERED BY THE VERY COLD START TO THE DAY AND A FRESH SNOW PACK SO THAT MANY SHELTERED PLACES MAY NOT GET MUCH PAST FREEZING INTO THE EVENING. THIS SO CALLED WARMING WILL NOT LAST LONG...THOUGH...AS THE LOW RESPONSIBLE MOVES PAST TO THE NORTH SUNDAY NIGHT AND SENDS ANOTHER VERSION OF THE ARCTIC FRONT SOUTHEAST THROUGH KENTUCKY BY 12Z MONDAY. THIS WILL BE ACCOMPANIED BY A DECENT CHANCE OF SNOW... PROBABLY WITH LIGHT ACCUMULATIONS...AND BITTER COLD AIR POURING INTO THE STATE. THUS THE STAGE WILL BE SET FOR ANOTHER VERY COLD NIGHT AND TEMPS LIKELY DOWN NEAR OR BELOW ZERO. THE HIGH RESPONSIBLE WILL MOVE OVER THE AREA THROUGH WEDNESDAY WITH AN EVEN COLDER MORNING POSSIBLE...ESPECIALLY IF THE SOUTHERN WAVE PASSES WELL TO THE SOUTH AS IT APPEARS TO BE DOING. SOME MODERATION BEGINS ON THURSDAY AS THE HIGH SHIFTS EAST AND RETURN FLOW COMMENCES. THE NEXT COLD FRONT WOULD IMPACT THE AREA THAT NIGHT WITH SNOW SHOWERS THE MAIN THREAT BUT... FOR A CHANGE...THE COLDEST AIR SKIRTS OFF TO THE NORTHEAST THROUGH THE DAY FRIDAY. THEN BEGINS OUR THAW...BUT CAN IT TAKE HOLD? THE CR GRID LOAD CAME IN FAIRLY DECENT...BUT DID MAKE CHANGES MAINLY TO A COUPLE OF LOW TEMP GRIDS AND POPS DURING THE MIDDLE OF THE WEEK...TO REFLECT HIGH PRESSURE MORE IN CONTROL FOR CHILLIER NIGHTS AND DRIER CONDITIONS. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 1259 AM EST SAT JAN 25 2014 A FRONT IS APPROACHING THE AREA FROM THE NORTHWEST. AS IT NEARS...THE CIGS WILL GENERALLY LOWER. THE WINDS AREA ALSO INCREASING OUT AHEAD OF THE FRONT. THE WINDS WILL BE TRICKY THROUGH 9Z AS SOME OF THE TAFS MAY DECOUPLE AND THE WINDS DROP OFF FOR A WHILE AND THEN BECOME GUSTY ONCE AGAIN AS THE INVERSION BREAKS FROM THE HIGHER MOMENTUM WINDS MIXING DOWN TO THE SURFACE. THE FRONT SHOULD BE MOVING INTO THE TAF STATIONS BETWEEN 11-12Z. AS IT DOES THE CIGS WILL DROP...HOWEVER THE MOST LIMITING FACTOR WILL BE THE VSBY. THE COMBINATION OF THE BANDS OF HEAVY SNOW...ALONG WITH THE BLOWING SNOW WILL BE BRING THE VSBY DOWN TO 1 MILE OR LESS AT TIMES WITH WIND GUSTS UP TO 25-30 KTS POSSIBLE. A SECOND FRONT WILL MOVE ACROSS THE AREA AROUND 22-00Z. AS IT DOES...IT MAY BRING THE STRONGEST WIND GUSTS OF THE DAY WITH WIND GUSTS UP TO 35 KNOTS. THE CIGS AND VSBY SHOULD BEGIN TO IMPROVE TO MVFR AFTER 00Z AS THE ARCTIC AIR POURS BACK INTO THE AREA. && .JKL WATCHES/WARNINGS/ADVISORIES... WINTER WEATHER ADVISORY UNTIL 6 PM EST THIS EVENING FOR KYZ044- 050>052-059-060-104-106. WINTER WEATHER ADVISORY UNTIL 6 PM EST THIS EVENING FOR KYZ058- 068-069-079-080-083-084-108-111-114. WINTER WEATHER ADVISORY FROM 5 AM EARLY THIS MORNING TO 10 PM EST THIS EVENING FOR KYZ088-118-120. WINTER WEATHER ADVISORY UNTIL 8 PM EST THIS EVENING FOR KYZ085>087-107-109-110-112-113-115>117-119. && $$ UPDATE...JJ SHORT TERM...GEOGERIAN LONG TERM...GREIF AVIATION...JJ
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
1007 PM EST FRI JAN 24 2014 .UPDATE... ISSUED AT 1005 PM EST FRI JAN 24 2014 THE 18Z GFS AND 0Z NAM HAVE A BIT HIGHER QPF FROM 12Z TO 18Z FROM JACKSON AND ESTILL COUNTIES SOUTHWEST TOWARD WAYNE COUNTY AND THEN EAST ACROSS LAUREL COUNTY TO WESTERN HARLAN COUNTY COMPARED TO THE PREVIOUS FORECAST. THE 22Z HRRR DATA IS ALSO SUPPORTIVE OF SLIGHTLY HIGHER QPF THAT PERIOD NEARER TO THE TN BORDER INCLUDING OUR SOUTHWEST COUNTIES. WITH THIS IN MIND...WE HAVE OPTED TO UP QPF IN THAT AREA FOR THE 12Z TO 18Z SATURDAY PERIOD AND THIS ALSO UPPED SNOWFALL AS WELL. AT THIS POINT...WE ALSO HAVE OPTED TO INCREASE SNOW TO LIQUID RATIOS FROM 6Z TO 18Z A BIT TO ABOUT 13:1 OR NEAR THE CLIMATOLOGICAL AVERAGE. THIS LED TO VERY MINOR CHANGES AND BRINGS AMOUNTS TO A SOLID 2 TO 3 INCHES IN MOST PLACES BY LATE SATURDAY EVENING. AT THIS POINT...THE WSW STILL LOOKS WARRANTED AND VALID TIMES ALSO LOOK GOOD. THE UPDATED SNOWFALL STILL FITS WITHIN THE EARLIER RANGES SO NO CHANGES TO THE WSW TEXT PRODUCT ARE EXPECTED. GRIDS WILL BE FRESHENED UP BASED ON THE 10 PM EST OBS AND A FRESHENED UP ZFP WILL ALSO BE SENT TO COVER THE SLIGHTLY HIGHER SNOWFALL FOR PARTS OF THE SOUTHWEST. UPDATE ISSUED AT 735 PM EST FRI JAN 24 2014 HOURLY GRIDS HAVE BEEN UPDATED FOR HOURLY TEMP...WIND AND DEWPOINT TRENDS. OVERALL...THE PREVIOUS FORECAST HAD A GOOD HANDLE ON THE UPCOMING WINTER SYSTEM THAT WILL AFFECT THE REGION LATER TONIGHT INTO SATURDAY EVENING. ALTHOUGH PW IS PROGGED TO CLIMB TO NEAR 0.4 INCHES DURING THIS EVENT... THERE ARE SOME LIMITING FACTORS TO THE SNOW TO LIQUID RATIOS FOR THIS EVENT. MODEL TIMEHEIGHT SECTIONS DO NOT HAVE A DEEP SATURATED LEVEL NEAR THE -10C LEVEL FOR A VERY SUSTAINED PERIOD AND FOR MOST OF THE EVENT OMEGA APPEARS LIMITED IN THE DENDRITIC GROWTH ZONE. THIS SHOULD LEAD TO NEAR TO SLIGHTLY ABOVE AVERAGE SNOW TO LIQUID RATIOS NEAR 13:1. AT THIS POINT...OUR QPF IS CLOSER TO THE WETTER NAM AND HIGHER THAN THE LATEST GFS AND WPC GUIDANCE. OVERALL...IT APPEARS THAT 2 TO 3 INCH AMOUNTS SHOULD BE COMMON BY SATURDAY EVENING. AMOUNTS NEARING 4 INCHES ARE POSSIBLE...BUT AT THIS POINT IT DOES NOT APPEAR THAT THEY WILL BE WIDESPREAD IN ANY PARTICULAR QUADRANT OF THE CWA. THE HIGHEST SNOWFALL SHOULD BE ACROSS THE HIGHER RIDGES NEAR THE VA BORDER AND IN THE NW PART OF THE CWA. THE 18Z MODEL DATA SUGGESTED SLIGHTLY STRONGER SUSTAINED WINDS FROM MIDDAY SATURDAY INTO SATURDAY EVENING AND GUSTS COULD REACH THE 30 TO 35 MPH RANGE AT TIMES DURING SNOW SHOWERS ON SATURDAY AFTERNOON OR EVENING. THE 18Z NAM HAS SOME QPF FROM SCATTERED SNOW SHOWERS DURING THE 0Z TO 3Z SUNDAY PERIOD OVER THE SOUTHEAST COUNTIES AND IT APPEARS THAT SUSTAINED WINDS AND GUSTS SHOULD LINGER THROUGH LATE EVENING THERE AS WELL SO BLOWING SNOW SHOULD ALSO BE A THREAT THEN AS WELL. WITH THAT IN MIND WE HAVE OPTED TO EXTEND THE ADVISORY IN TIME A COUPLE OF HOURS LONGER INTO SATURDAY EVENING OVER THE SOUTHEAST COUNTIES TO MATCH AREAS TO OUR EAST. OTHER THAN THE ADJUSTMENTS FOR TRENDS DURING THE NEXT FEW HOURS... AND GOING A BIT STRONGER WITH MIDDAY TO EARLY EVENING WINDS AND WIND GUSTS ON SATURDAY...NO OTHER CHANGES WERE MADE TO THE GRIDS. && .SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT) ISSUED AT 342 PM EST FRI JAN 24 2014 SURFACE HIGH PRESSURE WAS SPRAWLED FROM THE LOWER MISSISSIPPI VALLEY THROUGH SOUTHERN TEXAS...WITH DEEP LOW PRESSURE TRAVERSING EASTERN CANADA. A TIGHT PRESSURE GRADIENT EXISTS IN BETWEEN THE TWO SURFACE FEATURES FROM THE PLAINS THROUGH THE GREAT LAKES AND OHIO VALLEY. ALOFT...FLATTER FLOW IS NOTED ACROSS THE MID-MISSISSIPPI VALLEY...WITH ANOTHER VIGOROUS SHORT WAVE TROUGH DIGGING INTO THE NORTHERN PLAINS AND GREAT LAKES. EASTERN KENTUCKY HAS BEEN ENJOYING A MOSTLY SUNNY DAY AND DESPITE THE FRIGID START ACROSS THE AREA...TEMPERATURES HAVE MANAGED TO MAKE IT INTO THE LOWER 20S FOR MOST LOCATIONS THANKS TO SOUTH TO SOUTHWEST WINDS. THE MODELS ARE IN GOOD AGREEMENT THROUGH THE SHORT TERM...WITH THE NORTHERN STREAM SHORT WAVE TROUGH CONTINUING TO DIG ACROSS THE GREAT LAKES AND INTO THE OHIO VALLEY TONIGHT AND SATURDAY. THE COMBINATION OF A STOUT LOW LEVEL JET OF 50 TO 60 KTS AT 850 MB...A LEFT EXIT REGION OF AN UPPER LEVEL JET STREAK...AND THE MID-LEVEL TROUGH AXIS...WILL PROVIDE AMPLE FORCING FOR SOME ACCUMULATING SNOWS BEGINNING DURING THE PRE-DAWN HOURS IN THE NORTHWEST...AND THEN CLOSER TO DAWN FOR THE SOUTHEAST. 10 TO 20 MPH SOUTHWEST TO WEST WINDS...WITH GUSTS UP TO 30 MPH...WILL BLOW THE SNOW AROUND AT TIMES DURING THE DAY SATURDAY...AND ALLOW FOR QUICK REDUCTIONS IN VISIBILITY. THE BEST FORCING AND MOISTURE LINE UP DURING THE MORNING...AND THEN THE STEADY SNOW WILL BECOME MORE SHOWERY IN NATURE DURING THE AFTERNOON...WITH THE EAST AND SOUTHEAST SEEING A BRIEF WINDOW OF AN UPSLOPE COMPONENT LATER IN THE DAY. IN GENERAL...MOST LOCATIONS LOOK TO SEE 2 TO 3 INCHES...WITH A FEW SPOTS SEEING PERHAPS A BIT MORE WHERE SNOW SHOWER ACTIVITY CAN LINGER THE LONGEST. SNOW SHOWERS WILL COME TO AN END EARLY SATURDAY EVENING AS THE TROUGH DEPARTS AND THE LOW LEVELS DRY OUT. TEMPERATURES WILL LIKELY DIP DOWN INTO THE SINGLE DIGITS FOR THE EASTERN VALLEYS THROUGH AROUND MIDNIGHT TONIGHT...BEFORE THE INCREASE IN CLOUDS AND PRESSURE GRADIENT ALLOW READINGS TO CLIMB FOR THE SECOND HALF OF THE NIGHT. HIGHS ON SATURDAY WILL MAKE IT INTO THE UPPER 20S AND LOWER 30S...WITH LOWS SATURDAY NIGHT BACK DOWN INTO THE 5 TO 10 DEGREE RANGE. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 310 PM EST FRI JAN 24 2014 THE MODELS ARE IN FAIR TO AVERAGE AGREEMENT ALOFT THROUGH THE FIRST PART OF THE EXTENDED AS THEY DEPICT INTRUSIONS AND SUBSEQUENT RETREATS OF PORTIONS OF THE RESIDENT DEEP UPPER LOW OVER THE HUDSON BAY. HEIGHTS WILL BE ON AN UPSWING LOCALLY ON SUNDAY AS THE LATEST U.S. SPOKE OF THE TROUGH LIFTS QUICKLY NORTHEAST AS THE UPPER LOW ITSELF RECHARGES AND BACK-BUILDS TO THE NORTHWEST OF THE OHIO VALLEY. THE NEXT SURGE SOUTH TAKES PLACE SUNDAY NIGHT WITH A DEVELOPING NODE OF THIS CANADIAN TROUGH...THE BANE OF OUR RECENT WINTER DAYS... SPILLING INTO THE STATES. A LEAD SHORT WAVE WILL PASS NORTH OF KENTUCKY HELPING TO USHER THESE LOW HEIGHTS INTO THE OHIO VALLEY FOR MONDAY. THE GFS AND ECMWF ARE SIMILAR WITH THE TIMING AND MAGNITUDE OF THESE HEIGHT FALLS ALONG WITH THE ENERGY STREAM THAT ACCOMPANIES THEM. THE GEM...MEANWHILE...IS DISCOUNTED THROUGH THE EXTENDED AS IT HAS A BROADER UPPER LOW AND A SLOWER PROGRESSION THAN THE OTHER MODELS. ON TUESDAY...THE WESTERN MOST PORTION OF THE LATEST SWIPE FROM THE NORTHERN TROUGH WILL AMPLIFY OVER THE SOUTHERN PLAINS. THIS AMPLIFICATION WELL TO OUR SOUTHWEST IS MORE PROMINENT IN THE ECMWF THAN THE GFS THIS ROUND. WE HAVE BEEN WATCHING THIS AREA FOR THE PAST SEVERAL RUNS AS A POTENTIAL SOURCE OF A SOUTHERN LOW CAPABLE OF TAKING ADVANTAGE OF THE BAROCLINIC ZONE WITH VERY COLD AIR TO THE NORTH AND GULF MOISTURE TO THE SOUTH. THE ECMWF HAS A VERSION OF THIS BUT DOES TAKE ITS MORE AMPLIFIED WAVE THROUGH THE SOUTHEAST QUICKER AND FURTHER SOUTH THAN THE GFS. EITHER WAY BOTH MODELS KEEP THE ENERGY WITH THIS WAVE MOSTLY HARMLESSLY SOUTH OF EAST KENTUCKY. THE NEXT ITERATION IN THIS BOUT OF PERIODIC INVASIONS FROM CANADIAN TAKES PLACE ON THURSDAY NIGHT INTO FRIDAY WHEN A CLOSED LOW SINKS INTO THE GREAT LAKES...AGAIN MORE IMPRESSIVE...BUT FURTHER NORTH...IN THE ECMWF THAN THE GFS. THIS PROGGED SHALLOWER PATH OF THE UPPER LOW/S NODES LATE IN THE PERIOD SHOULD ALLOW FOR A RELAXATION OF THE BITTER COLD THROUGHOUT THE AREA...BUT THIS MAY NOT BE ENTIRELY A GOOD THING IF MOISTURE RETURNS TOO FAST AND THE SFC DOESN/T WARM AS MUCH AS IT DOES ALOFT...STAY TUNED. DID FAVOR A GENERAL MODEL BLEND THROUGH MIDWEEK BEFORE LEANING MORE TOWARD THE 12Z ECMWF INTO FRIDAY. SENSIBLE WEATHER WILL FEATURE A NOTICEABLE WARM UP FOR EAST KENTUCKY ON SUNDAY AS THE CORE OF THE COLD AIR LIFTS NORTHEAST AND OUT OF THE AREA ALONG WITH SOUTH WINDS AND PARTIAL SUNSHINE. THIS WILL BE HINDERED BY THE VERY COLD START TO THE DAY AND A FRESH SNOW PACK SO THAT MANY SHELTERED PLACES MAY NOT GET MUCH PAST FREEZING INTO THE EVENING. THIS SO CALLED WARMING WILL NOT LAST LONG...THOUGH...AS THE LOW RESPONSIBLE MOVES PAST TO THE NORTH SUNDAY NIGHT AND SENDS ANOTHER VERSION OF THE ARCTIC FRONT SOUTHEAST THROUGH KENTUCKY BY 12Z MONDAY. THIS WILL BE ACCOMPANIED BY A DECENT CHANCE OF SNOW... PROBABLY WITH LIGHT ACCUMULATIONS...AND BITTER COLD AIR POURING INTO THE STATE. THUS THE STAGE WILL BE SET FOR ANOTHER VERY COLD NIGHT AND TEMPS LIKELY DOWN NEAR OR BELOW ZERO. THE HIGH RESPONSIBLE WILL MOVE OVER THE AREA THROUGH WEDNESDAY WITH AN EVEN COLDER MORNING POSSIBLE...ESPECIALLY IF THE SOUTHERN WAVE PASSES WELL TO THE SOUTH AS IT APPEARS TO BE DOING. SOME MODERATION BEGINS ON THURSDAY AS THE HIGH SHIFTS EAST AND RETURN FLOW COMMENCES. THE NEXT COLD FRONT WOULD IMPACT THE AREA THAT NIGHT WITH SNOW SHOWERS THE MAIN THREAT BUT... FOR A CHANGE...THE COLDEST AIR SKIRTS OFF TO THE NORTHEAST THROUGH THE DAY FRIDAY. THEN BEGINS OUR THAW...BUT CAN IT TAKE HOLD? THE CR GRID LOAD CAME IN FAIRLY DECENT...BUT DID MAKE CHANGES MAINLY TO A COUPLE OF LOW TEMP GRIDS AND POPS DURING THE MIDDLE OF THE WEEK...TO REFLECT HIGH PRESSURE MORE IN CONTROL FOR CHILLIER NIGHTS AND DRIER CONDITIONS. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING) ISSUED AT 740 PM EST FRI JAN 24 2014 CLOUDS WILL INCREASE AND LOWER...MAINLY BETWEEN 6Z AND 12Z...ALONG WITH SOUTH TO SOUTHWEST WINDS INCREASING TO AROUND 10 KTS...WITH OCCASIONAL GUSTS OVER 20 KTS BETWEEN 06 AND 12Z IN BROAD VALLEYS AND THE RIDGES...AND THEN MIXING SHOULD BRING THOSE TO ALL LOCATIONS AFTER 12Z. CEILINGS WILL LOWER TO MVFR AND THEN IFR BETWEEN 10 AND 15Z...WITH LIGHT TO OCCASIONALLY MODERATE SNOW AND BLOWING SNOW AS A STRONG UPPER LEVEL DISTURBANCE AND COLD FRONT APPROACH AND MOVE THROUGH THE AREA. VISIBILITIES COULD BE REDUCED TO LIFR OR LOWER AT TIMES DURING THE HEAVIER BURSTS OF SNOW AND WIND. && .JKL WATCHES/WARNINGS/ADVISORIES... WINTER WEATHER ADVISORY FROM 1 AM TO 6 PM EST SATURDAY FOR KYZ044-050>052-059-060-104-106. WINTER WEATHER ADVISORY FROM 3 AM TO 6 PM EST SATURDAY FOR KYZ058-068-069-079-080-083-084-108-111-114. WINTER WEATHER ADVISORY FROM 5 AM TO 10 PM EST SATURDAY FOR KYZ088-118-120. WINTER WEATHER ADVISORY FROM 3 AM TO 8 PM EST SATURDAY FOR KYZ085>087-107-109-110-112-113-115>117-119. && $$ UPDATE...JP SHORT TERM...GEOGERIAN LONG TERM...GREIF AVIATION...JP
AREA FORECAST DISCUSSION
NWS GRAY ME
817 PM EST SAT JAN 25 2014 .SYNOPSIS... A COLD FRONT WILL CROSS THE REGION THIS EVENING. A WEAK RIDGE OF HIGH PRESSURE FOLLOWS FOR SUNDAY. A WARM FRONT WILL LIFT INTO THE REGION SUNDAY NIGHT AHEAD OF LOW PRESSURE MOVING EAST OUT OF THE GREAT LAKES. LOW PRESSURE WILL MOVE EAST THROUGH SOUTHERN QUEBEC ON MONDAY DRIVING A TRAILING COLD FRONT THROUGH THE REGION. HIGH PRESSURE ATTEMPTS TO BUILD IN FROM THE SOUTH MONDAY NIGHT THROUGH THURSDAY. A COLD FRONT WILL APPROACH FROM THE WEST THURSDAY NIGHT BEFORE CROSSING THE AREA. && .NEAR TERM /THROUGH SUNDAY/... UPDATE... HAVE UPDATED GRIDS BASED ON CURRENT CONDITIONS ACROSS MAINE AND NEW HAMPSHIRE. LATEST RADAR IMAGERY CONTINUES TO SHOW AREAS OF SNOW SHOWERS AND FLURRIES MOVING RAPIDLY ACROSS THE REGION FROM SOUTHWEST TO NORTHEAST. IN NEW YORK STATE...A LONG LINE OF SNOW SHOWERS AND ISOLATED SNOW SQUALLS ASSOCIATED WITH THE ARCTIC FRONT WILL CONTINUE TO PROGRESS TO THE EAST...REACHING WESTERN NEW HAMPSHIRE AROUND 07Z. THE INTENSITY OF THIS BAND SHOULD WEAKEN GRADUALLY AS IT MOVES INTO OUR FORECAST AREA. NEVERTHELESS...AN INCH OR TWO OF SNOWFALL WILL OCCUR IN MANY AREAS OVERNIGHT. USED WIND EFFECT TOOL TO BRING SLIGHTLY MORE SNOWFALL TO THE MOUNTAINS LATE TONIGHT AS WNW FLOW DEVELOPS. ADJUSTMENTS WERE MADE TO INCREASE POPS OVER THE NEXT FEW HOURS. OTHERWISE...JUST A FEW MINOR ADJUSTMENTS TO THE FORECAST. MOST RECENT HRRR RUNS ARE NOT AVAILABLE FOR THIS PACKAGE. PREV DISC...AT 19Z...A 984 MILLIBAR LOW WAS OVER WESTERN QUEBEC WITH TRAILING COLD FRONTS THROUGH THE EASTERN GREAT LAKES. THE LOW WILL TRACK TO NEAR THE GASPE PENINSULA BY 12Z SUNDAY DRAGGING THE COLD FRONTS QUICKLY EASTWARD ACROSS THE FORECAST AREA. WE`LL SEE A FEW SNOW SHOWERS ALONG AND AHEAD OF THESE BOUNDARIES WITH THE BEST CHANCE FOR AN INCH OR TWO OF ACCUMULATION FROM THE CONNECTICUT VALLEY NORTHEASTWARD ACROSS THE HIGHER TERRAIN INTO THE MAINE MOUNTAINS AND FOOTHILLS. ANOTHER AREA WITH SEVERAL INCHES OF ACCUMULATION MAYBE JUST INLAND FROM THE MID COAST WHERE OCEAN EFFECT CONTINUES. ALONG THE IMMEDIATE MID COAST...THE STRONG SOUTH-SOUTHWEST WIND HAS PUSHED TEMPERATURES UP WELL INTO THE 30S WHERE MELTING AND THE POSSIBILITY OF A MIX WITH OR BRIEF CHANGE TO RAIN WILL LIMIT ANY ACCUMULATION. THE WIND ADVISORY REMAINS IN EFFECT UNTIL 7 PM AS FUNNELING BETWEEN THE VARIOUS PENINSULA`S MAY PRODUCE LOCALIZED GUSTS TO NEAR 50 MPH. IN THE WAKE OF THE SECOND FRONTAL PASSAGE...WE`LL SEE A FEW LINGERING CLOUDS AND UPSLOPE SNOW SHOWERS ACROSS THE MOUNTAINS FOR THE BALANCE OF THE NIGHT. && .SHORT TERM /SUNDAY NIGHT/... FAIR...BUT VERY COLD AND WINDY ON SUNDAY AS ARCTIC AIR DEEPENS ACROSS THE REGION ONCE AGAIN. HIGH TEMPERATURES WILL MAX OUT A GOOD 15 TO 20 DEGREES BELOW NORMAL...WITH AN APPRECIABLE WIND CHILL. IT`S LIKELY WE`LL SEE WIND CHILL HEADLINES POSTED FOR AT LEAST THE HIGHER TERRAIN DURING THE DAY ON SUNDAY. WINDS DROP OFF BY SUNDAY EVENING AS A WEAK RIDGE CRESTS ACROSS THE AREA. TEMPERATURES DROP OFF QUICKLY AFTER DUSK THEN SHOULD STABILIZE AS CLOUDS ARRIVE TOWARDS MIDNIGHT AHEAD OF THE NEXT DISTURBANCE...WITH LIGHT OVERRUNNING SNOWS BREAKING OUT MAINLY NORTH OF A LEBANON /KLEB/ TO PORTLAND /KPWM/ LINE IN THE PREDAWN HOURS ON MONDAY. && .LONG TERM /MONDAY THROUGH SATURDAY/... DEEPLY AMPLIFIED MEAN TROUGHING REMAINS OVER THE EASTERN CONUS WITH SHORT WAVE ENERGY USHERING IN REINFORCING COLD AIR EVERY 24-36 HOURS OVER THE NORTHEAST. THE NEXT IN A SERIES OF LOW PRESSURE SYSTEMS WILL MOVE OUT OF THE GREAT LAKES REGION SUNDAY NIGHT INTO MONDAY. THIS WILL TRIGGER SCATTERED WARM ADVECTION SHOWERS OVER THE REGION. MOISTURE RETURN ISN`T GOOD AND ISENTROPIC LIFT IS NOT SIGNIFICANT WITH THIS SYSTEM AS ANOTHER QUICK MOVING COLD FRONT SHUTS PRECIPITATION OFF RELATIVELY QUICKLY. STORM TOTAL SNOW AMOUNTS WILL BE NEAR 1-3 INCHES WITH HIGHER AMOUNTS ACROSS THE FAR NORTH AND OVER THE MIDCOAST. DENSE POLAR HIGH PRESSURE SPILLS INTO THE CENTRAL CONUS MONDAY AND ATTEMPTS TO BUILD INTO NEW ENGLAND. IT SUCCEEDS IN HOLDING OFF THE NEXT SPOKE OF UPPER LEVEL ENERGY UNTIL THE THURSDAY/FRIDAY TIME FRAME...WHEN ANOTHER COLD FRONT MOVES THROUGH. BY THIS TIME THE UPPER LEVEL PATTERN WILL HAVE MODERATED SOMEWHAT AND UPPER LEVEL TRAJECTORIES SHOW THE COLDEST AIR WITH THIS SYSTEM REMAINS OVER CENTRAL CANADA...WITH THE ZERO DEGREE SURFACE ISOTHERM JUST NORTH OF THE BORDER. AFTER A WARM UP INTO THE 20S AND 30S MONDAY...TEMPERATURES DROP OFF ONCE AGAIN THROUGH WEDNESDAY WITH LOWS FROM NEAR ZERO TO -10 DEGREES F AND HIGHS IN THE SINGLE DIGITS NORTH TO UPPER TEENS/20S SOUTH. A SW/W WIND CONTRIBUTES TOWARDS A GRADUAL WARM UP TOWARDS THE END OF THE WEEK WITH HIGHS IN THE 20S AND 30S BEFORE THE NEXT FROPA. && .AVIATION /01Z SUNDAY THROUGH THURSDAY/... SHORT TERM /THROUGH SUNDAY NIGHT/...AREAS OF MVFR IN SNOW SHOWERS TONIGHT WITH WND GUSTS TO 25 KT. VFR SUNDAY WITH SFC WND GUSTS TO 25 KT. AREAS OF MVFR DEVELOPING AFT 06Z MON IN LIGHT SNOW. LONG TERM...AREAS OF LIFR/IFR/MVFR BECOMING VFR MONDAY BY NOON AS SHOWERS MOVE EAST. ADDITIONAL STRATUS/FOG POSSIBLE FOR THE IMMEDIATE COAST AND IN THE MOUNTAINS FOR LATE NIGHT/EARLY MORNING PERIODS TUESDAY THROUGH THURSDAY WITH TRAPPED LOW LEVEL MOISTURE. WESTERLY WINDS MAY BE GUSTY MONDAY AND AGAIN TUESDAY. && .MARINE... SHORT TERM /THROUGH SUNDAY NIGHT/...GALES FOR ALL WATERS INTO THIS EVENING FOR GUSTS UP TO 45 KT. A BREAK IN THE GALES IS EXPECTED FOR A TIME TONIGHT BEFORE THEY REDEVELOP BEHIND AN ARCTIC FRONT EARLY SUNDAY. WE SHOULD SEE MODERATE FREEZING SPRAY RETURN DURING THE DAY ON SUNDAY AS WELL...HENCE A FREEZING SPRAY ADVISORY HAS BEEN ISSUED. LONG TERM...ON MONDAY AND TUESDAY...WINDS SHOULD BE BORDERLINE SMALL CRAFT ADVISORY LEVELS...HOWEVER WAVES WILL REMAIN ABOVE 5 FT AS A COLD FRONT CROSSES THE WATERS. SEAS CALM DOWN SOMEWHAT FOR THE MIDWEEK PERIOD BEFORE INCREASING AGAIN THURSDAY/FRIDAY. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...WIND CHILL ADVISORY FROM 5 AM TO 4 PM EST SUNDAY FOR MEZ007>009. NH...WIND CHILL ADVISORY FROM 5 AM TO 4 PM EST SUNDAY FOR NHZ001- 002. MARINE...FREEZING SPRAY ADVISORY FROM 5 AM TO 5 PM EST SUNDAY FOR ANZ150>154. GALE WARNING UNTIL 4 PM EST SUNDAY FOR ANZ150>154. && $$ JC
AREA FORECAST DISCUSSION
NWS GRAY ME
444 PM EST SAT JAN 25 2014 .SYNOPSIS... A COLD FRONT WILL CROSS THE REGION THIS EVENING. A WEAK RIDGE OF HIGH PRESSURE FOLLOWS FOR SUNDAY. A WARM FRONT WILL LIFT INTO THE REGION SUNDAY NIGHT AHEAD OF LOW PRESSURE MOVING EAST OUT OF THE GREAT LAKES. LOW PRESSURE WILL MOVE EAST THROUGH SOUTHERN QUEBEC ON MONDAY DRIVING A TRAILING COLD FRONT THROUGH THE REGION. HIGH PRESSURE ATTEMPTS TO BUILD IN FROM THE SOUTH MONDAY NIGHT THROUGH THURSDAY. A COLD FRONT WILL APPROACH FROM THE WEST THURSDAY NIGHT BEFORE CROSSING THE AREA. && .NEAR TERM /UNTIL 6 AM SUNDAY MORNING/... UPDATE... HAVE UPDATED GRIDS BASED ON CURRENT CONDITIONS ACROSS MAINE AND NEW HAMPSHIRE. LATEST RADAR IMAGERY CONTINUES TO SHOW BANDS OF SNOW SHOWERS AND FLURRIES MOVING RAPIDLY ACROSS THE REGION FROM SOUTHWEST TO NORTHEAST. HRRR RUN FROM 21Z SHOWING SOME HEAVIER SNOW SHOWER ACTIVITY ENTERING WESTERN NEW ENGLAND DURING THE NIGHT. THESE SNOW SHOWERS WILL NEED TO BE MONITORED AS THE ARCTIC FRONT MOVES THROUGH. PREV DISC... AT 19Z...A 984 MILLIBAR LOW WAS OVER WESTERN QUEBEC WITH TRAILING COLD FRONTS THROUGH THE EASTERN GREAT LAKES. THE LOW WILL TRACK TO NEAR THE GASPE PENINSULA BY 12Z SUNDAY DRAGGING THE COLD FRONTS QUICKLY EASTWARD ACROSS THE FORECAST AREA. WE`LL SEE A FEW SNOW SHOWERS ALONG AND AHEAD OF THESE BOUNDARIES WITH THE BEST CHANCE FOR AN INCH OR TWO OF ACCUMULATION FROM THE CONNECTICUT VALLEY NORTHEASTWARD ACROSS THE HIGHER TERRAIN INTO THE MAINE MOUNTAINS AND FOOTHILLS. ANOTHER AREA WITH SEVERAL INCHES OF ACCUMULATION MAYBE JUST INLAND FROM THE MID COAST WHERE OCEAN EFFECT CONTINUES. ALONG THE IMMEDIATE MID COAST...THE STRONG SOUTH-SOUTHWEST WIND HAS PUSHED TEMPERATURES UP WELL INTO THE 30S WHERE MELTING AND THE POSSIBILITY OF A MIX WITH OR BRIEF CHANGE TO RAIN WILL LIMIT ANY ACCUMULATION. THE WIND ADVISORY REMAINS IN EFFECT UNTIL 7 PM AS FUNNELING BETWEEN THE VARIOUS PENINSULA`S MAY PRODUCE LOCALIZED GUSTS TO NEAR 50 MPH. IN THE WAKE OF THE SECOND FRONTAL PASSAGE...WE`LL SEE A FEW LINGERING CLOUDS AND UPSLOPE SNOW SHOWERS ACROSS THE MOUNTAINS FOR THE BALANCE OF THE NIGHT. && .SHORT TERM /6 AM SUNDAY MORNING THROUGH SUNDAY NIGHT/... FAIR...BUT VERY COLD AND WINDY ON SUNDAY AS ARCTIC AIR DEEPENS ACROSS THE REGION ONCE AGAIN. HIGH TEMPERATURES WILL MAX OUT A GOOD 15 TO 20 DEGREES BELOW NORMAL...WITH AN APPRECIABLE WIND CHILL. IT`S LIKELY WE`LL SEE WIND CHILL HEADLINES POSTED FOR AT LEAST THE HIGHER TERRAIN DURING THE DAY ON SUNDAY. WINDS DROP OFF BY SUNDAY EVENING AS A WEAK RIDGE CRESTS ACROSS THE AREA. TEMPERATURES DROP OFF QUICKLY AFTER DUSK THEN SHOULD STABILIZE AS CLOUDS ARRIVE TOWARDS MIDNIGHT AHEAD OF THE NEXT DISTURBANCE...WITH LIGHT OVERRUNNING SNOWS BREAKING OUT MAINLY NORTH OF A LEBANON /KLEB/ TO PORTLAND /KPWM/ LINE IN THE PREDAWN HOURS ON MONDAY. && .LONG TERM /MONDAY THROUGH SATURDAY/... DEEPLY AMPLIFIED MEAN TROUGHING REMAINS OVER THE EASTERN CONUS WITH SHORT WAVE ENERGY USHERING IN REINFORCING COLD AIR EVERY 24-36 HOURS OVER THE NORTHEAST. THE NEXT IN A SERIES OF LOW PRESSURE SYSTEMS WILL MOVE OUT OF THE GREAT LAKES REGION SUNDAY NIGHT INTO MONDAY. THIS WILL TRIGGER SCATTERED WARM ADVECTION SHOWERS OVER THE REGION. MOISTURE RETURN ISN`T GOOD AND ISENTROPIC LIFT IS NOT SIGNIFICANT WITH THIS SYSTEM AS ANOTHER QUICK MOVING COLD FRONT SHUTS PRECIPITATION OFF RELATIVELY QUICKLY. STORM TOTAL SNOW AMOUNTS WILL BE NEAR 1-3 INCHES WITH HIGHER AMOUNTS ACROSS THE FAR NORTH AND OVER THE MIDCOAST. DENSE POLAR HIGH PRESSURE SPILLS INTO THE CENTRAL CONUS MONDAY AND ATTEMPTS TO BUILD INTO NEW ENGLAND. IT SUCCEEDS IN HOLDING OFF THE NEXT SPOKE OF UPPER LEVEL ENERGY UNTIL THE THURSDAY/FRIDAY TIME FRAME...WHEN ANOTHER COLD FRONT MOVES THROUGH. BY THIS TIME THE UPPER LEVEL PATTERN WILL HAVE MODERATED SOMEWHAT AND UPPER LEVEL TRAJECTORIES SHOW THE COLDEST AIR WITH THIS SYSTEM REMAINS OVER CENTRAL CANADA...WITH THE ZERO DEGREE SURFACE ISOTHERM JUST NORTH OF THE BORDER. AFTER A WARM UP INTO THE 20S AND 30S MONDAY...TEMPERATURES DROP OFF ONCE AGAIN THROUGH WEDNESDAY WITH LOWS FROM NEAR ZERO TO -10 DEGREES F AND HIGHS IN THE SINGLE DIGITS NORTH TO UPPER TEENS/20S SOUTH. A SW/W WIND CONTRIBUTES TOWARDS A GRADUAL WARM UP TOWARDS THE END OF THE WEEK WITH HIGHS IN THE 20S AND 30S BEFORE THE NEXT FROPA. && .AVIATION /22Z SATURDAY THROUGH THURSDAY/... SHORT TERM /THROUGH SUNDAY NIGHT/...AREAS OF MVFR IN SNOW SHOWERS TONIGHT WITH WND GUSTS TO 25 KT. VFR SUNDAY WITH SFC WND GUSTS TO 25 KT. AREAS OF MVFR DEVELOPING AFT 06Z MON IN LIGHT SNOW. LONG TERM...AREAS OF LIFR/IFR/MVFR BECOMING VFR MONDAY BY NOON AS SHOWERS MOVE EAST. ADDITIONAL STRATUS/FOG POSSIBLE FOR THE IMMEDIATE COAST AND IN THE MOUNTAINS FOR LATE NIGHT/EARLY MORNING PERIODS TUESDAY THROUGH THURSDAY WITH TRAPPED LOW LEVEL MOISTURE. WESTERLY WINDS MAY BE GUSTY MONDAY AND AGAIN TUESDAY. && .MARINE... SHORT TERM /THROUGH SUNDAY NIGHT/...GALE EXTENDED THROUGH 21Z SUNDAY WITH THE NEW MARINE PACKAGE THIS AFTERNOON. GALES FOR ALL WATERS INTO THIS EVENING FOR GUSTS UP TO 45 KT. A BREAK IN THE GALES IS EXPECTED FOR A TIME TONIGHT BEFORE THEY REDEVELOP BEHIND AN ARCTIC FRONT EARLY SUNDAY. WE SHOULD SEE MODERATE FREEZING SPRAY RETURN DURING THE DAY ON SUNDAY AS WELL. LONG TERM...ON MONDAY AND TUESDAY...WINDS SHOULD BE BORDERLINE SMALL CRAFT ADVISORY LEVELS...HOWEVER WAVES WILL REMAIN ABOVE 5 FT AS A COLD FRONT CROSSES THE WATERS. SEAS CALM DOWN SOMEWHAT FOR THE MIDWEEK PERIOD BEFORE INCREASING AGAIN THURSDAY/FRIDAY. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...WIND ADVISORY UNTIL 7 PM EST THIS EVENING FOR MEZ022-025>028. NH...NONE. MARINE...GALE WARNING UNTIL 4 PM EST SUNDAY FOR ANZ150>154. && $$
AREA FORECAST DISCUSSION
NWS GAYLORD MI
101 PM EST SAT JAN 25 2014 .SYNOPSIS... ISSUED AT 300 AM EST SAT JAN 25 2014 AN ALBERTA CLIPPER SYSTEM AND ARCTIC FRONT WILL CONTINUE TO ROLL THROUGH THE REGION THIS MORNING...BRINGING LAKE ENHANCED SNOW THROUGH TONIGHT. GUSTY SOUTHWEST WINDS WILL SHIFT TO THE NORTHWEST THIS MORNING...LEADING TO MORE BLOWING AND DRIFTING SNOW. ANOTHER CLIPPER SYSTEM WILL BRING ANOTHER ROUND OF ACCUMULATING SNOW FOR SUNDAY. BITTERLY COLD TEMPERATURES WILL CONTINUE THROUGH THE WEEKEND AND INTO EARLY NEXT WEEK. TEMPERATURES WILL GRADUALLY MODERATE LATE NEXT WEEK. && .UPDATE... ISSUED AT 1059 AM EST SAT JAN 25 2014 HAVE DECIDED TO EXTEND ADVISORY FOR A FEW COUNTIES THROUGH THE AFTERNOON...INCLUDING MACKINAC COUNTY AND SOME OF THE NORTHWEST LOWER COUNTIES. NOT A TON OF SNOW EXPECTED THIS AFTERNOON (2-4 INCHES WESTERN MACKINAC...1-3 INCHES CENTERED AROUND ANTRIM/KALKASKA COUNTIES NORTHWEST LOWER)...BUT STILL BLOWING AROUND A BIT SO EXTENDING THE HEADLINE IS THE PATH OF LEAST REGRET (AND AMATEUR SECOND-GUESSING) AT THIS POINT. UPDATE ISSUED AT 1011 AM EST SAT JAN 25 2014 ARCTIC COLD FRONT CROSSING SOUTHEAST LOWER MICHIGAN AT THIS TIME...WITH NORTHWEST FLOW LAKE INDUCED SNOW SHOWERS SPREADING INTO PARTS OF EASTERN UPPER/MOST OF NORTHWEST LOWER. ICE COVER WEST OF THE STRAITS HAVING AN IMPACT WITH A STRIPE OF SUNNY SKIES ACROSS THE TIP OF THE MITT AND EXTENDING TOWARD THUNDER BAY. SO HAVE ADJUSTED FORECAST TO MIDDAY TO ACCOUNT FOR AREAS WHERE IT IS NOT SNOWING. BEST SNOW SHOWERS FOCUSED TOWARD GRAND MARAIS WHERE STRONG LOW LEVEL FRONTOGENESIS ALONG LAKE INDUCED THERMAL RIDGE MAXIMIZING CONVERGENCE...THIS BAND IS CONNECTING TO BEST SNOW BANDS OVER LAKE MICHIGAN BETWEEN THE MANITOU ISLANDS AND BEAVER ISLAND...WHICH IS IMPACTING THE GRAND TRAVERSE BAY VICINITY. WILL BE EVALUATING CURRENT HEADLINES OVER THE NEXT HOUR...WHICH ARE SCHEDULED TO EXPIRE AT 16Z. UPDATE ISSUED AT 635 AM EST SAT JAN 25 2014 WIDESPREAD SYNOPTIC SNOW EVENT CONTINUES TO EVOLVE INTO A GUSTY NW FLOW LAKE EFFECT SNOW EVENT IN THE WAKE OF A STRONG COLD FRONT THAT IS CURRENTLY EXITING EAST OUT OUR CWA. NW WINDS GUSTING TO 15 KTS ARE PUSHING LAKE SNOW SHOWERS FURTHER INLAND INTO N CENTRAL AND EVEN PORTIONS OF NE LWR MICHIGAN ATTM. EXPECT COVERAGE OF SNOW SHOWERS WILL GRADUALLY ORGANIZE INTO MORE OF A TRUE NW FLOW PATTERN...IMPACTING MAINLY WRN CHIPPEWA AND MACKINAC COUNTIES WHERE OPEN UPSTREAM LAKE SUPERIOR WATER WILL RESULT IN DOWNSTREAM LAKE SNOW PRODUCTION...AND IMPACTING MAINLY NW AND N CENTRAL LWR MICHIGAN ALONG AND WEST OF I-75. THESE AREAS WILL SEE ANOTHER INCH OR TWO OF NEW SNOW TODAY...WITH GUSTY NW WINDS CONTINUING TO CAUSE SIGNIFICANT BLOWING AND DRIFTING SNOW, WILL KEEP ALL WINTER WX ADVISORIES IN EFFECT THRU THE MORNING. CAA HAS COMMENCED BEHIND THE COLD FRONT. OVERNIGHT TEMPS IN THE 20S HAVE DROPPED INTO THE TEENS...AND EXPECT TEMPS WILL CONTINUE TO DROP THROUGHOUT THE DAY. NW WINDS GUSTING TO 25 KTS COMBINED WITH TEMPS PLUMMETING INTO THE SINGLE DIGITS TODAY...WIND CHILLS WILL FALL TO AROUND -20. STAY WARM FOLKS! && .SHORT TERM...(TODAY THROUGH TONIGHT) ISSUED AT 300 AM EST SAT JAN 25 2014 ANOTHER FORECAST...AND ANOTHER ROUND OF HIGH IMPACT WEATHER CONDITIONS. SYSTEM RESPONSIBLE FOR YESTERDAYS DOWNRIGHT DANGEROUS WEATHER STILL IMPACTING OUR AREA...WITH ARCTIC FRONT MAKING STEADY SOUTHEAST PROGRESS ACROSS NORTHERN LOWER MICHIGAN. WINDS STILL A`BLOWING...BUT NOTHING EVEN REMOTELY CLOSE TO THOSE OBSERVED YESTERDAY. WIDESPREAD MAINLY LIGHT SNOW CONTINUES AHEAD OF THIS FRONT...WITH CORE OF MID LEVEL UPWARD QG SUPPORT ASSISTING FRONTAL DRIVEN CONVERGENCE TO DRIVE SUCH. LAKE PROCESSES REALLY STARTING TO RAMP UP ON LAKE SUPERIOR...AS NOTED BY KMQT AND MONTREAL RIVER RADARS AS WELL AS IR SATELLITE IMAGERY. DEEP MID LEVEL GYRE DRIVING ALL THE ABOVE ROTATING ON THE SOUTH SHORE OF HUDSON BAY...WITH DEEP NORTHWEST FLOW ON ITS BACKSIDE DIVING RIGHT FROM THE ARCTIC INTO THE NORTHERN LAKES. LATEST HIGH RES RAP GUIDANCE SHOWS NEGATIVE 20C H8 AIR ALREADY DIGGING ACROSS LAKE SUPERIOR...WITH SIMPLY NOTHING TO STOP AS IT SETS ITS SIGHTS ON THE REST OF THE AREA THROUGH THIS MORNING. FORECAST CHALLENGES THROUGH THE SHORT TERM FALL OUT OF THE ABOVE...WITH HIGHER IMPACT TEMPERATURE TRENDS AND LAKE INDUCED SNOW ACCUMULATIONS THE MAIN PRIORITY. SYNOPTIC SNOWS GIVE WAY TO MORE MESOSCALE LAKE DRIVEN PROCESSES HEADING THROUGH TODAY AS ARCTIC FRONT SLIPS STAGE RIGHT BY SUNRISE. INTENSE CAA CONTINUES TO INCREASE OVER-WATER INSTABILITY AS H8 TEMPERATURES FALL THROUGH THE NEGATIVE MIDDLE 20S CELSIUS. NORTHWEST FLOW ESSENTIALLY LOCKED IN THROUGH THE DAY...WITH DECENT MOISTURE PROFILES AND INVERSION LEVELS UP THROUGH H7 SUPPORTING GOOD LAKE CONTRIBUTION. CONDITIONS OFF LAKE SUPERIOR LOOK QUITE INTERESTING INDEED...WITH NARROWING OF OPEN WATER CHANNEL OVER THE CENTER PART OF THE LAKE RESULTING IN ENHANCED LOW LEVEL CONVERGENCE AXIS. TRENDS SUPPORT THIS ENHANCED BAND SETTING UP EARLY THIS MORNING... ESPECIALLY TARGETING LUCE COUNTY...PERHAPS CLIPPING FAR WESTERN MACKINAC AND CHIPPEWA COUNTIES. LOSS OF DGZ FAVORS LOW SNOW/LIQUID RATIOS...HELPING KEEP AMOUNTS IN CHECK. WILL TENTATIVELY HAVE A FEW INCHES OF SNOW IN FAVORED AREAS...TAPERING AMOUNTS QUICKLY AS ONE HEADS EAST. FOCUSED CONVERGENCE FROM LAKE SUPERIOR BAND LOOKS TO SPILL SOUTH INTO NORTHWEST LOWER...ALTHOUGH EXTENSIVE NORTHERN LAKE MICHIGAN ICE COVER WILL TAKE ITS TOLL ON SNOWFALL INTENSITY. OTHERWISE...TYPICAL MULTI-BANDED SNOW SHOWERS WILL IMPACT FAVORED AREAS OF NORTHWEST LOWER...WITH COLD TEMPERATURE PROFILES (THAT SMALL NON-FLUFF PRODUCING FLAKE THING) OFFSETTING GOOD THERMODYNAMICS. CAN SEE A FEW INCHES AT MOST WHERE BANDS REMAIN MOST PERSISTENT. DEEP MIXED LAYER WILL CONTINUE TO TAP INTO RELATIVELY STRONG WINDS JUST OFF THE DECK...CONTINUING THE GUSTY WINDS ACROSS THE REGION. BLOWING/DRIFTING SNOW WILL RESULT...WITH PERIODS OF REDUCED VISIBILITIES...ESPECIALLY IN OPEN AREAS. TEMPERATURES WILL TREND DOWN FROM EARLY MORNING READINGS IN THE SINGLE DIGITS AND TEENS...WITH READINGS AT LEAST A FEW DEGREES BELOW ZERO FOR NORTHEAST EAST UPPER MICHIGAN BY LATER THIS AFTERNOON. WIND CHILL VALUES WILL RUN IN THE TEENS BELOW ZERO...PUSHING THE NEGATIVE LOWER 20S LATER THIS AFTERNOON. ANOTHER HARSH WINTER DAY INDEED! AS FOR HEADLINES: SNOW AMOUNTS/WIND CHILL VALUES DEFINITELY DO NOT JUSTIFY AN EXTENSION OF CURRENT HEADLINES INTO TODAY. THAT SAID...HIGH IMPACT EVENT YESTERDAY/OVERNIGHT RESULTING IN CONTINUATION OF SNOW-COVERED ROADS...WITH SOME LIKELY NEARLY IMPASSABLE IN EXPOSED AREAS. FALLING PIXIE DUST SNOWS WILL ONLY ADD TO THE LOW VISIBILITY PRODUCED BY BLOWING/DRIFTING SNOW ALREADY ON THE GROUND. DON`T WANT TO GIVE THE IMPRESSION ALL IS CLEAR BY DROPPING THE HEADLINE...ESPECIALLY IN THE HARDER HIT AREAS ALONG AND WEST OF INTERSTATE 75. FOR SIMPLICITY...WILL EXTEND THE ADVISORY (DOWNGRADING THOSE IN WARNING) THROUGH THIS MORNING. EASTWARD DISPLACED LAKE SUPERIOR CONVERGENCE BAND AND/OR BETTER THAN ANTICIPATED LAKE SNOWS OVER NORTHWEST LOWER MAY RESULT IN FURTHER EXTENSIONS BY THE DAY CREW. TONIGHT...LAKE SNOWS CONTINUE...ALBEIT AT A LIGHTER INTENSITY GIVEN LOSS OF SYNOPTIC MOISTURE AND FALLING INVERSION HEIGHTS. MAY SEE SOME LINGERING BETTER SNOWS ACROSS EASTERN UPPER UNDER REMNANT CONVERGENCE AXIS THIS EVENING...BUT EVEN THESE SHOULD NOT ADD UP TO TOO MUCH. EVEN WITH PLENTY OF CLOUDS AND SOME LIGHT WINDS... TEMPERATURES BY MORNING EXPECTED TO DROP WELL BELOW ZERO AWAY FROM LAKE MICHIGAN. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 300 AM EST SAT JAN 25 2014 SUNDAY AND MONDAY...OUR NEXT LOW PRESSURE SYSTEM QUICKLY ENTERS THE WRN GREAT LAKES REGION EARLY SUNDAY AS THE SURFACE RIDGE AXIS PUSHES EAST OF MICHIGAN. MOIST ISENTROPIC ASCENT (I280) WILL DEVELOP FROM SW TO NE ACROSS OUR CWA SUNDAY MORNING AS WAA PATTERN SETS UP AHEAD OF THE SURFACE LOW...WITH ISENTROPIC LIFT PERSISTING THRU THE AFTERNOON. SURFACE LOW CENTER WILL TRACK THRU LOWER MICHIGAN SUNDAY EVENING...PUSHING EAST OF MICHIGAN LATE SUNDAY NIGHT. WIDESPREAD SNOW WILL DEVELOP FROM SW TO NE SUNDAY RIGHT IN LINE WITH THE ISENTROPIC ASCENT PATTERN. APPEARS THAT VIRTUALLY ALL OF OUR CWA WILL SEE SOME SNOWFALL FROM THIS SYSTEM...AND HAVE INCREASED POPS TO CATEGORICAL EVERYWHERE FOR SUNDAY AFTERNOON AND EVENING. OVERALL SYNOPTIC SNOWFALL WILL BE A GENERAL 2 TO 4 INCHES ACROSS OUR ENTIRE CWA FOR SUNDAY AND SUNDAY NIGHT. N/NW LOW LEVEL FLOW ON THE BACKSIDE OF THE LOW CENTER WILL TARGET OUR SW CWA ALONG AND WEST OF US-131 FOR LAKE ENHANCED SNOW SHOWERS SUNDAY NIGHT...WHICH SHOULD BOOST SNOWFALL TOTALS TO 4 TO 6 INCHES FOR SUNDAY AND SUNDAY NIGHT. SURFACE LOW WILL CONTINUE TO EXIT EASTWARD AWAY FROM MICHIGAN ON MONDAY. SYNOPTIC SNOW WILL COME TO AN END BY 12Z MONDAY... TRANSITIONING TO PRIMARILY A W/NW FLOW LAKE EFFECT REGIME. CATEGORICAL SNOWFALL WILL CONTINUE MONDAY AND MONDAY NIGHT FOR THE TYPICAL SNOWBELT AREAS...NAMELY NW CHIPPEWA COUNTY AND NW LWR MICHIGAN WEST OF I-75. HOWEVER...THE BIG STORY WILL BE THE FRIGID TEMPS. HIGH TEMPS MONDAY AFTERNOON WILL STRUGGLE TO WARM INTO THE SINGLE DIGITS ABOVE ZERO...AND SOME PLACES MAY VERY WELL NOT WARM INTO POSITIVE NUMBERS. THIS COLD AIRMASS WILL NOT SUPPORT LARGE FLAKE GROWTH...SO ADDITIONAL SNOW AMOUNTS FOR MONDAY AND MONDAY NIGHT WILL BE RELATIVELY MINOR (I.E. UP TO 2 INCHES FOR THE ENTIRE 24 HOUR PERIOD). TUESDAY THRU FRIDAY...WESTERLY FLOW LAKE EFFECT SNOW SHOWERS WILL CONTINUE INTO TUESDAY AS A WAVE SWINGS THRU NRN MICHIGAN ALONG THE BASE OF THE 500 MB TROUGH...PROVIDING SOME SYNOPTIC ENHANCEMENT TO ONGOING LAKE EFFECT EVENT. NARROW/FLATTENING UPPER RIDGE AXIS WILL QUICKLY PASS THRU MICHIGAN ON WEDNESDAY...WITH LOW LEVEL FLOW BACKING TO THE SW IMMEDIATELY BEHIND IT. LATEST ECMWF SUGGESTS A SLIGHT CHANGE IN THE OVERALL UPPER LEVEL PATTERN FOR THE LAST HALF OF THE WEEK AS DEEP UPPER TROUGHING SLIDES EAST AND IS GENERALLY REPLACED WITH A MORE ZONAL FLOW. THERE WILL BE ONE GLANCING BLOW FROM AN UPPER TROUGH ON THURSDAY AS A COLD FRONT SWEEPS THRU MICHIGAN. OTHERWISE...FOR WEDNESDAY...SW FLOW AHEAD OF THAT COLD FRONT WILL BOOST AFTERNOON TEMPS INTO THE TEENS...WHILE REDIRECTING FOCUS OF LAKE EFFECT SNOW SHOWERS TO THE STRAITS AND THE LAKE MICHIGAN SHORELINE COUNTIES. OUR ENTIRE CWA WILL SEE A GOOD CHANCE OF SNOW ON THURSDAY ALONG AND AHEAD OF THE COLD FRONT. AGAIN...THE COLD AIR BEHIND THIS FRONT WILL BE A GLANCING BLOW AS LOW LEVEL FLOW QUICKLY SHIFTS BACK TO THE SW ON FRIDAY. OVER-LAKE INSTABILITY WILL QUICKLY WANE ON FRIDAY AS 850 MB TEMPS WARM TO -10 TO -12 C... PRODUCING VERY MARGINAL INSTABILITY AND THUS VERY SMALL CHANCES OF SNOW. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 100 PM EST SAT JAN 25 2014 SNOW SHOWERS TO CONTINUE INTO THIS EVENING...WITH PREVAILING MVFR CONDITIONS AT PLN/TVC/MBL WITH PERIODS OF IFR IN HEAVIER SNOW SQUALLS. && .MARINE... ISSUED AT 300 AM EST SAT JAN 25 2014 STRONG CAA WILL LEAD TO GALE PRODUCING NORTHWEST WIND GUSTS ACROSS LAKE MICHIGAN TODAY. WINDS SUBSIDE SOME TONIGHT...ALTHOUGH SCA CONDITIONS ARE EXPECTED. WINDS BACK AND BECOME LIGHT SOUTHWEST SUNDAY MORNING AHEAD OF AN APPROACHING CLIPPER SYSTEM. && .APX WATCHES/WARNINGS/ADVISORIES... MI...WINTER WEATHER ADVISORY UNTIL 5 PM EST THIS AFTERNOON FOR MIZ015- 019>021-026>028-033. LH...NONE. LM...GALE WARNING UNTIL 5 PM EST THIS AFTERNOON FOR LMZ344>346. LS...NONE. && $$ UPDATE...JPB SYNOPSIS...MR SHORT TERM...MB LONG TERM...MR MARINE...MB
AREA FORECAST DISCUSSION
NWS GAYLORD MI
1103 AM EST SAT JAN 25 2014 .SYNOPSIS... ISSUED AT 300 AM EST SAT JAN 25 2014 AN ALBERTA CLIPPER SYSTEM AND ARCTIC FRONT WILL CONTINUE TO ROLL THROUGH THE REGION THIS MORNING...BRINGING LAKE ENHANCED SNOW THROUGH TONIGHT. GUSTY SOUTHWEST WINDS WILL SHIFT TO THE NORTHWEST THIS MORNING...LEADING TO MORE BLOWING AND DRIFTING SNOW. ANOTHER CLIPPER SYSTEM WILL BRING ANOTHER ROUND OF ACCUMULATING SNOW FOR SUNDAY. BITTERLY COLD TEMPERATURES WILL CONTINUE THROUGH THE WEEKEND AND INTO EARLY NEXT WEEK. TEMPERATURES WILL GRADUALLY MODERATE LATE NEXT WEEK. && .UPDATE... ISSUED AT 1059 AM EST SAT JAN 25 2014 HAVE DECIDED TO EXTEND ADVISORY FOR A FEW COUNTIES THROUGH THE AFTERNOON...INCLUDING MACKINAC COUNTY AND SOME OF THE NORTHWEST LOWER COUNTIES. NOT A TON OF SNOW EXPECTED THIS AFTERNOON (2-4 INCHES WESTERN MACKINAC...1-3 INCHES CENTERED AROUND ANTRIM/KALKASKA COUNTIES NORTHWEST LOWER)...BUT STILL BLOWING AROUND A BIT SO EXTENDING THE HEADLINE IS THE PATH OF LEAST REGRET (AND AMATEUR SECOND-GUESSING) AT THIS POINT. UPDATE ISSUED AT 1011 AM EST SAT JAN 25 2014 ARCTIC COLD FRONT CROSSING SOUTHEAST LOWER MICHIGAN AT THIS TIME...WITH NORTHWEST FLOW LAKE INDUCED SNOW SHOWERS SPREADING INTO PARTS OF EASTERN UPPER/MOST OF NORTHWEST LOWER. ICE COVER WEST OF THE STRAITS HAVING AN IMPACT WITH A STRIPE OF SUNNY SKIES ACROSS THE TIP OF THE MITT AND EXTENDING TOWARD THUNDER BAY. SO HAVE ADJUSTED FORECAST TO MIDDAY TO ACCOUNT FOR AREAS WHERE IT IS NOT SNOWING. BEST SNOW SHOWERS FOCUSED TOWARD GRAND MARAIS WHERE STRONG LOW LEVEL FRONTOGENESIS ALONG LAKE INDUCED THERMAL RIDGE MAXIMIZING CONVERGENCE...THIS BAND IS CONNECTING TO BEST SNOW BANDS OVER LAKE MICHIGAN BETWEEN THE MANITOU ISLANDS AND BEAVER ISLAND...WHICH IS IMPACTING THE GRAND TRAVERSE BAY VICINITY. WILL BE EVALUATING CURRENT HEADLINES OVER THE NEXT HOUR...WHICH ARE SCHEDULED TO EXPIRE AT 16Z. UPDATE ISSUED AT 635 AM EST SAT JAN 25 2014 WIDESPREAD SYNOPTIC SNOW EVENT CONTINUES TO EVOLVE INTO A GUSTY NW FLOW LAKE EFFECT SNOW EVENT IN THE WAKE OF A STRONG COLD FRONT THAT IS CURRENTLY EXITING EAST OUT OUR CWA. NW WINDS GUSTING TO 15 KTS ARE PUSHING LAKE SNOW SHOWERS FURTHER INLAND INTO N CENTRAL AND EVEN PORTIONS OF NE LWR MICHIGAN ATTM. EXPECT COVERAGE OF SNOW SHOWERS WILL GRADUALLY ORGANIZE INTO MORE OF A TRUE NW FLOW PATTERN...IMPACTING MAINLY WRN CHIPPEWA AND MACKINAC COUNTIES WHERE OPEN UPSTREAM LAKE SUPERIOR WATER WILL RESULT IN DOWNSTREAM LAKE SNOW PRODUCTION...AND IMPACTING MAINLY NW AND N CENTRAL LWR MICHIGAN ALONG AND WEST OF I-75. THESE AREAS WILL SEE ANOTHER INCH OR TWO OF NEW SNOW TODAY...WITH GUSTY NW WINDS CONTINUING TO CAUSE SIGNIFICANT BLOWING AND DRIFTING SNOW, WILL KEEP ALL WINTER WX ADVISORIES IN EFFECT THRU THE MORNING. CAA HAS COMMENCED BEHIND THE COLD FRONT. OVERNIGHT TEMPS IN THE 20S HAVE DROPPED INTO THE TEENS...AND EXPECT TEMPS WILL CONTINUE TO DROP THROUGHOUT THE DAY. NW WINDS GUSTING TO 25 KTS COMBINED WITH TEMPS PLUMMETING INTO THE SINGLE DIGITS TODAY...WIND CHILLS WILL FALL TO AROUND -20. STAY WARM FOLKS! && .SHORT TERM...(TODAY THROUGH TONIGHT) ISSUED AT 300 AM EST SAT JAN 25 2014 ANOTHER FORECAST...AND ANOTHER ROUND OF HIGH IMPACT WEATHER CONDITIONS. SYSTEM RESPONSIBLE FOR YESTERDAYS DOWNRIGHT DANGEROUS WEATHER STILL IMPACTING OUR AREA...WITH ARCTIC FRONT MAKING STEADY SOUTHEAST PROGRESS ACROSS NORTHERN LOWER MICHIGAN. WINDS STILL A`BLOWING...BUT NOTHING EVEN REMOTELY CLOSE TO THOSE OBSERVED YESTERDAY. WIDESPREAD MAINLY LIGHT SNOW CONTINUES AHEAD OF THIS FRONT...WITH CORE OF MID LEVEL UPWARD QG SUPPORT ASSISTING FRONTAL DRIVEN CONVERGENCE TO DRIVE SUCH. LAKE PROCESSES REALLY STARTING TO RAMP UP ON LAKE SUPERIOR...AS NOTED BY KMQT AND MONTREAL RIVER RADARS AS WELL AS IR SATELLITE IMAGERY. DEEP MID LEVEL GYRE DRIVING ALL THE ABOVE ROTATING ON THE SOUTH SHORE OF HUDSON BAY...WITH DEEP NORTHWEST FLOW ON ITS BACKSIDE DIVING RIGHT FROM THE ARCTIC INTO THE NORTHERN LAKES. LATEST HIGH RES RAP GUIDANCE SHOWS NEGATIVE 20C H8 AIR ALREADY DIGGING ACROSS LAKE SUPERIOR...WITH SIMPLY NOTHING TO STOP AS IT SETS ITS SIGHTS ON THE REST OF THE AREA THROUGH THIS MORNING. FORECAST CHALLENGES THROUGH THE SHORT TERM FALL OUT OF THE ABOVE...WITH HIGHER IMPACT TEMPERATURE TRENDS AND LAKE INDUCED SNOW ACCUMULATIONS THE MAIN PRIORITY. SYNOPTIC SNOWS GIVE WAY TO MORE MESOSCALE LAKE DRIVEN PROCESSES HEADING THROUGH TODAY AS ARCTIC FRONT SLIPS STAGE RIGHT BY SUNRISE. INTENSE CAA CONTINUES TO INCREASE OVER-WATER INSTABILITY AS H8 TEMPERATURES FALL THROUGH THE NEGATIVE MIDDLE 20S CELSIUS. NORTHWEST FLOW ESSENTIALLY LOCKED IN THROUGH THE DAY...WITH DECENT MOISTURE PROFILES AND INVERSION LEVELS UP THROUGH H7 SUPPORTING GOOD LAKE CONTRIBUTION. CONDITIONS OFF LAKE SUPERIOR LOOK QUITE INTERESTING INDEED...WITH NARROWING OF OPEN WATER CHANNEL OVER THE CENTER PART OF THE LAKE RESULTING IN ENHANCED LOW LEVEL CONVERGENCE AXIS. TRENDS SUPPORT THIS ENHANCED BAND SETTING UP EARLY THIS MORNING... ESPECIALLY TARGETING LUCE COUNTY...PERHAPS CLIPPING FAR WESTERN MACKINAC AND CHIPPEWA COUNTIES. LOSS OF DGZ FAVORS LOW SNOW/LIQUID RATIOS...HELPING KEEP AMOUNTS IN CHECK. WILL TENTATIVELY HAVE A FEW INCHES OF SNOW IN FAVORED AREAS...TAPERING AMOUNTS QUICKLY AS ONE HEADS EAST. FOCUSED CONVERGENCE FROM LAKE SUPERIOR BAND LOOKS TO SPILL SOUTH INTO NORTHWEST LOWER...ALTHOUGH EXTENSIVE NORTHERN LAKE MICHIGAN ICE COVER WILL TAKE ITS TOLL ON SNOWFALL INTENSITY. OTHERWISE...TYPICAL MULTI-BANDED SNOW SHOWERS WILL IMPACT FAVORED AREAS OF NORTHWEST LOWER...WITH COLD TEMPERATURE PROFILES (THAT SMALL NON-FLUFF PRODUCING FLAKE THING) OFFSETTING GOOD THERMODYNAMICS. CAN SEE A FEW INCHES AT MOST WHERE BANDS REMAIN MOST PERSISTENT. DEEP MIXED LAYER WILL CONTINUE TO TAP INTO RELATIVELY STRONG WINDS JUST OFF THE DECK...CONTINUING THE GUSTY WINDS ACROSS THE REGION. BLOWING/DRIFTING SNOW WILL RESULT...WITH PERIODS OF REDUCED VISIBILITIES...ESPECIALLY IN OPEN AREAS. TEMPERATURES WILL TREND DOWN FROM EARLY MORNING READINGS IN THE SINGLE DIGITS AND TEENS...WITH READINGS AT LEAST A FEW DEGREES BELOW ZERO FOR NORTHEAST EAST UPPER MICHIGAN BY LATER THIS AFTERNOON. WIND CHILL VALUES WILL RUN IN THE TEENS BELOW ZERO...PUSHING THE NEGATIVE LOWER 20S LATER THIS AFTERNOON. ANOTHER HARSH WINTER DAY INDEED! AS FOR HEADLINES: SNOW AMOUNTS/WIND CHILL VALUES DEFINITELY DO NOT JUSTIFY AN EXTENSION OF CURRENT HEADLINES INTO TODAY. THAT SAID...HIGH IMPACT EVENT YESTERDAY/OVERNIGHT RESULTING IN CONTINUATION OF SNOW-COVERED ROADS...WITH SOME LIKELY NEARLY IMPASSABLE IN EXPOSED AREAS. FALLING PIXIE DUST SNOWS WILL ONLY ADD TO THE LOW VISIBILITY PRODUCED BY BLOWING/DRIFTING SNOW ALREADY ON THE GROUND. DON`T WANT TO GIVE THE IMPRESSION ALL IS CLEAR BY DROPPING THE HEADLINE...ESPECIALLY IN THE HARDER HIT AREAS ALONG AND WEST OF INTERSTATE 75. FOR SIMPLICITY...WILL EXTEND THE ADVISORY (DOWNGRADING THOSE IN WARNING) THROUGH THIS MORNING. EASTWARD DISPLACED LAKE SUPERIOR CONVERGENCE BAND AND/OR BETTER THAN ANTICIPATED LAKE SNOWS OVER NORTHWEST LOWER MAY RESULT IN FURTHER EXTENSIONS BY THE DAY CREW. TONIGHT...LAKE SNOWS CONTINUE...ALBEIT AT A LIGHTER INTENSITY GIVEN LOSS OF SYNOPTIC MOISTURE AND FALLING INVERSION HEIGHTS. MAY SEE SOME LINGERING BETTER SNOWS ACROSS EASTERN UPPER UNDER REMNANT CONVERGENCE AXIS THIS EVENING...BUT EVEN THESE SHOULD NOT ADD UP TO TOO MUCH. EVEN WITH PLENTY OF CLOUDS AND SOME LIGHT WINDS... TEMPERATURES BY MORNING EXPECTED TO DROP WELL BELOW ZERO AWAY FROM LAKE MICHIGAN. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 300 AM EST SAT JAN 25 2014 SUNDAY AND MONDAY...OUR NEXT LOW PRESSURE SYSTEM QUICKLY ENTERS THE WRN GREAT LAKES REGION EARLY SUNDAY AS THE SURFACE RIDGE AXIS PUSHES EAST OF MICHIGAN. MOIST ISENTROPIC ASCENT (I280) WILL DEVELOP FROM SW TO NE ACROSS OUR CWA SUNDAY MORNING AS WAA PATTERN SETS UP AHEAD OF THE SURFACE LOW...WITH ISENTROPIC LIFT PERSISTING THRU THE AFTERNOON. SURFACE LOW CENTER WILL TRACK THRU LOWER MICHIGAN SUNDAY EVENING...PUSHING EAST OF MICHIGAN LATE SUNDAY NIGHT. WIDESPREAD SNOW WILL DEVELOP FROM SW TO NE SUNDAY RIGHT IN LINE WITH THE ISENTROPIC ASCENT PATTERN. APPEARS THAT VIRTUALLY ALL OF OUR CWA WILL SEE SOME SNOWFALL FROM THIS SYSTEM...AND HAVE INCREASED POPS TO CATEGORICAL EVERYWHERE FOR SUNDAY AFTERNOON AND EVENING. OVERALL SYNOPTIC SNOWFALL WILL BE A GENERAL 2 TO 4 INCHES ACROSS OUR ENTIRE CWA FOR SUNDAY AND SUNDAY NIGHT. N/NW LOW LEVEL FLOW ON THE BACKSIDE OF THE LOW CENTER WILL TARGET OUR SW CWA ALONG AND WEST OF US-131 FOR LAKE ENHANCED SNOW SHOWERS SUNDAY NIGHT...WHICH SHOULD BOOST SNOWFALL TOTALS TO 4 TO 6 INCHES FOR SUNDAY AND SUNDAY NIGHT. SURFACE LOW WILL CONTINUE TO EXIT EASTWARD AWAY FROM MICHIGAN ON MONDAY. SYNOPTIC SNOW WILL COME TO AN END BY 12Z MONDAY... TRANSITIONING TO PRIMARILY A W/NW FLOW LAKE EFFECT REGIME. CATEGORICAL SNOWFALL WILL CONTINUE MONDAY AND MONDAY NIGHT FOR THE TYPICAL SNOWBELT AREAS...NAMELY NW CHIPPEWA COUNTY AND NW LWR MICHIGAN WEST OF I-75. HOWEVER...THE BIG STORY WILL BE THE FRIGID TEMPS. HIGH TEMPS MONDAY AFTERNOON WILL STRUGGLE TO WARM INTO THE SINGLE DIGITS ABOVE ZERO...AND SOME PLACES MAY VERY WELL NOT WARM INTO POSITIVE NUMBERS. THIS COLD AIRMASS WILL NOT SUPPORT LARGE FLAKE GROWTH...SO ADDITIONAL SNOW AMOUNTS FOR MONDAY AND MONDAY NIGHT WILL BE RELATIVELY MINOR (I.E. UP TO 2 INCHES FOR THE ENTIRE 24 HOUR PERIOD). TUESDAY THRU FRIDAY...WESTERLY FLOW LAKE EFFECT SNOW SHOWERS WILL CONTINUE INTO TUESDAY AS A WAVE SWINGS THRU NRN MICHIGAN ALONG THE BASE OF THE 500 MB TROUGH...PROVIDING SOME SYNOPTIC ENHANCEMENT TO ONGOING LAKE EFFECT EVENT. NARROW/FLATTENING UPPER RIDGE AXIS WILL QUICKLY PASS THRU MICHIGAN ON WEDNESDAY...WITH LOW LEVEL FLOW BACKING TO THE SW IMMEDIATELY BEHIND IT. LATEST ECMWF SUGGESTS A SLIGHT CHANGE IN THE OVERALL UPPER LEVEL PATTERN FOR THE LAST HALF OF THE WEEK AS DEEP UPPER TROUGHING SLIDES EAST AND IS GENERALLY REPLACED WITH A MORE ZONAL FLOW. THERE WILL BE ONE GLANCING BLOW FROM AN UPPER TROUGH ON THURSDAY AS A COLD FRONT SWEEPS THRU MICHIGAN. OTHERWISE...FOR WEDNESDAY...SW FLOW AHEAD OF THAT COLD FRONT WILL BOOST AFTERNOON TEMPS INTO THE TEENS...WHILE REDIRECTING FOCUS OF LAKE EFFECT SNOW SHOWERS TO THE STRAITS AND THE LAKE MICHIGAN SHORELINE COUNTIES. OUR ENTIRE CWA WILL SEE A GOOD CHANCE OF SNOW ON THURSDAY ALONG AND AHEAD OF THE COLD FRONT. AGAIN...THE COLD AIR BEHIND THIS FRONT WILL BE A GLANCING BLOW AS LOW LEVEL FLOW QUICKLY SHIFTS BACK TO THE SW ON FRIDAY. OVER-LAKE INSTABILITY WILL QUICKLY WANE ON FRIDAY AS 850 MB TEMPS WARM TO -10 TO -12 C... PRODUCING VERY MARGINAL INSTABILITY AND THUS VERY SMALL CHANCES OF SNOW. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 635 AM EST SAT JAN 25 2014 LAKE EFFECT SNOW SHOWERS AND NW WINDS GUSTING TO 25 KTS WILL CONTINUE TO IMPACT ALL NRN LWR MICHIGAN TAF SITES TODAY AND TONIGHT...FREQUENTLY DROPPING CONDITIONS TO MVFR/IFR WITHIN THESE SNOW SHOWERS. SNOW SHOWERS WILL MAINLY IMPACT NW LWR MICHIGAN TAF SITES TONIGHT AS NW WINDS DIMINISH TO 10 TO 15 KTS AND SHIFT TO THE WEST. && .MARINE... ISSUED AT 300 AM EST SAT JAN 25 2014 STRONG CAA WILL LEAD TO GALE PRODUCING NORTHWEST WIND GUSTS ACROSS LAKE MICHIGAN TODAY. WINDS SUBSIDE SOME TONIGHT...ALTHOUGH SCA CONDITIONS ARE EXPECTED. WINDS BACK AND BECOME LIGHT SOUTHWEST SUNDAY MORNING AHEAD OF AN APPROACHING CLIPPER SYSTEM. && .APX WATCHES/WARNINGS/ADVISORIES... MI...WINTER WEATHER ADVISORY UNTIL 5 PM EST THIS AFTERNOON FOR MIZ015- 019>021-026>028-033. LH...NONE. LM...GALE WARNING UNTIL 5 PM EST THIS AFTERNOON FOR LMZ344>346. LS...NONE. && $$ UPDATE...JPB SYNOPSIS...MR SHORT TERM...MB LONG TERM...MR AVIATION...MR MARINE...MB
AREA FORECAST DISCUSSION
NWS GAYLORD MI
1011 AM EST SAT JAN 25 2014 .SYNOPSIS... ISSUED AT 300 AM EST SAT JAN 25 2014 AN ALBERTA CLIPPER SYSTEM AND ARCTIC FRONT WILL CONTINUE TO ROLL THROUGH THE REGION THIS MORNING...BRINGING LAKE ENHANCED SNOW THROUGH TONIGHT. GUSTY SOUTHWEST WINDS WILL SHIFT TO THE NORTHWEST THIS MORNING...LEADING TO MORE BLOWING AND DRIFTING SNOW. ANOTHER CLIPPER SYSTEM WILL BRING ANOTHER ROUND OF ACCUMULATING SNOW FOR SUNDAY. BITTERLY COLD TEMPERATURES WILL CONTINUE THROUGH THE WEEKEND AND INTO EARLY NEXT WEEK. TEMPERATURES WILL GRADUALLY MODERATE LATE NEXT WEEK. && .UPDATE... ISSUED AT 1011 AM EST SAT JAN 25 2014 ARCTIC COLD FRONT CROSSING SOUTHEAST LOWER MICHIGAN AT THIS TIME...WITH NORTHWEST FLOW LAKE INDUCED SNOW SHOWERS SPREADING INTO PARTS OF EASTERN UPPER/MOST OF NORTHWEST LOWER. ICE COVER WEST OF THE STRAITS HAVING AN IMPACT WITH A STRIPE OF SUNNY SKIES ACROSS THE TIP OF THE MITT AND EXTENDING TOWARD THUNDER BAY. SO HAVE ADJUSTED FORECAST TO MIDDAY TO ACCOUNT FOR AREAS WHERE IT IS NOT SNOWING. BEST SNOW SHOWERS FOCUSED TOWARD GRAND MARAIS WHERE STRONG LOW LEVEL FRONTOGENESIS ALONG LAKE INDUCED THERMAL RIDGE MAXIMIZING CONVERGENCE...THIS BAND IS CONNECTING TO BEST SNOW BANDS OVER LAKE MICHIGAN BETWEEN THE MANITOU ISLANDS AND BEAVER ISLAND...WHICH IS IMPACTING THE GRAND TRAVERSE BAY VICINITY. WILL BE EVALUATING CURRENT HEADLINES OVER THE NEXT HOUR...WHICH ARE SCHEDULED TO EXPIRE AT 16Z. UPDATE ISSUED AT 635 AM EST SAT JAN 25 2014 WIDESPREAD SYNOPTIC SNOW EVENT CONTINUES TO EVOLVE INTO A GUSTY NW FLOW LAKE EFFECT SNOW EVENT IN THE WAKE OF A STRONG COLD FRONT THAT IS CURRENTLY EXITING EAST OUT OUR CWA. NW WINDS GUSTING TO 15 KTS ARE PUSHING LAKE SNOW SHOWERS FURTHER INLAND INTO N CENTRAL AND EVEN PORTIONS OF NE LWR MICHIGAN ATTM. EXPECT COVERAGE OF SNOW SHOWERS WILL GRADUALLY ORGANIZE INTO MORE OF A TRUE NW FLOW PATTERN...IMPACTING MAINLY WRN CHIPPEWA AND MACKINAC COUNTIES WHERE OPEN UPSTREAM LAKE SUPERIOR WATER WILL RESULT IN DOWNSTREAM LAKE SNOW PRODUCTION...AND IMPACTING MAINLY NW AND N CENTRAL LWR MICHIGAN ALONG AND WEST OF I-75. THESE AREAS WILL SEE ANOTHER INCH OR TWO OF NEW SNOW TODAY...WITH GUSTY NW WINDS CONTINUING TO CAUSE SIGNIFICANT BLOWING AND DRIFTING SNOW, WILL KEEP ALL WINTER WX ADVISORIES IN EFFECT THRU THE MORNING. CAA HAS COMMENCED BEHIND THE COLD FRONT. OVERNIGHT TEMPS IN THE 20S HAVE DROPPED INTO THE TEENS...AND EXPECT TEMPS WILL CONTINUE TO DROP THROUGHOUT THE DAY. NW WINDS GUSTING TO 25 KTS COMBINED WITH TEMPS PLUMMETING INTO THE SINGLE DIGITS TODAY...WIND CHILLS WILL FALL TO AROUND -20. STAY WARM FOLKS! && .SHORT TERM...(TODAY THROUGH TONIGHT) ISSUED AT 300 AM EST SAT JAN 25 2014 ANOTHER FORECAST...AND ANOTHER ROUND OF HIGH IMPACT WEATHER CONDITIONS. SYSTEM RESPONSIBLE FOR YESTERDAYS DOWNRIGHT DANGEROUS WEATHER STILL IMPACTING OUR AREA...WITH ARCTIC FRONT MAKING STEADY SOUTHEAST PROGRESS ACROSS NORTHERN LOWER MICHIGAN. WINDS STILL A`BLOWING...BUT NOTHING EVEN REMOTELY CLOSE TO THOSE OBSERVED YESTERDAY. WIDESPREAD MAINLY LIGHT SNOW CONTINUES AHEAD OF THIS FRONT...WITH CORE OF MID LEVEL UPWARD QG SUPPORT ASSISTING FRONTAL DRIVEN CONVERGENCE TO DRIVE SUCH. LAKE PROCESSES REALLY STARTING TO RAMP UP ON LAKE SUPERIOR...AS NOTED BY KMQT AND MONTREAL RIVER RADARS AS WELL AS IR SATELLITE IMAGERY. DEEP MID LEVEL GYRE DRIVING ALL THE ABOVE ROTATING ON THE SOUTH SHORE OF HUDSON BAY...WITH DEEP NORTHWEST FLOW ON ITS BACKSIDE DIVING RIGHT FROM THE ARCTIC INTO THE NORTHERN LAKES. LATEST HIGH RES RAP GUIDANCE SHOWS NEGATIVE 20C H8 AIR ALREADY DIGGING ACROSS LAKE SUPERIOR...WITH SIMPLY NOTHING TO STOP AS IT SETS ITS SIGHTS ON THE REST OF THE AREA THROUGH THIS MORNING. FORECAST CHALLENGES THROUGH THE SHORT TERM FALL OUT OF THE ABOVE...WITH HIGHER IMPACT TEMPERATURE TRENDS AND LAKE INDUCED SNOW ACCUMULATIONS THE MAIN PRIORITY. SYNOPTIC SNOWS GIVE WAY TO MORE MESOSCALE LAKE DRIVEN PROCESSES HEADING THROUGH TODAY AS ARCTIC FRONT SLIPS STAGE RIGHT BY SUNRISE. INTENSE CAA CONTINUES TO INCREASE OVER-WATER INSTABILITY AS H8 TEMPERATURES FALL THROUGH THE NEGATIVE MIDDLE 20S CELSIUS. NORTHWEST FLOW ESSENTIALLY LOCKED IN THROUGH THE DAY...WITH DECENT MOISTURE PROFILES AND INVERSION LEVELS UP THROUGH H7 SUPPORTING GOOD LAKE CONTRIBUTION. CONDITIONS OFF LAKE SUPERIOR LOOK QUITE INTERESTING INDEED...WITH NARROWING OF OPEN WATER CHANNEL OVER THE CENTER PART OF THE LAKE RESULTING IN ENHANCED LOW LEVEL CONVERGENCE AXIS. TRENDS SUPPORT THIS ENHANCED BAND SETTING UP EARLY THIS MORNING... ESPECIALLY TARGETING LUCE COUNTY...PERHAPS CLIPPING FAR WESTERN MACKINAC AND CHIPPEWA COUNTIES. LOSS OF DGZ FAVORS LOW SNOW/LIQUID RATIOS...HELPING KEEP AMOUNTS IN CHECK. WILL TENTATIVELY HAVE A FEW INCHES OF SNOW IN FAVORED AREAS...TAPERING AMOUNTS QUICKLY AS ONE HEADS EAST. FOCUSED CONVERGENCE FROM LAKE SUPERIOR BAND LOOKS TO SPILL SOUTH INTO NORTHWEST LOWER...ALTHOUGH EXTENSIVE NORTHERN LAKE MICHIGAN ICE COVER WILL TAKE ITS TOLL ON SNOWFALL INTENSITY. OTHERWISE...TYPICAL MULTI-BANDED SNOW SHOWERS WILL IMPACT FAVORED AREAS OF NORTHWEST LOWER...WITH COLD TEMPERATURE PROFILES (THAT SMALL NON-FLUFF PRODUCING FLAKE THING) OFFSETTING GOOD THERMODYNAMICS. CAN SEE A FEW INCHES AT MOST WHERE BANDS REMAIN MOST PERSISTENT. DEEP MIXED LAYER WILL CONTINUE TO TAP INTO RELATIVELY STRONG WINDS JUST OFF THE DECK...CONTINUING THE GUSTY WINDS ACROSS THE REGION. BLOWING/DRIFTING SNOW WILL RESULT...WITH PERIODS OF REDUCED VISIBILITIES...ESPECIALLY IN OPEN AREAS. TEMPERATURES WILL TREND DOWN FROM EARLY MORNING READINGS IN THE SINGLE DIGITS AND TEENS...WITH READINGS AT LEAST A FEW DEGREES BELOW ZERO FOR NORTHEAST EAST UPPER MICHIGAN BY LATER THIS AFTERNOON. WIND CHILL VALUES WILL RUN IN THE TEENS BELOW ZERO...PUSHING THE NEGATIVE LOWER 20S LATER THIS AFTERNOON. ANOTHER HARSH WINTER DAY INDEED! AS FOR HEADLINES: SNOW AMOUNTS/WIND CHILL VALUES DEFINITELY DO NOT JUSTIFY AN EXTENSION OF CURRENT HEADLINES INTO TODAY. THAT SAID...HIGH IMPACT EVENT YESTERDAY/OVERNIGHT RESULTING IN CONTINUATION OF SNOW-COVERED ROADS...WITH SOME LIKELY NEARLY IMPASSABLE IN EXPOSED AREAS. FALLING PIXIE DUST SNOWS WILL ONLY ADD TO THE LOW VISIBILITY PRODUCED BY BLOWING/DRIFTING SNOW ALREADY ON THE GROUND. DON`T WANT TO GIVE THE IMPRESSION ALL IS CLEAR BY DROPPING THE HEADLINE...ESPECIALLY IN THE HARDER HIT AREAS ALONG AND WEST OF INTERSTATE 75. FOR SIMPLICITY...WILL EXTEND THE ADVISORY (DOWNGRADING THOSE IN WARNING) THROUGH THIS MORNING. EASTWARD DISPLACED LAKE SUPERIOR CONVERGENCE BAND AND/OR BETTER THAN ANTICIPATED LAKE SNOWS OVER NORTHWEST LOWER MAY RESULT IN FURTHER EXTENSIONS BY THE DAY CREW. TONIGHT...LAKE SNOWS CONTINUE...ALBEIT AT A LIGHTER INTENSITY GIVEN LOSS OF SYNOPTIC MOISTURE AND FALLING INVERSION HEIGHTS. MAY SEE SOME LINGERING BETTER SNOWS ACROSS EASTERN UPPER UNDER REMNANT CONVERGENCE AXIS THIS EVENING...BUT EVEN THESE SHOULD NOT ADD UP TO TOO MUCH. EVEN WITH PLENTY OF CLOUDS AND SOME LIGHT WINDS... TEMPERATURES BY MORNING EXPECTED TO DROP WELL BELOW ZERO AWAY FROM LAKE MICHIGAN. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 300 AM EST SAT JAN 25 2014 SUNDAY AND MONDAY...OUR NEXT LOW PRESSURE SYSTEM QUICKLY ENTERS THE WRN GREAT LAKES REGION EARLY SUNDAY AS THE SURFACE RIDGE AXIS PUSHES EAST OF MICHIGAN. MOIST ISENTROPIC ASCENT (I280) WILL DEVELOP FROM SW TO NE ACROSS OUR CWA SUNDAY MORNING AS WAA PATTERN SETS UP AHEAD OF THE SURFACE LOW...WITH ISENTROPIC LIFT PERSISTING THRU THE AFTERNOON. SURFACE LOW CENTER WILL TRACK THRU LOWER MICHIGAN SUNDAY EVENING...PUSHING EAST OF MICHIGAN LATE SUNDAY NIGHT. WIDESPREAD SNOW WILL DEVELOP FROM SW TO NE SUNDAY RIGHT IN LINE WITH THE ISENTROPIC ASCENT PATTERN. APPEARS THAT VIRTUALLY ALL OF OUR CWA WILL SEE SOME SNOWFALL FROM THIS SYSTEM...AND HAVE INCREASED POPS TO CATEGORICAL EVERYWHERE FOR SUNDAY AFTERNOON AND EVENING. OVERALL SYNOPTIC SNOWFALL WILL BE A GENERAL 2 TO 4 INCHES ACROSS OUR ENTIRE CWA FOR SUNDAY AND SUNDAY NIGHT. N/NW LOW LEVEL FLOW ON THE BACKSIDE OF THE LOW CENTER WILL TARGET OUR SW CWA ALONG AND WEST OF US-131 FOR LAKE ENHANCED SNOW SHOWERS SUNDAY NIGHT...WHICH SHOULD BOOST SNOWFALL TOTALS TO 4 TO 6 INCHES FOR SUNDAY AND SUNDAY NIGHT. SURFACE LOW WILL CONTINUE TO EXIT EASTWARD AWAY FROM MICHIGAN ON MONDAY. SYNOPTIC SNOW WILL COME TO AN END BY 12Z MONDAY... TRANSITIONING TO PRIMARILY A W/NW FLOW LAKE EFFECT REGIME. CATEGORICAL SNOWFALL WILL CONTINUE MONDAY AND MONDAY NIGHT FOR THE TYPICAL SNOWBELT AREAS...NAMELY NW CHIPPEWA COUNTY AND NW LWR MICHIGAN WEST OF I-75. HOWEVER...THE BIG STORY WILL BE THE FRIGID TEMPS. HIGH TEMPS MONDAY AFTERNOON WILL STRUGGLE TO WARM INTO THE SINGLE DIGITS ABOVE ZERO...AND SOME PLACES MAY VERY WELL NOT WARM INTO POSITIVE NUMBERS. THIS COLD AIRMASS WILL NOT SUPPORT LARGE FLAKE GROWTH...SO ADDITIONAL SNOW AMOUNTS FOR MONDAY AND MONDAY NIGHT WILL BE RELATIVELY MINOR (I.E. UP TO 2 INCHES FOR THE ENTIRE 24 HOUR PERIOD). TUESDAY THRU FRIDAY...WESTERLY FLOW LAKE EFFECT SNOW SHOWERS WILL CONTINUE INTO TUESDAY AS A WAVE SWINGS THRU NRN MICHIGAN ALONG THE BASE OF THE 500 MB TROUGH...PROVIDING SOME SYNOPTIC ENHANCEMENT TO ONGOING LAKE EFFECT EVENT. NARROW/FLATTENING UPPER RIDGE AXIS WILL QUICKLY PASS THRU MICHIGAN ON WEDNESDAY...WITH LOW LEVEL FLOW BACKING TO THE SW IMMEDIATELY BEHIND IT. LATEST ECMWF SUGGESTS A SLIGHT CHANGE IN THE OVERALL UPPER LEVEL PATTERN FOR THE LAST HALF OF THE WEEK AS DEEP UPPER TROUGHING SLIDES EAST AND IS GENERALLY REPLACED WITH A MORE ZONAL FLOW. THERE WILL BE ONE GLANCING BLOW FROM AN UPPER TROUGH ON THURSDAY AS A COLD FRONT SWEEPS THRU MICHIGAN. OTHERWISE...FOR WEDNESDAY...SW FLOW AHEAD OF THAT COLD FRONT WILL BOOST AFTERNOON TEMPS INTO THE TEENS...WHILE REDIRECTING FOCUS OF LAKE EFFECT SNOW SHOWERS TO THE STRAITS AND THE LAKE MICHIGAN SHORELINE COUNTIES. OUR ENTIRE CWA WILL SEE A GOOD CHANCE OF SNOW ON THURSDAY ALONG AND AHEAD OF THE COLD FRONT. AGAIN...THE COLD AIR BEHIND THIS FRONT WILL BE A GLANCING BLOW AS LOW LEVEL FLOW QUICKLY SHIFTS BACK TO THE SW ON FRIDAY. OVER-LAKE INSTABILITY WILL QUICKLY WANE ON FRIDAY AS 850 MB TEMPS WARM TO -10 TO -12 C... PRODUCING VERY MARGINAL INSTABILITY AND THUS VERY SMALL CHANCES OF SNOW. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 635 AM EST SAT JAN 25 2014 LAKE EFFECT SNOW SHOWERS AND NW WINDS GUSTING TO 25 KTS WILL CONTINUE TO IMPACT ALL NRN LWR MICHIGAN TAF SITES TODAY AND TONIGHT...FREQUENTLY DROPPING CONDITIONS TO MVFR/IFR WITHIN THESE SNOW SHOWERS. SNOW SHOWERS WILL MAINLY IMPACT NW LWR MICHIGAN TAF SITES TONIGHT AS NW WINDS DIMINISH TO 10 TO 15 KTS AND SHIFT TO THE WEST. && .MARINE... ISSUED AT 300 AM EST SAT JAN 25 2014 STRONG CAA WILL LEAD TO GALE PRODUCING NORTHWEST WIND GUSTS ACROSS LAKE MICHIGAN TODAY. WINDS SUBSIDE SOME TONIGHT...ALTHOUGH SCA CONDITIONS ARE EXPECTED. WINDS BACK AND BECOME LIGHT SOUTHWEST SUNDAY MORNING AHEAD OF AN APPROACHING CLIPPER SYSTEM. && .APX WATCHES/WARNINGS/ADVISORIES... MI...WINTER WEATHER ADVISORY UNTIL 11 AM EST THIS MORNING FOR MIZ008- 015>017-019>022-025>028-031>033. LH...NONE. LM...GALE WARNING UNTIL 5 PM EST THIS AFTERNOON FOR LMZ344>346. LS...NONE. && $$ UPDATE...JPB SYNOPSIS...MR SHORT TERM...MB LONG TERM...MR AVIATION...MR MARINE...MB
AREA FORECAST DISCUSSION
NWS GAYLORD MI
