Forecast Discussions mentioning any of "HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 11/05/12


AREA FORECAST DISCUSSION
NWS TUCSON AZ
930 AM MST SAT NOV 3 2012 .SYNOPSIS...DRY AND WARMER TO START THE NEW WEEK...WITH NEAR RECORD HIGHS POSSIBLE AROUND TUESDAY. THE PATTERN WILL CHANGE BY THE END OF THE WEEK WITH A PACIFIC STORM SYSTEM BRINGING MUCH COOLER TEMPERATURES...GUSTY WINDS AND A CHANCE OF SHOWERS TO THE REGION. && .DISCUSSION...WEAK TROUGH PHASING INTO NEW MEXICO THIS MORNING. INTERESTING MOISTURE INCREASE NEAR H7 ON THE 12Z KTWC SOUNDING. LARGE PICTURE NOT REALLY MUCH MOISTURE AND DYNAMICS WITH THE IMPULSE...BUT EXPECT SOME CLOUD ENHANCEMENT LATER TODAY AND VIRGA OR EVEN A FEW SPRINKLES NOT OUT OF THE QUESTION IN EASTERN AREAS (HINTED AT BY BOTH 14Z HRRR AND 12Z U OF AZ WRF-NAM). STRONG RIDGE BUILDING IN FROM THE EASTERN PACIFIC OVER THE NEXT 72 HOURS. MIGHT EVEN COME CLOSE TO NEAR RECORD AFTERNOON HIGHS IN A FEW SPOTS TUESDAY OR SO. PATTERN CHANGE FOR THE END OF THE WEEK CONTINUES TO SHAPE UP NICELY. REASONABLE TRENDS ON 00Z ECMWF AND 06Z GFS WITH 12Z GFS NOT QUITE AS DEEP. FOR OUR NECK OF THE WOODS WE COULD SEE SOME LIGHT PRECIP AHEAD OF THE MAIN SYSTEM AS EARLY AS THURSDAY NIGHT WITH THE MAIN TROUGH IMPACT OVER NEXT WEEKEND. A CHANCE OF SHOWERS WITH THE FIRST HIGHER ELEVATION SNOW OF THE SEASON POSSIBLE...BUT STRONG GUSTY WINDS AND MUCH COOLER TEMPERATURES WILL PROBABLY BE THE MAIN STORY. && .AVIATION...KTUS VICINITY EWD FEW-BKN CLOUDS AT 8-12K FT AGL TODAY THEN SKC-SCT CLOUDS ABOVE 20K FT AGL THIS EVENING INTO SUNDAY MORNING. WEST AND NORTHWEST OF KTUS SKC-SCT CLOUDS ABOVE 20K FT AGL THRU 04/15Z. SURFACE WIND GENERALLY LESS THAN 10 KTS THRU EARLY SUNDAY MORNING OR 04/15Z. AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS. && .FIRE WEATHER...DRY CONDITIONS WILL PREVAIL THROUGH THURSDAY. THERE MAY BE A FEW SHOWERS ACROSS THE HIGHER TERRAIN FRIDAY. STRONG WARMING EARLY IN THE NEW WEEK. A COOLING TREND WILL THEN OCCUR LATE NEXT WEEK AS A LOW PRESSURE SYSTEM DEVELOPS OVER THE AREA. MINIMUM DAYTIME RELATIVE HUMIDITIES WILL GENERALLY BE IN THE UPPER SINGLE DIGITS TO THE TEENS. EXPECT NORMAL DIURNAL WIND TRENDS THROUGH MIDWEEK...WITH OCCASIONAL GUSTS DURING THE AFTERNOON HOURS. THEREAFTER...BREEZY TO WINDY CONDITIONS ARE EXPECTED BY FRIDAY AS THE LOW PRESSURE SYSTEM DEEPENS OVER THE AREA. && .TWC WATCHES/WARNINGS/ADVISORIES...NONE. && $$ VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON MEYER/RASMUSSEN
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
636 PM EST SUN NOV 4 2012 .SHORT TERM /TODAY THROUGH TUESDAY/... /ISSUED AT 223 PM EST SUN NOV 4 2012/ LATEST RAP ANALYSIS OVER THE LOCAL AREA SHOWS SURFACE BASED CAPE HAS INCREASED TO BETWEEN 500 J/KG AND 750 J/KG OVER THE SOUTHERN TIER WITH MIXED CAPE VALUES CONSIDERABLY LOWER. BAND OF PRE- FRONTAL -RA CONTINUES TO MAKE STEADY PROGRESS INTO NORTH CENTRAL GEORGIA BUT NO CONVECTIVE ELEMENTS OF NOTE WITH THIS ACTIVITY THUS FAR. INTO THE BETTER INSTABILITY HOWEVER...STARTING TO SEE SOME MORE ORGANIZED ACTIVITY. HOWEVER...FEEL BY THE TIME STRONG OR SEVERE COULD BE REALIZED...BEST LIFT WILL HAVE SHIFTED EAST OUT OF THE AREA THIS EVENING. WILL LIKELY SCALE BACK THE HWO AND ONGOING GRAPHICAST ONCE DEVELOPING LINE SHIFTS EAST. MONDAY LOOKS TO BE THE ONLY SHORT TERM DAY WITH FAIRLY BENIGN CONDITIONS AS HIGH CENTERED OVER CANADA HAS ENOUGH WEAK RIDGING SOUTH INTO THE OUR AREA TO PRODUCE A POP FREE DAY. CLOUDS HOWEVER WILL BECOME PLENTIFUL DURING THE DAY HAS MID AND HIGH LEVEL MOISTURE MAKES A RAPID RETURN TO THE NORTHWEST HALF OF THE REGION. THESE CLOUDS WILL PLAY AN IMPORTANT ROLE AS THEIR ARRIVAL PRIOR TO SUNSET WILL RESULT IN MINS TUESDAY MORNING NOT REACHING THEIR FULL POTENTIAL. THIS WILL BE CRUCIAL AS PRECIP BEGINS TO OVERSPREAD THE AREA IN EARNEST JUST PRIOR TO DAYBREAK TUESDAY AS CLOSED UPPER LOW ROTATES THROUGH THE DEEP SOUTH. NAM12 IS BY FAR THE MOST AGGRESSIVE IN DYNAMICALLY COOLING THE COLUMN...TAKING THE 850MB TEMP FROM +2C TO -1C IN A MATTER OF TWO HOURS. NOT COMPLETELY OUR OF THE QUESTION WITH SUCH A DYNAMIC SYSTEM TO SEE THIS TYPE OF COOLING ALOFT...BUT JUST CANNOT SEEM TO GET SURFACE TEMPS COLD ENOUGH TO ALLOW ANY FROZEN PRECIP TO REACH THE GROUND. THIS IS TRUE EVEN IN THE MOUNTAINS AND WILL KEEP FORECAST ALL LIQUID THIS RUN BUT WILL NEED TO BE MONITORED CLOSELY WITH SUBSEQUENT CYCLES. AS FAR AS THE THUNDER POTENTIAL...BEST SURFACE INSTABILITY SHOULD REMAIN SOUTH OF THE AREA...BUT GIVEN THE AMOUNT OF ISENTROPIC UPGLIDE JUST NORTH OF THE LOW...WILL NEED TO KEEP ISOLATED THUNDER MENTION FOR THE SOUTHERN TIER. DEESE .LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... /ISSUED AT 223 PM EST SUN NOV 4 2012/ GFS AND ECMWF CONTINUE IN ARE IN FAIRLY DECENT AGREEMENT THROUGH THE EXTENDED...AND FOR THE MOST PART AFTER THE SYSTEM EXITS TUESDAY NIGHT THE EXTENDED SHOULD BE DRY WITH A GRADUAL WARMING TREND AS THE MIDLEVEL RIDGE BUILDS IN FROM THE GULF. CORRESPONDING SURFACE HIGH PRESSURE PUSHES THROUGH THE SOUTHEAST THURSDAY INTO FRIDAY...ANCHORING ITSELF IN THE WESTERN ATLANTIC BY SATURDAY BUT WITH STRONG RIDGING REMAINING IN PLACE. HAVE MADE NO SUBSTANTIVE CHANGES TO THE EXTENDED AT THIS TIME. TDP PREV DISCUSSION... /ISSUED 326 AM EST SUN NOV 4 2012/ BIG FORECAST STORY THROUGH THE EXTENDED IS LOW PRESSURE SYSTEM IMPACTING THE AREA TUESDAY THROUGH WEDNESDAY. MODELS CONTINUE TO SUGGEST DEEPENING OF THE LOW OVER THE SOUTHERN ALABAMA AND THE FLORIDA PANHANDLE TUESDAY MORNING THROUGH EARLY AFTERNOON. AS A RESULT OF THE PROJECTED TRACK...EXPECT BEST RAIN CHANGES TO INITIALLY BE ACROSS WESTERN GA LATE ON MONDAY INTO EARLY MORNING TUESDAY...THEN TRANSITIONING TO THE SOUTHERN 2/3 OF THE FORECAST AREA BY TUESDAY MORNING. PREVIOUS MODEL RUNS HAD SUGGESTED MORE ORGANIZED DEVELOPMENT TO OUR SOUTH IN THE FORM OF A SQUALL...CUTTING OFF THE AREA FROM MOISTURE SOURCE...BUT HAVE OPTED TO INCREASE POPS CONSIDERABLY DUE TO THE AGREEMENT WITH THE LATEST MODEL RUNS OF THE NORTHERN MOISTURE PROGRESSION. LITTLE OVERALL INSTABILITY WITH THIS SYSTEM HAS LIMITED THE MENTION OF THUNDER IN THE FORECAST...THOUGH DID KEEP MENTION OF ISOLATED CONVECTION IN THE FAR SE CWA TUESDAY LATE MORNING THROUGH EARLY AFTERNOON. CENTER OF THE SURFACE LOW TRACKS ACROSS NORTHERN FLORIDA INTO TUESDAY NIGHT...AND EMERGES OFF THE GEORGIA AND CAROLINA COASTS BY WEDNESDAY MORNING. HIGH PRESSURE BUILDS IN BEHIND THE LOW AND ASSOCIATED FRONT...KEEPING THE REMAINDER OF THE LONG TERM FORECAST DRY. COOLER TEMPERATURES IN THE MIDDLE OF THE WEEK WILL GRADUALLY WARM BY THE WEEKEND. 31 && AVIATION... 00Z UPDATE... PRECIP HAS DRIED UP AROUND THE TAF SITES AND WILL THEREFORE GO WITH A DRY FORECAST. CIGS ALSO RAISING ACROSS CENTRAL GEORGIA AND WILL REMAIN VFR. SKIES WILL CLEAR FROM THE NORTHWEST WITH ALL SITES HAVING SCT250 BY 03Z. WINDS WILL REMAIN NORTHWEST AND DIMINISH TO 3 TO 5 KTS. WINDS WILL COME AROUND TO THE NORTH AND NORTHEAST AFTER 12Z MONDAY WITH HIGH CLOUDS THROUGH MOST OF THE DAY. EXPECT MID LEVEL CIGS TO MOVE INTO WEST GEORGIA TOWARD 00Z TUE...SPREADING INTO ATL AFTER 00Z WITH SOME 4000 FT CIGS BY 04Z TUE. //ATL CONFIDENCE...00Z UPDATE... MEDIUM ON WIND SHIFT MONDAY. HIGH ON REMAINING ELEMENTS. 17 && .PRELIMINARY POINT TEMPS/POPS... ATHENS 74 44 62 42 / 30 5 0 50 ATLANTA 73 43 64 46 / 30 0 0 60 BLAIRSVILLE 63 37 57 40 / 20 0 0 50 CARTERSVILLE 68 38 63 41 / 20 0 0 60 COLUMBUS 79 44 69 48 / 30 20 0 80 GAINESVILLE 69 45 60 44 / 20 0 0 50 MACON 83 43 68 44 / 30 30 0 80 ROME 67 36 64 40 / 20 0 0 60 PEACHTREE CITY 73 37 65 40 / 40 0 0 70 VIDALIA 86 54 68 49 / 30 40 0 70 && .FFC WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
144 PM EDT SAT NOV 3 2012 .PREV DISCUSSION... /ISSUED 1052 AM EDT SAT NOV 3 2012/ UPDATE... SO SIGNIFICANT CHANGES PLANNED TO THE FORECAST AT THIS TIME. HAVE MADE SOME UPDATES TO ACCOUNT FOR TEMP/DEWPOINT TRENDS...TEMPS RUNNING A LITTLE BELOW FORECAST BUT WITH FULL SUN THEY SHOULD CATCH UP NICELY SO OVERALL NO CHANGES WORTH ISSUING NEW PRODUCTS OVER. NEW HRRR AND THE 00Z FFCWRF KEEP CONVECTION COMPLETELY OUT OF THE AREA UNTIL AFTER 06Z...AND PRETTY ANEMIC AT THAT...SO CURRENT POPS HANDLE THAT WELL AT THIS TIME. WILL REEVALUATE IF NECESSARY WITH THE AFTERNOON PACKAGE. TDP PREV DISCUSSION... /ISSUED 747 AM EDT SAT NOV 3 2012/ PREV DISCUSSION... /ISSUED 425 AM EDT SAT NOV 3 2012/ SHORT TERM /TODAY THROUGH SUNDAY NIGHT/... NORTHWEST FLOW PATTERN AND LONG WAVE TROUGH WILL DOMINATE MUCH OF ERN CONUS THROUGH AT LEAST WED. FIRST OF TWO SHORT WAVES...THE FIRST BEING SIGNIFICANTLY WEAKER...WILL MOVE SE INTO THE MID MS VALLEY SUNDAY WITH WEAK TO MDT WAA ACROSS THE MID SOUTH THROUGH NRN GA AND THE MID ATLANTIC. NOT ENOUGH COMBINED LIFT TO GENERATE MUCH MORE THEN SCT LIGHT SHRA. WITH FAIRLY WARM TEMPS AND WEAK MOISTURE ADVECTION...INSTABILITY WILL BECOME AN ISSUE. 00Z MODELS...ESP 00Z NAM DEVELOPS SOME ELEVATED INSTABILITY TONIGHT...AND EVEN SFC BASED INSTABILITY SUNDAY AFTERNOON...WITH 1000 J/KG AROUND 18-21Z. DUE TO UNCERTAINTY ABOUT MOISTURE RETURN...HIGH MOISTURE BIAS IN NAM AND LACK OF MODEL CONSENSUS...HAVE NOT INCLUDED TSRA IN FCST FOR TONIGHT. DID ADD TSRA FOR SUNDAY AFTERNOON WITH GOOD MODEL CONSENSUS AND FAIRLY WARM TEMPERATURES. DO NOT EXPECT ANY SVR STORMS ATTM AS LARGE SCALE ASCENT....LACK OF STRONG SFC FORCING AND SOMEWHAT WEAK VERTICAL WIND SHEAR FOR THIS TIME OF YEAR WILL NOT BE AT FAVORABLE LEVELS. WEAK FRONT ASSOCIATED WITH WAVE SHOULD PUSH OUT OF CWA BY LATE SUN NIGHT...SO HAVE PUSHED OUT POPS FAIRLY QUICKLY BEHIND FRONT. USED BIAS-CORRECTED MAV/MET BLEND FOR TODAY/TONIGHT AND MAV/MET BLEND WITH HIGHER WEIGHT TOWARD MAV FOR SUN AND SUN NIGHT. SNELSON LONG TERM /MONDAY THROUGH FRIDAY/... EXTENDED MODELS CONTINUE IN GOOD AGREEMENT THROUGH THE WORK WEEK. SHORT WAVE SWINGS OUT OF THE PLAINS MONDAY AFTERNOON INTO THE SOUTHEAST TUESDAY AND INTENSIFIES AS IT LIFTS INTO THE NORTHEAST. FOR THE FORECAST AREA...BOTH MODELS DEVELOP A SURFACE LOW OVER THE NORTHERN GULF OF MEXICO THAT TRACKS OVER SOUTH GEORGIA THROUGH THE DAY. THE TRACK WILL KEEP BEST RAIN CHANCES OVER SOUTH GEORGIA AND BEST INSTABILITY REMAINS OVER FLORIDA. WILL CONTINUE SHOWERS...WITH GOOD CLOUD COVER. NORTHWEST FLOW ALOFT WITH NORTHERLY FLOW AT THE SURFACE WILL BRING ANOTHER COLD SHOT TO THE AREA BY MIDWEEK WITH TEMPERATURES 5 TO 10 DEGREES BELOW NORMALS FOR THIS TIME OF YEAR... BEFORE MODERATING TO NEAR NORMAL BY WEEKS END. ATWELL && .AVIATION... 18Z UPDATE... VFR CONDITIONS WILL CONTINUE THROUGH THE PERIOD EVERYWHERE BUT MCN WHERE MVFR FOG IS EXPECTED FOR A FEW HOURS STARTING AROUND 12Z. SW WINDS TODAY...5-10KT AT ATL AND BELOW 5KT ELSEWHERE...WILL PICK UP ON SUNDAY TO CLOSER TO 10KT AND TURN MORE WESTERLY AHEAD OF A FRONT. ONLY SLIGHT CHANCE SHRA AT MOST SITES THROUGH ABOUT 18Z BUT PROB30 WILL LIKELY BE NEEDED FOR MCN AND CSG THEREAFTER. //ATL CONFIDENCE...18Z UPDATE... HIGH ON ALL ELEMENTS. TDP && .PRELIMINARY POINT TEMPS/POPS... ATHENS 74 53 73 48 / 0 10 20 20 ATLANTA 76 58 72 49 / 0 20 20 20 BLAIRSVILLE 71 50 62 41 / 0 20 30 10 CARTERSVILLE 76 54 68 43 / 0 20 20 10 COLUMBUS 82 59 79 52 / 0 10 30 20 GAINESVILLE 73 55 69 47 / 0 20 20 20 MACON 80 53 80 51 / 0 10 30 20 ROME 77 52 67 41 / 0 20 30 10 PEACHTREE CITY 78 51 73 44 / 0 10 20 20 VIDALIA 78 57 81 55 / 0 10 30 30 && .FFC WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION...UPDATED
NWS PEACHTREE CITY GA
1052 AM EDT SAT NOV 3 2012 .UPDATE... SO SIGNIFICANT CHANGES PLANNED TO THE FORECAST AT THIS TIME. HAVE MADE SOME UPDATES TO ACCOUNT FOR TEMP/DEWPOINT TRENDS...TEMPS RUNNING A LITTLE BELOW FORECAST BUT WITH FULL SUN THEY SHOULD CATCH UP NICELY SO OVERALL NO CHANGES WORTH ISSUING NEW PRODUCTS OVER. NEW HRRR AND THE 00Z FFCWRF KEEP CONVECTION COMPLETELY OUT OF THE AREA UNTIL AFTER 06Z...AND PRETTY ANEMIC AT THAT...SO CURRENT POPS HANDLE THAT WELL AT THIS TIME. WILL REEVALUATE IF NECESSARY WITH THE AFTERNOON PACKAGE. TDP && .PREV DISCUSSION... /ISSUED 747 AM EDT SAT NOV 3 2012/ PREV DISCUSSION... /ISSUED 425 AM EDT SAT NOV 3 2012/ SHORT TERM /TODAY THROUGH SUNDAY NIGHT/... NORTHWEST FLOW PATTERN AND LONG WAVE TROUGH WILL DOMINATE MUCH OF ERN CONUS THROUGH AT LEAST WED. FIRST OF TWO SHORT WAVES...THE FIRST BEING SIGNIFICANTLY WEAKER...WILL MOVE SE INTO THE MID MS VALLEY SUNDAY WITH WEAK TO MDT WAA ACROSS THE MID SOUTH THROUGH NRN GA AND THE MID ATLANTIC. NOT ENOUGH COMBINED LIFT TO GENERATE MUCH MORE THEN SCT LIGHT SHRA. WITH FAIRLY WARM TEMPS AND WEAK MOISTURE ADVECTION...INSTABILITY WILL BECOME AN ISSUE. 00Z MODELS...ESP 00Z NAM DEVELOPS SOME ELEVATED INSTABILITY TONIGHT...AND EVEN SFC BASED INSTABILITY SUNDAY AFTERNOON...WITH 1000 J/KG AROUND 18-21Z. DUE TO UNCERTAINTY ABOUT MOISTURE RETURN...HIGH MOISTURE BIAS IN NAM AND LACK OF MODEL CONSENSUS...HAVE NOT INCLUDED TSRA IN FCST FOR TONIGHT. DID ADD TSRA FOR SUNDAY AFTERNOON WITH GOOD MODEL CONSENSUS AND FAIRLY WARM TEMPERATURES. DO NOT EXPECT ANY SVR STORMS ATTM AS LARGE SCALE ASCENT....LACK OF STRONG SFC FORCING AND SOMEWHAT WEAK VERTICAL WIND SHEAR FOR THIS TIME OF YEAR WILL NOT BE AT FAVORABLE LEVELS. WEAK FRONT ASSOCIATED WITH WAVE SHOULD PUSH OUT OF CWA BY LATE SUN NIGHT...SO HAVE PUSHED OUT POPS FAIRLY QUICKLY BEHIND FRONT. USED BIAS-CORRECTED MAV/MET BLEND FOR TODAY/TONIGHT AND MAV/MET BLEND WITH HIGHER WEIGHT TOWARD MAV FOR SUN AND SUN NIGHT. SNELSON LONG TERM /MONDAY THROUGH FRIDAY/... EXTENDED MODELS CONTINUE IN GOOD AGREEMENT THROUGH THE WORK WEEK. SHORT WAVE SWINGS OUT OF THE PLAINS MONDAY AFTERNOON INTO THE SOUTHEAST TUESDAY AND INTENSIFIES AS IT LIFTS INTO THE NORTHEAST. FOR THE FORECAST AREA...BOTH MODELS DEVELOP A SURFACE LOW OVER THE NORTHERN GULF OF MEXICO THAT TRACKS OVER SOUTH GEORGIA THROUGH THE DAY. THE TRACK WILL KEEP BEST RAIN CHANCES OVER SOUTH GEORGIA AND BEST INSTABILITY REMAINS OVER FLORIDA. WILL CONTINUE SHOWERS...WITH GOOD CLOUD COVER. NORTHWEST FLOW ALOFT WITH NORTHERLY FLOW AT THE SURFACE WILL BRING ANOTHER COLD SHOT TO THE AREA BY MIDWEEK WITH TEMPERATURES 5 TO 10 DEGREES BELOW NORMALS FOR THIS TIME OF YEAR... BEFORE MODERATING TO NEAR NORMAL BY WEEKS END. ATWELL AVIATION... 12Z UPDATE... VFR CONDITIONS WILL PERSIST THRU AT LEAST 12Z SUNDAY. AS A FRONT APPROACHES FROM THE WEST...LIGHT WINDS WILL LIKELY SWITCH TO SE AROUND 14-17Z THIS MORNING BEFORE VEERING TO SW 4-8KTS. CU AROUND 4000FT SHOULD STAY SCT ALL DAY BEFORE DISSIPATING BEFORE SUNSET. CLOUDS WILL INCREASE SUNDAY MORNING AFTER 14Z AS THE COLD FRONT MOVES INTO THE STATE. //ATL CONFIDENCE...12Z UPDATE... MEDIUM CONF ON DURATION OF SE WINDS THIS MORNING. HIGH CONF ON ALL OTHER ELEMENTS. SNELSON && .PRELIMINARY POINT TEMPS/POPS... ATHENS 74 53 73 48 / 5 10 20 20 ATLANTA 76 58 72 49 / 0 20 20 20 BLAIRSVILLE 71 50 62 41 / 10 20 30 10 CARTERSVILLE 76 54 68 43 / 5 20 20 10 COLUMBUS 82 59 79 52 / 0 10 30 20 GAINESVILLE 73 55 69 47 / 5 20 20 20 MACON 80 53 80 51 / 0 10 30 20 ROME 77 52 67 41 / 5 20 30 10 PEACHTREE CITY 78 51 73 44 / 0 10 20 20 VIDALIA 78 57 81 55 / 0 10 30 30 && .FFC WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
249 PM CDT SAT NOV 3 2012 .DISCUSSION... 751 AM CDT MINOR QUICK UPDATES THIS MORNING TO ACCOUNT FOR ONGOING SHOWERS OVER AREAS ALONG AND SOUTH OF A LINE FROM PONTIAC IN ILLINOIS EAST TO FOWLER IN INDIANA. LATEST RADAR IMAGERY DEPICTING A SMALL AREA OF SHOWERS ACROSS THE FAR SOUTHERN TIER OF THE CWA OUT AHEAD OF A MID LEVEL TROUGH AXIS AND AREA OF WAA. INCREASED POPS TO ACCOUNT FOR THESE IN THE NEAR TERM...BUT WITH THESE SHOWERS TO EXIT TO THE EAST/SOUTHEAST OVER THE NEXT SEVERAL HOURS WITH MID LEVEL WINDS VEERING AND BETTER FORCING/WAA EXITING THE CWA. BEST INSTABILITY CURRENTLY RESIDES JUST SOUTH OF THE CWA WHERE RAP ANALYSIS IS SHOWING MUCAPE UP TO 250J/KG...WHERE A FEW LIGHTNING STRIKES HAVE ALSO BEEN REPORTED. PRECIP IN OUR CWA SHOULD REMAIN ONLY SHOWERS BEFORE EXITING...WITH AT MOST A FEW LIGHTNING STRIKES IF THIS WERE TO EVEN OCCUR. RODRIGUEZ //PREV DISCUSSION... 414 AM CDT LARGE SCALE PATTERN TO REMAIN ACTIVE ACROSS THE EASTERN PACIFIC...NORTH AMERICA...AND THE WESTERN ATLANTIC OVER THE NEXT SEVERAL DAYS THOUGH MODELS DO NOT SHOW ANY MAJOR WEATHER SYSTEMS AFFECTING OUR REGION. WHILE SEVERAL DISTURBANCES HAVE MOVED AND WILL CONTINUE TO MOVE ACROSS THE CONTINENT THE OVERALL PATTERN OF AN UPPER TROUGH OVER EASTERN NORTH AMERICA AND A RIDGE OVER THE EASTERN PACIFIC AND WESTERN NORTH AMERICA HAS PERSISTED FOR SEVERAL DAYS AND LOOKS TO REMAIN BASICALLY UNCHANGED UNTIL WE APPROACH MID NEXT WEEK. BY THAT TIME A RATHER SIGNIFICANT CHANGE IN THE OVERALL UPPER PATTERN IS TO HAVE GOTTEN UNDERWAY WITH THE EASTERN NORTH AMERICAN UPPER TROUGH BEING DISPLACED OFF TO THE NORTHEAST OVER THE GULF OF ST. LAWRENCE BY AN UPPER TROUGH TO DEEPEN AS A STRONG JET MAX...THE NOSE OF WHICH WAS CURRENTLY APPROACHING VANCOUVER ISLAND...DIGS SOUTH-SOUTHEAST FROM SASKATCHEWAN AND SOUTHERN MANITOBA OVER THE UPPER AND MS VALLEY...CARVING OUT A SHARP UPPER TROUGH OVER THE OH AND TN VALLEYS AND PROGRESSING EAST TO THE CENTRAL AND SOUTHERN APPALACHIANS BY LATER TUESDAY. UPSTREAM...THIS ALLOWS A STRONG BROAD UPPER RIDGE TO ADVANCE FROM THE WEST COAST TO THE ROCKIES. DURING WEDNESDAY AND THURSDAY THE EASTERN UPPER TROUGH/LOW IS PROGGED TO LIFT NORTHEASTWARD FROM THE MID ATLANTIC COAST TO SOUTHERN NEW ENGLAND...WITH THE UPPER RIDGE MOVING EAST ACROSS THE PLAINS AS A DEEP TROUGH DEVELOPS FROM B.C. SOUTH TO THE NORTHERN CA COAST. TEMPERATURES TO CONTINUE RUNNING A FEW DEGREES BELOW NORMALS THROUGH THE WEEKEND AND INTO EARLY NEXT WEEK THEN MODERATING VERY SLIGHTLY TO NEAR NORMALS FOR MID NEXT WEEK BEFORE MORE SUBSTANTIAL WARMING SPREADS EAST WITH THE UPPER RIDGE AND RAISES TEMPERATURES TO 8...POSSIBLY 10 DEGREES F ABOVE NORMAL BY LATE WEEK. NOTE HOWEVER THAT SOME OF THIS INCREASE AS COMPARED TO NORMALS IS TO TO THE FACT THAT NORMALS TEMPERATURES FALL AT ABOUT 1 DEGREE F EVERY TWO DAYS DUE TO THE INCREASINGLY SHORTER DAYS. SO...BESIDES TEMPERATURES RISING THE NORMALS WILL BE FALLING. LITTLE THREAT OF ANY PRECIPITATION THROUGH NEXT WEEK WITH THE BEST CHANCE...THOUGH STILL ONLY A SMALL ONE...TO BE DURING TUESDAY INTO TUESDAY NIGHT WHEN THERE IS THE POSSIBILITY OF SOME LIGHT RAIN OR RAIN SHOWERS AS A DISTURBANCE DROPS SOUTHEAST ACROSS THE UPPER MIDWEST INTO THE NORTHERN GREAT LAKES. OTHERWISE...ONLY A SLIGHT CHANCE OF SOME LAKE EFFECT SPRINKLES/VERY LIGHT RAIN SHOWERS NEAR LAKE MI TONIGHT. IN THE SHORT...TERM WEAK RADAR ECHOES WERE OBSERVED MOVING FROM NORTHWEST IL SOUTHEASTWARD DURING THE LATE EVENING AND EARLY DURING THE OVERNIGHT BUT THEY HAVE DISSIPATED OVER THE LAST COUPLE HOURS. MEANWHILE...AS ANTICIPATED LAST NIGHT...FORCING HAD SHIFTED SOUTH TO NORTHEAST MO AND CENTRAL IL AHEAD OF A SHORT WAVE MOVING EAST FROM EASTERN KS AND NE TO IA AND MO. THIS FORCING IS ALONG A STRONG BAROCLINIC ZONE /PER 03.00Z RAOBS 850 HPA TEMPERATURES OF +12C AND +17C AT TOP AND SGF RESPECTIVELY... WITH MPX AT 0C AND GRB -6C/ THAT EXTENDS NW-SE ACROSS IA AND IL TO THE LOWER OH VALLEY. THIS FORCING HAS RESULTED IN ELEVATED CONVECTION BREAKING OUT ACROSS CENTRAL IL SOUTH OF U.S. 136. THE SHORT WAVE IS PROGGED TO CONTINUE EASTWARD ACROSS THE MID MS VALLEY TODAY THOUGH WEAKEN AS IT DOES. WITH THE MAIN FORCING REMAINING ACROSS CENTRAL IL ONLY THE EXTREME SOUTHERN FRINGE OF THE LOCAL FORECAST AREA WILL HAVE A SLIGHT CHANCE OF A A FEW SHOWERS THIS MORNING. LOW LEVEL FLOW OVER SOUTHERN LAKE MI HAS BECOME RATER LIGHT EAST- NORTHEAST. WHILE LAKE EFFECT CLOUDS CONTINUE TO BE GENERATED BY THE COOL AIR FLOWING OVER THE RELATIVELY WARM WATER THE SHORT FETCH AND SUPPRESSED EQUILIBRIUM LEVEL WILL PREVENT ANY LAKE EFFECT SHOWERS TODAY. TONIGHT...LOW LEVEL FLOW RETURNS TO NORTH AND NORTH-NORTHEAST. THE INCREASED FETCH DOWN THE LAKE WILL ENCOURAGE ADDITIONAL LAKE EFFECT CLOUDS AND POSSIBLY SOME SHOWERS THOUGH CLOUD DEPTHS BASED ON FORECAST TEMPERATURE PROFILES OVER THE WATER TONIGHT SUGGEST THEY WOULD BE ONLY SOME SPRINKLES NEAR THE LAKE OR AT THE MOST A FEW SMALL LIGHT RAIN SHOWERS. DURING SUNDAY AND SUNDAY NIGHT A SHORT WAVE EJECTED FROM THE UPPER LOW IN THE GULF OF AK IS PROGGED TO DROP SOUTH-SOUTHEAST FROM SOUTHERN SASKATCHEWAN ACROSS THE DAKOTAS AND TO THE MID MO VALLEY. MODELS THEN TURN IT TO THE SOUTHEAST AND EAST-SOUTHEAST MONDAY AND TO THE TN VALLEY MONDAY NIGHT. THIS TRACK IS WELL REMOVED FROM THE LOCAL AREA AND ANY ASSOCIATED RAIN WILL STAY TO THE WEST THROUGH SOUTH OF THE FORECAST AREA. THE ONE CHANCE OF RAIN DURING THE NEXT SEVEN DAYS COMES ON TUESDAY INTO TUESDAY NIGHT AS A SHORT WAVE DROPS FROM MANITOBA AND WESTERN ONTARIO TO THE UPPER GREAT LAKES. BEST FORCING WITH THIS DISTURBANCE WILL BE ACROSS THE NORTH WOODS AND THE NORTHERN GREAT LAKES...WITH ONLY A SLIGHT CHANCE OF MEASURABLE RAIN AS FAR SOUTH AS NORTH CENTRAL AND NORTHEAST IL WITH JUST A SLIGHT CHANCE FURTHER S TOWARDS CENTRAL IL. TRS && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 20Z... * MVFR CIGS 2500-3000 FT...POSSIBLY SCATTERING FOR A TIME LATE THIS AFTERNOON/EVENING. A FEW SPRINKLES POSSIBLE THROUGH 2130-22Z. * LAKE-INDUCED MVFR STRATOCU LIKELY REDEVELOPING TONIGHT... ESPECIALLY AT KMDW. RATZER //DISCUSSION...UPDATED 18Z... AREA OF LOW PRESSURE WAS OVER THE MISSOURI BOOT HEEL AT MIDDAY... ASSOCIATED WITH MID-LEVEL DISTURBANCE PASSING ACROSS THE REGION. ANOTHER MID-LEVEL SYSTEM WAS MOVING ACROSS WI...MAINTAINING BROKEN MID-LEVEL DECK ACROSS THE AREA. IN THE LOW LEVELS...WINDS HAD SHIFTED MORE EASTERLY TO THE NORTH OF THE LOW PRESSURE SYSTEM PASSING SOUTH OF THE TERMINALS...BUT ARE EXPECTED TO BACK MORE NORTH-NORTHEAST THIS AFTERNOON AND EVENING AS THE LOW TRACKS INTO THE OHIO VALLEY. BENEATH THE MID-CLOUDS...MVFR STRATOCU IN THE 2500-3000 FT RANGE HAS PUSHED INLAND OFF OF THE LAKE...THOUGH GUIDANCE REMAINS CONSISTENT IN DEPICTING LOW CLOUDS ERODING DURING THE MID/LATE AFTERNOON HOURS AS WIND FIELD WEAKENS. FORECAST SOUNDINGS INDICATE THE NORTH-NORTHEAST FLOW OVER THE LAKE WILL STRENGTHEN AGAIN THIS EVENING...INCREASING CONVERGENCE OVER THE WESTERN PARTS OF THE LAKE AND REINFORCING A WEST-SOUTHWESTWARD PUSH OF MVFR STRATOCU. GYY AND MDW WOULD APPEAR MOST LIKELY TO SEE MORE PERSISTENT CEILINGS IN THE 2500-3000 FT RANGE...WITH ORD/DPA ON THE WESTERN FRINGE. EXPECT BASES TO RISE ABOVE 3000 FT BEYOND SUNRISE SUNDAY MORNING. COULD SEE SOME SPRINKLES FROM THESE LAKE- INDUCED CLOUDS...THOUGH TIMING/LOCATION TOO UNCERTAIN TO INCLUDE IN POINT FORECASTS ATTM. WINDS...10 KTS OR LESS SHOULD BACK FROM EAST-NORTHEAST TO NORTH- NORTHEAST THIS AFTERNOON...AND WILL LIKELY FLOP TO 340-350 LATE THIS EVENING AT ORD/DPA BEFORE BECOMING NORTHEAST AGAIN SUNDAY MORNING. RATZER //ORD AND MDW CONFIDENCE...UPDATED 20Z... * MEDIUM CONFIDENCE IN CEILING TRENDS THIS AFTERNOON/TONIGHT. * HIGH CONFIDENCE IN WIND TRENDS. RATZER //OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z... SUNDAY NIGHT-MONDAY...VFR. TUESDAY...CHC OF -RA. MVFR POSSIBLE. WEDNESDAY-FRIDAY...VFR. MTF && .MARINE... 212 AM CDT NORTHERLY WINDS CONTINUE OVER THE LAKE...NOW GOING ON ALMOST A WEEK STRAIGHT FROM THAT DIRECTION. THE RIDGE AXIS FROM WESTERN QUEBEC TO NORTHERN IL WILL PUSH OVER THE LAKE BY LATER SUNDAY AND PERSIST INTO THE DAY MONDAY...BRINGING LIGHT WINDS. BEFORE THAT TIME...THE NORTHERLY WINDS AND WAVES WILL SLOWLY DIMINISH TODAY. WAVES OF 4 TO 5 FT WILL REMAIN POSSIBLE IN THE NEARSHORE AREAS OF IL AND IN EVEN AFTER THE SMALL CRAFT ADVISORY EXPIRATION...BUT THAT SHOULD BE ON THE UPPER END OF WAVE HEIGHTS...SO NO EXTENSION IN THE HEADLINE PLANNED AT THIS TIME. AFTER THE RIDGE AXIS PASSES...SOUTHERLY WINDS WILL RETURN OVER THE LAKE AND INCREASE ON TUESDAY AS A LOW PROGRESSES EAST ACROSS THE CANADIAN PRAIRIE PROVINCES. A COLD FRONT EXTENDING SOUTH FROM THIS WILL MOVE EAST OVER THE LAKE SOMETIME TUESDAY NIGHT OR WEDNESDAY. THIS IS NOT EXPECTED TO BE TOO POWERFUL OF A FRONT AS A STRONG LOW OFF THE EAST COAST SHOULD CAUSE THIS NORTHERN STREAM SYSTEM TO SLOW AND LIKELY WEAKEN. MTF && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...NONE. && $$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1243 PM CDT SAT NOV 3 2012 .DISCUSSION... 751 AM CDT MINOR QUICK UPDATES THIS MORNING TO ACCOUNT FOR ONGOING SHOWERS OVER AREAS ALONG AND SOUTH OF A LINE FROM PONTIAC IN ILLINOIS EAST TO FOWLER IN INDIANA. LATEST RADAR IMAGERY DEPICTING A SMALL AREA OF SHOWERS ACROSS THE FAR SOUTHERN TIER OF THE CWA OUT AHEAD OF A MID LEVEL TROUGH AXIS AND AREA OF WAA. INCREASED POPS TO ACCOUNT FOR THESE IN THE NEAR TERM...BUT WITH THESE SHOWERS TO EXIT TO THE EAST/SOUTHEAST OVER THE NEXT SEVERAL HOURS WITH MID LEVEL WINDS VEERING AND BETTER FORCING/WAA EXITING THE CWA. BEST INSTABILITY CURRENTLY RESIDES JUST SOUTH OF THE CWA WHERE RAP ANALYSIS IS SHOWING MUCAPE UP TO 250J/KG...WHERE A FEW LIGHTNING STRIKES HAVE ALSO BEEN REPORTED. PRECIP IN OUR CWA SHOULD REMAIN ONLY SHOWERS BEFORE EXITING...WITH AT MOST A FEW LIGHTNING STRIKES IF THIS WERE TO EVEN OCCUR. RODRIGUEZ //PREV DISCUSSION... 414 AM CDT LARGE SCALE PATTERN TO REMAIN ACTIVE ACROSS THE EASTERN PACIFIC...NORTH AMERICA...AND THE WESTERN ATLANTIC OVER THE NEXT SEVERAL DAYS THOUGH MODELS DO NOT SHOW ANY MAJOR WEATHER SYSTEMS AFFECTING OUR REGION. WHILE SEVERAL DISTURBANCES HAVE MOVED AND WILL CONTINUE TO MOVE ACROSS THE CONTINENT THE OVERALL PATTERN OF AN UPPER TROUGH OVER EASTERN NORTH AMERICA AND A RIDGE OVER THE EASTERN PACIFIC AND WESTERN NORTH AMERICA HAS PERSISTED FOR SEVERAL DAYS AND LOOKS TO REMAIN BASICALLY UNCHANGED UNTIL WE APPROACH MID NEXT WEEK. BY THAT TIME A RATHER SIGNIFICANT CHANGE IN THE OVERALL UPPER PATTERN IS TO HAVE GOTTEN UNDERWAY WITH THE EASTERN NORTH AMERICAN UPPER TROUGH BEING DISPLACED OFF TO THE NORTHEAST OVER THE GULF OF ST. LAWRENCE BY AN UPPER TROUGH TO DEEPEN AS A STRONG JET MAX...THE NOSE OF WHICH WAS CURRENTLY APPROACHING VANCOUVER ISLAND...DIGS SOUTH-SOUTHEAST FROM SASKATCHEWAN AND SOUTHERN MANITOBA OVER THE UPPER AND MS VALLEY...CARVING OUT A SHARP UPPER TROUGH OVER THE OH AND TN VALLEYS AND PROGRESSING EAST TO THE CENTRAL AND SOUTHERN APPALACHIANS BY LATER TUESDAY. UPSTREAM...THIS ALLOWS A STRONG BROAD UPPER RIDGE TO ADVANCE FROM THE WEST COAST TO THE ROCKIES. DURING WEDNESDAY AND THURSDAY THE EASTERN UPPER TROUGH/LOW IS PROGGED TO LIFT NORTHEASTWARD FROM THE MID ATLANTIC COAST TO SOUTHERN NEW ENGLAND...WITH THE UPPER RIDGE MOVING EAST ACROSS THE PLAINS AS A DEEP TROUGH DEVELOPS FROM B.C. SOUTH TO THE NORTHERN CA COAST. TEMPERATURES TO CONTINUE RUNNING A FEW DEGREES BELOW NORMALS THROUGH THE WEEKEND AND INTO EARLY NEXT WEEK THEN MODERATING VERY SLIGHTLY TO NEAR NORMALS FOR MID NEXT WEEK BEFORE MORE SUBSTANTIAL WARMING SPREADS EAST WITH THE UPPER RIDGE AND RAISES TEMPERATURES TO 8...POSSIBLY 10 DEGREES F ABOVE NORMAL BY LATE WEEK. NOTE HOWEVER THAT SOME OF THIS INCREASE AS COMPARED TO NORMALS IS TO TO THE FACT THAT NORMALS TEMPERATURES FALL AT ABOUT 1 DEGREE F EVERY TWO DAYS DUE TO THE INCREASINGLY SHORTER DAYS. SO...BESIDES TEMPERATURES RISING THE NORMALS WILL BE FALLING. LITTLE THREAT OF ANY PRECIPITATION THROUGH NEXT WEEK WITH THE BEST CHANCE...THOUGH STILL ONLY A SMALL ONE...TO BE DURING TUESDAY INTO TUESDAY NIGHT WHEN THERE IS THE POSSIBILITY OF SOME LIGHT RAIN OR RAIN SHOWERS AS A DISTURBANCE DROPS SOUTHEAST ACROSS THE UPPER MIDWEST INTO THE NORTHERN GREAT LAKES. OTHERWISE...ONLY A SLIGHT CHANCE OF SOME LAKE EFFECT SPRINKLES/VERY LIGHT RAIN SHOWERS NEAR LAKE MI TONIGHT. IN THE SHORT...TERM WEAK RADAR ECHOES WERE OBSERVED MOVING FROM NORTHWEST IL SOUTHEASTWARD DURING THE LATE EVENING AND EARLY DURING THE OVERNIGHT BUT THEY HAVE DISSIPATED OVER THE LAST COUPLE HOURS. MEANWHILE...AS ANTICIPATED LAST NIGHT...FORCING HAD SHIFTED SOUTH TO NORTHEAST MO AND CENTRAL IL AHEAD OF A SHORT WAVE MOVING EAST FROM EASTERN KS AND NE TO IA AND MO. THIS FORCING IS ALONG A STRONG BAROCLINIC ZONE /PER 03.00Z RAOBS 850 HPA TEMPERATURES OF +12C AND +17C AT TOP AND SGF RESPECTIVELY... WITH MPX AT 0C AND GRB -6C/ THAT EXTENDS NW-SE ACROSS IA AND IL TO THE LOWER OH VALLEY. THIS FORCING HAS RESULTED IN ELEVATED CONVECTION BREAKING OUT ACROSS CENTRAL IL SOUTH OF U.S. 136. THE SHORT WAVE IS PROGGED TO CONTINUE EASTWARD ACROSS THE MID MS VALLEY TODAY THOUGH WEAKEN AS IT DOES. WITH THE MAIN FORCING REMAINING ACROSS CENTRAL IL ONLY THE EXTREME SOUTHERN FRINGE OF THE LOCAL FORECAST AREA WILL HAVE A SLIGHT CHANCE OF A A FEW SHOWERS THIS MORNING. LOW LEVEL FLOW OVER SOUTHERN LAKE MI HAS BECOME RATER LIGHT EAST- NORTHEAST. WHILE LAKE EFFECT CLOUDS CONTINUE TO BE GENERATED BY THE COOL AIR FLOWING OVER THE RELATIVELY WARM WATER THE SHORT FETCH AND SUPPRESSED EQUILIBRIUM LEVEL WILL PREVENT ANY LAKE EFFECT SHOWERS TODAY. TONIGHT...LOW LEVEL FLOW RETURNS TO NORTH AND NORTH-NORTHEAST. THE INCREASED FETCH DOWN THE LAKE WILL ENCOURAGE ADDITIONAL LAKE EFFECT CLOUDS AND POSSIBLY SOME SHOWERS THOUGH CLOUD DEPTHS BASED ON FORECAST TEMPERATURE PROFILES OVER THE WATER TONIGHT SUGGEST THEY WOULD BE ONLY SOME SPRINKLES NEAR THE LAKE OR AT THE MOST A FEW SMALL LIGHT RAIN SHOWERS. DURING SUNDAY AND SUNDAY NIGHT A SHORT WAVE EJECTED FROM THE UPPER LOW IN THE GULF OF AK IS PROGGED TO DROP SOUTH-SOUTHEAST FROM SOUTHERN SASKATCHEWAN ACROSS THE DAKOTAS AND TO THE MID MO VALLEY. MODELS THEN TURN IT TO THE SOUTHEAST AND EAST-SOUTHEAST MONDAY AND TO THE TN VALLEY MONDAY NIGHT. THIS TRACK IS WELL REMOVED FROM THE LOCAL AREA AND ANY ASSOCIATED RAIN WILL STAY TO THE WEST THROUGH SOUTH OF THE FORECAST AREA. THE ONE CHANCE OF RAIN DURING THE NEXT SEVEN DAYS COMES ON TUESDAY INTO TUESDAY NIGHT AS A SHORT WAVE DROPS FROM MANITOBA AND WESTERN ONTARIO TO THE UPPER GREAT LAKES. BEST FORCING WITH THIS DISTURBANCE WILL BE ACROSS THE NORTH WOODS AND THE NORTHERN GREAT LAKES...WITH ONLY A SLIGHT CHANCE OF MEASURABLE RAIN AS FAR SOUTH AS NORTH CENTRAL AND NORTHEAST IL WITH JUST A SLIGHT CHANCE FURTHER S TOWARDS CENTRAL IL. TRS && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 18Z... * MVFR CIGS AROUND 3000 FT...POSSIBLY SCATTERING FOR A TIME LATE THIS AFTERNOON/EVENING. * LAKE-INDUCED MVFR STRATOCU LIKELY REDEVELOPING TONIGHT... ESPECIALLY AT KMDW. RATZER //DISCUSSION...UPDATED 18Z... AREA OF LOW PRESSURE WAS OVER THE MISSOURI BOOT HEEL AT MIDDAY... ASSOCIATED WITH MID-LEVEL DISTURBANCE PASSING ACROSS THE REGION. ANOTHER MID-LEVEL SYSTEM WAS MOVING ACROSS WI...MAINTAINING BROKEN MID-LEVEL DECK ACROSS THE AREA. IN THE LOW LEVELS...WINDS HAD SHIFTED MORE EASTERLY TO THE NORTH OF THE LOW PRESSURE SYSTEM PASSING SOUTH OF THE TERMINALS...BUT ARE EXPECTED TO BACK MORE NORTH-NORTHEAST THIS AFTERNOON AND EVENING AS THE LOW TRACKS INTO THE OHIO VALLEY. BENEATH THE MID-CLOUDS...MVFR STRATOCU IN THE 2500-3000 FT RANGE HAS PUSHED INLAND OFF OF THE LAKE...THOUGH GUIDANCE REMAINS CONSISTENT IN DEPICTING LOW CLOUDS ERODING DURING THE MID/LATE AFTERNOON HOURS AS WIND FIELD WEAKENS. FORECAST SOUNDINGS INDICATE THE NORTH-NORTHEAST FLOW OVER THE LAKE WILL STRENGTHEN AGAIN THIS EVENING...INCREASING CONVERGENCE OVER THE WESTERN PARTS OF THE LAKE AND REINFORCING A WEST-SOUTHWESTWARD PUSH OF MVFR STRATOCU. GYY AND MDW WOULD APPEAR MOST LIKELY TO SEE MORE PERSISTENT CEILINGS IN THE 2500-3000 FT RANGE...WITH ORD/DPA ON THE WESTERN FRINGE. EXPECT BASES TO RISE ABOVE 3000 FT BEYOND SUNRISE SUNDAY MORNING. COULD SEE SOME SPRINKLES FROM THESE LAKE- INDUCED CLOUDS...THOUGH TIMING/LOCATION TOO UNCERTAIN TO INCLUDE IN POINT FORECASTS ATTM. WINDS...10 KTS OR LESS SHOULD BACK FROM EAST-NORTHEAST TO NORTH- NORTHEAST THIS AFTERNOON...AND WILL LIKELY FLOP TO 340-350 LATE THIS EVENING AT ORD/DPA BEFORE BECOMING NORTHEAST AGAIN SUNDAY MORNING. RATZER //ORD AND MDW CONFIDENCE...UPDATED 18Z... * MEDIUM CONFIDENCE IN CEILING TRENDS THIS AFTERNOON/TONIGHT. * HIGH CONFIDENCE IN WIND TRENDS. RATZER //OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z... SUNDAY NIGHT-MONDAY...VFR. TUESDAY...CHC OF -RA. MVFR POSSIBLE. WEDNESDAY-FRIDAY...VFR. MTF && .MARINE... 212 AM CDT NORTHERLY WINDS CONTINUE OVER THE LAKE...NOW GOING ON ALMOST A WEEK STRAIGHT FROM THAT DIRECTION. THE RIDGE AXIS FROM WESTERN QUEBEC TO NORTHERN IL WILL PUSH OVER THE LAKE BY LATER SUNDAY AND PERSIST INTO THE DAY MONDAY...BRINGING LIGHT WINDS. BEFORE THAT TIME...THE NORTHERLY WINDS AND WAVES WILL SLOWLY DIMINISH TODAY. WAVES OF 4 TO 5 FT WILL REMAIN POSSIBLE IN THE NEARSHORE AREAS OF IL AND IN EVEN AFTER THE SMALL CRAFT ADVISORY EXPIRATION...BUT THAT SHOULD BE ON THE UPPER END OF WAVE HEIGHTS...SO NO EXTENSION IN THE HEADLINE PLANNED AT THIS TIME. AFTER THE RIDGE AXIS PASSES...SOUTHERLY WINDS WILL RETURN OVER THE LAKE AND INCREASE ON TUESDAY AS A LOW PROGRESSES EAST ACROSS THE CANADIAN PRAIRIE PROVINCES. A COLD FRONT EXTENDING SOUTH FROM THIS WILL MOVE EAST OVER THE LAKE SOMETIME TUESDAY NIGHT OR WEDNESDAY. THIS IS NOT EXPECTED TO BE TOO POWERFUL OF A FRONT AS A STRONG LOW OFF THE EAST COAST SHOULD CAUSE THIS NORTHERN STREAM SYSTEM TO SLOW AND LIKELY WEAKEN. MTF && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...NONE. && $$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1104 AM CDT SAT NOV 3 2012 .DISCUSSION... 751 AM CDT MINOR QUICK UPDATES THIS MORNING TO ACCOUNT FOR ONGOING SHOWERS OVER AREAS ALONG AND SOUTH OF A LINE FROM PONTIAC IN ILLINOIS EAST TO FOWLER IN INDIANA. LATEST RADAR IMAGERY DEPICTING A SMALL AREA OF SHOWERS ACROSS THE FAR SOUTHERN TIER OF THE CWA OUT AHEAD OF A MID LEVEL TROUGH AXIS AND AREA OF WAA. INCREASED POPS TO ACCOUNT FOR THESE IN THE NEAR TERM...BUT WITH THESE SHOWERS TO EXIT TO THE EAST/SOUTHEAST OVER THE NEXT SEVERAL HOURS WITH MID LEVEL WINDS VEERING AND BETTER FORCING/WAA EXITING THE CWA. BEST INSTABILITY CURRENTLY RESIDES JUST SOUTH OF THE CWA WHERE RAP ANALYSIS IS SHOWING MUCAPE UP TO 250J/KG...WHERE A FEW LIGHTNING STRIKES HAVE ALSO BEEN REPORTED. PRECIP IN OUR CWA SHOULD REMAIN ONLY SHOWERS BEFORE EXITING...WITH AT MOST A FEW LIGHTNING STRIKES IF THIS WERE TO EVEN OCCUR. RODRIGUEZ //PREV DISCUSSION... 414 AM CDT LARGE SCALE PATTERN TO REMAIN ACTIVE ACROSS THE EASTERN PACIFIC...NORTH AMERICA...AND THE WESTERN ATLANTIC OVER THE NEXT SEVERAL DAYS THOUGH MODELS DO NOT SHOW ANY MAJOR WEATHER SYSTEMS AFFECTING OUR REGION. WHILE SEVERAL DISTURBANCES HAVE MOVED AND WILL CONTINUE TO MOVE ACROSS THE CONTINENT THE OVERALL PATTERN OF AN UPPER TROUGH OVER EASTERN NORTH AMERICA AND A RIDGE OVER THE EASTERN PACIFIC AND WESTERN NORTH AMERICA HAS PERSISTED FOR SEVERAL DAYS AND LOOKS TO REMAIN BASICALLY UNCHANGED UNTIL WE APPROACH MID NEXT WEEK. BY THAT TIME A RATHER SIGNIFICANT CHANGE IN THE OVERALL UPPER PATTERN IS TO HAVE GOTTEN UNDERWAY WITH THE EASTERN NORTH AMERICAN UPPER TROUGH BEING DISPLACED OFF TO THE NORTHEAST OVER THE GULF OF ST. LAWRENCE BY AN UPPER TROUGH TO DEEPEN AS A STRONG JET MAX...THE NOSE OF WHICH WAS CURRENTLY APPROACHING VANCOUVER ISLAND...DIGS SOUTH-SOUTHEAST FROM SASKATCHEWAN AND SOUTHERN MANITOBA OVER THE UPPER AND MS VALLEY...CARVING OUT A SHARP UPPER TROUGH OVER THE OH AND TN VALLEYS AND PROGRESSING EAST TO THE CENTRAL AND SOUTHERN APPALACHIANS BY LATER TUESDAY. UPSTREAM...THIS ALLOWS A STRONG BROAD UPPER RIDGE TO ADVANCE FROM THE WEST COAST TO THE ROCKIES. DURING WEDNESDAY AND THURSDAY THE EASTERN UPPER TROUGH/LOW IS PROGGED TO LIFT NORTHEASTWARD FROM THE MID ATLANTIC COAST TO SOUTHERN NEW ENGLAND...WITH THE UPPER RIDGE MOVING EAST ACROSS THE PLAINS AS A DEEP TROUGH DEVELOPS FROM B.C. SOUTH TO THE NORTHERN CA COAST. TEMPERATURES TO CONTINUE RUNNING A FEW DEGREES BELOW NORMALS THROUGH THE WEEKEND AND INTO EARLY NEXT WEEK THEN MODERATING VERY SLIGHTLY TO NEAR NORMALS FOR MID NEXT WEEK BEFORE MORE SUBSTANTIAL WARMING SPREADS EAST WITH THE UPPER RIDGE AND RAISES TEMPERATURES TO 8...POSSIBLY 10 DEGREES F ABOVE NORMAL BY LATE WEEK. NOTE HOWEVER THAT SOME OF THIS INCREASE AS COMPARED TO NORMALS IS TO TO THE FACT THAT NORMALS TEMPERATURES FALL AT ABOUT 1 DEGREE F EVERY TWO DAYS DUE TO THE INCREASINGLY SHORTER DAYS. SO...BESIDES TEMPERATURES RISING THE NORMALS WILL BE FALLING. LITTLE THREAT OF ANY PRECIPITATION THROUGH NEXT WEEK WITH THE BEST CHANCE...THOUGH STILL ONLY A SMALL ONE...TO BE DURING TUESDAY INTO TUESDAY NIGHT WHEN THERE IS THE POSSIBILITY OF SOME LIGHT RAIN OR RAIN SHOWERS AS A DISTURBANCE DROPS SOUTHEAST ACROSS THE UPPER MIDWEST INTO THE NORTHERN GREAT LAKES. OTHERWISE...ONLY A SLIGHT CHANCE OF SOME LAKE EFFECT SPRINKLES/VERY LIGHT RAIN SHOWERS NEAR LAKE MI TONIGHT. IN THE SHORT...TERM WEAK RADAR ECHOES WERE OBSERVED MOVING FROM NORTHWEST IL SOUTHEASTWARD DURING THE LATE EVENING AND EARLY DURING THE OVERNIGHT BUT THEY HAVE DISSIPATED OVER THE LAST COUPLE HOURS. MEANWHILE...AS ANTICIPATED LAST NIGHT...FORCING HAD SHIFTED SOUTH TO NORTHEAST MO AND CENTRAL IL AHEAD OF A SHORT WAVE MOVING EAST FROM EASTERN KS AND NE TO IA AND MO. THIS FORCING IS ALONG A STRONG BAROCLINIC ZONE /PER 03.00Z RAOBS 850 HPA TEMPERATURES OF +12C AND +17C AT TOP AND SGF RESPECTIVELY... WITH MPX AT 0C AND GRB -6C/ THAT EXTENDS NW-SE ACROSS IA AND IL TO THE LOWER OH VALLEY. THIS FORCING HAS RESULTED IN ELEVATED CONVECTION BREAKING OUT ACROSS CENTRAL IL SOUTH OF U.S. 136. THE SHORT WAVE IS PROGGED TO CONTINUE EASTWARD ACROSS THE MID MS VALLEY TODAY THOUGH WEAKEN AS IT DOES. WITH THE MAIN FORCING REMAINING ACROSS CENTRAL IL ONLY THE EXTREME SOUTHERN FRINGE OF THE LOCAL FORECAST AREA WILL HAVE A SLIGHT CHANCE OF A A FEW SHOWERS THIS MORNING. LOW LEVEL FLOW OVER SOUTHERN LAKE MI HAS BECOME RATER LIGHT EAST- NORTHEAST. WHILE LAKE EFFECT CLOUDS CONTINUE TO BE GENERATED BY THE COOL AIR FLOWING OVER THE RELATIVELY WARM WATER THE SHORT FETCH AND SUPPRESSED EQUILIBRIUM LEVEL WILL PREVENT ANY LAKE EFFECT SHOWERS TODAY. TONIGHT...LOW LEVEL FLOW RETURNS TO NORTH AND NORTH-NORTHEAST. THE INCREASED FETCH DOWN THE LAKE WILL ENCOURAGE ADDITIONAL LAKE EFFECT CLOUDS AND POSSIBLY SOME SHOWERS THOUGH CLOUD DEPTHS BASED ON FORECAST TEMPERATURE PROFILES OVER THE WATER TONIGHT SUGGEST THEY WOULD BE ONLY SOME SPRINKLES NEAR THE LAKE OR AT THE MOST A FEW SMALL LIGHT RAIN SHOWERS. DURING SUNDAY AND SUNDAY NIGHT A SHORT WAVE EJECTED FROM THE UPPER LOW IN THE GULF OF AK IS PROGGED TO DROP SOUTH-SOUTHEAST FROM SOUTHERN SASKATCHEWAN ACROSS THE DAKOTAS AND TO THE MID MO VALLEY. MODELS THEN TURN IT TO THE SOUTHEAST AND EAST-SOUTHEAST MONDAY AND TO THE TN VALLEY MONDAY NIGHT. THIS TRACK IS WELL REMOVED FROM THE LOCAL AREA AND ANY ASSOCIATED RAIN WILL STAY TO THE WEST THROUGH SOUTH OF THE FORECAST AREA. THE ONE CHANCE OF RAIN DURING THE NEXT SEVEN DAYS COMES ON TUESDAY INTO TUESDAY NIGHT AS A SHORT WAVE DROPS FROM MANITOBA AND WESTERN ONTARIO TO THE UPPER GREAT LAKES. BEST FORCING WITH THIS DISTURBANCE WILL BE ACROSS THE NORTH WOODS AND THE NORTHERN GREAT LAKES...WITH ONLY A SLIGHT CHANCE OF MEASURABLE RAIN AS FAR SOUTH AS NORTH CENTRAL AND NORTHEAST IL WITH JUST A SLIGHT CHANCE FURTHER S TOWARDS CENTRAL IL. TRS && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 16Z... * MVFR CIGS 2500-3000 FT LINGERING THROUGH EARLY AFTERNOON. * LOW PROBABILITY POTENTIAL FOR A FEW SPRINKLES FOR SAME TIME RANGE. RATZER //DISCUSSION...UPDATED 16Z... 12Z GUIDANCE MAINTAINS TREND OF HOLDING 2500-3000 FT CIGS ACROSS CHI AREA TERMINALS THROUGH EARLY AFTERNOON...WITH INDICATION OF SCATTERING OF LOWER CLOUDS MID/LATE AFTERNOON. WEAK RADAR RETURNS DRIFTING WEST-SOUTHWEST OFF LAKE MICHIGAN INDICATE POTENTIAL FOR A FEW SPRINKLES...THOUGH REFLECTIVITY HAS WEAKENED OVER PAST 2 HOURS AND FORECAST WIND PROFILES APPEAR TO WEAKEN FOR A TIME THIS AFTERNOON LOWERING PROBABILITY OF ORGANIZED PRECIP. RATZER PREVIOUS DISCUSSION FROM 12Z... HIGH PRESSURE REMAINS ANCHORED FROM WESTERN ONTARIO SOUTHWARD INTO EASTERN WI. THE FLOW AROUND THIS FEATURE CONTINUES AND WILL THROUGH TODAY...MEANING NORTHEAST WINDS ACROSS THE AREA. THERE MAY BE A LITTLE LAKE EMPHASIS THIS AFTERNOON THAT COULD LEAD TO A FEW KNOT INCREASE...BUT ALL IN ALL A FAIRLY PERSISTENT NORTHEAST WIND WILL PREVAIL. THE FLOW OFF THE WARM LAKE CONTINUES TO OFFER STRATOCUMULUS CLOUDS. THESE SHOULD REMAIN BROKEN OVER ORD AND DPA FOR MUCH IF NOT THE ENTIRE MORNING WITH A GRADUAL LIFTING AND POTENTIALLY SOME SCATTERING EXPECTED THIS AFTERNOON. AS FOR THE SOUTHERN CHICAGOLAND SITES OF MDW AND GYY...THE BROKEN CIGS ARE LIKELY TO BE MORE TEMPORARY...WITH MORNING MODEL TRAJECTORIES BEING MORE FROM THE EAST AS OPPOSED TO THE NORTH/NORTHEAST AND THE HEART OF THE LAKE. A COUPLE UPPER LEVEL DISTURBANCES MOVING EAST OVER THE REGION THIS MORNING ARE PRODUCING SOME SCATTERED CONVONECTION OVER CENTRAL IL. THESE SHOULD CONTINUE TO PROGRESS EAST AND REMAIN SOUTH OF THE TAF SITES...HOWEVER WITH A THICK MID- LEVEL CLOUD DECK BUILDING OVER THE REGION AND GRADUAL ASCENT WITHIN THAT LAYER...ATOP A LOWER STRATOCU CLOUD LAYER...THERE MAY BE SOME SPRINKLES IN THE AREA THROUGH EARLY AFTERNOON. TONIGHT WILL SEE NORTHEAST WINDS LIGHTEN...BUT THE FLOW OFF THE LAKE AGAIN WILL POTENTIALLY STEER BACK IN MORE LAKE EFFECT CLOUDS FOR A PERIOD INTO SUNDAY MORNING...ESPEICALLY FOR GYY AIRPORT. //ORD AND MDW CONFIDENCE...UPDATED 16Z... * HIGH CONFIDENCE IN 2500-3500 FT CIGS INTO EARLY AFTERNOON. MEDIUM CONFIDENCE IN SCATTERING OF LOWER CLOUDS MID/LATE AFTN. * HIGH CONFIDENCE THAT ANY LIGHT SHOWERS WILL KEEP VISIBILITY VFR. * HIGH CONFIDENCE IN WIND TRENDS. RATZER //OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z... SUNDAY NIGHT-MONDAY...VFR. TUESDAY...CHC OF -RA. MVFR POSSIBLE. WEDNESDAY-FRIDAY...VFR. MTF && .MARINE... 212 AM CDT NORTHERLY WINDS CONTINUE OVER THE LAKE...NOW GOING ON ALMOST A WEEK STRAIGHT FROM THAT DIRECTION. THE RIDGE AXIS FROM WESTERN QUEBEC TO NORTHERN IL WILL PUSH OVER THE LAKE BY LATER SUNDAY AND PERSIST INTO THE DAY MONDAY...BRINGING LIGHT WINDS. BEFORE THAT TIME...THE NORTHERLY WINDS AND WAVES WILL SLOWLY DIMINISH TODAY. WAVES OF 4 TO 5 FT WILL REMAIN POSSIBLE IN THE NEARSHORE AREAS OF IL AND IN EVEN AFTER THE SMALL CRAFT ADVISORY EXPIRATION...BUT THAT SHOULD BE ON THE UPPER END OF WAVE HEIGHTS...SO NO EXTENSION IN THE HEADLINE PLANNED AT THIS TIME. AFTER THE RIDGE AXIS PASSES...SOUTHERLY WINDS WILL RETURN OVER THE LAKE AND INCREASE ON TUESDAY AS A LOW PROGRESSES EAST ACROSS THE CANADIAN PRAIRIE PROVINCES. A COLD FRONT EXTENDING SOUTH FROM THIS WILL MOVE EAST OVER THE LAKE SOMETIME TUESDAY NIGHT OR WEDNESDAY. THIS IS NOT EXPECTED TO BE TOO POWERFUL OF A FRONT AS A STRONG LOW OFF THE EAST COAST SHOULD CAUSE THIS NORTHERN STREAM SYSTEM TO SLOW AND LIKELY WEAKEN. MTF && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...NONE. && $$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
