Forecast Discussions mentioning any of "HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 11/06/13


AREA FORECAST DISCUSSION
NWS TUCSON AZ
915 AM MST MON NOV 4 2013 .SYNOPSIS...A WEATHER SYSTEM WILL BRING GUSTY WINDS THIS AFTERNOON WITH SHOWERS DEVELOPING THIS EVENING AND OVERNIGHT. COOLER AIR WILL FOLLOW ON TUESDAY AND WEDNESDAY. DRY CONDITIONS AND COLD MORNINGS WITH WARMER DAYTIME TEMPERATURES CAN BE ANTICIPATED LATE IN THE WEEK AS HIGH PRESSURE BUILDS OVER THE REGION. && .DISCUSSION...THE WEATHER SYSTEM FORECAST TO IMPACT THE AREA LATER TODAY WAS STILL ON TRACK THIS MORNING. EXPECTING CLOUDS TO SPREAD INTO THE AREA THIS AFTERNOON WITH SHOWERS AND POSSIBLY A FEW THUNDERSTORMS DEVELOPING THIS EVENING AND MORE SO TONIGHT. AS THE SYSTEM APPROACHES...WIND SPEEDS WILL INCREASE BUT REMAIN BELOW ANY ADVISORY CRITERIA. NOT EXPECTING MUCH OF A THREAT FOR WIDESPREAD BLOWING DUST...BUT LOCALIZED REDUCED VISIBILITY IN DUST PRONE AREAS WILL BE A POSSIBILITY MAINLY IN PINAL COUNTY. THAT SAID...THE CURRENT FORECAST LOOKED IN GOOD SHAPE SO NO UPDATES EXPECTED THIS MORNING. PLEASE REFER TO THE PREVIOUS DISCUSSION FOR MORE DETAILS. && .AVIATION...A FEW CLOUDS THROUGH 04/21Z WITH SFC WINDS BELOW 8 KTS. CLOUDS INCREASING AFTER 04/21Z WITH SCT-BKN CLOUDS 6-10K FT AGL AND SCT -SHRA/-TSRA PSBL AFT 05/00Z AS A WEATHER SYSTEM MOVES IN. SWLY SFC WINDS 10-20 KTS WITH HIGHER GUSTS EXPECTED TO DEVELOP AFT 04/19Z...DIMINISHING AFTER 05/03Z FOR MOST LOCATIONS. AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS. && .FIRE WEATHER...A WEATHER SYSTEM DIGGING INTO SOUTHERN CALIFORNIA WILL KICK UP A 15-20 MPH SOUTHWEST BREEZE THIS AFTERNOON AS IT PUSHES TOWARD SOUTHEAST ARIZONA...WITH A THREAT OF SHOWERS AND ISOLATED THUNDERSTORMS DEVELOPING THIS EVENING AND MORE SO TONIGHT. THE BREEZE WILL DIE OFF IN MOST LOCATIONS AFTER SUNSET WITH THE THREAT OF SHOWERS AND POSSIBLE THUNDERSTORMS INCREASING DURING THE NIGHTTIME HOURS. COOLER TEMPERATURES WILL THEN FOLLOW THE PASSAGE OF THIS SYSTEM TUESDAY INTO WEDNESDAY. TEMPERATURES WILL RETURN TO NORMAL OR ABOVE NORMAL LEVELS LATER IN THE WEEK AS A RIDGE OF HIGH PRESSURE MOVES OVER THE REGION. && .PREV DISCUSSION...CLEAR WITH SOME RESIDUAL MAINLY BOUNDARY LAYER MOISTURE HANGING ON ACROSS SE AZ THIS MORNING. SURFACE DEWPTS STILL UP IN THE 30S AND 40S EVEN AS SATELLITE PRECIPITABLE WATER ESTIMATES FALL FROM THE .65 RANGE YESTERDAY AFTERNOON TO ABOUT .45 TO .5 AS OF 2 AM. THIS SLOW DRYING TREND WILL LIKELY CONTINUE THIS MORNING BEFORE THE INCREASING SOUTHERLY FLOW AHEAD OF THE APPROACHING SYSTEM STARTS TO DRAW MOISTURE BACK UP THIS AFTERNOON. LATEST HRRR DEVELOPS SOUTHERLY SURFACE STREAMLINES YET THIS MORNING...AND BY 21Z SHOWS A RATHER BRISK FLOW AND LONG FETCH FROM THE SOUTHWEST. TROUGH DIGGING INTO THE REGION AS DEEP AS SOUTHERN CALIFORNIA. NAMDNG5 AND ECMWF SHOW A NICE STRONG LOWER LATITUDE IMPULSE ENHANCING THE BASE OF THE TROUGH IMMEDIATELY UPSTREAM OF OUR AREA...WITH THIS FEATURE PUSHING ACROSS SOUTHERN AND CENTRAL ARIZONA THIS EVENING. STRONG UPSLOPE AHEAD OF THE PVA LOBE MAY GET A FEW SHOWERS GOING LATER THIS AFTERNOON NEAR THE MOUNTAINS...BUT BEST MOISTURE AND DYNAMICS COUPLET PHASE THROUGH SE AZ BETWEEN 02Z-12Z WITH A SECONDARY IMPULSE KEEPING MORE LIMITED ACTIVITY WELL INTO TUESDAY. THIS SHOULD BE A COLDER AND MORE EFFICIENT SYSTEM WITH SNOW LEVELS FALLING AS LOW AS 7500 TO 8500 FEET AND 1 TO 4 INCHES OF SNOW EXPECTED ABOVE 8000 FEET. VALLEY STORM TOTAL QPF ON THE ORDER OF .05 TO .35 WITH ISOLATED HIGHER SPOTS MAINLY FROM TUCSON EASTWARD. TRAILING AND WEAKENED FRONTAL BOUNDARY SAGS INTO OUR PART OF THE STATE TUESDAY AFTERNOON WITH MUCH COOLER AIRMASS WEDNESDAY AND THURSDAY MORNINGS. ANOTHER ROUND OF FREEZING TEMPERATURES ABOVE 3500-4000 FEET AND FAVORED COLD VALLEY LOCATIONS (PORTIONS OF COCHISE...SANTA CRUZ AND GRAHAM COUNTIES) WITH LIMITED BRIEF HARD FREEZE POTENTIAL IN COLDEST SPOTS. RIDGE PHASES OVERHEAD FOR A RAPID WARMING RESPONSE LATE IN THE WEEK BUT WITH CONTINUED STORM ACTIVITY IN WESTERN REGION THROUGH MUCH HIGHER LATITUDES WE SHOULD CAP THAT TREND OFF BY THE WEEKEND. BACK TO A FEW DEGREES ABOVE CLIMO BY FRIDAY. && .TWC WATCHES/WARNINGS/ADVISORIES...NONE. && $$ VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON
AREA FORECAST DISCUSSION
NWS TUCSON AZ
245 AM MST MON NOV 4 2013 .SYNOPSIS...A PACIFIC WEATHER SYSTEM WILL BRING GUSTY WINDS THIS AFTERNOON AND THEN SHOWERS TO THE AREA THIS EVENING INTO TUESDAY MORNING. WITH COOLER AIR TUESDAY AND WEDNESDAY...EXPECT DRY CONDITIONS AND COLD MORNINGS FOLLOWED BY A WARMING TREND AS HIGH PRESSURE BUILDS INTO THE AREA LATE IN THE WEEK. && .DISCUSSION...CLEAR WITH SOME RESIDUAL MAINLY BOUNDARY LAYER MOISTURE HANGING ON ACROSS SE AZ THIS MORNING. SURFACE DEWPTS STILL UP IN THE 30S AND 40S EVEN AS SATELLITE PRECIPITABLE WATER ESTIMATES FALL FROM THE .65 RANGE YESTERDAY AFTERNOON TO ABOUT .45 TO .5 AS OF 2 AM. THIS SLOW DRYING TREND WILL LIKELY CONTINUE THIS MORNING BEFORE THE INCREASING SOUTHERLY FLOW AHEAD OF THE APPROACHING SYSTEM STARTS TO DRAW MOISTURE BACK UP THIS AFTERNOON. LATEST HRRR DEVELOPS SOUTHERLY SURFACE STREAMLINES BY 16Z...AND BY 21Z SHOWS A RATHER BRISK FLOW AND LONG FETCH FROM THE SOUTHWEST. TROUGH DIGGING INTO THE REGION AS DEEP AS SOUTHERN CALIFORNIA BY 12Z. NAMDNG5 AND ECMWF SHOW A NICE STRONG LOWER LATITUDE IMPULSE ENHANCING THE BASE OF THE TROUGH IMMEDIATELY UPSTREAM OF OUR AREA...WITH THIS FEATURE PUSHING ACROSS SOUTHERN AND CENTRAL ARIZONA THIS EVENING. STRONG UPSLOPE AHEAD OF THE PVA LOBE MAY GET A FEW SHOWERS GOING LATER THIS AFTERNOON NEAR THE MOUNTAINS...BUT BEST MOISTURE AND DYNAMICS COUPLET PHASE THROUGH SE AZ BETWEEN 02Z-12Z WITH A SECONDARY IMPULSE KEEPING MORE LIMITED ACTIVITY WELL INTO TUESDAY. THIS SHOULD BE A COLDER AND MORE EFFICIENT SYSTEM WITH SNOW LEVELS FALLING AS LOW AS 7500 TO 8500 FEET AND 1 TO 4 INCHES OF SNOW EXPECTED ABOVE 8000 FEET. VALLEY STORM TOTAL QPF ON THE ORDER OF .05 TO .35 WITH ISOLATED HIGHER SPOTS MAINLY FROM TUCSON EASTWARD. TRAILING AND WEAKENED FRONTAL BOUNDARY SAGS INTO OUR PART OF THE STATE TUESDAY AFTERNOON WITH MUCH COOLER AIRMASS WEDNESDAY AND THURSDAY MORNINGS. ANOTHER ROUND OF FREEZING TEMPERATURES ABOVE 3500-4000 FEET AND FAVORED COLD VALLEY LOCATIONS (PORTIONS OF COCHISE...SANTA CRUZ AND GRAHAM COUNTIES) WITH LIMITED BRIEF HARD FREEZE POTENTIAL IN COLDEST SPOTS. RIDGE PHASES OVERHEAD FOR A RAPID WARMING RESPONSE LATE IN THE WEEK BUT WITH CONTINUED STORM ACTIVITY IN WESTERN REGION THROUGH MUCH HIGHER LATITUDES WE SHOULD CAP THAT TREND OFF BY THE WEEKEND. BACK TO A FEW DEGREES ABOVE CLIMO BY FRIDAY. && .AVIATION...VALID THROUGH 05/09Z. FEW CIRRUS CLOUDS THROUGH 04/17Z WITH SFC WINDS BELOW 8 KTS. CLOUDS INCREASING AFTER 04/18Z WITH SCT-BKN CLOUDS 6-10K FT AGL AND SCT -SHRA/-TSRA PSBL AFT 04/23Z AS A WEATHER SYSTEM MOVES IN. SWLY SFC WINDS 10-20 KTS WITH HIGHER GUSTS EXPECTED TO DEVELOP AFT 04/18Z...DIMINISHING AFTER 05/03Z FOR MOST LOCATIONS. AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS. && .FIRE WEATHER...A WEATHER SYSTEM DIGGING INTO SOUTHERN CALIFORNIA WILL KICK UP A 15-20 MPH SOUTHWEST BREEZE THIS AFTERNOON AS IT PUSHES TOWARD SOUTHEAST ARIZONA...WITH A THREAT OF SHOWERS AND ISOLATED THUNDERSTORMS DEVELOPING BY THIS EVENING. THE BREEZE WILL DIE OFF IN MOST LOCATIONS AFTER SUNSET WITH THE THREAT OF SHOWERS AND POSSIBLE THUNDERSTORMS INCREASING DURING THE NIGHTTIME HOURS. COOLER TEMPERATURES WILL THEN FOLLOW THE PASSAGE OF THIS SYSTEM TUESDAY INTO WEDNESDAY. TEMPERATURES WILL RETURN TO NORMAL OR ABOVE NORMAL LEVELS LATER IN THE WEEK AS A RIDGE OF HIGH PRESSURE MOVES OVER THE REGION. && .TWC WATCHES/WARNINGS/ADVISORIES...NONE. && $$ VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON MEYER/MEADOWS/CERNIGLIA
AREA FORECAST DISCUSSION
NWS PUEBLO CO
310 PM MST MON NOV 4 2013 .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 237 PM MST MON NOV 4 2013 CURRENTLY...WATER VAPOR AND VISIBLE SATELLITE IMAGERY SHOWS PLENTY OF MID LEVEL MOISTURE STREAMING AHEAD OF THE TROUGH DIGGING ACROSS THE GREAT BASIN. MOST OF THE LOW STRATUS THAT RAN ALONG MUCH OF THE SOUTHERN COLORADO I-25 CORRIDOR HAS FINALLY DISSIPATED AS WINDS HAVE TURNED MORE SOUTHERLY THEN SOUTHEASTERLY. TONIGHT AND TUESDAY... THE 18Z NAM12 AND LATEST RAP/HRRR RUNS BEGIN SNOW SHOWERS ACROSS THE SAN JUANS AND EASTERN MOUNTAINS BETWEEN 00Z AND 03Z TONIGHT. WINTER WEATHER ADVISORIES IN THESE AREAS BEGIN AT 00Z AND LOOK TO BE IN GOOD SHAPE AT THIS TIME. THE HEAVIEST SNOWFALL RATES WILL BE DURING THE OVERNIGHT HOURS AS A STRONG VORT MAX/BEST LIFT PUSHES THROUGH THE CWA. THE NAM12 AND RAP CONTINUE TO INDICATE A BAND OF PRECIPITATION WILL DEVELOP FROM THE SAN JUANS NORTHEAST THROUGH PUEBLO COUNTY BETWEEN 06Z AND 09Z. THE LATEST HRRR SHOWS THE BAND SETTING UP IN NORTHWEST EL PASO AND EASTERN TELLER COUNTIES. PREVIOUS MODEL RUNS DID NOT LOOK AS IMPRESSIVE WITH THIS FEATURE. CURRENT SCATTERED POPS LOOK REASONABLE IN THESE AREAS FOR NOW IF 00Z MODEL RUNS CONTINUE TO SHOW THIS FEATURE...POPS WILL NEED TO BE INCREASED. MODELS CONTINUE TO AGREE ON A COLD FRONT PUSHING SOUTHWARD ACROSS EASTERN COLORADO...MOVING THROUGH COS AND PUB BETWEEN 12Z AND 15Z. THIS WILL LOWER 700MB TEMPERATURES FROM +1C TO +3C DOWN TO -7C TO -9C BY TUESDAY EVENING (00Z WED). ANY SHOWERS REMAINING IN THE AREA AFTER THAT TIME WILL CHANGE TO SNOW WITH LITTLE TO NO ACCUMULATION EXPECTED. THE COLD FRONTAL PASSAGE MAY ALSO HAVE AN IMPACT ON THE MORNING COMMUTE OVER MONUMENT HILL IF SNOW SHOWERS DEVELOP. MOST PRECIPITATION ACROSS THE CONTINENTAL DIVIDE AND ACROSS THE EASTERN PLAINS WILL BEGIN TO WIND DOWN AFTER 18Z. HOWEVER...THE 18Z NAM12 AND 12Z EC NOW CONTINUE SNOW SHOWERS OVER THE CENTRAL MOUNTAINS THROUGH AT LEAST 00Z. -PJC .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 237 PM MST MON NOV 4 2013 ...LINGERING SNOW CHANCES ALONG THE EASTERN MOUNTAINS TUESDAY EVENING WITH RAIN/SNOW SHOWERS POSSIBLE SOUTHERN BORDER AREAS... THE 12 AND 18Z RUNS OF THE NAM12 HAVE GRADUALLY COME MORE IN LINE WITH THE GFS AND ECMWF WITH REGARDS TO GENERATING SOME SNOW ALONG THE EASTERN MOUNTAINS TUESDAY EVENING BEFORE ALL COMES TO AN END AFTER MIDNIGHT. RIGHT NOW...IT LOOKS LIKE 1-3 INCHES OF ADDITIONAL SNOW COULD FALL ACROSS THE WETS...WET MOUNTAIN VALLEY...SANGRE DE CRISTOS AND ADJACENT AREAS TUESDAY EVENING IN ADDITION TO WHATEVER FALLS BEFORE THAT. ALSO...THE SOUTHERN BORDER AREAS OF LAS ANIMAS AND BACA COUNTIES COULD SEE A MIXTURE OF RAIN AND SNOW SHOWERS TUESDAY EVENING BEFORE ALL IS DONE...ALTHOUGH MARGINAL TEMPERATURES WILL LIMIT ANY ACCUMULATIONS TO JUST A DUSTING OR LESS. LOOKS DRY FOR ALL OTHER AREAS TUESDAY NIGHT. WEDNESDAY WILL BE BREEZY AND COOL BUT ANY PRECIPITATION SHOULD BE OVER. THEN...THURSDAY THROUGH MONDAY LOOKS DRY...MILD AND BREEZY TO WINDY AT TIMES. FRIDAY LOOKS ESPECIALLY WINDY AS IT APPEARS A FAST MOVING SHORTWAVE WILL CROSS THE CENTRAL AND NORTHERN ROCKIES... BRINGING A STRONG UPPER LEVEL JET ACROSS THE AREA...AND STRONG DOWNSLOPE FLOW. THIS COULD POTENTIALLY BE A DAY OF HIGH WIND WARNINGS AND/OR HIGH FIRE DANGER AND WE WILL CONTINUE TO MONITOR AS THE DAY APPROACHES. THURSDAY...AND SATURDAY THROUGH MONDAY...ALL LOOK BREEZY TO WINDY AT TIMES AS WELL...BUT FRIDAY DEFINITELY LOOKS LIKE THE WINDIEST DAY OF THE BUNCH. LW && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING) ISSUED AT 237 PM MST MON NOV 4 2013 KALS...GUSTY SOUTH-SOUTHWEST WINDS WILL CONTINUE AT THE AIRFIELD UNTIL 02Z TONIGHT. SNOW AND RAIN SHOWERS ARE STILL EXPECTED TO DEVELOP OVER THE SAN JUAN MOUNTAINS EARLY THIS EVENING AND MOVE IN TO THE SAN LUIS VALLEY TONIGHT. THE BEST CHANCE FOR PRECIPITATION AT KALS IS BETWEEN 02-06Z TONIGHT. MVFR CONDITIONS ARE LIKELY WITH ANY SHOWERS THAT PASS OVER THE TERMINAL. CIGS WILL BEGIN TO RISE AFTER 12Z. EXPECT VFR CONDITIONS THROUGHOUT THE DAY WITH GUSTY SOUTHWEST WINDS BETWEEN 20Z AND 00Z. KCOS...BREEZY SOUTH-SOUTHWEST WINDS WILL CONTINUE UNTIL ABOUT 04Z TONIGHT. SNOW SHOWERS ARE STILL EXPECTED TO DEVELOP ACROSS THE MOUNTAINS WEST OF THE TERMINAL AND WILL MOVE EAST DURING THE OVERNIGHT HOURS. THESE SNOW SHOWERS MAY REDUCE CONDITIONS TO MVFR FOR SHORT PERIODS OF TIME. A COLD FRONTAL PASSAGE WILL SHIFT THE WINDS TO THE NORTH AROUND 13Z. GUSTY NORTH WINDS WILL REMAIN OVER THE AIR FIELD UNTIL TUESDAY EVENING. VFR CONDITIONS ARE EXPECTED. KPUB...VFR CONDITIONS ARE EXPECTED THROUGH AT LEAST 06Z TONIGHT. SOME RAIN SHOWERS MAY PASS OVER THE TERMINAL AFTER 06Z WITH BRIEF REDUCTIONS TO MVFR CONDITIONS POSSIBLE. A COLD FRONT WILL MOVE THROUGH THE AIR FIELD BETWEEN 13Z AND 14Z SHIFTING THE WINDS TO THE NORTH. GUSTY NORTH WINDS WILL LAST THROUGHOUT THE DAY WITH GUSTS TO 25 KTS POSSIBLE. VFR CONDITIONS ARE EXPECTED AFTER 18Z TUESDAY. -PJC && .PUB WATCHES/WARNINGS/ADVISORIES... WINTER WEATHER ADVISORY UNTIL 11 AM MST TUESDAY FOR COZ058-060- 066-068. WINTER WEATHER ADVISORY UNTIL 5 PM MST TUESDAY FOR COZ073-075- 080-082. && $$ SHORT TERM...PJC LONG TERM...LW AVIATION...PJC
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
350 PM EST MON NOV 4 2013 .DISCUSSION... ...WINDY WITH DANGEROUS SURF AND MODERATE BEACH EROSION AT THE COAST THROUGH WED MORNING... ...HAZARDOUS MARINE CONDITIONS FOR SMALL CRAFT THROUGH MID WEEK... TONIGHT-TUESDAY...LITTLE CHANGE TO THE OVERALL WX PATTERN AS THE HIGH PRES RIDGE OVER THE ERN CONUS WILL CONTINUE TO INTERACT WITH AN INVERTED TROF NEAR THE WINDWARD PASSAGE TO CREATE A TIGHT PGRAD ACRS THE FL PENINSULA. LATEST RUC13 ANALYSIS INDICATING SOLID 25KT WINDS THRU 5KFT WELL INTO THE ATLC AND UP THE ERN SEABOARD TO THE NC OUTER BANKS. WINDS APPROACHING 30KTS IN AREAS N OF CAPE CANAVERAL AND S OF SEBASTIAN INLET. WILL RETOOL THE FCST TO UPGRADE AND EMPHASIZE OVERALL WIND/HIGH SURF THREAT...PARTICULARLY ALONG THE COAST. THE TIGHT PGRAD WILL MAINTAIN STEADY WINDS OVER THE INTERIOR OVERNIGHT...KEEPING THE AIRMASS WELL MIXED. SFC FRICTION WILL ALLOW WINDS TO DIMINISH OVER THE INTERIOR AFT SUNSET...COASTAL ZONES WILL SEE GUSTY CONDITIONS CONTINUE OVERNIGHT. CONDITIONS WILL ONLY DETERIORATE AFT SUNRISE TUE AS THE RIDGE AXIS PUSHES INTO THE W ATLC...FORCING WINDS TO VEER TO THE E AND SHUNTING ANY WIND/WAVE ENERGY DIRECTLY ONSHORE. MORNING BEACH REPORTS INDICATED LITTLE IN THE WAY OF DUNE EROSION ALONG THE BEACHES N OF SEBASTIAN INLET...BUT SOME MINOR EROSION S OF THE INLET. DATA BUOY009 WAS APPROACHING THE 10FT MARK AS OF MID AFTN WITH NEARSHORE BUOYS APPROACHING 8FT. SEAS LIKELY NEAR 12FT IN THE GULF STREAM. GIVEN THE SIGNIFICANT BEACH EROSION THAT OCCURRED AFTER THE SUSTAINED NRLY WIND EVENTS LAST MONTH...THE FACT THE GULF STREAM PASSES MUCH CLOSER TO THE COAST S OF SEBASTIAN INLET...AND WITH THE HIGHEST ASTRONOMICAL TIDES OF THE YEAR OCCURRING THRU MIDWEEK...HAVE OPTED TO ISSUE A COASTAL FLOOD WATCH FROM INDIAN RIVER TO MARTIN COUNTY EFFECTIVE THRU THE TUE MRNG HIGH TIDE CYCLE. MINIMAL NOCTURNAL WIND DIFFERENTIAL FOR THE COASTAL COUNTIES...LAKE WIND ADVISORIES WILL CONTINUE OVERNIGHT AND WILL BE UPGRADED TO A FULL WIND ADVISORY AFT SUNRISE TUE. NOCTURNAL MINIMUMS OVER THE INTERIOR COUNTIES WILL ALLOW LAKE WIND ADVISORIES TO EXPIRE AFT SUNSET...BUT WILL BE BACK IN EFFECT AFT SUNRISE TUE. DENSE MARINE STRATOCU FIELD WILL CONTINUE TO ADVECT ACRS THE CENTRAL PENINSULA THRU TUE...BUT THE SHARP SUBSIDENCE INVERSION IN THE H90-H70 LYR WILL CONTINUE TO LIMIT VERTICAL MOTION BLO 10KFT. WILL SEE ISOLD -SHRAS DVLP IN LCL CONVERGENCE BANDS...BUT OVERALL COVERAGE WILL BE LOW AND ANY IMPACT MINIMAL. QPF VALUES AOB 0.10" COMBINATION OF OVERNIGHT CLOUD COVER AND WELL MIXED AIR WILL KEEP OVERNIGHT TEMPS WELL ABV AVG...5-10F INTERIOR (M/U60S)...AND 10-15F ALONG THE COAST (L/M70S). THESE SAME WX FEATURES WILL COMBINE TO LIMIT SFC HEATING TUE AFTN...MAX TEMPS IN THE U70S/L80S WILL BE NO MORE THAN 10F OFF THEIR MORNING MINS ALONG THE COAST...10-15F INTERIOR. WED...SURFACE HIGH MOVES INTO THE ATLANTIC WITH THE WINDY ONSHORE DIMINISHING TO THE BREEZY CATEGORY. LOW TOPPED ATLANTIC SHOWERS THROUGH MID WEEK WITH THE BREEZY ONSHORE FLOW. TIME HEIGHT CROSS SECTIONS SHOWING THAT THE STRONG MID LEVEL CAP STILL LIMITING ANY VERTICAL DEVELOPMENT THUS LOW TOPPED SHOWERS COMING OFF THE ATLANTIC FOR ANOTHER DAY. PREVIOUS DISCUSSION THU-SUN... GRADIENT WILL SLACKEN CONSIDERABLY BY THURSDAY AS THE SURFACE HIGH MOVES FURTHER EAST. THE NEXT UPPER LEVEL TROUGH WILL SWING THROUGH THE CENTRAL US DURING THE MIDDLE OF THE WEEK BEFORE IT RUNS INTO THE STRONG UPPER LEVEL RIDGE PARKED ACROSS FLORIDA AND THE GULF. THIS WILL SEND ALL OF ITS ENERGY WELL NORTH ACROSS THE GREAT LAKES/NE US ALONG WITH ITS ASSOCIATED SURFACE LOW. THE STRUNG OUT SURFACE FRONT WILL DRAG INTO THE FL PENINSULA LATE THURSDAY NIGHT/EARLY FRIDAY MORNING WITH VERY LITTLE FANFARE OTHER THAN A RESURGENCE OF NORTHEAST FLOW AS ANOTHER SURFACE HIGH SPRAWLS ACROSS THE SOUTHEAST. DAYTIME HIGHS WILL PEAK WED/THU IN THE MID 80S...4-6 DEGREES ABOVE NORMAL FOR EARLY NOVEMBER. MINOR POST FRONTAL COLD AIR ADVECTION WILL LOWER MAX TEMPS TO THE UPPER 70S/LOWER 80S NORTH/CENTRAL CWA AND LOWER/MID 80S FOR THE SOUTHERN AREAS. MIN TEMPS WILL REMAIN ABOVE NORMAL NEAR THE COAST DUE TO LONG FETCH OF ONSHORE FLOW. FARTHER INLAND...MINS WILL COOL TO MID/UPPER 60S BEHIND THE FRONT FRI-SUN. SURF WILL BEGIN TO SLOWLY SUBSIDE WEDNESDAY...BUT LIKELY TO REMAIN ROUGH...ALONG WITH AN ENHANCED RIP CURRENT RISK...AND CONTINUED BEACH EROSION THROUGH THE DAY. ANOTHER SURGE OF ONSHORE FLOW FRIDAY WILL AGAIN BUILD SEAS AND QUICKLY RETURN COASTAL HAZARD THREATS. && .AVIATION... THRU 05/00Z...ALL SITES FRQT E/NE SFC WND G23-29KTS...PREVAILING CIGS BTWN FL060-070...BRIEF MVFR CIGS/VSBYS IN ISOLD -SHRAS. BTWN 05/00Z-05/15Z...CSTL SITES OCNL E/NE SFC WND G22-25KTS...ALL SITES PREVAILING CIGS BTWN FL050-060 WITH BRIEF MVFR IN ISOLD -SHRAS. AFT 05/15Z...E/NE SFC WND G23-28KTS...BRIEF MVFR CIGS/VSBYS IN ISOLD SHRAS. && .MARINE... TONIGHT-TUESDAY...HAZARDOUS BOATING CONDITIONS AS INTERACTION BTWN THE EAST COAST HIGH PRES RIDGE AND THE INVERTED TROF JUST E OF THE WINDWARD PASSAGE WILL A GENERATE STRONG E/NE BREEZE WITH NEAR GALE CONDITIONS. AFTN WINDS SUSTAINED 22-27KTS WITH GUSTS NEAR 30KTS AT BUOY008/009...SETTLEMENT POINT AND LAKE WORTH...AND THE NEW SMYRNA BEACH ARPT. SEAS 8-10FT NEAR SHORE AND UP TO 12FT OFFSHORE WITH DOMINANT PDS BTWN 7-9SEC. LATEST RUC ANALYSIS SHOWING 0KT WINDS IMPINGING ON THE E FL COAST N OF THE CAPE AND S OF SEBASTIAN INLET. AFT COORD WITH WFO MFL...HAVE DECIDED TO UPGRADE THE SCA TO A GALE WARNING BTWN 05/03Z-05/21Z AS FQNT GUSTS TO GALE FORCE ARE EXPECTED. WED...STRONG EASTERLY WINDS DIMINISH DURING THE DAY AS THE GRADIENT BETWEEN THE HIGH TO THE NORTH AND BROAD AREA OF LOW PRESSURE IN THE CARRIBEAN RELAXES. SEAS SLOWER TO SUBSIDE AS 10 FOOT SEAS OFFSHORE DROP DOWN TO 7 TO 8 FOOT SEAS WED NIGHT. THU-SAT...WINDS VEER FROM THE SOUTHEAST TO VARIABLE AS A WEAK SURFACE TROUGH MOVES OVERHEAD WED NIGHT/EARLY THU TO THE NORTHWEST AND NORTH OVERNIGHT THU. HAZARDOUS CONDITIONS START OVERNIGHT THU AND CONTINUE THROUGH SAT...IF NOT INTO SUN...AS THE WINDS BECOME NORTH TO NORTHEAST AND INCREASE TO 15 TO 20 KNOTS FRI AND HIGHER SAT AS HIGH PRESSURE BUILDS DOWN FROM THE SOUTHEAST UNITED STATES. SEAS FORECAST TO BUILD TO 8 FEET IN THE GULF STREAM BY FRI NIGHT AND 5 FEET NEARSHORE TO 9 FEET IN THE GULF STREAM SAT. && .FIRE WEATHER... TUE...THE STRONG NORTHEASTERLY FLOW WILL WILL ADVECT SUFFICIENT OCEAN MOISTURE ONSHORE TO KEEP MIN RH VALUES ABOVE CRITICAL LEVELS THIS AFTERNOON...THOUGH A FEW FAR INLAND LOCATIONS MAY SEE VALUES DROP BRIEFLY TO 40 PERCENT. THE MAIN CONCERN WILL BE THE WINDY CONDITIONS WITH SUSTAINED 20FT WINDS 15 TO 20 MPH AND GUSTS UP TO 30 MPH. THESE WINDS WILL LEAD TO EXCELLENT DISPERSION VALUES WHICH WILL POSE A CONCERN FOR RAPID FIRE SPREAD. A DECREASE IN WINDS WED AND ESPECIALLY THU WILL REDUCE FIRE CONCERNS SLIGHTLY. RELATIVE HUMIDITY VALUES REMAIN ABOVE 40 PERCENT && .PRELIMINARY POINT TEMPS/POPS... DAB 71 79 68 84 / 20 20 20 10 MCO 69 81 67 86 / 20 20 10 10 MLB 72 80 74 84 / 20 20 20 10 VRB 72 80 73 84 / 20 20 20 10 LEE 66 81 64 85 / 20 20 10 10 SFB 69 81 67 85 / 20 20 10 10 ORL 68 81 66 85 / 20 20 10 10 FPR 72 80 73 85 / 20 20 20 10 && .MLB WATCHES/WARNINGS/ADVISORIES... FL...LAKE WIND ADVISORY UNTIL 7 PM EST THIS EVENING FOR INLAND VOLUSIA-NORTHERN LAKE-OKEECHOBEE-ORANGE-OSCEOLA-SEMINOLE- SOUTHERN LAKE. LAKE WIND ADVISORY UNTIL 7 AM EST TUESDAY FOR COASTAL VOLUSIA- INDIAN RIVER-MARTIN-NORTHERN BREVARD-SOUTHERN BREVARD-ST. LUCIE. HIGH SURF ADVISORY UNTIL 11 AM EST WEDNESDAY FOR COASTAL VOLUSIA-INDIAN RIVER-MARTIN-NORTHERN BREVARD-SOUTHERN BREVARD- ST. LUCIE. COASTAL FLOOD WATCH THROUGH TUESDAY MORNING FOR INDIAN RIVER- MARTIN-ST. LUCIE. WIND ADVISORY FROM 7 AM TO 7 PM EST TUESDAY FOR COASTAL VOLUSIA- INDIAN RIVER-MARTIN-NORTHERN BREVARD-SOUTHERN BREVARD-ST. LUCIE. LAKE WIND ADVISORY FROM 7 AM TO 7 PM EST TUESDAY FOR INLAND VOLUSIA-NORTHERN LAKE-OKEECHOBEE-ORANGE-OSCEOLA-SEMINOLE- SOUTHERN LAKE. AM...SMALL CRAFT ADVISORY UNTIL 10 PM EST THIS EVENING FOR COASTAL WATERS FROM FLAGLER BEACH JUPITER INLET OUT TO 60 NM OFFSHORE. GALE WARNING FROM 10 PM THIS EVENING TO 4 PM EST TUESDAY FOR COASTAL WATERS FROM FLAGLER BEACH JUPITER INLET OUT TO 60 NM OFFSHORE. SMALL CRAFT ADVISORY FROM 4 PM TUESDAY TO 11 AM EST WEDNESDAY FOR COASTAL WATERS FROM FLAGLER BEACH JUPITER INLET OUT TO 60 NM OFFSHORE. && $$ SHORT TERM/AVIATION...BRAGAW LONG TERM/IMPACT WX...WIMMER
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1159 AM CST MON NOV 4 2013 .DISCUSSION... 344 AM CST OVERALL TRENDS OF MODELS OVER LAST COUPLE OF RUNS HAS BEEN FOR THE MORE PROGRESSIVE MODELS SLOWING DOWN AND THE LESS PROGRESSIVE MODELS...WHICH WERE THE MORE PREVALENT...MAINTAINING THEIR MOVEMENT OF THE UPPER TROUGH AND ASSOCIATED SURFACE BOUNDARY AND WAVES ACROSS THE CENTRAL U.S TUESDAY NIGHT THROUGH THURSDAY MORNING. ETA 04.00Z RUN STILL FASTEST IN BRINGING THE SYSTEM FROM THE PLAINS TO THE UPPER AND MID MS VALLEY AND THE UPPER MIDWEST OVERNIGHT TUESDAY THROUGH AND WEDNESDAY...WHICH A COUPLE OF GFS- ENSEMBLE PERTURBATIONS AGREE WITH THOUGH CERTAINLY NOT THE MAJORITY OR THE MEAN. WITH TIME EVEN THE QUICKER ETA SLOWS BY LATE WEDNESDAY NIGHT-EARLY THURSDAY MORNING TO AGREE WITH THE OTHER MODEL SOLUTIONS. 00Z GFS-ENSEMBLE MEANS IN GOOD AGREEMENT WITH SUITE OF MODELS AND 00Z OPERATIONAL GFS ALSO A GOOD FIT WITH ENSEMBLE MEANS WHILE RETAINING FINER DETAILS SEEN IN SOME OTHER MODELS THAT THE MEAN SMOOTHS OUT. THUS...FOR OVERALL TRENDS AM USING 00Z OPERATIONAL GFS. ALSO USING VARIOUS MODEL 850-700HPA QC FRONTOGENESIS PROGS WHICH ARE IN VERY GOOD AGREEMENT ACROSS THE REGION TONIGHT RIGHT THROUGH THURSDAY...WITH THE EXCEPTION OF THE SUSPECTED TOO QUICK ETA...AND MODEL QPF FIELDS DISREGARDING THOSE FROM THE 00Z ETA KEEPS THE LOCAL FORECAST AREA DRY OUTSIDE OF A FEW SPOTTY HUNDREDTH OR TWO AMOUNTS UNTIL LATER IN THE DAY TUESDAY WHEN CHANCES OF RAIN WILL BE SLIDING EASTWARD INTO THE NORTHWEST PORTION OF THE AREA AND THEN INCREASING TO LIKELY TO CATEGORICAL POPS FOR THE NORTHWEST 2/3RDS TO 3/4THS OF THE FORECAST AREA FOR OVERNIGHT TUESDAY AS THE UPPER TROUGH VERY SLOWLY PROGRESS EASTWARD OVER THE CENTRAL PLAINS AND UPPER AND MID MO VALLEY MID. ANY SIGNIFICANT PROGRESS OF THE PORTION OF THE UPPER TROUGH ACROSS THE CENTRAL AND SOUTHERN PLAINS IS TO BE IMPEDED THROUGH MID-WEEK BY A STRONG UPPER ANTICYCLONE PROGGED TO PARK ITSELF OVER THE EASTERN GULF OF MEXICO...FL...OFFSHORE OF THE SOUTHEASTERN ATLANTIC COAST...AND OVER THE BAHAMAS BEFORE SHIFTING SLOWLY SOUTHWARD TO OVER THE CARIBBEAN BY THURSDAY EVENING. GFS-ENSEMBLE PROBABILITIES OF VARIOUS QPF 6HR ACCUMULATION AMOUNTS FIT THE NOTION OF ONLY A MINIMAL CHANCE OF SIGNIFICANT RAIN SPREADING GRADUALLY EASTWARD WITH TIME DURING LATE TUESDAY THROUGH WEDNESDAY AFTERNOON...AND IS SUPPORTED BY 03Z SREF OUTPUT OF PROBABILITY OF QPF AMOUNTS. MODEL RUN ACCUM PRECIP PROGS SHOWING GENERALLY 1 TO 2 INCH TOTALS FALLING MAINLY FROM LATER TUESDAY NIGHT THROUGH MID TO LATE WEDNESDAY THOUGH NCEP WPC 1-3 DAY QPF TOTALS NOT AS GENEROUS ACROSS THE LOCAL AREA KEEPING A HEAVIER SOUTHWEST TO NORTHEAST BAND FROM EASTERN NE ACROSS IA TO FAR SOUTHEASTERN MN AND FAR SOUTHWESTERN WI WHERE THE MAIN BAROCLINIC BAND SETS UP FROM MONDAY NIGHT THROUGH TUESDAY NIGHT...AND ANOTHER HEAVIER BAND SOUTHWEST TO NORTHEAST FORM SOUTHERN MO ACROSS FAR SOUTHERN IL TO WEST CENTRAL IN WHERE THE BAROCLINIC BAND IS PROGGED TO BE OVER FROM LATER IN THE DAY WEDNESDAY THROUGH WEDNESDAY NIGHT. WHILE THIS MAY PLAY OUT BASED ON THE FACT THE SREF AND GFS-ENSEMBLE QPF FORECASTS AND PROBABILITY OF QPF AMOUNTS DONT SHOW THE HEAVIER RAIN BAND JUMPING OVER THE LOCAL AREA...RATHER SHOW A GRADUAL TRANSITION FROM NORTHWEST TO SOUTHEAST ACROSS THE REGION. THERE MAY BE LINGERING LIGHT RAIN/LIGHT SHOWERS WEDNESDAY NIGHT UNTIL THE MID AND UPPER LEVEL TROUGHS MOVE OVER AND EAST OF THE SOUTHEASTERN PORTION OF THE FORECAST AREA. MID LEVELS ARE SHOWN TO BY DRYING BY THEN BUT LOWER LEVELS REMAIN MOIST AS COOLING TEMPERATURES MAINTAIN MINIMAL DEW POINT DEPRESSIONS IN THE LOWER LEVELS SO CANNOT TOTALLY RULE OUT A MENTION OF SLIGHT CHANCE POPS. LOWER AND MID LEVEL WARM AIR ADVECTION IS HAS ALREADY BE UNDERWAY SINCE EARLIER TONIGHT. FORECAST TEMPERATURE PROFILES AND LOWER LEVEL TEMPERATURE PROGS STILL SUPPORT MID TO UPPER 50S ACROSS THE AREA TODAY...A FEW TO SEVERAL DEGREES ABOVE NORMALS FOR THE DATE. WITH AT LEAST MODEST WINDS THROUGH THE NIGHT...INCREASING CLOUD COVER AND ADDITIONAL WARM AIR ADVECTION TONIGHT LOWS SHOULD BE HELD UP INTO THE LOWER AND MID 40S...SEVERAL DEGREES ABOVE NORMAL. THE PERIOD OF MILDER WEATHER WILL PERSIST INTO WEDNESDAY AS THE AREA IS EXPECTED TO BE IN THE WARM SECTOR OF THE SYSTEM THOUGH TEMPERATURES MAY BE HELD TOWN JUST A BIT FROM REACHING THEIR MAXIMUM POTENTIAL ACROSS THE NORTH CENTRAL AND FAR NORTHEAST COUNTIES TUESDAY DUE THE EXPECTED PROLONGED PERIOD OF RAIN SPREADING OVER THE AREA. WHILE TUESDAY NIGHT SHOULD BE QUITE MILD FOR EARLY NOVEMBER THANKS TO UPPER 40S AND LOWER 50S GULF SOURCE DEW POINTS CONTINUE TO SPREAD NORTHWARD ACROSS THE REGION. WITH THE MODEL CONSENSUS SHOWING THAT THE UPPER TROUGH AXIS WILL BE A BIT MORE PROGRESSIVE RESULTING IN THE ASSOCIATED COLD FRONT MOVING SOUTHEASTWARD INTO THE NORTHWESTERN COUNTIES OF THE LOCAL FORECAST AREA DURING LATE MORNING-MIDDAY WEDNESDAY AND CONTINUING SLOWLY SOUTHEAST ACROSS THE FORECAST AREA AND THE SOUTHEASTERN COUNTIES DURING THE LATE AFTERNOON AN EARLY EVENING. THIS WOULD RESULT IN AN EARLIER ONSET OF COLD AIR ADVECTION WEDNESDAY LIMITING NORTHWESTERN PORTION OF THE FORECAST AREA TO SOMEWHAT COOLER TEMPERATURES DURING THE AFTERNOON AS IS CURRENTLY DEPICTED IN THE NDFD DATA BASE SO WILL MAKE SOME TWEAKS ON WEDNESDAY TO SHOW THIS ONSET OF COLD AIR ADVECTION SPREADING IN FROM THE NORTHWEST DURING WEDNESDAY. AFTER THIS UPPER TOUGH MOVES OFF TO THE CANADIAN MARITIMES...NEW ENGLAND AND OFF THE MID ATLANTIC COAST BY THURSDAY NIGHT-FRIDAY MORNING THE FLOW ACROSS NORTH AMERICA BECOMING ZONAL. THIS WILL PREVENT ANY SIGNIFICANT PENETRATION OF COLD AIR INTO THE LOCAL AREA AND BY OVERNIGHT THURSDAY AND FRIDAY LOW LEVEL WARM AIR ADVECTION WILL BE SPREADING FROM THE NORTHERN AND CENTRAL PLAINS TOWARD THE UPPER MIDWEST AND MID MS VALLEY AHEAD OF AN UPPER WAVE TO MOVE EAST FROM THE PACIFIC NORTHWEST ACROSS THE FAR NORTHERN PLAINS DURING THURSDAY AND FRIDAY BEFORE IT CROSSES THE UPPER MIDWEST AND CONTINUES TO THE UPPER GREAT LAKES SATURDAY MORNING. WITH A SURFACE RIDGE SPRAWLED FROM NORTHEASTERN MEXICO ACROSS EASTERN TX...THE LOWER MS VALLEY AND THE TN AND OH VALLEYS ALONG WITH THE ZONAL MID AND UPPER FLOW ANY SIGNIFICANT MOISTURE RETURN FROM THE WESTERN GULF WILL BE BLOCKED SO THE SYSTEM WILL ONLY HAVE WHAT EVER PACIFIC MOISTURE IS MANAGES TO BRING EAST OUT AHEAD OF IT ACROSS THE CASCADES AND THE NORTHERN ROCKIES TO WORK WITH. MODELS DEPICT MODERATELY STRONG DYNAMICS AND LIFT BUT A LACK OF DEEP MOISTURE IS EXPECTED TO LIMIT THE PRODUCTION OF PRECIPITATION...AND KEEP ANY OF IT NORTH OF NORTHERN IL FRIDAY NIGHT AND SATURDAY. LOW LEVEL FLOW BACKING TO OUT OF THE SOUTHWEST LATER FRIDAY AND INCREASING FRIDAY NIGHT INTO SATURDAY AHEAD OF THE SHORT WAVE TRAVELING EAST ALONG/NEAR THE 49TH PARALLEL THROUGH THE ZONAL FLOW WILL DRAW MILDER AIR BACK ACROSS THE REGION AND BRING TEMPERATURES BACK TO AROUND NORMALS. TRS && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 18Z... * STRONG S WINDS ARND 15KT GUSTING TO 20-30KT THROUGH LATE AFTN/EARLY EVENING. * SSW WINDS 10G15KT THROUGH LATE EVENING. * CHANCE OF -RA AT ORD TOMORROW AFTN. JEE //DISCUSSION...UPDATED 18Z... LOW PRESSURE IS OVER SOUTHERN MANITOBA WITH A LOW PRESSURE TROUGH EXTENDING THROUGH NORTHERN IOWA. THE THROUGH WILL LIFT TO THE NORTHEAST THROUGH THE REST OF TODAY AND EXPECTING VFR BKN TO OVC SKIES TO CONTINUE THROUGH TONIGHT. PRECIP WILL REMAIN WEST AND NORTH OF THE TERMINALS. SOUTH WINDS WILL CONTINUE TO GUST BTWN 25 AND 30KT THIS AFTN AND THEN DIMINISH TO 10G15 KT EARLY THIS EVENING AS THE PRESSURE GRADIENT WEAKENS OVERHEAD. WINDS SHOULD ALSO TURN SSW WITH GUSTS COMPLETELY DIMINISHING LATE THIS EVENING. THE NEXT SYSTEM FORMS OVER THE SW U.S. LATE TONIGHT/EARLY TUESDAY MORNING AND THEN MOVES NE TOWARD THE REGION. CIGS WILL LOWER TO LOW VFR TONIGHT AND THEN LOW VFR TO MVFR BY TUESDAY MORNING. MVFR IS MOST LIKELY AT RFD IN THE MORNING. WINDS WILL BE S OR SSE...ESPECIALLY AT ORD...WTH SPEEDS INCREASING TO AROUND 10 KT IN THE AFTERNOON. PRECIP WILL BE MOST LIKELY AT RFD LATE TOMORROW...WITH A CHANCE OF PRECIP AT ORD JEE //ORD AND MDW CONFIDENCE...UPDATED 18Z... * MEDIUM CONFIDENCE IN TIMING AND OCCURRENCE OF PRECIP AT ORD TOMORROW. * HIGH CONFIDENCE IN ALL OTHER FORECAST ELEMENTS. JEE //OUTLOOK FOR ORD/MDW FOR 00Z WEDNESDAY-12Z MONDAY...UPDATED 12Z... TUESDAY NIGHT...MODERATE SOUTH WINDS. MVFR DETERIORATING TO IFR IN RAIN. WEDNESDAY...MODERATE SOUTH WINDS SHIFTING WEST. IFR LIKELY IN RAIN. THURSDAY...MODERATE NW WINDS. BECOMING VFR. FRIDAY...VFR. SATURDAY...VFR. SLIGHT CHANCE OF A SHOWER. SUNDAY...VFR. ALLSOPP && .MARINE... 209 AM CST STRONG HIGH PRESSURE OVER EASTERN CANADA AND THE NORTHEAST US WILL DRIFT EAST TODAY. MEANWHILE...LOW PRESSURE WILL MOVE ACROSS MANITOBA TODAY. THIS WILL PRODUCE A TIGHT PRESSURE GRADIENT WHICH WILL GENERATE STRONG SOUTHEAST TO SOUTH WINDS TODAY. WILL CONTINUE THE GALE WARNING FOR THE NORTH 2/3 OF THE LAKE TODAY INTO THIS EVENING...AND SMALL CRAFT ADVISORY FOR THE NEARSHORE WATERS. HAVE ALSO EXTENDED THE GALE WARNING INTO THE SOUTH 1/3 OF THE LAKE THROUGH MID-LATE AFTERNOON AS A FEW GALE FORCE WIND GUSTS ARE EXPECTED. THE LOW WILL MOVE NORTHEAST INTO NORTHERN ONTARIO TONIGHT AND INTO HUDSON BAY TUESDAY...ALLOWING WINDS OVER LAKE MICHIGAN TO DIMINISH THIS EVENING FROM SOUTH TO NORTH. ANOTHER LOW PRESSURE OF 29.8 INCHES WILL DEVELOP OVER THE CENTRAL PLAINS TUESDAY EVENING. THIS LOW WILL MOVE NORTHEAST INTO LAKE MICHIGAN WEDNESDAY. THERE IS STILL SOME MODEL DISCREPANCY ON WHETHER THIS NEXT LOW WILL MOVE OVER THE SOUTH OR NORTH PART OF THE LAKE...AS WELL AS SOME TIMING DIFFERENCES. THERE IS THE POTENTIAL FOR STRONG SOUTH WINDS AGAIN TUESDAY NIGHT AHEAD OF THE LOW...AND STRONG WINDS OUT OF THE NORTHWEST ON THE BACKSIDE OF THE LOW WEDNESDAY. AT THIS TIME GALES ARE NOT ANTICIPATED...BUT WILL CONTINUE TO MONITOR. A QUIETER PERIOD IS EXPECTED FOR THE LATER HALF OF THE WEEK. ALLSOPP && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...GALE WARNING...LMZ080-LMZ777-LMZ779-LMZ878 UNTIL 3 PM MONDAY. GALE WARNING...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-LMZ567- LMZ669-LMZ671-LMZ673-LMZ675-LMZ868-LMZ870-LMZ872-LMZ874- LMZ876 UNTIL 9 PM MONDAY. SMALL CRAFT ADVISORY...NEARSHORE GARY TO MICHIGAN CITY IN UNTIL 9 PM MONDAY. SMALL CRAFT ADVISORY...NEARSHORE WINTHROP HARBOR TO GARY IN UNTIL 3 AM TUESDAY. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion National Weather Service Lincoln IL 1146 AM CST Mon Nov 4 2013 .DISCUSSION... ISSUED 950 AM CST Mon Nov 4 2013 Morning surface analysis shows cold front extending from western Minnesota to the Texas panhandle. Stream of mainly mid/high-level moisture well ahead of the front has produced a swath of cloudiness from the western Gulf Coast into the Great Lakes. Generally high clouds blanket central Illinois: however, clouds have lowered to between 5000 and 9000ft further west across Iowa into Missouri, where a few light showers have been occurring from time to time. HRRR suggests these showers will continue to push eastward and dissipate across west-central Illinois this afternoon. 12z KILX upper air sounding was quite dry below 500mb, so do not believe measurable precip will occur anywhere across the area today. However based on radar trends and upstream obs, have added scattered sprinkles across the Illinois River Valley. Main story today will be the breezy and warm conditions. Southerly winds gusting to between 25 and 30 mph will boost afternoon high temperatures into the lower 60s. Zone update has already been issued. Barnes && .AVIATION... ISSUED 1146 AM CST Mon Nov 4 2013 VFR conditions are expected through the entire 18z TAF period. Mid/high clouds will be prevalent across central Illinois over the next 24 hours, with lower clouds generally remaining just west of the area until Tuesday evening. A lead short-wave ahead of a slowly approaching cold front may potentially bring MVFR ceilings and a few light showers Tuesday morning: however, confidence for those conditions is not high enough to include in the forecast at this time. Have lowered ceilings to around 3500ft and introduced VCSH as this wave passes between 13z and 18z. Winds will be strong/gusty from the south this afternoon, with gusts occasionally reaching 25kt. Gusts will subside tonight, but sustained southerly winds of 10 to 15kt are expected to continue overnight into Tuesday morning. Barnes && .PREV DISCUSSION... ISSUED 330 AM CST Mon Nov 4 2013 SHORT TERM...Today through Wednesday night 00Z models continue slower trend of bringing in qpf into central and southeast IL Tue, especially the NAM model which keeps our CWA dry until late Tuesday evening & Tue overnight. Did not go that dry yet but did trend lower with pops on Tuesday. Best chances of rain appears to be from overnight Tue night through Wed evening with around 1 inch of rain expected, and perhaps a bit higher over southeast IL. Early morning surface map shows strong 1038 mb high pressure over western Quebec and Lake Ontario while 1000 mb low pressure was wst of Lake Winnipeg with its cold front extending southward through eastern Dakotas, eastern Nebraska and central Kansas. Shield of high/cirrus clouds 20-25k ft blankets IL and se winds 5-15 mph keeping milder/nearly steady temps in the low to mid 40s. Aloft an upper level ridge was east of the MS river from MI and the Ohio River valley into AL/GA, while 532 dm 500 mb low was over southern Saskatchewan with large upper level trof over the Rockies. IL was getting into a sw upper level flow early today. Models show high clouds thinning somewhat during the day so some sunshine to filter through the cirrus clouds with partly to mostly cloudy skies expected today. Breezy south winds gusting 20-30 mph by afternoon to give milder highs of 59-63F. Dry conditions to prevail tonight with clouds thickening and lowering especially west of I-57. Lows of 44-48 degrees tonight. A warm front sets up nw of IL Tuesday with 20-30% chance of light rain showers west of I-57 Tuesday morning and increasing to 30-50% Tuesday afternoon, with just slight chance of light rain showers in eastern IL Tue afternoon while staying dry over the Wabash River valley in southeast IL. Highs mostly in the lower 60s again on Tuesday. A vigorous short wave to dig into the Central Plains Tues night and eject ne into the western Great Lakes Wed. Deepening surface low pressure ejecting ne from central plains to drag a cold front east through IL Wednesday and exiting southeast IL during Wed evening. This to bring our best chance of rain showers especially over IL River valley Tuesday night and shifting eastward into eastern IL on Wednesday. Rain chances then diminish from west to east during Wed night. Kept just slight chance of thunderstorms east of I-57 Wed but SPC currently does not carry thunderstorm chances through Day 3 outlooks over IL. Highs Wed range from mid 50s nw of IL River to lower 60s in southeast IL. LONG TERM...Thursday through Sunday night Dry weather expected to prevail across IL Thursday through Sunday along with cooler temperatures with frosty lows near or just below freezing Thursday night. A fairly strong upper level short wave tracks into the western great lakes region late this week but still appears to keep its light rain shower chances north of central IL Friday night and Saturday. Temps that modify a bit late this week to cool back down on Sunday behind this weather system. 07 && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