635 AM EST SAT JAN 25 2014 .SYNOPSIS... ISSUED AT 300 AM EST SAT JAN 25 2014 AN ALBERTA CLIPPER SYSTEM AND ARCTIC FRONT WILL CONTINUE TO ROLL THROUGH THE REGION THIS MORNING...BRINGING LAKE ENHANCED SNOW THROUGH TONIGHT. GUSTY SOUTHWEST WINDS WILL SHIFT TO THE NORTHWEST THIS MORNING...LEADING TO MORE BLOWING AND DRIFTING SNOW. ANOTHER CLIPPER SYSTEM WILL BRING ANOTHER ROUND OF ACCUMULATING SNOW FOR SUNDAY. BITTERLY COLD TEMPERATURES WILL CONTINUE THROUGH THE WEEKEND AND INTO EARLY NEXT WEEK. TEMPERATURES WILL GRADUALLY MODERATE LATE NEXT WEEK. && .UPDATE... ISSUED AT 635 AM EST SAT JAN 25 2014 WIDESPREAD SYNOPTIC SNOW EVENT CONTINUES TO EVOLVE INTO A GUSTY NW FLOW LAKE EFFECT SNOW EVENT IN THE WAKE OF A STRONG COLD FRONT THAT IS CURRENTLY EXITING EAST OUT OUR CWA. NW WINDS GUSTING TO 15 KTS ARE PUSHING LAKE SNOW SHOWERS FURTHER INLAND INTO N CENTRAL AND EVEN PORTIONS OF NE LWR MICHIGAN ATTM. EXPECT COVERAGE OF SNOW SHOWERS WILL GRADUALLY ORGANIZE INTO MORE OF A TRUE NW FLOW PATTERN...IMPACTING MAINLY WRN CHIPPEWA AND MACKINAC COUNTIES WHERE OPEN UPSTREAM LAKE SUPERIOR WATER WILL RESULT IN DOWNSTREAM LAKE SNOW PRODUCTION...AND IMPACTING MAINLY NW AND N CENTRAL LWR MICHIGAN ALONG AND WEST OF I-75. THESE AREAS WILL SEE ANOTHER INCH OR TWO OF NEW SNOW TODAY...WITH GUSTY NW WINDS CONTINUING TO CAUSE SIGNIFICANT BLOWING AND DRIFTING SNOW, WILL KEEP ALL WINTER WX ADVISORIES IN EFFECT THRU THE MORNING. CAA HAS COMMENCED BEHIND THE COLD FRONT. OVERNIGHT TEMPS IN THE 20S HAVE DROPPED INTO THE TEENS...AND EXPECT TEMPS WILL CONTINUE TO DROP THROUGHOUT THE DAY. NW WINDS GUSTING TO 25 KTS COMBINED WITH TEMPS PLUMMETING INTO THE SINGLE DIGITS TODAY...WIND CHILLS WILL FALL TO AROUND -20. STAY WARM FOLKS! && .SHORT TERM...(TODAY THROUGH TONIGHT) ISSUED AT 300 AM EST SAT JAN 25 2014 ANOTHER FORECAST...AND ANOTHER ROUND OF HIGH IMPACT WEATHER CONDITIONS. SYSTEM RESPONSIBLE FOR YESTERDAYS DOWNRIGHT DANGEROUS WEATHER STILL IMPACTING OUR AREA...WITH ARCTIC FRONT MAKING STEADY SOUTHEAST PROGRESS ACROSS NORTHERN LOWER MICHIGAN. WINDS STILL A`BLOWING...BUT NOTHING EVEN REMOTELY CLOSE TO THOSE OBSERVED YESTERDAY. WIDESPREAD MAINLY LIGHT SNOW CONTINUES AHEAD OF THIS FRONT...WITH CORE OF MID LEVEL UPWARD QG SUPPORT ASSISTING FRONTAL DRIVEN CONVERGENCE TO DRIVE SUCH. LAKE PROCESSES REALLY STARTING TO RAMP UP ON LAKE SUPERIOR...AS NOTED BY KMQT AND MONTREAL RIVER RADARS AS WELL AS IR SATELLITE IMAGERY. DEEP MID LEVEL GYRE DRIVING ALL THE ABOVE ROTATING ON THE SOUTH SHORE OF HUDSON BAY...WITH DEEP NORTHWEST FLOW ON ITS BACKSIDE DIVING RIGHT FROM THE ARCTIC INTO THE NORTHERN LAKES. LATEST HIGH RES RAP GUIDANCE SHOWS NEGATIVE 20C H8 AIR ALREADY DIGGING ACROSS LAKE SUPERIOR...WITH SIMPLY NOTHING TO STOP AS IT SETS ITS SIGHTS ON THE REST OF THE AREA THROUGH THIS MORNING. FORECAST CHALLENGES THROUGH THE SHORT TERM FALL OUT OF THE ABOVE...WITH HIGHER IMPACT TEMPERATURE TRENDS AND LAKE INDUCED SNOW ACCUMULATIONS THE MAIN PRIORITY. SYNOPTIC SNOWS GIVE WAY TO MORE MESOSCALE LAKE DRIVEN PROCESSES HEADING THROUGH TODAY AS ARCTIC FRONT SLIPS STAGE RIGHT BY SUNRISE. INTENSE CAA CONTINUES TO INCREASE OVER-WATER INSTABILITY AS H8 TEMPERATURES FALL THROUGH THE NEGATIVE MIDDLE 20S CELSIUS. NORTHWEST FLOW ESSENTIALLY LOCKED IN THROUGH THE DAY...WITH DECENT MOISTURE PROFILES AND INVERSION LEVELS UP THROUGH H7 SUPPORTING GOOD LAKE CONTRIBUTION. CONDITIONS OFF LAKE SUPERIOR LOOK QUITE INTERESTING INDEED...WITH NARROWING OF OPEN WATER CHANNEL OVER THE CENTER PART OF THE LAKE RESULTING IN ENHANCED LOW LEVEL CONVERGENCE AXIS. TRENDS SUPPORT THIS ENHANCED BAND SETTING UP EARLY THIS MORNING... ESPECIALLY TARGETING LUCE COUNTY...PERHAPS CLIPPING FAR WESTERN MACKINAC AND CHIPPEWA COUNTIES. LOSS OF DGZ FAVORS LOW SNOW/LIQUID RATIOS...HELPING KEEP AMOUNTS IN CHECK. WILL TENTATIVELY HAVE A FEW INCHES OF SNOW IN FAVORED AREAS...TAPERING AMOUNTS QUICKLY AS ONE HEADS EAST. FOCUSED CONVERGENCE FROM LAKE SUPERIOR BAND LOOKS TO SPILL SOUTH INTO NORTHWEST LOWER...ALTHOUGH EXTENSIVE NORTHERN LAKE MICHIGAN ICE COVER WILL TAKE ITS TOLL ON SNOWFALL INTENSITY. OTHERWISE...TYPICAL MULTI-BANDED SNOW SHOWERS WILL IMPACT FAVORED AREAS OF NORTHWEST LOWER...WITH COLD TEMPERATURE PROFILES (THAT SMALL NON-FLUFF PRODUCING FLAKE THING) OFFSETTING GOOD THERMODYNAMICS. CAN SEE A FEW INCHES AT MOST WHERE BANDS REMAIN MOST PERSISTENT. DEEP MIXED LAYER WILL CONTINUE TO TAP INTO RELATIVELY STRONG WINDS JUST OFF THE DECK...CONTINUING THE GUSTY WINDS ACROSS THE REGION. BLOWING/DRIFTING SNOW WILL RESULT...WITH PERIODS OF REDUCED VISIBILITIES...ESPECIALLY IN OPEN AREAS. TEMPERATURES WILL TREND DOWN FROM EARLY MORNING READINGS IN THE SINGLE DIGITS AND TEENS...WITH READINGS AT LEAST A FEW DEGREES BELOW ZERO FOR NORTHEAST EAST UPPER MICHIGAN BY LATER THIS AFTERNOON. WIND CHILL VALUES WILL RUN IN THE TEENS BELOW ZERO...PUSHING THE NEGATIVE LOWER 20S LATER THIS AFTERNOON. ANOTHER HARSH WINTER DAY INDEED! AS FOR HEADLINES: SNOW AMOUNTS/WIND CHILL VALUES DEFINITELY DO NOT JUSTIFY AN EXTENSION OF CURRENT HEADLINES INTO TODAY. THAT SAID...HIGH IMPACT EVENT YESTERDAY/OVERNIGHT RESULTING IN CONTINUATION OF SNOW-COVERED ROADS...WITH SOME LIKELY NEARLY IMPASSABLE IN EXPOSED AREAS. FALLING PIXIE DUST SNOWS WILL ONLY ADD TO THE LOW VISIBILITY PRODUCED BY BLOWING/DRIFTING SNOW ALREADY ON THE GROUND. DON`T WANT TO GIVE THE IMPRESSION ALL IS CLEAR BY DROPPING THE HEADLINE...ESPECIALLY IN THE HARDER HIT AREAS ALONG AND WEST OF INTERSTATE 75. FOR SIMPLICITY...WILL EXTEND THE ADVISORY (DOWNGRADING THOSE IN WARNING) THROUGH THIS MORNING. EASTWARD DISPLACED LAKE SUPERIOR CONVERGENCE BAND AND/OR BETTER THAN ANTICIPATED LAKE SNOWS OVER NORTHWEST LOWER MAY RESULT IN FURTHER EXTENSIONS BY THE DAY CREW. TONIGHT...LAKE SNOWS CONTINUE...ALBEIT AT A LIGHTER INTENSITY GIVEN LOSS OF SYNOPTIC MOISTURE AND FALLING INVERSION HEIGHTS. MAY SEE SOME LINGERING BETTER SNOWS ACROSS EASTERN UPPER UNDER REMNANT CONVERGENCE AXIS THIS EVENING...BUT EVEN THESE SHOULD NOT ADD UP TO TOO MUCH. EVEN WITH PLENTY OF CLOUDS AND SOME LIGHT WINDS... TEMPERATURES BY MORNING EXPECTED TO DROP WELL BELOW ZERO AWAY FROM LAKE MICHIGAN. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 300 AM EST SAT JAN 25 2014 SUNDAY AND MONDAY...OUR NEXT LOW PRESSURE SYSTEM QUICKLY ENTERS THE WRN GREAT LAKES REGION EARLY SUNDAY AS THE SURFACE RIDGE AXIS PUSHES EAST OF MICHIGAN. MOIST ISENTROPIC ASCENT (I280) WILL DEVELOP FROM SW TO NE ACROSS OUR CWA SUNDAY MORNING AS WAA PATTERN SETS UP AHEAD OF THE SURFACE LOW...WITH ISENTROPIC LIFT PERSISTING THRU THE AFTERNOON. SURFACE LOW CENTER WILL TRACK THRU LOWER MICHIGAN SUNDAY EVENING...PUSHING EAST OF MICHIGAN LATE SUNDAY NIGHT. WIDESPREAD SNOW WILL DEVELOP FROM SW TO NE SUNDAY RIGHT IN LINE WITH THE ISENTROPIC ASCENT PATTERN. APPEARS THAT VIRTUALLY ALL OF OUR CWA WILL SEE SOME SNOWFALL FROM THIS SYSTEM...AND HAVE INCREASED POPS TO CATEGORICAL EVERYWHERE FOR SUNDAY AFTERNOON AND EVENING. OVERALL SYNOPTIC SNOWFALL WILL BE A GENERAL 2 TO 4 INCHES ACROSS OUR ENTIRE CWA FOR SUNDAY AND SUNDAY NIGHT. N/NW LOW LEVEL FLOW ON THE BACKSIDE OF THE LOW CENTER WILL TARGET OUR SW CWA ALONG AND WEST OF US-131 FOR LAKE ENHANCED SNOW SHOWERS SUNDAY NIGHT...WHICH SHOULD BOOST SNOWFALL TOTALS TO 4 TO 6 INCHES FOR SUNDAY AND SUNDAY NIGHT. SURFACE LOW WILL CONTINUE TO EXIT EASTWARD AWAY FROM MICHIGAN ON MONDAY. SYNOPTIC SNOW WILL COME TO AN END BY 12Z MONDAY... TRANSITIONING TO PRIMARILY A W/NW FLOW LAKE EFFECT REGIME. CATEGORICAL SNOWFALL WILL CONTINUE MONDAY AND MONDAY NIGHT FOR THE TYPICAL SNOWBELT AREAS...NAMELY NW CHIPPEWA COUNTY AND NW LWR MICHIGAN WEST OF I-75. HOWEVER...THE BIG STORY WILL BE THE FRIGID TEMPS. HIGH TEMPS MONDAY AFTERNOON WILL STRUGGLE TO WARM INTO THE SINGLE DIGITS ABOVE ZERO...AND SOME PLACES MAY VERY WELL NOT WARM INTO POSITIVE NUMBERS. THIS COLD AIRMASS WILL NOT SUPPORT LARGE FLAKE GROWTH...SO ADDITIONAL SNOW AMOUNTS FOR MONDAY AND MONDAY NIGHT WILL BE RELATIVELY MINOR (I.E. UP TO 2 INCHES FOR THE ENTIRE 24 HOUR PERIOD). TUESDAY THRU FRIDAY...WESTERLY FLOW LAKE EFFECT SNOW SHOWERS WILL CONTINUE INTO TUESDAY AS A WAVE SWINGS THRU NRN MICHIGAN ALONG THE BASE OF THE 500 MB TROUGH...PROVIDING SOME SYNOPTIC ENHANCEMENT TO ONGOING LAKE EFFECT EVENT. NARROW/FLATTENING UPPER RIDGE AXIS WILL QUICKLY PASS THRU MICHIGAN ON WEDNESDAY...WITH LOW LEVEL FLOW BACKING TO THE SW IMMEDIATELY BEHIND IT. LATEST ECMWF SUGGESTS A SLIGHT CHANGE IN THE OVERALL UPPER LEVEL PATTERN FOR THE LAST HALF OF THE WEEK AS DEEP UPPER TROUGHING SLIDES EAST AND IS GENERALLY REPLACED WITH A MORE ZONAL FLOW. THERE WILL BE ONE GLANCING BLOW FROM AN UPPER TROUGH ON THURSDAY AS A COLD FRONT SWEEPS THRU MICHIGAN. OTHERWISE...FOR WEDNESDAY...SW FLOW AHEAD OF THAT COLD FRONT WILL BOOST AFTERNOON TEMPS INTO THE TEENS...WHILE REDIRECTING FOCUS OF LAKE EFFECT SNOW SHOWERS TO THE STRAITS AND THE LAKE MICHIGAN SHORELINE COUNTIES. OUR ENTIRE CWA WILL SEE A GOOD CHANCE OF SNOW ON THURSDAY ALONG AND AHEAD OF THE COLD FRONT. AGAIN...THE COLD AIR BEHIND THIS FRONT WILL BE A GLANCING BLOW AS LOW LEVEL FLOW QUICKLY SHIFTS BACK TO THE SW ON FRIDAY. OVER-LAKE INSTABILITY WILL QUICKLY WANE ON FRIDAY AS 850 MB TEMPS WARM TO -10 TO -12 C... PRODUCING VERY MARGINAL INSTABILITY AND THUS VERY SMALL CHANCES OF SNOW. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 635 AM EST SAT JAN 25 2014 LAKE EFFECT SNOW SHOWERS AND NW WINDS GUSTING TO 25 KTS WILL CONTINUE TO IMPACT ALL NRN LWR MICHIGAN TAF SITES TODAY AND TONIGHT...FREQUENTLY DROPPING CONDITIONS TO MVFR/IFR WITHIN THESE SNOW SHOWERS. SNOW SHOWERS WILL MAINLY IMPACT NW LWR MICHIGAN TAF SITES TONIGHT AS NW WINDS DIMINISH TO 10 TO 15 KTS AND SHIFT TO THE WEST. && .MARINE... ISSUED AT 300 AM EST SAT JAN 25 2014 STRONG CAA WILL LEAD TO GALE PRODUCING NORTHWEST WIND GUSTS ACROSS LAKE MICHIGAN TODAY. WINDS SUBSIDE SOME TONIGHT...ALTHOUGH SCA CONDITIONS ARE EXPECTED. WINDS BACK AND BECOME LIGHT SOUTHWEST SUNDAY MORNING AHEAD OF AN APPROACHING CLIPPER SYSTEM. && .APX WATCHES/WARNINGS/ADVISORIES... MI...WINTER WEATHER ADVISORY UNTIL 11 AM EST THIS MORNING FOR MIZ008- 015>017-019>022-025>028-031>033. LH...NONE. LM...GALE WARNING UNTIL 5 PM EST THIS AFTERNOON FOR LMZ344>346. LS...NONE. && $$ UPDATE...MR SYNOPSIS...MR SHORT TERM...MB LONG TERM...MR AVIATION...MR MARINE...MB
AREA FORECAST DISCUSSION
NWS GAYLORD MI
300 AM EST SAT JAN 25 2014 .SYNOPSIS... ISSUED AT 300 AM EST SAT JAN 25 2014 AN ALBERTA CLIPPER SYSTEM AND ARCTIC FRONT WILL CONTINUE TO ROLL THROUGH THE REGION THIS MORNING...BRINGING LAKE ENHANCED SNOW THROUGH TONIGHT. GUSTY SOUTHWEST WINDS WILL SHIFT TO THE NORTHWEST THIS MORNING...LEADING TO MORE BLOWING AND DRIFTING SNOW. ANOTHER CLIPPER SYSTEM WILL BRING ANOTHER ROUND OF ACCUMULATING SNOW FOR SUNDAY. BITTERLY COLD TEMPERATURES WILL CONTINUE THROUGH THE WEEKEND AND INTO EARLY NEXT WEEK. TEMPERATURES WILL GRADUALLY MODERATE LATE NEXT WEEK. && .SHORT TERM...(TODAY THROUGH TONIGHT) ISSUED AT 300 AM EST SAT JAN 25 2014 ANOTHER FORECAST...AND ANOTHER ROUND OF HIGH IMPACT WEATHER CONDITIONS. SYSTEM RESPONSIBLE FOR YESTERDAYS DOWNRIGHT DANGEROUS WEATHER STILL IMPACTING OUR AREA...WITH ARCTIC FRONT MAKING STEADY SOUTHEAST PROGRESS ACROSS NORTHERN LOWER MICHIGAN. WINDS STILL A`BLOWING...BUT NOTHING EVEN REMOTELY CLOSE TO THOSE OBSERVED YESTERDAY. WIDESPREAD MAINLY LIGHT SNOW CONTINUES AHEAD OF THIS FRONT...WITH CORE OF MID LEVEL UPWARD QG SUPPORT ASSISTING FRONTAL DRIVEN CONVERGENCE TO DRIVE SUCH. LAKE PROCESSES REALLY STARTING TO RAMP UP ON LAKE SUPERIOR...AS NOTED BY KMQT AND MONTREAL RIVER RADARS AS WELL AS IR SATELLITE IMAGERY. DEEP MID LEVEL GYRE DRIVING ALL THE ABOVE ROTATING ON THE SOUTH SHORE OF HUDSON BAY...WITH DEEP NORTHWEST FLOW ON ITS BACKSIDE DIVING RIGHT FROM THE ARCTIC INTO THE NORTHERN LAKES. LATEST HIGH RES RAP GUIDANCE SHOWS NEGATIVE 20C H8 AIR ALREADY DIGGING ACROSS LAKE SUPERIOR...WITH SIMPLY NOTHING TO STOP AS IT SETS ITS SIGHTS ON THE REST OF THE AREA THROUGH THIS MORNING. FORECAST CHALLENGES THROUGH THE SHORT TERM FALL OUT OF THE ABOVE...WITH HIGHER IMPACT TEMPERATURE TRENDS AND LAKE INDUCED SNOW ACCUMULATIONS THE MAIN PRIORITY. SYNOPTIC SNOWS GIVE WAY TO MORE MESOSCALE LAKE DRIVEN PROCESSES HEADING THROUGH TODAY AS ARCTIC FRONT SLIPS STAGE RIGHT BY SUNRISE. INTENSE CAA CONTINUES TO INCREASE OVER-WATER INSTABILITY AS H8 TEMPERATURES FALL THROUGH THE NEGATIVE MIDDLE 20S CELSIUS. NORTHWEST FLOW ESSENTIALLY LOCKED IN THROUGH THE DAY...WITH DECENT MOISTURE PROFILES AND INVERSION LEVELS UP THROUGH H7 SUPPORTING GOOD LAKE CONTRIBUTION. CONDITIONS OFF LAKE SUPERIOR LOOK QUITE INTERESTING INDEED...WITH NARROWING OF OPEN WATER CHANNEL OVER THE CENTER PART OF THE LAKE RESULTING IN ENHANCED LOW LEVEL CONVERGENCE AXIS. TRENDS SUPPORT THIS ENHANCED BAND SETTING UP EARLY THIS MORNING... ESPECIALLY TARGETING LUCE COUNTY...PERHAPS CLIPPING FAR WESTERN MACKINAC AND CHIPPEWA COUNTIES. LOSS OF DGZ FAVORS LOW SNOW/LIQUID RATIOS...HELPING KEEP AMOUNTS IN CHECK. WILL TENTATIVELY HAVE A FEW INCHES OF SNOW IN FAVORED AREAS...TAPERING AMOUNTS QUICKLY AS ONE HEADS EAST. FOCUSED CONVERGENCE FROM LAKE SUPERIOR BAND LOOKS TO SPILL SOUTH INTO NORTHWEST LOWER...ALTHOUGH EXTENSIVE NORTHERN LAKE MICHIGAN ICE COVER WILL TAKE ITS TOLL ON SNOWFALL INTENSITY. OTHERWISE...TYPICAL MULTI-BANDED SNOW SHOWERS WILL IMPACT FAVORED AREAS OF NORTHWEST LOWER...WITH COLD TEMPERATURE PROFILES (THAT SMALL NON-FLUFF PRODUCING FLAKE THING) OFFSETTING GOOD THERMODYNAMICS. CAN SEE A FEW INCHES AT MOST WHERE BANDS REMAIN MOST PERSISTENT. DEEP MIXED LAYER WILL CONTINUE TO TAP INTO RELATIVELY STRONG WINDS JUST OFF THE DECK...CONTINUING THE GUSTY WINDS ACROSS THE REGION. BLOWING/DRIFTING SNOW WILL RESULT...WITH PERIODS OF REDUCED VISIBILITIES...ESPECIALLY IN OPEN AREAS. TEMPERATURES WILL TREND DOWN FROM EARLY MORNING READINGS IN THE SINGLE DIGITS AND TEENS...WITH READINGS AT LEAST A FEW DEGREES BELOW ZERO FOR NORTHEAST EAST UPPER MICHIGAN BY LATER THIS AFTERNOON. WIND CHILL VALUES WILL RUN IN THE TEENS BELOW ZERO...PUSHING THE NEGATIVE LOWER 20S LATER THIS AFTERNOON. ANOTHER HARSH WINTER DAY INDEED! AS FOR HEADLINES: SNOW AMOUNTS/WIND CHILL VALUES DEFINITELY DO NOT JUSTIFY AN EXTENSION OF CURRENT HEADLINES INTO TODAY. THAT SAID...HIGH IMPACT EVENT YESTERDAY/OVERNIGHT RESULTING IN CONTINUATION OF SNOW-COVERED ROADS...WITH SOME LIKELY NEARLY IMPASSABLE IN EXPOSED AREAS. FALLING PIXIE DUST SNOWS WILL ONLY ADD TO THE LOW VISIBILITY PRODUCED BY BLOWING/DRIFTING SNOW ALREADY ON THE GROUND. DON`T WANT TO GIVE THE IMPRESSION ALL IS CLEAR BY DROPPING THE HEADLINE...ESPECIALLY IN THE HARDER HIT AREAS ALONG AND WEST OF INTERSTATE 75. FOR SIMPLICITY...WILL EXTEND THE ADVISORY (DOWNGRADING THOSE IN WARNING) THROUGH THIS MORNING. EASTWARD DISPLACED LAKE SUPERIOR CONVERGENCE BAND AND/OR BETTER THAN ANTICIPATED LAKE SNOWS OVER NORTHWEST LOWER MAY RESULT IN FURTHER EXTENSIONS BY THE DAY CREW. TONIGHT...LAKE SNOWS CONTINUE...ALBEIT AT A LIGHTER INTENSITY GIVEN LOSS OF SYNOPTIC MOISTURE AND FALLING INVERSION HEIGHTS. MAY SEE SOME LINGERING BETTER SNOWS ACROSS EASTERN UPPER UNDER REMNANT CONVERGENCE AXIS THIS EVENING...BUT EVEN THESE SHOULD NOT ADD UP TO TOO MUCH. EVEN WITH PLENTY OF CLOUDS AND SOME LIGHT WINDS... TEMPERATURES BY MORNING EXPECTED TO DROP WELL BELOW ZERO AWAY FROM LAKE MICHIGAN. && .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 300 AM EST SAT JAN 25 2014 SUNDAY AND MONDAY...OUR NEXT LOW PRESSURE SYSTEM QUICKLY ENTERS THE WRN GREAT LAKES REGION EARLY SUNDAY AS THE SURFACE RIDGE AXIS PUSHES EAST OF MICHIGAN. MOIST ISENTROPIC ASCENT (I280) WILL DEVELOP FROM SW TO NE ACROSS OUR CWA SUNDAY MORNING AS WAA PATTERN SETS UP AHEAD OF THE SURFACE LOW...WITH ISENTROPIC LIFT PERSISTING THRU THE AFTERNOON. SURFACE LOW CENTER WILL TRACK THRU LOWER MICHIGAN SUNDAY EVENING...PUSHING EAST OF MICHIGAN LATE SUNDAY NIGHT. WIDESPREAD SNOW WILL DEVELOP FROM SW TO NE SUNDAY RIGHT IN LINE WITH THE ISENTROPIC ASCENT PATTERN. APPEARS THAT VIRTUALLY ALL OF OUR CWA WILL SEE SOME SNOWFALL FROM THIS SYSTEM...AND HAVE INCREASED POPS TO CATEGORICAL EVERYWHERE FOR SUNDAY AFTERNOON AND EVENING. OVERALL SYNOPTIC SNOWFALL WILL BE A GENERAL 2 TO 4 INCHES ACROSS OUR ENTIRE CWA FOR SUNDAY AND SUNDAY NIGHT. N/NW LOW LEVEL FLOW ON THE BACKSIDE OF THE LOW CENTER WILL TARGET OUR SW CWA ALONG AND WEST OF US-131 FOR LAKE ENHANCED SNOW SHOWERS SUNDAY NIGHT...WHICH SHOULD BOOST SNOWFALL TOTALS TO 4 TO 6 INCHES FOR SUNDAY AND SUNDAY NIGHT. SURFACE LOW WILL CONTINUE TO EXIT EASTWARD AWAY FROM MICHIGAN ON MONDAY. SYNOPTIC SNOW WILL COME TO AN END BY 12Z MONDAY... TRANSITIONING TO PRIMARILY A W/NW FLOW LAKE EFFECT REGIME. CATEGORICAL SNOWFALL WILL CONTINUE MONDAY AND MONDAY NIGHT FOR THE TYPICAL SNOWBELT AREAS...NAMELY NW CHIPPEWA COUNTY AND NW LWR MICHIGAN WEST OF I-75. HOWEVER...THE BIG STORY WILL BE THE FRIGID TEMPS. HIGH TEMPS MONDAY AFTERNOON WILL STRUGGLE TO WARM INTO THE SINGLE DIGITS ABOVE ZERO...AND SOME PLACES MAY VERY WELL NOT WARM INTO POSITIVE NUMBERS. THIS COLD AIRMASS WILL NOT SUPPORT LARGE FLAKE GROWTH...SO ADDITIONAL SNOW AMOUNTS FOR MONDAY AND MONDAY NIGHT WILL BE RELATIVELY MINOR (I.E. UP TO 2 INCHES FOR THE ENTIRE 24 HOUR PERIOD). TUESDAY THRU FRIDAY...WESTERLY FLOW LAKE EFFECT SNOW SHOWERS WILL CONTINUE INTO TUESDAY AS A WAVE SWINGS THRU NRN MICHIGAN ALONG THE BASE OF THE 500 MB TROUGH...PROVIDING SOME SYNOPTIC ENHANCEMENT TO ONGOING LAKE EFFECT EVENT. NARROW/FLATTENING UPPER RIDGE AXIS WILL QUICKLY PASS THRU MICHIGAN ON WEDNESDAY...WITH LOW LEVEL FLOW BACKING TO THE SW IMMEDIATELY BEHIND IT. LATEST ECMWF SUGGESTS A SLIGHT CHANGE IN THE OVERALL UPPER LEVEL PATTERN FOR THE LAST HALF OF THE WEEK AS DEEP UPPER TROUGHING SLIDES EAST AND IS GENERALLY REPLACED WITH A MORE ZONAL FLOW. THERE WILL BE ONE GLANCING BLOW FROM AN UPPER TROUGH ON THURSDAY AS A COLD FRONT SWEEPS THRU MICHIGAN. OTHERWISE...FOR WEDNESDAY...SW FLOW AHEAD OF THAT COLD FRONT WILL BOOST AFTERNOON TEMPS INTO THE TEENS...WHILE REDIRECTING FOCUS OF LAKE EFFECT SNOW SHOWERS TO THE STRAITS AND THE LAKE MICHIGAN SHORELINE COUNTIES. OUR ENTIRE CWA WILL SEE A GOOD CHANCE OF SNOW ON THURSDAY ALONG AND AHEAD OF THE COLD FRONT. AGAIN...THE COLD AIR BEHIND THIS FRONT WILL BE A GLANCING BLOW AS LOW LEVEL FLOW QUICKLY SHIFTS BACK TO THE SW ON FRIDAY. OVER-LAKE INSTABILITY WILL QUICKLY WANE ON FRIDAY AS 850 MB TEMPS WARM TO -10 TO -12 C... PRODUCING VERY MARGINAL INSTABILITY AND THUS VERY SMALL CHANCES OF SNOW. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 1152 PM EST FRI JAN 24 2014 IFR TONIGHT IN SN...SOME IMPROVEMENT SATURDAY. SNOW CONTINUES IN WARM ADVECTION PATTERN...AND WILL UNTIL A COLD FRONT MOVES IN OVERNIGHT. WIDESPREAD IFR CONDITIONS UNTIL THEN. BEHIND THE FRONT...QUICK TRANSITION TO LAKE EFFECT SNOW NEAR LAKE MI...WITH TVC GETTING THE WORST OF IT ON SATURDAY. OTHER SITES WILL TRANSITION TO MVFR/VFR. WINDS VEER NW AND INCREASE AGAIN BEHIND THE FRONT...WITH BLSN RETURNING. && .MARINE... ISSUED AT 300 AM EST SAT JAN 25 2014 STRONG CAA WILL LEAD TO GALE PRODUCING NORTHWEST WIND GUSTS ACROSS LAKE MICHIGAN TODAY. WINDS SUBSIDE SOME TONIGHT...ALTHOUGH SCA CONDITIONS ARE EXPECTED. WINDS BACK AND BECOME LIGHT SOUTHWEST SUNDAY MORNING AHEAD OF AN APPROACHING CLIPPER SYSTEM. && .APX WATCHES/WARNINGS/ADVISORIES... MI...WINTER WEATHER ADVISORY UNTIL 11 AM EST THIS MORNING FOR MIZ008- 015>017-019>022-025>028-031>033. LH...NONE. LM...GALE WARNING UNTIL 5 PM EST THIS AFTERNOON FOR LMZ344>346. LS...NONE. && $$ SYNOPSIS...MR SHORT TERM...MB LONG TERM...MR AVIATION...JZ MARINE...MB
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1243 PM EST FRI JAN 24 2014 LATEST UPDATE... AVIATION .SYNOPSIS... ISSUED AT 324 AM EST FRI JAN 24 2014 CONDITIONS WILL GRADUALLY DETERIORATE THROUGH THE DAY TODAY ACROSS THE AREA. WINDS WILL INCREASE THIS MORNING WHERE WIND GUSTS OF 40 MPH OR MORE WILL BECOME LIKELY. THIS WIND IS EXPECTED TO PRODUCE BLOWING AND DRIFTING SNOW WITH RECENT SNOW THAT HAS FALLEN ACROSS THE AREA. THE BLOWING AND DRIFTING WILL BECOME WORSE THIS AFTERNOON AS ADDITIONAL SNOW DEVELOPS FROM NORTH TO SOUTH. SNOW WILL CONTINUE INTO TONIGHT BEFORE IT BECOMES MORE LOCALIZED LAKE EFFECT ON SATURDAY. ANOTHER SYSTEM WILL MOVE INTO THE AREA FOR THE DAY ON SUNDAY AND SUNDAY NIGHT. THIS WILL BRING ANOTHER ROUND OF SNOW TO THE AREA ALONG WITH MORE WIND AND COLD AIR. THIS COULD PRODUCE A GOOD DEAL OF IMPACT TO THE AREA WITH BLOWING AND DRIFTING SNOW POSSIBLE. MORE COLD AIR AND LAKE EFFECT WILL RULE INTO MUCH OF NEXT WEEK. && .UPDATE... ISSUED AT 1008 AM EST FRI JAN 24 2014 OUR CURRENT FORECAST IS ON TRACK. THE LAKE ENHANCED SOUTHWEST FLOW SNOW EVENT IS STARTING TO INCREASE AND SHOULD BE GOING STRONG BETWEEN 1 PM AND 5 PM. THERE MAY BE A SORT OF LULL FOR A FEW HOURS THEN THE MORE SYNOPTIC PART OF THE STORM KICKS IN AROUND 7 PM AND SHOULD GO TILL AROUND 6 AM. IT DURING THAT TIME MOST OF THE SNOWFALL WILL OCCUR. AS OF 10 AM WE HAVE WIND CHILLS OF 15 TO 25 BELOW OVER MOST OF OUR CENTRAL AND SOUTHERN CWA AND BETWEEN 5 AND 15 BELOW NORTH OF THERE. AS THE WIND INCREASES TEMPERATURES WILL ALSO RISE SO I EXPECT OVERALL THE WIND CHILLS TO WARM SOME...BEING IN THE 0 TO 10 BELOW RANGE BY LATE AFTERNOON. THE LATEST RAP AND NAM SHOW THE LAKE SHORE COUNTIES WILL HAVE 50 TO 55 KNOTS IN THE MIXED LAYER (3000 FT IN DEPTH) FROM 1 PM TILL 5 PM THIS AFTERNOON. EVEN WITH GUSTS OF 25-30 MPH RANGE MKG...GRR AND BIV HAVE VISIBILITIES UNDER 3 MILES IN SNOW AND BLOWING SNOW. ONCE THE SNOW RATES INCREASE BY EARLY AFTERNOON WITH WINDS GUSTING NEAR 40 MPH WE WILL BE SEEING NEAR BLIZZARD CONDITIONS. WE WILL HAVE TO MONITOR THIS TO SEE IF WE NEED TO UPGRADE TO BLIZZARD WARNING... HOWEVER AT THIS TIME IT STILL SEEMS TO ME WE CAN GO AHEAD WITH THE WINTER STORM WARNINGS/ADVISORIES AS THEY ARE. ONE OTHER ISSUE TO ADDRESS LATER IS THE LAKE EFFECT BEHIND THE STORM SATURDAY. I COULD SEE EXPANDED THE WARNING INTO SATURDAY AFTERNOON FOR THE COUNTIES ALONG AND WEST OF US-131. && .SHORT TERM...(TODAY THROUGH SATURDAY NIGHT) ISSUED AT 324 AM EST FRI JAN 24 2014 OBVIOUSLY THE MAIN FOCUS OF THE SHORT TERM IS THE EVENT EXPECTED FOR TODAY INTO THE FIRST PORTION OF SATURDAY WITH THE STRONGER SYSTEM EXPECTED TO DROP THROUGH THE AREA. WE WILL NOT BE MAKING ANY CHANGES TO THE HEADLINES WITH THIS FCST PACKAGE. WE HAVE INCREASED SNOW TOTALS A BIT ACROSS THE NRN PORTION OF THE WARNING AREA AS CONDITIONS LOOK A BIT MORE FAVORABLE FOR BETTER ACCUMULATIONS. THE RELATIVE CALM BEFORE THE STORM IS CURRENTLY MOVING IN THIS MORNING. RESIDUAL LAKE EFFECT HAS DIMINISHED TO FLURRIES AS THE UPPER JET IS SHIFTING OUT OF THE AREA AND SHORT WAVE RIDGING BUILDS IN. CLOUDS HOLDING IN THUS FAR HAVE KEPT TEMPS AND RESULTING WIND CHILLS IN CHECK. WE DO EXPECT WIND CHILLS TO DROP OVER THE NEXT FEW HOURS AS CLEARING FROM THE S WILL MOVE IN ACROSS THE SE WITH THE FLOW GOING SW. WINDS WILL START PICKING UP AND DRIVE THE WIND CHILLS DOWN THIS MORNING. WINDS WILL ONLY INCREASE THIS MORNING...AND REALLY GET CRANKING AROUND MID MORNING. THE STRONGEST WINDS LOOK TO OCCUR CENTERED AROUND 18Z +/- A COUPLE OF HOURS DEPENDING ON THE LOCATION. WE CONTINUE TO EXPECT WIND GUSTS UP TO 40-45 MPH WITH SOME HIGHER GUSTS ALONG THE IMMEDIATE LAKESHORE. THESE WINDS WILL BE INCREASING WHILE LITTLE TO NO SNOW IS FALLING THIS MORNING. THE WINDS WILL HAVE THE FRESH SNOW FROM THE LAST COUPLE OF DAYS TO PRODUCE BLOWING AND DRIFTING. HOW MUCH REDUCTION IN VISIBILITY BEFORE ADDITIONAL SNOW STARTS FALLING IS UNCERTAIN. THIS IS ONE REASON WE ARE HOLDING OFF ON A POSSIBLE UPGRADE TO A BLIZZARD WARNING. SNOW WILL DEVELOP UP NORTH WITH THE BETTER WINDS STILL IN PLACE...SO THE WARNING AREA UP NORTH WILL NEED TO BE MONITORED A BIT CLOSER. THE WORST BLOWING AND DRIFTING SNOW WILL OCCUR WHILE THE WINDS ARE STILL UP THIS AFTERNOON AND AS THE SNOW GRADUALLY DEVELOPS TO THE SOUTH. THIS SNOW PORTION OF THE EVENT WILL BE A COMBINATION OF ISENTROPIC ASCENT AND LAKE ENHANCEMENT WITH DELTA T/S EXPECTED TO BE IN THE MIDDLE TEENS C BY THAT TIME. MODELS ARE INDICATING SOME FAIRLY ROBUST CONVERGENCE ACROSS THE NW CORNER OF THE CWFA LIKELY DUE TO THE WINDS COMING OFF OF THE LAKE AND DUE TO THE FLOW AND THE CONTOUR OF THE COAST. THIS WILL ALLOW FOR SOME LOCALLY HEAVIER BANDS SIMILAR TO THE EVENT EARLIER THIS WEEK. THE DGZ IS CLOSE ENOUGH TO THE DGZ WHICH SHOULD ALLOW FOR SOME HELP WITH ACCUMS. THIS PART OF THE EVENT WILL HELP THE NW CORNER OF THE CWFA SEE THE HIGHEST ACCUMS DURING THE EVENT. SNOW IS EXPECTED TO PICK UP EVERYWHERE THIS EVENING WITH THE HEAVIEST SNOW ONCE AGAIN OVER THE WRN HALF OF THE CWFA WHERE LAKE ENHANCEMENT WILL CONTINUE. WE WILL SEE THE COLD FRONT APPROACHING THIS EVENING...AND THE THE CWFA WILL BE PLACED UNDER THE LFQ OF THE UPPER JET DIVING IN WHICH WILL HELP ON A SYNOPTIC SCALE. BLOWING AND DRIFTING WILL CONTINUE INTO TONIGHT...HOWEVER THE WINDS AND GUST POTENTIAL WILL BE DIMINISHING AS THE CORE OF WINDS AHEAD OF THE FRONT MOVES OUT OF THE AREA. THE SNOW WITH THE SYNOPTIC PORTION OF THE SYSTEM WILL MOVE OUT OF THE CWFA BY 12Z SAT...LEAVING LAKE EFFECT IN ITS WAKE. THE UPPER JET WILL BE WELL SOUTH OF THE AREA AT THIS TIME...ALLOWING FOR DECENT INVERSION HTS/MOISTURE/INSTABILITY TO BE IN PLACE ACROSS THE AREA. THE FAVORED AREAS FOR LAKE EFFECT WILL BE ACROSS THE NW AND SW PORTIONS OF THE CWFA WITH MEAN NW LOW LEVEL FLOW EXPECTED. LAKE EFFECT WILL THEN GRADUALLY DIMINISH SAT NIGHT AS THE UPPER JET LIFTS NORTH AND WE SEE SHORT WAVE RIDGING BUILD OVERHEAD. SAT NIGHT COULD BE A COLD NIGHT INLAND WHERE LAKE EFFECT CLOUDS WILL BE LIMITED. .LONG TERM...(SUNDAY THROUGH THURSDAY) ISSUED AT 324 AM EST FRI JAN 24 2014 MORE HIGH IMPACT/HAZARDOUS WINTER WEATHER IS LIKELY SUNDAY THROUGH TUESDAY WITH ADDITIONAL ACCUMULATING SNOW...BLOWING/DRIFTING SNOW....AND WIND CHILL TEMPERATURES WELL BELOW ZERO. SCHOOL/BUSINESS CLOSURES ARE A REAL POSSIBILITY MONDAY INTO TUESDAY ESPECIALLY FOR THE LAKESHORE COUNTIES WHERE FREQUENT WHITEOUT CONDITIONS AND TREACHEROUS TRAVEL APPEAR LIKELY AGAIN. THE NEXT CLIPPER DIVES SOUTHEAST THROUGH THE GRTLKS REGION ON SUNDAY AND SUNDAY NIGHT AND MAY BRING WIDESPREAD 2-4 INCH ACCUMULATIONS. HOWEVER CONFIDENCE ON THE EXACT TRACK OF THIS SYSTEM AND PLACEMENT/COVERAGE OF HIGHEST SYNOPTIC SNOW AMOUNTS ARE NOT PARTICULARLY HIGH AT THIS POINT. CONFIDENCE IS HIGH HOWEVER IN ANOTHER SIGNIFICANT INTRUSION OF BITTER COLD ARCTIC AIR AND LAKE EFFECT SNOW/BLOWING SNOW IN THE WAKE OF THE SYSTEM MONDAY INTO TUESDAY. THE AIR FOR EARLY NEXT WEEK WILL RIVAL THAT OF JANUARY 6-7 WHICH IRONICALLY WAS ALSO A MONDAY/TUESDAY EVENT. FINE SNOWFLAKE SIZE WILL LIMIT SNOW ACCUMULATIONS ALONG/WEST OF HIGHWAY 131 BUT WILL STILL RESULT IN POOR VISIBILITIES AND ICY ROAD CONDITIONS. TEMPERATURES SHOULD MODERATE INTO THE TEENS WEDNESDAY AND THURSDAY AS THE CORE OF THE COLDEST AIR LIFTS OUT... BUT MORE LAKE EFFECT SNOW IS LIKELY AS CYCLONIC WEST/SOUTHWEST FLOW PERSISTS. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON) ISSUED AT 1240 PM EST FRI JAN 24 2014 STRONG WINDS WILL CREATE BLOWING SNOW THIS AFTERNOON. SNOW WILL ALSO FALL AT KMKG/KGRR AND TO A LESSER EXTENT AT THE OTHER TAF SITES. VSBYS WILL BE LOWEST AT KMKG. HOWEVER...THERE LOOKS TO BE A LULL FROM LATE THIS AFTERNOON THROUGH MID EVENING BEFORE ANOTHER AREA OF LOW PRESSURE MOVES SOUTH OVER LAKE MICHIGAN. CIGS/VSBYS WILL FALL MID EVENING AND REMAIN THAT WAY OVERNIGHT. && .MARINE... ISSUED AT 327 PM EST THU JAN 23 2014 LITTLE QUESTION ON THE GALE WINDS FRIDAY BUT WHAT I THROUGH WE WOULD ALSO NEED WAS A FREEZING SPRAY WARNING SO I ADD THAT TO THE HEADLINE MIX IN THE NEAR SHORE PRODUCTS. && .HYDROLOGY... ISSUED AT 135 PM EST THU JAN 23 2014 RIVERS LEVELS ARE STEADY OR SLOWLY FALLING ACROSS THE AREA. STABLE ICE DEVELOPMENT WILL CONTINUE DUE TO A PROLONGED PERIOD OF COLD WEATHER. THE ICE JAM THREAT IS LOW AND THERE IS NO CURRENT INDICATIONS OF ANY ICE JAMS ON THE RIVER NETWORK. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...WINTER STORM WARNING UNTIL 7 AM EST SATURDAY FOR MIZ037-038-043- 044-050-056-057-064-065-071-072. WINTER WEATHER ADVISORY UNTIL 7 AM EST SATURDAY FOR MIZ039-040- 045-046-051-052-058-059-066-067-073-074. LM...HEAVY FREEZING SPRAY WARNING UNTIL 10 PM EST THIS EVENING FOR LMZ844>849. GALE WARNING UNTIL 10 PM EST THIS EVENING FOR LMZ844>849. && $$ UPDATE...WDM SYNOPSIS...NJJ SHORT TERM...NJJ LONG TERM...MEADE AVIATION...93 HYDROLOGY...63 MARINE...WDM
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1010 AM EST FRI JAN 24 2014 LATEST UPDATE... UPDATE .SYNOPSIS... ISSUED AT 324 AM EST FRI JAN 24 2014 CONDITIONS WILL GRADUALLY DETERIORATE THROUGH THE DAY TODAY ACROSS THE AREA. WINDS WILL INCREASE THIS MORNING WHERE WIND GUSTS OF 40 MPH OR MORE WILL BECOME LIKELY. THIS WIND IS EXPECTED TO PRODUCE BLOWING AND DRIFTING SNOW WITH RECENT SNOW THAT HAS FALLEN ACROSS THE AREA. THE BLOWING AND DRIFTING WILL BECOME WORSE THIS AFTERNOON AS ADDITIONAL SNOW DEVELOPS FROM NORTH TO SOUTH. SNOW WILL CONTINUE INTO TONIGHT BEFORE IT BECOMES MORE LOCALIZED LAKE EFFECT ON SATURDAY. ANOTHER SYSTEM WILL MOVE INTO THE AREA FOR THE DAY ON SUNDAY AND SUNDAY NIGHT. THIS WILL BRING ANOTHER ROUND OF SNOW TO THE AREA ALONG WITH MORE WIND AND COLD AIR. THIS COULD PRODUCE A GOOD DEAL OF IMPACT TO THE AREA WITH BLOWING AND DRIFTING SNOW POSSIBLE. MORE COLD AIR AND LAKE EFFECT WILL RULE INTO MUCH OF NEXT WEEK. && .UPDATE... ISSUED AT 1008 AM EST FRI JAN 24 2014 OUR CURRENT FORECAST IS ON TRACK. THE LAKE ENHANCED SOUTHWEST FLOW SNOW EVENT IS STARTING TO INCREASE AND SHOULD BE GOING STRONG BETWEEN 1 PM AND 5 PM. THERE MAY BE A SORT OF LULL FOR A FEW HOURS THEN THE MORE SYNOPTIC PART OF THE STORM KICKS IN AROUND 7 PM AND SHOULD GO TILL AROUND 6 AM. IT DURING THAT TIME MOST OF THE SNOWFALL WILL OCCUR. AS OF 10 AM WE HAVE WIND CHILLS OF 15 TO 25 BELOW OVER MOST OF OUR CENTRAL AND SOUTHERN CWA AND BETWEEN 5 AND 15 BELOW NORTH OF THERE. AS THE WIND INCREASES TEMPERATURES WILL ALSO RISE SO I EXPECT OVERALL THE WIND CHILLS TO WARM SOME...BEING IN THE 0 TO 10 BELOW RANGE BY LATE AFTERNOON. THE LATEST RAP AND NAM SHOW THE LAKE SHORE COUNTIES WILL HAVE 50 TO 55 KNOTS IN THE MIXED LAYER (3000 FT IN DEPTH) FROM 1 PM TILL 5 PM THIS AFTERNOON. EVEN WITH GUSTS OF 25-30 MPH RANGE MKG...GRR AND BIV HAVE VISIBILITIES UNDER 3 MILES IN SNOW AND BLOWING SNOW. ONCE THE SNOW RATES INCREASE BY EARLY AFTERNOON WITH WINDS GUSTING NEAR 40 MPH WE WILL BE SEEING NEAR BLIZZARD CONDITIONS. WE WILL HAVE TO MONITOR THIS TO SEE IF WE NEED TO UPGRADE TO BLIZZARD WARNING... HOWEVER AT THIS TIME IT STILL SEEMS TO ME WE CAN GO AHEAD WITH THE WINTER STORM WARNINGS/ADVISORIES AS THEY ARE. ONE OTHER ISSUE TO ADDRESS LATER IS THE LAKE EFFECT BEHIND THE STORM SATURDAY. I COULD SEE EXPANDED THE WARNING INTO SATURDAY AFTERNOON FOR THE COUNTIES ALONG AND WEST OF US-131. && .SHORT TERM...(TODAY THROUGH SATURDAY NIGHT) ISSUED AT 324 AM EST FRI JAN 24 2014 OBVIOUSLY THE MAIN FOCUS OF THE SHORT TERM IS THE EVENT EXPECTED FOR TODAY INTO THE FIRST PORTION OF SATURDAY WITH THE STRONGER SYSTEM EXPECTED TO DROP THROUGH THE AREA. WE WILL NOT BE MAKING ANY CHANGES TO THE HEADLINES WITH THIS FCST PACKAGE. WE HAVE INCREASED SNOW TOTALS A BIT ACROSS THE NRN PORTION OF THE WARNING AREA AS CONDITIONS LOOK A BIT MORE FAVORABLE FOR BETTER ACCUMULATIONS. THE RELATIVE CALM BEFORE THE STORM IS CURRENTLY MOVING IN THIS MORNING. RESIDUAL LAKE EFFECT HAS DIMINISHED TO FLURRIES AS THE UPPER JET IS SHIFTING OUT OF THE AREA AND SHORT WAVE RIDGING BUILDS IN. CLOUDS HOLDING IN THUS FAR HAVE KEPT TEMPS AND RESULTING WIND CHILLS IN CHECK. WE DO EXPECT WIND CHILLS TO DROP OVER THE NEXT FEW HOURS AS CLEARING FROM THE S WILL MOVE IN ACROSS THE SE WITH THE FLOW GOING SW. WINDS WILL START PICKING UP AND DRIVE THE WIND CHILLS DOWN THIS MORNING. WINDS WILL ONLY INCREASE THIS MORNING...AND REALLY GET CRANKING AROUND MID MORNING. THE STRONGEST WINDS LOOK TO OCCUR CENTERED AROUND 18Z +/- A COUPLE OF HOURS DEPENDING ON THE LOCATION. WE CONTINUE TO EXPECT WIND GUSTS UP TO 40-45 MPH WITH SOME HIGHER GUSTS ALONG THE IMMEDIATE LAKESHORE. THESE WINDS WILL BE INCREASING WHILE LITTLE TO NO SNOW IS FALLING THIS MORNING. THE WINDS WILL HAVE THE FRESH SNOW FROM THE LAST COUPLE OF DAYS TO PRODUCE BLOWING AND DRIFTING. HOW MUCH REDUCTION IN VISIBILITY BEFORE ADDITIONAL SNOW STARTS FALLING IS UNCERTAIN. THIS IS ONE REASON WE ARE HOLDING OFF ON A POSSIBLE UPGRADE TO A BLIZZARD WARNING. SNOW WILL DEVELOP UP NORTH WITH THE BETTER WINDS STILL IN PLACE...SO THE WARNING AREA UP NORTH WILL NEED TO BE MONITORED A BIT CLOSER. THE WORST BLOWING AND DRIFTING SNOW WILL OCCUR WHILE THE WINDS ARE STILL UP THIS AFTERNOON AND AS THE SNOW GRADUALLY DEVELOPS TO THE SOUTH. THIS SNOW PORTION OF THE EVENT WILL BE A COMBINATION OF ISENTROPIC ASCENT AND LAKE ENHANCEMENT WITH DELTA T/S EXPECTED TO BE IN THE MIDDLE TEENS C BY THAT TIME. MODELS ARE INDICATING SOME FAIRLY ROBUST CONVERGENCE ACROSS THE NW CORNER OF THE CWFA LIKELY DUE TO THE WINDS COMING OFF OF THE LAKE AND DUE TO THE FLOW AND THE CONTOUR OF THE COAST. THIS WILL ALLOW FOR SOME LOCALLY HEAVIER BANDS SIMILAR TO THE EVENT EARLIER THIS WEEK. THE DGZ IS CLOSE ENOUGH TO THE DGZ WHICH SHOULD ALLOW FOR SOME HELP WITH ACCUMS. THIS PART OF THE EVENT WILL HELP THE NW CORNER OF THE CWFA SEE THE HIGHEST ACCUMS DURING THE EVENT. SNOW IS EXPECTED TO PICK UP EVERYWHERE THIS EVENING WITH THE HEAVIEST SNOW ONCE AGAIN OVER THE WRN HALF OF THE CWFA WHERE LAKE ENHANCEMENT WILL CONTINUE. WE WILL SEE THE COLD FRONT APPROACHING THIS EVENING...AND THE THE CWFA WILL BE PLACED UNDER THE LFQ OF THE UPPER JET DIVING IN WHICH WILL HELP ON A SYNOPTIC SCALE. BLOWING AND DRIFTING WILL CONTINUE INTO TONIGHT...HOWEVER THE WINDS AND GUST POTENTIAL WILL BE DIMINISHING AS THE CORE OF WINDS AHEAD OF THE FRONT MOVES OUT OF THE AREA. THE SNOW WITH THE SYNOPTIC PORTION OF THE SYSTEM WILL MOVE OUT OF THE CWFA BY 12Z SAT...LEAVING LAKE EFFECT IN ITS WAKE. THE UPPER JET WILL BE WELL SOUTH OF THE AREA AT THIS TIME...ALLOWING FOR DECENT INVERSION HTS/MOISTURE/INSTABILITY TO BE IN PLACE ACROSS THE AREA. THE FAVORED AREAS FOR LAKE EFFECT WILL BE ACROSS THE NW AND SW PORTIONS OF THE CWFA WITH MEAN NW LOW LEVEL FLOW EXPECTED. LAKE EFFECT WILL THEN GRADUALLY DIMINISH SAT NIGHT AS THE UPPER JET LIFTS NORTH AND WE SEE SHORT WAVE RIDGING BUILD OVERHEAD. SAT NIGHT COULD BE A COLD NIGHT INLAND WHERE LAKE EFFECT CLOUDS WILL BE LIMITED. .LONG TERM...(SUNDAY THROUGH THURSDAY) ISSUED AT 324 AM EST FRI JAN 24 2014 MORE HIGH IMPACT/HAZARDOUS WINTER WEATHER IS LIKELY SUNDAY THROUGH TUESDAY WITH ADDITIONAL ACCUMULATING SNOW...BLOWING/DRIFTING SNOW....AND WIND CHILL TEMPERATURES WELL BELOW ZERO. SCHOOL/BUSINESS CLOSURES ARE A REAL POSSIBILITY MONDAY INTO TUESDAY ESPECIALLY FOR THE LAKESHORE COUNTIES WHERE FREQUENT WHITEOUT CONDITIONS AND TREACHEROUS TRAVEL APPEAR LIKELY AGAIN. THE NEXT CLIPPER DIVES SOUTHEAST THROUGH THE GRTLKS REGION ON SUNDAY AND SUNDAY NIGHT AND MAY BRING WIDESPREAD 2-4 INCH ACCUMULATIONS. HOWEVER CONFIDENCE ON THE EXACT TRACK OF THIS SYSTEM AND PLACEMENT/COVERAGE OF HIGHEST SYNOPTIC SNOW AMOUNTS ARE NOT PARTICULARLY HIGH AT THIS POINT. CONFIDENCE IS HIGH HOWEVER IN ANOTHER SIGNIFICANT INTRUSION OF BITTER COLD ARCTIC AIR AND LAKE EFFECT SNOW/BLOWING SNOW IN THE WAKE OF THE SYSTEM MONDAY INTO TUESDAY. THE AIR FOR EARLY NEXT WEEK WILL RIVAL THAT OF JANUARY 6-7 WHICH IRONICALLY WAS ALSO A MONDAY/TUESDAY EVENT. FINE SNOWFLAKE SIZE WILL LIMIT SNOW ACCUMULATIONS ALONG/WEST OF HIGHWAY 131 BUT WILL STILL RESULT IN POOR VISIBILITIES AND ICY ROAD CONDITIONS. TEMPERATURES SHOULD MODERATE INTO THE TEENS WEDNESDAY AND THURSDAY AS THE CORE OF THE COLDEST AIR LIFTS OUT... BUT MORE LAKE EFFECT SNOW IS LIKELY AS CYCLONIC WEST/SOUTHWEST FLOW PERSISTS. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING) ISSUED AT 700 AM EST FRI JAN 24 2014 THE MAIN AVIATION ISSUE TODAY WILL BE THE STRONG WINDS. WINDS BLOWING FROM THE SOUTHWEST WILL REACH SUSTAINED SPEEDS OF 23 TO 28 KNOTS BY MID TO LATE MORNING WITH GUSTS TO AROUND 40 KNOTS LIKELY. THE WINDS ARE EXPECTED TO DIMINISH SOMEWHAT THIS EVENING BUT GUSTS TO 30 KNOTS ARE STILL LIKELY TONIGHT. SNOW SHOWERS TODAY SHOULD BE RESTRICTED TO MAINLY JUST THE MKG AND GRR TERMINALS... WHERE AN INCREASE IN SNOW AND BLOWING SNOW IS LIKELY THIS AFTERNOON. THIS SHOULD EVENTUALLY LEAD TO PERSISTENT IFR CONDITIONS AT MKG AND GRR. MEANWHILE SOUTH AND EAST OF GRR THE BULK OF THE SNOW IS EXPECTED TO HOLD OFF UNTIL AFTER 22Z WHICH SHOULD RESULT IN VFR CONDITIONS FOR MUCH OF TODAY. HOWEVER THE STRONG WINDS COULD LEAD TO OCCASIONAL BLOWING SNOW AND REDUCTIONS IN VSBYS. WIDESPREAD IFR/LIFR VSBYS IN SNOW EXPECTED FOR ALL OF THE TERMINAL TONIGHT... WITH THE WORST CONDITIONS AT MKG AND GRR. && .MARINE... ISSUED AT 327 PM EST THU JAN 23 2014 LITTLE QUESTION ON THE GALE WINDS FRIDAY BUT WHAT I THROUGH WE WOULD ALSO NEED WAS A FREEZING SPRAY WARNING SO I ADD THAT TO THE HEADLINE MIX IN THE NEAR SHORE PRODUCTS. && .HYDROLOGY... ISSUED AT 135 PM EST THU JAN 23 2014 RIVERS LEVELS ARE STEADY OR SLOWLY FALLING ACROSS THE AREA. STABLE ICE DEVELOPMENT WILL CONTINUE DUE TO A PROLONGED PERIOD OF COLD WEATHER. THE ICE JAM THREAT IS LOW AND THERE IS NO CURRENT INDICATIONS OF ANY ICE JAMS ON THE RIVER NETWORK. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...WINTER STORM WARNING UNTIL 7 AM EST SATURDAY FOR MIZ037-038-043- 044-050-056-057-064-065-071-072. WINTER WEATHER ADVISORY UNTIL 7 AM EST SATURDAY FOR MIZ039-040- 045-046-051-052-058-059-066-067-073-074. LM...HEAVY FREEZING SPRAY WARNING UNTIL 10 PM EST THIS EVENING FOR LMZ844>849. GALE WARNING UNTIL 10 PM EST THIS EVENING FOR LMZ844>849. && $$ UPDATE...WDM SYNOPSIS...NJJ SHORT TERM...NJJ LONG TERM...MEADE AVIATION...MEADE HYDROLOGY...63 MARINE...WDM
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
608 AM CST FRI JAN 24 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 407 AM CST FRI JAN 24 2014 VERY BUSY SHORT TERM PERIOD EXPECTED...WITH TWO ROUNDS OF PRECIP EXPECTED THIS MORNING AND AGAIN THIS AFTERNOON/EVENING...WITH STRONG NW WINDS RETURNING THIS EVENING AND OVERNIGHT WITH THE POTENTIAL FOR BLOWING SNOW ISSUES. STRONG WAA IN PROGRESS THIS MORNING...AS EVIDENCE BY TEMPERATURES THAT HAVE BE STEADILY RISING 2 TO 4 DEGREES PER HOUR FOR MOST LOCATIONS SINCE MIDNIGHT AS GUSTY SOUTHWEST WINDS HAVE DEVELOPED OUT AHEAD OF A WARM FRONT THAT IS DROPPING SE FROM NODAK/NW MN. ALTHOUGH WE HAVE SEEN WINDS GUSTING TO NEAR 50 MPH AT TIMES IN WRN MN...WE HAVE NOT SEEN ANY VISIBILITY RESTRICTIONS DUE TO BLOWING SNOW. THIS IS DUE TO THE FACT THAT ANY BLOWABLE SNOW WAS BLOWN OUT OF THE AREA WITH THE BLIZZARD WEDNESDAY NIGHT. WITH NO BLOWING SNOW IMPACTS OCCURRING...HAVE CANCELLED THE WINTER WEATHER ADVISORY...GOOD CALL BY EARLIER SHIFTS NOT TO GO WITH ANOTHER BLIZZARD WARNING FOR LAST NIGHT. 24 HOUR TEMP CHANGES ACROSS THE DAKOTAS AND SRN CANADA HAVE BEEN RUNNING BETWEEN 30 AND 45 DEGREES WARMER OVERNIGHT...AND THIS TREND WILL CONTINUE TODAY INTO THE MPX CWA FOR THE AFTERNOON. HOWEVER...WITH AFTERNOON HIGHS THURSDAY ONLY 2 TO 8 DEGS BELOW ZERO...EVEN A 24 HOUR TEMP CHANGE OF 40 DEGREES WOULD NET YOU HIGHS OF 35 TO 40...WHICH IS WHAT IS CURRENTLY FORECAST FOR MUCH OF THE AREA ALONG AND SW OF THE I-94 CORRIDOR. THESE FORECAST HIGHS MATCH UP WELL WITH WHAT THE GEM AND ECMWF BIAS CORRECTED HIGHS HAVE FOR TODAY...WHICH ARE THE PIECES OF GUIDANCE THAT HAVE SHOWN THE BEST VERIFICATION THIS WINTER WHEN WE HAVE SEEN OUR OCCASIONAL WARM PUFFS OF AIR. THE FIRST ROUND OF SNOW IS MOVING THROUGH THIS MORNING OUT AHEAD OF THE WARM FRONT DROPPING SOUTHEAST. WE HAVE SEEN A VERY NARROW BAND OF SNOW DEVELOP WITH PRETTY HEALTHY SNOWFALL RATES /AS EVIDENCED VISIBILITIES DIPPING DOWN TO 3/4SM/...BUT SNOW HAS BEEN ONLY LASTING 1 TO 2 HOURS...WITH A QUICK HALF INCH OR SO OF SNOW BEING PICKED UP AS THE BAND WORKS THROUGH. THE RAP/HRRR HAVE HAD A GOOD HANDEL ON THE BAND THIS MORNING...SO USED THOSE MODELS TO QUICKLY MOVE THIS NARROW BAND THROUGH THE MPX CWA THIS MORNING. UNFORTUNATELY FOR THE TWIN CITIES...THIS SNOW BAND IS STILL IN STORE TO IMPACT THE METRO BETWEEN 5 AND 7 THIS MORNING...SO WILL LIKELY LEAD TO A SLOW MORNING COMMUTE. ROUND TWO OF SNOW TODAY WILL COME ABOUT 8 HOURS AFTER ROUND ONE AS LIFT AND MOISTURE INCREASE HEAD OF ANOTHER ARCTIC COLD FRONT THAT WILL BE DROPPING SOUTH ACROSS THE MPX AREA BETWEEN 6PM AND MIDNIGHT. HI-RES MODELS IN GOOD AGREEMENT WITH LIGHT PRECIP BLOSSOMING ACROSS CENTRAL MN AROUND 21Z AND DROPPING SOUTH THROUGH THE EVENING WITH THE COLD FRONT. THERE IS A REASON I MENTION PRECIP AND NOT SNOW. THE ECMWF CONTINUES TO SHOW 925 MB TEMPS IN EXCESS OF 0Z COMING UP A LITTLE NORTH OF THE MN RIVER AND WITH AFTERNOON HIGHS FOR THE SW CWA EXPECTED TO CLIMB INTO THE MID/UPPER 30S...IT MEANS P-TYPE IS AT ISSUE. HAVE IT WARM ENOUGH TO GET ALL RAIN FOR MOST OF LAC QUI PARLE AND WRN YELLOW MEDICINE COUNTIES...WITH A RA/SN MIX OUT TO THE MN RIVER. IT WILL BE COLD ENOUGH TO MAINTAIN SNOW EVERYWHERE ELSE...BUT QPF AMOUNTS AGAIN LOOK LIGHT...WITH ANOTHER HALF TO ONE INCH OF SNOW POSSIBLE. UNFORTUNATELY AGAIN FOR THE TWIN CITIES...THIS LIGHT SNOW LOOKS TO START JUST IN TIME FOR THE EVENING COMMUTE...THOUGH HOPEFULLY TEMPERATURE UP CLOSE TO FREEZING WILL KEEP THINGS FLOWING A LITTLE FASTER. TONIGHT BEHIND THE COLD FRONT...WINDS WILL INCREASE AGAIN...WITH NAM BUFR SOUNDING SHOWING TOP OF THE CHANNEL MIXING AGAIN GOING OVER 40 KTS ACROSS MOST OF THE MN CWA AS CAA CREATES DEEP AND STEEP LOW LEVEL LAPSE RATES. CERTAINLY WINDS LIKE THIS ARE STRONG ENOUGH TO CREATE BLOWING SNOW ISSUES...BUT DECIDED AGAINST ISSUING ANY HEADLINES FOR 3 REASONS. 1...AS WE HAVE SEEN BEFORE THIS WINTER...THESE WARM TEMPERATURES TODAY WILL MOISTEN UP THE SNOWPACK...MAKING IT CONSIDERABLY LESS BLOWABLE. 2...AS WE SAW OVERNIGHT...THE BLIZZARD WEDNESDAY BLEW CLEAR MOST OF THE SNOW THAT COULD BE BLOWN AROUND AND WHAT WE ARE GETTING TODAY AND THIS EVENING WILL NOT BE THE 25+:1 TYPE STUFF. 3...WITH A POTENTIALLY MUCH MORE SIGNIFICANT WEATHER SITUATION SETTING UP ON SUNDAY...DID NOT WANT TONIGHT TO LIMIT THE FOCUS ON THAT. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 407 AM CST FRI JAN 24 2014 CONFIDENCE REMAINS VERY HIGH FOR A BLIZZARD ACROSS MUCH OF OUR MN CWA SUNDAY AFTERNOON AND SUNDAY NIGHT. MODEL CONSISTENCY REMAINS HIGH ON A DEEPENING CLIPPER MOVING FROM ND TO SOUTHERN WI SATURDAY NIGHT THROUGH SUNDAY. LIKELY TO CATEGORICAL POPS FOR SNOW IN PLACE SATURDAY NIGHT AHEAD OF THE CLIPPER WITH 2-4 INCHES OF SNOW LIKELY CWA WIDE BY SUNDAY MORNING. THE ONE REAL INTERESTING CHANGE TONIGHT IS THAT THE ECMWF IS NOW GENERATING A SECONDARY SURFACE LOW ALONG THE ARCTIC BOUNDARY IN SOUTHERN MN SUNDAY AFTERNOON. THIS IS A REFLECTION OF A 700 MB LOW MOVING THROUGH. THIS FEATURE COUPLED WITH ELEVATED INSTABILITY IN THE DENDRITIC ZONE WILL RESULT IN SNOW SHOWERS...ADDING MORE FUEL TO THE FIRE. POPS WERE RAISED INTO THE LIKELY CATEGORY FOR JUST ABOUT THE ENTIRE CWA ON SUNDAY. THE GRIDS ARE SET FOR A BLIZZARD WITH SUSTAINED WINDS OF 35 MPH...WITH GUSTS NEAR 55 MPH...IN THE MN RIVER VALLEY. THE ECMWF REMAINS THE HIGHEST ON SUSTAINED WINDS WITH 40 MPH STRETCHING FROM MONTEVIDEO TO ALBERT LEA BY SUNDAY EVENING. COLLABORATION WITH OUR WESTERN NEIGHBORS WAS TO HOLD OFF ON SUNDAY AT THIS POINT DUE TO WATCHES BEING ISSUED FOR TONIGHT FOR POTENTIAL BLIZZARD CONDITIONS WEST AND NORTH. NO CHANGE FOR EARLY NEXT WEEK AS VERY COLD ARCTIC AIR POURS INTO THE REGION FROM SUNDAY NIGHT THROUGH WEDNESDAY. WINDS WILL REMAIN BRISK MONDAY INTO TUESDAY AS THE HIGH PRESSURE SYSTEM REMAINS PARKED OVER THE DAKOTAS. LOWS MONDAY AND TUESDAY MORNINGS WILL BE FROM 15 TO 30 BELOW ZERO ACROSS THE FORECAST AREA. HIGHS ON MONDAY WILL ONLY BE FROM 10 TO 15 BELOW ZERO. FACTOR IN THAT BRISK NORTHWEST WIND AND WIND CHILL VALUES FROM LATE SUNDAY NIGHT THROUGH TUESDAY MORNING ARE 40 TO 50 BELOW ZERO. HENCE... WIND CHILL WARNINGS WILL BE NEEDED. WIND CHILL ADVISORY CRITERIA IS THEN MET FROM TUESDAY AFTERNOON THROUGH WEDNESDAY MORNING. A VERY BRUTAL PERIOD AHEAD. SOME MODERATION IN TEMPERATURE IS LIKELY FROM WEDNESDAY INTO THURSDAY AS YET ANOTHER CLIPPER APPROACHES. SMALL CHANCES OF SNOW ARE IN FOR THESE PERIODS. THE ECMWF IS ADAMANT THAT MORE ARCTIC AIR WILL SURGE IN FOR LATE IN THE WEEK/WEEKEND. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING) ISSUED AT 546 AM CST FRI JAN 24 2014 BAND OF SNOW MOVING THROUGH WILL MAINLY IMPACT WRN WI...AS SNOW REPORTS HAVE BEEN HARD TO COME BY WEST OF THE TWIN CITIES. EXPECT A LONG BREAK IN SNOW UNTIL THIS AFTERNOON WHEN THE HRRR ALONG WITH OTHER HI-RES MODELS SHOW PRECIP BREAKING OUT AGAIN ACROSS CENTRAL MN AROUND 20Z OUT AHEAD OF A COLD FRONT THAT WILL SINK SOUTH ACROSS THE AREA THIS EVENING. 06Z TAFS HAD THIS TRENDED WELL...AND ONLY REALLY DELAYED SNOW ONSET BY AN HOUR. CIGS ARE A BIT PROBLEMATIC THIS MORNING...AS STRONG SW WINDS ARE ALSO BRING WITH DRIER LOW LEVEL AIR. RAP WOULD SAY MVFR CIGS REMAIN TODAY NORTH OF I-94...WHILE THE NAM JUST TAKES A BAND ACROSS THE AREA WITH THE SNOW. GIVEN EXNTENSIVE MVFR CIGS ACROSS NRN MN...WENT WITH THE IDEA OF THE RAP...WITH THE NRN MN CIGS SLIDING SE INTO WRN WI TODAY. HAVE TEMPO MVFR CONDS IN THE MORNING FOR THE I-94 TAFS IN MN...WITH A PROLONGED PERIOD OF VFR CIGS EXPECTED BEFORE LIGHT SNOW STARTS TO BLOSSOM THIS AFTERNOON. BEHIND THE COLD FRONT...WILL SEE ANOTHER ROUND OF STRONG NW WINDS DEVELOP. SHOULD SEE A FEW HOURS OF GUSTS IN EXCESS OF 30 KTS. AS FOR BLSN...COMBINATION OF BLOWABLE SNOW BLOWN AWAY ON WEDNESDAY AND MILDER TEMPS EXPECTED TODAY SHOULD LIMIT THE AM0UNT OF BLSN WE SEE...SO HAVE PULLED BACK ON BLSN MENTION IN TAFS. KMSP...LOOKING LIKE MSP WILL LARGELY MISS OUT ON SNOW THIS MORNING GIVEN LACK OF SNOW OBS MAKING INTO THE TWIN CITES. MSP WILL ALSO BE ON THE EDGE OF MVFR CIGS THIS MORNING INTO THE AFTERNOON. COULD SEE CIGS DROP DOWN TO AROUND 020 FOR A TIME THIS MORNING INTO THE AFTERNOON. CHANCE FOR SNOW THIS AFTERNOON AND EVENING LOOKS MUCH BETTER...WITH STRONG AGREEMENT ON ITS RETURN IN ALL GUIDANCE. EXPECT A RAPID CLEARING THIS AS NW WINDS GUST TO AROUND 30 KTS BETWEEN 3Z AND 8Z. /OUTLOOK FOR KMSP/ SAT...VFR. MVFR/IFR -SN OVERNIGHT. WIND NW 10-15KTS BCMG W/SW LATE. SUN...MVFR/IFR WITH SN. WINDS S BECOMING NW AT 20G35KTS. MON...VFR. WINDS NW AT 10G15KTS. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. && $$ SHORT TERM...MPG LONG TERM...RAH AVIATION...MPG
AREA FORECAST DISCUSSION...UPDATED
NWS ST LOUIS MO
1201 PM CST Fri Jan 24 2014 .UPDATE: Issued at 1141 AM CST Fri Jan 24 2014 Going forecasts still looking pretty good for this afternoon. Strong winds and low RH values are the primary concerns for the FA, and area/timing of going headlines still appear to be on the mark. Only real concern regarding sensible weather trends is temperatures, which appear to be warming slower than initially expected. Given the depth of the cold air that the mixing is trying to erode we may be a bit too warm on afternoon max temps, but given very favorable synoptic setup for a pronounced warmup am hesitant to make too much of a downward adjustment at this time. Truett && .SHORT TERM: (Through Late This Afternoon) Issued at 330 AM CST Fri Jan 24 2014 The large Arctic high will continue to sink southward away from the region today while the next frontal system begins driving southward into the northern Plains. In between the surface pressure gradient will tighten up as will the height field, resulting in rather strong winds through the lower trop. The combination of this along with mixing will produce strong and gusty southwest winds. Both MOS values and wind gusts from the HRRR and RAP suggest winds will meet advisory criteria across central and northeast Missouri into west central Illinois with wind gusts of 40 kts possible. This regime is also favorable for a good warm-up even with the very cold start, and have highs above the MOS guidance. Glass .LONG TERM: (Tonight through Thursday) Issued at 330 AM CST Fri Jan 24 2014 A nw flow shortwave and attendant ULJ will dig into the area tonight sending another cold front through the region. As has been the case recently, strong and gusty northwest winds will accompany the front. Large scale ascent associated with the shortwave appears sufficient to produce an area of light snow across northeast Missouri into western Illinois. Currently it looks like the St. Louis region will be on the western fringe of the snow field. I have bumped up pops in the high chance to likely category within the aforementioned zone, and anticipate amounts from a dusting to less than an inch. We remain in cyclonic flow and northwest winds on Saturday with temperatures expected to remain below average. The temperature see-saw then continues on Sunday as the weak high pressure ridge departs quickly on Saturday night and we are well into low-level warm advection just after midnight. Strong warm advection on Sunday and gusty southwest-west winds once again suggest a good warm-up with highs getting well above normal. Enjoy the "warmth" because it is all downhill after Sunday. The next formidable Arctic front/blast comes roaring into the region on Sunday night and the airmass with this front is the coldest since the early January Arctic outbreak. A large full latitude longwave trof will continue to dominate central and eastern NOAM through the middle of next week keeping very cold conditions locked in across the region. The models are finally showing signs this blocky cold pattern breaking down and by early February suggest a negative phase of the PNA pattern will become established. Glass && .AVIATION: (For the 18z TAFs through 18z Saturday Afternoon) Issued at 1141 AM CST Fri Jan 24 2014 Strong surface winds will highlight this TAF period...with intense SW winds this afternoon transitioning to the NW late tonight and Saturday morning with a passage of yet another fast moving cold front. Core of highest winds this afternoon should be along the COU/UIN corridor, with frequent gusts in the 30-35kt range. Cloud will be limited to the mid and high levels this afternoon (aoa 10kft), but will lower this evening as the cold front presses into the region. Believe much of this cloudiness will remain in the VFR cat (3-5kft), but areas of snow clipping the Mississippi River will produce briefly lower conditions (MVFR/IFR), primarily at UIN and just east of STL metro. Specifics for KSTL: Into the early evening forecast will be dominated by SW surface winds (210-230 degrees) gusting to near 30kts along with patches of mid and high level cloudiness. Winds will veer overnight as cold front moves in, which should also be accompanied by ceilings lowering to the 3-5kft range. Have continued mention of flurries for a few predawn hours, but latest short range guidance is suggesting that bulk of the snow...and the lowest conditions...will be occurring just northeast or east of STL. Truett && .FIRE WEATHER: Issued at 420 AM CST Fri Jan 24 2014 Although have made minor tweeks to winds, temps, and dewpoints/RH, timing and area of Red Flag Warning which covers central, east central and southeast Missouri still looks very good. If temperatures don`t warm as much as expected a few of the eastern fringe areas may not reach the critical RH below 25%, but at this point, but for reasons noted in short range AFD discussion no major adjustments made at this time. Truett && .LSX WATCHES/WARNINGS/ADVISORIES: MO...RED FLAG WARNING until 7 PM CST this evening FOR Audrain MO- Boone MO-Callaway MO-Cole MO-Crawford MO-Dent MO-Franklin MO-Gasconade MO-Iron MO-Jefferson MO-Lincoln MO-Madison MO- Moniteau MO-Monroe MO-Montgomery MO-Osage MO-Reynolds MO- St. Charles MO-St. Francois MO-St. Louis City MO-St. Louis MO-Ste. Genevieve MO-Warren MO-Washington MO. WIND ADVISORY until 6 PM CST this evening FOR Audrain MO-Boone MO-Callaway MO-Cole MO-Knox MO-Lewis MO-Marion MO-Moniteau MO-Monroe MO-Montgomery MO-Osage MO-Pike MO-Ralls MO-Shelby MO. IL...WIND ADVISORY until 6 PM CST this evening FOR Adams IL-Brown IL- Pike IL. && $$ WFO LSX
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
1152 AM CST Fri Jan 24 2014 .DISCUSSION... Issued at 358 AM CST FRI JAN 24 2014 Today: Primary focus will be on strong wind potential and critical fire danger (see FIRE WEATHER section below). For the umpteenth time this month, yet another strong mid level gyre will drop south from central Canada, replacing the arctic air with increasingly mild conditions. Surface pressures which started out at around 1044mb at 00Z, will crash to near 1014mb by 00Z this evening. Aches and pains alert! Incredible 30mb/24-hour pressure falls, coupled with 50-60 knot 925mb flow, will once again set the stage for very windy conditions across the region. As has been the case with the last several wind events, strong vertical mixing and downward momentum transfer will contribute to very strong gusts that will be well above what is "typically" expected for forecast sustained winds of 15 to 25 mph. Other than scattered mid cloud, ample sunshine should help realize nearly maximum gust potential, with the RAP and HRRR both suggesting widespread gusts exceeding 40 knots from late morning through mid afternoon, as the pressure wave pushes southeast. Have collaborated a wind advisory which will run from 10AM through 2PM across far NW MO/NE KS, and through 6PM across most of west central/central/northeast MO into far eastern Kansas. Despite the southwest winds, warm advection will lag quite a bit, with most of the diurnal temperature boost coming in the 11AM-3PM time frame. As a result, another very cold start expected this morning with wind chills in the -5 to -10F range as the kids head to the bus stop. Tonight-Saturday: Deep mixing will keep temperatures relatively mild tonight with lows running some 20 degrees warmer than this morning. A few flurries to a light dusting of snow could glance the far NE counties, but the bulk of any very minor accumulations should once again fall well east of the region as the strongest mid level ascent shifts into the Great Lakes and Ohio Valley. Weak cyclonic flow and cloud cover beneath and intense upper jet will lend to a challenging temperature forecast Saturday. High temperatures will range some 15-20 degrees from the upper 20s near Kirksville to the mid 40s across west central MO, and the gradient magnitude varies considerably among the 00Z models. Sunday-Sunday Night: Low level temps will steadily warm Saturday night and early Sunday ahead of the next arctic blast. 925mb temps could reach +10C, suggesting that temperatures will likely reach the low-mid 50s across all but far nrn MO before frontal passage late in the afternoon. Definitely the mildest day in the coming week. In a reversal of fortune so to speak, surface pressures will increase 30mb from 12Z Sunday to 12Z Monday, coincident with a strong arctic blast trailing yet another Canadian Clipper. Temperatures will plummet some 45 to 50 degrees from Sunday afternoon to Monday morning, and I would not be surprised to see wind gusts again in the 30-40 mph range Sunday evening. (Need to do some research as I cannot ever recall this magnitude of wind in January across Missouri). Monday-Thursday: See no change in the overall upper flow pattern to round out the end of the month. Above average confidence in little to no measurable precipitation, and above average confidence in much below normal temperatures Monday/Tuesday, then trending back toward normal Wednesday/Thursday ahead of the next closed low in the sequence dropping south through the Canadian Prairies. && .AVIATION...(For the 18Z TAFS through 18Z Saturday Afternoon) Issued at 1142 AM CST FRI JAN 24 2014 Gusty southwest winds will continue through the day around 20 to 30 kts with gusts approaching 35 to 40 kts at times. Although winds will gradually diminish through the evening to overnight hours expect winds to remain around 10 to 15 kts. There will be a gradual shift from SW to NW as a frontal passage comes through the area. By the end of the forecast period, expect winds to be out of the NW around 15 to 25 kts, likely increasing after this forecast period. There could be a brief period of MVFR stratus as the frontal passage occurs, but considering how uncertain the soundings look and the brief time it would occur, kept that period VFR for now, and will reassess as the front approaches. && .FIRE WEATHER... Issued at 358 AM CST FRI JAN 24 2014 Dangerous fire weather conditions are expected along and south of a St. Joseph to Carrollton to Moberly line from late morning through mid afternoon. Early morning observations show a very dry boundary layer in place with dew points in the single digits below zero. Very little moderate of this air mass is expected as temperatures steadily warm into the upper 30s to mid 40s this afternoon, yielding relative humidity values between 18 and 25%. The very dry air mass and 10-hour fuel stick moisture of 7-8% will contribute to a very volatile setup as southwest winds increase to 20 to 25 mph with gusts up to 45 mph. Given the potential for rapid grassland fire spread, a red flag warning remains in effect from 10AM through 8PM for the aforementioned areas. && .EAX WATCHES/WARNINGS/ADVISORIES... KS...RED FLAG WARNING until 8 PM CST this evening FOR KSZ025-057-060- 102>105. WIND ADVISORY until 6 PM CST this evening FOR KSZ057-060-103>105. WIND ADVISORY until 2 PM CST this afternoon FOR KSZ025-102. MO...RED FLAG WARNING until 8 PM CST this evening FOR MOZ020>025- 028>033-037>040-043>046-053-054. WIND ADVISORY until 6 PM CST this evening FOR MOZ008-017-021>025- 028>033-037>040-043>046-053-054. WIND ADVISORY until 2 PM CST this afternoon FOR MOZ001>007- 011>016-020. && $$ DISCUSSION...Bookbinder AVIATION...Leighton FIRE WEATHER...Bookbinder
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