902 AM CDT SAT NOV 3 2012 .DISCUSSION... 751 AM CDT MINOR QUICK UPDATES THIS MORNING TO ACCOUNT FOR ONGOING SHOWERS OVER AREAS ALONG AND SOUTH OF A LINE FROM PONTIAC IN ILLINOIS EAST TO FOWLER IN INDIANA. LATEST RADAR IMAGERY DEPICTING A SMALL AREA OF SHOWERS ACROSS THE FAR SOUTHERN TIER OF THE CWA OUT AHEAD OF A MID LEVEL TROUGH AXIS AND AREA OF WAA. INCREASED POPS TO ACCOUNT FOR THESE IN THE NEAR TERM...BUT WITH THESE SHOWERS TO EXIT TO THE EAST/SOUTHEAST OVER THE NEXT SEVERAL HOURS WITH MID LEVEL WINDS VEERING AND BETTER FORCING/WAA EXITING THE CWA. BEST INSTABILITY CURRENTLY RESIDES JUST SOUTH OF THE CWA WHERE RAP ANALYSIS IS SHOWING MUCAPE UP TO 250J/KG...WHERE A FEW LIGHTNING STRIKES HAVE ALSO BEEN REPORTED. PRECIP IN OUR CWA SHOULD REMAIN ONLY SHOWERS BEFORE EXITING...WITH AT MOST A FEW LIGHTNING STRIKES IF THIS WERE TO EVEN OCCUR. RODRIGUEZ //PREV DISCUSSION... 414 AM CDT LARGE SCALE PATTERN TO REMAIN ACTIVE ACROSS THE EASTERN PACIFIC...NORTH AMERICA...AND THE WESTERN ATLANTIC OVER THE NEXT SEVERAL DAYS THOUGH MODELS DO NOT SHOW ANY MAJOR WEATHER SYSTEMS AFFECTING OUR REGION. WHILE SEVERAL DISTURBANCES HAVE MOVED AND WILL CONTINUE TO MOVE ACROSS THE CONTINENT THE OVERALL PATTERN OF AN UPPER TROUGH OVER EASTERN NORTH AMERICA AND A RIDGE OVER THE EASTERN PACIFIC AND WESTERN NORTH AMERICA HAS PERSISTED FOR SEVERAL DAYS AND LOOKS TO REMAIN BASICALLY UNCHANGED UNTIL WE APPROACH MID NEXT WEEK. BY THAT TIME A RATHER SIGNIFICANT CHANGE IN THE OVERALL UPPER PATTERN IS TO HAVE GOTTEN UNDERWAY WITH THE EASTERN NORTH AMERICAN UPPER TROUGH BEING DISPLACED OFF TO THE NORTHEAST OVER THE GULF OF ST. LAWRENCE BY AN UPPER TROUGH TO DEEPEN AS A STRONG JET MAX...THE NOSE OF WHICH WAS CURRENTLY APPROACHING VANCOUVER ISLAND...DIGS SOUTH-SOUTHEAST FROM SASKATCHEWAN AND SOUTHERN MANITOBA OVER THE UPPER AND MS VALLEY...CARVING OUT A SHARP UPPER TROUGH OVER THE OH AND TN VALLEYS AND PROGRESSING EAST TO THE CENTRAL AND SOUTHERN APPALACHIANS BY LATER TUESDAY. UPSTREAM...THIS ALLOWS A STRONG BROAD UPPER RIDGE TO ADVANCE FROM THE WEST COAST TO THE ROCKIES. DURING WEDNESDAY AND THURSDAY THE EASTERN UPPER TROUGH/LOW IS PROGGED TO LIFT NORTHEASTWARD FROM THE MID ATLANTIC COAST TO SOUTHERN NEW ENGLAND...WITH THE UPPER RIDGE MOVING EAST ACROSS THE PLAINS AS A DEEP TROUGH DEVELOPS FROM B.C. SOUTH TO THE NORTHERN CA COAST. TEMPERATURES TO CONTINUE RUNNING A FEW DEGREES BELOW NORMALS THROUGH THE WEEKEND AND INTO EARLY NEXT WEEK THEN MODERATING VERY SLIGHTLY TO NEAR NORMALS FOR MID NEXT WEEK BEFORE MORE SUBSTANTIAL WARMING SPREADS EAST WITH THE UPPER RIDGE AND RAISES TEMPERATURES TO 8...POSSIBLY 10 DEGREES F ABOVE NORMAL BY LATE WEEK. NOTE HOWEVER THAT SOME OF THIS INCREASE AS COMPARED TO NORMALS IS TO TO THE FACT THAT NORMALS TEMPERATURES FALL AT ABOUT 1 DEGREE F EVERY TWO DAYS DUE TO THE INCREASINGLY SHORTER DAYS. SO...BESIDES TEMPERATURES RISING THE NORMALS WILL BE FALLING. LITTLE THREAT OF ANY PRECIPITATION THROUGH NEXT WEEK WITH THE BEST CHANCE...THOUGH STILL ONLY A SMALL ONE...TO BE DURING TUESDAY INTO TUESDAY NIGHT WHEN THERE IS THE POSSIBILITY OF SOME LIGHT RAIN OR RAIN SHOWERS AS A DISTURBANCE DROPS SOUTHEAST ACROSS THE UPPER MIDWEST INTO THE NORTHERN GREAT LAKES. OTHERWISE...ONLY A SLIGHT CHANCE OF SOME LAKE EFFECT SPRINKLES/VERY LIGHT RAIN SHOWERS NEAR LAKE MI TONIGHT. IN THE SHORT...TERM WEAK RADAR ECHOES WERE OBSERVED MOVING FROM NORTHWEST IL SOUTHEASTWARD DURING THE LATE EVENING AND EARLY DURING THE OVERNIGHT BUT THEY HAVE DISSIPATED OVER THE LAST COUPLE HOURS. MEANWHILE...AS ANTICIPATED LAST NIGHT...FORCING HAD SHIFTED SOUTH TO NORTHEAST MO AND CENTRAL IL AHEAD OF A SHORT WAVE MOVING EAST FROM EASTERN KS AND NE TO IA AND MO. THIS FORCING IS ALONG A STRONG BAROCLINIC ZONE /PER 03.00Z RAOBS 850 HPA TEMPERATURES OF +12C AND +17C AT TOP AND SGF RESPECTIVELY... WITH MPX AT 0C AND GRB -6C/ THAT EXTENDS NW-SE ACROSS IA AND IL TO THE LOWER OH VALLEY. THIS FORCING HAS RESULTED IN ELEVATED CONVECTION BREAKING OUT ACROSS CENTRAL IL SOUTH OF U.S. 136. THE SHORT WAVE IS PROGGED TO CONTINUE EASTWARD ACROSS THE MID MS VALLEY TODAY THOUGH WEAKEN AS IT DOES. WITH THE MAIN FORCING REMAINING ACROSS CENTRAL IL ONLY THE EXTREME SOUTHERN FRINGE OF THE LOCAL FORECAST AREA WILL HAVE A SLIGHT CHANCE OF A A FEW SHOWERS THIS MORNING. LOW LEVEL FLOW OVER SOUTHERN LAKE MI HAS BECOME RATER LIGHT EAST- NORTHEAST. WHILE LAKE EFFECT CLOUDS CONTINUE TO BE GENERATED BY THE COOL AIR FLOWING OVER THE RELATIVELY WARM WATER THE SHORT FETCH AND SUPPRESSED EQUILIBRIUM LEVEL WILL PREVENT ANY LAKE EFFECT SHOWERS TODAY. TONIGHT...LOW LEVEL FLOW RETURNS TO NORTH AND NORTH-NORTHEAST. THE INCREASED FETCH DOWN THE LAKE WILL ENCOURAGE ADDITIONAL LAKE EFFECT CLOUDS AND POSSIBLY SOME SHOWERS THOUGH CLOUD DEPTHS BASED ON FORECAST TEMPERATURE PROFILES OVER THE WATER TONIGHT SUGGEST THEY WOULD BE ONLY SOME SPRINKLES NEAR THE LAKE OR AT THE MOST A FEW SMALL LIGHT RAIN SHOWERS. DURING SUNDAY AND SUNDAY NIGHT A SHORT WAVE EJECTED FROM THE UPPER LOW IN THE GULF OF AK IS PROGGED TO DROP SOUTH-SOUTHEAST FROM SOUTHERN SASKATCHEWAN ACROSS THE DAKOTAS AND TO THE MID MO VALLEY. MODELS THEN TURN IT TO THE SOUTHEAST AND EAST-SOUTHEAST MONDAY AND TO THE TN VALLEY MONDAY NIGHT. THIS TRACK IS WELL REMOVED FROM THE LOCAL AREA AND ANY ASSOCIATED RAIN WILL STAY TO THE WEST THROUGH SOUTH OF THE FORECAST AREA. THE ONE CHANCE OF RAIN DURING THE NEXT SEVEN DAYS COMES ON TUESDAY INTO TUESDAY NIGHT AS A SHORT WAVE DROPS FROM MANITOBA AND WESTERN ONTARIO TO THE UPPER GREAT LAKES. BEST FORCING WITH THIS DISTURBANCE WILL BE ACROSS THE NORTH WOODS AND THE NORTHERN GREAT LAKES...WITH ONLY A SLIGHT CHANCE OF MEASURABLE RAIN AS FAR SOUTH AS NORTH CENTRAL AND NORTHEAST IL WITH JUST A SLIGHT CHANCE FURTHER S TOWARDS CENTRAL IL. TRS && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 14Z... * LAKE EFFECT MVFR CIGS 2500-3000 FT PROBABLE INTO THIS AFTERNOON AND POSSIBLY PERSISTING AT TIMES INTO TONIGHT. * SMALL CHANCE FOR SPRINKLES THROUGH EARLY AFTERNOON. RATZER //DISCUSSION...UPDATED 12Z... HIGH PRESSURE REMAINS ANCHORED FROM WESTERN ONTARIO SOUTHWARD INTO EASTERN WI. THE FLOW AROUND THIS FEATURE CONTINUES AND WILL THROUGH TODAY...MEANING NORTHEAST WINDS ACROSS THE AREA. THERE MAY BE A LITTLE LAKE EMPHASIS THIS AFTERNOON THAT COULD LEAD TO A FEW KNOT INCREASE...BUT ALL IN ALL A FAIRLY PERSISTENT NORTHEAST WIND WILL PREVAIL. THE FLOW OFF THE WARM LAKE CONTINUES TO OFFER STRATOCUMULUS CLOUDS. THESE SHOULD REMAIN BROKEN OVER ORD AND DPA FOR MUCH IF NOT THE ENTIRE MORNING WITH A GRADUAL LIFTING AND POTENTIALLY SOME SCATTERING EXPECTED THIS AFTERNOON. AS FOR THE SOUTHERN CHICAGOLAND SITES OF MDW AND GYY...THE BROKEN CIGS ARE LIKELY TO BE MORE TEMPORARY...WITH MORNING MODEL TRAJECTORIES BEING MORE FROM THE EAST AS OPPOSED TO THE NORTH/NORTHEAST AND THE HEART OF THE LAKE. A COUPLE UPPER LEVEL DISTURBANCES MOVING EAST OVER THE REGION THIS MORNING ARE PRODUCING SOME SCATTERED CONVONECTION OVER CENTRAL IL. THESE SHOULD CONTINUE TO PROGRESS EAST AND REMAIN SOUTH OF THE TAF SITES...HOWEVER WITH A THICK MID- LEVEL CLOUD DECK BUILDING OVER THE REGION AND GRADUAL ASCENT WITHIN THAT LAYER...ATOP A LOWER STRATOCU CLOUD LAYER...THERE MAY BE SOME SPRINKLES IN THE AREA THROUGH EARLY AFTERNOON. TONIGHT WILL SEE NORTHEAST WINDS LIGHTEN...BUT THE FLOW OFF THE LAKE AGAIN WILL POTENTIALLY STEER BACK IN MORE LAKE EFFECT CLOUDS FOR A PERIOD INTO SUNDAY MORNING...ESPEICALLY FOR GYY AIRPORT. //ORD AND MDW CONFIDENCE...UPDATED 14Z... * HIGH CONFIDENCE IN 2500-3500 FT CIGS THROUGH THIS MORNING...WITH MEDIUM CONFIDENCE IN SCATTERING TIME. MEDIUM CONFIDENCE IN BROKEN CIGS REMAINING EAST OF THE TERMINALS TONIGHT INTO SUN MORING. * HIGH CONFIDENCE THAT ANY LIGHT SHOWERS THIS MORNING WILL KEEP VISIBILITY VFR. * HIGH CONFIDENCE IN WIND TRENDS. RATZER //OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z... SUNDAY NIGHT-MONDAY...VFR. TUESDAY...CHC OF -RA. MVFR POSSIBLE. WEDNESDAY-FRIDAY...VFR. MTF && .MARINE... 212 AM CDT NORTHERLY WINDS CONTINUE OVER THE LAKE...NOW GOING ON ALMOST A WEEK STRAIGHT FROM THAT DIRECTION. THE RIDGE AXIS FROM WESTERN QUEBEC TO NORTHERN IL WILL PUSH OVER THE LAKE BY LATER SUNDAY AND PERSIST INTO THE DAY MONDAY...BRINGING LIGHT WINDS. BEFORE THAT TIME...THE NORTHERLY WINDS AND WAVES WILL SLOWLY DIMINISH TODAY. WAVES OF 4 TO 5 FT WILL REMAIN POSSIBLE IN THE NEARSHORE AREAS OF IL AND IN EVEN AFTER THE SMALL CRAFT ADVISORY EXPIRATION...BUT THAT SHOULD BE ON THE UPPER END OF WAVE HEIGHTS...SO NO EXTENSION IN THE HEADLINE PLANNED AT THIS TIME. AFTER THE RIDGE AXIS PASSES...SOUTHERLY WINDS WILL RETURN OVER THE LAKE AND INCREASE ON TUESDAY AS A LOW PROGRESSES EAST ACROSS THE CANADIAN PRAIRIE PROVINCES. A COLD FRONT EXTENDING SOUTH FROM THIS WILL MOVE EAST OVER THE LAKE SOMETIME TUESDAY NIGHT OR WEDNESDAY. THIS IS NOT EXPECTED TO BE TOO POWERFUL OF A FRONT AS A STRONG LOW OFF THE EAST COAST SHOULD CAUSE THIS NORTHERN STREAM SYSTEM TO SLOW AND LIKELY WEAKEN. MTF && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS UNTIL 11 AM SATURDAY. && $$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
801 AM CDT SAT NOV 3 2012 .DISCUSSION... 751 AM CDT MINOR QUICK UPDATES THIS MORNING TO ACCOUNT FOR ONGOING SHOWERS OVER AREAS ALONG AND SOUTH OF A LINE FROM PONTIAC IN ILLINOIS EAST TO FOWLER IN INDIANA. LATEST RADAR IMAGERY DEPICTING A SMALL AREA OF SHOWERS ACROSS THE FAR SOUTHERN TIER OF THE CWA OUT AHEAD OF A MID LEVEL TROUGH AXIS AND AREA OF WAA. INCREASED POPS TO ACCOUNT FOR THESE IN THE NEAR TERM...BUT WITH THESE SHOWERS TO EXIT TO THE EAST/SOUTHEAST OVER THE NEXT SEVERAL HOURS WITH MID LEVEL WINDS VEERING AND BETTER FORCING/WAA EXITING THE CWA. BEST INSTABILITY CURRENTLY RESIDES JUST SOUTH OF THE CWA WHERE RAP ANALYSIS IS SHOWING MUCAPE UP TO 250J/KG...WHERE A FEW LIGHTNING STRIKES HAVE ALSO BEEN REPORTED. PRECIP IN OUR CWA SHOULD REMAIN ONLY SHOWERS BEFORE EXITING...WITH AT MOST A FEW LIGHTNING STRIKES IF THIS WERE TO EVEN OCCUR. RODRIGUEZ && .PREV DISCUSSION... 414 AM CDT LARGE SCALE PATTERN TO REMAIN ACTIVE ACROSS THE EASTERN PACIFIC...NORTH AMERICA...AND THE WESTERN ATLANTIC OVER THE NEXT SEVERAL DAYS THOUGH MODELS DO NOT SHOW ANY MAJOR WEATHER SYSTEMS AFFECTING OUR REGION. WHILE SEVERAL DISTURBANCES HAVE MOVED AND WILL CONTINUE TO MOVE ACROSS THE CONTINENT THE OVERALL PATTERN OF AN UPPER TROUGH OVER EASTERN NORTH AMERICA AND A RIDGE OVER THE EASTERN PACIFIC AND WESTERN NORTH AMERICA HAS PERSISTED FOR SEVERAL DAYS AND LOOKS TO REMAIN BASICALLY UNCHANGED UNTIL WE APPROACH MID NEXT WEEK. BY THAT TIME A RATHER SIGNIFICANT CHANGE IN THE OVERALL UPPER PATTERN IS TO HAVE GOTTEN UNDERWAY WITH THE EASTERN NORTH AMERICAN UPPER TROUGH BEING DISPLACED OFF TO THE NORTHEAST OVER THE GULF OF ST. LAWRENCE BY AN UPPER TROUGH TO DEEPEN AS A STRONG JET MAX...THE NOSE OF WHICH WAS CURRENTLY APPROACHING VANCOUVER ISLAND...DIGS SOUTH-SOUTHEAST FROM SASKATCHEWAN AND SOUTHERN MANITOBA OVER THE UPPER AND MS VALLEY...CARVING OUT A SHARP UPPER TROUGH OVER THE OH AND TN VALLEYS AND PROGRESSING EAST TO THE CENTRAL AND SOUTHERN APPALACHIANS BY LATER TUESDAY. UPSTREAM...THIS ALLOWS A STRONG BROAD UPPER RIDGE TO ADVANCE FROM THE WEST COAST TO THE ROCKIES. DURING WEDNESDAY AND THURSDAY THE EASTERN UPPER TROUGH/LOW IS PROGGED TO LIFT NORTHEASTWARD FROM THE MID ATLANTIC COAST TO SOUTHERN NEW ENGLAND...WITH THE UPPER RIDGE MOVING EAST ACROSS THE PLAINS AS A DEEP TROUGH DEVELOPS FROM B.C. SOUTH TO THE NORTHERN CA COAST. TEMPERATURES TO CONTINUE RUNNING A FEW DEGREES BELOW NORMALS THROUGH THE WEEKEND AND INTO EARLY NEXT WEEK THEN MODERATING VERY SLIGHTLY TO NEAR NORMALS FOR MID NEXT WEEK BEFORE MORE SUBSTANTIAL WARMING SPREADS EAST WITH THE UPPER RIDGE AND RAISES TEMPERATURES TO 8...POSSIBLY 10 DEGREES F ABOVE NORMAL BY LATE WEEK. NOTE HOWEVER THAT SOME OF THIS INCREASE AS COMPARED TO NORMALS IS TO TO THE FACT THAT NORMALS TEMPERATURES FALL AT ABOUT 1 DEGREE F EVERY TWO DAYS DUE TO THE INCREASINGLY SHORTER DAYS. SO...BESIDES TEMPERATURES RISING THE NORMALS WILL BE FALLING. LITTLE THREAT OF ANY PRECIPITATION THROUGH NEXT WEEK WITH THE BEST CHANCE...THOUGH STILL ONLY A SMALL ONE...TO BE DURING TUESDAY INTO TUESDAY NIGHT WHEN THERE IS THE POSSIBILITY OF SOME LIGHT RAIN OR RAIN SHOWERS AS A DISTURBANCE DROPS SOUTHEAST ACROSS THE UPPER MIDWEST INTO THE NORTHERN GREAT LAKES. OTHERWISE...ONLY A SLIGHT CHANCE OF SOME LAKE EFFECT SPRINKLES/VERY LIGHT RAIN SHOWERS NEAR LAKE MI TONIGHT. IN THE SHORT...TERM WEAK RADAR ECHOES WERE OBSERVED MOVING FROM NORTHWEST IL SOUTHEASTWARD DURING THE LATE EVENING AND EARLY DURING THE OVERNIGHT BUT THEY HAVE DISSIPATED OVER THE LAST COUPLE HOURS. MEANWHILE...AS ANTICIPATED LAST NIGHT...FORCING HAD SHIFTED SOUTH TO NORTHEAST MO AND CENTRAL IL AHEAD OF A SHORT WAVE MOVING EAST FROM EASTERN KS AND NE TO IA AND MO. THIS FORCING IS ALONG A STRONG BAROCLINIC ZONE /PER 03.00Z RAOBS 850 HPA TEMPERATURES OF +12C AND +17C AT TOP AND SGF RESPECTIVELY... WITH MPX AT 0C AND GRB -6C/ THAT EXTENDS NW-SE ACROSS IA AND IL TO THE LOWER OH VALLEY. THIS FORCING HAS RESULTED IN ELEVATED CONVECTION BREAKING OUT ACROSS CENTRAL IL SOUTH OF U.S. 136. THE SHORT WAVE IS PROGGED TO CONTINUE EASTWARD ACROSS THE MID MS VALLEY TODAY THOUGH WEAKEN AS IT DOES. WITH THE MAIN FORCING REMAINING ACROSS CENTRAL IL ONLY THE EXTREME SOUTHERN FRINGE OF THE LOCAL FORECAST AREA WILL HAVE A SLIGHT CHANCE OF A A FEW SHOWERS THIS MORNING. LOW LEVEL FLOW OVER SOUTHERN LAKE MI HAS BECOME RATER LIGHT EAST- NORTHEAST. WHILE LAKE EFFECT CLOUDS CONTINUE TO BE GENERATED BY THE COOL AIR FLOWING OVER THE RELATIVELY WARM WATER THE SHORT FETCH AND SUPPRESSED EQUILIBRIUM LEVEL WILL PREVENT ANY LAKE EFFECT SHOWERS TODAY. TONIGHT...LOW LEVEL FLOW RETURNS TO NORTH AND NORTH-NORTHEAST. THE INCREASED FETCH DOWN THE LAKE WILL ENCOURAGE ADDITIONAL LAKE EFFECT CLOUDS AND POSSIBLY SOME SHOWERS THOUGH CLOUD DEPTHS BASED ON FORECAST TEMPERATURE PROFILES OVER THE WATER TONIGHT SUGGEST THEY WOULD BE ONLY SOME SPRINKLES NEAR THE LAKE OR AT THE MOST A FEW SMALL LIGHT RAIN SHOWERS. DURING SUNDAY AND SUNDAY NIGHT A SHORT WAVE EJECTED FROM THE UPPER LOW IN THE GULF OF AK IS PROGGED TO DROP SOUTH-SOUTHEAST FROM SOUTHERN SASKATCHEWAN ACROSS THE DAKOTAS AND TO THE MID MO VALLEY. MODELS THEN TURN IT TO THE SOUTHEAST AND EAST-SOUTHEAST MONDAY AND TO THE TN VALLEY MONDAY NIGHT. THIS TRACK IS WELL REMOVED FROM THE LOCAL AREA AND ANY ASSOCIATED RAIN WILL STAY TO THE WEST THROUGH SOUTH OF THE FORECAST AREA. THE ONE CHANCE OF RAIN DURING THE NEXT SEVEN DAYS COMES ON TUESDAY INTO TUESDAY NIGHT AS A SHORT WAVE DROPS FROM MANITOBA AND WESTERN ONTARIO TO THE UPPER GREAT LAKES. BEST FORCING WITH THIS DISTURBANCE WILL BE ACROSS THE NORTH WOODS AND THE NORTHERN GREAT LAKES...WITH ONLY A SLIGHT CHANCE OF MEASURABLE RAIN AS FAR SOUTH AS NORTH CENTRAL AND NORTHEAST IL WITH JUST A SLIGHT CHANCE FURTHER S TOWARDS CENTRAL IL. TRS && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 12Z... * LAKE EFFECT MVFR CIGS PROBABLE INTO THIS AFTERNOON AND POSSIBLY PERSISTING AT TIMES INTO TONIGHT. * SMALL CHANCE FOR SPRINKLES THROUGH EARLY AFTERNOON. //DISCUSSION...UPDATED 12Z... HIGH PRESSURE REMAINS ANCHORED FROM WESTERN ONTARIO SOUTHWARD INTO EASTERN WI. THE FLOW AROUND THIS FEATURE CONTINUES AND WILL THROUGH TODAY...MEANING NORTHEAST WINDS ACROSS THE AREA. THERE MAY BE A LITTLE LAKE EMPHASIS THIS AFTERNOON THAT COULD LEAD TO A FEW KNOT INCREASE...BUT ALL IN ALL A FAIRLY PERSISTENT NORTHEAST WIND WILL PREVAIL. THE FLOW OFF THE WARM LAKE CONTINUES TO OFFER STRATOCUMULUS CLOUDS. THESE SHOULD REMAIN BROKEN OVER ORD AND DPA FOR MUCH IF NOT THE ENTIRE MORNING WITH A GRADUAL LIFTING AND POTENTIALLY SOME SCATTERING EXPECTED THIS AFTERNOON. AS FOR THE SOUTHERN CHICAGOLAND SITES OF MDW AND GYY...THE BROKEN CIGS ARE LIKELY TO BE MORE TEMPORARY...WITH MORNING MODEL TRAJECTORIES BEING MORE FROM THE EAST AS OPPOSED TO THE NORTH/NORTHEAST AND THE HEART OF THE LAKE. A COUPLE UPPER LEVEL DISTURBANCES MOVING EAST OVER THE REGION THIS MORNING ARE PRODUCING SOME SCATTERED CONVONECTION OVER CENTRAL IL. THESE SHOULD CONTINUE TO PROGRESS EAST AND REMAIN SOUTH OF THE TAF SITES...HOWEVER WITH A THICK MID- LEVEL CLOUD DECK BUILDING OVER THE REGION AND GRADUAL ASCENT WITHIN THAT LAYER...ATOP A LOWER STRATOCU CLOUD LAYER...THERE MAY BE SOME SPRINKLES IN THE AREA THROUGH EARLY AFTERNOON. TONIGHT WILL SEE NORTHEAST WINDS LIGHTEN...BUT THE FLOW OFF THE LAKE AGAIN WILL POTENTIALLY STEER BACK IN MORE LAKE EFFECT CLOUDS FOR A PERIOD INTO SUNDAY MORNING...ESPEICALLY FOR GYY AIRPORT. //ORD AND MDW CONFIDENCE...UPDATED 12Z... * HIGH CONFIDENCE IN 2500-3500 FT CIGS THROUGH THIS MORNING...WITH MEDIUM CONFIDENCE IN SCATTERING TIME. MEDIUM CONFIDENCE IN BROKEN CIGS REMAINING EAST OF THE TERMINALS TONIGHT INTO SUN MORING. * HIGH CONFIDENCE THAT ANY LIGHT SHOWERS THIS MORNING WILL KEEP VISIBILITY VFR. * HIGH CONFIDENCE IN WIND TRENDS. //OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z... SUNDAY NIGHT-MONDAY...VFR. TUESDAY...CHC OF -RA. MVFR POSSIBLE. WEDNESDAY-FRIDAY...VFR. MTF && .MARINE... 212 AM CDT NORTHERLY WINDS CONTINUE OVER THE LAKE...NOW GOING ON ALMOST A WEEK STRAIGHT FROM THAT DIRECTION. THE RIDGE AXIS FROM WESTERN QUEBEC TO NORTHERN IL WILL PUSH OVER THE LAKE BY LATER SUNDAY AND PERSIST INTO THE DAY MONDAY...BRINGING LIGHT WINDS. BEFORE THAT TIME...THE NORTHERLY WINDS AND WAVES WILL SLOWLY DIMINISH TODAY. WAVES OF 4 TO 5 FT WILL REMAIN POSSIBLE IN THE NEARSHORE AREAS OF IL AND IN EVEN AFTER THE SMALL CRAFT ADVISORY EXPIRATION...BUT THAT SHOULD BE ON THE UPPER END OF WAVE HEIGHTS...SO NO EXTENSION IN THE HEADLINE PLANNED AT THIS TIME. AFTER THE RIDGE AXIS PASSES...SOUTHERLY WINDS WILL RETURN OVER THE LAKE AND INCREASE ON TUESDAY AS A LOW PROGRESSES EAST ACROSS THE CANADIAN PRAIRIE PROVINCES. A COLD FRONT EXTENDING SOUTH FROM THIS WILL MOVE EAST OVER THE LAKE SOMETIME TUESDAY NIGHT OR WEDNESDAY. THIS IS NOT EXPECTED TO BE TOO POWERFUL OF A FRONT AS A STRONG LOW OFF THE EAST COAST SHOULD CAUSE THIS NORTHERN STREAM SYSTEM TO SLOW AND LIKELY WEAKEN. MTF && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS UNTIL 11 AM SATURDAY. && $$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
214 AM CDT SAT NOV 3 2012 .DISCUSSION... 329 PM CDT MAIN FORECAST CHALLENGES ARE WITH PERSISTENT LAKE EFFECT CLOUD COVER AS WELL AS POSSIBLE LIGHT RAIN SHOWERS. CURRENT SATELLITE IMAGERY CONTINUES TO SHOW LAKE EFFECT CLOUD COVER TO MOVE DOWN LAKE MICHIGAN THIS AFTERNOON AND SPILLING INTO NORTHWEST INDIANA...AS HIGH LEVEL CLOUD COVER CONTINUES TO WORK ITS WAY EAST ACROSS NORTHERN ILLINOIS. MEANWHILE...RADAR IMAGERY DEPICTING SOME LIGHT SHOWERS ALSO STILL DEVELOPING OVER THE SOUTHERN HALF OF THE LAKE AND MOVING INTO PORTER COUNTY IN NORTHWEST INDIANA. THESE LIGHT SHOWERS ARE DUE IN PART TO A LONG FETCH DOWN THE LAKE WITH SUFFICIENT DELTA TS AND CONVERGENCE NOTED ON OBS/LATEST RAP ANALYSIS. EXPECT THESE SHOWERS TO CONTINUE THIS AFTERNOON AND POSSIBLY INTO THIS EVENING WITH A SLIGHT SHIFT MORE WESTWARD INTO LAKE COUNTY IN NORTHWEST INDIANA AS BOUNDARY LAYER SHIFTS MORE NORTH/NORTHEAST. ALTHOUGH DURING THIS TIME...LATEST FORECAST SOUNDINGS OVER THE LAKE SHOWING SOME WARMING IN THE COLUMN AND A LOWERING OF EQUILIBRIUM HEIGHTS. THIS SHOULD HELP TO STIFLE THE DEVELOPMENT WHICH WE HAVE SEEN ALL DAY...WITH ONLY PRIMARILY LAKE EFFECT CLOUD COVER CONTINUING TO DEVELOP. ALTHOUGH...THERE IS SOME HIGH RES GUIDANCE THAT DOES INDICATE SOME PERSISTENT LIGHT QPF ACROSS THE LAKE AND NEAR THE SHORES TONIGHT AND INTO SATURDAY MORNING...BUT AM NOT COMPLETELY SOLD ON THIS IDEA AS OF YET DUE TO THE PREVIOUSLY MENTIONED WARMING TRENDS. SO HAVE SLIGHT CHANCE POPS GOING INTO THIS EVENING BUT THEN DECREASE OVERNIGHT INTO SATURDAY. IF THERE WERE TO BE ANY SHOWERS TO DEVELOP IT WOULD BE IN THE FORM OF SPRINKLES...FORMING ON THE FRINGE OF BUILDING HIGH PRESSURE. CURRENT WAA ACROSS THE PLAINS WILL SLOWLY SHIFT EAST INTO CENTRAL ILLINOIS TONIGHT OUT AHEAD OF A MID LEVEL TROUGH/SURFACE LOW TO THE WEST. THIS SHOULD HELP CLOUD COVER TO CONTINUE TO SPREAD EAST ACROSS THE ENTIRE CWA TONIGHT...WITH PARTLY CLOUDY SKIES BECOMING MORE CLOUDY. IT DOES APPEAR THE EXTENT OF THE WAA IS WEAKER TONIGHT AND MORE DEFINED FURTHER SOUTH...WITH ANY PRECIP THAT DEVELOPS TONIGHT IN RESPONSE TO THIS FORCING TO STAY SOUTH OF THE CWA. THIS TROUGH/SURFACE REFLECTION WILL CONTINUE EAST ON SATURDAY WITH SOME OF THIS MOISTURE TRYING TO INCH ITS WAY FURTHER NORTH...WITH A SLIGHT CHANCE FOR SHOWERS ON SATURDAY MAINLY ACROSS THE FAR SOUTHERN TIER OF THE CWA. AS HIGHER PRESSURE BUILDS OVERHEAD THROUGH THE REMAINDER OF THE WEEKEND...EXPECT DRY CONDITIONS WITH SIMILAR TEMPS IN THE 40S FOR SATURDAY AND SUNDAY. ALTHOUGH WITH SEVERAL MID LEVEL FEATURES TRAVERSING THE REGION...SOME MID LEVEL MOISTURE SHOULD MOVE OVERHEAD AND BRING SOME CLOUDY CONDITIONS ACROSS THE CWA THIS WEEKEND. RODRIGUEZ && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 06Z... * LAKE EFFECT MVFR CIGS INTO THIS AFTERNOON AND POSSIBLY PERSISTING AT TIMES INTO TONIGHT. * SMALL CHANCE FOR A LIGHT SHOWER THIS MORNING. //DISCUSSION...UPDATED 06Z... HIGH PRESSURE RIDGE IS EXTENDING FROM WESTERN ONTARIO THROUGH NORTHERN IL EARLY THIS MORNING. NORTHEAST FLOW AHEAD OF THIS WILL CONTINUE TO FUNNEL LAKE EFFECT CLOUDS INTO CHICAGOLAND TAF SITES AND LIKELY RFD BY LATER THIS MORNING. THE CLOUDS SHOULD STAY AT CONSTANT HEIGHTS BETWEEN 2200 AND 3500 FT THROUGHOUT THE ENTIRE MORNING LOOKING AT OBSERVATIONS/AMDAR SOUNDINGS AND FORECAST PROJECTIONS. AN UPPER LEVEL DISTURBANCE SLIDING TO THE SOUTHEAST JUST WEST AND SOUTH OF THE AREA WILL PROMOTE A BLANKET OF MID-LEVEL CLOUDS. GRADUAL ASCENT WITHIN THIS AREA HAS ALREADY PRODUCED SOME LIGHT ECHOES. WITH THIS PASSING OVER THE LOWER LAKE EFFECT CLOUDS...IT IS POSSIBLE FOR SOME SEEDER-FEEDER TYPE PROCESSES TO PRODUCE A LIGHT SHOWER OR SOME SPRINKLES. OUTSIDE OF THAT SMALL CHANCE...THE TAF PERIOD WILL BE DRY WITH NORTHEAST WINDS PERSISTING INTO TONIGHT. LAKE EFFECT CLOUDS LOOK TO POSSIBLY RE-EXPAND TONIGHT...BUT BE MORE FOCUSED TOWARD NORTHWEST IN DUE TO MORE OF A NORTHERLY BOUNDARY LAYER COMPONENT. //ORD AND MDW CONFIDENCE...UPDATED 06Z... * HIGH CONFIDENCE IN SKY TRENDS THROUGH THIS MORNING...WITH MEDIUM CONFIDENCE IN SCATTERING TIME. MEDIUM CONFIDENCE IN BROKEN CIGS REMAINING EAST OF THE TERMINALS TONIGHT. * HIGH CONFIDENCE IN CIGS REMAINING ABOVE 1700 FT. * HIGH CONFIDENCE THAT ANY LIGHT SHOWERS THIS MORNING WILL KEEP VISIBILITY VFR. //OUTLOOK FOR ORD/MDW FOR 12Z SUNDAY-12Z THURSDAY...UPDATED 00Z... SUNDAY...AM MVFR CIGS POSSIBLE...OTHERWISE VFR. MONDAY...VFR. TUESDAY...SLIGHT CHANCE OF -SHRA. MVFR POSSIBLE. WEDNESDAY AND THURSDAY...VFR. MTF/IZZI && .MARINE... 212 AM CDT NORTHERLY WINDS CONTINUE OVER THE LAKE...NOW GOING ON ALMOST A WEEK STRAIGHT FROM THAT DIRECTION. THE RIDGE AXIS FROM WESTERN QUEBEC TO NORTHERN IL WILL PUSH OVER THE LAKE BY LATER SUNDAY AND PERSIST INTO THE DAY MONDAY...BRINGING LIGHT WINDS. BEFORE THAT TIME...THE NORTHERLY WINDS AND WAVES WILL SLOWLY DIMINISH TODAY. WAVES OF 4 TO 5 FT WILL REMAIN POSSIBLE IN THE NEARSHORE AREAS OF IL AND IN EVEN AFTER THE SMALL CRAFT ADVISORY EXPIRATION...BUT THAT SHOULD BE ON THE UPPER END OF WAVE HEIGHTS...SO NO EXTENSION IN THE HEADLINE PLANNED AT THIS TIME. AFTER THE RIDGE AXIS PASSES...SOUTHERLY WINDS WILL RETURN OVER THE LAKE AND INCREASE ON TUESDAY AS A LOW PROGRESSES EAST ACROSS THE CANADIAN PRAIRIE PROVINCES. A COLD FRONT EXTENDING SOUTH FROM THIS WILL MOVE EAST OVER THE LAKE SOMETIME TUESDAY NIGHT OR WEDNESDAY. THIS IS NOT EXPECTED TO BE TOO POWERFUL OF A FRONT AS A STRONG LOW OFF THE EAST COAST SHOULD CAUSE THIS NORTHERN STREAM SYSTEM TO SLOW AND LIKELY WEAKEN. MTF && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS UNTIL 11 AM SATURDAY. && $$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1243 AM CDT SAT NOV 3 2012 .DISCUSSION... 329 PM CDT MAIN FORECAST CHALLENGES ARE WITH PERSISTENT LAKE EFFECT CLOUD COVER AS WELL AS POSSIBLE LIGHT RAIN SHOWERS. CURRENT SATELLITE IMAGERY CONTINUES TO SHOW LAKE EFFECT CLOUD COVER TO MOVE DOWN LAKE MICHIGAN THIS AFTERNOON AND SPILLING INTO NORTHWEST INDIANA...AS HIGH LEVEL CLOUD COVER CONTINUES TO WORK ITS WAY EAST ACROSS NORTHERN ILLINOIS. MEANWHILE...RADAR IMAGERY DEPICTING SOME LIGHT SHOWERS ALSO STILL DEVELOPING OVER THE SOUTHERN HALF OF THE LAKE AND MOVING INTO PORTER COUNTY IN NORTHWEST INDIANA. THESE LIGHT SHOWERS ARE DUE IN PART TO A LONG FETCH DOWN THE LAKE WITH SUFFICIENT DELTA TS AND CONVERGENCE NOTED ON OBS/LATEST RAP ANALYSIS. EXPECT THESE SHOWERS TO CONTINUE THIS AFTERNOON AND POSSIBLY INTO THIS EVENING WITH A SLIGHT SHIFT MORE WESTWARD INTO LAKE COUNTY IN NORTHWEST INDIANA AS BOUNDARY LAYER SHIFTS MORE NORTH/NORTHEAST. ALTHOUGH DURING THIS TIME...LATEST FORECAST SOUNDINGS OVER THE LAKE SHOWING SOME WARMING IN THE COLUMN AND A LOWERING OF EQUILIBRIUM HEIGHTS. THIS SHOULD HELP TO STIFLE THE DEVELOPMENT WHICH WE HAVE SEEN ALL DAY...WITH ONLY PRIMARILY LAKE EFFECT CLOUD COVER CONTINUING TO DEVELOP. ALTHOUGH...THERE IS SOME HIGH RES GUIDANCE THAT DOES INDICATE SOME PERSISTENT LIGHT QPF ACROSS THE LAKE AND NEAR THE SHORES TONIGHT AND INTO SATURDAY MORNING...BUT AM NOT COMPLETELY SOLD ON THIS IDEA AS OF YET DUE TO THE PREVIOUSLY MENTIONED WARMING TRENDS. SO HAVE SLIGHT CHANCE POPS GOING INTO THIS EVENING BUT THEN DECREASE OVERNIGHT INTO SATURDAY. IF THERE WERE TO BE ANY SHOWERS TO DEVELOP IT WOULD BE IN THE FORM OF SPRINKLES...FORMING ON THE FRINGE OF BUILDING HIGH PRESSURE. CURRENT WAA ACROSS THE PLAINS WILL SLOWLY SHIFT EAST INTO CENTRAL ILLINOIS TONIGHT OUT AHEAD OF A MID LEVEL TROUGH/SURFACE LOW TO THE WEST. THIS SHOULD HELP CLOUD COVER TO CONTINUE TO SPREAD EAST ACROSS THE ENTIRE CWA TONIGHT...WITH PARTLY CLOUDY SKIES BECOMING MORE CLOUDY. IT DOES APPEAR THE EXTENT OF THE WAA IS WEAKER TONIGHT AND MORE DEFINED FURTHER SOUTH...WITH ANY PRECIP THAT DEVELOPS TONIGHT IN RESPONSE TO THIS FORCING TO STAY SOUTH OF THE CWA. THIS TROUGH/SURFACE REFLECTION WILL CONTINUE EAST ON SATURDAY WITH SOME OF THIS MOISTURE TRYING TO INCH ITS WAY FURTHER NORTH...WITH A SLIGHT CHANCE FOR SHOWERS ON SATURDAY MAINLY ACROSS THE FAR SOUTHERN TIER OF THE CWA. AS HIGHER PRESSURE BUILDS OVERHEAD THROUGH THE REMAINDER OF THE WEEKEND...EXPECT DRY CONDITIONS WITH SIMILAR TEMPS IN THE 40S FOR SATURDAY AND SUNDAY. ALTHOUGH WITH SEVERAL MID LEVEL FEATURES TRAVERSING THE REGION...SOME MID LEVEL MOISTURE SHOULD MOVE OVERHEAD AND BRING SOME CLOUDY CONDITIONS ACROSS THE CWA THIS WEEKEND. RODRIGUEZ && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 06Z... * LAKE EFFECT MVFR CIGS INTO THIS AFTERNOON AND POSSIBLY PERSISTING AT TIMES INTO TONIGHT. * SMALL CHANCE FOR A LIGHT SHOWER THIS MORNING. //DISCUSSION...UPDATED 06Z... HIGH PRESSURE RIDGE IS EXTENDING FROM WESTERN ONTARIO THROUGH NORTHERN IL EARLY THIS MORNING. NORTHEAST FLOW AHEAD OF THIS WILL CONTINUE TO FUNNEL LAKE EFFECT CLOUDS INTO CHICAGOLAND TAF SITES AND LIKELY RFD BY LATER THIS MORNING. THE CLOUDS SHOULD STAY AT CONSTANT HEIGHTS BETWEEN 2200 AND 3500 FT THROUGHOUT THE ENTIRE MORNING LOOKING AT OBSERVATIONS/AMDAR SOUNDINGS AND FORECAST PROJECTIONS. AN UPPER LEVEL DISTURBANCE SLIDING TO THE SOUTHEAST JUST WEST AND SOUTH OF THE AREA WILL PROMOTE A BLANKET OF MID-LEVEL CLOUDS. GRADUAL ASCENT WITHIN THIS AREA HAS ALREADY PRODUCED SOME LIGHT ECHOES. WITH THIS PASSING OVER THE LOWER LAKE EFFECT CLOUDS...IT IS POSSIBLE FOR SOME SEEDER-FEEDER TYPE PROCESSES TO PRODUCE A LIGHT SHOWER OR SOME SPRINKLES. OUTSIDE OF THAT SMALL CHANCE...THE TAF PERIOD WILL BE DRY WITH NORTHEAST WINDS PERSISTING INTO TONIGHT. LAKE EFFECT CLOUDS LOOK TO POSSIBLY RE-EXPAND TONIGHT...BUT BE MORE FOCUSED TOWARD NORTHWEST IN DUE TO MORE OF A NORTHERLY BOUNDARY LAYER COMPONENT. //ORD AND MDW CONFIDENCE...UPDATED 06Z... * HIGH CONFIDENCE IN SKY TRENDS THROUGH THIS MORNING...WITH MEDIUM CONFIDENCE IN SCATTERING TIME. MEDIUM CONFIDENCE IN BROKEN CIGS REMAINING EAST OF THE TERMINALS TONIGHT. * HIGH CONFIDENCE IN CIGS REMAINING ABOVE 1700 FT. * HIGH CONFIDENCE THAT ANY LIGHT SHOWERS THIS MORNING WILL KEEP VISIBILITY VFR. //OUTLOOK FOR ORD/MDW FOR 12Z SUNDAY-12Z THURSDAY...UPDATED 00Z... SUNDAY...AM MVFR CIGS POSSIBLE...OTHERWISE VFR. MONDAY...VFR. TUESDAY...SLIGHT CHANCE OF -SHRA. MVFR POSSIBLE. WEDNESDAY AND THURSDAY...VFR. MTF/IZZI && .MARINE... 217 PM CDT BROAD AREA OF LOW PRESSURE CENTERED ACROSS NORTHEAST QUEBEC WILL CONTINUE TO WEAKEN THE INFLUENCE ACROSS THE WESTERN GREAT LAKES THROUGH TONIGHT INTO SATURDAY...MEANWHILE A RIDGE OF HIGH PRESSURE REMAINS CENTERED ACROSS WESTERN ONTARIO STRETCHING SOUTH THROUGH THE UPPER MISSISSIPPI VALLEY. THIS RIDGE WILL REMAIN NEARLY STATIONARY...WHICH WILL ALLOW A PROLONGED PERIOD OF NORTH FLOW ACROSS LAKE MICHIGAN. GUIDANCE HAS INDICATED THAT A DECENT GRADIENT WILL REMAIN ACROSS LAKE MICHIGAN THROUGH TONIGHT...AND POSSIBLY CONTINUE THROUGH SATURDAY. THIS WILL MOST LIKELY KEEP WINDS UP IN THE 20 TO 25 KT CATEGORY. THE COMBINATION OF CONTINUED COLD AIR...NORTH WINDS AND RELATIVELY WARM LAKE MICHIGAN WATERS WILL RESULT IN WAVES REMAINING ELEVATED. BASED ON THIS SETUP HAVE OPTED TO CONTINUE THE SMALL CRAFT ADVISORY THROUGH TONIGHT AND INTO AT LEAST MID MORNING SATURDAY. BY LATE SATURDAY MORNING WAVES IN THE NEARSHORE SHOULD SUBSIDE ENOUGH TO ALLOW THE ADVISORY TO COME DOWN. GUIDANCE WAS ALSO INDICATING THAT WINDS MAY BEGIN TO TURN NORTHEAST THROUGH A PERIOD OF TIME SATURDAY AFTERNOON/EVENING...AND DIMINISH TO SPEEDS AROUND 10 TO 20 KT. A WEAK AREA OF LOW PRESSURE IS NOW EXPECTED TO PASS WELL SOUTH OF SOUTHERN LAKE MICHIGAN...HOWEVER WINDS ACROSS THE SOUTHERN TIP OF THE LAKE MAY TURN MORE EASTERLY. IF THIS SCENARIO DEVELOPS THE WAVES MAY REMAIN CHOPPY OR CLOSE TO SMALL CRAFT CONDITIONS THROUGH SATURDAY AFTERNOON FOR THE CHICAGO HARBOR AREA. HIGH PRESSURE BY THE END OF THE WEEKEND WILL DRIFT EAST AND ALLOW WINDS TO CONTINUE TO DIMINISH AND TURN EAST THEN SOUTH BY EARLY NEXT WEEK. A LOW PRESSURE IS EXPECTED TO SLIDE ACROSS WESTERN ONTARIO WITH AN INCREASING GRADIENT AND GUSTY WINDS BY TUESDAY. THIS WILL ALLOW WAVES TO STEADILY BUILD AGAIN LATE MONDAY THROUGH TUESDAY. BEACHLER && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS UNTIL 11 AM SATURDAY. && $$
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1216 PM CDT SAT NOV 3 2012 .AVIATION... A WEAK UPPER LEVEL SYSTEM WILL PASS THROUGH THE AREA LATE TONIGHT AND EARLY SUNDAY MORNING. THIS WILL PRODUCE ANOTHER ROUND OF MID AND HIGH LEVEL CLOUDS AND POSSIBLY SOME VERY LIGHT RAIN SHOWERS OR SPRINKLES. CID HAS THE GREATEST POTENTIAL TO SEE THE LIGHT PRECIPITATION SUNDAY MORNING...BUT THE PROBABILITY IS TOO LOW TO WARRANT MENTION IN THE FORECAST. OTHERWISE...VFR CONDITIONS WILL CONTINUE THROUGH SUNDAY. SHEETS && .PREV DISCUSSION... /ISSUED 656 AM CDT SAT NOV 3 2012/ UPDATE... THE WAA THAT PRODUCED THE EARLIER SPRINKLES WITH POSSIBLY A COUPLE OF SHRA IN THE FAR SOUTH HAS SHIFTED INTO CENTRAL/EASTERN ILLINOIS. RADAR IS SHOWING PROBABLE VIRGA/MID CLOUDS ACROSS NORTHEAST IOWA AND INTO SOUTHERN WISCONSIN. CONDENSATION PRESSURE DEFICITS REMAIN HIGH PER RAP TRENDS WITH VERY WEAK FORCING AND FCST SOUNDINGS HAVE PLENTY OF DRY AIR BELOW THE CLOUDS. THE WARM START THIS MORNING WILL BE OFFSET BY THE LARGE AMOUNT OF MID LEVEL CLOUDS. MAX TEMPS HAVE BEEN LOWERED SLIGHTLY WITH THE IDEA THAT TEMPERATURES WILL BE SIMILAR TO YESTERDAY. LATE TONIGHT THE 06Z MODELS CONTINUE TO SHOW A LOWERING OF THE 850-700MB CONDENSATION PRESSURE DEFICITS WITH SOME WEAK CONVERGENCE FROM THE APPROACHING SHORTWAVE. HOWEVER...THE THETA E GRADIENT REMAINS VERY DIFFUSE. IF ANY PRECIPITATION MAKES IT INTO THE CWFA IT WOULD BE VERY LATE TONIGHT AND WOULD LIKELY BE IN THE FORM OF DECAYING SPRINKLES THAT MAY OR MAY NOT LINGER INTO SUNDAY MORNING. ..08.. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...NONE. IL...NONE. MO...NONE. && $$
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
656 AM CDT SAT NOV 3 2012 .UPDATE... THE WAA THAT PRODUCED THE EARLIER SPRINKLES WITH POSSIBLY A COUPLE OF SHRA IN THE FAR SOUTH HAS SHIFTED INTO CENTRAL/EASTERN ILLINOIS. RADAR IS SHOWING PROBABLE VIRGA/MID CLOUDS ACROSS NORTHEAST IOWA AND INTO SOUTHERN WISCONSIN. CONDENSATION PRESSURE DEFICITS REMAIN HIGH PER RAP TRENDS WITH VERY WEAK FORCING AND FCST SOUNDINGS HAVE PLENTY OF DRY AIR BELOW THE CLOUDS. THE WARM START THIS MORNING WILL BE OFFSET BY THE LARGE AMOUNT OF MID LEVEL CLOUDS. MAX TEMPS HAVE BEEN LOWERED SLIGHTLY WITH THE IDEA THAT TEMPERATURES WILL BE SIMILAR TO YESTERDAY. LATE TONIGHT THE 06Z MODELS CONTINUE TO SHOW A LOWERING OF THE 850-700MB CONDENSATION PRESSURE DEFICITS WITH SOME WEAK CONVERGENCE FROM THE APPROACHING SHORTWAVE. HOWEVER...THE THETA E GRADIENT REMAINS VERY DIFFUSE. IF ANY PRECIPITATION MAKES IT INTO THE CWFA IT WOULD BE VERY LATE TONIGHT AND WOULD LIKELY BE IN THE FORM OF DECAYING SPRINKLES THAT MAY OR MAY NOT LINGER INTO SUNDAY MORNING. ..08.. && .AVIATION... VFR WX WILL BE SEEN THROUGH 12Z/04. LOW PRESSURE WILL PASS THROUGH SOUTHERN ILLINOIS TAKING ANY PRECIPITATION THREAT WITH IT. AN APPROACHING WEAK DISTURBANCE AFT 06Z/04 MIGHT RESULT IN SOME SPRINKLES AROUND SUNRISE SUNDAY AT KCID. ..08.. && .PREV DISCUSSION... /ISSUED 319 AM CDT SAT NOV 3 2012/ SYNOPSIS... 06Z SFC ANALYSIS HAS A WEAK LOW NEAR KJLN AND ANOTHER NEAR KSPS. DISCONTINUOUS FRONTS CONNECTED THE LOWS. WEAK INVERTED TROFS EXTENDED FROM THE KJLN LOW INTO NORTHEAST MISSOURI AND INTO WESTERN IOWA. DEW POINTS WERE IN THE 40S AND 50S FROM THE SOUTHERN PLAINS INTO THE LOWER MISSISSIPPI VALLEY WITH 20S AND 30S OVER MUCH OF THE MIDWEST. RADAR SHOWED CONVECTION JUST SOUTH OF THE CWFA WITH SPRINKLES INTO THE FAR SOUTHERN PARTS OF THE CWFA. SHORT TERM...TODAY AND TONIGHT... BASED ON CURRENT RADAR AND RAP TRENDS...THE SPRINKLES ACROSS THE FAR SOUTHERN CWFA SHOULD EXIT THE AREA BY SUNRISE AS THE LLJ AND THETA E GRADIENT SHIFT EAST OF THE CWFA. IT APPEARS THAT A LONE SHRA RAN ALONG THE SOUTHERN CWFA BORDER WITH HANCOCK AND MCDONOUGH COUNTIES. ALTHOUGH IT WILL TAKE TIME...THE MID LEVEL CLOUDS SHOULD SLOWLY EXIT THE CWFA DURING THE MORNING HOURS ALLOWING FILTERED SUN TO BE SEEN DURING THE DAY. MAX TEMPERATURES SHOULD BE SIMILAR TO OR JUST A BIT WARMER THAN YESTERDAY GIVEN THE WARMER START. QUIET AND DRY CONDITIONS WILL BE SEEN THIS EVENING AS AN UPPER LEVEL DISTURBANCE DROPS SOUTHEAST TOWARD THE AREA. AFTER MIDNIGHT THIS DISTURBANCE MOVES THROUGH THE CWFA WITH 850-700MB CONDENSATION PRESSURE DEFICITS LOWERING BUT THE 1000-850MB CONDENSATION PRESSURE DEFICITS REMAIN HIGH. THERE SHOULD AGAIN BE A MID LEVEL CLOUD DECK MOVING INTO THE AREA. THE THETA E GRADIENT ASSOCIATED WITH THE DISTURBANCE IS WEAK AND VERY DIFFUSE AND THE OVERALL FORCING IS EITHER NOT THERE OR VERY WEAK. SPRINKLES LOOK QUESTIONABLE SO HAVE OPTED TO GO DRY AFTER MIDNIGHT. 08 LONG TERM...SUNDAY THROUGH NEXT FRIDAY... BELOW NORMAL TEMPS THROUGH MID-WEEK WITH NORTHWEST FLOW ALOFT BEFORE WARMING TREND LATE WEEK WITH ABOVE NORMAL TEMPS BY NEXT WEEKEND IN TRANSITION TO SOUTHWESTERLY FLOW PATTERN. COUPLE OF BOUTS OF MAINLY LIGHT RAIN DURING THE PERIOD. THE FIRST IS EXPECTED TO BRUSH S/W CWA LATE SUN NGT THROUGH MON... AS CLIPPER SYSTEM IS SHUTTLED DOWN IN NORTHWEST FLOW ALONG LOW-MID LEVEL BAROCLINIC ZONE. WBZ HEIGHTS 3500-4500 FT AGL SUPPORTS ALL LIQUID PTYPE AT SFC DESPITE WHAT MODEL SNOW ACCUMULATION ALGORITHMS DEPICT. THE SECOND BOUT OF LIGHT RAIN EXPECTED TUE WITH NEXT CLIPPER SYSTEM AND ATTENDANT WARM ADVECTION WING. AMOUNTS WITH BOTH SYSTEMS TO BE VERY LIGHT AND MOSTLY TRACE TO AROUND 0.1 INCH. MAINLY DRY MID TO LATE WEEK WITH MODERATING TEMPS AS RIDGING BUILDS ALOFT. PATTERN LOOKS FAVORABLE FOR MODERATE TO LOCALLY HEAVY RAIN EVENT SOMETIME NEXT WEEKEND OR POSSIBLY JUST BEYOND... WITH FAVORABLE HIGH OVER THE MID ATLANTIC AND RESULTANT SOUTHERLY FLOW ON BACKSIDE PUMPING GULF MOISTURE NORTHWARD WELL IN ADVANCE OF EJECTING SOUTHWEST CONUS TROUGH. TEMPS ABOVE TO POSSIBLY MUCH ABOVE NORMAL FRI THROUGH NEXT WEEKEND. 05 && .DVN WATCHES/WARNINGS/ADVISORIES... IA...NONE. IL...NONE. MO...NONE. && $$
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
319 AM CDT SAT NOV 3 2012 .SYNOPSIS... 06Z SFC ANALYSIS HAS A WEAK LOW NEAR KJLN AND ANOTHER NEAR KSPS. DISCONTINUOUS FRONTS CONNECTED THE LOWS. WEAK INVERTED TROFS EXTENDED FROM THE KJLN LOW INTO NORTHEAST MISSOURI AND INTO WESTERN IOWA. DEW POINTS WERE IN THE 40S AND 50S FROM THE SOUTHERN PLAINS INTO THE LOWER MISSISSIPPI VALLEY WITH 20S AND 30S OVER MUCH OF THE MIDWEST. RADAR SHOWED CONVECTION JUST SOUTH OF THE CWFA WITH SPRINKLES INTO THE FAR SOUTHERN PARTS OF THE CWFA. && .SHORT TERM...TODAY AND TONIGHT... BASED ON CURRENT RADAR AND RAP TRENDS...THE SPRINKLES ACROSS THE FAR SOUTHERN CWFA SHOULD EXIT THE AREA BY SUNRISE AS THE LLJ AND THETA E GRADIENT SHIFT EAST OF THE CWFA. IT APPEARS THAT A LONE SHRA RAN ALONG THE SOUTHERN CWFA BORDER WITH HANCOCK AND MCDONOUGH COUNTIES. ALTHOUGH IT WILL TAKE TIME...THE MID LEVEL CLOUDS SHOULD SLOWLY EXIT THE CWFA DURING THE MORNING HOURS ALLOWING FILTERED SUN TO BE SEEN DURING THE DAY. MAX TEMPERATURES SHOULD BE SIMILAR TO OR JUST A BIT WARMER THAN YESTERDAY GIVEN THE WARMER START. QUIET AND DRY CONDITIONS WILL BE SEEN THIS EVENING AS AN UPPER LEVEL DISTURBANCE DROPS SOUTHEAST TOWARD THE AREA. AFTER MIDNIGHT THIS DISTURBANCE MOVES THROUGH THE CWFA WITH 850-700MB CONDENSATION PRESSURE DEFICITS LOWERING BUT THE 1000-850MB CONDENSATION PRESSURE DEFICITS REMAIN HIGH. THERE SHOULD AGAIN BE A MID LEVEL CLOUD DECK MOVING INTO THE AREA. THE THETA E GRADIENT ASSOCIATED WITH THE DISTURBANCE IS WEAK AND VERY DIFFUSE AND THE OVERALL FORCING IS EITHER NOT THERE OR VERY WEAK. SPRINKLES LOOK QUESTIONABLE SO HAVE OPTED TO GO DRY AFTER MIDNIGHT. 08 .LONG TERM...SUNDAY THROUGH NEXT FRIDAY... BELOW NORMAL TEMPS THROUGH MID-WEEK WITH NORTHWEST FLOW ALOFT BEFORE WARMING TREND LATE WEEK WITH ABOVE NORMAL TEMPS BY NEXT WEEKEND IN TRANSITION TO SOUTHWESTERLY FLOW PATTERN. COUPLE OF BOUTS OF MAINLY LIGHT RAIN DURING THE PERIOD. THE FIRST IS EXPECTED TO BRUSH S/W CWA LATE SUN NGT THROUGH MON... AS CLIPPER SYSTEM IS SHUTTLED DOWN IN NORTHWEST FLOW ALONG LOW-MID LEVEL BAROCLINIC ZONE. WBZ HEIGHTS 3500-4500 FT AGL SUPPORTS ALL LIQUID PTYPE AT SFC DESPITE WHAT MODEL SNOW ACCUMULATION ALGORITHMS DEPICT. THE SECOND BOUT OF LIGHT RAIN EXPECTED TUE WITH NEXT CLIPPER SYSTEM AND ATTENDANT WARM ADVECTION WING. AMOUNTS WITH BOTH SYSTEMS TO BE VERY LIGHT AND MOSTLY TRACE TO AROUND 0.1 INCH. MAINLY DRY MID TO LATE WEEK WITH MODERATING TEMPS AS RIDGING BUILDS ALOFT. PATTERN LOOKS FAVORABLE FOR MODERATE TO LOCALLY HEAVY RAIN EVENT SOMETIME NEXT WEEKEND OR POSSIBLY JUST BEYOND... WITH FAVORABLE HIGH OVER THE MID ATLANTIC AND RESULTANT SOUTHERLY FLOW ON BACKSIDE PUMPING GULF MOISTURE NORTHWARD WELL IN ADVANCE OF EJECTING SOUTHWEST CONUS TROUGH. TEMPS ABOVE TO POSSIBLY MUCH ABOVE NORMAL FRI THROUGH NEXT WEEKEND. 05 && .AVIATION... VFR WX IS EXPECTED TO CONTINUE THROUGH 12Z/04. SPRINKLES MAY BE SEEN AT KBRL PRIOR TO SUNRISE SATURDAY AS LOW PRESSURE MOVES ACROSS SOUTHERN MISSOURI. 08 && .DVN WATCHES/WARNINGS/ADVISORIES... IA...NONE. IL...NONE. MO...NONE. && $$ 08/05
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
702 PM EDT SAT NOV 3 2012 .AVIATION... //DISCUSSION... MVFR STRATUS WILL CONTINUE TO ERODE WITH NO MORE THAN A SCATTERED LAYER OF STRATUS BLO 3000 FEET BY 02Z-03Z. THEREAFTER...THICKENING MID LEVEL DECK AROUND 10-15KFT WILL PROGRESS OVER THE AREA WITH AN APPROACHING SHORTWAVE. THIS SHORTWAVE WILL CROSS THE GENERAL AREA ON SUNDAY...BRINGING ADDITIONAL HIGH CEILINGS...BUT DO NOT ANTICIPATE ANYTHING BLO 10KFT ATTM. //DTW THRESHOLD THREATS... * NONE. && .PREV DISCUSSION...ISSUED 337 PM EDT SAT NOV 3 2012 SHORT TERM...THIS EVENING AND TONIGHT A STABLE SURFACE RIDGE WILL MAINTAIN A FIRM GRASP OF SOUTHEASTERN MICHIGAN THROUGHOUT THE NIGHT. NAM AND RAP ARE SHOWING A RIBBON OF VORTICITY ENERGY SHEARING OUT OF THE ND/MN ANOMALY...STRINGING INTO SOUTHERN LOWER MICHIGAN FROM THE WEST. MODEL SOLUTIONS ARE ALSO DEPICTING A WING OF 700-500MB FRONTOGENSIS SLIDING OVER THE CWA. THIS FORCING IS NOW DRIVING THE REFLECTIVITY RETURNS OVER PORTIONS OF SOUTHERN WISCONSIN/ILLINOIS/LAKE MICHIGAN. FORECAST SOUNDINGS SHOW A SATURATED/WEAK LAPSE RATE LAYER BETWEEN 15-20 KFT AGL OVERNIGHT DUE TO THIS FORCING...NECESSITATING AN INCREASED MENTION OF CLOUDS. A DEEP DRY SLAB WILL REMAIN IN PLACE BETWEEN 4-15 KFT AGL...WITH NO REAL SHOT AT ANY PRECIPITATION. THIS IS IN AGREEMENT WITH THE LACK OF SFC HYDROMETEORS BEING REPORTED IN UPSTREAM OBSERVATIONS. GIVEN THE PERSISTENCE OF THE NORTHERLY FLOW TRAJECTORY...WILL BUMP TEMPERATURES UPWARD A DEGREE OR TWO FOR THE FAR EASTERN CWA. TEMPERATURES LAST NIGHT WERE ABLE TO HANG ON FOR A FEW LOCATIONS...MOST NOTABLY THE BULK OF THE THUMB. OTHERWISE...DO NOT WANT TO GET TOO CARRIED AWAY WITH RAISING MINIMUMS...GIVEN THE COLD SURFACE RIDGE AND NOTHING MORE THAN HIGH CLOUD CONCERNS. LONG TERM...SUNDAY THROUGH NEXT SATURDAY A SURFACE RIDGE LOCATED OVER THE WESTERN GREAT LAKES WILL MAINTAIN CONTROL OVER THE WEATHER ACROSS THE REGION THROUGH THE PERIOD AS IT SLOWLY MOVES EAST THROUGH THE GREAT LAKES THROUGH MONDAY. COOL AIR ALOFT COMBINED WITH SINKING MOTION FROM THE HIGH WILL KEEP MIXING HEIGHTS SHALLOW DURING THIS PERIOD...MAINTAINING COLDER THAN NORMAL TEMPERATURES THROUGH EARLY NEXT WEEK. ONE INTERESTING FEATURE THE NWP MODELS CONTINUE TO KEY IN ON IS LAKE EFFECT OVER SOUTHERN LAKE HURON BRINGING LIGHT PRECIPITATION TO THE THUMB REGION SUNDAY THROUGH MONDAY. HOWEVER CLOSER INSPECTION SHOWS A VERY SHALLOW INVERSION LEVEL AROUND 3-4K FEET WITH ABUNDANT DRY AIR ABOVE 850 MB. THE SHALLOW INVERSION HEIGHTS...DRY AIR AND RATHER UNIMPRESSIVE DELTA T VALUES LEND ITSELF TO A CONTINUED DRY FORECAST WITH INCREASED CLOUDINESS OVER THIS AREA BEING THE EXPECTED RESULT OF THE FLOW OFF LAKE HURON DURING THIS PERIOD. AS THE HIGH MOVES OFF TO THE EAST...A TROUGH WILL DIG INTO THE WESTERN GREAT LAKES REGION ON TUESDAY...TRACKING THROUGH THE CENTRAL GREAT LAKES TUESDAY NIGHT AND LIFTING OUT ON WEDNESDAY. THIS SHORTWAVE WILL BE OF PACIFIC ORIGIN...WITH NO WAY TO TAP INTO THE MOISTURE FROM THE LARGE NOREASTER TRACKING ALONG THE ATLANTIC SEABOARD DURING THIS SAME TIME PERIOD. THEREFORE WILL CONTINUE TO MAINTAIN LOW CHANCY POPS DURING THIS PERIOD AS THIS SYSTEM WILL BE SEVERELY MOISTURE STARVED. TEMPERATURES WILL CONTINUE TO BE ON THE COOL SIDE AS THE SYSTEM FAILS TO PULL IN WARMER AIR FROM THE SOUTH INTO THE CENTRAL GREAT LAKES. LARGE SCALE RIDGING WILL DOMINATE THE WEATHER ACROSS THE GREAT LAKES DURING THE LATE PART OF THE WORK WEEK AND INTO EARLY NEXT WEEKEND...KEEPING THE WEATHER DRY. THE RIDGING WILL ALSO PULL IN SOME WARMER AIR FROM THE WEST AS 850 MB TEMPERATURES WARM FROM THE SINGLE DIGITS BELOW ZERO TO THE SINGLE DIGITS ABOVE ZERO AND EVENTUALLY AROUND +10 CELSIUS BY SATURDAY. THIS WILL BRING A GRADUAL WARMUP THROUGH EARLY NEXT WEEKEND AS NEXT SATURDAYS HIGHS ARE FORECAST TO EXCEED NORMAL LEVELS. MARINE... NORTHERLY WINDS WILL DECREASE TO 15 KNOTS OR BELOW BY LATE EVENING...HOWEVER GIVEN THE CONTINUED NORTHERLY DIRECTION...WAVE HEIGHTS WILL BE SLOW TO SUBSIDE. WAVE HEIGHTS LOOK TO FALL BELOW 5 FEET OVERNIGHT. FAIRLY QUIET CONDITIONS ARE THEN EXPECTED LATE SUNDAY THROUGH MONDAY AS THE HIGH SINKS DOWN OVER THE AREA. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LAKE HURON... SMALL CRAFT ADVISORY...LHZ421-LHZ443...UNTIL 10 PM SATURDAY. SMALL CRAFT ADVISORY...NEARSHORE WATERS FROM PORT AUSTIN TO PORT SANILAC...UNTIL 4 AM SUNDAY. LAKE ST CLAIR...NONE. MI WATERS OF LAKE ERIE...NONE. && $$ AVIATION.....DG SHORT TERM...CB LONG TERM....KURIMSKI MARINE.......CB YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