920 PM EST TUE NOV 5 2013 .UPDATE... THE AVIATION SECTION HAS BEEN UPDATED BELOW. && .SYNOPSIS... ISSUED AT 231 PM EST TUE NOV 5 2013 A COLD FRONT IS EXPECTED TO MOVE ACROSS THE FORECAST AREA DURING THE DAY ON WEDNESDAY. IN THE WAKE OF THIS FRONT...HIGH PRESSURE WILL BUILD IN AND LINGER INTO THE WEEKEND. ANOTHER FRONTAL SYSTEM MAY APPROACH THE AREA EARLY NEXT WEEK. && .NEAR TERM /TONIGHT/... ISSUED AT 720 PM EST TUE NOV 5 2013 INTRODUCED SOME SLIGHT CHANCE POPS INTO THE NW FORECAST AREA A FEW HOURS EARLIER THAN PRIOR FORECAST TO ACCOUNT FOR UPSTREAM ECHOES OVER CENTRAL ILLINOIS AND HRRR OUTPUT SUPPORTING THE POTENTIAL FOR A FEW DROPS FROM THESE ECHOES EARLIER THAN 06Z. REMAINDER OF FORECAST IN GOOD SHAPE. PREVIOUS DISCUSSION FOLLOWS. ISSUED AT 231 PM EST TUE NOV 5 2013 DON/T SEE MUCH IN THE WAY OF SIGNIFICANT LIFT ACROSS THE AREA UNTIL THE EARLY MORNING HOURS ON WEDNESDAY...WHEN A STRONG LOW LEVEL JET AROUND 50 KTS IS PROGGED TO MOVE OVER THE NORTHWEST ZONES. EVEN THEN...THE ORIENTATION OF THE LOW LEVEL JET SUGGEST THE BEST LIFT/PRECIPITATION THREAT WILL STAY OFF TO THE WEST OF THE FORECAST AREA TONIGHT. WILL GO WITH CHANCE POPS AFTER 060600Z...HIGHEST IN THE NORTHWEST. LOW LEVEL THICKNESS PROGS SUGGEST THE GFS MOS LOWS TONIGHT LOOK REASONABLE...SO ONLY MINOR ADJUSTMENTS WILL BE MADE. && .SHORT TERM /WEDNESDAY THROUGH FRIDAY/... ISSUED AT 231 PM EST TUE NOV 5 2013 MODEL DATA INDICATE A COLD FRONT WILL BEGIN MOVING INTO THE FAR NORTHWEST ZONES AROUND MIDDAY ON WEDNESDAY...REACHING THE SOUTHEAST ZONES BY EVENING. FORCING NEAR THE FRONT SHOULD BE QUITE STRONG...GIVEN AN ASSOCIATED 50-55 KT LOW LEVEL JET. WILL GO WITH HIGH POPS ALL AREAS BY THE LATE MORNING THROUGH THE AFTERNOON HOURS. LAPSE RATES/INSTABILITY LOOK GENERALLY POOR ON WEDNESDAY. SO DESPITE THE GOOD FORCING...NOT EXPECTING MUCH IN THE WAY OF LIGHTNING. LIFTING STILL LOOKS PRETTY GOOD OVER THE EASTERN ZONES BY EARLY EVENING WEDNESDAY...BUT SHOULD TAPER OFF QUICKLY LATER IN THE NIGHT. AS A RESULT...WILL KEEP SOME POPS GOING INTO THE EARLY MORNING HOURS ON THURSDAY...HIGHEST IN THE EAST. REST OF THE SHORT TERM LOOKS QUIET WITH HIGH PRESSURE SETTLING INTO THE OHIO VALLEY. GIVEN THE WIDESPREAD RAIN EXPECTED ON WEDNESDAY...THE GFS MOS HIGHS MAY BE A LITTLE WARM AT THAT TIME...ESPECIALLY IN THE EAST. WILL NUDGE THE GUIDANCE DOWN A COUPLE OF DEGREES IN THOSE AREAS. GUIDANCE TEMPERATURES FOR THE REST OF THE PERIOD LOOK REASONABLE BASED ON LOW LEVEL THICKNESSES. && .LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/... ISSUED AT 203 PM EST TUE NOV 5 2013 FOR THE DURATION OF THE EXTENDED PERIOD FLOW WILL BE ZONAL WITH SEVERAL DISTURBANCES RIDING NORTH OF THE AREA...NOT QUITE MAKING IT THIS FAR SOUTH TO MENTION ANY RAIN UNTIL TUESDAY. HIGH PRESSURE WILL BE OVER THE OHIO VALLEY FRIDAY/FRIDAY NIGHT FOLLOWED BY A COLD FRONT LATE SATURDAY AND THEN BY ANOTHER HIGH PRESSURE SYSTEM SUNDAY. TEMPS GENERALLY EXPECTED AROUND NORMAL. ALLBLEND GUIDANCE DEPICTED THIS PATTERN VERY WELL SO DID NOT NEED TO DEVIATE FAR FROM FORECAST. && .AVIATION /DISCUSSION FOR THE 060300Z IND TAF UPDATE/... ISSUED AT 920 PM EST TUE NOV 5 2013 NO UPDATE NEEDED TO TAF. PREVIOUS DISCUSSION FOLLOWS... VFR CONDITIONS EXPECTED TO DETERIORATE TO MVFR OR WORSE AFTER 14Z WEDNESDAY AS DEEP MOISTURE AND STRONG LIFT ARE SET TO OCCUR AHEAD OF AN ADVANCING COLD FRONT THAT WILL REACH LAF AND HUF NEAR 20Z AND IND AND BMG NEAR 22Z. LOW LEVEL WIND SHEAR WILL ALSO BE A CONCERN AS A 50 KNOT LOW LEVEL JET SETS UP AHEAD OF THE FRONT AFTER 06Z AT THE WESTERN SITES AND AFTER 09Z ACROSS THE EASTERN SITES. BY 14Z..ENOUGH MIXING SHOULD TAKE PLACE TO PULL THE WIND SHEAR WITH SOUTHWEST WINDS GUSTING TO NEAR 25 KNOTS. MEANWHILE...SHOULD SEE SHOWER CHANCES INCREASING OVERNIGHT WITH BEST CHANCE OF RAIN OVERSPREADING THE TAF SITES AFTER 12Z...STARTING OFF AT LAF AND HUF. && .IND WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SYNOPSIS...JAS NEAR TERM...JAS/NIELD SHORT TERM...JAS LONG TERM....SMF AVIATION...MK VISIT US AT HTTP://WWW.WEATHER.GOV/IND FOLLOW US ON TWITTER AND YOUTUBE AT: WWW.TWITTER.COM/NWSINDIANAPOLIS WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
720 PM EST TUE NOV 5 2013 .UPDATE... THE NEAR TERM SECTION HAS BEEN UPDATED BELOW. && .SYNOPSIS... ISSUED AT 231 PM EST TUE NOV 5 2013 A COLD FRONT IS EXPECTED TO MOVE ACROSS THE FORECAST AREA DURING THE DAY ON WEDNESDAY. IN THE WAKE OF THIS FRONT...HIGH PRESSURE WILL BUILD IN AND LINGER INTO THE WEEKEND. ANOTHER FRONTAL SYSTEM MAY APPROACH THE AREA EARLY NEXT WEEK. && .NEAR TERM /TONIGHT/... ISSUED AT 720 PM EST TUE NOV 5 2013 INTRODUCED SOME SLIGHT CHANCE POPS INTO THE NW FORECAST AREA A FEW HOURS EARLIER THAN PRIOR FORECAST TO ACCOUNT FOR UPSTREAM ECHOES OVER CENTRAL ILLINOIS AND HRRR OUTPUT SUPPORTING THE POTENTIAL FOR A FEW DROPS FROM THESE ECHOES EARLIER THAN 06Z. REMAINDER OF FORECAST IN GOOD SHAPE. PREVIOUS DISCUSSION FOLLOWS. ISSUED AT 231 PM EST TUE NOV 5 2013 DON/T SEE MUCH IN THE WAY OF SIGNIFICANT LIFT ACROSS THE AREA UNTIL THE EARLY MORNING HOURS ON WEDNESDAY...WHEN A STRONG LOW LEVEL JET AROUND 50 KTS IS PROGGED TO MOVE OVER THE NORTHWEST ZONES. EVEN THEN...THE ORIENTATION OF THE LOW LEVEL JET SUGGEST THE BEST LIFT/PRECIPITATION THREAT WILL STAY OFF TO THE WEST OF THE FORECAST AREA TONIGHT. WILL GO WITH CHANCE POPS AFTER 060600Z...HIGHEST IN THE NORTHWEST. LOW LEVEL THICKNESS PROGS SUGGEST THE GFS MOS LOWS TONIGHT LOOK REASONABLE...SO ONLY MINOR ADJUSTMENTS WILL BE MADE. && .SHORT TERM /WEDNESDAY THROUGH FRIDAY/... ISSUED AT 231 PM EST TUE NOV 5 2013 MODEL DATA INDICATE A COLD FRONT WILL BEGIN MOVING INTO THE FAR NORTHWEST ZONES AROUND MIDDAY ON WEDNESDAY...REACHING THE SOUTHEAST ZONES BY EVENING. FORCING NEAR THE FRONT SHOULD BE QUITE STRONG...GIVEN AN ASSOCIATED 50-55 KT LOW LEVEL JET. WILL GO WITH HIGH POPS ALL AREAS BY THE LATE MORNING THROUGH THE AFTERNOON HOURS. LAPSE RATES/INSTABILITY LOOK GENERALLY POOR ON WEDNESDAY. SO DESPITE THE GOOD FORCING...NOT EXPECTING MUCH IN THE WAY OF LIGHTNING. LIFTING STILL LOOKS PRETTY GOOD OVER THE EASTERN ZONES BY EARLY EVENING WEDNESDAY...BUT SHOULD TAPER OFF QUICKLY LATER IN THE NIGHT. AS A RESULT...WILL KEEP SOME POPS GOING INTO THE EARLY MORNING HOURS ON THURSDAY...HIGHEST IN THE EAST. REST OF THE SHORT TERM LOOKS QUIET WITH HIGH PRESSURE SETTLING INTO THE OHIO VALLEY. GIVEN THE WIDESPREAD RAIN EXPECTED ON WEDNESDAY...THE GFS MOS HIGHS MAY BE A LITTLE WARM AT THAT TIME...ESPECIALLY IN THE EAST. WILL NUDGE THE GUIDANCE DOWN A COUPLE OF DEGREES IN THOSE AREAS. GUIDANCE TEMPERATURES FOR THE REST OF THE PERIOD LOOK REASONABLE BASED ON LOW LEVEL THICKNESSES. && .LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/... ISSUED AT 203 PM EST TUE NOV 5 2013 FOR THE DURATION OF THE EXTENDED PERIOD FLOW WILL BE ZONAL WITH SEVERAL DISTURBANCES RIDING NORTH OF THE AREA...NOT QUITE MAKING IT THIS FAR SOUTH TO MENTION ANY RAIN UNTIL TUESDAY. HIGH PRESSURE WILL BE OVER THE OHIO VALLEY FRIDAY/FRIDAY NIGHT FOLLOWED BY A COLD FRONT LATE SATURDAY AND THEN BY ANOTHER HIGH PRESSURE SYSTEM SUNDAY. TEMPS GENERALLY EXPECTED AROUND NORMAL. ALLBLEND GUIDANCE DEPICTED THIS PATTERN VERY WELL SO DID NOT NEED TO DEVIATE FAR FROM FORECAST. && .AVIATION /DISCUSSION FOR THE 060000Z TAF ISSUANCE/... ISSUED AT 624 PM EST TUE NOV 5 2013 VFR CONDITIONS EXPECTED TO DETERIORATE TO MVFR OR WORSE AFTER 14Z WEDNESDAY AS DEEP MOISTURE AND STRONG LIFT ARE SET TO OCCUR AHEAD OF AN ADVANCING COLD FRONT THAT WILL REACH LAF AND HUF NEAR 20Z AND IND AND BMG NEAR 22Z. LOW LEVEL WIND SHEAR WILL ALSO BE A CONCERN AS A 50 KNOT LOW LEVEL JET SETS UP AHEAD OF THE FRONT AFTER 06Z AT THE WESTERN SITES AND AFTER 09Z ACROSS THE EASTERN SITES. BY 14Z..ENOUGH MIXING SHOULD TAKE PLACE TO PULL THE WIND SHEAR WITH SOUTHWEST WINDS GUSTING TO NEAR 25 KNOTS. MEANWHILE...SHOULD SEE SHOWER CHANCES INCREASING OVERNIGHT WITH BEST CHANCE OF RAIN OVERSPREADING THE TAF SITES AFTER 12Z...STARTING OFF AT LAF AND HUF. && .IND WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SYNOPSIS...JAS NEAR TERM...JAS/NIELD SHORT TERM...JAS LONG TERM....SMF AVIATION...MK VISIT US AT HTTP://WWW.WEATHER.GOV/IND FOLLOW US ON TWITTER AND YOUTUBE AT: WWW.TWITTER.COM/NWSINDIANAPOLIS WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS WICHITA KS
323 PM CST MON NOV 4 2013 .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 323 PM CST MON NOV 4 2013 FORECAST HIGHLIGHTS INCLUDE WIDESPREAD RAIN CHANCES LATE TONIGHT THROUGH TUESDAY NIGHT. A STALLED FRONTAL BOUNDARY CURRENTLY DRAPED ACROSS SOUTHEAST KS WILL GRADUALLY LIFT NORTHWARD TONIGHT IN RESPONSE TO A DEEPENING WESTERN CONUS TROUGH. LOW-LEVEL MOISTURE ADVECTION IN WAKE OF THIS WARM FRONT WILL RESULT IN INCREASING LOW CLOUDS...ALONG WITH EVENTUAL DRIZZLE FOR MOST AREAS BY LATE EVENING OR MIDNIGHT. COULD ALSO SEE AREAS OF FOG GENERALLY NORTHWEST OF THE KS TURNPIKE...AS THE INCREASED MOISTURE ADVECTION INTERACTS WITH A CHILLY RADIATED- OUT AIRMASS. ANTICIPATING WIDESPREAD RAIN AND PERHAPS A FEW EMBEDDED THUNDERSTORMS AREAWIDE TUESDAY...AS STRONG 850-600MB WARM/MOIST ADVECTION COMMENCES AHEAD OF THE APPROACHING TROUGH. GIVEN THE STRONG FORCING AND ABOVE-AVERAGE PRECIPITABLE WATER VALUES...THINKING WIDESPREAD ONE-QUARTER TO ONE-HALF INCH RAINFALL AMOUNTS ARE LIKELY...WITH AMOUNTS LIKELY EXCEEDING THREE-QUARTERS OF AN INCH TO ONE INCH OVER SOUTHEAST KS. ANTICIPATING PRECIPITATION TO GRADUALLY EXIT THE REGION TO THE EAST TUESDAY NIGHT. AS COLDER AIR FILTERS SOUTH IN WAKE OF THE COLD FRONT...CANNOT RULE OUT A BRIEF PERIOD OF RAIN/SNOW MIX OVER CENTRAL KS LATE TUE NIGHT...ESPECIALLY IF THE NAM`S DEPICTION OF A LINGERING MID-LEVEL BAROCLINIC ZONE AHEAD OF THE APPROACHING TROUGH HOLDS TRUE. EITHER WAY...NOT ANTICIPATING ACCUMULATIONS. SUNNY YET COOLER TEMPERATURES ANTICIPATED WEDNESDAY IN WAKE OF THIS SYSTEM...WITH 850MB TEMPERATURES AND EXPECTED MIXING SUPPORTING HIGHS NEAR 50 DEGREES. ADK && .LONG TERM...(THURSDAY THROUGH MONDAY) ISSUED AT 323 PM CST MON NOV 4 2013 FAIRLY QUIET WEATHER ANTICIPATED THURSDAY THROUGH THE WEEKEND...WITH NEARLY ZONAL FLOW ACROSS MUCH OF THE NATION. HOWEVER...SIMILAR TO YESTERDAY (SUNDAY)...STRONG/GUSTY SOUTH WINDS ARE ANTICIPATED FRIDAY...AS A FAST-MOVING SHORTWAVE PROGRESSES ACROSS THE NORTHERN PLAINS. OTHERWISE...TEMPERATURES THROUGH THE WEEKEND WILL BE NEAR TO SLIGHTLY BELOW NORMAL IN THE UPPER 50S TO LOW 60S...WITH MOSTLY CLEAR AND DRY CONDITIONS ANTICIPATED. ADK && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 1128 AM CST MON NOV 4 2013 MVFR CLOUDS CONTINUE EXITING EASTERN KS AS OF 1730Z. THE COLD FRONT WAS LOCATED NEAR A KMHK-KICT-KAWK AND WAS STILL ADVANCING EAST. THIS SHOULD BE TEMPORARY. THE RAP MODEL RUNS HAVE CAPTURED THE LOCATION OF THE FRONT MUCH BETTER THAN ANY OF THE OTHER MODELS FROM THE 12Z CYCLE THIS MORNING. USED THIS AS THE PRIMARY FORECAST MEANS. LOW CLOUDS SHOULD DEVELOP AROUND 06Z WITH CIGS MOSTLY AROUND 7 HUNDRED FEET. VSBYS WILL DROP TO 4 MILES WITH LIGHT DRIZZLE DURING THIS TIME. CONDITIONS WILL REMAIN THE SAME THROUGH MOST OF TUESDAY WITH INCREASING SHOWERS AND WINDS FROM THE SOUTH AT 15 TO 25 KNOTS. COOK && .PRELIMINARY POINT TEMPS/POPS... WICHITA-KICT 53 58 37 50 / 70 80 80 10 HUTCHINSON 48 58 35 50 / 70 80 70 10 NEWTON 50 57 36 49 / 70 80 80 10 ELDORADO 53 57 38 49 / 70 80 90 10 WINFIELD-KWLD 56 59 40 51 / 70 90 90 20 RUSSELL 42 58 31 49 / 60 90 60 0 GREAT BEND 43 59 32 50 / 70 90 60 0 SALINA 46 59 34 50 / 70 90 70 0 MCPHERSON 47 58 35 49 / 70 80 70 10 COFFEYVILLE 55 60 45 52 / 70 90 100 30 CHANUTE 54 59 42 51 / 70 90 100 30 IOLA 54 59 41 51 / 70 90 100 30 PARSONS-KPPF 55 60 44 52 / 70 90 100 30 && .ICT WATCHES/WARNINGS/ADVISORIES...NONE. && $$
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1157 AM CST Mon Nov 4 2013 ...Updated Synopsis and Aviation sections... .SYNOPSIS... ISSUED AT 1156 AM CST MON NOV 4 2013 A longwave trough encompassed much of western/central North America with large scale ridging across eastern North America and across the far northeast Pacific (west and south of British Columbia). There was a significant polar jet streak rounding the western ridge and diving southeast across the west coast of Washington-Oregon-Northern California. There were a couple of shortwave perturbations that were lifting northeast through the northern Great Plains into the eastern Canadian Prairies. Tied to these features, there was a fairly significant 700mb cold front moving south through Nebraska into northwestern Kansas. This baroclinic zone was quasi-stationary as it extended southwest through southern Colorado west to southern Nevada. Temperatures were cold over a large area at 700mb with -12 to -15C common across the northern High Plains into the northern Rockies. There were two cold fronts that could be identified at 850mb. The first one pushed through southwestern Kansas early this morning where 850mb temperatures were falling into the lower single digits. The second northern front was pushing through South Dakota early this morning with 850mb temperatures behind this front as cold as -9C at Glasgow, MT. Low level moisture was on the increase with 850mb dewpoint temperatures around +10C across the lower Rio Grande Valley (Del Rio, TX with a south wind). && .SHORT TERM...(Today and tonight) ISSUED AT 230 AM CST MON NOV 4 2013 Today will see a cold front sweep through rather quickly and early from the northwest to the southeast. For much of the day, mostly sunny skies will prevail and winds will be northeast at 10 to 20 mph and gusty. This will allow temperatures to start to warm up early, but level off and stabilize in the mid 50s in the northwest, such as from Johnson City to Wakeeney. Temperatures in the Pratt, Barber, and Comanche county areas will top out in the mid 60s, prior to the front passing through. Then as the lower level flow shifts more easterly tonight, and a mid level trough advances east from Colorado, rain should start toward 06z, but I did lower Pops a little until after 09z. The HRRR and RUC13 models hold off any rain until after 09z, while the NAM and GFS begin rain before 09z. It appears the south and southwestern zones of Grant, Stevens, Morton and Stanton counties may be dry-slotted early in the precip event, with the mid and upper wave coming in. The highest precipitation chances will be in the eastern half of our forecast area, and mainly after 09z. Precipitation chances for rain will increase to likely by 12z, and the southeast zones southeast of a line from Stafford to Edwards to Clark counties will have showers with isolated thunderstorms mentioned. The front will have advected north as a warm front by late Monday night, and there could be enough lift for some scattered convection. As far as temperatures tonight, winds and precip may hold temperatures up, ranging from the upper 30s in the Scott City and Syracuse areas, to the lower 50s in the Ashland to Saint John areas. Rainfall amounts are always challenging, with light precip starting prior to 06z, and more substantial rain between 06Z and 12Z. .LONG TERM...(Tuesday through Sunday) ISSUED AT 351 AM CST MON NOV 4 2013 The main focus continues to be on the day 2 and 3 synoptic trough that will create impacts for Kansas. The models including the GFS, ECMWF and WRF 40 KM all generally agree on the timing of strong warm air and including dew points, theta-e advection from surface to above the 850 mb level early Tuesday morning. The model data show broad isentropic lift across areas west of Dodge City to the Colorado line, around 12 UTC with MUCAPES on the order of 500-900 Joules/kg. The area of instability and lift will shift eastward during the day as the trough axis and deeper cold air move into eastern Colorado. As a result, the precipitation probabilities were increased to around 80 percent with the isentropic lift/warm air advection timeframe. Precipitation type will likely be rain, rain showers or a rain snow mix as well after the initial frontal boundary moves through southwest Kansas. The best chances for any snow will be across west central Kansas, say from Hays to Dighton and Syracuse, where thermal profiles are most supportive before frontogenetic response lifting become essentially zero. Widespread temperatures falling into the mid 20`s are likely Tuesday night and early Wednesday morning west of a Hays to Cimarron to Hugoton line. The remainder of the forecast period will bring a day or so of upper ridging around Thursday before another westerly fast moving intense upper shortwave crashes into the Central or Northern Plains Friday. Cool and cloudy conditions on Wednesday will change to sunny and warmer in the 50`s and maybe 60`s by Friday before the next wave contributes to slightly cooler conditions. && .AVIATION...(For the 18Z TAFS through 18Z Tuesday afternoon) ISSUED AT 1156 AM CST MON NOV 4 2013 Aviation weather conditions will deteriorate overnight tonight as low level moisture pushes north-northwest into the southwest Kansas region. This will result in development of MVFR stratus after 07Z or so late tonight...with IFR stratus expected a few hours after that. Eventually, close to daybreak Tuesday, the ceiling will likely fall to LIFR category with rain overspreading the region. Light rain is expected to be off and on during much of the morning Tuesday as an approaching upper level disturbance increased the atmospheric lift across the western Kansas region. && .PRELIMINARY POINT TEMPS/POPS... DDC 59 46 62 30 / 0 60 90 70 GCK 58 43 57 25 / 0 30 80 60 EHA 57 40 61 28 / 10 20 90 70 LBL 60 46 62 30 / 10 40 90 80 HYS 60 42 56 28 / 0 70 90 50 P28 66 52 63 36 / 10 60 80 90 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...Umscheid SHORT TERM...Burke LONG TERM...Russell AVIATION...Umscheid
AREA FORECAST DISCUSSION
NWS WICHITA KS
1137 AM CST MON NOV 4 2013 .SYNOPSIS... ISSUED AT 308 AM CST MON NOV 4 2013 WATER VAPOR IMAGERY SHOWS A NUMBER OF FEATURES WITHIN THE MEAN UPPER TROUGH OVER THE WESTERN CONUS. ONE WEAK IMPULSE IS LIFTING OVER THE UPPER MISSISSIPPI VALLEY. MEANWHILE...SOME SHORTWAVE ENERGY IS TRACKING EAST OVER THE NORTHERN HIGH PLAINS. LAST BUT NOT LEAST...ANOTHER STRONG SHORTWAVE IS DIVING SOUTHEAST OVER THE NORTHERN INTER-MOUNTAIN. AT THE SURFACE...TROUGHING/COLD FRONT EXTENDS FROM THE EASTERN DAKOTAS AND DOWN INTO WEST-CENTRAL KS. && .SHORT TERM...(TODAY THROUGH WEDNESDAY) ISSUED AT 308 AM CST MON NOV 4 2013 TODAY THE PLAINS WILL BE BETWEEN TWO SYSTEMS. ONE MOVING OUT OF THE NORTHERN HIGH PLAINS AND INTO THE UPPER MISSISSIPPI VALLEY WITH ADDITIONAL SHORTWAVE ENERGY DIVING SOUTHEAST ACROSS THE GREAT BASIN. SURFACE LOW PRESSURE WILL STRENGTHEN OVER THE SOUTHERN HIGH PLAINS TODAY WHICH WILL ALLOW BETTER MOISTURE TO STREAM NORTH. WIDESPREAD SHOWERS AND ISO STORMS ARE EXPECTED TO OVERSPREAD THE ENTIRE AREA TONIGHT FROM SOUTH TO NORTH AS DEEP MOISTURE TRANSPORT INCREASES IN THE 300-305K LAYER. WHILE THERE WILL BE A SHOT AT A FEW STORMS...INSTABILITY WILL LIMIT THE AREAL COVERAGE. ALSO WOULDN`T BE SHOCKED TO SEE PERIODS OF HEAVY DRIZZLE TUE AS THE BULK OF OF THE SATURATION REMAINING IN THE LOW LEVELS. BY TUE MORNING THE SHORTWAVE TROUGH WILL BE APPROACHING THE ROCKIES WITH RICH LOW LEVEL MOISTURE CONTINUING TO STREAM INTO THE AREA. THERE IS SOME MODEL AGREEMENT THAT THE DRY SLOT MAY MOVE OVER THE AREA FOR TUE. HOWEVER...WITH THE LOW LEVELS STILL EXTREMELY SATURATED...STILL THINK WE`LL SEE SOME SHOWERS OR EVEN SOME DRIZZLE. THIS SYSTEM WILL CONTINUE ITS PROGRESSIVE NATURE AND WILL QUICKLY SWING ACROSS THE PLAINS ON TUE NIGHT. BY WED MORNING ONLY FAR SE KS WILL STILL BE SEEING SHOWERS AND ISO STORMS. NOT OVERLY EXCITED ABOUT WINTRY PRECIPITATION OVER CENTRAL KS DUE TO LACK OF CLOUD ICE ONCE THE LOW LEVEL FINALLY BECOME COLD ENOUGH. .LONG TERM...(THURSDAY THROUGH SUNDAY) ISSUED AT 308 AM CST MON NOV 4 2013 THE MAIN THEME THROUGH THESE EXTENDED PERIODS WILL BE A RETURN TO SEASONAL TEMPS AND DRY CONDITIONS. BOTH THE ECMWF AND GFS AGREE ON TRACKING A FAST MOVING IMPULSE OUT OF THE PACIFIC NW AND ACROSS THE CENTRAL PLAINS ON FRI. THIS FEATURE IS EXPECTED TO STAY FAR ENOUGH NORTH TO LIMIT PRECIPITATION CHANCES. ZONAL UPPER FLOW WILL HELP KEEP MILD TEMPS IN PLACE THROUGH THESE EXTENDED PERIODS ALONG WITH DRY CONDITIONS. LAWSON && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 1128 AM CST MON NOV 4 2013 MVFR CLOUDS CONTINUE EXITING EASTERN KS AS OF 1730Z. THE COLD FRONT WAS LOCATED NEAR A KMHK-KICT-KAWK AND WAS STILL ADVANCING EAST. THIS SHOULD BE TEMPORARY. THE RAP MODEL RUNS HAVE CAPTURED THE LOCATION OF THE FRONT MUCH BETTER THAN ANY OF THE OTHER MODELS FROM THE 12Z CYCLE THIS MORNING. USED THIS AS THE PRIMARY FORECAST MEANS. LOW CLOUDS SHOULD DEVELOP AROUND 06Z WITH CIGS MOSTLY AROUND 7 HUNDRED FEET. VSBYS WILL DROP TO 4 MILES WITH LIGHT DRIZZLE DURING THIS TIME. CONDITIONS WILL REMAIN THE SAME THROUGH MOST OF TUESDAY WITH INCREASING SHOWERS AND WINDS FROM THE SOUTH AT 15 TO 25 KNOTS. COOK && .PRELIMINARY POINT TEMPS/POPS... WICHITA-KICT 62 53 60 37 / 10 60 90 70 HUTCHINSON 62 50 59 35 / 10 60 80 70 NEWTON 61 51 59 35 / 10 60 90 70 ELDORADO 62 52 60 38 / 10 60 90 80 WINFIELD-KWLD 64 53 60 38 / 10 60 90 70 RUSSELL 61 44 54 29 / 10 70 90 30 GREAT BEND 60 45 56 31 / 10 70 80 50 SALINA 63 47 58 34 / 10 70 90 60 MCPHERSON 61 49 58 34 / 10 60 80 70 COFFEYVILLE 66 51 60 48 / 10 50 90 90 CHANUTE 64 53 59 45 / 10 50 90 90 IOLA 65 53 59 44 / 10 50 90 80 PARSONS-KPPF 65 52 59 47 / 10 50 90 90 && .ICT WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
552 AM CST Mon Nov 4 2013 ...UPDATED FOR THE AVIATION DISCUSSION... .SHORT TERM...(Today and tonight) ISSUED AT 230 AM CST MON NOV 4 2013 Today will see a cold front sweep through rather quickly and early from the northwest to the southeast. For much of the day, mostly sunny skies will prevail and winds will be northeast at 10 to 20 mph and gusty. This will allow temperatures to start to warm up early, but level off and stabilize in the mid 50s in the northwest, such as from Johnson City to Wakeeney. Temperatures in the Pratt, Barber, and Comanche county areas will top out in the mid 60s, prior to the front passing through. Then as the lower level flow shifts more easterly tonight, and a mid level trough advances east from Colorado, rain should start toward 06z, but I did lower Pops a little until after 09z. The HRRR and RUC13 models hold off any rain until after 09z, while the NAM and GFS begin rain before 09z. It appears the south and southwestern zones of Grant, Stevens, Morton and Stanton counties may be dry-slotted early in the precip event, with the mid and upper wave coming in. The highest precipitation chances will be in the eastern half of our forecast area, and mainly after 09z. Precipitation chances for rain will increase to likely by 12z, and the southeast zones southeast of a line from Stafford to Edwards to Clark counties will have showers with isolated thunderstorms mentioned. The front will have advected north as a warm front by late Monday night, and there could be enough lift for some scattered convection. As far as temperatures tonight, winds and precip may hold temperatures up, ranging from the upper 30s in the Scott City and Syracuse areas, to the lower 50s in the Ashland to Saint John areas. Rainfall amounts are always challenging, with light precip starting prior to 06z, and more substantial rain between 06Z and 12Z. .LONG TERM...(Tuesday through Sunday) ISSUED AT 351 AM CST MON NOV 4 2013 The main focus continues to be on the day 2 and 3 synoptic trough that will create impacts for Kansas. The models including the GFS, ECMWF and WRF 40 KM all generally agree on the timing of strong warm air and including dew points, theta-e advection from surface to above the 850 mb level early Tuesday morning. The model data show broad isentropic lift across areas west of Dodge City to the Colorado line, around 12 UTC with MUCAPES on the order of 500-900 Joules/kg. The area of instability and lift will shift eastward during the day as the trough axis and deeper cold air move into eastern Colorado. As a result, the precipitation probabilities were increased to around 80 percent with the isentropic lift/warm air advection timeframe. Precipitation type will likely be rain, rain showers or a rain snow mix as well after the initial frontal boundary moves through southwest Kansas. The best chances for any snow will be across west central Kansas, say from Hays to Dighton and Syracuse, where thermal profiles are most supportive before frontogenetic response lifting become essentially zero. Widespread temperatures falling into the mid 20`s are likely Tuesday night and early Wednesday morning west of a Hays to Cimarron to Hugoton line. The remainder of the forecast period will bring a day or so of upper ridging around Thursday before another westerly fast moving intense upper shortwave crashes into the Central or Northern Plains Friday. Cool and cloudy conditions on Wednesday will change to sunny and warmer in the 50`s and maybe 60`s by Friday before the next wave contributes to slightly cooler conditions. && .AVIATION...(For the 12Z TAFS through 12Z Tuesday morning) ISSUED AT 545 AM CST MON NOV 4 2013 A COLD FRONT PASSED THROUGH WESTERN KANSAS EARLY THIS MORNING, WITH WINDS TURNING NORTH AT 15G20KT BEHIND THE FRONT. AS THE DAY PROGRESSES, WINDS WILL SHIFT TO THE NORTHEAST AT AROUND 10 KNOTS. THIS EVENING, A MID LEVEL DECK AROUND BKN080 WILL MOVE IN FROM THE NORTHEAST, AND AS LOW LEVEL FLOW TURNS EAST, AND UPSLOPE AFFECT WILL DEVELOP. THERE IS A FAIRLY SHARP UPPER TROUGH WHICH WILL ADVECT INTO WESTERN KANSAS OVERNIGHT, AND RAIN WILL FORM TOWARD 08 TO 10Z. IFR CIGS WILL BE ASSOCIATED WITH THE LIGHT RAIN, AND WILL LIKELY DETERIORATE AFTER 12Z TUESDAY. && .PRELIMINARY POINT TEMPS/POPS... DDC 59 46 62 30 / 0 90 90 70 GCK 58 43 57 25 / 0 80 80 60 EHA 57 40 61 28 / 10 90 90 70 LBL 60 46 62 30 / 10 90 90 80 HYS 60 42 56 28 / 0 60 90 50 P28 66 52 63 36 / 10 70 80 90 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...Burke LONG TERM...Russell AVIATION...Burke
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