546 AM CST Fri Jan 24 2014 .SHORT TERM: (Through Late This Afternoon) Issued at 330 AM CST Fri Jan 24 2014 The large Arctic high will continue to sink southward away from the region today while the next frontal system begins driving southward into the northern Plains. In between the surface pressure gradient will tighten up as will the height field, resulting in rather strong winds through the lower trop. The combination of this along with mixing will produce strong and gusty southwest winds. Both MOS values and wind gusts from the HRRR and RAP suggest winds will meet advisory criteria across central and northeast Missouri into west central Illinois with wind gusts of 40 kts possible. This regime is also favorable for a good warm-up even with the very cold start, and have highs above the MOS guidance. Glass .LONG TERM: (Tonight through Thursday) Issued at 330 AM CST Fri Jan 24 2014 A nw flow shortwave and attendant ULJ will dig into the area tonight sending another cold front through the region. As has been the case recently, strong and gusty northwest winds will accompany the front. Large scale ascent associated with the shortwave appears sufficient to produce an area of light snow across northeast Missouri into western Illinois. Currently it looks like the St. Louis region will be on the western fringe of the snow field. I have bumped up pops in the high chance to likely category within the aforementioned zone, and anticipate amounts from a dusting to less than an inch. We remain in cyclonic flow and northwest winds on Saturday with temperatures expected to remain below average. The temperature see-saw then continues on Sunday as the weak high pressure ridge departs quickly on Saturday night and we are well into low-level warm advection just after midnight. Strong warm advection on Sunday and gusty southwest-west winds once again suggest a good warm-up with highs getting well above normal. Enjoy the "warmth" because it is all downhill after Sunday. The next formidable Arctic front/blast comes roaring into the region on Sunday night and the airmass with this front is the coldest since the early January Arctic outbreak. A large full latitude longwave trof will continue to dominate central and eastern NOAM through the middle of next week keeping very cold conditions locked in across the region. The models are finally showing signs this blocky cold pattern breaking down and by early February suggest a negative phase of the PNA pattern will become established. Glass && .AVIATION: (For the 12z TAFs through 12z Saturday Morning) Issued at 546 AM CST Fri Jan 24 2014 As surface ridge moves off the south today, next system to approach area from the north tightening the gradient. So will see winds pickup and veer to the southwest this morning with gusts near 35 kts at times, especially over central and northeast Missouri as well as west central Illinois. Mid and high clouds to be on the increase as system gets closer. Then winds to diminish just a bit this evening before veering to the west to northwest after 06z Saturday as frontal boundary moves through, but winds will continue to gust to near 25kts at times. Cigs to lower to low end vfr/high end mvfr as front moves through. Some light snow is possible with this front, mainly along and east of Mississippi River, so added mention to KUIN with flurries in metro area tafs. Specifics for KSTL: As surface ridge moves off the south today, next system to approach area from the north tightening the gradient. So will see winds pickup and veer to the southwest this morning with gusts near 30 kts at times. Mid and high clouds to be on the increase as system gets closer. Then winds to diminish just a bit by 03z Saturday before veering to the northwest by 09z Saturday as frontal boundary moves through, but winds will continue to gust to near 25kts at times. Cigs to lower to low end vfr as front moves through. Some light snow is possible with this front, mainly east of Mississippi River, so added mention of flurries in metro area tafs. Byrd && .FIRE WEATHER: Issued at 420 AM CST Fri Jan 24 2014 The previously coordinated and issued Red Flag Warning still looks on target with strong and gusty southwest winds, very low afternoon RH, and 10h fuel moisture below 9%. The only change was to add a few more counties to the northwest of the previous area due to warmer temps and lower RH, so now all of central, east central, and southeast Missouri is under a Red Flag Warning. Glass && .LSX WATCHES/WARNINGS/ADVISORIES: MO...RED FLAG WARNING from 10 AM this morning to 7 PM CST this evening FOR Audrain MO-Boone MO-Callaway MO-Cole MO- Crawford MO-Dent MO-Franklin MO-Gasconade MO-Iron MO- Jefferson MO-Lincoln MO-Madison MO-Moniteau MO-Monroe MO- Montgomery MO-Osage MO-Reynolds MO-St. Charles MO-St. Francois MO-St. Louis City MO-St. Louis MO-Ste. Genevieve MO-Warren MO-Washington MO. WIND ADVISORY from 10 AM this morning to 6 PM CST this evening FOR Audrain MO-Boone MO-Callaway MO-Cole MO-Knox MO-Lewis MO-Marion MO-Moniteau MO-Monroe MO-Montgomery MO-Osage MO- Pike MO-Ralls MO-Shelby MO. IL...WIND ADVISORY from 10 AM this morning to 6 PM CST this evening FOR Adams IL-Brown IL-Pike IL. && $$ WFO LSX
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
537 AM CST FRI JAN 24 2014 .DISCUSSION... Issued at 358 AM CST FRI JAN 24 2014 Today: Primary focus will be on strong wind potential and critical fire danger (see FIRE WEATHER section below). For the umpteenth time this month, yet another strong mid level gyre will drop south from central Canada, replacing the arctic air with increasingly mild conditions. Surface pressures which started out at around 1044mb at 00Z, will crash to near 1014mb by 00Z this evening. Aches and pains alert! Incredible 30mb/24-hour pressure falls, coupled with 50-60 knot 925mb flow, will once again set the stage for very windy conditions across the region. As has been the case with the last several wind events, strong vertical mixing and downward momentum transfer will contribute to very strong gusts that will be well above what is "typically" expected for forecast sustained winds of 15 to 25 mph. Other than scattered mid cloud, ample sunshine should help realize nearly maximum gust potential, with the RAP and HRRR both suggesting widespread gusts exceeding 40 knots from late morning through mid afternoon, as the pressure wave pushes southeast. Have collaborated a wind advisory which will run from 10AM through 2PM across far NW MO/NE KS, and through 6PM across most of west central/central/northeast MO into far eastern Kansas. Despite the southwest winds, warm advection will lag quite a bit, with most of the diurnal temperature boost coming in the 11AM-3PM time frame. As a result, another very cold start expected this morning with wind chills in the -5 to -10F range as the kids head to the bus stop. Tonight-Saturday: Deep mixing will keep temperatures relatively mild tonight with lows running some 20 degrees warmer than this morning. A few flurries to a light dusting of snow could glance the far NE counties, but the bulk of any very minor accumulations should once again fall well east of the region as the strongest mid level ascent shifts into the Great Lakes and Ohio Valley. Weak cyclonic flow and cloud cover beneath and intense upper jet will lend to a challenging temperature forecast Saturday. High temperatures will range some 15-20 degrees from the upper 20s near Kirksville to the mid 40s across west central MO, and the gradient magnitude varies considerably among the 00Z models. Sunday-Sunday Night: Low level temps will steadily warm Saturday night and early Sunday ahead of the next arctic blast. 925mb temps could reach +10C, suggesting that temperatures will likely reach the low-mid 50s across all but far nrn MO before frontal passage late in the afternoon. Definitely the mildest day in the coming week. In a reversal of fortune so to speak, surface pressures will increase 30mb from 12Z Sunday to 12Z Monday, coincident with a strong arctic blast trailing yet another Canadian Clipper. Temperatures will plummet some 45 to 50 degrees from Sunday afternoon to Monday morning, and I would not be surprised to see wind gusts again in the 30-40 mph range Sunday evening. (Need to do some research as I cannot ever recall this magnitude of wind in January across Missouri). Monday-Thursday: See no change in the overall upper flow pattern to round out the end of the month. Above average confidence in little to no measurable precipitation, and above average confidence in much below normal temperatures Monday/Tuesday, then trending back toward normal Wednesday/Thursday ahead of the next closed low in the sequence dropping south through the Canadian Prairies. && .FIRE WEATHER... Issued at 358 AM CST FRI JAN 24 2014 Dangerous fire weather conditions are expected along and south of a St. Joseph to Carrollton to Moberly line from late morning through mid afternoon. Early morning observations show a very dry boundary layer in place with dewpoints in the single digits below zero. Very little moderate of this airmass is expected as temperatures steadily warm into the upper 30s to mid 40s this afternoon, yielding relative humidity values between 18 and 25%. The very dry airmass and 10-hour fuel stick moistures of 7-8% will contribute to a very volatile setup as southwest winds increase to 20 to 25 mph with gusts up to 45 mph. Given the potential for rapid grassland fire spread, a red flag warning remains in effect from 10AM thru 8PM for the aforementioned areas. && .AVIATION...(For the 12Z TAFS through 12Z Saturday Morning) Issued at 535 AM CST FRI JAN 24 2014 Low level wind shear will continue for the next couple of hours (SE 50 knots at 2Kft AGL), until stronger winds begin to mix down to the surface by mid morning. Already seeing the beginning of that with 20-25 knot gusts across NW MO. Conservatively could see winds gust 30 to 35 knots during the late morning and most of the afternoon, and would not be surprised to see a few gusts in the 40 to 45 knot range, especially where favored at MCI. Otherwise, VFR conditions expected through the period with patches of mid-high cloud today. && .EAX WATCHES/WARNINGS/ADVISORIES... KS...RED FLAG WARNING from 10 AM this morning to 8 PM CST this evening FOR KSZ025-057-060-102>105. WIND ADVISORY from 10 AM this morning to 6 PM CST this evening FOR KSZ057-060-103>105. WIND ADVISORY from 10 AM this morning to 2 PM CST this afternoon FOR KSZ025-102. MO...RED FLAG WARNING from 10 AM this morning to 8 PM CST this evening FOR MOZ020>022-028>033-037>040-043>046-053-054. WIND ADVISORY from 10 AM this morning to 6 PM CST this evening FOR MOZ008-017-021>025-028>033-037>040-043>046-053-054. WIND ADVISORY from 10 AM this morning to 2 PM CST this afternoon FOR MOZ001>007-011>016-020. && $$ DISCUSSION...Bookbinder AVIATION...Bookbinder FIRE WEATHER...Bookbinder
AREA FORECAST DISCUSSION...UPDATED
NWS ST LOUIS MO
425 AM CST Fri Jan 24 2014 .SHORT TERM: (Through Late This Afternoon) Issued at 330 AM CST Fri Jan 24 2014 The large Arctic high will continue to sink southward away from the region today while the next frontal system begins driving southward into the northern Plains. In between the surface pressure gradient will tighten up as will the height field, resulting in rather strong winds through the lower trop. The combination of this along with mixing will produce strong and gusty southwest winds. Both MOS values and wind gusts from the HRRR and RAP suggest winds will meet advisory criteria across central and northeast Missouri into west central Illinois with wind gusts of 40 kts possible. This regime is also favorable for a good warm-up even with the very cold start, and have highs above the MOS guidance. Glass .LONG TERM: (Tonight through Thursday) Issued at 330 AM CST Fri Jan 24 2014 A nw flow shortwave and attendant ULJ will dig into the area tonight sending another cold front through the region. As has been the case recently, strong and gusty northwest winds will accompany the front. Large scale ascent associated with the shortwave appears sufficient to produce an area of light snow across northeast Missouri into western Illinois. Currently it looks like the St. Louis region will be on the western fringe of the snow field. I have bumped up pops in the high chance to likely category within the aforementioned zone, and anticipate amounts from a dusting to less than an inch. We remain in cyclonic flow and northwest winds on Saturday with temperatures expected to remain below average. The temperature see-saw then continues on Sunday as the weak high pressure ridge departs quickly on Saturday night and we are well into low-level warm advection just after midnight. Strong warm advection on Sunday and gusty southwest-west winds once again suggest a good warm-up with highs getting well above normal. Enjoy the "warmth" because it is all downhill after Sunday. The next formidable Arctic front/blast comes roaring into the region on Sunday night and the airmass with this front is the coldest since the early January Arctic outbreak. A large full latitude longwave trof will continue to dominate central and eastern NOAM through the middle of next week keeping very cold conditions locked in across the region. The models are finally showing signs this blocky cold pattern breaking down and by early February suggest a negative phase of the PNA pattern will become established. Glass && .AVIATION: (For the 06z TAFs through 06z Friday Night) Issued at 1155 PM CST Thu Jan 23 2014 VFR fcst with sfc ridge settling south into TX tonight. Main story will be the gusty SSW winds on Friday. Winds are in the process of going sthrly tonight. All model guidance indicates 40 to 60 kts of wind just a couple thousand feet off the ground. Some of this is fcst to mix to the sfc. The pressure gradient also increases significantly tomorrow. This means sustained wind near 20 kts with gusts 30 to 35kts. This could lead to crosswind concerns on certain runway configurations. Removed the mention of LLWS except at KCPS and KSUS. Think that the threat remains marginal as the winds aloft arrive just before mixing begins. I think there may still be a brief window of a couple hrs as mixing is delayed due to the location of the arpts in river valleys. Otherwise...expect an increase in mid/high level cloudiness and continued gusty winds. Specifics for KSTL: VFR fcst with the main concern gusty SSW winds. This will likley become a crosswind concern later Friday morning and continuing thru the rest of the day. Winds eventually will become NW by Saturday morning. I removed the mention of LLWS as the window of opportunity looks too narrow on the order of a couple hrs. The stronger winds aloft arrive just before mixing begins. 2% && .FIRE WEATHER: Issued at 420 AM CST Fri Jan 24 2014 The previously coordinated and issued Red Flag Warning still looks on target with strong and gusty southwest winds, very low afternoon RH, and 10h fuel moisture below 9%. The only change was to add a few more counties to the northwest of the previous area due to warmer temps and lower RH, so now all of central, east central, and southeast Missouri is under a Red Flag Warning. Glass && .LSX WATCHES/WARNINGS/ADVISORIES: MO...RED FLAG WARNING from 10 AM this morning to 7 PM CST this evening FOR Audrain MO-Boone MO-Callaway MO-Cole MO- Crawford MO-Dent MO-Franklin MO-Gasconade MO-Iron MO- Jefferson MO-Lincoln MO-Madison MO-Moniteau MO-Monroe MO- Montgomery MO-Osage MO-Reynolds MO-St. Charles MO-St. Francois MO-St. Louis City MO-St. Louis MO-Ste. Genevieve MO-Warren MO-Washington MO. WIND ADVISORY from 10 AM this morning to 6 PM CST this evening FOR Audrain MO-Boone MO-Callaway MO-Cole MO-Knox MO-Lewis MO-Marion MO-Moniteau MO-Monroe MO-Montgomery MO-Osage MO- Pike MO-Ralls MO-Shelby MO. IL...WIND ADVISORY from 10 AM this morning to 6 PM CST this evening FOR Adams IL-Brown IL-Pike IL. && $$ WFO LSX
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
358 AM CST Fri Jan 24 2014 .DISCUSSION... Issued at 358 AM CST FRI JAN 24 2014 Today: Primary focus will be on strong wind potential and critical fire danger (see FIRE WEATHER section below). For the umpteenth time this month, yet another strong mid level gyre will drop south from central Canada, replacing the arctic air with increasingly mild conditions. Surface pressures which started out at around 1044mb at 00Z, will crash to near 1014mb by 00Z this evening. Aches and pains alert! Incredible 30mb/24-hour pressure falls, coupled with 50-60 knot 925mb flow, will once again set the stage for very windy conditions across the region. As has been the case with the last several wind events, strong vertical mixing and downward momentum transfer will contribute to very strong gusts that will be well above what is "typically" expected for forecast sustained winds of 15 to 25 mph. Other than scattered mid cloud, ample sunshine should help realize nearly maximum gust potential, with the RAP and HRRR both suggesting widespread gusts exceeding 40 knots from late morning through mid afternoon, as the pressure wave pushes southeast. Have collaborated a wind advisory which will run from 10AM through 2PM across far NW MO/NE KS, and through 6PM across most of west central/central/northeast MO into far eastern Kansas. Despite the southwest winds, warm advection will lag quite a bit, with most of the diurnal temperature boost coming in the 11AM-3PM time frame. As a result, another very cold start expected this morning with wind chills in the -5 to -10F range as the kids head to the bus stop. Tonight-Saturday: Deep mixing will keep temperatures relatively mild tonight with lows running some 20 degrees warmer than this morning. A few flurries to a light dusting of snow could glance the far NE counties, but the bulk of any very minor accumulations should once again fall well east of the region as the strongest mid level ascent shifts into the Great Lakes and Ohio Valley. Weak cyclonic flow and cloud cover beneath and intense upper jet will lend to a challenging temperature forecast Saturday. High temperatures will range some 15-20 degrees from the upper 20s near Kirksville to the mid 40s across west central MO, and the gradient magnitude varies considerably among the 00Z models. Sunday-Sunday Night: Low level temps will steadily warm Saturday night and early Sunday ahead of the next arctic blast. 925mb temps could reach +10C, suggesting that temperatures will likely reach the low-mid 50s across all but far nrn MO before frontal passage late in the afternoon. Definitely the mildest day in the coming week. In a reversal of fortune so to speak, surface pressures will increase 30mb from 12Z Sunday to 12Z Monday, coincident with a strong arctic blast trailing yet another Canadian Clipper. Temperatures will plummet some 45 to 50 degrees from Sunday afternoon to Monday morning, and I would not be surprised to see wind gusts again in the 30-40 mph range Sunday evening. (Need to do some research as I cannot ever recall this magnitude of wind in January across Missouri). Monday-Thursday: See no change in the overall upper flow pattern to round out the end of the month. Above average confidence in little to no measurable precipitation, and above average confidence in much below normal temperatures Monday/Tuesday, then trending back toward normal Wednesday/Thursday ahead of the next closed low in the sequence dropping south through the Canadian Prairies. && .FIRE WEATHER... Issued at 358 AM CST FRI JAN 24 2014 Dangerous fire weather conditions are expected along and south of a St. Joseph to Carrollton to Moberly line from late morning through mid afternoon. Early morning observations show a very dry boundary layer in place with dewpoints in the single digits below zero. Very little moderate of this airmass is expected as temperatures steadily warm into the upper 30s to mid 40s this afternoon, yielding relative humidity values between 18 and 25%. The very dry airmass and 10-hour fuel stick moistures of 7-8% will contribute to a very volatile setup as southwest winds increase to 20 to 25 mph with gusts up to 45 mph. Given the potential for rapid grassland fire spread, a red flag warning remains in effect from 10AM thru 8PM for the aforementioned areas. && .AVIATION...(For the 06Z TAFS through 06Z Friday Night) Issued at 1111 PM CST THU JAN 23 2014 VFR conditions are expected through the entire forecast. The biggest concern will be from very strong and gusty south/southwesterly winds. Winds will increase around sunrise as the surface high pressure slides to the south and east and the pressure gradient really strengthens across the area. As deeper mixing develops later in the morning and this afternoon winds will become quite strong and gusty. Have increased winds into the 25kt sustained 35kt gust range. Winds potentially could be stronger if the pressure gradient and deepest mixing occur together. But for now this looks to occur south and east of the terminals. A secondary concern is for LLWS late tonight through a few hours after sunrise, before deeper mixing develops. Winds aloft will be very strong, possibly around 50 kts. This will occur prior to the surface pressure gradient strengthening. As a result have added LLWS to the forecast. && .EAX WATCHES/WARNINGS/ADVISORIES... KS...RED FLAG WARNING from 10 AM this morning to 8 PM CST this evening FOR KSZ025-057-060-102>105. WIND ADVISORY from 10 AM this morning to 6 PM CST this evening FOR KSZ057-060-103>105. WIND ADVISORY from 10 AM this morning to 2 PM CST this afternoon FOR KSZ025-102. MO...RED FLAG WARNING from 10 AM this morning to 8 PM CST this evening FOR MOZ020>022-028>033-037>040-043>046-053-054. WIND ADVISORY from 10 AM this morning to 6 PM CST this evening FOR MOZ008-017-021>025-028>033-037>040-043>046-053-054. WIND ADVISORY from 10 AM this morning to 2 PM CST this afternoon FOR MOZ001>007-011>016-020. && $$ DISCUSSION...Bookbinder AVIATION...CDB FIRE WEATHER...Bookbinder
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
339 AM CST Fri Jan 24 2014 .SHORT TERM: (Through Late This Afternoon) Issued at 330 AM CST Fri Jan 24 2014 The large Arctic high will continue to sink southward away from the region today while the next frontal system begins driving southward into the northern Plains. In between the surface pressure gradient will tighten up as will the height field, resulting in rather strong winds through the lower trop. The combination of this along with mixing will produce strong and gusty southwest winds. Both MOS values and wind gusts from the HRRR and RAP suggest winds will meet advisory criteria across central and northeast Missouri into west central Illinois with wind gusts of 40 kts possible. This regime is also favorable for a good warm-up even with the very cold start, and have highs above the MOS guidance. Glass .LONG TERM: (Tonight through Thursday) Issued at 330 AM CST Fri Jan 24 2014 A nw flow shortwave and attendant ULJ will dig into the area tonight sending another cold front through the region. As has been the case recently, strong and gusty northwest winds will accompany the front. Large scale ascent associated with the shortwave appears sufficient to produce an area of light snow across northeast Missouri into western Illinois. Currently it looks like the St. Louis region will be on the western fringe of the snow field. I have bumped up pops in the high chance to likely category within the aforementioned zone, and anticipate amounts from a dusting to less than an inch. We remain in cyclonic flow and northwest winds on Saturday with temperatures expected to remain below average. The temperature see-saw then continues on Sunday as the weak high pressure ridge departs quickly on Saturday night and we are well into low-level warm advection just after midnight. Strong warm advection on Sunday and gusty southwest-west winds once again suggest a good warm-up with highs getting well above normal. Enjoy the "warmth" because it is all downhill after Sunday. The next formidable Arctic front/blast comes roaring into the region on Sunday night and the airmass with this front is the coldest since the early January Arctic outbreak. A large full latitude longwave trof will continue to dominate central and eastern NOAM through the middle of next week keeping very cold conditions locked in across the region. The models are finally showing signs this blocky cold pattern breaking down and by early February suggest a negative phase of the PNA pattern will become established. Glass && .AVIATION: (For the 06z TAFs through 06z Friday Night) Issued at 1155 PM CST Thu Jan 23 2014 VFR fcst with sfc ridge settling south into TX tonight. Main story will be the gusty SSW winds on Friday. Winds are in the process of going sthrly tonight. All model guidance indicates 40 to 60 kts of wind just a couple thousand feet off the ground. Some of this is fcst to mix to the sfc. The pressure gradient also increases significantly tomorrow. This means sustained wind near 20 kts with gusts 30 to 35kts. This could lead to crosswind concerns on certain runway configurations. Removed the mention of LLWS except at KCPS and KSUS. Think that the threat remains marginal as the winds aloft arrive just before mixing begins. I think there may still be a brief window of a couple hrs as mixing is delayed due to the location of the arpts in river valleys. Otherwise...expect an increase in mid/high level cloudiness and continued gusty winds. Specifics for KSTL: VFR fcst with the main concern gusty SSW winds. This will likley become a crosswind concern later Friday morning and continuing thru the rest of the day. Winds eventually will become NW by Saturday morning. I removed the mention of LLWS as the window of opportunity looks too narrow on the order of a couple hrs. The stronger winds aloft arrive just before mixing begins. 2% && .FIRE WEATHER: Issued at 215 AM CST Thu Jan 23 2014 After coordinating with surrounding offices, as well as USFS and MO Dept of Conservation, will be issuing a Red Flag Warning for parts of central and east central Missouri, as well as much of southeast Missouri, for late Friday morning into Friday evening. Setup looks favorable for a strong warmup while surface ridge to our south blocks any significant moisture return. Red Flag criteria should easily be met...10hr fuel moisture values below 8% (criteria less than 9%), sustained SW winds at least 20 mph (criteria greater than 15 mph) with higher gusts, and latest temp/dewpoint forecasts suggests afternoon RH values below 20% roughly along and south of a COU- Ste. Genevieve line (criteria less than 25%). Truett && .LSX WATCHES/WARNINGS/ADVISORIES: MO...RED FLAG WARNING from 10 AM this morning to 7 PM CST this evening FOR Audrain MO-Boone MO-Callaway MO-Cole MO- Crawford MO-Dent MO-Franklin MO-Gasconade MO-Iron MO- Jefferson MO-Lincoln MO-Madison MO-Moniteau MO-Monroe MO- Montgomery MO-Osage MO-Reynolds MO-St. Charles MO-St. Francois MO-St. Louis City MO-St. Louis MO-Ste. Genevieve MO-Warren MO-Washington MO. WIND ADVISORY from 10 AM this morning to 5 PM CST this afternoon FOR Audrain MO-Boone MO-Callaway MO-Cole MO-Knox MO-Lewis MO-Marion MO-Moniteau MO-Monroe MO-Montgomery MO-Osage MO- Pike MO-Ralls MO-Shelby MO. IL...WIND ADVISORY from 10 AM this morning to 5 PM CST this afternoon FOR Adams IL-Brown IL-Pike IL. && $$ WFO LSX
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
344 AM CST SAT JAN 25 2014 .SYNOPSIS... ISSUED AT 343 AM CST SAT JAN 25 2014 AN ARCTIC FRONT IS CURRENTLY SITUATED NEAR MOBRIDGE THROUGH HURON SOUTH DAKOTA. MEANWHILE...A WEAK DISTURBANCE CONTINUES TO BRING LIGHT RAIN SHOWERS OR SPRINKLES TO WESTERN SOUTH DAKOTA INTO NORTH CENTRAL NEBRASKA. A MIXED ATMOSPHERE ALSO KEEPING EARLY MORNING TEMPERATURES UP INTO THE LOWER 40S ACROSS MOST OF WESTERN NEBRASKA. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 343 AM CST SAT JAN 25 2014 THE ARCTIC FRONT WILL BACK SOUTHWESTWARD TO NEAR A PIERRE THROUGH ONEILL LINE BY 18Z TODAY. THE FRONT WILL THEN RETREAT QUICKLY EASTWARD AS A WARM FRONT THIS AFTERNOON. CLOUDS WILL ALSO THIN OUT FROM WEST TO EAST TODAY. WENT NEAR PREVIOUS HIGHS IN THE WEST AND SOUTHWEST IN THE 50S...AND SLIGHTLY WARMER IN THE CENTRAL AND EAST TO THE MID AND UPPER 40S. THE EXCEPT IN THE FAR NORTHEAST INCLUDING ONEILL WHERE HIGHS ONLY WARMING TO THE UPPER 30S. THE WEAK DISTURBANCE COLOCATED IN THE RIGHT ENTRANCE REGION OF A 140 KNOT JET MAX WILL CONTINUE TO BRING EITHER SPRINKLES OR SLIGHT CHC OF -RW TO THE NORTHEASTERN HALF OF THE FA THIS MORNING. ANY OF THIS ACTIVITY SHOULD END BY 18Z. FIRE WEATHER CONCERNS ARE MINIMIZED SOMEWHAT THIS AFTERNOON WITH MINIMUM RELATIVE HUMIDITY NEAR 30 PERCENT FOR AREAS SOUTHWEST OF HYANNIS THROUGH NORTH PLATTE. FORECAST TEMPERATURE DEWPOINT SPREAD INCREASES TO ABOUT 30 DEGREES WHICH IS NOT NEARLY AS EXCESSIVE AS LAST TUESDAY WHEN THE SPREAD WAS ABOUT 50 DEGREES. TONIGHT...MOST AREAS TO REMAIN MIXED WITH MILD H85 TEMPS NEAR 10C IN SRN NEBR AT 06Z. MOST AREAS TO REMAIN WELL INTO THE 40S THROUGH THE EVENING. DO EXPECT SOME DECOUPLING OVERNIGHT WITH LOWS TO DIP INTO THE LOWER 30S. MEANWHILE...THE ARCTIC FRONT WILL DROP INTO CENTRAL NORTH DAKOTA BY 12Z SUNDAY. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 343 AM CST SAT JAN 25 2014 COLD FRONT ARRIVES SUNDAY WITH SEVERAL CONCERNS FOR THE DAY. SOUNDING LIKE A BROKEN RECORD WITH VERY STRONG WINDS DEVELOPING BEHIND THE FRONT...ESPECIALLY ACROSS N CENTRAL. 850 MB WINDS AROUND 50 KTS FOR THE AFTERNOON WITH STRONG COLD AIR ADVECTION TO HELP MIX THE STRONGER WINDS TO THE SFC. GUIDANCE GENERALLY CLOSE TO OR ABOVE HIGH WIND WARNING FOR AREAS ALONG EAST OF A KVTN TO KBBW LINE...THUS WILL ISSUE A WATCH. REST OF THE CWA WILL CONTINUE TO BE MONITORED...HOWEVER EXPECT AT LEAST AN ADVISORY. ALSO EXPECTING AT LEAST SOME SCT SNOW SHOWERS WITH THE STEEP LAPSE RATES. INITIALLY COULD SEE A MIX RAIN AND SNOW AS TEMPS COULD STILL BE IN THE 30S AS PRECIP STARTS...HOWEVER THE MIX WILL BE SHORT LIVED. TEMPS TRICKY AS TIMING OF THE FRONT CRITICAL TO HIGHS. EXPECT MORNING HIGHS ACROSS THE NORTH...THEN FALLING MORE LIKE CRASHING TEMPS. EARLY HIGHS ACROSS THE NORTH LIKELY WELL INTO THE 30S AND LOCALLY COULD TOP 40...HOWEVER BY LATE AFTERNOON TEMPS WILL BE WELL INTO THE 20S...IF NOT INTO THE TEENS. SUNDAY NIGHT AS TEMPS CONTINUE TO FALL INTO TO AROUND ZERO AND WINDS ARE SLOW TO DIMINISH...ANOTHER HEADLINE IS POSSIBLE. THIS TIME FOR WIND CHILLS...AT LEAST TO 20 BELOW ZERO IS POSSIBLE...OR ADVISORY CRITERIA...MAINLY ACROSS THE NE PART OF THE CWA. TO EARLY TO ISSUE THIS YET...BUT IT WILL BE MENTIONED IN THE HWO. SNOW CHANCES OVERNIGHT SHOULD BE CONFINED TO UPSLOPE FLOW CLOSER TO THE FRONT RANGE. CONTINUED FLURRIES IN FAR SW ZONES...HOWEVER WOULD NOT BE SURPRISED IF ACTIVITY REMAINS TO THE WEST OF THE CWA. WORK WEEK STARTS OUT COLD WITH ARCTIC HIGH PRESSURE BUILDING SOUTH ACROSS THE NORTHERN PLAINS. HIGHS STRUGGLE FOR MOST AREAS TO ONLY REACH THE TEENS...WITH 20S ACROSS THE SW. MODELS FAVOR UPSLOPE LIGHT PRECIP TO THE WEST OF THE CWA. PRESSURE GRADIENT SLACKENS WITH WINDS STILL ON THE BREEZY SIDE WITH 15 TO 20 MPH AS CENTER OF THE HIGH REMAINS ACROSS THE DAKOTAS. MONDAY NIGHT INTO WEDNESDAY THE HIGH SLOWLY SHIFTS TOWARDS THE MID MISS RVR VALLEY...WHICH HAS BEEN THE FAVORED SFC HIGH PRESSURE TRACK LATELY...WHICH WILL ALLOW FOR WARMER AIR TO EVENTUALLY FILL IN FROM THE WEST. COLD AIR STILL ACROSS THE AREA FOR TUESDAY WITH HIGHS STRUGGLING AGAIN INTO THE TEENS AND 20S...THEN AS WARM AIR ADVECTION KICKS IN FOR WEDNESDAY...HIGHS REBOUND INTO THE MID 30S TO MID 40S. THE END OF NEXT WEEK BECOMES MORE UNUSUALLY FOR THIS WINTER AS A TROUGH DIGS INTO THE PAC NW...BREAKING THE WESTERN RIDGE DOWN A LITTLE. WITH QUASI ZONAL FLOW DEVELOPING LATE IN THE WEEK MODELS BRING A COUPLE OF DISTURBANCES ACROSS THE PLAINS. THEN AS THE TROUGH ROTATES THROUGH THE SW A BRIEF PERIOD BY NEXT WEEKEND LOOKS TO BE SW FLOW. STILL ISSUES WITH TIMING AND EXACT TRACK...HOWEVER THIS APPEARS TO BE OUR BEST SHOT AS MEASURABLE PRECIP IN A WHILE. INITIALLY WAVES WILL HAVE LITTLE MOISTURE TO WORK WITH SO EXPECT THE END OF THE WORK WEEK TO BE GENERALLY DRY...ALTHOUGH AN INCREASE IS CLOUD COVER IS EXPECTED. TEMPS WILL ALSO BE CLOSER TO SEASONAL...ALTHOUGH WITH THE ADDED CLOUD COVER...LOWS MAY BE ON THE MILD SIDE. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 1107 PM CST FRI JAN 24 2014 THE NAM...RAP...SREF AND RAP ARE SHOWING MVFR CIGS MOVING INTO NCNTL NEB TONIGHT AND LIFTING SLOWLY NORTHEAST DURING THE DAY SATURDAY. THE SREF SHOWS A HIGH PROBABILITY OF A SMALL AREA OF IFR CIGS NEAR KVTN-KANW FOR A FEW HOURS AROUND SUNRISE. NONE OF THESE CIGS WILL AFFECT KLBF. A FEW GUSTS TO 40KT CONTINUE TONIGHT NEAR FROM KVTN- KBBW. SO...WEST OF A LINE FROM KVTN-KBBW...VFR IS EXPECTED OVERNIGHT THROUGH SATURDAY EVENING AND VFR IS EXPECTED EAST OF THIS LINE AFTER ABOUT 21Z-00Z SATURDAY. && .LBF WATCHES/WARNINGS/ADVISORIES... HIGH WIND WATCH FROM SUNDAY AFTERNOON THROUGH SUNDAY EVENING FOR NEZ005>010-026>029-038. && $$ SYNOPSIS...ROBERG SHORT TERM...ROBERG LONG TERM...MASEK AVIATION...CDC
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
1114 PM CST FRI JAN 24 2014 .SYNOPSIS... ISSUED AT 311 PM CST FRI JAN 24 2014 A HIGHLY AMPLIFIED PATTERN CONTINUES ACROSS THE CONUS TDY. CLOSED LOW PRESSURE WAS NOTED OVER NORTHERN HUDSON BAY WITH A TROUGH EXTENDING SWD INTO THE CAROLINAS AND FLORIDA. FURTHER WEST...A RIDGE EXTENDED FROM OREGON NWD INTO THE YUKON AND EASTERN ALASKA. UNDERNEATH THE RIDGE...A LOW WAS LOCATED OFF THE COAST OF NRN CALIFORNIA. ACROSS THE CENTRAL CONUS...NNWRLY FLOW CONTINUED WITH 50 TO 100 METER HT FALLS NOTED OVER NRN MN...SRN MANITOBA AND WESTERN ONTARIO. AT THE SURFACE...A DECENT PRESSURE GRADIENT EXISTED ACROSS THE CENTRAL AND NORTHERN PLAINS BETWEEN HIGH PRESSURE OVER THE WESTERN SLOPE OF THE ROCKIES AND LOW PRESSURE OVER ONTARIO. AS A RESULT OF THE TIGHT PRESSURE GRADIENT...WINDY CONDITIONS WERE PRESENT ACROSS THE REGION THIS AFTERNOON. SUSTAINED WINDS OF 20 TO 35 MPH WERE COMMON WITH SOME INFREQUENT GUSTS AROUND 40 MPH. SKIES WERE MOSTLY CLOUDY IN CENTRAL AND EASTERN AREAS AND PARTLY CLOUDY IN THE WEST WITH SOME PATCHY BLOWING DUST ACROSS THE SOUTHEASTERN NEBRASKA PANHANDLE AND FAR SOUTHWESTERN NEBRASKA. TEMPERATURES AS OF 2 PM CST RANGED FROM 49 AT ONEILL...TO 57 AT IMPERIAL. && .SHORT TERM...(THIS EVENING THROUGH SATURDAY) ISSUED AT 311 PM CST FRI JAN 24 2014 A MILD NIGHT IS IN STORE FOR WESTERN AND NORTH CENTRAL NEBRASKA...AS WARMER AIR ALOFT WILL CONTINUE TO MIX TO THE SURFACE THROUGH THE NIGHT. MID AND HIGH LEVEL CLOUDS WILL CONTINUE TO STREAM SOUTHEAST ACROSS THE AREA...AND A FEW RAIN OR SNOW SHOWERS CONTINUE TO LOOK POSSIBLE ACROSS NORTH CENTRAL NEBRASKA AS A WEAK UPPER LEVEL IMPULSE MOVES THROUGH IN NORTHWEST FLOW ALOFT. ANOTHER MILD DAY EXPECTED SATURDAY...AS WESTERLY DOWNSLOPE WINDS CONTINUE. HIGHS BACK INTO THE 50S FOR MOST...WITH 40S ACROSS CENTRAL NEBRASKA. WINDS WILL NOT BE AS STRONG...WITH A GENERAL 10 TO 20 MPH RANGE EXPECTED. .LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY) ISSUED AT 311 PM CST FRI JAN 24 2014 GUIDANCE HAS WIND RELATIVELY STRONG /AOA 15 KTS AT THE SFC/ WHICH WILL HELP KEEP TEMPERATURES FAIRLY MILD SATURDAY NIGHT ACROSS THE CWA. MOST AREAS WILL STAY AROUND FREEZING WITH TEMPS A LITTLE LOWER IN THE PLATTE RIVER VALLEY. THE MAIN CONCERN COMES SUNDAY WITH THE ARRIVAL OF ANOTHER ARCTIC FRONT. NAM...GFS...AND EURO ALL SHOW SIMILAR TIMING OF THE FRONTAL PASSAGE SUNDAY AFTERNOON OR EVENING. WENT WITH GENERAL BLEND OF NAM AND GFS FOR TEMPERATURES SUNDAY. TEMPS CRASH BEHIND THE FRONT /AFTER 18Z/ SO NON-DIURNAL TREND USED FOR NORTHERN HALF OF CWA. CROSS SECTIONS AND SIMULATED SOUNDINGS SHOW A MODEST AMOUNT OF INSTABILITY AND QUASI ADIABATIC LAPSE RATES ALONG THE FRONT. TEMPS WILL BE ABLE TO WARM INTO THE 40S FOR PORTIONS OF SOUTHERN HALF OF CWA...WHERE RAIN/SNOW MIX WAS INTRODUCED. ALL SNOW WAS KEPT NORTH...WHERE DROPPING TEMPS ARRIVE EARLIER IN THE DAY. CROPPED PRECIP CHANCES TO THE FAR SOUTHWEST CWA SUNDAY NIGHT INTO MONDAY FOR UPSLOPE NORTHEASTERLY FLOW. CONFIDENCE IN PRECIP MAKING IT THIS FAR EAST FROM THE ROCKIES IS SOMEWHAT LOW...SO KEPT PRECIP MENTION AS FLURRIES. HIGH WINDS ARE ALSO A CONCERN AS GUIDANCE PUSHES WINDS TO ADVISORY AND EVEN NEAR WARNING CRITERIA...ESPECIALLY EASTERN HALF OF CWA SUNDAY AFTERNOON. WILL HAVE TO WATCH FOR WIND CHILL HEADLINES MONDAY MORNING AS COLD AIR ADVECTION WILL ALLOW WINDS TO PERSIST INTO THE OVERNIGHT...BEFORE DIMINISHING NEAR SUNRISE MONDAY MORNING. TEMPS WILL CRASH OVERNIGHT WITH READINGS RANGING FROM AROUND 5 BELOW IN THE NORTHEAST TO NEAR 10 ABOVE IN THE FAR SOUTHWEST. FOR MONDAY...TEMPERATURES WILL STRUGGLE TO GET OUT OF THE TEENS ACROSS THE NORTH AND 20S FAR SOUTH. MONDAY NIGHT THROUGH FRIDAY... TEMPERATURES ARE THE BIGGEST CHALLENGE THROUGH THE EXTENDED PERIOD WITH THE FIRST COLD WAVE CONTINUING TO AFFECT THE AREA TUESDAY AND A SECOND WAVE ARRIVING LATE WEEK. MEX AND ECE ARE IN GENERAL AGREEMENT FOR DOWNWARD TRENDING TEMPS MONDAY NIGHT THROUGH TUESDAY NIGHT SO LOWERED PREVIOUS MIN TEMPS A COUPLE DEGREES. FOR WEDNESDAY...THE SPREAD WIDENS BETWEEN THE TWO MODELS. WENT WITH A COMPROMISE AS THE ECE ALLOWS WARMING ALONG THE HIGH PLAINS AND MEX EXTENDING THE COLD AIR FROM THE GREAT LAKES BACK THROUGH THE CENTRAL PLAINS. TEMPS MODERATE FOR THE REMAINDER OF THE PERIOD. MOISTURE IS VIRTUALLY NON-EXISTENT TUESDAY THROUGH FRIDAY FOR THE ENTIRE CWA. HOWEVER...THE GFS AND EURO ARE TRYING TO CHANGE THE PATTERN NEXT WEEKEND BY FLATTENING THE WESTERN U.S. RIDGE AND BRINGING WESTERLY TO SOUTHWESTERLY FLOW. WITH NO MOISTURE ARRIVING UNTIL AFTER THE FORECAST PERIOD AND THE GEM NHEM KEEPING A HIGHLY AMPLIFIED PATTERN...HELD OFF ON ANY MENTION OF PRECIP. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 1107 PM CST FRI JAN 24 2014 THE NAM...RAP...SREF AND RAP ARE SHOWING MVFR CIGS MOVING INTO NCNTL NEB TONIGHT AND LIFTING SLOWLY NORTHEAST DURING THE DAY SATURDAY. THE SREF SHOWS A HIGH PROBABILITY OF A SMALL AREA OF IFR CIGS NEAR KVTN-KANW FOR A FEW HOURS AROUND SUNRISE. NONE OF THESE CIGS WILL AFFECT KLBF. A FEW GUSTS TO 40KT CONTINUE TONIGHT NEAR FROM KVTN- KBBW. SO...WEST OF A LINE FROM KVTN-KBBW...VFR IS EXPECTED OVERNIGHT THROUGH SATURDAY EVENING AND VFR IS EXPECTED EAST OF THIS LINE AFTER ABOUT 21Z-00Z SATURDAY. && .LBF WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...CLB SHORT TERM...TAYLOR LONG TERM...DS AVIATION...CDC
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
657 PM EST SAT JAN 25 2014 .SYNOPSIS... A COLD FRONT WILL PUSH SOUTH OF THE AREA TONIGHT. HIGH PRESSURE WILL BUILD EAST ACROSS THE OHIO VALLEY LATE TONIGHT INTO EARLY SUNDAY. THE NEXT CLIPPER WILL SLIDE SOUTHEAST ACROSS THE GREAT LAKES ON SUNDAY. THE NEXT PUSH OF ARCTIC AIR WILL ARRIVE BEHIND THIS SYSTEM AS ARCTIC HIGH PRESSURE BUILDS TOWARDS THE OHIO VALLEY THROUGH MID-WEEK. && .NEAR TERM /UNTIL 6 AM SUNDAY MORNING/... UPDATED TO FRESHEN UP THE WORDING BUT DID CONTINUE THE ADVISORY. CONTINUED THE ADVISORY IN THE WEST BECAUSE OF SOME BLOWING AND DRIFTING AND CONTINUED IT IN THE EAST WITH LAKE EFFECT SNOW SHOWERS. PREVIOUS DISCUSSION... WINTER WEATHER ADVISORIES REMAIN IN EFFECT UNTIL 10 PM. SNOW SQUALLS HAVE INTENSIFIED ACROSS NORTHEAST OHIO SINCE 1 PM AS THE COLD FRONT MOVES SOUTHEAST ACROSS THE AREA AND THE UPPER LEVEL TROUGH BEARS DOWN UPON US. THERE IS A CONVECTIVE COMPONENT TO THE SNOW SQUALLS AS THE COLD POOL ALOFT ARRIVES. SNOW MAY BE HEAVY AT TIMES THROUGH 7 PM...BUT THE TREND WILL BE TO PUSH INLAND INTO THIS EVENING AND WEAKEN AS THE SURFACE TROUGH PUSHES SOUTH. 1000-850MB OMEGA HAS BEEN DOING A GOOD JOB HIGHLIGHTING THIS THREAT AND BOTH THE NAM12 AND RUC13 SHOWS THE PEAK HAS OCCURRED. CONSIDERED CANCELLING THE ADVISORY IN NW OHIO BUT THERE IS SOME CONCERN THAT THE LAKE ENHANCED SNOW BANDS OVER NRN INDIANA WILL SPREAD INTO NW OHIO AS THE RIDGE BUILDS TO OUR SOUTH. ACCUMULATIONS WILL BE MINOR...AN INCH OR LOCALLY UP TO 2...BUT MOST AREAS WILL BE BELOW AN INCH. WINDS REMAIN GUSTY ENOUGH HOWEVER THAT THOUGHT IT WAS WORTH CONTINUING FOR A FEW MORE HOURS. WINDS WILL SHIFT TO THE WEST AND DECREASE THROUGH THE NIGHT TO AROUND 8-12 MPH BY MORNING. A WIND CHILL ADVISORY HAS BEEN ISSUED FOR THE WHOLE AREA STARTING AFTER 10 PM AS THE NEXT PUSH OF REALLY COLD AIR ARRIVES. && .SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY NIGHT/... SOUTHWEST FLOW WILL BRING THE NEXT ROUND OF WARM ADVECTION SNOW AHEAD OF THE CLIPPER THAT WILL MOVE ACROSS THE CENTRAL GREAT LAKES ON SUNDAY. SNOWFALL MAY BE AS HIGH AS 2-3 INCHES IN OUR SOUTHWESTERN COUNTIES BUT WILL ONCE AGAIN COMBINE WITH BRISK WIND TO CREATE BLOWING SNOW CONCERNS...ESPECIALLY IN NW OHIO WHERE THE LANDSCAPE IS MORE OPEN. ELSEWHERE SNOW WILL BE LESS THAN 2 INCHES. A WINTER WEATHER ADVISORY MAY BE NEEDED FOR AREAS FROM TOLEDO TO MOUNT VERNON BUT WANTED TO KEEP IT SEPARATE FROM THE CURRENT HEADLINES AS THERE WILL BE A SIZEABLE BREAK IN THE SNOW. TEMPERATURES WILL WARM ON SUNDAY AS WE GET INTO THE WARM SECTOR WITH HIGHS RANGING FROM THE UPPER TEENS IN NW PA TO UPPER 2OS IN NORTH CENTRAL OHIO. THE ASSOCIATED ARCTIC COLD FRONT PUSHES BACK SOUTH LATE SUNDAY NIGHT AND TEMPERATURES WILL FALL THROUGH THE DAY ON MONDAY. BY MONDAY NIGHT LOWS WILL FALL TO AROUND -5 DEGREES NEAR LAKE ERIE AND -10 TO -15 DEGREES INLAND. THIS WILL RESULT IN DANGEROUSLY COLD WIND CHILL VALUES NEAR -25 AND WILL BE ON THE FRINGE OF NEEDING EITHER A WIND CHILL ADVISORY OR WARNING. && .LONG TERM /TUESDAY THROUGH SATURDAY/... THE UPPER LEVEL PATTERN WILL REMAIN PRETTY MUCH UNCHANGED THROUGHOUT THE EXTENDED FORECAST PERIOD...HOWEVER BY THE END OF THE EXTENDED PERIOD LATE FRIDAY INTO NEXT WEEKEND LOOK FOR A SOUTHERLY FLOW TO PUSH TEMPERATURES POSSIBLY INTO THE UPPER 20S AND 30S. STILL COLD AND RAW TUESDAY WITH DAYTIME TEMPERATURES STRUGGLING TO GET INTO THE DOUBLE DIGITS. SLIGHTLY WARMER THURSDAY WITH HIGHS IN THE TEENS TO AROUND 20 AND SLIGHT WARM-UP FRIDAY WITH HIGHS IN THE 20S. WITH TEMPERATURES IN THE 20S FRIDAY THIS IS STILL ALMOST TEN DEGREES BELOW NORMAL FOR THIS TIME OF YEAR. && .AVIATION /00Z SUNDAY THROUGH THURSDAY/... MULTI LAKE FETCH FROM LAKE MICHIGAN TO LAKE ERIE CAUSING SOME LAKE EFFECT SNOW CLUSTERS AND SQUALLS TO DEVELOP AND MOVE SOUTHEAST INTO THE CLEVELAND AREA. A FEW RENEGADE FLURRIES AND SNOW SHOWERS CONTINUE AT AKRON CANTON...YOUNGSTOWN AND ERIE. THIS ACTIVITY IS EXPECTED TO CONTINUE THROUGH 1 AM IN THE MORNING AND THEN BEGIN TO WANE BY 4 AM. FINDLAY AND MANSFIELD MAY SEE A FLURRY OR TWO BUT ALONG WITH TOLEDO...OVERALL TREND IS FOR CLEARING SKIES THROUGH THE REST OF THE NIGHT. NEXT STORM SYSTEM WILL MOVE QUICKLY EAST ACROSS THE AREA TOMORROW AND NEW ROUND OF SNOW WITH THIS SYSTEM WILL HIT US LIKE A WALL...MOVE THROUGH THE AREA AND THEN BE DONE UNTIL THE LAKE EFFECT KICKS IN. WE COULD SEE A MIXED BAG OF CEILINGS AND VISIBILITIES THROUGH THE NEXT 24 HOURS. WINDS SHOULD DIE DOWN TONIGHT AND SHIFT TO MORE SOUTHWESTERLY AND FORCE SNOW SHOWERS UP THE LAKE SHORE EARLY TOMORROW MORNING. OUTLOOK...NON VFR INTO MONDAY. NON VFR MAINLY IN THE SNOW BELT MONDAY NIGHT INTO TUESDAY. && .MARINE... WILL CONTINUE GALE WARNING TIL 10 AM THIS MORNING AFTER COORDINATING WITH WFO BUF. WINDS WILL REMAIN FAIRLY GUSTY THROUGH TODAY WITH SOUTHWEST WINDS TO 30 TO 35 KNOTS BECOMING WESTERLY. ANOTHER WEATHER DISTURBANCE WILL BRING A CHANCE OF ANOTHER GALE SUNDAY NIGHT BUT WILL HOLD THE LINE TO RIGHT BELOW GALE CRITERIA AT THIS TIME. BEHIND THIS WEATHER SYSTEM LOOK FOR WEST TO SOUTHWEST WIND FLOW MONDAY INTO TUESDAY. WAVES WILL BE OMITTED DUE TO THE LAKE BEING MOSTLY ICE COVERED. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...WINTER WEATHER ADVISORY UNTIL 10 PM EST THIS EVENING FOR OHZ003-006>014-017>023-027>033-036>038-047-089. WIND CHILL ADVISORY FROM 10 PM THIS EVENING TO 10 AM EST SUNDAY FOR OHZ009>014-019>023-029>033-038-089. WIND CHILL ADVISORY FROM 10 PM THIS EVENING TO 7 AM EST SUNDAY FOR OHZ003-006>008-017-018-027-028-036-037-047. PA...WINTER WEATHER ADVISORY UNTIL 10 PM EST THIS EVENING FOR PAZ001>003. WIND CHILL ADVISORY FROM 10 PM THIS EVENING TO 10 AM EST SUNDAY FOR PAZ001>003. MARINE...NONE. && $$ SYNOPSIS...KEC NEAR TERM...KEC/KIELTYKA SHORT TERM...KEC LONG TERM...LAPLANTE AVIATION...LOMBARDY MARINE...BC/LAPLANTE
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
432 PM EST SAT JAN 25 2014 .SYNOPSIS... A COLD FRONT WILL PUSH SOUTH OF THE AREA TONIGHT. HIGH PRESSURE WILL BUILD EAST ACROSS THE OHIO VALLEY LATE TONIGHT INTO EARLY SUNDAY. THE NEXT CLIPPER WILL SLIDE SOUTHEAST ACROSS THE GREAT LAKES ON SUNDAY. THE NEXT PUSH OF ARCTIC AIR WILL ARRIVE BEHIND THIS SYSTEM AS ARCTIC HIGH PRESSURE BUILDS TOWARDS THE OHIO VALLEY THROUGH MID-WEEK. && .NEAR TERM /UNTIL 6 AM SUNDAY MORNING/... WINTER WEATHER ADVISORIES REMAIN IN EFFECT UNTIL 10 PM. SNOW SQUALLS HAVE INTENSIFIED ACROSS NORTHEAST OHIO SINCE 1 PM AS THE COLD FRONT MOVES SOUTHEAST ACROSS THE AREA AND THE UPPER LEVEL TROUGH BEARS DOWN UPON US. THERE IS A CONVECTIVE COMPONENT TO THE SNOW SQUALLS AS THE COLD POOL ALOFT ARRIVES. SNOW MAY BE HEAVY AT TIMES THROUGH 7 PM...BUT THE TREND WILL BE TO PUSH INLAND INTO THIS EVENING AND WEAKEN AS THE SURFACE TROUGH PUSHES SOUTH. 1000-850MB OMEGA HAS BEEN DOING A GOOD JOB HIGHLIGHTING THIS THREAT AND BOTH THE NAM12 AND RUC13 SHOWS THE PEAK HAS OCCURRED. CONSIDERED CANCELLING THE ADVISORY IN NW OHIO BUT THERE IS SOME CONCERN THAT THE LAKE ENHANCED SNOW BANDS OVER NRN INDIANA WILL SPREAD INTO NW OHIO AS THE RIDGE BUILDS TO OUR SOUTH. ACCUMULATIONS WILL BE MINOR...AN INCH OR LOCALLY UP TO 2...BUT MOST AREAS WILL BE BELOW AN INCH. WINDS REMAIN GUSTY ENOUGH HOWEVER THAT THOUGHT IT WAS WORTH CONTINUING FOR A FEW MORE HOURS. WINDS WILL SHIFT TO THE WEST AND DECREASE THROUGH THE NIGHT TO AROUND 8-12 MPH BY MORNING. A WIND CHILL ADVISORY HAS BEEN ISSUED FOR THE WHOLE AREA STARTING AFTER 10 PM AS THE NEXT PUSH OF REALLY COLD AIR ARRIVES. && .SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY NIGHT/... SOUTHWEST FLOW WILL BRING THE NEXT ROUND OF WARM ADVECTION SNOW AHEAD OF THE CLIPPER THAT WILL MOVE ACROSS THE CENTRAL GREAT LAKES ON SUNDAY. SNOWFALL MAY BE AS HIGH AS 2-3 INCHES IN OUR SOUTHWESTERN COUNTIES BUT WILL ONCE AGAIN COMBINE WITH BRISK WIND TO CREATE BLOWING SNOW CONCERNS...ESPECIALLY IN NW OHIO WHERE THE LANDSCAPE IS MORE OPEN. ELSEWHERE SNOW WILL BE LESS THAN 2 INCHES. A WINTER WEATHER ADVISORY MAY BE NEEDED FOR AREAS FROM TOLEDO TO MOUNT VERNON BUT WANTED TO KEEP IT SEPARATE FROM THE CURRENT HEADLINES AS THERE WILL BE A SIZEABLE BREAK IN THE SNOW. TEMPERATURES WILL WARM ON SUNDAY AS WE GET INTO THE WARM SECTOR WITH HIGHS RANGING FROM THE UPPER TEENS IN NW PA TO UPPER 2OS IN NORTH CENTRAL OHIO. THE ASSOCIATED ARCTIC COLD FRONT PUSHES BACK SOUTH LATE SUNDAY NIGHT AND TEMPERATURES WILL FALL THROUGH THE DAY ON MONDAY. BY MONDAY NIGHT LOWS WILL FALL TO AROUND -5 DEGREES NEAR LAKE ERIE AND -10 TO -15 DEGREES INLAND. THIS WILL RESULT IN DANGEROUSLY COLD WIND CHILL VALUES NEAR -25 AND WILL BE ON THE FRINGE OF NEEDING EITHER A WIND CHILL ADVISORY OR WARNING. && .LONG TERM /TUESDAY THROUGH SATURDAY/... THE UPPER LEVEL PATTERN WILL REMAIN PRETTY MUCH UNCHANGED THROUGHOUT THE EXTENDED FORECAST PERIOD...HOWEVER BY THE END OF THE EXTENDED PERIOD LATE FRIDAY INTO NEXT WEEKEND LOOK FOR A SOUTHERLY FLOW TO PUSH TEMPERATURES POSSIBLY INTO THE UPPER 20S AND 30S. STILL COLD AND RAW TUESDAY WITH DAYTIME TEMPERATURES STRUGGLING TO GET INTO THE DOUBLE DIGITS. SLIGHTLY WARMER THURSDAY WITH HIGHS IN THE TEENS TO AROUND 20 AND SLIGHT WARM-UP FRIDAY WITH HIGHS IN THE 20S. WITH TEMPERATURES IN THE 20S FRIDAY THIS IS STILL ALMOST TEN DEGREES BELOW NORMAL FOR THIS TIME OF YEAR. && .AVIATION /18Z SATURDAY THROUGH THURSDAY/... THE ARCTIC COLD FRONT FROM THE WESTERN TIP OF LAKE ERIE TO SOUTHERN INDIANA WILL CONTINUE TO SWEEP EAST ALONG WITH A BAND OF SYNOPTIC SNOW WITH IFR VSYS AND MVFR CIGS. SCATTERED LAKE EFFECT SNOW SHOWERS FROM LAKES MICHIGAN AND HURON ARE STREAMING OFF THOSE LAKES ACROSS LOWER MICHIGAN AND INTO OHIO AND NORTHERN INDIANA. SO STILL EXPECT SCATTERED SNOW SHOWERS TO BRIEFLY LOWER VSBY BELOW 3 MILES. THIS ACTIVITY WILL DIMINISH TOWARD SUNSET. SOUTHWEST WINDS OVER THE EASTERN TAFS WILL BECOME NORTHWEST AFTER THE FRONTAL PASSAGE. FAIRLY QUIET CONDITIONS ARE EXPECTED TONIGHT WITH A FEW LINGERING SNOW SHOWERS MAINLY FROM CLE EAST TO ERI IN THE SNOWBELT. TOWARD MORNING ISENTROPIC LIFT ASSOCIATED WITH AN APPROACHING WARM FRONT WILL SPREAD INTO THE REGION FROM THE WEST AND ANOTHER AREA OF SNOW WILL MOVE INTO THE REGION AFTER 12Z. CIGS AND VSBY WILL QUICKLY DROP TO IFR CONDITIONS. THE AREA WILL BE BRIEFLY IN THE WARM SECTOR SUNDAY EVENING UNTIL ANOTHER ARCTIC COLD FRONT SWEEPS THROUGH THROUGH REGION. A BAND OF SNOW WILL LIKELY ACCOMPANY THIS FEATURE WITH MVFR TO IFR CONDITIONS. OUTLOOK...NON VFR INTO MONDAY. NON VFR MAINLY IN THE SNOW BELT MONDAY NIGHT INTO TUESDAY. && .MARINE... WILL CONTINUE GALE WARNING TIL 10 AM THIS MORNING AFTER COORDINATING WITH WFO BUF. WINDS WILL REMAIN FAIRLY GUSTY THROUGH TODAY WITH SOUTHWEST WINDS TO 30 TO 35 KNOTS BECOMING WESTERLY. ANOTHER WEATHER DISTURBANCE WILL BRING A CHANCE OF ANOTHER GALE SUNDAY NIGHT BUT WILL HOLD THE LINE TO RIGHT BELOW GALE CRITERIA AT THIS TIME. BEHIND THIS WEATHER SYSTEM LOOK FOR WEST TO SOUTHWEST WIND FLOW MONDAY INTO TUESDAY. WAVES WILL BE OMITTED DUE TO THE LAKE BEING MOSTLY ICE COVERED. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...WINTER WEATHER ADVISORY UNTIL 10 PM EST THIS EVENING FOR OHZ003-006>014-017>023-027>033-036>038-047-089. WIND CHILL ADVISORY FROM 10 PM THIS EVENING TO 10 AM EST SUNDAY FOR OHZ009>014-019>023-029>033-038-089. WIND CHILL ADVISORY FROM 10 PM THIS EVENING TO 7 AM EST SUNDAY FOR OHZ003-006>008-017-018-027-028-036-037-047. PA...WINTER WEATHER ADVISORY UNTIL 10 PM EST THIS EVENING FOR PAZ001>003. WIND CHILL ADVISORY FROM 10 PM THIS EVENING TO 10 AM EST SUNDAY FOR PAZ001>003. MARINE...NONE. && $$ SYNOPSIS...KEC NEAR TERM...KEC SHORT TERM...KEC LONG TERM...LAPLANTE AVIATION...LAPLANTE MARINE...BC/LAPLANTE
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
126 PM EST SAT JAN 25 2014 .SYNOPSIS... A COLD FRONT OVER THE WESTERN GREAT LAKES WILL MOVE ACROSS THE LOCAL AREA TODAY. A FAST MOVING LOW PRESSURE SYSTEM WILL MOVE ACROSS THE CENTRAL GREAT LAKES ON SUNDAY AND DRAG AN ARCTIC COLD FRONT ACROSS THE REGION SUNDAY NIGHT. ARCTIC HIGH PRESSURE WILL THEN BUILD OVER THE REGION FROM THE WEST THE FIRST HALF OF THE WORKWEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... REGIONAL RADARS SHOW THE CLEARING AREA BEHIND THE WIDESPREAD SNOW HAS MADE IT TO A LINE FROM NORWALK TO MARION BY 11 AM. THE CLEARING IS OCCURRING AS MID-LEVEL DRY AIR SPREADS IN FROM THE WEST AS CLEARLY SEEN ON WATER VAPOR IMAGERY. THIS HOWEVER IS NOT THE END TO THE SNOW AS A HEAVY BURST OF SNOW IS ACCOMPANYING THE COLD FRONT WITH SCATTERED TO NUMEROUS SNOW SHOWERS BEHIND THE FRONT. VISIBILITIES AT MOST SITES ARE DROPPING TO A QUARTER MILE OR LESS WITH THE SNOW ALONG THE FRONT IN SE MICHIGAN. THE FRONT HAS JUST REACHED DETROIT AND WILL PUSH INTO NW OHIO SOON. THE NAM AND RUC ARE BOTH PARTICULARLY ENERGETIC WITH LOW LEVEL OMEGA WITH THE FRONTAL PASSAGE THIS AFTERNOON SO CONTINUED TO CARRY ABOUT AN INCH OF ADDITIONAL SNOW IN NW OHIO...WITH 1 TO LOCALLY 3 INCHES IN NE OHIO/NW PA. THE FRESH SNOW WILL CONTINUE TO BLOW AROUND AS WINDS GUST TO 30 MPH. THE AREAS THAT ARE BEING EFFECT BY BLOWING SNOW THIS MORNING MAY CHANGE AS THE WIND SHIFTS TO NORTHWEST BEHIND THE FRONT. ORIGINAL...THE SNOW HAS ARRIVED WITH WIDESPREAD VISIBILITIES OF 1 TO 2 MILES. THIS IS GOOD FOR A COUPLE TENTHS OF ACCUMULATION PER HOUR. S TO SW FLOW CONTINUES TO BE VERY GUSTY BUT PEAK GUSTS HAVE ALREADY STARTED TO GO DOWN. WILL LIKELY SEE GUSTS TO 35 MPH FOR A COUPLE MORE HOURS WITH WINDS PEAKING IN THE 25 TO 30 MPH RANGE BY MID MORNING. SATELLITE SHOWING SOME DRYING MOVING INTO NW OH AND SURFACE VSBYS HAVE IMPROVED. HEAVIER SNOW OVER NORTHERN INDIANA COMING FROM LAKE MI SHOULD MOVE BACK OVER THE AREA TOWARD DAYBREAK. IT APPEARS THE SNOW WILL QUICKLY DIMINISH FROM WEST TO EAST LATER THIS MORNING. WITH ALL OF THIS IN MIND...WILL KEEP THE ADVISORIES GOING AS IS BUT WILL BACK OFF ON SNOW TOTALS SOME. MUCH OF THE AREA WILL END UP WITH A TOTAL OF 2 TO 4 INCHES WITH JUST LOCALLY HIGHER AMOUNTS. THE WINDS WILL BE THE BIG STORY AND EXPECT A LOT OF BLOWING AND DRIFTING. LOT`S OF WARMER AIR JUST TO THE WEST BUT THINK TEMPS ARE ABOUT DONE CLIMBING NOW THAT THE SNOW HAS ARRIVED. && .SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/... THE COLD FRONT WILL BE THROUGH BY THE START OF TONIGHT LEAVING ONLY SOME SNOW SHOWERS BEHIND. EXPECT THE W TO NW FLOW BEHIND THE FRONT TO ONLY GRADUALLY DIMINISH OVERNIGHT. SUSPECT THAT WE WILL NEED A WIND CHILL ADVISORY AGAIN FOR TONIGHT BUT WILL LET DAY CREW TAKE CARE OF THAT ONCE THE SNOW SETTLES DOWN. EXPECT THAT THE STRONG WINDS OVERNIGHT HAVE SHIFTED THE ICE FIELDS ON LAKE ERIE AROUND. WILL LIKELY SEE SOME LAKE ENHANCED SNOW SHOWERS EAST OF KCLE BUT BRIEF RIDGING WILL MAKE THE FLOW UNFAVORABLE BY SUNDAY MORNING. HAVE SLOWED THE ONSET OF THE SNOW FROM THE NEXT CLIPPER DOWN A FEW HOURS GIVEN NEW 00Z GUIDANCE. IT WILL BE AFTERNOON BEFORE THE EAST 2/3 OF THE AREA GETS ANY SNOW. LOOKING LIKE A 1 TO 3 INCH TYPE SYSTEM SO DO NOT THINK WE WILL NEED MORE HEADLINES. EXPECT THE SNOW TO DIMINISH QUICKLY SUNDAY EVENING. WILL OF COURSE HAVE TO DEAL WITH THE THREAT OF LAKE EFFECT MONDAY INTO TUESDAY. SOME LAKE EFFECT FROM LAKE MICHIGAN COULD SNEAK INTO NW AND N CENTRAL OH ON SUNDAY NIGHT INTO MONDAY. WILL GO WITH HIGHER THAN NORMAL POPS FOR THOSE AREAS. AFTER THAT THE ARCTIC AIRMASS SETS UP OVER THE REGION. 850 MB TEMPS COULD AGAIN GET CLOSE TO NEG 30. HAVE NOT MADE MANY TEMPS CHANGES TO THE SECOND HALF OF THE PERIOD. WILL HAVE TO WAIT TO SEE WHAT CLOUDS AND WINDS DO BEFORE MAKING ANY BIG CHANGES. && .LONG TERM /WEDNESDAY THROUGH FRIDAY/... THE UPPER LEVEL PATTERN WILL REMAIN PRETTY MUCH UNCHANGED THROUGHOUT THE EXTENDED FORECAST PERIOD...HOWEVER BY THE END OF THE EXTENDED PERIOD LATE FRIDAY INTO NEXT WEEKEND LOOK FOR A SOUTHERLY FLOW TO PUSH TEMPERATURES POSSIBLY INTO THE UPPER 20S AND 30S. STILL COLD AND RAW TUESDAY WITH DAYTIME TEMPERATURES STRUGGLING TO GET INTO THE DOUBLE DIGITS. SLIGHTLY WARMER THURSDAY WITH HIGHS IN THE TEENS TO AROUND 20 AND SLIGHT WARM-UP FRIDAY WITH HIGHS IN THE 20S. WITH TEMPERATURES IN THE 20S FRIDAY THIS IS STILL ALMOST TEN DEGREES BELOW NORMAL FOR THIS TIME OF YEAR. && .AVIATION /18Z SATURDAY THROUGH THURSDAY/... THE ARCTIC COLD FRONT FROM THE WESTERN TIP OF LAKE ERIE TO SOUTHERN INDIANA WILL CONTINUE TO SWEEP EAST ALONG WITH A BAND OF SYNOPTIC SNOW WITH IFR VSYS AND MVFR CIGS. SCATTERED LAKE EFFECT SNOW SHOWERS FROM LAKES MICHIGAN AND HURON ARE STREAMING OFF THOSE LAKES ACROSS LOWER MICHIGAN AND INTO OHIO AND NORTHERN INDIANA. SO STILL EXPECT SCATTERED SNOW SHOWERS TO BRIEFLY LOWER VSBY BELOW 3 MILES. THIS ACTIVITY WILL DIMINISH TOWARD SUNSET. SOUTHWEST WINDS OVER THE EASTERN TAFS WILL BECOME NORTHWEST AFTER THE FRONTAL PASSAGE. FAIRLY QUIET CONDITIONS ARE EXPECTED TONIGHT WITH A FEW LINGERING SNOW SHOWERS MAINLY FROM CLE EAST TO ERI IN THE SNOWBELT. TOWARD MORNING ISENTROPIC LIFT ASSOCIATED WITH AN APPROACHING WARM FRONT WILL SPREAD INTO THE REGION FROM THE WEST AND ANOTHER AREA OF SNOW WILL MOVE INTO THE REGION AFTER 12Z. CIGS AND VSBY WILL QUICKLY DROP TO IFR CONDITIONS. THE AREA WILL BE BRIEFLY IN THE WARM SECTOR SUNDAY EVENING UNTIL ANOTHER ARCTIC COLD FRONT SWEEPS THROUGH THROUGH REGION. A BAND OF SNOW WILL LIKELY ACCOMPANY THIS FEATURE WITH MVFR TO IFR CONDITIONS. OUTLOOK...NON VFR INTO MONDAY. NON VFR MAINLY IN THE SNOW BELT MONDAY NIGHT INTO TUESDAY. && .MARINE... WILL CONTINUE GALE WARNING TIL 10 AM THIS MORNING AFTER COORDINATING WITH WFO BUF. WINDS WILL REMAIN FAIRLY GUSTY THROUGH TODAY WITH SOUTHWEST WINDS TO 30 TO 35 KNOTS BECOMING WESTERLY. ANOTHER WEATHER DISTURBANCE WILL BRING A CHANCE OF ANOTHER GALE SUNDAY NIGHT BUT WILL HOLD THE LINE TO RIGHT BELOW GALE CRITERIA AT THIS TIME. BEHIND THIS WEATHER SYSTEM LOOK FOR WEST TO SOUTHWEST WIND FLOW MONDAY INTO TUESDAY. WAVES WILL BE OMITTED DUE TO THE LAKE BEING MOSTLY ICE COVERED. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...WINTER WEATHER ADVISORY UNTIL 10 PM EST THIS EVENING FOR OHZ003-006>014-017>023-027>033-036>038-047-089. PA...WINTER WEATHER ADVISORY UNTIL 10 PM EST THIS EVENING FOR PAZ001>003. MARINE...NONE. && $$ SYNOPSIS...KUBINA NEAR TERM...KEC/KUBINA SHORT TERM...KUBINA LONG TERM...BC AVIATION...LAPLANTE MARINE...BC
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
1138 AM EST SAT JAN 25 2014 .SYNOPSIS... A COLD FRONT OVER THE WESTERN GREAT LAKES WILL MOVE ACROSS THE LOCAL AREA TODAY. A FAST MOVING LOW PRESSURE SYSTEM WILL MOVE ACROSS THE CENTRAL GREAT LAKES ON SUNDAY AND DRAG AN ARCTIC COLD FRONT ACROSS THE REGION SUNDAY NIGHT. ARCTIC HIGH PRESSURE WILL THEN BUILD OVER THE REGION FROM THE WEST THE FIRST HALF OF THE WORKWEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... REGIONAL RADARS SHOW THE CLEARING AREA BEHIND THE WIDESPREAD SNOW HAS MADE IT TO A LINE FROM NORWALK TO MARION BY 11 AM. THE CLEARING IS OCCURRING AS MID-LEVEL DRY AIR SPREADS IN FROM THE WEST AS CLEARLY SEEN ON WATER VAPOR IMAGERY. THIS HOWEVER IS NOT THE END TO THE SNOW AS A HEAVY BURST OF SNOW IS ACCOMPANYING THE COLD FRONT WITH SCATTERED TO NUMEROUS SNOW SHOWERS BEHIND THE FRONT. VISIBILITIES AT MOST SITES ARE DROPPING TO A QUARTER MILE OR LESS WITH THE SNOW ALONG THE FRONT IN SE MICHIGAN. THE FRONT HAS JUST REACHED DETROIT AND WILL PUSH INTO NW OHIO SOON. THE NAM AND RUC ARE BOTH PARTICULARLY ENERGETIC WITH LOW LEVEL OMEGA WITH THE FRONTAL PASSAGE THIS AFTERNOON SO CONTINUED TO CARRY ABOUT AN INCH OF ADDITIONAL SNOW IN NW OHIO...WITH 1 TO LOCALLY 3 INCHES IN NE OHIO/NW PA. THE FRESH SNOW WILL CONTINUE TO BLOW AROUND AS WINDS GUST TO 30 MPH. THE AREAS THAT ARE BEING EFFECT BY BLOWING SNOW THIS MORNING MAY CHANGE AS THE WIND SHIFTS TO NORTHWEST BEHIND THE FRONT. ORIGINAL...THE SNOW HAS ARRIVED WITH WIDESPREAD VISIBILITIES OF 1 TO 2 MILES. THIS IS GOOD FOR A COUPLE TENTHS OF ACCUMULATION PER HOUR. S TO SW FLOW CONTINUES TO BE VERY GUSTY BUT PEAK GUSTS HAVE ALREADY STARTED TO GO DOWN. WILL LIKELY SEE GUSTS TO 35 MPH FOR A COUPLE MORE HOURS WITH WINDS PEAKING IN THE 25 TO 30 MPH RANGE BY MID MORNING. SATELLITE SHOWING SOME DRYING MOVING INTO NW OH AND SURFACE VSBYS HAVE IMPROVED. HEAVIER SNOW OVER NORTHERN INDIANA COMING FROM LAKE MI SHOULD MOVE BACK OVER THE AREA TOWARD DAYBREAK. IT APPEARS THE SNOW WILL QUICKLY DIMINISH FROM WEST TO EAST LATER THIS MORNING. WITH ALL OF THIS IN MIND...WILL KEEP THE ADVISORIES GOING AS IS BUT WILL BACK OFF ON SNOW TOTALS SOME. MUCH OF THE AREA WILL END UP WITH A TOTAL OF 2 TO 4 INCHES WITH JUST LOCALLY HIGHER AMOUNTS. THE WINDS WILL BE THE BIG STORY AND EXPECT A LOT OF BLOWING AND DRIFTING. LOT`S OF WARMER AIR JUST TO THE WEST BUT THINK TEMPS ARE ABOUT DONE CLIMBING NOW THAT THE SNOW HAS ARRIVED. && .SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/... THE COLD FRONT WILL BE THROUGH BY THE START OF TONIGHT LEAVING ONLY SOME SNOW SHOWERS BEHIND. EXPECT THE W TO NW FLOW BEHIND THE FRONT TO ONLY GRADUALLY DIMINISH OVERNIGHT. SUSPECT THAT WE WILL NEED A WIND CHILL ADVISORY AGAIN FOR TONIGHT BUT WILL LET DAY CREW TAKE CARE OF THAT ONCE THE SNOW SETTLES DOWN. EXPECT THAT THE STRONG WINDS OVERNIGHT HAVE SHIFTED THE ICE FIELDS ON LAKE ERIE AROUND. WILL LIKELY SEE SOME LAKE ENHANCED SNOW SHOWERS EAST OF KCLE BUT BRIEF RIDGING WILL MAKE THE FLOW UNFAVORABLE BY SUNDAY MORNING. HAVE SLOWED THE ONSET OF THE SNOW FROM THE NEXT CLIPPER DOWN A FEW HOURS GIVEN NEW 00Z GUIDANCE. IT WILL BE AFTERNOON BEFORE THE EAST 2/3 OF THE AREA GETS ANY SNOW. LOOKING LIKE A 1 TO 3 INCH TYPE SYSTEM SO DO NOT THINK WE WILL NEED MORE HEADLINES. EXPECT THE SNOW TO DIMINISH QUICKLY SUNDAY EVENING. WILL OF COURSE HAVE TO DEAL WITH THE THREAT OF LAKE EFFECT MONDAY INTO TUESDAY. SOME LAKE EFFECT FROM LAKE MICHIGAN COULD SNEAK INTO NW AND N CENTRAL OH ON SUNDAY NIGHT INTO MONDAY. WILL GO WITH HIGHER THAN NORMAL POPS FOR THOSE AREAS. AFTER THAT THE ARCTIC AIRMASS SETS UP OVER THE REGION. 850 MB TEMPS COULD AGAIN GET CLOSE TO NEG 30. HAVE NOT MADE MANY TEMPS CHANGES TO THE SECOND HALF OF THE PERIOD. WILL HAVE TO WAIT TO SEE WHAT CLOUDS AND WINDS DO BEFORE MAKING ANY BIG CHANGES. && .LONG TERM /WEDNESDAY THROUGH FRIDAY/... THE UPPER LEVEL PATTERN WILL REMAIN PRETTY MUCH UNCHANGED THROUGHOUT THE EXTENDED FORECAST PERIOD...HOWEVER BY THE END OF THE EXTENDED PERIOD LATE FRIDAY INTO NEXT WEEKEND LOOK FOR A SOUTHERLY FLOW TO PUSH TEMPERATURES POSSIBLY INTO THE UPPER 20S AND 30S. STILL COLD AND RAW TUESDAY WITH DAYTIME TEMPERATURES STRUGGLING TO GET INTO THE DOUBLE DIGITS. SLIGHTLY WARMER THURSDAY WITH HIGHS IN THE TEENS TO AROUND 20 AND SLIGHT WARM-UP FRIDAY WITH HIGHS IN THE 20S. WITH TEMPERATURES IN THE 20S FRIDAY THIS IS STILL ALMOST TEN DEGREES BELOW NORMAL FOR THIS TIME OF YEAR. && .AVIATION /12Z SATURDAY THROUGH WEDNESDAY/... A CLIPPER SYSTEM WILL CROSS MOST OF THE AREA BY THIS AFTERNOON. THIS SYSTEM HAS SPREAD SNOW ACROSS THE ENTIRE FORECAST AREA AND WILL CONTINUE INTO THIS AFTERNOON. THE STRONG WESTERLY WINDS WILL BRING PLENTY OF BLOWING AND DRIFTING SNOW. ONCE THE FRONT MOVES THROUGH THE AREA...CONDITIONS WILL IMPROVE SOME EXCEPT FOR SOME BLOWING SNOW AND THEN SOME LAKE ENHANCED SNOW FOR THE SNOW BELT AREAS. OUTLOOK...NON VFR MAINLY IN THE SNOW BELT LATE TONIGHT. NON VFR REDEVELOPING OVER THE ENTIRE AREA SUNDAY AND CONTINUING INTO MONDAY. NON VFR MAINLY IN THE SNOW BELT MONDAY NIGHT INTO TUESDAY. && .MARINE... WILL CONTINUE GALE WARNING TIL 10 AM THIS MORNING AFTER COORDINATING WITH WFO BUF. WINDS WILL REMAIN FAIRLY GUSTY THROUGH TODAY WITH SOUTHWEST WINDS TO 30 TO 35 KNOTS BECOMING WESTERLY. ANOTHER WEATHER DISTURBANCE WILL BRING A CHANCE OF ANOTHER GALE SUNDAY NIGHT BUT WILL HOLD THE LINE TO RIGHT BELOW GALE CRITERIA AT THIS TIME. BEHIND THIS WEATHER SYSTEM LOOK FOR WEST TO SOUTHWEST WIND FLOW MONDAY INTO TUESDAY. WAVES WILL BE OMITTED DUE TO THE LAKE BEING MOSTLY ICE COVERED. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...WINTER WEATHER ADVISORY UNTIL 10 PM EST THIS EVENING FOR OHZ003-006>014-017>023-027>033-036>038-047-089. PA...WINTER WEATHER ADVISORY UNTIL 10 PM EST THIS EVENING FOR PAZ001>003. MARINE...NONE. && $$ SYNOPSIS...KUBINA NEAR TERM...KEC/KUBINA SHORT TERM...KUBINA LONG TERM...BC AVIATION...BC MARINE...BC