337 PM EDT SAT NOV 3 2012 .SHORT TERM...THIS EVENING AND TONIGHT A STABLE SURFACE RIDGE WILL MAINTAIN A FIRM GRASP OF SOUTHEASTERN MICHIGAN THROUGHOUT THE NIGHT. NAM AND RAP ARE SHOWING A RIBBON OF VORTICITY ENERGY SHEARING OUT OF THE ND/MN ANOMALY...STRINGING INTO SOUTHERN LOWER MICHIGAN FROM THE WEST. MODEL SOLUTIONS ARE ALSO DEPICTING A WING OF 700-500MB FRONTOGENSIS SLIDING OVER THE CWA. THIS FORCING IS NOW DRIVING THE REFLECTIVITY RETURNS OVER PORTIONS OF SOUTHERN WISCONSIN/ILLINOIS/LAKE MICHIGAN. FORECAST SOUNDINGS SHOW A SATURATED/WEAK LAPSE RATE LAYER BETWEEN 15-20 KFT AGL OVERNIGHT DUE TO THIS FORCING...NECESSITATING AN INCREASED MENTION OF CLOUDS. A DEEP DRY SLAB WILL REMAIN IN PLACE BETWEEN 4-15 KFT AGL...WITH NO REAL SHOT AT ANY PRECIPITATION. THIS IS IN AGREEMENT WITH THE LACK OF SFC HYDROMETEORS BEING REPORTED IN UPSTREAM OBSERVATIONS. GIVEN THE PERSISTENCE OF THE NORTHERLY FLOW TRAJECTORY...WILL BUMP TEMPERATURES UPWARD A DEGREE OR TWO FOR THE FAR EASTERN CWA. TEMPERATURES LAST NIGHT WERE ABLE TO HANG ON FOR A FEW LOCATIONS...MOST NOTABLY THE BULK OF THE THUMB. OTHERWISE...DO NOT WANT TO GET TOO CARRIED AWAY WITH RAISING MINIMUMS...GIVEN THE COLD SURFACE RIDGE AND NOTHING MORE THAN HIGH CLOUD CONCERNS. && .LONG TERM...SUNDAY THROUGH NEXT SATURDAY A SURFACE RIDGE LOCATED OVER THE WESTERN GREAT LAKES WILL MAINTAIN CONTROL OVER THE WEATHER ACROSS THE REGION THROUGH THE PERIOD AS IT SLOWLY MOVES EAST THROUGH THE GREAT LAKES THROUGH MONDAY. COOL AIR ALOFT COMBINED WITH SINKING MOTION FROM THE HIGH WILL KEEP MIXING HEIGHTS SHALLOW DURING THIS PERIOD...MAINTAINING COLDER THAN NORMAL TEMPERATURES THROUGH EARLY NEXT WEEK. ONE INTERESTING FEATURE THE NWP MODELS CONTINUE TO KEY IN ON IS LAKE EFFECT OVER SOUTHERN LAKE HURON BRINGING LIGHT PRECIPITATION TO THE THUMB REGION SUNDAY THROUGH MONDAY. HOWEVER CLOSER INSPECTION SHOWS A VERY SHALLOW INVERSION LEVEL AROUND 3-4K FEET WITH ABUNDANT DRY AIR ABOVE 850 MB. THE SHALLOW INVERSION HEIGHTS...DRY AIR AND RATHER UNIMPRESSIVE DELTA T VALUES LEND ITSELF TO A CONTINUED DRY FORECAST WITH INCREASED CLOUDINESS OVER THIS AREA BEING THE EXPECTED RESULT OF THE FLOW OFF LAKE HURON DURING THIS PERIOD. AS THE HIGH MOVES OFF TO THE EAST...A TROUGH WILL DIG INTO THE WESTERN GREAT LAKES REGION ON TUESDAY...TRACKING THROUGH THE CENTRAL GREAT LAKES TUESDAY NIGHT AND LIFTING OUT ON WEDNESDAY. THIS SHORTWAVE WILL BE OF PACIFIC ORIGIN...WITH NO WAY TO TAP INTO THE MOISTURE FROM THE LARGE NOREASTER TRACKING ALONG THE ATLANTIC SEABOARD DURING THIS SAME TIME PERIOD. THEREFORE WILL CONTINUE TO MAINTAIN LOW CHANCY POPS DURING THIS PERIOD AS THIS SYSTEM WILL BE SEVERELY MOISTURE STARVED. TEMPERATURES WILL CONTINUE TO BE ON THE COOL SIDE AS THE SYSTEM FAILS TO PULL IN WARMER AIR FROM THE SOUTH INTO THE CENTRAL GREAT LAKES. LARGE SCALE RIDGING WILL DOMINATE THE WEATHER ACROSS THE GREAT LAKES DURING THE LATE PART OF THE WORK WEEK AND INTO EARLY NEXT WEEKEND...KEEPING THE WEATHER DRY. THE RIDGING WILL ALSO PULL IN SOME WARMER AIR FROM THE WEST AS 850 MB TEMPERATURES WARM FROM THE SINGLE DIGITS BELOW ZERO TO THE SINGLE DIGITS ABOVE ZERO AND EVENTUALLY AROUND +10 CELSIUS BY SATURDAY. THIS WILL BRING A GRADUAL WARMUP THROUGH EARLY NEXT WEEKEND AS NEXT SATURDAYS HIGHS ARE FORECAST TO EXCEED NORMAL LEVELS. && .MARINE... NORTHERLY WINDS WILL DECREASE TO 15 KNOTS OR BELOW BY LATE EVENING...HOWEVER GIVEN THE CONTINUED NORTHERLY DIRECTION...WAVE HEIGHTS WILL BE SLOW TO SUBSIDE. WAVE HEIGHTS LOOK TO FALL BELOW 5 FEET OVERNIGHT. FAIRLY QUIET CONDITIONS ARE THEN EXPECTED LATE SUNDAY THROUGH MONDAY AS THE HIGH SINKS DOWN OVER THE AREA. && .AVIATION...ISSUED 142 PM EDT SAT NOV 3 2012 //DISCUSSION... MVFR STRATUS HAS FILLED BACK IN THIS MORNING WITH THE AID OF DIURNAL HEATING. THE 12Z DTX RAOB AND SATELLITE TRENDS SUPPORT MORE MOISTURE/SATURATION TO CONTEND WITH THAN THE FCST SOUNDINGS HAVE RESOLVED. GIVEN THE COLD NORTHERLY FLOW...WILL TAKE A MORE AGGRESSIVE APPROACH WITH MVFR/VFR CLOUDS THIS AFTERNOON. THE LOWER TROPOSPHERIC CLOUD CANOPY WILL DISSIPATE THIS EVENING. HIGH CLOUDS FROM SOME ENERGY SHEARING INTO LOWER MICHIGAN WILL BRING ADDITIONAL CLOUDINESS AOA 12 KFT AGL FOR THE OVERNIGHT. AT DTW...BEEN WATCHING SATURATION AT 2 KFT AGL OCCUR FROM NORTH TO SOUTH DURING THE LATE MORNING. STILL SOME QUESTION IF LOCAL EFFECTS CAN KEEP THE CLOUDS OUT OF DTW DURING THE AFTERNOON. GIVEN HOW AGGRESSIVE THE CLOUD EXPANSION HAS BEEN WILL BE INTRODUCING AN MVFR CLOUD GROUP FOR STRETCH THIS AFTERNOON. //DTW THRESHOLD THREATS... * LOW CONFIDENCE ON CHANCES AND TIMING OF CEILINGS BELOW 5 KFT THIS AFTERNOON. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LAKE HURON... SMALL CRAFT ADVISORY...LHZ421-LHZ443...UNTIL 10 PM SATURDAY. SMALL CRAFT ADVISORY...NEARSHORE WATERS FROM PORT AUSTIN TO PORT SANILAC...UNTIL 4 AM SUNDAY. LAKE ST CLAIR...NONE. MI WATERS OF LAKE ERIE...NONE. && $$ SHORT TERM...CB LONG TERM....KURIMSKI MARINE.......CB AVIATION.....CB YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1220 PM EDT SAT NOV 3 2012 .SYNOPSIS... ISSUED AT 326 AM EDT SAT NOV 3 2012 HIGH PRESSURE OVER ONTARIO WILL KEEP THINGS DRY AROUND THE GREAT LAKES INTO EARLY NEXT WEEK. TEMPERATURES WILL REMAIN ON THE COOL SIDE WITH HIGHS IN THE MID 40S. A COLD FRONT TUESDAY NIGHT MAY BRING SHOWERS TO THE AREA. && .UPDATE... ISSUED AT 1141 AM EDT SAT NOV 3 2012 UPDATED TO GO WITH MORE IN THE WAY OF CLOUDS THIS AFTERNOON. KAPX AND KDTX MORNING SOUNDINGS SHOW A SUBSIDENCE INVERSION WITH MOISTURE TRAPPED BENEATH IT. THE FLOW IS NORTHERLY...WHICH IS KEEPING THE BULK OF THE LAKE MICHIGAN AND LAKE HURON CLOUDS TO THE WEST AND EAST OF THE AREA. THE ISSUE THOUGH IS THAT MOISTURE HAS STREAMED SOUTH OFF OF SUPERIOR AND THE VERY NORTHERN PORTIONS OF MICHIGAN AND HURON. THIS MOISTURE IS BEING TRAPPED BENEATH THE INVERSION AND NOT ERODING MUCH. IN FACT THERE HAS BEEN A DIURNAL EXPANSION ON THE EDGES. SO...MOSTLY CLOUDY SHOULD COVER THINGS THROUGH THE AFTERNOON. TEMPERATURES WILL ONLY SLOWLY NOSE INTO THE LOWER 40S FOR HIGHS. UPSTREAM RADARS INDICATE LIGHT PRECIPITATION/VIRGA OVER WISCONSIN. VERY FEW IF ANY OB SITES ARE REPORTING PRECIP AT GROUND LEVEL THOUGH. MADISON DID REPORT A FEW FLURRIES AN HOUR AGO. FEEL THAT THE MID LEVELS ARE A BIT TOO DRY TO BRING PRECIP IN SO KEPT THE FORECAST DRY FOR THE AFTERNOON. THE DRY FORECAST IS SUPPORTED BY THE 00Z NSSL WRF. THE HRRR DOES SHOW SOME REFLECTIVITY OVER THE CWA LATE THIS AFTERNOON...BUT THINKING MOST IF NOT ALL OF THIS WILL BE VIRGA. && .SHORT TERM...(TODAY THROUGH MONDAY) ISSUED AT 326 AM EDT SAT NOV 3 2012 FORECAST CONCERNS ARE MINIMAL THIS MORNING AS HIGH PRESSURE OVER ONTARIO WILL RESULT IN DRY WX THROUGH THE SHORT TERM. THE GOING FORECAST LOOKS PRETTY GOOD AND WE ONLY TWEAKED THE GRIDS A LITTLE. LATEST IR LOOP SHOWS QUITE A BIT OF CLOUDS OVER NRN LWR AS WELL AS NW OF THE CWA ACROSS THE LAKE AND WISCONSIN WITH MORE CLOUDS MOVING INTO THE AREA. A SHORT WAVE IS MOVING THROUGH THE REGION AND WILL LIKELY RESULT IN SOME CLOUDS BUT NOT MUCH MORE AS THE LOWER ATM IS QUITE DRY. A FEW FLURRIES ARE BEING REPORTED ACROSS THE FAR NRN CWA WHERE CLOUDS ARE A BIT MORE PREVALENT. GIVEN THAT FLOW WILL BE OFF THE LAKE FOR A FEW MORE HOURS WE ADDED SOME FLURRIES/SPRINKLES TO THE FAR NW THIS MORNING. BY LATE MORNING BOUNDARY LAYER WINDS WILL VEER TO THE NNE AND THE LAKE INFLUENCE WILL END. FAIR SKIES EXPECTED TONIGHT INTO MONDAY. TEMPS WILL FALL INTO THE MID 20S TONIGHT AND SUNDAY NIGHT. .LONG TERM...(MONDAY NIGHT THROUGH FRIDAY) ISSUED AT 326 AM EDT SAT NOV 3 2012 THE LONG TERM PORTION OF THE FORECAST LOOKS PRETTY QUIET WITH GRADUALLY MODERATING TEMPERATURES AND PREDOMINATELY DRY WEATHER. THE COLD FRONT/SHORTWAVE FOR TUESDAY INTO WEDNESDAY DOES NOT LOOK VERY IMPRESSIVE AT ALL... WITH THE LATEST GUIDANCE NOW STRUGGLING TO EVEN SQUEEZE OUT QPF. THE MAIN ATTENTION GRABBER IS THE EXPECTED WARM UP LATE IN THE WEEK AND NEXT WEEKEND. MODELS HAVE BEEN CONSISTENTLY SHOWING A DEEP LONGWAVE TROUGH DEVELOPING OVER THE WRN UNITED STATES... WITH A BUILDING UPR RIDGE DOWNSTREAM EAST OF THE ROCKIES. H8 TEMPS OF 7 TO 10C ARE PROGGED TO PUSH INTO THE REGION NEXT FRIDAY... WITH EVEN WARMER AIR EXPECTED FOR NEXT WEEKEND. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY) ISSUED AT 1220 PM EDT SAT NOV 3 2012 MVFR CIGS WITH CLOUD BASES MAINLY IN THE 1.5 TO 2.5 KFT AGL RANGE WILL LINGER THROUGH THE AFTERNOON AND EARLY EVENING. CLOUDS WILL MOST LIKELY DISSIPATE SOMEWHAT TONIGHT WITH MVFR TO VFR CONDITIONS EXPECTED. FAIRLY EXTENSIVE LOW CLOUD COVER WITH MAINLY MVFR CONDITIONS IS ANTICIPATED SUNDAY MORNING AND EARLY AFTN. && .MARINE... ISSUED AT 326 AM EDT SAT NOV 3 2012 CANCELED THE SCA EARLIER THIS MORNING DUE TO DIMINISHING WINDS AND LOWER WAVES. WINDS/WAVES WILL REMAIN BELOW SCA CRITERIA THIS WEEKEND. && .HYDROLOGY... ISSUED AT 326 AM EDT SAT NOV 3 2012 NO ISSUES THIS MORNING. DRY WX EXPECTED THROUGH MONDAY. LIGHT RAIN IS POSSIBLE TUESDAY NIGHT AHEAD OF THE NEXT FRONTAL BOUNDARY. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...NONE. LM...NONE. && $$ UPDATE...DUKE SYNOPSIS...93 SHORT TERM...93 LONG TERM...MEADE AVIATION...LAURENS HYDROLOGY...93 MARINE...93
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1141 AM EDT SAT NOV 3 2012 .SYNOPSIS... ISSUED AT 326 AM EDT SAT NOV 3 2012 HIGH PRESSURE OVER ONTARIO WILL KEEP THINGS DRY AROUND THE GREAT LAKES INTO EARLY NEXT WEEK. TEMPERATURES WILL REMAIN ON THE COOL SIDE WITH HIGHS IN THE MID 40S. A COLD FRONT TUESDAY NIGHT MAY BRING SHOWERS TO THE AREA. && .UPDATE... ISSUED AT 1141 AM EDT SAT NOV 3 2012 UPDATED TO GO WITH MORE IN THE WAY OF CLOUDS THIS AFTERNOON. KAPX AND KDTX MORNING SOUNDINGS SHOW A SUBSIDENCE INVERSION WITH MOISTURE TRAPPED BENEATH IT. THE FLOW IS NORTHERLY...WHICH IS KEEPING THE BULK OF THE LAKE MICHIGAN AND LAKE HURON CLOUDS TO THE WEST AND EAST OF THE AREA. THE ISSUE THOUGH IS THAT MOISTURE HAS STREAMED SOUTH OFF OF SUPERIOR AND THE VERY NORTHERN PORTIONS OF MICHIGAN AND HURON. THIS MOISTURE IS BEING TRAPPED BENEATH THE INVERSION AND NOT ERODING MUCH. IN FACT THERE HAS BEEN A DIURNAL EXPANSION ON THE EDGES. SO...MOSTLY CLOUDY SHOULD COVER THINGS THROUGH THE AFTERNOON. TEMPERATURES WILL ONLY SLOWLY NOSE INTO THE LOWER 40S FOR HIGHS. UPSTREAM RADARS INDICATE LIGHT PRECIPITATION/VIRGA OVER WISCONSIN. VERY FEW IF ANY OB SITES ARE REPORTING PRECIP AT GROUND LEVEL THOUGH. MADISON DID REPORT A FEW FLURRIES AN HOUR AGO. FEEL THAT THE MID LEVELS ARE A BIT TOO DRY TO BRING PRECIP IN SO KEPT THE FORECAST DRY FOR THE AFTERNOON. THE DRY FORECAST IS SUPPORTED BY THE 00Z NSSL WRF. THE HRRR DOES SHOW SOME REFLECTIVITY OVER THE CWA LATE THIS AFTERNOON...BUT THINKING MOST IF NOT ALL OF THIS WILL BE VIRGA. && .SHORT TERM...(TODAY THROUGH MONDAY) ISSUED AT 326 AM EDT SAT NOV 3 2012 FORECAST CONCERNS ARE MINIMAL THIS MORNING AS HIGH PRESSURE OVER ONTARIO WILL RESULT IN DRY WX THROUGH THE SHORT TERM. THE GOING FORECAST LOOKS PRETTY GOOD AND WE ONLY TWEAKED THE GRIDS A LITTLE. LATEST IR LOOP SHOWS QUITE A BIT OF CLOUDS OVER NRN LWR AS WELL AS NW OF THE CWA ACROSS THE LAKE AND WISCONSIN WITH MORE CLOUDS MOVING INTO THE AREA. A SHORT WAVE IS MOVING THROUGH THE REGION AND WILL LIKELY RESULT IN SOME CLOUDS BUT NOT MUCH MORE AS THE LOWER ATM IS QUITE DRY. A FEW FLURRIES ARE BEING REPORTED ACROSS THE FAR NRN CWA WHERE CLOUDS ARE A BIT MORE PREVALENT. GIVEN THAT FLOW WILL BE OFF THE LAKE FOR A FEW MORE HOURS WE ADDED SOME FLURRIES/SPRINKLES TO THE FAR NW THIS MORNING. BY LATE MORNING BOUNDARY LAYER WINDS WILL VEER TO THE NNE AND THE LAKE INFLUENCE WILL END. FAIR SKIES EXPECTED TONIGHT INTO MONDAY. TEMPS WILL FALL INTO THE MID 20S TONIGHT AND SUNDAY NIGHT. .LONG TERM...(MONDAY NIGHT THROUGH FRIDAY) ISSUED AT 326 AM EDT SAT NOV 3 2012 THE LONG TERM PORTION OF THE FORECAST LOOKS PRETTY QUIET WITH GRADUALLY MODERATING TEMPERATURES AND PREDOMINATELY DRY WEATHER. THE COLD FRONT/SHORTWAVE FOR TUESDAY INTO WEDNESDAY DOES NOT LOOK VERY IMPRESSIVE AT ALL... WITH THE LATEST GUIDANCE NOW STRUGGLING TO EVEN SQUEEZE OUT QPF. THE MAIN ATTENTION GRABBER IS THE EXPECTED WARM UP LATE IN THE WEEK AND NEXT WEEKEND. MODELS HAVE BEEN CONSISTENTLY SHOWING A DEEP LONGWAVE TROUGH DEVELOPING OVER THE WRN UNITED STATES... WITH A BUILDING UPR RIDGE DOWNSTREAM EAST OF THE ROCKIES. H8 TEMPS OF 7 TO 10C ARE PROGGED TO PUSH INTO THE REGION NEXT FRIDAY... WITH EVEN WARMER AIR EXPECTED FOR NEXT WEEKEND. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 749 AM EDT SAT NOV 3 2012 NUMEROUS MVFR CIGS WERE NOTED OVER WRN AND NRN LWR MI EARLY THIS MORNING. THESE CLOUDS ARE EXPECTED TO BECOME SCATTERED BY NOON LEAVING PREDOMINATELY VFR CONDITIONS FOR THE REST OF TODAY AND TONIGHT. SOME CLOUDS WITH BASES AOA 12K FT WILL ALSO IMPACT THE REGION LATER TODAY AND TONIGHT. && .MARINE... ISSUED AT 326 AM EDT SAT NOV 3 2012 CANCELED THE SCA EARLIER THIS MORNING DUE TO DIMINISHING WINDS AND LOWER WAVES. WINDS/WAVES WILL REMAIN BELOW SCA CRITERIA THIS WEEKEND. && .HYDROLOGY... ISSUED AT 326 AM EDT SAT NOV 3 2012 NO ISSUES THIS MORNING. DRY WX EXPECTED THROUGH MONDAY. LIGHT RAIN IS POSSIBLE TUESDAY NIGHT AHEAD OF THE NEXT FRONTAL BOUNDARY. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...NONE. LM...NONE. && $$ UPDATE...DUKE SYNOPSIS...93 SHORT TERM...93 LONG TERM...MEADE AVIATION...MEADE HYDROLOGY...93 MARINE...93
AREA FORECAST DISCUSSION...UPDATED
NWS ST LOUIS MO
934 PM CST SUN NOV 4 2012 .UPDATE... ISSUED AT 933 PM CST SUN NOV 4 2012 INHERITED FCST STILL LOOKS GOOD...SO NO MAJOR CHANGES THIS EVENING. LGHT RAIN/SPRINKLES HAVE BEEN OCCURRING THIS EVENING...MOSTLY ACROSS OUR IL COUNTIES. STILL WAITING ON THE POTENT UPPER LEVEL SYSTEM COMING OUT OF THE PLAINS THIS EVENING. THE ATMOSPHERE IS SATURATING AS THE SHORT WAVE MOVES SSE OUT OF ERN NEBRASKA AND INTERACTS WITH THE SFC LOW OVER WRN IA. MODELS IN GOOD AGREEMENT THAT THE SHORT WAVE WILL STRENGTHEN AS IT DIVES THRU WRN MO OVERNIGHT AND MONDAY MORNING. MOST OF THE ECHOS ACROSS IA AND NW MO ARE VERY LIGHT ATTM BUT THE INTENSITY SHOULD INCREASE AS THE SHORT WAVE GETS CLOSER. MONDAY WILL BE A CHILLY DAMP DAY WITH PRECIP ENDING FROM N-S. NOT MUCH RISE ON TEMPS EXPECTED EITHER WITH AN ERLY WIND AND PLENTY OF CLOUDS. MILLER MILLER && .SHORT TERM... ISSUED AT 233 PM CST SUN NOV 4 2012 (TONIGHT) POTENT LITTLE SHORTWAVE IS DEVELOPING OVER NORTHEAST MONTANA...AND WILL DIVE SOUTHEAST THROUGH THE GREAT PLAINS TONIGHT. THE SURFACE REFLECTION OF THIS WAVE WILL LIKEWISE DROP SOUTHEAST INTO THE PLAINS AND LINK UP WITH A BROAD/RELATIVELY WEAK AREA OF LOW PRESSURE CURRENTLY SITTING OVER KANSAS. THE COMBINED SURFACE TROF WILL STRENGTHEN SLIGHTLY AS IT MOVES INTO NORTHWEST MISSOURI LATE TONIGHT. MODELS ARE IN GOOD AGREEMENT IN SPREADING A SWATH OF RAIN OUT SOUTHEAST AHEAD OF THE SHORTWAVE. THE ONSET OF PRECIP LOOKS FASTER THAN PREVIOUSLY THOUGHT...THE HRRR IS ESPECIALLY FAST BRINGING PRECIP INTO CENTRAL MO AS EARLY AS 03Z...AND SPREADING TO NEAR THE MISSISSIPPI RIVER BY 06Z. AM STICKING CLOSER TO THE OPERATIONAL NAM AND GFS SOLUTIONS WHICH ARE 3-6HRS SLOWER...BUT WILL BRIEF THE EVENING SHIFT TO WATCH FOR A FASTER ONSET OF RAIN. CARNEY && .LONG TERM... ISSUED AT 233 PM CST SUN NOV 4 2012 (MONDAY THROUGH SUNDAY) NORTHWEST FLOW ALIVE AND WELL ACROSS THE CENTER OF THE NATION AS A DEEP LONGWAVE TROF CONTINUES TO BE CARVED OUT ACROSS THE EASTERN CONUS. SHORTWAVE OF INTEREST IN THE SHORT TERM WILL CONTINUE TO DIVE SOUTHEAST INTO THE BASE OF THIS LONGWAVE TROF AND BE RESPONSIBLE FOR THE DEVELOPMENT OF A POWERFUL STORM SYSTEM THAT WILL MOVE UP THE EAST COAST DURING THE MIDDLE PORTION OF THIS WEEK. THIS WILL CERTAINLY BE THE NATIONS WEATHER STORY...AS THE NOR`EASTER BRINGS STRONG WIND...RAIN...AND EVEN SOME WINTER WEATHER TO AREAS STILL REELING FROM SANDY. MONDAY AND MONDAY NIGHT... MODEL GUIDANCE IN VERY GOOD AGREEMENT REGARDING THE TRACK OF THE SHORTWAVE ACROSS MISSOURI. AREA OF LIGHT RAIN WILL WORK ITS WAY SOUTH ACROSS THE REGION WITH THICK CLOUD COVER AND CHILLY TEMPERATURES. HAVE WENT A DEGREE OR TWO BELOW THE LOWEST MODEL GUIDANCE. RAIN SHOULD PUSH SOUTH OF THE AREA BY MONDAY NIGHT...BUT CLOUDS WILL HANG TOUGH IN THE WAKE OF THIS SYSTEM. HAVE KEPT TEMPERATURES WARMER THAN GUIDANCE WOULD SUGGEST...WITH A LIMITED DIURNAL TEMPERATURE SWING. TUESDAY AND WEDNESDAY... A FINAL SHORTWAVE...THE CABOOSE...WILL TRACK ACROSS THE WESTERN GREAT LAKES...PUSHING A FINAL COLD FRONT ACROSS THE AREA. LIMITED MOISTURE AND AN EASTERN TRACK TO THE DISTURBANCE KEEPS POPS AT SLIGHT CHANCE AND CONFINED TO ILLINOIS COUNTIES. SURFACE RIDGE OF HIGH PRESSURE WILL THEN BUILD ACROSS THE CWA ON WEDNESDAY WITH DRY WEATHER AND SEASONAL TEMPERATURES. THURSDAY THROUGH SUNDAY... THE UPPER AIR PATTERN WILL FINALLY TRANSITION BY WEEKS END AS A MASSIVE STORM SYSTEM CARVES A LONGWAVE TROF ACROSS THE WESTERN CONUS WHICH HELPS AMPLIFY A RIDGE DOWNSTREAM ACROSS THE EASTERN CONUS. THE END RESULT WILL BE SOUTHWEST FLOW ACROSS THE MIDWEST AND ABOVE NORMAL TEMPERATURES. THIS LARGE UPPER TROF WILL BE PROGRESSIVE WITH RAIN CHANCES INCREASING SUNDAY AND SUNDAY NIGHT. CVKING && .AVIATION... ISSUED AT 537 PM CST SUN NOV 4 2012 AN UPPER LEVEL TROUGH AND ASSOCIATED WEAK SFC LOW WILL DROP S-SEWD THROUGH WRN MO LATE TGT AND MON MRNG. MID LEVEL CLOUDS HAVE ALREADY SPREAD SEWD INTO OUR AREA EARLY THIS EVNG ALONG WITH A FEW SPRINKLES. THE CLOUD COVER WILL LOWER AND THICKEN THIS EVNG INTO THE OVERNIGHT HOURS WITH CIGS DROPPING INTO THE MVFR CATAGORY LATE TGT IN UIN AND COU AND IN THE ST LOUIS METRO AREA EARLY MON MRNG. THE CIGS MAY BRIEFLY DROP INTO THE IFR CATAGORY ON MON. SIGNIFICANT RAIN WILL ALSO SPREAD SEWD INTO UIN AND COU LATE TGT AND INTO THE ST LOUIS METRO AREA EARLY MON MRNG WITH VSBYS FALLING TO 5-6SM. A SELY SFC WIND WILL BACK AROUND TO AN ELY DIRECTION MON AFTN AS THE WEAK SFC LOW SHIFTS SW OF THE AREA. SPECIFICS FOR KSTL...THE CLOUD CEILING WILL GRADUALLY LOWER THROUGH THE NIGHT...INTO THE MVFR CATAGORY BY EARLY MON MRNG AS LIGHT RAIN MOVES INTO THE AREA. THERE MAY BE SPRINKLES TGT BUT SIGNIFICANT RAIN DROPPING VSBYS TO 5-6SM SHOULD NOT OCCUR UNTIL EARLY MON MRNG. THE RAIN WILL SHIFT SE OF STL BY EARLY MON EVNG ALTHOUGH MVFR CIGS WILL CONTINUE. A LIGHT ELY SFC WIND WILL VEER AROUND TO A SELY DIRECTION THIS EVNG...AND INCREASE TO 8-9 KTS MON MRNG. THE SFC WIND WILL BACK AROUND TO AN ELY DIRECTION BY EARLY MON EVNG AS IT BECOMES LIGHT AGAIN. GKS && .LSX WATCHES/WARNINGS/ADVISORIES... MO...NONE. IL...NONE. && $$ WFO LSX
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
613 PM CST SUN NOV 4 2012 .SHORT TERM... ISSUED AT 233 PM CST SUN NOV 4 2012 (TONIGHT) POTENT LITTLE SHORTWAVE IS DEVELOPING OVER NORTHEAST MONTANA...AND WILL DIVE SOUTHEAST THROUGH THE GREAT PLAINS TONIGHT. THE SURFACE REFLECTION OF THIS WAVE WILL LIKEWISE DROP SOUTHEAST INTO THE PLAINS AND LINK UP WITH A BROAD/RELATIVELY WEAK AREA OF LOW PRESSURE CURRENTLY SITTING OVER KANSAS. THE COMBINED SURFACE TROF WILL STRENGTHEN SLIGHTLY AS IT MOVES INTO NORTHWEST MISSOURI LATE TONIGHT. MODELS ARE IN GOOD AGREEMENT IN SPREADING A SWATH OF RAIN OUT SOUTHEAST AHEAD OF THE SHORTWAVE. THE ONSET OF PRECIP LOOKS FASTER THAN PREVIOUSLY THOUGHT...THE HRRR IS ESPECIALLY FAST BRINGING PRECIP INTO CENTRAL MO AS EARLY AS 03Z...AND SPREADING TO NEAR THE MISSISSIPPI RIVER BY 06Z. AM STICKING CLOSER TO THE OPERATIONAL NAM AND GFS SOLUTIONS WHICH ARE 3-6HRS SLOWER...BUT WILL BRIEF THE EVENING SHIFT TO WATCH FOR A FASTER ONSET OF RAIN. CARNEY && .LONG TERM... ISSUED AT 233 PM CST SUN NOV 4 2012 (MONDAY THROUGH SUNDAY) NORTHWEST FLOW ALIVE AND WELL ACROSS THE CENTER OF THE NATION AS A DEEP LONGWAVE TROF CONTINUES TO BE CARVED OUT ACROSS THE EASTERN CONUS. SHORTWAVE OF INTEREST IN THE SHORT TERM WILL CONTINUE TO DIVE SOUTHEAST INTO THE BASE OF THIS LONGWAVE TROF AND BE RESPONSIBLE FOR THE DEVELOPMENT OF A POWERFUL STORM SYSTEM THAT WILL MOVE UP THE EAST COAST DURING THE MIDDLE PORTION OF THIS WEEK. THIS WILL CERTAINLY BE THE NATIONS WEATHER STORY...AS THE NOR`EASTER BRINGS STRONG WIND...RAIN...AND EVEN SOME WINTER WEATHER TO AREAS STILL REELING FROM SANDY. MONDAY AND MONDAY NIGHT... MODEL GUIDANCE IN VERY GOOD AGREEMENT REGARDING THE TRACK OF THE SHORTWAVE ACROSS MISSOURI. AREA OF LIGHT RAIN WILL WORK ITS WAY SOUTH ACROSS THE REGION WITH THICK CLOUD COVER AND CHILLY TEMPERATURES. HAVE WENT A DEGREE OR TWO BELOW THE LOWEST MODEL GUIDANCE. RAIN SHOULD PUSH SOUTH OF THE AREA BY MONDAY NIGHT...BUT CLOUDS WILL HANG TOUGH IN THE WAKE OF THIS SYSTEM. HAVE KEPT TEMPERATURES WARMER THAN GUIDANCE WOULD SUGGEST...WITH A LIMITED DIURNAL TEMPERATURE SWING. TUESDAY AND WEDNESDAY... A FINAL SHORTWAVE...THE CABOOSE...WILL TRACK ACROSS THE WESTERN GREAT LAKES...PUSHING A FINAL COLD FRONT ACROSS THE AREA. LIMITED MOISTURE AND AN EASTERN TRACK TO THE DISTURBANCE KEEPS POPS AT SLIGHT CHANCE AND CONFINED TO ILLINOIS COUNTIES. SURFACE RIDGE OF HIGH PRESSURE WILL THEN BUILD ACROSS THE CWA ON WEDNESDAY WITH DRY WEATHER AND SEASONAL TEMPERATURES. THURSDAY THROUGH SUNDAY... THE UPPER AIR PATTERN WILL FINALLY TRANSITION BY WEEKS END AS A MASSIVE STORM SYSTEM CARVES A LONGWAVE TROF ACROSS THE WESTERN CONUS WHICH HELPS AMPLIFY A RIDGE DOWNSTREAM ACROSS THE EASTERN CONUS. THE END RESULT WILL BE SOUTHWEST FLOW ACROSS THE MIDWEST AND ABOVE NORMAL TEMPERATURES. THIS LARGE UPPER TROF WILL BE PROGRESSIVE WITH RAIN CHANCES INCREASING SUNDAY AND SUNDAY NIGHT. CVKING && .AVIATION... ISSUED AT 537 PM CST SUN NOV 4 2012 AN UPPER LEVEL TROUGH AND ASSOCIATED WEAK SFC LOW WILL DROP S-SEWD THROUGH WRN MO LATE TGT AND MON MRNG. MID LEVEL CLOUDS HAVE ALREADY SPREAD SEWD INTO OUR AREA EARLY THIS EVNG ALONG WITH A FEW SPRINKLES. THE CLOUD COVER WILL LOWER AND THICKEN THIS EVNG INTO THE OVERNIGHT HOURS WITH CIGS DROPPING INTO THE MVFR CATAGORY LATE TGT IN UIN AND COU AND IN THE ST LOUIS METRO AREA EARLY MON MRNG. THE CIGS MAY BRIEFLY DROP INTO THE IFR CATAGORY ON MON. SIGNIFICANT RAIN WILL ALSO SPREAD SEWD INTO UIN AND COU LATE TGT AND INTO THE ST LOUIS METRO AREA EARLY MON MRNG WITH VSBYS FALLING TO 5-6SM. A SELY SFC WIND WILL BACK AROUND TO AN ELY DIRECTION MON AFTN AS THE WEAK SFC LOW SHIFTS SW OF THE AREA. SPECIFICS FOR KSTL...THE CLOUD CEILING WILL GRADUALLY LOWER THROUGH THE NIGHT...INTO THE MVFR CATAGORY BY EARLY MON MRNG AS LIGHT RAIN MOVES INTO THE AREA. THERE MAY BE SPRINKLES TGT BUT SIGNIFICANT RAIN DROPPING VSBYS TO 5-6SM SHOULD NOT OCCUR UNTIL EARLY MON MRNG. THE RAIN WILL SHIFT SE OF STL BY EARLY MON EVNG ALTHOUGH MVFR CIGS WILL CONTINUE. A LIGHT ELY SFC WIND WILL VEER AROUND TO A SELY DIRECTION THIS EVNG...AND INCREASE TO 8-9 KTS MON MRNG. THE SFC WIND WILL BACK AROUND TO AN ELY DIRECTION BY EARLY MON EVNG AS IT BECOMES LIGHT AGAIN. GKS && .LSX WATCHES/WARNINGS/ADVISORIES... MO...NONE. IL...NONE. && $$ WFO LSX
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
105 AM CDT SAT NOV 3 2012 .AVIATION... VFR CONDITIONS FOR KLBF WILL PERSIST THROUGH ENTIRE 06Z TAF PERIOD. ONLY CONCERN FOR KVTN IS THE POSSIBILITY FOR IFR CEILINGS AFTER 10Z. UPSTREAM STRATUS IN SOUTH DAKOTA CONTINUES TO WORK SOUTHEAST TO NEAR PHP. THE LATEST RAP MODEL AND TO A LESSER EXTENT THE NAM12 INDICATE POTENTIAL. HAVE INTRODUCED A SCT009 CLOUD HEIGHT FROM 10Z-18Z. THIS WILL NEED TO BE MONITORED CLOSELY THE NEXT SEVERAL HOURS. OTHERWISE EXPECT FEW TO SCATTERED HIGH CLOUDS OVERNIGHT THROUGH SATURDAY MORNING WITH LIGHT AND VARIABLE WINDS. AFTER 18Z...FEW TO SCT080 WITH SCT TO BKN250. WINDS TO REMAIN LIGHT AT OR BELOW 6KT. HAVE ADDED SOME MIST FOG AND SOME BR TO TAFS WITH DEVELOPING SCENARIO OVER WESTERN NEBRASKA. && .PREV DISCUSSION... /ISSUED 608 PM CDT FRI NOV 2 2012/ AVIATION... VFR CONDITIONS FOR KLBF AND KVTN WILL PERSIST THROUGH ENTIRE 00Z TAF PERIOD. EXPECT FEW TO SCATTERED HIGH CLOUDS OVERNIGHT THROUGH SATURDAY MORNING WITH LIGHT AND VARIABLE WINDS. AFTER 18Z...FEW TO SCT080 WITH SCT TO BKN250. WINDS TO REMAIN LIGHT AT OR BELOW 6KT. PREV DISCUSSION... /ISSUED 302 PM CDT FRI NOV 2 2012/ SHORT TERM...THROUGH 12Z SUNDAY. HIGH PRESSURE WILL BUILD INTO WESTERN AND NORTH CENTRAL NEBRASKA TONIGHT...WITH WINDS DIMINISHING. SKIES WILL EVENTUALLY BECOME AT LEAST PARTLY CLOUDY ACROSS NORTH CENTRAL NEBRASKA...WITH MOSTLY CLEAR TO PARTLY CLOUDY SKIES ACROSS WESTERN AND SOUTHWEST NEBRASKA. WITH THE LIGHT WEST WINDS AND AT LEAST PARTIALLY CLEAR SKIES...HAVE WENT FAIRLY COLD /UPPER 20S/ IN THE TYPICAL COLD SPOTS LIKE THE PLATTE RIVER VALLEY. SATURDAY IS SHAPING UP TO BE A NICE DAY...WITH LIGHT WINDS AND HIGHS IN THE MID 50S TO LOWER 60S. THERE WILL BE SOME HIGH CIRRUS CLOUDS AROUND...ESPECIALLY DURING THE AFTERNOON. LONG TERM...12Z SUNDAY AND BEYOND. UPPER WAVE WILL QUICKLY DROP SOUTHEAST THROUGH THE NORTHERN AND CENTRAL HIGH PLAINS ON SUNDAY BRINGING THE BEST SHOT OF PRECIPITATION...ALBEIT LIGHT...FOR THE NEXT SEVEN DAYS. THE HIGHEST PROBABILITY OF PRECIPITATION APPEARS TO BE TIED TO EASTERN PORTIONS OF SOUTH DAKOTA AND NEBRASKA...IN AN AREA OF FAVORED LIFT SEEN FROM MODEL GENERATED Q-VECTOR FIELDS. WHILE THE STRONGEST LIFT WILL BE EAST AND NORTH OF THE CWA...THE GFS AND EC DO GENERATE SOME LIGHT QPF AS INCREASING JET ENERGY ALOFT PASSES THROUGH THE STATE. THE GFS CONTINUES TO WAFFLE ON THE PLACEMENT OF THE UPPER FEATURES...BUT WITH THE 12Z RUN HAS COME INTO BETTER AGREEMENT WITH THE EC MODELING CAMP WHICH FAVORS A SLIGHTLY STRONGER AND MORE PROGRESSIVE SYSTEM. THIS PATTERN PLACES THE FAVORED LFQ OF THE UPPER JET ACROSS NORTH CENTRAL NEBRASKA. NOW THE NAM IS SOMEWHAT BROAD AND LESS AGGRESSIVE WITH THE MODEL GENERATED QPF. REGARDLESS...MOISTURE PROFILES ARE NOT ALL THAT SUPPORTIVE OF MEASURABLE QPF...SAVE FOR OUR FAR NORTH CENTRAL ZONES. SO WILL MAKE NO WHOLESALE CHANGES TO THE INHERITED POPS SUNDAY AFTERNOON AND EVENING...LEAVING ONLY SLIGHT CHANCE MENTION OVER OUR FAR NORTH CENTRAL ZONES...WHERE PREVIOUSLY INTRODUCED. OTHERWISE...WINDS MAY BECOME BRISK ACROSS THE HIGHER TERRAIN OF THE EASTERN PANHANDLE AND POSSIBLY LOCATIONS ALONG AND SOUTH OF INTERSTATE 80 SUNDAY AFTERNOON. NOT LOOKING AT ANY WIND HEADLINES...BUT INCREASING MOMENTUM ALOFT IS SHOWN TO BE TRANSFERRED DOWN TO THE SURFACE /PER BUFR POINT SOUNDINGS/ AS MIXING COMMENCES ABOVE 750MB...A FEW GUSTS ABOVE 25 MPH MAY BE POSSIBLE. CONFIDENCE IN THE AMOUNT OF EVENTUAL MIXING IS FAIRLY LOW...SO WILL ONLY TREND WINDS SLIGHTLY UPWARD AT THIS POINT IN TIME. HEIGHTS RISE EARLY NEXT WEEK AS THE UPPER WAVE DEEPENS WITHIN A LARGE TROUGH OVER THE SOUTHEASTERN STATES. TEMPERATURES ALOFT WARM IN ADVANCE OF WEAK WAVES/FRONTAL CONVERGENT PERIODS...ALLOWING FOR SEVERAL PLEASANT DAYS MIDWEEK. HIGHS SHOULD REMAIN IN THE 60S...WITH UPPER 50S POSSIBLE ACROSS NORTH CENTRAL NEBRASKA...AND POSSIBLY A 70 DEGREE READING OR TWO ACROSS THE SOUTHWEST WEDNESDAY. THEREAFTER...PRETTY STRONG AGREEMENT THAT A DEEP TROUGH WILL DIG INTO THE WESTERN UNITED STATES...WITH THE UPPER PATTERN OVER THE CENTRAL/NORTHERN PLAINS TRANSITIONING FROM NORTHERLY TO SOUTHWESTERLY. THE EXPECTED UPPER PATTERN AS GIVEN BY THE 02.12Z MODEL RUN IS NOT ALL THAT PROMISING FOR PRECIPITATION FOR WESTERN AND NORTH CENTRAL NEBRASKA...SO UNFORTUNATELY WILL LEAVE THE FORECAST DRY. && .LBF WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SHORT TERM/EXTENDED...JACOBS AVIATION...POWER
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1223 AM CDT SAT NOV 3 2012 .AVIATION...06Z TAF. THE NARROW BAND OF STRATUS THAT HAS BEEN JUST TO THE WEST OF THE KGRI TERMINAL AREA IS STARTING TO DISSIPATE ON THE SOUTHERN END OF THE AREA. WILL KEEP THE KGRI TERMINAL WITH HIGH CLOUDS BUT WILL HAVE TO WAIT TO SEE IF THE STRATUS REDEVELOPS AND MOVES INTO THE TERMINAL. OTHERWISE VFR CONDITIONS ARE EXPECTED WITH FAIRLY LIGHT WINDS. && .PREV DISCUSSION... /ISSUED 250 PM CDT FRI NOV 2 2012/ SHORT TERM...THROUGH 00Z SUNDAY. MORNING UPPER AIR ANALYSIS INDICATES LONG WAVE TROUGHING OVER THE EASTERN ONE-THIRD OF THE CONUS...AND A RIDGE AXIS EXTENDING FROM NEW MEXICO INTO THE NORTHERN PLAINS. TWO MID LEVEL SHORTWAVES...ONE OVER THE NORTHERN PLAINS AND THE OTHER OVER THE SOUTHWESTERN CONUS...ARE ALSO NOTED...WITH ZONAL MID AND UPPER LEVEL FLOW PERSISTING ACROSS THE CENTRAL PLAINS. MID AND UPPER LEVEL JET ENERGY EXTENDS FROM WYOMING...EAST/NORTHEAST ACROSS THE NORTHERN PLAINS AND THEN SOUTHEAST ACROSS THE MISSISSIPPI VALLEY ON INTO THE MID-ATLANTIC. TROPOSPHERIC FLOW REMAINS FAIRLY WEAK OVER OUR AREA AS A RESULT...MAXING OUT AT AROUND 70KTS NEAR 200MB PER 12Z SOUNDING DATA FROM KLBF. WATER VAPOR IMAGERY INDICATES INCREASED VALUES OF MID LEVEL MOISTURE AHEAD OF THE MID LEVEL SHORT WAVE OVER THE SOUTHWESTERN CONUS...WITH THIS INCREASED MID LEVEL MOISTURE EXTENDING FROM THE FOUR-CORNERS REGION...EAST/NORTHEAST ACROSS THE CENTRAL ROCKY MOUNTAIN RANGE AND ON INTO THE CENTRAL PLAINS. PLENTY OF MID AND HIGH LEVEL CLOUDS ARE NOTED INFILTRATING THE CENTRAL PLAINS AS A RESULT. AT THE SURFACE A WEAK AREA OF LOW PRESSURE EXISTS OVER SOUTH CENTRAL KANSAS...WITH A WEAK FRONTAL BOUNDARY EXTENDING EAST/NORTHEAST FROM THE LOW ACROSS PORTIONS OF CENTRAL AND EASTERN KANSAS. AN INVERTED TROUGH IS ALSO NOTED EXTENDING NORTH FROM THE SURFACE LOW INTO NORTH CENTRAL KANSAS AND SOUTH CENTRAL NEBRASKA. THE LOW LEVEL WIND FIELD ACROSS OUR CWA REMAINS SPLIT AS A RESULT...WITH AN EAST/SOUTHEAST WIND ACROSS THE SOUTHEASTERN HALF OF THE CWA...AND A NORTH/NORTHWEST WIND FARTHER NORTHWEST. LOW LEVEL THERMAL ADVECTION ACROSS THE LOW LEVEL BAROCLINIC ZONE...CURRENTLY OVER PORTIONS OF CENTRAL AND EASTERN KANSAS...IS PROMOTING ISENTROPIC UPGLIDE AND SATURATION ALONG THE 290-300K SURFACES...PER RAP ANALYSIS DATA. THIS SATURATION HAS RESULTED IN STRATUS ACROSS NORTHWESTERN PORTIONS OF THE CWA THIS AFTERNOON...WHERE CEILINGS IN THE 1000-2000FT AGL PERSIST. GUIDANCE FROM THE NAM...OPERATIONAL GFS AND EC ALL SUGGEST THE MID LEVEL SHORT WAVE OVER THE NORTHERN PLAINS WILL CONTINUE MOVING EAST/SOUTHEAST THROUGH THE NEXT 24 HOURS. ANY DPVA AND MID LEVEL THERMAL ADVECTION IN ASSOCIATION WITH THIS SYSTEM SHOULD REMAIN WELL NORTH/NORTHEAST OF OUR AREA. IN ADDITION...THE MID LEVEL SHORT WAVE CURRENTLY OVER THE SOUTHWESTERN CONUS IS EXPECTED TO WEAKEN THROUGH THE NEXT 24 HOURS...THUS PRESENTING LITTLE IF ANY OMEGA TO OUR AREA ONCE IT NEARS THE REGION. GIVEN THE OVERALL LACK IN KINEMATIC FORCING OVER OUR AREA THROUGH THE NEXT 24 HOURS...OPTED TO KEEP THE FORECAST DRY FOR TONIGHT AND TOMORROW. GUIDANCE ALSO SUGGESTS THE SURFACE HIGH...CURRENTLY OVER SOUTH CENTRAL KANSAS...WILL PUSH OFF TO THE EAST/SOUTHEAST TONIGHT...THUS ALLOWING WEAK SURFACE RIDGING INTO OUR AREA OVERNIGHT TONIGHT INTO SATURDAY MORNING. ISENTROPIC UPGLIDE SHOULD DISSIPATE ACROSS OUR AREA LATER TONIGHT AS THE LOW LEVEL BAROCLINIC ZONE OVER CENTRAL AND EASTERN PORTIONS OF KANSAS PUSHES OFF TO THE EAST/SOUTHEAST ALONG WITH THE SURFACE LOW. THIS SHOULD BRING AN END TO THE STRATUS CURRENTLY OVER NORTHWESTERN PORTIONS OF OUR CWA. ALSO...THE INCREASED MID LEVEL MOISTURE...BEING USHERED INTO OUR AREA FROM THE SOUTHWEST BY THE SOUTHWESTERN CONUS MID LEVEL SHORT WAVE...IS EXPECTED TO DISSIPATE THROUGH THE NEXT 24 HOURS AS THE SHORT WAVE ALSO DISSIPATES. GIVEN AL THIS...A CLEARING TREND SHOULD BE OBSERVED ACROSS OUR AREA THROUGH THE NEXT 12 OR SO HOURS...WITH MOSTLY CLEAR SKIES EXPECTED THEREAFTER. WENT AHEAD AND KEPT THE INCREASED CLOUD COVER GOING IN THE FORECAST FOR NORTHWESTERN PORTIONS OF THE CWA THROUGH THIS EVENING TO ACCOUNT FOR THE CURRENT STRATUS...WITH MOSTLY CLEAR SKIES FORECAST ACROSS MOST ALL OF THE CWA 06Z ONWARD. THE COMBINATION OF CLEARING SKIES...A DECREASING LOW LEVEL WIND FIELD...AND THE INFLUX OF A COOLER AND DRIER LOW LEVEL AIRMASS INTO OUR AREA AS THE WEAK SURFACE RIDGE INFILTRATES THE REGION...WILL PROMOTE A CHILLY NIGHT ACROSS THE CWA WITH ~30-DEGREE TEMPERATURE DROP-OFFS LIKELY ACROSS MUCH OF THE AREA. THE ONLY EXCEPTION MAY BE ACROSS OUR NORTHWESTERN CWA WHERE LINGERING CLOUDS MAY LIMIT TEMPERATURE DROP-OFFS FROM REACHING THEIR FULL POTENTIAL. MET/NAM GUIDANCE SEEMS TO HAVE A GOOD HANDLE ON THIS AND OPTED TO PLAY CLOSE TO THIS GUIDANCE FOR LOWS TONIGHT...WHICH PRESENTS TEMPERATURES RANGING FROM THE MID-20S TO THE MID-30S. THE SURFACE RIDGE SHOULD PASS OFF TO THE EAST OF OUR AREA SATURDAY AFTERNOON...THUS ALLOWING FOR WEAK LOW LEVEL RETURN FLOW BY LATE IN THE DAY. WITH MOSTLY CLEAR SKIES AND A FAIRLY DRY LOW LEVEL AIRMASS...SATURDAY TEMPERATURE-RISES ON THE ORDER OF 25-30 DEGREES SEEM REASONABLE...WHICH PRESENTS SATURDAY HIGH TEMPERATURES GENERALLY IN THE MID TO UPPER 50S. LONG TERM...SATURDAY NIGHT THROUGH FRIDAY. MOST DAYS WILL SEE ABOVE NORMAL HIGH TEMPERATURES EXCEPT FOR TUESDAY. IN ADDITION...OUTSIDE OF A FEW ISOLATED SPRINKLES IT SHOULD BE A DRY PERIOD. SATURDAY NIGHT...A WEAK SHORTWAVE TROUGH WILL TRACK SOUTHEAST THROUGH IOWA...AND CLOUDS WILL INCREASE OVERNIGHT ACROSS IOWA AND NEBRASKA. A FEW SPRINKLES MAY EXTEND AS FAR WEST AS CENTRAL NEBRASKA...BUT MOST AREAS WILL REMAIN DRY. WE CAME VERY CLOSE TO PULLING THE SPRINKLES OUT OF THE FORECAST...BUT WILL LEAVE THEM IN THE FORECAST THROUGH ONE MORE MODEL CYCLE. SUNDAY...A WEAK RIDGE IN THE GENERALLY NORTHWEST FLOW REGIME WILL BE PASSING THROUGH DURING THE DAY AND THE SFC WIND WILL BE LIGHT...BUT WITH A SOUTHWESTERLY COMPONENT THROUGH MOST OF THE DAY. THEREFORE...EXPECT SUNDAY WILL BE A FEW DEGREES WARMER THAN SATURDAY AND ABOVE NORMAL WITH HIGH TEMPERATURES IN THE 60S. SUNDAY NIGHT...THE NEXT SHORTWAVE TROUGH EMBEDDED WITHIN THE NORTHWEST FLOW WILL SWING INTO NEBRASKA. THIS WILL BRING DOWN A COLD FRONT AND A CHANCE OF MORE SPRINKLES. CLOUDS WILL HELP TO KEEP LOW TEMPERATURES UP A BIT WITH UPPER 30S TO LOWER 40S EXPECTED. MONDAY...COOLER AIR WILL CONTINUE TO FILTER IN BEHIND THE SUNDAY NIGHT SHORTWAVE/COLD FRONT. TEMPERATURES AT 850MB MAY FALL TO AROUND 0C ACROSS EASTERN ZONES AND EXPECT SFC TEMPERATURES TO BE AROUND 10 DEGREES COOLER THAN ON SUNDAY WITH HIGHS IN THE 50S. TUESDAY THROUGH FRIDAY...AN UPPER RIDGE WILL BUILD ACROSS THE PLAINS AS A LARGE UPPER TROUGH BEGINS TO DIG OVER THE WESTERN CONUS. THIS WILL BE A WARM AND DRY WEATHER PATTERN FOR OUR FORECAST AREA WITH HIGHS GENERALLY IN THE 60S. && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1016 PM EST SUN NOV 4 2012 .SYNOPSIS... CLOUDS...FLURRIES...AND SPRINKLES...WILL PERSIST THROUGH MUCH OF THE NIGHT FOR PORTIONS OF CENTRAL NEW YORK...AS MOISTURE CONTINUES TO STREAM OFF LAKE ONTARIO. HIGH PRESSURE WILL BUILD DOWN ACROSS THE REGION MONDAY AND TUESDAY...TO BRING DRY BUT CHILLY WEATHER. && .NEAR TERM /UNTIL 6 AM MONDAY MORNING/... JUST SOME VERY LGT RETURNS ON THE RADAR THIS EVE. WILL KEEP SPRINKLES AND FLURRIES IN OVRNGT. NAM DOES SHOW A CPL MORE WEAK WVS SLIDING THRU LATE TNGT AND EARLY MON...BUT THE HRRR KEEPS ANY LGT PCPN NEAR THE LAKE SHORE OVER WRN NY. WITH THE MORE NLY FLOW...XPCT CHANCE FOR ANY LGT LE TO BE MORE PSBL OVER THE WRN ZONES AS THE NGT WEARS ON. PRVS DISC BLO. 3 PM UPDATE... CLOUDS CONTINUE TO HANG TOUGH THROUGH THE CWA LATE THIS AFTN. HOWEVER...THERE ARE SOME EARLY SIGNS OF IMPROVEMENT BEGINNING TO SHOW UP...WHICH SHOULD TAKE PLACE IN OUR ERN ZNS TNT. THE CHARACTER OF THE CLOUD COVER IS TAKING ON A MORE OPEN CELLULAR APPEARANCE EAST OF THE I-81 CORRIDOR ATTM...AND FAIRLY SIG HOLES HAVE OPENED UP IN THE EARLIER EXPANSIVE SC SHIELD UP OVER SRN QUE. SINCE OUR LOW-LVL FLOW IS EXPECTED TO TURN MORE INTO THE N AND EVEN NNE OVERNIGHT...WE THINK THIS TYPE OF ENVIR WILL SETTLE ACRS OUR ERN ZNS...WITH AT LEAST PTL CLEARING ANTICIPATED AFTER 00-03Z. MEANWHILE...FARTHER W THROUGH THE FINGER LKS RGN...WHERE A LOW-LVL MOIST FEED WILL STILL BE MAINTAINED S OF LK ONT...CLDS SHOULD BE MORE STUBBORN...WITH A FEW FLRYS EVEN ANTICIPATED...AS BLYR CAA IS RENEWED FOR A BRIEF PD OVERNIGHT. OUR NE PA ZNS SHOULD SEE SOME CLEARING DURG THE NGT...EXCPT FOR PERHAPS BRADFORD/WRN SUSQ CNTYS...WHERE THE ABV MENTIONED CLOUDS FROM LK ONT COULD MOVE IN FOR A TIME. && .SHORT TERM /6 AM MONDAY MORNING THROUGH TUESDAY NIGHT/... 305 PM UPDATE... QUIET WX FORESEEN THIS PD...WITH SFC RIDGING OUR DOMINANT FEATURE. AM CLDS/SCTD FLRYS MON IN OUR WRN ZNS...SHOULD HAVE A TENDENCY TO BREAK UP BY 18Z...AS THE DEPTH OF DRIER AIR FINALLY OVERWHELMS THE MOIST BLYR ENVIR. THEREAFTER...WE EXPECT MAINLY CLR SKIES MON NGT...AND SUNNY SKIES ON TUE. MID TO HIGH-LVL CLDS MAY WELL BEGIN TO INCREASE LTR TUE NGT...FAR IN ADVANCE OF THE WELL ADVERTISED EAST COAST STORM SLATED TO ARRIVE IN THE LONG-TERM PD (MORE ON THIS BELOW). && .LONG TERM /WEDNESDAY THROUGH SUNDAY/... MAIN FEATURE TO WATCH DURING THE PERIOD WILL BE A STORM DEVELOPING OFF THE MID-ATLANTIC COAST LATE WEDNESDAY INTO EARLY FRIDAY. LATEST MODEL RUNS HAVE SHOWN THE GFS TRENDING SLIGHTLY FARTHER EAST WITH THE STORM WHILE THE ECMWF IS CLOSER TO THE COAST. THE CANADIAN MODEL APPEARS TO BE A BIT OF A COMPROMISE... MAYBE SLIGHTLY LEARNING TOWARD THE ECMWF. RUN TO RUN CONSISTENCY WITH THE MODELS HAS BEEN PRETTY GOOD WITH THIS FEATURE OVER THE PAST COUPLE OF DAYS... HOWEVER MINOR POSITIONING DIFFERENCES WILL MAKE A BIG DIFFERENCE IN THE WEATHER FOR OUR AREA. THE GFS WOULD BASICALLY INDICATE A NON- EVENT FOR OUR AREA... THE CANADIAN WOULD INDICATE A MAJOR SNOW STORM FOR THE EASTERN HALF OF THE AREA... AND THE ECMWF ACTUALLY INDICATES THE MOST SNOW FOR OUR CENTRAL COUNTIES... ALONG THE I-81 CORRIDOR. OBVIOUSLY TOO SOON TO PIN DOWN DETAILS AT THIS POINT... BUT IT DOES APPEAR THAT A SIGNIFICANT EVENT IS POSSIBLE. HAVE KEPT OUR CURRENT RAIN/SNOW FORECAST FOR THE AREA WITH HIGHEST POPS WEDNESDAY NIGHT INTO THURSDAY. THE ONLY ADJUSTMENT WITH THIS PACKAGE WAS TO SLIGHTLY SLOW DOWN THE ONSET OF PRECIPITATION DURING THE AFTERNOON WEDNESDAY. THE STORM WINDS DOWN BY FRIDAY... AND AT THIS POINT NEXT WEEKEND LOOKS DRY WITH A WARMING TREND. && .AVIATION /03Z MONDAY THROUGH FRIDAY/... 630 PM UPDATE... CLOUDY SKIES CONTINUE TONIGHT BEFORE BECOMING SCATTERED MONDAY. WITH A SHORT WAVE GOING THROUGH AND CAA LAKE EFFECT RAIN AND SNOW SHOWERS WILL CONTINUE AT LEAST THIS EVENING. WITH A NW FLOW KRME SHOULD REMAIN VFR BEING TOO FAR EAST...WHILE KAVP WILL BE MOSTLY VFR BEING TOO FAR SOUTH OF LAKE ONTARIO. REST OF SITES MVFR CIGS TONIGHT IMPROVING TO VFR 12 TO 15Z MONDAY. BECOMING SCATTERED AVP AND RME IN THE MORNING THEN REST IN THE AFTN. WINDS WILL BE NW AT AROUND 5 KTS TONIGHT.. AND NW AT 7 TO 10 KTS MONDAY. OUTLOOK... MON NGT AND TUE...VFR. WED TO THU NGT...MVFR IN RAIN AND SNOW. FRI...MVFR IN CENTRAL NY WITH LAKE EFFECT SHOWERS. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...NONE. NY...NONE. && $$ SYNOPSIS...MLJ NEAR TERM...DGM/MLJ SHORT TERM...MLJ LONG TERM...MSE AVIATION...TAC
AREA FORECAST DISCUSSION
NWS BUFFALO NY
340 PM EDT SAT NOV 3 2012 .SYNOPSIS... A PERSISTENT UPPER TROUGH WILL GRADUALLY YIELD TO HIGH PRESSURE APPROACHING FROM THE UPPER LAKES. LIGHT RAIN OR SNOW SHOWERS WILL LINGER TONIGHT...BUT THEN END SUNDAY AS MORNING CLOUDS GIVE WAY TO SOME PARTIAL SUNSHINE. DRY WEATHER WILL LAST THROUGH THE FIRST HALF OF NEXT WEEK...ALTHOUGH IT WILL STILL BE CHILLY WITH BELOW AVERAGE TEMPERATURES. && .NEAR TERM /THROUGH SUNDAY/... THROUGH THIS EVENING...NOT MUCH WILL CHANGE AS AN UPPER TROF ACROSS THE CANADIAN MARITIMES CONTINUES TO SPIN COOL AND MOIST AIR ACROSS THE REGION. ON THE BACK OF THIS TROF...THERE WILL BE LIMITED LIFT...WITH LAKE INFLUENCES AND UPSLOPING THE MAIN FACTORS TO CONSIDER. SINCE COLD AIR IS FAIRLY SHALLOW...LAKE INDUCED CAPES WILL CONTINUE TO BE MODEST...GENERALLY 200 TO 300 J/KG. THE RESULT WILL BE A CONTINUATION OF THE PATTERN WE HAVE BEEN IN...WITH GENERALLY SCATTERED AND/OR LIGHT RAIN OR SNOW SHOWERS. ROUGHLY SPEAKING A SURFACE TEMPERATURE OF 35 DEGREES SEEMS TO BE THE RAIN TO SNOW CUT-OFF. THIS LIMITS SNOW SHOWERS MAINLY TO HIGHER TERRAIN...WITH ELSEWHERE MAINLY RAIN. CONSISTENT WITH SPOTTER REPORTS...MOST LOCATIONS REPORTING AN ACCUMULATION WERE ABOVE 1700 FEET...WITH ANY LIGHT ACCUMULATIONS THIS EVENING LIKELY TO REMAIN ACROSS THIS HIGHER TERRAIN. LATER TONIGHT WARMER AIR ALOFT WILL BUILD IN FROM THE WEST. BUFKIT FORECAST SOUNDINGS FROM THE NAM AND RAP WARM THE 700-850MB LAYER...WITH THE COLDEST TEMPERATURES BENEATH THIS LAYER -6C TO -8C. THIS SHOULD NOT BE COLD ENOUGH TO SUPPORT SNOW...WITH ANY PRECIPITATION LIKELY TO FALL AS A LIGHT SLEET OR DRIZZLE. FORTUNATELY...THE SHALLOW MOISTURE LAYER AND LIMITED INSTABILITY WILL LIMIT THE CHANCE FOR PRECIPITATION...WITH ONLY A SLIGHT CHANCE OF MEASURABLE PRECIPITATION. THE PROBLEM THIS POSES...IS THAT IF SURFACE TEMPERATURES DROP BELOW FREEZING...SOME PATCHY FREEZING DRIZZLE CANNOT BE RULED OUT ACROSS UPSLOPE REGIONS IN THE SOUTHERN TIER. CONFIDENCE IN THIS OCCURRING IS FAR SHY OF ANY HEADLINES...BUT IT WARRANT MONITORING OVERNIGHT. COLD AIR WILL HANG IN A BIT LONGER TO THE EAST...WITH PRECIPITATION FALLING AS EITHER RAIN OR SNOW. IN GENERAL...FEEL MOS NUMBERS ARE TOO COLD FOR TONIGHTS LOWS...WITH PERSISTENT CLOUD COVER LIKELY TO REMAIN ACROSS MOST OF THE REGION. THERE STILL SHOULD BE SUB-FREEZING TEMPERATURES ACROSS INTERIOR SECTIONS AND HIGHER TERRAIN...WITH LOCATIONS NEAR THE LAKES NORTH OF I-90 AND WEST OF I-81 LIKELY TO REMAIN ABOVE FREEZING. THIS SAID...ANY LOCALIZED CLEARING WOULD ALLOW TEMPERATURES TO DROP SEVERAL DEGREES BELOW THE FORECAST. ON SUNDAY...SURFACE HIGH PRESSURE WILL FINALLY START TO MAKE A MEANINGFUL PUSH INTO THE REGION. DESPITE THIS...A CONTINUED NORTHWESTERLY FLOW OFF THE LAKES WILL LIKELY KEEP CLOUDS IN FOR THE MORNING HOURS...AND WELL INTO THE AFTERNOON. EXPECT SOME BREAKS OF SUN FOR MOST LOCATIONS...BUT THESE MAY NOT BE ALL THAT LONG. HOWEVER...THE DRYING AIR SHOULD CAUSE ANY LINGERING SHOWERS TO TAPER OFF BY LATE MORNING. TEMPERATURES WILL STAY ON THE COOL SIDE...WITH HIGHS IN THE UPPER 30S TO LOWER 40S. && .SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY NIGHT/... THE SHORT TERM PERIOD LOOKS RELATIVELY QUIET AS A DRY AIR MASS GAINS CONTROL INTO THE GREAT LAKES AND OHIO VALLEY...COURTESY OF CANADIAN HIGH PRESSURE BUILDING SOUTHWARD INTO THE REGION. THERE COULD BE SOME MINOR LAKE RESPONSE SUNDAY NIGHT WITHIN WEAK NORTHWEST LOW LEVEL FLOW...THOUGH OVERALL DRY AMBIENT AIR AND RELATIVELY LOW LAKE DELTA T/S WOULD SUGGEST ONLY AN INCREASE IN LAKE CLOUDS SOUTHEAST OF LAKE ONTARIO AND ALONG THE SOUTHERN TIER. WESTERN AND CENTRAL NEW YORK WILL BE IN BETWEEN SYSTEMS ON MONDAY AND TUESDAY WITH SHORTWAVE RIDGING AND RESULTING SURFACE HIGH PRESSURE ENSURING A FAIR...ALBEIT CHILLY DAYS. MODEL CROSS SECTIONAL FIELDS WOULD SUGGEST MOSTLY SUNNY DAYS APART FROM SOME DIURNAL STRATOCU...ESPECIALLY MONDAY. 850 MB TEMPERATURES AROUND -6C WOULD SUGGEST HIGHS STRUGGLING TO GET OUT OF THE 30S MONDAY. MONDAY NIGHT LOOKS TO BE A GOOD RADIATIONAL COOLING NIGHT WITH OVERNIGHT LOWS DROPPING INTO THE 20S...WITH A FEW TEENS ACROSS THE NORMALLY COLDER INTERIOR SECTIONS OF THE SOUTHERN TIER AND EAST OF LAKE ONTARIO. TEMPERATURES LOOK A FEW DEGREES WARMER FOR TUESDAY...BUT PROBABLY NO WARMER THAN THE LOWER 40S. && .LONG TERM /WEDNESDAY THROUGH SATURDAY/... LATEST MEDIUM RANGE GUIDANCE CONTINUING TO SUGGEST THAT CONDITIONS WILL BE FAVORABLE FOR SIGNIFICANT CYCLOGENESIS OFF THE CAROLINA COAST AT THE START OF THE PERIOD. CONFIDENCE HAS INCREASED THAT A DEEP NORTHEAST COASTAL STORM WILL EVOLVE IN THE LATE WEDNESDAY THROUGH THURSDAY TIME FRAME...ALTHOUGH THERE STILL REMAINS DIFFERENCES IN TIMING AND STRENGTH OF THE OVERALL SYSTEM. 12Z GFS FASTER IN MOVING THE COASTAL STORM NORTHWARD THAN THE ECMWF. THE ECWMF REMAINS FARTHER WEST THAN THE GFS...ALTHOUGH THE 12Z GFS HAS MOVED LEFT FROM PREVIOUS RUNS. DESPITE THE CONTINUED MODEL DIFFERENCES...STILL FEEL THAT WESTERN NEW YORK WILL HAVE A LIMITED PRECIPITATION OR WIND THREAT FROM THIS SYSTEM...HOWEVER CENTRAL NEW YORK...ESPECIALLY THE NORTH COUNTRY COULD STILL HAVE SEVERAL SIGNIFICANT IMPACTS...INCLUDING HEAVY RAINFALL...ACCUMULATING HIGHER ELEVATIONS SNOWS AND A WIND POTENTIAL. THIS SYSTEM STILL BEARS WATCHING FOR THAT PORTION OF OUR FORECAST AREA. ONCE THE NORTHEAST COASTAL LOW LIFTS OUT...A BURGEONING PACIFIC CLOSED LOW COMBINED WITH A DIGGING TROUGH OVER THE WESTERN CONUS WILL PROMOTE QUICKLY BUILDING MID LEVEL HEIGHTS AND ANTICYCLONIC VORTICITY ADVECTION INTO THE OHIO VALLEY AND GREAT LAKES. EXPECT DRY CONDITIONS WITH MODERATING TEMPERATURES IN THE FRIDAY THROUGH SATURDAY TIME FRAME...WITH ABOVE NORMAL READINGS LIKELY BY THE WEEKEND. && .AVIATION /20Z SATURDAY THROUGH THURSDAY/... MOST LOCATIONS STARTED THE 18Z TAF CYCLE WITH MVFR CIGS JUST BELOW 3000 FEET...BUT THESE SHOULD CONTINUE TO SLOWLY RISE LATE THIS AFTERNOON. TIMING WILL VARY FROM SITE TO SITE...WITH SOME POSSIBLY REMAINING MVFR FOR THE DURATION. SCATTERED RAIN AND SHOWERS WILL PERSIST ACROSS HIGHER TERRAIN TODAY...BUT SHOULD NOT IMPACT TAF SITES. TONIGHT...EXPECT A LOWERING OF CIGS WITH DIURNAL LOWERING OF THE INVERSION...AND A RETURN TO MVFR CIGS. LOWEST CIGS WILL BE AT JHW...WHERE A PERIOD OF IFR IS POSSIBLE. HIGH PRESSURE BUILDING IN FROM THE WEST WILL FINALLY ALLOW CLOUDS TO LIFT AND SCATTER ON SUNDAY...HOWEVER THIS WILL BE A SLOW PROCESS AS WELL...WITH MVFR CIGS TO LINGER WELL INTO THE DAY IN MOST LOCATIONS. OUTLOOK... SUNDAY THROUGH WEDNESDAY...MAINLY VFR. THURSDAY...MVFR/VFR. A CHANCE OF RAIN OR SNOW. && .MARINE... MARGINAL SCA CONDITIONS PERSIST ON LAKE ONTARIO...WITH 15 TO 20 KNOT WINDS MAINTAINING SOME 5 FOOT WAVES ON ITS SOUTH SHORES. WINDS WILL GRADUALLY DIMINISH AND SHIFT MORE TO THE NORTH TONIGHT...WHICH SHOULD EVENTUALLY ALLOW THE HEADLINES TO BE DROPPED. AFTER THIS...HIGH PRESSURE WILL BUILD ACROSS THE WATERS...AND CONTINUE TO INFLUENCE THE REGION THROUGH MID-WEEK. THIS WILL LIKELY KEEP CONDITIONS BELOW SMALL CRAFT CRITERIA DURING THE PERIOD. && .CLIMATE... OUR WRITTEN OCTOBER CLIMATE SUMMARIES FOR BOTH BUFFALO AND ROCHESTER CAN BE FOUND UNDER THE CLM PRODUCT ON OUR WEBPAGE UNDER LOCAL CLIMATE. SOME HIGHLIGHTS INCLUDE: FOR BUFFALO WE HAD THE 2ND MOST MEASURABLE PRECIPITATION DAYS IN OCTOBER`S RECORDED HISTORY (SINCE 1871) WITH 22 OF THE 31 DAYS MEASURING PRECIPITATION. THE ALL-TIME RECORD WAS SET BACK IN 1890 WITH 25 DAYS. FOR A 6TH STRAIGHT MONTH WE HAD A MONTH FINISH WITH ABOVE NORMAL TEMPERATURES...WITH BUFFALO`S 52.2F SETTING THE MONTH 1.4F ABOVE NORMAL. FOR ROCHESTER WE HAD A TIE FOR 6TH GREATEST NUMBER OF DAYS WITH MEASURABLE PRECIPITATION...WITH 18 DAYS. THE RECORD FOR THE MONTH OF OCTOBER IS 21 DAYS WHICH WAS SET BACK IN THE YEAR 1988. LIKE BUFFALO ROCHESTER ALSO HAS HAD 6 STRAIGHT MONTHS FINISH WITH ABOVE NORMAL WARMTH. THE 52.8F DEGREES WAS 2.2F ABOVE THE NORM. OVER AN 8 DAY PERIOD...OCTOBER 26TH THROUGH NOVEMBER 2ND...BUFFALO HAS RECEIVED AT LEAST A TENTH OF AN INCH OF PRECIPITATION. THESE 8 CONSECUTIVE DAYS TIES A RECORD FOR GREATEST NUMBER OF CONSECUTIVE DAYS WITH AT LEAST A TENTH OF AN INCH OF PRECIPITATION. THE LAST OCCURRENCE WAS IN JANUARY 1999. && .BUF WATCHES/WARNINGS/ADVISORIES... NY...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 9 AM EST SUNDAY FOR LOZ043-044. SMALL CRAFT ADVISORY UNTIL 3 AM EST SUNDAY FOR LOZ042-045. && $$ SYNOPSIS...APFFEL NEAR TERM...APFFEL SHORT TERM...TMA LONG TERM...TMA AVIATION...APFFEL MARINE...APFFEL/TMA CLIMATE...THOMAS