356 AM CST Mon Nov 4 2013 ...LONG TERM UPDATE... .SHORT TERM...(Today and tonight) ISSUED AT 230 AM CST MON NOV 4 2013 Today will see a cold front sweep through rather quickly and early from the northwest to the southeast. For much of the day, mostly sunny skies will prevail and winds will be northeast at 10 to 20 mph and gusty. This will allow temperatures to start to warm up early, but level off and stabilize in the mid 50s in the northwest, such as from Johnson City to Wakeeney. Temperatures in the Pratt, Barber, and Comanche county areas will top out in the mid 60s, prior to the front passing through. Then as the lower level flow shifts more easterly tonight, and a mid level trough advances east from Colorado, rain should start toward 06z, but I did lower Pops a little until after 09z. The HRRR and RUC13 models hold off any rain until after 09z, while the NAM and GFS begin rain before 09z. It appears the south and southwestern zones of Grant, Stevens, Morton and Stanton counties may be dry-slotted early in the precip event, with the mid and upper wave coming in. The highest precipitation chances will be in the eastern half of our forecast area, and mainly after 09z. Precipitation chances for rain will increase to likely by 12z, and the southeast zones southeast of a line from Stafford to Edwards to Clark counties will have showers with isolated thunderstorms mentioned. The front will have advected north as a warm front by late Monday night, and there could be enough lift for some scattered convection. As far as temperatures tonight, winds and precip may hold temperatures up, ranging from the upper 30s in the Scott City and Syracuse areas, to the lower 50s in the Ashland to Saint John areas. Rainfall amounts are always challenging, with light precip starting prior to 06z, and more substantial rain between 06Z and 12Z. .LONG TERM...(Tuesday through Sunday) ISSUED AT 351 AM CST MON NOV 4 2013 The main focus continues to be on the day 2 and 3 synoptic trough that will create impacts for Kansas. The models including the GFS, ECMWF and WRF 40 KM all generally agree on the timing of strong warm air and including dew points, theta-e advection from surface to above the 850 mb level early Tuesday morning. The model data show broad isentropic lift across areas west of Dodge City to the Colorado line, around 12 UTC with MUCAPES on the order of 500-900 Joules/kg. The area of instability and lift will shift eastward during the day as the trough axis and deeper cold air move into eastern Colorado. As a result, the precipitation probabilities were increased to around 80 percent with the isentropic lift/warm air advection timeframe. Precipitation type will likely be rain, rain showers or a rain snow mix as well after the initial frontal boundary moves through southwest Kansas. The best chances for any snow will be across west central Kansas, say from Hays to Dighton and Syracuse, where thermal profiles are most supportive before frontogenetic response lifting become essentially zero. Widespread temperatures falling into the mid 20`s are likely Tuesday night and early Wednesday morning west of a Hays to Cimarron to Hugoton line. The remainder of the forecast period will bring a day or so of upper ridging around Thursday before another westerly fast moving intense upper shortwave crashes into the Central or Northern Plains Friday. Cool and cloudy conditions on Wednesday will change to sunny and warmer in the 50`s and maybe 60`s by Friday before the next wave contributes to slightly cooler conditions. && .AVIATION...(For the 06Z TAFS through 06Z Monday night) ISSUED AT 1201 AM CST MON NOV 4 2013 For the most part, VFR and breezy conditions should be expected. Winds will south at 20g28kt prior to a cold front plowing through. a cold front will move southeastward through the terminal areas tonight, shifting winds to the north around 10 to 12z. Toward 12z on Tuesday, some light rain and cigs in the bkn to ovc 040 range will develop as cold air and moisture advects in. && .PRELIMINARY POINT TEMPS/POPS... DDC 59 46 62 30 / 0 90 90 70 GCK 58 43 57 25 / 0 80 80 60 EHA 57 40 61 28 / 10 90 90 70 LBL 60 46 62 30 / 10 90 90 80 HYS 60 42 56 28 / 0 60 90 50 P28 66 52 63 36 / 10 70 80 90 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...Burke LONG TERM...Russell AVIATION...Burke
AREA FORECAST DISCUSSION
NWS GOODLAND KS
241 AM MST MON NOV 4 2013 .UPDATE... ISSUED AT 520 PM MST SUN NOV 3 2013 WIND ADVISORY AND RED FLAG WARNING ALLOWED TO EXPIRE ON TIME. NO OTHER CHANGES MADE AT PRESENT TIME. && .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 108 PM MST SUN NOV 3 2013 LATEST WV IMAGERY AND RAP ANALYSIS SHOW RIDGE OVER MISSISSIPPI RIVER VALLEY AND TROUGH ACROSS ROCKIES. SEVERAL SHORTWAVE TROUGHS HAVE EJECTED OUT AHEAD OF THE MAIN UPPER TROUGH AXIS OVER THE SOUTHERN ROCKIES AND ANOTHER OVER THE NORTHERN PLAINS. SURFACE ANALYSIS SHOWS A 996MB TROUGH EXTENDING FROM KDEN TO KGLD WITH TIGHT GRADIENT IN PLACE OVER THE SOUTHEASTERN PART OF OUR CWA. IR/VIS SATELLITE SHOWS THIN LAYER OF STRADIVARIUS WITH LARGE BREAKS IN THE CLOUD LAYER ACROSS MUCH OF OUR CWA. THIS AFTERNOON...MIXING HAS BEEN MUCH BETTER FURTHER NORTH WITH CLOUDS HAVING LITTLE IMPACT AND SURFACE TROUGH AXIS JUST RECENTLY BEGINNING TO SHIFT SOUTH AND EAST (APPARENT AS FINE LINE ON RECENT RADAR MOVING SOUTH). BREEZY WINDS HAVE EXTENDED AS FAR NORTHWEST AS I-70 CORRIDOR IN EASTERN COLORADO...AND TEMPS HAVE ALSO WARMED INTO THE LOW 70S AT BOTH KGLD AND KITR. WHILE RH VALUES HAVE DROPPED TO WITHIN RFW CRITERIA IN SHERMAN/KIT CARSON COUNTY...TD VALUES HAVE ALREADY INCREASED BEHIND SURFACE TROUGH...AND THIS TREND SHOULD CONTINUE...SO 3HR REQUIREMENT FOR WIND/RH WILL LIKELY NOT BE MET IN THESE COUNTIES. WIND ADVISORY IS ON TRACK WITH GUSTS IN 45-49 MPH RANGE REPORTED OUTSIDE OF GOVE KANSAS AND HILL CITY. SIMILAR CONDITIONS ALOFT MAY BE OCCURRING OVER NORTON/EASTERN LOGAN COUNTIES...HOWEVER SURFACE OBS HAVE YET TO SUPPORT EXPANDING CURRENT ADVISORY. IN THE NEAR TERM I WILL NEED TO CONTINUE TO MONITOR FOR POSSIBLE EXPANSION OF WIND ADVISORY AND RFW...HOWEVER AT THIS POINT IT LOOKS LIKE WINDS SHOULD BEGIN TO DIMINISH ON TIME AS SURFACE TROUGH SHIFTS SOUTH. TONIGHT...COLD FRONT WILL DROP SOUTH WITH DECENT MID LEVEL MOISTURE AND VERY GOOD LARGE SCALE ASCENT OVER THE NW PART OF THE CWA. I CONSIDERED ADDING SPRINKLES OR LIGHT SHOWERS AROUND 06Z...HOWEVER MODELS CONTINUE TO ADVERTISE A DEEP SUB CLOUD DRY LAYER...SO CONFIDENCE IS LOW IN ANYTHING MORE THAN VIRGA AT THIS TIME. BEHIND THIS COLD FRONT WINDS WILL SHIFT TO THE NORTHWEST WITH A SHARP INCREASE IN WIND SPEED IMMEDIATELY BEHIND THE FRONT. 12Z NAM/GFS BOTH SHOW BL WINDS AROUND 30-35KT AND H85 WINDS 45-50KTS. IT WILL BE HARD TO MIX THE STRONGEST WINDS TO THE SURFACE AFTER SUNSET...HOWEVER WE COULD SEE A BRIEF PERIOD OF ADVISORY LEVEL WINDS TRANSLATING FROM THE NW TO THE SE FROM 06Z-12Z. I INCREASED WINDS TO INCLUDE WINDY WORDING...HOWEVER DUE TO THE MARGINAL CONDITIONS AND BRIEF NATURE I DECIDED AGAINST ISSUING AN ADVISORY. MONDAY...WITH COLD FRONT FURTHER SOUTH WE SHOULD BE ANYWHERE FROM 10F TO 20F DEGREES COOLER (UPPER 40S NW TO UPPER 50S SE). SHORTWAVE RIDGE BETWEEN EXITING SHORTWAVE AND NEXT SYSTEM WILL BE IN PLACE THROUGH MOST OF THE DAY...SO WITH DRY/SUBSIDENT AIR MASS OVERHEAD I EXPECT DRY CONDITIONS THROUGH MONDAY AFTERNOON. SURFACE GRADIENT AND WINDS ALOFT WILL DECREASE THROUGH MONDAY MORNING...SO IT LOOKS LIKE WE WILL HAVE A REPRIEVE FROM BREEZY/WINDY CONDITIONS BY MIDDAY. .LONG TERM...(THURSDAY THROUGH SUNDAY) ISSUED AT 241 AM MST MON NOV 4 2013 FOR THE EXTENDED FORECAST...A BRIEF PERIOD OF SHORTWAVE RIDGING ON THURSDAY PRECEDES ANOTHER VIGOROUS SHORTWAVE TROUGH PASSING THROUGH THE HIGH PLAINS ON FRIDAY. THE CANADIAN AND EUROPEAN MODELS CONTINUE TO BE THE MOST AGGRESSIVE WITH THE STRENGTH OF THIS TROUGH. THE GFS IS NOW SHOWING A SLIGHTLY STRONGER SHORTWAVE THAN IT WAS FOR THE 00Z RUN YESTERDAY WHEN IT WAS DEPICTING ZONAL FLOW. MOST OF THE AVAILABLE GUIDANCE SUGGESTS THAT ANY PRECIPITATION WITH THIS SYSTEM WILL STAY WELL TO THE NORTH...CLOSER TO THE SURFACE LOW THAT DEVELOPS AHEAD OF THE SHORTWAVE. THE CANADIAN SUGGESTS SOME PRECIPITATION DEVELOPING OVER NORTH CENTRAL COLORADO AND MOVING IN DURING THE AFTERNOON TO EVENING HOURS FRIDAY. LOOKING AT MODEL SOUNDINGS...THINK THE AIRMASS IS TOO DRY IN THE LOWER LEVELS TO JUSTIFY PLACING PRECIP CHANCES INTO THE FORECAST FOR THE TIME BEING. ONCE THE SHORTWAVE PASSES...ZONAL FLOW OR WEAK RIDGING BECOMES THE PREDOMINANT WEATHER PATTERN. THIS MEANS A CONTINUATION OF THE DRY WEATHER FOR THE FORECAST AREA. TEMPERATURES FOR THE EXTENDED FORECAST SHOULD BE QUITE CONSISTENT THROUGHOUT THE PERIOD. THE SHORTWAVE TROUGH THAT CROSSES THE HIGH PLAINS ON FRIDAY MAY FORCE A COLD FRONT DOWN THROUGH THE AREA. MODELS DISAGREE ON THE EXTENT OF COOLING BEHIND THIS FRONT SO HAVE ONLY MADE A SLIGHT ADJUSTMENT DOWNWARD ON SATURDAY FOR MAINLY NORTHERN PORTIONS OF THE REGION. OTHER THAN THAT...TEMPERATURES SHOULD BE AROUND NORMAL THROUGHOUT THE EXTENDED FORECAST WITH THE POSSIBILITY OF ABOVE NORMAL TEMPERATURES ON FRIDAY AND THEN AGAIN THE START OF NEXT WEEK. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 1000 PM MST SUN NOV 3 2013 FOR KGLD AND KMCK...VFR CONDITIONS EXPECTED THROUGH MUCH OF THE TAF PERIOD. A WEATHER SYSTEM WILL MOVE ACROSS BOTH TERMINALS EARLY MONDAY MORNING BRINGING SCT TO POSSIBLY BKN CIGS AROUND 2500FT FROM 08Z-15Z OR SO. THIS IS A PRETTY BIG CHANGE FROM 00Z GUIDANCE SO FOR NOW KEPT CIGS VFR BUT HINTED AT MVFR POSSIBILITY. OTHERWISE FOR EARLY THIS MORNING NORTHWEST WINDS GUSTING 25-30KTS POSSIBLE BEFORE SUNRISE. FOR THE REST OF THE TAF PERIOD SFC HIGH MOVES IN BY LATE MORNING/EARLY AFTERNOON WITH WINDS SLOWLY VEERING FROM NORTHWEST TO EAST AT SPEEDS UNDER 10KTS. CLOUDINESS LIMITED TO CIRRUS LEVEL. TOWARD THE END OF THE TAF PERIOD CIGS WILL SLOWLY DECREASE BUT REMAIN VFR AS ANOTHER WEATHER SYSTEM APPROACHES THE AREA. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ UPDATE...99 SHORT TERM...DR LONG TERM...RRH AVIATION...99
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
237 AM CST Mon Nov 4 2013 ...Updated for the short term discussion... .SHORT TERM...(Today and tonight) ISSUED AT 230 AM CST MON NOV 4 2013 Today will see a cold front sweep through rather quickly and early from the northwest to the southeast. For much of the day, mostly sunny skies will prevail and winds will be northeast at 10 to 20 mph and gusty. This will allow temperatures to start to warm up early, but level off and stabilize in the mid 50s in the northwest, such as from Johnson City to Wakeeney. Temperatures in the Pratt, Barber, and Comanche county areas will top out in the mid 60s, prior to the front passing through. Then as the lower level flow shifts more easterly tonight, and a mid level trough advances east from Colorado, rain should start toward 06z, but I did lower Pops a little until after 09z. The HRRR and RUC13 models hold off any rain until after 09z, while the NAM and GFS begin rain before 09z. It appears the south and southwestern zones of Grant, Stevens, Morton and Stanton counties may be dry-slotted early in the precip event, with the mid and upper wave coming in. The highest precipitation chances will be in the eastern half of our forecast area, and mainly after 09z. Precipitation chances for rain will increase to likely by 12z, and the southeast zones southeast of a line from Stafford to Edwards to Clark counties will have showers with isolated thunderstorms mentioned. The front will have advected north as a warm front by late Monday night, and there could be enough lift for some scattered convection. As far as temperatures tonight, winds and precip may hold temperatures up, ranging from the upper 30s in the Scott City and Syracuse areas, to the lower 50s in the Ashland to Saint John areas. Rainfall amounts are always challenging, with light precip starting prior to 06z, and more substantial rain between 06Z and 12Z. .LONG TERM...(Monday night through Sunday) ISSUED AT 245 PM CST SUN NOV 3 2013 A large upper level open wave trough is anticipated to move into the western CONUS Monday then into the Rockies and High Plains Tuesday. This system will then eject northeastward into the remainder of the Plains and Mississippi Valley on Wednesday. As this system approaches, mid levels of the atmosphere will become saturated allowing for cloudy skies to envelop western Kansas by Monday night. Isolated thunderstorms will become possible after midnight, mainly across central Kansas as well as northern Kansas where the best lift will be observed. An area of low pressure at the surface will intensify across northeastern New Mexico Monday night then shift eastward across the Texas and Oklahoma Tuesday. An associated frontal boundary will be positioned across western Kansas during the afternoon and this is where rain showers and isolated thunderstorms will be possible. The low and frontal boundary shift eastward Tuesday night with the chance of wrap around showers continuing across western Kansas. Temperatures will fall rapidly behind this front and some places could see snow or a mix of rain and snow after midnight. Strong northerly winds will also be felt behind this front making it feel cooler than it actually is. The system then moves out of the area by sunrise Wednesday with decreasing cloudiness from west to east. As for temperatures, lows Tuesday morning are forecasted to range from the upper 30s across west central Kansas to lower 50s across south central Kansas where increased dewpoints will be found. In fact, temperatures could start rising after midnight across south central Kansas due to the increased moisture. A wide range of temperatures are expected Tuesday afternoon due to the position of the aforementioned front with highs ranging from the mid 40s across west central Kansas to around 60 degrees across portions of the KS/OK border and south central Kansas. Lows behind this front Wednesday morning are anticipated to range from the upper 20s across west central Kansas to upper 30s across south Central Kansas. Highs Wednesday afternoon should reach to around 50 degrees. Tranquil weather is then expected Wednesday night through Saturday with partly cloudy skies and dry conditions. This is due to a weak upper level ridge positioned south of the CWA. Models are suggesting an upper level shortwave to move through the Northern Plains Friday into Saturday but the atmosphere above the Central High plains should be dry enough that only a slight increase in clouds and a wind shift could be observed. Highs Thursday through Saturday will generally range from the mid 50s to mid 60s with lows in the 30s. && .AVIATION...(For the 06Z TAFS through 06Z Monday night) ISSUED AT 1201 AM CST MON NOV 4 2013 For the most part, VFR and breezy conditions should be expected. Winds will south at 20g28kt prior to a cold front plowing through. a cold front will move southeastward through the terminal areas tonight, shifting winds to the north around 10 to 12z. Toward 12z on Tuesday, some light rain and cigs in the bkn to ovc 040 range will develop as cold air and moisture advects in. && .PRELIMINARY POINT TEMPS/POPS... DDC 59 46 62 30 / 0 90 90 70 GCK 58 43 57 25 / 0 80 80 60 EHA 57 40 61 28 / 10 90 90 70 LBL 60 46 62 30 / 10 90 90 80 HYS 60 42 56 28 / 0 60 90 50 P28 66 52 63 36 / 10 70 80 90 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...Burke LONG TERM...Hovorka_42 AVIATION...Burke
AREA FORECAST DISCUSSION
NWS TOPEKA KS
1126 PM CST Sun Nov 3 2013 ...Update to aviation forecast discussion... .SHORT TERM...(This Evening through Monday) Issued at 213 PM CST SUN NOV 3 2013 Water vapor imagery this afternoon continues to show a stream of embedded shortwave troughs rotating through the main wave positioned across the western conus. The southwesterly flow has allowed ample mid level moisture from the western coast to trail northeast across the central plains, resulting in a mid level deck of scattered to broken cloud cover this afternoon. This cloud cover however has not hindered the strong southerly winds continuing to gust to around 45 mph near the Concordia and Abilene areas, lessening between 30 and 40 mph gusts near the Manhattan and Topeka areas. Will continue with the current wind advisory through 6 PM when winds weaken below criteria. The surface trough responsible for the tight pressure gradient should shift slightly eastward into western Kansas this evening as a progressive upper shortwave trough lifts northeast through the northern plains. This should keep the gusty winds in place overnight, weakening slightly between 15 and 20 mph sustained with gusts up to 30 mph. Combined with cloud cover in the area, lows in the upper 40s will be common. In terms of precipitation, very weak echos develop per the 4 km ARW and 3 km HRRR for late this evening into the overnight hours. The NAM also hints at weak isentropic lift on the 310 and 315K surfaces as an area of weak mid level vorticity is noted across eastern areas of Kansas. The limiting factors are the lack of strong mid level forcing and dry air at the low levels with cloud bases near 10 KFT. Kept slight chances for any developing shower just in case it is able to overcome the drier air and reach the surface. Another warm Monday afternoon is in store as the weak cold front tracks southeast, weakening winds to around 10 mph along and behind the boundary. Surface high pressure builds in bringing weak cold advection into the area. Have trended highs toward 60 degrees for north central areas, warming to the lower and middle 60s for east central Kansas as southerly winds around 15 mph are maintained through mid afternoon when the boundary arrives. Conditions remain dry through the afternoon as a strong shortwave trough deepens out west, bringing increasing rain chances by Monday evening. .LONG TERM...(Monday Night through Sunday) Issued at 213 PM CST SUN NOV 3 2013 Overnight Monday night into Tuesday morning the pattern sets up for a rainy early/mid week. By 12z Tuesday, the inverted surface trof has set up along the central and northern portions of the cwa while tropical moisture is swept northward over the central plains. Rain showers expected to lift into the southern counties in the evening and spread into Nebraska by sunrise. Not much instability to work with throughout this entire system progression, and will only carry isolated thunder as a result. Of interest is PW values which come in at 1 to near 1.5 inches by 12z Tuesday which is about 180% of normal for this time of year. Without a specific boundary or focusing mechanism in the cwa on Tuesday would anticipate the moisture and ascent to bring a broad area of moderate rain throughout the day, before the cold front associated with the upper trof sweeps through in the overnight hours. May see some pockets of heavier rain as the front moves through, but have gone with generally 1-1.5 inches across the area from evening Tuesday through Wednesday morning. EC has come in not quite as cold at 850mb as the trof passes and also not as far south. Cold temps already lagged behind the moisture and will therefore keep mention of any snow mixed in with the rain out of the forecast. Will have to see how the cold pool moves across the northern counties on Wednesday morning into afternoon as it could be cold/unstable enough to generate a few flakes. Also will expect falling temperatures on Wednesday afternoon as colder air comes in. Highs in the 50s on a rainy Tuesday afternoon will become a dry breezy 40s for Wednesday. Fortunately temperatures warm up slowly through the end of the week as zonal flow aloft returns Thursday and the lee trof/southerly surface winds return on Friday. GFS and EC differ with the strength of the shortwave that slides across the northern plains later Friday into Saturday, but with northern track have kept the warmer drier trend at this time with highs in the 50s. && .AVIATION...(For the 06Z TAFs through 06Z Monday Night) Issued at 1125 PM CST SUN NOV 3 2013 Winds will continue to be the main concern through 15Z Monday as south winds around 15 kts with gusts to 25kt will prevail ahead of an approaching low pressure and cold front. The front is expected to move through MHK by 17Z and TOP and FOE around 19Z. Winds will shift to the west then north through 23Z and decrease to less than 10 kts. Sprinkles or light showers may move near TOP and FOE through 10Z. && .TOP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...Bowen LONG TERM...67 AVIATION...53
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1000 PM MST SUN NOV 3 2013 .UPDATE... ISSUED AT 520 PM MST SUN NOV 3 2013 WIND ADVISORY AND RED FLAG WARNING ALLOWED TO EXPIRE ON TIME. NO OTHER CHANGES MADE AT PRESENT TIME. && .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 108 PM MST SUN NOV 3 2013 LATEST WV IMAGERY AND RAP ANALYSIS SHOW RIDGE OVER MISSISSIPPI RIVER VALLEY AND TROUGH ACROSS ROCKIES. SEVERAL SHORTWAVE TROUGHS HAVE EJECTED OUT AHEAD OF THE MAIN UPPER TROUGH AXIS OVER THE SOUTHERN ROCKIES AND ANOTHER OVER THE NORTHERN PLAINS. SURFACE ANALYSIS SHOWS A 996MB TROUGH EXTENDING FROM KDEN TO KGLD WITH TIGHT GRADIENT IN PLACE OVER THE SOUTHEASTERN PART OF OUR CWA. IR/VIS SATELLITE SHOWS THIN LAYER OF STRADIVARIUS WITH LARGE BREAKS IN THE CLOUD LAYER ACROSS MUCH OF OUR CWA. THIS AFTERNOON...MIXING HAS BEEN MUCH BETTER FURTHER NORTH WITH CLOUDS HAVING LITTLE IMPACT AND SURFACE TROUGH AXIS JUST RECENTLY BEGINNING TO SHIFT SOUTH AND EAST (APPARENT AS FINE LINE ON RECENT RADAR MOVING SOUTH). BREEZY WINDS HAVE EXTENDED AS FAR NORTHWEST AS I-70 CORRIDOR IN EASTERN COLORADO...AND TEMPS HAVE ALSO WARMED INTO THE LOW 70S AT BOTH KGLD AND KITR. WHILE RH VALUES HAVE DROPPED TO WITHIN RFW CRITERIA IN SHERMAN/KIT CARSON COUNTY...TD VALUES HAVE ALREADY INCREASED BEHIND SURFACE TROUGH...AND THIS TREND SHOULD CONTINUE...SO 3HR REQUIREMENT FOR WIND/RH WILL LIKELY NOT BE MET IN THESE COUNTIES. WIND ADVISORY IS ON TRACK WITH GUSTS IN 45-49 MPH RANGE REPORTED OUTSIDE OF GOVE KANSAS AND HILL CITY. SIMILAR CONDITIONS ALOFT MAY BE OCCURRING OVER NORTON/EASTERN LOGAN COUNTIES...HOWEVER SURFACE OBS HAVE YET TO SUPPORT EXPANDING CURRENT ADVISORY. IN THE NEAR TERM I WILL NEED TO CONTINUE TO MONITOR FOR POSSIBLE EXPANSION OF WIND ADVISORY AND RFW...HOWEVER AT THIS POINT IT LOOKS LIKE WINDS SHOULD BEGIN TO DIMINISH ON TIME AS SURFACE TROUGH SHIFTS SOUTH. TONIGHT...COLD FRONT WILL DROP SOUTH WITH DECENT MID LEVEL MOISTURE AND VERY GOOD LARGE SCALE ASCENT OVER THE NW PART OF THE CWA. I CONSIDERED ADDING SPRINKLES OR LIGHT SHOWERS AROUND 06Z...HOWEVER MODELS CONTINUE TO ADVERTISE A DEEP SUB CLOUD DRY LAYER...SO CONFIDENCE IS LOW IN ANYTHING MORE THAN VIRGA AT THIS TIME. BEHIND THIS COLD FRONT WINDS WILL SHIFT TO THE NORTHWEST WITH A SHARP INCREASE IN WIND SPEED IMMEDIATELY BEHIND THE FRONT. 12Z NAM/GFS BOTH SHOW BL WINDS AROUND 30-35KT AND H85 WINDS 45-50KTS. IT WILL BE HARD TO MIX THE STRONGEST WINDS TO THE SURFACE AFTER SUNSET...HOWEVER WE COULD SEE A BRIEF PERIOD OF ADVISORY LEVEL WINDS TRANSLATING FROM THE NW TO THE SE FROM 06Z-12Z. I INCREASED WINDS TO INCLUDE WINDY WORDING...HOWEVER DUE TO THE MARGINAL CONDITIONS AND BRIEF NATURE I DECIDED AGAINST ISSUING AN ADVISORY. MONDAY...WITH COLD FRONT FURTHER SOUTH WE SHOULD BE ANYWHERE FROM 10F TO 20F DEGREES COOLER (UPPER 40S NW TO UPPER 50S SE). SHORTWAVE RIDGE BETWEEN EXITING SHORTWAVE AND NEXT SYSTEM WILL BE IN PLACE THROUGH MOST OF THE DAY...SO WITH DRY/SUBSIDENT AIR MASS OVERHEAD I EXPECT DRY CONDITIONS THROUGH MONDAY AFTERNOON. SURFACE GRADIENT AND WINDS ALOFT WILL DECREASE THROUGH MONDAY MORNING...SO IT LOOKS LIKE WE WILL HAVE A REPRIEVE FROM BREEZY/WINDY CONDITIONS BY MIDDAY. .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 207 PM MST SUN NOV 3 2013 MONDAY NIGHT-WEDNESDAY...PRIMARY FORECAST CONCERN WILL CONTINUE TO FOCUS ON STORM SYSTEM EXPECTED TO IMPACT THE CWA THROUGH TUESDAY EVENING. MODELS REMAIN IN REASONABLE AGREEMENT WITH LARGE SCALE UPPER LEVEL FEATURES WITH APPROACHING SYSTEM...ALTHOUGH STILL REMAINS A LARGE DEGREE OF VARIANCE WITH RESPECT TO NORTHWARD PLACEMENT OF WARMER AIR MASS...WHICH WILL PLAY A CRITICAL ROLE IN PTYPE FORECAST AND RESULTING SNOW AMOUNTS. OVERALL...A FEW MODELS SEEM TO BE JUMPING BETWEEN COOLER SOLUTIONS ON 00Z CYCLES AND WARMER VALUES AT 12Z (ESPECIALLY GEM). DESPITE THE VARIANCES IN IN THE INDIVIDUAL RUNS BOTH THE SREF MEAN AND CONSENSUS DATABASE REMAIN FAIRLY CONSISTENT IN THE OVERALL TEMPERATURE VALUES. AS SHORT WAVE TROUGH APPROACHES THE AREA EXPECT STRONG MOISTURE ADVECTION TO DEVELOP AHEAD OF IT...WITH ISENTROPIC SURFACES AROUND H7 CLIMBING TO AROUND 5 G/KG ON 295 K SURFACE BY 12Z TUESDAY. THIS AREA OF MOISTURE ADVECTION LOOKS TO FEED INTO AREA OF PERSISTENT FRONTOGENESIS CENTERED AROUND H7. WITH EXPECTED FORCING AND MOISTURE LINING UP WITH AREA OF POTENTIAL INSTABILITY (PER MUCAPE AND THETA E LAPSE RATES) EXPECT A FAIRLY VIGOROUS AND SOMEWHAT PERSISTENT BAND ACROSS NORTHERN CWA ON TUESDAY MORNING BEFORE FRONT BEGINS TO MOVE SOUTH ACROSS THE AREA AS SYSTEM DEPARTS DURING THE AFTERNOON AND EVENING. IF PRECIPITATION WOULD TO OCCUR AS ALL SNOW...SIGNIFICANT AMOUNTS WOULD BE POSSIBLE ACROSS THE NORTH...BUT LATEST DATA CONTINUES TO SUPPORT THAT PRECIP WILL REMAIN RAIN OR A RA/SN MIX FOR SOME TIME ON TUESDAY AND POSSIBLY NOT CHANGE OVER COMPLETELY BY THE AFTERNOON. WHILE MODEL TRENDS ARE CERTAINLY NOT ENCOURAGING FOR HIGH SNOW AMOUNTS...HAVE SOME CONCERNS THAT AGEOSTROPHIC RESPONSE TO NEARBY JET STREAKS WOULD ENHANCE A SOUTHERLY PUSH OF COOLER TEMPS SO DO NOT WANT TO TOTALLY DOWNPLAY SNOW AMOUNTS IN THE NORTHWESTERN CWA JUST YET AND WILL KEEP AREA OF 2 TO 4 INCHES IN THIS LOCATION. OTHERWISE...STRONG SUBSIDENCE WILL OVERSPREAD THE AREA BEHIND THE DEPARTING TROUGH BRINGING A PERIOD OF DRY AND WARMER WEATHER THROUGH THE MIDDLE OF THE WEEK. IN THE EXTENDED (WED NIGHT-SUNDAY)...MEDIUM RANGE MODELS HAVE COME INTO BETTER AGREEMENT DURING THE EXTENDING PERIOD WITH DECENT AGREEMENT IN BRINGING A SHORT WAVE TROUGH ACROSS THE PLAINS ON FRIDAY FOLLOWED BY A PERIOD OF SHORT WAVE RIDGING. WITH GEFS ENSEMBLE AND OPERATIONAL MODELS INDICATING A DRY PASSAGE OF THIS TROUGH AND THE AFOREMENTIONED RIDGING DOES NOT LOOK LIKE ANY GREAT PRECIP POSSIBILITIES ARE EXPECTED THIS WEEK. OTHERWISE WITH DECENT MODEL AGREEMENT SEE LITTLE REASON FOR DIVERGING FROM CONSENSUS FIELDS ASIDE FROM ADJUSTING GRIDS TO LINE UP BETTER WITH VARIOUS ERRORS AND BIASES OVER THE PAST FEW WEEKS. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 1000 PM MST SUN NOV 3 2013 FOR KGLD AND KMCK...VFR CONDITIONS EXPECTED THROUGH MUCH OF THE TAF PERIOD. A WEATHER SYSTEM WILL MOVE ACROSS BOTH TERMINALS EARLY MONDAY MORNING BRINGING SCT TO POSSIBLY BKN CIGS AROUND 2500FT FROM 08Z-15Z OR SO. THIS IS A PRETTY BIG CHANGE FROM 00Z GUIDANCE SO FOR NOW KEPT CIGS VFR BUT HINTED AT MVFR POSSIBILITY. OTHERWISE FOR EARLY THIS MORNING NORTHWEST WINDS GUSTING 25-30KTS POSSIBLE BEFORE SUNRISE. FOR THE REST OF THE TAF PERIOD SFC HIGH MOVES IN BY LATE MORNING/EARLY AFTERNOON WITH WINDS SLOWLY VEERING FROM NORTHWEST TO EAST AT SPEEDS UNDER 10KTS. CLOUDINESS LIMITED TO CIRRUS LEVEL. TOWARD THE END OF THE TAF PERIOD CIGS WILL SLOWLY DECREASE BUT REMAIN VFR AS ANOTHER WEATHER SYSTEM APPROACHES THE AREA. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ UPDATE...99 SHORT TERM...DR LONG TERM...JRM AVIATION...99
AREA FORECAST DISCUSSION
NWS NEW ORLEANS LA
344 PM CST MON NOV 4 2013 .DISCUSSION...QUIET DAY OVERALL BUT THERE WAS AN INTERESTING LITTLE FEATURE OVER THE CWA TODAY. IF YOU NOTICED IT ACROSS THE NORTH AND SOUTH SHORES OR HAPPENED TO SEE IT ON SATELLITE THERE WAS THE IMMEDIATE/SHARP CLEARING LINE IN THE CLOUDS. THESE LOW CLOUDS WERE AROUND 4500-5K FT HIGH AND THE CLEARING LINE MOVED FROM WEST TO EAST. OVERALL IT WAS DIFFICULT TO SAY WHAT WAS CAUSING THIS BUT LOOKING AT THE RUC13 THE 295K LEVEL THERE WAS A NOTICEABLE RISE IN THETA SFC EAST OF 55. MOISTURE WAS TRAPPED UNDER IT AND THUS LOW CLOUDS STAYED IN THROUGH A GOOD PORTION OF THE DAY. WEST OF 55 THE THETA SFC WERE FALLING AND FALLING QUICKLY SUGGESTING SUBSIDENCE AND MIXING AND THUS CLEARING SKIES. OVER THE NEXT 36 HRS THE WEATHER WILL GENERALLY BE QUIET BUT CANT RULE OUT A FEW LIGHT SHRA OR SPRINKLES. RAIN CHANCES INCREASE LATE WED AND ESPECIALLY WED NIGHT AS A COLD FRONT MOVES THROUGH. THE AIRMASS IS STILL RECOVERING WITH 12Z PWS STILL NEAR 0.50" AND MOISTURE HAS BEEN INCREASING THROUGH THE DAY AND WILL CONTINUE THROUGH TOMORROW BUT DEEP MOISTURE WILL NOT BE IN PLACE UNTIL WED AFTN. AN ALREADY AMPLIFIED PATTERN OVER THE CONUS WILL AMPLIFY A TAD MORE OVERNIGHT. THE RIDGE WILL REMAIN IN PLACE OF THE THE ERN GULF AND FL/EXTREME SERN CONUS WHILE THE H5 JET CORE STILL UP STREAM OF THE L/W TROUGH APPROACHING THE CONTINENTAL DIVIDE WILL CAUSE THE TROUGH TO DIG ABOUT ANOTHER 12 HRS. THIS WILL LEAD TO LEE SIDE CYCLOGENESIS TONIGHT AND THEN AS THE TROUGH STOPS DIGGING TOMORROW THE SFC LOW WILL THEN BEGIN TO DEEPEN AND LIFT ACROSS THE CNTRL PLAINS. A COLD FRONT WILL APPROACH THE ARKLATEX TUE NIGHT AND INTO THE LOWER MS VALLEY WED BUT THE FRONT WILL NOT MAKE IT THROUGH OUR REGION UNTIL WED NIGHT NIGHT. THIS IS DUE TO THE TROUGH AND SFC LOW BOTH QUICKLY LIFTING TO THE NE. WITH DEEPER MOISTURE FINALLY IN PLACE LATE WED ALONG WITH THE COLD FRONT APPROACHING AND TROUGH MOVING INTO THE CNTRL PLAINS RAIN CHANCE WILL INCREASE BUT IN ALL LIKELIHOOD THE RAIN WILL PROBABLY HOLD OFF TILL THE EVNG AND OVERNIGHT HRS. AS FOR STRONG/SVR CHANCES THERE WILL BE NO INSTABILITY TO WORK WITH. IN ADDITION THE BEST FORCING WILL REMAIN NORTH OF THE REGION AND EVEN MID LVL WINDS WILL NOT BE THAT IMPRESSIVE (MAYBE 40-45KTS AT BEST). RAIN WILL COME TO AN END AS THE COLD FRONT PUSHES THROUGH THE AREA OVERNIGHT WED/THU MORNING. ONCE THIS OCCURS DRIER AND COOLER AIR WILL WORK BACK INTO THE REGION. AFTER FRONTAL PASSAGE EARLY THU THE WEATHER WILL BE QUIET AND COOL ONCE AGAIN AND THROUGH THE WEEKEND. THE ENVIRONMENT IS EXPECTED TO DRY OUT WITH DEWPOINTS POSSIBLY DROPPING INTO THE 30S TO LOWER 40S BY FRI. ZONAL FLOW WILL ACTUALLY REMAIN OVER THE AREA THROUGH THE WEEKEND WITH HIGH PRESSURE DOMINATING AT THE SFC. BOTH LL TEMPS AND MOISTURE WILL SLOWLY MODERATE AND RECOVER THROUGH THE WEEKEND BUT OVERALL WE WILL REMAIN DRY. /CAB/ && .MARINE...TIGHTENING PRESSURE GRADIENT BETWEEN HIGH PRESSURE OVER EAST COAST AND DEVELOPING SFC LOW OVER SOUTHERN PLAINS IS LEADING TO A TIGHTENING OF THE PRESSURE GRADIENT OVER THE COASTAL WATERS. SMALL CRAFT ADVISORIES HAVE BEEN ISSUED FOR THE OPEN GULF WATERS THROUGH TUESDAY EVENING AND NOW THE SOUNDS AS WELL. THE ADVISORY WILL LIKELY NEED TO BE EXTENDED THROUGH AT LEAST TUESDAY NIGHT...AND POSSIBLY WEDNESDAY BEFORE THE GRADIENT RELAXES TEMPORARILY. FOR THE TIDAL LAKES...EXERCISE CAUTION HEADLINES ARE IN EFFECT TONIGHT...AND WILL LIKELY NEED TO BE EXTENDED OR POSSIBLY UPGRADED TO ADVISORIES FOR TUESDAY. CONDITIONS SHOULD IMPROVE BY WEDNESDAY AS THE GRADIENT EASES AHEAD OF A COLD FRONT THAT IS FORECAST TO MOVE ACROSS THE COASTAL WATERS WEDNESDAY NIGHT AND EARLY THURSDAY. SMALL CRAFT ADVISORY CONDITIONS ARE ONCE AGAIN FORECAST TO DEVELOP IN THE WAKE OF THIS FRONT DURING THE DAY THURSDAY AS STRONG OFFSHORE FLOW DEVELOPS. 95/CAB && .AVIATION...VFR CONDITIONS EXPECTED TO CONTINUE ACROSS THE AREA. A THINK LAYER OF CLOUDS AROUND 4KFT HAS BEEN TRACKING EAST ALL DAY AN NOW IS BEGINNING TO THIN. EXPECT THIS DECK TO NOT BE MUCH OF AN IMPACT WITHIN THE NEXT FEW HOURS. MID LEVEL CLOUDS WILL PREVAIL THROUGH THE PERIOD. EAST TO SOUTHEAST WINDS WILL NOT FALL OFF QUITE SO MUCH OVERNIGHT AND ARE EXPECTED TO BECOME STRONG AND GUSTY ON TUESDAY. /MEFFER/ && .DECISION SUPPORT... DSS CODE...BLUE. DEPLOYED...NONE. ACTIVATION...NONE. ACTIVITIES...SLURRY SUPPORT. DECISION SUPPORT SERVICES (DSS) CODE LEGEND GREEN = NO WEATHER IMPACTS THAT REQUIRE ACTION BLUE = LONG FUSED WATCH/WARNING/ADVISORY IN EFFECT OR HIGH VISIBILITY EVENT YELLOW = HEIGHTENED IMPACTS WITH SHORT FUSED WATCH/WARNING/ADVISORY ISSUANCES; RADAR SUPPORT ORANGE = HIGH IMPACTS - SLIGHT TO MODERATE RISK SEVERE; NEARBY TROPICAL EVENTS; HAZMAT OR OTHER LARGE EPISODES RED = FULL ENGAGEMENT FOR MODERATE TO HIGH RISK SVR AND/OR DIRECT TROPICAL THREATS; EVENTS OF NATIONAL SIGNIFICANCE && .PRELIMINARY POINT TEMPS/POPS... MCB 53 75 56 78 / 10 10 10 40 BTR 59 77 61 82 / 10 10 10 40 ASD 56 75 60 79 / 20 10 10 30 MSY 62 76 65 80 / 20 20 10 30 GPT 57 74 62 77 / 10 10 10 20 PQL 53 75 58 78 / 10 10 10 20 && .LIX WATCHES/WARNINGS/ADVISORIES... LA...NONE. GM...SMALL CRAFT ADVISORY UNTIL 6 PM TUESDAY FOR THE FOLLOWING ZONES: BRETON SOUND...CHANDELEUR SOUND...COASTAL WATERS FROM BOOTHVILLE LA TO THE SOUTHWEST PASS OF THE MISSISSIPPI RIVER OUT 20 NM...COASTAL WATERS FROM PASCAGOULA MS TO STAKE ISLAND LA FROM 20 TO 60 NM...COASTAL WATERS FROM PASCAGOULA MS TO STAKE ISLAND LA OUT 20 NM...COASTAL WATERS FROM PORT FOURCHON TO LOWER ATCHAFALAYA RIVER FROM 20 TO 60 NM...COASTAL WATERS FROM PORT FOURCHON TO LOWER ATCHAFALAYA RIVER OUT 20 NM...COASTAL WATERS FROM STAKE ISLAND LA TO THE SOUTHWEST PASS OF THE MISSISSIPPI RIVER FROM 20 TO 60 NM...COASTAL WATERS FROM THE SOUTHWEST PASS OF THE MISSISSIPPI RIVER TO PORT FOURCHON FROM 20 TO 60 NM...COASTAL WATERS FROM THE SOUTHWEST PASS OF THE MISSISSIPPI RIVER TO PORT FOURCHON OUT 20 NM...AND MISSISSIPPI SOUND. MS...NONE. GM...SMALL CRAFT ADVISORY UNTIL 6 PM TUESDAY FOR THE FOLLOWING ZONES: BRETON SOUND...CHANDELEUR SOUND...COASTAL WATERS FROM BOOTHVILLE LA TO THE SOUTHWEST PASS OF THE MISSISSIPPI RIVER OUT 20 NM...COASTAL WATERS FROM PASCAGOULA MS TO STAKE ISLAND LA FROM 20 TO 60 NM...COASTAL WATERS FROM PASCAGOULA MS TO STAKE ISLAND LA OUT 20 NM...COASTAL WATERS FROM PORT FOURCHON TO LOWER ATCHAFALAYA RIVER FROM 20 TO 60 NM...COASTAL WATERS FROM PORT FOURCHON TO LOWER ATCHAFALAYA RIVER OUT 20 NM...COASTAL WATERS FROM STAKE ISLAND LA TO THE SOUTHWEST PASS OF THE MISSISSIPPI RIVER FROM 20 TO 60 NM...COASTAL WATERS FROM THE SOUTHWEST PASS OF THE MISSISSIPPI RIVER TO PORT FOURCHON FROM 20 TO 60 NM...COASTAL WATERS FROM THE SOUTHWEST PASS OF THE MISSISSIPPI RIVER TO PORT FOURCHON OUT 20 NM...AND MISSISSIPPI SOUND. && $$ SHORT/LONG/MARINE: CAB AVIATION: MEFFER
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