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
449 PM EST SAT JAN 25 2014 .SYNOPSIS... AN ANOMALOUS UPPER LEVEL TROUGH WILL REMAIN ENTRENCHED OVER THE REGION FOR THE NEXT SEVERAL DAYS...WITH VERY COLD/BELOW NORMAL TEMPERATURES CONTINUING TO IMPACT CENTRAL PENNSYLVANIA THROUGH THE END OF THE MONTH. && .NEAR TERM /UNTIL 6 AM SUNDAY MORNING/... LIGHT SNOW HAS FINALLY BEGUN AT ALTOONA AND STATE COLLEGE AS DOWNSLOPING DOES FINE WORK IN RETARDING THE EASTWARD PROGRESS OF THE SNOW SHIELD ASSOCIATED WITH THE WARM ADVECTION AHEAD OF OUR APPROACHING COLD FRONT. MESO ANAL SHOWS THE COLD FRONT ENTERING NW OHIO AS OF 17Z...WITH A VERY HARD TO FIND WARM FRONT SNAKING UP THRU SERN PA. THIS FEATURE SHOWS UP BEST IN THE LOW LEVEL LI FIELD...BUT TEMP AND WIND CHANGES ACROSS THE BOUNDARY ARE SUBTLE AT BEST. STABILITY IS ERODING AHEAD OF THE FRONT THROUGH OHIO...BUT AS YET THERE ARE NO SIGNS OF THE KIND OF SQUALL LINE THE HIGH RES WRF HAS BEEN ADVERTISING. THE 16Z RAP DOESN`T SHOW A COHERENT LINE ADVANCING THRU CENTRAL PA...JUST SOME SCATTERED SNOW SHOWERS FOR THE MOST PART. THE OTHER NOTEWORTHY ASPECT OF THE WEATHER MOVING OUR WAY WILL BE THE INCREASINGLY GUSTY WIND AND INVADING COLD. UPSTREAM WINDS ARE RUNNING 25-35MPH...COMBINED WITH EXPECTED LOWS IN THE SINGLE DIGITS TO BELOW ZERO OVER THE NORTH...WILL CREATE WIND CHILLS BELOW ZERO IN MOST AREAS BY MORNING. HAVE DECIDED TO REMAIN WITH THE CURRENT ADVISORY CONFIGURATION AS MODELS ARE CONSISTENT IN SHOWING OUR WESTERN ZONES SEEING SEVERAL INCHES OF SNOW...AS WELL A SECONDARY AREA OVER THE HIGHER ELEVATIONS OF THE EAST WHERE SOME UPSLOPE COMBINES WITH THE WARM ADVECTION TO BRING SLIGHTLY HIGHER AMOUNTS. RATIOS WILL BE MORE IMPORTANT THERE SO CONFIDENCE IS LOWER...BUT NOT LOW ENOUGH TO CANCEL THE ADVISORY. THE FRONT SHOULD BE OFFSHORE BY MIDNIGHT..LEAVING A COLDER NW FLOW OVER THE AREA. THIS SHOULD CONFINE THE REMAINDER OF THE SNOW-SHOWER ACTIVITY TO THE UPSLOPE AREAS OF THE WEST AND NORTH...BUT WITH LAKE ERIE BEING ALMOST TOTALLY FROZEN...LAKE EFFECT WILL NOT BE A SIGNIFICANT CONTRIBUTOR TO THE MOISTURE AND PRECIP. && .SHORT TERM /6 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/... ONLY THE BRIEFEST OF RESPITES IS IN STORE FOR THE REGION EARLY SUNDAY AS THE FIRST CLIPPER DEPARTS...AND THE NEXT IN THE WAVE TRAIN APPROACHES. AT THIS POINT TIMING WOULD SUGGEST A DRY MORNING GIVING WAY TO THICKENING CLOUDS AND LIGHT SNOW MOVING INTO AT LEAST MY WESTERN ZONES BY MID TO LATE AFTERNOON. MOISTURE WILL BE TYPICALLY LIMITED WITH THE NEXT WAVE...AND INSTABILITY IS NOT ADVERTISED TO BE ESPECIALLY IMPRESSIVE...SO SNOW AMOUNTS WILL REMAIN LIGHT TO INSIGNIFICANT IN MOST AREAS. && .LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/... THIS ABOVE NOTED CLIPPER WILL BRING ANOTHER WILD TEMPERATURE SWING...FROM SLOWLY RISING TEMPS LATE SUNDAY THROUGH SUNDAY NIGHT /WHICH MAY BRING THE WARMEST READINGS OF THE ENTIRE WEEK TO MANY LOCALES AROUND SUNRISE MONDAY/...FOLLOWED BY A PLUNGE IN THE MERCURY THROUGH THE DAY MONDAY INTO EARLY TUESDAY BEHIND THE TRAILING COLD FROND AS VERY COLD ARCTIC AIR AGAIN GRIPS THE REGION THROUGH MIDWEEK. PERIODS OF MAINLY LIGHT SNOW OR SNOW SHOWERS WILL COINCIDE WITH THE PASSAGE OF THE UPPER LEVEL SHORT WAVE AND SFC CFRONT. 03Z SREF SHOWS QUITE GOOD CLUSTERING OF PLUMES BETWEEN 0.10 AND 0.25 LEQ ACROSS THE NW HALF OF THE CWA LATE SUNDAY THROUGH THE MID MORNING HOURS MONDAY...WHILE LOCATIONS FURTHER TO THE SOUTHEAST HAVE SREF MEAN LIQUID EQUIVALENT QPF OF LESS THAN 0.10. ACCUMS OF A COATING TO 2 INCHES ARE LIKELY...ACROSS CENTRAL PENN. THE POTENTIAL EXISTS FOR ANOTHER/SIMILAR ROUND OF ADVISORY CRITERIA 2-4 INCH SNOW OVER THE NW MTNS AND LAURELS...PRECEDING ANY OROGRAPHIC/LES SNOW SHOWERS/LOCALIZED SQUALLS THAT OCCURS IN THE WAKE OF THE COLD FRONT MONDAY AND MONDAY NIGHT. MEDIUM RANGE OPERATIONAL GUIDANCE AND ENSEMBLES INDICATE THAT WE COULD SEE VERY SIMILAR TEMPS TO WHAT WE EXPERIENCED DURING THE EARLY JANUARY...RECORD COLD OUTBREAK. MODEL GUIDANCE ALMOST UNANIMOUSLY BRINGS LOW TEMPS BELOW ZERO TO ENTIRE CWA TUE AND WED MORNING...WITH -10F OR COLDER IN THE NORTHERN MTNS AND LAUREL HIGHLANDS. TUESDAY WILL BRING THE COLDEST HIGHS OF THE WEEK...AS TEMPS MAY STRUGGLE TO GET ABOVE ZERO ACROSS THE HIGHER ELEVATIONS...AND INCH ONLY INTO THE MID TEENS IN THE SE. THERE/S HIGH CONFIDENCE THAT WE/LL SEE WIDESPREAD WIND CHILL ADVISORY CRITERIA /OF -15F/ BEING MET LATE MONDAY NIGHT THROUGH WEDNESDAY /WITH A SEEMINGLY HIGH POTENTIAL FOR WARNING CRITERIA OF -25F ACROSS HIGHER TERRAIN OF THE NORTH AND WEST MAINLY MON NIGHT INTO TUE WITH BREEZY CONDITIONS. LIGHTER WINDS FOR WED WILL LIKELY PRECLUDE WC WARNINGS...BUT EVEN A LIGHT BREEZE WILL BRING WIND CHILLS BACK BELOW -15 TUE NIGHT INTO WED...WITH COLDER TEMP READINGS POSS AS THE WINDS LIGHTEN AND SKIES POTENTIALLY CLEAR OUT WITH HIGH PRESSURE RIDGING IN FROM THE WEST. ANY SNOW SHOWERS AND LIGHT TO MDT ACCUMS /MONDAY NIGHT INTO WEDNESDAY/ SHOULD BE STRICTLY CONFINED TO THE FAR NW ZONES...AND PERHAPS THE RIDGES OF WRN SOMERSET/CAMBRIA COUNTIES. OTHER THAN THE BITTER COLD /TEMPS ABOUT 20F BELOW NORMAL/ THE MID-LATE WEEK WEATHER WILL BE OVERALL QUIET AS SURFACE HIGH PRESSURE RIDGE SETTLES IN. FLOW TURNS MORE SW HEADING INTO THE WEEKEND...WHICH WILL BRING A GRADUAL WARMING TREND BACK TOWARD ONLY 5-10F BELOW NORMAL. THIS TREND IS LIKELY TO CONTINUE INTO NEXT WEEK AS MODEL AND ENSEMBLE GUIDANCE SUGGESTS THE VERY AMPLIFIED ERN TROUGH PATTERN BEGINS TO RELAX AS THE STRONG WEST COAST RIDGE FINALLY BREAKS DOWN...WHICH SHOULD BRING RELIEF FROM THE BITTER COLD AS WE ENTER INTO FEBRUARY. && .AVIATION /22Z SATURDAY THROUGH THURSDAY/... NOT MUCH IN THE EAST YET AT SPOTS LIKE MDT AND LNS. SOME PATCHY SNOW ACROSS THE UNV...AOO AREAS. MAIN CONCERN IS LINE OF HEAVY SNOW SHOWERS AND SQUALLS JUST ENTERING NW PA. ADJUSTED 21Z TAFS FOR THIS. EARLIER DISCUSSION BELOW. SNOW OVER WESTERN HIGH TERRAIN TERMINALS WILL KEEP IFR CONDITIONS INTO THE EVENING WHEN GRADUAL IMPROVEMENT WILL DEVELOP AS A COLD FRONT MOVES THROUGH THE AREA AND BRINGS A WIND SHIFT AND COLDER- DRIER AIR FOR THE REMAINDER OF THE OVERNIGHT INTO THE FIRST PART OF SUNDAY. OVER CENTRAL AND EASTERN AREAS...OCNL MVFR/IFR IN THE LIGHT SNOW WITH VISIBILITY BEING THE MAIN ISSUE...AVERAGING 1-3 MILES IN THE LIGHT SNOW. SIMILAR TO WESTERN AREAS...CONDITIONS WILL IMPROVE OVERNIGHT IN THE POST FRONTAL ENVIRONMENT. THE WIND WILL SHIFT AND BE GUSTY OUT OF THE WNW OVERNIGHT...WITH GUSTS OF 25-30KT COMMON...ESPECIALLY OVER THE RIDGES. THIS WILL CREATE ISSUES WITH BLOWING SNOW WHERE ACCUM SNOW HAS OCCURRED TODAY...MAINLY OVER WESTERN AND NORTHERN AREAS. A NEW SYSTEM APPROACHING SUNDAY WILL BRING MORE LIGHT SNOW AND FLIGHT RESTRICTIONS WHICH WILL DEVELOP WEST TO EAST BEGINNING BY LATE MORNING IN THE WEST. OUTLOOK... MON...MVFR WITH -SHSN WEST...MAINLY VFR CENTRAL AND EASTERN AREAS. TUE...MVFR -SHSN NW. MAINLY VFR ELSEWHERE. WED-THU...MAINLY VFR. && .CTP WATCHES/WARNINGS/ADVISORIES... WINTER WEATHER ADVISORY UNTIL 8 PM EST THIS EVENING FOR PAZ004>006-010-011-017-024-033-042-058. WIND CHILL ADVISORY FROM 11 PM THIS EVENING TO 10 AM EST SUNDAY FOR PAZ004>006-010>012-017-018-024-033-037-041-042. && $$ SYNOPSIS...LA CORTE NEAR TERM...LA CORTE SHORT TERM...LA CORTE LONG TERM...LAMBERT/GARTNER AVIATION...LA CORTE/MARTIN
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
358 PM EST SAT JAN 25 2014 .SYNOPSIS... AN ANOMALOUS UPPER LEVEL TROUGH WILL REMAIN ENTRENCHED OVER THE REGION FOR THE NEXT SEVERAL DAYS...WITH VERY COLD/BELOW NORMAL TEMPERATURES CONTINUING TO IMPACT CENTRAL PENNSYLVANIA THROUGH THE END OF THE MONTH. && .NEAR TERM /UNTIL 6 AM SUNDAY MORNING/... LIGHT SNOW HAS FINALLY BEGUN AT ALTOONA AND STATE COLLEGE AS DOWNSLOPING DOES FINE WORK IN RETARDING THE EASTWARD PROGRESS OF THE SNOW SHIELD ASSOCIATED WITH THE WARM ADVECTION AHEAD OF OUR APPROACHING COLD FRONT. MESO ANAL SHOWS THE COLD FRONT ENTERING NW OHIO AS OF 17Z...WITH A VERY HARD TO FIND WARM FRONT SNAKING UP THRU SERN PA. THIS FEATURE SHOWS UP BEST IN THE LOW LEVEL LI FIELD...BUT TEMP AND WIND CHANGES ACROSS THE BOUNDARY ARE SUBTLE AT BEST. STABILITY IS ERODING AHEAD OF THE FRONT THROUGH OHIO...BUT AS YET THERE ARE NO SIGNS OF THE KIND OF SQUALL LINE THE HIGH RES WRF HAS BEEN ADVERTISING. THE 16Z RAP DOESN`T SHOW A COHERENT LINE ADVANCING THRU CENTRAL PA...JUST SOME SCATTERED SNOW SHOWERS FOR THE MOST PART. THE OTHER NOTEWORTHY ASPECT OF THE WEATHER MOVING OUR WAY WILL BE THE INCREASINGLY GUSTY WIND AND INVADING COLD. UPSTREAM WINDS ARE RUNNING 25-35MPH...COMBINED WITH EXPECTED LOWS IN THE SINGLE DIGITS TO BELOW ZERO OVER THE NORTH...WILL CREATE WIND CHILLS BELOW ZERO IN MOST AREAS BY MORNING. HAVE DECIDED TO REMAIN WITH THE CURRENT ADVISORY CONFIGURATION AS MODELS ARE CONSISTENT IN SHOWING OUR WESTERN ZONES SEEING SEVERAL INCHES OF SNOW...AS WELL A SECONDARY AREA OVER THE HIGHER ELEVATIONS OF THE EAST WHERE SOME UPSLOPE COMBINES WITH THE WARM ADVECTION TO BRING SLIGHTLY HIGHER AMOUNTS. RATIOS WILL BE MORE IMPORTANT THERE SO CONFIDENCE IS LOWER...BUT NOT LOW ENOUGH TO CANCEL THE ADVISORY. THE FRONT SHOULD BE OFFSHORE BY MIDNIGHT..LEAVING A COLDER NW FLOW OVER THE AREA. THIS SHOULD CONFINE THE REMAINDER OF THE SNOW-SHOWER ACTIVITY TO THE UPSLOPE AREAS OF THE WEST AND NORTH...BUT WITH LAKE ERIE BEING ALMOST TOTALLY FROZEN...LAKE EFFECT WILL NOT BE A SIGNIFICANT CONTRIBUTOR TO THE MOISTURE AND PRECIP. && .SHORT TERM /6 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/... ONLY THE BRIEFEST OF RESPITES IS IN STORE FOR THE REGION EARLY SUNDAY AS THE FIRST CLIPPER DEPARTS...AND THE NEXT IN THE WAVE TRAIN APPROACHES. AT THIS POINT TIMING WOULD SUGGEST A DRY MORNING GIVING WAY TO THICKENING CLOUDS AND LIGHT SNOW MOVING INTO AT LEAST MY WESTERN ZONES BY MID TO LATE AFTERNOON. MOISTURE WILL BE TYPICALLY LIMITED WITH THE NEXT WAVE...AND INSTABILITY IS NOT ADVERTISED TO BE ESPECIALLY IMPRESSIVE...SO SNOW AMOUNTS WILL REMAIN LIGHT TO INSIGNIFICANT IN MOST AREAS. && .LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/... THIS ABOVE NOTED CLIPPER WILL BRING ANOTHER WILD TEMPERATURE SWING...FROM SLOWLY RISING TEMPS LATE SUNDAY THROUGH SUNDAY NIGHT /WHICH MAY BRING THE WARMEST READINGS OF THE ENTIRE WEEK TO MANY LOCALES AROUND SUNRISE MONDAY/...FOLLOWED BY A PLUNGE IN THE MERCURY THROUGH THE DAY MONDAY INTO EARLY TUESDAY BEHIND THE TRAILING COLD FROND AS VERY COLD ARCTIC AIR AGAIN GRIPS THE REGION THROUGH MIDWEEK. PERIODS OF MAINLY LIGHT SNOW OR SNOW SHOWERS WILL COINCIDE WITH THE PASSAGE OF THE UPPER LEVEL SHORT WAVE AND SFC CFRONT. 03Z SREF SHOWS QUITE GOOD CLUSTERING OF PLUMES BETWEEN 0.10 AND 0.25 LEQ ACROSS THE NW HALF OF THE CWA LATE SUNDAY THROUGH THE MID MORNING HOURS MONDAY...WHILE LOCATIONS FURTHER TO THE SOUTHEAST HAVE SREF MEAN LIQUID EQUIVALENT QPF OF LESS THAN 0.10. ACCUMS OF A COATING TO 2 INCHES ARE LIKELY...ACROSS CENTRAL PENN. THE POTENTIAL EXISTS FOR ANOTHER/SIMILAR ROUND OF ADVISORY CRITERIA 2-4 INCH SNOW OVER THE NW MTNS AND LAURELS...PRECEDING ANY OROGRAPHIC/LES SNOW SHOWERS/LOCALIZED SQUALLS THAT OCCURS IN THE WAKE OF THE COLD FRONT MONDAY AND MONDAY NIGHT. MEDIUM RANGE OPERATIONAL GUIDANCE AND ENSEMBLES INDICATE THAT WE COULD SEE VERY SIMILAR TEMPS TO WHAT WE EXPERIENCED DURING THE EARLY JANUARY...RECORD COLD OUTBREAK. MODEL GUIDANCE ALMOST UNANIMOUSLY BRINGS LOW TEMPS BELOW ZERO TO ENTIRE CWA TUE AND WED MORNING...WITH -10F OR COLDER IN THE NORTHERN MTNS AND LAUREL HIGHLANDS. TUESDAY WILL BRING THE COLDEST HIGHS OF THE WEEK...AS TEMPS MAY STRUGGLE TO GET ABOVE ZERO ACROSS THE HIGHER ELEVATIONS...AND INCH ONLY INTO THE MID TEENS IN THE SE. THERE/S HIGH CONFIDENCE THAT WE/LL SEE WIDESPREAD WIND CHILL ADVISORY CRITERIA /OF -15F/ BEING MET LATE MONDAY NIGHT THROUGH WEDNESDAY /WITH A SEEMINGLY HIGH POTENTIAL FOR WARNING CRITERIA OF -25F ACROSS HIGHER TERRAIN OF THE NORTH AND WEST MAINLY MON NIGHT INTO TUE WITH BREEZY CONDITIONS. LIGHTER WINDS FOR WED WILL LIKELY PRECLUDE WC WARNINGS...BUT EVEN A LIGHT BREEZE WILL BRING WIND CHILLS BACK BELOW -15 TUE NIGHT INTO WED...WITH COLDER TEMP READINGS POSS AS THE WINDS LIGHTEN AND SKIES POTENTIALLY CLEAR OUT WITH HIGH PRESSURE RIDGING IN FROM THE WEST. ANY SNOW SHOWERS AND LIGHT TO MDT ACCUMS /MONDAY NIGHT INTO WEDNESDAY/ SHOULD BE STRICTLY CONFINED TO THE FAR NW ZONES...AND PERHAPS THE RIDGES OF WRN SOMERSET/CAMBRIA COUNTIES. OTHER THAN THE BITTER COLD /TEMPS ABOUT 20F BELOW NORMAL/ THE MID-LATE WEEK WEATHER WILL BE OVERALL QUIET AS SURFACE HIGH PRESSURE RIDGE SETTLES IN. FLOW TURNS MORE SW HEADING INTO THE WEEKEND...WHICH WILL BRING A GRADUAL WARMING TREND BACK TOWARD ONLY 5-10F BELOW NORMAL. THIS TREND IS LIKELY TO CONTINUE INTO NEXT WEEK AS MODEL AND ENSEMBLE GUIDANCE SUGGESTS THE VERY AMPLIFIED ERN TROUGH PATTERN BEGINS TO RELAX AS THE STRONG WEST COAST RIDGE FINALLY BREAKS DOWN...WHICH SHOULD BRING RELIEF FROM THE BITTER COLD AS WE ENTER INTO FEBRUARY. && .AVIATION /21Z SATURDAY THROUGH THURSDAY/... SNOW OVER WESTERN HIGH TERRAIN TERMINALS WILL KEEP IFR CONDITIONS INTO THE EVENING WHEN GRADUAL IMPROVEMENT WILL DEVELOP AS A COLD FRONT MOVES THROUGH THE AREA AND BRINGS A WIND SHIFT AND COLDER- DRIER AIR FOR THE REMAINDER OF THE OVERNIGHT INTO THE FIRST PART OF SUNDAY. OVER CENTRAL AND EASTERN AREAS...OCNL MVFR/IFR IN THE LIGHT SNOW WITH VISIBILITY BEING THE MAIN ISSUE...AVERAGING 1-3 MILES IN THE LIGHT SNOW. SIMILAR TO WESTERN AREAS...CONDITIONS WILL IMPROVE OVERNIGHT IN THE POST FRONTAL ENVIRONMENT. THE WIND WILL SHIFT AND BE GUSTY OUT OF THE WNW OVERNIGHT...WITH GUSTS OF 25-30KT COMMON...ESPECIALLY OVER THE RIDGES. THIS WILL CREATE ISSUES WITH BLOWING SNOW WHERE ACCUM SNOW HAS OCCURRED TODAY...MAINLY OVER WESTERN AND NORTHERN AREAS. A NEW SYSTEM APPROACHING SUNDAY WILL BRING MORE LIGHT SNOW AND FLIGHT RESTRICTIONS WHICH WILL DEVELOP WEST TO EAST BEGINNING BY LATE MORNING IN THE WEST. OUTLOOK... MON...MVFR WITH -SHSN WEST...MAINLY VFR CENTRAL AND EASTERN AREAS. TUE...MVFR -SHSN NW. MAINLY VFR ELSEWHERE. WED-THU...MAINLY VFR. && .CTP WATCHES/WARNINGS/ADVISORIES... WINTER WEATHER ADVISORY UNTIL 8 PM EST THIS EVENING FOR PAZ004>006-010-011-017-024-033-042-058. WIND CHILL ADVISORY FROM 11 PM THIS EVENING TO 10 AM EST SUNDAY FOR PAZ004>006-010>012-017-018-024-033-037-041-042. && $$ SYNOPSIS...LA CORTE NEAR TERM...LA CORTE SHORT TERM...LA CORTE LONG TERM...LAMBERT/GARTNER AVIATION...LA CORTE
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
142 PM EST SAT JAN 25 2014 .SYNOPSIS... AN ANOMALOUS UPPER LEVEL TROUGH WILL REMAIN ENTRENCHED OVER THE REGION FOR THE NEXT SEVERAL DAYS...WITH VERY COLD/BELOW NORMAL TEMPERATURES CONTINUING TO IMPACT CENTRAL PENNSYLVANIA THROUGH THE END OF THE MONTH. && .NEAR TERM /THROUGH TONIGHT/... LIGHT SNOW HAS FINALLY BEGUN AT ALTOONA AND STATE COLLEGE AS DOWNSLOPING DOES FINE WORK IN RETARDING THE EASTWARD PROGRESS OF THE SNOW SHIELD ASSOCIATED WITH THE WARM ADVECTION AHEAD OF OUR APPROACHING COLD FRONT. MESO ANAL SHOWS THE COLD FRONT ENTERING NW OHIO AS OF 17Z...WITH A VERY HARD TO FIND WARM FRONT SNAKING UP THRU SERN PA. THIS FEATURE SHOWS UP BEST IN THE LOW LEVEL LI FIELD...BUT TEMP AND WIND CHANGES ACROSS THE BOUNDARY ARE SUBTLE AT BEST. STABILITY IS ERODING AHEAD OF THE FRONT THROUGH OHIO...BUT AS YET THERE ARE NO SIGNS OF THE KIND OF SQUALL LINE THE HIGH RES WRF HAS BEEN ADVERTISING. THE 16Z RAP DOESN`T SHOW A COHERENT LINE ADVANCING THRU CENTRAL PA...JUST SOME SCATTERED SNOW SHOWERS FOR THE MOST PART. THE OTHER NOTEWORTHY ASPECT OF THE WEATHER MOVING OUR WAY WILL BE THE INCREASINGLY GUSTY WIND AND INVADING COLD. UPSTREAM WINDS ARE RUNNING 25-35MPH...COMBINED WITH EXPECTED LOWS IN THE SINGLE DIGITS TO BELOW ZERO OVER THE NORTH...WILL CREATE WIND CHILLS BELOW ZERO IN MOST AREAS BY MORNING. HAVE DECIDED TO REMAIN WITH THE CURRENT ADVISORY CONFIGURATION AS MODELS ARE CONSISTENT IN SHOWING OUR WESTERN ZONES SEEING SEVERAL INCHES OF SNOW...AS WELL A SECONDARY AREA OVER THE HIGHER ELEVATIONS OF THE EAST WHERE SOME UPSLOPE COMBINES WITH THE WARM ADVECTION TO BRING SLIGHTLY HIGHER AMOUNTS. RATIOS WILL BE MORE IMPORTANT THERE SO CONFIDENCE IS LOWER...BUT NOT LOW ENOUGH TO CANCEL THE ADVISORY. THE FRONT SHOULD BE OFFSHORE BY MIDNIGHT..LEAVING A COLDER NW FLOW OVER THE AREA. THIS SHOULD CONFINE THE REMAINDER OF THE SNOW-SHOWER ACTIVITY TO THE UPSLOPE AREAS OF THE WEST AND NORTH...BUT WITH LAKE ERIE BEING ALMOST TOTALLY FROZEN...LAKE EFFECT WILL NOT BE A SIGNIFICANT CONTRIBUTOR TO THE MOISTURE AND PRECIP. && .SHORT TERM /SUNDAY/... ONLY THE BRIEFEST OF RESPITES IS IN STORE FOR THE REGION EARLY SUNDAY AS THE FIRST CLIPPER DEPARTS...AND THE NEXT IN THE WAVE TRAIN APPROACHES. AT THIS POINT TIMING WOULD SUGGEST A DRY MORNING GIVING WAY TO THICKENING CLOUDS AND LIGHT SNOW MOVING INTO AT LEAST MY WESTERN ZONES BY MID TO LATE AFTERNOON. MOISTURE WILL BE TYPICALLY LIMITED WITH THE NEXT WAVE...AND INSTABILITY IS NOT ADVERTISED TO BE ESPECIALLY IMPRESSIVE...SO SNOW AMOUNTS WILL REMAIN LIGHT TO INSIGNIFICANT IN MOST AREAS. && .LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/... THIS ABOVE NOTED CLIPPER WILL BRING ANOTHER WILD TEMPERATURE SWING...FROM SLOWLY RISING TEMPS LATE SUNDAY THROUGH SUNDAY NIGHT /WHICH MAY BRING THE WARMEST READINGS OF THE ENTIRE WEEK TO MANY LOCALES AROUND SUNRISE MONDAY/...FOLLOWED BY A PLUNGE IN THE MERCURY THROUGH THE DAY MONDAY INTO EARLY TUESDAY BEHIND THE TRAILING COLD FROND AS VERY COLD ARCTIC AIR AGAIN GRIPS THE REGION THROUGH MIDWEEK. PERIODS OF MAINLY LIGHT SNOW OR SNOW SHOWERS WILL COINCIDE WITH THE PASSAGE OF THE UPPER LEVEL SHORT WAVE AND SFC CFRONT. 03Z SREF SHOWS QUITE GOOD CLUSTERING OF PLUMES BETWEEN 0.10 AND 0.25 LEQ ACROSS THE NW HALF OF THE CWA LATE SUNDAY THROUGH THE MID MORNING HOURS MONDAY...WHILE LOCATIONS FURTHER TO THE SOUTHEAST HAVE SREF MEAN LIQUID EQUIVALENT QPF OF LESS THAN 0.10. ACCUMS OF A COATING TO 2 INCHES ARE LIKELY...ACROSS CENTRAL PENN. THE POTENTIAL EXISTS FOR ANOTHER/SIMILAR ROUND OF ADVISORY CRITERIA 2-4 INCH SNOW OVER THE NW MTNS AND LAURELS...PRECEDING ANY OROGRAPHIC/LES SNOW SHOWERS/LOCALIZED SQUALLS THAT OCCURS IN THE WAKE OF THE COLD FRONT MONDAY AND MONDAY NIGHT. MEDIUM RANGE OPERATIONAL GUIDANCE AND ENSEMBLES INDICATE THAT WE COULD SEE VERY SIMILAR TEMPS TO WHAT WE EXPERIENCED DURING THE EARLY JANUARY...RECORD COLD OUTBREAK. MODEL GUIDANCE ALMOST UNANIMOUSLY BRINGS LOW TEMPS BELOW ZERO TO ENTIRE CWA TUE AND WED MORNING...WITH -10F OR COLDER IN THE NORTHERN MTNS AND LAUREL HIGHLANDS. TUESDAY WILL BRING THE COLDEST HIGHS OF THE WEEK...AS TEMPS MAY STRUGGLE TO GET ABOVE ZERO ACROSS THE HIGHER ELEVATIONS...AND INCH ONLY INTO THE MID TEENS IN THE SE. THERE/S HIGH CONFIDENCE THAT WE/LL SEE WIDESPREAD WIND CHILL ADVISORY CRITERIA /OF -15F/ BEING MET LATE MONDAY NIGHT THROUGH WEDNESDAY /WITH A SEEMINGLY HIGH POTENTIAL FOR WARNING CRITERIA OF -25F ACROSS HIGHER TERRAIN OF THE NORTH AND WEST MAINLY MON NIGHT INTO TUE WITH BREEZY CONDITIONS. LIGHTER WINDS FOR WED WILL LIKELY PRECLUDE WC WARNINGS...BUT EVEN A LIGHT BREEZE WILL BRING WIND CHILLS BACK BELOW -15 TUE NIGHT INTO WED...WITH COLDER TEMP READINGS POSS AS THE WINDS LIGHTEN AND SKIES POTENTIALLY CLEAR OUT WITH HIGH PRESSURE RIDGING IN FROM THE WEST. ANY SNOW SHOWERS AND LIGHT TO MDT ACCUMS /MONDAY NIGHT INTO WEDNESDAY/ SHOULD BE STRICTLY CONFINED TO THE FAR NW ZONES...AND PERHAPS THE RIDGES OF WRN SOMERSET/CAMBRIA COUNTIES. OTHER THAN THE BITTER COLD /TEMPS ABOUT 20F BELOW NORMAL/ THE MID-LATE WEEK WEATHER WILL BE OVERALL QUIET AS SURFACE HIGH PRESSURE RIDGE SETTLES IN. FLOW TURNS MORE SW HEADING INTO THE WEEKEND...WHICH WILL BRING A GRADUAL WARMING TREND BACK TOWARD ONLY 5-10F BELOW NORMAL. THIS TREND IS LIKELY TO CONTINUE INTO NEXT WEEK AS MODEL AND ENSEMBLE GUIDANCE SUGGESTS THE VERY AMPLIFIED ERN TROUGH PATTERN BEGINS TO RELAX AS THE STRONG WEST COAST RIDGE FINALLY BREAKS DOWN...WHICH SHOULD BRING RELIEF FROM THE BITTER COLD AS WE ENTER INTO FEBRUARY. && .AVIATION /18Z SATURDAY THROUGH THURSDAY/... SNOW OVER WESTERN HIGH TERRAIN TERMINALS WILL KEEP IFR CONDITIONS INTO THE EVENING WHEN GRADUAL IMPROVEMENT WILL DEVELOP AS A COLD FRONT MOVES THROUGH THE AREA AND BRINGS A WIND SHIFT AND COLDER- DRIER AIR FOR THE REMAINDER OF THE OVERNIGHT INTO THE FIRST PART OF SUNDAY. OVER CENTRAL AND EASTERN AREAS...OCNL MVFR/IFR IN THE LIGHT SNOW WITH VISIBILITY BEING THE MAIN ISSUE...AVERAGING 1-3 MILES IN THE LIGHT SNOW. SIMILAR TO WESTERN AREAS...CONDITIONS WILL IMPROVE OVERNIGHT IN THE POST FRONTAL ENVIRONMENT. THE WIND WILL SHIFT AND BE GUSTY OUT OF THE WNW OVERNIGHT...WITH GUSTS OF 25-30KT COMMON...ESPECIALLY OVER THE RIDGES. THIS WILL CREATE ISSUES WITH BLOWING SNOW WHERE ACCUM SNOW HAS OCCURRED TODAY...MAINLY OVER WESTERN AND NORTHERN AREAS. A NEW SYSTEM APPROACHING SUNDAY WILL BRING MORE LIGHT SNOW AND FLIGHT RESTRICTIONS WHICH WILL DEVELOP WEST TO EAST BEGINNING BY LATE MORNING IN THE WEST. OUTLOOK... MON...MVFR WITH -SHSN WEST...MAINLY VFR CENTRAL AND EASTERN AREAS. TUE...MVFR -SHSN NW. MAINLY VFR ELSEWHERE. WED-THU...MAINLY VFR. && .CTP WATCHES/WARNINGS/ADVISORIES... WINTER WEATHER ADVISORY UNTIL 8 PM EST THIS EVENING FOR PAZ004>006-010-011-017-024-033-042-058. WIND CHILL ADVISORY FROM 11 PM THIS EVENING TO 10 AM EST SUNDAY FOR PAZ004>006-010>012-017-018-024-033-037-041-042. && $$ SYNOPSIS...LA CORTE NEAR TERM...LA CORTE SHORT TERM...LA CORTE LONG TERM...LAMBERT/RXR AVIATION...LA CORTE
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NWS RAPID CITY SD
919 PM MST FRI JAN 24 2014 .UPDATE... ISSUED AT 704 PM MST FRI JAN 24 2014 00Z KUNR SOUNDING SHOWED WELL MIXED BOUNDARY LAYER TO 750MB WITH 66KTS AT THE TOP OF LAYER. 02Z SURFACE ANALYSIS SHOWED 3MB/3HR PRESSURE RISE BUBBLE HEADING SOUTH ACROSS THE NORTHWEST SD PLAINS. THIS CAUSED PEAK GUST OF THE DAY AT THE OFFICE OVER THE PAST HOUR. LATEST RAP BUFKIT DEPICTIONS MATCH THIS FAIRLY WELL AND KEEP STRONG GUSTY WINDS THROUGH ABOUT 07Z. THUS...HAVE EXTENDED HIGH WIND WARNING FOR THE SQUEEZE ZONE NEAR RAPID CITY THROUGH 07Z AND THE REST OF THE CWA WITH A WIND ADVISORY. && .SHORT TERM...THIS EVENING THROUGH SATURDAY NIGHT ISSUED AT 235 PM MST FRI JAN 24 2014 CURRENT SURFACE MAP SHOWS LOW NEAR WESTERN GREAT LAKES...WITH TIGHT PRESSURE GRADIENT ACROSS THE WESTERN DAKOTAS. ABUNDANT CLOUD COVER AND STRONG LOW LEVEL WAA RESPONSIBLE FOR SLOW START TO STRONG WINDS. WITH SOME BREAKS IN CLOUDS AND TRANSITION TO WEAK COLD ADVECTION...LOCATIONS FROM K2WX-KRAP HAVE BEEN GUSTING OVER 55MPH FOR THE LAST HOUR. WILL LET WIND HEADLINES RUN THROUGH THIS EVENING. WEAK SHORTWAVE CROSSES THE AREA TONIGHT...WITH A FEW RAIN/SNOW SHOWERS POSSIBLE. BEST CHANCE WILL BE OVER THE BLACK HILLS WHERE FROUDE/RH FAVORABLE FOR SOME UPSLOPE ENHANCEMENT. PRECIPITATION SHIFTS EAST SATURDAY MORNING. MILD TEMPERATURES AGAIN ON SATURDAY. WILL BECOME BREEZY ACROSS NORTHWEST SOUTH DAKOTA. && .LONG TERM...SUNDAY THROUGH FRIDAY ISSUED AT 235 PM MST FRI JAN 24 2014 THE REGION WILL REMAIN IN FAST NORTHWEST FLOW ALOFT SUNDAY INTO EARLY NEXT WEEK AS HIGH AMPLITUDE RIDGE PERSISTS ALONG THE PACIFIC COAST. THE NEXT STRONG ARCTIC FRONT IS PROGGED TO CROSS THE CWA SUNDAY...BRINGING SNOW AND QUICKLY FALLING TEMPERATURES BY AFTERNOON. IN ADDITION...VERY WINDY CONDITIONS CAN BE EXPECTED ACROSS THE SD PLAINS SUNDAY INTO SUNDAY EVENING...WITH BLOWING AND DRIFTING SNOW POSSIBLE. A SLOW WARMUP IS EXPECTED EARLY NEXT WEEK...WITH TEMPS RISING BACK TO NEAR AVERAGE LEVELS BY WEDNESDAY. PERSISTENT HUDSON BAY LOW WILL KEEP CYCLONIC FLOW ACROSS THE NORTHERN PLAINS FOR THE LATTER HALF OF NEXT WEEK. BELOW AVERAGE TEMPERATURES AND SMALL CHANCES FOR PRECIPITATION ARE EXPECTED. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 918 PM MST FRI JAN 24 2014 ISOLATED SHOWERS AND VERY GUSTY WEST TO NORTHWEST WINDS WILL CONTINUE THIS EVENING ACROSS THE SD PLAINS...DIMINISHING AFTER MIDNIGHT. CONDITIONS WILL DETERIORATE TO IFR TONIGHT ACROSS THE BLACK HILLS AREA AS UPSLOPE SNOW DEVELOPS...WITH AREAS OF MVFR CEILINGS EXPECTED ACROSS NORTHEAST WYOMING AND THE SD PLAINS. && .UNR WATCHES/WARNINGS/ADVISORIES... SD...WIND ADVISORY UNTIL MIDNIGHT MST /1 AM CST/ TONIGHT FOR SDZ001- 002-012>014-025-030-032-042>044-046-047-049-072. HIGH WIND WARNING UNTIL MIDNIGHT MST TONIGHT FOR SDZ026-031-073. WY...NONE. && $$ UPDATE...HELGESON SHORT TERM...7 LONG TERM...15 AVIATION...HELGESON
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NWS RAPID CITY SD
709 PM MST FRI JAN 24 2014 .UPDATE... ISSUED AT 704 PM MST FRI JAN 24 2014 00Z KUNR SOUNDING SHOWED WELL MIXED BOUNDARY LAYER TO 750MB WITH 66KTS AT THE TOP OF LAYER. 02Z SURFACE ANALYSIS SHOWED 3MB/3HR PRESSURE RISE BUBBLE HEADING SOUTH ACROSS THE NORTHWEST SD PLAINS. THIS CAUSED PEAK GUST OF THE DAY AT THE OFFICE OVER THE PAST HOUR. LATEST RAP BUFKIT DEPICTIONS MATCH THIS FAIRLY WELL AND KEEP STRONG GUSTY WINDS THROUGH ABOUT 07Z. THUS...HAVE EXTENDED HIGH WIND WARNING FOR THE SQUEEZE ZONE NEAR RAPID CITY THROUGH 07Z AND THE REST OF THE CWA WITH A WIND ADVISORY. && .SHORT TERM...THIS EVENING THROUGH SATURDAY NIGHT ISSUED AT 235 PM MST FRI JAN 24 2014 CURRENT SURFACE MAP SHOWS LOW NEAR WESTERN GREAT LAKES...WITH TIGHT PRESSURE GRADIENT ACROSS THE WESTERN DAKOTAS. ABUNDANT CLOUD COVER AND STRONG LOW LEVEL WAA RESPONSIBLE FOR SLOW START TO STRONG WINDS. WITH SOME BREAKS IN CLOUDS AND TRANSITION TO WEAK COLD ADVECTION...LOCATIONS FROM K2WX-KRAP HAVE BEEN GUSTING OVER 55MPH FOR THE LAST HOUR. WILL LET WIND HEADLINES RUN THROUGH THIS EVENING. WEAK SHORTWAVE CROSSES THE AREA TONIGHT...WITH A FEW RAIN/SNOW SHOWERS POSSIBLE. BEST CHANCE WILL BE OVER THE BLACK HILLS WHERE FROUDE/RH FAVORABLE FOR SOME UPSLOPE ENHANCEMENT. PRECIPITATION SHIFTS EAST SATURDAY MORNING. MILD TEMPERATURES AGAIN ON SATURDAY. WILL BECOME BREEZY ACROSS NORTHWEST SOUTH DAKOTA. && .LONG TERM...SUNDAY THROUGH FRIDAY ISSUED AT 235 PM MST FRI JAN 24 2014 THE REGION WILL REMAIN IN FAST NORTHWEST FLOW ALOFT SUNDAY INTO EARLY NEXT WEEK AS HIGH AMPLITUDE RIDGE PERSISTS ALONG THE PACIFIC COAST. THE NEXT STRONG ARCTIC FRONT IS PROGGED TO CROSS THE CWA SUNDAY...BRINGING SNOW AND QUICKLY FALLING TEMPERATURES BY AFTERNOON. IN ADDITION...VERY WINDY CONDITIONS CAN BE EXPECTED ACROSS THE SD PLAINS SUNDAY INTO SUNDAY EVENING...WITH BLOWING AND DRIFTING SNOW POSSIBLE. A SLOW WARMUP IS EXPECTED EARLY NEXT WEEK...WITH TEMPS RISING BACK TO NEAR AVERAGE LEVELS BY WEDNESDAY. PERSISTENT HUDSON BAY LOW WILL KEEP CYCLONIC FLOW ACROSS THE NORTHERN PLAINS FOR THE LATTER HALF OF NEXT WEEK. BELOW AVERAGE TEMPERATURES AND SMALL CHANCES FOR PRECIPITATION ARE EXPECTED. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING) ISSUED AT 235 PM MST FRI JAN 24 2014 ISOLATED SHOWERS AND VERY GUSTY WEST TO NORTHWEST WINDS WILL CONTINUE INTO THE EARLY EVENING ACROSS THE SD PLAINS. WIND GUSTS TO 50 KTS CAN BE EXPECTED ACROSS THE NORTHWEST AND WEST CENTRAL SOUTH DAKOTA PLAINS. CONDITIONS WILL DETERIORATE TO IFR TONIGHT ACROSS THE BLACK HILLS AREA AS UPSLOPE SNOW DEVELOPS...WITH AREAS OF MVFR CEILINGS EXPECTED ACROSS NORTHEAST WYOMING AND THE SD PLAINS. && .UNR WATCHES/WARNINGS/ADVISORIES... SD...WIND ADVISORY UNTIL MIDNIGHT MST /1 AM CST/ TONIGHT FOR SDZ001- 002-012>014-025-030-032-042>044-046-047-049-072. HIGH WIND WARNING UNTIL MIDNIGHT MST TONIGHT FOR SDZ026-031-073. WY...NONE. && $$ UPDATE...HELGESON SHORT TERM...7 LONG TERM...15 AVIATION...15
AREA FORECAST DISCUSSION...UPDATED
NWS NASHVILLE TN
1159 AM CST FRI JAN 24 2014 .UPDATE...18Z AVIATION DISCUSSION. && .AVIATION...18Z AVIATION DISCUSSION. UNCERTAINTIES...ACTUAL CEILING PROGRESSION DEVELOPMENTAL TIMING AFTER 25/03Z...IMPACTS OF LIGHT SNOW SHWRS CSV AND LLWS POTENTIAL 25/09Z-25/18Z. AS NEXT CLIPPER SYSTEM APPROACHES MID STATE BY 25/03Z...EXPECT BKN CI CEILINGS TO TRANSITION TO STRATUS VFR CEILINGS BY 25/09Z. ENOUGH MOISTURE MAY BE PRESENT FOR LIGHT SNOW SHWRS CSV FROM 25/12Z-25/18Z...BUT AM INITIALLY EXPECTING VSBY RESTRICTIONS AND ICING POTENTIAL MINIMAL. TIGHTENING SFC PRESSURE GRADIENT SHOULD SUPPORT SFC GUSTS 20-25KTS 25/09Z-25/18Z. JUST ABOVE SFC...MODELS ARE SHOWING CONTINUANCE OF TIGHT PRESSURE GRADIENT WITH POTENTIAL LLWS TO 60KTS 25/10Z-25/18Z. && .PREV DISCUSSION... /ISSUED 520 AM CST FRI JAN 24 2014/ AVIATION UPDATE...FOR 12Z TAF PACKAGE... LOTS OF DRY AIR IN PLACE WITH HIGH PRESSURE OVER THE MID STATE. NOT EXPECTING MUCH IN THE WAY OF CLOUD COVER OVER THE FIRST 18 HOURS OF THE TAF PERIOD. WILL SEE SOME HIGH CEILINGS IMPACT KCKV TOWARDS THE END OF THE PERIOD. WINDS WILL BE ONLY CONCERN THIS TAF PERIOD AS THEY SHIFT SOUTHWEST AND BECOME BREEZY BY THE AFTERNOON HOURS...ESPECIALLY AT KCKV. THESE BREEZY CONDITIONS WILL PERSIST THROUGH THE END OF THE PERIOD. PREV DISCUSSION... /ISSUED 224 AM CST FRI JAN 24 2014/ DISCUSSION... WILL LET THE WIND CHILL ADVISORY EXPIRE AT 12Z. SURFACE HIGH SPRAWLED ACROSS THE REGION THIS MORNING WILL KEEP HIGH TEMPS TODAY ABOUT 20 DEGREES COLDER THAN NORMAL. THIS FOLLOWING THIS MORNINGS LOWS IN THE SINGLE DIGITS. AS SURFACE HIGH SINKS FARTHER SOUTH OF TENNESSEE DURING THE DAY ANOTHER CLIPPER SYSTEM WILL BEGIN ITS DIVE FROM THE HIGH PLAINS WITH A TIGHTENING SURFACE PRESSURE GRADIENT. THIS WILL INCREASE WINDS SPEEDS DURING THE AFTERNOON ON THE ORDER OF 10 TO 20 MPH...ESPECIALLY WESTERN AREAS. ALREADY BEGINNING TO SEE SOME WARM ADVECTION AROUND 850 MBARS ACROSS MISSOURI AND ILLINOIS WITH WINDS JUST NOW BEGINNING TO TURN WESTERLY ACROSS THAT AREA. LATEST RUC SOUNDING SHOWING VERY DRY AIR MASS IN PLACE. I/R SATELLITE LOOP SHOWS CIRRUS FIBRATUS SCOOTING ACROSS NORTHERN MISSISSIPPI/ALABAMA ASSOCIATED WITH 160 KNOTS UPPER LEVEL JET. WITH HIGH TEMPS TODAY IN THE MIDDLE 20S AND A GOOD SOUTHERLY FETCH DEVELOPING AM EXPECTING TEMPS TONIGHT TO ACTUALLY RISE DURING THE EVENING AND OVERNIGHT WITH HIGHS ON SATURDAY CLIMBING INTO THE UPPER 30S AND LOWER 40S. CLIPPER SYSTEM WILL MAKE ITS PRESENTS KNOWN HERE IN THE MID STATE AS EARLY AS MIDNIGHT TONIGHT WITH LIGHT SNOW ACROSS THE NORTHERN AREAS GENERALLY ALONG AND NORTH OF INTERSTATE 40...CONTINUING EAST OF INTERSTATE 24 SATURDAY MORNING. COULD SEE A HALF INCH ACCUMULATION NORTHEAST MIDDLE TENNESSEE AND UPPER CUMBERLAND SATURDAY MORNING. FRONTAL SYSTEM WILL RACE THROUGH EARLY SATURDAY AFTERNOON FOLLOWED BY COLDER TEMPS SATURDAY NIGHT BUT ITS NOT AS COLD BEHIND THIS CLIPPER AS PREVIOUS CLIPPERS. SURFACE HIGH QUICKLY BUILDS OVER THE AREA SATURDAY NIGHT AND SUNDAY WITH HIGHS ON SUNDAY AROUND 50 MANY AREAS WITH MIDDLE 40S ALONG THE PLATEAU. A STRONGER CLIPPER COMES THROUGH SUNDAY NIGHT KNOCKING TEMPS DOWN ONCE AGAIN. THE WORK WEEK LOOKS COLD AND SOMEWHAT A REPEAT OF WHAT WE JUST HAD. LOOKING FARTHER OUT THE MODELS ARE SHOWING A PATTERN CHANGE WHERE THE SOUTHERN BRANCH OF THE POLAR JET BECOMES DOMINATE. THIS BEGINS TO SHOW UP ON THE EURO BY THE 31ST OF JANUARY AND CONTINUES PAST GROUNDHOG DAY. LETS HOPE ITS A CLOUDY DAY WHEN HE EMERGES FROM HIS BURROW. && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 31
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
520 AM CST FRI JAN 24 2014 .AVIATION UPDATE...FOR 12Z TAF PACKAGE... LOTS OF DRY AIR IN PLACE WITH HIGH PRESSURE OVER THE MID STATE. NOT EXPECTING MUCH IN THE WAY OF CLOUD COVER OVER THE FIRST 18 HOURS OF THE TAF PERIOD. WILL SEE SOME HIGH CEILINGS IMPACT KCKV TOWARDS THE END OF THE PERIOD. WINDS WILL BE ONLY CONCERN THIS TAF PERIOD AS THEY SHIFT SOUTHWEST AND BECOME BREEZY BY THE AFTERNOON HOURS...ESPECIALLY AT KCKV. THESE BREEZY CONDITIONS WILL PERSIST THROUGH THE END OF THE PERIOD. && .PREV DISCUSSION... /ISSUED 224 AM CST FRI JAN 24 2014/ DISCUSSION... WILL LET THE WIND CHILL ADVISORY EXPIRE AT 12Z. SURFACE HIGH SPRAWLED ACROSS THE REGION THIS MORNING WILL KEEP HIGH TEMPS TODAY ABOUT 20 DEGREES COLDER THAN NORMAL. THIS FOLLOWING THIS MORNINGS LOWS IN THE SINGLE DIGITS. AS SURFACE HIGH SINKS FARTHER SOUTH OF TENNESSEE DURING THE DAY ANOTHER CLIPPER SYSTEM WILL BEGIN ITS DIVE FROM THE HIGH PLAINS WITH A TIGHTENING SURFACE PRESSURE GRADIENT. THIS WILL INCREASE WINDS SPEEDS DURING THE AFTERNOON ON THE ORDER OF 10 TO 20 MPH...ESPECIALLY WESTERN AREAS. ALREADY BEGINNING TO SEE SOME WARM ADVECTION AROUND 850 MBARS ACROSS MISSOURI AND ILLINOIS WITH WINDS JUST NOW BEGINNING TO TURN WESTERLY ACROSS THAT AREA. LATEST RUC SOUNDING SHOWING VERY DRY AIR MASS IN PLACE. I/R SATELLITE LOOP SHOWS CIRRUS FIBRATUS SCOOTING ACROSS NORTHERN MISSISSIPPI/ALABAMA ASSOCIATED WITH 160 KNOTS UPPER LEVEL JET. WITH HIGH TEMPS TODAY IN THE MIDDLE 20S AND A GOOD SOUTHERLY FETCH DEVELOPING AM EXPECTING TEMPS TONIGHT TO ACTUALLY RISE DURING THE EVENING AND OVERNIGHT WITH HIGHS ON SATURDAY CLIMBING INTO THE UPPER 30S AND LOWER 40S. CLIPPER SYSTEM WILL MAKE ITS PRESENTS KNOWN HERE IN THE MID STATE AS EARLY AS MIDNIGHT TONIGHT WITH LIGHT SNOW ACROSS THE NORTHERN AREAS GENERALLY ALONG AND NORTH OF INTERSTATE 40...CONTINUING EAST OF INTERSTATE 24 SATURDAY MORNING. COULD SEE A HALF INCH ACCUMULATION NORTHEAST MIDDLE TENNESSEE AND UPPER CUMBERLAND SATURDAY MORNING. FRONTAL SYSTEM WILL RACE THROUGH EARLY SATURDAY AFTERNOON FOLLOWED BY COLDER TEMPS SATURDAY NIGHT BUT ITS NOT AS COLD BEHIND THIS CLIPPER AS PREVIOUS CLIPPERS. SURFACE HIGH QUICKLY BUILDS OVER THE AREA SATURDAY NIGHT AND SUNDAY WITH HIGHS ON SUNDAY AROUND 50 MANY AREAS WITH MIDDLE 40S ALONG THE PLATEAU. A STRONGER CLIPPER COMES THROUGH SUNDAY NIGHT KNOCKING TEMPS DOWN ONCE AGAIN. THE WORK WEEK LOOKS COLD AND SOMEWHAT A REPEAT OF WHAT WE JUST HAD. LOOKING FARTHER OUT THE MODELS ARE SHOWING A PATTERN CHANGE WHERE THE SOUTHERN BRANCH OF THE POLAR JET BECOMES DOMINATE. THIS BEGINS TO SHOW UP ON THE EURO BY THE 31ST OF JANUARY AND CONTINUES PAST GROUNDHOG DAY. LETS HOPE ITS A CLOUDY DAY WHEN HE EMERGES FROM HIS BURROW. && .OHX WATCHES/WARNINGS/ADVISORIES... WIND CHILL ADVISORY UNTIL 6 AM CST EARLY THIS MORNING FOR TNZ011- 032>034-065-066-078>080. && $$ TB12
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
224 AM CST FRI JAN 24 2014 .DISCUSSION... WILL LET THE WIND CHILL ADVISORY EXPIRE AT 12Z. SURFACE HIGH SPRAWLED ACROSS THE REGION THIS MORNING WILL KEEP HIGH TEMPS TODAY ABOUT 20 DEGREES COLDER THAN NORMAL. THIS FOLLOWING THIS MORNINGS LOWS IN THE SINGLE DIGITS. AS SURFACE HIGH SINKS FARTHER SOUTH OF TENNESSEE DURING THE DAY ANOTHER CLIPPER SYSTEM WILL BEGIN ITS DIVE FROM THE HIGH PLAINS WITH A TIGHTENING SURFACE PRESSURE GRADIENT. THIS WILL INCREASE WINDS SPEEDS DURING THE AFTERNOON ON THE ORDER OF 10 TO 20 MPH...ESPECIALLY WESTERN AREAS. ALREADY BEGINNING TO SEE SOME WARM ADVECTION AROUND 850 MBARS ACROSS MISSOURI AND ILLINOIS WITH WINDS JUST NOW BEGINNING TO TURN WESTERLY ACROSS THAT AREA. LATEST RUC SOUNDING SHOWING VERY DRY AIR MASS IN PLACE. I/R SATELLITE LOOP SHOWS CIRRUS FIBRATUS SCOOTING ACROSS NORTHERN MISSISSIPPI/ALABAMA ASSOCIATED WITH 160 KNOTS UPPER LEVEL JET. WITH HIGH TEMPS TODAY IN THE MIDDLE 20S AND A GOOD SOUTHERLY FETCH DEVELOPING AM EXPECTING TEMPS TONIGHT TO ACTUALLY RISE DURING THE EVENING AND OVERNIGHT WITH HIGHS ON SATURDAY CLIMBING INTO THE UPPER 30S AND LOWER 40S. CLIPPER SYSTEM WILL MAKE ITS PRESENTS KNOWN HERE IN THE MID STATE AS EARLY AS MIDNIGHT TONIGHT WITH LIGHT SNOW ACROSS THE NORTHERN AREAS GENERALLY ALONG AND NORTH OF INTERSTATE 40...CONTINUING EAST OF INTERSTATE 24 SATURDAY MORNING. COULD SEE A HALF INCH ACCUMULATION NORTHEAST MIDDLE TENNESSEE AND UPPER CUMBERLAND SATURDAY MORNING. FRONTAL SYSTEM WILL RACE THROUGH EARLY SATURDAY AFTERNOON FOLLOWED BY COLDER TEMPS SATURDAY NIGHT BUT ITS NOT AS COLD BEHIND THIS CLIPPER AS PREVIOUS CLIPPERS. SURFACE HIGH QUICKLY BUILDS OVER THE AREA SATURDAY NIGHT AND SUNDAY WITH HIGHS ON SUNDAY AROUND 50 MANY AREAS WITH MIDDLE 40S ALONG THE PLATEAU. A STRONGER CLIPPER COMES THROUGH SUNDAY NIGHT KNOCKING TEMPS DOWN ONCE AGAIN. THE WORK WEEK LOOKS COLD AND SOMEWHAT A REPEAT OF WHAT WE JUST HAD. LOOKING FARTHER OUT THE MODELS ARE SHOWING A PATTERN CHANGE WHERE THE SOUTHERN BRANCH OF THE POLAR JET BECOMES DOMINATE. THIS BEGINS TO SHOW UP ON THE EURO BY THE 31ST OF JANUARY AND CONTINUES PAST GROUNDHOG DAY. LETS HOPE ITS A CLOUDY DAY WHEN HE EMERGES FROM HIS BURROW. && .PRELIMINARY POINT TEMPS/POPS... NASHVILLE 26 22 42 22 / 0 20 10 05 CLARKSVILLE 26 23 38 20 / 0 30 10 05 CROSSVILLE 23 20 34 19 / 0 10 30 05 COLUMBIA 27 22 42 22 / 0 10 10 05 LAWRENCEBURG 29 23 43 23 / 0 05 10 05 WAVERLY 26 23 40 21 / 0 20 10 05 && .OHX WATCHES/WARNINGS/ADVISORIES... WIND CHILL ADVISORY UNTIL 6 AM CST EARLY THIS MORNING FOR TNZ011- 032>034-065-066-078>080. && $$ BOYD 01
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
739 AM CST FRI JAN 24 2014 .UPDATE... DROPPING WIND ADVISORY FOR THE COAST. && .DISCUSSION... GRADIENT HAS WEAKENED SO WILL DROP THE ADVISORY FOR THE COASTAL COUNTIES. WILL LET THE WSW CONTINUE DEPITE THE DWINDLING THREAT FOR ADDITIONAL PRECIP. ROADS ARE ICY EVERYWHERE AND FEEL IT IS BEST JUST TO KEEP THE WARNING GOING. 43 && .PREV DISCUSSION... /ISSUED 545 AM CST FRI JAN 24 2014/ DISCUSSION... SEE THE 12Z AVIATION DISCUSSION BELOW. MARINE DISCUSSION INCLUDED AS WELL. 40 AVIATION... RADAR TRENDS WERE ENDING THE PRECIP OVER KCLL AND KUTS. THINK THAT THESE LOCATIONS MAY SEE SOME FREEZING DRIZZLE OR ICE PELLETS THROUGH 13Z. TRENDED THE ENDING OF THE PRECIP AT KCXO AND KIAH. WAS LESS CONFIDENT ABOUT THE ENDING OF THE PRECIP FROM KHOU AND KSGR TO THE COAST. RADAR INDICATED ISENTROPIC LIFT WAS CONTINUING TO GENERATE PRECIP WELL WEST OF KLBX. TEMPERATURES SHOULD BE NEAR FREEZING THROUGH ABOUT 15Z BEFORE SLOWLY WARMING ABOVE FREEZING DURING THE LATE MORNING. THE MODELS KEEP A CHANCE OF RAIN AT THESE TWO SITES INTO THE EARLY AFTERNOON. VFR SHOULD DEVELOP LATE THIS AFTERNOON IN THE NORTH AND EARLY THIS EVENING TOWARD THE COAST. 40 MARINE... GALE FORCE WINDS WILL DIMINISH THIS MORNING AS THE SURFACE PRESSURE GRADIENT RELAXES. HOWEVER...STRONG COLD AIR ADVECTION WILL CONTINUE TO PROVIDE FOR STRONG WINDS THROUGH AT LEAST MIDDAY OVER THE NEARSHORE WATERS. HIGH PRESSURE WILL MOVE OVERHEAD TONIGHT. ANOTHER STRONG COLD FRONT IS EXPECTED TO MOVE OFF THE COAST ON MONDAY WITH AT LEAST SMALL CRAFT ADVISORIES EXPECTED FOLLOWING THE FRONT. 40 PREV DISCUSSION... /ISSUED 351 AM CST FRI JAN 24 2014/ DISCUSSION... SNOW AND SLEET CONTINUES TO FALL OVER THE NORTHERN HALF OF SOUTHEAST TEXAS. SOME 1 TO 2 INCH TOTALS LOOK LIKELY FROM MADISONVILLE TO HUNTSVILLE TO COLDSPRING. QUITE A LULL IN PRECIP OVER THE SOUTHERN HALF OF THE REGION. COLDER AIR HAS SURGED INTO THE REGION AND RESIDUAL WATER ON ROADWAYS AND BRIDGES WILL START TO FREEZE. TXDOT IS REPORTING ICE ON MANY ROADS TO THE NORTH AND NORTHWEST OF HOUSTON. THE LATEST RAP AND HRRR SHOW PRECIP ENDING QUICKLY FROM WEST TO EAST THIS MORNING AND THIS APPEARS TO BE BACKED UP BY RADAR WHICH SHOWS VERY LITTLE DEVELOPMENT TO THE WEST. THE SOUTHERN HALF OF THE REGION WILL PROBABLY NOT MEET WINTER STORM WARNING CRITERIA BUT DON`T SEE THE SENSE IN SWITCHING THE WARNING TO AN ADVISORY AT THIS POINT. WILL RE-EVALUATE AT 12Z ONCE THE MORNING SOUNDINGS COME IN...BUT FEEL THE WSW COULD BE DROPPED BY 15Z. DON`T BE SURPRISED IF AN UPDATED FORECAST IS ISSUED BETWEEN 6-7 AM. FCST SOUNDINGS SHOW DRYING FROM THE TOP SO SNOW NORTH OF HOUSTON WILL LOSE THEIR ICE CRYSTALS AND PROBABLY TRANSITION BACK TO ICE PELLETS OR FREEZING RAIN. FURTHER SOUTH...06Z SOUNDING LAUNCHED AT THE UNIV OF HOUSTON SHOWS A DEEP SATURATED LAYER WITH A WARM NOSE BETWEEN 900-700 MB AND A SUB-FREEZING LAYER FROM 900 MB TO NEAR 1000 MB. FREEZING RAIN/SLEET MIXTURE WILL AFFECT HOUSTON METRO AREAS FOR THE NEXT 3-4 HOURS BEFORE ENDING. THE STRONG RRQ WHICH HAS ENHANCED LIFT IS PULLING AWAY AND OMEGA WEAKENS RATHER QUICKLY THIS MORNING SO FEEL MOST OF THE SIGNIFICANT PRECIP WILL END EARLY THIS MORNING. FCST SOUNDINGS KEEP THINGS CLOUDY ALL DAY SO DON`T EXPECT TEMPS TO WARM MUCH. SKIES SHOULD CLEAR BY 06Z TONIGHT AND WINDS WILL RELAX LATER TODAY. EXTENDED THE WIND ADVISORY ALONG THE COAST THRU 15Z BUT THE TREND IS FOR WINDS TO RELAX THIS MORNING. WARMER TEMPS ARE EXPECTED SAT/SUN AND MAX TEMPS SHOULD EXCEED 60 DEGREES BOTH DAYS. ANOTHER ARCTIC FRONT WILL CROSS THE AREA ON MONDAY. OVERNIGHT LOWS WILL BE BACK IN THE 20S TUES/WED MORNING WITH MAYBE A FEW SPOTS FALLING INTO THE TEENS. BOTH THE ECMWF/GFS ARE DRY WITH THE NEXT FRONT WHILE THE CANADIAN BRINGS SOME PRECIP ACROSS THE AREA. WILL LEAN TOWARD THE DRIER SOLUTIONS FOR NOW. A WEAK DISTURBANCE COULD BRING SOME RAIN BACK TO THE AREA TOWARD THE END OF NEXT WEEK. && .PRELIMINARY POINT TEMPS/POPS... COLLEGE STATION (CLL) 37 29 59 40 67 / 10 10 10 10 10 HOUSTON (IAH) 36 31 59 42 67 / 20 10 10 10 10 GALVESTON (GLS) 37 37 55 48 64 / 40 10 10 10 10 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...WINTER STORM WARNING UNTIL NOON CST TODAY FOR THE FOLLOWING ZONES: AUSTIN...BRAZORIA...BRAZOS...BURLESON...CHAMBERS... COLORADO...FORT BEND...GALVESTON...GRIMES...HARRIS... HOUSTON...JACKSON...LIBERTY...MADISON...MATAGORDA... MONTGOMERY...POLK...SAN JACINTO...TRINITY...WALKER... WALLER...WASHINGTON...WHARTON. WIND ADVISORY UNTIL 9 AM CST THIS MORNING FOR THE FOLLOWING ZONES: BRAZORIA...CHAMBERS...GALVESTON...JACKSON... MATAGORDA. GM...SMALL CRAFT ADVISORY UNTIL 9 AM CST THIS MORNING FOR THE FOLLOWING ZONES: GALVESTON BAY...MATAGORDA BAY. SMALL CRAFT ADVISORY UNTIL NOON CST TODAY FOR THE FOLLOWING ZONES: WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS FROM HIGH ISLAND TO FREEPORT OUT 20 NM. SMALL CRAFT ADVISORY UNTIL 5 PM CST THIS AFTERNOON FOR THE FOLLOWING ZONES: WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL 20 NM TO 60 NM...WATERS FROM HIGH ISLAND TO FREEPORT 20 TO 60 NM. && $$ DISCUSSION...43
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
545 AM CST FRI JAN 24 2014 .DISCUSSION... SEE THE 12Z AVIATION DISCUSSION BELOW. MARINE DISCUSSION INCLUDED AS WELL. 40 && .AVIATION... RADAR TRENDS WERE ENDING THE PRECIP OVER KCLL AND KUTS. THINK THAT THESE LOCATIONS MAY SEE SOME FREEZING DRIZZLE OR ICE PELLETS THROUGH 13Z. TRENDED THE ENDING OF THE PRECIP AT KCXO AND KIAH. WAS LESS CONFIDENT ABOUT THE ENDING OF THE PRECIP FROM KHOU AND KSGR TO THE COAST. RADAR INDICATED ISENTROPIC LIFT WAS CONTINUING TO GENERATE PRECIP WELL WEST OF KLBX. TEMPERATURES SHOULD BE NEAR FREEZING THROUGH ABOUT 15Z BEFORE SLOWLY WARMING ABOVE FREEZING DURING THE LATE MORNING. THE MODELS KEEP A CHANCE OF RAIN AT THESE TWO SITES INTO THE EARLY AFTERNOON. VFR SHOULD DEVELOP LATE THIS AFTERNOON IN THE NORTH AND EARLY THIS EVENING TOWARD THE COAST. 40 && .MARINE... GALE FORCE WINDS WILL DIMINISH THIS MORNING AS THE SURFACE PRESSURE GRADIENT RELAXES. HOWEVER...STRONG COLD AIR ADVECTION WILL CONTINUE TO PROVIDE FOR STRONG WINDS THROUGH AT LEAST MIDDAY OVER THE NEARSHORE WATERS. HIGH PRESSURE WILL MOVE OVERHEAD TONIGHT. ANOTHER STRONG COLD FRONT IS EXPECTED TO MOVE OFF THE COAST ON MONDAY WITH AT LEAST SMALL CRAFT ADVISORIES EXPECTED FOLLOWING THE FRONT. 40 && .PREV DISCUSSION... /ISSUED 351 AM CST FRI JAN 24 2014/ DISCUSSION... SNOW AND SLEET CONTINUES TO FALL OVER THE NORTHERN HALF OF SOUTHEAST TEXAS. SOME 1 TO 2 INCH TOTALS LOOK LIKELY FROM MADISONVILLE TO HUNTSVILLE TO COLDSPRING. QUITE A LULL IN PRECIP OVER THE SOUTHERN HALF OF THE REGION. COLDER AIR HAS SURGED INTO THE REGION AND RESIDUAL WATER ON ROADWAYS AND BRIDGES WILL START TO FREEZE. TXDOT IS REPORTING ICE ON MANY ROADS TO THE NORTH AND NORTHWEST OF HOUSTON. THE LATEST RAP AND HRRR SHOW PRECIP ENDING QUICKLY FROM WEST TO EAST THIS MORNING AND THIS APPEARS TO BE BACKED UP BY RADAR WHICH SHOWS VERY LITTLE DEVELOPMENT TO THE WEST. THE SOUTHERN HALF OF THE REGION WILL PROBABLY NOT MEET WINTER STORM WARNING CRITERIA BUT DON`T SEE THE SENSE IN SWITCHING THE WARNING TO AN ADVISORY AT THIS POINT. WILL RE-EVALUATE AT 12Z ONCE THE MORNING SOUNDINGS COME IN...BUT FEEL THE WSW COULD BE DROPPED BY 15Z. DON`T BE SURPRISED IF AN UPDATED FORECAST IS ISSUED BETWEEN 6-7 AM. FCST SOUNDINGS SHOW DRYING FROM THE TOP SO SNOW NORTH OF HOUSTON WILL LOSE THEIR ICE CRYSTALS AND PROBABLY TRANSITION BACK TO ICE PELLETS OR FREEZING RAIN. FURTHER SOUTH...06Z SOUNDING LAUNCHED AT THE UNIV OF HOUSTON SHOWS A DEEP SATURATED LAYER WITH A WARM NOSE BETWEEN 900-700 MB AND A SUB-FREEZING LAYER FROM 900 MB TO NEAR 1000 MB. FREEZING RAIN/SLEET MIXTURE WILL AFFECT HOUSTON METRO AREAS FOR THE NEXT 3-4 HOURS BEFORE ENDING. THE STRONG RRQ WHICH HAS ENHANCED LIFT IS PULLING AWAY AND OMEGA WEAKENS RATHER QUICKLY THIS MORNING SO FEEL MOST OF THE SIGNIFICANT PRECIP WILL END EARLY THIS MORNING. FCST SOUNDINGS KEEP THINGS CLOUDY ALL DAY SO DON`T EXPECT TEMPS TO WARM MUCH. SKIES SHOULD CLEAR BY 06Z TONIGHT AND WINDS WILL RELAX LATER TODAY. EXTENDED THE WIND ADVISORY ALONG THE COAST THRU 15Z BUT THE TREND IS FOR WINDS TO RELAX THIS MORNING. WARMER TEMPS ARE EXPECTED SAT/SUN AND MAX TEMPS SHOULD EXCEED 60 DEGREES BOTH DAYS. ANOTHER ARCTIC FRONT WILL CROSS THE AREA ON MONDAY. OVERNIGHT LOWS WILL BE BACK IN THE 20S TUES/WED MORNING WITH MAYBE A FEW SPOTS FALLING INTO THE TEENS. BOTH THE ECMWF/GFS ARE DRY WITH THE NEXT FRONT WHILE THE CANADIAN BRINGS SOME PRECIP ACROSS THE AREA. WILL LEAN TOWARD THE DRIER SOLUTIONS FOR NOW. A WEAK DISTURBANCE COULD BRING SOME RAIN BACK TO THE AREA TOWARD THE END OF NEXT WEEK. && .PRELIMINARY POINT TEMPS/POPS... COLLEGE STATION (CLL) 37 29 59 40 67 / 40 10 10 10 10 HOUSTON (IAH) 36 31 59 42 67 / 70 10 10 10 10 GALVESTON (GLS) 37 37 55 48 64 / 70 10 10 10 10 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...WINTER STORM WARNING UNTIL NOON CST TODAY FOR THE FOLLOWING ZONES: AUSTIN...BRAZORIA...BRAZOS...BURLESON...CHAMBERS... COLORADO...FORT BEND...GALVESTON...GRIMES...HARRIS... HOUSTON...JACKSON...LIBERTY...MADISON...MATAGORDA... MONTGOMERY...POLK...SAN JACINTO...TRINITY...WALKER... WALLER...WASHINGTON...WHARTON. WIND ADVISORY UNTIL 9 AM CST THIS MORNING FOR THE FOLLOWING ZONES: BRAZORIA...CHAMBERS...GALVESTON...JACKSON... MATAGORDA. WIND ADVISORY UNTIL 6 AM CST EARLY THIS MORNING FOR THE FOLLOWING ZONES: FORT BEND...HARRIS...WHARTON. GM...SMALL CRAFT ADVISORY UNTIL 9 AM CST THIS MORNING FOR THE FOLLOWING ZONES: GALVESTON BAY...MATAGORDA BAY. SMALL CRAFT ADVISORY UNTIL NOON CST TODAY FOR THE FOLLOWING ZONES: WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS FROM HIGH ISLAND TO FREEPORT OUT 20 NM. GALE WARNING UNTIL 7 AM CST THIS MORNING FOR THE FOLLOWING ZONES: WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL 20 NM TO 60 NM...WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS FROM HIGH ISLAND TO FREEPORT 20 TO 60 NM...WATERS FROM HIGH ISLAND TO FREEPORT OUT 20 NM. SMALL CRAFT ADVISORY UNTIL 5 PM CST THIS AFTERNOON FOR THE FOLLOWING ZONES: WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL 20 NM TO 60 NM...WATERS FROM HIGH ISLAND TO FREEPORT 20 TO 60 NM. && $$ DISCUSSION...43 AVIATION/MARINE...40
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
351 AM CST FRI JAN 24 2014 .DISCUSSION... SNOW AND SLEET CONTINUES TO FALL OVER THE NORTHERN HALF OF SOUTHEAST TEXAS. SOME 1 TO 2 INCH TOTALS LOOK LIKELY FROM MADISONVILLE TO HUNTSVILLE TO COLDSPRING. QUITE A LULL IN PRECIP OVER THE SOUTHERN HALF OF THE REGION. COLDER AIR HAS SURGED INTO THE REGION AND RESIDUAL WATER ON ROADWAYS AND BRIDGES WILL START TO FREEZE. TXDOT IS REPORTING ICE ON MANY ROADS TO THE NORTH AND NORTHWEST OF HOUSTON. THE LATEST RAP AND HRRR SHOW PRECIP ENDING QUICKLY FROM WEST TO EAST THIS MORNING AND THIS APPEARS TO BE BACKED UP BY RADAR WHICH SHOWS VERY LITTLE DEVELOPMENT TO THE WEST. THE SOUTHERN HALF OF THE REGION WILL PROBABLY NOT MEET WINTER STORM WARNING CRITERIA BUT DON`T SEE THE SENSE IN SWITCHING THE WARNING TO AN ADVISORY AT THIS POINT. WILL RE-EVALUATE AT 12Z ONCE THE MORNING SOUNDINGS COME IN...BUT FEEL THE WSW COULD BE DROPPED BY 15Z. DON`T BE SURPRISED IF AN UPDATED FORECAST IS ISSUED BETWEEN 6-7 AM. FCST SOUNDINGS SHOW DRYING FROM THE TOP SO SNOW NORTH OF HOUSTON WILL LOSE THEIR ICE CRYSTALS AND PROBABLY TRANSITION BACK TO ICE PELLETS OR FREEZING RAIN. FURTHER SOUTH...06Z SOUNDING LAUNCHED AT THE UNIV OF HOUSTON SHOWS A DEEP SATURATED LAYER WITH A WARM NOSE BETWEEN 900-700 MB AND A SUB-FREEZING LAYER FROM 900 MB TO NEAR 1000 MB. FREEZING RAIN/SLEET MIXTURE WILL AFFECT HOUSTON METRO AREAS FOR THE NEXT 3-4 HOURS BEFORE ENDING. THE STRONG RRQ WHICH HAS ENHANCED LIFT IS PULLING AWAY AND OMEGA WEAKENS RATHER QUICKLY THIS MORNING SO FEEL MOST OF THE SIGNIFICANT PRECIP WILL END EARLY THIS MORNING. FCST SOUNDINGS KEEP THINGS CLOUDY ALL DAY SO DON`T EXPECT TEMPS TO WARM MUCH. SKIES SHOULD CLEAR BY 06Z TONIGHT AND WINDS WILL RELAX LATER TODAY. EXTENDED THE WIND ADVISORY ALONG THE COAST THRU 15Z BUT THE TREND IS FOR WINDS TO RELAX THIS MORNING. WARMER TEMPS ARE EXPECTED SAT/SUN AND MAX TEMPS SHOULD EXCEED 60 DEGREES BOTH DAYS. ANOTHER ARCTIC FRONT WILL CROSS THE AREA ON MONDAY. OVERNIGHT LOWS WILL BE BACK IN THE 20S TUES/WED MORNING WITH MAYBE A FEW SPOTS FALLING INTO THE TEENS. BOTH THE ECMWF/GFS ARE DRY WITH THE NEXT FRONT WHILE THE CANADIAN BRINGS SOME PRECIP ACROSS THE AREA. WILL LEAN TOWARD THE DRIER SOLUTIONS FOR NOW. A WEAK DISTURBANCE COULD BRING SOME RAIN BACK TO THE AREA TOWARD THE END OF NEXT WEEK. && .PRELIMINARY POINT TEMPS/POPS... COLLEGE STATION (CLL) 37 29 59 40 67 / 40 10 10 10 10 HOUSTON (IAH) 36 31 59 42 67 / 70 10 10 10 10 GALVESTON (GLS) 37 37 55 48 64 / 70 10 10 10 10 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...WINTER STORM WARNING UNTIL NOON CST TODAY FOR THE FOLLOWING ZONES: AUSTIN...BRAZORIA...BRAZOS...BURLESON...CHAMBERS... COLORADO...FORT BEND...GALVESTON...GRIMES...HARRIS... HOUSTON...JACKSON...LIBERTY...MADISON...MATAGORDA... MONTGOMERY...POLK...SAN JACINTO...TRINITY...WALKER... WALLER...WASHINGTON...WHARTON. WIND ADVISORY UNTIL 9 AM CST THIS MORNING FOR THE FOLLOWING ZONES: BRAZORIA...CHAMBERS...GALVESTON...JACKSON... MATAGORDA. WIND ADVISORY UNTIL 6 AM CST EARLY THIS MORNING FOR THE FOLLOWING ZONES: FORT BEND...HARRIS...WHARTON. GM...SMALL CRAFT ADVISORY UNTIL NOON CST TODAY FOR THE FOLLOWING ZONES: GALVESTON BAY...MATAGORDA BAY...WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS FROM HIGH ISLAND TO FREEPORT OUT 20 NM. SMALL CRAFT ADVISORY UNTIL 5 PM CST THIS AFTERNOON FOR THE FOLLOWING ZONES: WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL 20 NM TO 60 NM...WATERS FROM HIGH ISLAND TO FREEPORT 20 TO 60 NM. && $$ DISCUSSION...43
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1150 PM CST THU JAN 23 2014 .DISCUSSION... 06Z AVIATION DISCUSSION BELOW. && .AVIATION... NO MAJOR CHANGES TO THIS LATEST PACKAGE. STILL EXPECTING THIS WINTRY MIX TO CONTINUE THROUGH THE MID TO LATE MORNING HOURS. AS THE EARLY PRE-DAWN COLUMN COOLS FROM EVAPORATIVE COOLING (FROM LIGHT PRECIPITATION) AND COLD AIR ADVECTION...LIGHT RAIN OR SLEET WILL TRANSITION OVER TO LIGHT SNOW ACROSS MANY OF THE INTERIOR TERMINALS. THERE IS A DECENT POSSIBILITY THAT THE (NEAR) COASTAL HUBS WILL ALSO EXPERIENCE EARLY MORNING SNOWFALL. HIGH REZ MODELING DEPICTS A SOUTHWEST-TO-NORTHEAST FILL IN OF -PLSN OR -SN FROM AROUND 09Z THROUGH 13-15Z ACROSS THE CENTRAL AND SOUTHERN TERMINALS. WINTER PRECIPITATION AND AMPED NORTHEASTERLIES WILL BEGIN TO TAPER OFF FROM NORTH TO SOUTH THROUGH LATE MORNING. CEILINGS LIFT TO VFR THROUGH LATE AFTERNOON. PREDOMINANTLY CLEAR SKIES AND LIGHT VRB WINDS BY EARLY EVENING. THUS...THE NEXT 8 HOURS WILL BE THE WORST OF IT WITH GRADUAL IMPROVEMENT FROM LATE MORNING INTO THE AFTERNOON HOURS. 31 && .PREV DISCUSSION... /ISSUED 951 PM CST THU JAN 23 2014/ DISCUSSION... MID EVENING TEMPERATURES RANGE FROM THE UPPER 20S TO AROUND 30 NORTHWEST (AROUND THE CLL AND CALDWELL AREA) TO THE MID 30S IN THE HOUSTON AREA TO THE MID TO UPPER 30S AT THE COAST. WINDS ARE HOWLING AND GUSTY...GENERALLY 15 TO 20 MPH WELL INLAND...20 TO 30 MPH ACROSS THE COASTAL COUNTIES AND AT THE BEACHES. WIND ADVISORY REMAINS IN EFFECT FROM ROUGHLY ALONG AND SOUTH OF HIGHWAY 59. GALE WARNINGS REMAIN IN EFFECT FOR ALL COASTAL WATERS. AS FOR PRECIP...THERE HAS BEEN A MIX OF FREEZING RAIN AND SLEET WITH AN OCCASIONAL SHOW FLURRY REPORTED ON SURFACE OBS AND VIA SOCIAL MEDIA. EXPECT TEMPERATURES TO CONTINUE TO FALL AS THE NIGHT PROGRESSES...AND THIS SHOULD ALLOW FOR MORE FROZEN PRECIPITATION TO DEVELOP. WHILE RADAR IS TRENDING A SLIGHT DECREASE IN COVERAGE...MODELS INDICATE MORE DEVELOPMENT FROM ROUGHLY I-10 SOUTHWARD AND OFF THE COAST THROUGH THE OVERNIGHT HOURS. BASED ON THIS EXPECTATION...WILL NOT MAKE ANY MAJOR CHANGES TO THE CURRENT FORECAST. STAY SAFE! 42 && PREV DISCUSSION... /ISSUED 630 PM CST THU JAN 23 2014/ DISCUSSION... 00Z AVIATION DISCUSSION BELOW. AVIATION... A WINTRY TAF WITH PERIODS OF -RA...TRANSITIONING OVER TO SLEET- RAIN...WITH A MODERATE LIKELIHOOD OF FREEZING RAIN AND SNOW FLURRIES FROM GENERALLY THE CITY NORTHWARD. FORECAST HAS MANY INTERIOR HUBS FALLING TO OR BELOW FREEZING JUST BEFORE MIDNIGHT .COASTAL TERMINALS FALLING TO FREEZING DURING THE PRE-DAWN HOURS. MODEL SOUNDINGS DEPICT A DEEP ENOUGH SUB-FREEZING LAYER WITHIN THIS OVERRUNNING SITUATION TO ALLOW FOR MID-LAYER LIGHT RAIN TO PARTIALLY FREEZE INTO SLEET ON ITS WAY THROUGH IT. LIGHT RAIN OR SLEET FALLING ONTO COLD SURFACES (I.E., AIRCRAFT HULLS, ELEVATED METALLIC STRUCTURES) MAY FREEZE UPON CONTACT. THIS FROZEN MIXTURE MAY LINGER ON INTO THE MID-LATE MORNING HOURS UNTIL DRY AIR MOVES IN AND SCOURS OUT THE MID TO LOWER LAYERS. EARLY PERIOD MVFR DECKS FALLING TO IFR THROUGH THE OVERNIGHT HOURS WITH QUITE THE ROBUST NORTHEAST WIND IN THE 15-25G35 KT RANGE THROUGH THE PRE-DAWN HOURS. 31 && PREV DISCUSSION... /ISSUED 354 PM CST THU JAN 23 2014/ WINTER STORM WARNING IN EFFECT UNTIL NOON FRIDAY... DISCUSSION... COLD FRONT HAS PUSHED OFF THE COAST AND TEMPERATURES CONTINUE TO DROP. THERE IS STILL QUITE A BIT OF PRECIPITATION ACROSS THE AREA AND EVEN SOME REPORTS OF SNOW MIXED WITH RAIN. UPPER LEVEL TROUGH OVER THE PLAINS SHOULD SLOWLY SWING TOWARDS N TX TONIGHT WITH FAVORABLE JET DYNAMICS FOR LARGE SCALE LIFT. COLD AIRMASS WILL CONTINUE TO FILTER INTO THE REGION WITH TEMPS DROPPING BELOW FREEZING CONROE NORTHWARD MAINLY AROUND 9PM. FREEZING TEMPS THEN WORK NORTH TO SOUTH ACROSS THE AREA AFTER MIDNIGHT FOR HOUSTON ALTHOUGH IT COULD HAPPEN SOONER WITH PRECIP FALLING AND WET BULB THERMODYNAMIC PROCESSES. THERE IS QUITE A BIT OF DRY AIR JUST NORTH OF THE AREA WITH DEWPOINTS IN THE TEENS. MODELS CONSISTENTLY KEEPING THIS DRIER AIR OUT OF THE AREA OR SLOWLY MOVING IN MIXING WITH MOIST BOUNDARY LAYER AS IT DOES SO. THE RESULT IS FAVORABLE CONDITIONS FOR ONGOING PRECIPITATION. AS JET DYNAMICS SET UP OVER THE AREA WITH RIGHT ENTRANCE REGION OVER THE AREA...NAM CONTINUES TO BE ROBUST WITH ISENTROPIC LIFT. GFS NOT AS MUCH BUT STILL ENOUGH TO GENERATE A SOLID 0.1 TO 0.25 OF PRECIPITATION OVER THE AREA THROUGH 12Z FRI. NAM ALSO HAS QUITE A BIT OF FRONTOGENESIS IN SEVERAL LAYERS MAINLY 850MB-700MB PEAKING AROUND 06Z THROUGH 12Z. THE MAIN ISSUE BEFORE WAS WOULD THERE BE ENOUGH LIFT FOR PRECIP AND WHETHER DRY SUB FREEZING LAYER WOULD KEEP PRECIP FROM REACHING GROUND. THAT HAS CHANGED AND AS A RESULT WINTER STORM WARNING CRITERIA LOOKS TO BE MET ACROSS THE AREA. LIFT AND FORCING SEEMS TO WEAKEN AFTER 18Z FRI SO EXPECT PRECIP TO END IN THE AFTERNOON AND EVENING. NAM STILL HOLDS ONTO PRECIP LONGER ALONG THE COAST IN THE AFTERNOON THAN THE GFS/ECMWF. PRECIPITATION TYPE...THINK AREAS NORTH OF CONROE WILL START WITH RAIN TRANSITION TO MIX SLEET/FZRA UNTIL 06Z FRI. MAY THEN SEE A TRANSITION TO SNOW/SLEET AFTER MIDNIGHT UNTIL THE MORNING HOURS. POSSIBLE TO HAVE A BAND OF 1 INCH SNOW ACCUMULATIONS FROM CALDWELL/COLLEGE STATION ACROSS HUNTSVILLE TO LIVINGSTON. ICE ACCUMULATION MAY NOT BE THAT MUCH BUT STILL ENOUGH TO MAKE A MESS OF TRAVEL CONDITIONS. PRECIPITATION TYPE...BASICALLY CONROE SOUTH THOUGH HOUSTON TO THE COAST EXPECT RAIN GOING TO FZRA/SLEET APPROACHING MIDNIGHT WHEN TEMPS DROP BELOW FREEZING AT SFC. MODEL SOUNDINGS ARE NOT ALL THAT SUPPORTIVE OF SNOW BUT SUPPOSE A FLAKE OR TWO COULD MIX IN WITH SLEET. ISENTROPIC LIFT WITH WARM NOSE AROUND 850-800MB IN SOUNDINGS SHOULD SUPPORT SLEET AND DEPENDING ON DEPTH OF SUB-FREEZING LAYER...FREEZING RAIN CLOSER TO THE COAST. POSSIBLE TO GET FREEZING RAIN AS FAR SOUTH AS GALVESTON BY 12Z FRI WHICH COULD CAUSE FURTHER TRAVEL ISSUES. ACCUMULATIONS...OVERALL EXPECT HALF INCH TO 1 INCH OF SNOW FOR NORTHERN AREAS AS OUTLINED ABOVE. GIVE MESO MODEL OUTPUT FROM TX TECH WRF AND RECENT HRRR RUNS...EVEN 2 INCHES MAY BE POSSIBLE IN A FEW SPOTS. FOR ICE ACCUMULATIONS GENERAL 0.05 TO 0.2 INCHES OF ICE WILL BE POSSIBLE MAINLY ALONG I-10 AND US59 AND BACK TOWARDS HOUSTON. LOWER AMOUNTS WILL BE POSSIBLE ALONG THE COAST BUT STILL A RISK MAINLY FRIDAY MORNING. WEEKEND DOES LOOK TO BE WARMER AFTER FRIDGID FRIDAY. NEXT FRONT STILL ON SCHEDULE FOR MONDAY WHICH WILL PUT MIN TEMPS BACK BELOW FREEZING FOR TUESDAY AND WEDNESDAY. DOES NOT LOOK LIKE A WINTER WEATHER SCENARIO AS ANY PRECIP WILL BE PUSHED OUT WITH FRONT. 39 && .MARINE... WENT AHEAD WITH THE GALE WARNING FOR ALL OUR MARINE AREAS WITH THE MORNING UPDATE AND NO CHANGES FROM THE CURRENT CONFIGURATIONS WILL BE COMING WITH THIS NEXT PACKAGE. STILL EXPECTING WINDS/SEAS TO DE- CREASE BY TOMORROW/FRI AFTN AS HIGH PRESSURE SETTLES OVER THE AREA FROM THE NORTH. A LIGHT ONSHORE FLOW TO RETURN LATE IN THE WEEKEND BUT SHOULD BE SHORT-LIVED AS ANOTHER COLD FRONT MOVES ACROSS SE TX AND INTO THE COASTAL WATERS SUN OVERNIGHT/VERY EARLY MON. 41 && .PRELIMINARY POINT TEMPS/POPS... COLLEGE STATION (CLL) 26 36 29 60 41 / 70 30 10 10 10 HOUSTON (IAH) 28 35 30 60 41 / 80 50 10 10 10 GALVESTON (GLS) 30 37 36 56 48 / 70 60 20 10 10 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...WINTER STORM WARNING UNTIL NOON CST FRIDAY FOR THE FOLLOWING ZONES: AUSTIN...BRAZORIA...BRAZOS...BURLESON...CHAMBERS... COLORADO...FORT BEND...GALVESTON...GRIMES...HARRIS... HOUSTON...JACKSON...LIBERTY...MADISON...MATAGORDA... MONTGOMERY...POLK...SAN JACINTO...TRINITY...WALKER... WALLER...WASHINGTON...WHARTON. WIND ADVISORY UNTIL 6 AM CST FRIDAY FOR THE FOLLOWING ZONES: BRAZORIA...CHAMBERS...FORT BEND...GALVESTON...HARRIS... JACKSON...MATAGORDA...WHARTON. GM...SMALL CRAFT ADVISORY FROM 3 AM TO NOON CST FRIDAY FOR THE FOLLOWING ZONES: GALVESTON BAY...MATAGORDA BAY...WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL OUT 20 NM... WATERS FROM HIGH ISLAND TO FREEPORT OUT 20 NM. GALE WARNING UNTIL 3 AM CST FRIDAY FOR THE FOLLOWING ZONES: GALVESTON BAY...MATAGORDA BAY...WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL 20 NM TO 60 NM...WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS FROM HIGH ISLAND TO FREEPORT 20 TO 60 NM...WATERS FROM HIGH ISLAND TO FREEPORT OUT 20 NM. SMALL CRAFT ADVISORY FROM 3 AM TO 5 PM CST FRIDAY FOR THE FOLLOWING ZONES: WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL 20 NM TO 60 NM...WATERS FROM HIGH ISLAND TO FREEPORT 20 TO 60 NM. && $$ DISCUSSION...42 AVIATION/MARINE...31
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