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
256 PM CDT SAT NOV 3 2012 .SHORT TERM... CHALLENGES IN THE SHORT TERM FORECAST WILL BE PCPN CHANCES AND TEMPS NOW THAT THERE IS SOME SNOW COVER OUT THERE. FOG COULD ALSO BE AN ISSUE TONIGHT. PREFER A MODEL BLEND TODAY. TONIGHT...LAST PIECE OF VORTICITY APPEARS TO BE SPINNING JUST TO THE SW OF KFAR RIGHT NOW WITH AN AREA OF LIGHT SNOW ASSOCIATED WITH IT. HAS YET TO REACH TO KFAR AND MOORHEAD HAS ONLY PICKED UP A FEW SPITS SO CONFIDENCE IS NOT HIGH THAT MUCH WILL REACH KFAR AND AREAS TO THE EAST. THERE ARE A FEW BREAKS IN THE CLOUDS TRYING TO MOVE INTO THE FAR NORTHEAST BUT WILL ALSO KEEP THINGS MOSTLY CLOUDY TONIGHT. WILL LEAVE THE MENTION OF EARLY EVENING FLURRIES ACROSS THE FAR SOUTH. ANOTHER CONCERN IS FOG. THERE HAS BEEN AN AREA OF FOG THAT HAS NOT GONE AWAY TODAY UP ALONG THE CANADIAN BORDER IN ND. WILL KEEP THIS AREA FOGGY TONIGHT AND SLOWLY EXPAND THE AREA TO THE SOUTH. NOT EXACTLY SURE HOW WIDESPREAD IT MAY BECOME BUT TEMP/DEW POINTS ARE CLOSE OVER MOST OF EASTERN ND NOW AND WINDS STAY LIGHT OVERNIGHT. SUN-TUE...NEXT SYSTEM QUICKLY MOVES INTO THE WESTERN FA SUNDAY MORNING THEN EXPANDS TOWARD THE RED RIVER VALLEY DURING THE DAY. MODELS TODAY LOOK A LITTLE FURTHER WEST WITH THE MAIN BAND OF PCPN. NAM SEEMS TO BE THE FURTHEST EAST SO WILL GIVE THE LEAST WEIGHT TO THAT SOLUTION FOR NOW. THIS AREA OF PCPN SHOULD SINK SOUTHWARD SUN NIGHT AFFECTING MAINLY THE SOUTHERN VALLEY. PCPN TYPE FOR THIS ROUND STILL IS TRICKY. TEMPS SHOULD BE COOLEST ACROSS THE DEEPER SNOW AROUND THE KDVL REGION SO PCPN SHOULD BE SNOW THERE. WILL KEEP THE MIX OF RAIN OR SNOW FOR OTHER AREAS. SO SNOWFALL AMOUNTS COME OUT TO LESS THAN AN INCH ACROSS THE KDVL REGION TO JUST A DUSTING FOR THE REST OF EASTERN ND. LATEST HPC SNOWFALL GRAPHICS SEEM TO SUPPORT THIS IDEA AS WELL. SHOULD GET A QUICK BREAK MON MORNING BEFORE THE NEXT PCPN SHOT COMES IN MON AFTERNOON AND LINGERS INTO TUE. THIS TIME MOST OF THE AREA LOOKS TO GET SOMETHING BUT MAINLY THE NORTH/NE FA. AGAIN PCPN TYPE A TOUGH CALL BUT FOR MOST OF THE EVENT TEMPS LOOK TO BE WARM ENOUGH FOR JUST LIQUID PCPN. HOWEVER THERE COULD BE TIMES MON NIGHT INTO EARLY TUE THAT SOME AREAS COULD SEE A MIX OF RAIN OR SNOW. .LONG TERM (TUESDAY NIGHT-SATURDAY)...12Z MODELS ALL INDICATE THE SAME LARGE SCALE PATTERN. PERIOD WILL BEGIN WITH THE REGION UNDER THE INFLUENCE OF RIDGING...TRANSITIONING TO SOUTHWEST FLOW ALOFT BY LATE IN THE WEEK. THE FIRST HALF OF THE PERIOD WILL BE MOSTLY DRY. THEN...EACH MODEL INDICATES A STRONG SYSTEM FOR LATE IN THE PERIOD. HOWEVER...THE ECMWF IS SLOWER AND WEST OF THE GFS. THIS HAS IMPLICATIONS ON TIMING OF BEST PRECIP CHANCES AND P-TYPE. ALTHOUGH THE ECMWF TENDS TO BE MORE ACCURATE IN THESE SITUATIONS...WILL STICK CLOSE TO THE ALLBLEND SOLUTION GIVEN THIS SYSTEM WILL BE A DAY 6/7 EVENT. SINCE EACH MODEL INDICATES A DIFFERENT P-TYPE...WILL GO WITH RAIN/SNOW MOST PLACES. && .AVIATION...THE REGION IS IN A TRANSITION ZONE FROM WEST TO EAST OF IFR TO VFR CONDITIONS. THIS WILL LEAD TO A LOW CONFIDENCE FORECAST. KDVL SHOULD REMAIN IFR/MVFR THROUGH THE NIGHT. THE VALLEY SITES WILL LIKELY EXPERIENCE A PERIOD OF VFR CONDITIONS...BUT SHOULD DROP BACK DOWN TO AT LEAST MVFR BY 12Z SUNDAY. KTVF AND KBJI SHOULD REMAIN VFR THROUGH MUCH OF THE NIGHT (ALTHOUGH 18Z RAP INDICATES LOW CLOUDS POSSIBLE SUNDAY MORNING). && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ GODON/TG
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
205 AM EDT SAT NOV 3 2012 .SYNOPSIS... A LOW PRESSURE CENTER PASSES TO THE SOUTH LATE SATURDAY AND SATURDAY NIGHT. ANOTHER SYSTEM PASSES SOUTH AND EAST OF THE REGION FOR MID WEEK. && .NEAR TERM /THROUGH TODAY/... 1000PM UPDATE... APPEARS PREV FCST THINKING STILL HOLDS TRUE. CONCERNS STILL EXIST FOR SOME PATCHY -FRDZ OVERNIGHT IN N MTNS AND WILL KEEP SOME WORDING IN WX GRIDS. 730PM UPDATE... SOLID DECK OF 4 TO 5 THSD FOOT CLDS INVADING FROM NW...AFFECTING PORTIONS OF SE OH AND N WV THIS EVE. USED LATEST RUC RH FIELDS ARND 1KM AGL AS A BASE FOR SKY GRIDS OVERNIGHT. TRICK IS SW EXTENT OF THIS CLD SHIELD. THINK MUCH OF TRI STATE AREA WILL STAY VOID OF THIS WITH JUST SOME PASSING CIRRUS. WILL ORIENT A NW TO SE AXIS FROM UNI TO CRW TO N OF BKW...AND POINTS N...TO PAINT IN MOST PESSIMISTIC SKY COVER TONIGHT. NEUTRAL TMP ADVECTION NOTED AT H85 TONIGHT ALONG THIS AXIS SO FEEL GOOD ABOUT GOING OVC ACROSS N WV. SOME LIFT BENEATH H8 ON UPSLOPE FLOW ACROSS N MTNS MAY SQUEEZE OUT A FEW -SHSN. HOWEVER...WITH STOUT SUBSIDENCE ABV -10C...AM CONCERNED FOR SOME PATCHY -FR DZ. WILL CONT MENTION IN WX GRIDS ATTM. PEAKED OUT INTO TOMORROW TO PUSH BACK POPS ACROSS NE KY/S WV UNTIL LATE AFTN BASED ON LATEST MDL RUNS. PREVIOUS DISCUSSION BELOW... AT THE BEGINNING OF THE PERIOD THE UPPER 500MB LOW PROGGED TO BE LOCATED OFF THE SOUTHERN NEW ENGLAND COAST WITH NW FLOW ALOFT OVER THE AREA. AT THE SURFACE...HIGH PRESSURE WILL BE NOSING IN FROM THE NORTHWEST. GOOD FORCING FOR SUBSIDENCE WILL CONTINUE OVER THE AREA TONIGHT ON THE BACKSIDE OF THE UPPER LOW. DESPITE THIS...WILL RAMP UP POPS AGAIN TO LOW/MID CHANCE DURING THE OVERNIGHT/EARLY MORNING HOURS IN THE EASTERN HIGH TERRAIN MAINLY WEBSTER COUNTY AND POINTS NORTHEAST WITH FAVORABLE UPSLOPE CONDITIONS AND TRAPPED LLVL MOISTURE IN PLACE. DO HAVE A CONCERN HOWEVER WITH FREEZING DRIZZLE/MIST IN THOSE AREAS. NAM/GFS/SREF SOUNDINGS ARE ALL DRY AT -10C WITH GOOD SATURATION ONLY EXTENDING TO ABOUT -7C TO -8C AND SFC TEMPS WELL BELOW FREEZING. TOUGH CALL ON THIS REGARDING PRECIP TYPE HOWEVER AS OFTENTIMES IT SEEMS SOUNDINGS IN THIS AREA WOULD INDICATE FREEZING DRIZZLE YET SNOW IS STILL THE RESULT. QPF AMOUNTS ARE IN THE TWO TO FIVE HUNDREDTHS ROUGHLY. WILL LEAVE ANY ICE ACCUM OUT OF GRIDS FOR NOW AND LET EVENING SHIFT TAKE ANOTHER LOOK WITH SUBSEQUENT DATA. PRECIP SHOULD QUICKLY WIND DOWN DURING THE MORNING HOURS ACROSS THE HIGH TERRAIN. HEIGHTS INITIALLY RISE DURING THE MORNING HOURS AS UPPER LOW CONTINUES AWAY FROM AREA BUT ANOTHER S/W TROUGH DIGGING THROUGH THE CENTRAL MISS VALLEY ESSENTIALLY TURNING THE FLOW FROM NW DURING THE MORNING TO ZONAL BY END OF PERIOD. A WARM FRONT WILL EXTEND EASTWARD FROM SFC LOW OVER WEST/CENTRAL TENN TO AROUND THE NC/VA BORDER BY LATE AFT SATURDAY. SOME WEAK ISENTROPIC LIFT IS NOTED ON 300K-305K SFCS WELL ABOVE AGL AND THE SOUNDING IS VERY WEAKLY CONVECTIVE. BUT AS PREV FCST NOTED...MUCH OF THE FORCING IS FRONTOGENETIC IN NATURE AND FLOW AT H85 AND H7 ESSENTIALLY PARALLEL TO WARM FRONT...SO NOT REALLY AN OVERRUNNING SCENARIO. ELECTED TO SLOW DOWN POPS JUST A TAD BUT PREV FCST STILL HAD A GENERAL GOOD HANDLE ON PRECIP MOVING INTO THE SW ZONES BY END OF PERIOD. && .SHORT TERM /TONIGHT THROUGH MONDAY/... LOW PRESSURE PASSES S OF THE AREA THIS WEEKEND. ASSOCIATED WARM ADVECTION AND ISENTROPIC LIFT SPREADS PRECIPITATION INTO SOUTHERN PORTION OF THE AREA LATE SAT OR SAT EVENING DEPENDING UPON HOW LONG IT TAKES TO MOISTEN THE LOW LEVELS. EXPECT PRECIPITATION TO BE LIGHT GIVEN VERY ACUTE ANGLE ON PRESSURE ADVECTION ON THE 295 AND 300 K ISENTROPIC SURFACES. MAINLY A RAIN EVENT GIVEN THERMAL FIELDS. EVEN WHERE NEAR 0C AT H85...THERE IS NO MECHANISM TO GET SURFACE TEMPERATURES DOWN TO FREEZING ACROSS LOWLANDS. SOME SNOW IS POSSIBLE HIGH TERRAIN OF CENTRAL MOUNTAINS SAT NT BUT HAVE LOW CHANCE THERE ON NORTHERN EDGE OF SYSTEM. SYSTEM PULLS AWAY SUN BUT UPPER LEVEL S/W TROUGH WILL LIKELY KEEP SOME CLOUDS AROUND. THIS FEATURE EXITS FIRST THING MON MORNING...ALLOWING HIGH PRESSURE TO PROVIDE FOR A NICE START TO THE NEW WORK WEEK. WITH PRECIPITATION HYDROLOGICALLY INSIGNIFICANT...LOWS IN THE 20S TO AROUND FREEZING AND HIGHS IN THE 40S WHERE THE HIGH TERRAIN SNOW PACK IS...THE SLOW MELT CONTINUES...WITH NOTHING MORE THAN LOCALIZED SMALL STREAM AND CREEK ISSUES WHERE STORM DEBRIS CREATES BLOCKAGES. IT LOOKS LIKE SWE VALUES IN THE SNOW PACK ARE DOWN TO THE TWO TO FOUR INCH RANGE. BLENDED IN BIAS CORRECTED ADJMET ON TEMPERATURES EARLY ON AND THEN BIAS CORRECTED CONSALL - OVERALL NO MAJOR CHANGES INVOLVED. && .LONG TERM /MONDAY NIGHT THROUGH FRIDAY/... USED A BLEND OF THE ECMWF AND ECMWF ENSEMBLE MEAN FOR THIS PERIOD. THIS WOULD HAVE A STORM SYSTEM SOUTH AND EAST OF THE REGION POSSIBLY GRAZING THE AREA FOR MID WEEK. A WARM FRONT WOULD THEN PUSH NORTHWARD TOWARD THE END OF THE WEEK. && .AVIATION /06Z SATURDAY THROUGH WEDNESDAY/... 06Z SATURDAY THRU 06Z SUNDAY... SHIELD OF STRATUS CLOUDS...VFR CEILINGS LOWLANDS AND MVFR CIGS MOUNTAINS...WILL PREVAIL THRU 12Z NORTH OF A CMH-CRW-BKW LINE. ELSEWHERE MOSTLY CLEAR. AFTER 12Z...STRATUS ERODES FROM SOUTHWEST TO NORTHEAST...BECOMING VFR BY 18Z ALL LOCATIONS. MID CLOUDS INCREASE FROM THE WEST AFTER 18Z AS A WEAK LOW PRESSURE SYSTEM APPROACHES. SOME SCATTERED LIGHT RAIN SHOWERS SOUTHWEST AFTER 21Z...BUT STILL VFR. AFTER 00Z...SOME LIGHT PRECIPITATION...MOSTLY SOUTH...AS THE SYSTEM PASSES JUST SOUTH OF OUR AREA. THIS PRECIP SHOULD EXIT MOST AREAS AROUND 06Z. SNOW POSSIBLE MAINLY ABOVE 3000 FEET AGL. IN ANY CASE...VFR WILL PREVAIL...POSSIBLY BRIEF MVFR IN ANY HEAVIER SHOWER. A WEAK SYS WILL PASS MAINLY TO S THRU TN VALLEY LATE SAT. HOWEVER...ENOUGH MOISTURE AND LIFT MAY ALLOW FOR SOME -SHRA ACROSS S WV/SW VA TOWARD THE END OF TAF PERIOD. FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z SUNDAY... FORECAST CONFIDENCE: MEDIUM. ALTERNATE SCENARIOS: TIMING OF CIG HEIGHTS AND PRECIP CONDITIONS AT EKN MAY VARY. EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY OF WFO FORECAST TO AVAILABLE MODEL INFORMATION: H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL. M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS. L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL. DATE SAT 11/03/12 UTC 1HRLY 06 07 08 09 10 11 12 13 14 15 16 17 EDT 1HRLY 02 03 04 05 06 07 08 09 10 11 12 13 CRW CONSISTENCY H H H H H H H H H H H H HTS CONSISTENCY H H H H H H H H H H H H BKW CONSISTENCY H H H H H H H H H H H H EKN CONSISTENCY H H H M H M M H H M M H PKB CONSISTENCY H H H H H H H H H H H H CKB CONSISTENCY M M M H M M M M M M H H AFTER 06Z SUNDAY... NO WIDESPREAD IFR EXPECTED. && .RLX WATCHES/WARNINGS/ADVISORIES... WV...NONE. OH...NONE. KY...NONE. VA...NONE. && $$ SYNOPSIS...TRM/RPY/50 NEAR TERM...50/30 SHORT TERM...TRM LONG TERM...RPY AVIATION...JMV
AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA
NWS SIOUX FALLS SD
1225 PM CDT SAT NOV 3 2012 .DISCUSSION....../ISSUED AT 905 AM CDT/ QUITE A BIT OF CLOUDS STREAMING SOUTHEAST ACROSS THE CWA THIS MORNING...AND SHOULD REMAIN A MOSTLY CLOUDY DAY MOST PLACES. A LITTLE MORE SUN MAY BE FOUND ACROSS THE FAR SOUTH NEAR THE MISSOURI RIVER. CLOUD COVER WILL AFFECT HIGH TEMPERATURES...WITH MOST PLACES SEEING HIGHS IN THE LOWER TO MID 40S. DID BUMP UP CLOUD COVER IN GRIDS FOR THE REST OF TODAY. && .AVIATION.../FOR THE 12Z TAFS/ STRATUS EXPECTED TO PERSIST THROUGH 18Z SUNDAY...ESPECIALLY ALONG AND NORTH OF INTERSTATE 90. CEILINGS GENERALLY BETWEEN OVC030 TO OVC050 CAN BE EXPECTED NORTH OF INTERSTATE 90 THROUGH 18Z SUNDAY. SOUTH OF INTERSTATE 90 CEILINGS NEAR OVC040 WILL BECOME SCT-BKN070 BY 00Z. THERE IS ALSO A CHANCE OF LIGHT RAIN OR LIGHT SNOW AFTER 03Z MAINLY ACROSS SOUTHWEST MINNESOTA. && .DISCUSSION.../ISSUED AT 325 AM CDT/ MULTIPLE CLOUD LAYERS FROM SC TO AC WILL BE PASSING OVER MOST OF THE FORECAST AREA TODAY WITH ONLY THE FAR SOUTHWEST CORNER HAVING HOPE FOR SOME DECENT SUNSHINE. SOME OF THE LOWER DECKS MAY TEND TO BREAK UP LATER IN THE DAY BUT HIGHER AC SEEN ON LATEST IMAGERY IS PINNED BY MODELS TO PASS OVER OUR SOUTHERN AREA. MEANWHILE...RUC INDICATED SOME LIFT WITH THE CURRENT MID DECK WHICH SEEMS RESPONSIBLE FOR THE FEW SPRINKLES MOVING ACROSS OUR NORTH. GOING BY RUC AND OTHER MODELS LACK OF LIFT DURING THE DAY...WILL NOT EXTEND THOSE SPRINKLES PAST 12Z/7 AM CDT RIGHT NOW. ALL THE CLOUDS WILL HAVE THE EXPECTED DAMPENING OF HIGH TEMPERATURES WHICH SHOULD AGAIN BE LOWER THAN GUIDANCE. NOT A BAD DAY THOUGH WITH WINDS LIKELY HOLDING TO LESS THAN 10 MPH. PERHAPS LATE IN THE DAY OR THIS EVENING SKIES OVERALL WILL PARTIALLY CLEAR OVER THE SOUTHWEST HALF OF OUR FORECAST AREA. WILL KEEP A SLIGHT CHANCE OF LIGHT RAIN OR SNOW NORTHEAST CORNER FOR THIS EVENING AS THE GFS DEPICTION OF MID LEVEL MOISTURE AND A LITTLE LIFT FITS OUR EARLIER FORECAST OF THIS. THE DECREASE IN CLOUDS MAY EXTEND INTO OUR EASTERN/NORTHEASTERN AREA EARLY SUNDAY EVEN AS CLOUDS FROM DIGGING UPPER WAVE START TO INCREASE AGAIN FROM THE WEST. NAM IS THE OBVIOUS OUTLIER ON THE BEHAVIOR OF THIS SYSTEM AND WILL GO FOR THE DIGGING NATURE OF SYSTEM INDICATED BY THE GFS...EC...AND EVEN THE PLACID CANADIAN. THIS MEANS KEEPING THE THREAT OF RAIN INCREASING FROM THE WEST SUNDAY AFTERNOON...AND KEEPING LIKELY RAIN THREAT OVER MUCH OF THE AREA SUNDAY NIGHT. WILL KEEP A VERY MINIMAL MENTION OF A LITTLE WET SNOW POSSIBLY MIXED IN NEAR/WEST OF THE JAMES VALLEY LATE SUNDAY NIGHT BUT NO ACCUMULATION. ASSUMING MOST MODELS HAVE THE DIGGING NATURE OF THE SYSTEM PEGGED...EXPECT A LITTLE LINGERING LIGHT RAIN CHANCE MONDAY DECREASING TO THE EAST. CLOUDS SHOULD THEN DECREASE MONDAY NIGHT WITH DECENT UPPER RIDGING AS SYSTEM MOVES SOUTHEAST AWAY FROM AREA. THE TUESDAY THROUGH FRIDAY EXTENDED PERIOD LOOKS DRY AND MILD. NOT REAL WARM AS RIDGING DOES NOT SEEM TO GET STRONG ENOUGH FAR ENOUGH NORTH TO BRING THE WARM AIR INTO SD...THOUGH IT IS POSSIBLE THAT OUR FORECAST OF 50S MAY NOT BE WARM ENOUGH LATE IN THE WEEK DEPENDING ON HOW STRING THE RIDGING TURNS OUT TO BE AHEAD OF MAJOR TROF APPROACHING FROM THE WEST NEXT WEEKEND. && .FSD WATCHES/WARNINGS/ADVISORIES... SD...NONE. MN...NONE. IA...NONE. NE...NONE. && $$
AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA
NWS SIOUX FALLS SD
905 AM CDT SAT NOV 3 2012 .DISCUSSION....../ISSUED AT 905 AM CDT/ QUITE A BIT OF CLOUDS STREAMING SOUTHEAST ACROSS THE CWA THIS MORNING...AND SHOULD REMAIN A MOSTLY CLOUDY DAY MOST PLACES. A LITTLE MORE SUN MAY BE FOUND ACROSS THE FAR SOUTH NEAR THE MISSOURI RIVER. CLOUD COVER WILL AFFECT HIGH TEMPERATURES...WITH MOST PLACES SEEING HIGHS IN THE LOWER TO MID 40S. DID BUMP UP CLOUD COVER IN GRIDS FOR THE REST OF TODAY. && .AVIATION.../FOR THE 12Z TAFS/ STRATUS EXPECTED TO PERSIST MUCH OF THE DAY TODAY...ESPECIALLY IN AREAS NORTH OF INTERSTATE 90 WHERE MVFR RANGE CEILINGS ALSO MORE LIKELY. THIS INCLUDES KHON TAF LOCATION WHERE MVFR CONDITIONS ARE EXPECTED THROUGH MIDDAY BEFORE LOWEST OF CLOUDS START TO BREAK UP A BIT AND SHIFT EAST. MVFR CONDITIONS MAY NOT COMPLETELY CLEAR OUT OF NORTHEAST 1/3 OF THE CWA THIS AFTERNOON...BUT EVEN IF THEY DO EXPECT ADDITIONAL MVFR CEILINGS TO DROP BACK INTO SOUTHWEST MN/LOCATIONS NORTHEAST OF KBKX-KSPW LINE AFTER 04/00Z. AT THIS TIME EXPECT MVFR CEILINGS TO REMAIN NORTH OF KFSD AND WILL KEEP TAF VFR FOR NOW. HOWEVER WILL BE CLOSE AND WILL HAVE TO WATCH FOR POSSIBLE BROKEN MVFR CEILINGS 14Z-19Z TIME FRAME TODAY. && .DISCUSSION.../ISSUED AT 325 AM CDT/ MULTIPLE CLOUD LAYERS FROM SC TO AC WILL BE PASSING OVER MOST OF THE FORECAST AREA TODAY WITH ONLY THE FAR SOUTHWEST CORNER HAVING HOPE FOR SOME DECENT SUNSHINE. SOME OF THE LOWER DECKS MAY TEND TO BREAK UP LATER IN THE DAY BUT HIGHER AC SEEN ON LATEST IMAGERY IS PINNED BY MODELS TO PASS OVER OUR SOUTHERN AREA. MEANWHILE...RUC INDICATED SOME LIFT WITH THE CURRENT MID DECK WHICH SEEMS RESPONSIBLE FOR THE FEW SPRINKLES MOVING ACROSS OUR NORTH. GOING BY RUC AND OTHER MODELS LACK OF LIFT DURING THE DAY...WILL NOT EXTEND THOSE SPRINKLES PAST 12Z/7 AM CDT RIGHT NOW. ALL THE CLOUDS WILL HAVE THE EXPECTED DAMPENING OF HIGH TEMPERATURES WHICH SHOULD AGAIN BE LOWER THAN GUIDANCE. NOT A BAD DAY THOUGH WITH WINDS LIKELY HOLDING TO LESS THAN 10 MPH. PERHAPS LATE IN THE DAY OR THIS EVENING SKIES OVERALL WILL PARTIALLY CLEAR OVER THE SOUTHWEST HALF OF OUR FORECAST AREA. WILL KEEP A SLIGHT CHANCE OF LIGHT RAIN OR SNOW NORTHEAST CORNER FOR THIS EVENING AS THE GFS DEPICTION OF MID LEVEL MOISTURE AND A LITTLE LIFT FITS OUR EARLIER FORECAST OF THIS. THE DECREASE IN CLOUDS MAY EXTEND INTO OUR EASTERN/NORTHEASTERN AREA EARLY SUNDAY EVEN AS CLOUDS FROM DIGGING UPPER WAVE START TO INCREASE AGAIN FROM THE WEST. NAM IS THE OBVIOUS OUTLIER ON THE BEHAVIOR OF THIS SYSTEM AND WILL GO FOR THE DIGGING NATURE OF SYSTEM INDICATED BY THE GFS...EC...AND EVEN THE PLACID CANADIAN. THIS MEANS KEEPING THE THREAT OF RAIN INCREASING FROM THE WEST SUNDAY AFTERNOON...AND KEEPING LIKELY RAIN THREAT OVER MUCH OF THE AREA SUNDAY NIGHT. WILL KEEP A VERY MINIMAL MENTION OF A LITTLE WET SNOW POSSIBLY MIXED IN NEAR/WEST OF THE JAMES VALLEY LATE SUNDAY NIGHT BUT NO ACCUMULATION. ASSUMING MOST MODELS HAVE THE DIGGING NATURE OF THE SYSTEM PEGGED...EXPECT A LITTLE LINGERING LIGHT RAIN CHANCE MONDAY DECREASING TO THE EAST. CLOUDS SHOULD THEN DECREASE MONDAY NIGHT WITH DECENT UPPER RIDGING AS SYSTEM MOVES SOUTHEAST AWAY FROM AREA. THE TUESDAY THROUGH FRIDAY EXTENDED PERIOD LOOKS DRY AND MILD. NOT REAL WARM AS RIDGING DOES NOT SEEM TO GET STRONG ENOUGH FAR ENOUGH NORTH TO BRING THE WARM AIR INTO SD...THOUGH IT IS POSSIBLE THAT OUR FORECAST OF 50S MAY NOT BE WARM ENOUGH LATE IN THE WEEK DEPENDING ON HOW STRING THE RIDGING TURNS OUT TO BE AHEAD OF MAJOR TROF APPROACHING FROM THE WEST NEXT WEEKEND. && .FSD WATCHES/WARNINGS/ADVISORIES... SD...NONE. MN...NONE. IA...NONE. NE...NONE. && $$
AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA
NWS SIOUX FALLS SD
640 AM CDT SAT NOV 3 2012 .DISCUSSION.../ISSUED AT 325 AM CDT/ MULTIPLE CLOUD LAYERS FROM SC TO AC WILL BE PASSING OVER MOST OF THE FORECAST AREA TODAY WITH ONLY THE FAR SOUTHWEST CORNER HAVING HOPE FOR SOME DECENT SUNSHINE. SOME OF THE LOWER DECKS MAY TEND TO BREAK UP LATER IN THE DAY BUT HIGHER AC SEEN ON LATEST IMAGERY IS PINNED BY MODELS TO PASS OVER OUR SOUTHERN AREA. MEANWHILE...RUC INDICATED SOME LIFT WITH THE CURRENT MID DECK WHICH SEEMS RESPONSIBLE FOR THE FEW SPRINKLES MOVING ACROSS OUR NORTH. GOING BY RUC AND OTHER MODELS LACK OF LIFT DURING THE DAY...WILL NOT EXTEND THOSE SPRINKLES PAST 12Z/7 AM CDT RIGHT NOW. ALL THE CLOUDS WILL HAVE THE EXPECTED DAMPENING OF HIGH TEMPERATURES WHICH SHOULD AGAIN BE LOWER THAN GUIDANCE. NOT A BAD DAY THOUGH WITH WINDS LIKELY HOLDING TO LESS THAN 10 MPH. PERHAPS LATE IN THE DAY OR THIS EVENING SKIES OVERALL WILL PARTIALLY CLEAR OVER THE SOUTHWEST HALF OF OUR FORECAST AREA. WILL KEEP A SLIGHT CHANCE OF LIGHT RAIN OR SNOW NORTHEAST CORNER FOR THIS EVENING AS THE GFS DEPICTION OF MID LEVEL MOISTURE AND A LITTLE LIFT FITS OUR EARLIER FORECAST OF THIS. THE DECREASE IN CLOUDS MAY EXTEND INTO OUR EASTERN/NORTHEASTERN AREA EARLY SUNDAY EVEN AS CLOUDS FROM DIGGING UPPER WAVE START TO INCREASE AGAIN FROM THE WEST. NAM IS THE OBVIOUS OUTLIER ON THE BEHAVIOR OF THIS SYSTEM AND WILL GO FOR THE DIGGING NATURE OF SYSTEM INDICATED BY THE GFS...EC...AND EVEN THE PLACID CANADIAN. THIS MEANS KEEPING THE THREAT OF RAIN INCREASING FROM THE WEST SUNDAY AFTERNOON...AND KEEPING LIKELY RAIN THREAT OVER MUCH OF THE AREA SUNDAY NIGHT. WILL KEEP A VERY MINIMAL MENTION OF A LITTLE WET SNOW POSSIBLY MIXED IN NEAR/WEST OF THE JAMES VALLEY LATE SUNDAY NIGHT BUT NO ACCUMULATION. ASSUMING MOST MODELS HAVE THE DIGGING NATURE OF THE SYSTEM PEGGED...EXPECT A LITTLE LINGERING LIGHT RAIN CHANCE MONDAY DECREASING TO THE EAST. CLOUDS SHOULD THEN DECREASE MONDAY NIGHT WITH DECENT UPPER RIDGING AS SYSTEM MOVES SOUTHEAST AWAY FROM AREA. THE TUESDAY THROUGH FRIDAY EXTENDED PERIOD LOOKS DRY AND MILD. NOT REAL WARM AS RIDGING DOES NOT SEEM TO GET STRONG ENOUGH FAR ENOUGH NORTH TO BRING THE WARM AIR INTO SD...THOUGH IT IS POSSIBLE THAT OUR FORECAST OF 50S MAY NOT BE WARM ENOUGH LATE IN THE WEEK DEPENDING ON HOW STRING THE RIDGING TURNS OUT TO BE AHEAD OF MAJOR TROF APPROACHING FROM THE WEST NEXT WEEKEND. && .AVIATION.../FOR THE 12Z TAFS/ STRATUS EXPECTED TO PERSIST MUCH OF THE DAY TODAY...ESPECIALLY IN AREAS NORTH OF INTERSTATE 90 WHERE MVFR RANGE CEILINGS ALSO MORE LIKELY. THIS INCLUDES KHON TAF LOCATION WHERE MVFR CONDITIONS ARE EXPECTED THROUGH MIDDAY BEFORE LOWEST OF CLOUDS START TO BREAK UP A BIT AND SHIFT EAST. MVFR CONDITIONS MAY NOT COMPLETELY CLEAR OUT OF NORTHEAST 1/3 OF THE CWA THIS AFTERNOON...BUT EVEN IF THEY DO EXPECT ADDITIONAL MVFR CEILINGS TO DROP BACK INTO SOUTHWEST MN/LOCATIONS NORTHEAST OF KBKX-KSPW LINE AFTER 04/00Z. AT THIS TIME EXPECT MVFR CEILINGS TO REMAIN NORTH OF KFSD AND WILL KEEP TAF VFR FOR NOW. HOWEVER WILL BE CLOSE AND WILL HAVE TO WATCH FOR POSSIBLE BROKEN MVFR CEILINGS 14Z-19Z TIME FRAME TODAY. && .FSD WATCHES/WARNINGS/ADVISORIES... SD...NONE. MN...NONE. IA...NONE. NE...NONE. && $$
AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA
NWS SIOUX FALLS SD
325 AM CDT SAT NOV 3 2012 .DISCUSSION.../ISSUED ATY 325 AM CDT/ MULTIPLE CLOUD LAYERS FROM SC TO AC WILL BE PASSING OVER MOST OF THE FORECAST AREA TODAY WITH ONLY THE FAR SOUTHWEST CORNER HAVING HOPE FOR SOME DECENT SUNSHINE. SOME OF THE LOWER DECKS MAY TEND TO BREAK UP LATER IN THE DAY BUT HIGHER AC SEEN ON LATEST IMAGERY IS PINNED BY MODELS TO PASS OVER OUR SOUTHERN AREA. MEANWHILE...RUC INDICATED SOME LIFT WITH THE CURRENT MID DECK WHICH SEEMS RESPONSIBLE FOR THE FEW SPRINKLES MOVING ACROSS OUR NORTH. GOING BY RUC AND OTHER MODELS LACK OF LIFT DURING THE DAY...WILL NOT EXTEND THOSE SPRINKLES PAST 12Z/7 AM CDT RIGHT NOW. ALL THE CLOUDS WILL HAVE THE EXPECTED DAMPENING OF HIGH TEMPERATURES WHICH SHOULD AGAIN BE LOWER THAN GUIDANCE. NOT A BAD DAY THOUGH WITH WINDS LIKELY HOLDING TO LESS THAN 10 MPH. PERHAPS LATE IN THE DAY OR THIS EVENING SKIES OVERALL WILL PARTIALLY CLEAR OVER THE SOUTHWEST HALF OF OUR FORECAST AREA. WILL KEEP A SLIGHT CHANCE OF LIGHT RAIN OR SNOW NORTHEAST CORNER FOR THIS EVENING AS THE GFS DEPICTION OF MID LEVEL MOISTURE AND A LITTLE LIFT FITS OUR EARLIER FORECAST OF THIS. THE DECREASE IN CLOUDS MAY EXTEND INTO OUR EASTERN/NORTHEASTERN AREA EARLY SUNDAY EVEN AS CLOUDS FROM DIGGING UPPER WAVE START TO INCREASE AGAIN FROM THE WEST. NAM IS THE OBVIOUS OUTLIER ON THE BEHAVIOR OF THIS SYSTEM AND WILL GO FOR THE DIGGING NATURE OF SYSTEM INDICATED BY THE GFS...EC...AND EVEN THE PLACID CANADIAN. THIS MEANS KEEPING THE THREAT OF RAIN INCREASING FROM THE WEST SUNDAY AFTERNOON...AND KEEPING LIKELY RAIN THREAT OVER MUCH OF THE AREA SUNDAY NIGHT. WILL KEEP A VERY MINIMAL MENTION OF A LITTLE WET SNOW POSSIBLY MIXED IN NEAR/WEST OF THE JAMES VALLEY LATE SUNDAY NIGHT BUT NO ACCUMULATION. ASSUMING MOST MODELS HAVE THE DIGGING NATURE OF THE SYSTEM PEGGED...EXPECT A LITTLE LINGERING LIGHT RAIN CHANCE MONDAY DECREASING TO THE EAST. CLOUDS SHOULD THEN DECREASE MONDAY NIGHT WITH DECENT UPPER RIDGING AS SYSTEM MOVES SOUTHEAST AWAY FROM AREA. THE TUESDAY THROUGH FRIDAY EXTENDED PERIOD LOOKS DRY AND MILD. NOT REAL WARM AS RIDGING DOES NOT SEEM TO GET STRONG ENOUGH FAR ENOUGH NORTH TO BRING THE WARM AIR INTO SD...THOUGH IT IS POSSIBLE THAT OUR FORECAST OF 50S MAY NOT BE WARM ENOUGH LATE IN THE WEEK DEPENDING ON HOW STRING THE RIDGING TURNS OUT TO BE AHEAD OF MAJOR TROF APPROACHING FROM THE WEST NEXT WEEKEND. && .AVIATION.../FOR THE 06Z TAFS/ ROTTEN STRATUS WILL MOVE THROUGH THE REGION OVERNIGHT AND CONTINUE TO PLAGUE THE AREA MUCH OF THE DAY ON SATURDAY. STRATUS WILL BE MOST PERSISTENT IN THE NORTH...AND MAY DIP INTO THE MVFR RANGE TEMPORARILY. MVFR CEILINGS WILL BE MORE PERSISTENT AT THE KHON TERMINAL...BUT SHOULD GRADUALLY RAISE DURING THE DAY. LIGHT WINDS WILL TRANSITION TO WESTERLY FLOW...THEN TAKE ON A NORTHEAST FLAVOR SATURDAY EVENING BUT REMAIN LIGHT. && .FSD WATCHES/WARNINGS/ADVISORIES... SD...NONE. MN...NONE. IA...NONE. NE...NONE. && $$
AREA FORECAST DISCUSSION
NWS SPOKANE WA
1128 AM PDT Sat Nov 3 2012 .SYNOPSIS... A moist westerly flow will result in periods of rain mainly in the mountains and portions of Eastern Washington through the middle of next week. The Columbia Basin will stay generally dry. Much cooler and unsettled weather will likely arrive by the end of the week. Temperatures will likely be cold enough that most of the precipitation will fall as snow. && .DISCUSSION... Update: Precipitation chances have been increased for the remainder of today across Northeast Washington and North Idaho. None of the models including the HRRR are handling the band of showers over Eastern Washington and North Idaho well this morning. This area of precipitation has been associated with a pocket of mid level instability in the atmosphere as noted by 700-500 theta-e lapse rates near 0 C/KM. As the day progresses models show an increasingly stable environment but with an increase in moisture and isentropic ascent over Northeast Washington and North Idaho. Water vapor satellite shows a very moist zonal flow aimed at Washington and North Idaho so wet conditions will continue into the afternoon. Meanwhile downslope flow off the Cascades will shadow out the Wenatchee and Omak areas with most of the rain confined to near the Cascade crest. JW && .AVIATION... 18Z TAFS: A moist zonal flow will keep areas of -RA over Northeast Washington and North Idaho through 18z Sunday. Meanwhile a very moist boundary layer will result in stratus over most of the area. All models are not handling the current situation well so overall low confidence regarding CIGS over the next 24 hours. But in general MVFR and IFR conditions will be common through the next 24 hours at KGEG/KSFF/KCOE with gradually lowering CIGS expected as the boundary layer continues to moisten. Very low confidence for KEAT/KMWH TAFS through tonight as a continued moist boundary layer could allow fog or stratus to form or expand in coverage...especially tonight. However with an abundance of mid level clouds reducing radiational cooling potential tonight kept prevailing conditions VFR. JW && .PRELIMINARY POINT TEMPS/POPS... Spokane 50 44 56 45 60 43 / 100 20 20 10 10 10 Coeur d`Alene 50 43 56 44 60 42 / 100 30 20 10 10 10 Pullman 57 45 57 46 61 44 / 50 10 20 10 10 10 Lewiston 60 47 61 48 66 48 / 10 0 20 0 10 0 Colville 51 43 57 42 60 40 / 70 30 40 20 10 10 Sandpoint 48 44 54 41 58 40 / 100 70 50 20 20 10 Kellogg 47 42 50 43 56 41 / 80 50 30 20 30 10 Moses Lake 55 45 61 45 62 42 / 10 0 10 0 0 0 Wenatchee 55 48 61 46 61 43 / 0 0 10 10 10 10 Omak 53 44 59 43 60 40 / 20 10 20 20 10 10 && .OTX WATCHES/WARNINGS/ADVISORIES... ID...None. WA...None. && $$
AREA FORECAST DISCUSSION
NWS SPOKANE WA
1049 PM PDT Fri Nov 2 2012 .SYNOPSIS... A drying and warming trend will slowly return to much of the Columbia Basin courtesy of a strengthening ridge of high pressure. Weak systems brushing the ridge will bring some light rain at times to the Cascades and mountains near the Canadian border. Much cooler and unsettled weather will likely arrive by the end of the week. Temperatures will likely be cold enough that most of the precipitation will fall as snow. && .DISCUSSION... Update: forecast update sent to increase PoPs and coverage from the west through the rest of the night. Regional radar trends show a modest band of precipitation from northwest Washington to north- central Oregon. Some of the heavier precipitation has been found west of Yakima, at least in terms of the reflectivity signal. Latest HRRR runs and radar extrapolation brings this precipitation into the western CWA between 03-06Z (8 PM to 11 PM) and eastward through the remainder of the night. The quandary: how well will it hold together as it moves off the higher terrain? I expect it will weaken some, limiting how much actually is capable of being measured/reaching the ground. However the radar returns warrant at least adding scattered to isolated showers across the Basin this evening, expanding through Spokane area and Palouse late tonight into the overnight in isolated fashion. I added some fog near the Cascades and the Basin Saturday morning, where some cloud breaks are possible late in the overnight. With incoming mid and high clouds determining coverage and intensity and duration of any fog will be difficult. As such I left it as only patchy fog. /J. Cote` && .AVIATION... 06Z TAFS: A weak upper wave moves across the region, with a threat of isolated showers in the vcnty of TAF sites, with the threat moving primarily to the eastern TAFs during the day Saturday. Tonight a thickening and lowering of clouds is expected. VFR and occasional MVFR conditions are expected. Toward morning, the light east to southeast winds will bring a threat of some IFR stratus near KGEG and again near KMWH and KEAT, along with some patchy fog. Confidence remains low, due to the passing mid and high clouds that may inhibit such development. Some drier air coming in above the surface near sunrise near KEAT/KMWH will allow a better threat of said IFR stratus to develop. Conditions improve through the late morning and afternoon, with more mid and high clouds streaming in ahead of the next weak wave. /J. Cote` && .PRELIMINARY POINT TEMPS/POPS... Spokane 42 55 44 56 45 59 / 20 20 20 20 10 10 Coeur d`Alene 41 54 43 56 44 58 / 20 30 30 20 10 10 Pullman 44 58 45 57 46 62 / 20 20 10 20 10 0 Lewiston 44 60 47 61 48 64 / 20 10 10 20 0 0 Colville 44 54 43 57 43 61 / 30 40 40 40 20 20 Sandpoint 42 52 44 54 41 58 / 20 50 60 50 20 20 Kellogg 38 47 42 50 43 55 / 20 30 30 30 10 20 Moses Lake 42 58 45 61 45 60 / 50 10 10 10 0 0 Wenatchee 44 55 48 61 46 59 / 50 10 10 10 10 10 Omak 45 55 44 59 43 59 / 50 20 20 20 10 10 && .OTX WATCHES/WARNINGS/ADVISORIES... ID...None. WA...None. && $$
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
545 PM CDT SAT NOV 3 2012 .SHORT TERM...TONIGHT THROUGH TUESDAY 258 PM CDT SAT NOV 3 2012 THE MAIN FOCUS GOING INTO THE EARLY PART OF NEXT WEEK IS WITH THE PERIODIC CHANCES FOR PRECIPITATION AND WHAT TYPE THEY WILL BE AS THEY REACH THE GROUND...PARTICULARLY TONIGHT. CURRENTLY...A CLOSED MID LEVEL LOW IS SLOWLY PROPAGATING TO THE SOUTHEAST NEAR THE INTERSECTION OF NORTH DAKOTA/SOUTH DAKOTA/MINNESOTA PER SATELLITE AND 03.18Z RAP ANALYSIS. A LEAD SHORT WAVE TROUGH EXTENDS TO THE EAST OUT OF THIS LOW AND HAS BEEN THE FOCUS FOR SOME LIGHT RAIN/SNOW SHOWERS ACROSS CENTRAL MINNESOTA ON INTO NORTHERN WISCONSIN THIS MORNING AND AFTERNOON. AT THE SURFACE...A LOW PRESSURE SYSTEM IS MOVING INTO WESTERN TENNESSEE WITH AN INVERTED TROUGH EXTENDING NORTHWEST FROM THE LOW ACROSS IOWA ON INTO A WEAKER SURFACE LOW IN FAR SOUTHEAST NORTH DAKOTA. THIS SURFACE LOW WILL TRACK TO THE SOUTHEAST TONIGHT AS THE CLOSED MID LEVEL LOW DROPS SOUTHEAST AS WELL AND WILL BE THE FOCUS FOR PRECIPITATION CHANCES OVERNIGHT. PLENTY OF MID LEVEL SUPPORT COMING DOWN WITH THIS CLOSED LOW TONIGHT WITH THE 03.12Z GFS/NAM SHOWING STRONG 500-300MB PV ADVECTION AND QG FORCING DROPPING THROUGH SOUTH CENTRAL MINNESOTA AND NORTHEAST IOWA BETWEEN 3-12Z TONIGHT. THE MAIN ISSUE IS IN THE LOW LEVELS WHERE THERE IS LITTLE TO NO FRONTOGENESIS OR ISENTROPIC LIFT TO HELP DEEPEN THE LIFT AND SATURATION. CROSS SECTIONS/TIME HEIGHT PROFILES SHOW A QUICK SHOT OF DECENT MID LEVEL OMEGA COMING THROUGH WITH THIS TROUGH OVERNIGHT WITH 03.12Z GFS/NAM FORECAST SOUNDINGS ALSO SHOWING A BRIEF PERIOD OF SATURATING BETWEEN 850-400MB CENTERED AROUND 6-9Z. WHILE PRECIPITATION WILL BE ON THE LIGHT SIDE HAVE DECIDED TO PUT SOME PRECIPITATION CHANCES IN FOR SOUTHEAST MINNESOTA AND NORTHEAST IOWA OVERNIGHT. PRECIPITATION TYPE IS STILL A BIT OF A QUESTION DUE TO THE LOW LEVEL WARM LAYER MAX TEMPERATURES BEING UP AROUND 3-4C PER 03.12Z NAM/GFS AND 03.18Z RAP SOUNDINGS THOUGH THEY COOL AS THE PRECIPITATION LINGERS WITH ABOUT A 1KFT NEAR SURFACE LAYER THAT IS UP TO 1C. EXPECT THAT MOST OF THE PRECIPITATION WILL FALL AS LIGHT RAIN THOUGH WITH THE WET BULB TEMPERATURES HANG AROUND FREEZING THERE COULD BE SOME SNOW THAT MIXES IN. WITH SURFACE TEMPERATURES AT OR AROUND 34-38 AND WARM ROAD TEMPERATURES...ANY LIGHT SNOW ACCUMULATIONS OF A TRACE TO A TENTH OF AN INCH WOULD JUST BE ON GRASSY SURFACES. SUBSIDENCE MOVES IN ON THE BACK SIDE OF THIS LOW AND WILL PROVIDE FOR A DRY YET COOL SUNDAY WITH A RIDGE OF SURFACE HIGH PRESSURE EXTENDING SOUTH OUT OF CANADA THROUGH THE WESTERN GREAT LAKES. THE NEXT TROUGH WILL DIVE DOWN THROUGH THE NORTHWEST FLOW ALOFT SUNDAY NIGHT INTO MONDAY MORNING ACROSS THE CENTRAL PLAINS. THE MAIN FORCING AND DEEP MOISTURE FOR THIS SYSTEM APPEARS TO BE STAYING TO THE WEST OF THE FORECAST AREA WITH THE EASTERN PERIPHERY OF IT GETTING INTO SOUTHEAST MINNESOTA AND NORTHEAST IOWA. THE 03.12Z NAM APPEARS TO BE AN OUTLIER AND BRINGS THE SYSTEM THROUGH WITH A SURFACE INVERTED TROUGH EXTENDING UP ACROSS MUCH OF THE REGION. WITH ALL OF THE OTHER GUIDANCE KEEPING THE FORCING/PRECIPITATION TO THE SOUTHWEST INTO MONDAY...HAVE OPTED TO GO WITH THAT ROUTE THAN WITH THE WETTER NAM SOLUTION. THE BEST CHANCES FOR MORE WIDESPREAD PRECIPITATION COME IN ON TUESDAY AS ANOTHER MID LEVEL SHORTWAVE TROUGH DIVES DOWN FROM CANADA ALONG WITH A SURFACE LOW AND COLD FRONT. THIS SHOULD BRING DEEP ENOUGH OF FORCING/MOISTURE WITH IT TO PRODUCE SOME PRECIPITATION WITH IT AS IT COMES THROUGH. 03.12Z GFS/NAM THERMAL PROFILES LOOK WARM ENOUGH FOR PRECIPITATION TYPE TO BE ALL RAIN...SO HAVE REMOVED THE MIX FOR MONDAY NIGHT INTO TUESDAY. .LONG TERM...TUESDAY NIGHT THROUGH SATURDAY 258 PM CDT SAT NOV 3 2012 AFTER THE SYSTEM MOVES THROUGH ON TUESDAY THE PATTERN SHIFTS WITH THE UPPER LEVEL TROUGH MOVING TOWARD THE EAST COAST WITH AN AMPLIFYING RIDGE SPREADING ACROSS THE NORTHERN PLAINS. THIS WILL LEAD TO DRY AND COOL CONDITIONS WITH A GRADUAL WARMING TREND GOING INTO NEXT WEEKEND AS THE RIDGE SHIFTS EAST AND SOUTHWESTERLY FLOW KICKS IN ALOFT. AS THE RIDGE GOES EAST A DEEP TROUGH WILL CARVE ITS WAY SOUTHEAST ACROSS THE ROCKIES INTO SATURDAY. SOME DIFFERENCES ARISE BETWEEN THE 03.12Z GFS AND ECMWF WITH THE GFS BEING FASTER AND DEEPER WITH THE CORE OF THE NORTHERN PORTION OF THE TROUGH WHILE THE ECMWF KEEPS IT FURTHER WEST. HAVE KEPT A BLEND OF THE FORECASTS GOING...BUT IF THE ECMWF PANS OUT IT WILL BE WARMER AND DRIER THAN CURRENTLY ADVERTISED WITH THE UPPER MISSISSIPPI RIVER VALLEY IN THE WARM SECTOR THROUGH SATURDAY WHILE THE GFS HAS STRONG LOW LEVEL MOISTURE ADVECTION OUT OF THE GULF PRODUCING PRECIPITATION AHEAD OF A COLD FRONT SATURDAY. && .AVIATION... 545 PM CDT SAT NOV 3 2012 MVFR CIGS ARE BECOMING MORE LIKELY...BASED ON LATEST SATELLITE TRENDS...SFC OBS...AND RH FORECASTS/BUFKIT SOUNDINGS VIA THE RAP13/NAM12. AN UPPER LEVEL SHORTWAVE TROUGH WILL DRIVE SOUTHEAST FROM THE NORTHERN PLAINS TO ACROSS NORTHERN ILL BY 18Z SUN. SATURATION INCREASES IN THE VERTICAL AS THE SHORTWAVE APPROACHES...WITH SOUNDINGS FAVORING SUB 3 KFT CIGS AFTER 06Z AT KRST...AND TOWARD 12Z FOR KLSE. DAYTIME MIXING SHOULD PUSH CIG HEIGHTS UP DURING THE DAY ON SUN. THAT SAID...ANOTHER SHORTWAVE TROUGH WILL PUSH ACROSS THE REGION FOR LATE SUN NIGHT/MONDAY. SATURATION IS DEEPER AND MORE WIDESPREAD WITH THIS FEATURE...AND A PROLONGED PERIOD OF MVFR CIGS - OR CLOSE TO IT - LOOKS LIKELY FOR MONDAY. AS FOR PCPN...SOME QG CONVERGENCE WITH THE SHORTWAVE...AND HINTS OF FRONTOGENETIC FORCING. LATEST 88-D IMAGERY AND SFC OBS ALSO INDICATE SOME LIGHT PCPN OVER SD/ND ASSOCIATED WITH THE SHORTWAVE. THE NAM12 SLIDES LIGHT QPF ACROSS SOUTHERN MN/NORTHEAST IA OVERNIGHT...AS DOES THE LATEST HRRR. TRENDS FAVOR KEEPING ANY PCPN CHANCES SOUTHWEST OF KLSE...BUT KRST COULD GET SOME SPRINKLES/FLURRIES. WILL ADD A MENTION INTO THE TAF FORECAST...BUT DON/T EXPECT AN IMPACT TO VSBYS OR ACCUMULATIONS. && .ARX WATCHES/WARNINGS/ADVISORIES... 258 PM CDT SAT NOV 3 2012 WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...HALBACH LONG TERM....HALBACH AVIATION.....RIECK
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
258 PM CDT SAT NOV 3 2012 .SHORT TERM...TONIGHT THROUGH TUESDAY 258 PM CDT SAT NOV 3 2012 THE MAIN FOCUS GOING INTO THE EARLY PART OF NEXT WEEK IS WITH THE PERIODIC CHANCES FOR PRECIPITATION AND WHAT TYPE THEY WILL BE AS THEY REACH THE GROUND...PARTICULARLY TONIGHT. CURRENTLY...A CLOSED MID LEVEL LOW IS SLOWLY PROPAGATING TO THE SOUTHEAST NEAR THE INTERSECTION OF NORTH DAKOTA/SOUTH DAKOTA/MINNESOTA PER SATELLITE AND 03.18Z RAP ANALYSIS. A LEAD SHORT WAVE TROUGH EXTENDS TO THE EAST OUT OF THIS LOW AND HAS BEEN THE FOCUS FOR SOME LIGHT RAIN/SNOW SHOWERS ACROSS CENTRAL MINNESOTA ON INTO NORTHERN WISCONSIN THIS MORNING AND AFTERNOON. AT THE SURFACE...A LOW PRESSURE SYSTEM IS MOVING INTO WESTERN TENNESSEE WITH AN INVERTED TROUGH EXTENDING NORTHWEST FROM THE LOW ACROSS IOWA ON INTO A WEAKER SURFACE LOW IN FAR SOUTHEAST NORTH DAKOTA. THIS SURFACE LOW WILL TRACK TO THE SOUTHEAST TONIGHT AS THE CLOSED MID LEVEL LOW DROPS SOUTHEAST AS WELL AND WILL BE THE FOCUS FOR PRECIPITATION CHANCES OVERNIGHT. PLENTY OF MID LEVEL SUPPORT COMING DOWN WITH THIS CLOSED LOW TONIGHT WITH THE 03.12Z GFS/NAM SHOWING STRONG 500-300MB PV ADVECTION AND QG FORCING DROPPING THROUGH SOUTH CENTRAL MINNESOTA AND NORTHEAST IOWA BETWEEN 3-12Z TONIGHT. THE MAIN ISSUE IS IN THE LOW LEVELS WHERE THERE IS LITTLE TO NO FRONTOGENESIS OR ISENTROPIC LIFT TO HELP DEEPEN THE LIFT AND SATURATION. CROSS SECTIONS/TIME HEIGHT PROFILES SHOW A QUICK SHOT OF DECENT MID LEVEL OMEGA COMING THROUGH WITH THIS TROUGH OVERNIGHT WITH 03.12Z GFS/NAM FORECAST SOUNDINGS ALSO SHOWING A BRIEF PERIOD OF SATURATING BETWEEN 850-400MB CENTERED AROUND 6-9Z. WHILE PRECIPITATION WILL BE ON THE LIGHT SIDE HAVE DECIDED TO PUT SOME PRECIPITATION CHANCES IN FOR SOUTHEAST MINNESOTA AND NORTHEAST IOWA OVERNIGHT. PRECIPITATION TYPE IS STILL A BIT OF A QUESTION DUE TO THE LOW LEVEL WARM LAYER MAX TEMPERATURES BEING UP AROUND 3-4C PER 03.12Z NAM/GFS AND 03.18Z RAP SOUNDINGS THOUGH THEY COOL AS THE PRECIPITATION LINGERS WITH ABOUT A 1KFT NEAR SURFACE LAYER THAT IS UP TO 1C. EXPECT THAT MOST OF THE PRECIPITATION WILL FALL AS LIGHT RAIN THOUGH WITH THE WET BULB TEMPERATURES HANG AROUND FREEZING THERE COULD BE SOME SNOW THAT MIXES IN. WITH SURFACE TEMPERATURES AT OR AROUND 34-38 AND WARM ROAD TEMPERATURES...ANY LIGHT SNOW ACCUMULATIONS OF A TRACE TO A TENTH OF AN INCH WOULD JUST BE ON GRASSY SURFACES. SUBSIDENCE MOVES IN ON THE BACK SIDE OF THIS LOW AND WILL PROVIDE FOR A DRY YET COOL SUNDAY WITH A RIDGE OF SURFACE HIGH PRESSURE EXTENDING SOUTH OUT OF CANADA THROUGH THE WESTERN GREAT LAKES. THE NEXT TROUGH WILL DIVE DOWN THROUGH THE NORTHWEST FLOW ALOFT SUNDAY NIGHT INTO MONDAY MORNING ACROSS THE CENTRAL PLAINS. THE MAIN FORCING AND DEEP MOISTURE FOR THIS SYSTEM APPEARS TO BE STAYING TO THE WEST OF THE FORECAST AREA WITH THE EASTERN PERIPHERY OF IT GETTING INTO SOUTHEAST MINNESOTA AND NORTHEAST IOWA. THE 03.12Z NAM APPEARS TO BE AN OUTLIER AND BRINGS THE SYSTEM THROUGH WITH A SURFACE INVERTED TROUGH EXTENDING UP ACROSS MUCH OF THE REGION. WITH ALL OF THE OTHER GUIDANCE KEEPING THE FORCING/PRECIPITATION TO THE SOUTHWEST INTO MONDAY...HAVE OPTED TO GO WITH THAT ROUTE THAN WITH THE WETTER NAM SOLUTION. THE BEST CHANCES FOR MORE WIDESPREAD PRECIPITATION COME IN ON TUESDAY AS ANOTHER MID LEVEL SHORTWAVE TROUGH DIVES DOWN FROM CANADA ALONG WITH A SURFACE LOW AND COLD FRONT. THIS SHOULD BRING DEEP ENOUGH OF FORCING/MOISTURE WITH IT TO PRODUCE SOME PRECIPITATION WITH IT AS IT COMES THROUGH. 03.12Z GFS/NAM THERMAL PROFILES LOOK WARM ENOUGH FOR PRECIPITATION TYPE TO BE ALL RAIN...SO HAVE REMOVED THE MIX FOR MONDAY NIGHT INTO TUESDAY. .LONG TERM...TUESDAY NIGHT THROUGH SATURDAY 258 PM CDT SAT NOV 3 2012 AFTER THE SYSTEM MOVES THROUGH ON TUESDAY THE PATTERN SHIFTS WITH THE UPPER LEVEL TROUGH MOVING TOWARD THE EAST COAST WITH AN AMPLIFYING RIDGE SPREADING ACROSS THE NORTHERN PLAINS. THIS WILL LEAD TO DRY AND COOL CONDITIONS WITH A GRADUAL WARMING TREND GOING INTO NEXT WEEKEND AS THE RIDGE SHIFTS EAST AND SOUTHWESTERLY FLOW KICKS IN ALOFT. AS THE RIDGE GOES EAST A DEEP TROUGH WILL CARVE ITS WAY SOUTHEAST ACROSS THE ROCKIES INTO SATURDAY. SOME DIFFERENCES ARISE BETWEEN THE 03.12Z GFS AND ECMWF WITH THE GFS BEING FASTER AND DEEPER WITH THE CORE OF THE NORTHERN PORTION OF THE TROUGH WHILE THE ECMWF KEEPS IT FURTHER WEST. HAVE KEPT A BLEND OF THE FORECASTS GOING...BUT IF THE ECMWF PANS OUT IT WILL BE WARMER AND DRIER THAN CURRENTLY ADVERTISED WITH THE UPPER MISSISSIPPI RIVER VALLEY IN THE WARM SECTOR THROUGH SATURDAY WHILE THE GFS HAS STRONG LOW LEVEL MOISTURE ADVECTION OUT OF THE GULF PRODUCING PRECIPITATION AHEAD OF A COLD FRONT SATURDAY. && .AVIATION...THROUGH 18Z SUNDAY 1233 PM CDT SAT NOV 3 2012 VFR CONDITIONS ARE EXPECTED AT THE TAF SITES THROUGH THIS EVENING. AN UPPER LEVEL LOW PRESSURE SYSTEM WILL BRING BKN TO OVC SKIES TO THE AREA TODAY INTO TONIGHT AS IT MOVES INTO THE REGION FROM THE NORTHERN PLAINS. CLOUD BASES THIS AFTERNOON WILL RANGE FROM 8 TO 11 KFT...THEN GRADUALLY LOWER TO AROUND 3 TO 4 KFT LATE THIS EVENING INTO THE OVERNIGHT HOURS AS THE UPPER LOW MOVES IN. HAVE NOT INCLUDED ANY LIGHT RAIN OR SNOW ACTIVITY AT THE TAF SITES AT THIS TIME...BUT WILL HAVE TO KEEP A CLOSE WATCH ON THIS POTENTIAL OVERNIGHT TONIGHT AS THE MAIN TROUGH AXIS PASSES OVER THE AREA. STRONGER FORCING APPEARS TO BE ACROSS CENTRAL IOWA SO THINKING ANY PRECIPITATION WOULD MOST LIKELY FALL AS SPRINKLES OR FLURRIES. MVFR CONDITIONS ARE POSSIBLE OVERNIGHT TONIGHT...AND FORECAST SOUNDINGS SUPPORT THIS AS WELL AS CURRENT OBSERVATIONS ACROSS WESTERN MINNESOTA INTO THE EASTERN DAKOTAS. HAVE LOWERED CLOUD BASES TO 3500 FT AT KLSE STARTING AT 10Z TONIGHT...AND LOWERED CLOUD BASES AT KRST TO 3000 FT STARTING AT 09Z. WINDS WILL BE LIGHT THROUGH THE FORECAST PERIOD RANGING FROM SOUTHEAST TO SOUTHWEST AT 4 TO 6 KTS. && .ARX WATCHES/WARNINGS/ADVISORIES... 258 PM CDT SAT NOV 3 2012 WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...HALBACH LONG TERM...HALBACH AVIATION.....WETENKAMP
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