335 PM EST MON NOV 4 2013 .SYNOPSIS... HIGH PRESSURE OVER THE NORTHEAST STATES TONIGHT WILL BEGIN TO SLOWLY DRIFT OFFSHORE TONIGHT THROUGH WEDNESDAY. A COLD FRONT WILL CROSS THE AREA LATE THURSDAY. HIGH PRESSURE RETURNS FRIDAY THROUGH THE WEEKEND. && .NEAR TERM /UNTIL 6 AM TUESDAY MORNING/... STRONG ~1038 SFC HIGH (+2 STD DEV) WILL CONTINUE TO RIDGE SWD INTO THE MID-ATLANTIC REGION LATE THIS AFTERNOON AND TONIGHT...USHERING CONTINENTAL POLAR AIR INTO THE REGION. TEMPS HAVE ONLY WARMED INTO THE UPPER 40S NW TO MID 50S SE (-1 TO -1.5 STD DEV). ALOFT...MID LEVEL RIDGE WILL AMPLIFY OVER THE ERN CONUS AS SUBTROPICAL HIGH PRESSURE BUILDS OFF THE SOUTHEAST COAST. PLUME OF ANOMALOUS MOISTURE VISIBLE ON WATER VAPOR STREAMING FROM NEAR THE SRN TIP OF THE BAJA (REMNANTS OF SONIA) INTO THE OH VALLEY WILL CONTINUE TO SPILL HIGH CLOUDS OVER THE TOP OF THE RIDGE INTO THE LOCAL AREA. MEANWHILE...NE FLOW (BREEZY NEAR THE COAST...DIMINISHING TONIGHT) WILL ADVECT LOW LEVEL MOISTURE /STRATO-CU OFF THE WRN ATLANTIC INTO THE SE...SPREADING WWD THRU TONIGHT. NO ACTIVITY VISIBLE ON RADAR...SO DO NOT ANTICIPATE ANY PRECIP OVER THE SE THIS EVENING. CLOUDS HAVE BEEN A LITTLE SLOWER TO SPREAD WWD THAN ANTICIPATED...SO OPTED TO LOWERS TEMPS A DEG OR TWO INLAND TONIGHT. LOW DEWPOINTS AND LIGHT WINDS WILL ALLOW TEMPS TO DROP INTO THE LOW-MID 30S INLAND TO THE LOW 40S ALONG THE COAST. && .SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY/... PER LATEST WATER VAPOR IMAGERY...NEXT WEATHER SYSTEM TAKING SHAPE OVER THE WRN CONUS. SPEED MAX WILL EMERGE ON THE ERN PERIPHERY...EJECTING THE TROUGH AND ATTENDANT COLD FRONT EWD INTO THE PLAINS LATE TUES. MEANWHILE...UPPER RIDGE WILL AMPLIFY OVER THE ERN CONUS TUES AS STRONG SUBTROPICAL HIGH PRESSURE (+1 STD DEV H5 HEIGHTS) ANCHORS OFF THE SE COAST. AT THE SFC...STRONG HIGH PRESSURE WILL SLOWLY WEAKEN AND DRIFT OFF THE NE COAST TUES-WEDS AS THE COLD FRONT APPROACHES...BUT WILL REMAIN WEDGED INTO THE LOCAL AREA. THE RESULT WILL BE CONTINUED DRY CONDITIONS THRU WED. THE EXCEPTION WILL BE OVER THE FAR SE WED AFTERNOON AS A WEAK COASTAL TROUGH DEVELOPS ALONG THE SE/MID ATLANTIC COAST. WEAK IMPULSES ROUNDING THE UPPER HIGH WILL COMBINE WITH ISENTROPIC LIFT OVER THE COASTAL TROUGH TO PRODUCE AREAS OF LIGHT RAIN. RAIN MAY END UP BEING SOUTH OF THE LOCAL AREA...BUT WILL MAINTAIN A SLIGHT CHANCE FOR NOW. MID-UPPER LEVEL MOISTURE WILL CONTINUE TO RIDE THE SRN STREAM INTO THE OH/TN VALLEYS...ROUNDING THE RIDGE AND PRODUCING PARTLY CLOUDY-MOSTLY CLOUDY SKIES TUES-WEDS OVER THE LOCAL AREA. NE ONSHORE FLOW WILL ALSO RESULT IN CONSIDERABLE LOW LEVEL CLOUDINESS AS WELL. LOW LEVEL RETURN FLOW WILL COMMENCE LATE WEDS AS THE SFC/H85 HIGH MOVES OVER THE WRN ATLANTIC. ANOMALOUS MOISTURE WILL ADVECT INTO THE OH/TN VALLEYS IN ADVANCE OF THE FRONT LATE WEDS. THEREAFTER...MODELS DEVIATE FROM THE PREVIOUS DAYS WITH HANDLING THE TROUGH AS IT MOVES ACROSS THE CNTRL APPALACHIANS. TROUGH WILL EJECT FROM THE MIDWEST INTO THE NE THURS...PUSHING THE BEST DYNAMICS/MOISTURE NORTH OF THE REGION. PRECIP NOW EXPECTED TO DEVELOP OVER THE LOCAL AREA (MAINLY E OF INTERSTATE 95) IN ADVANCE OF THE FRONT THURS AS THE PRECIP ALONG THE FRONT LIKELY DISSIPATES OVER THE MOUNTAINS. DISTURBANCES IN THE SW FLOW AND THETA-E ADVECTION (MODEST LOW LEVEL INSTABILITY) MAKE THIS SCENE RIO SEEM REASONABLE. HAVE OPTED TO TRIM BACK POPS OVER THE PIEDMONT THURS AND RAISE POPS ALONG THE COAST. REGARDLESS...QPF AMOUNTS WILL BE LIGHT WITH AMOUNTS GENERALLY LESS THAN ONE QUARTER OF AN INCH (STILL REMAINING CHANCE POPS). FRONT WILL CROSS THE REGION LATE THURS. WHILE CAA WILL WANE TUES AS HIGH PRESSURE MOVES OFFSHORE...HIGHS WILL AGAIN BE BELOW NORMAL (MID 50S N TO MID 60S S) DUE TO LITTLE CHANCE IN LOW LEVEL THICKNESSES. WARMER WED AND THURS IN ADVANCE OF THE FRONT WITH HIGHS NEURALLY IN THE MID-UPPER 60S. MILD WED NIGHT WITH LOWS ONLY IN THE MID 50S. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... PATTERN SLOWLY CHANGING TO MORE ZONAL FROM THE MORE AMPLIFIED PATTERN WHICH HAS BEEN ACROSS THE CONUS. THIS IS GENERALLY FOLLOWED BY ALL THE MODELS WITH A SLIGHT PREFERENCE TO THE ECMWF. WILL LOOK FOR NOT MUCH CHANCE OF ANY PRECIPITATION DURING THE EXTENDED TIME FRAME. A COLD FRONT WILL BE MOVING OFF THE COAST THURSDAY NIGHT AND THEN HIGH PRESSURE WILL SETTLE OVER THE AREA. WILL HAVE ANOTHER TROF GO BY TO THE NORTH WHICH WILL PUSH A WEAKENING FRONT THROUGH THE AREA ON SUNDAY. THE MAIN IMPACT OF THIS FRONT WILL BE A FEW MORE CLOUDS FRO SATURDAY NIGHT AND SUNDAY. TEMPERATURES WILL GENERALLY BE NEAR TO A LITTLE BELOW NORMAL THROUGH THE PERIOD. WITH SOME CLEAR NIGHTS AND CALM WINDS AS THE HIGH SETTLES ACROSS THE AREA WILL HAVE NIGHTTIME LOWS AGAIN IN THE 30S AT TIMES. && .AVIATION /21Z MONDAY THROUGH SATURDAY/... WHILE VFR CONDITIONS PERSIST ACROSS INLAND AREAS AROUND RIC AND AREA OF MVFR (BKN020-BKN025) HAS PUSHED IN ACROSS SE VA AND NE NC THIS AFTERNOON ON THE STRONG NLY FLOW. AS THE MARINE LAYER MOISTURE REMAINS TRAPPED UNDER A STRONG INVERSION EXPECT THE MVFR CONDITIONS TO PERSIST FROM PHF TO ORF AND ECG INTO THE EVENING AND OVERNIGHT HOURS. SOME BRIEF IFR CONDITIONS MAY BE POSSIBLE JUST PRIOR TO DAYBREAK NEAR THE COAST BUT THESE IFR CONDITIONS WOULD BE LIMITED TO JUST EITHER SIDE OF DAYBREAK. MVFR CONDITIONS WILL SPREAD INLAND LATE TONIGHT INTO EARLY TUE (REACHING RIC BEFORE 12Z TUE) DUE TO LOW LEVEL ONSHORE WINDS. MVFR CONDITIONS WILL ALSO PUSH INTO SBY AND PERSIST TROUGH THE EVENING AND OVERNIGHT HOURS. NEXT CHC FOR MORE WIDESPREAD MVFR CONDS WILL BE THU/THU NGT IN ASSOCIATION WITH NEXT CDFNTL PASSAGE. && .MARINE... WILL CONTINUE THE SMALL CRAFT INTO THE EVENING OVER THE CHESAPEAKE BAY AS THE WINDS CONTINUE TO GUSTS TO 20 KTS. LOOKING AT THE HIGH RES MODELS SUCH AS THE THE HRRR LOCAL WRF AND HIRES ARW ALL SHOWS WINDS DIMINISHING EARLY THIS EVENING. WILL THEREFORE BRING WINDS DOWN ACROSS THE AREA OVERNIGHT. WINDS WILL CONTINUE OUT OF THE NORTHEAST AND WITH LARGE HIGH TO THE NORTH WILL HAVE LONG OCEAN FETCH GENERATING WAVES OF 5 TO 6 FEET ACROSS THE COASTAL WATERS AND THIS WILL BE SLOW TO DIMINISH. PROBABLY SEAS WILL DROP UNDER 5 FEET OVER THE COASTAL WATERS DURING TUESDAY AFTERNOON. BY WEDNESDAY NIGHT AND THURSDAY WINDS WILL SHIFT TO THE SOUTH AND THEN SOUTHWEST AHEAD OF AN APPROACHING COLD FRONT. THE FRONT CROSSES THE WATERS THURSDAY AFTERNOON OR EARLY THURSDAY NIGHT. THE GFS IS A LITTLE QUICKER THEN THE NAM BUT LEANING TOWARD THE SLIGHTLY SLOWER SOLUTION OF THE NAM FOR NOW. SHOULD SEE ANOTHER PERIOD OF SMALL CRAFT WINDS AFTER THE FRONT PASSES THURSDAY NIGHT AND FRIDAY. HIGH PRESSURE THEN BUILDS OVER THE WATER THROUGH THE WEEKEND WITH WINDS BECOMING LIGHTER AND SAS DIMINISHING. && .AKQ WATCHES/WARNINGS/ADVISORIES... MD...NONE. NC...NONE. VA...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL NOON EST TUESDAY FOR ANZ634-650-652- 654. SMALL CRAFT ADVISORY UNTIL 7 PM EST THIS EVENING FOR ANZ630>633. SMALL CRAFT ADVISORY UNTIL 6 PM EST TUESDAY FOR ANZ656-658. && $$ SYNOPSIS...JDM NEAR TERM...SAM SHORT TERM...SAM LONG TERM...JAB AVIATION...ALB/JAO MARINE...JAB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
416 PM EST MON NOV 4 2013 .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 414 PM EST MON NOV 4 2013 WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL TROUGH OVER THE WRN CONUS AND A RIDGE OVER THE EAST RESULTING IN SW FLOW THROUGH THE PLAINS INTO THE NRN GREAT LAKES. A SHORTWAVE TROUGH MOVING THROUGH NRN MN ALONG WITH ISENTROPIC LIFT 295K-300K ISENTROPIC LIFT AHEAD OF A SFC TROUGH IN ERN MN SUPPORTED AN AREA OF RAIN ACROSS NE MN AND WRN LAKE SUPERIOR. FARTHER EAST...AWAY FROM THE STRONGER 700-300 MB QVECTOR CONV...MAINLY JUST SCT LIGHT SHOWERS OR SPRINKLES HAD DEVELOPED OVER WEST UPPER MI. TONIGHT...THE POTENTIAL FOR SOME SCT LIGHT SHOWERS OR SPRINKLES REMAINS ACROSS THE CWA THIS EVENING AS THE AREA OF FAVORABLE ISENTROPIC LIFT ADVANCES THROUGH THE AREA. AS THE NE MN SHRTWV LIFTS TO THE N OF LAKE SUPERIOR...IT WILL PUSH AN ASSOCIATED COLD FRONT THROUGH UPPER MI BRINGING DRIER AIR INTO THE REGION AND ENDING ANY LINGERING LIGHT PCPN. PARTIAL CLEARING IS ALSO EXPECTED...PER UPSTREAM TRENDS OVER MN. THE GUSTY WINDS TO AROUND 30 MPH OVER THE CNTRL AND ERN CWA WILL DIMINISH THIS EVENING AS THE PRES GRADIENT WEAKENS AHEAD OF THE APPROACHING FRONT. TUESDAY...SOME MORNING SUNSHINE WILL GIVE WAY TO INCREASING MID/HIGH CLOUDS BY LATE MORNING AND AFTERNOON AS 300K ISENTROPIC LIFT AGAIN INCREASES AHEAD OF THE STRENGTHENING 700 MB FRONTAL ZONE FROM SW MN IA INTO NRN WI. WITH THE AREA FALLING UNDER THE INFLUENCE OF THE RIGHT ENTRANCE OF THE 250-300 MB JET AND 800-600 FGEN...SOME LIGHT RAIN MAY MOVE INTO THE WEST NEAR THE WI BORDER. HOWEVER...THE BULK OF THE PCPN IS EXPECTED TO HOLD OFF UNTIL AFTER 00Z/WED. WITH THE SUNSHINE AND SW WINDS...TEMPS SHOULD CLIMB ABOVE NORMAL INTO THE MID AND UPPER 40S. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 414 PM EST MON NOV 4 2013 MUCH OF THE LONG TERM FOCUS IS ON THE POTENTIAL FOR MEASURABLE SNOWFALL OVER PORTIONS OF WESTERN UPPER MICHIGAN TUESDAY NIGHT INTO WEDNESDAY MORNING. THE SNOWFALL POTENTIAL WILL BE ASSOCIATED WITH A LOW PRESSURE SYSTEM DEVELOPING ON THE SURFACE TROUGH THAT MOVES ACROSS THE AREA TONIGHT. THE LOW WILL DEVELOP NEAR THE TEXAS PANHANDLE ON TUESDAY AND THEN TRACK NORTHEAST INTO THE GREAT LAKES REGION TUESDAY NIGHT AND WEDNESDAY. PRECIPITATION SHOULD QUICKLY SPREAD NORTH INTO THE CWA ON TUESDAY NIGHT AS THE AREA IS UNDER A COUPLED JET (RIGHT REAR OF JET OVER ONTARIO AND LEFT FRONT OF JET ROUNDING THE UPPER TROUGH AND INTO THE LOWER GREAT LAKES). A LITTLE LOWER IN THE ATMOSPHERE...ISENTROPIC ASCENT AND WARM AIR ADVECTION WILL SPREAD INTO UPPER MICHIGAN WITH THE BEST FORCING ALONG AND TO THE NORTH OF THE INVERTED SURFACE TROUGH STRETCHING NORTHEAST ACROSS NORTHERN LAKE MICHIGAN. MODELS ARE ALL SHOWING A TIGHT THERMAL GRADIENT CUTTING ACROSS THE CENTRAL PART OF UPPER MICHIGAN...LIKELY LEADING TO A SHARP CHANGE OVER FROM RAIN OVER THE EAST AND SNOW OVER THE WEST. TO COMPLICATE THE PRECIPITATION TYPE FORECAST FURTHER...TEMPERATURES IN THE 40S AHEAD OF THIS LOW ON TUESDAY AFTERNOON WILL BE SLOW TO FALL WITH THE INCREASING CLOUD COVER DURING THE AFTERNOON AND EVENING AND LIMITED COLD AIR TO PULL SOUTH AS THE WINDS TURN FROM THE SOUTHWEST TO NORTHEAST ON THE NORTH SIDE OF THE TROUGH. IN ADDITION...THAT LOW LEVEL WARM AIR WILL COMBINE WITH THE WARMER WATER TEMPS OFF LAKE SUPERIOR TO KEEP TEMPERATURES WARMER ALONG THE LAKE SHORE REGIONS. THUS...THINKING THE BEST OPPORTUNITY FOR A CHANGE OVER TO SNOW WILL BE THE HIGHER TERRAIN OF WESTERN UPPER MICHIGAN...FROM BESSEMER TO ROCKLAND AND EAST TO THE HURON MOUNTAINS AND CRYSTAL FALLS. THE KEWEENAW PENINSULA IS COMPLICATED DUE TO ITS PROXIMITY TO LAKE SUPERIOR AND LOOKING AT MODEL SOUNDINGS...THINK THERE WILL BE ENOUGH WARM AIR TO HAVE A MIX OF RAIN/SNOW OVER THE HIGHER TERRAIN LOCATIONS. SINCE THIS IS A SITUATION OF SNOW ALOFT FALLING THROUGH NEAR SURFACE WARM OR ISOTHERMAL LAYER...HAVE FOLLOWED 1000-850MB THICKNESS AND WETBULB0 VALUES TO DELINEATE THE RAIN/SNOW LINE. THAT RAIN/SNOW LINE AWAY FROM THE LAKE SUPERIOR WARMING WILL LIKELY RUN FROM SKANDIA TO IRON MOUNTAIN. AS FOR QPF AMOUNTS...EXPECT 0.40-1.0 INCH OF LIQUID ACROSS THE CWA WITH THE LOWEST AMOUNTS FROM IRONWOOD TO HOUGHTON AND THE GREATEST AMOUNTS SOUTHEAST OF MARQUETTE AND IRON MOUNTAIN. WILL NEED TO KEEP AN EYE ON PORTIONS OF WESTERN UPPER MICHIGAN...AS SOME OF THE MODELS ARE HINTING AT SOME ENHANCED PRECIPITATION WITH A FGEN BAND FROM ROUGHLY WATERSMEET TO BARAGA COUNTY. IN THAT SAME REALM...SOME OF THE HIGHER RESOLUTION RUNS ARE SHIFTING THE QPF A LITTLE FARTHER SOUTHEAST...SO THAT WILL ALSO BE SOMETHING TO WATCH. LOOKING AT SOUNDINGS AND THE EXPECTED FORCING LOCATIONS...EXPECT MUCH OF THE LIFT TO BE JUST BELOW THE DGZ WHICH SHOULD KEEP SNOW RATIOS CLOSER TO 10-1. THUS...WITH THE EXPECTED QPF AMOUNTS OVER THE WESTERN SNOW AREAS WOULD EXPECT SNOWFALL AMOUNTS OF 3 TO 5 INCHES AND THAT SITS RIGHT IN THE ADVISORY CRITERIA. SINCE THERE IS STILL SOME TIME (DUE TO THE MAIN IMPACTS OCCURRING DURING THE WEDNESDAY MORNING COMMUTE)...WILL ISSUE AN SPS FOR PORTIONS OF WESTERN UPPER MICHIGAN HIGHLIGHTING THE POTENTIAL FOR SEVERAL INCHES OF ACCUMULATING SNOWFALL. AS THE LOW TRACKS NORTHEAST ACROSS NORTHERN LAKE MICHIGAN ON WEDNESDAY MORNING AND INTO CANADA DURING THE AFTERNOON...WOULD EXPECT THE PRECIPITATION TO DIMINISH FROM WEST TO EAST THROUGH THE DAY. AS COLDER AIR AND BETTER LOW LEVEL MOISTURE FLOWS SOUTHEAST ACROSS LAKE SUPERIOR ON WEDNESDAY NIGHT...EXPECT THERE TO BE SOME LAKE EFFECT SNOW SHOWERS IN THE NORTHWEST WIND BELTS. 850MB TEMPS ARE IN THE -7 TO -9C RANGE DEPENDING ON MODEL...SO DELTA-T VALUES ARE IN THE MID-UPPER TEENS. INVERSION HEIGHTS LOOK TO PEAK IN THE 7-8KFT RANGE...SO SHOULD SEE AT LEAST SOME STRONGER SNOW SHOWERS. AT THIS POINT...ONLY HAVE A DUSTING OF SNOW IN THE FORECASTS FOR THE SNOW BELTS. DRIER AIR WILL BEGIN WORKING OVER LAKE SUPERIOR FROM THE WEST ON THURSDAY AND THURSDAY NIGHT AS A HIGH PRESSURE RIDGE FROM A HIGH EXITING THE CENTRAL PLAINS MOVES OVER THE AREA. THEREFORE...SHOWED DIMINISHING POPS THROUGH THAT PERIOD...WITH THEM LINGERING LONGEST IN THE WEST-NORTHWEST FAVORED LOCATION OVER THE EAST. THIS HIGH PRESSURE RIDGE SHOULD BRING DRY WEATHER TO THE AREA FOR MUCH OF FRIDAY. THE NEXT UPPER DISTURBANCE AND LOW PRESSURE SYSTEM WILL MOVE EAST OUT OF THE NORTHERN PLAINS ON FRIDAY AND THROUGH THE UPPER GREAT LAKES FRIDAY NIGHT AND SATURDAY. MODELS IN DECENT AGREEMENT ON THE TRACK OF THE LOW AND THE QPF ON THE NORTH SIDE OF THE LOW THAT WILL BE MOVING THROUGH UPPER MICHIGAN. BASED OFF SNOW ALOFT FALLING THROUGH A WARM LAYER NEAR THE SURFACE...LEANED ON 1000-850MB THICKNESS VALUES FOR P-TYPE WHICH INDICATES A RAIN/SNOW MIXTURE. A LOT OF VARIABILITY ON THE BACK SIDE OF THE LOW WITH HOW COLD THE AIR WILL BE WITH THE NORTHWEST WINDS ON SATURDAY NIGHT INTO SUNDAY MORNING. THIS COULD PRODUCE SOME LIGHT LAKE EFFECT PRECIPITATION...BUT CONFIDENCE IS TOO LOW TO GO WITH MORE THAN LOW CHANCE POPS. HIGH PRESSURE THEN LOOKS TO MOVE INTO THE UPPER GREAT LAKES FOR SUNDAY AFTERNOON INTO SUNDAY NIGHT AND LEAD TO DRY CONDITIONS. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 341 PM EST MON NOV 4 2013 LOW LEVEL MOISTURE MOVING INTO THE AREA WITH STRONG SRLY FLOW AHEAD OF A TROUGH INTO MN HAS SUPPORTED MVFR CIGS AT CMX/SAW. HOWEVER...DOWNSLOPE FLOW AT IWD HAS KEPT CIGS IN THE VFR RANGE. LIGHT RAIN INTO THE AREA THIS AFTERNOON INTO THE EVENING IS EXPECTED TO REMAIN LIGHT ENOUGH SO THAT VSBY WILL NOT BE AFFECTED. GUSTY SOUTH WINDS WILL CONTINUE INTO THIS EVENING...ESPECIALLY AT SAW WITH GUSTS REACHING 30 KNOTS. VEERING WINDS TO WSW BRINGING DRIER AIR INTO THE UPPER MI WILL HELP PUSH THE LOWER CLOUDS TO THE EAST WITH VFR CONDITIONS RETURNING OVERNIGHT. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 414 PM EST MON NOV 4 2013 AS LOW PRES MOVES FROM LAKE WINNIPEG TO HUDSON BAY ON TONIGHT...IT WILL DRAG A TROUGH ACROSS CNTRL/ERN LAKE SUPERIOR AND BRING AN END TO THE GALES BY LATE THIS EVENING. WINDS WILL STILL BE GUSTY OUT OF THE SOUTHWEST ON TUESDAY MORNING (TO 30KTS)...BUT THEN WILL QUICKLY DIMINISH TUESDAY EVENING AS A LOW TAKES SHAPE OVER THE CENTRAL PLAINS. THIS LOW WILL TRACK NORTHEAST THROUGH NORTHERN LAKE MICHIGAN ON WEDNESDAY AFTERNOON AND EVENING...BUT AT THIS POINT WINDS ON THE BACK SIDE OF THE LOW ARE EXPECTED TO STAY BELOW 30KTS. A HIGH PRESSURE RIDGE WILL SLIDE INTO THE AREA ON THURSDAY AFTERNOON AND REMAIN THROUGH FRIDAY...KEEPING WINDS BELOW 25KTS. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... GALE WARNING UNTIL MIDNIGHT EST TONIGHT FOR LSZ266-267. GALE WARNING UNTIL 7 PM EST THIS EVENING FOR LSZ244-245-249>251- 264-265. LAKE MICHIGAN... GALE WARNING UNTIL 10 PM EST THIS EVENING FOR LMZ221-248-250. && $$ SHORT TERM...JLB LONG TERM...SRF MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
341 PM EST MON NOV 4 2013 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 458 AM EST MON NOV 4 2013 WATER VAPOR LOOP AND RAP ANALYSIS SHOWS A SERIES OF SHORTWAVES UPSTREAM...ONE OVER SOUTHERN SASKATCHEWAN...A SECOND OVER THE CENTRAL PLAINS...A THIRD OVER THE COLORADO ROCKIES...A FOURTH DIGGING INTO THE CA COASTLINE AND A FIFTH DIVING THROUGH THE PAC NW. THE INITIAL SHORTWAVE OVER THE CENTRAL PLAINS AND ASSOC STRONG WAA/ISENTROPIC LIFT AHEAD OF THIS FEATURE IS PRODUCING RADAR RETURNS FROM ERN IA NORTH INTO WRN LAKE SUPERIOR/WRN UPPER MI. MUCH OF THE RADAR REFLECTIVITY HOWEVER IS RESULTING IN LITTLE IF ANY PCPN AT SFC THUS FAR AS NOTED ON OBS UPSTREAM. THE SHORTWAVES OVER SCNTRL CANADA AND THE ROCKIES WILL HELP PROPEL A COLD FRONT THROUGH THE FCST AREA TONIGHT AS THEY LIFT NE TOWARD HUDSON BAY. THE WRN CONUS SHORTWAVES WILL EVENTUALLY CONGEAL AND PUSH A PROGRESSIVE POSITIVE TILT TROF AND ASSOC SFC LOW THROUGH THE GREAT LAKES BY MIDWEEK. TODAY...CONTINUED ISENTROPIC ASCENT AND COLUMN MOISTENING THROUGH THE MORNING HRS WILL EVENTUALLY ALLOW PCPN TO BE REALIZED AT THE SFC. THE BEST FORCING WILL BE ALONG A CORRIDOR AHEAD OF AN APPROACHING COLD FRONT WHICH WILL REACH INTO THE WRN THIRD OF UPPER MI. WILL MAINTAIN HIGH CHC TO LIKELY POPS FOR SHRA OVER THESE COUNTIES AND THEN TAPER POPS BACK TO LOW CHC OVER CENTRAL COUNTIES TO SLIGHT CHC OVER FAR EAST FARTHEST AWAY FROM BEST FORCING. TIGHTENING SRLY GRADIENT AHEAD OF THE APPROACHING FRONTAL SYSTEM WILL ALLOW WINDS TO GUST NEAR 40 MPH AT TIMES OVER THE ERN HALF OF THE FCST AREA THIS AFTERNOON. EXPECT TEMPS TO REACH INTO THE UPPER 40S TO AROUND 50F UNDER MOSTLY CLOUDY SKIES. TONIGHT...AS THE WELL-DEFINED SHORTWAVE NOW OVER THE CENTRAL PLAINS LIFTS THROUGH THE NRN PLAINS THIS AFTERNOON AND THEN NORTH OF LAKE SUPERIOR TONIGHT...IT WILL PROPEL THE ASSOCIATED COLD FRONT OVER THE NRN PLAINS INTO THE WEST HALF OF UPPER MI THIS EVENING AND THEN THROUGH THE REST OF UPPER MI LATE TONIGHT. WITH THIS SHORTWAVE LIFTING WELL N OF THE AREA AND WITH THE NEXT SHORTWAVE STILL OVER THE ROCKIES IN THE BASE OF THE WRN CONUS TROF...EXPECT A DRYING TREND ALONG THE FRONTAL BOUNDARY LATE TONIGHT INTO TUE AS FORCING ALONG BOUNDARY FALLS APART. WILL CONTINUE TO TREND POPS DOWN TO SCHC WITH TIME ALONG FRONT TONIGHT AND EXPECT DRY CONDITIONS FOR THE CWA BY 06Z OR SHORTLY THEREAFTER. MIN TEMPS TONIGHT WILL BE COOLEST OVER THE WRN INTERIOR (UPPER 20S TO AROUND 30F) WHERE LONGEST PD OF CLEARING IS EXPECTED BEHIND THE FRONT. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 530 AM EST MON NOV 4 2013 WILL START OFF TUESDAY MORNING UNDER QUICK SW FLOW ALOFT...WITH A RIDGE STUCK ACROSS THE FAR SE STATES AND THE MAIN 500MB LOW ACROSS MANITOBA AND FAR N ONTARIO...WITH A SIGNIFICANT TROUGH EXTENDING FROM S CENTRAL CANADA THROUGH MT AND AZ TO MEXICO. THE NEARLY STACKED 500MB TO SFC LOW OVER N ONTARIO AT 12Z TUESDAY WILL HAVE A COLD FRONT PUSHED ACROSS E UPPER MI...TETHERED TO THE NEXT SFC LOW SET UP ALONG THE CO/NM BORDER. EXPECT DRY WX INITIALLY...THANKS TO MUCH OF THE ENERGY STUCK TO OUR N...CLOSER TO THE LARGE WRAPPED UP LOW. THIS DRY WEATHER WILL BE SHORT LIVED AS THE SW LOW GETS PUSHED ALONG BY THE PROGRESSIVE POSITIVELY TILTED TROUGH. AS THE 500MB TROUGH PUSHES ACROSS THE CENTRAL PLAINS STATES THE SFC LOW WILL BE KICKED NNE ALONG THE LINGERING WEAK FRONTAL BOUNDARY. THE LOW SHOULD PUSH UP TO S WI BY 12Z WEDNESDAY...ALLOWING A SWATH OF OF MOISTURE TO QUICKLY SLIDE N ACROSS IL AND ON 40-50KT SW 850MB WINDS. COMPARING THE 04/00Z MODELS...THE CANADIAN STILL LOOKS TO BE ON THE SLOWER SIDE WITH THE TRACK OF THE SFC LOW OVER LAKE MI AND LAKE HURON WEDNESDAY AFTERNOON/EVENING. WILL CONTINUE TO MENTION THE POTENTIAL FOR 3 OR MORE INCHES OF SNOW IN THE HWO FOR TUESDAY NIGHT THROUGH WEDNESDAY. WITH TOO MANY UNKNOWNS...WILL KEEP FROM GETTING TOO SPECIFIC AT THIS TIME. WHILE BUFKIT IS SHOWING THE POTENTIAL FOR 4-6IN OF SNOW FROM 00-15Z WEDNESDAY OFF THE NAM AT IWD...THE GFS IS CLOSER TO 1-2IN OF NEW SNOW. WENT WITH A MORE BROAD 1-4IN WITH THE HIGHEST AMOUNTS OVER THE HIGHER TERRAIN OF GOGEBIC AND ONTONAGON COUNTIES. THE DGZ IS WAY UP BETWEEN 500 AND 600MB...WITH SNOW RATIOS MAXING OUT NEAR 10:1. WHILE SNOW WILL BE THE PREDOMINANT WX TYPE OVER THE W THIRD OF UPPER MI...WARMER AIR WILL BE TRAPPED EAST UNTIL THE LOW EXITS WEDNESDAY EVENING. EITHER WAY TUESDAY NIGHT THROUGH WEDNESDAY EVENING LOOK WET...WITH A CWA AVERAGE INCH OF WATER. THIS IS EVEN A BIT LOWER THAN OUR PREVIOUS ESTIMATE FROM YESTERDAY AFTERNOON...AS THE FOCUS SHIFTS A BIT CLOSER TO LAKE MI. THE MAIN SHORTWAVE OVER THE W THIRD AT 00Z THURSDAY WILL EXIT E OVERNIGHT...WITH MUCH COOLER AIR /850MB TEMPS NEARING -9C/ SLIDING OVER THE W. ALL SNOW LOOKS REASONABLE FOR OUR LAND AREAS AFTER 06Z THURSDAY. HOWEVER WITH SFC TEMPS STILL IN THE MID 30S...EXPECT LIMITED ACCUMULATIONS IF ANY E. IT CONTINUES TO BE DIFFICULT TO TIME THE END OF THE LAKE EFFECT/LAKE ENHANCED SNOW SHOWERS BEHIND THE EXITING SFC LOW WEDNESDAY NIGHT AND THURSDAY...AS A STRONG RIDGE OF HIGH PRESSURE QUICKLY BUILDS ACROSS UPPER MI TURING WINDS TO A MORE W DIRECTION. WILL NOT GET TOO SPECIFIC WITH POPS/WX/WINDS FOR WEDNESDAY AFTERNOON ON...AS THERE ARE SEVERAL DISCREPANCIES THAT COULD HAVE SIGNIFICANT IMPACT ON ANY SNOW ACCUMULATIONS. DRY WX SHOULD AGAIN BE THE RULE FOR MOST THURSDAY AFTERNOON THROUGH FRIDAY...EVEN THROUGH NW FLOW ALOFT WILL PUSH A SERIES OF SHORTWAVES THROUGH THE REGION INITIALLY THURSDAY NIGHT. INCREASED CLOUD COVER WILL BE THE MAIN RESULT...AS HIGH PRESSURE BUILDS IN AT THE SFC AND ALOFT. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 341 PM EST MON NOV 4 2013 LOW LEVEL MOISTURE MOVING INTO THE AREA WITH STRONG SRLY FLOW AHEAD OF A TROUGH INTO MN HAS SUPPORTED MVFR CIGS AT CMX/SAW. HOWEVER...DOWNSLOPE FLOW AT IWD HAS KEPT CIGS IN THE VFR RANGE. LIGHT RAIN INTO THE AREA THIS AFTERNOON INTO THE EVENING IS EXPECTED TO REMAIN LIGHT ENOUGH SO THAT VSBY WILL NOT BE AFFECTED. GUSTY SOUTH WINDS WILL CONTINUE INTO THIS EVENING...ESPECIALLY AT SAW WITH GUSTS REACHING 30 KNOTS. VEERING WINDS TO WSW BRINGING DRIER AIR INTO THE UPPER MI WILL HELP PUSH THE LOWER CLOUDS TO THE EAST WITH VFR CONDITIONS RETURNING OVERNIGHT. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 458 AM EST MON NOV 4 2013 A TIGHTENING PRESSURE GRADIENT BETWEEN A HIGH MOVING EAST THROUGH QUEBEC AND A LOW SLIDING EAST THROUGH SOUTHERN SASKATCHEWAN HAS LED TO INCREASING SOUTHERLY FLOW ACROSS LAKE SUPERIOR TODAY. SOUTHERLY GALES TO 35-40KTS ARE EXPECTED OVER THE EASTERN HALF OF THE LAKE WHERE GALE WARNING ARE POSTED. AS THE LOW MOVES FROM LAKE WINNIPEG TO HUDSON BAY ON TONIGHT...IT WILL DRAG A TROUGH ACROSS LAKE SUPERIOR AND BRING AN END TO THE GALES DURING THE OVERNIGHT HOURS. WINDS WILL STILL BE GUSTY OUT OF THE SOUTHWEST ON TUESDAY MORNING (TO 30KTS)...BUT THEN WILL QUICKLY DIMINISH TUESDAY EVENING AS A LOW TAKES SHAPE OVER THE CENTRAL PLAINS. THIS LOW WILL TRACK NORTHEAST THROUGH NORTHERN LAKE MICHIGAN ON WEDNESDAY AFTERNOON AND EVENING...BUT AT THIS POINT WINDS ON THE BACK SIDE OF THE LOW ARE EXPECTED TO STAY BELOW 30KTS. A HIGH PRESSURE RIDGE WILL SLIDE INTO THE AREA ON THURSDAY AFTERNOON AND REMAIN THROUGH FRIDAY...KEEPING WINDS BELOW 25KTS. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... GALE WARNING UNTIL MIDNIGHT EST TONIGHT FOR LSZ266-267. GALE WARNING UNTIL 7 PM EST THIS EVENING FOR LSZ244-245-249>251- 264-265. LAKE MICHIGAN... GALE WARNING UNTIL 10 PM EST THIS EVENING FOR LMZ221-248-250. && $$ SHORT TERM...VOSS LONG TERM...KF AVIATION...JLB MARINE...VOSS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
737 AM EST MON NOV 4 2013 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 458 AM EST MON NOV 4 2013 WATER VAPOR LOOP AND RAP ANALYSIS SHOWS A SERIES OF SHORTWAVES UPSTREAM...ONE OVER SOUTHERN SASKATCHEWAN...A SECOND OVER THE CENTRAL PLAINS...A THIRD OVER THE COLORADO ROCKIES...A FOURTH DIGGING INTO THE CA COASTLINE AND A FIFTH DIVING THROUGH THE PAC NW. THE INITIAL SHORTWAVE OVER THE CENTRAL PLAINS AND ASSOC STRONG WAA/ISENTROPIC LIFT AHEAD OF THIS FEATURE IS PRODUCING RADAR RETURNS FROM ERN IA NORTH INTO WRN LAKE SUPERIOR/WRN UPPER MI. MUCH OF THE RADAR REFLECTIVITY HOWEVER IS RESULTING IN LITTLE IF ANY PCPN AT SFC THUS FAR AS NOTED ON OBS UPSTREAM. THE SHORTWAVES OVER SCNTRL CANADA AND THE ROCKIES WILL HELP PROPEL A COLD FRONT THROUGH THE FCST AREA TONIGHT AS THEY LIFT NE TOWARD HUDSON BAY. THE WRN CONUS SHORTWAVES WILL EVENTUALLY CONGEAL AND PUSH A PROGRESSIVE POSITIVE TILT TROF AND ASSOC SFC LOW THROUGH THE GREAT LAKES BY MIDWEEK. TODAY...CONTINUED ISENTROPIC ASCENT AND COLUMN MOISTENING THROUGH THE MORNING HRS WILL EVENTUALLY ALLOW PCPN TO BE REALIZED AT THE SFC. THE BEST FORCING WILL BE ALONG A CORRIDOR AHEAD OF AN APPROACHING COLD FRONT WHICH WILL REACH INTO THE WRN THIRD OF UPPER MI. WILL MAINTAIN HIGH CHC TO LIKELY POPS FOR SHRA OVER THESE COUNTIES AND THEN TAPER POPS BACK TO LOW CHC OVER CENTRAL COUNTIES TO SLIGHT CHC OVER FAR EAST FARTHEST AWAY FROM BEST FORCING. TIGHTENING SRLY GRADIENT AHEAD OF THE APPROACHING FRONTAL SYSTEM WILL ALLOW WINDS TO GUST NEAR 40 MPH AT TIMES OVER THE ERN HALF OF THE FCST AREA THIS AFTERNOON. EXPECT TEMPS TO REACH INTO THE UPPER 40S TO AROUND 50F UNDER MOSTLY CLOUDY SKIES. TONIGHT...AS THE WELL-DEFINED SHORTWAVE NOW OVER THE CENTRAL PLAINS LIFTS THROUGH THE NRN PLAINS THIS AFTERNOON AND THEN NORTH OF LAKE SUPERIOR TONIGHT...IT WILL PROPEL THE ASSOCIATED COLD FRONT OVER THE NRN PLAINS INTO THE WEST HALF OF UPPER MI THIS EVENING AND THEN THROUGH THE REST OF UPPER MI LATE TONIGHT. WITH THIS SHORTWAVE LIFTING WELL N OF THE AREA AND WITH THE NEXT SHORTWAVE STILL OVER THE ROCKIES IN THE BASE OF THE WRN CONUS TROF...EXPECT A DRYING TREND ALONG THE FRONTAL BOUNDARY LATE TONIGHT INTO TUE AS FORCING ALONG BOUNDARY FALLS APART. WILL CONTINUE TO TREND POPS DOWN TO SCHC WITH TIME ALONG FRONT TONIGHT AND EXPECT DRY CONDITIONS FOR THE CWA BY 06Z OR SHORTLY THEREAFTER. MIN TEMPS TONIGHT WILL BE COOLEST OVER THE WRN INTERIOR (UPPER 20S TO AROUND 30F) WHERE LONGEST PD OF CLEARING IS EXPECTED BEHIND THE FRONT. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 530 AM EST MON NOV 4 2013 WILL START OFF TUESDAY MORNING UNDER QUICK SW FLOW ALOFT...WITH A RIDGE STUCK ACROSS THE FAR SE STATES AND THE MAIN 500MB LOW ACROSS MANITOBA AND FAR N ONTARIO...WITH A SIGNIFICANT TROUGH EXTENDING FROM S CENTRAL CANADA THROUGH MT AND AZ TO MEXICO. THE NEARLY STACKED 500MB TO SFC LOW OVER N ONTARIO AT 12Z TUESDAY WILL HAVE A COLD FRONT PUSHED ACROSS E UPPER MI...TETHERED TO THE NEXT SFC LOW SET UP ALONG THE CO/NM BORDER. EXPECT DRY WX INITIALLY...THANKS TO MUCH OF THE ENERGY STUCK TO OUR N...CLOSER TO THE LARGE WRAPPED UP LOW. THIS DRY WEATHER WILL BE SHORT LIVED AS THE SW LOW GETS PUSHED ALONG BY THE PROGRESSIVE POSITIVELY TILTED TROUGH. AS THE 500MB TROUGH PUSHES ACROSS THE CENTRAL PLAINS STATES THE SFC LOW WILL BE KICKED NNE ALONG THE LINGERING WEAK FRONTAL BOUNDARY. THE LOW SHOULD PUSH UP TO S WI BY 12Z WEDNESDAY...ALLOWING A SWATH OF OF MOISTURE TO QUICKLY SLIDE N ACROSS IL AND ON 40-50KT SW 850MB WINDS. COMPARING THE 04/00Z MODELS...THE CANADIAN STILL LOOKS TO BE ON THE SLOWER SIDE WITH THE TRACK OF THE SFC LOW OVER LAKE MI AND LAKE HURON WEDNESDAY AFTERNOON/EVENING. WILL CONTINUE TO MENTION THE POTENTIAL FOR 3 OR MORE INCHES OF SNOW IN THE HWO FOR TUESDAY NIGHT THROUGH WEDNESDAY. WITH TOO MANY UNKNOWNS...WILL KEEP FROM GETTING TOO SPECIFIC AT THIS TIME. WHILE BUFKIT IS SHOWING THE POTENTIAL FOR 4-6IN OF SNOW FROM 00-15Z WEDNESDAY OFF THE NAM AT IWD...THE GFS IS CLOSER TO 1-2IN OF NEW SNOW. WENT WITH A MORE BROAD 1-4IN WITH THE HIGHEST AMOUNTS OVER THE HIGHER TERRAIN OF GOGEBIC AND ONTONAGON COUNTIES. THE DGZ IS WAY UP BETWEEN 500 AND 600MB...WITH SNOW RATIOS MAXING OUT NEAR 10:1. WHILE SNOW WILL BE THE PREDOMINANT WX TYPE OVER THE W THIRD OF UPPER MI...WARMER AIR WILL BE TRAPPED EAST UNTIL THE LOW EXITS WEDNESDAY EVENING. EITHER WAY TUESDAY NIGHT THROUGH WEDNESDAY EVENING LOOK WET...WITH A CWA AVERAGE INCH OF WATER. THIS IS EVEN A BIT LOWER THAN OUR PREVIOUS ESTIMATE FROM YESTERDAY AFTERNOON...AS THE FOCUS SHIFTS A BIT CLOSER TO LAKE MI. THE MAIN SHORTWAVE OVER THE W THIRD AT 00Z THURSDAY WILL EXIT E OVERNIGHT...WITH MUCH COOLER AIR /850MB TEMPS NEARING -9C/ SLIDING OVER THE W. ALL SNOW LOOKS REASONABLE FOR OUR LAND AREAS AFTER 06Z THURSDAY. HOWEVER WITH SFC TEMPS STILL IN THE MID 30S...EXPECT LIMITED ACCUMULATIONS IF ANY E. IT CONTINUES TO BE DIFFICULT TO TIME THE END OF THE LAKE EFFECT/LAKE ENHANCED SNOW SHOWERS BEHIND THE EXITING SFC LOW WEDNESDAY NIGHT AND THURSDAY...AS A STRONG RIDGE OF HIGH PRESSURE QUICKLY BUILDS ACROSS UPPER MI TURING WINDS TO A MORE W DIRECTION. WILL NOT GET TOO SPECIFIC WITH POPS/WX/WINDS FOR WEDNESDAY AFTERNOON ON...AS THERE ARE SEVERAL DISCREPANCIES THAT COULD HAVE SIGNIFICANT IMPACT ON ANY SNOW ACCUMULATIONS. DRY WX SHOULD AGAIN BE THE RULE FOR MOST THURSDAY AFTERNOON THROUGH FRIDAY...EVEN THROUGH NW FLOW ALOFT WILL PUSH A SERIES OF SHORTWAVES THROUGH THE REGION INITIALLY THURSDAY NIGHT. INCREASED CLOUD COVER WILL BE THE MAIN RESULT...AS HIGH PRESSURE BUILDS IN AT THE SFC AND ALOFT. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING) ISSUED AT 658 AM EST MON NOV 4 2013 MOIST UPSLOPE SSE FLOW WILL RESULT IN MVFR CIGS AT BOTH KSAW AND KCMX INTO THIS EVENING. CONDITIONS AT KIWD WILL LOWER TO MVFR BY LATE MORNING AS -SHRA MOVE IN FM THE SW. SHRA WILL SPREAD FM THE WRN TAF SITES EARLY THIS AFTERNOON INTO KSAW TOWARD EVENING. AS WINDS SHIFT TO THE WSW BEHIND FRONTAL PASSAGE LATER THIS EVENING...EXPECT CONDITIONS TO IMPROVE TO VFR AT ALL TAF SITES. SOUTHERLY WINDS WILL GUST BETWEEN 25 AND 30 KNOTS TODAY INTO EARLY THIS EVNING AS A TIGHT PRES GRADIENT DEVELOPS AHEAD OF THE APPROACHING COLD FRONT. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 458 AM EST MON NOV 4 2013 A TIGHTENING PRESSURE GRADIENT BETWEEN A HIGH MOVING EAST THROUGH QUEBEC AND A LOW SLIDING EAST THROUGH SOUTHERN SASKATCHEWAN HAS LED TO INCREASING SOUTHERLY FLOW ACROSS LAKE SUPERIOR TODAY. SOUTHERLY GALES TO 35-40KTS ARE EXPECTED OVER THE EASTERN HALF OF THE LAKE WHERE GALE WARNING ARE POSTED. AS THE LOW MOVES FROM LAKE WINNIPEG TO HUDSON BAY ON TONIGHT...IT WILL DRAG A TROUGH ACROSS LAKE SUPERIOR AND BRING AN END TO THE GALES DURING THE OVERNIGHT HOURS. WINDS WILL STILL BE GUSTY OUT OF THE SOUTHWEST ON TUESDAY MORNING (TO 30KTS)...BUT THEN WILL QUICKLY DIMINISH TUESDAY EVENING AS A LOW TAKES SHAPE OVER THE CENTRAL PLAINS. THIS LOW WILL TRACK NORTHEAST THROUGH NORTHERN LAKE MICHIGAN ON WEDNESDAY AFTERNOON AND EVENING...BUT AT THIS POINT WINDS ON THE BACK SIDE OF THE LOW ARE EXPECTED TO STAY BELOW 30KTS. A HIGH PRESSURE RIDGE WILL SLIDE INTO THE AREA ON THURSDAY AFTERNOON AND REMAIN THROUGH FRIDAY...KEEPING WINDS BELOW 25KTS. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... GALE WARNING UNTIL MIDNIGHT EST TONIGHT FOR LSZ266-267. GALE WARNING UNTIL 7 PM EST THIS EVENING FOR LSZ244-245-264-265. GALE WARNING FROM 10 AM THIS MORNING TO 7 PM EST THIS EVENING FOR LSZ249>251. LAKE MICHIGAN... GALE WARNING UNTIL 10 PM EST THIS EVENING FOR LMZ221-248-250. && $$ SHORT TERM...VOSS LONG TERM...KF AVIATION...VOSS MARINE...VOSS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