1201 PM EST SAT JAN 25 2014 .SYNOPSIS... A DEEP AND EXPANSIVE AREA OF LOW PRESSURE...ANCHORED ACROSS HUDSON BAY...WILL REMAIN IN PLACE ACROSS THE EASTERN TWO-THIRDS OF THE U.S. INTO THE LATER HALF OF THE WEEK BEFORE FINALLY BEGINNING RETREAT SOMEWHAT TO THE NORTH. A SERIES OF ALBERTA CLIPPERS WILL CONTINUE TO SEND SURGES OF ARCTIC AIR INTO THE REGION...ALSO PROVIDING FOR MINOR TO MODERATE ACCUMULATIONS OF UPSLOPE SNOW IN THE ALLEGHANYS. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... AS OF 1120 AM EST SATURDAY... EXPANDED WIND ADVISORY TO INCLUDE THE NEW RIVER VALLEY AND SOUTHWEST MOUNTAINS OF SOUTHWEST VIRGINIA. AS OF 940 AM EST SATURDAY... NO CHANGES IN HEADLINES OF WINTER WEATHER ADVISORIES...WIND AND WIND CHILL ADVISORIES AND RED FLAG WARNING IN EFFECT. ROBUST ALBERTA CLIPPER IS TRACKING SOUTHEAST ACROSS THE REGION TODAY. WITH KFCX WSR-88D LOOP SHOWING SOME LIGHT RETURNS IN THE EAST...EXPANDED THE SNOW FLURRIES INTO THE PIEDMONT. REGIONAL RADAR IMAGES SHOWED A LARGE AREA OF SNOW ACROSS EASTERN KENTUCKY AND TENNESSEE THIS MORNING. HRRR AND RNK WRFARW STILL HIGHLIGHT THE BEST FOCUS FOR SNOW SHOWERS WILL OCCUR IN THE WESTERN MOUNTAINS. WILL MONITER THE RADAR THIS AFTERNOON FOR ADJUSTMENTS TO SNOW AND ITS ACCUMULATIONS. MADE SOME MINOR ADJUSTMENTS IN TEMPERATURES...AND POPS FOR THIS MORNING INTO THIS AFTERNOON. MORE CHANGES LATER TODAY WITH THIS ACTIVE WEATHER PATTERN. AS OF 530 AM EST SATURDAY... SOMEWHAT COMPLICATED FORECAST TODAY WITH MULTIPLE CONCERNS. MAIN SYNOPTIC FEATURE THROUGH THE NEAR TERM IS A STRONG ALBERTA CLIPPER THAT WILL MOVE RAPIDLY THROUGH THE CWA THIS MORNING INTO THE AFTERNOON. VERY COLD ARCTIC AIR PRECEDES THIS SYSTEM WITH ALL AREAS WELL BELOW FREEZING AND WELL BELOW NORMAL YET AGAIN THIS MORNING. LWB AT -5F...WITH MOST AREAS OUTSIDE THE PIEDMONT IN THE SINGLE DIGITS OR 10 TO 15F RANGE...PIEDMONT IN THE 15 TO 22 RANGE. SOUTHWEST WINDS WILL BRIEFLY BRING SOME WARMING INTO THE AREA TODAY...BUT IT INDEED BE VERY BRIEF AS THE -20C 850MB ISOTHERM RAPIDLY SURGES BACK TOWARD THE AREA TONIGHT. THIS ALBERTA CLIPPER ACTUALLY RESULTS IN FOUR WEATHER CONCERNS THROUGH TONIGHT...WIND CHILL...UPSLOPE SNOWFALL...STRONG GUSTY WINDS IN THE MOUNTAINS OF NC/FAR SW VA...AND HIGH FIRE DANGER ACROSS THE NC PIEDMONT. SNOWFALL POTENTIAL WILL MAINLY BE LATE MORNING THROUGH EARLY EVENING...LINGERING OVERNIGHT IN THE USUAL FAVORED UPSLOPE AREAS OF EASTERN WV. WITH SOUTHWEST WINDS AND WELL BELOW FREEZING TEMPERATURES...THERE MAY BE A LITTLE MORE SNOWFALL IN SW VA THAN CURRENTLY ADVERTISED. WILL NEED TO WATCH THAT THROUGH THE MORNING...BUT OVERALL EXPECTING 1-2 INCHES FAR SW VA/NW NC AND 2-4 INCHES TAZEWELL VA NORTH TO GREENBRIER...ESPECIALLY WESTERN GREENBRIER AS USUAL...WHERE A FEW SPOTS COULD RECEIVE UP TO 5 INCHES BY SUN MORNING. SW WINDS WILL INCREASE THROUGH THE LATE MORNING AND AFTERNOON TO 15 TO 25 MPH AND GUSTY...ESPECIALLY ACROSS SW VA/NW NC...BUT THE MAIN INCREASE IN WIND WILL COME BEHIND THE CLIPPER THIS AFTERNOON AND ESPECIALLY AFT 00Z AND AFTER THE WINDS VEER MORE TO THE W OR WNW. FOR THIS CONCERN...HAVE POSTED A WIND ADVISORY FOR OUR NC MOUNTAIN COUNTIES AND THE GRAYSON HIGHLANDS...WHERE SOME GUSTS IN THE 00Z- 06Z TIME FRAME TONIGHT COULD APPROACH HIGH WIND WARNING CRITERIA. FINAL CONCERN IS ENHANCED FIRE DANGER ACROSS OUR NC PIEDMONT COUNTIES. NCFS REQUESTED FWF/RFW FRIDAY AFTERNOON/EVENING AND WITH 10-HR FUEL MOISTURE VALUES DURING THE AFTERNOON FRI DROPPING INTO THE 6-7 PERCENT RANGE COMBINED WITH THE WINDS AND LOW RH VALUES OF 15-20 PERCENT THIS AFTERNOON...THANKS TO THE RESIDUAL ARCTIC AIR MASS AND ADDITIONAL DOWNSLOPE DRYING...COMBINED WITH THE EXPECTED WINDS...CONDITIONS CERTAINLY MEET RFW CRITERIA. THUS...HAVE MATCHED GSP/RAH WITH RFW. WILL ISSUE AN SPS FOR ENHANCED FIRE DANGER FOR ALLEGHANY AND WILKES COUNTY NC WHERE FUELS ARE WETTER AND RH VALUES WILL BE A LITTLE HIGHER. FOR TEMPERATURES...GRIDDED MODEL GFS/ECMWF TEMPS SEEM TO HAVE A BETTER HANDLE ON THE TEMPERATURE TREND THIS AFTERNOON/TONIGHT AND THE MINIMUMS FOR SUN. HOWEVER...THIS RESULTED IN READINGS AND ESPECIALLY WIND CHILL READINGS TOO LOW AND OUT OF TOLERANCE WITH NEIGHBORS. HAVE COMPROMISED WITH A GFS MOS/ECMWF MOS/GRIDDED GFS SFC T BLEND...STILL YEILDING BELOW ZERO TEMPS ACROSS MUCH OF GREENBRIER COUNTY EARLY SUN...AND WIND CHILLS OF -5F TO -20F ACROSS MUCH OF THE CWA WEST OF I-81 AND I-77 LATE TONIGHT AND EARLY SUN. FOR THIS REASON...HAVE POSTED A NEW WIND CHILL ADVISORY FOR THESE AREAS. IF TEMPS TREND MORE TOWARD ADVERTISED GFS/ECMWF GRIDDED SFC T...A WIND CHILL WARNING MAY BE NEEDED FOR BATH/GREENBRIER/SUMMERS COUNTY...AND POSSIBLY OTHERS DOWN INTO SW VA AND NW NC. && .SHORT TERM /6 PM THIS EVENING THROUGH MONDAY/... AS OF 430 AM EST SATURDAY... ANOTHER STRONG ARCTIC FRONT WILL CROSS THE REGION ON MONDAY. AGAIN EXPECTING A NARROW BAND OF SNOW SHOWERS JUST AHEAD AND ALONG IT...WITH A PERIOD OF UPSLOPE SNOW BEHIND IT MONDAY AFTERNOON. DOWNSLOPE FLOW WITH THIS BOUNDARY SHOULD ALLOW THE PIEDMONT/SOUTHSIDE TO RISE THROUGH THE 40S...WITH FALLING TEMPS FURTHER NORTH AND WEST...WITH MORNING HIGHS ACROSS SE WEST VA AS TEMPS PLUMMET TO THE TEENS ACROSS THE GREENBRIER VALLEY BY LATE AFTERNOON. EXPECTING A LIGHT SNOWFALL...RIGHT AROUND MONDAY MORNING RUSH HOUR...WITH LESS THAN AN INCH MOST SPOTS...BUT AN INCH OR TWO ABOVE 3000 FEET ACROSS SW VA AND SE WEST VA. WITH H85 TEMPS TO -27C ALONG NW GREENBRIER MONDAY NIGHT...AND SNOWCOVER...USED THE 2M GFS TEMPS FOR MINS...AS THEY HAVE BEEN VERIFYING MUCH BETTER DURING THESE ARCTIC BLASTS THAN THE MOS FOR MINS. GFS/NAM GUIDANCE BUSTED BY 10F JUST A COUPLE DAYS BEFORE THIS MOST RECENT ARCTIC OUTBREAK. FOLLOWED THE SAME IDEA FOR TUESDAY NIGHT WITH STRONG HIGH PRESSURE NEARBY AND DECOUPLING EXPECTED. THIS MAY PUT THE SHELTERED VALLEYS AROUND 5 BELOW ZERO BOTH NIGHTS. HIGH TEMPS TUESDAY WILL STRUGGLE TO REACH 10F IN SE WEST VA. WIND CHILL WARNINGS/ADVISORIES WILL BE NECESSARY AGAIN EARLY NEXT WEEK. && .LONG TERM /MONDAY NIGHT THROUGH FRIDAY/... AS OF 300 PM EST FRIDAY... THE MASSIVE POLAR LOW OVER HUDSON BAY CANADA...OFTEN REFERRED TO AS THE POLAR VORTEX...WILL MAINTAIN ITS POSITION MONDAY NIGHT INTO TUESDAY...AS WELL AS ITS INFLUENCE OVER OUR WEATHER PATTERN. WILL START MONDAY EVENING OFF WITH HIGH PRESSURE BUILDING INTO OUR AREA FROM THE WEST...IN THE WAKE OF A DEPARTING COLD FRONT. MONDAY NIGHT TEMPERATURES WILL FALL RAPIDLY...TO BOTTOM OUT IN THE SINGLE DIGITS ACROSS THE MOUNTAINS...AND IN THE LOW TO MID TEENS EAST OF THE BLUE RIDGE. AS SUCH...WILL START TUESDAY MORNING OFF WITH WIND CHILLS ACROSS THE MOUNTAINS EASILY IN THE ADVISORY TERRITORY OF -5F TO -15F...POSSIBLY DROPPING TO -20F OR LOWER ACROSS WESTERN GREENBRIER COUNTY. TEMPERATURES TUESDAY AFTERNOON WILL REBOUND SOMEWHAT...BUT WILL REMAIN WELL BELOW FREEZING AREAWIDE. THERE WAS CONCERN YESTERDAY OF A COASTAL LOW DEVELOPING TUESDAY NIGHT AND WEDNESDAY...SPREADING SNOW ACROSS OUR AREA. TODAY...BOTH THE GFS AND ECMWF FORECAST MODELS HAVE BACKED OFF ON THIS EVENT...ALTHOUGH THE ECMWF STILL INDICATES THE POTENTIAL FOR MODEST SNOWFALL ACROSS THE PIEDMONT ON TUESDAY NIGHT. WILL MAINTAIN A SLIGHT CHANCE OF SNOW IN THE FORECAST...AS AM HESITANT TO MAKE A DRASTIC CHANGE UNTIL THE MODELS GET A BETTER HANDLE ON THIS EVENT. FOR WEDNESDAY AND THURSDAY...THE FORECAST LOOKS DRY...WITH A GRADUAL WARMING TREND AS THE POLAR LOW IS FINALLY SHOWING SIGNS OF BREAKING DOWN. AS SUCH...WILL SEE A SLIGHT WARMING TREND FOR WEDNESDAY AND THURSDAY BY A FEW DEGREES EACH DAY...ALTHOUGH TEMPERATURES WILL STILL BE SEVERAL DEGREES BELOW AVERAGE FOR LATE JANUARY. THE WARMING TRENDS IS EXPECTED TO CONTINUE INTO THE WEEKEND AS THE POLAR LOW RETREATS FURTHER AWAY FROM OUR REGION. && .AVIATION /18Z SATURDAY THROUGH THURSDAY/... AS OF 1201 PM EST SATURDAY... AN UPPER LEVEL DISTURBANCE WILL CROSS THE REGION THIS AFTERNOON INTO TONIGHT. CONDITIONS WILL WORSEN TO IFR/MVFR THIS AFTERNOON WITH ASSOCIATED SNOW SHOWERS MAINLY ALONG AND WEST OF A KTNB-KMKJ-KHSP LINE...INCLUDING THE TAF SITES OF KBLF AND KLWB. EAST OF THIS AREA TO THE CREST OF THE BLUE RIDGE...THE IFR/MVFR CONDITIONS WILL PATCHY AMONG A MORE PREDOMINATE LOW END VFR CEILING AND SCATTERED SNOW SHOWERS. FLIGHT CATEGORIES WILL IMPROVE TO VFR AT MOST LOCATIONS AFTER ROUGHLY 02Z/8PM SUNDAY AS THE TROUGH AXIS SHIFTS EAST. WINDS WILL BE GUSTY THIS AFTERNOON INTO TONIGHT ESPECIALLY ACROSS THE MOUNTAINS. THE HIGHEST TERRAIN WILL EXPERIENCE SOME GUSTS AROUND 35 KTS. BEHIND THE TROUGH AXIS...850 MB WINDS INCREASE FROM THE NORTHWEST WITH 50KTS COMMON ACROSS THE AREA AT THIS LEVEL. AT THE SURFACE...GUSTS WILL APPROACH 40 TO 45 KTS AT THE HIGHER ELEVATIONS ACROSS THE MOUNTAINS. EAST OF THE BLUE RIDGE...SURFACE GUSTS AROUND 25KTS WILL BE MORE COMMON. MEDIUM CONFIDENCE ON CIGS...VISIBILITY AND WIND DURING THE PERIOD. EXTENDED AVIATION DISCUSSION... THE WEATHER PATTERN FOR NEXT WEEK REMAINS UNCHANGED. FLOW ALOFT WILL REMAIN PROGRESSIVE...PRIMARILY FROM THE NORTHWEST WITH PERIODIC SHORTWAVE TROUGHS RIDING ALONG THE FLOW AND MOVING ACROSS OR NEAR OUR REGION. EACH OF THESE WILL HAVE THE POTENTIAL OF PRODUCING MVFR CIGS AND SNOW SHOWERS ACROSS THE MOUNTAINS...WITH AN ASSOCIATED INCREASE IN NORTHWEST WINDS CONCURRENT AND IN THE WAKE OF EACH SYSTEM. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO 8 AM EST SUNDAY FOR VAZ007-009>016-018>020. WIND ADVISORY UNTIL 6 AM EST SUNDAY FOR VAZ007-009>017. WINTER WEATHER ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR VAZ007. NC...WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO 8 AM EST SUNDAY FOR NCZ001-002-018. WIND ADVISORY UNTIL 6 AM EST SUNDAY FOR NCZ001-002-018. RED FLAG WARNING UNTIL 6 PM EST THIS EVENING FOR NCZ003>006- 020. WV...WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO 8 AM EST SUNDAY FOR WVZ042>045. WINTER WEATHER ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR WVZ042- 043-045. && $$ SYNOPSIS...RAB NEAR TERM...KK/RAB SHORT TERM...KM LONG TERM...NF AVIATION...DS/KK
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
944 AM EST SAT JAN 25 2014 .SYNOPSIS... A DEEP AND EXPANSIVE AREA OF LOW PRESSURE...ANCHORED ACROSS HUDSON BAY...WILL REMAIN IN PLACE ACROSS THE EASTERN TWO-THIRDS OF THE U.S. INTO THE LATER HALF OF THE WEEK BEFORE FINALLY BEGINNING RETREAT SOMEWHAT TO THE NORTH. A SERIES OF ALBERTA CLIPPERS WILL CONTINUE TO SEND SURGES OF ARCTIC AIR INTO THE REGION...ALSO PROVIDING FOR MINOR TO MODERATE ACCUMULATIONS OF UPSLOPE SNOW IN THE ALLEGHANYS. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... AS OF 940 AM EST SATURDAY... NO CHANGES IN HEADLINES OF WINTER WEATHER ADVISORIES...WIND AND WIND CHILL ADVISORIES AND RED FLAG WARNING IN EFFECT. ROBUST ALBERTA CLIPPER IS TRACKING SOUTHEAST ACROSS THE REGION TODAY. WITH KFCX WSR-88D LOOP SHOWING SOME LIGHT RETURNS IN THE EAST...EXPANDED THE SNOW FLURRIES INTO THE PIEDMONT. REGIONAL RADAR IMAGES SHOWED A LARGE AREA OF SNOW ACROSS EASTERN KENTUCKY AND TENNESSEE THIS MORNING. HRRR AND RNK WRFARW STILL HIGHLIGHT THE BEST FOCUS FOR SNOW SHOWERS WILL OCCUR IN THE WESTERN MOUNTAINS. WILL MONITER THE RADAR THIS AFTERNOON FOR ADJUSTMENTS TO SNOW AND ITS ACCUMULATIONS. MADE SOME MINOR ADJUSTMENTS IN TEMPERATURES...AND POPS FOR THIS MORNING INTO THIS AFTERNOON. MORE CHANGES LATER TODAY WITH THIS ACTIVE WEATHER PATTERN. AS OF 530 AM EST SATURDAY... SOMEWHAT COMPLICATED FORECAST TODAY WITH MULTIPLE CONCERNS. MAIN SYNOPTIC FEATURE THROUGH THE NEAR TERM IS A STRONG ALBERTA CLIPPER THAT WILL MOVE RAPIDLY THROUGH THE CWA THIS MORNING INTO THE AFTERNOON. VERY COLD ARCTIC AIR PRECEDES THIS SYSTEM WITH ALL AREAS WELL BELOW FREEZING AND WELL BELOW NORMAL YET AGAIN THIS MORNING. LWB AT -5F...WITH MOST AREAS OUTSIDE THE PIEDMONT IN THE SINGLE DIGITS OR 10 TO 15F RANGE...PIEDMONT IN THE 15 TO 22 RANGE. SOUTHWEST WINDS WILL BRIEFLY BRING SOME WARMING INTO THE AREA TODAY...BUT IT INDEED BE VERY BRIEF AS THE -20C 850MB ISOTHERM RAPIDLY SURGES BACK TOWARD THE AREA TONIGHT. THIS ALBERTA CLIPPER ACTUALLY RESULTS IN FOUR WEATHER CONCERNS THROUGH TONIGHT...WIND CHILL...UPSLOPE SNOWFALL...STRONG GUSTY WINDS IN THE MOUNTAINS OF NC/FAR SW VA...AND HIGH FIRE DANGER ACROSS THE NC PIEDMONT. SNOWFALL POTENTIAL WILL MAINLY BE LATE MORNING THROUGH EARLY EVENING...LINGERING OVERNIGHT IN THE USUAL FAVORED UPSLOPE AREAS OF EASTERN WV. WITH SOUTHWEST WINDS AND WELL BELOW FREEZING TEMPERATURES...THERE MAY BE A LITTLE MORE SNOWFALL IN SW VA THAN CURRENTLY ADVERTISED. WILL NEED TO WATCH THAT THROUGH THE MORNING...BUT OVERALL EXPECTING 1-2 INCHES FAR SW VA/NW NC AND 2-4 INCHES TAZEWELL VA NORTH TO GREENBRIER...ESPECIALLY WESTERN GREENBRIER AS USUAL...WHERE A FEW SPOTS COULD RECEIVE UP TO 5 INCHES BY SUN MORNING. SW WINDS WILL INCREASE THROUGH THE LATE MORNING AND AFTERNOON TO 15 TO 25 MPH AND GUSTY...ESPECIALLY ACROSS SW VA/NW NC...BUT THE MAIN INCREASE IN WIND WILL COME BEHIND THE CLIPPER THIS AFTERNOON AND ESPECIALLY AFT 00Z AND AFTER THE WINDS VEER MORE TO THE W OR WNW. FOR THIS CONCERN...HAVE POSTED A WIND ADVISORY FOR OUR NC MOUNTAIN COUNTIES AND THE GRAYSON HIGHLANDS...WHERE SOME GUSTS IN THE 00Z- 06Z TIME FRAME TONIGHT COULD APPROACH HIGH WIND WARNING CRITERIA. FINAL CONCERN IS ENHANCED FIRE DANGER ACROSS OUR NC PIEDMONT COUNTIES. NCFS REQUESTED FWF/RFW FRIDAY AFTERNOON/EVENING AND WITH 10-HR FUEL MOISTURE VALUES DURING THE AFTERNOON FRI DROPPING INTO THE 6-7 PERCENT RANGE COMBINED WITH THE WINDS AND LOW RH VALUES OF 15-20 PERCENT THIS AFTERNOON...THANKS TO THE RESIDUAL ARCTIC AIR MASS AND ADDITIONAL DOWNSLOPE DRYING...COMBINED WITH THE EXPECTED WINDS...CONDITIONS CERTAINLY MEET RFW CRITERIA. THUS...HAVE MATCHED GSP/RAH WITH RFW. WILL ISSUE AN SPS FOR ENHANCED FIRE DANGER FOR ALLEGHANY AND WILKES COUNTY NC WHERE FUELS ARE WETTER AND RH VALUES WILL BE A LITTLE HIGHER. FOR TEMPERATURES...GRIDDED MODEL GFS/ECMWF TEMPS SEEM TO HAVE A BETTER HANDLE ON THE TEMPERATURE TREND THIS AFTERNOON/TONIGHT AND THE MINIMUMS FOR SUN. HOWEVER...THIS RESULTED IN READINGS AND ESPECIALLY WIND CHILL READINGS TOO LOW AND OUT OF TOLERANCE WITH NEIGHBORS. HAVE COMPROMISED WITH A GFS MOS/ECMWF MOS/GRIDDED GFS SFC T BLEND...STILL YEILDING BELOW ZERO TEMPS ACROSS MUCH OF GREENBRIER COUNTY EARLY SUN...AND WIND CHILLS OF -5F TO -20F ACROSS MUCH OF THE CWA WEST OF I-81 AND I-77 LATE TONIGHT AND EARLY SUN. FOR THIS REASON...HAVE POSTED A NEW WIND CHILL ADVISORY FOR THESE AREAS. IF TEMPS TREND MORE TOWARD ADVERTISED GFS/ECMWF GRIDDED SFC T...A WIND CHILL WARNING MAY BE NEEDED FOR BATH/GREENBRIER/SUMMERS COUNTY...AND POSSIBLY OTHERS DOWN INTO SW VA AND NW NC. && .SHORT TERM /6 PM THIS EVENING THROUGH MONDAY/... AS OF 430 AM EST SATURDAY... ANOTHER STRONG ARCTIC FRONT WILL CROSS THE REGION ON MONDAY. AGAIN EXPECTING A NARROW BAND OF SNOW SHOWERS JUST AHEAD AND ALONG IT...WITH A PERIOD OF UPSLOPE SNOW BEHIND IT MONDAY AFTERNOON. DOWNSLOPE FLOW WITH THIS BOUNDARY SHOULD ALLOW THE PIEDMONT/SOUTHSIDE TO RISE THROUGH THE 40S...WITH FALLING TEMPS FURTHER NORTH AND WEST...WITH MORNING HIGHS ACROSS SE WEST VA AS TEMPS PLUMMET TO THE TEENS ACROSS THE GREENBRIER VALLEY BY LATE AFTERNOON. EXPECTING A LIGHT SNOWFALL...RIGHT AROUND MONDAY MORNING RUSH HOUR...WITH LESS THAN AN INCH MOST SPOTS...BUT AN INCH OR TWO ABOVE 3000 FEET ACROSS SW VA AND SE WEST VA. WITH H85 TEMPS TO -27C ALONG NW GREENBRIER MONDAY NIGHT...AND SNOWCOVER...USED THE 2M GFS TEMPS FOR MINS...AS THEY HAVE BEEN VERIFYING MUCH BETTER DURING THESE ARCTIC BLASTS THAN THE MOS FOR MINS. GFS/NAM GUIDANCE BUSTED BY 10F JUST A COUPLE DAYS BEFORE THIS MOST RECENT ARCTIC OUTBREAK. FOLLOWED THE SAME IDEA FOR TUESDAY NIGHT WITH STRONG HIGH PRESSURE NEARBY AND DECOUPLING EXPECTED. THIS MAY PUT THE SHELTERED VALLEYS AROUND 5 BELOW ZERO BOTH NIGHTS. HIGH TEMPS TUESDAY WILL STRUGGLE TO REACH 10F IN SE WEST VA. WIND CHILL WARNINGS/ADVISORIES WILL BE NECESSARY AGAIN EARLY NEXT WEEK. && .LONG TERM /MONDAY NIGHT THROUGH FRIDAY/... AS OF 300 PM EST FRIDAY... THE MASSIVE POLAR LOW OVER HUDSON BAY CANADA...OFTEN REFERRED TO AS THE POLAR VORTEX...WILL MAINTAIN ITS POSITION MONDAY NIGHT INTO TUESDAY...AS WELL AS ITS INFLUENCE OVER OUR WEATHER PATTERN. WILL START MONDAY EVENING OFF WITH HIGH PRESSURE BUILDING INTO OUR AREA FROM THE WEST...IN THE WAKE OF A DEPARTING COLD FRONT. MONDAY NIGHT TEMPERATURES WILL FALL RAPIDLY...TO BOTTOM OUT IN THE SINGLE DIGITS ACROSS THE MOUNTAINS...AND IN THE LOW TO MID TEENS EAST OF THE BLUE RIDGE. AS SUCH...WILL START TUESDAY MORNING OFF WITH WIND CHILLS ACROSS THE MOUNTAINS EASILY IN THE ADVISORY TERRITORY OF -5F TO -15F...POSSIBLY DROPPING TO -20F OR LOWER ACROSS WESTERN GREENBRIER COUNTY. TEMPERATURES TUESDAY AFTERNOON WILL REBOUND SOMEWHAT...BUT WILL REMAIN WELL BELOW FREEZING AREAWIDE. THERE WAS CONCERN YESTERDAY OF A COASTAL LOW DEVELOPING TUESDAY NIGHT AND WEDNESDAY...SPREADING SNOW ACROSS OUR AREA. TODAY...BOTH THE GFS AND ECMWF FORECAST MODELS HAVE BACKED OFF ON THIS EVENT...ALTHOUGH THE ECMWF STILL INDICATES THE POTENTIAL FOR MODEST SNOWFALL ACROSS THE PIEDMONT ON TUESDAY NIGHT. WILL MAINTAIN A SLIGHT CHANCE OF SNOW IN THE FORECAST...AS AM HESITANT TO MAKE A DRASTIC CHANGE UNTIL THE MODELS GET A BETTER HANDLE ON THIS EVENT. FOR WEDNESDAY AND THURSDAY...THE FORECAST LOOKS DRY...WITH A GRADUAL WARMING TREND AS THE POLAR LOW IS FINALLY SHOWING SIGNS OF BREAKING DOWN. AS SUCH...WILL SEE A SLIGHT WARMING TREND FOR WEDNESDAY AND THURSDAY BY A FEW DEGREES EACH DAY...ALTHOUGH TEMPERATURES WILL STILL BE SEVERAL DEGREES BELOW AVERAGE FOR LATE JANUARY. THE WARMING TRENDS IS EXPECTED TO CONTINUE INTO THE WEEKEND AS THE POLAR LOW RETREATS FURTHER AWAY FROM OUR REGION. && .AVIATION /15Z SATURDAY THROUGH WEDNESDAY/... AS OF 1135 PM EST FRIDAY... HIGH CONFIDENCE OF VFR CONDITIONS THROUGH 12Z/7AM SATURDAY. AN UPPER LEVEL DISTURBANCE WILL CROSS THE REGION DURING THE DAY SATURDAY. CONDITIONS WILL WORSEN TO IFR/MVFR BY 18Z/1PM WITH ASSOCIATED SNOW SHOWERS MAINLY ALONG AND WEST OF A KTNB-KMKJ-KHSP LINE...INCLUDING THE TAF SITES OF KBLF AND KLWB. EAST OF THIS AREA TO THE CREST OF THE BLUE RIDGE...THE IFR/MVFR CONDITIONS WILL PATCHY AMONG A MORE PREDOMINATE LOW END VFR CEILING AND SCATTERED SNOW SHOWERS. FLIGHT CATEGORIES WILL IMPROVE TO VFR AT MOST LOCATIONS AFTER ROUGHLY 02Z/8PM SUNDAY AS THE TROUGH AXIS SHIFTS EAST. WINDS THROUGH THE NIGHT AT MOST LOCATIONS WILL BE LIGHT FROM THE SOUTHWEST. KBLF WILL MAINTAIN A SOUTHWEST WINDS CLOSE TO 10 KTS THAT WILL GET A BIT STRONGER AND GUSTIER TOWARD MORNING. DURING THE DAY SATURDAY...SURFACE GUSTS WILL BECOME MORE COMMONPLACE AFTER ABOUT 15Z/10AM. THE HIGHEST TERRAIN WILL EXPERIENCE SOME GUSTS AROUND 35 KTS. BEHIND THE TROUGH AXIS...850 MB WINDS INCREASE FROM THE NORTHWEST WITH 50KTS COMMON ACROSS THE AREA AT THIS LEVEL. AT THE SURFACE...GUSTS WILL APPROACH 40KTS AT THE HIGHER ELEVATIONS ACROSS THE MOUNTAINS. EAST OF THE BLUE RIDGE...SURFACE GUSTS AROUND 25KTS WILL BE MORE COMMON. AS OF 1234 PM EST FRIDAY... EXTENDED AVIATION DISCUSSION... THE WEATHER PATTERN FOR NEXT WEEK REMAINS UNCHANGED. FLOW ALOFT WILL REMAIN PROGRESSIVE...PRIMARILY FROM THE NORTHWEST WITH PERIODIC SHORTWAVE TROUGHS RIDING ALONG THE FLOW AND MOVING ACROSS OR NEAR OUR REGION. EACH OF THESE WILL HAVE THE POTENTIAL OF PRODUCING MVFR CIGS AND SNOW SHOWERS ACROSS THE MOUNTAINS...WITH AN ASSOCIATED INCREASE IN NORTHWEST WINDS CONCURRENT AND IN THE WAKE OF EACH SYSTEM. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO 8 AM EST SUNDAY FOR VAZ007-009>016-018>020. WIND ADVISORY FROM 1 PM THIS AFTERNOON TO 6 AM EST SUNDAY FOR VAZ015. WINTER WEATHER ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR VAZ007. NC...WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO 8 AM EST SUNDAY FOR NCZ001-002-018. WIND ADVISORY FROM 1 PM THIS AFTERNOON TO 6 AM EST SUNDAY FOR NCZ001-002-018. RED FLAG WARNING UNTIL 6 PM EST THIS EVENING FOR NCZ003>006- 020. WV...WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO 8 AM EST SUNDAY FOR WVZ042>045. WINTER WEATHER ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR WVZ042- 043-045. && $$ SYNOPSIS...RAB NEAR TERM...KK/RAB SHORT TERM...KM LONG TERM...NF AVIATION...DS/KK/PM
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1150 PM CST FRI JAN 24 2014 .UPDATE... ISSUED AT 840 PM CST FRI JAN 24 2014 THE MAIN SNOW BAND IS MOVING THROUGH THE AREA WITH REPORTS COMING IN OF AROUND 1 TO 1.5 INCHES. WITH SURFACE TEMPERATURES AROUND THE FREEZING MARK...THE LIQUID TO SNOW EQUIVALENT RATIO IS LOWER THAN WHAT IT HAS BEEN FOR MANY OF OUR SNOWS THIS WINTER AT AROUND 11 TO 1. THE FIRST WAVE OF SNOW WILL COME TO AN END OVER THE NEXT FEW HOURS AS THE REGION SITS IN THE WARM SECTOR OF AN OCCLUDED LOW PRESSURE SYSTEM. WITH WARMER AIR SITTING OVER NORTHERN IOWA AND SOUTHERN MINNESOTA...THE COLUMN HAS LOST ICE AND FREEZING DRIZZLE IS OCCURRING. THIS WILL LEAD TO SOME ICY ROAD CONDITIONS IN AREAS THAT ROADS HAVE NOT BEEN TREATED. WHILE WINDS ARE PICKING UP OUT OF THE NORTHWEST IN THIS WARM SECTOR ACROSS CENTRAL MINNESOTA...THERE HAS NOT BEEN MANY OBSERVATIONS IN THIS AREA SHOWING ANY LOW VISIBILITIES FROM BLOWING SNOW. THIS IS LIKELY DUE TO THE DRIZZLE THAT IS OCCURRING AND SINCE THIS WAS A HIGHER LIQUID CONTENT SNOWFALL. THE NEXT CONCERN COMES OVERNIGHT AS THE MAIN COLD FRONT...WHICH CURRENTLY EXTENDS FROM DULUTH WEST TOWARD FARGO...PUSHES THROUGH AND BRINGS A SECOND ROUND OF SNOW SHOWERS AND MUCH STRONGER WINDS WITH IT. RADAR/OBS ALONG THIS FRONT SHOW SOME CONVECTIVE LOOKING SNOW SHOWERS THAT ALONG WITH THE STRONGER WINDS COULD CAUSE SOME BRIEF VISIBILITY DROPS DOWN TO LESS THAN A MILE. 25.00Z RAP FORECAST SOUNDINGS ARE SHOWING SOME GUSTS IN THE 35 TO 45 MPH RANGE FOR A FEW HOUR PERIOD WHEN FROPA OCCURS. THIS MATCHES WHAT IS OCCURRING UPSTREAM NEAR DULUTH WHERE SOME OBS HAVE BEEN IN THAT RANGE ALONG THE FRONT. CONDITIONS THEN SHOULD IMPROVE TOWARD DAYBREAK AS THE WINDS DROP DOWN AND SKIES CLEAR OUT AS COLD AIR MOVES BACK IN. && .SHORT TERM...(THIS EVENING THROUGH SATURDAY) ISSUED AT 325 PM CST FRI JAN 24 2014 STRONG WINTER STORM TO IMPACT THE AREA SUNDAY INTO SUNDAY NIGHT WITH NEAR BLIZZARD CONDITIONS POSSIBLE WEST OF THE MISSISSIPPI RIVER. DANGEROUS...POTENTIALLY LIFE THREATENING...WIND CHILLS OF -35 TO -45 EXPECTED ACROSS THE ENTIRE AREA FROM LATE SUNDAY NIGHT THROUGH TUESDAY MORNING. A COLD FRONT WILL PUSH THROUGH THE REGION LATE THIS AFTERNOON THOUGH THIS EVENING BRINING LIGHT SNOW TO THE AREA. SNOW ACCUMULATIONS OF AROUND AN INCH ARE EXPECTED WITH A FEW 1.5 INCH ACCUMULATIONS POSSIBLE. NORTHWEST WINDS WILL INCREASE TO 20 TO 30 MPH WITH GUSTS TO AROUND 40 MPH POSSIBLE IN THE OPEN AREAS OF SOUTHEAST MINNESOTA AND NORTHEAST IOWA. THESE GUSTY NORTHWEST WINDS WILL PRODUCE AREAS OF DRIFTING AND POSSIBLY BLOWING SNOW THAT COULD PRODUCE A FEW SLICK STRETCHES ON AREA ROADS TONIGHT INTO EARLY SATURDAY MORNING. WILL HAVE TO MONITOR THIS CLOSELY THIS EVENING. BREEZY NORTHWEST WINDS WILL BRING AREAS OF BLOWING SNOW TO THE OPEN AREAS OF SOUTHEAST MINNESOTA AND NORTHEAST IOWA EARLY SATURDAY MORNING WITH PATCHY BLOWING SNOW ELSEWHERE. HIGH PRESSURE THEN MOVES OVER THE UPPER MISSISSIPPI RIVER VALLEY FOR A BRIEF BREAK IN THE ACTION SATURDAY AFTERNOON BEFORE A POTENT SYSTEM TAKES AIM ON THE REGION SATURDAY NIGHT INTO SUNDAY. .LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY) ISSUED AT 325 PM CST FRI JAN 24 2014 A STRONG BAROCLINIC ZONE WILL BE IN PLACE OVER THE UPPER MISSISSIPPI RIVE VALLEY SATURDAY NIGHT INTO SUNDAY AS A SHORTWAVE DROPS SOUTH OUT OF THE NORTHERN PLAINS. SURFACE LOW PRESSURE WILL RIDE ALONG THIS ZONE OUT OF NORTH DAKOTA EARLY SATURDAY NIGHT...PUSHING SOUTHEAST INTO THE FORECAST AREA LATE SATURDAY NIGHT INTO SUNDAY MORNING. SNOW WILL OVERSPREAD SOUTHEAST MINNESOTA AND NORTHEAST IOWA MAINLY AFTER MIDNIGHT...THEN PUSHING INTO WESTERN WISCONSIN EARLY SATURDAY MORNING. FLUFFY SNOW ACCUMULATIONS OF 2 TO 4 INCHES ARE EXPECTED WITH THIS SYSTEM AND A WINTER WEATHER ADVISORY WILL LIKELY BE NEEDED. DANGEROUS CONDITIONS DEVELOP SUNDAY AFTERNOON AS A STRONG ARCTIC COLD FRONT RACES ACROSS THE AREA BRINGING NEAR BLIZZARD CONDITIONS TO SOUTHEAST MINNESOTA...NORTHEAST IOWA...AND POSSIBLY FAR SOUTHWEST WISCONSIN. NORTHWEST WINDS WILL INCREASE TO 25 TO 35 MPH WITH GUSTS AROUND 50 MPH POSSIBLE OVER THESE AREAS. THESE WINDS COMBINED WITH THE FLUFFY 2 TO 4 INCHES OF FRESHLY FALLEN SNOW WILL LEAD TO WHITEOUT CONDITIONS AT TIMES ALONG WITH DRIFTING SNOW. LOCATIONS ALONG AND EAST OF THE MISSISSIPPI RIVER WILL ALSO EXPERIENCE AREAS OF BLOWING SNOW AND POSSIBLY HAZARDOUS TRAVEL CONDITIONS AT TIMES. A WINTER STORM WARNING WILL LIKELY BE NEEDED OVER PORTIONS OF SOUTHEAST MINNESOTA AND NORTHEAST IOWA SUNDAY INTO SUNDAY NIGHT. WILL BE ISSUING A WINTER STORM WATCH WITH THIS PACKAGE. A WINTER WEATHER ADVISORY LOOKS LIKELY FOR AREAS ALONG AND EAST OF THE MISSISSIPPI RIVER FROM SUNDAY INTO SUNDAY NIGHT. DANGEROUSLY COLD WIND CHILLS THEN SURGE INTO THE AREA LATE SUNDAY NIGHT INTO MONDAY MORNING WHEN WIND CHILL VALUES WILL FALL TO -30 TO -45. THE COMBINATION OF THESE DANGEROUSLY COLD WIND CHILLS AND NEAR BLIZZARD CONDITIONS OVER WIND PRONE AREAS COULD CREATE A LIFE THREATENING SITUATION IF YOU WERE TO BECOME STRANDED OUTDOORS. DANGEROUSLY COLD WIND CHILLS ARE EXPECTED ACROSS THE ENTIRE FORECAST AREA FROM MIDNIGHT SUNDAY NIGHT ALL THE WAY THROUGH TUESDAY MORNING AND A WIND CHILL WARNING WILL BE NEEDED DURING THIS TIMEFRAME WHEN THE WIND CHILLS DROP TO 35 DEGREES BELOW ZERO OR LOWER. HIGH TEMPERATURES COULD BE AT RECORD LOW VALUES ON MONDAY WITH HIGHS ONLY IN THE SINGLE DIGITS TO TEENS BELOW ZERO. SEE CLIMATE SECTION BELOW FOR MORE INFORMATION. DANGEROUSLY COLD CONDITIONS CONTINUE MONDAY NIGHT WITH LOWS FALLING INTO THE -20 TO -25 RANGE. WIND CHILL VALUES OF -35 TO -45 ARE EXPECTED THROUGH THE NIGHT INTO TUESDAY MORNING. THE ARCTIC AIRMASS MAINTAINS ITS GRIP ON THE REGION ON TUESDAY WITH HIGHS ONLY IN THE SINGLE DIGITS BELOW ZERO. ANOTHER BITTERLY COLD NIGHT IS IN STORE FOR THE REGION TUESDAY NIGHT WITH LOWS IN THE TEENS BELOW ZERO. A WIND CHILL ADVISORY WILL BE NEEDED FROM TUESDAY AFTERNOON THROUGH WEDNESDAY MORNING. HIGH TEMPERATURES LOOK TO WARM INTO TEENS THURSDAY INTO FRIDAY AS WESTERLY FLOW SETS UP OVER THE REGION. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 1150 PM CST FRI JAN 24 2014 CONDITIONS HAVE BEEN IMPROVING AS THE SNOW HAS SHIFTED OFF TO THE SOUTHEAST WITH A COLD FRONT RAPIDLY APPROACHING FROM THE NORTH. A FEW SNOW SHOWERS MAY STILL OCCUR OVER THE NEXT HOUR OR SO...BUT THE CONDITIONS SHOULD MAINLY BE VFR. AS THE COLD FRONT COMES THROUGH...WINDS WILL PICK UP WITH SOME GUSTS IN THE 30 TO 35KT RANGE. THIS COULD BLOW AROUND THE SNOW A LITTLE BIT...BUT RST HAS BEEN BLOWING AT 29KTS WITH VISIBILITIES UP AROUND 8SM. SO...DO NOT THINK THAT THE BLOWING SNOW WILL CAUSE ANY LOWER VIS DESPITE THE SLIGHTLY HIGHER WINDS COMING IN. SKIES WILL CLEAR OUT QUICKLY OVERNIGHT AND STAY THAT WAY THROUGH SATURDAY NIGHT. WINDS WILL GRADUALLY DECREASE THROUGH THE DAY WITH NORTHWEST WINDS BECOMING SOUTHWEST AHEAD OF THE NEXT SYSTEM. THE NEXT QUESTION WILL BE WITH WHETHER ANY SNOW WILL BE MAKING IT INTO RST OR LSE IN THE EVENING. RIGHT NOW...IT LOOKS LIKE IT WILL HOLD OFF...BUT GOING OVERNIGHT THERE WILL LIKELY BE SOME LOWERING CONDITIONS. && .CLIMATE...MONDAY ISSUED AT 325 PM CST FRI JAN 24 2014 WITH FORECAST HIGH TEMPERATURES RUNNING BETWEEN -5 AND -15 ON MONDAY...SEVERAL RECORD COLD HIGH TEMPERATURES MAY BE SET OR TIED. MANY OF THESE RECORDS WERE SET IN EITHER 1902 OR 1972. BELOW ARE THE RECORD COLD HIGH TEMPERATURES FOR THAT DAY. AUSTIN MN -2 IN 1950 CHARLES CITY IA -5 IN 1904 DECORAH IA -4 IN 1902 LA CROSSE WI -4 IN 1902 MEDFORD WI -8 IN 1902 NEILLSVILLE WI -10 IN 1902 PRAIRIE DU CHIEN WI -1 IN 1904 RICHLAND CENTER WI 2 IN 1972 ROCHESTER MN -5 IN 1966 SPARTA WI -1 IN 1972 THEILMAN MN -8 IN 1972 WINONA MN -9 IN 1972 && .ARX WATCHES/WARNINGS/ADVISORIES... WI...WINTER STORM WATCH FROM SUNDAY MORNING THROUGH SUNDAY EVENING FOR WIZ061. MN...WINTER STORM WATCH FROM SUNDAY MORNING THROUGH SUNDAY EVENING FOR MNZ086-087-094-095. IA...WINTER STORM WATCH FROM SUNDAY MORNING THROUGH SUNDAY EVENING FOR IAZ008>011-018-019-029-030. && $$ UPDATE...HALBACH SHORT TERM...WETENKAMP LONG TERM...WETENKAMP AVIATION...HALBACH CLIMATE...BOYNE
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
941 PM CST FRI JAN 24 2014 .UPDATE... THINGS EVOLVING ABOUT AS EXPECTED WITH LARGE SHIELD OF LIGHT SNOW FILLING IN OVER SOUTHERN WISCONSIN AS THE MODELS HAD ADVERTISED IN WARM ADVECTION REGIME RIGHT AHEAD OF COLD FRONT. HRRR IS SHOWING THAT STEADY SNOW IS MAXIMIZED RIGHT NOW AND MOST LOCATIONS ARE IN THE 1-2 MILE RANGE WITH SEVERAL SITES MEASURING. ALREADY LOOKING A LITTLE MORE CONVECTIVE RIGHT ALONG THE FRONT IN THE CENTRAL WISCONSIN AREA...AND HRRR MOVES THAT AREA THROUGH BETWEEN MIDNIGHT AND 3 AM SO NEED TO KEEP DECENT COVERAGE OF SNOW SHOWERS FOR AWHILE. GIVEN THAT STRONGEST WINDS ARE OVER AND STEADY SNOW WILL END AROUND MIDNIGHT IN MOST AREAS...PLAN ON LETTING THE WINTER WEATHER ADVISORY END AT MIDNIGHT. THERE WILL CONTINUE TO BE PATCHY BLOWING SNOW AND DRIFTING SNOW...ESPECIALLY SINCE WE WILL PUT DOWN AN INCH OR SO OF FRESH SNOW. BUT CONDITIONS SEEM TO HAVE BECOME MARGINAL ENOUGH TO LET HEADLINES EXPIRE ON TIME. TEMPERATURES ARE ENDING UP CLOSE TO 30F AS ADVERTISED ON WARM NOSE RIGHT AHEAD OF COLD FRONT. TEMPERATURES THEN FALL INTO THE SINGLE DIGITS SATURDAY MORNING AND THEN LEVEL OFF NEAR THOSE LEVELS IN STRONG COLD ADVECTION REGIME. WIND CHILLS DROP INTO THE 10 TO 20 BELOW ZERO RANGE...SO CERTAINLY MAY HAVE SOME MARGINAL ADVISORY CONDITIONS BUT SEEMS LIKE WE CAN ESCAPE WITHOUT HEADLINES FOR NOW. && .AVIATION/06Z TAFS/... LIGHT SNOW AND BLOWING SNOW CONTINUES TO REDUCE VISIBILITIES INTO THE IFR RANGE WHILE CEILINGS HAVE BEEN HOLDING UP IN MVFR AREA. BULK OF SNOW SHOULD TAPER OFF SHORTLY AFTER MIDNIGHT WITH LINGERING SNOW SHOWERS ALONG AND BEHIND THE COLD FRONT. STRONGEST WINDS ARE OVER BUT GUSTS OF 25 TO 30 KNOTS STILL EXPECTED INTO SATURDAY AS WINDS TURN TO WEST AND THEN NORTHWEST. && .MARINE... LET THE GALE EXPIRE AT 9PM AND CONVERTED TO A SMALL CRAFT ADVISORY THAT RUNS ANOTHE 24 HOURS TO SATURDAY EVENING AT 9PM. STILL GUSTING AROUND 30 KNOTS AHEAD OF THE COLD FRONT BUT GRADUALLY WINDING DOWN AS EXPECTED AS GRADIENT RELAXES. WINDS TURN NORTHWEST BEHIND THE FRONT SATURDAY AND WILL BE GUSTING INTO THE 25 TO 30 KNOT RANGE. && .PREV DISCUSSION... /ISSUED 310 PM CST FRI JAN 24 2014/ TONIGHT - CONFIDENCE...HIGH. THERE IS A BREAK IN THE SNOW THIS AFTERNOON. TEMPS WILL BE STEADILY RISING INTO THE UPPER 20S/AROUND 30 UNTIL AROUND MIDNIGHT. SOME MODELS SUGGEST TEMPS COULD SPIKE UP INTO THE LOWER/MID 30S JUST AHEAD OF THE SURFACE TROUGH AND COLD FRONT. GUSTY SOUTHWEST WINDS WILL GRADUALLY DIMINISH THROUGH THE EVENING. REDUCED VISIBILITIES DUE TO BLOWING SNOW WILL BECOME LESS WIDESPREAD... BUT FALLING SNOW WITH MODERATE WINDS COULD LEAD TO LOWER VISIBILITY THROUGH THE LATE EVENING. THUS...NO CHANGE TO WINTER WEATHER ADVISORY HEADLINE THAT EXPIRES AT MIDNIGHT. ANOTHER MID LEVEL SHORTWAVE WILL SWING DOWN THROUGH SOUTHERN WI FROM LATE AFTERNOON THROUGH LATE EVENING. CURRENT UPSTREAM OBSERVATIONS SUGGEST THIS WILL BE DELAYED INTO THE EVENING HOURS. FRONTOGENESIS AND WEAK OMEGA WILL LEAD TO SNOW ACCUMULATION OF AROUND AN INCH...MAYBE UP TO 2 IN A FEW SPOTS. WINDS WILL SHIFT TO THE WEST AND BECOME A LITTLE LIGHTER DURING THE SNOWFALL THIS EVENING AS THE SURFACE TROUGH MOVES THROUGH. THE MAIN COLD FRONT WILL HOLD OFF UNTIL AFTER MIDNIGHT...ON THE BACK EDGE OF THE SNOW. THERE COULD STILL BE A FEW FLURRIES THROUGH THE REST OF THE NIGHT...BUT PLAN ON WINDS INCREASING OUT OF THE NORTHWEST AND TEMPERATURES TO BE DROPPING. SATURDAY - CONFIDENCE...HIGH. DRY AIR WILL MOVE INTO SOUTHERN WI ON GUSTY NORTHWEST WINDS SATURDAY MORNING. THERE COULD BE A FEW FLURRIES LINGERING THROUGH THE MORNING HOURS IN SOUTHEAST WI DUE TO STEEP LOW LEVEL LAPSE RATES...BUT NO FURTHER ACCUMULATION. THE WINDS WILL DEFINITELY BLOW THE RECENT SNOW AROUND...SO PLAN ON REDUCED VISIBILITIES AND DRIFTING AT TIMES...ESPECIALLY IN RURAL AREAS. NO WINTER WEATHER ADVISORY PLANNED TO COVER THE BLOWING SNOW AT THIS TIME...WILL LIKELY JUST HANDLE IT WITH A SPECIAL WEATHER STATEMENT. THE NORTHWEST WINDS WILL USHER ARCTIC AIR INTO THE REGION. MAX TEMPS AROUND 10 DEGREES SATURDAY WILL OCCUR RIGHT AWAY IN THE MORNING...WITH STEADILY FALLING TEMPS INTO THE LOWER SINGLE DIGITS BY THE AFTERNOON. WIND CHILL VALUES WILL FALL INTO THE 10 TO 20 BELOW ZERO RANGE DURING THE AFTERNOON AS WELL. SATURDAY NIGHT THROUGH MONDAY - FORECAST CONFIDENCE...MEDIUM. SHORT TERM GUIDANCE IN GOOD AGREEMENT ON SHORT WAVE TROUGH ROTATING SOUTHEAST AROUND CENTRAL CANADA VORTEX SATURDAY NIGHT AND SUNDAY. PATH OF WAVE FROM THE EASTERN DAKOTAS SOUTHEAST THROUGH THE WI/IL BORDER AREA SUNDAY MORNING. INITIAL SURGE OF LOW TO MID LEVEL WARM AIR ADVECTION SERVES TO RAPIDLY MOISTEN THE AIR MASS AROUND/AFTER MIDNIGHT SUNDAY NIGHT. DESPITE GFS TRENDING MORE TOWARD THE SOUTHWEST WITH SFC LOW PRESSURE...SYNOPTIC SCALE FORCING REMAINS FARTHER NORTH. BOTH NAM AND GFS SHOW LAYER Q-VECTOR CONVERGENCE REACHING 30 UNITS AFFECTING SOUTHERN WI AROUND 12Z/26. ENOUGH CONFIDENCE TO KEEP HIGH POPS GOING LATE SAT NIGHT...CARRYING OVER INTO SUN MRNG. SECONDARY SPOKE OF LAYER VORTICITY ROTATES AROUND POLAR LOW LATER SUNDAY. WHILE STRONGEST SYNOPTIC SCALE FORCING WITH THIS SECOND SYSTEM REMAINS NORTH...IT DOES CONTRIBUTE TO ARCTIC COLD FRONT SLIDING SOUTH ACROSS SOUTHERN WI SUN AFTN AND EVE. 85H TEMPS TUMBLE TO AROUND -25 BY 12Z/MONDAY WITH THE COLD AIR REMAINING IN PLACE THROUGH TUESDAY. THE COLDEST AIR WILL REMAIN OVER THE AREA MONDAY INTO TUESDAY NIGHT BEFORE SLIGHTLY MODIFYING. LITTLE TEMPERATURE RECOVERY IS EXPECTED ON MONDAY WITH HIGH TEMPERATURES REMAINING BELOW ZERO. WILL HOLD OFF ON ANY ADDITIONAL WINTER WEATHER HEADLINES FOR NOW. WINTER WX ADVY MAY BE ISSUED FOR FALLING SNOW TRANSITIONING TO BLOWING SNOW THREAT ON SUNDAY...WITH WIND CHILL ADVISORY TO BE NEEDED SUNDAY NIGHT INTO MONDAY. WIND CHILL WATCH FOR MONDAY NIGHT INTO TUESDAY MAY BE ISSUED IN LATER SHIFTS...HOWEVER WL GET CLOSE TO WIND CHILL WARNING CRITERIA IN WESTERN AREAS BRIEFLY MON MRNG. AT THIS POINT...MONDAY NIGHT/TUESDAY MORNING LOOKS TO BE THE COLDEST PERIOD WITH LOWEST WIND CHILLS. MONDAY NIGHT THROUGH FRIDAY - FORECAST CONFIDENCE...HIGH INITIALLY TRENDING TO LOW ON THU/FRI. THE BITTERLY COLD AIR WILL REMAIN IN PLACE FOR THE FIRST PORTION OF THE PERIOD AS SLUG OF 85H AIR WITH TEMPS BTWN 18 AND 22 BELOW ZERO LINGERS. 85H STANDARDIZED ANOMOLIES ONCE AGAIN FALL BELOW 3 FOR TEMPS EARLY NEXT WEEK. EXPECT SLIGHT MODERATION IN TEMPERATURES BEGINNING LATER TUESDAY CONTINUING AT LEAST THROUGH WEDNESDAY AS UPPER LEVEL FLOW BACKS TO THE NORTHWEST AHEAD OF NEXT SHORT WAVE/CLIPPERY TYPE SYSTEM EXPECTED AROUND THU PERIOD. ECMWF MOST AGGRESSIVE WITH SHORT WAVE AND LOW PRESSURE MOVING ACROSS WESTERN GTLAKES WED NGT AND THU...CARRYING VIGOROUS COLD FRONT ACROSS SRN WI EARLY THU. 12Z GFS HAS NOW SWITCHED TO A SIMILAR SOLUTION...WITH CLIPPER AFFECTING WI ON THU. ECMWF HAS BEEN SHOWING FAIR RUN TO RUN CONSISTENCY WITH THIS FEATURE AND WILL CONTINUE WITH SMALL CHANCE FOR -SN ON THURSDAY AS COLD FRONT SLIPS THROUGH REGION. SRN WI RECEIVES ONLY A GLANCING BLOW FROM CORE OF COLD AIR LATER THU INTO THU NIGHT WITH SLIGHTLY WARMER BUT STILL BELOW NORMAL TEMPS RETURNING FOR FRI. GFS 5 DAY ANOMOLIES CENTERED 00Z/29 SHOWS LARGE NEGATIVE ANOMOLY OF 200M ASSOCIATED WITH POLAR VORTEX OVER SOUTHERN CANADA INTO THE GREAT LAKES...BUT DOES WEAKEN A BIT BY 00Z/01 AS UPPER LEVEL FLOW BECOMES A BIT MORE WEST TO NORTHWEST. APPEARS WELL BELOW NORMAL TEMPERATURES WILL CONTINUE TO FINISH OFF THE MONTH. AVIATION/00Z TAFS/...STRONG AND GUSTY SWLY WINDS WILL GRADUALLY DIMINISH LATE THIS AFTERNOON AND EVENING. SNOW WILL SPREAD FROM WEST TO EAST THIS EVENING. MID TO HIGH CLOUDS WILL LOWER TO 1.0-3.0 KFT BY EARLY EVENING WITH SNOW DEVELOPING. CURRENT OBSERVATIONS SUGGEST THE SNOW ARRIVAL INTO SOUTH CENTRAL WI WILL BE DELAYED A COUPLE OF HOURS. VSBYS WITH THE SNOW EXPECTED FALL TO AROUND 1 MILE. THE PASSAGE OF AN ARCTIC FRONT WILL BRING GUSTY NORTHWEST WINDS AND BEGIN TO DRY OUT THE ATMOSPHERE LATE TONIGHT. THUS THE SNOW SHOULD END BY 09Z FOR KMSN AND BETWEEN 09Z AND 12Z OVER THE SE WI TAF SITES. THE LOW CLOUDS WILL SCATTER OUT DURING THIS PERIOD BUT BLOWING SNOW MAY STILL LIMIT VSBYS THROUGH THE DAY SATURDAY. MARINE...A GALE WARNING IS IN EFFECT INTO THIS EVENING. AN ARCTIC FRONT WILL THEN PASS THROUGH LATE TONIGHT WITH BRISK NORTHWEST WINDS AFTERWARD. A SMALL CRAFT ADVISORY WILL BE NEEDED AFTER THE GALE WARNING EXPIRES. THERE COULD BE A FEW GUSTS TO 35 KNOTS SATURDAY MORNING...BUT IT LOOKS TOO MARGINAL TO CARRY A GALE AT THIS TIME. THE BRISK NWLY WINDS WILL DIMINISH SAT EVENING. THERE IS A LARGE ICE COVER OVER THE NEARSHORE WATERS BUT HIGH WAVES AND HEAVY FREEZING SPRAY ARE EXPECTED TOWARD OPEN WATERS WHERE MUCH LESS ICE EXISTS. && .MKX WATCHES/WARNINGS/ADVISORIES... WI...WINTER WEATHER ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR WIZ046- 047-051-052-056>060-062>072. LM...SMALL CRAFT ADVISORY UNTIL 9 PM CST SATURDAY FOR LMZ643>646. && $$ UPDATE...CRAVEN TONIGHT/SATURDAY AND AVIATION/MARINE...MRC SATURDAY NIGHT THROUGH FRIDAY...MBK
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
841 PM CST FRI JAN 24 2014 .UPDATE... ISSUED AT 840 PM CST FRI JAN 24 2014 THE MAIN SNOW BAND IS MOVING THROUGH THE AREA WITH REPORTS COMING IN OF AROUND 1 TO 1.5 INCHES. WITH SURFACE TEMPERATURES AROUND THE FREEZING MARK...THE LIQUID TO SNOW EQUIVALENT RATIO IS LOWER THAN WHAT IT HAS BEEN FOR MANY OF OUR SNOWS THIS WINTER AT AROUND 11 TO 1. THE FIRST WAVE OF SNOW WILL COME TO AN END OVER THE NEXT FEW HOURS AS THE REGION SITS IN THE WARM SECTOR OF AN OCCLUDED LOW PRESSURE SYSTEM. WITH WARMER AIR SITTING OVER NORTHERN IOWA AND SOUTHERN MINNESOTA...THE COLUMN HAS LOST ICE AND FREEZING DRIZZLE IS OCCURRING. THIS WILL LEAD TO SOME ICY ROAD CONDITIONS IN AREAS THAT ROADS HAVE NOT BEEN TREATED. WHILE WINDS ARE PICKING UP OUT OF THE NORTHWEST IN THIS WARM SECTOR ACROSS CENTRAL MINNESOTA...THERE HAS NOT BEEN MANY OBSERVATIONS IN THIS AREA SHOWING ANY LOW VISIBILITIES FROM BLOWING SNOW. THIS IS LIKELY DUE TO THE DRIZZLE THAT IS OCCURRING AND SINCE THIS WAS A HIGHER LIQUID CONTENT SNOWFALL. THE NEXT CONCERN COMES OVERNIGHT AS THE MAIN COLD FRONT...WHICH CURRENTLY EXTENDS FROM DULUTH WEST TOWARD FARGO...PUSHES THROUGH AND BRINGS A SECOND ROUND OF SNOW SHOWERS AND MUCH STRONGER WINDS WITH IT. RADAR/OBS ALONG THIS FRONT SHOW SOME CONVECTIVE LOOKING SNOW SHOWERS THAT ALONG WITH THE STRONGER WINDS COULD CAUSE SOME BRIEF VISIBILITY DROPS DOWN TO LESS THAN A MILE. 25.00Z RAP FORECAST SOUNDINGS ARE SHOWING SOME GUSTS IN THE 35 TO 45 MPH RANGE FOR A FEW HOUR PERIOD WHEN FROPA OCCURS. THIS MATCHES WHAT IS OCCURRING UPSTREAM NEAR DULUTH WHERE SOME OBS HAVE BEEN IN THAT RANGE ALONG THE FRONT. CONDITIONS THEN SHOULD IMPROVE TOWARD DAYBREAK AS THE WINDS DROP DOWN AND SKIES CLEAR OUT AS COLD AIR MOVES BACK IN. && .SHORT TERM...(THIS EVENING THROUGH SATURDAY) ISSUED AT 325 PM CST FRI JAN 24 2014 STRONG WINTER STORM TO IMPACT THE AREA SUNDAY INTO SUNDAY NIGHT WITH NEAR BLIZZARD CONDITIONS POSSIBLE WEST OF THE MISSISSIPPI RIVER. DANGEROUS...POTENTIALLY LIFE THREATENING...WIND CHILLS OF -35 TO -45 EXPECTED ACROSS THE ENTIRE AREA FROM LATE SUNDAY NIGHT THROUGH TUESDAY MORNING. A COLD FRONT WILL PUSH THROUGH THE REGION LATE THIS AFTERNOON THOUGH THIS EVENING BRINING LIGHT SNOW TO THE AREA. SNOW ACCUMULATIONS OF AROUND AN INCH ARE EXPECTED WITH A FEW 1.5 INCH ACCUMULATIONS POSSIBLE. NORTHWEST WINDS WILL INCREASE TO 20 TO 30 MPH WITH GUSTS TO AROUND 40 MPH POSSIBLE IN THE OPEN AREAS OF SOUTHEAST MINNESOTA AND NORTHEAST IOWA. THESE GUSTY NORTHWEST WINDS WILL PRODUCE AREAS OF DRIFTING AND POSSIBLY BLOWING SNOW THAT COULD PRODUCE A FEW SLICK STRETCHES ON AREA ROADS TONIGHT INTO EARLY SATURDAY MORNING. WILL HAVE TO MONITOR THIS CLOSELY THIS EVENING. BREEZY NORTHWEST WINDS WILL BRING AREAS OF BLOWING SNOW TO THE OPEN AREAS OF SOUTHEAST MINNESOTA AND NORTHEAST IOWA EARLY SATURDAY MORNING WITH PATCHY BLOWING SNOW ELSEWHERE. HIGH PRESSURE THEN MOVES OVER THE UPPER MISSISSIPPI RIVER VALLEY FOR A BRIEF BREAK IN THE ACTION SATURDAY AFTERNOON BEFORE A POTENT SYSTEM TAKES AIM ON THE REGION SATURDAY NIGHT INTO SUNDAY. .LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY) ISSUED AT 325 PM CST FRI JAN 24 2014 A STRONG BAROCLINIC ZONE WILL BE IN PLACE OVER THE UPPER MISSISSIPPI RIVE VALLEY SATURDAY NIGHT INTO SUNDAY AS A SHORTWAVE DROPS SOUTH OUT OF THE NORTHERN PLAINS. SURFACE LOW PRESSURE WILL RIDE ALONG THIS ZONE OUT OF NORTH DAKOTA EARLY SATURDAY NIGHT...PUSHING SOUTHEAST INTO THE FORECAST AREA LATE SATURDAY NIGHT INTO SUNDAY MORNING. SNOW WILL OVERSPREAD SOUTHEAST MINNESOTA AND NORTHEAST IOWA MAINLY AFTER MIDNIGHT...THEN PUSHING INTO WESTERN WISCONSIN EARLY SATURDAY MORNING. FLUFFY SNOW ACCUMULATIONS OF 2 TO 4 INCHES ARE EXPECTED WITH THIS SYSTEM AND A WINTER WEATHER ADVISORY WILL LIKELY BE NEEDED. DANGEROUS CONDITIONS DEVELOP SUNDAY AFTERNOON AS A STRONG ARCTIC COLD FRONT RACES ACROSS THE AREA BRINGING NEAR BLIZZARD CONDITIONS TO SOUTHEAST MINNESOTA...NORTHEAST IOWA...AND POSSIBLY FAR SOUTHWEST WISCONSIN. NORTHWEST WINDS WILL INCREASE TO 25 TO 35 MPH WITH GUSTS AROUND 50 MPH POSSIBLE OVER THESE AREAS. THESE WINDS COMBINED WITH THE FLUFFY 2 TO 4 INCHES OF FRESHLY FALLEN SNOW WILL LEAD TO WHITEOUT CONDITIONS AT TIMES ALONG WITH DRIFTING SNOW. LOCATIONS ALONG AND EAST OF THE MISSISSIPPI RIVER WILL ALSO EXPERIENCE AREAS OF BLOWING SNOW AND POSSIBLY HAZARDOUS TRAVEL CONDITIONS AT TIMES. A WINTER STORM WARNING WILL LIKELY BE NEEDED OVER PORTIONS OF SOUTHEAST MINNESOTA AND NORTHEAST IOWA SUNDAY INTO SUNDAY NIGHT. WILL BE ISSUING A WINTER STORM WATCH WITH THIS PACKAGE. A WINTER WEATHER ADVISORY LOOKS LIKELY FOR AREAS ALONG AND EAST OF THE MISSISSIPPI RIVER FROM SUNDAY INTO SUNDAY NIGHT. DANGEROUSLY COLD WIND CHILLS THEN SURGE INTO THE AREA LATE SUNDAY NIGHT INTO MONDAY MORNING WHEN WIND CHILL VALUES WILL FALL TO -30 TO -45. THE COMBINATION OF THESE DANGEROUSLY COLD WIND CHILLS AND NEAR BLIZZARD CONDITIONS OVER WIND PRONE AREAS COULD CREATE A LIFE THREATENING SITUATION IF YOU WERE TO BECOME STRANDED OUTDOORS. DANGEROUSLY COLD WIND CHILLS ARE EXPECTED ACROSS THE ENTIRE FORECAST AREA FROM MIDNIGHT SUNDAY NIGHT ALL THE WAY THROUGH TUESDAY MORNING AND A WIND CHILL WARNING WILL BE NEEDED DURING THIS TIMEFRAME WHEN THE WIND CHILLS DROP TO 35 DEGREES BELOW ZERO OR LOWER. HIGH TEMPERATURES COULD BE AT RECORD LOW VALUES ON MONDAY WITH HIGHS ONLY IN THE SINGLE DIGITS TO TEENS BELOW ZERO. SEE CLIMATE SECTION BELOW FOR MORE INFORMATION. DANGEROUSLY COLD CONDITIONS CONTINUE MONDAY NIGHT WITH LOWS FALLING INTO THE -20 TO -25 RANGE. WIND CHILL VALUES OF -35 TO -45 ARE EXPECTED THROUGH THE NIGHT INTO TUESDAY MORNING. THE ARCTIC AIRMASS MAINTAINS ITS GRIP ON THE REGION ON TUESDAY WITH HIGHS ONLY IN THE SINGLE DIGITS BELOW ZERO. ANOTHER BITTERLY COLD NIGHT IS IN STORE FOR THE REGION TUESDAY NIGHT WITH LOWS IN THE TEENS BELOW ZERO. A WIND CHILL ADVISORY WILL BE NEEDED FROM TUESDAY AFTERNOON THROUGH WEDNESDAY MORNING. HIGH TEMPERATURES LOOK TO WARM INTO TEENS THURSDAY INTO FRIDAY AS WESTERLY FLOW SETS UP OVER THE REGION. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING) ISSUED AT 533 PM CST FRI JAN 24 2014 SNOW HAS ALREADY MOVED INTO RST AND WILL REACH LSE SHORTLY AS AN INITIAL COLD FRONT APPROACHES THE REGION. THIS LOOKS LIKE IT WILL BE ABOUT A 3 HOUR SNOW WITH VISIBILITIES DROPPING DOWN TO A HALF MILE AT ITS WORSE PERIOD. BY 3Z...THE SNOW SHOULD BE OUT OF BOTH SITES THOUGH WINDS WILL BE PICKING UP OUT OF THE NORTHWEST AS THE FIRST COLD FRONT PASSES THROUGH. THIS WILL LIKELY LEAD TO SOME BLOWING SNOW WHICH WILL CAUSE VISIBILITIES TO DROP TO 3SM OR POSSIBLY LOWER. CEILINGS WILL REMAIN MVFR UNTIL THE SECOND COLD FRONT COMES THROUGH LATER TONIGHT AND BRINGS DRIER AND COLDER AIR IN WITH IT. THE STRONGEST WIND GUSTS WILL COME AFTER THIS FRONT COMES THROUGH WITH SOME 30 TO 40KT GUSTS EXPECTED. CONDITIONS WILL GRADUALLY IMPROVE THROUGH THE DAY TOMORROW AS A RIDGE OF HIGH PRESSURE SLOWLY MOVES IN FROM THE WEST. && .CLIMATE...MONDAY ISSUED AT 325 PM CST FRI JAN 24 2014 WITH FORECAST HIGH TEMPERATURES RUNNING BETWEEN -5 AND -15 ON MONDAY...SEVERAL RECORD COLD HIGH TEMPERATURES MAY BE SET OR TIED. MANY OF THESE RECORDS WERE SET IN EITHER 1902 OR 1972. BELOW ARE THE RECORD COLD HIGH TEMPERATURES FOR THAT DAY. AUSTIN MN -2 IN 1950 CHARLES CITY IA -5 IN 1904 DECORAH IA -4 IN 1902 LA CROSSE WI -4 IN 1902 MEDFORD WI -8 IN 1902 NEILLSVILLE WI -10 IN 1902 PRAIRIE DU CHIEN WI -1 IN 1904 RICHLAND CENTER WI 2 IN 1972 ROCHESTER MN -5 IN 1966 SPARTA WI -1 IN 1972 THEILMAN MN -8 IN 1972 WINONA MN -9 IN 1972 && .ARX WATCHES/WARNINGS/ADVISORIES... WI...WINTER STORM WATCH FROM SUNDAY MORNING THROUGH SUNDAY EVENING FOR WIZ061. MN...WINTER STORM WATCH FROM SUNDAY MORNING THROUGH SUNDAY EVENING FOR MNZ086-087-094-095. IA...WINTER STORM WATCH FROM SUNDAY MORNING THROUGH SUNDAY EVENING FOR IAZ008>011-018-019-029-030. && $$ UPDATE...HALBACH SHORT TERM...WETENKAMP LONG TERM...WETENKAMP AVIATION...HALBACH CLIMATE...BOYNE
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
325 PM CST FRI JAN 24 2014 .SHORT TERM...(THIS EVENING THROUGH SATURDAY) ISSUED AT 325 PM CST FRI JAN 24 2014 STRONG WINTER STORM TO IMPACT THE AREA SUNDAY INTO SUNDAY NIGHT WITH NEAR BLIZZARD CONDITIONS POSSIBLE WEST OF THE MISSISSIPPI RIVER. DANGEROUS...POTENTIALLY LIFE THREATENING...WIND CHILLS OF -35 TO -45 EXPECTED ACROSS THE ENTIRE AREA FROM LATE SUNDAY NIGHT THROUGH TUESDAY MORNING. A COLD FRONT WILL PUSH THROUGH THE REGION LATE THIS AFTERNOON THOUGH THIS EVENING BRINING LIGHT SNOW TO THE AREA. SNOW ACCUMULATIONS OF AROUND AN INCH ARE EXPECTED WITH A FEW 1.5 INCH ACCUMULATIONS POSSIBLE. NORTHWEST WINDS WILL INCREASE TO 20 TO 30 MPH WITH GUSTS TO AROUND 40 MPH POSSIBLE IN THE OPEN AREAS OF SOUTHEAST MINNESOTA AND NORTHEAST IOWA. THESE GUSTY NORTHWEST WINDS WILL PRODUCE AREAS OF DRIFTING AND POSSIBLY BLOWING SNOW THAT COULD PRODUCE A FEW SLICK STRETCHES ON AREA ROADS TONIGHT INTO EARLY SATURDAY MORNING. WILL HAVE TO MONITOR THIS CLOSELY THIS EVENING. BREEZY NORTHWEST WINDS WILL BRING AREAS OF BLOWING SNOW TO THE OPEN AREAS OF SOUTHEAST MINNESOTA AND NORTHEAST IOWA EARLY SATURDAY MORNING WITH PATCHY BLOWING SNOW ELSEWHERE. HIGH PRESSURE THEN MOVES OVER THE UPPER MISSISSIPPI RIVER VALLEY FOR A BRIEF BREAK IN THE ACTION SATURDAY AFTERNOON BEFORE A POTENT SYSTEM TAKES AIM ON THE REGION SATURDAY NIGHT INTO SUNDAY. .LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY) ISSUED AT 325 PM CST FRI JAN 24 2014 A STRONG BAROCLINIC ZONE WILL BE IN PLACE OVER THE UPPER MISSISSIPPI RIVE VALLEY SATURDAY NIGHT INTO SUNDAY AS A SHORTWAVE DROPS SOUTH OUT OF THE NORTHERN PLAINS. SURFACE LOW PRESSURE WILL RIDE ALONG THIS ZONE OUT OF NORTH DAKOTA EARLY SATURDAY NIGHT...PUSHING SOUTHEAST INTO THE FORECAST AREA LATE SATURDAY NIGHT INTO SUNDAY MORNING. SNOW WILL OVERSPREAD SOUTHEAST MINNESOTA AND NORTHEAST IOWA MAINLY AFTER MIDNIGHT...THEN PUSHING INTO WESTERN WISCONSIN EARLY SATURDAY MORNING. FLUFFY SNOW ACCUMULATIONS OF 2 TO 4 INCHES ARE EXPECTED WITH THIS SYSTEM AND A WINTER WEATHER ADVISORY WILL LIKELY BE NEEDED. DANGEROUS CONDITIONS DEVELOP SUNDAY AFTERNOON AS A STRONG ARCTIC COLD FRONT RACES ACROSS THE AREA BRINGING NEAR BLIZZARD CONDITIONS TO SOUTHEAST MINNESOTA...NORTHEAST IOWA...AND POSSIBLY FAR SOUTHWEST WISCONSIN. NORTHWEST WINDS WILL INCREASE TO 25 TO 35 MPH WITH GUSTS AROUND 50 MPH POSSIBLE OVER THESE AREAS. THESE WINDS COMBINED WITH THE FLUFFY 2 TO 4 INCHES OF FRESHLY FALLEN SNOW WILL LEAD TO WHITEOUT CONDITIONS AT TIMES ALONG WITH DRIFTING SNOW. LOCATIONS ALONG AND EAST OF THE MISSISSIPPI RIVER WILL ALSO EXPERIENCE AREAS OF BLOWING SNOW AND POSSIBLY HAZARDOUS TRAVEL CONDITIONS AT TIMES. A WINTER STORM WARNING WILL LIKELY BE NEEDED OVER PORTIONS OF SOUTHEAST MINNESOTA AND NORTHEAST IOWA SUNDAY INTO SUNDAY NIGHT. WILL BE ISSUING A WINTER STORM WATCH WITH THIS PACKAGE. A WINTER WEATHER ADVISORY LOOKS LIKELY FOR AREAS ALONG AND EAST OF THE MISSISSIPPI RIVER FROM SUNDAY INTO SUNDAY NIGHT. DANGEROUSLY COLD WIND CHILLS THEN SURGE INTO THE AREA LATE SUNDAY NIGHT INTO MONDAY MORNING WHEN WIND CHILL VALUES WILL FALL TO -30 TO -45. THE COMBINATION OF THESE DANGEROUSLY COLD WIND CHILLS AND NEAR BLIZZARD CONDITIONS OVER WIND PRONE AREAS COULD CREATE A LIFE THREATENING SITUATION IF YOU WERE TO BECOME STRANDED OUTDOORS. DANGEROUSLY COLD WIND CHILLS ARE EXPECTED ACROSS THE ENTIRE FORECAST AREA FROM MIDNIGHT SUNDAY NIGHT ALL THE WAY THROUGH TUESDAY MORNING AND A WIND CHILL WARNING WILL BE NEEDED DURING THIS TIMEFRAME WHEN HIGH TEMPERATURES COULD BE AT RECORD LOW VALUES ON MONDAY WITH HIGHS ONLY IN THE SINGLE DIGITS TO TEENS BELOW ZERO. SEE CLIMATE SECTION BELOW FOR MORE INFORMATION. DANGEROUSLY COLD CONDITIONS CONTINUE MONDAY NIGHT WITH LOWS FALLING INTO THE -20 TO -25 RANGE. WIND CHILL VALUES OF -35 TO -45 ARE EXPECTED THROUGH THE NIGHT INTO TUESDAY MORNING. THE ARCTIC AIRMASS MAINTAINS ITS GRIP ON THE REGION ON TUESDAY WITH HIGHS ONLY IN THE SINGLE DIGITS BELOW ZERO. ANOTHER BITTERLY COLD NIGHT IS IN STORE FOR THE REGION TUESDAY NIGHT WITH LOWS IN THE TEENS BELOW ZERO. A WIND CHILL ADVISORY WILL BE NEEDED FROM TUESDAY AFTERNOON THROUGH WEDNESDAY MORNING. HIGH TEMPERATURES LOOK TO WARM INTO TEENS THURSDAY INTO FRIDAY AS WESTERLY FLOW SETS UP OVER THE REGION. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON) ISSUED AT 1110 AM CST FRI JAN 24 2014 SHORT WAVE TROUGH OVER SOUTHERN MANITOBA WILL MOVE RAPIDLY SOUTHEAST AND ACROSS THE AREA DURING THE EARLY EVENING HOURS. THIS WILL PUSH THE COLD FRONT THAT IS ALONG THE CANADIAN BORDER THROUGH THE REGION AS WELL AND IT WILL PRODUCE A 4 TO 5 HOUR BAND OF LIGHT SNOW AS IT COMES THROUGH. SOME MINOR DIFFERENCES ON THE TIMING OF THE SNOW WITH THE 24.14Z HRRR SHOWING IT STARTING AT BOTH TAF SITES AROUND 22Z WHILE THE 24.12Z NAM DOES NOT BRING IT IN UNTIL 00Z. PREVIOUS FORECAST SPLIT THE DIFFERENCE BETWEEN THESE TWO MODELS AND HAVE STAYED WITH THAT TIMING OF 23Z. EXPECT TO SEE THE VISIBILITY GO DOWN TO IFR IN THE SNOW WITH MVFR CEILINGS. ONCE THE SNOW ENDS AND THE COLD FRONT MOVES THROUGH...THE WINDS WILL COME AROUND TO THE NORTHWEST AND INCREASE ENOUGH TO PRODUCE BLOWING SNOW AT KRST WITH MVFR VISIBILITY EXPECTED. THE CLOUDS WILL CLEAR OUT OVERNIGHT BUT THE WINDS ARE NOT EXPECTED TO SETTLE DOWN ENOUGH FOR THE BLOWING SNOW TO END AT KRST UNTIL SATURDAY MORNING. && .CLIMATE...MONDAY ISSUED AT 325 PM CST FRI JAN 24 2014 WITH FORECAST HIGH TEMPERATURES RUNNING BETWEEN -5 AND -15 ON MONDAY...SEVERAL RECORD COLD HIGH TEMPERATURES MAY BE SET OR TIED. MANY OF THESE RECORDS WERE SET IN EITHER 1902 OR 1972. BELOW ARE THE RECORD COLD HIGH TEMPERATURES FOR THAT DAY. AUSTIN MN -2 IN 1950 CHARLES CITY IA -5 IN 1904 DECORAH IA -4 IN 1902 LA CROSSE WI -4 IN 1902 MEDFORD WI -8 IN 1902 NEILLSVILLE WI -10 IN 1902 PRAIRIE DU CHIEN WI -1 IN 1904 RICHLAND CENTER WI 2 IN 1972 ROCHESTER MN -5 IN 1966 SPARTA WI -1 IN 1972 THEILMAN MN -8 IN 1972 WINONA MN -9 IN 1972 && .ARX WATCHES/WARNINGS/ADVISORIES... WI...WINTER STORM WATCH FROM SUNDAY MORNING THROUGH SUNDAY EVENING FOR WIZ061. MN...WINTER STORM WATCH FROM SUNDAY MORNING THROUGH SUNDAY EVENING FOR MNZ086-087-094-095. IA...WINTER STORM WATCH FROM SUNDAY MORNING THROUGH SUNDAY EVENING FOR IAZ008>011-018-019-029-030. && $$ SHORT TERM...WETENKAMP LONG TERM...WETENKAMP AVIATION...04 CLIMATE...BOYNE
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1110 AM CST FRI JAN 24 2014 .SHORT TERM...(TODAY THROUGH TONIGHT) ISSUED AT 315 AM CST FRI JAN 24 2014 AN UPPER LEVEL SHORTWAVE TROUGH WAS PUSHING INTO NORTHWEST WI EARLY THIS MORNING...PER LATEST WATERVAPOR IMAGERY. SOME LIGHT SNOW WAS RESULTING...MOSTLY CONFINED TO NORTHERN PARTS OF THE REGION. THIS FEATURE WILL BRING SOME LIGHT SNOW TO THE FORECAST AREA...WITH THE BETTER CHANCES/MINOR ACCUMULATIONS MOSTLY FROM THE I-94 CORRIDOR NORTHWARD. ANOTHER UPPER LEVEL SHORTWAVE...A BIT STRONGER...DROPS IN TONIGHT...BRINGING A BETTER CHANCE FOR WIDESPREAD SNOW. OVERALL...1 TO 2 INCHES LOOKS LIKELY FOR TODAY INTO TONIGHT...WITH MOST ACCUMULATIONS COMING THIS EVENING. BLUSTERY WINDS COULD LEAD TO PATCHY BLOWING/DRIFTING SNOW IN THE WIND PRONE AREAS. .LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY) ISSUED AT 315 AM CST FRI JAN 24 2014 SIGNIFICANT STORM SYSTEM TO BRING A VARIETY OF WINTER WEATHER...SOME DANGEROUS TO POTENTIALLY DEADLY...SUNDAY INTO THE EARLY PART OF THE NEW WORK WEEK. THIS WILL HAVE IMPACTS ON TRAVEL AND OUTDOOR ACTIVITIES. HEADLINES WILL BE NEEDED FOR THIS STORM...WATCHES...WARNINGS AND/OR ADVISORIES. PART 1 NAM/GFS/ECMWF ALL IN GOOD AGREEMENT WITH DRIVING AN UPPER LEVEL TROUGH ACROSS THE UPPER MISSISSIPPI RIVER VALLEY SAT NIGHT/SUN...WITH A PIECE OF ENERGY LEADING IT IN. STRONG ISENTROPIC UPGLIDE ON THE 280-295 K SFCS BETWEEN 06-15Z SUN...WITH LOW LEVEL WARM AIR ADVECTION IN THE 925-700 MB LAYER BULLS-EYEING THE AREA AT 12Z. HEFTY THERMODYNAMICS...BUT QUICK MOVING. THE STORM/S SFC WARM FRONT MOVES IN FIRST...ACROSS THE AREA DURING THE EARLY MORNING HOURS OF SUN...WITH A SLOPING FRONTOGENETIC RESPONSE INDICATED VIA SOUTHWEST-NORTHEAST RUNNING X-SECTIONS. THE SYSTEM/S COLD FRONT MOVES THROUGH IN THE AFTERNOON/EVENING AS THE SFC LOW DEPARTS EAST INTO MICH. SOME LIGHT SNOW EXPECTED WITH THIS...BUT THE BULK OF THE ACCUMULATIONS SHOULD COME WITH THE LOW LEVEL THERMODYNAMICS/QG CONVERGENCE FROM 850-500 MB/AND THE LEADING PIECE OF UPPER LEVEL ENERGY. THE SNOW WILL MOVE IN BY LATE SAT EVENING/OVERNIGHT...WITH THE MAIN SNOW BAND SHIFTING EAST BY THE AFTERNOON. WHILE SNOW IS EXPECTED TO BE THE MAIN PCPN TYPE...SOUNDINGS AND X- SECTIONS SUGGEST THAT A WINTRY MIX WILL ALSO BE POSSIBLE IN THE SOUTHWEST. THE NAM IS MORE AGGRESSIVE WITH THIS POTENTIALITY COMPARED TO THE GFS...WITH MORE WARMING AND A SHALLOWER CLOUD DEPTH ON THE WESTERN SIDE OF THIS SYSTEM. THIS SUGGESTS A LOSS OF ICE IN THE CLOUD AND POSSIBLY SOME MELTING...THUS BRINGING LIQUID/SLEET INTO THE PICTURE. THAT SAID...THE BULK OF THE PRECIPITATION THAT DOES FALL LOOKS TO BE COLD ENOUGH/ICE IN CLOUD THAT IT WOULD BE SNOW. STILL...ANOTHER ELEMENT TO WHAT IS GOING TO BE SOME VERY UNPLEASANT DAYS. AMOUNTS FROM 2 TO 4 INCHES LOOK REASONABLE...WITH THE QUICK NATURE OF THIS STORM HOLDING AMOUNTS DOWN. SOME ICING COULD ALSO RESULT...SHOULD FREEZING PCPN/SLEET BE REALIZED. PART 2 WINDS ARE GOING TO INCREASE SUN AFTERNOON...STAYING STRONG INTO THE NIGHT. THE NAM IS VERY STRONG WITH ITS WINDS...MIXING DOWN AS MUCH AS 47 KTS AT KRST DURING THE AFTERNOON. THE GFS IS ABOUT 10 KTS LESS. EITHER SOLUTION WILL RESULT IN BLOWING AND DRIFTING OF THE SNOW THAT FALLS EARLIER IN THE DAY. THE WIND PRONE AREAS OF SOUTHEAST MN AND NORTHEAST IA...ALONG WITH RIDGE-TOPS...COULD SEE NEAR BLIZZARD CONDITIONS AT TIMES...VSBYS 1/2 MILE OR LESS WITH LOTS OF BLOWING ACROSS ROADWAYS. PART 3 BRUTAL...POTENTIALLY DEADLY COLD MOVES IN FOR MON/TUE POST THIS SUNDAY STORM. ECMWF 850 MB TEMP ANOMALIES FALL TO -2.5 BY 12 MON...WITH -28C AT 850 MB DEPICTED IN THE GFS. HOW MUCH CLOUD COVER WILL BE AROUND IS A BIT UNCERTAIN AS THE REGION HOLDS UNDER THE CYCLONIC FLOW ALOFT...WHILE A SFC HIGH SLIDES ACROSS THE PLAINS. CLOUDS OBVIOUSLY ADD AN INSULATION FACTOR...WHILE CLEAR SKIES WOULD GIVE AN ADDITIONAL DROP IN OVERNIGHT TEMPS. AS IT LOOKS RIGHT NOW...LOWS IN THE -20S ARE PROBABLE TUE...WITH MINUS TEENS MON/WED. HIGHS AREN/T LIKELY TO CRACK ZERO UNTIL WED. IN FACT...THE WHOLE PERIOD FROM SUNDAY NIGHT THROUGH WED MORNING WILL BE SUB ZERO. ADD IN WINDS...AND WIND CHILLS -40 OR COLDER ARE LIKELY LATE SUN NIGHT/MON MORNING AND AGAIN LATE MON NIGHT/TUE MORNING. THIS COLD GOES FROM DANGEROUS TO DEADLY IF PRECAUTIONS ARE NOT TAKEN. WIND CHILL WARNINGS/ADVISORIES WILL BE NEEDED. SOMEWHAT QUIET FOR SNOW CHANCES FOR THE EARLY PART OF THE NEW WORK. SHORTWAVE ACTIVITY IS PROGGED TO MOVE NORTH OR WEST OF THE LOCAL AREA...WHICH SHOULD KEEP THE AREA DRY THROUGH WED. THE GFS AND ECMWF DISAGREE WITH HOW TO HANDLE A SHORTWAVE THAT BOTH SUGGEST WILL DROP ACROSS THE NORTHERN GREAT LAKES ON THU. THE GFS FAVORS KEEPING ITS INFLUENCE TO THE NORTH...WHILE THE EC RIDES ITS A BIT FARTHER SOUTH...WHICH WOULD RESULT IN SOME LIGHT SNOW CHANCES. DON/T HAVE A PREFERRED SOLUTION...SO WILL GO WITH CONSENSUS THIS GO AROUND. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON) ISSUED AT 1110 AM CST FRI JAN 24 2014 SHORT WAVE TROUGH OVER SOUTHERN MANITOBA WILL MOVE RAPIDLY SOUTHEAST AND ACROSS THE AREA DURING THE EARLY EVENING HOURS. THIS WILL PUSH THE COLD FRONT THAT IS ALONG THE CANADIAN BORDER THROUGH THE REGION AS WELL AND IT WILL PRODUCE A 4 TO 5 HOUR BAND OF LIGHT SNOW AS IT COMES THROUGH. SOME MINOR DIFFERENCES ON THE TIMING OF THE SNOW WITH THE 24.14Z HRRR SHOWING IT STARTING AT BOTH TAF SITES AROUND 22Z WHILE THE 24.12Z NAM DOES NOT BRING IT IN UNTIL 00Z. PREVIOUS FORECAST SPLIT THE DIFFERENCE BETWEEN THESE TWO MODELS AND HAVE STAYED WITH THAT TIMING OF 23Z. EXPECT TO SEE THE VISIBILITY GO DOWN TO IFR IN THE SNOW WITH MVFR CEILINGS. ONCE THE SNOW ENDS AND THE COLD FRONT MOVES THROUGH...THE WINDS WILL COME AROUND TO THE NORTHWEST AND INCREASE ENOUGH TO PRODUCE BLOWING SNOW AT KRST WITH MVFR VISIBILITY EXPECTED. THE CLOUDS WILL CLEAR OUT OVERNIGHT BUT THE WINDS ARE NOT EXPECTED TO SETTLE DOWN ENOUGH FOR THE BLOWING SNOW TO END AT KRST UNTIL SATURDAY MORNING. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...RIECK LONG TERM....RIECK AVIATION...04