300 AM EST MON NOV 5 2012 .SHORT TERM /TODAY THROUGH TUESDAY/... /ISSUED AT 223 PM EST SUN NOV 4 2012/ LATEST RAP ANALYSIS OVER THE LOCAL AREA SHOWS SURFACE BASED CAPE HAS INCREASED TO BETWEEN 500 J/KG AND 750 J/KG OVER THE SOUTHERN TIER WITH MIXED CAPE VALUES CONSIDERABLY LOWER. BAND OF PRE- FRONTAL -RA CONTINUES TO MAKE STEADY PROGRESS INTO NORTH CENTRAL GEORGIA BUT NO CONVECTIVE ELEMENTS OF NOTE WITH THIS ACTIVITY THUS FAR. INTO THE BETTER INSTABILITY HOWEVER...STARTING TO SEE SOME MORE ORGANIZED ACTIVITY. HOWEVER...FEEL BY THE TIME STRONG OR SEVERE COULD BE REALIZED...BEST LIFT WILL HAVE SHIFTED EAST OUT OF THE AREA THIS EVENING. WILL LIKELY SCALE BACK THE HWO AND ONGOING GRAPHICAST ONCE DEVELOPING LINE SHIFTS EAST. MONDAY LOOKS TO BE THE ONLY SHORT TERM DAY WITH FAIRLY BENIGN CONDITIONS AS HIGH CENTERED OVER CANADA HAS ENOUGH WEAK RIDGING SOUTH INTO THE OUR AREA TO PRODUCE A POP FREE DAY. CLOUDS HOWEVER WILL BECOME PLENTIFUL DURING THE DAY HAS MID AND HIGH LEVEL MOISTURE MAKES A RAPID RETURN TO THE NORTHWEST HALF OF THE REGION. THESE CLOUDS WILL PLAY AN IMPORTANT ROLE AS THEIR ARRIVAL PRIOR TO SUNSET WILL RESULT IN MINS TUESDAY MORNING NOT REACHING THEIR FULL POTENTIAL. THIS WILL BE CRUCIAL AS PRECIP BEGINS TO OVERSPREAD THE AREA IN EARNEST JUST PRIOR TO DAYBREAK TUESDAY AS CLOSED UPPER LOW ROTATES THROUGH THE DEEP SOUTH. NAM12 IS BY FAR THE MOST AGGRESSIVE IN DYNAMICALLY COOLING THE COLUMN...TAKING THE 850MB TEMP FROM +2C TO -1C IN A MATTER OF TWO HOURS. NOT COMPLETELY OUR OF THE QUESTION WITH SUCH A DYNAMIC SYSTEM TO SEE THIS TYPE OF COOLING ALOFT...BUT JUST CANNOT SEEM TO GET SURFACE TEMPS COLD ENOUGH TO ALLOW ANY FROZEN PRECIP TO REACH THE GROUND. THIS IS TRUE EVEN IN THE MOUNTAINS AND WILL KEEP FORECAST ALL LIQUID THIS RUN BUT WILL NEED TO BE MONITORED CLOSELY WITH SUBSEQUENT CYCLES. AS FAR AS THE THUNDER POTENTIAL...BEST SURFACE INSTABILITY SHOULD REMAIN SOUTH OF THE AREA...BUT GIVEN THE AMOUNT OF ISENTROPIC UPGLIDE JUST NORTH OF THE LOW...WILL NEED TO KEEP ISOLATED THUNDER MENTION FOR THE SOUTHERN TIER. DEESE .LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... /ISSUED AT 223 PM EST SUN NOV 4 2012/ GFS AND ECMWF CONTINUE IN ARE IN FAIRLY DECENT AGREEMENT THROUGH THE EXTENDED...AND FOR THE MOST PART AFTER THE SYSTEM EXITS TUESDAY NIGHT THE EXTENDED SHOULD BE DRY WITH A GRADUAL WARMING TREND AS THE MIDLEVEL RIDGE BUILDS IN FROM THE GULF. CORRESPONDING SURFACE HIGH PRESSURE PUSHES THROUGH THE SOUTHEAST THURSDAY INTO FRIDAY...ANCHORING ITSELF IN THE WESTERN ATLANTIC BY SATURDAY BUT WITH STRONG RIDGING REMAINING IN PLACE. HAVE MADE NO SUBSTANTIVE CHANGES TO THE EXTENDED AT THIS TIME. TDP PREV DISCUSSION... /ISSUED 326 AM EST SUN NOV 4 2012/ BIG FORECAST STORY THROUGH THE EXTENDED IS LOW PRESSURE SYSTEM IMPACTING THE AREA TUESDAY THROUGH WEDNESDAY. MODELS CONTINUE TO SUGGEST DEEPENING OF THE LOW OVER THE SOUTHERN ALABAMA AND THE FLORIDA PANHANDLE TUESDAY MORNING THROUGH EARLY AFTERNOON. AS A RESULT OF THE PROJECTED TRACK...EXPECT BEST RAIN CHANGES TO INITIALLY BE ACROSS WESTERN GA LATE ON MONDAY INTO EARLY MORNING TUESDAY...THEN TRANSITIONING TO THE SOUTHERN 2/3 OF THE FORECAST AREA BY TUESDAY MORNING. PREVIOUS MODEL RUNS HAD SUGGESTED MORE ORGANIZED DEVELOPMENT TO OUR SOUTH IN THE FORM OF A SQUALL...CUTTING OFF THE AREA FROM MOISTURE SOURCE...BUT HAVE OPTED TO INCREASE POPS CONSIDERABLY DUE TO THE AGREEMENT WITH THE LATEST MODEL RUNS OF THE NORTHERN MOISTURE PROGRESSION. LITTLE OVERALL INSTABILITY WITH THIS SYSTEM HAS LIMITED THE MENTION OF THUNDER IN THE FORECAST...THOUGH DID KEEP MENTION OF ISOLATED CONVECTION IN THE FAR SE CWA TUESDAY LATE MORNING THROUGH EARLY AFTERNOON. CENTER OF THE SURFACE LOW TRACKS ACROSS NORTHERN FLORIDA INTO TUESDAY NIGHT...AND EMERGES OFF THE GEORGIA AND CAROLINA COASTS BY WEDNESDAY MORNING. HIGH PRESSURE BUILDS IN BEHIND THE LOW AND ASSOCIATED FRONT...KEEPING THE REMAINDER OF THE LONG TERM FORECAST DRY. COOLER TEMPERATURES IN THE MIDDLE OF THE WEEK WILL GRADUALLY WARM BY THE WEEKEND. 31 && AVIATION... 06Z UPDATE... CLEAR SKIES EXPECTED THROUGH 15Z WHEN MORE HIGH CLOUDS...10 THSD FT TO 25 THSD FT SCT TO BKN...START MOVING IN AHEAD OF SYSTEM PUSHING THROUGH MID MISSISSIPPI RIVER VALLEY. VFR CONDITIONS EXPECTED THROUGH 03Z. MVFR CIGS...3 THSD FT TO 4 THSD FT AFTER 04Z AS LIGHT SHRA MOVE IN. VSBYS TO REMAIN VFR THROUGH PERIOD. WINDS NORTHWEST....BECOMING NORTHERLY BY 15Z...AND SHIFTING TO NORTHEAST AROUND 23Z. WINDS 5 TO 10 KTS THROUGH PERIOD. //ATL CONFIDENCE...06Z UPDATE... MEDIUM ON WIND SHIFT MONDAY. HIGH ON REMAINING ELEMENTS. 37 && .PRELIMINARY POINT TEMPS/POPS... ATHENS 74 44 62 42 / 30 5 0 50 ATLANTA 73 43 64 46 / 30 0 0 60 BLAIRSVILLE 63 37 57 40 / 20 0 0 50 CARTERSVILLE 68 38 63 41 / 20 0 0 60 COLUMBUS 79 44 69 48 / 30 20 0 80 GAINESVILLE 69 45 60 44 / 20 0 0 50 MACON 83 43 68 44 / 30 30 0 80 ROME 67 36 64 40 / 20 0 0 60 PEACHTREE CITY 73 37 65 40 / 40 0 0 70 VIDALIA 86 54 68 49 / 30 40 0 70 && .FFC WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
316 AM CST MON NOV 5 2012 .SYNOPSIS... 06Z SFC ANALYSIS HAS A LOW NEAR KFNB WITH A WARM FRONT ALONG THE KS/MO BORDER. A COLD FRONT RAN FROM THE LOW INTO NORTHEAST NEW MEXICO WHILE AN INVERTED TROF RAN FROM THE LOW INTO SOUTHWEST MINNESOTA. DEW POINTS WERE IN THE 20S ACROSS THE GREAT LAKES WITH 30S AND 40S OVER MUCH OF THE PLAINS AND MIDWEST. RADAR HAS WIDESPREAD RAIN AND DRIZZLE WAS ASSOCIATED WITH THE LOW AND INVERTED TROF ACROSS IOWA AND MISSOURI. && .SHORT TERM...TODAY AND TONIGHT... LOW LEVEL EASTERLY FLOW HAS RESULTED IN A WALL OF DRY AIR WHICH HAS STOPPED THE EASTWARD PROGRESSION OF THE PRECIPITATION. THE 850-700MB CONDENSATION PRESSURE DEFICITS IN COMBINATION WITH OVERALL FORCING FROM THE WRF AND RAP DEPICT QUITE WELL THE AREAL COVERAGE OF THE PRECIPITATION. USING THIS AS A GUIDE THE DRY EASTERLY FLOW WILL HELP PUSH THE PRECIPITATION TO THE SOUTH AND WEST DURING THE DAY WITH ONLY LINGERING DZ/RA ACROSS THE SOUTH THIRD BY LATE AFTERNOON. CLOUD COVER/PRECIPITATION WILL HELP HOLD DOWN TEMPERATURES TODAY WITH READINGS IN THE MID/UPPER 40S COMMON. MAINLY DRY CONDITIONS WILL BE SEEN ACROSS THE AREA THIS EVENING AS CONDENSATION PRESSURE DEFICITS REMAIN HIGH. BY LATE TONIGHT CONDENSATION PRESSURE DEFICITS COLLAPSE AGAIN AS THE NEXT SHORTWAVE APPROACHES. LIGHT RAIN/DRIZZLE MAY ENTER BUCHANAN COUNTY JUST PRIOR TO SUNRISE ON TUESDAY WHILE THE REMAINDER OF THE CWFA STAYS DRY. 08 .LONG TERM...TUESDAY THROUGH NEXT SUNDAY... NEXT CLIPPER SYSTEM IS EXPECTED TO TRACK THROUGH THE GREAT LAKES TUE-TUE NGT. MOISTURE IS MARGINAL BUT DYNAMICS IN FORM OF GOOD UPPER DIFFLUENCE... MID LEVEL FRONTOGENESIS AND DIVERGENCE WITH LEFT EXIT REGION OF 100-120+ KT H3 JET MORE THAN ADEQUATE TO OVERCOME AND GENERATE BAND(S) OF LIGHT RAIN OR SHOWERS TUE AM BEFORE SHIFTING EAST. SPEED OF SYSTEM AND MARGINAL MOISTURE SUPPORTS LIGHT AMOUNTS OF A FEW HUNDREDTHS TO AROUND 0.1 INCH MOST AREAS. BANKING ON AT LEAST PARTIAL SUNSHINE W/SW SECTIONS TUE AFTN IN WAKE OF PASSING SYSTEM TO PUSH HIGHS INTO THE 50S... WITH 40S LIKELY ELSEWHERE WITH COOLEST READINGS NORTHEAST CWA. THIS CLIPPER SYSTEM LOOKS TO PHASE WITH THE SYSTEM THAT IS MOVING THROUGH EARLY THIS AM TO PRODUCE CLASSIC NOR`EASTER... WITH STRONG LOW MOVING UP ALONG THE NORTHEAST COAST UNFORTUNATELY POUNDING AREAS RECOVERING FROM HURRICANE SANDY WITH MORE HEAVY PCPN AND STRONG WINDS WED-THU. WED-WED NGT... INCOMING SUBSIDENCE WITH SFC RIDGE BUILDING IN WAKE OF DEPARTING CLIPPER SYSTEM TO PROVIDE DRY WX WITH DECREASING CLOUDS. TEMPS REMAIN BELOW NORMAL WITH HIGHS IN THE 40S TO L50S... AND LOWS IN THE 20S TO L30S. THU-FRI... SFC RIDGE SLIDES EAST EARLY IN THE PERIOD WITH RETURN FLOW DEVELOPING. ALOFT... UPPER RIDGE AMPLIFIES OVERHEAD AND ESPECIALLY JUST DOWNSTREAM OVER THE OHIO VLY IN RESPONSE TO LARGE TROUGH MOVING ACROSS THE WESTERN CONUS. PERSISTENT WARM ADVECTION ON STRENGTHENING LOW-MID LEVEL SOUTHERLY WINDS SUPPORT MODERATING TEMPS NEAR TO ABOVE NORMAL. SAT-SUN... PATTERN SET TO UNDERGO CHANGE LEADING TO UNSETTLED/WET REGIME FOR THE AREA. STILL UNCERTAINTIES WITH MODELS HANDLING OF ENERGY AS IT EJECTS FROM THE WESTERN CONUS... WITH MAIN IMPACTS TO TIMING OF FRONT AND PRECIPITATION. GENERAL CONSENSUS ATTM IS TO MOVE STRONG COLD FRONT THROUGH THE AREA ON SUN WITH WIDESPREAD RAIN OCCURRING MAINLY POST FRONTAL. LOCATION OF JET DOES APPEAR FAVORABLE FOR AT LEAST ISOLD TO SCT STORMS ATTM... BUT BEING LATE DAY 6-7 AND LIKELIHOOD FOR ADDITIONAL CHANGES WITH MODELS HANDLING OF ENERGY HAVE OPTED TO KEEP PTYPE AS SHOWERS FOR NOW. STRENGTH OF FORCING ALONG WITH GULF MOISTURE FEED CONTINUES TO SUPPORT MODERATE TO LOCALLY HEAVY RAINS OF 0.5 TO 1.5 INCHES. COULD BE HIGHER AMOUNTS ESPECIALLY IF WAVE DEVELOPS ON FRONT AS SHOWN BY 00Z GFS. THIS IS SOME OF THE UNCERTAINTY TO BE RESOLVED IN THE COMING DAYS. TEMPS LOOK TO COME CRASHING BACK DOWN TO BELOW NORMAL BY EARLY NEXT WEEK IN WAKE OF STRONG COLD FRONTAL PASSAGE. MCCLURE .AVIATION... /ISSUED 1142 PM CST SUN NOV 4 2012/ THERE IS AN UPPER LEVEL SHORTWAVE DROPPING SOUTH ACROSS IOWA TONIGHT. THIS SHORTWAVE HAS BROUGHT A BAND OF LIGHT RAIN WITH MAINLY MVFR TO VFR CONDITIONS TO EASTERN IOWA...MAINLY AFFECTING KCID AND KBRL. THIS IS EXPECTED TO CONTINUE OVERNIGHT WITH BOTH LOCATIONS EXPERIENCING MVFR CIGS AND VSBYS IN BANDS OF LIGHT RAIN. KMLI LESS AT RISK...BUT MAY ALSO GET THESE CONDITIONS OVERNIGHT. KDBQ IS NOT LIKELY TO BE AFFECTED AT ALL. DRY AIR TO SWEEP BACK INTO THE AREA FROM THE EAST AS THE SHORTWAVE MOVES SOUTH OF THE AREA AND CONDITIONS EXPECTED TO RETURN QUICKLY TO VFR FROM NORTH TO SOUTH DURING THE MID TO LATE MORNING HOURS. EAST TO SOUTHEAST WINDS TO CONTINUE THROUGH THE TAF PERIOD...GENERALLY LESS THAN 10 KTS. LE && .DVN WATCHES/WARNINGS/ADVISORIES... IA...NONE. IL...NONE. MO...NONE. && $$ 08/MCCLURE/LE
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1115 PM CST SUN NOV 4 2012 .UPDATE... ISSUED AT 933 PM CST SUN NOV 4 2012 INHERITED FCST STILL LOOKS GOOD...SO NO MAJOR CHANGES THIS EVENING. LGHT RAIN/SPRINKLES HAVE BEEN OCCURRING THIS EVENING...MOSTLY ACROSS OUR IL COUNTIES. STILL WAITING ON THE POTENT UPPER LEVEL SYSTEM COMING OUT OF THE PLAINS THIS EVENING. THE ATMOSPHERE IS SATURATING AS THE SHORT WAVE MOVES SSE OUT OF ERN NEBRASKA AND INTERACTS WITH THE SFC LOW OVER WRN IA. MODELS IN GOOD AGREEMENT THAT THE SHORT WAVE WILL STRENGTHEN AS IT DIVES THRU WRN MO OVERNIGHT AND MONDAY MORNING. MOST OF THE ECHOS ACROSS IA AND NW MO ARE VERY LIGHT ATTM BUT THE INTENSITY SHOULD INCREASE AS THE SHORT WAVE GETS CLOSER. MONDAY WILL BE A CHILLY DAMP DAY WITH PRECIP ENDING FROM N-S. NOT MUCH RISE ON TEMPS EXPECTED EITHER WITH AN ERLY WIND AND PLENTY OF CLOUDS. MILLER && .SHORT TERM... ISSUED AT 233 PM CST SUN NOV 4 2012 (TONIGHT) POTENT LITTLE SHORTWAVE IS DEVELOPING OVER NORTHEAST MONTANA...AND WILL DIVE SOUTHEAST THROUGH THE GREAT PLAINS TONIGHT. THE SURFACE REFLECTION OF THIS WAVE WILL LIKEWISE DROP SOUTHEAST INTO THE PLAINS AND LINK UP WITH A BROAD/RELATIVELY WEAK AREA OF LOW PRESSURE CURRENTLY SITTING OVER KANSAS. THE COMBINED SURFACE TROF WILL STRENGTHEN SLIGHTLY AS IT MOVES INTO NORTHWEST MISSOURI LATE TONIGHT. MODELS ARE IN GOOD AGREEMENT IN SPREADING A SWATH OF RAIN OUT SOUTHEAST AHEAD OF THE SHORTWAVE. THE ONSET OF PRECIP LOOKS FASTER THAN PREVIOUSLY THOUGHT...THE HRRR IS ESPECIALLY FAST BRINGING PRECIP INTO CENTRAL MO AS EARLY AS 03Z...AND SPREADING TO NEAR THE MISSISSIPPI RIVER BY 06Z. AM STICKING CLOSER TO THE OPERATIONAL NAM AND GFS SOLUTIONS WHICH ARE 3-6HRS SLOWER...BUT WILL BRIEF THE EVENING SHIFT TO WATCH FOR A FASTER ONSET OF RAIN. CARNEY && .LONG TERM... ISSUED AT 233 PM CST SUN NOV 4 2012 (MONDAY THROUGH SUNDAY) NORTHWEST FLOW ALIVE AND WELL ACROSS THE CENTER OF THE NATION AS A DEEP LONGWAVE TROF CONTINUES TO BE CARVED OUT ACROSS THE EASTERN CONUS. SHORTWAVE OF INTEREST IN THE SHORT TERM WILL CONTINUE TO DIVE SOUTHEAST INTO THE BASE OF THIS LONGWAVE TROF AND BE RESPONSIBLE FOR THE DEVELOPMENT OF A POWERFUL STORM SYSTEM THAT WILL MOVE UP THE EAST COAST DURING THE MIDDLE PORTION OF THIS WEEK. THIS WILL CERTAINLY BE THE NATIONS WEATHER STORY...AS THE NOR`EASTER BRINGS STRONG WIND...RAIN...AND EVEN SOME WINTER WEATHER TO AREAS STILL REELING FROM SANDY. MONDAY AND MONDAY NIGHT... MODEL GUIDANCE IN VERY GOOD AGREEMENT REGARDING THE TRACK OF THE SHORTWAVE ACROSS MISSOURI. AREA OF LIGHT RAIN WILL WORK ITS WAY SOUTH ACROSS THE REGION WITH THICK CLOUD COVER AND CHILLY TEMPERATURES. HAVE WENT A DEGREE OR TWO BELOW THE LOWEST MODEL GUIDANCE. RAIN SHOULD PUSH SOUTH OF THE AREA BY MONDAY NIGHT...BUT CLOUDS WILL HANG TOUGH IN THE WAKE OF THIS SYSTEM. HAVE KEPT TEMPERATURES WARMER THAN GUIDANCE WOULD SUGGEST...WITH A LIMITED DIURNAL TEMPERATURE SWING. TUESDAY AND WEDNESDAY... A FINAL SHORTWAVE...THE CABOOSE...WILL TRACK ACROSS THE WESTERN GREAT LAKES...PUSHING A FINAL COLD FRONT ACROSS THE AREA. LIMITED MOISTURE AND AN EASTERN TRACK TO THE DISTURBANCE KEEPS POPS AT SLIGHT CHANCE AND CONFINED TO ILLINOIS COUNTIES. SURFACE RIDGE OF HIGH PRESSURE WILL THEN BUILD ACROSS THE CWA ON WEDNESDAY WITH DRY WEATHER AND SEASONAL TEMPERATURES. THURSDAY THROUGH SUNDAY... THE UPPER AIR PATTERN WILL FINALLY TRANSITION BY WEEKS END AS A MASSIVE STORM SYSTEM CARVES A LONGWAVE TROF ACROSS THE WESTERN CONUS WHICH HELPS AMPLIFY A RIDGE DOWNSTREAM ACROSS THE EASTERN CONUS. THE END RESULT WILL BE SOUTHWEST FLOW ACROSS THE MIDWEST AND ABOVE NORMAL TEMPERATURES. THIS LARGE UPPER TROF WILL BE PROGRESSIVE WITH RAIN CHANCES INCREASING SUNDAY AND SUNDAY NIGHT. CVKING && .AVIATION... ISSUED AT 1054 PM CST SUN NOV 4 2012 AN UPPER LEVEL TROUGH AND ASSOCIATED WEAK SFC LOW WILL DROP S-SEWD THROUGH WRN MO LATE TGT AND MON MRNG. MID LEVEL CLOUDS HAVE SPREAD SEWD INTO OUR AREA THIS EVNG WITH LOW LEVEL CLOUDS AND LIGHT RAIN BEGINNING TO MOVE INTO UIN. THE CLOUD COVER WILL LOWER AND THICKEN LATE TGT WITH CIGS DROPPING INTO THE MVFR CATAGORY LATE TGT IN UIN AND COU AND IN THE ST LOUIS METRO AREA EARLY MON MRNG. THE CIGS MAY BRIEFLY DROP INTO THE IFR CATAGORY ON MON. RAIN WILL ALSO SPREAD SEWD INTO UIN AND COU LATE TGT AND INTO THE ST LOUIS METRO AREA EARLY MON MRNG WITH VSBYS FALLING TO 4-5SM. A E-SELY SFC WIND WILL BACK AROUND TO AN E-NELY DIRECTION MON AFTN AND EVNG AS THE WEAK SFC LOW SHIFTS SW OF THE AREA. THE RAIN WILL EVENTUALLY PROGRESS S-SE OF THE TAF SITES BY EARLY MON EVNG ALTHOUGH MVFR CIGS WILL LIKELY CONTINUE MON EVNG. THE SFC WIND WILL BECOME LIGHT MON EVNG. SPECIFICS FOR KSTL...THE CLOUD CEILING WILL GRADUALLY LOWER THROUGH THE LATE NIGHT HOURS...DROPPING INTO THE MVFR CATAGORY BY EARLY MON MRNG AS LIGHT RAIN MOVES INTO THE AREA. PREFER THE LOWER CIG HEIGHTS OF THE NAM MOS GUIDANCE OVER THE MORE OPTIMISTIC CIG HEIGHTS OF THE GFS MOS. RAIN WILL DROP VSBYS TO 4-5SM ON MON. THE RAIN WILL EVENTUALLY SHIFT SE OF STL BY EARLY MON EVNG ALTHOUGH MVFR CIGS WILL CONTINUE FOR MOST OF THE NIGHT. A LIGHT ELY SFC WIND WILL VEER AROUND TO A SELY DIRECTION LATE TGT...AND INCREASE TO 8-9 KTS MON MRNG. THE SFC WIND WILL BACK AROUND TO AN ELY DIRECTION BY EARLY MON EVNG AS IT BECOMES LIGHT AGAIN. GKS && .LSX WATCHES/WARNINGS/ADVISORIES... MO...NONE. IL...NONE. && $$ WFO LSX
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1059 PM CST SUN NOV 4 2012 .AVIATION...06Z KGRI TAF. MVFR CONDITIONS TO CONTINUE THROUGH 10Z...WITH IFR CONDITIONS FORECAST 10Z-14Z. VFR CONDITIONS ARE THEN EXPECTED 14Z THROUGH THE END OF THE TAF PERIOD. STRATUS WILL PERSIST AT THE TERMINAL TONIGHT...WITH CEILINGS AS LOW AS 900FT AGL CURRENTLY FORECAST. SOME GUIDANCE ALSO SUGGESTS THERE MAY BE ENOUGH LOW LEVEL MOISTURE AND TURBULENT MIXING FOR LIGHT DRIZZLE FORMATION...AND WILL KEEP THE VISIBILITY AT 6SM 10-14Z AS A RESULT. THE SURFACE WIND WILL REMAIN FROM THE NORTH/NORTHWEST THROUGH THE TAF PERIOD...INTENSIFYING TO NEAR 16KTS AND GUSTING TO AROUND 22KTS 14Z ONWARD. THERE IS A LOW POSSIBILITY OF LLWS DEVELOPMENT TONIGHT AS THE WIND JUST ABOVE THE BOUNDARY LAYER INCREASE TO NEAR 35KTS AND THE SURFACE WIND REMAINS NEAR 5KTS. WILL LEAVE ANY MENTION OF LLWS OUT OF THE TAF FOR THE TIME BEING AS IT APPEARS WIND SHEAR SHOULD REMAIN UNDER CRITERIA...BUT STILL SOMETHING TO MONITOR UNTIL THE SURFACE WIND INCREASES LATER TONIGHT. && .PREV DISCUSSION... /ISSUED 1027 PM CST SUN NOV 4 2012/ UPDATE...EVENING UPPER AIR ANALYSIS INDICATES LONG WAVE RIDGING OVER THE WESTERN HALF OF THE CONUS AND TROUGHING OVER THE EAST. MID AND UPPER LEVEL JET ENERGY EXTENDS FROM SOUTHWESTERN CANADA...SOUTHEAST ACROSS THE ROCKY MOUNTAIN RANGE AND PORTIONS OF THE PLAINS...ON INTO THE SOUTHEAST. WATER VAPOR IMAGERY ALSO INDICATES A MID LEVEL SHORT WAVE OVER THE CENTRAL PLAINS. AT THE SURFACE A COLD FRONT IS NOTED EXTENDING FROM NORTHEASTERN KANSAS INTO NORTH TEXAS. A NORTHWESTERLY LOW LEVEL WIND FIELD HAS MATERIALIZED ACROSS OUR ENTIRE CWA AS A RESULT. A BAND OF STRATUS IS NOTED ON SATELLITE IMAGERY EXTENDING FROM THE MISSOURI RIVER VALLEY...NORTH/NORTHWESTWARD WELL INTO CANADA. THE SOUTHWESTERN PERIPHERY OF THIS STRATUS COVERS ROUGHLY THE NORTHEASTERN HALF OF OUR CWA...ALTHOUGH MID AND HIGH LEVEL CLOUDS ALSO PERSIST OVER OUR SOUTHWEST THUS MOSTLY CLOUDY TO OVERCAST SKIES CONTINUE ACROSS THE ENTIRE CWA. KUEX AND KOAX INDICATE PRECIPITATION OVER THE MISSOURI RIVER VALLEY. WITH THE EXCEPTION OF PERHAPS A FEW ISOLATED SPRINKLES...DRY CONDITIONS PERSIST ACROSS OUR CWA. LATEST HRRR...NAM AND RAP DATA ALL SUGGEST LITTLE TO NO CHANCE OF MEASURABLE PRECIPITATION ACROSS OUR CWA THROUGH THE REMAINDER OF TONIGHT. WITH THE MID LEVEL TROUGH AXIS OVERHEAD OUR AREA NOW...AND NOTHING IN THE WAY OF MEASURABLE PRECIPITATION UPSTREAM...SEE LITTLE REASON TO DISAGREE WITH THESE LATEST DATA. AS A RESULT...WENT AHEAD AND PULLED THE SLIGHT CHANCE POPS ACROSS OUR EAST/NORTHEAST...AND ONLY LEFT ISOLATED SPRINKLES ACROSS OUR EAST/NORTHEAST THROUGH THE NEXT FEW HOURS TO ACCOUNT FOR THE WEAK RETURNS CURRENTLY BEING INDICATED BY KUEX. ALSO WENT AHEAD AND ADJUSTED CLOUD GRIDS A TOUCH TO REFLECT CURRENT TRENDS. GUIDANCE FROM THE NAM...OPERATIONAL GFS AND RAP ALL SUGGEST THE STRATUS WILL HOLD STRONG OVER OUR EAST/NORTHEAST TONIGHT. THAT BEING SAID...THE MID AND HIGH LEVEL CLOUDS WILL BE ON THE DECREASE ACROSS OUR WEST/SOUTHWEST THROUGH THE NEXT FEW HOURS AND WITH THE STRATUS REMAINING FARTHER NORTHEAST...OUR WEST/SOUTHWEST SHOULD SEE SIGNIFICANT CLEARING DURING THE OVERNIGHT HOURS. OVERNIGHT LOWS LOOK PRETTY WELL ON TRACK FOR THE TIME BEING. THERE IS SOME CONCERN THAT THE FORECAST LOWS ACROSS OUR EAST/NORTHEAST MAY BE A BIT WARM GIVEN THE STRATUS...BUT WITH CURRENT TEMPERATURES ALREADY IN THE LOWER 40S OUT THAT WAY...FORECAST OVERNIGHT LOWS IN THE MID 30S SHOULD VERIFY FAIRLY WELL. PREV DISCUSSION... /ISSUED 244 PM CST SUN NOV 4 2012/ SHORT TERM...TONIGHT AND MONDAY. BIGGEST CONCERN FOCUSED ON LOW CLOUDS AND ANY LIGHT PRECIP THAT MAY FALL FROM THEM TONIGHT AND EARLY MONDAY. AN UPPER LEVEL DISTURBANCE...REFLECTED AT THE SURFACE AS A COLD FRONT WILL MOVE ACROSS THE AREA OVERNIGHT. CLOUDS HAVE BEEN PROGRESSIVELY LOWERING THROUGH THE DAY AS MOISTURE ALOFT GRADUALLY MOISTENS THE AIR BELOW IT. THIS TREND IS EXPECTED TO CONTINUE INTO THE NIGHT AND EVENTUALLY THE MOISTURE SHOULD MAKE IT TO THE SURFACE. THAT SAID...THE DROPLETS ARE EXPECTED TO BE VERY SMALL...SO ONLY EXPECTING SPRINKLES AT BEST. THE BEST CHANCES FOR ANY MEASURABLE RAIN WILL BE THE FAR EASTERN AREA...CLOSER TO THE BETTER DYNAMICS AND DEEPER/MORE ABUNDANT MOISTURE. AFTER THE FRONT PASSES...THE PRESSURE GRADIENT INCREASES...SO WINDS WILL ALSO. COLD AIR ADVECTION WILL BE THE RULE ON MONDAY WITH A STRONG SUBSIDENT FLOW DEVELOPING FROM WEST TO EAST AS THE DAY PROGRESSES...THIS EXPECTING GRADUAL CLEARING AND COOLER HIGH TEMPERATURES THAN THE LAST SEVERAL DAYS. AS A MATTER OF FACT...BETWEEN THE STRONG WINDS AND COLDER TEMPERATURES THE CHANGE WILL BE QUITE NOTICEABLE BY ANYONE VENTURING OUTSIDE. THE PREVIOUS FORECAST PEGGED THESE TRENDS WELL...SO AM NOT REQUIRED TO MAKE MANY CHANGES AT ALL. LONG TERM...MONDAY NIGHT THROUGH SUNDAY. BEGINNING MONDAY NIGHT...A CLIPPER SYSTEM CROSSES FM MANITOBA INTO THE UPPER MIDWEST/GREAT LAKES REGION...SENDING AN ASSOCIATED COOL FRONTAL BOUNDARY SOUTH ACROSS THE PLAINS OVERNIGHT AND TUESDAY MORNING. COOLER AIR BACKS INTO THE EASTERN PORTION OF THE STATE BEHIND BOUNDARY LENDING TOWARD A W/E THERMAL GRADIENT FOR HIGHS IN THE AFTN...BUT STILL SEASONAL OR ABOVE FOR DAYTIME TEMPS. DRY AND MILD CONDITIONS WILL SETTLE IN THRU THE REMAINDER OF THE WORKWEEK AS UPPER RIDGE OVER THE ROCKIES EXPANDS ONTO THE PLAINS...WITH FLOW TRANSITIONING SOUTHWESTERLY AS UPPER LOW/LONG WAVE TROUGH DEEPENS ALONG THE WEST COAST BY FRIDAY. MODELS ARE IN BETTER AGREEMENT THIS TIME AROUND WITH GRADUAL EASTWARD ADVANCEMENT OF TROUGH/UPPER LOW OVER THE WEEKEND WITH THE CENTER OF THE LOW LIFTING ACROSS THE DAKOTAS SATURDAY NIGHT. BASED ON TRACK OF THE SYSTEM...WE STAY IN THE WARM SECTOR THRU FRIDAY NIGHT OR POTENTIALLY SATURDAY DEPENDING ON THE MODEL...WITH COLD FRONT SWEEPING SOUTH SATURDAY/SATURDAY NIGHT. COULD SEE SOME PCPN ENTERING OUR REGION SATURDAY/SATURDAY NIGHT WITH FROPA AND UPPER DYNAMICS WITH MODELS SUGGESTING THAT AIRMASS WILL BE SUFFICIENTLY COLD TO AT LEAST WARRANT SOME CHC FOR NON LIQUID PCPN...WITH A TRANSITION FM R/S NW/SE. BY SUNDAY...CONDITIONS DRY OUT WITH MARKEDLY COLDER AIR SETTLING IN WITH TEMPS STRUGGLING IN THE 30S FOR HIGHS. && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$ AVIATION/UPDATE...BRYANT
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1027 PM CST SUN NOV 4 2012 .UPDATE...EVENING UPPER AIR ANALYSIS INDICATES LONG WAVE RIDGING OVER THE WESTERN HALF OF THE CONUS AND TROUGHING OVER THE EAST. MID AND UPPER LEVEL JET ENERGY EXTENDS FROM SOUTHWESTERN CANADA...SOUTHEAST ACROSS THE ROCKY MOUNTAIN RANGE AND PORTIONS OF THE PLAINS...ON INTO THE SOUTHEAST. WATER VAPOR IMAGERY ALSO INDICATES A MID LEVEL SHORT WAVE OVER THE CENTRAL PLAINS. AT THE SURFACE A COLD FRONT IS NOTED EXTENDING FROM NORTHEASTERN KANSAS INTO NORTH TEXAS. A NORTHWESTERLY LOW LEVEL WIND FIELD HAS MATERIALIZED ACROSS OUR ENTIRE CWA AS A RESULT. A BAND OF STRATUS IS NOTED ON SATELLITE IMAGERY EXTENDING FROM THE MISSOURI RIVER VALLEY...NORTH/NORTHWESTWARD WELL INTO CANADA. THE SOUTHWESTERN PERIPHERY OF THIS STRATUS COVERS ROUGHLY THE NORTHEASTERN HALF OF OUR CWA...ALTHOUGH MID AND HIGH LEVEL CLOUDS ALSO PERSIST OVER OUR SOUTHWEST THUS MOSTLY CLOUDY TO OVERCAST SKIES CONTINUE ACROSS THE ENTIRE CWA. KUEX AND KOAX INDICATE PRECIPITATION OVER THE MISSOURI RIVER VALLEY. WITH THE EXCEPTION OF PERHAPS A FEW ISOLATED SPRINKLES...DRY CONDITIONS PERSIST ACROSS OUR CWA. LATEST HRRR...NAM AND RAP DATA ALL SUGGEST LITTLE TO NO CHANCE OF MEASURABLE PRECIPITATION ACROSS OUR CWA THROUGH THE REMAINDER OF TONIGHT. WITH THE MID LEVEL TROUGH AXIS OVERHEAD OUR AREA NOW...AND NOTHING IN THE WAY OF MEASURABLE PRECIPITATION UPSTREAM...SEE LITTLE REASON TO DISAGREE WITH THESE LATEST DATA. AS A RESULT...WENT AHEAD AND PULLED THE SLIGHT CHANCE POPS ACROSS OUR EAST/NORTHEAST...AND ONLY LEFT ISOLATED SPRINKLES ACROSS OUR EAST/NORTHEAST THROUGH THE NEXT FEW HOURS TO ACCOUNT FOR THE WEAK RETURNS CURRENTLY BEING INDICATED BY KUEX. ALSO WENT AHEAD AND ADJUSTED CLOUD GRIDS A TOUCH TO REFLECT CURRENT TRENDS. GUIDANCE FROM THE NAM...OPERATIONAL GFS AND RAP ALL SUGGEST THE STRATUS WILL HOLD STRONG OVER OUR EAST/NORTHEAST TONIGHT. THAT BEING SAID...THE MID AND HIGH LEVEL CLOUDS WILL BE ON THE DECREASE ACROSS OUR WEST/SOUTHWEST THROUGH THE NEXT FEW HOURS AND WITH THE STRATUS REMAINING FARTHER NORTHEAST...OUR WEST/SOUTHWEST SHOULD SEE SIGNIFICANT CLEARING DURING THE OVERNIGHT HOURS. OVERNIGHT LOWS LOOK PRETTY WELL ON TRACK FOR THE TIME BEING. THERE IS SOME CONCERN THAT THE FORECAST LOWS ACROSS OUR EAST/NORTHEAST MAY BE A BIT WARM GIVEN THE STRATUS...BUT WITH CURRENT TEMPERATURES ALREADY IN THE LOWER 40S OUT THAT WAY...FORECAST OVERNIGHT LOWS IN THE MID 30S SHOULD VERIFY FAIRLY WELL. && .PREV DISCUSSION... /ISSUED 530 PM CST SUN NOV 4 2012/ AVIATION...00Z KGRI TAF. VFR CONDITIONS EXPECTED THROUGH 07Z...WITH MVFR TO IFR CONDITIONS 07-14Z...FOLLOWED BY VFR CONDITIONS 14Z THROUGH THE END OF THE TAF PERIOD. STRATUS WILL CONTINUE TO INFILTRATE THE TERMINAL TONIGHT...WITH CEILINGS AS LOW AS 900FT AGL CURRENTLY FORECAST. LIGHT RAIN REMAINS POSSIBLE AT KGRI...BUT AT THIS TIME THE CHANCES OF MEASURABLE RAINFALL BEING OBSERVED AT THE TERMINAL ARE TOO LOW FOR INCLUSION IN THE TAF. THAT BEING SAID...SOME GUIDANCE DOES SUGGEST THERE MAY BE ENOUGH LOW LEVEL MOISTURE AND TURBULENT MIXING FOR LIGHT DRIZZLE FORMATION...AND WILL KEEP THE VISIBILITY AT 6SM 10-14Z AS A RESULT. THE SURFACE WIND WILL REMAIN FROM THE NORTH/NORTHWEST THROUGH THE TAF PERIOD...INTENSIFYING TO NEAR 16KTS AND GUSTING TO AROUND 22KTS 14Z ONWARD. PREV DISCUSSION... /ISSUED 244 PM CST SUN NOV 4 2012/ SHORT TERM...TONIGHT AND MONDAY. BIGGEST CONCERN FOCUSED ON LOW CLOUDS AND ANY LIGHT PRECIP THAT MAY FALL FROM THEM TONIGHT AND EARLY MONDAY. AN UPPER LEVEL DISTURBANCE...REFLECTED AT THE SURFACE AS A COLD FRONT WILL MOVE ACROSS THE AREA OVERNIGHT. CLOUDS HAVE BEEN PROGRESSIVELY LOWERING THROUGH THE DAY AS MOISTURE ALOFT GRADUALLY MOISTENS THE AIR BELOW IT. THIS TREND IS EXPECTED TO CONTINUE INTO THE NIGHT AND EVENTUALLY THE MOISTURE SHOULD MAKE IT TO THE SURFACE. THAT SAID...THE DROPLETS ARE EXPECTED TO BE VERY SMALL...SO ONLY EXPECTING SPRINKLES AT BEST. THE BEST CHANCES FOR ANY MEASURABLE RAIN WILL BE THE FAR EASTERN AREA...CLOSER TO THE BETTER DYNAMICS AND DEEPER/MORE ABUNDANT MOISTURE. AFTER THE FRONT PASSES...THE PRESSURE GRADIENT INCREASES...SO WINDS WILL ALSO. COLD AIR ADVECTION WILL BE THE RULE ON MONDAY WITH A STRONG SUBSIDENT FLOW DEVELOPING FROM WEST TO EAST AS THE DAY PROGRESSES...THIS EXPECTING GRADUAL CLEARING AND COOLER HIGH TEMPERATURES THAN THE LAST SEVERAL DAYS. AS A MATTER OF FACT...BETWEEN THE STRONG WINDS AND COLDER TEMPERATURES .THE CHANGE WILL BE QUITE NOTICEABLE BY ANYONE VENTURING OUTSIDE. THE PREVIOUS FORECAST PEGGED THESE TRENDS WELL...SO AM NOT REQUIRED TO MAKE MANY CHANGES AT ALL. LONG TERM...MONDAY NIGHT THROUGH SUNDAY. BEGINNING MONDAY NIGHT...A CLIPPER SYSTEM CROSSES FM MANITOBA INTO THE UPPER MIDWEST/GREAT LAKES REGION...SENDING AN ASSOCIATED COOL FRONTAL BOUNDARY SOUTH ACROSS THE PLAINS OVERNIGHT AND TUESDAY MORNING. COOLER AIR BACKS INTO THE EASTERN PORTION OF THE STATE BEHIND BOUNDARY LENDING TOWARD A W/E THERMAL GRADIENT FOR HIGHS IN THE AFTN...BUT STILL SEASONAL OR ABOVE FOR DAYTIME TEMPS. DRY AND MILD CONDITIONS WILL SETTLE IN THRU THE REMAINDER OF THE WORKWEEK AS UPPER RIDGE OVER THE ROCKIES EXPANDS ONTO THE PLAINS...WITH FLOW TRANSITIONING SOUTHWESTERLY AS UPPER LOW/LONG WAVE TROUGH DEEPENS ALONG THE WEST COAST BY FRIDAY. MODELS ARE IN BETTER AGREEMENT THIS TIME AROUND WITH GRADUAL EASTWARD ADVANCEMENT OF TROUGH/UPPER LOW OVER THE WEEKEND WITH THE CENTER OF THE LOW LIFTING ACROSS THE DAKOTAS SATURDAY NIGHT. BASED ON TRACK OF THE SYSTEM...WE STAY IN THE WARM SECTOR THRU FRIDAY NIGHT OR POTENTIALLY SATURDAY DEPENDING ON THE MODEL...WITH COLD FRONT SWEEPING SOUTH SATURDAY/SATURDAY NIGHT. COULD SEE SOME PCPN ENTERING OUR REGION SATURDAY/SATURDAY NIGHT WITH FROPA AND UPPER DYNAMICS WITH MODELS SUGGESTING THAT AIRMASS WILL BE SUFFICIENTLY COLD TO AT LEAST WARRANT SOME CHC FOR NON LIQUID PCPN...WITH A TRANSITION FM R/S NW/SE. BY SUNDAY...CONDITIONS DRY OUT WITH MARKEDLY COLDER AIR SETTLING IN WITH TEMPS STRUGGLING IN THE 30S FOR HIGHS. && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$ UPDATE/AVIATION...BRYANT
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
327 AM EST MON NOV 5 2012 .SYNOPSIS... CLOUDS...FLURRIES...AND SPRINKLES...WILL PERSIST THROUGH MUCH OF THE NIGHT FOR PORTIONS OF CENTRAL NEW YORK...AS MOISTURE CONTINUES TO STREAM OFF LAKE ONTARIO. HIGH PRESSURE WILL BUILD DOWN ACROSS THE REGION MONDAY AND TUESDAY...TO BRING DRY BUT CHILLY WEATHER. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... JUST SOME VERY LGT RETURNS ON THE RADAR THIS EVE. WILL KEEP SPRINKLES AND FLURRIES IN OVRNGT. NAM DOES SHOW A CPL MORE WEAK WVS SLIDING THRU LATE TNGT AND EARLY MON...BUT THE HRRR KEEPS ANY LGT PCPN NEAR THE LAKE SHORE OVER WRN NY. WITH THE MORE NLY FLOW...XPCT CHANCE FOR ANY LGT LE TO BE MORE PSBL OVER THE WRN ZONES AS THE NGT WEARS ON. PRVS DISC BLO. 3 PM UPDATE... CLOUDS CONTINUE TO HANG TOUGH THROUGH THE CWA LATE THIS AFTN. HOWEVER...THERE ARE SOME EARLY SIGNS OF IMPROVEMENT BEGINNING TO SHOW UP...WHICH SHOULD TAKE PLACE IN OUR ERN ZNS TNT. THE CHARACTER OF THE CLOUD COVER IS TAKING ON A MORE OPEN CELLULAR APPEARANCE EAST OF THE I-81 CORRIDOR ATTM...AND FAIRLY SIG HOLES HAVE OPENED UP IN THE EARLIER EXPANSIVE SC SHIELD UP OVER SRN QUE. SINCE OUR LOW-LVL FLOW IS EXPECTED TO TURN MORE INTO THE N AND EVEN NNE OVERNIGHT...WE THINK THIS TYPE OF ENVIR WILL SETTLE ACRS OUR ERN ZNS...WITH AT LEAST PTL CLEARING ANTICIPATED AFTER 00-03Z. MEANWHILE...FARTHER W THROUGH THE FINGER LKS RGN...WHERE A LOW-LVL MOIST FEED WILL STILL BE MAINTAINED S OF LK ONT...CLDS SHOULD BE MORE STUBBORN...WITH A FEW FLRYS EVEN ANTICIPATED...AS BLYR CAA IS RENEWED FOR A BRIEF PD OVERNIGHT. OUR NE PA ZNS SHOULD SEE SOME CLEARING DURG THE NGT...EXCPT FOR PERHAPS BRADFORD/WRN SUSQ CNTYS...WHERE THE ABV MENTIONED CLOUDS FROM LK ONT COULD MOVE IN FOR A TIME. && .SHORT TERM /6 AM THIS MORNING THROUGH WEDNESDAY NIGHT/... 305 PM UPDATE... QUIET WX FORESEEN THIS PD...WITH SFC RIDGING OUR DOMINANT FEATURE. AM CLDS/SCTD FLRYS MON IN OUR WRN ZNS...SHOULD HAVE A TENDENCY TO BREAK UP BY 18Z...AS THE DEPTH OF DRIER AIR FINALLY OVERWHELMS THE MOIST BLYR ENVIR. THEREAFTER...WE EXPECT MAINLY CLR SKIES MON NGT...AND SUNNY SKIES ON TUE. MID TO HIGH-LVL CLDS MAY WELL BEGIN TO INCREASE LTR TUE NGT...FAR IN ADVANCE OF THE WELL ADVERTISED EAST COAST STORM SLATED TO ARRIVE IN THE LONG-TERM PD (MORE ON THIS BELOW). && .LONG TERM /THURSDAY THROUGH SUNDAY/... 330 AM UPDATE... GFS AND ECMWF IN EXCELLENT AGREEMENT THAT THE FIRST MAJOR WINTER STORM OF THE SEASON WILL BE IMPACTING OUR REGION AT THE START OF THE EXTENDED PERIOD. FOR ALL INTENSIVE PURPOSES...THE TWO MODELS ARE ALMOST IDENTICAL IN TERMS OF FCST TRACK AND INTENSITY...HOWEVER SOME DISPARITY STILL REMAINS WITH EXPECTED THERMAL PROFILES ALOFT WHICH WILL HAVE IMPACTS ON BOTH P-TYPE AND ACCUMULATIONS. 00Z GFS HAS COME IN A BIT WARMER THAN PREVIOUS RUNS WITH THE CURRENT VERSION SUGGESTING H85 TEMPS WILL DROP TO ABOUT +2C OVERNIGHT WED. MEANWHILE THE ECMWF REMAINS THE COOLER SOLUTION WITH SUBZERO H85 TEMP VALUES FORECAST CWA WIDE. CONSIDERING HOW BOTH MODELS HAVE BEEN CONSISTENT IN SUGGESTING AN ELONGATED QPF AXIS EXTENDING ACROSS CENTRAL AND EASTERN PORTIONS OF THE FORECAST AREA...WE/RE INCLINED TO BELIEVE THAT ENOUGH DYNAMICAL COOLING WILL OCCUR TO FAVOR THE COOLER ECMWF SOLUTION. THAT SAID...HAVE MAINTAINED A SNOW MENTION THROUGH 18Z THU BEFORE TRANSITIONING TO RA/SN MIX BY AFTERNOON. WINTER STORM FEATURE SHOULD QUICKLY BEGIN EXITING STAGE RIGHT BY THU NGT WITH LITTLE INDICATION THAT ANY SUBSTANTIAL LAKE EFFECT WILL OCCUR IN ITS WAKE. MODELS BEGINNING TO HIT HARD THAT A RATHER SIGNIFICANT WARM UP CAN BE EXPECTED BY THE WEEKEND AS STRONG UPPER RIDGING BUILDS ACROSS THE CENTRAL/EASTERN GREAT LAKES. BOTH ECMWF AND GFS ADVERTISE H50 HEIGHTS INCREASING TO NEAR 582 DM BY EARLY SUN. IF THIS PANS OUT AS ADVERTISED...LOW 60S WILL BE POSSIBLE SUN AFTERNOON. PREVIOUS LONG TERM DISCUSSION... MAIN FEATURE TO WATCH DURING THE PERIOD WILL BE A STORM DEVELOPING OFF THE MID-ATLANTIC COAST LATE WEDNESDAY INTO EARLY FRIDAY. LATEST MODEL RUNS HAVE SHOWN THE GFS TRENDING SLIGHTLY FARTHER EAST WITH THE STORM WHILE THE ECMWF IS CLOSER TO THE COAST. THE CANADIAN MODEL APPEARS TO BE A BIT OF A COMPROMISE... MAYBE SLIGHTLY LEARNING TOWARD THE ECMWF. RUN TO RUN CONSISTENCY WITH THE MODELS HAS BEEN PRETTY GOOD WITH THIS FEATURE OVER THE PAST COUPLE OF DAYS... HOWEVER MINOR POSITIONING DIFFERENCES WILL MAKE A BIG DIFFERENCE IN THE WEATHER FOR OUR AREA. THE GFS WOULD BASICALLY INDICATE A NON- EVENT FOR OUR AREA... THE CANADIAN WOULD INDICATE A MAJOR SNOW STORM FOR THE EASTERN HALF OF THE AREA... AND THE ECMWF ACTUALLY INDICATES THE MOST SNOW FOR OUR CENTRAL COUNTIES... ALONG THE I-81 CORRIDOR. OBVIOUSLY TOO SOON TO PIN DOWN DETAILS AT THIS POINT... BUT IT DOES APPEAR THAT A SIGNIFICANT EVENT IS POSSIBLE. HAVE KEPT OUR CURRENT RAIN/SNOW FORECAST FOR THE AREA WITH HIGHEST POPS WEDNESDAY NIGHT INTO THURSDAY. THE ONLY ADJUSTMENT WITH THIS PACKAGE WAS TO SLIGHTLY SLOW DOWN THE ONSET OF PRECIPITATION DURING THE AFTERNOON WEDNESDAY. THE STORM WINDS DOWN BY FRIDAY... AND AT THIS POINT NEXT WEEKEND LOOKS DRY WITH A WARMING TREND. && .AVIATION /08Z MONDAY THROUGH FRIDAY/... A MIX OF MVFR AND VFR CONDITIONS EXPECTED AT AREA TERMINALS EARLY THIS MORNING AS NORTHERLY LOW-LEVEL FLOW RESULTS IN LAKE EFFECT CLOUDS ACROSS MUCH OF CENTRAL NY. FORECAST MODELS SUGGEST SOME DRY AIR MAY TEMPORARILY MOVE INTO THE REGION TOWARDS MORNING WHICH SHOULD PREVENT ANY IFR CONDITIONS FROM FORMING AT BGM AND ITH. AFTER 13Z...EXPECT CONDITIONS TO GRADUALLY INCREASE TO VFR AT ALL SITES WITH WINDS REMAINING FROM THE NORTH AND NORTHWEST BETWEEN 5-10 KTS. HIGH PRESSURE WILL CONTINUE TO BUILD INTO THE REGION THROUGH THE OVERNIGHT HRS RESULTING IN NEARLY CALM WINDS WITH A SCT-BKN CLOUD DECK BETWEEN 4-5 KFT AFTER 00Z. OUTLOOK... TUE...VFR. WED TO THU NGT...MVFR IN RAIN AND SNOW. FRI...MVFR IN CENTRAL NY WITH LAKE EFFECT SHOWERS. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...NONE. NY...NONE. && $$ SYNOPSIS...MLJ NEAR TERM...DGM/MLJ SHORT TERM...MLJ LONG TERM...CMG/MSE AVIATION...CMG
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1247 AM EST MON NOV 5 2012 .SYNOPSIS... CLOUDS...FLURRIES...AND SPRINKLES...WILL PERSIST THROUGH MUCH OF THE NIGHT FOR PORTIONS OF CENTRAL NEW YORK...AS MOISTURE CONTINUES TO STREAM OFF LAKE ONTARIO. HIGH PRESSURE WILL BUILD DOWN ACROSS THE REGION MONDAY AND TUESDAY...TO BRING DRY BUT CHILLY WEATHER. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... JUST SOME VERY LGT RETURNS ON THE RADAR THIS EVE. WILL KEEP SPRINKLES AND FLURRIES IN OVRNGT. NAM DOES SHOW A CPL MORE WEAK WVS SLIDING THRU LATE TNGT AND EARLY MON...BUT THE HRRR KEEPS ANY LGT PCPN NEAR THE LAKE SHORE OVER WRN NY. WITH THE MORE NLY FLOW...XPCT CHANCE FOR ANY LGT LE TO BE MORE PSBL OVER THE WRN ZONES AS THE NGT WEARS ON. PRVS DISC BLO. 3 PM UPDATE... CLOUDS CONTINUE TO HANG TOUGH THROUGH THE CWA LATE THIS AFTN. HOWEVER...THERE ARE SOME EARLY SIGNS OF IMPROVEMENT BEGINNING TO SHOW UP...WHICH SHOULD TAKE PLACE IN OUR ERN ZNS TNT. THE CHARACTER OF THE CLOUD COVER IS TAKING ON A MORE OPEN CELLULAR APPEARANCE EAST OF THE I-81 CORRIDOR ATTM...AND FAIRLY SIG HOLES HAVE OPENED UP IN THE EARLIER EXPANSIVE SC SHIELD UP OVER SRN QUE. SINCE OUR LOW-LVL FLOW IS EXPECTED TO TURN MORE INTO THE N AND EVEN NNE OVERNIGHT...WE THINK THIS TYPE OF ENVIR WILL SETTLE ACRS OUR ERN ZNS...WITH AT LEAST PTL CLEARING ANTICIPATED AFTER 00-03Z. MEANWHILE...FARTHER W THROUGH THE FINGER LKS RGN...WHERE A LOW-LVL MOIST FEED WILL STILL BE MAINTAINED S OF LK ONT...CLDS SHOULD BE MORE STUBBORN...WITH A FEW FLRYS EVEN ANTICIPATED...AS BLYR CAA IS RENEWED FOR A BRIEF PD OVERNIGHT. OUR NE PA ZNS SHOULD SEE SOME CLEARING DURG THE NGT...EXCPT FOR PERHAPS BRADFORD/WRN SUSQ CNTYS...WHERE THE ABV MENTIONED CLOUDS FROM LK ONT COULD MOVE IN FOR A TIME. && .SHORT TERM /6 AM THIS MORNING THROUGH TUESDAY NIGHT/... 305 PM UPDATE... QUIET WX FORESEEN THIS PD...WITH SFC RIDGING OUR DOMINANT FEATURE. AM CLDS/SCTD FLRYS MON IN OUR WRN ZNS...SHOULD HAVE A TENDENCY TO BREAK UP BY 18Z...AS THE DEPTH OF DRIER AIR FINALLY OVERWHELMS THE MOIST BLYR ENVIR. THEREAFTER...WE EXPECT MAINLY CLR SKIES MON NGT...AND SUNNY SKIES ON TUE. MID TO HIGH-LVL CLDS MAY WELL BEGIN TO INCREASE LTR TUE NGT...FAR IN ADVANCE OF THE WELL ADVERTISED EAST COAST STORM SLATED TO ARRIVE IN THE LONG-TERM PD (MORE ON THIS BELOW). && .LONG TERM /WEDNESDAY THROUGH SUNDAY/... MAIN FEATURE TO WATCH DURING THE PERIOD WILL BE A STORM DEVELOPING OFF THE MID-ATLANTIC COAST LATE WEDNESDAY INTO EARLY FRIDAY. LATEST MODEL RUNS HAVE SHOWN THE GFS TRENDING SLIGHTLY FARTHER EAST WITH THE STORM WHILE THE ECMWF IS CLOSER TO THE COAST. THE CANADIAN MODEL APPEARS TO BE A BIT OF A COMPROMISE... MAYBE SLIGHTLY LEARNING TOWARD THE ECMWF. RUN TO RUN CONSISTENCY WITH THE MODELS HAS BEEN PRETTY GOOD WITH THIS FEATURE OVER THE PAST COUPLE OF DAYS... HOWEVER MINOR POSITIONING DIFFERENCES WILL MAKE A BIG DIFFERENCE IN THE WEATHER FOR OUR AREA. THE GFS WOULD BASICALLY INDICATE A NON- EVENT FOR OUR AREA... THE CANADIAN WOULD INDICATE A MAJOR SNOW STORM FOR THE EASTERN HALF OF THE AREA... AND THE ECMWF ACTUALLY INDICATES THE MOST SNOW FOR OUR CENTRAL COUNTIES... ALONG THE I-81 CORRIDOR. OBVIOUSLY TOO SOON TO PIN DOWN DETAILS AT THIS POINT... BUT IT DOES APPEAR THAT A SIGNIFICANT EVENT IS POSSIBLE. HAVE KEPT OUR CURRENT RAIN/SNOW FORECAST FOR THE AREA WITH HIGHEST POPS WEDNESDAY NIGHT INTO THURSDAY. THE ONLY ADJUSTMENT WITH THIS PACKAGE WAS TO SLIGHTLY SLOW DOWN THE ONSET OF PRECIPITATION DURING THE AFTERNOON WEDNESDAY. THE STORM WINDS DOWN BY FRIDAY... AND AT THIS POINT NEXT WEEKEND LOOKS DRY WITH A WARMING TREND. && .AVIATION /06Z MONDAY THROUGH FRIDAY/... A MIX OF MVFR AND VFR CONDITIONS EXPECTED AT AREA TERMINALS EARLY THIS MORNING AS NORTHERLY LOW-LEVEL FLOW RESULTS IN LAKE EFFECT CLOUDS ACROSS MUCH OF CENTRAL NY. FORECAST MODELS SUGGEST SOME DRY AIR MAY TEMPORARILY MOVE INTO THE REGION TOWARDS MORNING WHICH SHOULD PREVENT ANY IFR CONDITIONS FROM FORMING AT BGM AND ITH. AFTER 13Z...EXPECT CONDITIONS TO GRADUALLY INCREASE TO VFR AT ALL SITES WITH WINDS REMAINING FROM THE NORTH AND NORTHWEST BETWEEN 5-10 KTS. HIGH PRESSURE WILL CONTINUE TO BUILD INTO THE REGION THROUGH THE OVERNIGHT HRS RESULTING IN NEARLY CALM WINDS WITH A SCT-BKN CLOUD DECK BETWEEN 4-5 KFT AFTER 00Z. OUTLOOK... TUE...VFR. WED TO THU NGT...MVFR IN RAIN AND SNOW. FRI...MVFR IN CENTRAL NY WITH LAKE EFFECT SHOWERS. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...NONE. NY...NONE. && $$ SYNOPSIS...MLJ NEAR TERM...DGM/MLJ SHORT TERM...MLJ LONG TERM...MSE AVIATION...CMG
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
343 AM EST MON NOV 5 2012 .SYNOPSIS... A COLD FRONT WILL MOVE OFF SHORE BY THIS MORNING AS COOL AND DRY HIGH PRESSURE BUILDS IN FROM THE NORTH. A COASTAL STORM IS EXPECTED TO IMPACT THE EASTERN CAROLINAS TUESDAY THROUGH EARLY WEDNESDAY...BRINGING BRISK NORTHERLY WINDS AND CHILLY RAIN. A DRYING TREND IS EXPECTED BEGINNING ON WEDNESDAY...ACCOMPANIED BY A WARMING TREND INTO LATE NEXT WEEK AS HIGH PRESSURE BUILDS IN. && .NEAR TERM /THROUGH TONIGHT/... AS OF 300 AM MONDAY...SFC HIGH PRESSURE TO TEMPORARILY WEDGE ACROSS THE ILM CWA THROUGH THE MAJORITY OF TONIGHT. THE COLD FRONT THAT PUSHED THROUGH LAST NIGHT HAS STALLED OFFSHORE FROM THE FA AND ORIENTED PARALLEL TO THE CAROLINAS COASTS. POST FRONTAL BROKEN TO OVERCAST LOW TO MID LEVEL CLOUDS...4K TO 120K FT...WILL RULE THE EARLY MORNING HRS THROUGH MID-MORNING. POST FRONTAL LOW TO MID-LEVEL DRIER AIR TO WORK ITS WAY ACROSS THE FA AND AID IN THE SCOURING OUT OF THESE CLOUDS BY MID-DAY...VIA VARIOUS MODEL TIME HEIGHT SECTIONS OF SEVERAL LOCATIONS ACROSS THE FA. HIGH LEVEL MOISTURE IN THE FORM OF CI/CS WILL BE RATHER THIN DURING TODAY...THEN GRADUALLY BECOME MORE OPAQUE TONIGHT AND DROPPING FROM 250K FT TO 200K FT. RATHER POTENT S/W TROF WITHIN THE LONGWAVE UPPER TROF AFFECTING THE EASTERN HALF OF THE U.S....WILL DIVE SE TO THE EASTERN GULF COAST STATES BY DAYBREAK TUE. MODELS SIMILAR WITH THIS AGGRESSIVE S/W TROF MOVEMENT...AS IT BECOMES NEUTRAL-LY TILTED BY DAYBREAK TUE. LOOK FOR THE TAPPING OF GULF MOISTURE WITHIN THIS AMPLIFIED FLOW ALOFT...AND WILL INDICATE INCREASING MID LEVEL CLOUDS AFTER MIDNIGHT TONIGHT...WITH A SLIGHT CHANCE OF STRATIFORM LIGHT RAIN ACROSS ROUGHLY THE SOUTHERN PORTIONS OF THE FA BY DAYBREAK TUE. MAX TEMPS TODAY TO RANGE FROM THE UPPER 50S NORTHERN PORTIONS OF THE ILM CWA...TO THE MID 60S ACROSS THE SOUTHERN PORTIONS OF THE FA. MIN TEMPS TONIGHT TO RANGE AND DROP TO THE MID 30S NORTH PORTIONS...TO NEAR 40 SOUTHERN PORTIONS. ALONG THE IMMEDIATE COAST...40 TO 45 RANGE. && .SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... AS OF 3 AM MONDAY...BIG STORY WILL CONTINUE TO BE LOW PRESSURE WHICH STARTS TO DEVELOP OVER THE NORTHEASTERN GULF OF MEXICO TUE MORNING AND ACROSS NORTHERN FL DURING TUE. FORECAST REASONING HAS NOT CHANGED...STRONG UPPER LEVEL DIVERGENCE/JETTING COMBINED WITH POSITIVE VORTICITY ADVECTION AND INSTABILITY BROUGHT ON BY NEGATIVELY TILTED TROUGH HELP LOW PRESSURE RAPIDLY DEEPEN AS IT MOVES NORTHEAST OFF THE SOUTHEAST COAST. TIMING AND LOCATION DIFFERENCES CONTINUE BETWEEN THE GFS...THE GFS ENSEMBLES...THE CANADIAN...AND THE ECMWF. THE CANADIAN HAS BEEN RATHER INCONSISTENT OVER THE LAST 24 TO 48 HOURS THUS IT IS BEING DISREGARDED. GFS REMAINS THE FASTEST...THOUGH IT HAS SLOWED SOME SINCE YESTERDAY. CONVERSELY THE ECMWF IS SLIGHTLY FASTER THAN EARLIER SOLUTIONS RESULTING IN A RATHER SMALL DIFFERENCE BETWEEN THE GFS/12Z ECMWF SOLUTIONS AT 12Z WED...BASICALLY EAST OF HATTERAS(GFS) OR SOUTHEAST OF CAPE LOOKOUT(ECMWF). INTERESTINGLY THE 00Z ECMWF HAS COME IN A LITTLE FASTER THAN THE GFS WITH 12Z WED LOW POSITION JUST NORTHEAST OF HATTERAS. OVERALL THESE DIFFERENCES ARE QUITE SMALL GIVEN THE CIRCUMSTANCES SO FEELING A LITTLE MORE CONFIDENT IN THE FORECAST. PLAN TO HOLD ONTO PRECIP ACROSS PORTIONS OF COASTAL NC INTO EARLY AFTERNOON WED BEFORE DRYING OUT THE ENTIRE AREA. CONDITIONS WILL BE ON THE BREEZY SIDE...ESPECIALLY WED AS THE STORM REALLY BEGINS TO DEEPEN AS IT PULLS AWAY FROM THE REGION. BOTH ECMWF AND LATEST GFS HINT AT WEAK SHORTWAVE DROPPING SOUTH THROUGH THE TN VALLEY ON WED...CROSSING THE CAROLINAS WED NIGHT. THIS FEATURE MAY PRODUCE SOME WEAK INSTABILITY SHOWERS ACROSS THE TN VALLEY AND WESTERN PORTIONS OF THE CAROLINAS WED. FEATURE ARRIVES AT THE COAST TO LATE TO TAP INTO ANY DIURNAL INSTABILITY AND IS NOT LIKELY TO GENERATE MUCH BESIDE A BRIEF MID LEVEL CLOUD DECK. CLOUD COVER...COLD ADVECTION...AND RAIN WILL KEEP HIGHS BELOW CLIMO ON TUE. ALTHOUGH RAIN ENDS WED COLD ADVECTION AND LINGERING CLOUD COVER WILL MAINTAIN HIGHS WELL BELOW CLIMO WED. COLD ADVECTION WILL KEEP LOWS BELOW CLIMO...THOUGH NOT AS FAR BELOW CLIMO AS HIGHS. && .LONG TERM /THURSDAY THROUGH SUNDAY/... AS OF 3 AM MONDAY...MEDIUM RANGE WILL BE DRY WITH TEMPERATURES TRENDING BACK TO CLIMO AND POSSIBLY ABOVE BY THE START OF NEXT WEEK. MID LEVEL LONGWAVE TROUGH ASSOCIATED WITH THE EARLY-MID WEEK STORM WILL LINGER OVER THE REGION THU INTO FRI...WITH AXIS JUST OFF THE COAST. THE RESULT WILL BE DEEP DRY NORTHWEST FLOW...THOUGH REMAINING A LITTLE ON THE GUSTY SIDE WITH GRADIENT BEING SLOW TO RELAX. SURFACE AND MID LEVEL RIDGING BUILD IN FROM THE SOUTHWEST FOR THE WEEKEND...KEEPING THE REGION DRY. THERE IS SOME UNCERTAINTY LATE IN THE PERIOD REGARDING THE LOCATION OF THE SURFACE AND MID LEVEL RIDGE AXIS...GFS HAD BEEN FASTER MOVING THEM OFFSHORE AND DEVELOPING RETURN FLOW. LATEST GFS IS IN BETTER AGREEMENT WITH THE ECMWF LATE IN THE PERIOD WITH NORTHEAST TO EAST FLOW CONTINUING INTO NEXT WEEK. && .AVIATION /09Z MONDAY THROUGH FRIDAY/... AS OF 06Z...THE LINE OF SHOWERS AND TSTMS HAS FINALLY MOVED OFFSHORE...AND NOW FOR THE REMAINDER OF THE OVERNIGHT... POST-FRONTAL -SHRA MAINLY VCSH TO AFFECT THE IMMEDIATE COAST UP TO A FEW HRS PRIOR TO DAYBREAK B4 MOVING OFF THE COAST FOR GOOD. HAVE STAYED CLOSER TO THE GFS AND RUC SOUNDINGS FOR BEING LESS AGGRESSIVE AND COVERAGE OF POST FRONTAL CEILINGS BELOW 1K FT. FOR THE MOST PART A 3K TO 6 K FT DECK OF CLOUDS WILL DOMINATE EARLY THIS MORNING...SCATTERING OUT LATER THIS MORNING AND AFTERNOON AS POST FRONTAL DRIER AIR AND COLD AIR ADVECTION INFILTRATES THE FA. VFR CONDITIONS TO PREVAIL FOR THE REMAINDER OF THE TAF PERIOD. POST FRONTAL NNE TO NE WINDS 8 TO 13 KNOTS WILL PREVAIL WITH GUSTS 15 TO 20 KT POSSIBLE DURING DAYLIGHT HRS OF MONDAY. WINDS WILL BACK TO AROUND 5 KNOTS AFTER SUNSET. EXTENDED OUTLOOK...CHANCE OF STRATIFORM LIGHT TO MODERATE RAINS WITH ISOLATED HEAVIER SHOWERS AND POSSIBLE TSTMS FOR THE COASTAL TERMS...FROM LATE MORNING TUESDAY THROUGH WEDNESDAY WITH OCCASIONAL PERIODS OF MVFR/IFR CONDITIONS POSSIBLE. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 300 AM MONDAY...EARLIER PASSAGE OF THE COLD FRONT...WILL STALL WELL OFFSHORE FROM THE LOCAL WATERS THROUGH TONIGHT. NORTH TO NORTHEAST WINDS WILL PREVAIL ACROSS THE AREA AS HIGH PRESSURE TEMPORARILY WEDGES ACROSS THE CAROLINAS FROM THE NE STATES THROUGH TONIGHT. THROUGH TONIGHT...A TIGHTENED SFC PG WILL RESULT WITH WIND SPEEDS 15 TO 20 KT OR 15 KT SUSTAINED WITH GUSTS UP TO 20 KT. SIGNIFICANT SEAS WILL BUILD TO 3 TO 5 FT BY LATE TODAY AND HOLD AT THESE HEIGHTS THRU TONIGHT. WIND DRIVEN WAVES WILL DOMINATE SIG. SEAS...WITH A CONTINUED UNDERLYING EASTERLY 1 FOOT OR LESS GROUND SWELL AT 12 SECOND PERIODS. SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... AS OF 3 AM MONDAY...HEADLINES WILL LIKELY BE REQUIRED FOR A LARGE PORTION OF THE PERIOD AS DEEPENING LOW PRESSURE MOVES FROM NORTHERN FL ON TUE TO NEAR HATTERAS WED MORNING AND OFF THE SOUTHERN NJ COAST AT THE END OF THE PERIOD. DURING TUE GRADIENT BECOMES MORE DEFINED BUT IT IS TUE NIGHT AND WED WHEN GRADIENT BECOMES TIGHT AS LOW STARTS TO RAPIDLY DEEPEN. AT THIS POINT IT DOES NOT APPEAR THAT GALES WILL BE MET BUT 15 TO 25 KT WINDS THROUGH THE PERIOD WILL CERTAINLY PUSH SEAS OVER 6 FT...MAINLY TUE INTO WED AS SPEEDS INCREASE BUT DIRECTION REMAINS NORTHEAST. AS WINDS BACK TO NORTHWEST WED INTO WED NIGHT OFFSHORE COMPONENT WILL BEGIN PUSHING HIGHEST SEAS BEYOND 20 NM. LONG TERM /THURSDAY THROUGH FRIDAY/... AS OF 3 AM MONDAY...WEST TO NORTHWEST FLOW WILL GRADUALLY DECREASE THROUGH THE PERIOD. GRADIENT RELAXES AS DEEPENING LOW MOVES NORTHEAST AND HIGH PRESSURE STARTS TO BUILD IN FROM THE WEST. ON THU FLOW WILL HAVE MORE OF A WESTERLY COMPONENT WITH SPEEDS 15 TO 20 KT BEFORE WINDS START TO SHIFT TO NORTHEAST AND DROP TO AROUND 15 KT THU NIGHT. 10 TO 15 KT NORTHWEST WINDS FRI DROP TO 10 KT OR LESS AND BECOME MORE NORTHERLY AS THE PERIOD ENDS. SEAS 3 TO 5 FT AT THE START OF THE PERIOD WILL SUBSIDE THROUGH THE PERIOD...KNOCKED DOWN TO 2 TO 3 FT BY THE END OE THE PERIOD BY DECREASING OFFSHORE FLOW. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...NONE. && $$ SYNOPSIS...III NEAR TERM...DCH SHORT TERM...III LONG TERM...III AVIATION...DCH/BJR