531 AM EST MON NOV 4 2013 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 458 AM EST MON NOV 4 2013 WATER VAPOR LOOP AND RAP ANALYSIS SHOWS A SERIES OF SHORTWAVES UPSTREAM...ONE OVER SOUTHERN SASKATCHEWAN...A SECOND OVER THE CENTRAL PLAINS...A THIRD OVER THE COLORADO ROCKIES...A FOURTH DIGGING INTO THE CA COASTLINE AND A FIFTH DIVING THROUGH THE PAC NW. THE INITIAL SHORTWAVE OVER THE CENTRAL PLAINS AND ASSOC STRONG WAA/ISENTROPIC LIFT AHEAD OF THIS FEATURE IS PRODUCING RADAR RETURNS FROM ERN IA NORTH INTO WRN LAKE SUPERIOR/WRN UPPER MI. MUCH OF THE RADAR REFLECTIVITY HOWEVER IS RESULTING IN LITTLE IF ANY PCPN AT SFC THUS FAR AS NOTED ON OBS UPSTREAM. THE SHORTWAVES OVER SCNTRL CANADA AND THE ROCKIES WILL HELP PROPEL A COLD FRONT THROUGH THE FCST AREA TONIGHT AS THEY LIFT NE TOWARD HUDSON BAY. THE WRN CONUS SHORTWAVES WILL EVENTUALLY CONGEAL AND PUSH A PROGRESSIVE POSITIVE TILT TROF AND ASSOC SFC LOW THROUGH THE GREAT LAKES BY MIDWEEK. TODAY...CONTINUED ISENTROPIC ASCENT AND COLUMN MOISTENING THROUGH THE MORNING HRS WILL EVENTUALLY ALLOW PCPN TO BE REALIZED AT THE SFC. THE BEST FORCING WILL BE ALONG A CORRIDOR AHEAD OF AN APPROACHING COLD FRONT WHICH WILL REACH INTO THE WRN THIRD OF UPPER MI. WILL MAINTAIN HIGH CHC TO LIKELY POPS FOR SHRA OVER THESE COUNTIES AND THEN TAPER POPS BACK TO LOW CHC OVER CENTRAL COUNTIES TO SLIGHT CHC OVER FAR EAST FARTHEST AWAY FROM BEST FORCING. TIGHTENING SRLY GRADIENT AHEAD OF THE APPROACHING FRONTAL SYSTEM WILL ALLOW WINDS TO GUST NEAR 40 MPH AT TIMES OVER THE ERN HALF OF THE FCST AREA THIS AFTERNOON. EXPECT TEMPS TO REACH INTO THE UPPER 40S TO AROUND 50F UNDER MOSTLY CLOUDY SKIES. TONIGHT...AS THE WELL-DEFINED SHORTWAVE NOW OVER THE CENTRAL PLAINS LIFTS THROUGH THE NRN PLAINS THIS AFTERNOON AND THEN NORTH OF LAKE SUPERIOR TONIGHT...IT WILL PROPEL THE ASSOCIATED COLD FRONT OVER THE NRN PLAINS INTO THE WEST HALF OF UPPER MI THIS EVENING AND THEN THROUGH THE REST OF UPPER MI LATE TONIGHT. WITH THIS SHORTWAVE LIFTING WELL N OF THE AREA AND WITH THE NEXT SHORTWAVE STILL OVER THE ROCKIES IN THE BASE OF THE WRN CONUS TROF...EXPECT A DRYING TREND ALONG THE FRONTAL BOUNDARY LATE TONIGHT INTO TUE AS FORCING ALONG BOUNDARY FALLS APART. WILL CONTINUE TO TREND POPS DOWN TO SCHC WITH TIME ALONG FRONT TONIGHT AND EXPECT DRY CONDITIONS FOR THE CWA BY 06Z OR SHORTLY THEREAFTER. MIN TEMPS TONIGHT WILL BE COOLEST OVER THE WRN INTERIOR (UPPER 20S TO AROUND 30F) WHERE LONGEST PD OF CLEARING IS EXPECTED BEHIND THE FRONT. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 530 AM EST MON NOV 4 2013 WILL START OFF TUESDAY MORNING UNDER QUICK SW FLOW ALOFT...WITH A RIDGE STUCK ACROSS THE FAR SE STATES AND THE MAIN 500MB LOW ACROSS MANITOBA AND FAR N ONTARIO...WITH A SIGNIFICANT TROUGH EXTENDING FROM S CENTRAL CANADA THROUGH MT AND AZ TO MEXICO. THE NEARLY STACKED 500MB TO SFC LOW OVER N ONTARIO AT 12Z TUESDAY WILL HAVE A COLD FRONT PUSHED ACROSS E UPPER MI...TETHERED TO THE NEXT SFC LOW SET UP ALONG THE CO/NM BORDER. EXPECT DRY WX INITIALLY...THANKS TO MUCH OF THE ENERGY STUCK TO OUR N...CLOSER TO THE LARGE WRAPPED UP LOW. THIS DRY WEATHER WILL BE SHORT LIVED AS THE SW LOW GETS PUSHED ALONG BY THE PROGRESSIVE POSITIVELY TILTED TROUGH. AS THE 500MB TROUGH PUSHES ACROSS THE CENTRAL PLAINS STATES THE SFC LOW WILL BE KICKED NNE ALONG THE LINGERING WEAK FRONTAL BOUNDARY. THE LOW SHOULD PUSH UP TO S WI BY 12Z WEDNESDAY...ALLOWING A SWATH OF OF MOISTURE TO QUICKLY SLIDE N ACROSS IL AND ON 40-50KT SW 850MB WINDS. COMPARING THE 04/00Z MODELS...THE CANADIAN STILL LOOKS TO BE ON THE SLOWER SIDE WITH THE TRACK OF THE SFC LOW OVER LAKE MI AND LAKE HURON WEDNESDAY AFTERNOON/EVENING. WILL CONTINUE TO MENTION THE POTENTIAL FOR 3 OR MORE INCHES OF SNOW IN THE HWO FOR TUESDAY NIGHT THROUGH WEDNESDAY. WITH TOO MANY UNKNOWNS...WILL KEEP FROM GETTING TOO SPECIFIC AT THIS TIME. WHILE BUFKIT IS SHOWING THE POTENTIAL FOR 4-6IN OF SNOW FROM 00-15Z WEDNESDAY OFF THE NAM AT IWD...THE GFS IS CLOSER TO 1-2IN OF NEW SNOW. WENT WITH A MORE BROAD 1-4IN WITH THE HIGHEST AMOUNTS OVER THE HIGHER TERRAIN OF GOGEBIC AND ONTONAGON COUNTIES. THE DGZ IS WAY UP BETWEEN 500 AND 600MB...WITH SNOW RATIOS MAXING OUT NEAR 10:1. WHILE SNOW WILL BE THE PREDOMINANT WX TYPE OVER THE W THIRD OF UPPER MI...WARMER AIR WILL BE TRAPPED EAST UNTIL THE LOW EXITS WEDNESDAY EVENING. EITHER WAY TUESDAY NIGHT THROUGH WEDNESDAY EVENING LOOK WET...WITH A CWA AVERAGE INCH OF WATER. THIS IS EVEN A BIT LOWER THAN OUR PREVIOUS ESTIMATE FROM YESTERDAY AFTERNOON...AS THE FOCUS SHIFTS A BIT CLOSER TO LAKE MI. THE MAIN SHORTWAVE OVER THE W THIRD AT 00Z THURSDAY WILL EXIT E OVERNIGHT...WITH MUCH COOLER AIR /850MB TEMPS NEARING -9C/ SLIDING OVER THE W. ALL SNOW LOOKS REASONABLE FOR OUR LAND AREAS AFTER 06Z THURSDAY. HOWEVER WITH SFC TEMPS STILL IN THE MID 30S...EXPECT LIMITED ACCUMULATIONS IF ANY E. IT CONTINUES TO BE DIFFICULT TO TIME THE END OF THE LAKE EFFECT/LAKE ENHANCED SNOW SHOWERS BEHIND THE EXITING SFC LOW WEDNESDAY NIGHT AND THURSDAY...AS A STRONG RIDGE OF HIGH PRESSURE QUICKLY BUILDS ACROSS UPPER MI TURING WINDS TO A MORE W DIRECTION. WILL NOT GET TOO SPECIFIC WITH POPS/WX/WINDS FOR WEDNESDAY AFTERNOON ON...AS THERE ARE SEVERAL DISCREPANCIES THAT COULD HAVE SIGNIFICANT IMPACT ON ANY SNOW ACCUMULATIONS. DRY WX SHOULD AGAIN BE THE RULE FOR MOST THURSDAY AFTERNOON THROUGH FRIDAY...EVEN THROUGH NW FLOW ALOFT WILL PUSH A SERIES OF SHORTWAVES THROUGH THE REGION INITIALLY THURSDAY NIGHT. INCREASED CLOUD COVER WILL BE THE MAIN RESULT...AS HIGH PRESSURE BUILDS IN AT THE SFC AND ALOFT. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 1239 AM EST MON NOV 4 2013 VFR CONDITIONS SHOULD PREVAIL THROUGH MON MORNING WITH ALL SITES SEEING INCREASING WINDS DUE TO A TIGHTENING PRESSURE GRADIENT AHEAD OF A LOW MOVING THROUGH SOUTHERN CANADA. WILL MENTION LLWS AT KCMX BUT OTHERWISE GUSTY WINDS AT SFC FOR BOTH KIWD AND KSAW SHOULD PRECLUDE MENTION OF LLWS THERE FOR THE OVERNIGHT HRS. ONCE MIXING COMMENCES ON MONDAY MORNING...EXPECT THE SITES TO QUICKLY BECOME GUSTY WITH GUSTS IN THE 25-30KT RANGE. THERE WILL LIKELY BE SOME RAIN SHOWERS OVER WESTERN TAF SITES BY MON AFTERNOON AS CIGS LOWER TO MVFR FOR A TIME. SHRA ARE MORE UNCERTAIN AT KSAW SO WILL JUST MENTION VCSH THERE TOWARD MON EVENING. MODELS ARE HINTING THAT THERE COULD BE SOME MVFR CLOUDS AFFECTING KSAW LATE TONIGHT AND MONDAY...BUT CONFIDENCE IS TOO LOW TO MENTION ANYTHING MORE THAN SCATTERED LAYER AT THIS TIME. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 458 AM EST MON NOV 4 2013 A TIGHTENING PRESSURE GRADIENT BETWEEN A HIGH MOVING EAST THROUGH QUEBEC AND A LOW SLIDING EAST THROUGH SOUTHERN SASKATCHEWAN HAS LED TO INCREASING SOUTHERLY FLOW ACROSS LAKE SUPERIOR TODAY. SOUTHERLY GALES TO 35-40KTS ARE EXPECTED OVER THE EASTERN HALF OF THE LAKE WHERE GALE WARNING ARE POSTED. AS THE LOW MOVES FROM LAKE WINNIPEG TO HUDSON BAY ON TONIGHT...IT WILL DRAG A TROUGH ACROSS LAKE SUPERIOR AND BRING AN END TO THE GALES DURING THE OVERNIGHT HOURS. WINDS WILL STILL BE GUSTY OUT OF THE SOUTHWEST ON TUESDAY MORNING (TO 30KTS)...BUT THEN WILL QUICKLY DIMINISH TUESDAY EVENING AS A LOW TAKES SHAPE OVER THE CENTRAL PLAINS. THIS LOW WILL TRACK NORTHEAST THROUGH NORTHERN LAKE MICHIGAN ON WEDNESDAY AFTERNOON AND EVENING...BUT AT THIS POINT WINDS ON THE BACK SIDE OF THE LOW ARE EXPECTED TO STAY BELOW 30KTS. A HIGH PRESSURE RIDGE WILL SLIDE INTO THE AREA ON THURSDAY AFTERNOON AND REMAIN THROUGH FRIDAY...KEEPING WINDS BELOW 25KTS. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... GALE WARNING UNTIL MIDNIGHT EST TONIGHT FOR LSZ266-267. GALE WARNING UNTIL 7 PM EST THIS EVENING FOR LSZ244-245-264-265. GALE WARNING FROM 10 AM THIS MORNING TO 7 PM EST THIS EVENING FOR LSZ249>251. LAKE MICHIGAN... GALE WARNING UNTIL 10 PM EST THIS EVENING FOR LMZ221-248-250. && $$ SHORT TERM...VOSS LONG TERM...KF AVIATION...07/VOSS MARINE...VOSS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
458 AM EST MON NOV 4 2013 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 458 AM EST MON NOV 4 2013 WATER VAPOR LOOP AND RAP ANALYSIS SHOWS A SERIES OF SHORTWAVES UPSTREAM...ONE OVER SOUTHERN SASKATCHEWAN...A SECOND OVER THE CENTRAL PLAINS...A THIRD OVER THE COLORADO ROCKIES...A FOURTH DIGGING INTO THE CA COASTLINE AND A FIFTH DIVING THROUGH THE PAC NW. THE INITIAL SHORTWAVE OVER THE CENTRAL PLAINS AND ASSOC STRONG WAA/ISENTROPIC LIFT AHEAD OF THIS FEATURE IS PRODUCING RADAR RETURNS FROM ERN IA NORTH INTO WRN LAKE SUPERIOR/WRN UPPER MI. MUCH OF THE RADAR REFLECTIVITY HOWEVER IS RESULTING IN LITTLE IF ANY PCPN AT SFC THUS FAR AS NOTED ON OBS UPSTREAM. THE SHORTWAVES OVER SCNTRL CANADA AND THE ROCKIES WILL HELP PROPEL A COLD FRONT THROUGH THE FCST AREA TONIGHT AS THEY LIFT NE TOWARD HUDSON BAY. THE WRN CONUS SHORTWAVES WILL EVENTUALLY CONGEAL AND PUSH A PROGRESSIVE POSITIVE TILT TROF AND ASSOC SFC LOW THROUGH THE GREAT LAKES BY MIDWEEK. TODAY...CONTINUED ISENTROPIC ASCENT AND COLUMN MOISTENING THROUGH THE MORNING HRS WILL EVENTUALLY ALLOW PCPN TO BE REALIZED AT THE SFC. THE BEST FORCING WILL BE ALONG A CORRIDOR AHEAD OF AN APPROACHING COLD FRONT WHICH WILL REACH INTO THE WRN THIRD OF UPPER MI. WILL MAINTAIN HIGH CHC TO LIKELY POPS FOR SHRA OVER THESE COUNTIES AND THEN TAPER POPS BACK TO LOW CHC OVER CENTRAL COUNTIES TO SLIGHT CHC OVER FAR EAST FARTHEST AWAY FROM BEST FORCING. TIGHTENING SRLY GRADIENT AHEAD OF THE APPROACHING FRONTAL SYSTEM WILL ALLOW WINDS TO GUST NEAR 40 MPH AT TIMES OVER THE ERN HALF OF THE FCST AREA THIS AFTERNOON. EXPECT TEMPS TO REACH INTO THE UPPER 40S TO AROUND 50F UNDER MOSTLY CLOUDY SKIES. TONIGHT...AS THE WELL-DEFINED SHORTWAVE NOW OVER THE CENTRAL PLAINS LIFTS THROUGH THE NRN PLAINS THIS AFTERNOON AND THEN NORTH OF LAKE SUPERIOR TONIGHT...IT WILL PROPEL THE ASSOCIATED COLD FRONT OVER THE NRN PLAINS INTO THE WEST HALF OF UPPER MI THIS EVENING AND THEN THROUGH THE REST OF UPPER MI LATE TONIGHT. WITH THIS SHORTWAVE LIFTING WELL N OF THE AREA AND WITH THE NEXT SHORTWAVE STILL OVER THE ROCKIES IN THE BASE OF THE WRN CONUS TROF...EXPECT A DRYING TREND ALONG THE FRONTAL BOUNDARY LATE TONIGHT INTO TUE AS FORCING ALONG BOUNDARY FALLS APART. WILL CONTINUE TO TREND POPS DOWN TO SCHC WITH TIME ALONG FRONT TONIGHT AND EXPECT DRY CONDITIONS FOR THE CWA BY 06Z OR SHORTLY THEREAFTER. MIN TEMPS TONIGHT WILL BE COOLEST OVER THE WRN INTERIOR (UPPER 20S TO AROUND 30F) WHERE LONGEST PD OF CLEARING IS EXPECTED BEHIND THE FRONT. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 458 AM EST MON NOV 4 2013 WILL START OFF TUESDAY MORNING UNDER QUICK SW FLOW ALOFT...WITH A RIDGE STUCK ACROSS THE FAR SE STATES AND THE MAIN 500MB LOW ACROSS MANITOBA AND FAR N ONTARIO...WITH A SIGNIFICANT TROUGH EXTENDING FROM S CENTRAL CANADA THROUGH MT AND AZ TO MEXICO. THE NEARLY STACKED 500MB TO SFC LOW OVER N ONTARIO AT 12Z TUESDAY WILL HAVE A COLD FRONT PUSHED ACROSS E UPPER MI...TETHERED TO THE NEXT SFC LOW SET UP ALONG THE CO/NM BORDER. EXPECT DRY WX INITIALLY...THANKS TO MUCH OF THE ENERGY STUCK TO OUR N...CLOSER TO THE LARGE WRAPPED UP LOW. THIS DRY WEATHER WILL BE SHORT LIVED AS THE SW LOW GETS PUSHED ALONG BY THE PROGRESSIVE POSITIVELY TILTED TROUGH. AS THE 500MB TROUGH PUSHES ACROSS THE CENTRAL PLAINS STATES THE SFC LOW WILL BE KICKED NNE ALONG THE LINGERING WEAK FRONTAL BOUNDARY. THE LOW SHOULD PUSH UP TO S WI BY 12Z WEDNESDAY...ALLOWING A SWATH OF OF MOISTURE TO QUICKLY SLIDE N ACROSS IL AND ON 40-50KT SW 850MB WINDS. COMPARING THE 04/00Z MODELS...THE CANADIAN STILL LOOKS TO BE ON THE SLOWER SIDE WITH THE TRACK OF THE SFC LOW OVER LAKE MI AND LAKE HURON WEDNESDAY AFTERNOON/EVENING. WILL CONTINUE TO MENTION THE POTENTIAL FOR 3 OR MORE INCHES OF SNOW IN THE HWO FOR TUESDAY NIGHT THROUGH WEDNESDAY. WILL KEEP FROM GETTING TOO SPECIFIC AT THIS TIME. WHILE BUFKIT IS SHOWING THE POTENTIAL FOR 4-6IN OF SNOW FROM 00-15Z WEDNESDAY OFF THE NAM...THE GFS IS CLOSER TO 1-2IN OF NEW SNOW. IT CONTINUES TO BE DIFFICULT TO TIME THE END OF THE LAKE EFFECT/LAKE ENHANCED SNOW SHOWERS BEHIND THE EXITING SFC LOW WEDNESDAY NIGHT AND THURSDAY...AS A STRONG RIDGE OF HIGH PRESSURE QUICKLY BUILDS ACROSS UPPER MI. WILL NOT GET TOO SPECIFIC WITH POPS/WX/WINDS FOR WEDNESDAY AFTERNOON ON...AS THERE ARE SEVERAL DISCREPANCIES THAT COULD HAVE SIGNIFICANT IMPACT ON ANY SNOW ACCUMULATIONS. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 1239 AM EST MON NOV 4 2013 VFR CONDITIONS SHOULD PREVAIL THROUGH MON MORNING WITH ALL SITES SEEING INCREASING WINDS DUE TO A TIGHTENING PRESSURE GRADIENT AHEAD OF A LOW MOVING THROUGH SOUTHERN CANADA. WILL MENTION LLWS AT KCMX BUT OTHERWISE GUSTY WINDS AT SFC FOR BOTH KIWD AND KSAW SHOULD PRECLUDE MENTION OF LLWS THERE FOR THE OVERNIGHT HRS. ONCE MIXING COMMENCES ON MONDAY MORNING...EXPECT THE SITES TO QUICKLY BECOME GUSTY WITH GUSTS IN THE 25-30KT RANGE. THERE WILL LIKELY BE SOME RAIN SHOWERS OVER WESTERN TAF SITES BY MON AFTERNOON AS CIGS LOWER TO MVFR FOR A TIME. SHRA ARE MORE UNCERTAIN AT KSAW SO WILL JUST MENTION VCSH THERE TOWARD MON EVENING. MODELS ARE HINTING THAT THERE COULD BE SOME MVFR CLOUDS AFFECTING KSAW LATE TONIGHT AND MONDAY...BUT CONFIDENCE IS TOO LOW TO MENTION ANYTHING MORE THAN SCATTERED LAYER AT THIS TIME. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 458 AM EST MON NOV 4 2013 A TIGHTENING PRESSURE GRADIENT BETWEEN A HIGH MOVING EAST THROUGH QUEBEC AND A LOW SLIDING EAST THROUGH SOUTHERN SASKATCHEWAN HAS LED TO INCREASING SOUTHERLY FLOW ACROSS LAKE SUPERIOR TODAY. SOUTHERLY GALES TO 35-40KTS ARE EXPECTED OVER THE EASTERN HALF OF THE LAKE WHERE GALE WARNING ARE POSTED. AS THE LOW MOVES FROM LAKE WINNIPEG TO HUDSON BAY ON TONIGHT...IT WILL DRAG A TROUGH ACROSS LAKE SUPERIOR AND BRING AN END TO THE GALES DURING THE OVERNIGHT HOURS. WINDS WILL STILL BE GUSTY OUT OF THE SOUTHWEST ON TUESDAY MORNING (TO 30KTS)...BUT THEN WILL QUICKLY DIMINISH TUESDAY EVENING AS A LOW TAKES SHAPE OVER THE CENTRAL PLAINS. THIS LOW WILL TRACK NORTHEAST THROUGH NORTHERN LAKE MICHIGAN ON WEDNESDAY AFTERNOON AND EVENING...BUT AT THIS POINT WINDS ON THE BACK SIDE OF THE LOW ARE EXPECTED TO STAY BELOW 30KTS. A HIGH PRESSURE RIDGE WILL SLIDE INTO THE AREA ON THURSDAY AFTERNOON AND REMAIN THROUGH FRIDAY...KEEPING WINDS BELOW 25KTS. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... GALE WARNING UNTIL MIDNIGHT EST TONIGHT FOR LSZ266-267. GALE WARNING UNTIL 7 PM EST THIS EVENING FOR LSZ244-245-264-265. GALE WARNING FROM 10 AM THIS MORNING TO 7 PM EST THIS EVENING FOR LSZ249>251. LAKE MICHIGAN... GALE WARNING UNTIL 10 PM EST THIS EVENING FOR LMZ221-248-250. && $$ SHORT TERM...VOSS LONG TERM...KF AVIATION...07/VOSS MARINE...VOSS
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
557 PM CST TUE NOV 5 2013 .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 338 PM CST TUE NOV 5 2013 COLD FRONT THAT SWEPT ACROSS THE AREA YESTERDAY HAS BECOME A WARM FRONT THIS AFTERNOON THAT STRETCHES FROM A 1010 MB SFC LOW OVER THE OK PANHANDLE NORTHEAST TO ABOUT SHEBOYGAN IN WISCONSIN. SPLAYED WEST TO EAST ACROSS THE CENTER OF THE MPX CWA IS 1025 MB RIDGE OF HIGH PRESSURE. WE HAVE SEEN SOME VERY DRY AIR BUILD IN AT THE SFC WITH THE HIGH...WITH DEW POINTS ACROSS WRN/CENTRAL MN DOWN INTO THE UPPER TEENS TO LOWER 20S. A 0.5 DEG REFLECTIVITY IMAGE AT 21Z SHOWS THE IMPACT OF THIS DRY LOW LEVEL AIR...WITH A NICE DONUT HOLE AROUND THE MPX RADAR. HOWEVER...REFLECTIVITY SOUTH AND WEST OF THE RDA IS LOWER THAN IT IS EAST AND NORTHEAST...SO YOU CAN GET THE SENSE OF HOW THE ATMOSPHERE IS QUICKLY MOISTENING SOUTH AND WEST OF THE TWIN CITES. REGIONAL RADAR RIGHT NOW SHOWS TWO ENHANCED AREAS OF REFLECTIVITY THIS AFTERNOON AND MOST MODELS SHOW THIS CURRENT TREND OF TWO ENHANCED AREAS OF QPF CONTINUING THROUGH MUCH OF THE EVENT. ONE AREA CAN BE BEST DESCRIBED AS A BLOB OF PRECIPITATION THAT CAN BE FOUND AT 21Z ACROSS MOST OF IOWA. THIS IS ON THE NOSE OF THE LLJ AND ITS ASSOCIATED THE MAIN MOISTURE SURGE. THE SECOND IS A BAND OF RADAR RETURNS THAT STRETCHES FROM NEAR NORTH PLATTE IN CENTRAL NEB...NORTHEAST THROUGH SIOUX FALLS AND CONTINUES ON COMPOSITE REFLECTIVITY NORTHEAST TO REDWOOD FALLS/BUFFALO/CAMBRIDGE AND EVENTUALLY OVER TO THE SPOONER WI AREA. THIS IS IN ASSOCIATION WITH ENHANCED FGEN ALONG WITH SOME CSI CENTERED AROUND 700 MB. YOU CAN SEE THE IMPACTS OF THESE TWO PIECES OF FORCING IN SEVERAL OF THE HI-RES MODELS. FOR INSTANCE...THE 05.18 HRRR SHOWS QPF OF 0.75-1.00 INCHES ACROSS SE MN WITH THE MAIN MOISTURE SURGE...A LULL IN TOTAL QPF FROM MANKATO UP THROUGH HASTINGS WHERE ONLY A QUARTER INCH OF QPF IS INDICATED...WITH THE CSI BAND SHOWING UP FROM REDWOOD FALLS THROUGH MINNEAPOLIS AND UP TOWARD RICE LAKE WHERE RUN TOTAL QPF IS UP MORE IN THE 0.5 INCH RANGE THANKS TO THE ENHANCED FGEN/CSI FORCING. FOR THE WINTER WEATHER ADVISORY...IT IS WHERE THIS FGEN BAND SETS UP THAT WILL RESULT IN THE 3-5 INCH SNOWFALL TOTALS THAT ARE EXPECTED. COUPLE OF THINGS THAT MAKE THIS SNOWFALL FORECAST DIFFICULT ARE NARROW NATURE OF THE EXPECTED FGEN BAND /NOT MUCH MORE THAN 50 MILES WIDE/ ALONG WITH HOW QUICKLY DO THE LOW LEVELS OF THE ATMOSPHERE COOL TO ALLOW RAIN TO CHANGE TO SNOW. ALTHOUGH WE ARE SEEING MANY PLACES IN THE TWIN CITIES WITH TEMPS IN THE 40S...IT IS THOSE DEW POINTS AND THE ATTENDANT WET BULB TEMPERATURES THAT YOU REALLY NEED TO PAY ATTENTION TO. BECAUSE OF THE DRY AIR...SFC WEB BULB TEMPS ARE IN THE LOW TO MID 30S...WHICH MEANS AS THE PRECIP EVAPORATES WE WILL QUICKLY SEE TEMPS FALL OFF TO NEAR THE FREEZING MARK...WITH A RAPID CHANGEOVER TO SNOW EXPECTED WEST OF A BLUE EARTH/WASECA/LADYSMITH LINE SHORTLY AFTER RAIN BEGINS. EAST OF THIS LINE...DEWPS ARE STILL MAINLY IN THE MID 30S. A GOOD EXAMPLE OF THIS RAPID CHANGEOVER WAS LITCHFIELD...WHICH FIRST REPORTED RAIN AT 230 PM AND WAS ALREADY REPORTING SNOW 20 MINUTES LATER. THE SPREAD AMONGST THE MODELS FOR WHERE THE 3-5 INCH BAND SETS UP WAS NOT ALL THAT LARGE...RANGING ON THE 05.12 RUNS FROM BEING CENTERED ALONG THE HENNEPIN/DAKOTA COUNTY LINE WITH THE NAM AND MORE ALONG THE HENNEPIN/WRIGHT COUNTY LINE WITH THE GFS/GEM. HRRR/HOPWRF/MPXWRF/ECMWF BASICALLY SPLIT THE DIFFERENCE BETWEEN THE TWO...AND THE CURRENT FORECAST FAVORS A BLEND OF THESE MODELS. THE ONE AREA IT LOOKS LIKE WILL NEED TO BE WATCHED FOR POSSIBLE WARNING TYPE SNOW /GREATER THAN 6 INCHES/ IS SW MN...WHERE THE SNOW IS ALREADY FLYING AND THE RESIDENCE TIME FOR THE FGEN BAND LOOKS TO BE THE LONGEST. HAVE LEFT THE WINTER WEATHER ADVISORY AS IS...THOUGH WOULD SAY THAT MOST OF MN COULD BE ENDED AROUND 9Z...WITH WI ENDING AT 12Z...ABOUT 3 HOURS AHEAD OF WHAT WE CURRENTLY HAVE. FOR AS MUCH FUN AS WE ARE GOING TO HAVE WITH THE PRECIP TONIGHT...WEDNESDAY IS LOOKING QUIET AND BEAUTIFUL...WITH MOSTLY SUNNY SKIES EXPECTED EVERYWHERE BY THE AFTERNOON. DID FAVOR THE FORECAST HIGHS FOR TOMORROW TOWARD A BLEND OF THE DETERMINISTIC MODELS...WHICH RESULTED IN THE COOLEST TEMPS /WITH HIGHS IN THE UPPER 30S/ ALONG WHERE THE BAND OF SNOW IS EXPECTED FOR TONIGHT. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 338 PM CST TUE NOV 5 2013 FOLLOWING WEDNESDAYS SYSTEM...ANOTHER WEAK CLIPPER SYSTEM RIDES SOUTHEAST IN THE NORTHWEST FLOW OVER THE AREA WEDNESDAY NIGHT. THIS WILL PROVIDE A FEW CLOUDS BUT IS EXPECTED TO MOVE THROUGH DRY. HIGH PRESSURE WILL DOMINATE THE WEATHER FOR THURSDAY...WITH SOME SUNSHINE AND NEAR NORMAL TEMPERATURES. MORE ZONAL FLOW REGIME DEVELOPS AND ANOTHER FAST MOVING TROUGH MOVES INTO THE AREA FOR FRIDAY INTO SATURDAY. THE 12Z ECMWF IS MORE AMPLIFIED WITH THIS TROUGH WHILE THE GFS IS LESS SO AND FARTHER NORTH. THE ECMWF HAS BEEN MORE CONSISTENT WITH THE DEEPER NATURE OF THE TROUGH...SO WILL FOLLOW THIS FOR NOW. STILL PROVIDES JUST A CHANCE OF MIXED TYPE PRECIPITATION FOR THE EVENT...MAINLY OVER THE NORTHERN CWA. LARGE HIGH PRESSURE SYSTEM FOLLOWS THIS TROUGH FOR SUNDAY...WITH THE GFS AND ECMWF DIVERGING ON OVERALL MOVEMENT OF THE NEXT WESTERN TROUGH INTO THE CWA. THE ECWMF IS FASTER WITH A STRONG COLD FRONT SUNDAY NIGHT DRAWING IN MUCH COLDER AIR OVER THE AREA INTO THE FIRST PART OF NEXT WEEK. THE GFS HOLDS OFF ON THIS COLD AIR INTRUSION UNTIL WEDNESDAY. STILL TIME TO DECIPHER MODEL TRENDS WITH THIS OVERALL DEVELOPMENT. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING) ISSUED AT 557 PM CST TUE NOV 5 2013 A BAND OF MODERATE TO HEAVY SNOW FROM KRWF-MGG-KJMR LINES UP WELL WITH THE MID LEVEL FRONTOGENESIS THIS EVENING. THE BAND IS DRIFTING EAST NEAR 10 KNOTS. KSTC IS ON THE NORTH EDGE WITH MVFR CIGS AND LESS THAN MVFR VISIBILITIES THIS EVENING WITH KAXN REMAINING DRY. KRWF WILL LIKELY FLUCTUATE SOME WITH THE VSBY THIS EVENING AS THE SNOW BAND IS BECOMING MORE DIFFUSE HEADING TO THE SOUTHWEST. HOWEVER...CEILINGS UNDER 500 FEET ARE LIKELY THROUGH THE EVENING. THE BAND OF MODERATE TO HEAVY SNOW WILL OVERTAKE KRNH AND KMSP BY 02Z AND PERSIST TO BETWEEN 05Z AND 06Z. CEILINGS WILL DROP QUICKLY TO 500 FEET WITH VSBYS 1/2SM TO 3/4SM. ALTHOUGH RAIN IS FALLING AT KEAU ATTM...CONFIDENCE IS NOT AS HIGH ON WHEN THE CHANGEOVER TO SNOW WILL TAKE PLACE. BASED THE CHANGE TO SNOW AT 04Z FROM THE LATEST NAM WHICH HAS BEEN HANDLING THE QUICK ONSET AND CHANGEOVER THIS AFTERNOON TO OUR SOUTHWEST. A MUCH BETTER DAY AVIATION-WISE ON WEDNESDAY WITH VFR CONDITIONS. KMSP...BAND OF MODERATE SNOW ARRIVING BY 02Z AND LASTING TO 05Z. 1/2SM TO 3/4SM VSBYS WITH CIGS QUICKLY DROPPING TO 500 FEET. SNOW DIMINISHES AFTER MIDNIGHT WITH CEILINGS LIFTING TO MVFR BY 08Z AND VFR BY DAYBREAK. A FINE DAY ON WEDNESDAY WITH NW WINDS NEAR 10 KNOTS. /OUTLOOK FOR KMSP/ THU...VFR. WINDS W 5-10 KTS. FRI...CHC FOR MVFR CIGS AND -RA. WINDS SE 10-15 KTS. SAT...VFR. WINDS NW 10-15 KTS. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...WINTER WEATHER ADVISORY UNTIL 6 AM CST WEDNESDAY FOR MNZ051>053- 059>063-065>070-073>078-082>085-091-092. WI...WINTER WEATHER ADVISORY UNTIL 9 AM CST WEDNESDAY FOR WIZ014>016- 023>025-027. && $$ SHORT TERM...MPG LONG TERM...DWE AVIATION...RAH
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
306 PM CST MON NOV 4 2013 .SHORT TERM...(TONIGHT) ISSUED AT 226 PM CST MON NOV 4 2013 COLD FRONT WILL BE CLEARING THE MPX CWA SHORTLY...TAKING THE WAA RAINFALL THAT DEVELOPED OUT AHEAD OF IT WITH. UPPER WAVE THAT IS DRIVING ALL OF THIS WAS MOVING INTO WC MN THIS AFTERNOON AND WILL BE HEADING FOR NE MN THIS EVENING...SO BATCH OF POST FRONTAL LIGHT RAIN WILL LARGELY STAY NORTH OF THE MPX AREA AFTER MOVING OUT OF WRN MN. SKIES ALREADY CLEARING OUT THIS AFTERNOON AND EXPECT CLEAR SKIES FOR MUCH OF THE NIGHT...WITH HIGH CLOUDS STARTING TO STREAM INTO THE SOUTHWEST AFTER MIDNIGHT. WINDS WILL BECOME QUITE LIGHT...WHICH WILL SET THE STAGE FOR A CHILLY EVENING WITH TEMPERATURES EXPECTED TO FALL OFF INTO THE 20S. THIS WILL GIVE US A GOOD COOL BASE TO START FROM FOR THE POTENTIAL WINTER STORM TO IMPACT THE AREA BEGINNING LATER ON TUESDAY. .LONG TERM...(TUESDAY THROUGH MONDAY) ISSUED AT 226 PM CST MON NOV 4 2013 THE NEXT WAVE TO AFFECT THE REGION WILL LIFT NORTHEAST AS A WEAK SURFACE LOW TRAVELS FROM THE SOUTHWEST TO CENTRAL WISCONSIN BY WEDNESDAY MORNING. 295K ISENTROPIC SURFACE SHOWING STRONG ADIABATIC OMEGA BEING GENERATED INTO SOUTHERN MN AFTER 21Z...LIFTING TO THE METRO AREA THROUGH 00Z.WED. EXPECT RAIN TO DRIFT INTO SOUTHWEST IN THE AFTERNOON...SPREADING INTO EAST CENTRAL MN BY LATE AFTERNOON. PRECIPITATION WILL LIKELY START AS A RAIN/SNOW COMBO BUT WILL RAPIDLY CHANGE OVER TO SNOW SHORTLY AFTER 00Z...AS STRONG LIFT ZONE FROM NEAR REDWOOD FALLS...TO THE TWIN CITIES MOVES IN. APPEARS TO BE A GOOD 4 G/KG SPECIFIC HUMIDITY VALUES AFFECTING THE REGION FOR ABOUT 12 HOURS DURING THE EVENT. STRONG LAYERED FRONTOGENESIS COMBINED WITH DECENT VERTICAL MOTION IN THE DENDRITIC GROWTH LAYER SHOULD YIELD A PERIOD OF MODERATE TO PERHAPS HEAVY SNOW IN THE 00Z-04Z PERIOD OVER EAST CENTRAL MN INTO WEST CENTRAL WISCONSIN...INCLUDING THE METRO. EXPECTING ABOUT A 70 MILE WIDE BAND OF 3-6 INCHES OF WET SNOW FROM SOUTHWEST MN INTO NORTHWEST WISCONSIN. HAVE RESOLVED THE WATCH WITH A SNOW ADVISORY ACROSS THE CENTRAL AND EAST...ENDING BY 12Z WED IN MN AND LINGERING UNTIL 15Z WED FOR WISCONSIN. SYSTEM SHOULD EXIT TO THE EAST BY MIDDAY WEDNESDAY WITH CLEARING EXPECTED THEREAFTER AS SURFACE HIGH BUILDS SOUTHEAST OVER THE NORTHERN PLAINS. ANOTHER WEAK TROUGH TRAILS THIS SYSTEM AND WILL SPREAD SOME CLOUDS OVER THE AREA INTO THURSDAY...BUT IT SHOULD REMAIN COOL AND DRY. THE LONG TERM MODELS CONTINUE TO SHOW ANOTHER DECENT SHORT WAVE TROUGH TO SPREAD EAST IN MORE WESTERLY FLOW PATTERN DEVELOPING LATE IN THE WEEK. BOTH THE GFS AND ECMWF DEVELOP A SURFACE LOW OVER THE NORTHERN PLAINS AND MOVE IT EAST ACROSS MINNESOTA FRIDAY INTO SATURDAY. THE GFS IS A BIT COOLER AND DEVELOPS SNOW OVER THE FAR NORTHERN CWA BY SATURDAY MORNING. WILL HAVE TO MONITOR THIS SYSTEM FOR THE POSSIBILITY OF MORE SNOW AFFECTING AT LEAST A PORTION OF THE AREA. A LARGE HIGH FOLLOWS THIS SYSTEM AND SHOULD PROVIDE A COOL AND DRY PERIOD INTO NEXT WEEK. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 1203 PM CST MON NOV 4 2013 COLD FRONT PUSHING INTO THE WRN TWIN CITIES METRO AT 18Z. WARM AIR ADVECTION OUT AHEAD OF IT HAS RESULTED IN A SHIELD OF LGT-MOD RA WITH MVFR CIGS DEVELOPING ACROSS ERN MN. PRECIP BACK ACROSS WRN MN IS IN ASSOCIATION WITH THE UPPER WAVE...WHICH IS HEADING FOR NE MN THIS AFTERNOON. HRRR HAS DONE AN EXCELLENT JOB IN HANDLING PRECIP SO FAR TODAY...SO FOLLOWED IT CLOSELY IN TAFS. USED THE HRRR/RAP TO TIME CIG IMPROVEMENTS THROUGH. WINDS BEHIND THE COLD FRONT HAVE BEEN TURNING RATHER QUICKLY OVER TO THE WNW...SO VEERED WINDS A BIT MORE THAN WHAT GFSLAMP HAS. THIS EVENING...SKIES WILL CLEAR AND WINDS BECOME LGT AND VRB...WITH NEXT BATCH OF PRECIP HEADING FOR THE MPX AREA AT THE TAIL END OF THE TAF. PRECIP WILL MOVE INTO THE RWF AREA VERY CLOSE TO 18Z...WITH BOTH THE NAM/GFS SHOW A PRECIP START TIME OF 21Z FOR MSP. HAVE A MIX FOR MSP RIGHT NOW...BUT THIS TAF PERIOD COULD VERY EASILY CLOSE OUT WITH HEAVY SNOW FALLING...LOTS OF TIME TO REFINE THAT TIMING THOUGH. KMSP...CIGS FOR A TIME MAY BE LOWER THAN INDICATED IN TAF FOR THE FIRST HOUR...BUT CONDS SHOULD QUICKLY IMPROVE...ESPECIALLY AFTER 20Z. MAJORITY OF PERIOD WILL HAVE FEW ISSUES UNTIL THE VERY END...AS PRECIP RAPIDLY APPROACHES THE FIELD FROM THE SOUTH. FOR NOW...HAVE A RASN MIX...BUT THE NAM CONTINUES TO SHOW SN BEING THE PREDOMINATE P-TYPE...SO MAY HAVE MOD SNOW ALREADY BY 00Z TUE EVENING. /OUTLOOK FOR KMSP/ TUE NGT...IFR AND LOWER WITH SN/+SN THRU 8Z. 3-5 IN POSSIBLE. WED...VFR. WINDS NW 10 KTS. THU...VFR. WINDS W 5 KTS. FRI...MVFR WITH CHC -RA. WINDS SE 10 KTS. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...WINTER WEATHER ADVISORY FROM 4 PM TUESDAY TO 6 AM CST WEDNESDAY FOR MNZ051>053-059>063-065>070-073>078-082>085-091-092. WI...WINTER WEATHER ADVISORY FROM 6 PM TUESDAY TO 9 AM CST WEDNESDAY FOR WIZ014>016-023>025-027. && $$ SHORT TERM...MPG LONG TERM...DWE AVIATION...MPG
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
1219 PM CST MON NOV 4 2013 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 255 AM CST MON NOV 4 2013 SHORTWAVE ENERGY IN THE BASE OF THE MID/UPPER LOW OVER SOUTHERN SASKATCHEWAN/MANITOBA WILL ROTATE OVER THE AREA TODAY. THE BEST FEED OF 850-700MB MOISTURE CONVERGENCE IS PROGGED FROM SOUTHEAST MN ACROSS NORTHWESTERN WI...WHERE LIKELY POPS HAVE BEEN INCLUDED BETWEEN 15Z AND 21Z AS A DECENT POCKET OF 700MB OMEGA PASSES. PRECIP AMOUNTS WILL BE LIGHT...GENERALLY ONE TO TWO TENTHS OF AN INCH OR LESS....ENDING BY 00Z TUESDAY. WINDS WILL BE BREEZY TODAY AHEAD OF THE COLD FRONT...AS TEMPERATURES TOP OUT IN THE MID 40S TO LOWER 50S. LOWS TONIGHT WILL FALL INTO THE UPPER 20S AND LOWER 30S AS WINDS DECREASE AND CLOUDS SCATTER OUT. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 255 AM CST MON NOV 4 2013 SOUTHERN MN AND AREAS OF WC WI WILL GET SNOWFALL TUESDAY AFTN...THRU WEDNESDAY MORNING. THE MAIN PROBLEMS ARE WHETHER DRIER AIR FROM THE NORTH WILL FORCE THE HEAVIER QPF AMTS TO THE SE OF MN...LIMITING SNOWFALL AMTS ONCE THE CHG OVER DEVELOPS...OR WILL THE ATMOSPHERE BE TOO WARM WHERE THE HEAVIER QPF AMTS ARE LOCATED...AND AGAIN DECREASING THE SNOWFALL AMTS. TEMPS IN THE LOWER 1 KM OF THE ATMOSPHERE WILL BE CRITICAL ALONG WITH THE ORIENTATION OF THE 92/85H WINDS WHICH WILL ADVECT DRIER AIR FROM NORTHERN MN TUE/TUE EVENING. CURRENT MODELS ARE HOLDING ONTO A SCENARIO OF BOTH THE HIGHER RH VALUES AND TEMPS BETWEEN 92-85H ARND -2 TO -4C ALONG A KRWF TO KMSP TO KRCX LINE DURING THE CRITICAL TIME FRAME OF ENHANCED OMEGA/S. ONLY PROBLEM WITH SNOWFALL AMTS WOULD BE THE TIME FRAME WHERE BOTH THE MAX OMEGA IN THE CRITICAL -12 TO -18C DENDRITIC ZONE IS BETWEEN 18Z TUE TO 03Z WED. USUALLY IF THE PRECIPITATION STARTS OUT AS RAIN DURING THE ONSET OF THE EVENT DURING THE AFTN TIME PERIOD /TEMPS NEAR THE SFC ABV FREEZING/ LITTLE OR NO SNOWFALL WILL ACCUMULATE. THEREFORE KEEPING TOTAL SNOWFALL AMTS LOWER THAN EXPECTED BY THE TIME THE EVENT ENDS EARLY WEDNESDAY MORNING. THE ONLY WAY TO SUPPLEMENT HIGHER SNOWFALL AMTS WOULD BE TO LOWER TEMPS TO BLW FREEZING IN THE AFTN...START THE PRECIPITATION EARLIER IN THE DAY...KEEPING TEMPS LOWER THAN FORECASTED...OR HAVE AN ADDITION FOR THE PRODUCTION OF HIGHER SNOWFALL RATES. THE ONLY PLAUSIBLE SCENARIO FOR THIS SYSTEM WOULD BE THE HIGHER SNOWFALL RATES IN THE FORM OF UPRIGHT CONVECTION ALONG THE SLOPING FRONTAL BOUNDARY...OR CSI /SLANTWISE CONVECTIVE INSTABILITY/. EC DOES NOT HAVE ANY TYPE OF CSI OR ANY CONVECTIVE NATURE TO THIS SYSTEM...AND THE LATEST GFS HAS LITTLE AND MAINLY TO THE SE OF OUR CWA. THEREFORE...THIS SCENARIO CAN BE TAKEN OUT FOR HEAVIER SNOWFALL RATES. THE BEST SCENARIO WOULD BE AN AREA OF 3 TO 5 INCHES FROM KRWF TO KMSP TO KRCX WITH LOCALLY 6 INCHES NEAR KRWF WHERE SOME ENHANCED HIGHER QPF AMTS ARE LOCATED TUESDAY AFTN. ANOTHER FACTOR THAT MAY INFLUENCE HIGHER QPF AMTS...AND ADD TO HEAVIER SNOWFALL WOULD BE THE INTERACTION OF HIGHER PWATS FROM THE DECAYING TROPICAL SYSTEM MOVING ACROSS MEXICO EARLY THIS MORNING. THIS COULD TRANSPORT HIGHER PWATS INTO THE SYSTEM TUESDAY. TOO MANY DETAILS TO SORT OUT...SO WILL CONTINUE THE WINTER STORM WATCH. BY WED AFTN...THE MAIN 50H TROUGH WILL HAVE MOVED THRU THE UPPER MIDWEST...CUTTING OFF PRECIPITATION AND DECREASING CLOUD COVER. BY THE END OF THE WEEK...AND INTO THE WEEKEND...THE PATTERN WILL SHIFT SLIGHTLY AND BECOME MORE ZONAL LEAVING TO SEVERAL FAST MOVING SHRTWV/S AND PRECIPITATION CHC/S. THE FIRST SYSTEM WILL BE COLD ENOUGH TO BEGIN AS SNOW...BUT QUICKLY CHG OVER TO RAIN FOR MOST OF SOUTHERN MN FRIDAY AFTN. NEXT WEEK LOOKS TO BE MUCH WARMER AS THE PATTERN BECOMES MORE WSW AND A PACIFIC TYPE AIR MASS TAKES OVER. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 1203 PM CST MON NOV 4 2013 COLD FRONT PUSHING INTO THE WRN TWIN CITIES METRO AT 18Z. WARM AIR ADVECTION OUT AHEAD OF IT HAS RESULTED IN A SHIELD OF LGT-MOD RA WITH MVFR CIGS DEVELOPING ACROSS ERN MN. PRECIP BACK ACROSS WRN MN IS IN ASSOCIATION WITH THE UPPER WAVE...WHICH IS HEADING FOR NE MN THIS AFTERNOON. HRRR HAS DONE AN EXCELLENT JOB IN HANDLING PRECIP SO FAR TODAY...SO FOLLOWED IT CLOSELY IN TAFS. USED THE HRRR/RAP TO TIME CIG IMPROVEMENTS THROUGH. WINDS BEHIND THE COLD FRONT HAVE BEEN TURNING RATHER QUICKLY OVER TO THE WNW...SO VEERED WINDS A BIT MORE THAN WHAT GFSLAMP HAS. THIS EVENING...SKIES WILL CLEAR AND WINDS BECOME LGT AND VRB...WITH NEXT BATCH OF PRECIP HEADING FOR THE MPX AREA AT THE TAIL END OF THE TAF. PRECIP WILL MOVE INTO THE RWF AREA VERY CLOSE TO 18Z...WITH BOTH THE NAM/GFS SHOW A PRECIP START TIME OF 21Z FOR MSP. HAVE A MIX FOR MSP RIGHT NOW...BUT THIS TAF PERIOD COULD VERY EASILY CLOSE OUT WITH HEAVY SNOW FALLING...LOTS OF TIME TO REFINE THAT TIMING THOUGH. KMSP...CIGS FOR A TIME MAY BE LOWER THAN INDICATED IN TAF FOR THE FIRST HOUR...BUT CONDS SHOULD QUICKLY IMPROVE...ESPECIALLY AFTER 20Z. MAJORITY OF PERIOD WILL HAVE FEW ISSUES UNTIL THE VERY END...AS PRECIP RAPIDLY APPROACHES THE FIELD FROM THE SOUTH. FOR NOW...HAVE A RASN MIX...BUT THE NAM CONTINUES TO SHOW SN BEING THE PREDOMINATE P-TYPE...SO MAY HAVE MOD SNOW ALREADY BY 00Z TUE EVENING. /OUTLOOK FOR KMSP/ TUE NGT...IFR AND LOWER WITH SN/+SN THRU 8Z. 3-5 IN POSSIBLE. WED...VFR. WINDS NW 10 KTS. THU...VFR. WINDS W 5 KTS. FRI...MVFR WITH CHC -RA. WINDS SE 10 KTS. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...WINTER STORM WATCH FROM TUESDAY AFTERNOON THROUGH LATE TUESDAY NIGHT FOR MNZ045-051>053-058>063-065>070-073>078-082>085- 091-092. WI...WINTER STORM WATCH FROM TUESDAY AFTERNOON THROUGH LATE TUESDAY NIGHT FOR WIZ014>016-023>025-027. && $$ SHORT TERM...LS LONG TERM...JLT AVIATION...MPG
AREA FORECAST DISCUSSION...UPDATED
NWS ST LOUIS MO