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1145 PM EST SAT JAN 25 2014 .UPDATE... THE AVIATION SECTION HAS BEEN UPDATED BELOW. && .SYNOPSIS... ISSUED AT 326 PM EST SAT JAN 25 2014 A WARM FRONT WILL SLIDE EAST ACROSS CENTRAL INDIANA ON SUNDAY WHICH WILL RESULT IN SNOW ACCUMULATION WITH THE HIGHEST AMOUNTS NEAR AND NORTH OF INTERSTATE 74 SOUTHEAST OF INDIANAPOLIS AND NEAR AND NORTH OF INTERSTATE 70 NORTHWEST OF INDIANAPOLIS. THE BLOWING SNOW WILL SUBSIDE OVERNIGHT ONLY TO RETURN ON SUNDAY AND SUNDAY NIGHT. THE BITTER COLD WILL ALSO RETURN BEHIND AN ARCTIC FRONT OVERNIGHT SUNDAY NIGHT THROUGH WEDNESDAY. DRY WEATHER IS EXPECTED THE FIRST HALF OF NEXT WEEK UNDER THE INFLUENCE OF THE ARCTIC HIGH. THEN...SNOW CHANCES WILL RETURN BY THURSDAY NIGHT WITH TEMPERATURES WARMING TO NEAR NORMAL NEXT WEEKEND. && .NEAR TERM /TONIGHT THROUGH SUNDAY NIGHT/... ISSUED AT 1006 PM EST SAT JAN 25 2014 HIGH PRESSURE RIDGE HAS BROUGHT CLEAR SKIES AND FINALLY A BREAK FROM THE RELENTLESS WINDS EXPERIENCED THROUGHOUT THE DAY TODAY. TEMPS HAD TUMBLED QUICKLY IN THE ARCTIC AIRMASS THIS EVENING WITH TEMPS GENERALLY IN THE SINGLE DIGITS AND TEENS AS OF 03Z. ENDLESS STREAM OF CLIPPERS CONTINUE WITH THE NEXT ONE RAPIDLY DROPPING THROUGH THE DAKOTAS THIS EVENING. MID AND HIGH LEVEL CLOUDS AHEAD OF THIS SYSTEM WILL QUICKLY EXPAND BACK ACROSS THE REGION AFTER MIDNIGHT AS THE SURFACE WAVE APPROACHES. HAVE SOME CONCERN THAT DRIER AIR WITHIN THE BOUNDARY LAYER WILL LIMIT SNOWFALL A BIT AS THIS SYSTEM SWINGS INTO THE REGION EARLY SUNDAY. HAVE BACKED OFF ON ONSET OF LIGHT SNOW AND ACCUMS BETWEEN 09-12Z...AS MODEL SOUNDINGS HINT AT THE DRY LAYER WITHIN THE BOUNDARY LAYER NOT BEING ERODED COMPLETELY. WHILE DRIER AIR WILL LIMIT SNOWFALL INTENSITY... RATIOS WILL BE UP IN THE 15-18 TO 1 RANGE WHICH WILL COMPENSATE A BIT. 00Z NAM AND RAP HAVE BOTH COME IN FURTHER NORTH WITH THE MAIN SWATH OF SNOW LATE TONIGHT AND SUNDAY MORNING...AND EXPECT PRIOR TO DAYBREAK LIGHT SNOW WILL PRIMARILY BE CONFINED TO AREAS ALONG AND NORTH OF I-70. TEMPS SHOULD BOTTOM OUT AROUND 06-07Z BEFORE BEGINNING TO RISE IN RESPONSE TO CLOUDS AND EVAPORATIVE COOLING PROCESSES AS THE PRECIP ARRIVES. FORECAST LOWS LOOKED REASONABLE AND DID NOT CHANGE. PERTINENT PARTS OF THE AFTERNOON NEAR TERM DISCUSSION FOLLOWS. MODELS ARE IN GOOD AGREEMENT WITH THIS EVER EVOLVING AND HISTORIC JANUARY 2014 WINTER. A WARM FRONT WILL SLIDE EAST ACROSS THE AREA SUNDAY AS WILL A CLIPPER THAT WILL DROP SOUTHEAST IN THE FAST NORTHWEST FLOW. 285K ISENTROPIC ANALYSIS WAS SHOWING LOWERING CONDENSATION PRESSURE DEFICITS AFTER 09Z SPREADING FROM WEST TO EAST ALONG WITH STRONG ISENTROPIC LIFT THROUGH AROUND 15Z. MIXING RATIOS WERE FROM 2 TO 3 G/KG WHICH FOR A SOLID 12 HOUR SNOW WOULD NORMALLY PRODUCE AROUND 4 TO 6 INCHES OF SNOW. HOWEVER...WITH THE BEST LIFT AND DEEPEST MOISTURE ONLY EXPECTED TO LAST 6 HOURS...2 TO 3 INCHES LOOKS GOOD MAINLY NEAR AND NORTH OF INTERSTATE 74 TO THE SOUTHEAST OF INDIANAPOLIS AND NORTH OF INTERSTATE 70 TO THE NORTHWEST OF INDY. AMOUNTS WILL BE LESSER TO THE SOUTH WITH LESS THAN AN INCH SOUTHWEST. SOUTHWEST AREAS COULD ALSO SEE A MIX OF THE SNOW WITH RAIN WHICH COULD FURTHER REDUCE AMOUNTS. HOWEVER...WENT ON THE COLD SIDE OF MOS WITH THE SNOW PACK AND TRENDS AND DID NOT INCLUDE ANY MIX DOWN THERE AS OF YET. WILL GO WITH A WINTER WEATHER ADVISORY FOR SNOW AND BLOWING SNOW FROM 4 AM SUNDAY TO 7 AM MONDAY SINCE BLOWING SNOW WILL ALSO BE A FACTOR WITH WINDS GUSTING TO 30 MPH. WIND CHILLS WILL ONCE AGAIN FALL WELL BELOW ZERO OVERNIGHT SUNDAY NIGHT...ACROSS OUR NORTHWEST COUNTIES ESPECIALLY...AS THE ARCTIC FRONT SWEEPS THROUGH. WIND CHILLS BELOW 15 DEGREES BELOW ZERO ARE LIKELY THERE BEFORE 12Z MONDAY...SO STARTED A WIND CHILL WATCH AT 10Z MONDAY. WE INCLUDED THE WHOLE FORECAST AREA AS THE SHORT TERM WILL SHOW THAT ALL COUNTIES SEE WIND CHILLS WELL BELOW NEGATIVE 15 BY MONDAY NIGHT. WILL GO ON THE LOW SIDE OF GUIDANCE FOR TEMPERATURES SUNDAY NIGHT BASED ON TRENDS AND SNOW PACK. && .SHORT TERM /MONDAY THROUGH TUESDAY/... ISSUED AT 326 PM EST SAT JAN 25 2014 TEMPERATURES...AND WIND CHILLS WILL BE THE MAIN ISSUE WITH THE SHORT TERM. MODELS IN GOOD AGREEMENT THAT THE AXIS OF ARCTIC HIGH PRESSURE WILL BE ALONG THE MISSISSIPPI VALLEY MONDAY NIGHT AND OHIO VALLEY BY TUESDAY. SURFACE PRESSURE GRADIENT WILL BE STRONG JUST AHEAD OF THE RIDGE...ON MONDAY WITH GUSTS IN THE 20S. THEN...WINDS WILL DIE OFF A BUT MONDAY NIGHT. HOWEVER...WITH OVERNIGHT LOWS EXPECTED TO REACH 15 DEGREES BELOW ZERO OR LOWER UNDER CLEARING SKIES...WIND CHILLS WILL BE NEAR MINUS 40 DEGREES ACROSS OUR FAR NORTH. THE SOUTH WILL ALSO BE COLD BUT NOT QUITE AS COLD WITH LOWS 5 TO 10 DEGREES BELOW ZERO POSSIBLE AND WIND CHILLS TO MINUS 20. TEMPERATURES AND WIND CHILLS SHOULD BE VERY NEAR WHAT THEY WERE AFTER THE SNOW STORM OF JANUARY 5TH OF THIS YEAR. DESPITE PLENTY OF SUNSHINE...WITH THE COLDEST 925 MILLIBAR TEMPERATURES OF 27 BELOW ON MONDAY NIGHT AND TUESDAY...NORTHERN COUNTIES WILL PROBABLY NOT EVEN WARM UP TO ZERO ON TUESDAY. && .LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... ISSUED AT 231 PM EST SAT JAN 25 2014 A SLOW WARM UP IS PROGGED FOR THE EXTENDED. TEMPERATURES START OUT BITTERLY COLD TUESDAY NIGHT WITH LOWS AGAIN SEVERAL DEGREES BELOW ZERO. HOWEVER ON WEDNESDAY THE UPPER PATTERN STARTS TO FLATTEN OUT AND TEMPERATURES WILL SLOWLY MODERATE THROUGH SATURDAY WITH HIGHS WEDNESDAY IN THE TEENS AND THEN 20S ON THURSDAY AND FRIDAY. GFS AND ECMWF CONTINUE TO SHOW A WAVE MOVING THROUGH THURSDAY THAT WILL BRING SNOW TO THE AREA SO WENT WITH CHANCE POPS GIVEN FROM INITIALIZATION. BY FRIDAY NIGHT/SATURDAY LOOKS LIKE WARM ADVECTION AND A SYSTEM MOVING UP FROM THE CENTRAL PLAINS WITH ACCESS TO MOISTURE. UNCERTAINTY CONCERNING HOW QUICKLY THE COLUMN WILL WARM AND SATURATE SO WILL INCLUDE A CHANCE FOR A RAIN SNOW MIX. MADE MINOR MODIFICATIONS TO THE INITIALIZATION FOR COLLABORATION PURPOSES. && .AVIATION /DISCUSSION FOR THE 260600Z TAF ISSUANCE/... ISSUED AT 1145 PM EST SAT JAN 25 2014 MVFR OR LOWER CONDITIONS DEVELOPING MAINLY NORTH OF I-70 WITHIN SNOW NEAR DAYBREAK. HIGH PRESSURE PASSING BY TO THE SOUTH WITH MAINLY CLEAR SKIES. MID AND HIGH LEVEL CLOUDS AHEAD OF THE NEXT CLIPPER DIVING OUT OF THE DAKOTAS ALREADY RAPIDLY APPROACHING THE FORECAST AREA HOWEVER...AND EXPECT SKIES TO CLOUD UP BY 09-10Z. MODEL SOUNDINGS SHOWING DRIER AIR WITHIN THE BOUNDARY LAYER LINGERING INTO THE DAY...WHICH MAY LIMIT SNOWFALL A BIT. ADDITIONALLY...SWATH OF STEADIER SNOW APPEARS TO BE SLIGHTLY FURTHER NORTH THAN PREVIOUSLY THOUGHT. MAIN IMPACTS FROM SNOW LIKELY TO BE CONFINED TO KLAF...AND POSSIBLY KIND AT TIMES...THROUGH MIDDAY SUNDAY. WINDS WILL BECOME GUSTY YET AGAIN BY MIDDAY WITH BLOWING SNOW ONCE AGAIN AN ISSUE AT ALL TERMINALS. MAX GUSTS SHOULD REMAIN AT 25-30KTS THROUGH THE AFTERNOON. BULK OF THE SNOW WILL SHIFT EAST BY THE AFTERNOON AS WELL WITH WINDS SHIFTING TO A MORE WESTERLY DIRECTION. ARCTIC FRONT POISED TO SWING INTO THE REGION THIS EVENING...LIKELY PASSING THROUGH THE TERMINALS FROM 03-06Z. SHALLOW INSTABILITY AND STEEP LOW LEVEL LAPSE RATES SUGGESTIVE OF A BAND OR BANDS OF SNOW TO ACCOMPANY THE FRONT NEAR THE END OF THE FORECAST PERIOD...LIKELY BRINGING IFR OR WORSE CONDITIONS ALONG WITH WIND GUSTS IN EXCESS OF 30KTS FOR A PERIOD OF TIME. && .IND WATCHES/WARNINGS/ADVISORIES... WIND CHILL WATCH FROM LATE SUNDAY NIGHT THROUGH WEDNESDAY MORNING FOR INZ021-028>031-035>049-051>057-060>065-067>072. WINTER WEATHER ADVISORY FROM 4 AM SUNDAY TO 7 AM EST MONDAY FOR INZ021-028>031-035>049-057. && $$ SYNOPSIS...MK NEAR TERM...MK/RYAN SHORT TERM...MK LONG TERM...CP AVIATION...RYAN/JP VISIT US AT HTTP://WWW.WEATHER.GOV/IND FOLLOW US ON TWITTER AND YOUTUBE AT: WWW.TWITTER.COM/NWSINDIANAPOLIS WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS GRAY ME
1250 AM EST SUN JAN 26 2014 .SYNOPSIS... A COLD FRONT WILL CROSS THE REGION THIS EVENING. A WEAK RIDGE OF HIGH PRESSURE FOLLOWS FOR SUNDAY. A WARM FRONT WILL LIFT INTO THE REGION SUNDAY NIGHT AHEAD OF LOW PRESSURE MOVING EAST OUT OF THE GREAT LAKES. LOW PRESSURE WILL MOVE EAST THROUGH SOUTHERN QUEBEC ON MONDAY DRIVING A TRAILING COLD FRONT THROUGH THE REGION. HIGH PRESSURE ATTEMPTS TO BUILD IN FROM THE SOUTH MONDAY NIGHT THROUGH THURSDAY. A COLD FRONT WILL APPROACH FROM THE WEST THURSDAY NIGHT BEFORE CROSSING THE AREA. && .NEAR TERM /THROUGH SUNDAY/... 1250 AM UPDATE...MINOR ADJUSTMENTS TO THE GOING FORECAST BASED ON LATEST TRENDS IN OBERVATIONAL DATA. ARCTIC FRONT ACROSS VT WILL SWEEP ACROSS NH AND ME OVER THE NEXT 1-3 HOURS. ISOLD SNOW SQUALLS ARE POSSIBLE AND RAPID TEMPERATURE DROPS ARE EXPECTED. 9 PM UPDATE... HAVE UPDATED GRIDS BASED ON CURRENT CONDITIONS ACROSS MAINE AND NEW HAMPSHIRE. LATEST RADAR IMAGERY CONTINUES TO SHOW AREAS OF SNOW SHOWERS AND FLURRIES MOVING RAPIDLY ACROSS THE REGION FROM SOUTHWEST TO NORTHEAST. IN NEW YORK STATE...A LONG LINE OF SNOW SHOWERS AND ISOLATED SNOW SQUALLS ASSOCIATED WITH THE ARCTIC FRONT WILL CONTINUE TO PROGRESS TO THE EAST...REACHING WESTERN NEW HAMPSHIRE AROUND 07Z. THE INTENSITY OF THIS BAND SHOULD WEAKEN GRADUALLY AS IT MOVES INTO OUR FORECAST AREA. NEVERTHELESS...AN INCH OR TWO OF SNOWFALL WILL OCCUR IN MANY AREAS OVERNIGHT. USED WIND EFFECT TOOL TO BRING SLIGHTLY MORE SNOWFALL TO THE MOUNTAINS LATE TONIGHT AS WNW FLOW DEVELOPS. ADJUSTMENTS WERE MADE TO INCREASE POPS OVER THE NEXT FEW HOURS. OTHERWISE...JUST A FEW MINOR ADJUSTMENTS TO THE FORECAST. MOST RECENT HRRR RUNS ARE NOT AVAILABLE FOR THIS PACKAGE. PREV DISC...AT 19Z...A 984 MILLIBAR LOW WAS OVER WESTERN QUEBEC WITH TRAILING COLD FRONTS THROUGH THE EASTERN GREAT LAKES. THE LOW WILL TRACK TO NEAR THE GASPE PENINSULA BY 12Z SUNDAY DRAGGING THE COLD FRONTS QUICKLY EASTWARD ACROSS THE FORECAST AREA. WE`LL SEE A FEW SNOW SHOWERS ALONG AND AHEAD OF THESE BOUNDARIES WITH THE BEST CHANCE FOR AN INCH OR TWO OF ACCUMULATION FROM THE CONNECTICUT VALLEY NORTHEASTWARD ACROSS THE HIGHER TERRAIN INTO THE MAINE MOUNTAINS AND FOOTHILLS. ANOTHER AREA WITH SEVERAL INCHES OF ACCUMULATION MAYBE JUST INLAND FROM THE MID COAST WHERE OCEAN EFFECT CONTINUES. ALONG THE IMMEDIATE MID COAST...THE STRONG SOUTH-SOUTHWEST WIND HAS PUSHED TEMPERATURES UP WELL INTO THE 30S WHERE MELTING AND THE POSSIBILITY OF A MIX WITH OR BRIEF CHANGE TO RAIN WILL LIMIT ANY ACCUMULATION. THE WIND ADVISORY REMAINS IN EFFECT UNTIL 7 PM AS FUNNELING BETWEEN THE VARIOUS PENINSULA`S MAY PRODUCE LOCALIZED GUSTS TO NEAR 50 MPH. IN THE WAKE OF THE SECOND FRONTAL PASSAGE...WE`LL SEE A FEW LINGERING CLOUDS AND UPSLOPE SNOW SHOWERS ACROSS THE MOUNTAINS FOR THE BALANCE OF THE NIGHT. && .SHORT TERM /SUNDAY NIGHT/... FAIR...BUT VERY COLD AND WINDY ON SUNDAY AS ARCTIC AIR DEEPENS ACROSS THE REGION ONCE AGAIN. HIGH TEMPERATURES WILL MAX OUT A GOOD 15 TO 20 DEGREES BELOW NORMAL...WITH AN APPRECIABLE WIND CHILL. IT`S LIKELY WE`LL SEE WIND CHILL HEADLINES POSTED FOR AT LEAST THE HIGHER TERRAIN DURING THE DAY ON SUNDAY. WINDS DROP OFF BY SUNDAY EVENING AS A WEAK RIDGE CRESTS ACROSS THE AREA. TEMPERATURES DROP OFF QUICKLY AFTER DUSK THEN SHOULD STABILIZE AS CLOUDS ARRIVE TOWARDS MIDNIGHT AHEAD OF THE NEXT DISTURBANCE...WITH LIGHT OVERRUNNING SNOWS BREAKING OUT MAINLY NORTH OF A LEBANON /KLEB/ TO PORTLAND /KPWM/ LINE IN THE PREDAWN HOURS ON MONDAY. && .LONG TERM /MONDAY THROUGH SATURDAY/... DEEPLY AMPLIFIED MEAN TROUGHING REMAINS OVER THE EASTERN CONUS WITH SHORT WAVE ENERGY USHERING IN REINFORCING COLD AIR EVERY 24-36 HOURS OVER THE NORTHEAST. THE NEXT IN A SERIES OF LOW PRESSURE SYSTEMS WILL MOVE OUT OF THE GREAT LAKES REGION SUNDAY NIGHT INTO MONDAY. THIS WILL TRIGGER SCATTERED WARM ADVECTION SHOWERS OVER THE REGION. MOISTURE RETURN ISN`T GOOD AND ISENTROPIC LIFT IS NOT SIGNIFICANT WITH THIS SYSTEM AS ANOTHER QUICK MOVING COLD FRONT SHUTS PRECIPITATION OFF RELATIVELY QUICKLY. STORM TOTAL SNOW AMOUNTS WILL BE NEAR 1-3 INCHES WITH HIGHER AMOUNTS ACROSS THE FAR NORTH AND OVER THE MIDCOAST. DENSE POLAR HIGH PRESSURE SPILLS INTO THE CENTRAL CONUS MONDAY AND ATTEMPTS TO BUILD INTO NEW ENGLAND. IT SUCCEEDS IN HOLDING OFF THE NEXT SPOKE OF UPPER LEVEL ENERGY UNTIL THE THURSDAY/FRIDAY TIME FRAME...WHEN ANOTHER COLD FRONT MOVES THROUGH. BY THIS TIME THE UPPER LEVEL PATTERN WILL HAVE MODERATED SOMEWHAT AND UPPER LEVEL TRAJECTORIES SHOW THE COLDEST AIR WITH THIS SYSTEM REMAINS OVER CENTRAL CANADA...WITH THE ZERO DEGREE SURFACE ISOTHERM JUST NORTH OF THE BORDER. AFTER A WARM UP INTO THE 20S AND 30S MONDAY...TEMPERATURES DROP OFF ONCE AGAIN THROUGH WEDNESDAY WITH LOWS FROM NEAR ZERO TO -10 DEGREES F AND HIGHS IN THE SINGLE DIGITS NORTH TO UPPER TEENS/20S SOUTH. A SW/W WIND CONTRIBUTES TOWARDS A GRADUAL WARM UP TOWARDS THE END OF THE WEEK WITH HIGHS IN THE 20S AND 30S BEFORE THE NEXT FROPA. && .AVIATION /01Z SUNDAY THROUGH THURSDAY/... SHORT TERM /THROUGH SUNDAY NIGHT/...AREAS OF MVFR IN SNOW SHOWERS TONIGHT WITH WND GUSTS TO 25 KT. VFR SUNDAY WITH SFC WND GUSTS TO 25 KT. AREAS OF MVFR DEVELOPING AFT 06Z MON IN LIGHT SNOW. LONG TERM...AREAS OF LIFR/IFR/MVFR BECOMING VFR MONDAY BY NOON AS SHOWERS MOVE EAST. ADDITIONAL STRATUS/FOG POSSIBLE FOR THE IMMEDIATE COAST AND IN THE MOUNTAINS FOR LATE NIGHT/EARLY MORNING PERIODS TUESDAY THROUGH THURSDAY WITH TRAPPED LOW LEVEL MOISTURE. WESTERLY WINDS MAY BE GUSTY MONDAY AND AGAIN TUESDAY. && .MARINE... SHORT TERM /THROUGH SUNDAY NIGHT/...GALES FOR ALL WATERS INTO THIS EVENING FOR GUSTS UP TO 45 KT. A BREAK IN THE GALES IS EXPECTED FOR A TIME TONIGHT BEFORE THEY REDEVELOP BEHIND AN ARCTIC FRONT EARLY SUNDAY. WE SHOULD SEE MODERATE FREEZING SPRAY RETURN DURING THE DAY ON SUNDAY AS WELL...HENCE A FREEZING SPRAY ADVISORY HAS BEEN ISSUED. LONG TERM...ON MONDAY AND TUESDAY...WINDS SHOULD BE BORDERLINE SMALL CRAFT ADVISORY LEVELS...HOWEVER WAVES WILL REMAIN ABOVE 5 FT AS A COLD FRONT CROSSES THE WATERS. SEAS CALM DOWN SOMEWHAT FOR THE MIDWEEK PERIOD BEFORE INCREASING AGAIN THURSDAY/FRIDAY. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...WIND CHILL ADVISORY FROM 5 AM TO 4 PM EST SUNDAY FOR MEZ007>009. NH...WIND CHILL ADVISORY FROM 5 AM TO 4 PM EST SUNDAY FOR NHZ001- 002. MARINE...FREEZING SPRAY ADVISORY FROM 5 AM TO 5 PM EST SUNDAY FOR ANZ150>154. GALE WARNING UNTIL 4 PM EST SUNDAY FOR ANZ150>154. && $$
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
324 AM CST Sun Jan 26 2014 .SHORT TERM: (Through Late This Afternoon) Issued at 310 AM CST Sun Jan 26 2014 Big warm-up on tap for today with well-above average temps. Winds have already swung around to southerly overnight and temps have been slowly creeping upward. The warm front now extending from the surface low in north central Iowa into western MO will surge eastward across the CWA this morning as the surface low moves into the Great Lakes, with winds veering to southwest and then westerly and strong warm advection across the area. I have boosted temps from the previous forecast and am close to the last few hourly runs of the RAP which appear to have a good handle on the current temperatures here and upstream. Highs in most locations should get into the 50s. Enjoy the warmth...it ends tonight! Glass .LONG TERM: (Tonight through Saturday) Issued at 310 AM CST Sun Jan 26 2014 A powerful Arctic cold front will drive like a freight train through the CWA tonight. A strong pressure gradient and large pressure rises behind the front all point to very strong and gusty NW winds with the fropa. Have issued a wind advisory for all but southeast Missouri anticipating a 3-4 period with sustained winds of 25-35 mph and gusts of 45+. In addition to intense cold advection and plummeting temperatures, it appears that strong low level frontogenetic forcing and weak large scale ascent will produce a narrow band of snow immediately in the cold air. The band will be moving so quickly and the wind blowing so hard that any accumulations will be very light. Dangerous wind chills of 15 to 20 below zero are still on target late tonight and into Tuesday morning across northeast MO into central IL due to various combinations of the wind and bitterly cold ambient air temperatures. The previously issued wind chill advisory looks right on target for the anticipated high threat area. The bitterly cold Arctic air mass will dominate the area into Tuesday, and will be the coldest since the early January Arctic Outbreak. During the later half of the week ahead and into next weekend the upper air pattern finally breaks down. The longwave trof which has dominated eastern NOAM for weeks will weaken and shift northeastward as amplfication occurs from the eastern Pacific into the western U.S. and the negative phase of the PNA pattern becomes established. There are some important differences in the deterministic model solutions during this time frame with regards to shortwave features with the developing wsw flow aloft, the location of a baroclinic zone and the depth/magnitude of cold air. This leads to greater uncertainty than normal in the details, however all guidance points to increasing precipitation chances next weekend and potential for wintery precipitation. Glass && .AVIATION: (For the 06z TAFs through 06z Sunday Night) Issued at 1139 PM CST Sat Jan 25 2014 Low level wind shear continues to be the primary focus for the rest of the night. A 50-60kt low level jet between 1000-2000ft will develop over the next 2 to 6 hours from north to south ahead of the next clipper to affect the region. Wind shear conditions will persist until mid-morning when the low level inversion will mix out and winds will begin to gust. Luckily by that time it looks like the clipper will have turned the corner and begun moving away so gusts should only be around 25kts across most of the area. VFR flight conditions are expected to prevail through Sunday afternoon into the early evening. A sharp cold front will move into the area between 00Z and 03Z Sunday evening. The front will barrel through the area like a freight train with the wind turning sharply to the north-northwest. Sustained winds in excess of 30kts with gusts to 40kts or more look likely for several hours behind the front. Some light snow also looks possible. Unsure how low the ceilings will go, but MVFR is likely behind the front with conditions possibly slipping to IFR in the snow showers. Specifics for KSTL: Low level wind shear continues to be the primary focus for the rest of the night. A 50-60kt low level jet between 1000-2000ft will develop toward 10Z ahead of the next clipper to affect the region. Wind shear conditions will persist until mid-morning when the low level inversion will mix out and winds will begin to gust. Luckily by that time it looks like the clipper will have turned the corner and begun moving away so gusts should be 25kts or less. VFR flight conditions are expected to prevail through Sunday afternoon into the early evening. A sharp cold front will pass across the terminal between 04-05Z. The front will barrel through the area like a freight train with the wind turning sharply to the north- northwest. Sustained winds in excess of 25kts with gusts to 40kts or more look likely for several hours behind the front. Some light snow also looks possible. Unsure how low ceilings will go, but MVFR is likely behind the front with conditions possibly slipping to IFR in the snow showers. Carney && .PRELIMINARY POINT TEMPS/POPS: Saint Louis 56 6 12 0 / 5 30 0 0 Quincy 49 -1 5 -7 / 10 40 0 0 Columbia 56 6 13 -2 / 0 30 0 0 Jefferson City 58 8 14 -1 / 0 30 0 0 Salem 51 6 10 -2 / 5 30 5 0 Farmington 58 10 15 -1 / 0 30 5 0 && .LSX WATCHES/WARNINGS/ADVISORIES: MO...WIND ADVISORY from 8 PM this evening to 6 AM CST Monday FOR Audrain MO-Boone MO-Callaway MO-Cole MO-Franklin MO- Gasconade MO-Jefferson MO-Knox MO-Lewis MO-Lincoln MO- Marion MO-Moniteau MO-Monroe MO-Montgomery MO-Osage MO-Pike MO-Ralls MO-Shelby MO-St. Charles MO-St. Louis City MO-St. Louis MO-Warren MO. WIND CHILL ADVISORY from 3 AM Monday to Noon CST Tuesday FOR Knox MO-Lewis MO-Marion MO-Monroe MO-Pike MO-Ralls MO- Shelby MO. IL...WIND ADVISORY from 8 PM this evening to 6 AM CST Monday FOR Adams IL-Bond IL-Brown IL-Calhoun IL-Clinton IL-Fayette IL- Greene IL-Jersey IL-Macoupin IL-Madison IL-Marion IL-Monroe IL-Montgomery IL-Pike IL-Randolph IL-St. Clair IL- Washington IL. WIND CHILL ADVISORY from 3 AM Monday to Noon CST Tuesday FOR Adams IL-Brown IL-Calhoun IL-Fayette IL-Greene IL-Jersey IL- Macoupin IL-Montgomery IL-Pike IL. && $$ WFO LSX
AREA FORECAST DISCUSSION
NWS HASTINGS NE
330 AM CST SUN JAN 26 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 324 AM CST SUN JAN 26 2014 TURNING WINDY AND SHARPLY COLD DURING THE SHORT TERM PERIODS. THE WEATHER PATTERN WILL BE UNDERGOING CHANGES DURING THE SHORT TERM PERIODS AS ENERGY ROTATES AROUND THE UPPER LOW IN THE VICINITY OF THE HUDSON BAY AND AND SWINGS ACROSS THE INTERIOR CONUS...ALLOWING ARCTIC AIR TO PLUNGE SOUTH ACROSS THE CENTRAL PLAINS THIS AFTERNOON AND TONIGHT. THIS WILL BRING A DRASTIC END TO OUR WARMER TEMPERATURES THE LAST COUPLE OF DAYS AS SHARPLY COLDER AIR ARRIVES ABOARD INTENSE NORTHERLY WINDS. CURRENTLY A SFC LOW PRESSURE SYSTEM WAS SLIDING EAST ACROSS IA EARLY THIS MORNING AND IN STEADY/GUSTY WESTERLY WINDS BEHIND THE SYSTEM TEMPS HAVE REMAINED MILD IN THE 40S AND 50S. AS SOME MID LEVEL WARM AIR HAS MIXED TO THE SFC THE TEMP AT ORD JUMPED TO 53 DEGREES WHICH WILL LIKELY BE THE CALENDAR DAY HIGH FOR THIS AREA TODAY. UPSTREAM...THE ARCTIC AIRMASS WAS ADVANCING SOUTH THRU CANADA TOWARDS THE DAKOTAS. THE MORNING HOURS INTO THE FIRST PART OF THE AFTERNOON WILL CONTINUE TO FEATURE MILD WEATHER WITH STEADY/GUSTY WINDS WITH WINDS TRENDING UP FURTHER BY LATE MORNING AS MIXING INCREASES/DEEPENS. THE AFTERNOON HOURS INTO THE EVENING WILL SEE THE BIGGER WEATHER CHANGES AS THE ARCTIC FRONT MOVES INTO OUR NORTHERN ZONES AROUND 21Z OR SHORTLY THEREAFTER. THE ARCTIC FRONT REACHES THE NEB/KS STATELINE BY 00Z AND CLEARS OUR CWA BY 03Z. TEMPS WILL RAPIDLY FALL IN THE ARCTIC AIRMASS N/S THIS AFTN/EVENING. MODELS CONTINUE TO PROG VERY IMPRESSIVE THREE HOUR PRESSURE RISES BEHIND THE FRONT ON THE ORDER OF 12MB. THE TIGHT PRESSURE GRADIENT...DEEP MIXING AS HIGH AS H8 WILL LEAD TO INTENSE WINDS DEVELOPING MID TO LATE AFTERNOON ACROSS OUR NORTH AND SPREADING SOUTHWARD WITH THE FRONT THIS EVENING AND TONIGHT. GIVEN THE STRONG WINDS/WIND GUSTS WILL GO AHEAD WITH A WIND ADVISORY HEADLINE BEGINNING THIS AFTERNOON AND CONTINUING INTO THE FIRST PART OF THE NIGHT UNTIL THE GRADIENT RELAXES. STILL HAVE CONCERNS FOR REACHING HIGH WIND WARNING ACROSS OUR NORTHEAST ZONES WHERE WINDS AT THE TOP OF THE MIXED LAYER PER RAP SOUNDINGS AVERAGE NEAR 50KTS AND THIS WILL NEED TO BE MONITORED CLOSELY TODAY...AND WIND ADVISORY MAY NEED TO BE UPGRADED TO WARNING IF WINDS TREND UP MUCH FURTHER. HAVE ALSO MAINTAINED AN OUTSIDE CHC FOR SPRINKLES/FLURRIES IN FRONTOGENESIS...BUT DO NOT EXPECT MUCH MORE THAN THAT WITH LLVL MOISTURE LACKING. TONIGHT...A 1040MB SFC RIDGE BUILDS SOUTHEAST FM THE DAKOTAS ONTO THE PLAINS...AND WIND SPEEDS WILL GRADUALLY DECREASE TOWARD MORNING AS THE GRADIENT RELAXES. IN THE ARCTIC AIRMASS TEMPERATURES BOTTOM OUT IN THE SINGLE DIGITS ABOVE/BELOW ZERO. THE COMBINATION OF THE COLD TEMPS IN THE ARCTIC AIR WITH THE STEADY WINDS WILL LEAD TO FRIGID WIND CHILLS AT WIND CHILL ADVISORY CRITERIA ACROSS PORTIONS OF SOUTH CENTRAL NEBRASKA. A WIND CHILL ADVISORY WILL BE POSTED FOR LOCATIONS IN NEBRASKA ALONG/NORTH OF INTERSTATE 80 WHERE THE COLDEST WIND CHILL READINGS ARE EXPECTED FOR THE LONGEST DURATION. IF TEMPS TREND LOWER OR WINDS REMAIN STRONGER FARTHER SOUTH...THIS ADVISORY MAY NEED TO BE EXPANDED. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 324 AM CST SUN JAN 26 2014 MAIN FORECAST CONCERNS WILL BE WIND CHILLS EARLY MONDAY MORNING...CHANCES FOR SNOW WEDNESDAY NIGHT AND AGAIN FRIDAY THROUGH SATURDAY AND TEMPERATURES THROUGH THE PERIOD. WINDS AND COLD TEMPERATURES WILL CONTINUE TO BRING WIND CHILL READINGS DOWN TO AROUND 20 BELOW EARLY MONDAY MORNING. A COLD SURFACE HIGH PRESSURE PUSHES INTO THE CENTRAL PLAINS MONDAY THROUGH TUESDAY. THE CENTER OF THE HIGH SHOULD REMAIN TO THE EAST OF THE FORECAST AREA SO THE WINDS WILL CONTINUE AS WELL AS THE COLD TEMPERATURES. WIND CHILLS WILL BE AROUND 15 BELOW IN THE FAR NORTH AGAIN EARLY TUESDAY MORNING. AS THE SURFACE HIGH MOVES TO THE EAST TUESDAY NIGHT THERE IS WARM ADVECTION ACROSS THE AREA LATE TUESDAY NIGHT INTO WEDNESDAY. TEMPERATURES WILL BE THE WARMEST ON WEDNESDAY. BY WEDNESDAY NIGHT THERE IS AN UPPER LEVEL WAVE THAT MOVES THROUGH THE AREA AS WELL AS ANOTHER COLD FRONT. THERE IS A SLIGHT CHANCE FOR SOME LIGHT SNOW IN THE FAR NORTH AS THIS WAVE MOVES THROUGH. MODELS HAVE A FEW DIFFERENCES FOR THE FRIDAY TO SATURDAY TIME FRAME...BUT BOTH THE GFS AND THE ECMWF HAVE AT LEAST A LITTLE PRECIPITATION ACROSS THE AREA OFF AND ON. ANOTHER UPPER LEVEL WAVE MOVES THROUGH THE AREA AND THIS TIME THERE IS SOME MOISTURE TO WORK WITH. THE GFS HAS A LITTLE MORE PRECIPITATION THAN THE ECMWF...BUT BOTH HAVE A LITTLE. WILL KEEP SLIGHT CHANCES IN FOR FRIDAY THROUGH SATURDAY. TEMPERATURES SHOULD BE A LITTLE BELOW NORMAL AND THE PRECIPITATION SHOULD BE SNOW. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 1111 PM CST SAT JAN 25 2014 THE FOCUS FOR THE TAF PERIOD WILL BE ON WINDS. A SURFACE TROUGH HAS MOVED EAST OF THE TERMINAL AND WINDS WILL BE STEADY/GUSTY FROM THE WEST OVERNIGHT. WINDS WILL BE EVEN STRONGER ABOVE THE SURFACE THROUGH THE OVERNIGHT HOURS AND INTO SUNDAY MORNING AND HAVE MAINTAINED LLWS IN THE TAF. THE WINDS BEGIN TO MIX TO THE SURFACE BY LATE MORNING ON SUNDAY AND WINDS WILL SWITCH NORTHWESTERLY. BY LATE AFTERNOON OR TOWARD SUNDAY EVENING...AN ARCTIC COLD FRONT WILL CROSS KGRI WITH WINDS BECOMING NORTHERLY AND WIND SPEEDS INCREASING FURTHER. HAVE WENT WITH SUSTAINED WINDS AROUND 30KTS WITH GUSTS OF 40KTS OR GREATER POSSIBLE. THE WINDS WILL REMAIN STRONG/GUSTY IN A TIGHT PRESSURE GRADIENT THRU THE EVENING HOURS OF THE TAF PERIOD. && .GID WATCHES/WARNINGS/ADVISORIES... NE...WIND ADVISORY FROM 2 PM THIS AFTERNOON TO MIDNIGHT CST TONIGHT FOR NEZ072>077-082>087. WIND ADVISORY FROM NOON TODAY TO MIDNIGHT CST TONIGHT FOR NEZ039>041-046>049-060>064. WIND CHILL ADVISORY FROM 2 AM TO 10 AM CST MONDAY FOR NEZ039>041- 046>049-060>064. KS...WIND ADVISORY FROM 6 PM THIS EVENING TO 2 AM CST MONDAY FOR KSZ005>007-017>019. && $$ SHORT TERM...FAY LONG TERM...JCB AVIATION...FAY
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
253 AM CST SUN JAN 26 2014 .SHORT TERM...(TODAY THROUGH TUESDAY) ISSUED AT 253 AM CST SUN JAN 26 2014 ...VERY WINDY THIS AFTERNOON AND EVENING THEN BITTER COLD LATE TONIGHT AND EARLY MONDAY... FAIRLY COMPLEX FORECAST SETTING UP THROUGH THE SHORT TERM AS THE NEXT IN A SERIES OF ARCTIC FRONTS SWEEPS ACROSS THE REGION THIS AFTERNOON. THE CLIPPER SYSTEM THAT MOVED TO OUR NORTH AND EAST EARLIER THIS MORNING HAS LEFT US WITHIN A VERY MILD REGIME WITH TEMPS EARLY THIS MORNING SIGNIFICANTLY WARMER THAN PREVIOUSLY THOUGHT IN THE 40S TO NEAR 50. WHILE TEMPS WILL COOL A BIT THROUGH DAYBREAK...IT`S GOING TO BE ON THE MILD SIDE AHEAD OF THE ARCTIC FRONT. ARRIVAL OF ARCTIC FRONT IS STILL ON SCHEDULE...MOVING INTO NORTHEAST NEBRASKA 18-21Z...AND THE REMAINDER OF THE REGION 21-00Z. HAVE NO DOUBT WE`LL MEET WIND ADVISORY CRITERIA TODAY...THE BIG QUESTION IS IF WIND GUSTS WILL BE STRONG ENOUGH TO MEET HIGH WIND WARNING CRITERIA...AS THEY HAVE WITH SEVERAL PREVIOUS FRONTS OVER THE LAST COUPLE OF WEEKS. SOUNDINGS STILL SUGGEST THAT WE`LL MIX VERY DEEP WITH THE ARRIVAL OF THE ARCTIC AIR UP TO 750/725 MB. WINDS AT THIS LEVEL WILL BE QUITE STRONG AT 60 TO 70 KNOTS. NAM AND RAP ARE THE MOST AGGRESSIVE WITH THE WIND GUST POTENTIAL BOTH SUGGESTING THAT SURFACE WINDS COULD GUST TO 50 KNOTS OR SLIGHTLY HIGHER. OTHER MODEL SUITES AREN`T QUITE AS STRONG. COMPOUNDING THE ARRIVAL OF THE WINDS...THERE COULD BE SCATTERED SHOWERS THAT DEVELOP...INITIALLY RAIN AND THEN SNOW...WHICH WILL HELP WITH MOMENTUM TRANSFER TO THE SURFACE. NAM DOESN`T DEVELOP MUCH PRECIPITATION...BUT NEARLY ALL OTHER MODEL SUITES DO. THERE IS SOME CONCERN THAT A CONVECTIVE SNOW BAND COULD DEVELOP WITH THE SURGE OF COLDER AIR...ESPECIALLY SHOWN BY 03Z HOPWRF RUNS. WILL HAVE TO MONITOR FOR ANY VISIBILITY DROPS ONCE THE PRECIP CHANGES TO SNOW AS WELL...AND WHETHER THERE COULD BE THE POTENTIAL FOR A QUICK HALF INCH OF SNOW IN NORTHEAST NEBRASKA AND WESTERN IOWA. HAVE OPTED TO CONVERT THE HIGH WIND WATCH INTO A HIGH WIND WARNING ALONG AND NORTH OF I80. STRONG WINDS CONTINUE INTO SUNDAY EVENING...THUS WILL HAVE AN ADVISORY FOR THE REMAINING COUNTIES... WHERE MOMENTUM MIXING MAY NOT BE AS STRONG SINCE THE SUN WILL HAVE SET BY THEN. HIGH WIND WARNING COULD EVENTUALLY BE CONVERTED INTO A WIND ADVISORY AS SEVERE GUST POTENTIAL SUBSIDES THROUGH THE EVENING...BUT WOULD BEST BE MANAGED IN THE VERY NEAR TERM WITH UPDATES BASED ON REAL TIME REPORTS. SECONDARY IMMEDIATE CONCERN FOR LATER SUNDAY NIGHT INTO EARLY MONDAY IS THE ARRIVAL OF VERY COLD TEMPS BEHIND THE ARCTIC FRONT. READINGS SHOULD DROP INTO THE SINGLE DIGITS ABOVE AND BELOW ZERO...SIMILAR TO THE ARCTIC SURGE OF LAST WEEK. WHEN COUPLED WITH WINDS STILL IN THE 10-15 MPH RANGE...THIS WILL PRODUCE WIND CHILL VALUES OF 20 TO 29 BELOW THROUGH MONDAY MORNING ALONG AND NORTH OF I80 AND ACROSS MOST OF SOUTHWEST IOWA. THUS WILL HAVE A WIND CHILL ADVISORY IN EFFECT. SURFACE HIGH PRESSURE RIDGE REMAINS ACROSS THE REGION THROUGH TUESDAY. THIS WILL RESULT IN A VERY COLD DAY MONDAY...AND SUB ZERO READINGS AGAIN MONDAY NIGHT. WINDS WILL BE LIGHTER THAN MONDAY MORNING...BUT BECAUSE IT`S COLDER...WIND CHILL VALUES WILL AGAIN DROP TO 20 TO 28 BELOW OVER SOME PARTS OF THE FORECAST AREA. STILL A COLD DAY TUESDAY. .LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY) ISSUED AT 253 AM CST SUN JAN 26 2014 FORECAST PROBLEMS WITH THE EXTENDED INVOLVE ANOTHER FRONT THAT MOVES THROUGH THE REGION WEDNESDAY NIGHT. AHEAD OF THE FRONT...DECENT POTENTIAL TO WARM BACK INTO THE 30S...THEN COLDER BEHIND IT ON THURSDAY. STILL LOOKS LIKE A SMALL CHANCE OF LIGHT SNOW WEDNESDAY NIGHT. AND STILL SOME SMALL POTENTIAL THAT IT COULD LINGER INTO THURSDAY MORNING...BUT WILL WAIT FOR ANOTHER SET OF MODEL RUNS TO FINE TUNE THAT. BIGGER CONCERN IS SETTING UP FOR FRIDAY AND SATURDAY. THE GFS IS PAINTING A FAIRLY ROBUST WAVE MOVING OUT OF THE ROCKIES GIVING US A PRETTY CHANCE OF SNOW. THE ECMWF ALSO HAVE A WAVE...BUT IS A LITTLE BIT SLOWER AND WOULD HOLD OFF UNTIL FRIDAY NIGHT. AGAIN... WILL NEED TO WAIT FOR ANOTHER DAY OF MODEL RUNS TO FINE TUNE THIS...BUT IT APPEARS THAT SNOW CHANCES MAY BE INCREASING LATE IN THE WEEK. && .AVIATION...(06Z TAFS FOR KOFK...KLNK AND KOMA.) ISSUED AT 1120 PM CST SAT JAN 25 2014 LOW PRESSURE OVER SERN SD WILL MOVE QUICKLY INTO ERN IA BY 12Z SUNDAY AND SHIFT SFC WINDS FROM SW TO NW AT TAF SITES BEFORE 09Z. HOWEVER...STRONG LOW LEVEL WINDS ABOVE THE SURFACE COULD STILL BRING WIND SHEAR CONDITIONS TO TAF SITES TONIGHT AS THESE WINDS REMAIN STRONGER WITH MORE OF NORTH COMPONENT THAN SFC WINDS. ALTHOUGH AS SURFACE WINDS BECOME NW LATER TONIGHT...WIND SHEAR COULD BECOME LESS OF A THREAT. AFTER AN INITIAL SURGE OF WIND GUSTS AS WINDS BECOME NW...WINDS SHOULD DECREASE SOME IN THE MORNING BEFORE INCREASING AGAIN TOWARD MIDDAY AS MIXING DEEPENS. AN ARCTIC FRONT THAT WILL PRESS INTO NERN NEBR AROUND OR SHORTLY AFTER NOON WILL RACE INTO SERN NEBR BY 00Z. THIS WILL PROVIDE AN ADDITIONAL BOOST TO WINDS AND SHIFT THEM TO MORE NRLY. IN ADDITION...STEEP LOW LEVEL LAPSE RATES AND STRONG COOLING BEHIND FRONT COULD BRING SCT SNOW SHOWERS DURING THE AFTN. MAIN THREAT STILL APPEARED TO BE OVER NERN NEBR WHERE A PROB30 MENTION WAS MAINTAINED IN KOFK TAF. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...HIGH WIND WARNING FROM 3 PM THIS AFTERNOON TO MIDNIGHT CST TONIGHT FOR NEZ045-050>053-065>067. WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO 10 AM CST MONDAY FOR NEZ011-012-015>018-031>034. WIND ADVISORY FROM 5 PM THIS AFTERNOON TO MIDNIGHT CST TONIGHT FOR NEZ068-078-088>093. WIND CHILL ADVISORY FROM 3 AM TO 10 AM CST MONDAY FOR NEZ030- 042>045-050>053-065>068. HIGH WIND WARNING FROM NOON TODAY TO MIDNIGHT CST TONIGHT FOR NEZ011-012-015>018-030>034-042>044. IA...HIGH WIND WARNING FROM 3 PM THIS AFTERNOON TO MIDNIGHT CST TONIGHT FOR IAZ055-056-069-079-080. WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO 10 AM CST MONDAY FOR IAZ043-055-056. WIND ADVISORY FROM 5 PM THIS AFTERNOON TO MIDNIGHT CST TONIGHT FOR IAZ090-091. WIND CHILL ADVISORY FROM 3 AM TO 10 AM CST MONDAY FOR IAZ069-079- 080-090-091. HIGH WIND WARNING FROM NOON TODAY TO MIDNIGHT CST TONIGHT FOR IAZ043. && $$ SHORT TERM...DEWALD LONG TERM...DEWALD AVIATION...CHERMOK
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
1129 PM EST SAT JAN 25 2014 .SYNOPSIS... A COLD FRONT WILL PUSH SOUTH OF THE AREA TONIGHT. HIGH PRESSURE WILL BUILD EAST ACROSS THE OHIO VALLEY LATE TONIGHT INTO EARLY SUNDAY. THE NEXT CLIPPER WILL SLIDE SOUTHEAST ACROSS THE GREAT LAKES ON SUNDAY. THE NEXT PUSH OF ARCTIC AIR WILL ARRIVE BEHIND THIS SYSTEM AS ARCTIC HIGH PRESSURE BUILDS TOWARDS THE OHIO VALLEY THROUGH MID-WEEK. && .NEAR TERM /UNTIL 6 AM SUNDAY MORNING/... I LET THE WINTER WEATHER ADVISORY EXPIRE. THE WIND CHILL ADVISORY IS IN EFFECT. THE CLOUDS SHOULD DECREASE SOME LATE TONIGHT AND TEMPERATURES SHOULD DROP AND WITH THE WIND...WIND CHILL ADVISORY CRITERIA WILL BE MET. THE LAKE EFFECT SNOW SHOWERS OFF OF LAKE ERIE WERE DECREASING WHILE A BAND OF LAKE EFFECT FROM LAKE MICHIGAN INTO WOOD COUNTY WAS PRODUCING SOME SNOW. BOTH BANDS WILL DECREASE AFTER MIDNIGHT AS THE WINDS AT 925 MB SHIFTS FROM THE NW TO THE WEST AND THEN THE SW BY DAYBREAK. INCREASED THE POPS FOR A FEW HOURS OVER NW OHIO AND ADDED AN INCH OR TWO OF SNOW. THE BANDS OF SNOW OVER NE OHIO WILL SHIFT A LITTLE. NO OTHER CHANGES TO THE TEMPERATURES. PREVIOUS DISCUSSION... WINTER WEATHER ADVISORIES REMAIN IN EFFECT UNTIL 10 PM. SNOW SQUALLS HAVE INTENSIFIED ACROSS NORTHEAST OHIO SINCE 1 PM AS THE COLD FRONT MOVES SOUTHEAST ACROSS THE AREA AND THE UPPER LEVEL TROUGH BEARS DOWN UPON US. THERE IS A CONVECTIVE COMPONENT TO THE SNOW SQUALLS AS THE COLD POOL ALOFT ARRIVES. SNOW MAY BE HEAVY AT TIMES THROUGH 7 PM...BUT THE TREND WILL BE TO PUSH INLAND INTO THIS EVENING AND WEAKEN AS THE SURFACE TROUGH PUSHES SOUTH. 1000-850MB OMEGA HAS BEEN DOING A GOOD JOB HIGHLIGHTING THIS THREAT AND BOTH THE NAM12 AND RUC13 SHOWS THE PEAK HAS OCCURRED. CONSIDERED CANCELLING THE ADVISORY IN NW OHIO BUT THERE IS SOME CONCERN THAT THE LAKE ENHANCED SNOW BANDS OVER NRN INDIANA WILL SPREAD INTO NW OHIO AS THE RIDGE BUILDS TO OUR SOUTH. ACCUMULATIONS WILL BE MINOR...AN INCH OR LOCALLY UP TO 2...BUT MOST AREAS WILL BE BELOW AN INCH. WINDS REMAIN GUSTY ENOUGH HOWEVER THAT THOUGHT IT WAS WORTH CONTINUING FOR A FEW MORE HOURS. WINDS WILL SHIFT TO THE WEST AND DECREASE THROUGH THE NIGHT TO AROUND 8-12 MPH BY MORNING. A WIND CHILL ADVISORY HAS BEEN ISSUED FOR THE WHOLE AREA STARTING AFTER 10 PM AS THE NEXT PUSH OF REALLY COLD AIR ARRIVES. && .SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY NIGHT/... SOUTHWEST FLOW WILL BRING THE NEXT ROUND OF WARM ADVECTION SNOW AHEAD OF THE CLIPPER THAT WILL MOVE ACROSS THE CENTRAL GREAT LAKES ON SUNDAY. SNOWFALL MAY BE AS HIGH AS 2-3 INCHES IN OUR SOUTHWESTERN COUNTIES BUT WILL ONCE AGAIN COMBINE WITH BRISK WIND TO CREATE BLOWING SNOW CONCERNS...ESPECIALLY IN NW OHIO WHERE THE LANDSCAPE IS MORE OPEN. ELSEWHERE SNOW WILL BE LESS THAN 2 INCHES. A WINTER WEATHER ADVISORY MAY BE NEEDED FOR AREAS FROM TOLEDO TO MOUNT VERNON BUT WANTED TO KEEP IT SEPARATE FROM THE CURRENT HEADLINES AS THERE WILL BE A SIZEABLE BREAK IN THE SNOW. TEMPERATURES WILL WARM ON SUNDAY AS WE GET INTO THE WARM SECTOR WITH HIGHS RANGING FROM THE UPPER TEENS IN NW PA TO UPPER 2OS IN NORTH CENTRAL OHIO. THE ASSOCIATED ARCTIC COLD FRONT PUSHES BACK SOUTH LATE SUNDAY NIGHT AND TEMPERATURES WILL FALL THROUGH THE DAY ON MONDAY. BY MONDAY NIGHT LOWS WILL FALL TO AROUND -5 DEGREES NEAR LAKE ERIE AND -10 TO -15 DEGREES INLAND. THIS WILL RESULT IN DANGEROUSLY COLD WIND CHILL VALUES NEAR -25 AND WILL BE ON THE FRINGE OF NEEDING EITHER A WIND CHILL ADVISORY OR WARNING. && .LONG TERM /TUESDAY THROUGH SATURDAY/... SOME MODERATION IN THE PATTERN IS EXPECTED BY SATURDAY AS THE POLAR VORTEX LESSONS ITS GRIP ON THE EASTERN GREAT LAKES AND RETREATS FARTHER NORTH INTO CANADA. HOWEVER ONE MORE SIGNIFICANT SHORT WAVE WILL PIVOT AROUND THE VORTEX NORTH OF THE GREAT LAKES FROM WEDNESDAY INTO FRIDAY. THE GFS AND ECMWF ARE RATHER SIMILAR THROUGH THIS PERIOD WHICH ADDS TO FORECAST CONFIDENCE. FRIGID TEMPERATURES ON TUESDAY WILL MODERATE WEDNESDAY AFTERNOON AS THE ARCTIC AIRMASS SHIFTS NORTHEAST OF THE REGION. ANOTHER COLD FRONT WILL CROSS THE REGION THURSDAY EVENING BUT WITH ONLY MODEST COOLING AND WON`T BE NEARLY AS COLD AS THE AIRMASS PRESENT OVER THE REGION ON TUESDAY. SEASONABLE COLD HIGH PRESSURE WILL BUILD OVER THE REGION ON FRIDAY AND SHIFT EAST FOR SATURDAY AS A DEVELOPING WARM FRONT MOVES NORTH INTO THE LOWER OHIO VALLEY. MIXED PRECIPITATION WILL LIKELY SPREAD INTO THE REGION ALONG WITH MODERATING TEMPERATURES. && .AVIATION /06Z SUNDAY THROUGH THURSDAY/... MULTI LAKE SNOW BANDS CONTINUE FROM LAKE MICHIGAN TO LAKE ERIE. SOME OF THE STRONGER BANDS ARE PRODUCING VISIBILITIES DOWN TO A QUARTER MILE OR LESS AT TIMES. EXPECT AS FLOW SHIFTS TO MORE SOUTHWEST THAT THESE BANDS WILL MIGRATE BACK NORTH TOWARD THE LAKE SHORE. LOW PRESSURE WILL APPROACH FROM THE WEST AS AN ALBERTA CLIPPER SYSTEM. CEILINGS AND VISIBILITIES WILL DROP WITH TIME AND THEN IMPROVE TOMORROW EVENING. WINDS WILL REMAIN UP AT A FEW LOCATIONS OTHER WISE WILL REMAIN UP THROUGH THE LATTER HALF OF THE FORECAST PERIOD. OUTLOOK...NON VFR INTO MONDAY. NON VFR MAINLY IN THE SNOW BELT MONDAY NIGHT INTO TUESDAY. && .MARINE... LAKE ERIE IS MOSTLY ICE COVERED SO WAVES ARE MINIMAL AT THIS TIME. A VERY CHANGEABLE PERIOD IS EXPECTED WITH WEATHER SYSTEMS QUICKLY CROSSING THE REGION WITH WELL DEFINED WIND FIELDS THAT SHOULD REMAIN BELOW GALE WARNING THRESHOLD THROUGH THE FORECAST PERIOD. WITH THE ARCTIC FRONT CROSSING THE LAKE THIS AFTERNOON... WINDS WILL BECOME NORTHWEST AND THEN DIMINISH OVERNIGHT. THE WIND WILL BACK TO THE SOUTHWEST AS THE NEXT CLIPPER APPROACHES FROM THE WEST AND CROSSES THE CENTRAL LAKES SUNDAY AND SUNDAY NIGHT. ARCTIC HIGH PRESSURE WILL BUILD INTO THE REGION TUESDAY AND WEDNESDAY WITH WEST TO SOUTHWEST FLOW. ANOTHER COLD FRONT WILL CROSS THE LAKE THURSDAY. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...WIND CHILL ADVISORY UNTIL 10 AM EST SUNDAY FOR OHZ003-006>014- 017>023-027>033-036>038-047-089. PA...WIND CHILL ADVISORY UNTIL 10 AM EST SUNDAY FOR PAZ001>003. MARINE...NONE. && $$ SYNOPSIS...KEC NEAR TERM...KEC/KIELTYKA SHORT TERM...KEC LONG TERM...LAPLANTE AVIATION...LOMBARDY MARINE...BC/LAPLANTE
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
706 AM EST SUN JAN 26 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 656 AM EST SUN JAN 26 2014 WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW POLAR VORTEX CENTERED OVER SRN HUDSON BAY/JAMES BAY. AROUND THE VORTEX...ONE SHORTWAVE IS SWINGING THRU THE UPPER MISSISSIPPI VALLEY. A SECOND MUCH STRONGER WAVE IS DROPPING THRU SRN MANITOBA/SRN SASKATCHEWAN. FIRST WAVE IS SPREADING AN AREA OF SNOW ACROSS MUCH OF WI/NRN IL/NRN IN. SNOW THEN EXTENDS BACK TO THE NW AHEAD OF THE STRONGER WAVE. FORCING AHEAD OF THIS WAVE IS ALREADY SUPPORTING -SN SPREADING INTO THE W HALF OF UPPER MI. STRONG WINDS OVER THE LAST 2 DAYS HAVE REALLY CHANGED THE ICE COVER ON LAKE SUPERIOR...AND THIS WILL BE A COMPLICATING FACTOR AS ICE COVER IN THE MODELS IS NOT REPRESENTATIVE OF THE CURRENT STATE OF ICE. THUS...MODELS WILL BE INCORRECTLY HANDLING WINDS/CONVERGENCE/LAKE EFFECT PCPN. THE ICE COVER THAT WAS ROUGHLY BTWN MANITOU ISLAND AND SHOT POINT WEST TO KEWEENAW BAY IS CLEARLY BROKEN UP ENOUGH TO ALLOW DECENT HEAT/MOISTURE FLUXES AS WAS EVIDENT FROM THE SIGNIFICANT LES BANDS THAT STREAMED INTO MARQUETTE/WRN ALGER COUNTIES YESTEDAY. OVER WRN LAKE SUPERIOR...THERE IS PLENTY OF OPEN WATER. A BIG PORTION OF THE ICE THAT WAS OVER WRN LAKE SUPERIOR APPEARS TO BE OVER NCNTRL LAKE SUPERIOR NOW. NOT MUCH HAS CHANGED WITH THE OVERALL FCST THINKING SINCE YESTERDAY. IMPRESSIVE DEEP LAYER FORCING WILL SPREAD ACROSS UPPER MI TODAY AS SHORTWAVE SWINGS INTO THE WRN LAKES. THERE`S NOT A LOT OF MOISTURE TO WORK WITH AS MIXING RATIOS IN THE 700-750MB LAYER ARE ONLY 0.5 TO 1G/KG. ANOTHER NEGATIVE FOR SNOW ACCUMULATIONS IS LOW SNOW TO WATER RATIOS WITH DGZ NEAR THE SFC. SIMILAR TO PREVIOUS FCSTS...EXPECT A GENERAL 1-2 INCH SNOWFALL TODAY. SMALL SNOWFLAKES WILL PROBABLY MAKE FOR LOWER VIS THAN ONE WOULD EXPECT WITH LIGHT ACCUMULATIONS. WHILE 850MB WINDS BACK ENOUGH FOR LAKE ENHANCEMENT POTENTIAL OFF LAKE MICHIGAN...AT LOWER LEVELS...WINDS REMAIN OFFSHORE AS MESOLOW DEVELOPMENT OCCURS OVER NRN LAKE MICHIGAN. AT THIS POINT...NOT EXPECTING MUCH ENHANCMENT NEAR LAKE MICHIGAN. THERE SHOULD BE SOME LAKE ENHANCEMENT NEAR LAKE SUPERIOR THIS EVENING AS WINDS SHIFT N TO NW AND STRENGTHEN WITH EXTREMELY COLD AIR SURGING INTO THE AREA BEHIND SHORTWAVE. GIVEN THE OPEN WATER...SNOW MAY BE HEAVIER THAN EXPECTED OVER THE W. EVEN SO...WITH DGZ ELIMINATED BY COLD AIR...LOW SNOW TO WATER RATIOS WILL WORK AGAINST SIGNIFICANT ACCUMULATIONS. MORE CRITICAL PART OF THE FCST IS WHAT HAPPENS OVER ERN LAKE SUPERIOR. DIMINISHING GRADIENT WIND FIELD AND STRENGTHENING LAND BREEZES ARE CURRENTLY LEADING TO MESOLOW DEVELOPMENT OVER SE LAKE SUPERIOR PER SFC/MARINE OBS. WITH STRONG FORCING PROVIDED BY SHORTWAVE...MESOLOW SHOULD REALLY SPIN UP TODAY AS IT DRIFTS N OR NW. ALL HIGH RES MODEL GUIDANCE CONTINUE TO SHOW THIS...BUT TREND HAS BEEN FOR A MORE EWD TRACK AS THE LOW HEADS BACK S WITH SHORTWAVE PASSAGE LATE AFTN/EVENING. CONSENSUS IS GENERALLY FOR LANDFALL NEAR GRAND MARAIS. A BAND OF HVY LES IS EXPECTED ON THE WRN FLANK OF THE LOW...AND MODEL GUIDANCE IS MOSTLY INDICATING THIS BAND AFFECTING THE AREA BTWN MUNISING AND GRAND MARAIS. HOWEVER...WITH MODEL ICE COVER TOO EXTENSIVE TO THE LEE OF THE KEWEENAW...WOULD EXPECT SIGNIFICANT LES TO IMPACT AREAS FARTHER W IN ALGER COUNTY EVEN IF LOW IN FACT DOES MOVE ONSHORE NEAR GRAND MARAIS. HIGH RES MODEL GUIDANCE IS IN EXCELLENT AGREEMENT ON A CORE OF STRONG LOW-LEVEL WINDS (950MB WINDS OF 40-50KT) ON THE WRN SIDE OF THE LOW AIMED TOWARD THE MUNISING AREA. COMBINED WITH MESOSCALE PRES RISE/FALL COUPLET...CONDITIONS LOOK FAVORABLE FOR BLIZZARD CONDITIONS IN ALGER COUNTY TONIGHT...ESPECIALLY BTWN DEERTON AND MUNISING. HAVE THUS CONVERTED BLIZZARD WATCH TO WARNING FOR ALGER COUNTY...AND ISSUED LES ADVY FOR NRN SCHOOLCRAFT WHERE WINDS FARTHER INLAND WON`T BE NEARLY AS SIGNIFICANT. WRN EDGE OF STRONGER WIND FIELD WILL CLIP KEWEENAW COUNTY...SO ALSO ISSUED LES ADVY THERE TONIGHT/MON MORNING FOR CONSIDERABLE BLSN THOUGH SNOW ACCUMULATIONS WILL ONLY BE 2-3 INCHES. DURING THE DAY...WILL NEED TO TAKE ANOTHER LOOK AT EXPANDING ADVY OVER WRN UPPER MI AS SUFFICIENT OPEN WATER EXISTS TO LEAD TO WIDESPREAD -SHSN WHICH WILL PRODUCE VERY LOW VIS WHEN COMBINED WITH OCNL BLSN. ELSEWHERE...CONVERTED WIND CHILL WATCH TO WARNING LATE TONIGHT AS WIND CHILLS DROP TO NEAR OR BLO -35F. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 526 AM EST SUN JAN 26 2014 PRIMARY FOCUS IN THE LONG TERM IS ON THE FIRST 2 DAYS /THROUGH TUESDAY/. FOR MON...AT 12Z THE CWA WILL BE BETWEEN A CLIPPER SYSTEM OVER FAR SERN ONTARIO AND AN UPPER TROUGH OVER NWRN LAKE SUPERIOR. AT THE SFC...THE PRESSURE GRADIENT WILL BE SHARP AS THE CLIPPER LOW DEPARTS THE REGION AND A 1040MB HIGH MOVES INTO THE NRN PLAINS STATES...AND HIGH RES MODEL INDICATE A MESO LOW OVER ERN LAKE SUPERIOR MON MORNING. ALONG THE W SIDE OF THE POSSIBLE MESO LOW WILL BE VERY STRONG WINDS AND A STRONG LES BAND THAT LOOKS TO BE OVER ALGER COUNTY. HIGH RES MODELS SHOW 925MB WINDS OF 40-50KTS W OF THE MESO LOW...WHICH WOULD CONTINUE TO LEAD TO BLIZZARD CONDITIONS FROM MON NIGHT /SEE SHORT TERM DISCUSSION/ INTO MON MORNING. BY 18Z MON...THE UPPER TROUGH IS OVER ERN LAKE SUPERIOR AND HIGH RES MODELS SHOW THE MESO LOW SHIFTING TO THE E...CAUSING THE PRESSURE GRADIENT TO WEAKEN AND NW WINDS THAT WERE AHEAD OF THE TROUGH TO BECOME MORE WLY BEHIND THE TROUGH. THIS WILL SHIFT LES WHILE WEAKENING IT DUE TO THE UPPER LEVEL SUPPORT MOVING OUT. WITH THE WORST CONDITIONS FROM THE WINDS AND SNOW MORE FOCUSED DURING SUN NIGHT /SHORT TERM FORECAST/...WILL TALK ABOUT THE COLD TEMPS FOR MON INTO MON NIGHT. 850MB TEMPS WILL BE -30C TO -35C FROM 12Z-18Z MON...WARMING TO -25C TO -30C BY 00Z TUE. THIS WILL LEAD TO HIGH TEMPS ON MON OF AROUND 0F E TO AROUND -10F WEST WITH WIND CHILLS AS LOW AS -40F /COLDEST OVER THE W HALF IN THE MORNING TO EARLY AFTERNOON/. WITH WINDS SHIFTING A LITTLE MORE WLY MON NIGHT WHILE THE COLD 850MB TEMPS AROUND -25C...CLOUDS WILL BE MORE SPARSE OVER THE INTERIOR W AND CENTRAL U.P. MON NIGHT. THIS SHOULD LEAD TO LOW TEMPS AROUND -25F OVER THE WELL INTERIOR W...WHERE WINDS WILL BE AOB 10KTS. CLOSER TO LAKE SUPERIOR...LOWS WILL BE IN THE SINGLE DIGITS TO TEENS BELOW ZERO WITH WINDS TO 15-25KTS. VERY COLD WIND CHILLS WILL CONTINUE MON NIGHT THROUGH TUE MORNING. WIND CHILLS VALUES ARE EXPECTED TO FALL TO -30F TO -45F DURING THIS TIME. LES WILL CONTINUE MON NIGHT...BUT FOR MORE WNW FAVORED SNOW BELTS. WITH WINDS REMAINING GUSTY NEAR LAKE SUPERIOR...BLOWING AND DRIFTING SNOW WILL CONTINUE. WINDS LOOK TO CONTINUE TO BARELY SHIFT MORE WLY ON TUE AS THE SFC HIGH MOVES INTO THE MID MISSISSIPPI VALLEY WHILE 850MB TEMPS INCREASE TO -20C TO -25C. THIS WILL LEAD TO CONTINUE LES IN WNW WIND SNOWBELTS. WINDS NEAR LAKE SUPERIOR ON TUE SHOULD GUST TO 30-35KTS...CONTINUING BLOWING AND DRIFTING SNOW. AFTER TUE...A CLIPPER SYSTEM MAY IMPACT THE REGION LATE WED INTO THU...WITH DETAILS OF THIS SYSTEM STILL BEING SOMEWHAT UNCERTAIN. WILL FOCUS ATTENTION TO FIRST COUPLE OF DAYS OF THE LONG TERM GIVEN IMPACTS DURING THIS PERIOD...AND USE A CONSENSUS OF GUIDANCE FOR FORECASTS DURING THE LATER HALF OF THE LONG TERM. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 705 AM EST SUN JAN 26 2014 APPROACHING DISTURBANCE WILL BRING -SN TO THE AREA TODAY. DUE TO ARCTIC AIR...SNOWFLAKES WILL BE SMALL AND THUS EFFECTIVE AT REDUCING VIS. AS A RESULT...IFR SHOULD BE THE PREVAILING CONDITION AT KIWD/KCMX/KSAW TODAY...THOUGH SOME PERIODS OF MVFR ARE ALSO LIKELY. WINDS WILL BECOME NORTHERLY THIS AFTN AND INCREASE TONIGHT. COMBINATION OF -SHSN/BLSN WILL LIKELY RESULT IN LIFR CONDITIONS AT KIWD AND ESPECIALLY KCMX WHERE WINDS WILL BE STRONGER. IFR SHOULD CONTINUE AT KSAW...BUT CONDITIONS MAY FALL TO LIFR IF SNOW IS HEAVIER OR WIND STRONGER. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 526 AM EST SUN JAN 26 2014 LOW PRESSURE SPRAWLED FROM HUDSON BAY TO QUEBEC WILL LIFT SLOWLY NEWD THROUGH MON. MEANWHILE...LOW PRESSURE OVER MINNESOTA WILL MOVE ACROSS NORTHERN LOWER MI AS IT DEEPENS THIS EVENING. IN ITS WAKE...HIGH PRESSURE OVER SASKATCHEWAN WILL SINK TO THE SE CONUS BY WED. EXPECT NW GALES TO 35 TO 40 KTS AND HEAVY FREEZING SPRAY /WHERE OPEN WATER REMAINS/ FROM SUN NIGHT THROUGH TUE UNDER THE SHARP PRESSURE GRADIENT BETWEEN THIS HIGH AND THE LOW IN QUEBEC. THE GALES AND HEAVY FREEZING SPRAY WILL SUBSIDE ON WED WITH THE ARRIVAL OF A WEAK HIGH PRESSURE RIDGE/FLATTER PRESSURE GRADIENT. LOW PRESSURE WILL MOVE FROM MANITOBA TO JAMES BAY ON THU...DRAGGING A LOW PRESSURE TROUGH ACROSS THE GREAT LAKES. MORE HEAVY FREEZING SPRAY MAY DEVELOP ON WED NIGHT AND THU UNDER THE SHARPER PRESSURE GRADIENT ASSOCIATED WITH THIS TROUGH PASSAGE. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... WIND CHILL WARNING FROM 1 AM EST /MIDNIGHT CST/ MONDAY TO 1 PM EST /NOON CST/ TUESDAY FOR MIZ001>005-009>013-084. LAKE EFFECT SNOW ADVISORY FROM 8 PM THIS EVENING TO NOON EST MONDAY FOR MIZ085. LAKE EFFECT SNOW ADVISORY FROM 7 PM THIS EVENING TO NOON EST MONDAY FOR MIZ001. BLIZZARD WARNING FROM 8 PM THIS EVENING TO NOON EST MONDAY FOR MIZ006. WIND CHILL WARNING FROM 7 AM MONDAY TO 1 PM EST TUESDAY FOR MIZ014. LAKE SUPERIOR... HEAVY FREEZING SPRAY WARNING UNTIL 7 AM EST WEDNESDAY FOR LSZ244- 245-264>267. GALE WARNING FROM 7 PM THIS EVENING TO 1 AM EST WEDNESDAY FOR LSZ249-250-266. GALE WARNING FROM 7 PM THIS EVENING TO 10 PM EST TUESDAY FOR LSZ244-245-248-264-265. LAKE MICHIGAN... NONE. && $$ SHORT TERM...ROLFSON LONG TERM...TITUS AVIATION...ROLFSON MARINE...TITUS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
656 AM EST SUN JAN 26 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 656 AM EST SUN JAN 26 2014 WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW POLAR VORTEX CENTERED OVER SRN HUDSON BAY/JAMES BAY. AROUND THE VORTEX...ONE SHORTWAVE IS SWINGING THRU THE UPPER MISSISSIPPI VALLEY. A SECOND MUCH STRONGER WAVE IS DROPPING THRU SRN MANITOBA/SRN SASKATCHEWAN. FIRST WAVE IS SPREADING AN AREA OF SNOW ACROSS MUCH OF WI/NRN IL/NRN IN. SNOW THEN EXTENDS BACK TO THE NW AHEAD OF THE STRONGER WAVE. FORCING AHEAD OF THIS WAVE IS ALREADY SUPPORTING -SN SPREADING INTO THE W HALF OF UPPER MI. STRONG WINDS OVER THE LAST 2 DAYS HAVE REALLY CHANGED THE ICE COVER ON LAKE SUPERIOR...AND THIS WILL BE A COMPLICATING FACTOR AS ICE COVER IN THE MODELS IS NOT REPRESENTATIVE OF THE CURRENT STATE OF ICE. THUS...MODELS WILL BE INCORRECTLY HANDLING WINDS/CONVERGENCE/LAKE EFFECT PCPN. THE ICE COVER THAT WAS ROUGHLY BTWN MANITOU ISLAND AND SHOT POINT WEST TO KEWEENAW BAY IS CLEARLY BROKEN UP ENOUGH TO ALLOW DECENT HEAT/MOISTURE FLUXES AS WAS EVIDENT FROM THE SIGNIFICANT LES BANDS THAT STREAMED INTO MARQUETTE/WRN ALGER COUNTIES YESTEDAY. OVER WRN LAKE SUPERIOR...THERE IS PLENTY OF OPEN WATER. A BIG PORTION OF THE ICE THAT WAS OVER WRN LAKE SUPERIOR APPEARS TO BE OVER NCNTRL LAKE SUPERIOR NOW. NOT MUCH HAS CHANGED WITH THE OVERALL FCST THINKING SINCE YESTERDAY. IMPRESSIVE DEEP LAYER FORCING WILL SPREAD ACROSS UPPER MI TODAY AS SHORTWAVE SWINGS INTO THE WRN LAKES. THERE`S NOT A LOT OF MOISTURE TO WORK WITH AS MIXING RATIOS IN THE 700-750MB LAYER ARE ONLY 0.5 TO 1G/KG. ANOTHER NEGATIVE FOR SNOW ACCUMULATIONS IS LOW SNOW TO WATER RATIOS WITH DGZ NEAR THE SFC. SIMILAR TO PREVIOUS FCSTS...EXPECT A GENERAL 1-2 INCH SNOWFALL TODAY. SMALL SNOWFLAKES WILL PROBABLY MAKE FOR LOWER VIS THAN ONE WOULD EXPECT WITH LIGHT ACCUMULATIONS. WHILE 850MB WINDS BACK ENOUGH FOR LAKE ENHANCEMENT POTENTIAL OFF LAKE MICHIGAN...AT LOWER LEVELS...WINDS REMAIN OFFSHORE AS MESOLOW DEVELOPMENT OCCURS OVER NRN LAKE MICHIGAN. AT THIS POINT...NOT EXPECTING MUCH ENHANCMENT NEAR LAKE MICHIGAN. THERE SHOULD BE SOME LAKE ENHANCEMENT NEAR LAKE SUPERIOR THIS EVENING AS WINDS SHIFT N TO NW AND STRENGTHEN WITH EXTREMELY COLD AIR SURGING INTO THE AREA BEHIND SHORTWAVE. GIVEN THE OPEN WATER...SNOW MAY BE HEAVIER THAN EXPECTED OVER THE W. EVEN SO...WITH DGZ ELIMINATED BY COLD AIR...LOW SNOW TO WATER RATIOS WILL WORK AGAINST SIGNIFICANT ACCUMULATIONS. MORE CRITICAL PART OF THE FCST IS WHAT HAPPENS OVER ERN LAKE SUPERIOR. DIMINISHING GRADIENT WIND FIELD AND STRENGTHENING LAND BREEZES ARE CURRENTLY LEADING TO MESOLOW DEVELOPMENT OVER SE LAKE SUPERIOR PER SFC/MARINE OBS. WITH STRONG FORCING PROVIDED BY SHORTWAVE...MESOLOW SHOULD REALLY SPIN UP TODAY AS IT DRIFTS N OR NW. ALL HIGH RES MODEL GUIDANCE CONTINUE TO SHOW THIS...BUT TREND HAS BEEN FOR A MORE EWD TRACK AS THE LOW HEADS BACK S WITH SHORTWAVE PASSAGE LATE AFTN/EVENING. CONSENSUS IS GENERALLY FOR LANDFALL NEAR GRAND MARAIS. A BAND OF HVY LES IS EXPECTED ON THE WRN FLANK OF THE LOW...AND MODEL GUIDANCE IS MOSTLY INDICATING THIS BAND AFFECTING THE AREA BTWN MUNISING AND GRAND MARAIS. HOWEVER...WITH MODEL ICE COVER TOO EXTENSIVE TO THE LEE OF THE KEWEENAW...WOULD EXPECT SIGNIFICANT LES TO IMPACT AREAS FARTHER W IN ALGER COUNTY EVEN IF LOW IN FACT DOES MOVE ONSHORE NEAR GRAND MARAIS. HIGH RES MODEL GUIDANCE IS IN EXCELLENT AGREEMENT ON A CORE OF STRONG LOW-LEVEL WINDS (950MB WINDS OF 40-50KT) ON THE WRN SIDE OF THE LOW AIMED TOWARD THE MUNISING AREA. COMBINED WITH MESOSCALE PRES RISE/FALL COUPLET...CONDITIONS LOOK FAVORABLE FOR BLIZZARD CONDITIONS IN ALGER COUNTY TONIGHT...ESPECIALLY BTWN DEERTON AND MUNISING. HAVE THUS CONVERTED BLIZZARD WATCH TO WARNING FOR ALGER COUNTY...AND ISSUED LES ADVY FOR NRN SCHOOLCRAFT WHERE WINDS FARTHER INLAND WON`T BE NEARLY AS SIGNIFICANT. WRN EDGE OF STRONGER WIND FIELD WILL CLIP KEWEENAW COUNTY...SO ALSO ISSUED LES ADVY THERE TONIGHT/MON MORNING FOR CONSIDERABLE BLSN THOUGH SNOW ACCUMULATIONS WILL ONLY BE 2-3 INCHES. DURING THE DAY...WILL NEED TO TAKE ANOTHER LOOK AT EXPANDING ADVY OVER WRN UPPER MI AS SUFFICIENT OPEN WATER EXISTS TO LEAD TO WIDESPREAD -SHSN WHICH WILL PRODUCE VERY LOW VIS WHEN COMBINED WITH OCNL BLSN. ELSEWHERE...CONVERTED WIND CHILL WATCH TO WARNING LATE TONIGHT AS WIND CHILLS DROP TO NEAR OR BLO -35F. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 526 AM EST SUN JAN 26 2014 PRIMARY FOCUS IN THE LONG TERM IS ON THE FIRST 2 DAYS /THROUGH TUESDAY/. FOR MON...AT 12Z THE CWA WILL BE BETWEEN A CLIPPER SYSTEM OVER FAR SERN ONTARIO AND AN UPPER TROUGH OVER NWRN LAKE SUPERIOR. AT THE SFC...THE PRESSURE GRADIENT WILL BE SHARP AS THE CLIPPER LOW DEPARTS THE REGION AND A 1040MB HIGH MOVES INTO THE NRN PLAINS STATES...AND HIGH RES MODEL INDICATE A MESO LOW OVER ERN LAKE SUPERIOR MON MORNING. ALONG THE W SIDE OF THE POSSIBLE MESO LOW WILL BE VERY STRONG WINDS AND A STRONG LES BAND THAT LOOKS TO BE OVER ALGER COUNTY. HIGH RES MODELS SHOW 925MB WINDS OF 40-50KTS W OF THE MESO LOW...WHICH WOULD CONTINUE TO LEAD TO BLIZZARD CONDITIONS FROM MON NIGHT /SEE SHORT TERM DISCUSSION/ INTO MON MORNING. BY 18Z MON...THE UPPER TROUGH IS OVER ERN LAKE SUPERIOR AND HIGH RES MODELS SHOW THE MESO LOW SHIFTING TO THE E...CAUSING THE PRESSURE GRADIENT TO WEAKEN AND NW WINDS THAT WERE AHEAD OF THE TROUGH TO BECOME MORE WLY BEHIND THE TROUGH. THIS WILL SHIFT LES WHILE WEAKENING IT DUE TO THE UPPER LEVEL SUPPORT MOVING OUT. WITH THE WORST CONDITIONS FROM THE WINDS AND SNOW MORE FOCUSED DURING SUN NIGHT /SHORT TERM FORECAST/...WILL TALK ABOUT THE COLD TEMPS FOR MON INTO MON NIGHT. 850MB TEMPS WILL BE -30C TO -35C FROM 12Z-18Z MON...WARMING TO -25C TO -30C BY 00Z TUE. THIS WILL LEAD TO HIGH TEMPS ON MON OF AROUND 0F E TO AROUND -10F WEST WITH WIND CHILLS AS LOW AS -40F /COLDEST OVER THE W HALF IN THE MORNING TO EARLY AFTERNOON/. WITH WINDS SHIFTING A LITTLE MORE WLY MON NIGHT WHILE THE COLD 850MB TEMPS AROUND -25C...CLOUDS WILL BE MORE SPARSE OVER THE INTERIOR W AND CENTRAL U.P. MON NIGHT. THIS SHOULD LEAD TO LOW TEMPS AROUND -25F OVER THE WELL INTERIOR W...WHERE WINDS WILL BE AOB 10KTS. CLOSER TO LAKE SUPERIOR...LOWS WILL BE IN THE SINGLE DIGITS TO TEENS BELOW ZERO WITH WINDS TO 15-25KTS. VERY COLD WIND CHILLS WILL CONTINUE MON NIGHT THROUGH TUE MORNING. WIND CHILLS VALUES ARE EXPECTED TO FALL TO -30F TO -45F DURING THIS TIME. LES WILL CONTINUE MON NIGHT...BUT FOR MORE WNW FAVORED SNOW BELTS. WITH WINDS REMAINING GUSTY NEAR LAKE SUPERIOR...BLOWING AND DRIFTING SNOW WILL CONTINUE. WINDS LOOK TO CONTINUE TO BARELY SHIFT MORE WLY ON TUE AS THE SFC HIGH MOVES INTO THE MID MISSISSIPPI VALLEY WHILE 850MB TEMPS INCREASE TO -20C TO -25C. THIS WILL LEAD TO CONTINUE LES IN WNW WIND SNOWBELTS. WINDS NEAR LAKE SUPERIOR ON TUE SHOULD GUST TO 30-35KTS...CONTINUING BLOWING AND DRIFTING SNOW. AFTER TUE...A CLIPPER SYSTEM MAY IMPACT THE REGION LATE WED INTO THU...WITH DETAILS OF THIS SYSTEM STILL BEING SOMEWHAT UNCERTAIN. WILL FOCUS ATTENTION TO FIRST COUPLE OF DAYS OF THE LONG TERM GIVEN IMPACTS DURING THIS PERIOD...AND USE A CONSENSUS OF GUIDANCE FOR FORECASTS DURING THE LATER HALF OF THE LONG TERM. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 1207 AM EST SUN JAN 26 2014 AS A HIGH PRESSURE RIDGE QUICKLY MOVES ACROSS UPPER MICHIGAN TONIGHT WITH WINDS BACKING SOUTHWEST...THE REMAINING LAKE CLOUDS AND LIGHT SNOW WILL LIFT OUT OF THE AREA WITH VFR CONDITIONS PREVAILING BY LATE TONIGHT AT CMX/SAW. THE NEXT CLIPPER SYSTEM WILL MOVE ACROSS UPPER MICHIGAN ON SUNDAY. ALTHOUGH WINDS WILL BE LIGHT....EXPECT THE FINE FLAKES TO AGAIN BE GOOD AT REDUCING VISIBILITIES AND HAVE LOWERED VALUES TO IFR FROM WEST TO EAST THROUGH THE MORNING HOURS. AFTER THE LIGHT SNOW DIMINISHES...EXPECT MVFR CONDITIONS TO PREVAIL THROUGHT SUNDAY EVENING. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 526 AM EST SUN JAN 26 2014 LOW PRESSURE SPRAWLED FROM HUDSON BAY TO QUEBEC WILL LIFT SLOWLY NEWD THROUGH MON. MEANWHILE...LOW PRESSURE OVER MINNESOTA WILL MOVE ACROSS NORTHERN LOWER MI AS IT DEEPENS THIS EVENING. IN ITS WAKE...HIGH PRESSURE OVER SASKATCHEWAN WILL SINK TO THE SE CONUS BY WED. EXPECT NW GALES TO 35 TO 40 KTS AND HEAVY FREEZING SPRAY /WHERE OPEN WATER REMAINS/ FROM SUN NIGHT THROUGH TUE UNDER THE SHARP PRESSURE GRADIENT BETWEEN THIS HIGH AND THE LOW IN QUEBEC. THE GALES AND HEAVY FREEZING SPRAY WILL SUBSIDE ON WED WITH THE ARRIVAL OF A WEAK HIGH PRESSURE RIDGE/FLATTER PRESSURE GRADIENT. LOW PRESSURE WILL MOVE FROM MANITOBA TO JAMES BAY ON THU...DRAGGING A LOW PRESSURE TROUGH ACROSS THE GREAT LAKES. MORE HEAVY FREEZING SPRAY MAY DEVELOP ON WED NIGHT AND THU UNDER THE SHARPER PRESSURE GRADIENT ASSOCIATED WITH THIS TROUGH PASSAGE. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... WIND CHILL WARNING FROM 1 AM EST /MIDNIGHT CST/ MONDAY TO 1 PM EST /NOON CST/ TUESDAY FOR MIZ001>005-009>013-084. LAKE EFFECT SNOW ADVISORY FROM 8 PM THIS EVENING TO NOON EST MONDAY FOR MIZ085. LAKE EFFECT SNOW ADVISORY FROM 7 PM THIS EVENING TO NOON EST MONDAY FOR MIZ001. BLIZZARD WARNING FROM 8 PM THIS EVENING TO NOON EST MONDAY FOR MIZ006. WIND CHILL WARNING FROM 7 AM MONDAY TO 1 PM EST TUESDAY FOR MIZ014. LAKE SUPERIOR... HEAVY FREEZING SPRAY WARNING UNTIL 7 AM EST WEDNESDAY FOR LSZ244- 245-264>267. GALE WARNING FROM 7 PM THIS EVENING TO 1 AM EST WEDNESDAY FOR LSZ249-250-266. GALE WARNING FROM 7 PM THIS EVENING TO 10 PM EST TUESDAY FOR LSZ244-245-248-264-265. HEAVY FREEZING SPRAY WARNING UNTIL 7 AM EST THIS MORNING FOR LSZ249>251. LAKE MICHIGAN... NONE. && $$ SHORT TERM...ROLFSON LONG TERM...TITUS AVIATION...JLB MARINE...TITUS
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
553 AM CST Sun Jan 26 2014 .SHORT TERM: (Through Late This Afternoon) Issued at 310 AM CST Sun Jan 26 2014 Big warm-up on tap for today with well-above average temps. Winds have already swung around to southerly overnight and temps have been slowly creeping upward. The warm front now extending from the surface low in north central Iowa into western MO will surge eastward across the CWA this morning as the surface low moves into the Great Lakes, with winds veering to southwest and then westerly and strong warm advection across the area. I have boosted temps from the previous forecast and am close to the last few hourly runs of the RAP which appear to have a good handle on the current temperatures here and upstream. Highs in most locations should get into the 50s. Enjoy the warmth...it ends tonight! Glass .LONG TERM: (Tonight through Saturday) Issued at 310 AM CST Sun Jan 26 2014 A powerful Arctic cold front will drive like a freight train through the CWA tonight. A strong pressure gradient and large pressure rises behind the front all point to very strong and gusty NW winds with the fropa. Have issued a wind advisory for all but southeast Missouri anticipating a 3-4 period with sustained winds of 25-35 mph and gusts of 45+. In addition to intense cold advection and plummeting temperatures, it appears that strong low level frontogenetic forcing and weak large scale ascent will produce a narrow band of snow immediately in the cold air. The band will be moving so quickly and the wind blowing so hard that any accumulations will be very light. Dangerous wind chills of 15 to 20 below zero are still on target late tonight and into Tuesday morning across northeast MO into central IL due to various combinations of the wind and bitterly cold ambient air temperatures. The previously issued wind chill advisory looks right on target for the anticipated high threat area. The bitterly cold Arctic air mass will dominate the area into Tuesday, and will be the coldest since the early January Arctic Outbreak. During the later half of the week ahead and into next weekend the upper air pattern finally breaks down. The longwave trof which has dominated eastern NOAM for weeks will weaken and shift northeastward as amplfication occurs from the eastern Pacific into the western U.S. and the negative phase of the PNA pattern becomes established. There are some important differences in the deterministic model solutions during this time frame with regards to shortwave features with the developing wsw flow aloft, the location of a baroclinic zone and the depth/magnitude of cold air. This leads to greater uncertainty than normal in the details, however all guidance points to increasing precipitation chances next weekend and potential for wintery precipitation. Glass && .AVIATION: (For the 12z TAFs through 12z Monday Morning) Issued at 552 AM CST Sun Jan 26 2014 As surface low weakens and tracks to the east into the great lakes region, south to southwest winds to pickup near 15kts with gusts to near 25kts at times with just some mid and high clouds. Still experiencing LLWS mainly over KCOU and metro area tafs, so kept mention for a few more hours this morning as winds continue to mix down to the surface. Then gradient weakens by this afternoon ahead of strong arctic front so winds to diminish. Then the cold front to move into KUIN by 02z, KCOU by 03z and metro area by 04z. Winds quickly veer to the northwest to north behind the boundary and pickup with sustained winds near 30kts and gusts near 40kts. Low end vfr cigs to move in with some light snow/snow showers. By late in the forecast period, will see winds diminish just a bit but continue to see gusts near 30kts. Specifics for KSTL: As surface low weakens and tracks to the east into the great lakes region, south to southwest winds to pickup near 15kts with gusts to near 25kts at times with just some mid and high clouds. Still experiencing LLWS over metro area, so kept mention through 15z this morning as winds continue to mix down to the surface. Then gradient weakens by 22z this afternoon ahead of strong arctic front so winds to diminish. Then the cold front to move into metro area by 04z Monday. Winds quickly veer to the northwest to north behind the boundary and pickup with sustained winds near 30kts and gusts near 40kts. Low end vfr cigs to move in with some flurries/snow showers. By 11z Monday, will see winds diminish just a bit but continue to see gusts near 30kts. Byrd && .PRELIMINARY POINT TEMPS/POPS: Saint Louis 56 6 12 0 / 5 30 0 0 Quincy 49 -1 5 -7 / 10 40 0 0 Columbia 56 6 13 -2 / 0 30 0 0 Jefferson City 58 8 14 -1 / 0 30 0 0 Salem 51 6 10 -2 / 5 30 5 0 Farmington 58 10 15 -1 / 0 30 5 0 && .LSX WATCHES/WARNINGS/ADVISORIES: MO...WIND ADVISORY from 8 PM this evening to 6 AM CST Monday FOR Audrain MO-Boone MO-Callaway MO-Cole MO-Franklin MO- Gasconade MO-Jefferson MO-Knox MO-Lewis MO-Lincoln MO- Marion MO-Moniteau MO-Monroe MO-Montgomery MO-Osage MO-Pike MO-Ralls MO-Shelby MO-St. Charles MO-St. Louis City MO-St. Louis MO-Warren MO. WIND CHILL ADVISORY from 3 AM Monday to Noon CST Tuesday FOR Knox MO-Lewis MO-Marion MO-Monroe MO-Pike MO-Ralls MO- Shelby MO. IL...WIND ADVISORY from 8 PM this evening to 6 AM CST Monday FOR Adams IL-Bond IL-Brown IL-Calhoun IL-Clinton IL-Fayette IL- Greene IL-Jersey IL-Macoupin IL-Madison IL-Marion IL-Monroe IL-Montgomery IL-Pike IL-Randolph IL-St. Clair IL- Washington IL. WIND CHILL ADVISORY from 3 AM Monday to Noon CST Tuesday FOR Adams IL-Brown IL-Calhoun IL-Fayette IL-Greene IL-Jersey IL- Macoupin IL-Montgomery IL-Pike IL. && $$ WFO LSX