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
301 AM EST MON NOV 5 2012 .SYNOPSIS... A COLD FRONT WILL MOVE OFF SHORE BY THIS MORNING AS COOL AND DRY HIGH PRESSURE BUILDS IN FROM THE NORTH. A COASTAL STORM IS EXPECTED TO IMPACT THE EASTERN CAROLINAS TUESDAY THROUGH EARLY WEDNESDAY...BRINGING BRISK NORTHERLY WINDS AND CHILLY RAIN. A DRYING TREND IS EXPECTED BEGINNING ON WEDNESDAY...ACCOMPANIED BY A WARMING TREND INTO LATE NEXT WEEK AS HIGH PRESSURE BUILDS IN. && .NEAR TERM /THROUGH TONIGHT/... AS OF 9:45 PM SUNDAY...ONE LAST LINE OF CONVECTION MOVING ACROSS THE CAPE FEAR REGION THIS EVENING...WHICH WILL BE FOLLOWED BY ISOLATED POP-UP SHOWERS THROUGH THE OVERNIGHT PERIOD. HAVE ADJUSTED THE FORECAST TO REFLECT THESE LATEST PRECIP TRENDS. LOOKS LIKE DANGER OF SEVERE STORMS IS OVER FOR THE NIGHT. RELEVANT PORTION OF DISCUSSION FROM THIS AFTERNOON FOLLOWS: DRIER AND COOLER AIR WILL SPILL SOUTHWARD OVERNIGHT...WITH RAIN MOVING OFF THE NC/SC COAST AROUND DAYBREAK. MINIMUM TEMPERATURES IN LOW 40S NORTH ZONES TO THE UPPER 40S NEAR 50 ACROSS THE VERY SOUTH IS ANTICIPATED. A FEW SHOWERS OR LIGHT RAIN MAY LINGER ALONG THE IMMEDIATE COAST AT 12Z(7AM)...BUT THE BULK OF SHOWERS WILL RESIDE OFFSHORE AT FIRST LIGHT OF MONDAY. && .SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... AS OF 3 AM MONDAY...BIG STORY WILL CONTINUE TO BE LOW PRESSURE WHICH STARTS TO DEVELOP OVER THE NORTHEASTERN GULF OF MEXICO TUE MORNING AND ACROSS NORTHERN FL DURING TUE. FORECAST REASONING HAS NOT CHANGED...STRONG UPPER LEVEL DIVERGENCE/JETTING COMBINED WITH POSITIVE VORTICITY ADVECTION AND INSTABILITY BROUGHT ON BY NEGATIVELY TILTED TROUGH HELP LOW PRESSURE RAPIDLY DEEPEN AS IT MOVES NORTHEAST OFF THE SOUTHEAST COAST. TIMING AND LOCATION DIFFERENCES CONTINUE BETWEEN THE GFS...THE GFS ENSEMBLES...THE CANADIAN...AND THE ECMWF. THE CANADIAN HAS BEEN RATHER INCONSISTENT OVER THE LAST 24 TO 48 HOURS THUS IT IS BEING DISREGARDED. GFS REMAINS THE FASTEST...THOUGH IT HAS SLOWED SOME SINCE YESTERDAY. CONVERSELY THE ECMWF IS SLIGHTLY FASTER THAN EARLIER SOLUTIONS RESULTING IN A RATHER SMALL DIFFERENCE BETWEEN THE GFS/12Z ECMWF SOLUTIONS AT 12Z WED...BASICALLY EAST OF HATTERAS(GFS) OR SOUTHEAST OF CAPE LOOKOUT(ECMWF). INTERESTINGLY THE 00Z ECMWF HAS COME IN A LITTLE FASTER THAN THE GFS WITH 12Z WED LOW POSITION JUST NORTHEAST OF HATTERAS. OVERALL THESE DIFFERENCES ARE QUITE SMALL GIVEN THE CIRCUMSTANCES SO FEELING A LITTLE MORE CONFIDENT IN THE FORECAST. PLAN TO HOLD ONTO PRECIP ACROSS PORTIONS OF COASTAL NC INTO EARLY AFTERNOON WED BEFORE DRYING OUT THE ENTIRE AREA. CONDITIONS WILL BE ON THE BREEZY SIDE...ESPECIALLY WED AS THE STORM REALLY BEGINS TO DEEPEN AS IT PULLS AWAY FROM THE REGION. BOTH ECMWF AND LATEST GFS HINT AT WEAK SHORTWAVE DROPPING SOUTH THROUGH THE TN VALLEY ON WED...CROSSING THE CAROLINAS WED NIGHT. THIS FEATURE MAY PRODUCE SOME WEAK INSTABILITY SHOWERS ACROSS THE TN VALLEY AND WESTERN PORTIONS OF THE CAROLINAS WED. FEATURE ARRIVES AT THE COAST TO LATE TO TAP INTO ANY DIURNAL INSTABILITY AND IS NOT LIKELY TO GENERATE MUCH BESIDE A BRIEF MID LEVEL CLOUD DECK. CLOUD COVER...COLD ADVECTION...AND RAIN WILL KEEP HIGHS BELOW CLIMO ON TUE. ALTHOUGH RAIN ENDS WED COLD ADVECTION AND LINGERING CLOUD COVER WILL MAINTAIN HIGHS WELL BELOW CLIMO WED. COLD ADVECTION WILL KEEP LOWS BELOW CLIMO...THOUGH NOT AS FAR BELOW CLIMO AS HIGHS. && .LONG TERM /THURSDAY THROUGH SUNDAY/... AS OF 3 AM MONDAY...MEDIUM RANGE WILL BE DRY WITH TEMPERATURES TRENDING BACK TO CLIMO AND POSSIBLY ABOVE BY THE START OF NEXT WEEK. MID LEVEL LONGWAVE TROUGH ASSOCIATED WITH THE EARLY-MID WEEK STORM WILL LINGER OVER THE REGION THU INTO FRI...WITH AXIS JUST OFF THE COAST. THE RESULT WILL BE DEEP DRY NORTHWEST FLOW...THOUGH REMAINING A LITTLE ON THE GUSTY SIDE WITH GRADIENT BEING SLOW TO RELAX. SURFACE AND MID LEVEL RIDGING BUILD IN FROM THE SOUTHWEST FOR THE WEEKEND...KEEPING THE REGION DRY. THERE IS SOME UNCERTAINTY LATE IN THE PERIOD REGARDING THE LOCATION OF THE SURFACE AND MID LEVEL RIDGE AXIS...GFS HAD BEEN FASTER MOVING THEM OFFSHORE AND DEVELOPING RETURN FLOW. LATEST GFS IS IN BETTER AGREEMENT WITH THE ECMWF LATE IN THE PERIOD WITH NORTHEAST TO EAST FLOW CONTINUING INTO NEXT WEEK. && .AVIATION /08Z MONDAY THROUGH FRIDAY/... AS OF 06Z...THE LINE OF SHOWERS AND TSTORMS HAS FINALLY MOVED OFFSHORE...AND NOW FOR THE REMAINDER OF THE OVERNIGHT... POST-FRONTAL -SHRA MAINLY VCSH TO AFFECT THE IMMEDIATE COAST UP TO A FEW HRS PRIOR TO DAYBREAK B4 MOVING OFF THE COAST FOR GOOD. HAVE STAYED CLOSER TO THE GFS AND RUC SOUNDINGS FOR BEING LESS AGGRESSIVE AND COVERAGE OF POST FRONTAL CEILINGS BELOW 1K FT. FOR THE MOST PART A 3K TO 6 K FT DECK OF CLOUDS WILL DOMINATE EARLY THIS MORNING...SCATTERING OUT LATER THIS MORNING AND AFTERNOON AS POST FRONTAL DRIER AIR AND COLD AIR ADVECTION INFILTRATES THE FA. VFR CONDITIONS TO PREVAIL FOR THE REMAINDER OF THE TAF PERIOD. POST FRONTAL NNE TO NE WINDS 8 TO 13 KNOTS WILL PREVAUIL WITH GUSTS 15 TO 20 KT POSSIBLE DURING DAYLIGHT HRS OF MONDAY. WINDS WILL BACK TO AROUND 5 KNOTS AFTER SUNSET. EXTENDED OUTLOOK...CHANCE OF STRATIFORM LIGHT TO MODERATE RAINS WITH ISOLATED HEAVIER SHOWERS AND POSSIBLE TSTORMS FOR THE COASTAL TERMS...FROM LATE MORNING TUESDAY THROUGH WEDNESDAY WITH OCCASIONAL PERIODS OF MVFR/IFR CONDITIONS POSSIBLE. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 10:30 PM SUNDAY...STRONG THUNDERSTORM ACTIVITY NOW CONFINED TO THE WATERS BEYOND 20 NM FROM SHORE. HAVE ADJUSTED FORECAST ACCORDINGLY. NO OTHER CHANGES TO THE FORECAST...PREVIOUS DISCUSSION FOLLOWS: CHANGEABLE WINDS EXPECTED OVER THE WATERS INTO TONIGHT AS A SURFACE LOW COMPLEX MOVES EAST AND OFFSHORE THIS EVENING...THEN PULLS A COLD FRONT SOUTHWARD OVER THE 0-20NM WATERS OVERNIGHT. WINDS AHEAD AND BEHIND THE FRONT WILL HAVE THE POTENTIAL TO INDUCE 20 KT GUSTS. THIS WILL BE PARTICULARLY TRUE LATE TONIGHT AS A NORTH SURGE OF WIND PUSHES SOUTHWARD OVER RELATIVELY MILD SEA SURFACE TEMPERATURES. SEAS WILL RUN MAINLY IN A 2-4 FOOT RANGE AND HIGHEST OFFSHORE AND AROUND THE OCEAN SHOALS. NO CAUTIONARY STATEMENTS OR ADVISORIES APPEAR TO BE NEEDED FOR NOW...BUT THE SEA WILL REMAIN BUMPY THROUGH DAYBREAK MONDAY DUE TO VARIABLE WIND DIRECTIONS TONIGHT...FOLLOWED BY MODERATE WIND- SPEEDS OVERNIGHT AND EARLY MONDAY. SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... AS OF 3 AM MONDAY...HEADLINES WILL LIKELY BE REQUIRED FOR A LARGE PORTION OF THE PERIOD AS DEEPENING LOW PRESSURE MOVES FROM NORTHERN FL ON TUE TO NEAR HATTERAS WED MORNING AND OFF THE SOUTHERN NJ COAST AT THE END OF THE PERIOD. DURING TUE GRADIENT BECOMES MORE DEFINED BUT IT IS TUE NIGHT AND WED WHEN GRADIENT BECOMES TIGHT AS LOW STARTS TO RAPIDLY DEEPEN. AT THIS POINT IT DOES NOT APPEAR THAT GALES WILL BE MET BUT 15 TO 25 KT WINDS THROUGH THE PERIOD WILL CERTAINLY PUSH SEAS OVER 6 FT...MAINLY TUE INTO WED AS SPEEDS INCREASE BUT DIRECTION REMAINS NORTHEAST. AS WINDS BACK TO NORTHWEST WED INTO WED NIGHT OFFSHORE COMPONENT WILL BEGIN PUSHING HIGHEST SEAS BEYOND 20 NM. LONG TERM /THURSDAY THROUGH FRIDAY/... AS OF 3 AM MONDAY...WEST TO NORTHWEST FLOW WILL GRADUALLY DECREASE THROUGH THE PERIOD. GRADIENT RELAXES AS DEEPENING LOW MOVES NORTHEAST AND HIGH PRESSURE STARTS TO BUILD IN FROM THE WEST. ON THU FLOW WILL HAVE MORE OF A WESTERLY COMPONENT WITH SPEEDS 15 TO 20 KT BEFORE WINDS START TO SHIFT TO NORTHEAST AND DROP TO AROUND 15 KT THU NIGHT. 10 TO 15 KT NORTHWEST WINDS FRI DROP TO 10 KT OR LESS AND BECOME MORE NORTHERLY AS THE PERIOD ENDS. SEAS 3 TO 5 FT AT THE START OF THE PERIOD WILL SUBSIDE THROUGH THE PERIOD...KNOCKED DOWN TO 2 TO 3 FT BY THE END OE THE PERIOD BY DECREASING OFFSHORE FLOW. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...NONE. && $$ NEAR TERM...REK SHORT TERM...III LONG TERM...III AVIATION...DCH/BJR
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
111 AM EST MON NOV 5 2012 .SYNOPSIS... A COLD FRONT WILL CONTINUE TO MOVE SOUTH ACROSS THE AREA. THE FRONT WILL MOVE OFF SHORE BY MONDAY MORNING AS COOL AND DRY HIGH PRESSURE BUILDS IN FROM THE NORTH. A COASTAL STORM IS EXPECTED TO IMPACT THE EASTERN CAROLINAS TUESDAY THROUGH EARLY WEDNESDAY...BRINGING BRISK NORTHERLY WINDS AND CHILLY RAIN. A DRYING TREND IS EXPECTED BEGINNING ON WEDNESDAY...ACCOMPANIED BY A WARMING TREND INTO LATE NEXT WEEK AS HIGH PRESSURE BUILDS IN. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... AS OF 9:45 PM SUNDAY...ONE LAST LINE OF CONVECTION MOVING ACROSS THE CAPE FEAR REGION THIS EVENING...WHICH WILL BE FOLLOWED BY ISOLATED POP-UP SHOWERS THROUGH THE OVERNIGHT PERIOD. HAVE ADJUSTED THE FORECAST TO REFLECT THESE LATEST PRECIP TRENDS. LOOKS LIKE DANGER OF SEVERE STORMS IS OVER FOR THE NIGHT. RELEVANT PORTION OF DISCUSSION FROM THIS AFTERNOON FOLLOWS: DRIER AND COOLER AIR WILL SPILL SOUTHWARD OVERNIGHT...WITH RAIN MOVING OFF THE NC/SC COAST AROUND DAYBREAK. MINIMUM TEMPERATURES IN LOW 40S NORTH ZONES TO THE UPPER 40S NEAR 50 ACROSS THE VERY SOUTH IS ANTICIPATED. A FEW SHOWERS OR LIGHT RAIN MAY LINGER ALONG THE IMMEDIATE COAST AT 12Z(7AM)...BUT THE BULK OF SHOWERS WILL RESIDE OFFSHORE AT FIRST LIGHT OF MONDAY. && .SHORT TERM /6 AM THIS MORNING THROUGH TUESDAY NIGHT/... AS OF 300 PM SUNDAY...WEAK HIGH PRESSURE WILL BUILD DOWN FROM THE NORTH ON MONDAY INTO TUESDAY. DEEP NORTHWEST TO WESTERLY FLOW BEHIND DEPARTING COLD FRONT WILL ADVECT DRIER AND COOLER AIR INTO THE AREA THROUGH THE DAY ON MONDAY. ANY LINGERING MOISTURE AND CLOUDS MON MORNING WILL DISSIPATE GIVING WAY TO AFTERNOON SUNSHINE BUT TEMPS WILL REMAIN ALMOST 5 TO 10 DEGREES BELOW NORMAL IN COOL NORTHERLY FLOW ONLY REACHING CLOSER TO 60 FOR A HIGH TEMP. AS ONE SHORTWAVE RIDES AROUND A BROAD MID TO UPPER TROUGH THROUGH THE MID ATLANTIC STATES AND OFF SHORE ON MONDAY...ANOTHER MORE POTENT SHORTWAVE WILL DIG DOWN THE BACK END OF THE TROUGH INTO THE LOWER MISSISSIPPI VALLEY. SHALLOW COOL AIR WILL REMAIN LOCKED IN PLACE LOCALLY IN NORTHEAST FLOW HEADING INTO TUES AS SFC LOW DEVELOPS ALONG COLD FRONT MEANDERING BACK OVER THE MISSISSIPPI VALLEY. SURFACE LOW SLOWLY DEEPENS OVER THE GULF COAST AS THIS SHORTWAVE DIGS DOWN AND THEN TRAVERSES EAST REACHING JUST OFF THE SOUTHEAST COAST ON TUES. THE SFC LOW WILL STRENGTHEN AS IT MOVES NORTH FROM THE GA/FL COAST ON TUES PARALLELING THE CAROLINA COAST THROUGH TUES NIGHT. PCP WATER VALUES WILL REMAIN BELOW A HALF INCH IN DRY AIR THROUGH TUES MORNING. AS LOW APPROACHES THE SOUTHEAST COAST FROM THE WEST TUES MORNING...MID TO UPPER LEVEL FLOW WILL BACK TO THE S-SW AND INCREASE PUMPING MOISTURE INTO THE COASTAL CAROLINAS...BUT THE SFC FLOW WILL REMAIN NE. LOOKS LIKE THERE MAY BE A BRIEF PERIOD WHERE LOW LEVEL FLOW BACKS TO SW THROUGH TUES MORNING BUT OVERALL LOW LEVEL FLOW WILL REMAIN NORTHERLY ON BACK END OF LOW AS IT TRAVELS UP THE SOUTHEAST COASTAL WATERS. OVERALL AT THIS POINT IT LOOKS LIKE SFC LOW WILL REMAIN FAR ENOUGH OFF THE COAST AND WILL NOT DEEPEN APPRECIABLY UNTIL IT LIFTS NORTH TOWARD HATTERAS AND MID TO UPPER TROUGH LIFTS NORTH WITH IT TOWARD HATTERAS. AS FOR MID TO UPPER LEVELS DYNAMICS...BEST SHORTWAVE ENERGY ROTATES AROUND TO THE SOUTH AND EAST OF AREA AND BEST JET ENERGY REMAINS SOUTH THROUGH MOST OF TUES. WITH LATEST MODEL RUNS...NOT CONVINCED LOCAL AREA WILL EXPERIENCE A GREAT AMOUNT WITH THIS LOW. COUNTING ON COOL AND CLOUDY WEATHER TUES THROUGH WED MORNING WITH BEST CHC OF RAIN SPREADING NORTH THROUGH SOUTH CAROLINA AND PRIMARILY ALONG THE COAST BUT WILL NEED TO KEEP A CLOSE EYE ON THE EXACT TRACK AND TIMING OF SFC AND UPPER LEVEL FEATURES TO FINE TUNE. ALSO WITH POTENT MID TO UPPER LOW TRACKING OVER THE SOUTHEAST NOT COMFORTABLE TRYING TO FORECAST EXACT AREAS OF LIFT OR SUBSIDENCE AT THIS POINT AS LOW REMAINS WRAPPED TIGHT AND SMALL CHANGES COULD MAKE A LARGE DIFFERENCE IN FORECAST. SHOULD END UP BEING A LOWER END QPF EVENT FOR INLAND WITH GREATER AMOUNTS MAINLY ALIGNED ALONG THE COAST. TEMPERATURES WILL REMAIN BELOW CLIMO THROUGH THE PERIOD. DEPENDING ON HOW QUICKLY CLOUDS INCREASE ACROSS THE AREA WILL MAKE A DIFFERENCE IN HOW MUCH RADIATIONAL COOLING OCCURS TUES NIGHT. FOR NOW WILL COUNT ON DECENT RADIATIONAL COOLING BEFORE CLOUDS INCREASE TOWARD MORNING AND THEREFORE WILL KEEP LOWS IN THE 30S MOST PLACES. THIS COOL START COMBINED WITH COOL NORTHERLY FLOW WITH CLOUDS AND RAIN WILL MAKE FOR HIGH TEMPS WELL BELOW NORMAL...JUST MAKING IT INTO THE 50S MOST PLACES. LOW TEMPS ON TUES NIGHT WILL DEPEND ON HOW QUICKLY WE DRY AND COOL ON THE BACK END OF THE DEPARTING LOW. FOR NOW WILL GO WITH MID TO UPPER 30S. && .LONG TERM /WEDNESDAY THROUGH SUNDAY/... AS OF 300 PM SUNDAY...DEEPENING NOR`EASTER WILL BE PULLING AWAY AT THE START OF THE PERIOD. WITH THE ILM CWA ON THE DEPARTING EDGE OF THE STORM WEDNESDAY MORNING...HOW MUCH PRECIP REMAINS WILL BE DEPENDENT ON EXACT POSITION AND SPEED OF THE SURFACE LOW. ECMWF REMAINS THE SLOWEST/FURTHEST WEST WHILE THE CMC/GFS/GFS ENSEMBLES REMAIN EAST. THE ECMWF ENSEMBLE MEAN IS MORE IN LINE WITH THE GFS...SO WILL CONTINUE THE TREND OF LEANING TOWARDS THE GFS SOLUTION...BUT KEEPING SOME WEIGHT ON THE ECMWF DUE TO ITS SUPERIOR PERFORMANCE RECENTLY. WITH THIS IN MIND...AND KNOWING THAT THE BACK SIDE OF THE SYSTEM WILL LIKELY BE QUITE DRY...WILL KEEP INHERITED BASICALLY AS-IS...WITH SCHC POP EARLY WED ALONG THE NORTH/COAST...TRENDING TO DRY BY WED EVE. AS THE NOR`EASTER MOVES SLOWLY UP THE COAST...W/NW WINDS DEVELOP AND INCREASE THANKS TO THE TIGHTENING PRESSURE GRADIENT BETWEEN THE DEEPENING LOW AND ADVANCING HIGH. THIS MEANS THAT ALTHOUGH IT WILL BE DRY BY WED EVE AND THURSDAY...GUSTY WINDS AND CAA WILL KEEP TEMPS BELOW CLIMO. LATE IN THE WEEK AND INTO THE WKND...500MB RIDGE BULGES UP FROM THE GULF COAST AND SURFACE HIGH DRIFTS OVERHEAD. THESE WILL COMBINE TO CREATE WARM AND SUNNY WEATHER...WITH MAX TEMPS RISING TO WELL ABOVE CLIMO BY THE WKND...ALTHOUGH GOOD RADIATIONAL COOLING WILL STILL PERMIT MINS TO FALL TO THE LOW 40S EACH NIGHT. && .AVIATION /06Z MONDAY THROUGH FRIDAY/... AS OF 06Z...THE LINE OF SHOWERS AND TSTORMS HAS FINALLY MOVED OFFSHORE...AND NOW FOR THE REMAINDER OF THE OVERNIGHT... POST-FRONTAL -SHRA MAINLY VCSH TO AFFECT THE IMMEDIATE COAST UP TO A FEW HRS PRIOR TO DAYBREAK B4 MOVING OFF THE COAST FOR GOOD. HAVE STAYED CLOSER TO THE GFS AND RUC SOUNDINGS FOR BEING LESS AGGRESSIVE AND COVERAGE OF POST FRONTAL CEILINGS BELOW 1K FT. FOR THE MOST PART A 3K TO 6 K FT DECK OF CLOUDS WILL DOMINATE EARLY THIS MORNING...SCATTERING OUT LATER THIS MORNING AND AFTERNOON AS POST FRONTAL DRIER AIR AND COLD AIR ADVECTION INFILTRATES THE FA. VFR CONDITIONS TO PREVAIL FOR THE REMAINDER OF THE TAF PERIOD. POST FRONTAL NNE TO NE WINDS 8 TO 13 KNOTS WILL PREVAUIL WITH GUSTS 15 TO 20 KT POSSIBLE DURING DAYLIGHT HRS OF MONDAY. WINDS WILL BACK TO AROUND 5 KNOTS AFTER SUNSET. EXTENDED OUTLOOK...CHANCE OF STRATIFORM LIGHT TO MODERATE RAINS ...WITH ISOLATED HEAVIER SHOWERS AND POSSIBLE TSTORMS FOR THE COASTAL TERMS...FROM LATE MORNING TUESDAY THROUGH WEDNESDAY WITH OCCASIONAL PERIODS OF MVFR/IFR CONDITIONS POSSIBLE. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 10:30 PM SUNDAY...STRONG THUNDERSTORM ACTIVITY NOW CONFINED TO THE WATERS BEYOND 20 NM FROM SHORE. HAVE ADJUSTED FORECAST ACCORDINGLY. NO OTHER CHANGES TO THE FORECAST...PREVIOUS DISCUSSION FOLLOWS: CHANGEABLE WINDS EXPECTED OVER THE WATERS INTO TONIGHT AS A SURFACE LOW COMPLEX MOVES EAST AND OFFSHORE THIS EVENING...THEN PULLS A COLD FRONT SOUTHWARD OVER THE 0-20NM WATERS OVERNIGHT. WINDS AHEAD AND BEHIND THE FRONT WILL HAVE THE POTENTIAL TO INDUCE 20 KT GUSTS. THIS WILL BE PARTICULARLY TRUE LATE TONIGHT AS A NORTH SURGE OF WIND PUSHES SOUTHWARD OVER RELATIVELY MILD SEA SURFACE TEMPERATURES. SEAS WILL RUN MAINLY IN A 2-4 FOOT RANGE AND HIGHEST OFFSHORE AND AROUND THE OCEAN SHOALS. NO CAUTIONARY STATEMENTS OR ADVISORIES APPEAR TO BE NEEDED FOR NOW...BUT THE SEA WILL REMAIN BUMPY THROUGH DAYBREAK MONDAY DUE TO VARIABLE WIND DIRECTIONS TONIGHT...FOLLOWED BY MODERATE WIND- SPEEDS OVERNIGHT AND EARLY MONDAY. SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/... AS OF 300 PM SUNDAY...NORTHERLY FLOW WILL CONTINUE THROUGH THE PERIOD. THE WINDS WILL INCREASE THROUGH MONDAY MORNING IN COLD SURGE BEHIND DEPARTING COLD FRONT UP TO 15 TO 20 KTS. THIS WILL PUSH SEAS UP NEAR 4 TO 5 FT IN OUTER WATERS MON MORNING. THEN WEAK HIGH PRESSURE WILL RIDGE DOWN FROM THE NORTH MON THROUGH TUES AND GRADIENT RELAXES. THEREFORE WINDS DECREASE DOWN TO AROUND 15 KTS WITH SEAS SUBSIDING TO 2 TO 4 FT THROUGH TUES MORNING. WINDS AND SEAS WILL RAMP UP AGAIN LATE TUES THROUGH TUES NIGHT AS LOW PRESSURE SYSTEM DEEPENS AS IT RIDES UP THE OFF SHORE SOUTHEAST COASTAL WATERS. THE WINDS WILL BE HIGHLY DEPENDENT ON THE EXACT TRACK OF THIS LOW...BUT FOR NOW WILL KEEP LOW CENTER TO THE EAST OF LOCAL WATERS AS IT TRACKS UP FROM THE SOUTH REACHING JUST EAST OF LOCAL WATERS BY WED MORNING. THE INCREASING GRADIENT FLOW AND CONTINUED COOL NORTHERLY FLOW WILL PRODUCE A SHARP INCREASE IN WINDS AND SEAS TUES AFTERNOON THROUGH TUES NIGHT. WNA SHOWS SEAS REACHING UP NEAR 6 TO 7 FT IN OUTER WATERS TUES NIGHT. AT THIS POINT DO NOT HAVE WINDS EXCEEDING GALE THRESHOLD SO HAVE NO PLANS TO RAISE GALE WATCH. ALTHOUGH GALES ARE STILL POSSIBLE...LOOKING MORE LIKE A STRONG SCA EVENT WITH NORTHERLY FLOW OF 20 TO 25 KT AND SEAS BUILDING TO 4 TO 7 FT TUES NIGHT INTO WED MORNING. LONG TERM /WEDNESDAY THROUGH THURSDAY/... AS OF 300 PM SUNDAY...STRONG W/NW WINDS WITH 3-6 FT SEAS TO START THE PERIOD AS A DEEPENING NOR`EASTER SLOWLY PULLS AWAY UP THE COAST. WINDS WILL BE 15-25 KTS...HIGHEST ACROSS THE NORTHERN WATERS...AND A SMALL CRAFT ADVISORY MAY BE NEEDED FOR PART OF WEDNESDAY. THEREAFTER...AS THE LOW PRESSURE MOVES FURTHER AWAY WINDS SLOWLY DECREASE...BUT REMAIN 15-20 KTS THROUGH THURSDAY. WITH THE OFFSHORE WIND COMPONENT THOUGH...HIGHEST SEAS GET PUSHED OUT OF THE COASTAL WATERS SO WAVE AMPLITUDES FALL TO 2-3 FT THURSDAY. OFFSHORE WINDS CONTINUE FRIDAY BUT WITH EVEN WEAKER SPEEDS...AND SEAS DROP TO JUST 1-2 FT FOR THE END OF THE PERIOD. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...NONE. && $$ SYNOPSIS...JDW NEAR TERM...MJC/REK SHORT TERM...RGZ LONG TERM...JDW AVIATION...DCH/BJR
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
739 AM CST MON NOV 5 2012 .UPDATE... RADAR TRENDS SHOW THE PRECIPITATION IS SHUTTING DOWN QUICKER THAN PREVIOUSLY THOUGHT. ADDITIONALLY...THE DRY LOW LEVEL EASTERLY FLOW IS RESULTING IN BREAKS DEVELOPING IN THE OVERCAST. HOWEVER...AT THE SAME TIME SAID EASTERLY FLOW IS ADVECTING CLOUDS SOUTHWEST FROM LAKE MICHIGAN. WHICH SHOULD AFFECT PARTS OF THE EASTERN CWFA IN TIME. THUS SOME MINOR UPDATES TO THE FCST HAVE BEEN DONE TO REFLECT WHAT IS CURRENTLY GOING ON AND HOW IT SHOULD EVOLVE LATER. ..08.. && .PREV DISCUSSION... /ISSUED 543 AM CST MON NOV 5 2012/ UPDATE... OVERALL THE EARLIER THINKING STILL LOOKS ON TRACK. TRENDS FROM THE 06Z WRF AND RECENT RAP RUNS CONTINUE TO INDICATE THE DRY AIR WILL SLOWLY PUSH THE RAIN TO THE SOUTH AND WEST AS THE DAY PROGRESSES. SOME MINOR TWEEKS HAVE BEEN DONE TO THE FCST TO BETTER REFLECT THE COLD TEMPERATURES IN THE NORTHEAST/EAST PARTS OF THE CWFA. ..08.. AVIATION... VFR WX WILL BE SEEN THROUGH 12Z/06 AT KDBQ/KMLI AS DRY LOW LEVEL EASTERLY FLOW ADVECTS WEST OF THE MISSISSIPPI. AT KCID/KBRL MVFR CONDITIONS MAINLY FOR VSBY WILL BE SEEN THROUGH 18Z/05 BEFORE IMPROVING TO VFR WITH RAIN ENDING. YET ANOTHER STORM SYSTEM WILL AFFECT EASTERN IOWA/ILLINOIS WITH RAIN AFTER SUNRISE TUESDAY. CONDITIONS AFT 12Z/06 WILL START OUT AS VFR BUT MAY DETERIORATE TO MVFR DURING THE DAYLIGHT HOURS. ..08.. PREV DISCUSSION... /ISSUED 316 AM CST MON NOV 5 2012/ SYNOPSIS... 06Z SFC ANALYSIS HAS A LOW NEAR KFNB WITH A WARM FRONT ALONG THE KS/MO BORDER. A COLD FRONT RAN FROM THE LOW INTO NORTHEAST NEW MEXICO WHILE AN INVERTED TROF RAN FROM THE LOW INTO SOUTHWEST MINNESOTA. DEW POINTS WERE IN THE 20S ACROSS THE GREAT LAKES WITH 30S AND 40S OVER MUCH OF THE PLAINS AND MIDWEST. RADAR HAS WIDESPREAD RAIN AND DRIZZLE WAS ASSOCIATED WITH THE LOW AND INVERTED TROF ACROSS IOWA AND MISSOURI. SHORT TERM...TODAY AND TONIGHT... LOW LEVEL EASTERLY FLOW HAS RESULTED IN A WALL OF DRY AIR WHICH HAS STOPPED THE EASTWARD PROGRESSION OF THE PRECIPITATION. THE 850-700MB CONDENSATION PRESSURE DEFICITS IN COMBINATION WITH OVERALL FORCING FROM THE WRF AND RAP DEPICT QUITE WELL THE AREAL COVERAGE OF THE PRECIPITATION. USING THIS AS A GUIDE THE DRY EASTERLY FLOW WILL HELP PUSH THE PRECIPITATION TO THE SOUTH AND WEST DURING THE DAY WITH ONLY LINGERING DZ/RA ACROSS THE SOUTH THIRD BY LATE AFTERNOON. CLOUD COVER/PRECIPITATION WILL HELP HOLD DOWN TEMPERATURES TODAY WITH READINGS IN THE MID/UPPER 40S COMMON. MAINLY DRY CONDITIONS WILL BE SEEN ACROSS THE AREA THIS EVENING AS CONDENSATION PRESSURE DEFICITS REMAIN HIGH. BY LATE TONIGHT CONDENSATION PRESSURE DEFICITS COLLAPSE AGAIN AS THE NEXT SHORTWAVE APPROACHES. LIGHT RAIN/DRIZZLE MAY ENTER BUCHANAN COUNTY JUST PRIOR TO SUNRISE ON TUESDAY WHILE THE REMAINDER OF THE CWFA STAYS DRY. 08 LONG TERM...TUESDAY THROUGH NEXT SUNDAY... NEXT CLIPPER SYSTEM IS EXPECTED TO TRACK THROUGH THE GREAT LAKES TUE-TUE NGT. MOISTURE IS MARGINAL BUT DYNAMICS IN FORM OF GOOD UPPER DIFFLUENCE... MID LEVEL FRONTOGENESIS AND DIVERGENCE WITH LEFT EXIT REGION OF 100-120+ KT H3 JET MORE THAN ADEQUATE TO OVERCOME AND GENERATE BAND(S) OF LIGHT RAIN OR SHOWERS TUE AM BEFORE SHIFTING EAST. SPEED OF SYSTEM AND MARGINAL MOISTURE SUPPORTS LIGHT AMOUNTS OF A FEW HUNDREDTHS TO AROUND 0.1 INCH MOST AREAS. BANKING ON AT LEAST PARTIAL SUNSHINE W/SW SECTIONS TUE AFTN IN WAKE OF PASSING SYSTEM TO PUSH HIGHS INTO THE 50S... WITH 40S LIKELY ELSEWHERE WITH COOLEST READINGS NORTHEAST CWA. THIS CLIPPER SYSTEM LOOKS TO PHASE WITH THE SYSTEM THAT IS MOVING THROUGH EARLY THIS AM TO PRODUCE CLASSIC NOR`EASTER... WITH STRONG LOW MOVING UP ALONG THE NORTHEAST COAST UNFORTUNATELY POUNDING AREAS RECOVERING FROM HURRICANE SANDY WITH MORE HEAVY PCPN AND STRONG WINDS WED-THU. WED-WED NGT... INCOMING SUBSIDENCE WITH SFC RIDGE BUILDING IN WAKE OF DEPARTING CLIPPER SYSTEM TO PROVIDE DRY WX WITH DECREASING CLOUDS. TEMPS REMAIN BELOW NORMAL WITH HIGHS IN THE 40S TO L50S... AND LOWS IN THE 20S TO L30S. THU-FRI... SFC RIDGE SLIDES EAST EARLY IN THE PERIOD WITH RETURN FLOW DEVELOPING. ALOFT... UPPER RIDGE AMPLIFIES OVERHEAD AND ESPECIALLY JUST DOWNSTREAM OVER THE OHIO VLY IN RESPONSE TO LARGE TROUGH MOVING ACROSS THE WESTERN CONUS. PERSISTENT WARM ADVECTION ON STRENGTHENING LOW-MID LEVEL SOUTHERLY WINDS SUPPORT MODERATING TEMPS NEAR TO ABOVE NORMAL. SAT-SUN... PATTERN SET TO UNDERGO CHANGE LEADING TO UNSETTLED/WET REGIME FOR THE AREA. STILL UNCERTAINTIES WITH MODELS HANDLING OF ENERGY AS IT EJECTS FROM THE WESTERN CONUS... WITH MAIN IMPACTS TO TIMING OF FRONT AND PRECIPITATION. GENERAL CONSENSUS ATTM IS TO MOVE STRONG COLD FRONT THROUGH THE AREA ON SUN WITH WIDESPREAD RAIN OCCURRING MAINLY POST FRONTAL. LOCATION OF JET DOES APPEAR FAVORABLE FOR AT LEAST ISOLD TO SCT STORMS ATTM... BUT BEING LATE DAY 6-7 AND LIKELIHOOD FOR ADDITIONAL CHANGES WITH MODELS HANDLING OF ENERGY HAVE OPTED TO KEEP PTYPE AS SHOWERS FOR NOW. STRENGTH OF FORCING ALONG WITH GULF MOISTURE FEED CONTINUES TO SUPPORT MODERATE TO LOCALLY HEAVY RAINS OF 0.5 TO 1.5 INCHES. COULD BE HIGHER AMOUNTS ESPECIALLY IF WAVE DEVELOPS ON FRONT AS SHOWN BY 00Z GFS. THIS IS SOME OF THE UNCERTAINTY TO BE RESOLVED IN THE COMING DAYS. TEMPS LOOK TO COME CRASHING BACK DOWN TO BELOW NORMAL BY EARLY NEXT WEEK IN WAKE OF STRONG COLD FRONTAL PASSAGE. MCCLURE && .DVN WATCHES/WARNINGS/ADVISORIES... IA...NONE. IL...NONE. MO...NONE. && $$
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
543 AM CST MON NOV 5 2012 .UPDATE... OVERALL THE EARLIER THINKING STILL LOOKS ON TRACK. TRENDS FROM THE 06Z WRF AND RECENT RAP RUNS CONTINUE TO INDICATE THE DRY AIR WILL SLOWLY PUSH THE RAIN TO THE SOUTH AND WEST AS THE DAY PROGRESSES. SOME MINOR TWEEKS HAVE BEEN DONE TO THE FCST TO BETTER REFLECT THE COLD TEMPERATURES IN THE NORTHEAST/EAST PARTS OF THE CWFA. ..08.. && .AVIATION... VFR WX WILL BE SEEN THROUGH 12Z/06 AT KDBQ/KMLI AS DRY LOW LEVEL EASTERLY FLOW ADVECTS WEST OF THE MISSISSIPPI. AT KCID/KBRL MVFR CONDITIONS MAINLY FOR VSBY WILL BE SEEN THROUGH 18Z/05 BEFORE IMPROVING TO VFR WITH RAIN ENDING. YET ANOTHER STORM SYSTEM WILL AFFECT EASTERN IOWA/ILLINOIS WITH RAIN AFTER SUNRISE TUESDAY. CONDITIONS AFT 12Z/06 WILL START OUT AS VFR BUT MAY DETERIORATE TO MVFR DURING THE DAYLIGHT HOURS. ..08.. && .PREV DISCUSSION... /ISSUED 316 AM CST MON NOV 5 2012/ SYNOPSIS... 06Z SFC ANALYSIS HAS A LOW NEAR KFNB WITH A WARM FRONT ALONG THE KS/MO BORDER. A COLD FRONT RAN FROM THE LOW INTO NORTHEAST NEW MEXICO WHILE AN INVERTED TROF RAN FROM THE LOW INTO SOUTHWEST MINNESOTA. DEW POINTS WERE IN THE 20S ACROSS THE GREAT LAKES WITH 30S AND 40S OVER MUCH OF THE PLAINS AND MIDWEST. RADAR HAS WIDESPREAD RAIN AND DRIZZLE WAS ASSOCIATED WITH THE LOW AND INVERTED TROF ACROSS IOWA AND MISSOURI. SHORT TERM...TODAY AND TONIGHT... LOW LEVEL EASTERLY FLOW HAS RESULTED IN A WALL OF DRY AIR WHICH HAS STOPPED THE EASTWARD PROGRESSION OF THE PRECIPITATION. THE 850-700MB CONDENSATION PRESSURE DEFICITS IN COMBINATION WITH OVERALL FORCING FROM THE WRF AND RAP DEPICT QUITE WELL THE AREAL COVERAGE OF THE PRECIPITATION. USING THIS AS A GUIDE THE DRY EASTERLY FLOW WILL HELP PUSH THE PRECIPITATION TO THE SOUTH AND WEST DURING THE DAY WITH ONLY LINGERING DZ/RA ACROSS THE SOUTH THIRD BY LATE AFTERNOON. CLOUD COVER/PRECIPITATION WILL HELP HOLD DOWN TEMPERATURES TODAY WITH READINGS IN THE MID/UPPER 40S COMMON. MAINLY DRY CONDITIONS WILL BE SEEN ACROSS THE AREA THIS EVENING AS CONDENSATION PRESSURE DEFICITS REMAIN HIGH. BY LATE TONIGHT CONDENSATION PRESSURE DEFICITS COLLAPSE AGAIN AS THE NEXT SHORTWAVE APPROACHES. LIGHT RAIN/DRIZZLE MAY ENTER BUCHANAN COUNTY JUST PRIOR TO SUNRISE ON TUESDAY WHILE THE REMAINDER OF THE CWFA STAYS DRY. 08 LONG TERM...TUESDAY THROUGH NEXT SUNDAY... NEXT CLIPPER SYSTEM IS EXPECTED TO TRACK THROUGH THE GREAT LAKES TUE-TUE NGT. MOISTURE IS MARGINAL BUT DYNAMICS IN FORM OF GOOD UPPER DIFFLUENCE... MID LEVEL FRONTOGENESIS AND DIVERGENCE WITH LEFT EXIT REGION OF 100-120+ KT H3 JET MORE THAN ADEQUATE TO OVERCOME AND GENERATE BAND(S) OF LIGHT RAIN OR SHOWERS TUE AM BEFORE SHIFTING EAST. SPEED OF SYSTEM AND MARGINAL MOISTURE SUPPORTS LIGHT AMOUNTS OF A FEW HUNDREDTHS TO AROUND 0.1 INCH MOST AREAS. BANKING ON AT LEAST PARTIAL SUNSHINE W/SW SECTIONS TUE AFTN IN WAKE OF PASSING SYSTEM TO PUSH HIGHS INTO THE 50S... WITH 40S LIKELY ELSEWHERE WITH COOLEST READINGS NORTHEAST CWA. THIS CLIPPER SYSTEM LOOKS TO PHASE WITH THE SYSTEM THAT IS MOVING THROUGH EARLY THIS AM TO PRODUCE CLASSIC NOR`EASTER... WITH STRONG LOW MOVING UP ALONG THE NORTHEAST COAST UNFORTUNATELY POUNDING AREAS RECOVERING FROM HURRICANE SANDY WITH MORE HEAVY PCPN AND STRONG WINDS WED-THU. WED-WED NGT... INCOMING SUBSIDENCE WITH SFC RIDGE BUILDING IN WAKE OF DEPARTING CLIPPER SYSTEM TO PROVIDE DRY WX WITH DECREASING CLOUDS. TEMPS REMAIN BELOW NORMAL WITH HIGHS IN THE 40S TO L50S... AND LOWS IN THE 20S TO L30S. THU-FRI... SFC RIDGE SLIDES EAST EARLY IN THE PERIOD WITH RETURN FLOW DEVELOPING. ALOFT... UPPER RIDGE AMPLIFIES OVERHEAD AND ESPECIALLY JUST DOWNSTREAM OVER THE OHIO VLY IN RESPONSE TO LARGE TROUGH MOVING ACROSS THE WESTERN CONUS. PERSISTENT WARM ADVECTION ON STRENGTHENING LOW-MID LEVEL SOUTHERLY WINDS SUPPORT MODERATING TEMPS NEAR TO ABOVE NORMAL. SAT-SUN... PATTERN SET TO UNDERGO CHANGE LEADING TO UNSETTLED/WET REGIME FOR THE AREA. STILL UNCERTAINTIES WITH MODELS HANDLING OF ENERGY AS IT EJECTS FROM THE WESTERN CONUS... WITH MAIN IMPACTS TO TIMING OF FRONT AND PRECIPITATION. GENERAL CONSENSUS ATTM IS TO MOVE STRONG COLD FRONT THROUGH THE AREA ON SUN WITH WIDESPREAD RAIN OCCURRING MAINLY POST FRONTAL. LOCATION OF JET DOES APPEAR FAVORABLE FOR AT LEAST ISOLD TO SCT STORMS ATTM... BUT BEING LATE DAY 6-7 AND LIKELIHOOD FOR ADDITIONAL CHANGES WITH MODELS HANDLING OF ENERGY HAVE OPTED TO KEEP PTYPE AS SHOWERS FOR NOW. STRENGTH OF FORCING ALONG WITH GULF MOISTURE FEED CONTINUES TO SUPPORT MODERATE TO LOCALLY HEAVY RAINS OF 0.5 TO 1.5 INCHES. COULD BE HIGHER AMOUNTS ESPECIALLY IF WAVE DEVELOPS ON FRONT AS SHOWN BY 00Z GFS. THIS IS SOME OF THE UNCERTAINTY TO BE RESOLVED IN THE COMING DAYS. TEMPS LOOK TO COME CRASHING BACK DOWN TO BELOW NORMAL BY EARLY NEXT WEEK IN WAKE OF STRONG COLD FRONTAL PASSAGE. MCCLURE && .DVN WATCHES/WARNINGS/ADVISORIES... IA...NONE. IL...NONE. MO...NONE. && $$
AREA FORECAST DISCUSSION
NWS WICHITA KS
534 AM CST MON NOV 5 2012 .AVIATION...12Z TAFS KRSL/KSLN/KHUT/KICT/KCNU POTENTIAL FOR MVFR CEILINGS AT ALL SITES DURING THE DAYLIGHT HOURS AS LOW LEVEL COLD AIR ADVECTION SPREADS LOW CLOUDS INTO THE AREA. NAM WAS STRUGGLING WITH WESTERN EXTEND OF CURRENT LOW CLOUDS...WITH CURRENT RUC LOOKING MUCH BETTER. WILL BASE CLOUD FORECAST ON THE RUC LOW LEVEL MOISTURE PROFILES THIS MORNING...AND THEN TRANSITION TO NAM DURING THE AFTERNOON. WILL GO BROKEN-OVERCAST AT ALL SITES...BUT COULD SEE KRSL/KHUT ONLY GOING BROKEN-OVERCAST FOR A BRIEF PERIOD. CEILINGS SHOULD INCREASE A TAD DURING THE DAY. GUSTY NORTH WINDS AND CLOUDS SHOULD BOTH DIMINISH THIS AFTERNOON. HOWEVER ANOTHER WEAK SHORTWAVE WILL LIKELY SPREAD A MID LEVEL CLOUD DECK ACROSS ALL SITES OVERNIGHT. -HOWERTON && .PREV DISCUSSION... /ISSUED 315 AM CST MON NOV 5 2012/ DISCUSSION... THE MAIN FORECAST CHALLENGES ARE THE TEMPERATURES TOWARD THE END OF THE WORK WEEK AND THE COLD FRONTAL PASSAGE SATURDAY. SYNOPSIS: MUCH LIKE THE LAST FEW DAYS THE CONUS WEATHER PATTERN HAS CHANGED LITTLE...WITH A LARGE...BROAD TROUGH ACROSS THE EASTERN HALF OF THE COUNTRY AND A RIDGE ACROSS THE WESTERN HALF. THERE ARE MULTIPLE DISTURBANCES MOVING AROUND THE TROUGH OVER THE EAST. ONE OF THE DISTURBANCES IS DIVING ACROSS THE EASTERN HALVES OF NEBRASKA AND KANSAS...AND THIS WAVE HAS PUSHED A WEAK FRONT THROUGH THE AREA. WINDS ARE BECOMING NORTHWESTERLY. THE WINDS THIS MORNING AND THE CLOUD COVER ARE HELPING TO KEEP TEMPERATURES A BIT WARMER. TODAY - WEDNESDAY: THE WORK WEEK WILL HAVE A TRANQUIL BEGINNING. THE FRONT THAT WENT THROUGH LATE LAST NIGHT/EARLY THIS MORNING WILL CONTINUE TO PUSH EASTWARD WITH HIGH PRESSURE QUICKLY SLIDING IN BEHIND IT. THE UPPER PV WAVE IS STILL CLOSE ENOUGH THAT SCATTERED SHOWERS ARE POSSIBLE ACROSS EXTREME SOUTHEASTERN KANSAS THIS MORNING. NOT EXPECTING MUCH IN THE WAY OF ACCUMULATION...BUT CANNOT RULE OUT SPRINKLES AND A SHOWER OR TWO...ESPECIALLY AFTER SPRITZ AND SPRINKLES WERE REPORTED SUNDAY AFTERNOON ACROSS THE AREA. AFTER THE CHANCE THIS MORNING...THE FORECAST REMAINS DRY UNTIL THE END OF THE WEEK. ANOTHER DISTURBANCE WILL DIVE SOUTHEAST INTO THE BASE OF THE TROUGH TUESDAY NIGHT/WEDNESDAY AND WILL PULL YET ANOTHER VERY WEAK FRONT ACROSS THE AREA...MAINLY RESULTING IN A WIND SHIFT. SURFACE HIGH PRESSURE WILL BUILD AND SLIDE EASTWARD WEDNESDAY. TEMPERATURES WILL BE VERY SEASONAL...WITH THE COOLEST TEMPS TODAY AND WARMING INTO THE 70S FOR TUESDAY AND WEDNESDAY...5 TO 10 DEGREES ABOVE NORMAL FOR EARLY NOVEMBER. THURSDAY - SUNDAY: THIS PERIOD CONTINUES TO BE THE MOST INTERESTING OF THE FORECAST WITH A LARGE CHANGE COMING TO THE PLAINS. THE UPPER RIDGE OVER THE WEST WILL TRANSLATE EASTWARD OVER THE PLAINS WITH A LARGE POTENT PV ANOMALY DIVING SOUTH FROM ALASKA APPROACHING FROM THE WEST. THE MEDIUM RANGE GUIDANCE HAS BEEN IN GOOD AGREEMENT FOR THE LAST FEW DAYS REGARDING THIS SYSTEM WHICH GIVES CONFIDENCE TO THE FORECAST. THE SOUTHWESTERLY UPPER LEVEL FLOW WILL AID LEE TROUGHING TO DEEPEN WITH STOUT GRADIENT WINDS EXPECTED FROM THURSDAY - SATURDAY. THE COMBINATION OF THE WARM AIR ADVECTION AND STRONG SOUTH WINDS WILL HELP TEMPERATURES RISE 10-20 DEGREES ABOVE NORMAL...WITH SOME AREAS POSSIBLY REACHING THE LOW 80S...ALTHOUGH HAVE KEPT THE FORECASTED TEMPS IN THE UPPER 70S FOR NOW. RECORDS LOOK SAFE FOR THURSDAY...BUT THEY COULD BE IN JEOPARDY FOR FRIDAY AND SATURDAY AT A FEW LOCATIONS IF THINGS STAY ON TRACK. THE COLD FRONT IS EXPECTED TO TRAVERSE THE AREA SATURDAY NIGHT/SUNDAY MORNING...AND FOR BEING AT 144+ HOURS...THE GUIDANCE IS IN SHOCKINGLY GOOD AGREEMENT ON TIMING. HOWEVER...DESPITE THE SIMILARITIES THERE ARE SOME DIFFERENCES IN THE GUIDANCE...ESPECIALLY REGARDING THE PRECIPITATION POTENTIAL. THE GFS CONTINUES TO BE MORE BULLISH WITH WARM SECTOR PRECIP THAN THE ECMWF. HAVE KEPT SLIGHTS FOR FRIDAY AHEAD OF THE FRONT...BUT THINK THE MAJORITY AND BEST CHANCE WE HAVE FOR PRECIPITATION WILL BE WITH THE CONVERGENCE ALONG THE FRONT AND THE MAIN UPPER DYNAMICS AS IT MOVES ACROSS THE AREA. REGARDLESS...THIS IS THE BEST CHANCE FOR RAIN IN THE FORECAST. THIS SYSTEM WILL BRING SIGNIFICANT CHANGES WITH ARCTIC AIR MOVING INTO PLACE BEHIND THE FRONTAL PASSAGE. TEMPERATURES SATURDAY NIGHT AND SUNDAY WILL BE SIGNIFICANTLY COLDER...HIGHS IN THE 30S/40S AND LOWS IN THE 20S. WITH THESE TEMPS AND PRECIPITATION POTENTIAL...SOME AREAS OF KANSAS MAY SEE SNOW WITH THIS SYSTEM. BILLINGS FIRE WEATHER... DRY CONDITIONS AND GUSTY WINDS WILL CAUSE FIRE WEATHER TO BE A CONCERN...ESPECIALLY TOWARD THE END OF THE WEEK. STRONG NORTHWESTERLY WINDS AND LOW DEWPOINTS TODAY WILL CAUSE VERY HIGH FIRE DANGER TO BE A CONCERN ACROSS MUCH OF CENTRAL AND SOUTH CENTRAL KANSAS. A POTENT WEATHER SYSTEM WILL APPROACH FOR THE WEEKEND AND LEE TROUGHING WILL CAUSE GRADIENT WINDS TO INCREASE THURSDAY THROUGH SATURDAY. VERY HIGH GRASSLAND FIRE DANGER IS EXPECTED THURSDAY THROUGH SATURDAY. SOME AREAS OF CENTRAL KANSAS WILL HAVE THE POTENTIAL FOR EXTREME GRASSLAND FIRE DANGER SATURDAY AHEAD OF THE FRONTAL PASSAGE. THINGS COULD CHANGE WITH THE FORECAST AND TIMING...SO KEEP AN EYE ON THINGS. BILLINGS CLIMATE... RECORD HIGHS FOR THURSDAY NOVEMBER 8TH, 2012 WICHITA....86 IN 2006 RUSSELL....89 IN 2006 SALINA.....89 IN 2006 CHANUTE....84 IN 2006 RECORD HIGHS FOR FRIDAY NOVEMBER 9TH, 2012 WICHITA....82 IN 2006 RUSSELL....78 IN 1999 SALINA.....80 IN 1999 CHANUTE....82 IN 2006 RECORD HIGHS FOR SATURDAY NOVEMBER 10TH, 2012 WICHITA....77 IN 1927 RUSSELL....78 IN 1956 SALINA.....82 IN 1927 CHANUTE....78 IN 1911 BILLINGS AVIATION...06Z TAFS KRSL/KSLN/KHUT/KICT/KCNU AT THE MID-NGT HOUR A SLOW SE-MOVG COLD FRONT WAS KNOCKING ON THE DOOR AT KSLN & KHUT. NW WINDS IN THE FRONT`S WAKE WERE ONLY 5-10KTS & HAVE THEREFORE EASED ON WIND THROTTLE FOR ALL 5 TERMINALS FOR THE REMAINDER OF THE NGT. THE MORE SIGNIFICANT CHANGE IS THAT MVFR CIGS (~2,500FT) WILL VENTURE ACROSS THE KRSL & KSLN TERMINALS FROM 12Z-17Z. WITH THE SE MOVEMENT OF THE 925-850MB LOW THE MVFR CIGS SHOULD REMAIN NE OF THE KICT & KHUT TERMINALS. NW WINDS SUSTAINED ~17KTS/22MPH WITH GUSTS THAT MAY REACH ~25KTS ARE LIKELY FOR ALL 5 TERMINALS FROM ~15Z TIL LATE IN AFTERNOON. ES && .PRELIMINARY POINT TEMPS/POPS... WICHITA-KICT 59 35 72 38 / 0 0 0 0 HUTCHINSON 57 34 71 37 / 0 0 0 0 NEWTON 54 34 68 37 / 10 0 0 0 ELDORADO 56 33 69 36 / 10 0 0 0 WINFIELD-KWLD 59 35 70 39 / 0 0 0 0 RUSSELL 59 34 69 35 / 0 0 0 0 GREAT BEND 60 34 70 38 / 0 0 0 0 SALINA 57 35 69 37 / 0 0 0 0 MCPHERSON 56 34 71 37 / 0 0 0 0 COFFEYVILLE 60 36 67 37 / 20 0 0 0 CHANUTE 55 36 65 36 / 20 0 0 0 IOLA 53 37 64 37 / 20 0 0 0 PARSONS-KPPF 58 34 66 34 / 20 0 0 0 && .ICT WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
729 AM EST MON NOV 5 2012 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 525 AM EST MON NOV 5 2012 WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL RIDGE INTO THE WRN CONUS AND A TROUGH OVER THE CENTRAL AND EAST. WEAK NRLY FLOW PREVAILED ACROSS THE NRN GREAT LAKES BTWN A CLOSED LOW OVER NRN QUEBEC AND A SHRTWV TROUGH INTO NW MISSOURI. A STRONGER UPSTREAM SHRTWV WAS MOVING QUICKLY EASTWARD INTO SRN ALBERTA. AT THE SFC...A RIDGE EXTENDED FROM NRN ONTARIO INTO CNTRL WI RESULTING IN WEAK ENE FLOW THROUGH UPPER MI. IR LOOP SHOWED LOW CLOUDS PERSISTING OVER THE CWA WITH MOISTURE TRAPPED BELOW THE INVERSION AROUND 2K-3K FT. A PATCH OF CLEAR SKIES NEAR ANJ/CIU HAS SLID TO THE SW AND MOSTLY FILLED BACK IN. RADAR INDICATED THAT THE ISOLD -SHSN/FLURRIES HAD AT LEAST TEMPORARILY ENDED. THE SURFACE HIGH WILL DRIFT TO THE SOUTHEAST ACROSS THE UPPER GREAT LAKES REGION. THE LIGHT ERLY 925 MB WINDS MAY ALLOW FOR SOME CLEARING OVER THE ERN CWA TODAY WITH DOWNSLOPE FLOW FROM N OF THE SAULT. IN ADDITION...DAYTIME MIXING SHOULD ALSO HELP ERODE THE CLOUDS. OVER THE WEST...UPSLOPE FLOW SHOULD HELP TO MAINTAIN THE OVERCAST CONDITIONS. 900 MB TEMPS AROUND -8C WILL PROVIDE ENOUGH INSTABILITY FOR THE CONTINUED POTENTIAL OF ISOLD -SHSN W AND N OF MARQUETTE INTO THE KEWEENAW THIS MORNING. BY AFTERNOON...WINDS WILL BECOME LIGHT SRLY...ENDING ANY -SHSN CHANCES. THE LOW CLOUDS WILL AGAIN KEEP TEMPS FROM CLIMBING BEYOND THE MID AND UPPER 30S. TONIGHT...PCPN ASSOCIATED WITH THE SHORTWAVE TROUGH DIVING FROM SRN MANITOBA INTO THE UPPER MS VALLEY WILL SPREAD INTO WRN LAKE SUPERIOR AND POSSIBLY INTO THE WEST HALF OF UPPER MI. NAM WET-BULB ZERO HEIGHT SUGGEST THAT PCPN STARTING OUT AS SNOW COULD BEGIN CHANGING OVER TO RAIN OVER THE WEST. THE BEST CHANCE FOR ANY MEASURABLE PCPN WILL ONLY BE OVER THE FAR WEST FROM IWD-CMX. ANY SNOW AMOUNTS WOULD ONLY AMOUNT TO A LIGHT COATING (FEW TENTHS) OVER THE HIGHER TERRAIN. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 525 AM EST MON NOV 5 2012 FCST MODELS HAVE SLOWED DOWN THE PROGRESS OF THE NEXT SYSTEM INFLUENCING THE UPPER GREAT LAKES...BY ROUGHLY 2-3HRS IN THE PAST COUPLE OF RUNS. EXPECT THE LOW TO PUSH ACROSS UPPER MICHIGAN TUESDAY AFTERNOON...AND SLOWLY EXIT TO THE SOUTHEAST TUESDAY NIGHT...MERGING WITH THE STRONGER LOW OFF THE MID ATLANTIC COAST ON WEDNESDAY. ONE TO TWO TENTH OF AN INCH OF LIQUID IS EXPECTED...MAINLY IN THE FORM OF RAIN. THE COOLER HIGHER ELEVATIONS OF N CENTRAL UPPER MI THAT SHOULD TOP OUT IN THE MID 30S TUESDAY SHOULD STAY IN THE MOSTLY IN THE FORM OF SNOW. STILL HAVE HALF OF AN INCH TO RIGHT AROUND AN INCH OF NEW SNOW FORECAST THROUGH TUESDAY EVENING...AS THE DGZ AROUND 600MB IS BRIEFLY ACCOMPANIED BY ENOUGH MOISTURE TO PRODUCE ACCUMULATING SNOW. S SFC TO 850MB WINDS OF 15-25KTS OVER N CENTRAL TO NE UPPER MI TUESDAY SHOULD KEEP DOWNSLOPE AREAS A COUPLE DEGREES WARMER. GIVEN THE FAIRLY CONSISTENT MODEL RUNS...A BLEND SEEMS REASONABLE FOR MUCH OF THE PERIOD. DRIER AIR WILL SLOWLY WORK IN WEDNESDAY AND STAY THROUGH AT LEAST THURSDAY NIGHT AS HIGH PRESSURE REMAINS IN CONTROL AT THE SFC AND ALOFT. SW FLOW WILL BE ON THE INCREASE AGAIN FRIDAY AFTERNOON AND EVENING AS THE SFC RIDGE WEAKENS OVER THE CWA AND THE APEX OF THE 500MB RIDGE EDGES JUST TO OUR E. WITH SOME OF THE WARMEST AIR WE HAVE HAD OVER THE CWA IN A COUPLE OF WEEKS /850MB TEMPS POSSIBLY BU TO 12C AT 00Z SUN OFF THE NEW 11/00Z ECMWF/. WITH ALL THE WARM AIR AND INCREASED LAPSE RATES KEPT THE POTENTIAL FOR TS SATURDAY INTO SUNDAY...BUT DID A BIT OF TAILORING TO ALIGN BETTER WITH THE LATEST MODEL DATA. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING) ISSUED AT 723 AM EST MON NOV 5 2012 SAW/CMX...EXPECT MVFR CONDITIONS TO DOMINATE THROUGH THIS MORNING WITH SLOWLY VEERING UPSLOPE NE TO E FLOW ON THE SOUTHERN FLANK OF HIGH PRES SLIDING SLOWLY SEWD THROUGH NW ONTARIO AND UNDER SHARP LOW SUBSIDENCE. ALTHOUGH THERE COULD BE A FEW -SHSN MAINLY AT CMX WITH MORE FAVORABLE UPSLOPE FLOW...THE LOW INVERSION BASE WILL LIMIT THE INTENSITY OF THIS PCPN AND ANY RESTRICTION TO VSBY. BY THIS AFTERNOON...THE COMBINATION OF DIURNAL HEATING AND WIND SHIFT TO THE SOUTH SHOULD ALLOW A RETURN OF VFR CONDITIONS THAT WILL PERSIST UNTIL LATE TONIGHT. IWD...LOOK FOR MVFR CIGS TO PERSIST UNTIL LATER THIS MORNING WHEN DAYTIME HEATING/WSHFT TO A DOWNSLOPING S DIRECTION WL BRING A RETURN OF VFR CONDITIONS BY MON AFTN THAT PERSISTS THROUGH THIS EVENING. MVFR CIGS ARE EXPECTED BY LATE TONIGHT AT IWD/CMX WHEN RAIN POSSIBLY MIXED WITH SNOW DEVELOPS. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 525 AM EST MON NOV 5 2012 AS HIGH PRESSURE OVER NORTHWEST ONTARIO SLIDES SOUTHEAST THROUGH THE UPPER GREAT LAKES TODAY...EXPECT WINDS TO BE LIGHT AND LESS THAN 20KTS. A LOW PRESSURE SYSTEM MOVING THROUGH CENTRAL CANADA ON TUESDAY WILL SWEEP A SURFACE TROUGH ACROSS THE UPPER GREAT LAKES REGION AND BRING INCREASING SOUTHWESTERLY WINDS TO 20-30 KTS. A WEAK HIGH PRESSURE RIDGE WILL THEN SLIDE INTO THE UPPER GREAT LAKES WEDNESDAY AFTERNOON AND REMAIN INTO FRIDAY. A 29.5 INCH LOW PRESSURE SYSTEM DEVELOPING IN THE CENTRAL PLAINS ON FRIDAY IS EXPECTED TO LIFT NORTH INTO THE UPPER MISSISSIPPI VALLEY BY SATURDAY NIGHT. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLB LONG TERM...KF AVIATION...JLB MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