953 PM CST Tue Nov 5 2013 .UPDATE: Issued at 940 PM CST Tue Nov 5 2013 Tonight`s rain event is unfolding about as expected. Have made tweaks to bring categorical pops further north and east more quickly, but the general forecast is about the same. Should see the rain overspread the rest of the area through the 06-08Z as moderate to strong isentropic lift continues on the nose of the low level jet. Am monitoring the line of thunderstorms now in southeast Kansas to possibly bring thunder to the southern 1/2 of the CWFA. RAP forecasts up to 100 J/kg MUCAPE moving in ahead of the front so I can`t rule it out. However, lightning strikes are relatively few and far between right now and am thinking that ongoing rain will be enough to dampen any instability. Will leave mention of thunder out for now and continue to monitor. Carney && .SHORT TERM: (Through Wednesday) Issued at 205 PM CST Tue Nov 5 2013 Main shield of rain from this morning has lifted north as forecast, with only small batches of light rain and sprinkles streaming northeast within the warm sector. Low pressure currently located in north central Kansas will continue to advance northeast along the stalled front into Iowa and Wisconsin tonight. Trailing cold front will sweep east across Missouri and Illinois late tonight and Wednesday with a period of rain and falling temperatures expected. CVKING .LONG TERM: (Wednesday Night through Next Tuesday) Issued at 205 PM CST Tue Nov 5 2013 Pattern flattens out in the wake of this system with a dry and seasonal forecast remaining in tact despite a frontal passage on Saturday. Precipitation chances may eventually increase next week if better moisture can return ahead of a front poised to move across the Midwest on Monday. CVKING && .AVIATION: (For the 00z TAFs through 00z Wednesday Evening) Issued at 610 PM CST Tue Nov 5 2013 Deep low level moisture advecting N in advance of the storm system and cold front will mean widespread MVFR/IFR cigs overnight, along with MVFR/occasional IFR vsbys in occasional rain. Leadings edge of the lower cigs is currently near an KUNO-KHAE line, and expect a further deterioration of cigs in this area as we head into the evening with IFR dominating for much of the night. However, low level condensation pressure deficits indicate that the IFR development in STL area may hold off until after midnight. Several waves of rain are anticipated, and have used a combo of latest radar trends and HRRR output for timing of precip. Thunder isn`t out of the question, but at this time it looks like it would be very isolated so have left out of TAF forecasts attm. Lowest conditions...IFR with cigs aob 400 ft and vsbys aob 2sm...should occur with fropa on Wednesday morning. However, there should be a fairly rapid improvement several hours after fropa as rain winds down and as drier air surges east, with MVFR cigs returning about 3 hours after the passage of front. Specifics for KSTL: Deteriorating conditions are forecast over the TAF area this evening, and while MVFR cigs and a bit of light rain is expected to dominate it now appears that a drop to IFR cigs and persistent rainfall will hold off until after 05z. However, IFR cigs and MVFR/occasional IFR vsbys in rain are expected to dominate during the predawn hours and into Wednesday morning, with the lowest conditions tied to fropa around 15z. Expect a rapid improvement several hours after fropa, with rain ending and MVFR cigs returning by around 18z. Truett && .LSX WATCHES/WARNINGS/ADVISORIES: MO...NONE. IL...NONE. && $$ WFO LSX
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
614 PM CST Tue Nov 5 2013 .SHORT TERM: (Through Wednesday) Issued at 205 PM CST Tue Nov 5 2013 Main shield of rain from this morning has lifted north as forecast, with only small batches of light rain and sprinkles streaming northeast within the warm sector. Low pressure currently located in north central Kansas will continue to advance northeast along the stalled front into Iowa and Wisconsin tonight. Trailing cold front will sweep east across Missouri and Illinois late tonight and Wednesday with a period of rain and falling temperatures expected. CVKING .LONG TERM: (Wednesday Night through Next Tuesday) Issued at 205 PM CST Tue Nov 5 2013 Pattern flattens out in the wake of this system with a dry and seasonal forecast remaining in tact despite a frontal passage on Saturday. Precipitation chances may eventually increase next week if better moisture can return ahead of a front poised to move across the Midwest on Monday. CVKING && .AVIATION: (For the 00z TAFs through 00z Wednesday Evening) Issued at 610 PM CST Tue Nov 5 2013 Deep low level moisture advecting N in advance of the storm system and cold front will mean widespread MVFR/IFR cigs overnight, along with MVFR/occasional IFR vsbys in occasional rain. Leadings edge of the lower cigs is currently near an KUNO-KHAE line, and expect a further deterioration of cigs in this area as we head into the evening with IFR dominating for much of the night. However, low level condensation pressure deficits indicate that the IFR development in STL area may hold off until after midnight. Several waves of rain are anticipated, and have used a combo of latest radar trends and HRRR output for timing of precip. Thunder isn`t out of the question, but at this time it looks like it would be very isolated so have left out of TAF forecasts attm. Lowest conditions...IFR with cigs aob 400 ft and vsbys aob 2sm...should occur with fropa on Wednesday morning. However, there should be a fairly rapid improvement several hours after fropa as rain winds down and as drier air surges east, with MVFR cigs returning about 3 hours after the passage of front. Specifics for KSTL: Deteriorating conditions are forecast over the TAF area this evening, and while MVFR cigs and a bit of light rain is expected to dominate it now appears that a drop to IFR cigs and persistent rainfall will hold off until after 05z. However, IFR cigs and MVFR/occasional IFR vsbys in rain are expected to dominate during the predawn hours and into Wednesday morning, with the lowest conditions tied to fropa around 15z. Expect a rapid improvement several hours after fropa, with rain ending and MVFR cigs returning by around 18z. Truett && .LSX WATCHES/WARNINGS/ADVISORIES: MO...NONE. IL...NONE. && $$ WFO LSX
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
900 PM CST TUE NOV 5 2013 .UPDATE... WITH SNOW PRETTY MUCH DISSIPATING ACROSS NORTHEAST NEBRASKA...HAVE CANCELLED THE WINTER WEATHER ADVISORY. THERE COULD BE SOME LIGHT SNOW THERE LATER THIS EVENING OR OVERNIGHT AS DEFORMATION ZONE ROTATES IN FROM NORTH CENTRAL NEBRASKA...BUT WOULD EXPECT THIS AREA TO DIMINISH AS IT MOVES EAST. ALSO...ADDITIONAL AMOUNTS SHOULD BE MINIMAL. DERGAN && PREV DISCUSSION... /ISSUED 534 PM CST TUE NOV 5 2013/ AVIATION...00Z TAFS FOR KOFK...KLNK AND KOMA. IFR CONDITIONS WILL CONTINUE AT ALL TAF SITES THROUGH ABOUT 14Z. LARGE AREA OF PRECIPITATION WILL GRADUALLY SHIFT EAST OF THE AREA BY 08Z...HOWEVER LOW CLOUDS BELOW FL010 WILL REMAIN. VSBYS WILL BE VARIABLE BETWEEN 2 AND 5SM...WITH DRIZZLE POSSIBLE BETWEEN MAIN RAIN/SNOW AREAS. THE RAIN/SNOW LINE WILL REMAIN NORTHWEST OF THE KOMA AND KLNK AREAS THROUGH THE NIGHT...BUT A MIX OF RAIN AND SNOW COULD OCCUR AT THOSE SITES AS THE PRECIPITATION WINDS DOWN. IFR CIGS SHOULD GRADUALLY LIFT TO MVFR AROUND 14Z...WITH VFR CONDITIONS EXPECTED SOMETIME AFTER 20Z. DERGAN PREV DISCUSSION... /ISSUED 303 PM CST TUE NOV 5 2013/ SHORT TERM...TONIGHT THROUGH FRIDAY. UPPER TROUGH TO OUR WEST CONTINUES TO WORK SLOWLY EAST PER AFTERNOON STLT IMAGERY. THIS SYSTEM HAS BEEN VERY EFFICIENT IN GENERATING PRECIP ACROSS THE FORECAST AREA TODAY...SOME LIQUID AMOUNTS HAVE PUSHED PAST 1 INCH...AS IT PRODUCED DECENT FRONTOGENETICAL FORCING WHICH TAPPED DECENT LOWER LEVEL MOISTURE. THIS IS/WAS DESPITE ANEMIC UPPER HGT FALLS...20-40M AT H5. SHORT TERM QPF FROM 4KM WRF/RAP AND HRRR CONTINUE TO LIFT PRECIP ENE WITH IT EXITING SWRN ZONES NOT TOO LONG AFTER THE 00Z-03Z TIME PERIOD WITH A DEFORMATION BAND OF DWINDLING PRECIP PROBABLY LINGERING OVER NERN NEBR ALL NIGHT AND POSSIBLY SOME TRACE FLURRIES YET IN THE MORNING. BASED ON CURRENT STLT/RADAR TRENDS THIS LOOKS REASONABLE. WILL LEAVE WINTER WEATHER HEADLINE ALONE FOR THIS EVENING ALTHOUGH ACCUMULATIONS THUS FAR ON SERN EDGE OF ADVISORY HAVE BEEN MOSTLY LIMITED TO GRASSY SURFACES AND GENERALLY LESS THAN FORECAST DUE TO WARM GROUND AND SFC TEMPS AT OR A LITTLE ABOVE FREEZING. WITH APPROACHING NIGHTFALL...SNOW ACCUMULATIONS SHOULD BE A LITTLE MORE EASILY TO COME BY BUT MOST ADDITIONAL SHOULD BE AN INCH OR TWO...OR LESS...AFT 00Z. THE RAIN/SNOW MIX MAY MAKE IT TO OMAHA/LINCOLN BUT IT APPEARS COLDER AIR SUPPORTING THE CHANGEOVER WILL BE ARRIVING ABOUT THE SAME TIME THE PRECIP ENDS AT THOSE CITIES. OTHERWISE...FORECAST IN THE SHORTER TERM IS MAINLY TEMPERATURE DRIVEN AND LITTLE CHANGES WERE MADE TO FORECAST HIGHS WED THROUGH FRIDAY. DID BUMP THEM UP A FEW DEGREES SOUTH ON WED WHERE GROUND WILL BE ABSENT ANY SNOW AS WIND DIRECTION...NW SHIFTING TO WSW WILL BE FAVORABLE FOR MIXING. BUT IF CLOUDS FAIL TO CLEAR...WHICH WAS NOT EXPECTED...HIGHS WOULD BE A BIT COOLER. ANY RESIDUAL SNOW COVER WILL HAVE A DWINDLING IMPACT ON HIGHS THURSDAY AND ESPECIALLY BY FRIDAY NORTH...WHICH WAS REFLECTED IN PREV FORECAST AND LOOKED GOOD BASED ON LATEST FORECAST SOUNDINGS. MAIN CHANGE BEYOND WEDNESDAY WAS TO LOWER LOWS A CATEGORY OR SO THURSDAY NIGHT ESPECIALLY E...AS RETURN FLOW WILL PROBABLY SET UP TOO LATE TO KEEP MANY TEMPS FROM DROPPING TOWARD THE MID/UPPER 20S THAT GUIDANCE FORECAST. CHERMOK LONG TERM...FRIDAY NIGHT THROUGH TUESDAY. MEDIUM RANGE MODELS LEAVE LITTLE TO BE DESIRED IN THE EXTENDED PDS WITH GREAT VARIATION SEEN BTWN THE ECM/GFS/CMC. THUS MAKING TEMP FCST AS WELL AS POTENTIAL PCPN MON NIGHT/TUES EXTREMELY PROBLEMATIC AT BEST. AS OF NOW...LATEST ECM PROGS LARGE SCALE FLOW TRANSITIONING FROM ZONAL TO DEVELOPING TWO SIGNIFICANT SHORTWAVE TROFS...ONE OVER THE PAC NW AND THE OTHER OVER THE GREAT LAKES THUS FAVORING A COLD PATTERN ACROSS THE CNTRL CONUS. THE GFS ON THE OTHER BASICALLY MAINTAINS RELATIVELY ZONAL FLOW. MEANWHILE THE CMC DIGS AN UPPER TROF THRU THE GREAT BASIN WITH SW FLOW ALOFT PREVAILING. COMPARISON OF MAX/MIN TEMPS BTWN THE 05/00Z ECMMOS AND 05/12Z MEX CLEARLY SHOWING THE DISTINCTION. HIGHS PROGGED NEXT TUES AT KOMA...ECM MOS 36/MEX 49. GIVEN THAT THE ECM HAS PROVEN TO OUT PERFORM ON A REGULAR BASIS...FEEL COMPELLED TO TREND TOWARD THE COOLER SOLUTION. AS FOR POSSIBLE PCPN MON NIGHT/TUES...WILL AGAIN OPT TO GO WITH THE DRIER ECM. DEE && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && $$ 99/99
AREA FORECAST DISCUSSION
NWS HASTINGS NE
813 PM CST TUE NOV 5 2013 .UPDATE... ISSUED AT 813 PM CST TUE NOV 5 2013 AS OF 02Z...RADAR RETURNS FROM KUEX INDICATE LITTLE IF ANY PRECIPITATION IS OCCURRING ACROSS OUR CWA. WATER VAPOR IMAGERY AND RAP DATA SUGGEST THE 700MB MID LEVEL SHORTWAVE TROUGH AXIS IS DIRECTLY OVERHEAD OUR CWA AT THIS HOUR...AND QUICKLY DEPARTING TO THE NORTHEAST. RADAR DATA FROM KLNX DOES INDICATE LIGHT PRECIPITATION OVER NORTH CENTRAL NEBRASKA...THE RESULT OF SUBTLE MID LEVEL DEFORMATION TO THE NORTHWEST OF THE MID LEVEL TROUGH AXIS. SOME OF THIS ACTIVITY COULD BRIEFLY MOVE ACROSS NORTHERN PORTIONS OF OUR CWA IN THE FORM OF LIGHT SNOW THROUGH 06Z. THAT BEING SAID...VERY LITTLE IF ANY SNOW ACCUMULATION IS EXPECTED WITH THIS ACTIVITY AND AS A RESULT...THE WINTER WEATHER ADVISORY...WHICH WAS IN EFFECT ACROSS OUR EXTREME NORTHWEST...WAS CANCELLED. UPDATED FORECAST GRIDS TO REMOVE POPS THROUGH THE REMAINDER OF THE NIGHT. THE GOING FORECAST WAS IN GREAT SHAPE OTHERWISE...WITH ONLY A FEW ADDITIONAL TWEAKS MADE TO HOURLY TEMPERATURE...SKY...WIND...AND DEW POINT GRIDS TO BETTER REFLECT CURRENT OBSERVATIONS. && .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 255 PM CST TUE NOV 5 2013 THE PRECIPITATION EVENT TODAY IS GENERALLY UNFOLDING AS EXPECTED WITH WIDESPREAD RAINFALL DURING THE MORNING...AND A CHANGE TO SNOW IN OUR W/NW BY MID/LATE MORNING. SEVERAL LOCATIONS PICKED UP AT LEAST ONE HALF OF AN INCH WHILE OTHER REPORTS OF OVER ONE INCH HAVE BEEN RECEIVED. THE RAIN HAS MIXED WITH AND MADE THE SWITCH TO SNOW FROM ROUGHLY THE GOTHENBURG AREA NORTHEASTWARD TO ARCADIA/ORD/GREELEY EARLY THIS AFTERNOON. THE RAP HAS BEEN HANDLING THE ONGOING/SHORT TERM TIME FRAME WELL AND HAVE FOLLOWED CLOSE TO THIS THROUGH THE EVENING. THE MID LEVEL TROUGH WILL CONTINUE TO TRANSLATE EASTWARD ACROSS THE INTERIOR CONUS THROUGH THE REMAINDER OF THE AFTN/EARLY EVENING. ISENTROPIC LIFT AHEAD OF THE SYSTEM WILL SHIFT EASTWARD DURING THE NEXT SEVERAL HOURS WITH MAIN RAIN AREA SHIFTING OFF TO THE EAST ACROSS EASTERN KS AND NEB. THE MID LEVEL H7 CIRCULATION TENDS TO INTERMITTENTLY CLOSE AS IT LIFTS TO NORTHEAST NEBRASKA WITH THE MAIN SNOW BAND/PSEUDO DEFORMATION REMAINING TO THE WEST/NORTHWEST OF OUR CWA. THIS BEING SAID...A FRONTOGENETIC BAND OF PCPN IS STILL EXPECTED INTO THE EVENING AS THE COLD FRONT ADVANCES SOUTHEASTWARD. AS THE COLDER AIR WORKS SOUTH...THE LINGERING RAIN WILL MIX WITH AND/OR CHANGE TO SNOW WITH THE TRANSITION TO ALL SNOW EXPECTED TO AFFECT LOCATIONS WEST OF A LINE FROM GENOA TO HASTINGS TO FRANKLIN FOR A BRIEF TIME. THE GREATER SNOW ACCUMULATIONS WILL REMAIN ACROSS OUR NW/W CWA...WHERE CURRENTLY A WINTER WEATHER ADVISORY IS IN EFFECT UNTIL MIDNIGHT. SNOWFALL IN THE ADVISORY AREA IS EXPECTED TO RANGE FROM 1 TO 3 INCHES...MAINLY ON GRASSY SURFACES AND LOCALLY HIGHER AMOUNTS CANNOT BE RULED OUT IF A SNOW BAND SETS UP THIS EVENING. THE LAST SNOW REPORT RECEIVED FROM THE ORD AREA EARLY THIS AFTERNOON HAD A SNOW ACCUMULATION OF JUST OVER ONE INCH. OUTSIDE OF THE ADVISORY AREA...LITTLE IF ANY SNOW ACCUMULATION IS EXPECTED. THE SNOW WILL RAPIDLY WIND DOWN DURING THE EVENING BEHIND THE PASSING MID LEVEL TROUGH AXIS. HAVE ENDED PCPN BY 06Z...BUT OUR FAR NORTH MAY SEE A FEW FLURRIES FOR AN HOUR OR SO. DRY AND COOLER CONDITIONS ARE FORECAST FOR WEDNESDAY IN THE WAKE OF THIS SYSTEM. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 255 PM CST TUE NOV 5 2013 WEDNESDAY NIGHT THROUGH TUESDAY. MAIN CONCERN WILL BE TEMPERATURES THROUGH PERIOD AND IF THERE WILL BE ANY PRECIPITATION NEXT TUESDAY. NORTHWEST FLOW WILL START THE PERIOD WITH A GRADUAL TRANSITION TO ZONAL FLOW TOWARD THE WEEKEND. THERE ARE VERY FEW UPPER LEVEL WAVES EXPECTED TO MOVE THROUGH THE AREA. AT THE SURFACE THERE IS A HIGH PRESSURE SYSTEM FOR WEDNESDAY NIGHT INTO THURSDAY THAT WILL MOVE TO THE EAST THURSDAY NIGHT. EXPECT DRY CONDITIONS WITH COOL TEMPERATURES WEDNESDAY NIGHT AND THURSDAY. WHEN THE SURFACE HIGH MOVES OFF TO THE EAST THURSDAY NIGHT THERE IS A LITTLE WARM ADVECTION AND TEMPERATURES WILL BE A LITTLE WARMER FOR THURSDAY NIGHT. THE WARMER TEMPERATURES WILL CONTINUE INTO FRIDAY...BUT WILL BE TEMPERED BY BREEZY CONDITIONS. THE PRESSURE GRADIENT TIGHTENS ON FRIDAY AND WITH WINDS ALOFT OF OVER 40 KTS EXPECT AT LEAST BREEZY CONDITIONS. A COLD FRONT WILL MOVE THROUGH THE FORECAST AREA FRIDAY NIGHT AND BRING A LITTLE BIT COOLER TEMPERATURES TO THE AREA FOR SATURDAY AND SUNDAY. EARLY NEXT WEEK THERE ARE VARYING SOLUTIONS WITH REGARD TO WHAT IS EXPECTED. BOTH THE GFS AND THE ECMWF HAVE NEARLY ZONAL FLOW. WITH SOUTH WINDS THE GFS BRINGS ADDITIONAL MOISTURE INTO THE AREA AND WITH WARM ADVECTION THERE COULD BE SOME LIGHT RAIN ON TUESDAY. THE ECMWF ON THE OTHER HAND HAS EAST WINDS AND KEEPS THE MOISTURE TO THE SOUTH OF THE FORECAST AREA AND DRY CONDITIONS. HAVE WENT A LITTLE CLOSER TO THE GFS AT THIS TIME AND HAVE A LITTLE LIGHT RAIN MAINLY IN THE SOUTHEAST PART OF THE AREA. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING) ISSUED AT 551 PM CST TUE NOV 5 2013 IFR CONDITIONS FORECAST THROUGH TONIGHT...WITH VFR CONDITIONS EXPECTED BY 13Z WEDNESDAY. LOW CLOUDS...WITH A CEILING NEAR 800FT AGL...PERSIST ACROSS THE REGION AS OF 2330Z AND THESE CLOUDS ARE EXPECTED TO PERSIST THROUGH MUCH OF THE NIGHT. AS THE STORM SYSTEM...CURRENTLY IMPACTING THE AREA...MOVES OFF TO THE NORTHEAST AND AWAY FROM THE REGION...AND WITH INCREASED DIABATIC HEATING POST-SUNRISE ON WEDNESDAY...THE CEILING AT GRI SHOULD INCREASE IN HEIGHT AND ACTUALLY DIMINISH DURING THE DAY WEDNESDAY. IN ADDITION TO THE LOW CEILING...VISIBILITY RESTRICTION...TO AROUND 2SM...WILL ALSO BE POSSIBLE IN FOG AND/OR PERIODS OF DRIZZLE THROUGH SUNRISE WEDNESDAY. THE SURFACE WIND WILL REMAIN FROM THE NORTHWEST TONIGHT...BUT DECREASE IN INTENSITY AND ACTUALLY BECOME FAIRLY LIGHT AND VARIABLE BY SUNRISE WEDNESDAY. BY WEDNESDAY AFTERNOON...MORE OF A WEST/SOUTHWEST SURFACE WIND SHOULD INFILTRATE THE AREA...SUSTAINED AT AROUND 09KTS. && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$ UPDATE...BRYANT SHORT TERM...FAY LONG TERM...JCB AVIATION...BRYANT
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
745 PM CST TUE NOV 5 2013 .UPDATE... HAVE TWEAKED GRIDS/FORECAST TO DECREASE PRECIPITATION CHANCES A BIT QUICKER THAT PREVIOUS FORECAST BASED ON RADAR AND SHORT RANGE MODEL TRENDS. DEFORMATION ZONE LIGHT SNOW WILL LIKELY WORK BACK INTO NORTHEAST NEBRASKA THIS EVENING...BUT ADDITIONAL AMOUNTS SHOULD BE MINIMAL AS INTENSITY WANES WITH TIME. DERGAN && .PREV DISCUSSION... /ISSUED 534 PM CST TUE NOV 5 2013/ AVIATION...00Z TAFS FOR KOFK...KLNK AND KOMA. IFR CONDITIONS WILL CONTINUE AT ALL TAF SITES THROUGH ABOUT 14Z. LARGE AREA OF PRECIPITATION WILL GRADUALLY SHIFT EAST OF THE AREA BY 08Z...HOWEVER LOW CLOUDS BELOW FL010 WILL REMAIN. VSBYS WILL BE VARIABLE BETWEEN 2 AND 5SM...WITH DRIZZLE POSSIBLE BETWEEN MAIN RAIN/SNOW AREAS. THE RAIN/SNOW LINE WILL REMAIN NORTHWEST OF THE KOMA AND KLNK AREAS THROUGH THE NIGHT...BUT A MIX OF RAIN AND SNOW COULD OCCUR AT THOSE SITES AS THE PRECIPITATION WINDS DOWN. IFR CIGS SHOULD GRADUALLY LIFT TO MVFR AROUND 14Z...WITH VFR CONDITIONS EXPECTED SOMETIME AFTER 20Z. DERGAN PREV DISCUSSION... /ISSUED 303 PM CST TUE NOV 5 2013/ SHORT TERM...TONIGHT THROUGH FRIDAY. UPPER TROUGH TO OUR WEST CONTINUES TO WORK SLOWLY EAST PER AFTERNOON STLT IMAGERY. THIS SYSTEM HAS BEEN VERY EFFICIENT IN GENERATING PRECIP ACROSS THE FORECAST AREA TODAY...SOME LIQUID AMOUNTS HAVE PUSHED PAST 1 INCH...AS IT PRODUCED DECENT FRONTOGENETICAL FORCING WHICH TAPPED DECENT LOWER LEVEL MOISTURE. THIS IS/WAS DESPITE ANEMIC UPPER HGT FALLS...20-40M AT H5. SHORT TERM QPF FROM 4KM WRF/RAP AND HRRR CONTINUE TO LIFT PRECIP ENE WITH IT EXITING SWRN ZONES NOT TOO LONG AFTER THE 00Z-03Z TIME PERIOD WITH A DEFORMATION BAND OF DWINDLING PRECIP PROBABLY LINGERING OVER NERN NEBR ALL NIGHT AND POSSIBLY SOME TRACE FLURRIES YET IN THE MORNING. BASED ON CURRENT STLT/RADAR TRENDS THIS LOOKS REASONABLE. WILL LEAVE WINTER WEATHER HEADLINE ALONE FOR THIS EVENING ALTHOUGH ACCUMULATIONS THUS FAR ON SERN EDGE OF ADVISORY HAVE BEEN MOSTLY LIMITED TO GRASSY SURFACES AND GENERALLY LESS THAN FORECAST DUE TO WARM GROUND AND SFC TEMPS AT OR A LITTLE ABOVE FREEZING. WITH APPROACHING NIGHTFALL...SNOW ACCUMULATIONS SHOULD BE A LITTLE MORE EASILY TO COME BY BUT MOST ADDITIONAL SHOULD BE AN INCH OR TWO...OR LESS...AFT 00Z. THE RAIN/SNOW MIX MAY MAKE IT TO OMAHA/LINCOLN BUT IT APPEARS COLDER AIR SUPPORTING THE CHANGEOVER WILL BE ARRIVING ABOUT THE SAME TIME THE PRECIP ENDS AT THOSE CITIES. OTHERWISE...FORECAST IN THE SHORTER TERM IS MAINLY TEMPERATURE DRIVEN AND LITTLE CHANGES WERE MADE TO FORECAST HIGHS WED THROUGH FRIDAY. DID BUMP THEM UP A FEW DEGREES SOUTH ON WED WHERE GROUND WILL BE ABSENT ANY SNOW AS WIND DIRECTION...NW SHIFTING TO WSW WILL BE FAVORABLE FOR MIXING. BUT IF CLOUDS FAIL TO CLEAR...WHICH WAS NOT EXPECTED...HIGHS WOULD BE A BIT COOLER. ANY RESIDUAL SNOW COVER WILL HAVE A DWINDLING IMPACT ON HIGHS THURSDAY AND ESPECIALLY BY FRIDAY NORTH...WHICH WAS REFLECTED IN PREV FORECAST AND LOOKED GOOD BASED ON LATEST FORECAST SOUNDINGS. MAIN CHANGE BEYOND WEDNESDAY WAS TO LOWER LOWS A CATEGORY OR SO THURSDAY NIGHT .ESPECIALLY E...AS RETURN FLOW WILL PROBABLY SET UP TOO LATE TO KEEP MANY TEMPS FROM DROPPING TOWARD THE MID/UPPER 20S THAT GUIDANCE FORECAST. CHERMOK LONG TERM...FRIDAY NIGHT THROUGH TUESDAY. MEDIUM RANGE MODELS LEAVE LITTLE TO BE DESIRED IN THE EXTENDED PDS WITH GREAT VARIATION SEEN BTWN THE ECM/GFS/CMC. THUS MAKING TEMP FCST AS WELL AS POTENTIAL PCPN MON NIGHT/TUES EXTREMELY PROBLEMATIC AT BEST. AS OF NOW...LATEST ECM PROGS LARGE SCALE FLOW TRANSITIONING FROM ZONAL TO DEVELOPING TWO SIGNIFICANT SHORTWAVE TROFS...ONE OVER THE PAC NW AND THE OTHER OVER THE GREAT LAKES THUS FAVORING A COLD PATTERN ACROSS THE CNTRL CONUS. THE GFS ON THE OTHER BASICALLY MAINTAINS RELATIVELY ZONAL FLOW. MEANWHILE THE CMC DIGS AN UPPER TROF THRU THE GREAT BASIN WITH SW FLOW ALOFT PREVAILING. COMPARISON OF MAX/MIN TEMPS BTWN THE 05/00Z ECMMOS AND 05/12Z MEX CLEARLY SHOWING THE DISTINCTION. HIGHS PROGGED NEXT TUES AT KOMA...ECM MOS 36/MEX 49. GIVEN THAT THE ECM HAS PROVEN TO OUT PERFORM ON A REGULAR BASIS...FEEL COMPELLED TO TREND TOWARD THE COOLER SOLUTION. AS FOR POSSIBLE PCPN MON NIGHT/TUES...WILL AGAIN OPT TO GO WITH THE DRIER ECM. DEE && .OAX WATCHES/WARNINGS/ADVISORIES... NE...WINTER WEATHER ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR NEZ011- 012-016>018-030-031. IA...NONE. && $$ 99/99
AREA FORECAST DISCUSSION
NWS HASTINGS NE
551 PM CST TUE NOV 5 2013 .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 255 PM CST TUE NOV 5 2013 THE PRECIPITATION EVENT TODAY IS GENERALLY UNFOLDING AS EXPECTED WITH WIDESPREAD RAINFALL DURING THE MORNING...AND A CHANGE TO SNOW IN OUR W/NW BY MID/LATE MORNING. SEVERAL LOCATIONS PICKED UP AT LEAST ONE HALF OF AN INCH WHILE OTHER REPORTS OF OVER ONE INCH HAVE BEEN RECEIVED. THE RAIN HAS MIXED WITH AND MADE THE SWITCH TO SNOW FROM ROUGHLY THE GOTHENBURG AREA NORTHEASTWARD TO ARCADIA/ORD/GREELEY EARLY THIS AFTERNOON. THE RAP HAS BEEN HANDLING THE ONGOING/SHORT TERM TIME FRAME WELL AND HAVE FOLLOWED CLOSE TO THIS THROUGH THE EVENING. THE MID LEVEL TROUGH WILL CONTINUE TO TRANSLATE EASTWARD ACROSS THE INTERIOR CONUS THROUGH THE REMAINDER OF THE AFTN/EARLY EVENING. ISENTROPIC LIFT AHEAD OF THE SYSTEM WILL SHIFT EASTWARD DURING THE NEXT SEVERAL HOURS WITH MAIN RAIN AREA SHIFTING OFF TO THE EAST ACROSS EASTERN KS AND NEB. THE MID LEVEL H7 CIRCULATION TENDS TO INTERMITTENTLY CLOSE AS IT LIFTS TO NORTHEAST NEBRASKA WITH THE MAIN SNOW BAND/PSEUDO DEFORMATION REMAINING TO THE WEST/NORTHWEST OF OUR CWA. THIS BEING SAID...A FRONTOGENETIC BAND OF PCPN IS STILL EXPECTED INTO THE EVENING AS THE COLD FRONT ADVANCES SOUTHEASTWARD. AS THE COLDER AIR WORKS SOUTH...THE LINGERING RAIN WILL MIX WITH AND/OR CHANGE TO SNOW WITH THE TRANSITION TO ALL SNOW EXPECTED TO AFFECT LOCATIONS WEST OF A LINE FROM GENOA TO HASTINGS TO FRANKLIN FOR A BRIEF TIME. THE GREATER SNOW ACCUMULATIONS WILL REMAIN ACROSS OUR NW/W CWA...WHERE CURRENTLY A WINTER WEATHER ADVISORY IS IN EFFECT UNTIL MIDNIGHT. SNOWFALL IN THE ADVISORY AREA IS EXPECTED TO RANGE FROM 1 TO 3 INCHES...MAINLY ON GRASSY SURFACES AND LOCALLY HIGHER AMOUNTS CANNOT BE RULED OUT IF A SNOW BAND SETS UP THIS EVENING. THE LAST SNOW REPORT RECEIVED FROM THE ORD AREA EARLY THIS AFTERNOON HAD A SNOW ACCUMULATION OF JUST OVER ONE INCH. OUTSIDE OF THE ADVISORY AREA...LITTLE IF ANY SNOW ACCUMULATION IS EXPECTED. THE SNOW WILL RAPIDLY WIND DOWN DURING THE EVENING BEHIND THE PASSING MID LEVEL TROUGH AXIS. HAVE ENDED PCPN BY 06Z...BUT OUR FAR NORTH MAY SEE A FEW FLURRIES FOR AN HOUR OR SO. DRY AND COOLER CONDITIONS ARE FORECAST FOR WEDNESDAY IN THE WAKE OF THIS SYSTEM. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 255 PM CST TUE NOV 5 2013 WEDNESDAY NIGHT THROUGH TUESDAY. MAIN CONCERN WILL BE TEMPERATURES THROUGH PERIOD AND IF THERE WILL BE ANY PRECIPITATION NEXT TUESDAY. NORTHWEST FLOW WILL START THE PERIOD WITH A GRADUAL TRANSITION TO ZONAL FLOW TOWARD THE WEEKEND. THERE ARE VERY FEW UPPER LEVEL WAVES EXPECTED TO MOVE THROUGH THE AREA. AT THE SURFACE THERE IS A HIGH PRESSURE SYSTEM FOR WEDNESDAY NIGHT INTO THURSDAY THAT WILL MOVE TO THE EAST THURSDAY NIGHT. EXPECT DRY CONDITIONS WITH COOL TEMPERATURES WEDNESDAY NIGHT AND THURSDAY. WHEN THE SURFACE HIGH MOVES OFF TO THE EAST THURSDAY NIGHT THERE IS A LITTLE WARM ADVECTION AND TEMPERATURES WILL BE A LITTLE WARMER FOR THURSDAY NIGHT. THE WARMER TEMPERATURES WILL CONTINUE INTO FRIDAY...BUT WILL BE TEMPERED BY BREEZY CONDITIONS. THE PRESSURE GRADIENT TIGHTENS ON FRIDAY AND WITH WINDS ALOFT OF OVER 40 KTS EXPECT AT LEAST BREEZY CONDITIONS. A COLD FRONT WILL MOVE THROUGH THE FORECAST AREA FRIDAY NIGHT AND BRING A LITTLE BIT COOLER TEMPERATURES TO THE AREA FOR SATURDAY AND SUNDAY. EARLY NEXT WEEK THERE ARE VARYING SOLUTIONS WITH REGARD TO WHAT IS EXPECTED. BOTH THE GFS AND THE ECMWF HAVE NEARLY ZONAL FLOW. WITH SOUTH WINDS THE GFS BRINGS ADDITIONAL MOISTURE INTO THE AREA AND WITH WARM ADVECTION THERE COULD BE SOME LIGHT RAIN ON TUESDAY. THE ECMWF ON THE OTHER HAND HAS EAST WINDS AND KEEPS THE MOISTURE TO THE SOUTH OF THE FORECAST AREA AND DRY CONDITIONS. HAVE WENT A LITTLE CLOSER TO THE GFS AT THIS TIME AND HAVE A LITTLE LIGHT RAIN MAINLY IN THE SOUTHEAST PART OF THE AREA. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING) ISSUED AT 551 PM CST TUE NOV 5 2013 IFR CONDITIONS FORECAST THROUGH TONIGHT...WITH VFR CONDITIONS EXPECTED BY 13Z WEDNESDAY. LOW CLOUDS...WITH A CEILING NEAR 800FT AGL...PERSIST ACROSS THE REGION AS OF 2330Z AND THESE CLOUDS ARE EXPECTED TO PERSIST THROUGH MUCH OF THE NIGHT. AS THE STORM SYSTEM...CURRENTLY IMPACTING THE AREA...MOVES OFF TO THE NORTHEAST AND AWAY FROM THE REGION...AND WITH INCREASED DIABATIC HEATING POST-SUNRISE ON WEDNESDAY...THE CEILING AT GRI SHOULD INCREASE IN HEIGHT AND ACTUALLY DIMINISH DURING THE DAY WEDNESDAY. IN ADDITION TO THE LOW CEILING...VISIBILITY RESTRICTION...TO AROUND 2SM...WILL ALSO BE POSSIBLE IN FOG AND/OR PERIODS OF DRIZZLE THROUGH SUNRISE WEDNESDAY. THE SURFACE WIND WILL REMAIN FROM THE NORTHWEST TONIGHT...BUT DECREASE IN INTENSITY AND ACTUALLY BECOME FAIRLY LIGHT AND VARIABLE BY SUNRISE WEDNESDAY. BY WEDNESDAY AFTERNOON...MORE OF A WEST/SOUTHWEST SURFACE WIND SHOULD INFILTRATE THE AREA...SUSTAINED AT AROUND 09KTS. && .GID WATCHES/WARNINGS/ADVISORIES... NE...WINTER WEATHER ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR NEZ039- 040-046-060. KS...NONE. && $$ SHORT TERM...FAY LONG TERM...JCB AVIATION...BRYANT
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
534 PM CST TUE NOV 5 2013 .AVIATION...00Z TAFS FOR KOFK...KLNK AND KOMA. IFR CONDITIONS WILL CONTINUE AT ALL TAF SITES THROUGH ABOUT 14Z. LARGE AREA OF PRECIPITATION WILL GRADUALLY SHIFT EAST OF THE AREA BY 08Z...HOWEVER LOW CLOUDS BELOW FL010 WILL REMAIN. VSBYS WILL BE VARIABLE BETWEEN 2 AND 5SM...WITH DRIZZLE POSSIBLE BETWEEN MAIN RAIN/SNOW AREAS. THE RAIN/SNOW LINE WILL REMAIN NORTHWEST OF THE KOMA AND KLNK AREAS THROUGH THE NIGHT...BUT A MIX OF RAIN AND SNOW COULD OCCUR AT THOSE SITES AS THE PRECIPITATION WINDS DOWN. IFR CIGS SHOULD GRADUALLY LIFT TO MVFR AROUND 14Z...WITH VFR CONDITIONS EXPECTED SOMETIME AFTER 20Z. DERGAN && .PREV DISCUSSION... /ISSUED 303 PM CST TUE NOV 5 2013/ SHORT TERM...TONIGHT THROUGH FRIDAY. UPPER TROUGH TO OUR WEST CONTINUES TO WORK SLOWLY EAST PER AFTERNOON STLT IMAGERY. THIS SYSTEM HAS BEEN VERY EFFICIENT IN GENERATING PRECIP ACROSS THE FORECAST AREA TODAY...SOME LIQUID AMOUNTS HAVE PUSHED PAST 1 INCH...AS IT PRODUCED DECENT FRONTOGENETICAL FORCING WHICH TAPPED DECENT LOWER LEVEL MOISTURE. THIS IS/WAS DESPITE ANEMIC UPPER HGT FALLS...20-40M AT H5. SHORT TERM QPF FROM 4KM WRF/RAP AND HRRR CONTINUE TO LIFT PRECIP ENE WITH IT EXITING SWRN ZONES NOT TOO LONG AFTER THE 00Z-03Z TIME PERIOD WITH A DEFORMATION BAND OF DWINDLING PRECIP PROBABLY LINGERING OVER NERN NEBR ALL NIGHT AND POSSIBLY SOME TRACE FLURRIES YET IN THE MORNING. BASED ON CURRENT STLT/RADAR TRENDS THIS LOOKS REASONABLE. WILL LEAVE WINTER WEATHER HEADLINE ALONE FOR THIS EVENING ALTHOUGH ACCUMULATIONS THUS FAR ON SERN EDGE OF ADVISORY HAVE BEEN MOSTLY LIMITED TO GRASSY SURFACES AND GENERALLY LESS THAN FORECAST DUE TO WARM GROUND AND SFC TEMPS AT OR A LITTLE ABOVE FREEZING. WITH APPROACHING NIGHTFALL...SNOW ACCUMULATIONS SHOULD BE A LITTLE MORE EASILY TO COME BY BUT MOST ADDITIONAL SHOULD BE AN INCH OR TWO...OR LESS...AFT 00Z. THE RAIN/SNOW MIX MAY MAKE IT TO OMAHA/LINCOLN BUT IT APPEARS COLDER AIR SUPPORTING THE CHANGEOVER WILL BE ARRIVING ABOUT THE SAME TIME THE PRECIP ENDS AT THOSE CITIES. OTHERWISE...FORECAST IN THE SHORTER TERM IS MAINLY TEMPERATURE DRIVEN AND LITTLE CHANGES WERE MADE TO FORECAST HIGHS WED THROUGH FRIDAY. DID BUMP THEM UP A FEW DEGREES SOUTH ON WED WHERE GROUND WILL BE ABSENT ANY SNOW AS WIND DIRECTION...NW SHIFTING TO WSW WILL BE FAVORABLE FOR MIXING. BUT IF CLOUDS FAIL TO CLEAR...WHICH WAS NOT EXPECTED...HIGHS WOULD BE A BIT COOLER. ANY RESIDUAL SNOW COVER WILL HAVE A DWINDLING IMPACT ON HIGHS THURSDAY AND ESPECIALLY BY FRIDAY NORTH...WHICH WAS REFLECTED IN PREV FORECAST AND LOOKED GOOD BASED ON LATEST FORECAST SOUNDINGS. MAIN CHANGE BEYOND WEDNESDAY WAS TO LOWER LOWS A CATEGORY OR SO THURSDAY NIGHT ..ESPECIALLY E...AS RETURN FLOW WILL PROBABLY SET UP TOO LATE TO KEEP MANY TEMPS FROM DROPPING TOWARD THE MID/UPPER 20S THAT GUIDANCE FORECAST. CHERMOK LONG TERM...FRIDAY NIGHT THROUGH TUESDAY. MEDIUM RANGE MODELS LEAVE LITTLE TO BE DESIRED IN THE EXTENDED PDS WITH GREAT VARIATION SEEN BTWN THE ECM/GFS/CMC. THUS MAKING TEMP FCST AS WELL AS POTENTIAL PCPN MON NIGHT/TUES EXTREMELY PROBLEMATIC AT BEST. AS OF NOW...LATEST ECM PROGS LARGE SCALE FLOW TRANSITIONING FROM ZONAL TO DEVELOPING TWO SIGNIFICANT SHORTWAVE TROFS...ONE OVER THE PAC NW AND THE OTHER OVER THE GREAT LAKES THUS FAVORING A COLD PATTERN ACROSS THE CNTRL CONUS. THE GFS ON THE OTHER BASICALLY MAINTAINS RELATIVELY ZONAL FLOW. MEANWHILE THE CMC DIGS AN UPPER TROF THRU THE GREAT BASIN WITH SW FLOW ALOFT PREVAILING. COMPARISON OF MAX/MIN TEMPS BTWN THE 05/00Z ECMMOS AND 05/12Z MEX CLEARLY SHOWING THE DISTINCTION. HIGHS PROGGED NEXT TUES AT KOMA...ECM MOS 36/MEX 49. GIVEN THAT THE ECM HAS PROVEN TO OUT PERFORM ON A REGULAR BASIS...FEEL COMPELLED TO TREND TOWARD THE COOLER SOLUTION. AS FOR POSSIBLE PCPN MON NIGHT/TUES...WILL AGAIN OPT TO GO WITH THE DRIER ECM. DEE && .OAX WATCHES/WARNINGS/ADVISORIES... NE...WINTER WEATHER ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR NEZ011- 012-016>018-030-031. IA...NONE. && $$
AREA FORECAST DISCUSSION...UPDATED
NWS ALBUQUERQUE NM
506 PM MST TUE NOV 5 2013 .AVIATION... 00Z TAF CYCLE BACK DOOR FRONT IS QUICKLY SLIDING DOWN THE EASTERN PLAINS THIS EVENING. NORTH WINDS OF 15 TO 25 WITH GUSTS NEAR 35 KTS ARE LIKELY BEHIND THE FRONT. A FEW SHOWERS...MAINLY SNOW...WILL BE POSSIBLE ACROSS NE NM WILL THROUGH APPROX 03Z. ELSEWHERE...A FEW NW WIND GUSTS NEAR 25KTS WILL REMAIN POSSIBLE THROUGH 01-02Z. BRIEF MVFR CIGS ARE POSSIBLE IN THE SHOWERS ACROSS THE NE...OTHERWISE... CLOUDS SHOULD SLOWLY CLEAR OUT THROUGH THE OVERNIGHT HOURS BEHIND THE UPPER LEVEL TROUGH AXIS. VFR CONDITIONS ARE EXPECTED ON WEDNESDAY. 34 && .PREV DISCUSSION...247 PM MST TUE NOV 5 2013... IMPRESSIVE WEATHER SYSTEM THAT HAS IMPACTED THE REGION OVER ROUGHLY THE PAST 18 HOURS IS BEGINNING TO MOVE OUT OF THE AREA. INSTABILITY SHOWERS CONTINUE OVER CENTRAL AND WESTERN NM HOWEVER THESE WILL QUICKLY DIMINISH AROUND SUNSET AS A POTENT DRY SLOT SHIFTS EAST INTO THE AREA. A BACK DOOR FRONTAL BOUNDARY HAS SHIFTED INTO THE NORTHEAST AND TEMPS ARE PLUMMETING ON GUSTY NORTH WINDS. LATEST HRRR AND RUC GUIDANCE WITH SUPPORT FROM SREF INDICATES THE POTENTIAL OR A SMALL BAND OF SNOW ALONG THE EAST SLOPES OF THE SANGRES BETWEEN RED RIVER AND RATON PASS...AND FROM NEAR DES MOINES/CAPULIN EAST TO CLAYTON FOR A FEW HOURS THIS EVENING. HAVE FOCUSED CHANCE POPS IN THIS AREA. THE MAIN FOCUS WILL SHIFT TO VERY COLD TEMPS TONIGHT AS A STRONG 1035MB HIGH PRESSURE CENTER BUILDS OVER COLORADO AND EXCEPTIONALLY DRY AIR INVADES THE STATE. 20Z OBS ACROSS THE NW CORNER AND AROUND SW COLORADO ALREADY HAVE FALLEN INTO THE LOWER TEENS. CLEAR SKIES ON TAP WILL LEAD TO IMPRESSIVE RADIATIONAL COOLING. HIGH WEDNESDAY WILL REMAIN NEAR 5 TO 10F WITH LIGHTER WINDS AND MORE SUN MAKING IT FEEL A LITTLE WARMER THAN TODAY. WEDNESDAY NIGHT WILL SEE EVEN STRONGER TEMPERATURE INVERSIONS ACROSS THE AREA. WOULD NOT BE SURPRISED TO SEE THE RANGE OF MIN TEMPS WITHIN THE ABQ METRO ON THE ORDER OF 20+ DEGREES BETWEEN THE VALLEY AND FOOTHILLS. A FAST MOVING DRY UPPER LEVEL TROUGH WILL SWING ACROSS COLORADO AND INCREASE WESTERLY WINDS OVER EASTERN NM. DOWNSLOPING WILL LEAD TO MODIFYING TEMPS WITH READINGS NOW 5 TO 10F ABOVE NORMAL. NEUTRAL TO VERY WEAK COLD ADVECTION BEHIND THIS WAVE WILL BE QUICKLY REPLACED BY WARM ADVECTION AS THE FLOWS SHIFTS MORE TO THE SOUTHWEST. THE WEEKEND AND EARLY NEXT WEEK LOOK VERY NICE AS TEMPS MODIFYING ABOVE NORMAL FOR THE ENTIRE AREA. GUYER .FIRE WEATHER... A FEW SNOW SHOWERS WILL BE POSSIBLE FROM THE SANGRE DE CRISTO MOUNTAINS EASTWARD THIS EVENING AS AN UPPER LEVEL TROUGH EXITS THE AREA TO THE EAST. ONLY LIGHT ADDITIONAL ACCUMULATION IS EXPECTED. IN ADDITION...A GUSTY BACK DOOR COLD FRONT WILL DROP SOUTHWARD THROUGH THE EASTERN PLAINS TONIGHT. WITH A LOW AMPLITUDE RIDGE OF HIGH PRESSURE ALOFT MOVING IN FROM THE WEST...HIGH TEMPERATURES ALONG AND WEST OF I-25 ARE EXPECTED TO WARM A FEW TO 11 DEGREES ON WEDNESDAY COMPARED TO TODAYS READINGS. FARTHER EAST...READINGS SHOULD FALL A FEW TO 11 DEGREES DUE TO THE BACK DOOR COLD FRONT. WIDESPREAD POOR VENTILATION IS ALSO EXPECTED WEDNESDAY...EXCEPT FOR THE EAST SLOPES OF THE CENTRAL MOUNTAIN CHAIN AND THE NORTHEAST PLAINS WHERE BETTER VENTILATION IS EXPECTED DUE TO A WEAK LEE TROUGH. VENTILATION SHOULD IMPROVE IN MOST LOCATIONS THURSDAY AS TEMPERATURES RISE A FEW TO 9 DEGREES...EXCEPT FROM ALBUQUERQUE TO GALLUP...FARMINGTON AND CHAMA WHERE A BROAD AREA OF POOR VENTILATION SHOULD PERSIST AS THE LOW AMPLITUDE RIDGE OF HIGH PRESSURE CROSSES ALOFT. ANOTHER UPPER LEVEL TROUGH WILL PASS NORTH OF NEW MEXICO FRIDAY CAUSING WESTERLY MOUNTAIN TOP WINDS TO STRENGTHEN TO 20-35 KTS WHILE A SHARP LEE TROUGH DEVELOPS AT THE SURFACE. SURFACE WINDS SHOULD BECOME GUSTY WITH DECENT VENTILATION AREAWIDE. SURFACE WINDS SHOULD BE BREEZIEST IN THE SANGRE DE CRISTO MOUNTAINS AND ACROSS PARTS OF THE EAST CENTRAL AND NORTHEAST PLAINS. IN THE WAKE OF THIS UPPER LEVEL TROUGH...TEMPERATURES SHOULD FALL A FEW TO 9 DEGREES ACROSS THE EAST ON SATURDAY AS A WEAK BACK DOOR COLD FRONT SAGS SOUTHWARD THROUGH THE PLAINS. POOR VENTILATION MAY ALSO BECOME WIDESPREAD AGAIN ON SATURDAY AS WINDS WEAKEN ALOFT AND AT THE SURFACE. POOR VENTILATION IS EXPECTED TO LINGER ACROSS NORTHERN...CENTRAL AND WESTERN AREAS ON SUNDAY AS THE FLOW ALOFT BEGINS TO TURN A BIT OUT OF THE SOUTHWEST IN RESPONSE TO A DEEPENING LOW PRESSURE SYSTEM OFF THE PACIFIC NW COAST. TEMPERATURES SHOULD ALSO REBOUND ABOVE NORMAL AGAIN AFTER SATURDAYS BRIEF COOL DOWN ON THE PLAINS. 44 && .ABQ WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION...UPDATED