AREA FORECAST DISCUSSION
NWS HASTINGS NE
520 AM CST SUN JAN 26 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 324 AM CST SUN JAN 26 2014 TURNING WINDY AND SHARPLY COLD DURING THE SHORT TERM PERIODS. THE WEATHER PATTERN WILL BE UNDERGOING CHANGES DURING THE SHORT TERM PERIODS AS ENERGY ROTATES AROUND THE UPPER LOW IN THE VICINITY OF THE HUDSON BAY AND AND SWINGS ACROSS THE INTERIOR CONUS...ALLOWING ARCTIC AIR TO PLUNGE SOUTH ACROSS THE CENTRAL PLAINS THIS AFTERNOON AND TONIGHT. THIS WILL BRING A DRASTIC END TO OUR WARMER TEMPERATURES THE LAST COUPLE OF DAYS AS SHARPLY COLDER AIR ARRIVES ABOARD INTENSE NORTHERLY WINDS. CURRENTLY A SFC LOW PRESSURE SYSTEM WAS SLIDING EAST ACROSS IA EARLY THIS MORNING AND IN STEADY/GUSTY WESTERLY WINDS BEHIND THE SYSTEM TEMPS HAVE REMAINED MILD IN THE 40S AND 50S. AS SOME MID LEVEL WARM AIR HAS MIXED TO THE SFC THE TEMP AT ORD JUMPED TO 53 DEGREES WHICH WILL LIKELY BE THE CALENDAR DAY HIGH FOR THIS AREA TODAY. UPSTREAM...THE ARCTIC AIRMASS WAS ADVANCING SOUTH THRU CANADA TOWARDS THE DAKOTAS. THE MORNING HOURS INTO THE FIRST PART OF THE AFTERNOON WILL CONTINUE TO FEATURE MILD WEATHER WITH STEADY/GUSTY WINDS WITH WINDS TRENDING UP FURTHER BY LATE MORNING AS MIXING INCREASES/DEEPENS. THE AFTERNOON HOURS INTO THE EVENING WILL SEE THE BIGGER WEATHER CHANGES AS THE ARCTIC FRONT MOVES INTO OUR NORTHERN ZONES AROUND 21Z OR SHORTLY THEREAFTER. THE ARCTIC FRONT REACHES THE NEB/KS STATELINE BY 00Z AND CLEARS OUR CWA BY 03Z. TEMPS WILL RAPIDLY FALL IN THE ARCTIC AIRMASS N/S THIS AFTN/EVENING. MODELS CONTINUE TO PROG VERY IMPRESSIVE THREE HOUR PRESSURE RISES BEHIND THE FRONT ON THE ORDER OF 12MB. THE TIGHT PRESSURE GRADIENT...DEEP MIXING AS HIGH AS H8 WILL LEAD TO INTENSE WINDS DEVELOPING MID TO LATE AFTERNOON ACROSS OUR NORTH AND SPREADING SOUTHWARD WITH THE FRONT THIS EVENING AND TONIGHT. GIVEN THE STRONG WINDS/WIND GUSTS WILL GO AHEAD WITH A WIND ADVISORY HEADLINE BEGINNING THIS AFTERNOON AND CONTINUING INTO THE FIRST PART OF THE NIGHT UNTIL THE GRADIENT RELAXES. STILL HAVE CONCERNS FOR REACHING HIGH WIND WARNING ACROSS OUR NORTHEAST ZONES WHERE WINDS AT THE TOP OF THE MIXED LAYER PER RAP SOUNDINGS AVERAGE NEAR 50KTS AND THIS WILL NEED TO BE MONITORED CLOSELY TODAY...AND WIND ADVISORY MAY NEED TO BE UPGRADED TO WARNING IF WINDS TREND UP MUCH FURTHER. HAVE ALSO MAINTAINED AN OUTSIDE CHC FOR SPRINKLES/FLURRIES IN FRONTOGENESIS...BUT DO NOT EXPECT MUCH MORE THAN THAT WITH LLVL MOISTURE LACKING. TONIGHT...A 1040MB SFC RIDGE BUILDS SOUTHEAST FM THE DAKOTAS ONTO THE PLAINS...AND WIND SPEEDS WILL GRADUALLY DECREASE TOWARD MORNING AS THE GRADIENT RELAXES. IN THE ARCTIC AIRMASS TEMPERATURES BOTTOM OUT IN THE SINGLE DIGITS ABOVE/BELOW ZERO. THE COMBINATION OF THE COLD TEMPS IN THE ARCTIC AIR WITH THE STEADY WINDS WILL LEAD TO FRIGID WIND CHILLS AT WIND CHILL ADVISORY CRITERIA ACROSS PORTIONS OF SOUTH CENTRAL NEBRASKA. A WIND CHILL ADVISORY WILL BE POSTED FOR LOCATIONS IN NEBRASKA ALONG/NORTH OF INTERSTATE 80 WHERE THE COLDEST WIND CHILL READINGS ARE EXPECTED FOR THE LONGEST DURATION. IF TEMPS TREND LOWER OR WINDS REMAIN STRONGER FARTHER SOUTH...THIS ADVISORY MAY NEED TO BE EXPANDED. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 324 AM CST SUN JAN 26 2014 MAIN FORECAST CONCERNS WILL BE WIND CHILLS EARLY MONDAY MORNING...CHANCES FOR SNOW WEDNESDAY NIGHT AND AGAIN FRIDAY THROUGH SATURDAY AND TEMPERATURES THROUGH THE PERIOD. WINDS AND COLD TEMPERATURES WILL CONTINUE TO BRING WIND CHILL READINGS DOWN TO AROUND 20 BELOW EARLY MONDAY MORNING. A COLD SURFACE HIGH PRESSURE PUSHES INTO THE CENTRAL PLAINS MONDAY THROUGH TUESDAY. THE CENTER OF THE HIGH SHOULD REMAIN TO THE EAST OF THE FORECAST AREA SO THE WINDS WILL CONTINUE AS WELL AS THE COLD TEMPERATURES. WIND CHILLS WILL BE AROUND 15 BELOW IN THE FAR NORTH AGAIN EARLY TUESDAY MORNING. AS THE SURFACE HIGH MOVES TO THE EAST TUESDAY NIGHT THERE IS WARM ADVECTION ACROSS THE AREA LATE TUESDAY NIGHT INTO WEDNESDAY. TEMPERATURES WILL BE THE WARMEST ON WEDNESDAY. BY WEDNESDAY NIGHT THERE IS AN UPPER LEVEL WAVE THAT MOVES THROUGH THE AREA AS WELL AS ANOTHER COLD FRONT. THERE IS A SLIGHT CHANCE FOR SOME LIGHT SNOW IN THE FAR NORTH AS THIS WAVE MOVES THROUGH. MODELS HAVE A FEW DIFFERENCES FOR THE FRIDAY TO SATURDAY TIME FRAME...BUT BOTH THE GFS AND THE ECMWF HAVE AT LEAST A LITTLE PRECIPITATION ACROSS THE AREA OFF AND ON. ANOTHER UPPER LEVEL WAVE MOVES THROUGH THE AREA AND THIS TIME THERE IS SOME MOISTURE TO WORK WITH. THE GFS HAS A LITTLE MORE PRECIPITATION THAN THE ECMWF...BUT BOTH HAVE A LITTLE. WILL KEEP SLIGHT CHANCES IN FOR FRIDAY THROUGH SATURDAY. TEMPERATURES SHOULD BE A LITTLE BELOW NORMAL AND THE PRECIPITATION SHOULD BE SNOW. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 508 AM CST SUN JAN 26 2014 WIND WILL BE THE MAIN ISSUE DURING THE TAF PERIOD. NORTHWEST WINDS WILL INCREASE DURING THE DAY...WITH THE STRONGEST WINDS ARRIVING BEHIND THE PASSAGE OF AN ARCTIC COLD FRONT DURING THE MID TO LATE AFTERNOON HOURS. WINDS IN EXCESS OF 30KTS AND GUSTS IN EXCESSIVE OF 40KTS ARE EXPECTED. THE WINDS WILL REMAIN STRONG INTO THE FIRST PART OF THE NIGHT BEFORE GRADUALLY SUBSIDING TOWARD MONDAY MORNING AS THE GRADIENT RELAXES. FOR THE MOST PART CLOUDS SHOULD REMAIN AT VFR LEVELS BUT DID INCLUDE SOME SCATTERED MVFR CLOUDS. OTHERWISE THERE IS AN OUTSIDE CHC FOR A SPRINKLE OR FLURRY WITH FROPA BUT NOTHING SUBSTANTIAL ENOUGH TO INSERT IN TAF. && .GID WATCHES/WARNINGS/ADVISORIES... NE...WIND ADVISORY FROM 2 PM THIS AFTERNOON TO MIDNIGHT CST TONIGHT FOR NEZ072>077-082>087. WIND ADVISORY FROM NOON TODAY TO MIDNIGHT CST TONIGHT FOR NEZ039>041-046>049-060>064. WIND CHILL ADVISORY FROM 2 AM TO 10 AM CST MONDAY FOR NEZ039>041- 046>049-060>064. KS...WIND ADVISORY FROM 6 PM THIS EVENING TO 2 AM CST MONDAY FOR KSZ005>007-017>019. && $$ SHORT TERM...FAY LONG TERM...JCB AVIATION...FAY
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
507 AM CST SUN JAN 26 2014 .SHORT TERM...(TODAY THROUGH TUESDAY) ISSUED AT 253 AM CST SUN JAN 26 2014 ...VERY WINDY THIS AFTERNOON AND EVENING THEN BITTER COLD LATE TONIGHT AND EARLY MONDAY... FAIRLY COMPLEX FORECAST SETTING UP THROUGH THE SHORT TERM AS THE NEXT IN A SERIES OF ARCTIC FRONTS SWEEPS ACROSS THE REGION THIS AFTERNOON. THE CLIPPER SYSTEM THAT MOVED TO OUR NORTH AND EAST EARLIER THIS MORNING HAS LEFT US WITHIN A VERY MILD REGIME WITH TEMPS EARLY THIS MORNING SIGNIFICANTLY WARMER THAN PREVIOUSLY THOUGHT IN THE 40S TO NEAR 50. WHILE TEMPS WILL COOL A BIT THROUGH DAYBREAK...IT`S GOING TO BE ON THE MILD SIDE AHEAD OF THE ARCTIC FRONT. ARRIVAL OF ARCTIC FRONT IS STILL ON SCHEDULE...MOVING INTO NORTHEAST NEBRASKA 18-21Z...AND THE REMAINDER OF THE REGION 21-00Z. HAVE NO DOUBT WE`LL MEET WIND ADVISORY CRITERIA TODAY...THE BIG QUESTION IS IF WIND GUSTS WILL BE STRONG ENOUGH TO MEET HIGH WIND WARNING CRITERIA...AS THEY HAVE WITH SEVERAL PREVIOUS FRONTS OVER THE LAST COUPLE OF WEEKS. SOUNDINGS STILL SUGGEST THAT WE`LL MIX VERY DEEP WITH THE ARRIVAL OF THE ARCTIC AIR UP TO 750/725 MB. WINDS AT THIS LEVEL WILL BE QUITE STRONG AT 60 TO 70 KNOTS. NAM AND RAP ARE THE MOST AGGRESSIVE WITH THE WIND GUST POTENTIAL BOTH SUGGESTING THAT SURFACE WINDS COULD GUST TO 50 KNOTS OR SLIGHTLY HIGHER. OTHER MODEL SUITES AREN`T QUITE AS STRONG. COMPOUNDING THE ARRIVAL OF THE WINDS...THERE COULD BE SCATTERED SHOWERS THAT DEVELOP...INITIALLY RAIN AND THEN SNOW...WHICH WILL HELP WITH MOMENTUM TRANSFER TO THE SURFACE. NAM DOESN`T DEVELOP MUCH PRECIPITATION...BUT NEARLY ALL OTHER MODEL SUITES DO. THERE IS SOME CONCERN THAT A CONVECTIVE SNOW BAND COULD DEVELOP WITH THE SURGE OF COLDER AIR...ESPECIALLY SHOWN BY 03Z HOPWRF RUNS. WILL HAVE TO MONITOR FOR ANY VISIBILITY DROPS ONCE THE PRECIP CHANGES TO SNOW AS WELL...AND WHETHER THERE COULD BE THE POTENTIAL FOR A QUICK HALF INCH OF SNOW IN NORTHEAST NEBRASKA AND WESTERN IOWA. HAVE OPTED TO CONVERT THE HIGH WIND WATCH INTO A HIGH WIND WARNING ALONG AND NORTH OF I80. STRONG WINDS CONTINUE INTO SUNDAY EVENING...THUS WILL HAVE AN ADVISORY FOR THE REMAINING COUNTIES... WHERE MOMENTUM MIXING MAY NOT BE AS STRONG SINCE THE SUN WILL HAVE SET BY THEN. HIGH WIND WARNING COULD EVENTUALLY BE CONVERTED INTO A WIND ADVISORY AS SEVERE GUST POTENTIAL SUBSIDES THROUGH THE EVENING...BUT WOULD BEST BE MANAGED IN THE VERY NEAR TERM WITH UPDATES BASED ON REAL TIME REPORTS. SECONDARY IMMEDIATE CONCERN FOR LATER SUNDAY NIGHT INTO EARLY MONDAY IS THE ARRIVAL OF VERY COLD TEMPS BEHIND THE ARCTIC FRONT. READINGS SHOULD DROP INTO THE SINGLE DIGITS ABOVE AND BELOW ZERO...SIMILAR TO THE ARCTIC SURGE OF LAST WEEK. WHEN COUPLED WITH WINDS STILL IN THE 10-15 MPH RANGE...THIS WILL PRODUCE WIND CHILL VALUES OF 20 TO 29 BELOW THROUGH MONDAY MORNING ALONG AND NORTH OF I80 AND ACROSS MOST OF SOUTHWEST IOWA. THUS WILL HAVE A WIND CHILL ADVISORY IN EFFECT. SURFACE HIGH PRESSURE RIDGE REMAINS ACROSS THE REGION THROUGH TUESDAY. THIS WILL RESULT IN A VERY COLD DAY MONDAY...AND SUB ZERO READINGS AGAIN MONDAY NIGHT. WINDS WILL BE LIGHTER THAN MONDAY MORNING...BUT BECAUSE IT`S COLDER...WIND CHILL VALUES WILL AGAIN DROP TO 20 TO 28 BELOW OVER SOME PARTS OF THE FORECAST AREA. STILL A COLD DAY TUESDAY. .LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY) ISSUED AT 253 AM CST SUN JAN 26 2014 FORECAST PROBLEMS WITH THE EXTENDED INVOLVE ANOTHER FRONT THAT MOVES THROUGH THE REGION WEDNESDAY NIGHT. AHEAD OF THE FRONT...DECENT POTENTIAL TO WARM BACK INTO THE 30S...THEN COLDER BEHIND IT ON THURSDAY. STILL LOOKS LIKE A SMALL CHANCE OF LIGHT SNOW WEDNESDAY NIGHT. AND STILL SOME SMALL POTENTIAL THAT IT COULD LINGER INTO THURSDAY MORNING...BUT WILL WAIT FOR ANOTHER SET OF MODEL RUNS TO FINE TUNE THAT. BIGGER CONCERN IS SETTING UP FOR FRIDAY AND SATURDAY. THE GFS IS PAINTING A FAIRLY ROBUST WAVE MOVING OUT OF THE ROCKIES GIVING US A PRETTY CHANCE OF SNOW. THE ECMWF ALSO HAVE A WAVE...BUT IS A LITTLE BIT SLOWER AND WOULD HOLD OFF UNTIL FRIDAY NIGHT. AGAIN... WILL NEED TO WAIT FOR ANOTHER DAY OF MODEL RUNS TO FINE TUNE THIS...BUT IT APPEARS THAT SNOW CHANCES MAY BE INCREASING LATE IN THE WEEK. && .AVIATION...(12Z TAFS FOR KOFK...KLNK AND KOMA.) ISSUED AT 505 AM CST SUN JAN 26 2014 STRONG WINDS AND THE POTENTIAL FOR RAINSHOWERS/SNOWSHOWERS WILL BE THE PRIMARY AVIATION CONCERNS TODAY. SURFACE LOW PRESSURE IS QUICKLY SHIFTING OFF TO THE EAST AND HAVE SEEN AN INCREASE IN NORTHWEST WINDS BEHIND THIS FEATURE ALONG WITH SOME PATCHY CLOUDS...GENERALLY FL040 TO FL100. THIS MORNING...THE WINDS ALOFT WEAKEN SLIGHTLY AHEAD OF THE SURGE OF COLD AIR THIS AFTERNOON....THUS WINDS WILL BE MORE IN THE 10 TO 20KT RANGE. SURFACE WINDS INCREASE INTO THE 25 TO 35KT WITH GUSTS 40-50KT AFTER 17-18Z AT KOFK AND REACHING KOMA AND KLNK 20-22Z. RAINSHOWERS/SNOWSHOWERS SHOULD ACCOMPANY THE SURGE OF COLD AIR...THUS WILL MENTION IN THE TAFS BETWEEN NOON AND 3PM AT KOFK AND 2PM-5PM AT KOMA/KLNK. VSBYS MAY DROP SIGNIFICANTLY WITH THE FALLING SNOW AND WIND. DUE TO SOME TIMING DIFFERENCES...THIS CAN BE REFINED AS THE PRECIPITATION DEVELOPS. ALSO THERE IS SOME INSTABILITY...SO WILL NEED TO BE ALERT TO THIS. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...HIGH WIND WARNING FROM 3 PM THIS AFTERNOON TO MIDNIGHT CST TONIGHT FOR NEZ034-044-045-050>053-065>067. WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO 10 AM CST MONDAY FOR NEZ011-012-015>018-031>034. WIND ADVISORY FROM 5 PM THIS AFTERNOON TO MIDNIGHT CST TONIGHT FOR NEZ078-088>090-092. HIGH WIND WARNING FROM 5 PM THIS AFTERNOON TO MIDNIGHT CST TONIGHT FOR NEZ068-091-093. WIND CHILL ADVISORY FROM 3 AM TO 10 AM CST MONDAY FOR NEZ030- 042>045-050>053-065>068. HIGH WIND WARNING FROM NOON TODAY TO MIDNIGHT CST TONIGHT FOR NEZ011-012-015>018-030>033-042-043. IA...HIGH WIND WARNING FROM 3 PM THIS AFTERNOON TO MIDNIGHT CST TONIGHT FOR IAZ043-055-056-069-079-080. WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO 10 AM CST MONDAY FOR IAZ043-055-056. HIGH WIND WARNING FROM 5 PM THIS AFTERNOON TO MIDNIGHT CST TONIGHT FOR IAZ090-091. WIND CHILL ADVISORY FROM 3 AM TO 10 AM CST MONDAY FOR IAZ069-079- 080-090-091. && $$ SHORT TERM...DEWALD LONG TERM...DEWALD AVIATION...ZAPOTOCNY
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
418 PM CST SUN JAN 26 2014 .DISCUSSION... 255 PM CST THE CONCERNS WITH PREVIOUS FORECAST CYCLES CONTINUE THIS AFTERNOON...WITH THE PRIMARY EMPHASIS BEING SNOW AND BLOWING SNOW THIS EVE...BLOWING SNOW OVERNIGHT INTO MONDAY...AND BITTER COLD LATE TONIGHT THROUGH WEDNESDAY MORNING. THE PRIMARY HEADLINE CHANGE WAS TO UPGRADE NORTH CENTRAL IL TO A WINTER STORM WARNING FOR TONIGHT. IN COLLABORATION WITH ADJACENT WFOS...BELIEVE THAT THE COMBINATION OF SNOW AND BLOWING SNOW THIS EVE...ALONG WITH THE SUBSEQUENT BLOWING SNOW OVERNIGHT...IS ENOUGH TO WARRANT A WARNING. TEMPORARY BLIZZARD CONDITIONS CAN CERTAINLY BE HANDLED WITH AN ADVISORY...BUT WE /DVN..MKX...AND LOT/ FEEL THIS IS ENOUGH OF A CONCERN FOR NORTH CENTRAL IL AND ADJACENT NORTH AND WEST LOCALES TO HIGHLIGHT MORE SO WITH A WARNING. THE IMPRESSIVE UPPER TROUGH CONTINUES TO DIG EAST SOUTHEAST ACROSS THE UPPER MIDWEST. THE SURFACE ARCTIC FRONT LIES FROM NORTHERN WI SOUTHEAST THROUGH WESTERN IA AS OF 230 PM. WIND GUSTS BEHIND THIS FRONT OF 40 TO 50 KT EXIST WITHIN THE TIGHT PRESSURE GRADIENT ALL THE WAY BACK TO THE INTERNATIONAL BORDER ACROSS WESTERN MN AND THE DAKOTAS. THE RADAR MOSAIC INDICATES SNOW INCREASING IN COVERAGE WITHIN THE FORCING AHEAD OF THE UPPER TROUGH...WITH THE NATURE BEING MAINLY SNOW SHOWERISH THUS FAR. A CONTINUED UPTICK IN COVERAGE SHOULD BE SEEN THROUGH EARLY EVENING AS THIS SPREADS INTO THE FORECAST AREA. THE RAP AND LOCAL 8KM ARW BOTH SEEM TO BE HANDLING THE ONGOING PRESSURE PATTERN WELL...AND BASICALLY EVOLVE A SURFACE LOW ALONG THE BOUNDARY ACROSS THE FORECAST AREA. THIS LOOKS TO BE IN RESPONSE TO THE INCREDIBLY STRONG UPPER AND MID-LEVEL FORCING FOR ASCENT...ALONG WITH THE PRONOUNCED BAROCLINICITY WITH 40 DEGREES UP TO THE FAR SOUTHERN FORECAST AREA AND SUBZERO AIR QUICKLY HEADED SOUTH BEHIND THE BOUNDARY. AS THIS LOW DEVELOPS...A RESPONSIVE INCREASE IN MID TO LOW-LEVEL FRONTOGENESIS IS FORECAST BY THE RAP AND ARW BY 6-7 PM IN NORTHERN IL. THIS QUICKLY EVOLVES EAST ACROSS THE FORECAST AREA THROUGH ABOUT 10 PM. THERE CONTINUES TO BE INSTABILITY ABOVE THIS FORCING AND IN A SATURATED LAYER TO SUPPORT A QUICK BURST OF MODERATE SNOW/SNOW SHOWERS. THIS MAY PRODUCE 1-2 INCHES IN JUST THE 1-2 HR WINDOW IN WHICH IT LASTS IN ANY ONE LOCATION. THE TIMING OF THE PRECIP LOOKS TO LINE UP WITH THE ARCTIC FRONT PASSAGE...AND THAT PASSAGE SIGNALS THE RAPID INCREASE IN WIND SPEED THAT IS OCCURRING UPSTREAM. GUSTS LOOK TO BE 40-50 MPH FOR A FEW HOUR WINDOW IMMEDIATELY BEHIND THE FRONT USING TOP OF THE CHANNEL MIXING WHICH SHOULD BE SUPPORTED IN THAT IMMEDIATE FROPA ATMOSPHERE. THESE GUSTS SHOULD EASE GRADUALLY TO 30-35 MPH THE REMAINDER OF THE NIGHT. WHILE THE WARM TEMPS TODAY MAY HAVE INCREASED THE SNOW DENSITY SOME...WET BULB VALUES REMAINING BELOW FREEZING HAVE LIKELY LIMITED MUCH FOR MELTING. THESE FORECAST WIND SPEEDS THUS ARE MORE THAN ENOUGH TO CREATE SIGNIFICANT ISSUES WITH BLOWING AND DRIFTING SNOW. THOSE FEW HOURS OF FALLING SNOW WITH THE MAXIMA OF GUSTS ARE THE PRIMARY REASON FOR THE WARNING...BUT WITH HIGH CONFIDENCE IN BLOWING AND DRIFTING SNOW CONTINUING THROUGH THE NIGHT ADDS FURTHER TO THE NEED TO UPGRADE TO A WARNING. WITH 27 OF 50 DAYS HAVING MEASURABLE SNOW IN CHICAGO AND ROCKFORD...SOMETHING THAT HAS ONLY HAPPENED A HANDFUL OF TIMES IN THEIR LONG RECORD OF HISTORY...WE ACTUALLY WILL OBSERVE A TWO DAY BREAK IN SNOWFALL ON MONDAY AND TUESDAY. HOWEVER AS THIS WINTER GOES...THE CONCERN JUST SHIFTS TO ANOTHER WINTER ELEMENT...AND THAT IS THE COLD. TEMPERATURES SHOULD DROP QUICKLY THIS EVE...WHICH WILL LIKELY CREATE FLASH FREEZING CONDITIONS ON UNTREATED ROADWAYS...AND EVEN TREATED ONES MAY STRUGGLE DUE TO BLOWING SNOW AND THE DEGREE IN WHICH TEMPS DROP. READINGS SHOULD CONTINUE TO FALL THROUGH MID TO LATE MORNING GIVEN THE STRONG CAA. THESE LOOK TO LEVEL OUT OR CLIMB A COUPLE DEGREES MONDAY AFTERNOON BUT THAT WILL BE IT...WITH LOCATIONS HAVING DAYTIME HIGHS OF 4 TO 8 BELOW. WIND CHILLS RIGHT NOW ARE FORECAST AT 30 TO 40 BELOW ACROSS MUCH OF THE FORECAST AREA FROM LATE TONIGHT THROUGH MONDAY. BLOWING SNOW WILL LIKELY CONTINUE IN OUTLYING AREAS ON MONDAY AND HAVE CONTINUED THAT IN THE FORECAST. WILL LIKELY TRANSITION TO MENTIONING THAT WITHIN THE WIND CHILL WARNING AFTER THE CURRENT WINTER STORM WARNING/ADVISORY END MONDAY MORNING. MTF MONDAY NIGHT THROUGH THE LONG TERM (THURSDAY THROUGH SATURDAY)... THE LARGE SCALE TROUGH CONTINUES TO ROTATE OVER THE REGION...AND THE FINAL TROUGH AXIS ROTATES THROUGH TUESDAY EVENING AND NIGHT BEFORE THE TROUGH FINALLY HIGH TAILS IT OUT OF HERE. WEAK RIDGING ALOFT OCCURS WEDNESDAY THEN AN UPPER LEVEL LOW AND WEAK VORT STREAMER SWING THROUGH THURSDAY. ZONAL FLOW THURSDAY NIGHT TRANSITIONS TO WEAK RIDGING LATE ON FRIDAY. AT THE SURFACE HIGH PRESSURE CONTINUES DOWN THE PLAINS AND PASSES OVER THE CENTRAL MISSISSIPPI VALLEY TUESDAY AFTERNOON BEFORE REACHING THE SE US LATE WEDNESDAY. MEANWHILE...LOW PRESSURE DROPS OVER SASKATCHEWAN TUESDAY AFTERNOON AND HOOKS TO THE NE OVER ONTARIO LATE WEDNESDAY. THE LOWS COLD FRONT PASSES THROUGH THE REGION THURSDAY WITH THE GFS A BIT FASTER WITH THE FROPA THAN THE ECMWF. HIGH PRESSURE BUILDS DOWN THE PLAINS THURSDAY...BUT THIS TIME IT LOOKS AS IF IT WILL PASS OVER THE REGION FRIDAY. WHILE JUST ABOUT A WEEK AWAY...GUIDANCE HINTS AT A FRONT/UPPER LEVEL VORT STREAMER PUSHING NORTH AND POSSIBLY CREATING PRECIP FRIDAY. THE REGION REMAINS DRY...EXCEPT FOR LAKE EFFECT SNOW OVER THE EASTERN HALF OF THE LAKE...THROUGH WEDNESDAY. SNOW IS EXPECTED ALONG THE COLD FRONT MID WEEK. KEPT THE CHANCE OF PRECIP FOR FRIDAY INTO SATURDAY AS THE FRONT/UPPER LEVEL VORT STREAMER TRANSITION THROUGH THE REGION. BUT...GUIDANCE HAS BACKED OFF ON THE FORCING AND MOISTURE WITH THIS FEATURE SO HAVE LOWERED POPS A BIT. THE JET LIFTS TO THE NORTH A SMIDGE SATURDAY SO MAY SEE TEMPS IN THE FAR SOUTHERN AREAS GET CLOSE TO FREEZING SATURDAY. THAT BEING SAID KEPT SNOW FOR EVERYONE. FOR TEMPS...RELIEF FROM THE COLD IS IN STORE FOR THOSE WHO ARE PATIENT. MONDAY NIGHT STILL LOOKS BITTERLY COLD AND THE GOING FORECAST LOOKED VERY REASONABLE SO DID NOT MAKE ANY CHANGES TO THE TEMPS. WINDS CONTINUE TO LOOK LIGHTER THAN PREVIOUSLY THOUGHT...WHICH LEADS TO MIN WIND CHILLS BETWEEN -30 AND -45F. FOR REFERENCE MIN 925MB TEMPS WILL BE -24 TO -26C MONDAY EVENING AND ACTUALLY RISE SLOWLY OVERNIGHT TO AROUND -22C BY MORNING. DESPITE THE RISING TEMPS ALOFT...SKIES SHOULD BE RATHER CLEAR ALLOWING AMPLE COOLING OVERNIGHT. THINKING TEMPS WILL ACTUALLY DROP BY A COUPLE OF DEGREES BY DAYBREAK BEFORE RISING TO AROUND 0F TUESDAY. WE DROP BACK BELOW ZERO TUESDAY NIGHT WITH LOWS OF -5 TO -15F AND MIN WIND CHILLS OF -15 TO -30F. BUT HAVE NO FEAR...THE WARM UP BEGINS WEDNESDAY WITH WAA RESULTING IN MAX TEMPS AROUND 20. COULD ACTUALLY BE A DEGREE OR TWO WARMER THAN FORECAST. WENT ON THE CONSERVATIVE SIDE AS I AM NOT SURE HOW WELL WARMING ALOFT WILL MIX TO THE SURFACE. GUSTS UP TO 25 MPH WILL CREATE WIND CHILLS AROUND ZERO WEDNESDAY AFTERNOON. THURSDAY ALSO LOOKS JUST BELOW NORMAL THURSDAY BEFORE THE NEXT WAVE OF COLD AIR PUSHES IN BEHIND THE COLD FRONT THURSDAY. LOWS DROP OFF TO +5 TO -5F THURSDAY NIGHT BUT TEMPS REBOUND LATE NEXT WEEK WITH NEAR NORMAL TEMPS PSBL BY SATURDAY. JEE && .CLIMATE... DAILY TEMPERATURE RECORDS: CHICAGO ROCKFORD JAN 27... RECORD LOW MIN TEMP -10 -13 RECORD LOW MAX TEMP -1 -2 JAN 28... RECORD LOW MIN TEMP -13 -22 RECORD LOW MAX TEMP -3 -5 JAN 29... RECORD LOW MIN TEMP -16 -20 RECORD LOW MAX TEMP -6 -9 DEUBELBEISS && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 22Z... * WEST WINDS GUSTING NEAR 30 KT...SHIFTING WEST-NORTHWEST BY EARLY EVENING WITH POTENTIAL FOR SOME 35-40 KT GUSTS. WINDS BEGIN TO VERY SLOWLY DIMINISH MIDNIGHT AND AFTER. * SCATTERED SNOW SHOWERS DEVELOPING BY EARLY EVENING BEHIND COLD FRONT...LASTING 2-3 HOURS. SOME PATCHY LIFR CONDITIONS POSSIBLE IN STRONGEST SNOW SHOWERS WITH VIS BRIEFLY LESS THAN 1SM AND CIGS OR VV BRIEFLY BELOW 1000 FT. * GUSTY WEST-NORTHWEST WINDS WILL LIKELY RESULT IN BLOWING SNOW WHICH MAY PRODUCE VISIBILITY RESTRICTION AND CONTAMINATION OF PLOWED SURFACES OVERNIGHT. * SCT-BKN MVFR CIGS POSSIBLE INTO MONDAY...WITH GUSTY WEST- NORTHWEST WINDS GRADUALLY DIMINISHING TO 20-25 KTS. RATZER //DISCUSSION...UPDATED 18Z... VERY HAZARDOUS AVIATION CONDITIONS SETTING UP FOR THIS EVENING THROUGH THE OVERNIGHT HOURS. ACRTIC FRONTAL BOUNDARY CONTINUES TO BE THE FOCUS...WITH RESPECT TO TIMING. WINDS HAVE SHIFTED TO THE WEST AND BEGAN TO GUSTS AT TIMES TO ARND 20-25KT. CIGS HAVE BEGUN TO LOWER AS WELL...NEARING MVFR CONDS. WITH THE POWDERY NATURE OF THE SNOWFALL FROM EARLIER THIS MORNING...THE GUSTS WILL EASILY PRODUCE BLOWING SNOW AND LOWER VSBYS BRIEFLY. HOWEVER IT APPEARS CONDS WILL BE MUCH LOWER ONCE THE ARCTIC BOUNDARY ARRIVES ARND 1-2Z...AND WILL BRING VSBYS DOWN FURTHER WITH A BURST OF LIGHT SNOW AND BLOWING SNOW. POSSIBLY SEE VSBYS DOWN TO 1/4 TO 1/2 MILE WITHIN THIS BURST. WINDS WILL RAPIDLY RAMP UP TO GUSTS NEARING 36KT AT THE ONSET. THEN GUSTS WILL RISE EVEN HIGHER NEARING 40KT BY 3Z. CURRENTLY HAVE INDICATED VSBYS MAY IMPROVE A LITTLE AT 3Z...HOWEVER CONFIDENCE IS LOW GIVEN THE POTENTIAL FOR VERY GUSTY WINDS PERSISTING AND LIKELY CAUSING CONTINUED BLOWING SNOW. GUIDANCE INDICATES GUSTS MAY BEGIN TO COME DOWN SLIGHTLY BY 9Z...WITH CIGS HOVERING ARND HIGH END MVFR AND LOW END VFR THRU DAYBREAK. THEN A STRONG PUSH OF DRY AIR SHOULD BRING PARTIAL CLEARING TO THE CLOUDS...HOWEVER THIS MAY ONLY BE TEMPORARY AND A CLOUD DECK APPEARS TO BE POISED TO REDEVELOP LATE MON MORNING. WINDS REMAINING GUSTY AT TIMES FROM THE NORTHWEST BUT NOT AS STRONG AT 20-26KT. BEACHLER //ORD AND MDW CONFIDENCE...UPDATED 22Z... * HIGH CONFIDENCE IN WIND TRENDS...MEDIUM-HIGH CONFIDENCE IN GUST MAGNITUDES THIS EVENING. * MEDIUM-HIGH CONFIDENCE IN SNOW SHOWER TIMING/IMPACTS...EXCEPT LOW CONFIDENCE IN ANY PROLONGED LIFR VSBYS. * MEDIUM CONFIDENCE IN VSBYS IN BLOWING SNOW OVERNIGHT. * HIGH CONFIDENCE IN SCT-BKN STRATOCU DECK MID-RANGE MVFR OR HIGHER LATER TONIGHT THROUGH MONDAY. RATZER //OUTLOOK FOR ORD/MDW FOR 00Z TUESDAY-12Z SUNDAY...UPDATED 12Z... MONDAY NIGHT...VFR. TUESDAY...VFR. WEDNESDAY...VFR. THURSDAY...CHANCE OF SNOW AND IFR. FRIDAY...CHANCE OF SNOW AND IFR FRIDAY EVENING. SATURDAY...CHANCE OF SNOW AND IFR. RC && .MARINE... 151 PM CST WITH HIGH PRESSURE LINGERING ACROSS THE REGION EARLIER THIS MORNING...RELATIVELY LIGHTER SPEEDS WERE OBSERVED EARLIER TODAY. ALTHOUGH...A QUICKLY APPROACHING AREA OF LOW PRESSURE AND ASSOCIATED BOUNDARY HAS SINCE CHANGED THESE CONDITIONS...AND REPLACED THEM WITH AN INCREASING WIND FIELD OVER THE ENTIRE LAKE. 20 TO 30 KT WINDS CONTINUE TO BE OBSERVED PRIMARILY OVER THE NEARSHORE AND SOUTHERN HALF OF THE LAKE...BUT WITH THIS QUICKLY CHANGING AS SPEEDS ARE CURRENTLY INCREASING OVER THE NORTHERN HALF. LOW PRESSURE WILL SLOWLY MOVE EAST ACROSS THE GREAT LAKES REGION THIS AFTERNOON THROUGH TONIGHT WITH A STRONG COLD FRONT MOVING ACROSS THE LAKE THIS EVENING. AS THIS OCCURS...WINDS WILL TURN TO THE NORTHWEST WHILE RAPIDLY INCREASING WITH GALES QUICKLY BEING OBSERVED OVER THE ENTIRE LAKE AND NEARSHORE BY LATE THIS AFTERNOON AND EARLY EVENING. NORTHWEST GALES CAN EXPECTED TONIGHT THROUGH MONDAY MORNING...WITH GALE FORCE GUSTS LINGERING INTO THE REST OF THE DAY MONDAY. ITS EVEN POSSIBLE THAT PREVAILING GALES COULD LINGER SOMEWHAT LONGER THAN THE CURRENT GALE WARNING THROUGH MID MORNING MONDAY...BUT WITH CONFIDENCE LOW WITH REGARDS TO THE POSSIBILITY...HAVE DECIDED TO LEAVE THE CURRENT HEADLINE END TIME AND JUST MENTION GALE FORCE GUSTS. A PERIOD OF ELEVATED WESTERLY WINDS WILL CONTINUE THROUGH THE MIDDLE PORTION OF THE WEEK BEFORE WINDS TURN MORE SOUTHERLY BUT ALSO INCREASE ONCE AGAIN. RODRIGUEZ && .LOT WATCHES/WARNINGS/ADVISORIES... IL...WINTER STORM WARNING...ILZ003-ILZ004-ILZ008-ILZ010-ILZ011-ILZ019- ILZ020-ILZ021-ILZ032 UNTIL 6 AM MONDAY. WIND CHILL WARNING...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010- ILZ011-ILZ012-ILZ013-ILZ014-ILZ020-ILZ022-ILZ023...3 AM MONDAY TO 9 AM WEDNESDAY. WIND CHILL WARNING...ILZ019-ILZ021-ILZ032-ILZ033-ILZ039...3 AM MONDAY TO NOON TUESDAY. WINTER WEATHER ADVISORY...ILZ005-ILZ006-ILZ012-ILZ013-ILZ014- ILZ022-ILZ023-ILZ033-ILZ039 UNTIL 6 AM MONDAY. IN...WIND CHILL WARNING...INZ001-INZ002-INZ010-INZ011...3 AM MONDAY TO 9 AM WEDNESDAY. WINTER WEATHER ADVISORY...INZ001-INZ002-INZ010-INZ011-INZ019 UNTIL 6 AM MONDAY. WIND CHILL WARNING...INZ019...3 AM MONDAY TO NOON TUESDAY. LM...GALE WARNING...LMZ080-LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ740- LMZ741-LMZ742-LMZ743-LMZ744-LMZ745-LMZ777-LMZ779-LMZ868- LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 9 AM MONDAY. HEAVY FREEZING SPRAY WARNING...LMZ080-LMZ261-LMZ362-LMZ364- LMZ366-LMZ563-LMZ565-LMZ567-LMZ669-LMZ671-LMZ673-LMZ675- LMZ777-LMZ779-LMZ868-LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 4 AM WEDNESDAY. GALE WARNING...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565 UNTIL 9 AM MONDAY. HEAVY FREEZING SPRAY WARNING...LMZ740-LMZ741-LMZ742-LMZ743- NEARSHORE GARY TO MICHIGAN CITY IN UNTIL 10 PM MONDAY. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
256 PM CST SUN JAN 26 2014 .DISCUSSION... 255 PM CST THE CONCERNS WITH PREVIOUS FORECAST CYCLES CONTINUE THIS AFTERNOON...WITH THE PRIMARY EMPHASIS BEING SNOW AND BLOWING SNOW THIS EVE...BLOWING SNOW OVERNIGHT INTO MONDAY...AND BITTER COLD LATE TONIGHT THROUGH WEDNESDAY MORNING. THE PRIMARY HEADLINE CHANGE WAS TO UPGRADE NORTH CENTRAL IL TO A WINTER STORM WARNING FOR TONIGHT. IN COLLABORATION WITH ADJACENT WFOS...BELIEVE THAT THE COMBINATION OF SNOW AND BLOWING SNOW THIS EVE...ALONG WITH THE SUBSEQUENT BLOWING SNOW OVERNIGHT...IS ENOUGH TO WARRANT A WARNING. TEMPORARY BLIZZARD CONDITIONS CAN CERTAINLY BE HANDLED WITH AN ADVISORY...BUT WE /DVN..MKX...AND LOT/ FEEL THIS IS ENOUGH OF A CONCERN FOR NORTH CENTRAL IL AND ADJACENT NORTH AND WEST LOCALES TO HIGHLIGHT MORE SO WITH A WARNING. THE IMPRESSIVE UPPER TROUGH CONTINUES TO DIG EAST SOUTHEAST ACROSS THE UPPER MIDWEST. THE SURFACE ARCTIC FRONT LIES FROM NORTHERN WI SOUTHEAST THROUGH WESTERN IA AS OF 230 PM. WIND GUSTS BEHIND THIS FRONT OF 40 TO 50 KT EXIST WITHIN THE TIGHT PRESSURE GRADIENT ALL THE WAY BACK TO THE INTERNATIONAL BORDER ACROSS WESTERN MN AND THE DAKOTAS. THE RADAR MOSAIC INDICATES SNOW INCREASING IN COVERAGE WITHIN THE FORCING AHEAD OF THE UPPER TROUGH...WITH THE NATURE BEING MAINLY SNOW SHOWERISH THUS FAR. A CONTINUED UPTICK IN COVERAGE SHOULD BE SEEN THROUGH EARLY EVENING AS THIS SPREADS INTO THE FORECAST AREA. THE RAP AND LOCAL 8KM ARW BOTH SEEM TO BE HANDLING THE ONGOING PRESSURE PATTERN WELL...AND BASICALLY EVOLVE A SURFACE LOW ALONG THE BOUNDARY ACROSS THE FORECAST AREA. THIS LOOKS TO BE IN RESPONSE TO THE INCREDIBLY STRONG UPPER AND MID-LEVEL FORCING FOR ASCENT...ALONG WITH THE PRONOUNCED BAROCLINICITY WITH 40 DEGREES UP TO THE FAR SOUTHERN FORECAST AREA AND SUBZERO AIR QUICKLY HEADED SOUTH BEHIND THE BOUNDARY. AS THIS LOW DEVELOPS...A RESPONSIVE INCREASE IN MID TO LOW-LEVEL FRONTOGENESIS IS FORECAST BY THE RAP AND ARW BY 6-7 PM IN NORTHERN IL. THIS QUICKLY EVOLVES EAST ACROSS THE FORECAST AREA THROUGH ABOUT 10 PM. THERE CONTINUES TO BE INSTABILITY ABOVE THIS FORCING AND IN A SATURATED LAYER TO SUPPORT A QUICK BURST OF MODERATE SNOW/SNOW SHOWERS. THIS MAY PRODUCE 1-2 INCHES IN JUST THE 1-2 HR WINDOW IN WHICH IT LASTS IN ANY ONE LOCATION. THE TIMING OF THE PRECIP LOOKS TO LINE UP WITH THE ARCTIC FRONT PASSAGE...AND THAT PASSAGE SIGNALS THE RAPID INCREASE IN WIND SPEED THAT IS OCCURRING UPSTREAM. GUSTS LOOK TO BE 40-50 MPH FOR A FEW HOUR WINDOW IMMEDIATELY BEHIND THE FRONT USING TOP OF THE CHANNEL MIXING WHICH SHOULD BE SUPPORTED IN THAT IMMEDIATE FROPA ATMOSPHERE. THESE GUSTS SHOULD EASE GRADUALLY TO 30-35 MPH THE REMAINDER OF THE NIGHT. WHILE THE WARM TEMPS TODAY MAY HAVE INCREASED THE SNOW DENSITY SOME...WET BULB VALUES REMAINING BELOW FREEZING HAVE LIKELY LIMITED MUCH FOR MELTING. THESE FORECAST WIND SPEEDS THUS ARE MORE THAN ENOUGH TO CREATE SIGNIFICANT ISSUES WITH BLOWING AND DRIFTING SNOW. THOSE FEW HOURS OF FALLING SNOW WITH THE MAXIMA OF GUSTS ARE THE PRIMARY REASON FOR THE WARNING...BUT WITH HIGH CONFIDENCE IN BLOWING AND DRIFTING SNOW CONTINUING THROUGH THE NIGHT ADDS FURTHER TO THE NEED TO UPGRADE TO A WARNING. WITH 27 OF 50 DAYS HAVING MEASURABLE SNOW IN CHICAGO AND ROCKFORD...SOMETHING THAT HAS ONLY HAPPENED A HANDFUL OF TIMES IN THEIR LONG RECORD OF HISTORY...WE ACTUALLY WILL OBSERVE A TWO DAY BREAK IN SNOWFALL ON MONDAY AND TUESDAY. HOWEVER AS THIS WINTER GOES...THE CONCERN JUST SHIFTS TO ANOTHER WINTER ELEMENT...AND THAT IS THE COLD. TEMPERATURES SHOULD DROP QUICKLY THIS EVE...WHICH WILL LIKELY CREATE FLASH FREEZING CONDITIONS ON UNTREATED ROADWAYS...AND EVEN TREATED ONES MAY STRUGGLE DUE TO BLOWING SNOW AND THE DEGREE IN WHICH TEMPS DROP. READINGS SHOULD CONTINUE TO FALL THROUGH MID TO LATE MORNING GIVEN THE STRONG CAA. THESE LOOK TO LEVEL OUT OR CLIMB A COUPLE DEGREES MONDAY AFTERNOON BUT THAT WILL BE IT...WITH LOCATIONS HAVING DAYTIME HIGHS OF 4 TO 8 BELOW. WIND CHILLS RIGHT NOW ARE FORECAST AT 30 TO 40 BELOW ACROSS MUCH OF THE FORECAST AREA FROM LATE TONIGHT THROUGH MONDAY. BLOWING SNOW WILL LIKELY CONTINUE IN OUTLYING AREAS ON MONDAY AND HAVE CONTINUED THAT IN THE FORECAST. WILL LIKELY TRANSITION TO MENTIONING THAT WITHIN THE WIND CHILL WARNING AFTER THE CURRENT WINTER STORM WARNING/ADVISORY END MONDAY MORNING. MTF MONDAY NIGHT THROUGH THE LONG TERM (THURSDAY THROUGH SATURDAY)... THE LARGE SCALE TROUGH CONTINUES TO ROTATE OVER THE REGION...AND THE FINAL TROUGH AXIS ROTATES THROUGH TUESDAY EVENING AND NIGHT BEFORE THE TROUGH FINALLY HIGH TAILS IT OUT OF HERE. WEAK RIDGING ALOFT OCCURS WEDNESDAY THEN AN UPPER LEVEL LOW AND WEAK VORT STREAMER SWING THROUGH THURSDAY. ZONAL FLOW THURSDAY NIGHT TRANSITIONS TO WEAK RIDGING LATE ON FRIDAY. AT THE SURFACE HIGH PRESSURE CONTINUES DOWN THE PLAINS AND PASSES OVER THE CENTRAL MISSISSIPPI VALLEY TUESDAY AFTERNOON BEFORE REACHING THE SE US LATE WEDNESDAY. MEANWHILE...LOW PRESSURE DROPS OVER SASKATCHEWAN TUESDAY AFTERNOON AND HOOKS TO THE NE OVER ONTARIO LATE WEDNESDAY. THE LOWS COLD FRONT PASSES THROUGH THE REGION THURSDAY WITH THE GFS A BIT FASTER WITH THE FROPA THAN THE ECMWF. HIGH PRESSURE BUILDS DOWN THE PLAINS THURSDAY...BUT THIS TIME IT LOOKS AS IF IT WILL PASS OVER THE REGION FRIDAY. WHILE JUST ABOUT A WEEK AWAY...GUIDANCE HINTS AT A FRONT/UPPER LEVEL VORT STREAMER PUSHING NORTH AND POSSIBLY CREATING PRECIP FRIDAY. THE REGION REMAINS DRY...EXCEPT FOR LAKE EFFECT SNOW OVER THE EASTERN HALF OF THE LAKE...THROUGH WEDNESDAY. SNOW IS EXPECTED ALONG THE COLD FRONT MID WEEK. KEPT THE CHANCE OF PRECIP FOR FRIDAY INTO SATURDAY AS THE FRONT/UPPER LEVEL VORT STREAMER TRANSITION THROUGH THE REGION. BUT...GUIDANCE HAS BACKED OFF ON THE FORCING AND MOISTURE WITH THIS FEATURE SO HAVE LOWERED POPS A BIT. THE JET LIFTS TO THE NORTH A SMIDGE SATURDAY SO MAY SEE TEMPS IN THE FAR SOUTHERN AREAS GET CLOSE TO FREEZING SATURDAY. THAT BEING SAID KEPT SNOW FOR EVERYONE. FOR TEMPS...RELIEF FROM THE COLD IS IN STORE FOR THOSE WHO ARE PATIENT. MONDAY NIGHT STILL LOOKS BITTERLY COLD AND THE GOING FORECAST LOOKED VERY REASONABLE SO DID NOT MAKE ANY CHANGES TO THE TEMPS. WINDS CONTINUE TO LOOK LIGHTER THAN PREVIOUSLY THOUGHT...WHICH LEADS TO MIN WIND CHILLS BETWEEN -30 AND -45F. FOR REFERENCE MIN 925MB TEMPS WILL BE -24 TO -26C MONDAY EVENING AND ACTUALLY RISE SLOWLY OVERNIGHT TO AROUND -22C BY MORNING. DESPITE THE RISING TEMPS ALOFT...SKIES SHOULD BE RATHER CLEAR ALLOWING AMPLE COOLING OVERNIGHT. THINKING TEMPS WILL ACTUALLY DROP BY A COUPLE OF DEGREES BY DAYBREAK BEFORE RISING TO AROUND 0F TUESDAY. WE DROP BACK BELOW ZERO TUESDAY NIGHT WITH LOWS OF -5 TO -15F AND MIN WIND CHILLS OF -15 TO -30F. BUT HAVE NO FEAR...THE WARM UP BEGINS WEDNESDAY WITH WAA RESULTING IN MAX TEMPS AROUND 20. COULD ACTUALLY BE A DEGREE OR TWO WARMER THAN FORECAST. WENT ON THE CONSERVATIVE SIDE AS I AM NOT SURE HOW WELL WARMING ALOFT WILL MIX TO THE SURFACE. GUSTS UP TO 25 MPH WILL CREATE WIND CHILLS AROUND ZERO WEDNESDAY AFTERNOON. THURSDAY ALSO LOOKS JUST BELOW NORMAL THURSDAY BEFORE THE NEXT WAVE OF COLD AIR PUSHES IN BEHIND THE COLD FRONT THURSDAY. LOWS DROP OFF TO +5 TO -5F THURSDAY NIGHT BUT TEMPS REBOUND LATE NEXT WEEK WITH NEAR NORMAL TEMPS PSBL BY SATURDAY. JEE && .CLIMATE... DAILY TEMPERATURE RECORDS: CHICAGO ROCKFORD JAN 27... RECORD LOW MIN TEMP -10 -13 RECORD LOW MAX TEMP -1 -2 JAN 28... RECORD LOW MIN TEMP -13 -22 RECORD LOW MAX TEMP -3 -5 JAN 29... RECORD LOW MIN TEMP -16 -20 RECORD LOW MAX TEMP -6 -9 DEUBELBEISS && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 20Z... * WEST WINDS TURNING NORTHWEST WITH GUSTS 20-26KT AT ONSET. * NW WINDS BECOME VERY GUSTY QUICKLY ARND 1Z THRU 9Z...WITH GUSTS BETWEEN 3-9Z NEARING 40KT AND MAY BE HIGHER. * BURST OF SNOW WITH SNOW ARRIVAL...THEN ENDS ARND 3Z WITH CONTINUED BLOWING SNOW. * POSSIBLE IFR VSBYS WITH BURST OF SNOW...AND BLOWING SNOW THIS EVENING THRU OVERNIGHT. * MVFR CIGS DEVELOPING THIS AFTN THEN LIKELY PERSIST THRU DAYBREAK MON. BEACHLER //DISCUSSION...UPDATED 18Z... VERY HAZARDOUS AVIATION CONDITIONS SETTING UP FOR THIS EVENING THROUGH THE OVERNIGHT HOURS. ACRTIC FRONTAL BOUNDARY CONTINUES TO BE THE FOCUS...WITH RESPECT TO TIMING. WINDS HAVE SHIFTED TO THE WEST AND BEGAN TO GUSTS AT TIMES TO ARND 20-25KT. CIGS HAVE BEGUN TO LOWER AS WELL...NEARING MVFR CONDS. WITH THE POWDERY NATURE OF THE SNOWFALL FROM EARLIER THIS MORNING...THE GUSTS WILL EASILY PRODUCE BLOWING SNOW AND LOWER VSBYS BRIEFLY. HOWEVER IT APPEARS CONDS WILL BE MUCH LOWER ONCE THE ARCTIC BOUNDARY ARRIVES ARND 1-2Z...AND WILL BRING VSBYS DOWN FURTHER WITH A BURST OF LIGHT SNOW AND BLOWING SNOW. POSSIBLY SEE VSBYS DOWN TO 1/4 TO 1/2 MILE WITHIN THIS BURST. WINDS WILL RAPIDLY RAMP UP TO GUSTS NEARING 36KT AT THE ONSET. THEN GUSTS WILL RISE EVEN HIGHER NEARING 40KT BY 3Z. CURRENTLY HAVE INDICATED VSBYS MAY IMPROVE A LITTLE AT 3Z...HOWEVER CONFIDENCE IS LOW GIVEN THE POTENTIAL FOR VERY GUSTY WINDS PERSISTING AND LIKELY CAUSING CONTINUED BLOWING SNOW. GUIDANCE INDICATES GUSTS MAY BEGIN TO COME DOWN SLIGHTLY BY 9Z...WITH CIGS HOVERING ARND HIGH END MVFR AND LOW END VFR THRU DAYBREAK. THEN A STRONG PUSH OF DRY AIR SHOULD BRING PARTIAL CLEARING TO THE CLOUDS...HOWEVER THIS MAY ONLY BE TEMPORARY AND A CLOUD DECK APPEARS TO BE POISED TO REDEVELOP LATE MON MORNING. WINDS REMAINING GUSTY AT TIMES FROM THE NORTHWEST BUT NOT AS STRONG AT 20-26KT. BEACHLER //ORD AND MDW CONFIDENCE...UPDATED 20Z... * HIGH CONFIDENCE IN WIND DIR/SPEED/GUSTS. * MEDIUM CONFIDENCE IN CIGS FORECAST. * HIGH CONFIDENCE IN FRONTAL BOUNDARY ARRIVAL...AND SNOW ARRIVAL/ENDING. * MEDIUM/HIGH CONFIDENCE IN BLOWING SNOW IMPACT ON VSBYS. BEACHLER //OUTLOOK FOR ORD/MDW FOR 00Z TUESDAY-12Z SUNDAY...UPDATED 12Z... MONDAY NIGHT...VFR. TUESDAY...VFR. WEDNESDAY...VFR. THURSDAY...CHANCE OF SNOW AND IFR. FRIDAY...CHANCE OF SNOW AND IFR FRIDAY EVENING. SATURDAY...CHANCE OF SNOW AND IFR. RC && .MARINE... 151 PM CST WITH HIGH PRESSURE LINGERING ACROSS THE REGION EARLIER THIS MORNING...RELATIVELY LIGHTER SPEEDS WERE OBSERVED EARLIER TODAY. ALTHOUGH...A QUICKLY APPROACHING AREA OF LOW PRESSURE AND ASSOCIATED BOUNDARY HAS SINCE CHANGED THESE CONDITIONS...AND REPLACED THEM WITH AN INCREASING WIND FIELD OVER THE ENTIRE LAKE. 20 TO 30 KT WINDS CONTINUE TO BE OBSERVED PRIMARILY OVER THE NEARSHORE AND SOUTHERN HALF OF THE LAKE...BUT WITH THIS QUICKLY CHANGING AS SPEEDS ARE CURRENTLY INCREASING OVER THE NORTHERN HALF. LOW PRESSURE WILL SLOWLY MOVE EAST ACROSS THE GREAT LAKES REGION THIS AFTERNOON THROUGH TONIGHT WITH A STRONG COLD FRONT MOVING ACROSS THE LAKE THIS EVENING. AS THIS OCCURS...WINDS WILL TURN TO THE NORTHWEST WHILE RAPIDLY INCREASING WITH GALES QUICKLY BEING OBSERVED OVER THE ENTIRE LAKE AND NEARSHORE BY LATE THIS AFTERNOON AND EARLY EVENING. NORTHWEST GALES CAN EXPECTED TONIGHT THROUGH MONDAY MORNING...WITH GALE FORCE GUSTS LINGERING INTO THE REST OF THE DAY MONDAY. ITS EVEN POSSIBLE THAT PREVAILING GALES COULD LINGER SOMEWHAT LONGER THAN THE CURRENT GALE WARNING THROUGH MID MORNING MONDAY...BUT WITH CONFIDENCE LOW WITH REGARDS TO THE POSSIBILITY...HAVE DECIDED TO LEAVE THE CURRENT HEADLINE END TIME AND JUST MENTION GALE FORCE GUSTS. A PERIOD OF ELEVATED WESTERLY WINDS WILL CONTINUE THROUGH THE MIDDLE PORTION OF THE WEEK BEFORE WINDS TURN MORE SOUTHERLY BUT ALSO INCREASE ONCE AGAIN. RODRIGUEZ && .LOT WATCHES/WARNINGS/ADVISORIES... IL...WINTER WEATHER ADVISORY...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008- ILZ010-ILZ011-ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-ILZ021- ILZ022-ILZ023-ILZ032-ILZ033-ILZ039 UNTIL 6 AM MONDAY. WIND CHILL WARNING...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010- ILZ011-ILZ012-ILZ013-ILZ014-ILZ020-ILZ022-ILZ023...3 AM MONDAY TO 9 AM WEDNESDAY. WIND CHILL WARNING...ILZ019-ILZ021-ILZ032-ILZ033-ILZ039...3 AM MONDAY TO NOON TUESDAY. IN...WIND CHILL WARNING...INZ001-INZ002-INZ010-INZ011...3 AM MONDAY TO 9 AM WEDNESDAY. WINTER WEATHER ADVISORY...INZ001-INZ002-INZ010-INZ011-INZ019 UNTIL 6 AM MONDAY. WIND CHILL WARNING...INZ019...3 AM MONDAY TO NOON TUESDAY. LM...GALE WARNING...LMZ080-LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777- LMZ779-LMZ868-LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 9 AM MONDAY. HEAVY FREEZING SPRAY WARNING...LMZ080-LMZ261-LMZ362-LMZ364- LMZ366-LMZ563-LMZ565-LMZ567-LMZ669-LMZ671-LMZ673-LMZ675- LMZ777-LMZ779-LMZ868-LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...6 PM SUNDAY TO 4 AM WEDNESDAY. GALE WARNING...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565...9 PM SUNDAY TO 9 AM MONDAY. GALE WARNING...LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-LMZ745...6 PM SUNDAY TO 9 AM MONDAY. HEAVY FREEZING SPRAY WARNING...LMZ740-LMZ741-LMZ742-LMZ743- LMZ744-LMZ745...6 PM SUNDAY TO 10 PM MONDAY. SMALL CRAFT ADVISORY...NEARSHORE WATERS UNTIL 6 PM SUNDAY. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1141 AM CST SUN JAN 26 2014 .DISCUSSION... 1105 AM CST THE WINTER WEATHER ADVISORY CONTINUES THIS AFTERNOON FOR BLOWING SNOW...WHICH WE HAVE RECEIVED NUMEROUS REPORTS OF IN OPEN AREAS AND JUST EXPERIENCED A SEVERAL MINUTE PERIOD OF 1/4SM IN BLOWING SNOW HERE AT THE WFO WITH A GUST TO 37 MPH. IN ADDITION...PNT RECENTLY GUSTED TO 45 MPH. FOR THE FORECAST TONIGHT HAVE INCREASED GUST STRENGTH...ESPECIALLY SOUTH...AND HAVE BOOSTED POPS FOR SNOW SHOWERS IMMEDIATELY BEHIND THE FRONT. WHILE THESE FURTHER RAISE ONGOING CONCERNS ABOUT BLIZZARD POTENTIAL FOR THIS EVENING IN THE WESTERN AND SOUTHERN FORECAST AREA...CONTINUE TO HIT HARD IN THE ONGOING HEADLINE. RAPID UPPER TO MID-LEVEL FLOW OVER THE AREA IS SEEN ON WATER VAPOR LATE THIS MORNING WITH THE WAVE ALREADY OVER CENTRAL OH THAT PRODUCED THE EARLIER TWO TO THREE AND A HALF INCHES OF SNOW. LOW- LEVEL WARM AIR ADVECTION IS NOW QUICKLY MOVING INTO THE REGION WITH TEMPERATURES IN THE MID 30S SOUTH OF INTERSTATE 80 AND EVOLVING QUICKLY EASTWARD. THE WINDS IMMEDIATELY FOLLOWING THIS WARM FRONT WAS THE ZONE OF RAPID PRESSURE CHANGE THAT BROUGHT THE AFOREMENTIONED HIGHER GUSTS. SPEEDS WILL REMAIN GUSTY IN THIS CLIPPER WARM SECTOR THIS AFTERNOON. WITH THE MILD TEMPERATURES AND EVEN DEW POINTS IN THE UPPER 20S...SOME SNOW MELT WILL OCCUR IN THESE PARTS OF THE FORECAST AREA...AND POSSIBLY MAKE EXISTING SNOW COVER SOMEWHAT LESS SUSCEPTIBLE TO BLOWING TONIGHT. WILL CONTINUE TO MAKE CALLS AND INQUIRIES FOR VISIBILITY OBSERVATIONS. THE WORSE CONDITIONS REMAIN THIS AFTERNOON...THE MORE WE WOULD LEAN TO AN UPGRADE TO A BLIZZARD WARNING FOR TONIGHT WHEN CONDITIONS ARE LIKELY TO BE WORSE FOR A SEVERAL HOUR PERIOD. AS FOR THE WEATHER TONIGHT...THE PRONOUNCED UPPER LOW IS PROGRESSING SOUTH INTO THE CONUS ON THE WESTERN SIDE OF THE MASSIVE LONG WAVE TROUGH. A STAGGERING 250M HEIGHT FALLS WERE OBSERVED AT 500MB THIS MORNING IN SOUTHERN CANADA WITH THIS...WHICH IS EXTREMELY IMPRESSIVE FOR A NORTHERN STREAM WAVE DROPPING NEARLY DUE SOUTH. THESE HEIGHT FALLS WILL EVOLVE DIRECTLY OVER THE FORECAST AND CORRELATE TO NARROW BUT STRONG FORCING IMMEDIATELY ON THE LEADING EDGE OF THE WAVES POTENTIAL VORTICITY. MODELS ARE IN GOOD AGREEMENT WITH THIS OCCURRING...DESPITE DIFFERENCES IN PLACEMENT AND HOURLY TIMING. THIS CERTAINLY APPEARS A GOOD SETUP FOR SNOW SHOWERS...OR EVEN A RIBBON OF SNOW WITH THIS. CROSS SECTIONS INDICATE STRONG SLOPED FRONTOGENESIS OF THE ELEVATED FRONTAL BOUNDARY...WITH MODEST INSTABILITY /NEGATIVE EPV/ DIRECTLY ABOVE THAT. SO HAVE BOOSTED POPS WITH LIKELY MENTIONED MAINLY SOUTH OF I-88. HIGH RES MODELS SUPPORT HIGH REFLECTIVITY WITHIN THIS FORCING AND IT IS ATOP THE INTENSE PRESSURE GRADIENT IMMEDIATELY BEHIND THE COLD FRONT...SO THE COMBO OF BRIEFLY MODEST SNOW AND HIGH WINDS LOOKS TO OCCUR FOR 1-2 HRS IN SOME PLACES...AGAIN ESPECIALLY THE CENTRAL AND SOUTHERN FORECAST AREA. THATS WHERE WHITEOUT CONDITIONS WILL VERY LIKELY OCCUR...AT LEAST BRIEFLY. WIND GUSTS HAVE BEEN BOOSTED TO 45 MPH FOR A 1-2 HR PERIOD DURING THIS TIME AND ALREADY SEEING THESE TYPE OF OBSERVATIONS UPSTREAM IN IA. CONTINUE TO STRESS THAT CONDITIONS WILL RAPIDLY DETERIORATE THIS EVENING ACROSS THE ENTIRE FORECAST AREA...WITH DRIVING CONDITIONS BECOMING VERY POOR IN OUTLYING LOCATIONS AND LIKELY REMAINING SO THROUGH DAYBREAK MONDAY IF NOT WELL INTO MONDAY. MTF && .PREV DISCUSSION... 325 AM CST SEVERAL WEATHER HAZARDS EXPECTED OVER THE NEXT FEW DAYS...INCLUDING ONGOING SNOW THIS MORNING...VERY WINDY CONDITIONS LEADING TO BLOWING SNOW AND POSSIBLE BLIZZARD LIKE CONDITIONS THIS EVENING AND TONIGHT...AND THE ARRIVAL OF ANOTHER ARCTIC AIRMASS TONIGHT WHICH WILL STAY IN THE AREA THROUGH MIDWEEK. THIS MORNING AND AFTERNOON... LOW PRESSURE LIES OVER NORTHERN IOWA EARLY THIS MORNING WITH A WARM FRONT LIFTING ACROSS THE MISSISSIPPI VALLEY. AHEAD OF THE FRONT...MODERATE TO AT TIMES HEAVY SNOW IS PUSHING EAST ACROSS NORTHERN ILLINOIS IN AN AREA OF STRONG ISENTROPIC ASCENT. STRONG ASCENT AND A DEEP ISOTHERMAL LAYER ON THE EDGE OF THE SNOW GROWTH ZONE WILL PROMOTE DRIER THAN AVERAGE SNOW TO LIQUID RATIOS AND EXPECT A WINDOW OF NEARLY INCH PER HOUR SNOW RATES. GOING FORECAST WAS MOSTLY ON TRACK THOUGH MADE SOME TWEAKS TO THE BAND OF 3-5 INCHES WHICH NOW APPEARS TO BE ON EITHER SIDE OF A LINE FROM THE ROCKFORD AREA INTO THE SOUTH SUBURBS OF CHICAGO. ELSEWHERE...2-4 INCHES STILL APPEARS FAVORABLE...EXCEPT SOUTH OF A PERU TO FOWLER LINE WHERE AMOUNTS WILL QUICKLY TAPER OFF. A FEW DISTURBANCES ARE NOTED ON WATER VAPOR IMAGERY THIS MORNING. THE FIRST OVER THE UPPER MIDWEST THIS MORNING AND IS PROGGED TO PUSH EAST OF THE CWA BY MID TO LATE THIS MORNING. THIS SHOULD MARK THE BACK EDGE OF THE SNOW LATER THIS MORNING ALONG WITH THE WARM FRONT LIFTING ACROSS THE AREA. TEMPERATURE MAY PUSH THE FREEZING MARK THIS AFTERNOON SOUTH OF I-80...AND AT THE SAME TIME WINDS WILL BECOME VERY BREEZY. UPSTREAM OBS OVER SOUTHERN IOWA AND NORTHERN MISSOURI SHOW SOUTHWEST WINDS GUSTING TO AROUND 35 MPH AND EXPECT THESE STRONGER WINDS TO TRANSLATE ACROSS THE SOUTHERN PORTIONS OF THE CWA BY LATE THIS MORNING. ANOTHER WAVE NOTED ON WATER VAPOR IMAGERY IS DIGGING SOUTH ACROSS THE CANADIAN PRAIRIES THIS MORNING. THIS WAVE WILL ARRIVE LATER THIS EVENING ALONG WITH A STRONG ARCTIC COLD FRONT. THIS EVENING AND TONIGHT... THE ARCTIC FRONT WILL PUSH ACROSS THE REGION EARLY THIS EVENING. SHEARED MID LEVEL VORT WILL PIVOT ACROSS THE REGION THIS EVENING PROVIDING BROAD SCALE ASCENT WHILE F-GEN BAND IS SET TO PUSH SOUTHEAST ACROSS THE AREA WITH MORE FOCUSED LOW LEVEL FORCING. SOUNDINGS SHOW DRY ADIABATIC LAPSE RATE UP TO AROUND H8 WITH A SHALLOW SATURATED LAYER UP TO AROUND H7. THE BETTER FORCING AND MOISTURE IS WELL CO-LOCATED IN THE SNOW GROWTH ZONE ACROSS THE SOUTHERN COUNTIES BUT FALLS WITHIN COLDER AIR FARTHER NORTH WHICH WILL LEAD TO INEFFICIENT SNOW PRODUCTION. IN ADDITION...STRONG SHEAR WITH WINDS QUICKLY PUSHING TOWARDS 80KTS AT H7 WOULD BE DETRIMENTAL TO SNOW GROWTH. SHALLOW MOISTURE AND FORCING QUICKLY TRANSLATING ACROSS THE AREA LEAD TO LOW CONFIDENCE IN SEEING MUCH IN THE WAY OF ADDITIONAL ACCUMULATIONS...BUT THE BEST CHANCES WILL BE WITHIN THE F-GEN BAND WHICH LATEST GUIDANCE SHOWS SETTING UP SOUTH OF I-80. MORE CONCERNING TONIGHT WILL BE THE SHARP UPTICK IN WINDS BEHIND THE FRONT. THE AXIS OF STRONGEST PRESSURE RISES WILL PUSH JUST SOUTH OF THE CWA...BUT THE CWA WILL STILL SEE IMPRESSIVE PRESSURE RISES OF 10-12MB/6HR...ESPECIALLY IN THE WEST/SOUTHWEST PORTIONS OF THE CWA. MODELS STILL ADVERTISE 40-45KT WINDS AT THE TOP OF THE MIXED LAYER WHICH SHOULD MIX EFFICIENTLY TO THE SURFACE GIVEN THE STEEP LAPSE RATES. LOCAL 8KM WRF SHOWS A FEW HOUR WINDOW OF WIND GUSTS PUSHING 40 MPH BEFORE EASING SLIGHTLY INTO THE 30 TO 35 MPH RANGE. GIVEN THE DRY SNOW FALLING THIS MORNING AND THE POTENTIAL FOR ANY ADDITIONAL SNOW THIS EVENING...REMAIN CONCERNED ABOUT THE IMPACTS FROM BLOWING SNOW. TEMPERATURES MAY PUSH ABOVE THE FREEZING MARK ACROSS THE FAR SOUTHERN COUNTIES THIS AFTERNOON WHICH MAY ADD SOME DENSITY TO THE SNOW...BUT EVEN IF THIS IS THE CASE SUSPECT IT MAY BE SOMEWHAT NEGLIGIBLE GIVEN HOW COLD THE GROUND TEMPS ARE. ANY ADDITIONAL SNOWFALL WITH THE EXPECTED WINDS THOUGH WILL ONLY COMPOUND VISIBILITY ISSUES WITH BLOWING SNOW. THE MAIN LIMITING FACTOR AND REASON FOR NOT GOING WITH A BLIZZARD HEADLINE AT THIS TIME WILL BE THE SHORT DURATION OF THE STRONGEST WINDS. WHILE I FULLY EXPECT WINDS IN EXCESS OF 35 MPH AND WHITEOUT CONDITIONS...AM NOT CONFIDENT ABOUT 3 HOURS OF OF 35 MPH WINDS TO MEET THE STRICT CRITERIA FOR A BLIZZARD WARNING. BUT TO BE CLEAR...EVEN WITH WINDS BLOWING 30 TO 35 MPH OVER THE DRY SNOW...THERE WILL BE PERIODS OF NEAR ZERO OR ZERO VISIBILITY PARTICULARLY IN OPEN AND RURAL AREAS. WHITEOUT CONDITIONS WILL BE POSSIBLE INTO THE PREDAWN HOURS MONDAY. IT PROBABLY WILL NOT BE AS BAD AS YOU HEAD INTO THE HEART OF THE CHICAGO METRO AREA. NEXT WEEK... WELL ADVERTISED COLD SNAP STILL ON TRACK FOR THE FIRST HALF OF NEXT WEEK. A STRONG HIGH WILL BUILD INTO THE PLAINS WITH RIDGING EXTENDING TOWARDS THE OHIO VALLEY. DESPITE THE DEEP TROUGH OVERHEAD...DO NOT SEE ANY CHANCES FOR PRECIP. MAIN STORY CONTINUES TO BE THE COLD WITH RECORD LOWS POSSIBLE TUESDAY. STILL LOOKING AT WIDESPREAD WIND CHILLS AROUND 40 BELOW NORTH OF I-80 TUESDAY WITH -30 TO -40 SOUTH OF I-80. A WIND CHILL WARNING REMAINS IN EFFECT FROM EARLY MONDAY MORNING THROUGH MID MORNING WEDNESDAY FOR THE ENTIRE CWA...EXCEPT UNTIL TUESDAY AFTERNOON FOR THE SOUTH/SOUTHWEST TIER OF COUNTIES. FOR THE LATTER HALF OF THE WEEK...THE UPPER AIR PATTERN IS STILL PROGGED TO DAMPEN SOME...WHICH WILL ALLOW TEMPS TO MODERATE...BUT WILL REMAIN WELL BELOW NORMAL. DEUBELBEISS && .CLIMATE... DAILY TEMPERATURE RECORDS: CHICAGO ROCKFORD JAN 27... RECORD LOW MIN TEMP -10 -13 RECORD LOW MAX TEMP -1 -2 JAN 28... RECORD LOW MIN TEMP -13 -22 RECORD LOW MAX TEMP -3 -5 JAN 29... RECORD LOW MIN TEMP -16 -20 RECORD LOW MAX TEMP -6 -9 DEUBELBEISS && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 16Z... * SOUTH-SOUTHWEST WINDS BECOMING WEST BY MID-DAY AND THEN GUSTING TO ARND 25 KT THROUGH THE AFTN. * BLOWING SNOW FROM AFTN ON. * WEST WINDS GUSTING TO 30-35KT THIS EVENING DIMINISHING TO GUSTS ARND 25 KT AFTER MIDNIGHT. * SNOW SHOWERS PSBL THIS EVENING WITH MVFR CIGS AND VSBY. JEE //DISCUSSION...UPDATED 12Z... A CLIPPER SYSTEM OVER IOWA WILL LIFT ACROSS SOUTHERN LAKE MICHIGAN AND THEN TO NORTHERN LOWER MICHIGAN TODAY. THIS WILL RESULT IN WINDS SHIFTING QUICKLY FROM SOUTHERLY TO SOUTHWESTERLY AND THEN TO WESTERLY WITH GUSTS IN THE MID 20S BY AROUND MID DAY. THIS COULD CAUSE VSBY ISSUES WITH BLOWING SNOW IN OPEN AREAS...MOST LIKELY AT RFD/DPA. AN ARCTIC FRONT AND UPPER LEVEL TROUGH WILL SURGE SOUTH ACROSS THE AREA LATE THIS AFTERNOON INTO EARLY THIS EVENING. WEST- NORTHWEST WINDS WILL INCREASE FURTHER TO 20 TO 25 KT SUSTAINED AND GUSTS TO 30 TO 35 KT...HIGHEST OUT TOWARD RFD. OCCASIONAL HIGHER GUSTS OVER 40 KT ARE POSSIBLE DUE TO THE BITTERLY COLD AIR POURING INTO THE REGION AND STRONG PRESSURE RISES. FURTHERMORE...THE POTENTIAL ALSO EXISTS FOR SNOW SHOWERS TO DEVELOP IN ASSOCIATION WITH THE ARCTIC FRONT. THE MAIN UNCERTAINTY IS WITH HOW WIDESPREAD AND INTENSE THE SNOW SHOWERS WILL BE THIS EVENING...AS WELL AS IMPACTS ON CIGS. EITHER WAY...THE STRONG WEST-NORTHWEST WINDS ARE LIKELY TO RESULT IN SIGNIFICANT BLOWING AND DRIFTING SNOW AND AT LEAST NEAR BLIZZARD CONDITIONS...WHICH WOULD BE COMPOUNDED BY FALLING SNOW. HAVE INDICATED A TEMPO 1/2 SM VSBY AT RFD AND DPA THIS EVENING...WITH LESSER CONFIDENCE IN THIS OCCURRING AT ORD/MDW/GYY. AS AN ADDITIONAL NOTE ON THE SNOW THIS EVENING...RECENT RUNS OF ONE OF THE HIGHER RESOLUTION NEAR TERM MODELS BRINGS A MORE INTENSE BAND OF SNOW ACROSS THE AREA FROM ROUGHLY 23-05Z...WHILE MOST OF THE REST OF THE GUIDANCE KEEPS THIS FEATURE SOUTH OF THE TERMINALS AND LIGHTER SNOW SHOWERS AFFECTING THE TERMINALS. BELIEVE THAT THE SCENARIO PORTRAYED BY THE ONE HIGHER RES MODEL IS OF LOWER PROBABILITY AT THIS TIME...BUT THIS IS CERTAINLY SOMETHING TO FURTHER ASSESS TODAY...AS CIG/VSBY IMPACTS WOULD BE MUCH MORE SIGNIFICANT FOR ALL TERMINALS IF THIS WERE TO OCCUR. WINDS WILL ONLY SLOWLY DIMINISH OVERNIGHT TONIGHT...KEEPING THE THREAT FOR BLOWING AND DRIFTING SNOW AND VSBY REDUCTIONS GOING. HAVE KEPT MVFR VSBY RESTRICTIONS AT RFD/DPA...WHICH CONCEIVABLY COULD BE AT LEAST PERIODIC IFR. RC //ORD AND MDW CONFIDENCE...UPDATED 16Z... * LOW CONFIDENCE IN EXTENT OF BLOWING SNOW IMPACTS ON VSBY. * MEDIUM-LOW CONFIDENCE IN TIMING AND ASSOCIATED IMPACTS OF SNOW SHOWERS AND BLOWING SNOW EARLY THIS EVENING. * HIGH CONFIDENCE IN WIND TRENDS. JEE //OUTLOOK FOR ORD/MDW FOR 00Z TUESDAY-12Z SUNDAY...UPDATED 12Z... MONDAY NIGHT...VFR. TUESDAY...VFR. WEDNESDAY...VFR. THURSDAY...CHANCE OF SNOW AND IFR. FRIDAY...CHANCE OF SNOW AND IFR FRIDAY EVENING. SATURDAY...CHANCE OF SNOW AND IFR. RC && .MARINE... 432 AM CST AS HAS BEEN ADVERTISED...MANY MARINE CONCERNS...ESPECIALLY THROUGH MONDAY MORNING. A STRONG CLIPPER SYSTEM WILL TRACK SOUTHEASTWARD TO SOUTHERN LAKE MICHIGAN THIS MORNING THEN LIFT BACK NORTHEAST TO LAKE HURON BY THIS EVENING. THIS PATH WILL ENABLE WINDS TO RAMP UP OUT OF THE SOUTHWEST THEN QUICKLY SHIFTING WEST OVER THE SOUTHERN PORTION OF THE LAKE THIS AFTERNOON...WITH GALES DEVELOPING OVER THE SOUTHERN HALF OPEN WATERS. AN ARCTIC COLD FRONT WILL SURGE SOUTHWARD ACROSS THE SOUTH HALF THIS EVENING...WITH VERY STRONG PRESSURE RISES AND EXTREMELY UNSTABLE CONDITIONS ENABLING GALES TO RAMP UP TO 45 KT. ONCE THE LOW PRESSURE TROUGH MOVES FAR ENOUGH EAST BY MID EVENING...NORTHWEST GALES WILL ALSO DEVELOP ON THE NORTH HALF OF THE LAKE. WILL NEED TO WATCH FOR AN EARLIER ONSET THAN EXPECTED THERE. BITTERLY COLD AIR RUSHING OVER THE LAKE THIS EVENING WILL ALSO SET THE STAGE FOR HEAVY FREEZING SPRAY...SO WENT AHEAD AND ISSUED A WARNING STARTING EARLY THIS EVENING UNTIL EARLY WEDNESDAY FOR THE OPEN WATERS. THERE IS UNCERTAINTY ON HOW STRONG WIND SPEEDS WILL BE ALOFT ON MONDAY...WITH SUSTAINED SPEEDS REMAINING ELEVATED IN THE 25 TO 30 KT RANGE. IF THERE IS STRONGER WINDS ALOFT...THE GALE WARNING MAY NEED TO BE EXTENDED BEYOND MONDAY MORNING FOR AT LEAST A PORTION OF THE LAKE. AS EXPANSIVE HIGH PRESSURE BUILDS ACROSS THE OHIO VALLEY MONDAY NIGHT INTO TUESDAY MORNING...STRONG LOW PRESSURE WILL STALL NEAR HUDSON BAY...KEEPING THE PRESSURE GRADIENT TIGHT FROM CENTRAL LAKE MICHIGAN AND NORTH. SHOULD THERE BE A PERIOD OF SUB GALES ON MONDAY...THEY COULD THEN REDEVELOP FOR AT LEAST THE NORTHERN HALF OF THE LAKE MONDAY NIGHT INTO TUESDAY. WINDS WILL REMAIN ELEVATED WITH VERY COLD AIR STILL OVER THE LAKE...BUT THE NEXT GOOD OPPORTUNITY FOR GALES WILL BE SOUTHWEST GALES ON WEDNESDAY NIGHT AS STRONG LOW PRESSURE PASSES NORTH OF THE LAKE. FOR THE NEARSHORE WATERS...ICE COVERAGE IS A BIG FACTOR...BUT WINDS ARE EXPECTED TO INCREASE TO SMALL CRAFT CRITERIA BY AROUND MIDDAY. THEN A GALE WARNING HAS BEEN ISSUED FROM 6PM THIS EVENING UNTIL 9AM MONDAY. HEAVY FREEZING SPRAY IS LIKELY FOR NON ICE COVERED AREAS THIS EVENING THROUGH MONDAY EVENING. RC && .LOT WATCHES/WARNINGS/ADVISORIES... IL...WINTER WEATHER ADVISORY...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008- ILZ010-ILZ011-ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-ILZ021- ILZ022-ILZ023-ILZ032-ILZ033-ILZ039 UNTIL 6 AM MONDAY. WIND CHILL WARNING...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010- ILZ011-ILZ012-ILZ013-ILZ014-ILZ020-ILZ022-ILZ023...3 AM MONDAY TO 9 AM WEDNESDAY. WIND CHILL WARNING...ILZ019-ILZ021-ILZ032-ILZ033-ILZ039...3 AM MONDAY TO NOON TUESDAY. IN...WIND CHILL WARNING...INZ001-INZ002-INZ010-INZ011...3 AM MONDAY TO 9 AM WEDNESDAY. WINTER WEATHER ADVISORY...INZ001-INZ002-INZ010-INZ011-INZ019 UNTIL 6 AM MONDAY. WIND CHILL WARNING...INZ019...3 AM MONDAY TO NOON TUESDAY. LM...GALE WARNING...LMZ080-LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777- LMZ779-LMZ868-LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...3 PM SUNDAY TO 9 AM MONDAY. HEAVY FREEZING SPRAY WARNING...LMZ080-LMZ261-LMZ362-LMZ364- LMZ366-LMZ563-LMZ565-LMZ567-LMZ669-LMZ671-LMZ673-LMZ675- LMZ777-LMZ779-LMZ868-LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...6 PM SUNDAY TO 4 AM WEDNESDAY. GALE WARNING...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565...9 PM SUNDAY TO 9 AM MONDAY. GALE WARNING...LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-LMZ745...6 PM SUNDAY TO 9 AM MONDAY. HEAVY FREEZING SPRAY WARNING...LMZ740-LMZ741-LMZ742-LMZ743- LMZ744-LMZ745...6 PM SUNDAY TO 10 PM MONDAY. SMALL CRAFT ADVISORY...NEARSHORE WATERS UNTIL 6 PM SUNDAY. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion National Weather Service Lincoln IL 1106 AM CST Sun Jan 26 2014 .DISCUSSION... ISSUED 945 AM CST Sun Jan 26 2014 Huge gradient in weather conditions this morning along forecast area boundaries. KDVN enduring near blizzard conditions while KGBG and C75 have temperatures in the middle to upper 30s melting remaining snow cover. Similar contrast is occuring between KBMI and KPNT. warm front is moving across eastern forecast area this morning and have increased high temperatures througout the forecast area. With temps already near or above freezing through entire forecast area much of any remaining snow cover should be reduced significantly. Areas such as KIJX in which there already is no snow cover will likely approach 50 degrees this afternoon. Enjoy it today as winter returns this evening. Barker && .AVIATION... ISSUED 1105 AM CST Sun Jan 26 2014 Warm front has swept eastward through terminals this morning with winds becoming more westerly. With warming temperatures, snow has been melting and blowing snow should not be an issue today. Any Cigs should remain VFR or possibly occasionally MVFR. There will liley be occasional periods without Cigs particularly at KSPI this afternoon. A strong cold front will push through the terminals this evening (02z-04z) with winds shifting to 300-360 degrees and increasing. With the frontal passage, a short-lived burst of heavy snow is possible given the strong frotogenetic forcing and will include a tempo group to reflect that. Latest HRRR suggests any LIFR vsbys should be less than an hour. A brief period of IFR Cigs will also be possible immediately behind the front. Clearing should develop after 06z with gradual decrease in winds after 12z. Barker && .PREV DISCUSSION... ISSUED 307 AM CST Sun Jan 26 2014 Concern today is the morning light snow, and then the arctic front this evening. SHORT TERM...Today through Tuesday night. Surface data this evening shows the next clipper low pressure center over northwest IA. Upper wave in moisture channel over southeast MN diving to the southeast and moving the enhanced pcpn ahead of it over northern IL. Soundings at ILX and DVN at 00Z showed the air column very dry and so the saturation of airmass has been slowed over region. With dry air, have decreased expected snow amounts this morning over the northern cwa counties. Expect low to move much as progged, moving over northern IL and second upper wave noted in moisture channel will drive the arctic airmass into the region Sunday evening. Models all indicate significant low level jet from the northwest over eastern IA into central IL and northern MO behind the front. Will therefore issue wind advisory for transport of the strong winds to the surface behind the front this evening and overnight. Will be a brief period of light snow for a couple hours after the front, with the significant lift behind the front. Amounts will be very light, so for that reason will see blowing snow reducing visibilities, but amount of snow expected to be light, impact will be short lived. Will have to watch this. Continuing the wind chill warning and advisories as temperatures still falling in arctic air and with strong winds. Monday morning and Tuesday morning will still have the hazardous wind chills. LONG TERM...Wednesday through Sunday. pattern finally shifts during the exceeded period, becoming more zonal in nature aloft. With that, another front moves through on Thursday with light snow, plus an overrunning low on Friday night to also bring some light snow. Goetsch && .ILX WATCHES/WARNINGS/ADVISORIES... WIND ADVISORY from 8 PM this evening to 6 AM CST Monday FOR ILZ027>031-036>038-040>057-061>063-066>068-071>073. WIND CHILL ADVISORY from Midnight tonight to Noon CST Tuesday FOR ILZ040-047>054-056-061>063-066>068-071>073. WIND CHILL WARNING from Midnight tonight to Noon CST Tuesday FOR ILZ027>031-036>038-041>046-055-057. && $$
AREA FORECAST DISCUSSION
NWS TOPEKA KS