526 AM EST MON NOV 5 2012 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 525 AM EST MON NOV 5 2012 WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL RIDGE INTO THE WRN CONUS AND A TROUGH OVER THE CENTRAL AND EAST. WEAK NRLY FLOW PREVAILED ACROSS THE NRN GREAT LAKES BTWN A CLOSED LOW OVER NRN QUEBEC AND A SHRTWV TROUGH INTO NW MISSOURI. A STRONGER UPSTREAM SHRTWV WAS MOVING QUICKLY EASTWARD INTO SRN ALBERTA. AT THE SFC...A RIDGE EXTENDED FROM NRN ONTARIO INTO CNTRL WI RESULTING IN WEAK ENE FLOW THROUGH UPPER MI. IR LOOP SHOWED LOW CLOUDS PERSISTING OVER THE CWA WITH MOISTURE TRAPPED BELOW THE INVERSION AROUND 2K-3K FT. A PATCH OF CLEAR SKIES NEAR ANJ/CIU HAS SLID TO THE SW AND MOSTLY FILLED BACK IN. RADAR INDICATED THAT THE ISOLD -SHSN/FLURRIES HAD AT LEAST TEMPORARILY ENDED. THE SURFACE HIGH WILL DRIFT TO THE SOUTHEAST ACROSS THE UPPER GREAT LAKES REGION. THE LIGHT ERLY 925 MB WINDS MAY ALLOW FOR SOME CLEARING OVER THE ERN CWA TODAY WITH DOWNSLOPE FLOW FROM N OF THE SAULT. IN ADDITION...DAYTIME MIXING SHOULD ALSO HELP ERODE THE CLOUDS. OVER THE WEST...UPSLOPE FLOW SHOULD HELP TO MAINTAIN THE OVERCAST CONDITIONS. 900 MB TEMPS AROUND -8C WILL PROVIDE ENOUGH INSTABILITY FOR THE CONTINUED POTENTIAL OF ISOLD -SHSN W AND N OF MARQUETTE INTO THE KEWEENAW THIS MORNING. BY AFTERNOON...WINDS WILL BECOME LIGHT SRLY...ENDING ANY -SHSN CHANCES. THE LOW CLOUDS WILL AGAIN KEEP TEMPS FROM CLIMBING BEYOND THE MID AND UPPER 30S. TONIGHT...PCPN ASSOCIATED WITH THE SHORTWAVE TROUGH DIVING FROM SRN MANITOBA INTO THE UPPER MS VALLEY WILL SPREAD INTO WRN LAKE SUPERIOR AND POSSIBLY INTO THE WEST HALF OF UPPER MI. NAM WET-BULB ZERO HEIGHT SUGGEST THAT PCPN STARTING OUT AS SNOW COULD BEGIN CHANGING OVER TO RAIN OVER THE WEST. THE BEST CHANCE FOR ANY MEASURABLE PCPN WILL ONLY BE OVER THE FAR WEST FROM IWD-CMX. ANY SNOW AMOUNTS WOULD ONLY AMOUNT TO A LIGHT COATING (FEW TENTHS) OVER THE HIGHER TERRAIN. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 525 AM EST MON NOV 5 2012 FCST MODELS HAVE SLOWED DOWN THE PROGRESS OF THE NEXT SYSTEM INFLUENCING THE UPPER GREAT LAKES...BY ROUGHLY 2-3HRS IN THE PAST COUPLE OF RUNS. EXPECT THE LOW TO PUSH ACROSS UPPER MICHIGAN TUESDAY AFTERNOON...AND SLOWLY EXIT TO THE SOUTHEAST TUESDAY NIGHT...MERGING WITH THE STRONGER LOW OFF THE MID ATLANTIC COAST ON WEDNESDAY. ONE TO TWO TENTH OF AN INCH OF LIQUID IS EXPECTED...MAINLY IN THE FORM OF RAIN. THE COOLER HIGHER ELEVATIONS OF N CENTRAL UPPER MI THAT SHOULD TOP OUT IN THE MID 30S TUESDAY SHOULD STAY IN THE MOSTLY IN THE FORM OF SNOW. STILL HAVE HALF OF AN INCH TO RIGHT AROUND AN INCH OF NEW SNOW FORECAST THROUGH TUESDAY EVENING...AS THE DGZ AROUND 600MB IS BRIEFLY ACCOMPANIED BY ENOUGH MOISTURE TO PRODUCE ACCUMULATING SNOW. S SFC TO 850MB WINDS OF 15-25KTS OVER N CENTRAL TO NE UPPER MI TUESDAY SHOULD KEEP DOWNSLOPE AREAS A COUPLE DEGREES WARMER. GIVEN THE FAIRLY CONSISTENT MODEL RUNS...A BLEND SEEMS REASONABLE FOR MUCH OF THE PERIOD. DRIER AIR WILL SLOWLY WORK IN WEDNESDAY AND STAY THROUGH AT LEAST THURSDAY NIGHT AS HIGH PRESSURE REMAINS IN CONTROL AT THE SFC AND ALOFT. SW FLOW WILL BE ON THE INCREASE AGAIN FRIDAY AFTERNOON AND EVENING AS THE SFC RIDGE WEAKENS OVER THE CWA AND THE APEX OF THE 500MB RIDGE EDGES JUST TO OUR E. WITH SOME OF THE WARMEST AIR WE HAVE HAD OVER THE CWA IN A COUPLE OF WEEKS /850MB TEMPS POSSIBLY BU TO 12C AT 00Z SUN OFF THE NEW 11/00Z ECMWF/. WITH ALL THE WARM AIR AND INCREASED LAPSE RATES KEPT THE POTENTIAL FOR TS SATURDAY INTO SUNDAY...BUT DID A BIT OF TAILORING TO ALIGN BETTER WITH THE LATEST MODEL DATA. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 1244 AM EST MON NOV 5 2012 SAW/CMX...EXPECT MVFR CONDITIONS TO DOMINATE THRU THIS MRNG WITH SLOWLY VEERING UPSLOPE NE TO E FLOW ON SRN FLANK OF HI PRES SLIDING SLOWLY SEWD THRU NW ONTARIO AND UNDER SHARP LOW SUBSIDENCE INVRN SHOWN ON LOCAL 00Z RAOBS. ALTHOUGH THERE COULD BE A FEW -SHSN MAINLY AT CMX WITH MORE FVRBL UPSLOPE FLOW...LO INVRN BASE WL LIMIT THE INTENSITY OF THIS PCPN AND ANY RESTRICTION TO VSBY. BY MON AFTN... THE COMBINATION OF DIURNAL HEATING AND WSHFT TO THE S SHOULD ALLOW A RETURN OF VFR CONDITIONS THAT WL PERSIST THRU THE REST OF THE TAF PERIOD. KIWD...LOOK FOR MVFR CIGS TO RETURN EARLY THIS MRNG AND PERSIST UNTIL AFTER SUNRISE...WHEN DAYTIME HEATING/WSHFT TO A DOWNSLOPING S DIRECTION WL BRING A RETURN OF VFR CONDITIONS BY MON AFTN THAT PERSISTS THRU THE END OF THE TAF PERIOD. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 525 AM EST MON NOV 5 2012 AS HIGH PRESSURE OVER NORTHWEST ONTARIO SLIDES SOUTHEAST THROUGH THE UPPER GREAT LAKES TODAY...EXPECT WINDS TO BE LIGHT AND LESS THAN 20KTS. A LOW PRESSURE SYSTEM MOVING THROUGH CENTRAL CANADA ON TUESDAY WILL SWEEP A SURFACE TROUGH ACROSS THE UPPER GREAT LAKES REGION AND BRING INCREASING SOUTHWESTERLY WINDS TO 20-30 KTS. A WEAK HIGH PRESSURE RIDGE WILL THEN SLIDE INTO THE UPPER GREAT LAKES WEDNESDAY AFTERNOON AND REMAIN INTO FRIDAY. A 29.5 INCH LOW PRESSURE SYSTEM DEVELOPING IN THE CENTRAL PLAINS ON FRIDAY IS EXPECTED TO LIFT NORTH INTO THE UPPER MISSISSIPPI VALLEY BY SATURDAY NIGHT. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLB LONG TERM...KF AVIATION...KC MARINE...JLB
AREA FORECAST DISCUSSION
NWS HASTINGS NE
645 AM CST MON NOV 5 2012 .UPDATE...JUST SHIPPED A FAIRLY MINOR UPDATE...MAINLY TO ACKNOWLEDGE THE OBVIOUS FROM THE LATEST 11-3.9 MICRON SATELLITE IMAGERY AND BOOST SKY COVER THIS MORNING TO 100 PERCENT FOR ESSENTIALLY THE ENTIRE CWA. AS HAS BEEN FAIRLY WELL CAPTURED BY VARIOUS MODEL LOW-LEVEL RH FIELDS AND ALSO THE LOW CLOUD COVER GUIDANCE FROM THE 09Z HRRR...BLANKET OF LOW STRATUS HAS RAPIDLY OVERTAKEN ALL AREAS OVER THE PAST FEW HOURS. PLENTY OF UNCERTAINTY REMAINS ON ITS ULTIMATE FATE...BUT WILL CONTINUE BANKING ON SOME DEGREE OF AFTERNOON EROSION...LIKELY IN SOME WEST- TO-EAST FASHION. JUST IN CASE THESE LOW CLOUDS HANG FIRMER THAN THOUGHT...WHICH IS VERY POSSIBLE BASED ON WHAT HAPPENED DURING A STRETCH OF DAYS A FEW WEEKS AGO...NUDGED DOWN HIGH TEMPS 1 DEGREE ACROSS THE BOARD. MAYBE THIS WILL ULTIMATELY PROVE TO BE A MINOR BUT INCORRECT MOVE...BUT WHEN IT COMES TO COLD SEASON STRATUS...DOWNWARD IS USUALLY THE DIRECTION TO GO AND THERE IS INCREASING SUPPORT FOR SLIGHTLY COOLER HIGHS IN HOURLY TEMP FIELDS FROM THE 09Z HRRR AS WELL. REITERATING FROM THE EARLIER AFD...WE ARE NOW TRULY AT THE MERCY OF THE LOW STRATUS TODAY AND TO WHAT DEGREE IT DOES/DOESN`T BREAK. && .PREV DISCUSSION... /ISSUED 539 AM CST MON NOV 5 2012/ AVIATION...12Z KGRI TAF. CEILINGS ARE A CHALLENGE THIS MORNING AS SOME LOCATIONS ARE DIPPING JUST INSIDE THE IFR CATEGORY...BUT THE TERMINAL SHOULD BE JUST FAR ENOUGH SOUTHWEST TO HAVE PRIMARILY MVFR CONDITIONS. THE BREEZY NORTH/NORTHWEST WIND SHOULD DECREASE BY AFTERNOON...BUT THE STRATUS WILL BE STUBBORN TO EXIT...BUT SHOULD AT LEAST RAISE A BIT OVER TIME TODAY. TOUGH CALL FOR END OF STRATUS BUT WAS MORE PESSIMISTIC THAN MODEL GUIDANCE FORECASTS...GIVEN THE RECENT MODEL PERFORMANCES. PREV DISCUSSION... /ISSUED 459 AM CST MON NOV 5 2012/ SHORT TERM...THROUGH WEDNESDAY NIGHT. DESPITE THE LACK OF MEASURABLE PRECIPITATION CHANCES DURING THE NEXT 72 HOURS...JUST THE FIRST 12 HOURS ALONE PRESENT ANOTHER TRICKY CLOUD COVER/TEMPERATURE FORECAST. IN GENERAL THOUGH...NO MAJOR CHANGE IN EXPECTATIONS FROM PREVIOUS FORECAST...WITH PROGRESSIVELY WARMER TEMPS IN STORE THROUGH WEDNESDAY...AND TODAY STILL VERY MUCH LOOKING LIKE THE CHILLIEST DAY OF THE WORK-WEEK. 09Z CENTRAL PLAINS OBJECTIVE SURFACE ANALYSIS FEATURES A 1015MB LOW ALONG THE KS/MO BORDER...WHILE AN ELONGATED RIDGE AXIS EXTENDS FROM WY TO ND AHEAD OF THE NEXT UPSTREAM NORTHERN ROCKIES LOW. IN BETWEEN THESE FEATURES...A TIGHTENED PRESSURE GRADIENT BEHIND A COLD FRONT IS PROMOTING A NOTICEABLE NORTH-NORTHWEST BREEZE ACROSS MOST ALL OF THE CWA EARLY THIS MORNING...WITH SUSTAINED SPEEDS RANGING 10-20 MPH WITH HIGHER GUSTS. PRE-DAWN TEMPS ACROSS THE CWA ARE GENERALLY IN THE 37-43 RANGE. ALOFT...WATER VAPOR IMAGERY AND SHORT TERM MODEL DATA CLEARLY DEPICT A WELL-DEFINED MID LEVEL SHORTWAVE TROUGH DROPPING SOUTH ACROSS CENTRAL/EASTERN NEB INTO CENTRAL/EASTERN KS AT THIS HOUR...WITH THIS WAVE STILL PROMOTING STEADIER LIGHT RAIN FROM THE MO RIVER EASTWARD INTO IA/MO ON THE EAST SIDE OF A STOUT 110+KT 300MB JET STREAK NOSING SOUTHWARD ACROSS THE AREA. MEANWHILE...ISOLATED/SCATTERED LIGHT SHOWERS THAT AFFECTED PARTS OF MAINLY THE EASTERN CWA EARLIER TONIGHT HAVE SINCE PUSHED OFF EAST OF THE AREA...LIKELY LEAVING NO MORE THAN A FEW HUNDREDTHS OF AN INCH IN THEIR WAKE. AS THE NIGHT HAS WORN ON...THIS LIGHT RAIN AND ASSOCIATED MID LEVEL CLOUDS HAVE SINCE BEEN REPLACED BY A RATHER SOLID BLANKET OF LOW STRATUS AVERAGING UNDER 2000 FT...WHICH HAS ALREADY OVERTAKEN ROUGHLY THE NORTHEAST 2/3 OF THE CWA...AND IS QUICKLY ADVANCING INTO SOUTHWEST COUNTIES AS WELL. TODAY...CLOUD COVER/TEMPS ARE CLEARLY THE BIGGEST ISSUE. PRECIPITATION-WISE...OPTED TO OMIT ALL MENTION THROUGH THE 6AM-6PM DAYTIME PERIOD...ALTHOUGH SUPPOSE ITS NOT COMPLETELY OUT OF THE QUESTION THAT SOME LIGHT DRIZZLE MIGHT YET MATERIALIZE BETWEEN NOW AND MID-MORNING ESPECIALLY IN NORTHEAST COUNTIES. HOWEVER...NAM SOUNDINGS LEAVE A BIT TO BE DESIRED IN TERMS OF LOW LEVEL SATURATION DEPTH FOR DRIZZLE PRODUCTION...AND THUS DO NOT PLAN ON INSERTING ANY MENTION UNLESS GROUND TRUTH REPORTS PROVE IT NECESSARY. TEMP-WISE...MUCH LIKE SOME FORGETTABLE DAYS A FEW WEEKS AGO...WE ARE TRULY AT THE MERCY OF THE LOW STRATUS DECK...AND HOW QUICKLY IT TRIES TO SCATTER OUT OR ADVECT OUT OF THE AREA. AT LEAST FOR THE MORNING HOURS...HAVE FAIRLY HIGH CONFIDENCE THAT MOST IF NOT ALL OF THE CWA IS GOING TO BE QUITE SOCKED IN OVERCAST...AND ALTHOUGH RAISED SKY COVER QUITE A BIT DID PROBABLY NOT GO HIGH ENOUGH IN SOUTHWEST AREAS. BASED ON LOW LEVEL RH PROGS FROM MODELS SUCH AS THE 06Z NAM AND 05Z HRRR WE SHOULD...AT LEAST IN THEORY...SEE SOME KIND OF WEST-TO-EAST PARTIAL CLEARING TREND AS THE AFTERNOON WEARS ON...ALTHOUGH EVEN AREAS THAT LOSE THE LOW CLOUDS SHOULD STILL FARE NO BETTER THAN PARTLY CLOUDY SKIES DUE TO INCOMING HIGH CIRRUS FROM THE NORTHWEST. EASTERN COUNTIES...ESPECIALLY ALONG HWY 81...SHOULD BE LAST TO SEE THE BREAKUP OF THE LOW STRATUS...AND MAY STRUGGLE TO SEE MUCH SUN AT ALL TODAY. ALL THIS BEING SAID...THERE IS CERTAINLY POTENTIAL FOR MISSING HIGHS BY 5+ DEGREES IF CLOUD EXPECTATION DON/T PAN OUT...BUT FOR NOW MADE ONLY MINOR TWEAKS TO PREVIOUS FORECAST...AIMING FOR A RANGE FROM UPPER 40S EAST TO MID 50S SOUTHWEST. ALTHOUGH THIS MORNING WILL REMAIN LEGITIMATELY BREEZY IN THE WAKE OF THE COLD FRONT...ARGUABLY THE BIGGEST CHANGE MADE TO PREVIOUS FORECAST WAS TO DECREASE AFTERNOON WIND SPEEDS AT LEAST 5-7 MPH...WITH SUSTAINED NORTHERLY SPEEDS DECREASING TO AROUND 10 MPH OR LESS BY THE MID-LATE AFTERNOON HOURS. FOR THE 6PM-6AM TONIGHT PERIOD...CONTINUED TO LEAVE ALL PRECIP MENTION OUT...BUT ESPECIALLY NORTHEASTERN COUNTIES COULD END UP IN RELATIVELY CLOSE PROXIMITY TO ANOTHER ROUND OF SPRINKLES/LIGHT RAIN...AND THIS IS SOMETHING THAT BEARS WATCHING BY THE NEXT FEW SHIFTS. IN SHORT...THE NEXT IN A SERIES OF NORTHWEST FLOW SHORTWAVES AND AN ASSOCIATED UPPER LEVEL JET STREAK WILL RIDE DOWN ACROSS THE DAKOTAS INTO IA/NORTHEAST NEB AS THE NIGHT WEARS ON...PROMOTING LEGITIMATE LIGHT RAIN CHANCES ALONG ITS TRACK. AT THIS TIME...IT APPEARS THE CWA WILL RESIDE TOO FAR SOUTHWEST TO REALIZE ANY OF THIS PRECIPITATION GIVEN THE PRESENCE OF PLENTY OF DRY AIR BELOW 700MB PER NAM SOUNDINGS...BUT AGAIN WOULD NOT BE SHOCKED TO SEE A FEW SPRINKLES TRY TO SKIRT NORTHERN AREAS. AT THE SURFACE...THIS MID LEVEL WAVE WILL DRIVE ANOTHER WEAK COLD FRONT INTO THE CWA MAINLY AFTER MIDNIGHT...SWITCHING BREEZES FROM SOUTHERLY TO WEST-NORTHWEST IN ITS WAKE. ALTHOUGH NOT OFFICIALLY REFLECTED IN CURRENT GRIDS...WE COULD SEE STEADY OR EVEN RISING TEMPS LATE TONIGHT BEHIND THIS FRONT AS MIXING PICKS UP...BUT FOR NOW HAVE RETAINED A TRADITIONAL DIURNAL CURVE BUT DID RAISE LOWS A FEW DEGREES MOST AREAS...WITH MOST ALL AREAS BOTTOMING OUT SOMEWHERE IN THE 34-38 RANGE. FOR TUESDAY...ALTHOUGH THERE WILL UNDOUBTEDLY BE SOME DEGREE OF PASSING MID-HIGH CLOUDS...THERE SHOULD NOT BE THE LOW STRATUS ISSUES WE ARE STARTING OUT WITH TODAY...AND OVERALL THINK IT SHOULD BE A MOSTLY SUNNY/PARTLY CLOUD DAY. ANOTHER FAIRLY BREEZY DAY IS IN STORE IN THE WAKE OF THE MID LEVEL WAVE HEADING SOUTHEAST ACROSS IA/MO...WITH SUSTAINED NORTH-NORTHWEST BREEZES AGAIN 15-20 MPH WITH HIGHER GUSTS. DESPITE THESE NORTH WINDS...DECENT MIXING AND SUNSHINE SHOULD GIVE TEMPS A NOTICEABLE BOOST OVER THOSE OF TODAY...AND RAISED HIGHS 1-2 DEGREES MOST AREAS PER MULTI-MODEL CONSENSUS...RANGING FROM UPPER 50S NORTHEAST...LOW 60S TRI-CITIES AND UPPER 60S SOUTHWEST. RELATIVE HUMIDITY VALUES ARE NOW FORECAST INTO THE UPPER 20S DURING THE AFTERNOON MAINLY NORTH OF I-80...BUT SHOULD HOLD SAFELY ABOVE CRITICAL FIRE WEATHER TERRITORY. TUESDAY NIGHT...KEPT POPS ZEROED OUT...AS BROAD RIDGING ALOFT BUILDS A BIT MORE SO OVER THE CENTRAL PLAINS...WHILE AT THE SURFACE...A RIDGE AXIS PASSES THROUGH THE CWA DURING THE NIGHT PROMOTING GENERALLY LIGHT/VARIABLE BREEZES. ASSUMING CLOUDS ARE FAIRLY MINIMAL AS EXPECTED...THIS SHOULD ALLOW TEMPS TO DROP OFF RATHER EFFICIENTLY AND BASED ON MET/MAV GUIDANCE BLEND LOWERED LOWS 1-5 DEGREES ACROSS THE AREA...NOW AIMING FOR MID-UPPER 20S NORTHEAST TO LOW 30S SOUTHWEST. WEDNESDAY...WE CONTINUE TO SEE ESSENTIALLY ZERO RISK OF PRECIP...AS THE HEART OF THE MID-UPPER RIDGE AXIS SLIDES OVER THE CENTRAL PLAINS...BETWEEN A DEEP EASTERN CONUS TROUGH AND THE NEXT UPSTREAM SHORTWAVE OFF THE PACIFIC NORTHWEST COAST. AT THE SURFACE...SOUTHERLY BREEZES WILL PICK UP A BIT BEHIND THE DEPARTING RIDGE AXIS AND IN RESPONSE TO A MODEST HIGH PLAINS LEE TROUGH...AND NUDGED UP SUSTAINED SPEEDS TO AT LEAST 15 MPH DURING THE AFTERNOON. THESE SOUTH BREEZES SHOULD GIVE TEMPS ANOTHER UPWARD BOOST VERSUS THE PREVIOUS DAY. ALTHOUGH PLAYED IT SOMEWHAT CONSERVATIVE AND STAYED AT LEAST 2-4 DEGREES COOLER THAN THE RAW NAM SOLUTION...DID INCREASE PREVIOUS HIGHS GENERALLY 2 DEGREES NOW AIMING FOR A RANGE FROM LOW 60S EAST TO UPPER 60S/LOW 70S WEST. WEDNESDAY NIGHT...FLOW TRANSITIONS TO QUASI-ZONAL OR EVEN SLIGHTLY SOUTHWESTERLY AS THE CENTER OF THE MID-UPPER RIDGE AXIS SLIDES EAST. WITH THE EXPECTATION OF A LEAST LIGHT BUT STEADY SOUTHERLY BREEZES IN MOST AREAS...AM CALLING FOR A BIT WARMER NIGHT THAN TUESDAY NIGHT...AND KEPT LOWS CLOSE TO PREVIOUS FORECAST WITH MOST AREAS HOLDING UP IN THE 37-41 RANGE. LONG TERM...THURSDAY THROUGH SUNDAY. MAIN CHALLENGES INCLUDE PRECIPITATION CHANCES AND TYPE ALONG WITH TEMPERATURES. UPPER PATTERN WILL BE IN THE PROCESS OF AMPLIFICATION FOR THE LONG TERM AS A MAJOR PATTERN SHIFT OCCURS. MODELS ARE IN GOOD AGREEMENT WITH THIS PATTERN SHIFT...BUT DO HAVE SOME MINOR DIFFERENCES. WE BEGIN THURSDAY WITH A DEEPENING EASTERN PACIFIC TROUGH AND PLAINS RIDGE. THIS PLACES US IN A VERY MILD REGIME TO BEGIN THE LONG TERM. THESE FEATURES WILL TRANSLATE EAST OVER TIME AND BY SATURDAY...THE ROBUST DIGGING LONGWAVE TROUGH WILL BE PROMINENT OVER THE INTERMOUNTAIN WEST. SATURDAY COULD TURN OUT TO BE QUITE WARM AHEAD OF THE ASSOCIATED COLD FRONT FROM THE TROUGH THAT IS EXPECTED TO ARRIVE BY SATURDAY NIGHT. THEREFORE I INCREASED HIGH TEMPERATURES ON SATURDAY COMPARED TO ALLBLEND INITIALIZATION. THERE COULD BE SOME SHOWER AND EVEN THUNDERSTORM ACTIVITY IN THE SOUTHEASTERN CWA WHERE MUCAPES WOULD SUPPORT THIS...BUT IT APPEARS FOR NOW THAT MOST OF ANY PRECIPITATION SHOULD FALL SATURDAY NIGHT ALONG AND BEHIND THE COLD FRONT. BY THE TIME WE GET COLD ENOUGH FOR SNOW...QPF SHOULD BE LIMITED...SO NOT LOOKING FOR MUCH ACCUMULATION. THE GFS SWINGS A CLOSED LOW AT 700 MB OVER THE CWA FOR SATURDAY NIGHT WHICH COULD MEAN MORE SNOW...BUT I AM NOT BUYING IN TO THIS AT THIS TIME. I INCREASED WIND SPEEDS SIGNIFICANTLY ON SATURDAY NIGHT AND SUNDAY AS STRONG COLD AIR ADVECTION IS ANTICIPATED FOR SATURDAY NIGHT AND SUNDAY BEHIND THE LONGWAVE TROUGH MOVING EAST. THE TEMPERATURE DROP WILL LIKELY BE TREMENDOUS BETWEEN SATURDAY AND SUNDAY AND I HAVE LOWERED TEMPERATURES FROM ALLBLEND INITIALIZATION FOR SUNDAY. IF CLOUDS STICK AROUND FOR A SIGNIFICANT PORTION OF THE DAY ON SUNDAY...WE VERY WELL MAY STRUGGLE TO GET OUT OF THE 20S...AND COUPLED WITH A STRONG NORTHWEST WIND...THIS COULD BE QUITE AN UNCOMFORTABLY COLD DAY...EVEN FOR NOVEMBER STANDARDS. && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$ SHORT TERM/UPDATE...PFANNKUCH LONG TERM/AVIATION...HEINLEIN
AREA FORECAST DISCUSSION
NWS HASTINGS NE
539 AM CST MON NOV 5 2012 .AVIATION...12Z KGRI TAF. CEILINGS ARE A CHALLENGE THIS MORNING AS SOME LOCATIONS ARE DIPPING JUST INSIDE THE IFR CATEGORY...BUT THE TERMINAL SHOULD BE JUST FAR ENOUGH SOUTHWEST TO HAVE PRIMARILY MVFR CONDITIONS. THE BREEZY NORTH/NORTHWEST WIND SHOULD DECREASE BY AFTERNOON...BUT THE STRATUS WILL BE STUBBORN TO EXIT...BUT SHOULD AT LEAST RAISE A BIT OVER TIME TODAY. TOUGH CALL FOR END OF STRATUS BUT WAS MORE PESSIMISTIC THAN MODEL GUIDANCE FORECASTS...GIVEN THE RECENT MODEL PERFORMANCES. && .PREV DISCUSSION... /ISSUED 459 AM CST MON NOV 5 2012/ SHORT TERM...THROUGH WEDNESDAY NIGHT. DESPITE THE LACK OF MEASURABLE PRECIPITATION CHANCES DURING THE NEXT 72 HOURS...JUST THE FIRST 12 HOURS ALONE PRESENT ANOTHER TRICKY CLOUD COVER/TEMPERATURE FORECAST. IN GENERAL THOUGH...NO MAJOR CHANGE IN EXPECTATIONS FROM PREVIOUS FORECAST...WITH PROGRESSIVELY WARMER TEMPS IN STORE THROUGH WEDNESDAY...AND TODAY STILL VERY MUCH LOOKING LIKE THE CHILLIEST DAY OF THE WORK-WEEK. 09Z CENTRAL PLAINS OBJECTIVE SURFACE ANALYSIS FEATURES A 1015MB LOW ALONG THE KS/MO BORDER...WHILE AN ELONGATED RIDGE AXIS EXTENDS FROM WY TO ND AHEAD OF THE NEXT UPSTREAM NORTHERN ROCKIES LOW. IN BETWEEN THESE FEATURES...A TIGHTENED PRESSURE GRADIENT BEHIND A COLD FRONT IS PROMOTING A NOTICEABLE NORTH-NORTHWEST BREEZE ACROSS MOST ALL OF THE CWA EARLY THIS MORNING...WITH SUSTAINED SPEEDS RANGING 10-20 MPH WITH HIGHER GUSTS. PRE-DAWN TEMPS ACROSS THE CWA ARE GENERALLY IN THE 37-43 RANGE. ALOFT...WATER VAPOR IMAGERY AND SHORT TERM MODEL DATA CLEARLY DEPICT A WELL-DEFINED MID LEVEL SHORTWAVE TROUGH DROPPING SOUTH ACROSS CENTRAL/EASTERN NEB INTO CENTRAL/EASTERN KS AT THIS HOUR...WITH THIS WAVE STILL PROMOTING STEADIER LIGHT RAIN FROM THE MO RIVER EASTWARD INTO IA/MO ON THE EAST SIDE OF A STOUT 110+KT 300MB JET STREAK NOSING SOUTHWARD ACROSS THE AREA. MEANWHILE...ISOLATED/SCATTERED LIGHT SHOWERS THAT AFFECTED PARTS OF MAINLY THE EASTERN CWA EARLIER TONIGHT HAVE SINCE PUSHED OFF EAST OF THE AREA...LIKELY LEAVING NO MORE THAN A FEW HUNDREDTHS OF AN INCH IN THEIR WAKE. AS THE NIGHT HAS WORN ON...THIS LIGHT RAIN AND ASSOCIATED MID LEVEL CLOUDS HAVE SINCE BEEN REPLACED BY A RATHER SOLID BLANKET OF LOW STRATUS AVERAGING UNDER 2000 FT...WHICH HAS ALREADY OVERTAKEN ROUGHLY THE NORTHEAST 2/3 OF THE CWA...AND IS QUICKLY ADVANCING INTO SOUTHWEST COUNTIES AS WELL. TODAY...CLOUD COVER/TEMPS ARE CLEARLY THE BIGGEST ISSUE. PRECIPITATION-WISE...OPTED TO OMIT ALL MENTION THROUGH THE 6AM-6PM DAYTIME PERIOD...ALTHOUGH SUPPOSE ITS NOT COMPLETELY OUT OF THE QUESTION THAT SOME LIGHT DRIZZLE MIGHT YET MATERIALIZE BETWEEN NOW AND MID-MORNING ESPECIALLY IN NORTHEAST COUNTIES. HOWEVER...NAM SOUNDINGS LEAVE A BIT TO BE DESIRED IN TERMS OF LOW LEVEL SATURATION DEPTH FOR DRIZZLE PRODUCTION...AND THUS DO NOT PLAN ON INSERTING ANY MENTION UNLESS GROUND TRUTH REPORTS PROVE IT NECESSARY. TEMP-WISE...MUCH LIKE SOME FORGETTABLE DAYS A FEW WEEKS AGO...WE ARE TRULY AT THE MERCY OF THE LOW STRATUS DECK...AND HOW QUICKLY IT TRIES TO SCATTER OUT OR ADVECT OUT OF THE AREA. AT LEAST FOR THE MORNING HOURS...HAVE FAIRLY HIGH CONFIDENCE THAT MOST IF NOT ALL OF THE CWA IS GOING TO BE QUITE SOCKED IN OVERCAST...AND ALTHOUGH RAISED SKY COVER QUITE A BIT DID PROBABLY NOT GO HIGH ENOUGH IN SOUTHWEST AREAS. BASED ON LOW LEVEL RH PROGS FROM MODELS SUCH AS THE 06Z NAM AND 05Z HRRR WE SHOULD...AT LEAST IN THEORY...SEE SOME KIND OF WEST-TO-EAST PARTIAL CLEARING TREND AS THE AFTERNOON WEARS ON...ALTHOUGH EVEN AREAS THAT LOSE THE LOW CLOUDS SHOULD STILL FARE NO BETTER THAN PARTLY CLOUDY SKIES DUE TO INCOMING HIGH CIRRUS FROM THE NORTHWEST. EASTERN COUNTIES...ESPECIALLY ALONG HWY 81...SHOULD BE LAST TO SEE THE BREAKUP OF THE LOW STRATUS...AND MAY STRUGGLE TO SEE MUCH SUN AT ALL TODAY. ALL THIS BEING SAID...THERE IS CERTAINLY POTENTIAL FOR MISSING HIGHS BY 5+ DEGREES IF CLOUD EXPECTATION DON/T PAN OUT...BUT FOR NOW MADE ONLY MINOR TWEAKS TO PREVIOUS FORECAST...AIMING FOR A RANGE FROM UPPER 40S EAST TO MID 50S SOUTHWEST. ALTHOUGH THIS MORNING WILL REMAIN LEGITIMATELY BREEZY IN THE WAKE OF THE COLD FRONT...ARGUABLY THE BIGGEST CHANGE MADE TO PREVIOUS FORECAST WAS TO DECREASE AFTERNOON WIND SPEEDS AT LEAST 5-7 MPH...WITH SUSTAINED NORTHERLY SPEEDS DECREASING TO AROUND 10 MPH OR LESS BY THE MID-LATE AFTERNOON HOURS. FOR THE 6PM-6AM TONIGHT PERIOD...CONTINUED TO LEAVE ALL PRECIP MENTION OUT...BUT ESPECIALLY NORTHEASTERN COUNTIES COULD END UP IN RELATIVELY CLOSE PROXIMITY TO ANOTHER ROUND OF SPRINKLES/LIGHT RAIN...AND THIS IS SOMETHING THAT BEARS WATCHING BY THE NEXT FEW SHIFTS. IN SHORT...THE NEXT IN A SERIES OF NORTHWEST FLOW SHORTWAVES AND AN ASSOCIATED UPPER LEVEL JET STREAK WILL RIDE DOWN ACROSS THE DAKOTAS INTO IA/NORTHEAST NEB AS THE NIGHT WEARS ON...PROMOTING LEGITIMATE LIGHT RAIN CHANCES ALONG ITS TRACK. AT THIS TIME...IT APPEARS THE CWA WILL RESIDE TOO FAR SOUTHWEST TO REALIZE ANY OF THIS PRECIPITATION GIVEN THE PRESENCE OF PLENTY OF DRY AIR BELOW 700MB PER NAM SOUNDINGS...BUT AGAIN WOULD NOT BE SHOCKED TO SEE A FEW SPRINKLES TRY TO SKIRT NORTHERN AREAS. AT THE SURFACE...THIS MID LEVEL WAVE WILL DRIVE ANOTHER WEAK COLD FRONT INTO THE CWA MAINLY AFTER MIDNIGHT...SWITCHING BREEZES FROM SOUTHERLY TO WEST-NORTHWEST IN ITS WAKE. ALTHOUGH NOT OFFICIALLY REFLECTED IN CURRENT GRIDS...WE COULD SEE STEADY OR EVEN RISING TEMPS LATE TONIGHT BEHIND THIS FRONT AS MIXING PICKS UP...BUT FOR NOW HAVE RETAINED A TRADITIONAL DIURNAL CURVE BUT DID RAISE LOWS A FEW DEGREES MOST AREAS...WITH MOST ALL AREAS BOTTOMING OUT SOMEWHERE IN THE 34-38 RANGE. FOR TUESDAY...ALTHOUGH THERE WILL UNDOUBTEDLY BE SOME DEGREE OF PASSING MID-HIGH CLOUDS...THERE SHOULD NOT BE THE LOW STRATUS ISSUES WE ARE STARTING OUT WITH TODAY...AND OVERALL THINK IT SHOULD BE A MOSTLY SUNNY/PARTLY CLOUD DAY. ANOTHER FAIRLY BREEZY DAY IS IN STORE IN THE WAKE OF THE MID LEVEL WAVE HEADING SOUTHEAST ACROSS IA/MO...WITH SUSTAINED NORTH-NORTHWEST BREEZES AGAIN 15-20 MPH WITH HIGHER GUSTS. DESPITE THESE NORTH WINDS...DECENT MIXING AND SUNSHINE SHOULD GIVE TEMPS A NOTICEABLE BOOST OVER THOSE OF TODAY...AND RAISED HIGHS 1-2 DEGREES MOST AREAS PER MULTI-MODEL CONSENSUS...RANGING FROM UPPER 50S NORTHEAST...LOW 60S TRI-CITIES AND UPPER 60S SOUTHWEST. RELATIVE HUMIDITY VALUES ARE NOW FORECAST INTO THE UPPER 20S DURING THE AFTERNOON MAINLY NORTH OF I-80...BUT SHOULD HOLD SAFELY ABOVE CRITICAL FIRE WEATHER TERRITORY. TUESDAY NIGHT...KEPT POPS ZEROED OUT...AS BROAD RIDGING ALOFT BUILDS A BIT MORE SO OVER THE CENTRAL PLAINS...WHILE AT THE SURFACE...A RIDGE AXIS PASSES THROUGH THE CWA DURING THE NIGHT PROMOTING GENERALLY LIGHT/VARIABLE BREEZES. ASSUMING CLOUDS ARE FAIRLY MINIMAL AS EXPECTED...THIS SHOULD ALLOW TEMPS TO DROP OFF RATHER EFFICIENTLY AND BASED ON MET/MAV GUIDANCE BLEND LOWERED LOWS 1-5 DEGREES ACROSS THE AREA...NOW AIMING FOR MID-UPPER 20S NORTHEAST TO LOW 30S SOUTHWEST. WEDNESDAY...WE CONTINUE TO SEE ESSENTIALLY ZERO RISK OF PRECIP...AS THE HEART OF THE MID-UPPER RIDGE AXIS SLIDES OVER THE CENTRAL PLAINS...BETWEEN A DEEP EASTERN CONUS TROUGH AND THE NEXT UPSTREAM SHORTWAVE OFF THE PACIFIC NORTHWEST COAST. AT THE SURFACE...SOUTHERLY BREEZES WILL PICK UP A BIT BEHIND THE DEPARTING RIDGE AXIS AND IN RESPONSE TO A MODEST HIGH PLAINS LEE TROUGH...AND NUDGED UP SUSTAINED SPEEDS TO AT LEAST 15 MPH DURING THE AFTERNOON. THESE SOUTH BREEZES SHOULD GIVE TEMPS ANOTHER UPWARD BOOST VERSUS THE PREVIOUS DAY. ALTHOUGH PLAYED IT SOMEWHAT CONSERVATIVE AND STAYED AT LEAST 2-4 DEGREES COOLER THAN THE RAW NAM SOLUTION...DID INCREASE PREVIOUS HIGHS GENERALLY 2 DEGREES NOW AIMING FOR A RANGE FROM LOW 60S EAST TO UPPER 60S/LOW 70S WEST. WEDNESDAY NIGHT...FLOW TRANSITIONS TO QUASI-ZONAL OR EVEN SLIGHTLY SOUTHWESTERLY AS THE CENTER OF THE MID-UPPER RIDGE AXIS SLIDES EAST. WITH THE EXPECTATION OF A LEAST LIGHT BUT STEADY SOUTHERLY BREEZES IN MOST AREAS...AM CALLING FOR A BIT WARMER NIGHT THAN TUESDAY NIGHT...AND KEPT LOWS CLOSE TO PREVIOUS FORECAST WITH MOST AREAS HOLDING UP IN THE 37-41 RANGE. LONG TERM...THURSDAY THROUGH SUNDAY. MAIN CHALLENGES INCLUDE PRECIPITATION CHANCES AND TYPE ALONG WITH TEMPERATURES. UPPER PATTERN WILL BE IN THE PROCESS OF AMPLIFICATION FOR THE LONG TERM AS A MAJOR PATTERN SHIFT OCCURS. MODELS ARE IN GOOD AGREEMENT WITH THIS PATTERN SHIFT...BUT DO HAVE SOME MINOR DIFFERENCES. WE BEGIN THURSDAY WITH A DEEPENING EASTERN PACIFIC TROUGH AND PLAINS RIDGE. THIS PLACES US IN A VERY MILD REGIME TO BEGIN THE LONG TERM. THESE FEATURES WILL TRANSLATE EAST OVER TIME AND BY SATURDAY...THE ROBUST DIGGING LONGWAVE TROUGH WILL BE PROMINENT OVER THE INTERMOUNTAIN WEST. SATURDAY COULD TURN OUT TO BE QUITE WARM AHEAD OF THE ASSOCIATED COLD FRONT FROM THE TROUGH THAT IS EXPECTED TO ARRIVE BY SATURDAY NIGHT. THEREFORE I INCREASED HIGH TEMPERATURES ON SATURDAY COMPARED TO ALLBLEND INITIALIZATION. THERE COULD BE SOME SHOWER AND EVEN THUNDERSTORM ACTIVITY IN THE SOUTHEASTERN CWA WHERE MUCAPES WOULD SUPPORT THIS...BUT IT APPEARS FOR NOW THAT MOST OF ANY PRECIPITATION SHOULD FALL SATURDAY NIGHT ALONG AND BEHIND THE COLD FRONT. BY THE TIME WE GET COLD ENOUGH FOR SNOW...QPF SHOULD BE LIMITED...SO NOT LOOKING FOR MUCH ACCUMULATION. THE GFS SWINGS A CLOSED LOW AT 700 MB OVER THE CWA FOR SATURDAY NIGHT WHICH COULD MEAN MORE SNOW...BUT I AM NOT BUYING IN TO THIS AT THIS TIME. I INCREASED WIND SPEEDS SIGNIFICANTLY ON SATURDAY NIGHT AND SUNDAY AS STRONG COLD AIR ADVECTION IS ANTICIPATED FOR SATURDAY NIGHT AND SUNDAY BEHIND THE LONGWAVE TROUGH MOVING EAST. THE TEMPERATURE DROP WILL LIKELY BE TREMENDOUS BETWEEN SATURDAY AND SUNDAY AND I HAVE LOWERED TEMPERATURES FROM ALLBLEND INITIALIZATION FOR SUNDAY. IF CLOUDS STICK AROUND FOR A SIGNIFICANT PORTION OF THE DAY ON SUNDAY...WE VERY WELL MAY STRUGGLE TO GET OUT OF THE 20S...AND COUPLED WITH A STRONG NORTHWEST WIND...THIS COULD BE QUITE AN UNCOMFORTABLY COLD DAY...EVEN FOR NOVEMBER STANDARDS. && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$ SHORT TERM...PFANNKUCH LONG TERM/AVIATION...HEINLEIN
AREA FORECAST DISCUSSION
NWS HASTINGS NE
459 AM CST MON NOV 5 2012 .SHORT TERM...THROUGH WEDNESDAY NIGHT. DESPITE THE LACK OF MEASURABLE PRECIPITATION CHANCES DURING THE NEXT 72 HOURS...JUST THE FIRST 12 HOURS ALONE PRESENT ANOTHER TRICKY CLOUD COVER/TEMPERATURE FORECAST. IN GENERAL THOUGH...NO MAJOR CHANGE IN EXPECTATIONS FROM PREVIOUS FORECAST...WITH PROGRESSIVELY WARMER TEMPS IN STORE THROUGH WEDNESDAY...AND TODAY STILL VERY MUCH LOOKING LIKE THE CHILLIEST DAY OF THE WORK-WEEK. 09Z CENTRAL PLAINS OBJECTIVE SURFACE ANALYSIS FEATURES A 1015MB LOW ALONG THE KS/MO BORDER...WHILE AN ELONGATED RIDGE AXIS EXTENDS FROM WY TO ND AHEAD OF THE NEXT UPSTREAM NORTHERN ROCKIES LOW. IN BETWEEN THESE FEATURES...A TIGHTENED PRESSURE GRADIENT BEHIND A COLD FRONT IS PROMOTING A NOTICEABLE NORTH-NORTHWEST BREEZE ACROSS MOST ALL OF THE CWA EARLY THIS MORNING...WITH SUSTAINED SPEEDS RANGING 10-20 MPH WITH HIGHER GUSTS. PRE-DAWN TEMPS ACROSS THE CWA ARE GENERALLY IN THE 37-43 RANGE. ALOFT...WATER VAPOR IMAGERY AND SHORT TERM MODEL DATA CLEARLY DEPICT A WELL-DEFINED MID LEVEL SHORTWAVE TROUGH DROPPING SOUTH ACROSS CENTRAL/EASTERN NEB INTO CENTRAL/EASTERN KS AT THIS HOUR...WITH THIS WAVE STILL PROMOTING STEADIER LIGHT RAIN FROM THE MO RIVER EASTWARD INTO IA/MO ON THE EAST SIDE OF A STOUT 110+KT 300MB JET STREAK NOSING SOUTHWARD ACROSS THE AREA. MEANWHILE...ISOLATED/SCATTERED LIGHT SHOWERS THAT AFFECTED PARTS OF MAINLY THE EASTERN CWA EARLIER TONIGHT HAVE SINCE PUSHED OFF EAST OF THE AREA...LIKELY LEAVING NO MORE THAN A FEW HUNDREDTHS OF AN INCH IN THEIR WAKE. AS THE NIGHT HAS WORN ON...THIS LIGHT RAIN AND ASSOCIATED MID LEVEL CLOUDS HAVE SINCE BEEN REPLACED BY A RATHER SOLID BLANKET OF LOW STRATUS AVERAGING UNDER 2000 FT...WHICH HAS ALREADY OVERTAKEN ROUGHLY THE NORTHEAST 2/3 OF THE CWA...AND IS QUICKLY ADVANCING INTO SOUTHWEST COUNTIES AS WELL. TODAY...CLOUD COVER/TEMPS ARE CLEARLY THE BIGGEST ISSUE. PRECIPITATION-WISE...OPTED TO OMIT ALL MENTION THROUGH THE 6AM-6PM DAYTIME PERIOD...ALTHOUGH SUPPOSE ITS NOT COMPLETELY OUT OF THE QUESTION THAT SOME LIGHT DRIZZLE MIGHT YET MATERIALIZE BETWEEN NOW AND MID-MORNING ESPECIALLY IN NORTHEAST COUNTIES. HOWEVER...NAM SOUNDINGS LEAVE A BIT TO BE DESIRED IN TERMS OF LOW LEVEL SATURATION DEPTH FOR DRIZZLE PRODUCTION...AND THUS DO NOT PLAN ON INSERTING ANY MENTION UNLESS GROUND TRUTH REPORTS PROVE IT NECESSARY. TEMP-WISE...MUCH LIKE SOME FORGETTABLE DAYS A FEW WEEKS AGO...WE ARE TRULY AT THE MERCY OF THE LOW STRATUS DECK...AND HOW QUICKLY IT TRIES TO SCATTER OUT OR ADVECT OUT OF THE AREA. AT LEAST FOR THE MORNING HOURS...HAVE FAIRLY HIGH CONFIDENCE THAT MOST IF NOT ALL OF THE CWA IS GOING TO BE QUITE SOCKED IN OVERCAST...AND ALTHOUGH RAISED SKY COVER QUITE A BIT DID PROBABLY NOT GO HIGH ENOUGH IN SOUTHWEST AREAS. BASED ON LOW LEVEL RH PROGS FROM MODELS SUCH AS THE 06Z NAM AND 05Z HRRR WE SHOULD...AT LEAST IN THEORY...SEE SOME KIND OF WEST-TO-EAST PARTIAL CLEARING TREND AS THE AFTERNOON WEARS ON...ALTHOUGH EVEN AREAS THAT LOSE THE LOW CLOUDS SHOULD STILL FARE NO BETTER THAN PARTLY CLOUDY SKIES DUE TO INCOMING HIGH CIRRUS FROM THE NORTHWEST. EASTERN COUNTIES...ESPECIALLY ALONG HWY 81...SHOULD BE LAST TO SEE THE BREAKUP OF THE LOW STRATUS...AND MAY STRUGGLE TO SEE MUCH SUN AT ALL TODAY. ALL THIS BEING SAID...THERE IS CERTAINLY POTENTIAL FOR MISSING HIGHS BY 5+ DEGREES IF CLOUD EXPECTATION DON/T PAN OUT...BUT FOR NOW MADE ONLY MINOR TWEAKS TO PREVIOUS FORECAST...AIMING FOR A RANGE FROM UPPER 40S EAST TO MID 50S SOUTHWEST. ALTHOUGH THIS MORNING WILL REMAIN LEGITIMATELY BREEZY IN THE WAKE OF THE COLD FRONT...ARGUABLY THE BIGGEST CHANGE MADE TO PREVIOUS FORECAST WAS TO DECREASE AFTERNOON WIND SPEEDS AT LEAST 5-7 MPH...WITH SUSTAINED NORTHERLY SPEEDS DECREASING TO AROUND 10 MPH OR LESS BY THE MID-LATE AFTERNOON HOURS. FOR THE 6PM-6AM TONIGHT PERIOD...CONTINUED TO LEAVE ALL PRECIP MENTION OUT...BUT ESPECIALLY NORTHEASTERN COUNTIES COULD END UP IN RELATIVELY CLOSE PROXIMITY TO ANOTHER ROUND OF SPRINKLES/LIGHT RAIN...AND THIS IS SOMETHING THAT BEARS WATCHING BY THE NEXT FEW SHIFTS. IN SHORT...THE NEXT IN A SERIES OF NORTHWEST FLOW SHORTWAVES AND AN ASSOCIATED UPPER LEVEL JET STREAK WILL RIDE DOWN ACROSS THE DAKOTAS INTO IA/NORTHEAST NEB AS THE NIGHT WEARS ON...PROMOTING LEGITIMATE LIGHT RAIN CHANCES ALONG ITS TRACK. AT THIS TIME...IT APPEARS THE CWA WILL RESIDE TOO FAR SOUTHWEST TO REALIZE ANY OF THIS PRECIPITATION GIVEN THE PRESENCE OF PLENTY OF DRY AIR BELOW 700MB PER NAM SOUNDINGS...BUT AGAIN WOULD NOT BE SHOCKED TO SEE A FEW SPRINKLES TRY TO SKIRT NORTHERN AREAS. AT THE SURFACE...THIS MID LEVEL WAVE WILL DRIVE ANOTHER WEAK COLD FRONT INTO THE CWA MAINLY AFTER MIDNIGHT...SWITCHING BREEZES FROM SOUTHERLY TO WEST-NORTHWEST IN ITS WAKE. ALTHOUGH NOT OFFICIALLY REFLECTED IN CURRENT GRIDS...WE COULD SEE STEADY OR EVEN RISING TEMPS LATE TONIGHT BEHIND THIS FRONT AS MIXING PICKS UP...BUT FOR NOW HAVE RETAINED A TRADITIONAL DIURNAL CURVE BUT DID RAISE LOWS A FEW DEGREES MOST AREAS...WITH MOST ALL AREAS BOTTOMING OUT SOMEWHERE IN THE 34-38 RANGE. FOR TUESDAY...ALTHOUGH THERE WILL UNDOUBTEDLY BE SOME DEGREE OF PASSING MID-HIGH CLOUDS...THERE SHOULD NOT BE THE LOW STRATUS ISSUES WE ARE STARTING OUT WITH TODAY...AND OVERALL THINK IT SHOULD BE A MOSTLY SUNNY/PARTLY CLOUD DAY. ANOTHER FAIRLY BREEZY DAY IS IN STORE IN THE WAKE OF THE MID LEVEL WAVE HEADING SOUTHEAST ACROSS IA/MO...WITH SUSTAINED NORTH-NORTHWEST BREEZES AGAIN 15-20 MPH WITH HIGHER GUSTS. DESPITE THESE NORTH WINDS...DECENT MIXING AND SUNSHINE SHOULD GIVE TEMPS A NOTICEABLE BOOST OVER THOSE OF TODAY...AND RAISED HIGHS 1-2 DEGREES MOST AREAS PER MULTI-MODEL CONSENSUS...RANGING FROM UPPER 50S NORTHEAST...LOW 60S TRI-CITIES AND UPPER 60S SOUTHWEST. RELATIVE HUMIDITY VALUES ARE NOW FORECAST INTO THE UPPER 20S DURING THE AFTERNOON MAINLY NORTH OF I-80...BUT SHOULD HOLD SAFELY ABOVE CRITICAL FIRE WEATHER TERRITORY. TUESDAY NIGHT...KEPT POPS ZEROED OUT...AS BROAD RIDGING ALOFT BUILDS A BIT MORE SO OVER THE CENTRAL PLAINS...WHILE AT THE SURFACE...A RIDGE AXIS PASSES THROUGH THE CWA DURING THE NIGHT PROMOTING GENERALLY LIGHT/VARIABLE BREEZES. ASSUMING CLOUDS ARE FAIRLY MINIMAL AS EXPECTED...THIS SHOULD ALLOW TEMPS TO DROP OFF RATHER EFFICIENTLY AND BASED ON MET/MAV GUIDANCE BLEND LOWERED LOWS 1-5 DEGREES ACROSS THE AREA...NOW AIMING FOR MID-UPPER 20S NORTHEAST TO LOW 30S SOUTHWEST. WEDNESDAY...WE CONTINUE TO SEE ESSENTIALLY ZERO RISK OF PRECIP...AS THE HEART OF THE MID-UPPER RIDGE AXIS SLIDES OVER THE CENTRAL PLAINS...BETWEEN A DEEP EASTERN CONUS TROUGH AND THE NEXT UPSTREAM SHORTWAVE OFF THE PACIFIC NORTHWEST COAST. AT THE SURFACE...SOUTHERLY BREEZES WILL PICK UP A BIT BEHIND THE DEPARTING RIDGE AXIS AND IN RESPONSE TO A MODEST HIGH PLAINS LEE TROUGH...AND NUDGED UP SUSTAINED SPEEDS TO AT LEAST 15 MPH DURING THE AFTERNOON. THESE SOUTH BREEZES SHOULD GIVE TEMPS ANOTHER UPWARD BOOST VERSUS THE PREVIOUS DAY. ALTHOUGH PLAYED IT SOMEWHAT CONSERVATIVE AND STAYED AT LEAST 2-4 DEGREES COOLER THAN THE RAW NAM SOLUTION...DID INCREASE PREVIOUS HIGHS GENERALLY 2 DEGREES NOW AIMING FOR A RANGE FROM LOW 60S EAST TO UPPER 60S/LOW 70S WEST. WEDNESDAY NIGHT...FLOW TRANSITIONS TO QUASI-ZONAL OR EVEN SLIGHTLY SOUTHWESTERLY AS THE CENTER OF THE MID-UPPER RIDGE AXIS SLIDES EAST. WITH THE EXPECTATION OF A LEAST LIGHT BUT STEADY SOUTHERLY BREEZES IN MOST AREAS...AM CALLING FOR A BIT WARMER NIGHT THAN TUESDAY NIGHT...AND KEPT LOWS CLOSE TO PREVIOUS FORECAST WITH MOST AREAS HOLDING UP IN THE 37-41 RANGE. .LONG TERM...THURSDAY THROUGH SUNDAY. MAIN CHALLENGES INCLUDE PRECIPITATION CHANCES AND TYPE ALONG WITH TEMPERATURES. UPPER PATTERN WILL BE IN THE PROCESS OF AMPLIFICATION FOR THE LONG TERM AS A MAJOR PATTERN SHIFT OCCURS. MODELS ARE IN GOOD AGREEMENT WITH THIS PATTERN SHIFT...BUT DO HAVE SOME MINOR DIFFERENCES. WE BEGIN THURSDAY WITH A DEEPENING EASTERN PACIFIC TROUGH AND PLAINS RIDGE. THIS PLACES US IN A VERY MILD REGIME TO BEGIN THE LONG TERM. THESE FEATURES WILL TRANSLATE EAST OVER TIME AND BY SATURDAY...THE ROBUST DIGGING LONGWAVE TROUGH WILL BE PROMINENT OVER THE INTERMOUNTAIN WEST. SATURDAY COULD TURN OUT TO BE QUITE WARM AHEAD OF THE ASSOCIATED COLD FRONT FROM THE TROUGH THAT IS EXPECTED TO ARRIVE BY SATURDAY NIGHT. THEREFORE I INCREASED HIGH TEMPERATURES ON SATURDAY COMPARED TO ALLBLEND INITIALIZATION. THERE COULD BE SOME SHOWER AND EVEN THUNDERSTORM ACTIVITY IN THE SOUTHEASTERN CWA WHERE MUCAPES WOULD SUPPORT THIS...BUT IT APPEARS FOR NOW THAT MOST OF ANY PRECIPITATION SHOULD FALL SATURDAY NIGHT ALONG AND BEHIND THE COLD FRONT. BY THE TIME WE GET COLD ENOUGH FOR SNOW...QPF SHOULD BE LIMITED...SO NOT LOOKING FOR MUCH ACCUMULATION. THE GFS SWINGS A CLOSED LOW AT 700 MB OVER THE CWA FOR SATURDAY NIGHT WHICH COULD MEAN MORE SNOW...BUT I AM NOT BUYING IN TO THIS AT THIS TIME. I INCREASED WIND SPEEDS SIGNIFICANTLY ON SATURDAY NIGHT AND SUNDAY AS STRONG COLD AIR ADVECTION IS ANTICIPATED FOR SATURDAY NIGHT AND SUNDAY BEHIND THE LONGWAVE TROUGH MOVING EAST. THE TEMPERATURE DROP WILL LIKELY BE TREMENDOUS BETWEEN SATURDAY AND SUNDAY AND I HAVE LOWERED TEMPERATURES FROM ALLBLEND INITIALIZATION FOR SUNDAY. IF CLOUDS STICK AROUND FOR A SIGNIFICANT PORTION OF THE DAY ON SUNDAY...WE VERY WELL MAY STRUGGLE TO GET OUT OF THE 20S...AND COUPLED WITH A STRONG NORTHWEST WIND...THIS COULD BE QUITE AN UNCOMFORTABLY COLD DAY...EVEN FOR NOVEMBER STANDARDS. && .PREV DISCUSSION... /ISSUED 1059 PM CST SUN NOV 4 2012/ AVIATION...06Z KGRI TAF. MVFR CONDITIONS TO CONTINUE THROUGH 10Z...WITH IFR CONDITIONS FORECAST 10Z-14Z. VFR CONDITIONS ARE THEN EXPECTED 14Z THROUGH THE END OF THE TAF PERIOD. STRATUS WILL PERSIST AT THE TERMINAL TONIGHT...WITH CEILINGS AS LOW AS 900FT AGL CURRENTLY FORECAST. SOME GUIDANCE ALSO SUGGESTS THERE MAY BE ENOUGH LOW LEVEL MOISTURE AND TURBULENT MIXING FOR LIGHT DRIZZLE FORMATION...AND WILL KEEP THE VISIBILITY AT 6SM 10-14Z AS A RESULT. THE SURFACE WIND WILL REMAIN FROM THE NORTH/NORTHWEST THROUGH THE TAF PERIOD...INTENSIFYING TO NEAR 16KTS AND GUSTING TO AROUND 22KTS 14Z ONWARD. THERE IS A LOW POSSIBILITY OF LLWS DEVELOPMENT TONIGHT AS THE WIND JUST ABOVE THE BOUNDARY LAYER INCREASE TO NEAR 35KTS AND THE SURFACE WIND REMAINS NEAR 5KTS. WILL LEAVE ANY MENTION OF LLWS OUT OF THE TAF FOR THE TIME BEING AS IT APPEARS WIND SHEAR SHOULD REMAIN UNDER CRITERIA...BUT STILL SOMETHING TO MONITOR UNTIL THE SURFACE WIND INCREASES LATER TONIGHT. && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$ SHORT TERM...PFANNKUCH LONG TERM...HEINLEIN AVIATION...BRYANT
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AREA FORECAST DISCUSSION
NWS GOODLAND KS
256 PM MST MON NOV 5 2012 .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 112 PM MST MON NOV 5 2012 LATEST WATER VAPOR AND RUC ANALYSIS DEPICT AN UPPER LEVEL RIDGE OVER THE WEST COAST...A SHORT WAVE TROUGH OVER SOUTHWEST CANADA WITH HIGH CLOUDS AHEAD OF IT OVER MONTANA SOUTH INTO COLORADO AND KANSAS. ANOTHER SHORT WAVE TROUGH WAS LOCATED OVER EASTERN OKLAHOMA AND CONTINUES TO DEEPEN. AT THE SURFACE A WARM FRONT WAS IN PLACE ALONG THE KS/CO BORDER NORTH INTO FAR SOUTHWEST SOUTH DAKOTA THANKS TO THE DOWNSLOPE WINDS COMING OFF THE ROCKIES. TONIGHT A SHORT WAVE RIDGE IN BETWEEN THE TROUGH OVER CANADA AND THE ONE TO OUR SOUTHEAST WILL MOVE OVER THE AREA. AT THE SURFACE A TROUGH WILL MOVE IN AHEAD OF THE UPPER LEVEL RIDGE. WINDS WILL SHIFT WEST WITH THE TROUGH PASSAGE THEN TURN BACK NORTH BEHIND IT. WITH A DRY ENVIRONMENT IN PLACE THE TROUGH PASSAGE WILL BE DRY. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 256 PM MST MON NOV 5 2012 FORECAST CONCERNS WILL BE THE AMOUNT OF WARMUP/FIRE WEATHER CONCERNS WEDNESDAY THROUGH FRIDAY FOLLOWED BY COLDER TEMPERATURES/CHANCE OF PRECIPITATION NEXT WEEKEND. SATELLITE SHOWING AN AMPLIFIED/AMPLIFYING AND ACTIVE FLOW FROM THE PACIFIC INTO THE WESTERN ATLANTIC. SYSTEMS TO NOTE...DEEPENING SOON TO BE STRONG SYSTEM DIGGING INTO THE EASTERN PORTION OF THE COUNTRY WITH VERY STRONG SYSTEM MOVING/DEVELOPING IN SOUTHERN CANADA AT THIS TIME. DRY AIR MASS CURRENTLY RESIDES OVER THE AREA. AT JET LEVEL...THE NAM FOLLOWED BY THE GFS WAS DOING THE BEST ON THE VERY STRONG THAT RUNS FROM THE GULF OF ALASKA AND ON THE WEST SIDE OF DEVELOPING EASTERN CONUS SYSTEM. AT MID LEVELS...THE GFS WAS DOING A LITTLE BETTER THAN EVERYTHING ELSE. THE SREF AND NAM WERE DOING BEST ON THE SURFACE WIND AND PRESSURE FIELD. THE NAM...GFS AND CANADIAN WERE DOING BEST AT THIS TIME ON THE LOW LEVEL THERMAL FIELD. TUESDAY NIGHT...LITTLE CLOUD COVER AND LIGHT WINDS...ESPECIALLY IN THE EAST...WILL ALLOW TEMPERATURES TO FALL BELOW GUIDANCE. MINS RECENTLY HAVE FALLING WELL BELOW NWP. WENT IN THAT DIRECTION AND CLOSER TO THE GEM 2 METER TEMPERATURES. WEDNESDAY/WEDNESDAY NIGHT...DURING THE DAY THE SURFACE RIDGE PULLS AWAY WITH A CHILLY START...ESPECIALLY IN THE EAST. NEWER NAM IS LESS AGGRESSIVE WITH THE DOWNSLOPE COMPONENT. HOWEVER...WILL HAVE PLENTY OF SUN AND WESTERLY FLOW ALOFT. KEPT TEMPERATURES ABOUT THE SAME EXCEPT WARMING THEM UP A TOUCH. THE WIND FIELD LOOKS TO BE A LITTLE LIGHT...ESPECIALLY IN THE EAST. AS TROUGH LINE PASSES THROUGH THE TEMPERATURES WILL DROP WITH THEM WARMING UP AS DOWNSLOPE WINDS INCREASE BEHIND THE TROUGH. SO WILL BE A LITTLE TRICKY. THURSDAY...MODELS ALL OVER THE PLACE ON BOUNDARY PLACEMENT AND TIMING AND RESULTING LOW LEVEL TEMPERATURES. CONSIDERING THE EXPECTED FLOW ALOFT...THE MODELS MAY BE RUSHING THINGS A LITTLE BIT. AT THIS TIME...DID A COMPROMISE BETWEEN THE WARMEST AND COOLEST TEMPERATURES BUT DEFINITELY COULD SEE IT BEING WARMER. THURSDAY NIGHT THROUGH MONDAY...MAJOR FEATURE OF INTEREST IS HOW THE DEVELOPING WESTERN TROUGH WILL AFFECT THE WEATHER. THE MODELS AND ENSEMBLES HAVE THE SAME GENERAL IDEA OF AN ELONGATED TROUGH WITH THE STRONGEST/BEST DYNAMICS MUCH FURTHER NORTH AND SPLITTING OFF THE WEAKER SOUTHERN END FURTHER SOUTH LEAVING OUR AREA IN THE MIDDLE. MODELS DO DIFFER ON THE SPEED OF THE TROUGH WITH MORE SUPPORT FOR A SLOWER ARRIVAL. TEMPERATURES THURSDAY NIGHT WILL BE RATHER TRICKY. COLD FRONT THAT IS EXPECTED TO MOVE THROUGH SOMETIME ON THURSDAY IS EXPECTED TO RETURN NORTH AS A WARM FRONT THURSDAY NIGHT INTO FRIDAY. MODEL IN GENERAL AGREEMENT ON FRIDAY WITH THE FRONT NEAR OR NORTH OF THE FORECAST AREA BY LATE IN THE DAY. OVER THE SOUTHERN HALF TO TWO THIRDS...MODELS AGREE ON VERY WARM 850 MB TEMPERATURES. WILL HAVE DEEP SOUTHWEST FLOW ALOFT. AT THIS TIME DO NOT EXPECT THICK CLOUD COVER. AS A RESULT OF THAT AND COLLABORATION...WARMED UP MAXES. THIS WARM UP STILL MAY NOT BE ENOUGH. FRIDAY NIGHT INTO SATURDAY THE FRONT COMES BACK SOUTH AS A COLD FRONT. SOME DISCREPANCY ON TIMING BUT THERE LOOKS TO BE A THICKENING CLOUD DECK AND DEVELOPING PRECIPITATION THROUGH THE DAY. SO LEFT THE INHERITED INIT ALONE. VERY COLD TEMPERATURES FOLLOWING ESPECIALLY FOR SATURDAY NIGHT INTO SUNDAY NIGHT. INIT GRIDS LOOK FINE BUT DID MAKE A MINOR ADJUSTMENT DOWN. SATURDAY...ESPECIALLY FROM THE AFTERNOON...INTO SUNDAY LOOKS TO BE OUR CHANCE FOR PRECIPITATION. ONLY CONCERN NOW IS IF THE SLOWER SOLUTIONS PREVAIL...THE PRECIPITATION COULD START LATER IN THE DAY ON SATURDAY AND CONTINUE THROUGH MORE OF SUNDAY. DESPITE THE BRUNT OF THE LIFT BEING FURTHER NORTH...RIGHT REAR QUADRANT OF JET...VERY STRONG PV ANOMALY...AND STRONG CO-LOCATED MESOSCALE FORCING LOCATED WITH FAVORABLE THETA-E LAPSE RATES...DO SUPPORT LIGHT PRECIPITATION OCCURRING. THINK WE WILL GET SOMETHING JUST NOT SURE HOW MUCH. AM CONCERNED AND WILL HAVE TO BE WATCHED CAREFULLY IN UPCOMING FORECASTS OF BANDED PRECIPITATION DEVELOPING OVER THE AREA. KEPT THE PHASE RAIN SATURDAY AFTERNOON AND SWITCHED IT OVER TO ALL SNOW SATURDAY NIGHT. DEPENDING ON HOW LONG THE PRECIPITATION LINGERS INTO SUNDAY...COULD BE ALL SNOW OR A RAIN AND SNOW MIXTURE. FOR THE PRECIPITATION KEPT WHAT THE INIT GRID PRODUCED. REMAINDER OF THE FORECAST IS DRY. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 1044 AM MST MON NOV 5 2012 VFR CONDITIONS FORECAST THROUGH THE PERIOD. LIGHT TO BREEZY NORTHWEST WINDS WILL TURN TO THE WEST TONIGHT AS A SURFACE TROUGH MOVES THROUGH. BEHIND THE TROUGH WINDS WILL INCREASE A FEW KNOTS AND TURN BACK TO THE NORTHWEST AS A SURFACE HIGH PRESSURE MOVES INTO THE AREA. && .FIRE WEATHER... ISSUED AT 256 PM MST MON NOV 5 2012 ON WEDNESDAY...RELATIVE HUMIDITIES WILL BECOME LOW. HOWEVER THE WIND FIELD LOOKS TO BE TOO LIGHT SO DO NOT EXPECT ANY FIRE WEATHER HIGHLIGHTS. ON FRIDAY...THIS DAY WILL HAVE TO BE WATCHED CAREFULLY. RELATIVE HUMIDITIES BE SOUTH OF THE WARM FRONT. WINDS WILL ALSO PICK UP IN THE SAME AREA. IF WARM FRONT IS FASTER MOVING NORTH AND THE WINDS END UP STRONGER...THERE MAY BE A NEED FOR A FIRE WEATHER HIGHLIGHT. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...JTL LONG TERM...BULLER AVIATION...JTL FIRE WEATHER...BULLER
AREA FORECAST DISCUSSION
NWS GOODLAND KS