NWS ABERDEEN SD
1119 AM CST MON NOV 4 2013 .UPDATE... 18Z AVIATION DISCUSSION INCLUDED BELOW... ADJUSTED POPS THIS MORNING AS THE LIGHT SHOWERS ARE QUICKLY PUSHING EAST...AND HAVE ALMOST EXITED THE CWA. ALSO BUMPED UP SKY COVER BASED ON LATEST SATELLITE IMAGES. TEMPERATURES AND WINDS ARE WELL PORTRAYED AT THIS TIME. && .PREVIOUS DISCUSSION... .SHORT TERM...TODAY THROUGH WEDNESDAY A SURFACE COLD FRONT HAS PUSHED ACROSS THE REGION THIS MORNING WITH ONLY A SHIFT IN WIND DIRECTION NOTED. HOWEVER AN UPPER LEVEL JET STREAK...ALONG WITH A H85 BAROCLINIC ZONE IS PRODUCING A NARROW BAND OF LIGHT PRECIPITATION OVER WESTERN NE...EXTREME SOUTH CENTRAL SD. THE PAST FEW RUNS OF THE RUC BRINGS THIS BAND OF PCPN NORTHEASTWARD THROUGH THE EARLY AFTERNOON HOURS BEFORE EXITING THE CWA BY 20Z. BASED ON THERMAL PROFILES...MOST OF THE PCPN SHOULD FALL AS LIGHT RAIN....WITH THE EXCEPTION TO THE MORNING HOURS. AN AREA OF HIGH PRESSURE BUILDING INTO THE REGION TONIGHT WILL BRING DRY AND COLD CONDITIONS THROUGH TUESDAY MORNING. THE PAST FEW MODEL RUNS OF THE GFS AND THE NAM HAVE SHOWN LOW TEMPERATURES TONIGHT COULD BE SIGNIFICANTLY LOWER THAN CURRENTLY FORECAST. BOTH MODELS SHOW THE JAMES RIVER VALLEY FALLING TO THE MID TEENS. THIS SEEMS A LITTLE UNLIKELY BASED ON CURRENT TEMPERATURES IN THE 20S UPSTREAM. THIS HIGH PRESSURE WILL BRING SIGNIFICANTLY DRIER AIR INTO THE REGION WITH BOUNDARY LAYER DEW POINT DEPRESSIONS AOA 20C OVER MOST OF THE CWA FROM TUESDAY/TUESDAY NIGHT. A STORM SYSTEM PASSING ACROSS THE CENTRAL PLAINS ON TUESDAY/TUESDAY NIGHT WILL TRY AND ERODE THE VERY DRY AIR. HOWEVER WITH LIMITED LIFT IN THE SNOW GROWTH REGION...BELIEVE THIS STORM SYSTEM WILL ONLY AFFECT LOCATIONS SOUTH OF HIGHWAY 212...WITH THE I-90 CORRIDOR LIKELY SEEING THE HIGHEST SNOWFALL AMOUNTS OF 1 TO 3 INCHES. .LONG TERM...WEDNESDAY NIGHT THROUGH SUNDAY THE BACK SIDE OF AN UPPER LEVEL TROUGH WILL PUSH ACROSS THE REGION WEDNESDAY NIGHT...WITH WEAK RIDGING SETTING UP THURSDAY AND THURSDAY NIGHT. ANOTHER TROUGH WILL TRACK ACROSS THE NORTHERN AND CENTRAL PLAINS FRIDAY...THEN NEARLY ZONAL FLOW WILL BE DOMINANT THROUGH THE REMAINDER OF THE PERIOD. AT THE SURFACE...BROAD LOW PRESSURE OVER THE PLAINS WEDNESDAY EVENING WILL GET PUSHED EASTWARD WEDNESDAY NIGHT BY A LARGE HIGH PRESSURE SYSTEM APPROACHING FROM THE WEST. THIS HIGH REMAINS OVER THE REGION UNTIL THURSDAY NIGHT WHEN ANOTHER LOW PRESSURE APPROACHES. AS THE LOW TRACKS ACROSS THE PLAINS...THE MODELS ARE IN GOOD AGREEMENT WITH PRECIPITATION DEVELOPING WITH IT...JUST NOT IS EXACTLY WHERE. FOR NOW...WILL STICK WILL SCHC/CHC POPS FRIDAY AND FRIDAY NIGHT. HIGH PRESSURE MOVES BACK IN AND LOOKS TO KEEP THINGS DRY OVER THE WEEKEND. TEMPERATURES WILL BE RIGHT AROUND NORMAL WITH HIGHS MAINLY IN THE 40S...AND OVERNIGHT LOWS IN THE 20S. && .AVIATION... 18Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS VFR CONDITIONS ARE EXPECTED THROUGH THE TAF PERIOD. WILL SEE INCREASING CLOUDS OVERNIGHT AND INTO EARLY TUESDAY FOR KPIR/KATY AS A SYSTEM MOVES MAINLY SOUTH OF THE FORECAST AREA...WITH THE POSSIBILITY FOR SOME OF THE LIGHT SNOW TO MAKE IT INTO KPIR TERMINAL LATE IN THE TAF PERIOD. WINDS WILL BE OUT OF THE WEST/NORTHWEST TODAY AND GUSTY...BUT WILL SUBSIDE AND SHIFT TO MORE NORTHERLY OVERNIGHT. && .ABR WATCHES/WARNINGS/ADVISORIES... SD...NONE. MN...NONE. && $$ UPDATE...WISE SHORT TERM...SD LONG TERM...PARKIN AVIATION...CONNELLY WEATHER.GOV/ABERDEEN
AREA FORECAST DISCUSSION...UPDATED
NWS ABERDEEN SD
1016 AM CST MON NOV 4 2013 .UPDATE... ADJUSTED POPS THIS MORNING AS THE LIGHT SHOWERS ARE QUICKLY PUSHING EAST...AND HAVE ALMOST EXITED THE CWA. ALSO BUMPED UP SKY COVER BASED ON LATEST SATELLITE IMAGES. TEMPERATURES AND WINDS ARE WELL PORTRAYED AT THIS TIME. && .PREVIOUS DISCUSSION... .SHORT TERM...TODAY THROUGH WEDNESDAY A SURFACE COLD FRONT HAS PUSHED ACROSS THE REGION THIS MORNING WITH ONLY A SHIFT IN WIND DIRECTION NOTED. HOWEVER AN UPPER LEVEL JET STREAK...ALONG WITH A H85 BAROCLINIC ZONE IS PRODUCING A NARROW BAND OF LIGHT PRECIPITATION OVER WESTERN NE...EXTREME SOUTH CENTRAL SD. THE PAST FEW RUNS OF THE RUC BRINGS THIS BAND OF PCPN NORTHEASTWARD THROUGH THE EARLY AFTERNOON HOURS BEFORE EXITING THE CWA BY 20Z. BASED ON THERMAL PROFILES...MOST OF THE PCPN SHOULD FALL AS LIGHT RAIN....WITH THE EXCEPTION TO THE MORNING HOURS. AN AREA OF HIGH PRESSURE BUILDING INTO THE REGION TONIGHT WILL BRING DRY AND COLD CONDITIONS THROUGH TUESDAY MORNING. THE PAST FEW MODEL RUNS OF THE GFS AND THE NAM HAVE SHOWN LOW TEMPERATURES TONIGHT COULD BE SIGNIFICANTLY LOWER THAN CURRENTLY FORECAST. BOTH MODELS SHOW THE JAMES RIVER VALLEY FALLING TO THE MID TEENS. THIS SEEMS A LITTLE UNLIKELY BASED ON CURRENT TEMPERATURES IN THE 20S UPSTREAM. THIS HIGH PRESSURE WILL BRING SIGNIFICANTLY DRIER AIR INTO THE REGION WITH BOUNDARY LAYER DEW POINT DEPRESSIONS AOA 20C OVER MOST OF THE CWA FROM TUESDAY/TUESDAY NIGHT. A STORM SYSTEM PASSING ACROSS THE CENTRAL PLAINS ON TUESDAY/TUESDAY NIGHT WILL TRY AND ERODE THE VERY DRY AIR. HOWEVER WITH LIMITED LIFT IN THE SNOW GROWTH REGION...BELIEVE THIS STORM SYSTEM WILL ONLY AFFECT LOCATIONS SOUTH OF HIGHWAY 212...WITH THE I-90 CORRIDOR LIKELY SEEING THE HIGHEST SNOWFALL AMOUNTS OF 1 TO 3 INCHES. .LONG TERM...WEDNESDAY NIGHT THROUGH SUNDAY THE BACK SIDE OF AN UPPER LEVEL TROUGH WILL PUSH ACROSS THE REGION WEDNESDAY NIGHT...WITH WEAK RIDGING SETTING UP THURSDAY AND THURSDAY NIGHT. ANOTHER TROUGH WILL TRACK ACROSS THE NORTHERN AND CENTRAL PLAINS FRIDAY...THEN NEARLY ZONAL FLOW WILL BE DOMINANT THROUGH THE REMAINDER OF THE PERIOD. AT THE SURFACE...BROAD LOW PRESSURE OVER THE PLAINS WEDNESDAY EVENING WILL GET PUSHED EASTWARD WEDNESDAY NIGHT BY A LARGE HIGH PRESSURE SYSTEM APPROACHING FROM THE WEST. THIS HIGH REMAINS OVER THE REGION UNTIL THURSDAY NIGHT WHEN ANOTHER LOW PRESSURE APPROACHES. AS THE LOW TRACKS ACROSS THE PLAINS...THE MODELS ARE IN GOOD AGREEMENT WITH PRECIPITATION DEVELOPING WITH IT...JUST NOT IS EXACTLY WHERE. FOR NOW...WILL STICK WILL SCHC/CHC POPS FRIDAY AND FRIDAY NIGHT. HIGH PRESSURE MOVES BACK IN AND LOOKS TO KEEP THINGS DRY OVER THE WEEKEND. TEMPERATURES WILL BE RIGHT AROUND NORMAL WITH HIGHS MAINLY IN THE 40S...AND OVERNIGHT LOWS IN THE 20S. && .AVIATION... 12Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS VFR CONDITIONS WILL PREVAIL ACROSS THE AREA TODAY AND TONIGHT. A FEW LIGHT RAIN SHOWERS ARE POSSIBLE ACROSS PARTS OF THE SOUTHERN CWA THIS MORNING...BUT WILL NOT AMOUNT TO MUCH IN THE WAY OF AMOUNTS OR REDUCE CIGS OR VSBYS BELOW VFR LEVELS. NORTHWEST WINDS OF 15 TO 30 MPH WILL BE COMMON DURING THE LATE MORNING AND AFTERNOON HOURS. && .ABR WATCHES/WARNINGS/ADVISORIES... SD...NONE. MN...NONE. && $$ UPDATE...WISE SHORT TERM...SD LONG TERM...PARKIN AVIATION...PARKIN WEATHER.GOV/ABERDEEN
AREA FORECAST DISCUSSION...UPDATED
NWS ABERDEEN SD
525 AM CST MON NOV 4 2013 .UPDATE... SEE UPDATED AVIATION DISCUSSION BELOW. && .PREVIOUS DISCUSSION... .SHORT TERM...TODAY THROUGH WEDNESDAY A SURFACE COLD FRONT HAS PUSHED ACROSS THE REGION THIS MORNING WITH ONLY A SHIFT IN WIND DIRECTION NOTED. HOWEVER AN UPPER LEVEL JET STREAK...ALONG WITH A H85 BAROCLINIC ZONE IS PRODUCING A NARROW BAND OF LIGHT PRECIPITATION OVER WESTERN NE...EXTREME SOUTH CENTRAL SD. THE PAST FEW RUNS OF THE RUC BRINGS THIS BAND OF PCPN NORTHEASTWARD THROUGH THE EARLY AFTERNOON HOURS BEFORE EXITING THE CWA BY 20Z. BASED ON THERMAL PROFILES...MOST OF THE PCPN SHOULD FALL AS LIGHT RAIN....WITH THE EXCEPTION TO THE MORNING HOURS. AN AREA OF HIGH PRESSURE BUILDING INTO THE REGION TONIGHT WILL BRING DRY AND COLD CONDITIONS THROUGH TUESDAY MORNING. THE PAST FEW MODEL RUNS OF THE GFS AND THE NAM HAVE SHOWN LOW TEMPERATURES TONIGHT COULD BE SIGNIFICANTLY LOWER THAN CURRENTLY FORECAST. BOTH MODELS SHOW THE JAMES RIVER VALLEY FALLING TO THE MID TEENS. THIS SEEMS A LITTLE UNLIKELY BASED ON CURRENT TEMPERATURES IN THE 20S UPSTREAM. THIS HIGH PRESSURE WILL BRING SIGNIFICANTLY DRIER AIR INTO THE REGION WITH BOUNDARY LAYER DEW POINT DEPRESSIONS AOA 20C OVER MOST OF THE CWA FROM TUESDAY/TUESDAY NIGHT. A STORM SYSTEM PASSING ACROSS THE CENTRAL PLAINS ON TUESDAY/TUESDAY NIGHT WILL TRY AND ERODE THE VERY DRY AIR. HOWEVER WITH LIMITED LIFT IN THE SNOW GROWTH REGION...BELIEVE THIS STORM SYSTEM WILL ONLY AFFECT LOCATIONS SOUTH OF HIGHWAY 212...WITH THE I-90 CORRIDOR LIKELY SEEING THE HIGHEST SNOWFALL AMOUNTS OF 1 TO 3 INCHES. .LONG TERM...WEDNESDAY NIGHT THROUGH SUNDAY THE BACK SIDE OF AN UPPER LEVEL TROUGH WILL PUSH ACROSS THE REGION WEDNESDAY NIGHT...WITH WEAK RIDGING SETTING UP THURSDAY AND THURSDAY NIGHT. ANOTHER TROUGH WILL TRACK ACROSS THE NORTHERN AND CENTRAL PLAINS FRIDAY...THEN NEARLY ZONAL FLOW WILL BE DOMINANT THROUGH THE REMAINDER OF THE PERIOD. AT THE SURFACE...BROAD LOW PRESSURE OVER THE PLAINS WEDNESDAY EVENING WILL GET PUSHED EASTWARD WEDNESDAY NIGHT BY A LARGE HIGH PRESSURE SYSTEM APPROACHING FROM THE WEST. THIS HIGH REMAINS OVER THE REGION UNTIL THURSDAY NIGHT WHEN ANOTHER LOW PRESSURE APPROACHES. AS THE LOW TRACKS ACROSS THE PLAINS...THE MODELS ARE IN GOOD AGREEMENT WITH PRECIPITATION DEVELOPING WITH IT...JUST NOT IS EXACTLY WHERE. FOR NOW...WILL STICK WILL SCHC/CHC POPS FRIDAY AND FRIDAY NIGHT. HIGH PRESSURE MOVES BACK IN AND LOOKS TO KEEP THINGS DRY OVER THE WEEKEND. TEMPERATURES WILL BE RIGHT AROUND NORMAL WITH HIGHS MAINLY IN THE 40S...AND OVERNIGHT LOWS IN THE 20S. && .AVIATION... 12Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS VFR CONDITIONS WILL PREVAIL ACROSS THE AREA TODAY AND TONIGHT. A FEW LIGHT RAIN SHOWERS ARE POSSIBLE ACROSS PARTS OF THE SOUTHERN CWA THIS MORNING...BUT WILL NOT AMOUNT TO MUCH IN THE WAY OF AMOUNTS OR REDUCE CIGS OR VSBYS BELOW VFR LEVELS. NORTHWEST WINDS OF 15 TO 30 MPH WILL BE COMMON DURING THE LATE MORNING AND AFTERNOON HOURS. && .ABR WATCHES/WARNINGS/ADVISORIES... SD...NONE. MN...NONE. && $$ SHORT TERM...SD LONG TERM...PARKIN AVIATION...PARKIN WEATHER.GOV/ABERDEEN
AREA FORECAST DISCUSSION
NWS ABERDEEN SD
336 AM CST MON NOV 4 2013 .SHORT TERM...TODAY THROUGH WEDNESDAY A SURFACE COLD FRONT HAS PUSHED ACROSS THE REGION THIS MORNING WITH ONLY A SHIFT IN WIND DIRECTION NOTED. HOWEVER AN UPPER LEVEL JET STREAK...ALONG WITH A H85 BAROCLINIC ZONE IS PRODUCING A NARROW BAND OF LIGHT PRECIPITATION OVER WESTERN NE...EXTREME SOUTH CENTRAL SD. THE PAST FEW RUNS OF THE RUC BRINGS THIS BAND OF PCPN NORTHEASTWARD THROUGH THE EARLY AFTERNOON HOURS BEFORE EXITING THE CWA BY 20Z. BASED ON THERMAL PROFILES...MOST OF THE PCPN SHOULD FALL AS LIGHT RAIN....WITH THE EXCEPTION TO THE MORNING HOURS. AN AREA OF HIGH PRESSURE BUILDING INTO THE REGION TONIGHT WILL BRING DRY AND COLD CONDITIONS THROUGH TUESDAY MORNING. THE PAST FEW MODEL RUNS OF THE GFS AND THE NAM HAVE SHOWN LOW TEMPERATURES TONIGHT COULD BE SIGNIFICANTLY LOWER THAN CURRENTLY FORECAST. BOTH MODELS SHOW THE JAMES RIVER VALLEY FALLING TO THE MID TEENS. THIS SEEMS A LITTLE UNLIKELY BASED ON CURRENT TEMPERATURES IN THE 20S UPSTREAM. THIS HIGH PRESSURE WILL BRING SIGNIFICANTLY DRIER AIR INTO THE REGION WITH BOUNDARY LAYER DEW POINT DEPRESSIONS AOA 20C OVER MOST OF THE CWA FROM TUESDAY/TUESDAY NIGHT. A STORM SYSTEM PASSING ACROSS THE CENTRAL PLAINS ON TUESDAY/TUESDAY NIGHT WILL TRY AND ERODE THE VERY DRY AIR. HOWEVER WITH LIMITED LIFT IN THE SNOW GROWTH REGION...BELIEVE THIS STORM SYSTEM WILL ONLY AFFECT LOCATIONS SOUTH OF HIGHWAY 212...WITH THE I-90 CORRIDOR LIKELY SEEING THE HIGHEST SNOWFALL AMOUNTS OF 1 TO 3 INCHES. .LONG TERM...WEDNESDAY NIGHT THROUGH SUNDAY THE BACK SIDE OF AN UPPER LEVEL TROUGH WILL PUSH ACROSS THE REGION WEDNESDAY NIGHT...WITH WEAK RIDGING SETTING UP THURSDAY AND THURSDAY NIGHT. ANOTHER TROUGH WILL TRACK ACROSS THE NORTHERN AND CENTRAL PLAINS FRIDAY...THEN NEARLY ZONAL FLOW WILL BE DOMINANT THROUGH THE REMAINDER OF THE PERIOD. AT THE SURFACE...BROAD LOW PRESSURE OVER THE PLAINS WEDNESDAY EVENING WILL GET PUSHED EASTWARD WEDNESDAY NIGHT BY A LARGE HIGH PRESSURE SYSTEM APPROACHING FROM THE WEST. THIS HIGH REMAINS OVER THE REGION UNTIL THURSDAY NIGHT WHEN ANOTHER LOW PRESSURE APPROACHES. AS THE LOW TRACKS ACROSS THE PLAINS...THE MODELS ARE IN GOOD AGREEMENT WITH PRECIPITATION DEVELOPING WITH IT...JUST NOT IS EXACTLY WHERE. FOR NOW...WILL STICK WILL SCHC/CHC POPS FRIDAY AND FRIDAY NIGHT. HIGH PRESSURE MOVES BACK IN AND LOOKS TO KEEP THINGS DRY OVER THE WEEKEND. TEMPERATURES WILL BE RIGHT AROUND NORMAL WITH HIGHS MAINLY IN THE 40S...AND OVERNIGHT LOWS IN THE 20S. && .AVIATION... 06Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS VFR CONDITIONS WILL PREVAIL AT ALL FOUR TERMINALS THROUGH THE TAF PERIOD. A LOW PRESSURE SYSTEM IS BEGINNING TO WORK UP OVER THE REGION AND WITH IT A BAND OF PRECIPITATION. THERE IS ALREADY A BAND OF SNOW DEVELOPING ACROSS THE NEBRASKA PANHANDLE UP INTO SOUTHWEST SOUTH DAKOTA. THERE COULD BE A BRIEF PERIOD OF MVFR VISIBILITY IF A BAND OF RAIN SHOWERS CAN DEVELOP OVER-TOP OF THE KPIR OR KATY TERMINALS BETWEEN 06Z AND 18Z. FOR NOW...CONTINUING WITH A FEW HOURS OF LIGHT RAIN AT KPIR AND KATY. THE LOW PRESSURE SYSTEM AND ASSOCIATED PRECIPITATION SHOULD BE OUT OF THE REGION BY EARLY MONDAY AFTERNOON. && .ABR WATCHES/WARNINGS/ADVISORIES... SD...NONE. MN...NONE. && $$ SHORT TERM...SD LONG TERM...PARKIN AVIATION...PARKIN WEATHER.GOV/ABERDEEN
AREA FORECAST DISCUSSION
NWS AMARILLO TX
331 PM CST MON NOV 4 2013 .DISCUSSION... NOT MUCH CHANGE IN THE OVERALL STATE OF THE FORECAST WITH RAIN CHANCES RETURNING THIS EVENING. CURRENT WATER VAPOR IMAGERY SHOWS THAT THE PANHANDLES REMAIN LOCKED IN DRY SUBSIDENCE AIR BEHIND THE EARLY MORNING FRONT. THIS WILL BE A BIT OF A LIMITING FACTOR FOR PRECIP THIS EVENING AND OVERNIGHT. AS SUCH HAVE DELAYED POPS BY 3 HOURS THIS EVENING ACROSS THE WESTERN PANHANDLES WHILE LEAVING PERCENTAGES RELATIVELY UNCHANGED. AS THE UPPER LEVEL FORCING GETS CLOSER THIS DRY SLOT SHOULD LIFT NORTHEASTWARD ALLOWING SOME MOISTURE RETURN. INCREASED POPS IN THE NW AFTER MIDNIGHT TO REFLECT THE RECENT TREND OF HIGHER POPS FURTHER WEST AS SHOWN IN THE HRRR RUC. TUESDAY INTO WEDNESDAY...HAVE RETAINED PREVIOUS POPS AND STRUCTURE BUT SPED UP THE PASSAGE OF THE COLD FRONT BY ABOUT 6 HOURS. THIS FASTER FRONTAL PASSAGE IS A REFLECTION OF THE TREND THIS SEASON OF NOCTURNAL COLD FRONTS MOVING MUCH FURTHER SOUTH AS WELL AS MUCH SOONER THAN MODELS SUGGEST. THERE REMAINS A BRIEF WINDOW TUESDAY NIGHT WHERE THE NORTHWEST PANHANDLES MAY SEE SOME WINTRY MIX BUT LITTLE TO NO ACCUMULATION IS EXPECTED AT THIS TIME. WEDNESDAY INTO NEXT WEEK IS EXPECTED TO REMAIN DRY AND WILL SEE A SLOW WARMING TREND AFTER THE INITIAL DIP IN TEMPERATURES WEDNESDAY. THURSDAY MORNING REMAINS THE TIME FRAME FOR A THE NEXT WIDESPREAD KILLING FREEZE. && .FIRE WEATHER... NEITHER ELEVATED NOR CRITICAL FIRE WEATHER CONDITIONS ARE EXPECTED FOR THE NEXT SEVEN DAYS AS RELATIVE HUMIDITIES SHOULD REMAIN ABOVE 20 PERCENT OR 20 FOOT WINDS SHOULD REMAIN BELOW 15 MPH. && .AMA WATCHES/WARNINGS/ADVISORIES... TX...NONE. OK...NONE. && $$ 09/14
AREA FORECAST DISCUSSION...UPDATED
NWS FORT WORTH TX
1202 PM CST MON NOV 4 2013 .AVIATION... /18Z TAFS/ TRANSITIONING CIGS DOWN TO INTO MVFR/IFR BY THIS EVENING AND THROUGH EARLY WEDNESDAY TO BE A VERY CHALLENGING WITH OFF/ON MOSTLY -RA/-SHRA EXPECTED THROUGH TONIGHT. SHORTWAVE ENERGY WILL CONTINUE TO PERIODICALLY RIPPLE THROUGH THE STRONG SOUTHWEST FLOW ALOFT THROUGH TONIGHT. IN ADDITION... MOISTURE FROM THE REMNANTS OF TS SONIA YESTERDAY WILL ADD TO SUPPLY MOISTURE FOR THE OFF/ON -RA/-SHRA OVERNIGHT. MID LEVELS WILL REMAIN TOO WARM WITH MOIST-ADIABATIC LAPSE RATES. FEEL THE CHANCES FOR TS/VCTS WILL BE NEAR NIL THROUGH MIDDAY TUESDAY. VFR CIGS WITH SPOTTY IFR WILL START THE FORECAST...WITH MORE WIDESPREAD MVFR BY LATE AFTERNOON AS THE BOUNDARY LAYER CONTINUES TO SATURATE AND COOL. THE CONTINUOUS RAIN OVERNIGHT WILL LIKELY RESULT IN IFR CIGS AT ALL AIRPORTS FOR SEVERAL HOURS...THOUGH PERIODIC BREAKS INTO LOW MVFR MAY OCCUR FROM TIME TO TIME. VFR VSBYS WILL FALL INTO MVFR AS THE -RA/-SHRA BECOMES MORE WIDESPREAD TONIGHT. THE BEST WAA AND LIFT SHIFTS NORTHWARD OUT OF THE REGION AFTER SUNRISE AND WILL LIFT CIGS BACK UP INTO LOW MVFR CATEGORY... THOUGH IT IS CERTAINLY POSSIBLE IFR MAY MAINTAIN IF THE BOUNDARY CANNOT WARM AFTER SUNRISE OR IF THE RAIN LINGERS LONGER THAN EXPECTED. OTHERWISE...SOUTHEAST WINDS 10-14 KTS THIS AFTERNOON BACK TO THE EAST OR EAST-SOUTHEAST 7-9 KTS OVERNIGHT AND INTO EARLY TUESDAY. .OUTLOOK... CHANCES FOR VCTS/TS/TSRA TO INCREASE BY TUESDAY EVENING AND THROUGH MIDDAY WEDNESDAY...AS THE MAIN UPPER SYSTEM LIFTS OUT OVER THE PLAINS AND A COLD FRONT ARRIVES INTO THE AREA. FROPA ARRIVES INTO THE DFW METRO BETWEEN MIDNIGHT AND SUNRISE WEDNESDAY MORNING WITH WINDS SHIFTING NORTHWEST 15-20 KTS. FROPA AT WACO EXPECTED TO BE AROUND/OR SHORTLY AFTER SUNRISE WEDNESDAY. 05/ && .UPDATE... LARGE AREA OF LIGHT RAIN CONTINUES FOR LOCATIONS MAINLY SOUTH OF INTERSTATE 20. LATEST HRRR CONTINUES TO SHOW THIS AREA SLOWLY MOVING NORTH THROUGHOUT THE DAY TODAY AND WILL LEAVE THE LIKELY POPS IN THE FORECAST WHERE THEY CURRENTLY ARE. OVERNIGHT RAIN IS EXPECTED TO BE A BIT HEAVIER WITH DEEP ISENTROPIC LIFT ANTICIPATED. THE BEGINNING OF THAT LIFT IS ALREADY OCCURRING AND IS LEADING TO SHOWERS SOUTHWEST OF HOUSTON. HAMPSHIRE && .PREV DISCUSSION... /ISSUED 335 AM CST MON NOV 4 2013/ A WET START TO THE WORK WEEK IS EXPECTED ACROSS NORTH TEXAS AS ENERGY FROM AN APPROACHING LONG WAVE TROUGH INTERACTS WITH ABUNDANT MOISTURE. SCATTERED TO NUMEROUS SHOWERS ARE EXPECTED TODAY AND TONIGHT DUE TO INCREASING MOISTURE AND LARGE SCALE LIFT. HOWEVER...INSTABILITY SHOULD BE INSUFFICIENT FOR THUNDER. LARGE SCALE LIFT AND MOISTURE WILL INCREASE ON TUESDAY AND SHOWERS AND SOME THUNDERSTORMS ARE LIKELY. STRONG STORMS ARE NOT EXPECTED DUE TO LIMITED INSTABILITY. THE BEST FORCING AND MOISTURE WILL COME TOGETHER TUESDAY NIGHT AS THE UPPER TROUGH MOVES INTO WEST TEXAS AND A COLD FRONT APPROACHES FROM THE NORTHWEST. SHOWERS AND THUNDERSTORMS SHOULD ORGANIZE ALONG THE COLD FRONT AS IT MOVES THROUGH NORTH TEXAS EARLY WEDNESDAY MORNING. STORMS SHOULD END QUICKLY FROM NORTHWEST TO SOUTHEAST ON WEDNESDAY MORNING AS THE UPPER TROUGH AXIS MOVES EAST AND LARGE SCALE SUBSIDENCE INCREASES. OVERALL...THIS SHOULD BE A VERY BENEFICIAL RAIN EVENT FOR NORTH TEXAS WITH AVERAGE RAINFALL TOTALS BETWEEN ONE AND THREE INCHES OVER A 48 HOUR PERIOD. THE EXPECTED PRECIPITATION INTENSITY THROUGH THE EVENT SHOULD NOT RESULT IN FLASH FLOODING. HOWEVER...SOME OF THE RIVERS ACROSS THE SOUTHERN PORTIONS OF NORTH TEXAS THAT SAW FLOODING FROM THE LAST RAIN EVENT MAY RESPOND QUICKLY AND COULD GO BACK INTO FLOOD. A WEAK UPPER LEVEL RIDGE WILL BUILD FROM WEST TO EAST ACROSS THE COUNTRY THE SECOND HALF OF THE WEEK AND BRING DRY CONDITIONS TO THE REGION. THE UPPER FLOW WILL BECOME MORE ZONAL ON THE WEEKEND AND ALLOW A SURFACE TROUGH TO DEVELOP OVER THE SOUTHERN HIGH PLAINS. THIS PATTERN WILL RESULT IN AN INCREASE IN LOW LEVEL MOISTURE ACROSS NORTH TEXAS. HIGH TEMPERATURES THE FIRST HALF OF THE WEEK SHOULD BE BELOW SEASONAL NORMALS DUE TO ABUNDANT CLOUD COVER AND PRECIPITATION. HOWEVER...OVERNIGHT LOWS WILL BE IN THE 50S AND 60S DUE TO THE RETURN OF GULF MOISTURE. DRY AIR BEHIND THE COLD FRONT WEDNESDAY WILL RESULT IN VERY COOL TEMPERATURES THURSDAY MORNING WITH LOWS FROM THE UPPER 30S TO THE MIDDLE 40S AND SOME FROST POSSIBLE IN RURAL AREAS ACROSS THE NORTH AND WEST. A SLIGHT WARMING TREND IS EXPECTED ON THE WEEKEND DUE TO ABUNDANT SUN AND THE RETURN OF SOUTHERLY WINDS AND LOW LEVEL MOISTURE. 79 && .PRELIMINARY POINT TEMPS/POPS... DALLAS-FT. WORTH, TX 66 58 72 63 67 / 60 70 70 80 60 WACO, TX 66 62 74 64 67 / 60 60 50 80 60 PARIS, TX 63 54 68 62 66 / 60 70 70 80 70 DENTON, TX 66 58 72 62 65 / 60 70 70 80 40 MCKINNEY, TX 64 58 71 62 66 / 60 70 70 80 60 DALLAS, TX 65 59 72 63 66 / 60 70 70 80 60 TERRELL, TX 64 58 73 64 68 / 60 70 60 80 70 CORSICANA, TX 65 59 73 64 68 / 60 60 50 80 70 TEMPLE, TX 64 60 74 64 67 / 60 60 40 70 60 MINERAL WELLS, TX 67 57 72 57 64 / 60 70 70 70 40 && .FWD WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 05/85
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
542 PM CST TUE NOV 5 2013 .SHORT TERM...(TONIGHT AND WEDNESDAY) 320 PM CST TUE NOV 5 2013 ATTENTION SQUARELY ON THE SYSTEM MOVING THROUGH TONIGHT AND WEDNESDAY. WIDESPREAD RAIN TONIGHT...AND WITH COOLER AIR ON THE BACK SIDE OF THE SYSTEM...COULD SEE A MIX OR CHANGE TO SNOW... AND MAYBE EVEN FREEZING DRIZZLE. 20Z SURFACE ANALYSIS SHOWED THE LOW PRESSURE CENTER OVER KANSAS... WITH A WARM FRONT REACHING NORTHEAST INTO SOUTHERN WI. WATER VAPOR IMAGERY SHOWED A POTENT JET STREAK MOVING NORTHEAST ACROSS OK/KS. REGIONAL RADAR LOOPS SHOW AN EXPANSIVE AREA OF RAIN REACHING FROM IA AND NORTHERN IL UP INTO SOUTHEAST MN AND SOUTHERN WI. FROM NORTHERN NEBRASKA INTO SD... THE RADAR IMAGERY SHOWED A MORE LAMINAR LOOK...SUGGESTING SNOW. INDEED...LOOKING AT SURFACE OBSERVATIONS OUT THAT WAY...SNOW WAS INDEED FLYING. LATEST MODEL SIMULATIONS ARE IN PRETTY GOOD AGREEMENT WITH THE OVERALL EVOLUTION OF THIS SYSTEM AS IT PROGRESSES RATHER QUICKLY ACROSS THE REGION TONIGHT. THE LOW CENTER SHOULD BE OVER NW MO AROUND 00Z...AND IS EXPECTED TO BE IN EASTERN WI ALREADY BY 12Z. COPIOUS AMOUNTS OF MOISTURE AVAILABLE TO THE SYSTEM WITH PRECIPITABLE WATER OVER 200% OF NORMAL. PRECIPITATION IS A SLAM DUNK OBVIOUSLY...BUT THE MAIN CONCERN WITH THIS SYSTEM IS THE POSSIBILITY OF SNOW OR FREEZING DRIZZLE AS THE COLD AIR ARRIVES ON THE BACK SIDE OF THE SYSTEM. WITH THE TRACK OF THE STORM HEADING OVER SOUTHERN WI OVERNIGHT...THE FORECAST AREA REMAINS MAINLY IN THE WARM SECTOR OF THE STORM. THE ONLY AREA WHERE THIS IS NOT TRUE IS THE FAR NORTHWEST EDGE...FROM ALBERT LEA/KASSON MN...UP THROUGH WABASHA...TO NEAR ABBOTSFORD/MEDFORD WI. ENOUGH COLD AIR COULD FILTER IN LATER THIS EVENING TO ALLOW FOR A MIX WITH OR CHANGE OVER TO SNOW. STILL APPEARS THE HIGHEST THREAT FOR SIGNIFICANT ACCUMULATIONS OF 2-5 INCHES WILL LIE JUST BEYOND THE FORECAST AREA...BUT SOME SPOTS ALONG THE AFOREMENTIONED LINE COULD SEE SOME BRIEF ACCUMULATIONS UP AROUND AN INCH OR SO ON GRASSY AREAS AND OTHER EXPOSED SURFACES. THE MAIN UPWARD MOTION AND FORCING SHIFT EAST OF THE AREA DURING THE OVERNIGHT HOURS. THIS ALLOWS THE FRONT TO MOVE BACK SOUTHEAST AS A COLD FRONT...ALLOWING THE COLD AIR TO INVADE. BUT LOOKING AT THE MODEL SOUNDINGS...THIS COLD AIR ARRIVES JUST AS THE UPPER LEVEL CLOUD AND SUPPLY OF ICE FOR SEEDING THE LOW LEVELS MOVES AWAY. IF THE ICE CAN LINGER LONGER...WE MAY SEE A BIT MORE SNOW ACROSS THE REGION OVERNIGHT. BUT EVEN IF WE DO...IT LIKELY WILL NOT ADD UP TO MUCH. AND IF THE ICE INDEED DOES DEPART...SOUNDINGS SUPPORT DRIZZLE TO CONTINUE FOR SEVERAL HOURS. COULD SOME OF THIS MANIFEST AS FREEZING DRIZZLE? CERTAINLY IT COULD...WITH THE HIGHEST LIKELIHOOD OVER PARTS OF SOUTHEAST MN WEST OF ROCHESTER. FURTHER EAST...THE RAIN WILL TAPER OFF AND BECOME LIGHT...TRANSITIONING TO DRIZZLE AS WELL. THE ENTIRE SYSTEM EJECTS QUICKLY EASTWARD WEDNESDAY MORNING...SO THAT BY MID-DAY THE PRECIPITATION SHOULD BE ENDED. SKIES WILL THEN CLEAR FROM WEST TO EAST ACROSS THE REGION...WITH MAINLY CLEAR SKIES BY SUNSET. DESPITE THE CLEARING AND RESULTING SUNSHINE... THE ARRIVAL OF COOLER AIR WILL OFFSET THE WARMING EFFECTS OF THE SUN...SO NOT MUCH WARMING IS ANTICIPATED. .LONG TERM...(WEDNESDAY NIGHT THROUGH NEXT TUESDAY) 320 PM CST TUE NOV 5 2013 A LONG WAVE TROUGH OVER THE AREA WILL SHIFT TO THE EAST ON THURSDAY...WITH SURFACE HIGH PRESSURE BUILDING IN. THERE IS SOME CONCERN WITH CHANNELED VORTICITY DROPPING INTO THE BACK SIDE OF THE TROUGH COULD BRING MORE CLOUDINESS OVER WI THURSDAY...WITH THE OUTSIDE CHANCE OF A SPRINKLE GIVEN THE STEEP LAPSE RATES AND COOL AIRMASS IN PLACE. BUT THE ATMOSPHERE LOOKS PRETTY MOISTURE STARVED DURING THAT TIMEFRAME...SO WILL NOT INCLUDE ANY MENTION YET. THE NEXT SHORT WAVE TROUGH COMES ZIPPING THROUGH THE NORTHERN CONUS LATE FRIDAY INTO SATURDAY...FLATTENING THE UPPER RIDGE. MODELS HAVE BEEN STRUGGLING WITH THE LOCATION AND TIMING OF THIS FEATURE FOR SEVERAL DAYS NOW...AND TODAY NO DIFFERENT. AS THE MAIN SURFACE LOW CENTER PASSES WELL NORTH OF THE LOCAL AREA...OUR CHANCE FOR ANY PRECIPITATION WILL COME WITH THE WARM ADVECTION AHEAD OF THE LEADING WARM FRONT AS IT CROSSES FRIDAY NIGHT INTO EARLY SATURDAY. THE TRAILING COLD FRONT LOOKS TO MOVE THROUGH DURING THE DAY ON SATURDAY...BUT WITH NO FORCING ALONG IT...DOES NOT APPEAR TO BE A THREAT FOR ANY PRECIPITATION. MODELS REALLY DIVERGE WITH RESPECT TO ENERGY ROTATING AROUND A CANADIAN TROUGH BY LATE SUNDAY...ALTHOUGH THE LATEST 05.12Z ECMWF HAS COME MORE INTO LINE WITH THE GFS. DOES NOT APPEAR THERE WILL BE MUCH OF A PRECIPITATION THREAT...BUT A REINFORCING SHOT OF COOL AIR LOOKS TO INVADE FOR EARLY NEXT WEEK...POTENTIALLY SENDING TEMPERATURES ON A DOWNWARD TREND. WAS CONSERVATIVE ON THIS COOLING TREND AT THIS POINT WITH THE UNCERTAINTY. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING) ISSUED AT 542 PM CST TUE NOV 5 2013 LARGE AREA OF RAIN COVERING BOTH TAF SITES THIS EVENING WITH A VARIETY OF REPORTABLE CONDITIONS. THE VISIBILITY IN THE RAIN GENERALLY RANGES FROM 2 TO 4 MILES WHILE CEILINGS VARY FROM LESS THAN FIVE HUNDRED FEET UP TO VFR. LOOKING AT CONDITIONS DOWNSTREAM ACROSS NORTHERN IOWA...PRIMARILY IFR AND EITHER STARTED BOTH TAFS WITH IFR CONDITIONS OR MOVED THEM TO IFR WITHIN A COUPLE OF HOURS THIS EVENING. THESE CONDITIONS THEN EXPECTED TO PREVAIL INTO THE OVERNIGHT HOURS UNTIL THE SURFACE LOW OVER NORTHEAST KANSAS MOVES PAST THE AREA AND SWINGS THE WINDS AROUND TO THE NORTH/NORTHWEST. ONCE THIS HAPPENS...THE FORCING WILL BEGIN TO WEAKEN WHICH WILL ALLOW THE PRECIPITATION TO BECOME LIGHTER WITH SOME IMPROVEMENT IN THE VISIBILITY BUT NOT EXPECTING MUCH OF ANY CHANGE IN THE CEILING TO OCCUR AS THE LOW LEVELS LOOK TO REMAIN SATURATED. ENOUGH FORCING LOOKS TO LINGER INTO EARLY WEDNESDAY MORNING TO KEEP SOME DRIZZLE GOING. THE CONCERN AT KRST BECOMES WHETHER TEMPERATURES WILL BE WARM ENOUGH TO KEEP THIS AS LIQUID OR WHETHER THERE WILL BE A LITTLE BIT OF FREEZING DRIZZLE. NOT A LOT OF COLD AIR ON THE NORTH SIDE OF THIS SYSTEM CURRENTLY WITH SUB FREEZING TEMPERATURES CONFINED TO NORTHERN MINNESOTA AND NORTH DAKOTA INTO CANADA AND CONFIDENCE THAT THIS COLDER AIR WILL ARRIVE IN TIME FOR A SWITCH TO FZDZ IS NOT HIGH. BUT WITH BOTH THE 05.21Z RAP AND 05.18Z NAM SHOWING THIS POSSIBILITY...THOUGHT IT WAS BEST TO AT LEAST SHOW THIS FOR A SHORT PERIOD. CLEARING IS EXPECTED TO OCCUR BY LATE MORNING/EARLY AFTERNOON AS SOME WEAK RIDGING BUILDS IN PUSHING THE DEEPER MOISTURE OFF TO THE NORTHEAST. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...MW LONG TERM...MW AVIATION...04
AREA FORECAST DISCUSSION
NWS CARIBOU ME
1238 AM EST WED NOV 6 2013 .SYNOPSIS... HIGH PRESSURE WILL SLOWLY MOVE EAST OF THE REGION OVERNIGHT THROUGH WEDNESDAY. A COLD FRONT WILL APPROACH WEDNESDAY NIGHT AND CROSS THE REGION BY THURSDAY AFTERNOON. SURFACE HIGH PRES WILL THEN SLOWLY BUILD FROM THE SOUTHWEST TOWARD THE REGION FRIDAY AND SATURDAY WHILE AN UPPER LEVEL TROUGH CROSSES NORTHERN MAINE FROM QUEBEC ON FRIDAY. && .NEAR TERM /THROUGH WEDNESDAY/... 1230 AM UPDATE...ADJUSTMENTS NEEDED FOR THE TEMPERATURES AS THEY HAVE LEVELED OFF FOR THE TIME BEING GIVEN MID AND HIGH CLOUDS ARE MOVING ACROSS THE CWA. THIS IS IN RESPONSE TO WARMING IN THE UPPER LEVELS ESPECIALLY IN THE 800-700MB LAYER AS SEEN ON THE 00Z UA. TEMPERATURES COULD FALL BACK SOME ESPECIALLY IN THE LOW LYING AREAS BY 12Z AS SOME PARTIAL CLEARING SEEN ON THE IR SATL IMAGERY. CONCERN IS THERE FOR SOME LIGHT PRECIP WHICH COULD BE IN THE FORM OF SLEET OR -FZRA AS SEEN ON THE GFS SOUNDINGS W/A MOIST LAYER FROM 850-700MBS. ATTM, THE RUC WAS DOING THE BEST OUT OF THE MESOSCALE GUIDANCE IN SHOWING A GRADUAL WARMUP BY 7-8AM WHICH WOULD ALLEVIATE ANY FREEZING PRECIP. PREVIOUS DISCUSSION... INCREASING CLOUDS OVER THE NORTH LATE TONIGHT AND TOMORROW MORNING ASSOCIATED WITH A VERY WEAK UPPER LEVEL SHORTWAVE, THEN DECREASING CLOUDS LATE MORNING TO EARLY AFTERNOON, AND FINALLY INCREASING CLOUDS AGAIN LATE WEDNESDAY AFTERNOON AS THE SURFACE COLD FRONT APPROACHES FROM THE WEST. CONDITIONS LOOK TO BE DRY THROUGH WEDNESDAY AFTERNOON. CANNOT RULE OUT A SPRINKLE OR FLURRY WEDNESDAY MORNING WITH THE VERY WEAK SHORTWAVE. EXPECT MOST OF THE RAIN TO HOLD OFF UNTIL LATER WEDNESDAY NIGHT WITH THE MAIN COLD FRONT. && .SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/... TDY`S 12Z MODELS WERE IN VERY GOOD AGREEMENT WITH THE ONSET... DURATION AND EXIT OF SHWRS AHEAD OF A COLD FRONT THAT APCHS THE FA LATE WED NGT AND CROSSES BETWEEN MIDDAY AND LATE AFTN THU. TYPICAL...THE OPNL 12Z GFS IS ABOUT 3 TO 6 HRS FASTER THAN OTHER MODELS SUCH AS THE 12Z ECMWF...SO WE BLENDED THESE TMG DIFFERENCES RESULTING IN ERLY EVE EXIT POPS FOR OUR FA...WITH MEASURABLE PRECIP WRAPPING UP SIG BEFORE SFC TEMPS FALL TO AND BLO FZG LATE THU NGT AFT REACHING HI TEMPS OF 50S THU DYTM. TOTAL EVENT QPF FOR THIS EVENT BY MODEL CONSENSUS IS BETWEEN 2 AND 4 TENTHS OF AN INCH...ENOUGH TO JUSTIFY CATEGORICAL POPS WITHE CORE OF THIS EVENT...CAPPED TO 90 PERCENT TO REFLECT ANY REMAINING TMG UNCERTAINTY ATTM. AFT A BRIEF BREAK IN CLD CVR LATE THU NGT AND ERLY FRI MORN...AN UPPER LVL TROF FROM QB WILL BRING CLDNS PARTICULARLY FOR NRN/CNTRL PTNS OF THE FA...ALG WITH SCT AFTN/EVE SN SHWRS. BETWEEN THE LLVL COLD ADVCN WHICH WILL BE ACCOMPANIED BY WNW WINDS OF 15 TO 25 MPH AND CLD CVR...HI TEMPS FRI WILL BE AT LEAST 15 DEG COLDER THAN THU. .LONG TERM /LATE FRIDAY NIGHT THROUGH TUESDAY/... SLOW CLRG IS XPCTD ACROSS THE FA LATE FRI NGT INTO SAT MORN WITH SLOWLY DECREASING WINDS. NOT MUCH OPPORTUNITY FOR RADIATIONAL COOLING ANYWHERE OVR THE FA FRI NGT...WITH HI TEMPS SAT RECOVERING PERHAPS A DEG OR TWO WARMER THAN FRI DUE TO THE POTENTIAL OF GREATER SUNSHINE. AFT FAIR CONDITIONS SAT EVE...CLDS WILL BE ON THE INCREASE LATE SAT NGT AND ERLY SUN MORN AHEAD OF A FAST ZONAL CLIPPER S/WV FROM S CNTRL CAN. EITHER SN SHWRS OR A PD OF LGT SN WILL THEN COMMENCE MID TO LATE SUN MORN...MIXING WITH OR CHANGE TO RN OVR CNTRL AND SPCLY DOWNEAST AREAS SUN AFTN AS WEAK LLVL WARM ADVCN BRINGS A SHALLOW LLVL BL OF MARINE AIR NWRD FROM THE GULF OF ME. LATEST MODEL GUIDANCE SUGGESTS NOT MUCH MORE THAN A TENTH OF AN INCH OF TOTAL LIQUID EQUIV WITH THIS SYSTEM ATTM...SO EVEN IF THIS EVENT WERE ALL SN FOR NRN LOCATIONS...NOT MORE THAN AN INCH OF SNFL WOULD RESULT...BUT CANNOT RULE OUT SLICK ROADWAYS LATE SUN MORN IF THIS EVENT TMG HOLDS. AFT ANY REMAINING PRECIP ENDS ERLY SUN EVE...MDT LLVL COLD ADVCN WILL BRING COLDER AIR TO THE REGION BEGINNING LATE SUN NGT THRU TUE...PERHAPS COLDER THAN WHAT WE INDICATE THAN THIS UPDATE...WHICH WE WILL REFINE BASED ON FUTURE MODEL CONSISTENCY ON THE INTENSITY OF THE COLD AIRMASS. && .AVIATION /06Z WEDNESDAY THROUGH SUNDAY/... NEAR TERM: VFR CONDITIONS EXPECTED THROUGH WEDNESDAY AFTERNOON. THERE ARE SOME 4000 FOOT CEILINGS THIS AFTERNOON OVER COASTAL DOWNEAST, BUT EXPECT THESE TO RISE TONIGHT. ALSO, SITES FROM KPQI NORTH MAY SEE SOME CEILINGS IN THE 4000 TO 6000 FOOT RANGE LATE TONIGHT AND TOMORROW MORNING. SHORT TO LONG TERM: CIGS AND VSBYS WILL LOWER FROM LOW VFR WED EVE TO IFR BY THU MORN AS A PRE-COLD FRONTAL BAND OF SHWRS ENTERS THE REGION FROM QB. CIGS AND VSBYS WILL REMAIN IFR THRU THU...IMPROVING BACK TO VFR FOR DOWNEAST SITES AND TO MVFR NRN TAF SITES THU NGT BEHIND THE COLD FRONT. MVFR BKN-OVC SC WILL CONT ACROSS NRN TAF SITES FRI WHILE DOWNEAST SITES REMAIN VFR...THEN ALL SITES WILL BE VFR FRI NGT THRU SAT NGT. THE NEXT CHC OF MVFR/IFR WILL BE WITH SN SHWRS AND DOWNEAST RN/SN SHWRS ON SUN. && .MARINE... NEAR TERM: CONDITIONS WILL REMAIN BELOW SMALL CRAFT LEVELS THROUGH WEDNESDAY AFTERNOON, ALTHOUGH SOUTH WINDS WILL INCREASE TO AROUND 15 KNOTS WEDNESDAY AFTERNOON WITH COMBINED SEAS TO 4 FEET AS THE COLD FRONT APPROACHES. SHORT TO LONG TERM: SCA CONDITIONS SHOULD CONT THU WITH LONG FETCH SRLY COMPONENT SFC WINDS AND THEN BEHIND THE COLD FRONT LATER THU NGT INTO FRI NGT WITH BRISK NW WINDS. WINDS AND SEAS SHOULD THEN SUBSIDE BLO SCA CRITERIA LATER SAT...AND CONT SO THRU MON. WENT WITH A BLEND OF 12Z WW3...SWAN GFS...SWAN NAM AND SOME OF THE PREV FCST FOR WV HTS THIS UPDATE. && .CAR WATCHES/WARNINGS/ADVISORIES... ME...NONE. MARINE...NONE. && $$ NEAR TERM...HEWITT