353 PM CST Sun Jan 26 2014 .SHORT TERM...(This Evening through Monday) Issued at 351 PM CST SUN JAN 26 2014 Current surface analysis at 20Z shows a prefrontal trough located across southern NE, while the cold front was not far behind in central NE. The pressure gradient behind the front is rather impressive as well as a 20 degree drop in temperature. Given the current southward speed of the front as well as agreement between the latest RAP and HRRR it should enter the forecast area around 23Z. By 01Z the front should stretch along a line from Abilene to Leavenworth, and finally exiting the forecast area around 03Z. Directly behind this front will be a rapid increase in winds gusting 40 to 50 mph across the entire area. There is the possibility across the eastern half of the forecast area that gusts reach 50 to 55 mph directly behind the front. Latest forecast soundings are also suggesting an isolated rain or snow shower along the front. The light precip combined with the strong winds could cause brief periods of low visibilities...no accumulation is expected. Winds will gradually decrease through the overnight hours still sustained around 15 to 20 mph at sunrise. Overnight lows reach the single digits causing wind chills to drop to 15 below zero. Given the latest forecast trends have will make no changes to the wind and wind chill advisories. Tomorrow high pressure continues to build into the region and highs only reach the mid to upper 20s. .LONG TERM...(Monday Night through Sunday) Issued at 351 PM CST SUN JAN 26 2014 For much of Monday night into Tuesday morning, some of the coldest air of the season will be holding strong over the area while surface high pressure dominates the region...centered on the northeast corner of Kansas. Expect mostly clear skies through the overnight hours as well, which along with nearly calm winds indicates a very cold night is in store. It is climatologically very difficult to fall below zero without snow cover, but it certainly seems possible on Tuesday morning, especially in northeast KS. Will then have the base of an upper trough rotate through the area during the day on Tuesday with some indication of enough moisture and ascent to support light snow...mainly over central KS. Will have to see how it plays out as it doesn`t look like much of a precip maker at this point. Even without precip, could see cloud cover building in after the very cold morning which may keep daytime temps lower despite warm advection. Beyond Tuesday, the upper level flow pattern attempts a gradual change away from the sharp northerly flow currently in place. A series of weak disturbances will move through the more zonal flow pattern, but they are so weak, fast moving, and somewhat lacking of deep moisture that any precip chances appear very small locally with each disturbance passing. One such small chance appears to be maximized on Friday, while another is in store for Sunday. The late weekend/early next week storm system has better access to deep moisture with southwesterly upper flow and some Gulf of Mexico influence but the main question is if the storm track will come overhead or hold south of the area. Temperatures through the long term appear fairly stable, and near normal or a bit colder than normal. Also of note, the short wave troughs in the long term do not look nearly as windy as the clipper systems of the past two weeks. && .AVIATION...(For the 18Z TAFs through 18Z Monday Afternoon) Issued at 1132 AM CST SUN JAN 26 2014 Winds will quickly increase as a front pushes southward through the taf sites. Have the front coming in slightly earlier and have increased the winds after frontal passage. Latest guidance is supporting wind gusts approaching 50 mph for a brief period behind the front. There is also a slight chance for flurries or sprinkles along and just behind the front, which could temporarily reduce visibilities and bring in MVFR ceilings. Will continue to monitor the latest data for a possible TEMPO period. && .TOP WATCHES/WARNINGS/ADVISORIES... WIND ADVISORY from 7 PM this evening to 4 AM CST Monday FOR KSZ021>024-026-034>040-054>056-058-059. WIND ADVISORY until 2 AM CST Monday FOR KSZ008>012-020. WIND CHILL ADVISORY from 4 AM to 11 AM CST Monday FOR KSZ010>012. && $$ SHORT TERM...Sanders LONG TERM...Barjenbruch AVIATION...Sanders
AREA FORECAST DISCUSSION
NWS GRAY ME
516 PM EST SUN JAN 26 2014 .SYNOPSIS... LOW PRESSURE WILL MOVE OUT OF THE GREAT LAKES AND INTO NORTHERN NEW ENGLAND BY TOMORROW MORNING. A COLD FRONT WILL MOVE THROUGH DURING THE AFTERNOON HOURS. HIGH PRESSURE BUILDS IN FROM THE SW TUESDAY THROUGH THURSDAY. A COLD FRONT APPROACHES FROM THE WEST ON FRIDAY FOLLOWED BY HIGH PRESSURE FOR THE WEEKEND. && .NEAR TERM /UNTIL 6 AM MONDAY MORNING/... UPDATE...WESTERLY GRADIENT HAS DIMINISHED ON SCHEDULE. WITH VERY LOW DEW POINTS IN PLACE OVER CENTRAL AND NORTHERN AREAS...THIS WILL ALLOW FOR A QUICK DROP IN THE TEMPERATURES OVER THE NEXT COUPLE HOURS. THEY WILL THEN STEADY OFF WITH THE ADVANCE OF HIGH AND MID LEVEL CLOUD COVER...AND FINALLY BEGIN TO RISE OVERNIGHT. PRECIP STILL WELL WEST OF OUR FORECAST AREA. LATEST HRRR RUN BRING STEADY LIGHT SNOW TO EASTERN NEW YORK BY MIDNIGHT...WHICH SHOULD OVERSPREAD OUR MOUNTAINS AND FOOTHILLS THEREAFTER LATE TONIGHT. PREV DISC...SFC RIDGE AXIS IS APPROACHING THE AREA QUICKLY FROM THE W ATTM. WILL SEE GUSTY WLY WINDS DROP WITHIN THE NEXT COUPLE OF HOURS AS A RESULT. HIGH CLOUD SPILLING OVER THE UPR RIDGE AXIS WILL ALSO BEGIN TO ENCROACH ON THE CWFA BETWEEN NOW AND 00Z. IT SHOULD TAKE SEVERAL HOURS FOR THE COLUMN TO SATURATE ENOUGH FOR CIGS TO LOWER AND ANY PCPN TO BEGIN. BROAD WAA AHEAD OF GREAT LAKES LOW PRES WILL SUPPORT SCT SHSN...ESPECIALLY ACROSS THE NRN ZONES WHERE TOPOGRAPHY WILL ASSIST IN LIFT. IN ADDITION...INITIALLY A VERY COLD AIR MASS WILL SUPPORT SOME OCEAN EFFECT SHSN REACHING INTO PARTS OF THE MIDCOAST AS WINDS BECOME MORE SWLY. COULD SEE A COUPLE INCHES OF ACCUM IN THE HIGHER TERRAIN BY MORNING...WITH A DUSTING TO AN INCH FARTHER S. LOW TEMPS FOR THE OVERNIGHT ARE VERY SIMILAR TO TODAY/S HIGHS. AFTER AN INITIAL DROP NEAR SUNSET...WAA SFC AND ALOFT WILL KEEP READINGS MOSTLY STEADY OR RAISE TEMPS THRU THE NIGHT TO WITHIN A DEGREE OR TWO OF CURRENT READINGS. && .SHORT TERM /6 AM MONDAY MORNING THROUGH MONDAY NIGHT/... SCT SHSN LINGER IN WAA MON MORNING...WHILE COLD FNT APPROACHES FROM THE W. FNT SHOULD ENTER WRN CWFA NEAR NOON ACROSS WRN ZONES...AND EXIT THE ERN ZONES BY 00Z. ALONG FNT GUIDANCE INDICATES ENOUGH FORCING FOR A CONCENTRATED BAND OF SHSN. SFC WAA AHEAD OF FROPA WILL BRING TEMPS ABOVE FREEZING FOR THE COAST...WHERE SHSN MAY MIX WITH RA AT TIMES. LLVL RH PROFILES AND STEEPENING LAPSE RATES COULD SUPPORT A COUPLE OF MORE INTENSE SQUALLS WITHIN THE LINE OF SHSN. QUICKLY FALLING TEMPS AFTER THE FROPA WILL ALSO LEAD TO SOME ICY SPOTS WHERE SNFL HAS MELTED. LINGERING UPSLOPE SHSN COULD TACK ON ANOTHER COUPLE OF INCHES IN THE MTNS...BEFORE SLOWLY TAPERING OFF. && .LONG TERM /TUESDAY THROUGH SUNDAY/... A PAIR OF SURFACE CYCLONES REMAIN STUCK IN CYCLONIC FLOW ALOFT TO OUR NORTH ON TUESDAY. THE MAIN UPPER LOW LIFTS NORTHWARD AS RIDGING BREAKS DOWN OVER THE WESTERN CONUS...ALLOWING THE FLOW TO BECOME LESS AMPLIFIED FOR THE MIDWEEK PERIOD. AT THE SURFACE...HIGH PRESSURE OVER THE CENTRAL CONUS CONTINUES TO DOMINATE AS IT MOVES INTO THE SE STATES. THE HIGH SHIFTS OFFSHORE IN THE THURSDAY/FRIDAY TIME FRAME. IN THE INTERIM THIS FEATURE WILL BE THE DOMINANT WEATHER MAKER FOR NEW ENGLAND AS IT BUILDS IN FROM THE SW. THIS WILL KEEP RELATIVELY COLD AIR IN PLACE...HOWEVER AS THE AIRMASS MODERATES TEMPERATURES WILL IMPROVE AS THE WEEK GOES ON. TUESDAY AND WEDNESDAY LOOK ESPECIALLY COLD WITH DOWNSLOPING FLOW CLEARING CLOUDS OUT OVER THE COASTAL PLAIN. THIS ALONG WITH LIGHT WINDS WILL CONTRIBUTE TO EFFICIENT RADIATIONAL COOLING. FORECAST SOUNDINGS ARE INDICATING A VERY DRY AIRMASS AS WELL WITH ANY MOISTURE TRANSPORT EFFECTIVELY BLOCKED. MAY NEED WIND CHILL ADVISORIES FOR MUCH OF THE TUESDAY/WEDNESDAY TIME FRAME GENERALLY NORTH OF A LINE FROM MOUNT WASHINGTON TO LAKE MOXIE. THE NEXT CHANCE OF PRECIPITATION OCCURS AS A FRONT NEARS FROM THE WEST IN THE THURSDAY NIGHT/FRIDAY MORNING TIME FRAME. MODELS SEEM TO BE AT LEAST PARTIALLY WASHING THIS OUT AS THE UPPER LEVEL FORCING AND PARENT SURFACE LOW FILL. QPF/SNOWFALL WILL BE LIGHT WITH THE AIRMASS REMAINING ON THE DRY SIDE THROUGHOUT THE LAYER. OTHER DISTURBANCES IN SW FLOW ALOFT MAY AFFECT NEW ENGLAND OVER THE WEEKEND...HOWEVER TEMPORAL AND SPATIAL DETAILS ARE NOT BEING RESOLVED WELL BY THE LONG TERM MODELS. && .AVIATION /22Z SUNDAY THROUGH FRIDAY/... SHORT TERM...VFR CONDITIONS TO PREVAIL FOR THE FIRST HALF OF THE NIGHT. BROAD WAA WILL RESULT IN SCT SHSN FOR MUCH OF THE AREA...WITH MVFR OR LOWER CONDITIONS POSSIBLE WITH ANY SNFL. SHOULD SEE A BRIEF BREAK OUTSIDE OF THE MTNS ON MON...UNTIL COLD FNT SWEEPS THRU WITH A BAND OF SHSN ALONG IT. MVFR OR LOWER CONDITIONS WILL BE POSSIBLE WITH THIS BAND. BEST CHANCE FOR IFR CONDITIONS WILL BE ACROSS THE HIGHER TERRAIN OF NRN NH AND WRN ME. WLY WINDS WILL BECOME GUSTY BEHIND COLD FNT YET AGAIN LATE MON NIGHT. LONG TERM...MAINLY VFR WITH WSW WINDS THROUGH MIDWEEK. POSSIBLE LINGERING MVFR IN SHOWERS MONDAY NIGHT INTO TUESDAY MORNING... ESPECIALLY FOR KHIE AND KLEB. MVFR OR LOWER CONDITIONS IN SNOW POSSIBLE THURSDAY NIGHT INTO FRIDAY MORNING AS A COLD FRONT CROSSES THE REGION. && .MARINE... SHORT TERM...AS SFC RIDGE AXIS CROSSES THE AREA TONIGHT WINDS WILL RELAX FOR A TIME. GALES ON THE OUTER WATERS WILL DIMINISH TO SCA CONDITIONS BEFORE 00Z...BUT SCA WILL LIKELY CONTINUE INTO TOMORROW. SCA IN THE BAYS WILL BE ABLE TO COME DOWN BY 00Z AS WELL. FREEZING SPRAY WILL ALSO LINGER INTO THE EVENING BEFORE WAA EASES THE THREAT. BEHIND COLD FNT LATE MON NIGHT FREEZING SPRAY WILL AGAIN BECOME AN ISSUE. LONG TERM...SOMEWHAT GUSTY WSW FLOW WILL KEEP AT LEAST SMALL CRAFT ADVISORY CONDITIONS IN PLACE FOR THE OUTER WATERS TUESDAY AND WEDNESDAY. CONDITIONS WILL BE BORDERLINE ADVISORY FOR THE OUTER WATERS FRIDAY AS A COLD FRONT CROSSES THE WATERS. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...NONE. NH...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 7 PM EST MONDAY FOR ANZ150-152-154. && $$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1224 PM EST SUN JAN 26 2014 .UPDATE... ISSUED AT 1114 AM EST SUN JAN 26 2014 GOING FORECAST LOOKS TO BE IN DECENT SHAPE WITH SNOWFALL AMOUNTS THUS FAR FROM THE CLIPPER RUNNING A TOUCH ABOVE THE FORECAST. THUS...HAVE ONLY MADE MINOR ADJUSTMENTS TO THE SNOWFALL AMOUNTS WITH MOST LOCATIONS SEEING AN INCH OR TWO. DID ADJUST THE GROUPINGS ON THE WIND CHILL WARNINGS TO ADD SOME MENTIONS OF SNOW AND BLOWING SNOW TO THE AREAS NEAR LAKE SUPERIOR. WANTED TO INCREASE THE AWARENESS OF THE REDUCED VISIBILITIES WITH THE LAKE EFFECT SNOW AND BLOWING SNOW TONIGHT INTO MONDAY FOR THE NORTHWEST WIND LOCATIONS AS ADVISORIES MAY BE NEEDED. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 656 AM EST SUN JAN 26 2014 WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW POLAR VORTEX CENTERED OVER SRN HUDSON BAY/JAMES BAY. AROUND THE VORTEX...ONE SHORTWAVE IS SWINGING THRU THE UPPER MISSISSIPPI VALLEY. A SECOND MUCH STRONGER WAVE IS DROPPING THRU SRN MANITOBA/SRN SASKATCHEWAN. FIRST WAVE IS SPREADING AN AREA OF SNOW ACROSS MUCH OF WI/NRN IL/NRN IN. SNOW THEN EXTENDS BACK TO THE NW AHEAD OF THE STRONGER WAVE. FORCING AHEAD OF THIS WAVE IS ALREADY SUPPORTING -SN SPREADING INTO THE W HALF OF UPPER MI. STRONG WINDS OVER THE LAST 2 DAYS HAVE REALLY CHANGED THE ICE COVER ON LAKE SUPERIOR...AND THIS WILL BE A COMPLICATING FACTOR AS ICE COVER IN THE MODELS IS NOT REPRESENTATIVE OF THE CURRENT STATE OF ICE. THUS...MODELS WILL BE INCORRECTLY HANDLING WINDS/CONVERGENCE/LAKE EFFECT PCPN. THE ICE COVER THAT WAS ROUGHLY BTWN MANITOU ISLAND AND SHOT POINT WEST TO KEWEENAW BAY IS CLEARLY BROKEN UP ENOUGH TO ALLOW DECENT HEAT/MOISTURE FLUXES AS WAS EVIDENT FROM THE SIGNIFICANT LES BANDS THAT STREAMED INTO MARQUETTE/WRN ALGER COUNTIES YESTEDAY. OVER WRN LAKE SUPERIOR...THERE IS PLENTY OF OPEN WATER. A BIG PORTION OF THE ICE THAT WAS OVER WRN LAKE SUPERIOR APPEARS TO BE OVER NCNTRL LAKE SUPERIOR NOW. NOT MUCH HAS CHANGED WITH THE OVERALL FCST THINKING SINCE YESTERDAY. IMPRESSIVE DEEP LAYER FORCING WILL SPREAD ACROSS UPPER MI TODAY AS SHORTWAVE SWINGS INTO THE WRN LAKES. THERE`S NOT A LOT OF MOISTURE TO WORK WITH AS MIXING RATIOS IN THE 700-750MB LAYER ARE ONLY 0.5 TO 1G/KG. ANOTHER NEGATIVE FOR SNOW ACCUMULATIONS IS LOW SNOW TO WATER RATIOS WITH DGZ NEAR THE SFC. SIMILAR TO PREVIOUS FCSTS...EXPECT A GENERAL 1-2 INCH SNOWFALL TODAY. SMALL SNOWFLAKES WILL PROBABLY MAKE FOR LOWER VIS THAN ONE WOULD EXPECT WITH LIGHT ACCUMULATIONS. WHILE 850MB WINDS BACK ENOUGH FOR LAKE ENHANCEMENT POTENTIAL OFF LAKE MICHIGAN...AT LOWER LEVELS...WINDS REMAIN OFFSHORE AS MESOLOW DEVELOPMENT OCCURS OVER NRN LAKE MICHIGAN. AT THIS POINT...NOT EXPECTING MUCH ENHANCMENT NEAR LAKE MICHIGAN. THERE SHOULD BE SOME LAKE ENHANCEMENT NEAR LAKE SUPERIOR THIS EVENING AS WINDS SHIFT N TO NW AND STRENGTHEN WITH EXTREMELY COLD AIR SURGING INTO THE AREA BEHIND SHORTWAVE. GIVEN THE OPEN WATER...SNOW MAY BE HEAVIER THAN EXPECTED OVER THE W. EVEN SO...WITH DGZ ELIMINATED BY COLD AIR...LOW SNOW TO WATER RATIOS WILL WORK AGAINST SIGNIFICANT ACCUMULATIONS. MORE CRITICAL PART OF THE FCST IS WHAT HAPPENS OVER ERN LAKE SUPERIOR. DIMINISHING GRADIENT WIND FIELD AND STRENGTHENING LAND BREEZES ARE CURRENTLY LEADING TO MESOLOW DEVELOPMENT OVER SE LAKE SUPERIOR PER SFC/MARINE OBS. WITH STRONG FORCING PROVIDED BY SHORTWAVE...MESOLOW SHOULD REALLY SPIN UP TODAY AS IT DRIFTS N OR NW. ALL HIGH RES MODEL GUIDANCE CONTINUE TO SHOW THIS...BUT TREND HAS BEEN FOR A MORE EWD TRACK AS THE LOW HEADS BACK S WITH SHORTWAVE PASSAGE LATE AFTN/EVENING. CONSENSUS IS GENERALLY FOR LANDFALL NEAR GRAND MARAIS. A BAND OF HVY LES IS EXPECTED ON THE WRN FLANK OF THE LOW...AND MODEL GUIDANCE IS MOSTLY INDICATING THIS BAND AFFECTING THE AREA BTWN MUNISING AND GRAND MARAIS. HOWEVER...WITH MODEL ICE COVER TOO EXTENSIVE TO THE LEE OF THE KEWEENAW...WOULD EXPECT SIGNIFICANT LES TO IMPACT AREAS FARTHER W IN ALGER COUNTY EVEN IF LOW IN FACT DOES MOVE ONSHORE NEAR GRAND MARAIS. HIGH RES MODEL GUIDANCE IS IN EXCELLENT AGREEMENT ON A CORE OF STRONG LOW-LEVEL WINDS (950MB WINDS OF 40-50KT) ON THE WRN SIDE OF THE LOW AIMED TOWARD THE MUNISING AREA. COMBINED WITH MESOSCALE PRES RISE/FALL COUPLET...CONDITIONS LOOK FAVORABLE FOR BLIZZARD CONDITIONS IN ALGER COUNTY TONIGHT...ESPECIALLY BTWN DEERTON AND MUNISING. HAVE THUS CONVERTED BLIZZARD WATCH TO WARNING FOR ALGER COUNTY...AND ISSUED LES ADVY FOR NRN SCHOOLCRAFT WHERE WINDS FARTHER INLAND WON`T BE NEARLY AS SIGNIFICANT. WRN EDGE OF STRONGER WIND FIELD WILL CLIP KEWEENAW COUNTY...SO ALSO ISSUED LES ADVY THERE TONIGHT/MON MORNING FOR CONSIDERABLE BLSN THOUGH SNOW ACCUMULATIONS WILL ONLY BE 2-3 INCHES. DURING THE DAY...WILL NEED TO TAKE ANOTHER LOOK AT EXPANDING ADVY OVER WRN UPPER MI AS SUFFICIENT OPEN WATER EXISTS TO LEAD TO WIDESPREAD -SHSN WHICH WILL PRODUCE VERY LOW VIS WHEN COMBINED WITH OCNL BLSN. ELSEWHERE...CONVERTED WIND CHILL WATCH TO WARNING LATE TONIGHT AS WIND CHILLS DROP TO NEAR OR BLO -35F. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 526 AM EST SUN JAN 26 2014 PRIMARY FOCUS IN THE LONG TERM IS ON THE FIRST 2 DAYS /THROUGH TUESDAY/. FOR MON...AT 12Z THE CWA WILL BE BETWEEN A CLIPPER SYSTEM OVER FAR SERN ONTARIO AND AN UPPER TROUGH OVER NWRN LAKE SUPERIOR. AT THE SFC...THE PRESSURE GRADIENT WILL BE SHARP AS THE CLIPPER LOW DEPARTS THE REGION AND A 1040MB HIGH MOVES INTO THE NRN PLAINS STATES...AND HIGH RES MODEL INDICATE A MESO LOW OVER ERN LAKE SUPERIOR MON MORNING. ALONG THE W SIDE OF THE POSSIBLE MESO LOW WILL BE VERY STRONG WINDS AND A STRONG LES BAND THAT LOOKS TO BE OVER ALGER COUNTY. HIGH RES MODELS SHOW 925MB WINDS OF 40-50KTS W OF THE MESO LOW...WHICH WOULD CONTINUE TO LEAD TO BLIZZARD CONDITIONS FROM MON NIGHT /SEE SHORT TERM DISCUSSION/ INTO MON MORNING. BY 18Z MON...THE UPPER TROUGH IS OVER ERN LAKE SUPERIOR AND HIGH RES MODELS SHOW THE MESO LOW SHIFTING TO THE E...CAUSING THE PRESSURE GRADIENT TO WEAKEN AND NW WINDS THAT WERE AHEAD OF THE TROUGH TO BECOME MORE WLY BEHIND THE TROUGH. THIS WILL SHIFT LES WHILE WEAKENING IT DUE TO THE UPPER LEVEL SUPPORT MOVING OUT. WITH THE WORST CONDITIONS FROM THE WINDS AND SNOW MORE FOCUSED DURING SUN NIGHT /SHORT TERM FORECAST/...WILL TALK ABOUT THE COLD TEMPS FOR MON INTO MON NIGHT. 850MB TEMPS WILL BE -30C TO -35C FROM 12Z-18Z MON...WARMING TO -25C TO -30C BY 00Z TUE. THIS WILL LEAD TO HIGH TEMPS ON MON OF AROUND 0F E TO AROUND -10F WEST WITH WIND CHILLS AS LOW AS -40F /COLDEST OVER THE W HALF IN THE MORNING TO EARLY AFTERNOON/. WITH WINDS SHIFTING A LITTLE MORE WLY MON NIGHT WHILE THE COLD 850MB TEMPS AROUND -25C...CLOUDS WILL BE MORE SPARSE OVER THE INTERIOR W AND CENTRAL U.P. MON NIGHT. THIS SHOULD LEAD TO LOW TEMPS AROUND -25F OVER THE WELL INTERIOR W...WHERE WINDS WILL BE AOB 10KTS. CLOSER TO LAKE SUPERIOR...LOWS WILL BE IN THE SINGLE DIGITS TO TEENS BELOW ZERO WITH WINDS TO 15-25KTS. VERY COLD WIND CHILLS WILL CONTINUE MON NIGHT THROUGH TUE MORNING. WIND CHILLS VALUES ARE EXPECTED TO FALL TO -30F TO -45F DURING THIS TIME. LES WILL CONTINUE MON NIGHT...BUT FOR MORE WNW FAVORED SNOW BELTS. WITH WINDS REMAINING GUSTY NEAR LAKE SUPERIOR...BLOWING AND DRIFTING SNOW WILL CONTINUE. WINDS LOOK TO CONTINUE TO BARELY SHIFT MORE WLY ON TUE AS THE SFC HIGH MOVES INTO THE MID MISSISSIPPI VALLEY WHILE 850MB TEMPS INCREASE TO -20C TO -25C. THIS WILL LEAD TO CONTINUE LES IN WNW WIND SNOWBELTS. WINDS NEAR LAKE SUPERIOR ON TUE SHOULD GUST TO 30-35KTS...CONTINUING BLOWING AND DRIFTING SNOW. AFTER TUE...A CLIPPER SYSTEM MAY IMPACT THE REGION LATE WED INTO THU...WITH DETAILS OF THIS SYSTEM STILL BEING SOMEWHAT UNCERTAIN. WILL FOCUS ATTENTION TO FIRST COUPLE OF DAYS OF THE LONG TERM GIVEN IMPACTS DURING THIS PERIOD...AND USE A CONSENSUS OF GUIDANCE FOR FORECASTS DURING THE LATER HALF OF THE LONG TERM. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 1223 PM EST SUN JAN 26 2014 A CLIPPER SYSTEM MOVING THROUGH THE UPPER GREAT LAKES WILL CONTINUE TO BRING LIGHT...BUT GOOD VISIBILITY RESTRICTING...SNOWFALL TO UPPER MICHIGAN EARLY THIS AFTERNOON. AS THE CLIPPER SHIFTS EAST OF THE AREA THROUGH THE REST OF THE AFTERNOON AND TONIGHT...WINDS WILL QUICKLY SHIFT TO THE NORTH-NORTHWEST AND BECOME GUSTY. THE COMBINATION OF THE GUSTY WINDS AND LAKE EFFECT SNOW WILL LEAD TO IFR OR LOWER CONDITIONS AT ALL THREE SITES TONIGHT. THINK THE WORST CONDITIONS WILL BE AT KCMX TONIGHT THROUGH MONDAY AS THEY WILL TURN TO A FAVORABLE WIND DIRECTION FOR THE FINE FLAKE SNOW AND BLOWING SNOW TO LEAD TO AIRFIELD LANDING MINS. COULD ALSO SEE BRIEF PERIODS OF SIMILAR CONDITIONS AT KIWD THIS EVENING INTO THE EARLY OVERNIGHT HOURS WHEN WINDS ARE THE STRONGEST. KSAW IS A LITTLE MORE UNCERTAIN ON THE EXACT CONDITIONS LATE THIS EVENING AND TONIGHT...AS IT DEPENDS ON THE LOCATION OF THE MESO-LOW BEING PULLED SOUTH OVER EASTERN LAKE SUPERIOR. THE HEAVIEST SNOW WILL STAY FAR TO THE EAST OF THE SITE...BUT COULD SEE NORTH-NORTHWEST WIND LAKE EFFECT INITIALLY BEFORE WINDS BACK TO OFF/ON LAKE EFFECT SNOW WITH NORTHWEST WINDS. SINCE IT WILL BE GUSTY...HAVE HELD ONTO LOWER VISIBILITIES AS CONDITIONS WILL BE SIMILAR TO YESTERDAY AFTERNOON WITH THEM BOUNCING BETWEEN IFR/MVFR. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 526 AM EST SUN JAN 26 2014 LOW PRESSURE SPRAWLED FROM HUDSON BAY TO QUEBEC WILL LIFT SLOWLY NEWD THROUGH MON. MEANWHILE...LOW PRESSURE OVER MINNESOTA WILL MOVE ACROSS NORTHERN LOWER MI AS IT DEEPENS THIS EVENING. IN ITS WAKE...HIGH PRESSURE OVER SASKATCHEWAN WILL SINK TO THE SE CONUS BY WED. EXPECT NW GALES TO 35 TO 40 KTS AND HEAVY FREEZING SPRAY /WHERE OPEN WATER REMAINS/ FROM SUN NIGHT THROUGH TUE UNDER THE SHARP PRESSURE GRADIENT BETWEEN THIS HIGH AND THE LOW IN QUEBEC. THE GALES AND HEAVY FREEZING SPRAY WILL SUBSIDE ON WED WITH THE ARRIVAL OF A WEAK HIGH PRESSURE RIDGE/FLATTER PRESSURE GRADIENT. LOW PRESSURE WILL MOVE FROM MANITOBA TO JAMES BAY ON THU...DRAGGING A LOW PRESSURE TROUGH ACROSS THE GREAT LAKES. MORE HEAVY FREEZING SPRAY MAY DEVELOP ON WED NIGHT AND THU UNDER THE SHARPER PRESSURE GRADIENT ASSOCIATED WITH THIS TROUGH PASSAGE. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... WIND CHILL WARNING FROM 1 AM EST /MIDNIGHT CST/ MONDAY TO 1 PM EST /NOON CST/ TUESDAY FOR MIZ001>005-009>013-084. LAKE EFFECT SNOW ADVISORY FROM 8 PM THIS EVENING TO NOON EST MONDAY FOR MIZ085. LAKE EFFECT SNOW ADVISORY FROM 7 PM THIS EVENING TO NOON EST MONDAY FOR MIZ001. BLIZZARD WARNING FROM 8 PM THIS EVENING TO NOON EST MONDAY FOR MIZ006. WIND CHILL WARNING FROM 7 AM MONDAY TO 1 PM EST TUESDAY FOR MIZ014. LAKE SUPERIOR... HEAVY FREEZING SPRAY WARNING UNTIL 7 AM EST WEDNESDAY FOR LSZ244- 245-264>267. GALE WARNING FROM 7 PM THIS EVENING TO 1 AM EST WEDNESDAY FOR LSZ249-250-266. GALE WARNING FROM 7 PM THIS EVENING TO 10 PM EST TUESDAY FOR LSZ244-245-248-264-265. LAKE MICHIGAN... NONE. && $$ UPDATE...SRF SHORT TERM...ROLFSON LONG TERM...TITUS AVIATION...SRF MARINE...TITUS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1115 AM EST SUN JAN 26 2014 .UPDATE... ISSUED AT 1114 AM EST SUN JAN 26 2014 GOING FORECAST LOOKS TO BE IN DECENT SHAPE WITH SNOWFALL AMOUNTS THUS FAR FROM THE CLIPPER RUNNING A TOUCH ABOVE THE FORECAST. THUS...HAVE ONLY MADE MINOR ADJUSTMENTS TO THE SNOWFALL AMOUNTS WITH MOST LOCATIONS SEEING AN INCH OR TWO. DID ADJUST THE GROUPINGS ON THE WIND CHILL WARNINGS TO ADD SOME MENTIONS OF SNOW AND BLOWING SNOW TO THE AREAS NEAR LAKE SUPERIOR. WANTED TO INCREASE THE AWARENESS OF THE REDUCED VISIBILITIES WITH THE LAKE EFFECT SNOW AND BLOWING SNOW TONIGHT INTO MONDAY FOR THE NORTHWEST WIND LOCATIONS AS ADVISORIES MAY BE NEEDED. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 656 AM EST SUN JAN 26 2014 WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW POLAR VORTEX CENTERED OVER SRN HUDSON BAY/JAMES BAY. AROUND THE VORTEX...ONE SHORTWAVE IS SWINGING THRU THE UPPER MISSISSIPPI VALLEY. A SECOND MUCH STRONGER WAVE IS DROPPING THRU SRN MANITOBA/SRN SASKATCHEWAN. FIRST WAVE IS SPREADING AN AREA OF SNOW ACROSS MUCH OF WI/NRN IL/NRN IN. SNOW THEN EXTENDS BACK TO THE NW AHEAD OF THE STRONGER WAVE. FORCING AHEAD OF THIS WAVE IS ALREADY SUPPORTING -SN SPREADING INTO THE W HALF OF UPPER MI. STRONG WINDS OVER THE LAST 2 DAYS HAVE REALLY CHANGED THE ICE COVER ON LAKE SUPERIOR...AND THIS WILL BE A COMPLICATING FACTOR AS ICE COVER IN THE MODELS IS NOT REPRESENTATIVE OF THE CURRENT STATE OF ICE. THUS...MODELS WILL BE INCORRECTLY HANDLING WINDS/CONVERGENCE/LAKE EFFECT PCPN. THE ICE COVER THAT WAS ROUGHLY BTWN MANITOU ISLAND AND SHOT POINT WEST TO KEWEENAW BAY IS CLEARLY BROKEN UP ENOUGH TO ALLOW DECENT HEAT/MOISTURE FLUXES AS WAS EVIDENT FROM THE SIGNIFICANT LES BANDS THAT STREAMED INTO MARQUETTE/WRN ALGER COUNTIES YESTEDAY. OVER WRN LAKE SUPERIOR...THERE IS PLENTY OF OPEN WATER. A BIG PORTION OF THE ICE THAT WAS OVER WRN LAKE SUPERIOR APPEARS TO BE OVER NCNTRL LAKE SUPERIOR NOW. NOT MUCH HAS CHANGED WITH THE OVERALL FCST THINKING SINCE YESTERDAY. IMPRESSIVE DEEP LAYER FORCING WILL SPREAD ACROSS UPPER MI TODAY AS SHORTWAVE SWINGS INTO THE WRN LAKES. THERE`S NOT A LOT OF MOISTURE TO WORK WITH AS MIXING RATIOS IN THE 700-750MB LAYER ARE ONLY 0.5 TO 1G/KG. ANOTHER NEGATIVE FOR SNOW ACCUMULATIONS IS LOW SNOW TO WATER RATIOS WITH DGZ NEAR THE SFC. SIMILAR TO PREVIOUS FCSTS...EXPECT A GENERAL 1-2 INCH SNOWFALL TODAY. SMALL SNOWFLAKES WILL PROBABLY MAKE FOR LOWER VIS THAN ONE WOULD EXPECT WITH LIGHT ACCUMULATIONS. WHILE 850MB WINDS BACK ENOUGH FOR LAKE ENHANCEMENT POTENTIAL OFF LAKE MICHIGAN...AT LOWER LEVELS...WINDS REMAIN OFFSHORE AS MESOLOW DEVELOPMENT OCCURS OVER NRN LAKE MICHIGAN. AT THIS POINT...NOT EXPECTING MUCH ENHANCMENT NEAR LAKE MICHIGAN. THERE SHOULD BE SOME LAKE ENHANCEMENT NEAR LAKE SUPERIOR THIS EVENING AS WINDS SHIFT N TO NW AND STRENGTHEN WITH EXTREMELY COLD AIR SURGING INTO THE AREA BEHIND SHORTWAVE. GIVEN THE OPEN WATER...SNOW MAY BE HEAVIER THAN EXPECTED OVER THE W. EVEN SO...WITH DGZ ELIMINATED BY COLD AIR...LOW SNOW TO WATER RATIOS WILL WORK AGAINST SIGNIFICANT ACCUMULATIONS. MORE CRITICAL PART OF THE FCST IS WHAT HAPPENS OVER ERN LAKE SUPERIOR. DIMINISHING GRADIENT WIND FIELD AND STRENGTHENING LAND BREEZES ARE CURRENTLY LEADING TO MESOLOW DEVELOPMENT OVER SE LAKE SUPERIOR PER SFC/MARINE OBS. WITH STRONG FORCING PROVIDED BY SHORTWAVE...MESOLOW SHOULD REALLY SPIN UP TODAY AS IT DRIFTS N OR NW. ALL HIGH RES MODEL GUIDANCE CONTINUE TO SHOW THIS...BUT TREND HAS BEEN FOR A MORE EWD TRACK AS THE LOW HEADS BACK S WITH SHORTWAVE PASSAGE LATE AFTN/EVENING. CONSENSUS IS GENERALLY FOR LANDFALL NEAR GRAND MARAIS. A BAND OF HVY LES IS EXPECTED ON THE WRN FLANK OF THE LOW...AND MODEL GUIDANCE IS MOSTLY INDICATING THIS BAND AFFECTING THE AREA BTWN MUNISING AND GRAND MARAIS. HOWEVER...WITH MODEL ICE COVER TOO EXTENSIVE TO THE LEE OF THE KEWEENAW...WOULD EXPECT SIGNIFICANT LES TO IMPACT AREAS FARTHER W IN ALGER COUNTY EVEN IF LOW IN FACT DOES MOVE ONSHORE NEAR GRAND MARAIS. HIGH RES MODEL GUIDANCE IS IN EXCELLENT AGREEMENT ON A CORE OF STRONG LOW-LEVEL WINDS (950MB WINDS OF 40-50KT) ON THE WRN SIDE OF THE LOW AIMED TOWARD THE MUNISING AREA. COMBINED WITH MESOSCALE PRES RISE/FALL COUPLET...CONDITIONS LOOK FAVORABLE FOR BLIZZARD CONDITIONS IN ALGER COUNTY TONIGHT...ESPECIALLY BTWN DEERTON AND MUNISING. HAVE THUS CONVERTED BLIZZARD WATCH TO WARNING FOR ALGER COUNTY...AND ISSUED LES ADVY FOR NRN SCHOOLCRAFT WHERE WINDS FARTHER INLAND WON`T BE NEARLY AS SIGNIFICANT. WRN EDGE OF STRONGER WIND FIELD WILL CLIP KEWEENAW COUNTY...SO ALSO ISSUED LES ADVY THERE TONIGHT/MON MORNING FOR CONSIDERABLE BLSN THOUGH SNOW ACCUMULATIONS WILL ONLY BE 2-3 INCHES. DURING THE DAY...WILL NEED TO TAKE ANOTHER LOOK AT EXPANDING ADVY OVER WRN UPPER MI AS SUFFICIENT OPEN WATER EXISTS TO LEAD TO WIDESPREAD -SHSN WHICH WILL PRODUCE VERY LOW VIS WHEN COMBINED WITH OCNL BLSN. ELSEWHERE...CONVERTED WIND CHILL WATCH TO WARNING LATE TONIGHT AS WIND CHILLS DROP TO NEAR OR BLO -35F. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 526 AM EST SUN JAN 26 2014 PRIMARY FOCUS IN THE LONG TERM IS ON THE FIRST 2 DAYS /THROUGH TUESDAY/. FOR MON...AT 12Z THE CWA WILL BE BETWEEN A CLIPPER SYSTEM OVER FAR SERN ONTARIO AND AN UPPER TROUGH OVER NWRN LAKE SUPERIOR. AT THE SFC...THE PRESSURE GRADIENT WILL BE SHARP AS THE CLIPPER LOW DEPARTS THE REGION AND A 1040MB HIGH MOVES INTO THE NRN PLAINS STATES...AND HIGH RES MODEL INDICATE A MESO LOW OVER ERN LAKE SUPERIOR MON MORNING. ALONG THE W SIDE OF THE POSSIBLE MESO LOW WILL BE VERY STRONG WINDS AND A STRONG LES BAND THAT LOOKS TO BE OVER ALGER COUNTY. HIGH RES MODELS SHOW 925MB WINDS OF 40-50KTS W OF THE MESO LOW...WHICH WOULD CONTINUE TO LEAD TO BLIZZARD CONDITIONS FROM MON NIGHT /SEE SHORT TERM DISCUSSION/ INTO MON MORNING. BY 18Z MON...THE UPPER TROUGH IS OVER ERN LAKE SUPERIOR AND HIGH RES MODELS SHOW THE MESO LOW SHIFTING TO THE E...CAUSING THE PRESSURE GRADIENT TO WEAKEN AND NW WINDS THAT WERE AHEAD OF THE TROUGH TO BECOME MORE WLY BEHIND THE TROUGH. THIS WILL SHIFT LES WHILE WEAKENING IT DUE TO THE UPPER LEVEL SUPPORT MOVING OUT. WITH THE WORST CONDITIONS FROM THE WINDS AND SNOW MORE FOCUSED DURING SUN NIGHT /SHORT TERM FORECAST/...WILL TALK ABOUT THE COLD TEMPS FOR MON INTO MON NIGHT. 850MB TEMPS WILL BE -30C TO -35C FROM 12Z-18Z MON...WARMING TO -25C TO -30C BY 00Z TUE. THIS WILL LEAD TO HIGH TEMPS ON MON OF AROUND 0F E TO AROUND -10F WEST WITH WIND CHILLS AS LOW AS -40F /COLDEST OVER THE W HALF IN THE MORNING TO EARLY AFTERNOON/. WITH WINDS SHIFTING A LITTLE MORE WLY MON NIGHT WHILE THE COLD 850MB TEMPS AROUND -25C...CLOUDS WILL BE MORE SPARSE OVER THE INTERIOR W AND CENTRAL U.P. MON NIGHT. THIS SHOULD LEAD TO LOW TEMPS AROUND -25F OVER THE WELL INTERIOR W...WHERE WINDS WILL BE AOB 10KTS. CLOSER TO LAKE SUPERIOR...LOWS WILL BE IN THE SINGLE DIGITS TO TEENS BELOW ZERO WITH WINDS TO 15-25KTS. VERY COLD WIND CHILLS WILL CONTINUE MON NIGHT THROUGH TUE MORNING. WIND CHILLS VALUES ARE EXPECTED TO FALL TO -30F TO -45F DURING THIS TIME. LES WILL CONTINUE MON NIGHT...BUT FOR MORE WNW FAVORED SNOW BELTS. WITH WINDS REMAINING GUSTY NEAR LAKE SUPERIOR...BLOWING AND DRIFTING SNOW WILL CONTINUE. WINDS LOOK TO CONTINUE TO BARELY SHIFT MORE WLY ON TUE AS THE SFC HIGH MOVES INTO THE MID MISSISSIPPI VALLEY WHILE 850MB TEMPS INCREASE TO -20C TO -25C. THIS WILL LEAD TO CONTINUE LES IN WNW WIND SNOWBELTS. WINDS NEAR LAKE SUPERIOR ON TUE SHOULD GUST TO 30-35KTS...CONTINUING BLOWING AND DRIFTING SNOW. AFTER TUE...A CLIPPER SYSTEM MAY IMPACT THE REGION LATE WED INTO THU...WITH DETAILS OF THIS SYSTEM STILL BEING SOMEWHAT UNCERTAIN. WILL FOCUS ATTENTION TO FIRST COUPLE OF DAYS OF THE LONG TERM GIVEN IMPACTS DURING THIS PERIOD...AND USE A CONSENSUS OF GUIDANCE FOR FORECASTS DURING THE LATER HALF OF THE LONG TERM. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 705 AM EST SUN JAN 26 2014 APPROACHING DISTURBANCE WILL BRING -SN TO THE AREA TODAY. DUE TO ARCTIC AIR...SNOWFLAKES WILL BE SMALL AND THUS EFFECTIVE AT REDUCING VIS. AS A RESULT...IFR SHOULD BE THE PREVAILING CONDITION AT KIWD/KCMX/KSAW TODAY...THOUGH SOME PERIODS OF MVFR ARE ALSO LIKELY. WINDS WILL BECOME NORTHERLY THIS AFTN AND INCREASE TONIGHT. COMBINATION OF -SHSN/BLSN WILL LIKELY RESULT IN LIFR CONDITIONS AT KIWD AND ESPECIALLY KCMX WHERE WINDS WILL BE STRONGER. IFR SHOULD CONTINUE AT KSAW...BUT CONDITIONS MAY FALL TO LIFR IF SNOW IS HEAVIER OR WIND STRONGER. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 526 AM EST SUN JAN 26 2014 LOW PRESSURE SPRAWLED FROM HUDSON BAY TO QUEBEC WILL LIFT SLOWLY NEWD THROUGH MON. MEANWHILE...LOW PRESSURE OVER MINNESOTA WILL MOVE ACROSS NORTHERN LOWER MI AS IT DEEPENS THIS EVENING. IN ITS WAKE...HIGH PRESSURE OVER SASKATCHEWAN WILL SINK TO THE SE CONUS BY WED. EXPECT NW GALES TO 35 TO 40 KTS AND HEAVY FREEZING SPRAY /WHERE OPEN WATER REMAINS/ FROM SUN NIGHT THROUGH TUE UNDER THE SHARP PRESSURE GRADIENT BETWEEN THIS HIGH AND THE LOW IN QUEBEC. THE GALES AND HEAVY FREEZING SPRAY WILL SUBSIDE ON WED WITH THE ARRIVAL OF A WEAK HIGH PRESSURE RIDGE/FLATTER PRESSURE GRADIENT. LOW PRESSURE WILL MOVE FROM MANITOBA TO JAMES BAY ON THU...DRAGGING A LOW PRESSURE TROUGH ACROSS THE GREAT LAKES. MORE HEAVY FREEZING SPRAY MAY DEVELOP ON WED NIGHT AND THU UNDER THE SHARPER PRESSURE GRADIENT ASSOCIATED WITH THIS TROUGH PASSAGE. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... WIND CHILL WARNING FROM 1 AM EST /MIDNIGHT CST/ MONDAY TO 1 PM EST /NOON CST/ TUESDAY FOR MIZ001>005-009>013-084. LAKE EFFECT SNOW ADVISORY FROM 8 PM THIS EVENING TO NOON EST MONDAY FOR MIZ085. LAKE EFFECT SNOW ADVISORY FROM 7 PM THIS EVENING TO NOON EST MONDAY FOR MIZ001. BLIZZARD WARNING FROM 8 PM THIS EVENING TO NOON EST MONDAY FOR MIZ006. WIND CHILL WARNING FROM 7 AM MONDAY TO 1 PM EST TUESDAY FOR MIZ014. LAKE SUPERIOR... HEAVY FREEZING SPRAY WARNING UNTIL 7 AM EST WEDNESDAY FOR LSZ244- 245-264>267. GALE WARNING FROM 7 PM THIS EVENING TO 1 AM EST WEDNESDAY FOR LSZ249-250-266. GALE WARNING FROM 7 PM THIS EVENING TO 10 PM EST TUESDAY FOR LSZ244-245-248-264-265. LAKE MICHIGAN... NONE. && $$ UPDATE...SRF SHORT TERM...ROLFSON LONG TERM...TITUS AVIATION...ROLFSON MARINE...TITUS
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1214 PM CST Sun Jan 26 2014 .SHORT TERM: (Through Late This Afternoon) Issued at 310 AM CST Sun Jan 26 2014 Big warm-up on tap for today with well-above average temps. Winds have already swung around to southerly overnight and temps have been slowly creeping upward. The warm front now extending from the surface low in north central Iowa into western MO will surge eastward across the CWA this morning as the surface low moves into the Great Lakes, with winds veering to southwest and then westerly and strong warm advection across the area. I have boosted temps from the previous forecast and am close to the last few hourly runs of the RAP which appear to have a good handle on the current temperatures here and upstream. Highs in most locations should get into the 50s. Enjoy the warmth...it ends tonight! Glass .LONG TERM: (Tonight through Saturday) Issued at 310 AM CST Sun Jan 26 2014 A powerful Arctic cold front will drive like a freight train through the CWA tonight. A strong pressure gradient and large pressure rises behind the front all point to very strong and gusty NW winds with the fropa. Have issued a wind advisory for all but southeast Missouri anticipating a 3-4 period with sustained winds of 25-35 mph and gusts of 45+. In addition to intense cold advection and plummeting temperatures, it appears that strong low level frontogenetic forcing and weak large scale ascent will produce a narrow band of snow immediately in the cold air. The band will be moving so quickly and the wind blowing so hard that any accumulations will be very light. Dangerous wind chills of 15 to 20 below zero are still on target late tonight and into Tuesday morning across northeast MO into central IL due to various combinations of the wind and bitterly cold ambient air temperatures. The previously issued wind chill advisory looks right on target for the anticipated high threat area. The bitterly cold Arctic air mass will dominate the area into Tuesday, and will be the coldest since the early January Arctic Outbreak. During the later half of the week ahead and into next weekend the upper air pattern finally breaks down. The longwave trof which has dominated eastern NOAM for weeks will weaken and shift northeastward as amplification occurs from the eastern Pacific into the western U.S. and the negative phase of the PNA pattern becomes established. There are some important differences in the deterministic model solutions during this time frame with regards to shortwave features with the developing wsw flow aloft, the location of a baroclinic zone and the depth/magnitude of cold air. This leads to greater uncertainty than normal in the details, however all guidance points to increasing precipitation chances next weekend and potential for wintery precipitation. Glass && .AVIATION: (For the 18z TAFs through 18z Monday Afternoon) Issued at 1139 AM CST Sun Jan 26 2014 VFR for the first 6 hours with gusty west winds diminishing late this afternoon. Attention then turns to the very strong arctic front which will impact all terminals tonight between 01-05z. When the front arrives, expect a sharp wind shift to the northwest and a rapid increase in both the sustained wind speed and wind gusts. Based on what`s been happening upstream, some gusts may even exceed 40 kts. In addition to bitterly cold air, scattered snow showers may also accompany the front. At this point I`m not sure whether any visibility restrictions for the first few hours after fropa would be due to falling/blowing snow, blowing dust, or both. To some extent, this may depend on the land characteristics near and upstream of each terminal, but the winds will certainly be strong enough to lift loose dirt and dust since there is no snow cover and temperatures warmed into the 40s- 50s today. Winds will gradually diminish during the day tomorrow. Specifics for KSTL: VFR for the first 6 hours with gusty west winds diminishing late this afternoon. Attention then turns to the very strong arctic front which will slam through the terminal tonight around 03-04z. When the front arrives, expect a sharp wind shift to the northwest and a rapid increase in both the sustained wind speed and wind gusts. Based on what`s been happening upstream, some gusts may even exceed 40 kts. In addition to bitterly cold air, scattered snow showers may also accompany the front. At this point I`m not sure whether any visibility restrictions for the first few hours after fropa would be due to falling/blowing snow, blowing dust, or both. Winds will gradually diminish during the day tomorrow. Kanofsky && .LSX WATCHES/WARNINGS/ADVISORIES: MO...WIND ADVISORY from 8 PM this evening to 6 AM CST Monday FOR Audrain MO-Boone MO-Callaway MO-Cole MO-Franklin MO- Gasconade MO-Jefferson MO-Knox MO-Lewis MO-Lincoln MO- Marion MO-Moniteau MO-Monroe MO-Montgomery MO-Osage MO-Pike MO-Ralls MO-Shelby MO-St. Charles MO-St. Louis City MO-St. Louis MO-Warren MO. WIND CHILL ADVISORY from 3 AM Monday to Noon CST Tuesday FOR Knox MO-Lewis MO-Marion MO-Monroe MO-Pike MO-Ralls MO- Shelby MO. IL...WIND ADVISORY from 8 PM this evening to 6 AM CST Monday FOR Adams IL-Bond IL-Brown IL-Calhoun IL-Clinton IL-Fayette IL- Greene IL-Jersey IL-Macoupin IL-Madison IL-Marion IL-Monroe IL-Montgomery IL-Pike IL-Randolph IL-St. Clair IL- Washington IL. WIND CHILL ADVISORY from 3 AM Monday to Noon CST Tuesday FOR Adams IL-Brown IL-Calhoun IL-Fayette IL-Greene IL-Jersey IL- Macoupin IL-Montgomery IL-Pike IL. && $$ WFO LSX
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1254 PM CST SUN JAN 26 2014 .UPDATE... ISSUED AT 1250 PM CST SUN JAN 26 2014 WITH OBS UPSTREAM GUSTING AT/ABOVE 58 MPH...VTN AT 63 MPH AND ANW AT 58 MPH...DECIDED TO ISSUE A HIGH WIND WARNING FOR NORTHERN PORTIONS OF THE CWA. THESE GUSTS ARE ASSOCIATED WITH THE INITIAL SURGE OF A PASSING SURFACE COLD FRONT...AND HAVE SO FAR BEEN FAIRLY SHORT LIVED...SO WENT WITH AN EXPIRATION TIME OF 6 PM THIS EVENING. WILL BE MONITORING CLOSELY IN CASE A SOUTHWARD EXPANSION IS NEEDED. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 324 AM CST SUN JAN 26 2014 TURNING WINDY AND SHARPLY COLD DURING THE SHORT TERM PERIODS. THE WEATHER PATTERN WILL BE UNDERGOING CHANGES DURING THE SHORT TERM PERIODS AS ENERGY ROTATES AROUND THE UPPER LOW IN THE VICINITY OF THE HUDSON BAY AND AND SWINGS ACROSS THE INTERIOR CONUS...ALLOWING ARCTIC AIR TO PLUNGE SOUTH ACROSS THE CENTRAL PLAINS THIS AFTERNOON AND TONIGHT. THIS WILL BRING A DRASTIC END TO OUR WARMER TEMPERATURES THE LAST COUPLE OF DAYS AS SHARPLY COLDER AIR ARRIVES ABOARD INTENSE NORTHERLY WINDS. CURRENTLY A SFC LOW PRESSURE SYSTEM WAS SLIDING EAST ACROSS IA EARLY THIS MORNING AND IN STEADY/GUSTY WESTERLY WINDS BEHIND THE SYSTEM TEMPS HAVE REMAINED MILD IN THE 40S AND 50S. AS SOME MID LEVEL WARM AIR HAS MIXED TO THE SFC THE TEMP AT ORD JUMPED TO 53 DEGREES WHICH WILL LIKELY BE THE CALENDAR DAY HIGH FOR THIS AREA TODAY. UPSTREAM...THE ARCTIC AIRMASS WAS ADVANCING SOUTH THRU CANADA TOWARDS THE DAKOTAS. THE MORNING HOURS INTO THE FIRST PART OF THE AFTERNOON WILL CONTINUE TO FEATURE MILD WEATHER WITH STEADY/GUSTY WINDS WITH WINDS TRENDING UP FURTHER BY LATE MORNING AS MIXING INCREASES/DEEPENS. THE AFTERNOON HOURS INTO THE EVENING WILL SEE THE BIGGER WEATHER CHANGES AS THE ARCTIC FRONT MOVES INTO OUR NORTHERN ZONES AROUND 21Z OR SHORTLY THEREAFTER. THE ARCTIC FRONT REACHES THE NEB/KS STATELINE BY 00Z AND CLEARS OUR CWA BY 03Z. TEMPS WILL RAPIDLY FALL IN THE ARCTIC AIRMASS N/S THIS AFTN/EVENING. MODELS CONTINUE TO PROG VERY IMPRESSIVE THREE HOUR PRESSURE RISES BEHIND THE FRONT ON THE ORDER OF 12MB. THE TIGHT PRESSURE GRADIENT...DEEP MIXING AS HIGH AS H8 WILL LEAD TO INTENSE WINDS DEVELOPING MID TO LATE AFTERNOON ACROSS OUR NORTH AND SPREADING SOUTHWARD WITH THE FRONT THIS EVENING AND TONIGHT. GIVEN THE STRONG WINDS/WIND GUSTS WILL GO AHEAD WITH A WIND ADVISORY HEADLINE BEGINNING THIS AFTERNOON AND CONTINUING INTO THE FIRST PART OF THE NIGHT UNTIL THE GRADIENT RELAXES. STILL HAVE CONCERNS FOR REACHING HIGH WIND WARNING ACROSS OUR NORTHEAST ZONES WHERE WINDS AT THE TOP OF THE MIXED LAYER PER RAP SOUNDINGS AVERAGE NEAR 50KTS AND THIS WILL NEED TO BE MONITORED CLOSELY TODAY...AND WIND ADVISORY MAY NEED TO BE UPGRADED TO WARNING IF WINDS TREND UP MUCH FURTHER. HAVE ALSO MAINTAINED AN OUTSIDE CHC FOR SPRINKLES/FLURRIES IN FRONTOGENESIS...BUT DO NOT EXPECT MUCH MORE THAN THAT WITH LLVL MOISTURE LACKING. TONIGHT...A 1040MB SFC RIDGE BUILDS SOUTHEAST FM THE DAKOTAS ONTO THE PLAINS...AND WIND SPEEDS WILL GRADUALLY DECREASE TOWARD MORNING AS THE GRADIENT RELAXES. IN THE ARCTIC AIRMASS TEMPERATURES BOTTOM OUT IN THE SINGLE DIGITS ABOVE/BELOW ZERO. THE COMBINATION OF THE COLD TEMPS IN THE ARCTIC AIR WITH THE STEADY WINDS WILL LEAD TO FRIGID WIND CHILLS AT WIND CHILL ADVISORY CRITERIA ACROSS PORTIONS OF SOUTH CENTRAL NEBRASKA. A WIND CHILL ADVISORY WILL BE POSTED FOR LOCATIONS IN NEBRASKA ALONG/NORTH OF INTERSTATE 80 WHERE THE COLDEST WIND CHILL READINGS ARE EXPECTED FOR THE LONGEST DURATION. IF TEMPS TREND LOWER OR WINDS REMAIN STRONGER FARTHER SOUTH...THIS ADVISORY MAY NEED TO BE EXPANDED. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 324 AM CST SUN JAN 26 2014 MAIN FORECAST CONCERNS WILL BE WIND CHILLS EARLY MONDAY MORNING...CHANCES FOR SNOW WEDNESDAY NIGHT AND AGAIN FRIDAY THROUGH SATURDAY AND TEMPERATURES THROUGH THE PERIOD. WINDS AND COLD TEMPERATURES WILL CONTINUE TO BRING WIND CHILL READINGS DOWN TO AROUND 20 BELOW EARLY MONDAY MORNING. A COLD SURFACE HIGH PRESSURE PUSHES INTO THE CENTRAL PLAINS MONDAY THROUGH TUESDAY. THE CENTER OF THE HIGH SHOULD REMAIN TO THE EAST OF THE FORECAST AREA SO THE WINDS WILL CONTINUE AS WELL AS THE COLD TEMPERATURES. WIND CHILLS WILL BE AROUND 15 BELOW IN THE FAR NORTH AGAIN EARLY TUESDAY MORNING. AS THE SURFACE HIGH MOVES TO THE EAST TUESDAY NIGHT THERE IS WARM ADVECTION ACROSS THE AREA LATE TUESDAY NIGHT INTO WEDNESDAY. TEMPERATURES WILL BE THE WARMEST ON WEDNESDAY. BY WEDNESDAY NIGHT THERE IS AN UPPER LEVEL WAVE THAT MOVES THROUGH THE AREA AS WELL AS ANOTHER COLD FRONT. THERE IS A SLIGHT CHANCE FOR SOME LIGHT SNOW IN THE FAR NORTH AS THIS WAVE MOVES THROUGH. MODELS HAVE A FEW DIFFERENCES FOR THE FRIDAY TO SATURDAY TIME FRAME...BUT BOTH THE GFS AND THE ECMWF HAVE AT LEAST A LITTLE PRECIPITATION ACROSS THE AREA OFF AND ON. ANOTHER UPPER LEVEL WAVE MOVES THROUGH THE AREA AND THIS TIME THERE IS SOME MOISTURE TO WORK WITH. THE GFS HAS A LITTLE MORE PRECIPITATION THAN THE ECMWF...BUT BOTH HAVE A LITTLE. WILL KEEP SLIGHT CHANCES IN FOR FRIDAY THROUGH SATURDAY. TEMPERATURES SHOULD BE A LITTLE BELOW NORMAL AND THE PRECIPITATION SHOULD BE SNOW. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 1131 AM CST SUN JAN 26 2014 PRIMARY FORECAST CONCERN FOR THIS TAF PERIOD LIES WITH WINDS. AN UPPER LEVEL DISTURBANCE PASSING TO THE N/NE OF THE CWA WILL BE PUSHING A STRONG COLD FRONT THROUGH THE REGION THIS AFTERNOON...USHERING IN GUSTY NWRLY WINDS. SUSTAINED SPEEDS OF 30 TO NEAR 40 MPH ARE EXPECTED...AS ARE GUSTS NEAR/OVER 50 MPH. BECAUSE IT WILL TAKE A WHILE FOR THE SURFACE HIGH BEHIND THE FRONT TO SETTLE IN...GUSTY WINDS /THOUGH NOT AS HIGH AS THIS AFTERNOON AND EVENING/ WILL LINGER EVEN AFTER MIDNIGHT. NEAR/AFTER SUNRISE TOMORROW...SPEEDS CLOSER TO 15 MPH ARE EXPECTED. DECIDED TO INSERT A MENTION OF SOME LIGHT SNOW LATE THIS AFTERNOON WITH THE PASSAGE OF THE FRONT AND INITIAL SURGE OF COLDER AIR. LEFT AS A TEMPO AT THIS POINT AS MODELS NOT IN THE BEST OF AGREEMENT WITH WHETHER THE TERMINAL WOULD BE AFFECTED...AND WILL MONITOR TRENDS AS THE AFTERNOON PASSES. && .GID WATCHES/WARNINGS/ADVISORIES... NE...WIND ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR NEZ072>077-082>087. HIGH WIND WARNING UNTIL 6 PM CST THIS EVENING FOR NEZ039>041- 046>049. WIND ADVISORY FROM 6 PM THIS EVENING TO MIDNIGHT CST TONIGHT FOR NEZ039>041-046>049. WIND CHILL ADVISORY FROM 2 AM TO 10 AM CST MONDAY FOR NEZ039>041- 046>049-060>064. WIND ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR NEZ060>064. KS...WIND ADVISORY FROM 6 PM THIS EVENING TO 2 AM CST MONDAY FOR KSZ005>007-017>019. && $$ UPDATE...ADO SHORT TERM...FAY LONG TERM...JCB AVIATION...ADO
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1137 AM CST SUN JAN 26 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 324 AM CST SUN JAN 26 2014 TURNING WINDY AND SHARPLY COLD DURING THE SHORT TERM PERIODS. THE WEATHER PATTERN WILL BE UNDERGOING CHANGES DURING THE SHORT TERM PERIODS AS ENERGY ROTATES AROUND THE UPPER LOW IN THE VICINITY OF THE HUDSON BAY AND AND SWINGS ACROSS THE INTERIOR CONUS...ALLOWING ARCTIC AIR TO PLUNGE SOUTH ACROSS THE CENTRAL PLAINS THIS AFTERNOON AND TONIGHT. THIS WILL BRING A DRASTIC END TO OUR WARMER TEMPERATURES THE LAST COUPLE OF DAYS AS SHARPLY COLDER AIR ARRIVES ABOARD INTENSE NORTHERLY WINDS. CURRENTLY A SFC LOW PRESSURE SYSTEM WAS SLIDING EAST ACROSS IA EARLY THIS MORNING AND IN STEADY/GUSTY WESTERLY WINDS BEHIND THE SYSTEM TEMPS HAVE REMAINED MILD IN THE 40S AND 50S. AS SOME MID LEVEL WARM AIR HAS MIXED TO THE SFC THE TEMP AT ORD JUMPED TO 53 DEGREES WHICH WILL LIKELY BE THE CALENDAR DAY HIGH FOR THIS AREA TODAY. UPSTREAM...THE ARCTIC AIRMASS WAS ADVANCING SOUTH THRU CANADA TOWARDS THE DAKOTAS. THE MORNING HOURS INTO THE FIRST PART OF THE AFTERNOON WILL CONTINUE TO FEATURE MILD WEATHER WITH STEADY/GUSTY WINDS WITH WINDS TRENDING UP FURTHER BY LATE MORNING AS MIXING INCREASES/DEEPENS. THE AFTERNOON HOURS INTO THE EVENING WILL SEE THE BIGGER WEATHER CHANGES AS THE ARCTIC FRONT MOVES INTO OUR NORTHERN ZONES AROUND 21Z OR SHORTLY THEREAFTER. THE ARCTIC FRONT REACHES THE NEB/KS STATELINE BY 00Z AND CLEARS OUR CWA BY 03Z. TEMPS WILL RAPIDLY FALL IN THE ARCTIC AIRMASS N/S THIS AFTN/EVENING. MODELS CONTINUE TO PROG VERY IMPRESSIVE THREE HOUR PRESSURE RISES BEHIND THE FRONT ON THE ORDER OF 12MB. THE TIGHT PRESSURE GRADIENT...DEEP MIXING AS HIGH AS H8 WILL LEAD TO INTENSE WINDS DEVELOPING MID TO LATE AFTERNOON ACROSS OUR NORTH AND SPREADING SOUTHWARD WITH THE FRONT THIS EVENING AND TONIGHT. GIVEN THE STRONG WINDS/WIND GUSTS WILL GO AHEAD WITH A WIND ADVISORY HEADLINE BEGINNING THIS AFTERNOON AND CONTINUING INTO THE FIRST PART OF THE NIGHT UNTIL THE GRADIENT RELAXES. STILL HAVE CONCERNS FOR REACHING HIGH WIND WARNING ACROSS OUR NORTHEAST ZONES WHERE WINDS AT THE TOP OF THE MIXED LAYER PER RAP SOUNDINGS AVERAGE NEAR 50KTS AND THIS WILL NEED TO BE MONITORED CLOSELY TODAY...AND WIND ADVISORY MAY NEED TO BE UPGRADED TO WARNING IF WINDS TREND UP MUCH FURTHER. HAVE ALSO MAINTAINED AN OUTSIDE CHC FOR SPRINKLES/FLURRIES IN FRONTOGENESIS...BUT DO NOT EXPECT MUCH MORE THAN THAT WITH LLVL MOISTURE LACKING. TONIGHT...A 1040MB SFC RIDGE BUILDS SOUTHEAST FM THE DAKOTAS ONTO THE PLAINS...AND WIND SPEEDS WILL GRADUALLY DECREASE TOWARD MORNING AS THE GRADIENT RELAXES. IN THE ARCTIC AIRMASS TEMPERATURES BOTTOM OUT IN THE SINGLE DIGITS ABOVE/BELOW ZERO. THE COMBINATION OF THE COLD TEMPS IN THE ARCTIC AIR WITH THE STEADY WINDS WILL LEAD TO FRIGID WIND CHILLS AT WIND CHILL ADVISORY CRITERIA ACROSS PORTIONS OF SOUTH CENTRAL NEBRASKA. A WIND CHILL ADVISORY WILL BE POSTED FOR LOCATIONS IN NEBRASKA ALONG/NORTH OF INTERSTATE 80 WHERE THE COLDEST WIND CHILL READINGS ARE EXPECTED FOR THE LONGEST DURATION. IF TEMPS TREND LOWER OR WINDS REMAIN STRONGER FARTHER SOUTH...THIS ADVISORY MAY NEED TO BE EXPANDED. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 324 AM CST SUN JAN 26 2014 MAIN FORECAST CONCERNS WILL BE WIND CHILLS EARLY MONDAY MORNING...CHANCES FOR SNOW WEDNESDAY NIGHT AND AGAIN FRIDAY THROUGH SATURDAY AND TEMPERATURES THROUGH THE PERIOD. WINDS AND COLD TEMPERATURES WILL CONTINUE TO BRING WIND CHILL READINGS DOWN TO AROUND 20 BELOW EARLY MONDAY MORNING. A COLD SURFACE HIGH PRESSURE PUSHES INTO THE CENTRAL PLAINS MONDAY THROUGH TUESDAY. THE CENTER OF THE HIGH SHOULD REMAIN TO THE EAST OF THE FORECAST AREA SO THE WINDS WILL CONTINUE AS WELL AS THE COLD TEMPERATURES. WIND CHILLS WILL BE AROUND 15 BELOW IN THE FAR NORTH AGAIN EARLY TUESDAY MORNING. AS THE SURFACE HIGH MOVES TO THE EAST TUESDAY NIGHT THERE IS WARM ADVECTION ACROSS THE AREA LATE TUESDAY NIGHT INTO WEDNESDAY. TEMPERATURES WILL BE THE WARMEST ON WEDNESDAY. BY WEDNESDAY NIGHT THERE IS AN UPPER LEVEL WAVE THAT MOVES THROUGH THE AREA AS WELL AS ANOTHER COLD FRONT. THERE IS A SLIGHT CHANCE FOR SOME LIGHT SNOW IN THE FAR NORTH AS THIS WAVE MOVES THROUGH. MODELS HAVE A FEW DIFFERENCES FOR THE FRIDAY TO SATURDAY TIME FRAME...BUT BOTH THE GFS AND THE ECMWF HAVE AT LEAST A LITTLE PRECIPITATION ACROSS THE AREA OFF AND ON. ANOTHER UPPER LEVEL WAVE MOVES THROUGH THE AREA AND THIS TIME THERE IS SOME MOISTURE TO WORK WITH. THE GFS HAS A LITTLE MORE PRECIPITATION THAN THE ECMWF...BUT BOTH HAVE A LITTLE. WILL KEEP SLIGHT CHANCES IN FOR FRIDAY THROUGH SATURDAY. TEMPERATURES SHOULD BE A LITTLE BELOW NORMAL AND THE PRECIPITATION SHOULD BE SNOW. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 1131 AM CST SUN JAN 26 2014 PRIMARY FORECAST CONCERN FOR THIS TAF PERIOD LIES WITH WINDS. AN UPPER LEVEL DISTURBANCE PASSING TO THE N/NE OF THE CWA WILL BE PUSHING A STRONG COLD FRONT THROUGH THE REGION THIS AFTERNOON...USHERING IN GUSTY NWRLY WINDS. SUSTAINED SPEEDS OF 30 TO NEAR 40 MPH ARE EXPECTED...AS ARE GUSTS NEAR/OVER 50 MPH. BECAUSE IT WILL TAKE A WHILE FOR THE SURFACE HIGH BEHIND THE FRONT TO SETTLE IN...GUSTY WINDS /THOUGH NOT AS HIGH AS THIS AFTERNOON AND EVENING/ WILL LINGER EVEN AFTER MIDNIGHT. NEAR/AFTER SUNRISE TOMORROW...SPEEDS CLOSER TO 15 MPH ARE EXPECTED. DECIDED TO INSERT A MENTION OF SOME LIGHT SNOW LATE THIS AFTERNOON WITH THE PASSAGE OF THE FRONT AND INITIAL SURGE OF COLDER AIR. LEFT AS A TEMPO AT THIS POINT AS MODELS NOT IN THE BEST OF AGREEMENT WITH WHETHER THE TERMINAL WOULD BE AFFECTED...AND WILL MONITOR TRENDS AS THE AFTERNOON PASSES. && .GID WATCHES/WARNINGS/ADVISORIES... NE...WIND ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR NEZ072>077-082>087. WIND ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR NEZ039>041-046>049- 060>064. WIND CHILL ADVISORY FROM 2 AM TO 10 AM CST MONDAY FOR NEZ039>041- 046>049-060>064. KS...WIND ADVISORY FROM 6 PM THIS EVENING TO 2 AM CST MONDAY FOR KSZ005>007-017>019. && $$ SHORT TERM...FAY LONG TERM...JCB AVIATION...ADO
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1131 AM CST SUN JAN 26 2014 .SHORT TERM...(TODAY THROUGH TUESDAY) ISSUED AT 253 AM CST SUN JAN 26 2014 ...VERY WINDY THIS AFTERNOON AND EVENING THEN BITTER COLD LATE TONIGHT AND EARLY MONDAY... FAIRLY COMPLEX FORECAST SETTING UP THROUGH THE SHORT TERM AS THE NEXT IN A SERIES OF ARCTIC FRONTS SWEEPS ACROSS THE REGION THIS AFTERNOON. THE CLIPPER SYSTEM THAT MOVED TO OUR NORTH AND EAST EARLIER THIS MORNING HAS LEFT US WITHIN A VERY MILD REGIME WITH TEMPS EARLY THIS MORNING SIGNIFICANTLY WARMER THAN PREVIOUSLY THOUGHT IN THE 40S TO NEAR 50. WHILE TEMPS WILL COOL A BIT THROUGH DAYBREAK...IT`S GOING TO BE ON THE MILD SIDE AHEAD OF THE ARCTIC FRONT. ARRIVAL OF ARCTIC FRONT IS STILL ON SCHEDULE...MOVING INTO NORTHEAST NEBRASKA 18-21Z...AND THE REMAINDER OF THE REGION 21-00Z. HAVE NO DOUBT WE`LL MEET WIND ADVISORY CRITERIA TODAY...THE BIG QUESTION IS IF WIND GUSTS WILL BE STRONG ENOUGH TO MEET HIGH WIND WARNING CRITERIA...AS THEY HAVE WITH SEVERAL PREVIOUS FRONTS OVER THE LAST COUPLE OF WEEKS. SOUNDINGS STILL SUGGEST THAT WE`LL MIX VERY DEEP WITH THE ARRIVAL OF THE ARCTIC AIR UP TO 750/725 MB. WINDS AT THIS LEVEL WILL BE QUITE STRONG AT 60 TO 70 KNOTS. NAM AND RAP ARE THE MOST AGGRESSIVE WITH THE WIND GUST POTENTIAL BOTH SUGGESTING THAT SURFACE WINDS COULD GUST TO 50 KNOTS OR SLIGHTLY HIGHER. OTHER MODEL SUITES AREN`T QUITE AS STRONG. COMPOUNDING THE ARRIVAL OF THE WINDS...THERE COULD BE SCATTERED SHOWERS THAT DEVELOP...INITIALLY RAIN AND THEN SNOW...WHICH WILL HELP WITH MOMENTUM TRANSFER TO THE SURFACE. NAM DOESN`T DEVELOP MUCH PRECIPITATION...BUT NEARLY ALL OTHER MODEL SUITES DO. THERE IS SOME CONCERN THAT A CONVECTIVE SNOW BAND COULD DEVELOP WITH THE SURGE OF COLDER AIR...ESPECIALLY SHOWN BY 03Z HOPWRF RUNS. WILL HAVE TO MONITOR FOR ANY VISIBILITY DROPS ONCE THE PRECIP CHANGES TO SNOW AS WELL...AND WHETHER THERE COULD BE THE POTENTIAL FOR A QUICK HALF INCH OF SNOW IN NORTHEAST NEBRASKA AND WESTERN IOWA. HAVE OPTED TO CONVERT THE HIGH WIND WATCH INTO A HIGH WIND WARNING ALONG AND NORTH OF I80. STRONG WINDS CONTINUE INTO SUNDAY EVENING...THUS WILL HAVE AN ADVISORY FOR THE REMAINING COUNTIES... WHERE MOMENTUM MIXING MAY NOT BE AS STRONG SINCE THE SUN WILL HAVE SET BY THEN. HIGH WIND WARNING COULD EVENTUALLY BE CONVERTED INTO A WIND ADVISORY AS SEVERE GUST POTENTIAL SUBSIDES THROUGH THE EVENING...BUT WOULD BEST BE MANAGED IN THE VERY NEAR TERM WITH UPDATES BASED ON REAL TIME REPORTS. SECONDARY IMMEDIATE CONCERN FOR LATER SUNDAY NIGHT INTO EARLY MONDAY IS THE ARRIVAL OF VERY COLD TEMPS BEHIND THE ARCTIC FRONT. READINGS SHOULD DROP INTO THE SINGLE DIGITS ABOVE AND BELOW ZERO...SIMILAR TO THE ARCTIC SURGE OF LAST WEEK. WHEN COUPLED WITH WINDS STILL IN THE 10-15 MPH RANGE...THIS WILL PRODUCE WIND CHILL VALUES OF 20 TO 29 BELOW THROUGH MONDAY MORNING ALONG AND NORTH OF I80 AND ACROSS MOST OF SOUTHWEST IOWA. THUS WILL HAVE A WIND CHILL ADVISORY IN EFFECT. SURFACE HIGH PRESSURE RIDGE REMAINS ACROSS THE REGION THROUGH TUESDAY. THIS WILL RESULT IN A VERY COLD DAY MONDAY...AND SUB ZERO READINGS AGAIN MONDAY NIGHT. WINDS WILL BE LIGHTER THAN MONDAY MORNING...BUT BECAUSE IT`S COLDER...WIND CHILL VALUES WILL AGAIN DROP TO 20 TO 28 BELOW OVER SOME PARTS OF THE FORECAST AREA. STILL A COLD DAY TUESDAY. .LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY) ISSUED AT 253 AM CST SUN JAN 26 2014 FORECAST PROBLEMS WITH THE EXTENDED INVOLVE ANOTHER FRONT THAT MOVES THROUGH THE REGION WEDNESDAY NIGHT. AHEAD OF THE FRONT...DECENT POTENTIAL TO WARM BACK INTO THE 30S...THEN COLDER BEHIND IT ON THURSDAY. STILL LOOKS LIKE A SMALL CHANCE OF LIGHT SNOW WEDNESDAY NIGHT. AND STILL SOME SMALL POTENTIAL THAT IT COULD LINGER INTO THURSDAY MORNING...BUT WILL WAIT FOR ANOTHER SET OF MODEL RUNS TO FINE TUNE THAT. BIGGER CONCERN IS SETTING UP FOR FRIDAY AND SATURDAY. THE GFS IS PAINTING A FAIRLY ROBUST WAVE MOVING OUT OF THE ROCKIES GIVING US A PRETTY CHANCE OF SNOW. THE ECMWF ALSO HAVE A WAVE...BUT IS A LITTLE BIT SLOWER AND WOULD HOLD OFF UNTIL FRIDAY NIGHT. AGAIN... WILL NEED TO WAIT FOR ANOTHER DAY OF MODEL RUNS TO FINE TUNE THIS...BUT IT APPEARS THAT SNOW CHANCES MAY BE INCREASING LATE IN THE WEEK. && .AVIATION...(18Z TAFS FOR KOFK...KLNK AND KOMA.) ISSUED AT 1117 AM CST SUN JAN 26 2014 COUPLE ISSUES OF INTEREST DURING THE FCST PD. FIRST IS BRIEF PD OF CONDITIONS DETERIORATING LATE THIS AFTN AS WELL AS GUSTY NW WINDS. RADAR TRENDS LAST COUPLE HOURS SHOWING AREA OF RETURNS OVER SD MAKING A QUICK DASH SWD WITH INCOMING ARCTIC AIRMASS. MOST LIKELY THAT PCPN TYPE WHEN IT ARRIVES AT KOFK WILL BE -SN ACCOMPANIED BY BLSN/LIFR VSBYS LATE THIS AFTN. AS FOR KOMA/KLNK...PCPN TYPE MORE PROBLEMATIC AS BRUNT OF COLD AIR MASS WILL JUST BE ARRIVING. SUSPECT PCPN TYPE AT THOSE SITES WILL BE -RA/SN MIX MAINLY LATE THIS AFTN AND MAYBE EARLY EVENING. NO SIGNIFICANT ACCUM EXPECTED AT ANY TERMINALS. NEXT...INTENSE SFC HIGH BUILDING SWD INTO THE CNTRL PLAINS WILL ALLOW WINDS TO REMAIN QUITE STRONG OUT OF THE NW WITH GUSTS AROUND 45KT THIS AFTN THEN AROUND 30KT OVERNIGHT. WINDS WILL SUBSIDE THEN BY 12Z MON MORNING. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...HIGH WIND WARNING FROM 3 PM THIS AFTERNOON TO MIDNIGHT CST TONIGHT FOR NEZ034-044-045-050>053-065>067. WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO 10 AM CST MONDAY FOR NEZ011-012-015>018-031>034. WIND ADVISORY FROM 5 PM THIS AFTERNOON TO MIDNIGHT CST TONIGHT FOR NEZ078-088>090-092. HIGH WIND WARNING FROM 5 PM THIS AFTERNOON TO MIDNIGHT CST TONIGHT FOR NEZ068-091-093. WIND CHILL ADVISORY FROM 3 AM TO 10 AM CST MONDAY FOR NEZ030- 042>045-050>053-065>068. HIGH WIND WARNING UNTIL MIDNIGHT CST TONIGHT FOR NEZ011-012- 015>018-030>033-042-043. IA...HIGH WIND WARNING FROM 3 PM THIS AFTERNOON TO MIDNIGHT CST TONIGHT FOR IAZ043-055-056-069-079-080. WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO 10 AM CST MONDAY FOR IAZ043-055-056. HIGH WIND WARNING FROM 5 PM THIS AFTERNOON TO MIDNIGHT CST TONIGHT FOR IAZ090-091. WIND CHILL ADVISORY FROM 3 AM TO 10 AM CST MONDAY FOR IAZ069-079- 080-090-091. && $$ SHORT TERM...DEWALD LONG TERM...DEWALD AVIATION...DEE
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
531 PM EST SUN JAN 26 2014 .SYNOPSIS... ANOTHER CLIPPER TYPE LOW WILL SLIDE OFF TO THE NORTH OF THE AREA LATER TONIGHT AND MONDAY. A TRAILING COLD FRONT WILL PASS THROUGH THE REGION MONDAY...USHERING IN YET ANOTHER BLAST OF DANGEROUSLY COLD ARCTIC AIR THAT WILL LAST MUCH OF THE UPCOMING WEEK. A GRADUAL MODERATING TREND WILL OCCUR LATER IN THE WEEK INTO SUPERBOWL WEEKEND. && .NEAR TERM /UNTIL 6 AM MONDAY MORNING/... WARM FRONT AND ASSOC BAND OF LGT OVERRUNNING SNOW IS RAPIDLY LIFTING THRU NORTHERN PA EARLY THIS EVENING. LINEAR EXTRAPOLATION AND RAP GUIDANCE BOTH SUGGEST BACK EDGE OF THE STEADY LGT SNOW WILL CLEAR THE N TIER COUNTIES BY ARND 00Z. ACCUMS OF AN INCH OR LESS HAVE BE FAIRLY COMMON ACROSS THE ALLEGHENY PLATEAU AND CENTRAL MTNS. GUIDANCE SUPPORTS DRY WX FOR MUCH OF THE NIGHT. ONLY FORCING SOUTH OF WARM FRONT WILL BE OROGRAPHIC LIFT ACROSS THE N MTNS...BUT MOISTURE SHOULD BE TOO SHALLOW TO SUPPORT ANYTHING MORE THAN A FEW FLURRIES. HOWEVER...ARRIVAL OF ARCTIC COLD FRONT WILL BE ACCOMPANIED BY SNOW SHOWERS LATE TONIGHT ACROSS THE NW MTNS AND THE CENTRAL MTNS BY ARND 12Z. BLEND OF MDL QPF IMPLIES A FRESH INCH OR SO IS LIKELY ACROSS THE NW MTNS TOWARDS DAWN. TEMPS ARE RISING ACROSS ALL OF CENTRAL PA EARLY THIS EVENING AND EXPECT THAT TREND TO CONTINUE OVERNIGHT UNDER CLOUD COVER AND WARM ADVECTION. BY 12Z TEMPS SHOULD HAVE FALLEN BACK TO THE UTEENS ACROSS THE NW MTNS BEHIND THE CDFRONT. AT THE SAME TIME...SREF AND GEFS OUTPUT SUGGEST SOME PARTS OF SOUTHERN PA MAY CREEP ABOVE THE FREEZING MARK IN SOUTHERLY FLOW AHEAD OF FRONT. && .SHORT TERM /6 AM MONDAY MORNING THROUGH 6 PM MONDAY/... THE LATEST IN WHAT HAS BEEN A MONTH OF STRONG ARCTIC FRONTS WILL BE RACING THROUGH THE AREA EARLY MONDAY. DAY TIME HIGHS WILL BE REACHED EARLY IN THE DAY...WITH THE TEMP STEADY OR FALLING THROUGHOUT THE DAY ON A GUSTY WNW WIND. BY EVENING...TEMPS WILL RANGE FROM THE SINGLE DIGITS OVER THE NW TO NEAR 20 IN HARRISBURG. WIND CHILLS WILL BE RUNNING ZERO TO 10 BELOW OVER THE LAURELS AND NRN MOUNTAINS...AND BETWEEN ZERO AND 10 ABOVE ZERO ELSEWHERE. PERIODS OF MAINLY LIGHT SNOW OR SNOW SHOWERS MONDAY WILL COINCIDE WITH THE PASSAGE OF THE UPPER LEVEL SHORT WAVE AND THE ARCTIC BOUNDARY. HAVE TRIMMED BACK THE QPF...USING A BLEND OF SREF/ECMWF/GFS AND HPC NUMBERS. THE AIRMASS WILL BE INCREDIBLY DRY AND GETTING LITTLE OR NO MOISTURE CONTRIBUTION FROM THE GR LAKES. ACCUMS OF A COATING TO AROUND 1 INCH ARE LIKELY ACROSS MAINLY THE LAURELS UP THROUGH THE NW MOUNTAINS. CONCERN IS THAT THE BOUNDARY WILL BE ACCOMPANIED BY A LINE OF SQUALLS AS DEPICTED ON THE 12Z WRF. FORECAST INSTABILITY IS NOT NEARLY AS IMPRESSIVE AS WHAT ACCOMPANIED THE FRONT THROUGH THE AREA LAST EVENING HOWEVER. && .LONG TERM /MONDAY NIGHT THROUGH SUNDAY/... ARCTIC AIR AND FLOW AROUND THE CIRCUMPOLAR VORTEX...EXPECTED TO BE CENTERED NEAR HUDSON BAY EARLY IN THE PERIOD...IS FORECAST TO DOMINATE THE EASTERN U.S. THROUGH MID WEEK. AIRFLOW OF PACIFIC ORIGIN MAY ONCE AGAIN MAKE INROADS OUR WAY LATER IN THE WEEK AS THE UPPER RIDGE OVER ALASKA IS FORECAST TO BREAK DOWN. THIS WOULD LEAD TO A MODERATION IN TEMPERATURES FOR OUR REGION...AS WELL AS A POTENTIAL INCREASE IN THE CHANCES FOR STORMINESS BY THE END OF THE LONG TERM PERIOD. AT THE SURFACE...HIGH PRESSURE WILL DOMINATE MUCH OF THE PERIOD...WITH THE FRONT LEADING THE REINFORCING SHOT OF COLD AIR THAT WILL AFFECT PA FOR MOST OF THE WEEK HAVING MOVED THROUGH RIGHT BEFORE THE START OF THE PERIOD. THUS MONDAY NIGHT THROUGH THURSDAY WILL BE BITTERLY COLD AND DRY. COLD FROPA NEXT FRIDAY MAY STALL TO THE SOUTH OF PA AND RETURN AS A WARM FRONT NEXT WEEKEND AS SRN STREAM ENERGY TRIES TO PUSH EAST. THIS MAY ALSO INCLUDE THE RETURN OF GULF OF MEXICO MOISTURE...WHICH COULD CERTAINLY BE INTERESTING IN TERMS OF PCPN AS WE HEAD TOWARD GROUNDHOGS DAY WEEKEND. && .AVIATION /22Z SUNDAY THROUGH FRIDAY/... STEADY LIGHT SNOW CAME IN REAL FAST THIS AFT...FASTER THAN WHAT I WOULD EXPECTED. ANYWAY...SOME CHANGES MADE TO 21Z TAFS. EARLIER DISCUSSION BELOW. STEADY LIGHT SNOW IS RACING INTO CENTRAL AND WESTERN PA. AS EXPECTED VISIBILITIES ARE THE FIRST TO PLUNGE...DOWN TO AROUND A MILE OVER THE WESTERN HALF OR SO OF THE FCST AREA. STILL BELIEVE THE SERN TERMINALS WILL BENEFIT FROM THE BULK OF THE WEATHER LIFTING NORTH OF THE REGION...REMAINING VFR INTO MONDAY. EXPECT RAPID IMPROVEMENT THIS EVENING AS THE AREA OF SNOW DEPARTS. BFD/JST MAY NOT SHARE IN THE IMPROVEMENT...BUT THE REMAINDER OF THE AREA SHOULD SEE VIZ/CIGS IMPROVE WITH THE ENDING OF THE SNOW. A STRONG COLD FRONT WILL PASS EARLY MONDAY...WITH MOST OF THE AREA IMPROVING TO VFR. EXCEPTIONS WILL BE THE MOUNTAINOUS AREAS WHERE SCATTERED SNOW SHOWERS AND LOW CLOUDS WILL KEEP MVFR CONDITIONS IN PLACE INTO MONDAY EVENING...BEFORE DRY ARCTIC AIR BRINGS CLEARING SKIES EVEN THERE. OUTLOOK... MON...MVFR WITH -SHSN WEST...MAINLY VFR CENTRAL AND EASTERN AREAS. TUE...MAINLY VFR. WED-FRI...MAINLY VFR. && .CTP WATCHES/WARNINGS/ADVISORIES... WIND CHILL WATCH FROM MONDAY EVENING THROUGH TUESDAY MORNING FOR PAZ004>006-010>012-017>019-024>026-033>035-037-041-042. && $$ SYNOPSIS...LA CORTE NEAR TERM...FITZGERALD/LA CORTE SHORT TERM...LA CORTE LONG TERM...LAMBERT/GARTNER AVIATION...LA CORTE/MARTIN