115 PM MST MON NOV 5 2012 .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 112 PM MST MON NOV 5 2012 LATEST WATER VAPOR AND RUC ANALYSIS DEPICT AN UPPER LEVEL RIDGE OVER THE WEST COAST...A SHORT WAVE TROUGH OVER SOUTHWEST CANADA WITH HIGH CLOUDS AHEAD OF IT OVER MONTANA SOUTH INTO COLORADO AND KANSAS. ANOTHER SHORT WAVE TROUGH WAS LOCATED OVER EASTERN OKLAHOMA AND CONTINUES TO DEEPEN. AT THE SURFACE A WARM FRONT WAS IN PLACE ALONG THE KS/CO BORDER NORTH INTO FAR SOUTHWEST SOUTH DAKOTA THANKS TO THE DOWNSLOPE WINDS COMING OFF THE ROCKIES. TONIGHT A SHORT WAVE RIDGE IN BETWEEN THE TROUGH OVER CANADA AND THE ONE TO OUR SOUTHEAST WILL MOVE OVER THE AREA. AT THE SURFACE A TROUGH WILL MOVE IN AHEAD OF THE UPPER LEVEL RIDGE. WINDS WILL SHIFT WEST WITH THE TROUGH PASSAGE THEN TURN BACK NORTH BEHIND IT. WITH A DRY ENVIRONMENT IN PLACE THE TROUGH PASSAGE WILL BE DRY. TUESDAY WILL BE SIMILAR TO TODAY. WINDS WILL BE LIGHT AS A SURFACE HIGH BUILDS INTO THE AREA. TEMPERATURES WILL BE IN THE MID 60S TO LOW 70S. .LONG TERM...(THURSDAY THROUGH SUNDAY) ISSUED AT 218 AM MST MON NOV 5 2012 FORECAST AREA WILL BEGIN THE PERIOD UNDER SOUTHWEST FLOW ALOFT WITH AN UPPER LOW AND ASSOCIATED TROUGH IN THE PACIFIC NORTHWEST. THIS TROUGH WILL SLOWLY MOVE EAST INTO THE NORTHERN AND CENTRAL PLAINS AND WILL BEGIN TO IMPACT THE AREA SATURDAY AFTERNOON AS A COLD FRONT MOVES THROUGH. FOR SATURDAY NIGHT THROUGH SUNDAY NIGHT EXPECT MUCH COLDER TEMPERATURES COMPARED TO THOSE RECENTLY EXPERIENCED AS WELL AS AN INCREASING CHANCE FOR LIGHT PRECIPITATION. SOME RAIN SHOWERS ARE POSSIBLE SATURDAY WITH A GRADUAL CHANGEOVER TO SNOW FROM NORTHWEST TO SOUTHEAST SATURDAY NIGHT AS COLDER AIR MOVES IN. FOR SUNDAY MOST LIKELY PRECIP TYPE WOULD BE LIGHT SNOW. PRECIPITATION ENDS BY SUNDAY AS THE SYSTEM EXITS THE AREA. HIGH TEMPERATURES THURSDAY MID 60S NORTH MID 70S SOUTH PER GFS/ECMWF 850 TEMPERATURES. ON FRIDAY 850 TEMPERATURES WARM QUITE A BIT FROM SOUTHWEST TO NORTHEAST AS WARM FRONT LIFTS NORTHEAST AND DRY SOUTHWEST WINDS DEVELOP. PER COORDINATION WITH SURROUNDING OFFICES HAVE WARMED READINGS QUITE A BIT WITH 65 TO 70 ALONG THE KS/NE BORDER (NOT AS CONFIDENT IN WARMUP GIVEN WARM FRONT POSITION) AND MID TO UPPER 70S ELSEWHERE. CANT RULE OUT A FEW 80 DEGREE READINGS. RECORD HIGHS ARE POSSIBLE...MOST LIKELY BURLINGTON AND HILL CITY IF EVERYTHING WORKS OUT PERFECTLY. FOR SATURDAY WONT MAKE ANY CHANGES TO CURRENT FORECAST OF AROUND 50 NORTH TO NEAR 70 FAR EAST AS THE FRONTAL TIMING WILL BE KEY TO THE FORECAST. FINALLY FOR SUNDAY MUCH COLDER WITH HIGHS ONLY IN THE MID 30S TO LOW 40S. WILL NEED TO WATCH WINDS FOR FRIDAY AFTERNOON. 850 SOUTHWEST WINDS GENERALLY 25 TO NEAR 35 KTS ALONG/EAST OF THE STATE LINE WHICH IF TRANSLATE TO THE SFC WILL CREATE CRITICAL/NEAR CRITICAL FIRE WEATHER CONDITIONS AS CURRENT RH VALUES DROP INTO THE 20-25 PERCENT RANGE ACROSS THE SOUTHWEST 1/2 OF THE AREA. POST FRONTAL WINDS SATURDAY AFTERNOON MAY BE ON THE LOW SIDE AS WELL GIVEN 850 WINDS. COULD SEE GUSTS 25-30 MPH WHICH IS A BIT HIGHER THEN CURRENTLY ADVERTISED. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 1044 AM MST MON NOV 5 2012 VFR CONDITIONS FORECAST THROUGH THE PERIOD. LIGHT TO BREEZY NORTHWEST WINDS WILL TURN TO THE WEST TONIGHT AS A SURFACE TROUGH MOVES THROUGH. BEHIND THE TROUGH WINDS WILL INCREASE A FEW KNOTS AND TURN BACK TO THE NORTHWEST AS A SURFACE HIGH PRESSURE MOVES INTO THE AREA. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...JTL LONG TERM...DDT AVIATION...JTL
AREA FORECAST DISCUSSION
NWS WICHITA KS
1141 AM CST MON NOV 5 2012 .AVIATION...18Z TAFS KRSL/KSLN/KHUT/KICT/KCNU AVIATION CONCERNS WILL BE HOW QUICK TO CLEAR OUT THE MVFR CIGS TODAY. A WEAK COLD FRONT CAME THROUGH LAST EVENING AND CURRENTLY STRETCHES FROM CENTRAL MO INTO THE ARKLATEX REGION. MVFR CIGS OVERSPREAD MUCH OF THE AREA THIS MORNING AND HAVE RECENTLY STARTED TO DECREASE FROM WEST TO EAST OVER THE LAST COUPLE OF HOURS. CONFIDENCE IS FAIRLY HIGH THAT BY 21Z MOST OF THE CIGS WILL BE AT OR ABOVE 3,000FT WITH KCNU KEEPING THE CLOUDS AROUND INTO THE EARLY EVENING HOURS. ANOTHER SHORTWAVE IS EXPECTED TO DIVE ACROSS THE MISSISSIPPI VALLEY LATE TONIGHT INTO TUE AFTERNOON AND WILL DRAG ANOTHER WEAK COLD FRONT ACROSS THE AREA. HOWEVER THIS FRONT IS NOT EXPECTED TO BRING THE LOWER CIGS THAN THE MOST RECENT ONE DID. LAWSON && .PREV DISCUSSION... /ISSUED 1049 AM CST MON NOV 5 2012/ UPDATE... UPDATED TO TWEAK TEMPS AND CLOUD COVER HAVE UPDATED TO KEEP UP WITH THE INCREASING CLOUD TRENDS. IN ADDITION DROPPED MAXES A COUPLE DEGREES BASED ON CURRENT TRENDS. THE REMAINDER OF THE FORECAST LOOKS ON TRACK. LAWSON PREV DISCUSSION... /ISSUED 534 AM CST MON NOV 5 2012/ AVIATION...12Z TAFS KRSL/KSLN/KHUT/KICT/KCNU POTENTIAL FOR MVFR CEILINGS AT ALL SITES DURING THE DAYLIGHT HOURS AS LOW LEVEL COLD AIR ADVECTION SPREADS LOW CLOUDS INTO THE AREA. NAM WAS STRUGGLING WITH WESTERN EXTEND OF CURRENT LOW CLOUDS...WITH CURRENT RUC LOOKING MUCH BETTER. WILL BASE CLOUD FORECAST ON THE RUC LOW LEVEL MOISTURE PROFILES THIS MORNING...AND THEN TRANSITION TO NAM DURING THE AFTERNOON. WILL GO BROKEN-OVERCAST AT ALL SITES...BUT COULD SEE KRSL/KHUT ONLY GOING BROKEN-OVERCAST FOR A BRIEF PERIOD. CEILINGS SHOULD INCREASE A TAD DURING THE DAY. GUSTY NORTH WINDS AND CLOUDS SHOULD BOTH DIMINISH THIS AFTERNOON. HOWEVER ANOTHER WEAK SHORTWAVE WILL LIKELY SPREAD A MID LEVEL CLOUD DECK ACROSS ALL SITES OVERNIGHT. -HOWERTON PREV DISCUSSION... /ISSUED 315 AM CST MON NOV 5 2012/ DISCUSSION... THE MAIN FORECAST CHALLENGES ARE THE TEMPERATURES TOWARD THE END OF THE WORK WEEK AND THE COLD FRONTAL PASSAGE SATURDAY. SYNOPSIS: MUCH LIKE THE LAST FEW DAYS THE CONUS WEATHER PATTERN HAS CHANGED LITTLE...WITH A LARGE...BROAD TROUGH ACROSS THE EASTERN HALF OF THE COUNTRY AND A RIDGE ACROSS THE WESTERN HALF. THERE ARE MULTIPLE DISTURBANCES MOVING AROUND THE TROUGH OVER THE EAST. ONE OF THE DISTURBANCES IS DIVING ACROSS THE EASTERN HALVES OF NEBRASKA AND KANSAS...AND THIS WAVE HAS PUSHED A WEAK FRONT THROUGH THE AREA. WINDS ARE BECOMING NORTHWESTERLY. THE WINDS THIS MORNING AND THE CLOUD COVER ARE HELPING TO KEEP TEMPERATURES A BIT WARMER. TODAY - WEDNESDAY: THE WORK WEEK WILL HAVE A TRANQUIL BEGINNING. THE FRONT THAT WENT THROUGH LATE LAST NIGHT/EARLY THIS MORNING WILL CONTINUE TO PUSH EASTWARD WITH HIGH PRESSURE QUICKLY SLIDING IN BEHIND IT. THE UPPER PV WAVE IS STILL CLOSE ENOUGH THAT SCATTERED SHOWERS ARE POSSIBLE ACROSS EXTREME SOUTHEASTERN KANSAS THIS MORNING. NOT EXPECTING MUCH IN THE WAY OF ACCUMULATION...BUT CANNOT RULE OUT SPRINKLES AND A SHOWER OR TWO...ESPECIALLY AFTER SPRITZ AND SPRINKLES WERE REPORTED SUNDAY AFTERNOON ACROSS THE AREA. AFTER THE CHANCE THIS MORNING...THE FORECAST REMAINS DRY UNTIL THE END OF THE WEEK. ANOTHER DISTURBANCE WILL DIVE SOUTHEAST INTO THE BASE OF THE TROUGH TUESDAY NIGHT/WEDNESDAY AND WILL PULL YET ANOTHER VERY WEAK FRONT ACROSS THE AREA...MAINLY RESULTING IN A WIND SHIFT. SURFACE HIGH PRESSURE WILL BUILD AND SLIDE EASTWARD WEDNESDAY. TEMPERATURES WILL BE VERY SEASONAL...WITH THE COOLEST TEMPS TODAY AND WARMING INTO THE 70S FOR TUESDAY AND WEDNESDAY...5 TO 10 DEGREES ABOVE NORMAL FOR EARLY NOVEMBER. THURSDAY - SUNDAY: THIS PERIOD CONTINUES TO BE THE MOST INTERESTING OF THE FORECAST WITH A LARGE CHANGE COMING TO THE PLAINS. THE UPPER RIDGE OVER THE WEST WILL TRANSLATE EASTWARD OVER THE PLAINS WITH A LARGE POTENT PV ANOMALY DIVING SOUTH FROM ALASKA APPROACHING FROM THE WEST. THE MEDIUM RANGE GUIDANCE HAS BEEN IN GOOD AGREEMENT FOR THE LAST FEW DAYS REGARDING THIS SYSTEM WHICH GIVES CONFIDENCE TO THE FORECAST. THE SOUTHWESTERLY UPPER LEVEL FLOW WILL AID LEE TROUGHING TO DEEPEN WITH STOUT GRADIENT WINDS EXPECTED FROM THURSDAY - SATURDAY. THE COMBINATION OF THE WARM AIR ADVECTION AND STRONG SOUTH WINDS WILL HELP TEMPERATURES RISE 10-20 DEGREES ABOVE NORMAL...WITH SOME AREAS POSSIBLY REACHING THE LOW 80S...ALTHOUGH HAVE KEPT THE FORECASTED TEMPS IN THE UPPER 70S FOR NOW. RECORDS LOOK SAFE FOR THURSDAY...BUT THEY COULD BE IN JEOPARDY FOR FRIDAY AND SATURDAY AT A FEW LOCATIONS IF THINGS STAY ON TRACK. THE COLD FRONT IS EXPECTED TO TRAVERSE THE AREA SATURDAY NIGHT/SUNDAY MORNING...AND FOR BEING AT 144+ HOURS...THE GUIDANCE IS IN SHOCKINGLY GOOD AGREEMENT ON TIMING. HOWEVER...DESPITE THE SIMILARITIES THERE ARE SOME DIFFERENCES IN THE GUIDANCE...ESPECIALLY REGARDING THE PRECIPITATION POTENTIAL. THE GFS CONTINUES TO BE MORE BULLISH WITH WARM SECTOR PRECIP THAN THE ECMWF. HAVE KEPT SLIGHTS FOR FRIDAY AHEAD OF THE FRONT...BUT THINK THE MAJORITY AND BEST CHANCE WE HAVE FOR PRECIPITATION WILL BE WITH THE CONVERGENCE ALONG THE FRONT AND THE MAIN UPPER DYNAMICS AS IT MOVES ACROSS THE AREA. REGARDLESS...THIS IS THE BEST CHANCE FOR RAIN IN THE FORECAST. THIS SYSTEM WILL BRING SIGNIFICANT CHANGES WITH ARCTIC AIR MOVING INTO PLACE BEHIND THE FRONTAL PASSAGE. TEMPERATURES SATURDAY NIGHT AND SUNDAY WILL BE SIGNIFICANTLY COLDER...HIGHS IN THE 30S/40S AND LOWS IN THE 20S. WITH THESE TEMPS AND PRECIPITATION POTENTIAL...SOME AREAS OF KANSAS MAY SEE SNOW WITH THIS SYSTEM. BILLINGS FIRE WEATHER... DRY CONDITIONS AND GUSTY WINDS WILL CAUSE FIRE WEATHER TO BE A CONCERN...ESPECIALLY TOWARD THE END OF THE WEEK. STRONG NORTHWESTERLY WINDS AND LOW DEWPOINTS TODAY WILL CAUSE VERY HIGH FIRE DANGER TO BE A CONCERN ACROSS MUCH OF CENTRAL AND SOUTH CENTRAL KANSAS. A POTENT WEATHER SYSTEM WILL APPROACH FOR THE WEEKEND AND LEE TROUGHING WILL CAUSE GRADIENT WINDS TO INCREASE THURSDAY THROUGH SATURDAY. VERY HIGH GRASSLAND FIRE DANGER IS EXPECTED THURSDAY THROUGH SATURDAY. SOME AREAS OF CENTRAL KANSAS WILL HAVE THE POTENTIAL FOR EXTREME GRASSLAND FIRE DANGER SATURDAY AHEAD OF THE FRONTAL PASSAGE. THINGS COULD CHANGE WITH THE FORECAST AND TIMING...SO KEEP AN EYE ON THINGS. BILLINGS CLIMATE... RECORD HIGHS FOR THURSDAY NOVEMBER 8TH, 2012 WICHITA....86 IN 2006 RUSSELL....89 IN 2006 SALINA.....89 IN 2006 CHANUTE....84 IN 2006 RECORD HIGHS FOR FRIDAY NOVEMBER 9TH, 2012 WICHITA....82 IN 2006 RUSSELL....78 IN 1999 SALINA.....80 IN 1999 CHANUTE....82 IN 2006 RECORD HIGHS FOR SATURDAY NOVEMBER 10TH, 2012 WICHITA....77 IN 1927 RUSSELL....78 IN 1956 SALINA.....82 IN 1927 CHANUTE....78 IN 1911 BILLINGS AVIATION...06Z TAFS KRSL/KSLN/KHUT/KICT/KCNU AT THE MID-NGT HOUR A SLOW SE-MOVG COLD FRONT WAS KNOCKING ON THE DOOR AT KSLN & KHUT. NW WINDS IN THE FRONT`S WAKE WERE ONLY 5-10KTS & HAVE THEREFORE EASED ON WIND THROTTLE FOR ALL 5 TERMINALS FOR THE REMAINDER OF THE NGT. THE MORE SIGNIFICANT CHANGE IS THAT MVFR CIGS (~2,500FT) WILL VENTURE ACROSS THE KRSL & KSLN TERMINALS FROM 12Z-17Z. WITH THE SE MOVEMENT OF THE 925-850MB LOW THE MVFR CIGS SHOULD REMAIN NE OF THE KICT & KHUT TERMINALS. NW WINDS SUSTAINED ~17KTS/22MPH WITH GUSTS THAT MAY REACH ~25KTS ARE LIKELY FOR ALL 5 TERMINALS FROM ~15Z TIL LATE IN AFTERNOON. ES && .PRELIMINARY POINT TEMPS/POPS... WICHITA-KICT 56 35 72 38 / 0 0 0 0 HUTCHINSON 55 34 71 37 / 0 0 0 0 NEWTON 53 34 68 37 / 10 0 0 0 ELDORADO 54 33 69 36 / 10 0 0 0 WINFIELD-KWLD 57 35 70 39 / 0 0 0 0 RUSSELL 57 34 69 35 / 0 0 0 0 GREAT BEND 58 34 70 38 / 0 0 0 0 SALINA 54 35 69 37 / 0 0 0 0 MCPHERSON 54 34 71 37 / 0 0 0 0 COFFEYVILLE 54 36 67 37 / 20 0 0 0 CHANUTE 52 36 65 36 / 20 0 0 0 IOLA 51 37 64 37 / 20 0 0 0 PARSONS-KPPF 53 34 66 34 / 20 0 0 0 && .ICT WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS WICHITA KS
1049 AM CST MON NOV 5 2012 .UPDATE... UPDATED TO TWEAK TEMPS AND CLOUD COVER HAVE UPDATED TO KEEP UP WITH THE INCREASING CLOUD TRENDS. IN ADDITION DROPPED MAXES A COUPLE DEGREES BASED ON CURRENT TRENDS. THE REMAINDER OF THE FORECAST LOOKS ON TRACK. LAWSON && .PREV DISCUSSION... /ISSUED 534 AM CST MON NOV 5 2012/ AVIATION...12Z TAFS KRSL/KSLN/KHUT/KICT/KCNU POTENTIAL FOR MVFR CEILINGS AT ALL SITES DURING THE DAYLIGHT HOURS AS LOW LEVEL COLD AIR ADVECTION SPREADS LOW CLOUDS INTO THE AREA. NAM WAS STRUGGLING WITH WESTERN EXTEND OF CURRENT LOW CLOUDS...WITH CURRENT RUC LOOKING MUCH BETTER. WILL BASE CLOUD FORECAST ON THE RUC LOW LEVEL MOISTURE PROFILES THIS MORNING...AND THEN TRANSITION TO NAM DURING THE AFTERNOON. WILL GO BROKEN-OVERCAST AT ALL SITES...BUT COULD SEE KRSL/KHUT ONLY GOING BROKEN-OVERCAST FOR A BRIEF PERIOD. CEILINGS SHOULD INCREASE A TAD DURING THE DAY. GUSTY NORTH WINDS AND CLOUDS SHOULD BOTH DIMINISH THIS AFTERNOON. HOWEVER ANOTHER WEAK SHORTWAVE WILL LIKELY SPREAD A MID LEVEL CLOUD DECK ACROSS ALL SITES OVERNIGHT. -HOWERTON PREV DISCUSSION... /ISSUED 315 AM CST MON NOV 5 2012/ DISCUSSION... THE MAIN FORECAST CHALLENGES ARE THE TEMPERATURES TOWARD THE END OF THE WORK WEEK AND THE COLD FRONTAL PASSAGE SATURDAY. SYNOPSIS: MUCH LIKE THE LAST FEW DAYS THE CONUS WEATHER PATTERN HAS CHANGED LITTLE...WITH A LARGE...BROAD TROUGH ACROSS THE EASTERN HALF OF THE COUNTRY AND A RIDGE ACROSS THE WESTERN HALF. THERE ARE MULTIPLE DISTURBANCES MOVING AROUND THE TROUGH OVER THE EAST. ONE OF THE DISTURBANCES IS DIVING ACROSS THE EASTERN HALVES OF NEBRASKA AND KANSAS...AND THIS WAVE HAS PUSHED A WEAK FRONT THROUGH THE AREA. WINDS ARE BECOMING NORTHWESTERLY. THE WINDS THIS MORNING AND THE CLOUD COVER ARE HELPING TO KEEP TEMPERATURES A BIT WARMER. TODAY - WEDNESDAY: THE WORK WEEK WILL HAVE A TRANQUIL BEGINNING. THE FRONT THAT WENT THROUGH LATE LAST NIGHT/EARLY THIS MORNING WILL CONTINUE TO PUSH EASTWARD WITH HIGH PRESSURE QUICKLY SLIDING IN BEHIND IT. THE UPPER PV WAVE IS STILL CLOSE ENOUGH THAT SCATTERED SHOWERS ARE POSSIBLE ACROSS EXTREME SOUTHEASTERN KANSAS THIS MORNING. NOT EXPECTING MUCH IN THE WAY OF ACCUMULATION...BUT CANNOT RULE OUT SPRINKLES AND A SHOWER OR TWO...ESPECIALLY AFTER SPRITZ AND SPRINKLES WERE REPORTED SUNDAY AFTERNOON ACROSS THE AREA. AFTER THE CHANCE THIS MORNING...THE FORECAST REMAINS DRY UNTIL THE END OF THE WEEK. ANOTHER DISTURBANCE WILL DIVE SOUTHEAST INTO THE BASE OF THE TROUGH TUESDAY NIGHT/WEDNESDAY AND WILL PULL YET ANOTHER VERY WEAK FRONT ACROSS THE AREA...MAINLY RESULTING IN A WIND SHIFT. SURFACE HIGH PRESSURE WILL BUILD AND SLIDE EASTWARD WEDNESDAY. TEMPERATURES WILL BE VERY SEASONAL...WITH THE COOLEST TEMPS TODAY AND WARMING INTO THE 70S FOR TUESDAY AND WEDNESDAY...5 TO 10 DEGREES ABOVE NORMAL FOR EARLY NOVEMBER. THURSDAY - SUNDAY: THIS PERIOD CONTINUES TO BE THE MOST INTERESTING OF THE FORECAST WITH A LARGE CHANGE COMING TO THE PLAINS. THE UPPER RIDGE OVER THE WEST WILL TRANSLATE EASTWARD OVER THE PLAINS WITH A LARGE POTENT PV ANOMALY DIVING SOUTH FROM ALASKA APPROACHING FROM THE WEST. THE MEDIUM RANGE GUIDANCE HAS BEEN IN GOOD AGREEMENT FOR THE LAST FEW DAYS REGARDING THIS SYSTEM WHICH GIVES CONFIDENCE TO THE FORECAST. THE SOUTHWESTERLY UPPER LEVEL FLOW WILL AID LEE TROUGHING TO DEEPEN WITH STOUT GRADIENT WINDS EXPECTED FROM THURSDAY - SATURDAY. THE COMBINATION OF THE WARM AIR ADVECTION AND STRONG SOUTH WINDS WILL HELP TEMPERATURES RISE 10-20 DEGREES ABOVE NORMAL...WITH SOME AREAS POSSIBLY REACHING THE LOW 80S...ALTHOUGH HAVE KEPT THE FORECASTED TEMPS IN THE UPPER 70S FOR NOW. RECORDS LOOK SAFE FOR THURSDAY...BUT THEY COULD BE IN JEOPARDY FOR FRIDAY AND SATURDAY AT A FEW LOCATIONS IF THINGS STAY ON TRACK. THE COLD FRONT IS EXPECTED TO TRAVERSE THE AREA SATURDAY NIGHT/SUNDAY MORNING...AND FOR BEING AT 144+ HOURS...THE GUIDANCE IS IN SHOCKINGLY GOOD AGREEMENT ON TIMING. HOWEVER...DESPITE THE SIMILARITIES THERE ARE SOME DIFFERENCES IN THE GUIDANCE...ESPECIALLY REGARDING THE PRECIPITATION POTENTIAL. THE GFS CONTINUES TO BE MORE BULLISH WITH WARM SECTOR PRECIP THAN THE ECMWF. HAVE KEPT SLIGHTS FOR FRIDAY AHEAD OF THE FRONT...BUT THINK THE MAJORITY AND BEST CHANCE WE HAVE FOR PRECIPITATION WILL BE WITH THE CONVERGENCE ALONG THE FRONT AND THE MAIN UPPER DYNAMICS AS IT MOVES ACROSS THE AREA. REGARDLESS...THIS IS THE BEST CHANCE FOR RAIN IN THE FORECAST. THIS SYSTEM WILL BRING SIGNIFICANT CHANGES WITH ARCTIC AIR MOVING INTO PLACE BEHIND THE FRONTAL PASSAGE. TEMPERATURES SATURDAY NIGHT AND SUNDAY WILL BE SIGNIFICANTLY COLDER...HIGHS IN THE 30S/40S AND LOWS IN THE 20S. WITH THESE TEMPS AND PRECIPITATION POTENTIAL...SOME AREAS OF KANSAS MAY SEE SNOW WITH THIS SYSTEM. BILLINGS FIRE WEATHER... DRY CONDITIONS AND GUSTY WINDS WILL CAUSE FIRE WEATHER TO BE A CONCERN...ESPECIALLY TOWARD THE END OF THE WEEK. STRONG NORTHWESTERLY WINDS AND LOW DEWPOINTS TODAY WILL CAUSE VERY HIGH FIRE DANGER TO BE A CONCERN ACROSS MUCH OF CENTRAL AND SOUTH CENTRAL KANSAS. A POTENT WEATHER SYSTEM WILL APPROACH FOR THE WEEKEND AND LEE TROUGHING WILL CAUSE GRADIENT WINDS TO INCREASE THURSDAY THROUGH SATURDAY. VERY HIGH GRASSLAND FIRE DANGER IS EXPECTED THURSDAY THROUGH SATURDAY. SOME AREAS OF CENTRAL KANSAS WILL HAVE THE POTENTIAL FOR EXTREME GRASSLAND FIRE DANGER SATURDAY AHEAD OF THE FRONTAL PASSAGE. THINGS COULD CHANGE WITH THE FORECAST AND TIMING...SO KEEP AN EYE ON THINGS. BILLINGS CLIMATE... RECORD HIGHS FOR THURSDAY NOVEMBER 8TH, 2012 WICHITA....86 IN 2006 RUSSELL....89 IN 2006 SALINA.....89 IN 2006 CHANUTE....84 IN 2006 RECORD HIGHS FOR FRIDAY NOVEMBER 9TH, 2012 WICHITA....82 IN 2006 RUSSELL....78 IN 1999 SALINA.....80 IN 1999 CHANUTE....82 IN 2006 RECORD HIGHS FOR SATURDAY NOVEMBER 10TH, 2012 WICHITA....77 IN 1927 RUSSELL....78 IN 1956 SALINA.....82 IN 1927 CHANUTE....78 IN 1911 BILLINGS AVIATION...06Z TAFS KRSL/KSLN/KHUT/KICT/KCNU AT THE MID-NGT HOUR A SLOW SE-MOVG COLD FRONT WAS KNOCKING ON THE DOOR AT KSLN & KHUT. NW WINDS IN THE FRONT`S WAKE WERE ONLY 5-10KTS & HAVE THEREFORE EASED ON WIND THROTTLE FOR ALL 5 TERMINALS FOR THE REMAINDER OF THE NGT. THE MORE SIGNIFICANT CHANGE IS THAT MVFR CIGS (~2,500FT) WILL VENTURE ACROSS THE KRSL & KSLN TERMINALS FROM 12Z-17Z. WITH THE SE MOVEMENT OF THE 925-850MB LOW THE MVFR CIGS SHOULD REMAIN NE OF THE KICT & KHUT TERMINALS. NW WINDS SUSTAINED ~17KTS/22MPH WITH GUSTS THAT MAY REACH ~25KTS ARE LIKELY FOR ALL 5 TERMINALS FROM ~15Z TIL LATE IN AFTERNOON. ES && .PRELIMINARY POINT TEMPS/POPS... WICHITA-KICT 56 35 72 38 / 0 0 0 0 HUTCHINSON 55 34 71 37 / 0 0 0 0 NEWTON 53 34 68 37 / 10 0 0 0 ELDORADO 54 33 69 36 / 10 0 0 0 WINFIELD-KWLD 57 35 70 39 / 0 0 0 0 RUSSELL 57 34 69 35 / 0 0 0 0 GREAT BEND 58 34 70 38 / 0 0 0 0 SALINA 54 35 69 37 / 0 0 0 0 MCPHERSON 54 34 71 37 / 0 0 0 0 COFFEYVILLE 54 36 67 37 / 20 0 0 0 CHANUTE 52 36 65 36 / 20 0 0 0 IOLA 51 37 64 37 / 20 0 0 0 PARSONS-KPPF 53 34 66 34 / 20 0 0 0 && .ICT WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1211 PM EST MON NOV 5 2012 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 525 AM EST MON NOV 5 2012 WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL RIDGE INTO THE WRN CONUS AND A TROUGH OVER THE CENTRAL AND EAST. WEAK NRLY FLOW PREVAILED ACROSS THE NRN GREAT LAKES BTWN A CLOSED LOW OVER NRN QUEBEC AND A SHRTWV TROUGH INTO NW MISSOURI. A STRONGER UPSTREAM SHRTWV WAS MOVING QUICKLY EASTWARD INTO SRN ALBERTA. AT THE SFC...A RIDGE EXTENDED FROM NRN ONTARIO INTO CNTRL WI RESULTING IN WEAK ENE FLOW THROUGH UPPER MI. IR LOOP SHOWED LOW CLOUDS PERSISTING OVER THE CWA WITH MOISTURE TRAPPED BELOW THE INVERSION AROUND 2K-3K FT. A PATCH OF CLEAR SKIES NEAR ANJ/CIU HAS SLID TO THE SW AND MOSTLY FILLED BACK IN. RADAR INDICATED THAT THE ISOLD -SHSN/FLURRIES HAD AT LEAST TEMPORARILY ENDED. THE SURFACE HIGH WILL DRIFT TO THE SOUTHEAST ACROSS THE UPPER GREAT LAKES REGION. THE LIGHT ERLY 925 MB WINDS MAY ALLOW FOR SOME CLEARING OVER THE ERN CWA TODAY WITH DOWNSLOPE FLOW FROM N OF THE SAULT. IN ADDITION...DAYTIME MIXING SHOULD ALSO HELP ERODE THE CLOUDS. OVER THE WEST...UPSLOPE FLOW SHOULD HELP TO MAINTAIN THE OVERCAST CONDITIONS. 900 MB TEMPS AROUND -8C WILL PROVIDE ENOUGH INSTABILITY FOR THE CONTINUED POTENTIAL OF ISOLD -SHSN W AND N OF MARQUETTE INTO THE KEWEENAW THIS MORNING. BY AFTERNOON...WINDS WILL BECOME LIGHT SRLY...ENDING ANY -SHSN CHANCES. THE LOW CLOUDS WILL AGAIN KEEP TEMPS FROM CLIMBING BEYOND THE MID AND UPPER 30S. TONIGHT...PCPN ASSOCIATED WITH THE SHORTWAVE TROUGH DIVING FROM SRN MANITOBA INTO THE UPPER MS VALLEY WILL SPREAD INTO WRN LAKE SUPERIOR AND POSSIBLY INTO THE WEST HALF OF UPPER MI. NAM WET-BULB ZERO HEIGHT SUGGEST THAT PCPN STARTING OUT AS SNOW COULD BEGIN CHANGING OVER TO RAIN OVER THE WEST. THE BEST CHANCE FOR ANY MEASURABLE PCPN WILL ONLY BE OVER THE FAR WEST FROM IWD-CMX. ANY SNOW AMOUNTS WOULD ONLY AMOUNT TO A LIGHT COATING (FEW TENTHS) OVER THE HIGHER TERRAIN. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 525 AM EST MON NOV 5 2012 FCST MODELS HAVE SLOWED DOWN THE PROGRESS OF THE NEXT SYSTEM INFLUENCING THE UPPER GREAT LAKES...BY ROUGHLY 2-3HRS IN THE PAST COUPLE OF RUNS. EXPECT THE LOW TO PUSH ACROSS UPPER MICHIGAN TUESDAY AFTERNOON...AND SLOWLY EXIT TO THE SOUTHEAST TUESDAY NIGHT...MERGING WITH THE STRONGER LOW OFF THE MID ATLANTIC COAST ON WEDNESDAY. ONE TO TWO TENTH OF AN INCH OF LIQUID IS EXPECTED...MAINLY IN THE FORM OF RAIN. THE COOLER HIGHER ELEVATIONS OF N CENTRAL UPPER MI THAT SHOULD TOP OUT IN THE MID 30S TUESDAY SHOULD STAY IN THE MOSTLY IN THE FORM OF SNOW. STILL HAVE HALF OF AN INCH TO RIGHT AROUND AN INCH OF NEW SNOW FORECAST THROUGH TUESDAY EVENING...AS THE DGZ AROUND 600MB IS BRIEFLY ACCOMPANIED BY ENOUGH MOISTURE TO PRODUCE ACCUMULATING SNOW. S SFC TO 850MB WINDS OF 15-25KTS OVER N CENTRAL TO NE UPPER MI TUESDAY SHOULD KEEP DOWNSLOPE AREAS A COUPLE DEGREES WARMER. GIVEN THE FAIRLY CONSISTENT MODEL RUNS...A BLEND SEEMS REASONABLE FOR MUCH OF THE PERIOD. DRIER AIR WILL SLOWLY WORK IN WEDNESDAY AND STAY THROUGH AT LEAST THURSDAY NIGHT AS HIGH PRESSURE REMAINS IN CONTROL AT THE SFC AND ALOFT. SW FLOW WILL BE ON THE INCREASE AGAIN FRIDAY AFTERNOON AND EVENING AS THE SFC RIDGE WEAKENS OVER THE CWA AND THE APEX OF THE 500MB RIDGE EDGES JUST TO OUR E. WITH SOME OF THE WARMEST AIR WE HAVE HAD OVER THE CWA IN A COUPLE OF WEEKS /850MB TEMPS POSSIBLY BU TO 12C AT 00Z SUN OFF THE NEW 11/00Z ECMWF/. WITH ALL THE WARM AIR AND INCREASED LAPSE RATES KEPT THE POTENTIAL FOR TS SATURDAY INTO SUNDAY...BUT DID A BIT OF TAILORING TO ALIGN BETTER WITH THE LATEST MODEL DATA. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 1211 PM EST MON NOV 5 2012 WILL GO MORE PESSIMISTIC WITH THIS FORECAST AND KEEP MVFR CIGS IN THROUGH THE AFTERNOON AT ALL SITES. BY TONIGHT...GETS A BIT TRICKY WITH SOUTH WINDS DEVELOPING. THINKING RIGHT NOW IS CONDITIONS WILL GO VFR OUT AHEAD OF NEXT SYSTEM THAT ARRIVES LATE TONIGHT. WHEN PCPN STARTS...CONDITIONS WILL GO BACK TO MVFR CONDITIONS WITH A RASN MIXTURE. PUT IN SOME LLWS AT IWD LATE TONIGHT OUT AHEAD OF NEXT SYSTEM. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 525 AM EST MON NOV 5 2012 AS HIGH PRESSURE OVER NORTHWEST ONTARIO SLIDES SOUTHEAST THROUGH THE UPPER GREAT LAKES TODAY...EXPECT WINDS TO BE LIGHT AND LESS THAN 20KTS. A LOW PRESSURE SYSTEM MOVING THROUGH CENTRAL CANADA ON TUESDAY WILL SWEEP A SURFACE TROUGH ACROSS THE UPPER GREAT LAKES REGION AND BRING INCREASING SOUTHWESTERLY WINDS TO 20-30 KTS. A WEAK HIGH PRESSURE RIDGE WILL THEN SLIDE INTO THE UPPER GREAT LAKES WEDNESDAY AFTERNOON AND REMAIN INTO FRIDAY. A 29.5 INCH LOW PRESSURE SYSTEM DEVELOPING IN THE CENTRAL PLAINS ON FRIDAY IS EXPECTED TO LIFT NORTH INTO THE UPPER MISSISSIPPI VALLEY BY SATURDAY NIGHT. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLB LONG TERM...KF AVIATION...07 MARINE...JLB
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
318 PM CST MON NOV 5 2012 .SHORT TERM...TONIGHT THROUGH THURSDAY. MAIN FORECAST CONCERN IS SMALL CHANCE FOR SHOWERS IN OUR NORTHEAST OVERNIGHT. LATEST WATER VAPOR IMAGERY AND RAP 500MB ANALYSIS SHOW THE REGION IN NORTHWESTERLY FLOW ALOFT WITH SHORTWAVE ENERGY QUICKLY DROPPING THROUGH THE SOUTHERN CANADIAN PRAIRIE PROVINCES. ASSOCIATED SFC LOW PRESSURE AREA CONTINUES TO QUICKLY MOVE SOUTHEAST AHEAD OF THIS UPPER FEATURE WITH WIDESPREAD SHOWERS ACROSS NORTH DAKOTA. THESE FEATURES WILL CONTINUE THEIR SOUTHWARD PROGRESSION AND SHOULD BRUSH THE NORTHEASTERN COUNTIES OVERNIGHT...MAINLY AFTER 06Z. HAVE ADDED A SMALL CHANCE FOR SHOWERS AS MOISTURE PROFILES ARE SLOW TO SATURATE LOWER LEVELS. IN ADDITION...ASSOCIATED SFC COLD FRONT WILL PUSH THROUGH THE FORECAST AREA TUESDAY MORNING. GOOD MOMENTUM TRANSFER SHOULD ALLOW GUSTY CONDITIONS INTO TUESDAY AFTERNOON BEHIND THE FRONT. HIGH TEMPERATURES SHOULD ONLY TOP OUT IN THE LOWER 50S ACROSS THE NORTHEASTERN CWA WITH UPPER 50S IN THE SOUTHWEST. SFC HIGH PRESSURE QUICKLY BUILDS IN WEDNESDAY MORNING BRINGING CLEAR AND CALM CONDITIONS. A GRADUAL WARMING TREND WEDNESDAY INTO THURSDAY IS EXPECTED AS A WESTERN RIDGE BUILDS EAST OVER THE AREA AND RETURN FLOW DEVELOPS AROUND SFC HIGH PRESSURE. KERN .LONG TERM...THURSDAY NIGHT THROUGH MONDAY. LOOKS LIKE SOME ACTIVE WEATHER FOR THE WEEKEND WITH BIG SWINGS IN TEMPERATURES. THE EC/GFS/GEFS/CANADIAN ARE ALL IN FAIRLY GOOD AGREEMENT...WITH SOME TYPICALLY TIMING AND STRENGTH DIFFERENCES. THE FORECAST AREA WILL BE IN THE WARM SECTOR THURSDAY NIGHT WITH AN INVERTED TROF SETTLING INTO NORTHEAST NEBRASKA. THE GULF IS OPEN WITH H85 FLOW FROM TEXAS THROUGH THE PLAINS WITH THE DRY SLOT HEADING ACROSS NORTH CENTRAL KANSAS BY 12Z FRIDAY. THE SURFACE LOW INITIALLY OVER THE CENTRAL ROCKIES TRACKS NORTHEAST ALONG THE FRONT AND BY 18Z SATURDAY IS CENTERED SOMEWHERE BETWEEN EASTERN SOUTH DAKOTA/EASTERN NEBRASKA (GFS/EC/GEFS) OR MINNESOTA (CANADIAN). THE BULK OF THE PRECIPITATION WILL INITIALLY BE AHEAD OF...NORTH...AND TO THE WEST OF THE FORECAST AREA. SATURDAY NIGHT LOOKS TO BE THE BEST CHANCE FOR PRECIPITATION...ALTHOUGH THERE WILL BE LIFT/WAA DURING THE DAY SATURDAY. THE GFS HAS A SURGE OF HIGHER DEWPOINTS NEAR THE MISSOURI RIVER AND THEN LIFTING NORTH AND SHIFTING QUICKLY EAST. THE EC IS SLOWER WITH THE DEEP MOISTURE AND HOLDS ON TO THE HIGH 10 TO 12DEG C H85 DEWPOINTS. COMBINED WITH THE LIFT WITH THIS DYNAMIC SYSTEM THESE DIFFERENCES ACCOUNT FOR THE DIFFERENCES IN RESULTANT QPF WITH HIGHER PRECIPITATION AMOUNTS WITH THE EC. TEMPERATURES FRIDAY AND SATURDAY WILL BE IN THE 60S AND 70S AND MUCH COLDER FOR SUNDAY AND MONDAY WITH HIGHS IN THE 30S AND 40S. FOR NOW HAVE SOME CHANCE POPS SATURDAY AFTERNOON AND LIKELY POPS SATURDAY NIGHT AND DEPENDING ON IF THE SYSTEM SLOWS DOWN...SOME POPS INTO SUNDAY. WITH INSTABILITY AHEAD OF THE FRONT WILL INCLUDE THUNDER. THERE COULD BE A MIX IN THE NORTHEAST AS COLDER AIR WORKS INTO THE SYSTEM IN NORTHEAST NEBRASKA. SHOULD THERE BE LINGERING PRECIPITATION SUNDAY...THERE COULD BE A MIX OR MINOR ACCUMULATIONS SUNDAY. ZAPOTOCNY && .AVIATION... 18Z TAFS FOR KOFK...KLNK AND KOMA. IFR/MVFR CIGS BETWEEN FL005 AND FL015 WILL PERSIST MUCH OF THE AFTERNOON WITH ONLY GRADUAL IMPROVEMENT THROUGH 00Z. OCCASIONAL MVFR/IFR VSBYS IN DRIZZLE AND FOG ARE POSSIBLE ALONG THE MISSOURI RIVER NEAR KOMA THROUGH ABOUT 21Z. SOME IMPROVEMENT TO VFR CONDITIONS ARE LIKELY BETWEEN 00Z AND 03Z...BUT ANY CLEARING WILL LEAD TO IFR FOG FORMATION AFTER 06Z. DERGAN && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && $$
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1210 PM CST MON NOV 5 2012 .UPDATE...MADE A FEW MINOR CHANGES TO THE SKY COVER FORECAST...MAINLY TO DECREASE CLOUDS ACROSS SOUTHWEST ZONES BASED ON CURRENT TRENDS. THE HIGH TEMPERATURE FORECAST FOR TODAY LOOKS PRETTY GOOD AND SHOULD BE CLOSE...THEREFORE MADE NO CHANGES TO THE TEMPERATURE FORECAST. .AVIATION...18Z KGRI TAF. LOW CLOUDS ARE BEGINNING TO BREAK UP AND EXPECT VFR CONDITIONS AT KGRI TO RETURN BY MID AFTERNOON. THE NORTH WIND WILL BECOME LIGHT AND VARIABLE BY EARLY EVENING AND THEN SOUTHERLY BY LATE EVENING. THE WIND WILL VEER WITH TIME THROUGH THE OVERNIGHT HOURS EVENTUALLY BECOMING NORTHWEST BEHIND THE NEXT FRONTAL BOUNDARY TUESDAY MORNING. && .PREV DISCUSSION... /ISSUED 645 AM CST MON NOV 5 2012/ UPDATE...JUST SHIPPED A FAIRLY MINOR UPDATE...MAINLY TO ACKNOWLEDGE THE OBVIOUS FROM THE LATEST 11-3.9 MICRON SATELLITE IMAGERY AND BOOST SKY COVER THIS MORNING TO 100 PERCENT FOR ESSENTIALLY THE ENTIRE CWA. AS HAS BEEN FAIRLY WELL CAPTURED BY VARIOUS MODEL LOW-LEVEL RH FIELDS AND ALSO THE LOW CLOUD COVER GUIDANCE FROM THE 09Z HRRR...BLANKET OF LOW STRATUS HAS RAPIDLY OVERTAKEN ALL AREAS OVER THE PAST FEW HOURS. PLENTY OF UNCERTAINTY REMAINS ON ITS ULTIMATE FATE...BUT WILL CONTINUE BANKING ON SOME DEGREE OF AFTERNOON EROSION...LIKELY IN SOME WEST- TO-EAST FASHION. JUST IN CASE THESE LOW CLOUDS HANG FIRMER THAN THOUGHT...WHICH IS VERY POSSIBLE BASED ON WHAT HAPPENED DURING A STRETCH OF DAYS A FEW WEEKS AGO...NUDGED DOWN HIGH TEMPS 1 DEGREE ACROSS THE BOARD. MAYBE THIS WILL ULTIMATELY PROVE TO BE A MINOR BUT INCORRECT MOVE...BUT WHEN IT COMES TO COLD SEASON STRATUS...DOWNWARD IS USUALLY THE DIRECTION TO GO AND THERE IS INCREASING SUPPORT FOR SLIGHTLY COOLER HIGHS IN HOURLY TEMP FIELDS FROM THE 09Z HRRR AS WELL. REITERATING FROM THE EARLIER AFD...WE ARE NOW TRULY AT THE MERCY OF THE LOW STRATUS TODAY AND TO WHAT DEGREE IT DOES/DOESN`T BREAK. PREV DISCUSSION... /ISSUED 459 AM CST MON NOV 5 2012/ SHORT TERM...THROUGH WEDNESDAY NIGHT. DESPITE THE LACK OF MEASURABLE PRECIPITATION CHANCES DURING THE NEXT 72 HOURS...JUST THE FIRST 12 HOURS ALONE PRESENT ANOTHER TRICKY CLOUD COVER/TEMPERATURE FORECAST. IN GENERAL THOUGH...NO MAJOR CHANGE IN EXPECTATIONS FROM PREVIOUS FORECAST...WITH PROGRESSIVELY WARMER TEMPS IN STORE THROUGH WEDNESDAY...AND TODAY STILL VERY MUCH LOOKING LIKE THE CHILLIEST DAY OF THE WORK-WEEK. 09Z CENTRAL PLAINS OBJECTIVE SURFACE ANALYSIS FEATURES A 1015MB LOW ALONG THE KS/MO BORDER...WHILE AN ELONGATED RIDGE AXIS EXTENDS FROM WY TO ND AHEAD OF THE NEXT UPSTREAM NORTHERN ROCKIES LOW. IN BETWEEN THESE FEATURES...A TIGHTENED PRESSURE GRADIENT BEHIND A COLD FRONT IS PROMOTING A NOTICEABLE NORTH-NORTHWEST BREEZE ACROSS MOST ALL OF THE CWA EARLY THIS MORNING...WITH SUSTAINED SPEEDS RANGING 10-20 MPH WITH HIGHER GUSTS. PRE-DAWN TEMPS ACROSS THE CWA ARE GENERALLY IN THE 37-43 RANGE. ALOFT...WATER VAPOR IMAGERY AND SHORT TERM MODEL DATA CLEARLY DEPICT A WELL-DEFINED MID LEVEL SHORTWAVE TROUGH DROPPING SOUTH ACROSS CENTRAL/EASTERN NEB INTO CENTRAL/EASTERN KS AT THIS HOUR...WITH THIS WAVE STILL PROMOTING STEADIER LIGHT RAIN FROM THE MO RIVER EASTWARD INTO IA/MO ON THE EAST SIDE OF A STOUT 110+KT 300MB JET STREAK NOSING SOUTHWARD ACROSS THE AREA. MEANWHILE...ISOLATED/SCATTERED LIGHT SHOWERS THAT AFFECTED PARTS OF MAINLY THE EASTERN CWA EARLIER TONIGHT HAVE SINCE PUSHED OFF EAST OF THE AREA...LIKELY LEAVING NO MORE THAN A FEW HUNDREDTHS OF AN INCH IN THEIR WAKE. AS THE NIGHT HAS WORN ON...THIS LIGHT RAIN AND ASSOCIATED MID LEVEL CLOUDS HAVE SINCE BEEN REPLACED BY A RATHER SOLID BLANKET OF LOW STRATUS AVERAGING UNDER 2000 FT...WHICH HAS ALREADY OVERTAKEN ROUGHLY THE NORTHEAST 2/3 OF THE CWA...AND IS QUICKLY ADVANCING INTO SOUTHWEST COUNTIES AS WELL. TODAY...CLOUD COVER/TEMPS ARE CLEARLY THE BIGGEST ISSUE. PRECIPITATION-WISE...OPTED TO OMIT ALL MENTION THROUGH THE 6AM-6PM DAYTIME PERIOD...ALTHOUGH SUPPOSE ITS NOT COMPLETELY OUT OF THE QUESTION THAT SOME LIGHT DRIZZLE MIGHT YET MATERIALIZE BETWEEN NOW AND MID-MORNING ESPECIALLY IN NORTHEAST COUNTIES. HOWEVER...NAM SOUNDINGS LEAVE A BIT TO BE DESIRED IN TERMS OF LOW LEVEL SATURATION DEPTH FOR DRIZZLE PRODUCTION...AND THUS DO NOT PLAN ON INSERTING ANY MENTION UNLESS GROUND TRUTH REPORTS PROVE IT NECESSARY. TEMP-WISE...MUCH LIKE SOME FORGETTABLE DAYS A FEW WEEKS AGO...WE ARE TRULY AT THE MERCY OF THE LOW STRATUS DECK...AND HOW QUICKLY IT TRIES TO SCATTER OUT OR ADVECT OUT OF THE AREA. AT LEAST FOR THE MORNING HOURS...HAVE FAIRLY HIGH CONFIDENCE THAT MOST IF NOT ALL OF THE CWA IS GOING TO BE QUITE SOCKED IN OVERCAST...AND ALTHOUGH RAISED SKY COVER QUITE A BIT DID PROBABLY NOT GO HIGH ENOUGH IN SOUTHWEST AREAS. BASED ON LOW LEVEL RH PROGS FROM MODELS SUCH AS THE 06Z NAM AND 05Z HRRR WE SHOULD...AT LEAST IN THEORY...SEE SOME KIND OF WEST-TO-EAST PARTIAL CLEARING TREND AS THE AFTERNOON WEARS ON...ALTHOUGH EVEN AREAS THAT LOSE THE LOW CLOUDS SHOULD STILL FARE NO BETTER THAN PARTLY CLOUDY SKIES DUE TO INCOMING HIGH CIRRUS FROM THE NORTHWEST. EASTERN COUNTIES...ESPECIALLY ALONG HWY 81...SHOULD BE LAST TO SEE THE BREAKUP OF THE LOW STRATUS...AND MAY STRUGGLE TO SEE MUCH SUN AT ALL TODAY. ALL THIS BEING SAID...THERE IS CERTAINLY POTENTIAL FOR MISSING HIGHS BY 5+ DEGREES IF CLOUD EXPECTATION DON/T PAN OUT...BUT FOR NOW MADE ONLY MINOR TWEAKS TO PREVIOUS FORECAST...AIMING FOR A RANGE FROM UPPER 40S EAST TO MID 50S SOUTHWEST. ALTHOUGH THIS MORNING WILL REMAIN LEGITIMATELY BREEZY IN THE WAKE OF THE COLD FRONT...ARGUABLY THE BIGGEST CHANGE MADE TO PREVIOUS FORECAST WAS TO DECREASE AFTERNOON WIND SPEEDS AT LEAST 5-7 MPH...WITH SUSTAINED NORTHERLY SPEEDS DECREASING TO AROUND 10 MPH OR LESS BY THE MID-LATE AFTERNOON HOURS. FOR THE 6PM-6AM TONIGHT PERIOD...CONTINUED TO LEAVE ALL PRECIP MENTION OUT...BUT ESPECIALLY NORTHEASTERN COUNTIES COULD END UP IN RELATIVELY CLOSE PROXIMITY TO ANOTHER ROUND OF SPRINKLES/LIGHT RAIN...AND THIS IS SOMETHING THAT BEARS WATCHING BY THE NEXT FEW SHIFTS. IN SHORT...THE NEXT IN A SERIES OF NORTHWEST FLOW SHORTWAVES AND AN ASSOCIATED UPPER LEVEL JET STREAK WILL RIDE DOWN ACROSS THE DAKOTAS INTO IA/NORTHEAST NEB AS THE NIGHT WEARS ON...PROMOTING LEGITIMATE LIGHT RAIN CHANCES ALONG ITS TRACK. AT THIS TIME...IT APPEARS THE CWA WILL RESIDE TOO FAR SOUTHWEST TO REALIZE ANY OF THIS PRECIPITATION GIVEN THE PRESENCE OF PLENTY OF DRY AIR BELOW 700MB PER NAM SOUNDINGS...BUT AGAIN WOULD NOT BE SHOCKED TO SEE A FEW SPRINKLES TRY TO SKIRT NORTHERN AREAS. AT THE SURFACE...THIS MID LEVEL WAVE WILL DRIVE ANOTHER WEAK COLD FRONT INTO THE CWA MAINLY AFTER MIDNIGHT...SWITCHING BREEZES FROM SOUTHERLY TO WEST-NORTHWEST IN ITS WAKE. ALTHOUGH NOT OFFICIALLY REFLECTED IN CURRENT GRIDS...WE COULD SEE STEADY OR EVEN RISING TEMPS LATE TONIGHT BEHIND THIS FRONT AS MIXING PICKS UP...BUT FOR NOW HAVE RETAINED A TRADITIONAL DIURNAL CURVE BUT DID RAISE LOWS A FEW DEGREES MOST AREAS...WITH MOST ALL AREAS BOTTOMING OUT SOMEWHERE IN THE 34-38 RANGE. FOR TUESDAY...ALTHOUGH THERE WILL UNDOUBTEDLY BE SOME DEGREE OF PASSING MID-HIGH CLOUDS...THERE SHOULD NOT BE THE LOW STRATUS ISSUES WE ARE STARTING OUT WITH TODAY...AND OVERALL THINK IT SHOULD BE A MOSTLY SUNNY/PARTLY CLOUD DAY. ANOTHER FAIRLY BREEZY DAY IS IN STORE IN THE WAKE OF THE MID LEVEL WAVE HEADING SOUTHEAST ACROSS IA/MO...WITH SUSTAINED NORTH-NORTHWEST BREEZES AGAIN 15-20 MPH WITH HIGHER GUSTS. DESPITE THESE NORTH WINDS...DECENT MIXING AND SUNSHINE SHOULD GIVE TEMPS A NOTICEABLE BOOST OVER THOSE OF TODAY...AND RAISED HIGHS 1-2 DEGREES MOST AREAS PER MULTI-MODEL CONSENSUS...RANGING FROM UPPER 50S NORTHEAST...LOW 60S TRI-CITIES AND UPPER 60S SOUTHWEST. RELATIVE HUMIDITY VALUES ARE NOW FORECAST INTO THE UPPER 20S DURING THE AFTERNOON MAINLY NORTH OF I-80...BUT SHOULD HOLD SAFELY ABOVE CRITICAL FIRE WEATHER TERRITORY. TUESDAY NIGHT...KEPT POPS ZEROED OUT...AS BROAD RIDGING ALOFT BUILDS A BIT MORE SO OVER THE CENTRAL PLAINS...WHILE AT THE SURFACE...A RIDGE AXIS PASSES THROUGH THE CWA DURING THE NIGHT PROMOTING GENERALLY LIGHT/VARIABLE BREEZES. ASSUMING CLOUDS ARE FAIRLY MINIMAL AS EXPECTED...THIS SHOULD ALLOW TEMPS TO DROP OFF RATHER EFFICIENTLY AND BASED ON MET/MAV GUIDANCE BLEND LOWERED LOWS 1-5 DEGREES ACROSS THE AREA...NOW AIMING FOR MID-UPPER 20S NORTHEAST TO LOW 30S SOUTHWEST. WEDNESDAY...WE CONTINUE TO SEE ESSENTIALLY ZERO RISK OF PRECIP...AS THE HEART OF THE MID-UPPER RIDGE AXIS SLIDES OVER THE CENTRAL PLAINS...BETWEEN A DEEP EASTERN CONUS TROUGH AND THE NEXT UPSTREAM SHORTWAVE OFF THE PACIFIC NORTHWEST COAST. AT THE SURFACE...SOUTHERLY BREEZES WILL PICK UP A BIT BEHIND THE DEPARTING RIDGE AXIS AND IN RESPONSE TO A MODEST HIGH PLAINS LEE TROUGH...AND NUDGED UP SUSTAINED SPEEDS TO AT LEAST 15 MPH DURING THE AFTERNOON. THESE SOUTH BREEZES SHOULD GIVE TEMPS ANOTHER UPWARD BOOST VERSUS THE PREVIOUS DAY. ALTHOUGH PLAYED IT SOMEWHAT CONSERVATIVE AND STAYED AT LEAST 2-4 DEGREES COOLER THAN THE RAW NAM SOLUTION...DID INCREASE PREVIOUS HIGHS GENERALLY 2 DEGREES NOW AIMING FOR A RANGE FROM LOW 60S EAST TO UPPER 60S/LOW 70S WEST. WEDNESDAY NIGHT...FLOW TRANSITIONS TO QUASI-ZONAL OR EVEN SLIGHTLY SOUTHWESTERLY AS THE CENTER OF THE MID-UPPER RIDGE AXIS SLIDES EAST. WITH THE EXPECTATION OF A LEAST LIGHT BUT STEADY SOUTHERLY BREEZES IN MOST AREAS...AM CALLING FOR A BIT WARMER NIGHT THAN TUESDAY NIGHT...AND KEPT LOWS CLOSE TO PREVIOUS FORECAST WITH MOST AREAS HOLDING UP IN THE 37-41 RANGE. LONG TERM...THURSDAY THROUGH SUNDAY. MAIN CHALLENGES INCLUDE PRECIPITATION CHANCES AND TYPE ALONG WITH TEMPERATURES. UPPER PATTERN WILL BE IN THE PROCESS OF AMPLIFICATION FOR THE LONG TERM AS A MAJOR PATTERN SHIFT OCCURS. MODELS ARE IN GOOD AGREEMENT WITH THIS PATTERN SHIFT...BUT DO HAVE SOME MINOR DIFFERENCES. WE BEGIN THURSDAY WITH A DEEPENING EASTERN PACIFIC TROUGH AND PLAINS RIDGE. THIS PLACES US IN A VERY MILD REGIME TO BEGIN THE LONG TERM. THESE FEATURES WILL TRANSLATE EAST OVER TIME AND BY SATURDAY...THE ROBUST DIGGING LONGWAVE TROUGH WILL BE PROMINENT OVER THE INTERMOUNTAIN WEST. SATURDAY COULD TURN OUT TO BE QUITE WARM AHEAD OF THE ASSOCIATED COLD FRONT FROM THE TROUGH THAT IS EXPECTED TO ARRIVE BY SATURDAY NIGHT. THEREFORE I INCREASED HIGH TEMPERATURES ON SATURDAY COMPARED TO ALLBLEND INITIALIZATION. THERE COULD BE SOME SHOWER AND EVEN THUNDERSTORM ACTIVITY IN THE SOUTHEASTERN CWA WHERE MUCAPES WOULD SUPPORT THIS...BUT IT APPEARS FOR NOW THAT MOST OF ANY PRECIPITATION SHOULD FALL SATURDAY NIGHT ALONG AND BEHIND THE COLD FRONT. BY THE TIME WE GET COLD ENOUGH FOR SNOW...QPF SHOULD BE LIMITED...SO NOT LOOKING FOR MUCH ACCUMULATION. THE GFS SWINGS A CLOSED LOW AT 700 MB OVER THE CWA FOR SATURDAY NIGHT WHICH COULD MEAN MORE SNOW...BUT I AM NOT BUYING IN TO THIS AT THIS TIME. I INCREASED WIND SPEEDS SIGNIFICANTLY ON SATURDAY NIGHT AND SUNDAY AS STRONG COLD AIR ADVECTION IS ANTICIPATED FOR SATURDAY NIGHT AND SUNDAY BEHIND THE LONGWAVE TROUGH MOVING EAST. THE TEMPERATURE DROP WILL LIKELY BE TREMENDOUS BETWEEN SATURDAY AND SUNDAY AND I HAVE LOWERED TEMPERATURES FROM ALLBLEND INITIALIZATION FOR SUNDAY. IF CLOUDS STICK AROUND FOR A SIGNIFICANT PORTION OF THE DAY ON SUNDAY...WE VERY WELL MAY STRUGGLE TO GET OUT OF THE 20S...AND COUPLED WITH A STRONG NORTHWEST WIND...THIS COULD BE QUITE AN UNCOMFORTABLY COLD DAY...EVEN FOR NOVEMBER STANDARDS. && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
332 PM EST MON NOV 5 2012 .SYNOPSIS... SURFACE HIGH PRESSURE LOCATED OVER THE NORTHERN GREAT LAKES WILL SLOWLY MOVE TOWARD THE NORTH COUNTRY BY TUESDAY. HOWEVER...A COLD NORTHWEST FLOW AND LEFTOVER MOISTURE WILL CONTINUE TO PRODUCE CLOUDS WITH SCATTERED SNOW SHOWERS THROUGH TONIGHT. SOME BREAKS IN THE OVERCAST ARE ANTICIPATED ON TUESDAY INTO WEDNESDAY...BEFORE A COASTAL SYSTEM INCREASES THE CLOUDS AND THE CHANCES FOR RAIN AND SNOW BY THURSDAY. && .NEAR TERM /THROUGH TUESDAY/... AS OF 330 PM EST MONDAY...WATER VAPOR SHOWS DEEP CLOSED MID/UPPER LVL CIRCULATION NORTH OF MAINE...WHICH CONTS TO PRODUCE AN ACTIVE NORTHWEST FLW ALOFT WITH ROUNDS OF LIGHT SNOW SHOWERS. MEANWHILE...SFC HIGH PRES LOCATED OVER THE NORTHERN GREAT LAKES IS SLOWLY MOVING TWD THE NORTH COUNTRY...BUT VIS SAT PIC CONTS TO SHOW LOTS OF CLOUDS BENEATH THIS FEATURE. STILL DIFFICULT TO DETERMINE AMOUNT OF CLRING TONIGHT/TUESDAY...AS SOUNDINGS CONT TO SHOW RH BTWN 2000 FT AND 6000 FT...ESPECIALLY THE RAP. WL POPULATE SKY GRIDS USING THE RAP THRU 06Z TONIGHT...WITH CLOUDY SKIES ANTICIPATED. ALSO...WITH NORTHWEST FLW AND WEAK S/W ENERGY...ALONG WITH SOME LAKE INSTABILITY...WL CONT TO MENTION CHC POPS ALONG THE EAST SIDE OF THE CPV AND MTNS OF NORTHERN/CENTRAL VT. ACCUMULATIONS WL BE <1.0"...BUT AS TEMPS DROP BLW FREEZING A FEW SLICK SPOTS ON ROADWAYS WL BE POSSIBLE. TEMPS WL ONCE AGAIN BE HIGHLY DEPEND UPON AMOUNT OF CLRING...BUT THINKING WITH CLOUDS AND SOME CLRING AFT MIDNIGHT...LOWS WL RANGE FROM THE UPPER TEENS SLK/NEK TO M/U20S CPV AND LWR CT RIVER VALLEY. ON TUESDAY...MID/UPPER LVL FLW SLOWLY TURNS TO THE SOUTH AND STRONG SUBSIDENCE ALONG WITH A DEEP DRY LAYER MOVES FROM SOUTH TO NORTH ACRS OUR CWA. VIS SATL PICS ACTUAL SHOW THE CLEARING ACRS THE MID ATLANTIC STATES/OHIO VALLEY...SO THINK WE WL SEE SOME SUN. SOUNDINGS SHOW LOTS OF DRY AIR...WITH JUST A LITTLE RH AROUND 3000 FT. WL INCREASE THE AMOUNT OF SUNSHINE AND KEEP SOME CLOUDS ACRS THE MTNS. PROGGED 85H TEMPS BTWN -8C AND -10C...ALONG WITH 925MB NEAR -3C...SUPPORT HIGHS IN THE U20S MTNS TO U30S WARMER VALLEYS...A COUPLE DEGREES WARMER THAN TODAY...DUE TO MORE SUN. && .SHORT TERM /TUESDAY NIGHT THROUGH WEDNESDAY NIGHT/... AS OF 330 PM EDT MONDAY...MID/UPPER LVL RIDGE AND ASSOCIATED SFC HIGH PRES OVERHEAD SHOULD RESULT IN MAINLY CLR SKIES ON TUES NIGHT INTO WEDS. TEMPS WITH CLR SKIES AND LIGHT WINDS SHOULD DROP INTO THE LOWER TEENS SLK/NEK TO UPPER TEENS/LOWER 20S ELSEWHERE. THIS WL BE THE COLDEST NIGHT OF THE SEASON. WEDS...RIDGE BREAKS DOWN AND UPPER LVL MOISTURE WL ADVECT FROM SOUTH TO NORTH ACRS OUR CWA...WITH CLOUDS LOWERING/THICKENING AFT 18Z. WEDS NIGHT...SOUTHERN STREAM ENERGY EJECTING ACRS THE SE CONUS WL INTERACT WITH ADDITIONAL NORTHERN STREAM ENERGY DIGGING ACRS THE NORTHERN PLAINS. THIS WL HELP IN THE DEVELOPMENT OF SFC LOW PRES NEAR CAPE HATTERAS ON WEDS....WITH A SLOW TRACK TO THE NORTH ALONG THE COAST ON WEDS NIGHT. GFS/ECMWF AND NAM SHOW A CLOSED 5H/7H CIRCULATION DEVELOPING BY 00Z THURS OFF THE CAROLINA COAST...WITH SFC LOW PRES JUST SOUTH OF LONG ISLAND BY 12Z THURS. GIVEN...GOOD RIBBON OF 850 TO 500MB RH LIFTING ACRS OUR CWA...ALONG WITH A BAND OF FAVORABLE FG FORCING...WL INCREASE POPS TO CAT SOUTHERN VT ZNS TO CHC SLV ON WEDS NIGHT. THERMAL PROFILES SHOW INITIAL BL TEMPS WL BE WARM ENOUGH FOR RAIN...BUT AS EVAPORATIONAL COOLING OCCURS THE COLUMN SHOULD QUICKLY COOL ENOUGH TO SUPPORT SNOW. HOWEVER...AS EASTERLY WINDS DEVELOP AROUND THE CYCLONIC CIRCULATION...A WARM LAYER BTWN 875MB AND 800MB DEVELOPS WITH TEMPS BTWN 3-5C...SUPPORTING A POTENTIAL MIX. DIFFICULT TO DETERMINE SNOW ACCUMULATIONS ATTM...AS BEST MOISTURE/HIGHEST QPF IS EASTERN/CENTRAL CWA...ALONG WITH THE WARMEST TEMPS...AND WHERE THERMAL PROFILE IS COLDEST ENOUGH FOR ALL SNOW...QPF IS LIGHT. THINKING ADVISORY TYPE EVENT AT MOST AT THIS TIME...BUT ANY SHIFT IN THE TRACK...WL HAVE SIGNIFICANT IMPACTS ON QPF PLACEMENT AND SNOWFALL AMOUNTS. && .LONG TERM /THURSDAY THROUGH MONDAY/... AS OF 323 PM EST MONDAY...PROBABILITY REMAINS HIGH THAT WE WILL FEEL EFFECTS OF COASTAL LOW THURSDAY INTO THURSDAY NIGHT...BUT THE DIFFICULTY LIES IN DETERMINING DETAILS SUCH AS PTYPE AND QPF. BY 12Z THURSDAY..SURFACE LOW EXPECTED TO BE LOCATED SOUTH OF LONG ISLAND...FULLY CAPTURED BY UPPER LOW AT THIS TIME. BEST FGEN WILL BE OCCURRING THROUGH ABOUT 18Z...AFTER WHICH TIME PRECIPITATION BECOMES MORE SHOWERY AND LIGHTER. MAX TEMPS THURSDAY EXPECTED TO BE IN THE MID 30S TO AROUND 40. TEMPS MARGINAL UP THROUGH ABOUT 850 MB. STILL LOOKING AT A MAINLY COLD RAIN OR RAIN/SNOW MIX IN THE VALLEYS AND SNOW OR MIXED PCPN OVER HIGHER TERRAIN WHERE SOME ACCUMULATIONS CAN BE EXPECTED. SOUNDINGS ALSO SUGGEST A PERIOD OF SLEET IS POSSIBLE...ESPECIALLY FROM CHAMPLAIN VALLEY EAST. PRECIPITATION THEN TAPERS OFF THURSDAY NIGHT AS THE VERTICALLY STACKED LOW BEGINS TO MOVE SLOWLY TOWARDS THE EAST-NORTHEAST... STAYING JUST SOUTH OF NEW ENGLAND. TOTAL QPF EXPECTED TO VARY FROM LESS THAN .25 INCHES IN THE SAINT LAWRENCE VALLEY TO AROUND .75 INCHES ACROSS OTHER PORTIONS OF FORECAST AREA. SYSTEM THEN EXITS TO THE EAST ON FRIDAY WHILE HIGH PRESSURE BOTH AT SURFACE AND ALOFT BUILDS EAST FROM THE GREAT LAKES. EXPECT DRY CONDITIONS WITH SOME CLEARING...WITH TEMPERATURES RETURNING TO NEAR NORMAL. HIGH PRESSURE MOVES ACROSS THE NORTH COUNTRY ON SATURDAY AND THEN PASSES OFF NEW ENGLAND COAST ON SUNDAY. AMOUNT OF SUNSHINE IN QUESTION THOUGH AS WE WILL LIKELY SEE A FAIR AMOUNT OF CLOUDS ASSOCIATED WITH WARM AIR ADVECTION. IT WILL REMAIN MAINLY DRY MONDAY WITH WARMING TREND CONTINUING IN ADVANCE OF NEXT FRONTAL SYSTEM. MAX TEMPS WILL BE NEAR NORMAL ON SATURDAY...THEN CLIMB TO WELL ABOVE NORMAL LEVELS BY MONDAY. && .AVIATION /21Z MONDAY THROUGH SATURDAY/... THROUGH 18Z TUESDAY...SHORTWAVE TROUGH COMBINED WITH STEEP LOW LEVEL LAPSE RATES DUE COLD POOL ALOFT WILL RESULT IN CONTINUATION OF MAINLY CLOUDY SKIES ACROSS THE FORECAST AREA THIS AFTERNOON ALONG WITH SCATTERED SNOW SHOWERS. CONDITIONS MAINLY VFR...EXCEPT CIGS/VSBYS LOWERING TO MVFR AT TIMES IN SCATTERED SNOW SHOWERS. BEST CHANCE FOR SNOW SHOWERS WILL BE SLK/BTV/MPV. SKIES REMAIN MOSTLY CLOUDY TONIGHT WITH VFR/MVFR CIGS FOLLOWED BY DECREASING CLOUDS TUESDAY AS HIGH PRESSURE BUILDS INTO THE REGION. WINDS WILL BE MAINLY NORTHWEST 8-13 KNOTS THIS AFTERNOON...THEN BECOMING LIGHT AND VARIABLE TONIGHT/TUESDAY. OUTLOOK 18Z TUESDAY THROUGH SATURDAY... 18Z TUESDAY THROUGH 00Z THURSDAY...MAINLY VFR AS A RIDGE OF HIGH PRESSURE MOVES ACROSS THE AREA. 00Z THURSDAY THROUGH 12Z FRIDAY...DETERIORATING TO MVFR/IFR IN MIXED PRECIPITATION WEDNESDAY NIGHT THROUGH THURSDAY NIGHT DUE TO COASTAL LOW PRESSURE SYSTEM. 12Z FRIDAY THROUGH 00Z SUNDAY...BECOMING VFR ON FRIDAY AS LOW DEPARTS FRIDAY AND HIGH PRESSURE BUILDS INTO THE REGION ON SATURDAY. && .BTV WATCHES/WARNINGS/ADVISORIES... VT...NONE. NY...NONE. && $$ SYNOPSIS...TABER NEAR TERM...TABER SHORT TERM...TABER LONG TERM...RJS AVIATION...RJS