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
1100 PM CST TUE NOV 5 2013 .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 338 PM CST TUE NOV 5 2013 COLD FRONT THAT SWEPT ACROSS THE AREA YESTERDAY HAS BECOME A WARM FRONT THIS AFTERNOON THAT STRETCHES FROM A 1010 MB SFC LOW OVER THE OK PANHANDLE NORTHEAST TO ABOUT SHEBOYGAN IN WISCONSIN. SPLAYED WEST TO EAST ACROSS THE CENTER OF THE MPX CWA IS 1025 MB RIDGE OF HIGH PRESSURE. WE HAVE SEEN SOME VERY DRY AIR BUILD IN AT THE SFC WITH THE HIGH...WITH DEW POINTS ACROSS WRN/CENTRAL MN DOWN INTO THE UPPER TEENS TO LOWER 20S. A 0.5 DEG REFLECTIVITY IMAGE AT 21Z SHOWS THE IMPACT OF THIS DRY LOW LEVEL AIR...WITH A NICE DONUT HOLE AROUND THE MPX RADAR. HOWEVER...REFLECTIVITY SOUTH AND WEST OF THE RDA IS LOWER THAN IT IS EAST AND NORTHEAST...SO YOU CAN GET THE SENSE OF HOW THE ATMOSPHERE IS QUICKLY MOISTENING SOUTH AND WEST OF THE TWIN CITES. REGIONAL RADAR RIGHT NOW SHOWS TWO ENHANCED AREAS OF REFLECTIVITY THIS AFTERNOON AND MOST MODELS SHOW THIS CURRENT TREND OF TWO ENHANCED AREAS OF QPF CONTINUING THROUGH MUCH OF THE EVENT. ONE AREA CAN BE BEST DESCRIBED AS A BLOB OF PRECIPITATION THAT CAN BE FOUND AT 21Z ACROSS MOST OF IOWA. THIS IS ON THE NOSE OF THE LLJ AND ITS ASSOCIATED THE MAIN MOISTURE SURGE. THE SECOND IS A BAND OF RADAR RETURNS THAT STRETCHES FROM NEAR NORTH PLATTE IN CENTRAL NEB...NORTHEAST THROUGH SIOUX FALLS AND CONTINUES ON COMPOSITE REFLECTIVITY NORTHEAST TO REDWOOD FALLS/BUFFALO/CAMBRIDGE AND EVENTUALLY OVER TO THE SPOONER WI AREA. THIS IS IN ASSOCIATION WITH ENHANCED FGEN ALONG WITH SOME CSI CENTERED AROUND 700 MB. YOU CAN SEE THE IMPACTS OF THESE TWO PIECES OF FORCING IN SEVERAL OF THE HI-RES MODELS. FOR INSTANCE...THE 05.18 HRRR SHOWS QPF OF 0.75-1.00 INCHES ACROSS SE MN WITH THE MAIN MOISTURE SURGE...A LULL IN TOTAL QPF FROM MANKATO UP THROUGH HASTINGS WHERE ONLY A QUARTER INCH OF QPF IS INDICATED...WITH THE CSI BAND SHOWING UP FROM REDWOOD FALLS THROUGH MINNEAPOLIS AND UP TOWARD RICE LAKE WHERE RUN TOTAL QPF IS UP MORE IN THE 0.5 INCH RANGE THANKS TO THE ENHANCED FGEN/CSI FORCING. FOR THE WINTER WEATHER ADVISORY...IT IS WHERE THIS FGEN BAND SETS UP THAT WILL RESULT IN THE 3-5 INCH SNOWFALL TOTALS THAT ARE EXPECTED. COUPLE OF THINGS THAT MAKE THIS SNOWFALL FORECAST DIFFICULT ARE NARROW NATURE OF THE EXPECTED FGEN BAND /NOT MUCH MORE THAN 50 MILES WIDE/ ALONG WITH HOW QUICKLY DO THE LOW LEVELS OF THE ATMOSPHERE COOL TO ALLOW RAIN TO CHANGE TO SNOW. ALTHOUGH WE ARE SEEING MANY PLACES IN THE TWIN CITIES WITH TEMPS IN THE 40S...IT IS THOSE DEW POINTS AND THE ATTENDANT WET BULB TEMPERATURES THAT YOU REALLY NEED TO PAY ATTENTION TO. BECAUSE OF THE DRY AIR...SFC WEB BULB TEMPS ARE IN THE LOW TO MID 30S...WHICH MEANS AS THE PRECIP EVAPORATES WE WILL QUICKLY SEE TEMPS FALL OFF TO NEAR THE FREEZING MARK...WITH A RAPID CHANGEOVER TO SNOW EXPECTED WEST OF A BLUE EARTH/WASECA/LADYSMITH LINE SHORTLY AFTER RAIN BEGINS. EAST OF THIS LINE...DEWPS ARE STILL MAINLY IN THE MID 30S. A GOOD EXAMPLE OF THIS RAPID CHANGEOVER WAS LITCHFIELD...WHICH FIRST REPORTED RAIN AT 230 PM AND WAS ALREADY REPORTING SNOW 20 MINUTES LATER. THE SPREAD AMONGST THE MODELS FOR WHERE THE 3-5 INCH BAND SETS UP WAS NOT ALL THAT LARGE...RANGING ON THE 05.12 RUNS FROM BEING CENTERED ALONG THE HENNEPIN/DAKOTA COUNTY LINE WITH THE NAM AND MORE ALONG THE HENNEPIN/WRIGHT COUNTY LINE WITH THE GFS/GEM. HRRR/HOPWRF/MPXWRF/ECMWF BASICALLY SPLIT THE DIFFERENCE BETWEEN THE TWO...AND THE CURRENT FORECAST FAVORS A BLEND OF THESE MODELS. THE ONE AREA IT LOOKS LIKE WILL NEED TO BE WATCHED FOR POSSIBLE WARNING TYPE SNOW /GREATER THAN 6 INCHES/ IS SW MN...WHERE THE SNOW IS ALREADY FLYING AND THE RESIDENCE TIME FOR THE FGEN BAND LOOKS TO BE THE LONGEST. HAVE LEFT THE WINTER WEATHER ADVISORY AS IS...THOUGH WOULD SAY THAT MOST OF MN COULD BE ENDED AROUND 9Z...WITH WI ENDING AT 12Z...ABOUT 3 HOURS AHEAD OF WHAT WE CURRENTLY HAVE. FOR AS MUCH FUN AS WE ARE GOING TO HAVE WITH THE PRECIP TONIGHT...WEDNESDAY IS LOOKING QUIET AND BEAUTIFUL...WITH MOSTLY SUNNY SKIES EXPECTED EVERYWHERE BY THE AFTERNOON. DID FAVOR THE FORECAST HIGHS FOR TOMORROW TOWARD A BLEND OF THE DETERMINISTIC MODELS...WHICH RESULTED IN THE COOLEST TEMPS /WITH HIGHS IN THE UPPER 30S/ ALONG WHERE THE BAND OF SNOW IS EXPECTED FOR TONIGHT. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 338 PM CST TUE NOV 5 2013 FOLLOWING WEDNESDAYS SYSTEM...ANOTHER WEAK CLIPPER SYSTEM RIDES SOUTHEAST IN THE NORTHWEST FLOW OVER THE AREA WEDNESDAY NIGHT. THIS WILL PROVIDE A FEW CLOUDS BUT IS EXPECTED TO MOVE THROUGH DRY. HIGH PRESSURE WILL DOMINATE THE WEATHER FOR THURSDAY...WITH SOME SUNSHINE AND NEAR NORMAL TEMPERATURES. MORE ZONAL FLOW REGIME DEVELOPS AND ANOTHER FAST MOVING TROUGH MOVES INTO THE AREA FOR FRIDAY INTO SATURDAY. THE 12Z ECMWF IS MORE AMPLIFIED WITH THIS TROUGH WHILE THE GFS IS LESS SO AND FARTHER NORTH. THE ECMWF HAS BEEN MORE CONSISTENT WITH THE DEEPER NATURE OF THE TROUGH...SO WILL FOLLOW THIS FOR NOW. STILL PROVIDES JUST A CHANCE OF MIXED TYPE PRECIPITATION FOR THE EVENT...MAINLY OVER THE NORTHERN CWA. LARGE HIGH PRESSURE SYSTEM FOLLOWS THIS TROUGH FOR SUNDAY...WITH THE GFS AND ECMWF DIVERGING ON OVERALL MOVEMENT OF THE NEXT WESTERN TROUGH INTO THE CWA. THE ECWMF IS FASTER WITH A STRONG COLD FRONT SUNDAY NIGHT DRAWING IN MUCH COLDER AIR OVER THE AREA INTO THE FIRST PART OF NEXT WEEK. THE GFS HOLDS OFF ON THIS COLD AIR INTRUSION UNTIL WEDNESDAY. STILL TIME TO DECIPHER MODEL TRENDS WITH THIS OVERALL DEVELOPMENT. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT) ISSUED AT 1032 PM CST TUE NOV 5 2013 SIGNIFICANT IMPROVEMENT TO THE CEILINGS AND VISIBILITIES WILL OCCUR AT KRWF AND KSTC BY 09Z AS THE BACK EDGE OF THE SNOW MOVES EAST ALONG WITH WINDS BECOMING NW. THE IMPROVEMENT WILL REACH INTO THE TWIN CITIES IN THE 10Z-12Z TIME FRAME. CIGS BLO 010 WITH VSBYS 1-3SM -SN WILL BE COMMON OVERNIGTH FOR KRNH AND KEAU WITH IMPROVEMENT BETWEEN 13Z AND 15Z. THEREAFTER VFR CONDITIONS WILL PERSIST THROUGH THE END OF THE TAF PERIOD WITH WINDS BACKING TO THE WSW BY EVENING. KMSP...MOST INTENSE BAND OF SNOW EXTENDS NE-SW ACROSS THE AIRFIELD ATTM WITH LIGHTER BANDS TO THE WEST. VSBYS PROBABLY WILL NOT DROP BELOW 1 1/2SM THROUGH THE DURATION OF THE SNOW EVENT...WHICH IS EXPECTED TO END AROUND 10Z. CEILINGS BETWEEN 500 AND 800 FEET BECOMING MVFR AFTER 10Z AND VFR BY 12Z. /OUTLOOK FOR KMSP/ THU...VFR. WINDS W 5-10 KTS. FRI...CHC FOR MVFR CIGS AND -RA. WINDS SE 10-15 KTS. SAT...VFR. WINDS NW 10-15 KTS. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...WINTER WEATHER ADVISORY UNTIL 6 AM CST WEDNESDAY FOR MNZ051>053- 059>063-065>070-073>078-082>085-091-092. WI...WINTER WEATHER ADVISORY UNTIL 9 AM CST WEDNESDAY FOR WIZ014>016- 023>025-027. && $$ SHORT TERM...MPG LONG TERM...DWE AVIATION...RAH
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1145 PM CST Tue Nov 5 2013 .UPDATE: Issued at 940 PM CST Tue Nov 5 2013 Tonight`s rain event is unfolding about as expected. Have made tweaks to bring categorical pops further north and east more quickly, but the general forecast is about the same. Should see the rain overspread the rest of the area through the 06-08Z as moderate to strong isentropic lift continues on the nose of the low level jet. Am monitoring the line of thunderstorms now in southeast Kansas to possibly bring thunder to the southern 1/2 of the CWFA. RAP forecasts up to 100 J/kg MUCAPE moving in ahead of the front so I can`t rule it out. However, lightning strikes are relatively few and far between right now and am thinking that ongoing rain will be enough to dampen any instability. Will leave mention of thunder out for now and continue to monitor. Carney && .SHORT TERM: (Through Wednesday) Issued at 205 PM CST Tue Nov 5 2013 Main shield of rain from this morning has lifted north as forecast, with only small batches of light rain and sprinkles streaming northeast within the warm sector. Low pressure currently located in north central Kansas will continue to advance northeast along the stalled front into Iowa and Wisconsin tonight. Trailing cold front will sweep east across Missouri and Illinois late tonight and Wednesday with a period of rain and falling temperatures expected. CVKING .LONG TERM: (Wednesday Night through Next Tuesday) Issued at 205 PM CST Tue Nov 5 2013 Pattern flattens out in the wake of this system with a dry and seasonal forecast remaining in tact despite a frontal passage on Saturday. Precipitation chances may eventually increase next week if better moisture can return ahead of a front poised to move across the Midwest on Monday. CVKING && .AVIATION: (For the 06z TAFs through 06z Wednesday Night) Issued at 1128 PM CST Tue Nov 5 2013 MVFR/IFR cigs draped across the w 2/3 of Missouri this evening have made very little ewd progression...with the leading edge of these lower conditions remaining q-stationary near a KUNO-KUIN line. Still expecting a general deterioration of conditions across the CWA overnight as several more waves of showers push across the region, but it may take several more hours before prevailing MVFR conditions settle into STL metro area. Have attempted to tie prevailing IFR cigs/vsbys to the time frame closer to fropa at most locations. In addition, weakening convection has managed to creep into west central MO, and believe some of this could reach KCOU over the next few hours. Given the recent decease in lightning strikes not certain how much of a thunder threat there will be elsewhere, so Will let oncoming shift monitor trends to determine if thunder should be added at other TAF locations in later updates. 00z guidance continues to support thinking that there should be a rapid improvement in conditions beginning several hours after fropa, as increasing northwest winds end precip and begin advecting in drier air that should erode low cloudiness. Specifics for KSTL: Several rounds of light rain should cause prevailing cigs and vsbys to dip into MVFR category during the predawn hours and persist into early Wednesday morning, with a brief drop to IFR cigs/vsbys occurring around the 15z fropa. A rapid improvement should then begin several hours after fropa, with low end MVFR cigs by midday, with these ceiling then lifting during the afternoon and scattering out by early Wednesday evening. Truett && .LSX WATCHES/WARNINGS/ADVISORIES: MO...NONE. IL...NONE. && $$ WFO LSX
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1136 PM CST TUE NOV 5 2013 .UPDATE... ISSUED AT 813 PM CST TUE NOV 5 2013 AS OF 02Z...RADAR RETURNS FROM KUEX INDICATE LITTLE IF ANY PRECIPITATION IS OCCURRING ACROSS OUR CWA. WATER VAPOR IMAGERY AND RAP DATA SUGGEST THE 700MB MID LEVEL SHORTWAVE TROUGH AXIS IS DIRECTLY OVERHEAD OUR CWA AT THIS HOUR...AND QUICKLY DEPARTING TO THE NORTHEAST. RADAR DATA FROM KLNX DOES INDICATE LIGHT PRECIPITATION OVER NORTH CENTRAL NEBRASKA...THE RESULT OF SUBTLE MID LEVEL DEFORMATION TO THE NORTHWEST OF THE MID LEVEL TROUGH AXIS. SOME OF THIS ACTIVITY COULD BRIEFLY MOVE ACROSS NORTHERN PORTIONS OF OUR CWA IN THE FORM OF LIGHT SNOW THROUGH 06Z. THAT BEING SAID...VERY LITTLE IF ANY SNOW ACCUMULATION IS EXPECTED WITH THIS ACTIVITY AND AS A RESULT...THE WINTER WEATHER ADVISORY...WHICH WAS IN EFFECT ACROSS OUR EXTREME NORTHWEST...WAS CANCELLED. UPDATED FORECAST GRIDS TO REMOVE POPS THROUGH THE REMAINDER OF THE NIGHT. THE GOING FORECAST WAS IN GREAT SHAPE OTHERWISE...WITH ONLY A FEW ADDITIONAL TWEAKS MADE TO HOURLY TEMPERATURE...SKY...WIND...AND DEW POINT GRIDS TO BETTER REFLECT CURRENT OBSERVATIONS. && .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 255 PM CST TUE NOV 5 2013 THE PRECIPITATION EVENT TODAY IS GENERALLY UNFOLDING AS EXPECTED WITH WIDESPREAD RAINFALL DURING THE MORNING...AND A CHANGE TO SNOW IN OUR W/NW BY MID/LATE MORNING. SEVERAL LOCATIONS PICKED UP AT LEAST ONE HALF OF AN INCH WHILE OTHER REPORTS OF OVER ONE INCH HAVE BEEN RECEIVED. THE RAIN HAS MIXED WITH AND MADE THE SWITCH TO SNOW FROM ROUGHLY THE GOTHENBURG AREA NORTHEASTWARD TO ARCADIA/ORD/GREELEY EARLY THIS AFTERNOON. THE RAP HAS BEEN HANDLING THE ONGOING/SHORT TERM TIME FRAME WELL AND HAVE FOLLOWED CLOSE TO THIS THROUGH THE EVENING. THE MID LEVEL TROUGH WILL CONTINUE TO TRANSLATE EASTWARD ACROSS THE INTERIOR CONUS THROUGH THE REMAINDER OF THE AFTN/EARLY EVENING. ISENTROPIC LIFT AHEAD OF THE SYSTEM WILL SHIFT EASTWARD DURING THE NEXT SEVERAL HOURS WITH MAIN RAIN AREA SHIFTING OFF TO THE EAST ACROSS EASTERN KS AND NEB. THE MID LEVEL H7 CIRCULATION TENDS TO INTERMITTENTLY CLOSE AS IT LIFTS TO NORTHEAST NEBRASKA WITH THE MAIN SNOW BAND/PSEUDO DEFORMATION REMAINING TO THE WEST/NORTHWEST OF OUR CWA. THIS BEING SAID...A FRONTOGENETIC BAND OF PCPN IS STILL EXPECTED INTO THE EVENING AS THE COLD FRONT ADVANCES SOUTHEASTWARD. AS THE COLDER AIR WORKS SOUTH...THE LINGERING RAIN WILL MIX WITH AND/OR CHANGE TO SNOW WITH THE TRANSITION TO ALL SNOW EXPECTED TO AFFECT LOCATIONS WEST OF A LINE FROM GENOA TO HASTINGS TO FRANKLIN FOR A BRIEF TIME. THE GREATER SNOW ACCUMULATIONS WILL REMAIN ACROSS OUR NW/W CWA...WHERE CURRENTLY A WINTER WEATHER ADVISORY IS IN EFFECT UNTIL MIDNIGHT. SNOWFALL IN THE ADVISORY AREA IS EXPECTED TO RANGE FROM 1 TO 3 INCHES...MAINLY ON GRASSY SURFACES AND LOCALLY HIGHER AMOUNTS CANNOT BE RULED OUT IF A SNOW BAND SETS UP THIS EVENING. THE LAST SNOW REPORT RECEIVED FROM THE ORD AREA EARLY THIS AFTERNOON HAD A SNOW ACCUMULATION OF JUST OVER ONE INCH. OUTSIDE OF THE ADVISORY AREA...LITTLE IF ANY SNOW ACCUMULATION IS EXPECTED. THE SNOW WILL RAPIDLY WIND DOWN DURING THE EVENING BEHIND THE PASSING MID LEVEL TROUGH AXIS. HAVE ENDED PCPN BY 06Z...BUT OUR FAR NORTH MAY SEE A FEW FLURRIES FOR AN HOUR OR SO. DRY AND COOLER CONDITIONS ARE FORECAST FOR WEDNESDAY IN THE WAKE OF THIS SYSTEM. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 255 PM CST TUE NOV 5 2013 WEDNESDAY NIGHT THROUGH TUESDAY. MAIN CONCERN WILL BE TEMPERATURES THROUGH PERIOD AND IF THERE WILL BE ANY PRECIPITATION NEXT TUESDAY. NORTHWEST FLOW WILL START THE PERIOD WITH A GRADUAL TRANSITION TO ZONAL FLOW TOWARD THE WEEKEND. THERE ARE VERY FEW UPPER LEVEL WAVES EXPECTED TO MOVE THROUGH THE AREA. AT THE SURFACE THERE IS A HIGH PRESSURE SYSTEM FOR WEDNESDAY NIGHT INTO THURSDAY THAT WILL MOVE TO THE EAST THURSDAY NIGHT. EXPECT DRY CONDITIONS WITH COOL TEMPERATURES WEDNESDAY NIGHT AND THURSDAY. WHEN THE SURFACE HIGH MOVES OFF TO THE EAST THURSDAY NIGHT THERE IS A LITTLE WARM ADVECTION AND TEMPERATURES WILL BE A LITTLE WARMER FOR THURSDAY NIGHT. THE WARMER TEMPERATURES WILL CONTINUE INTO FRIDAY...BUT WILL BE TEMPERED BY BREEZY CONDITIONS. THE PRESSURE GRADIENT TIGHTENS ON FRIDAY AND WITH WINDS ALOFT OF OVER 40 KTS EXPECT AT LEAST BREEZY CONDITIONS. A COLD FRONT WILL MOVE THROUGH THE FORECAST AREA FRIDAY NIGHT AND BRING A LITTLE BIT COOLER TEMPERATURES TO THE AREA FOR SATURDAY AND SUNDAY. EARLY NEXT WEEK THERE ARE VARYING SOLUTIONS WITH REGARD TO WHAT IS EXPECTED. BOTH THE GFS AND THE ECMWF HAVE NEARLY ZONAL FLOW. WITH SOUTH WINDS THE GFS BRINGS ADDITIONAL MOISTURE INTO THE AREA AND WITH WARM ADVECTION THERE COULD BE SOME LIGHT RAIN ON TUESDAY. THE ECMWF ON THE OTHER HAND HAS EAST WINDS AND KEEPS THE MOISTURE TO THE SOUTH OF THE FORECAST AREA AND DRY CONDITIONS. HAVE WENT A LITTLE CLOSER TO THE GFS AT THIS TIME AND HAVE A LITTLE LIGHT RAIN MAINLY IN THE SOUTHEAST PART OF THE AREA. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT) ISSUED AT 1126 PM CST TUE NOV 5 2013 MAIN FORECAST CONCERN LIES WITH LOW LEVEL STRATUS THROUGH THE REMAINDER OF THE OVERNIGHT HOURS. MANY AREA OBS SHOWING MVFR CEILINGS REMAINING IN PLACE...AND EXPECT THAT CONTINUE FOR AT LEAST A FEW MORE HOURS...BUT THOSE CLOUDS SHOULD DRIFT EAST WITH TIME. ONCE THEY DO...VFR CONDITIONS ARE FORECAST. NORTHWESTERLY WINDS CURRENTLY IN PLACE WILL GRADUALLY BECOME MORE WESTERLY THIS MORNING...WITH THOSE WESTERLY WINDS REMAINING IN PLACE THROUGH THE END OF THE PERIOD. && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$ UPDATE...BRYANT SHORT TERM...FAY LONG TERM...JCB AVIATION...ADO
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1128 PM CST TUE NOV 5 2013 .AVIATION...06Z TAFS FOR KOFK...KLNK AND KOMA. IFR CIGS WILL LINGER ACROSS EASTERN NEBRASKA INTO THE MORNING WITH SOME IMPROVEMENT ABOVE FL010 BETWEEN 14Z AND 18Z. A BAND OF DRIZZLE WILL AFFECT KOMA AND KLNK THROUGH 10-12Z...DROPPING VSBYS TO 3 MILES AT TIMES. GUSTY NORTHWEST WINDS 15 TO 25KT WILL GRADUALLY DIMINISH THROUGH THE MORNING AS WELL. EXPECT VFR CONDITIONS AND CLEARING SKIES AFTER 20Z. DERGAN && .PREV DISCUSSION... /ISSUED 900 PM CST TUE NOV 5 2013/ UPDATE... WITH SNOW PRETTY MUCH DISSIPATING ACROSS NORTHEAST NEBRASKA...HAVE CANCELLED THE WINTER WEATHER ADVISORY. THERE COULD BE SOME LIGHT SNOW THERE LATER THIS EVENING OR OVERNIGHT AS DEFORMATION ZONE ROTATES IN FROM NORTH CENTRAL NEBRASKA...BUT WOULD EXPECT THIS AREA TO DIMINISH AS IT MOVES EAST. ALSO...ADDITIONAL AMOUNTS SHOULD BE MINIMAL. DERGAN PREV DISCUSSION... /ISSUED 303 PM CST TUE NOV 5 2013/ SHORT TERM...TONIGHT THROUGH FRIDAY. UPPER TROUGH TO OUR WEST CONTINUES TO WORK SLOWLY EAST PER AFTERNOON STLT IMAGERY. THIS SYSTEM HAS BEEN VERY EFFICIENT IN GENERATING PRECIP ACROSS THE FORECAST AREA TODAY...SOME LIQUID AMOUNTS HAVE PUSHED PAST 1 INCH...AS IT PRODUCED DECENT FRONTOGENETICAL FORCING WHICH TAPPED DECENT LOWER LEVEL MOISTURE. THIS IS/WAS DESPITE ANEMIC UPPER HGT FALLS...20-40M AT H5. SHORT TERM QPF FROM 4KM WRF/RAP AND HRRR CONTINUE TO LIFT PRECIP ENE WITH IT EXITING SWRN ZONES NOT TOO LONG AFTER THE 00Z-03Z TIME PERIOD WITH A DEFORMATION BAND OF DWINDLING PRECIP PROBABLY LINGERING OVER NERN NEBR ALL NIGHT AND POSSIBLY SOME TRACE FLURRIES YET IN THE MORNING. BASED ON CURRENT STLT/RADAR TRENDS THIS LOOKS REASONABLE. WILL LEAVE WINTER WEATHER HEADLINE ALONE FOR THIS EVENING ALTHOUGH ACCUMULATIONS THUS FAR ON SERN EDGE OF ADVISORY HAVE BEEN MOSTLY LIMITED TO GRASSY SURFACES AND GENERALLY LESS THAN FORECAST DUE TO WARM GROUND AND SFC TEMPS AT OR A LITTLE ABOVE FREEZING. WITH APPROACHING NIGHTFALL...SNOW ACCUMULATIONS SHOULD BE A LITTLE MORE EASILY TO COME BY BUT MOST ADDITIONAL SHOULD BE AN INCH OR TWO...OR LESS...AFT 00Z. THE RAIN/SNOW MIX MAY MAKE IT TO OMAHA/LINCOLN BUT IT APPEARS COLDER AIR SUPPORTING THE CHANGEOVER WILL BE ARRIVING ABOUT THE SAME TIME THE PRECIP ENDS AT THOSE CITIES. OTHERWISE...FORECAST IN THE SHORTER TERM IS MAINLY TEMPERATURE DRIVEN AND LITTLE CHANGES WERE MADE TO FORECAST HIGHS WED THROUGH FRIDAY. DID BUMP THEM UP A FEW DEGREES SOUTH ON WED WHERE GROUND WILL BE ABSENT ANY SNOW AS WIND DIRECTION...NW SHIFTING TO WSW WILL BE FAVORABLE FOR MIXING. BUT IF CLOUDS FAIL TO CLEAR...WHICH WAS NOT EXPECTED...HIGHS WOULD BE A BIT COOLER. ANY RESIDUAL SNOW COVER WILL HAVE A DWINDLING IMPACT ON HIGHS THURSDAY AND ESPECIALLY BY FRIDAY NORTH...WHICH WAS REFLECTED IN PREV FORECAST AND LOOKED GOOD BASED ON LATEST FORECAST SOUNDINGS. MAIN CHANGE BEYOND WEDNESDAY WAS TO LOWER LOWS A CATEGORY OR SO THURSDAY NIGHT ESPECIALLY E...AS RETURN FLOW WILL PROBABLY SET UP TOO LATE TO KEEP MANY TEMPS FROM DROPPING TOWARD THE MID/UPPER 20S THAT GUIDANCE FORECAST. CHERMOK LONG TERM...FRIDAY NIGHT THROUGH TUESDAY. MEDIUM RANGE MODELS LEAVE LITTLE TO BE DESIRED IN THE EXTENDED PDS WITH GREAT VARIATION SEEN BTWN THE ECM/GFS/CMC. THUS MAKING TEMP FCST AS WELL AS POTENTIAL PCPN MON NIGHT/TUES EXTREMELY PROBLEMATIC AT BEST. AS OF NOW...LATEST ECM PROGS LARGE SCALE FLOW TRANSITIONING FROM ZONAL TO DEVELOPING TWO SIGNIFICANT SHORTWAVE TROFS...ONE OVER THE PAC NW AND THE OTHER OVER THE GREAT LAKES THUS FAVORING A COLD PATTERN ACROSS THE CNTRL CONUS. THE GFS ON THE OTHER BASICALLY MAINTAINS RELATIVELY ZONAL FLOW. MEANWHILE THE CMC DIGS AN UPPER TROF THRU THE GREAT BASIN WITH SW FLOW ALOFT PREVAILING. COMPARISON OF MAX/MIN TEMPS BTWN THE 05/00Z ECMMOS AND 05/12Z MEX CLEARLY SHOWING THE DISTINCTION. HIGHS PROGGED NEXT TUES AT KOMA...ECM MOS 36/MEX 49. GIVEN THAT THE ECM HAS PROVEN TO OUT PERFORM ON A REGULAR BASIS...FEEL COMPELLED TO TREND TOWARD THE COOLER SOLUTION. AS FOR POSSIBLE PCPN MON NIGHT/TUES...WILL AGAIN OPT TO GO WITH THE DRIER ECM. DEE && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && $$
AREA FORECAST DISCUSSION...UPDATED
NWS ALBUQUERQUE NM
1038 PM MST TUE NOV 5 2013 .AVIATION... 06Z TAF CYCLE BACK DOOR COLD FRONT CONTINUES TO SLIDE DOWN THE EASTERN PLAINS AND SHOULD BE REACHING ROSWELL SHORTLY...WITH SOME BRIEF GUSTS POSSIBLE. OTHERWISE...QUIET NIGHT IN STORE WITH VFR CONDITIONS PREVAILING. LOCALLY BREEZY CONDITIONS WITH GUSTS BTW 25-30KTS IN NW FLOW POSSIBLE AROUND KCQC WEDNESDAY AFTN. 34 && .PREV DISCUSSION...247 PM MST TUE NOV 5 2013... IMPRESSIVE WEATHER SYSTEM THAT HAS IMPACTED THE REGION OVER ROUGHLY THE PAST 18 HOURS IS BEGINNING TO MOVE OUT OF THE AREA. INSTABILITY SHOWERS CONTINUE OVER CENTRAL AND WESTERN NM HOWEVER THESE WILL QUICKLY DIMINISH AROUND SUNSET AS A POTENT DRY SLOT SHIFTS EAST INTO THE AREA. A BACK DOOR FRONTAL BOUNDARY HAS SHIFTED INTO THE NORTHEAST AND TEMPS ARE PLUMMETING ON GUSTY NORTH WINDS. LATEST HRRR AND RUC GUIDANCE WITH SUPPORT FROM SREF INDICATES THE POTENTIAL OR A SMALL BAND OF SNOW ALONG THE EAST SLOPES OF THE SANGRES BETWEEN RED RIVER AND RATON PASS...AND FROM NEAR DES MOINES/CAPULIN EAST TO CLAYTON FOR A FEW HOURS THIS EVENING. HAVE FOCUSED CHANCE POPS IN THIS AREA. THE MAIN FOCUS WILL SHIFT TO VERY COLD TEMPS TONIGHT AS A STRONG 1035MB HIGH PRESSURE CENTER BUILDS OVER COLORADO AND EXCEPTIONALLY DRY AIR INVADES THE STATE. 20Z OBS ACROSS THE NW CORNER AND AROUND SW COLORADO ALREADY HAVE FALLEN INTO THE LOWER TEENS. CLEAR SKIES ON TAP WILL LEAD TO IMPRESSIVE RADIATIONAL COOLING. HIGH WEDNESDAY WILL REMAIN NEAR 5 TO 10F WITH LIGHTER WINDS AND MORE SUN MAKING IT FEEL A LITTLE WARMER THAN TODAY. WEDNESDAY NIGHT WILL SEE EVEN STRONGER TEMPERATURE INVERSIONS ACROSS THE AREA. WOULD NOT BE SURPRISED TO SEE THE RANGE OF MIN TEMPS WITHIN THE ABQ METRO ON THE ORDER OF 20+ DEGREES BETWEEN THE VALLEY AND FOOTHILLS. A FAST MOVING DRY UPPER LEVEL TROUGH WILL SWING ACROSS COLORADO AND INCREASE WESTERLY WINDS OVER EASTERN NM. DOWNSLOPING WILL LEAD TO MODIFYING TEMPS WITH READINGS NOW 5 TO 10F ABOVE NORMAL. NEUTRAL TO VERY WEAK COLD ADVECTION BEHIND THIS WAVE WILL BE QUICKLY REPLACED BY WARM ADVECTION AS THE FLOWS SHIFTS MORE TO THE SOUTHWEST. THE WEEKEND AND EARLY NEXT WEEK LOOK VERY NICE AS TEMPS MODIFYING ABOVE NORMAL FOR THE ENTIRE AREA. GUYER .FIRE WEATHER... A FEW SNOW SHOWERS WILL BE POSSIBLE FROM THE SANGRE DE CRISTO MOUNTAINS EASTWARD THIS EVENING AS AN UPPER LEVEL TROUGH EXITS THE AREA TO THE EAST. ONLY LIGHT ADDITIONAL ACCUMULATION IS EXPECTED. IN ADDITION...A GUSTY BACK DOOR COLD FRONT WILL DROP SOUTHWARD THROUGH THE EASTERN PLAINS TONIGHT. WITH A LOW AMPLITUDE RIDGE OF HIGH PRESSURE ALOFT MOVING IN FROM THE WEST...HIGH TEMPERATURES ALONG AND WEST OF I-25 ARE EXPECTED TO WARM A FEW TO 11 DEGREES ON WEDNESDAY COMPARED TO TODAYS READINGS. FARTHER EAST...READINGS SHOULD FALL A FEW TO 11 DEGREES DUE TO THE BACK DOOR COLD FRONT. WIDESPREAD POOR VENTILATION IS ALSO EXPECTED WEDNESDAY...EXCEPT FOR THE EAST SLOPES OF THE CENTRAL MOUNTAIN CHAIN AND THE NORTHEAST PLAINS WHERE BETTER VENTILATION IS EXPECTED DUE TO A WEAK LEE TROUGH. VENTILATION SHOULD IMPROVE IN MOST LOCATIONS THURSDAY AS TEMPERATURES RISE A FEW TO 9 DEGREES...EXCEPT FROM ALBUQUERQUE TO GALLUP...FARMINGTON AND CHAMA WHERE A BROAD AREA OF POOR VENTILATION SHOULD PERSIST AS THE LOW AMPLITUDE RIDGE OF HIGH PRESSURE CROSSES ALOFT. ANOTHER UPPER LEVEL TROUGH WILL PASS NORTH OF NEW MEXICO FRIDAY CAUSING WESTERLY MOUNTAIN TOP WINDS TO STRENGTHEN TO 20-35 KTS WHILE A SHARP LEE TROUGH DEVELOPS AT THE SURFACE. SURFACE WINDS SHOULD BECOME GUSTY WITH DECENT VENTILATION AREAWIDE. SURFACE WINDS SHOULD BE BREEZIEST IN THE SANGRE DE CRISTO MOUNTAINS AND ACROSS PARTS OF THE EAST CENTRAL AND NORTHEAST PLAINS. IN THE WAKE OF THIS UPPER LEVEL TROUGH...TEMPERATURES SHOULD FALL A FEW TO 9 DEGREES ACROSS THE EAST ON SATURDAY AS A WEAK BACK DOOR COLD FRONT SAGS SOUTHWARD THROUGH THE PLAINS. POOR VENTILATION MAY ALSO BECOME WIDESPREAD AGAIN ON SATURDAY AS WINDS WEAKEN ALOFT AND AT THE SURFACE. POOR VENTILATION IS EXPECTED TO LINGER ACROSS NORTHERN...CENTRAL AND WESTERN AREAS ON SUNDAY AS THE FLOW ALOFT BEGINS TO TURN A BIT OUT OF THE SOUTHWEST IN RESPONSE TO A DEEPENING LOW PRESSURE SYSTEM OFF THE PACIFIC NW COAST. TEMPERATURES SHOULD ALSO REBOUND ABOVE NORMAL AGAIN AFTER SATURDAYS BRIEF COOL DOWN ON THE PLAINS. 44 && .ABQ WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
1104 PM CST TUE NOV 5 2013 .AVIATION... WILL CONTINUE WITH THE IFR CEILINGS OVERNIGHT UNTIL FROPA. SHRA ACTIVITY STARTING TO INCREASE IN AREAL COVERAGE SO WILL CHANGE THE -DZ TO -RA...NOT MUCH DIFFERENCE. THUNDER STILL LOOKS LIKE A VERY LOW PROBABILITY AND TAFS WILL CONTINUE TO HAVE NO MENTION OF TSRA. WILL ADJUST FROPA TIMING UP TO 11Z IN METROPLEX AND 13Z IN WACO BASED ON LATEST RAP SOUNDINGS. 84 && .PREV DISCUSSION... /ISSUED 248 PM CST TUE NOV 5 2013/ A BROAD AREA OF LIGHT RAIN CONTINUES TO STREAM NORTHEAST ACROSS THE CWA THIS AFTERNOON. LIKELY POPS WILL CONTINUE IN THE FORECAST THIS AFTERNOON FOR THE NORTHEASTERN QUADRANT OF THE CWA THROUGH 00Z AND WILL THEN TRANSITION THE LIKELY POPS EVEN FARTHER NORTHEAST BETWEEN 00Z AND 06Z. THIS RAIN SHIELD IS IN RESPONSE TO CONTINUED WEAK WARM-AIR ADVECTION AND WILL LIKELY REMAIN WITHOUT ANY THUNDERSTORMS. THE FOCUS WILL THEN TURN TO THE COLD FRONT EXPECTED TO MOVE INTO NORTH TEXAS TOMORROW MORNING. AT 2 PM...THE FRONT WAS JUST ABOUT TO ENTER THE TEXAS PANHANDLE. GUIDANCE IS CONSISTENT WITH THE FRONT ENTERING OUR NORTHWESTERN COUNTIES JUST BEFORE 3 AM. IT WILL THEN PUSH THROUGH THE METROPLEX BETWEEN 6 AND 8 AM...THEN REACH WACO/TEMPLE/KILLEEN AROUND 9 AM AND THEN THROUGH THE REST OF THE CWA BY NOON. AHEAD OF THE FRONT SCATTERED SHOWERS WILL LIKELY CONTINUE TONIGHT AS WEAK ISENTROPIC LIFT CONTINUES. EXPECT A WEAK LINE OF SHOWERS AND PERHAPS A THUNDERSTORM TO DEVELOP ALONG THE FRONT LATER TONIGHT IN OKLAHOMA. THIS LINE OF PRECIP WILL CONTINUE THROUGH MUCH OF THE CWA AS THE FRONT PROGRESSES THROUGH THE CWA. THE TTU WRF HAS BEEN CONSISTENTLY FORECASTING VERY LITTLE RAIN OVERNIGHT WITH THE FRONT...AND THIS IS SOMEWHAT WORRISOME. EVEN THOUGH IT DOES SHOW LESS ACTIVITY...RAIN CHANCES ARE STILL HIGH...BUT RAIN AMOUNTS WOULD SUFFER IF THIS SOLUTION VERIFIES. LOW AND HIGH TEMPERATURES TONIGHT AND TOMORROW WILL BE HIGHLY DEPENDENT ON THE FRONTAL PASSAGE AS TEMPERATURES SHOULD DECREASE IMMEDIATELY BEHIND THE FRONT WITH TEMPERATURES TOMORROW AFTERNOON HOLDING STEADY IN THE 50S TO NEAR 60 DEGREES. ALL PRECIP SHOULD BE ENDED BY LATE AFTERNOON AND A QUIET NIGHT IS EXPECTED. TEMPERATURES BY THURSDAY MORNING SHOULD BE QUITE COLDER WITH MID TO UPPER 30S LIKELY ACROSS THE NORTHERN AND NORTHWESTERN ZONES. WITH LIGHT WINDS...PATCHY FROST MAY BE POSSIBLE FOR THESE LOCATIONS. HIGHS THURSDAY WILL REBOUND INTO THE MIDDLE TO UPPER 60S WITH MOSTLY CLEAR SKIES. THE WEATHER PATTERN WILL TRANSITION TO NEARLY ZONAL FLOW IN THE CENTRAL PLAINS WITH WEAK SOUTHWEST FLOW OVER TEXAS BEGINNING FRIDAY. THIS SOUTHWEST FLOW WILL ALLOW SEVERAL WEAK DISTURBANCES TO TRANSLATE ACROSS NORTH TEXAS. THE FIRST IS EXPECTED FRIDAY NIGHT AND SATURDAY...BUT MOISTURE IS EXPECTED TO BE TOO LIMITED FOR ANY PRECIP TO REACH THE GROUND. ANOTHER WILL ARRIVE FOR MONDAY/TUESDAY AND MOISTURE SHOULD BE SUFFICIENT FOR SOME RAIN AND WILL INTRODUCE 20 POPS IN THE FORECAST. HAMPSHIRE && .PRELIMINARY POINT TEMPS/POPS... DALLAS-FT. WORTH, TX 57 62 42 67 45 / 100 50 0 0 5 WACO, TX 63 66 40 68 42 / 90 60 5 5 5 PARIS, TX 60 62 36 64 40 / 100 70 10 0 5 DENTON, TX 55 61 37 65 39 / 100 40 0 0 5 MCKINNEY, TX 58 61 37 64 41 / 100 50 0 0 5 DALLAS, TX 58 63 43 66 46 / 100 50 5 0 5 TERRELL, TX 62 64 41 64 42 / 100 60 5 0 5 CORSICANA, TX 63 68 42 66 44 / 90 60 5 5 5 TEMPLE, TX 64 68 40 66 43 / 80 60 10 5 5 MINERAL WELLS, TX 51 62 37 66 39 / 80 40 0 0 5 && .FWD WATCHES/WARNINGS/ADVISORIES... NONE. && $$ /
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
334 AM CST WED NOV 6 2013 .SHORT TERM...(TODAY AND TONIGHT) 333 AM CST WED NOV 6 2013 MAIN FORECAST CONCERNS THIS PACKAGE...EXITING RAIN/DZ/SOME -SN THIS MORNING...CLOUD TRENDS THIS AFTERNOON...TEMPERATURES. 06Z DATA ANALYSIS HAD AN AREA OF LOW PRESSURE CENTERED NEAR OELWEIN IA...LIFTING QUICKLY NORTHEAST ALONG A FRONT FROM NEAR KGRB TO KALO. STRONGEST OF THE SFC-700MB FORCING/LIFT WAS TRANSLATING QUICKLY NORTHEAST WITH THE LOW...WITH PRECIP ALREADY TAPERING OFF/ ENDING ACROSS THE WEST 1/3 OF THE FCST AREA. DEFORMATION BAND OF MAINLY -SN WEST/NORTH OF THE FCST AREA WAS DECREASING AS WELL. TEMP GRADIENT ACROSS THE FRONT QUITE IMPRESSIVE EARLY THIS MORNING...WITH MID 50S INTO SOUTHWEST WI AHEAD OF IT TO UPPER 30S/LOW 40S ONLY 30 MILES NORTHWEST OF THE BOUNDARY. DECREASING CLOUDS/CLEARING ALREADY SPREADING INTO WESTERN MN. MODEL RUNS OF 06.00Z INITIALIZED VERY WELL AND OFFER A TIGHT CONSENSUS OF SOLUTIONS FOR TODAY/TONIGHT. THIS TIGHT CONSENSUS AGAIN FAVORS THE FASTER OF THE EARLIER RUNS AS THE PLAINS TROUGH QUICKLY SWINGS THRU THE REGION TODAY. TREND APPEARS A BIT WEAKER WITH THE NORTHWEST FLOW SHORTWAVE TO DROP DOWN THE WEST SIDE OF THE BROADER TROUGH AND INTO MN TONIGHT. CHECK OF OBS VS. MODEL DATA AT 06Z SHOWED ALL TO BE REASONABLE WITH THE NORTHEAST IA SFC LOW. MODELS QUITE GOOD WITH THE SHARP TEMP CONTRAST ACROSS THE FRONT THRU WI/IA. MODELS ALL TRENDING WELL WITH THE BULK OF THE PRECIP SHIFTING EAST OF THE AREA. PER WV IMAGERY ALL APPEARED GOOD WITH THE MID LEVEL TROUGH/SHORTWAVE ENERGY PROGRESSING RATHER QUICKLY ACROSS THE CENTRAL/NORTHERN PLAINS. GIVEN THE TIGHTENING CONSENSUS AND NO GLARING ERRORS...FAVORED THE MODEL/ENSEMBLE CONSENSUS WITH SHORT TERM FCST CONFIDENCE REMAINING GOOD. FASTER TREND OF MODEL CONSENSUS CONTINUES TO SHIFT THE DEEPER MOISTURE/LIFT EAST OF THE AREA MORE QUICKLY THRU THIS MORNING... WITH THE FCST AREA NOW LOOKING TO BE PRECIP-FREE BY 18Z. HAVE TRENDED FCST GRIDS FOR THE FASTER PRECIP EXIT. WITH DECREASING DEPTH OF MOISTURE AND LOSS OF ICE IN THE CLOUDS...CARRIED ANY PRECIP THIS MORNING AS DRIZZLE. BIGGER QUESTION TODAY IS HOW QUICKLY WILL SUNSHINE RETURN TO THE FCST AREA. STRONG MODEL SIGNAL/CONSENSUS FOR DEEP/STRONG DRYING TO SPREAD ACROSS THE FCST AREA IN DEEP SUBSIDENCE BEHIND THE 850-500MB TROUGH AXIS PASSAGE. MODEL SOUNDINGS/X-SECTIONS SHOW THIS TO NEAR A KMDZ-KLSE- STRAWBERRY POINT IA LINE BY 18Z. GIVEN OBS/SATELLITE TRENDS OVER WESTERN MN...THIS SEEMS QUITE REASONABLE AND TRENDED GRIDS FOR MORE RAPID CLEARING TODAY. CLEAR/MOSTLY CLEAR SKIES EXPECTED ACROSS THE ENTIRE FCST AREA BY LATE AFTERNOON. SUNSHINE THIS AFTERNOON WILL OFFSET THE LOW LEVEL COLD ADVECTION WITH NEARLY STEADY TEMPS THIS AFTERNOON. MIXING TO 925-900MB TODAY...FOR SOME BRISK NORTHWEST WINDS IN THE WAKE OF THE LOW. SHORTWAVE DROPPING INTO MN TONIGHT BRINGS WITH IT SOME MOISTURE BETWEEN 850-700MB. SFC REFLECTION WITH THIS FEATURE WEAKENS THRU THE NIGHT AND ANY SFC-700MB FORCING/LIFT IS QUITE WEAK. LITTLE MORE THAN SCT-BKN 5K-8K FT CLOUDS EXPECTED. WITH WEAKER WINDS AS THE WEAK SFC TROUGH DROPS INTO THE AREA LATER TONIGHT AND THE RECENT RAINS...SOME POTENTIAL FOR BR/FG OVER THE WEST END OF THE FCST AREA LATE TONIGHT AND ADDED A PATCHY FOG MENTION FOR PORTIONS OF SOUTHEAST MN/NORTHEAST IA. FAVORED A BLEND OF THE GUIDANCE HIGHS/ LOWS FOR TODAY/TONIGHT. .LONG TERM...(THURSDAY THROUGH TUESDAY) 333 AM CST WED NOV 6 2013 MAIN FORECAST CONCERNS FOR THURSDAY THROUGH FRIDAY NIGHT...MAINLY RAIN CHANCES LATER FRI/FRI NIGHT...TEMPERATURES. MODEL CONSENSUS CONTINUES TO TIGHTEN/IMPROVE FOR THU THRU FRI NIGHT ON THE RATHER PROGRESSIVE FLOW PATTERN THIS PERIOD. HGTS RISE THU WITH SHORTWAVE RIDGING TO PASS EARLY FRI AND THE FLOW TO BECOME NEARLY ZONAL ACROSS THE NORTHERN CONUS BY LATE FRI. EMBEDDED SHORTWAVE QUICKLY TRACKS FROM OR/WA COAST AT 18Z THU TO EAST OF THE AREA BY 12Z SAT. GIVEN THE FAST FLOW THIS PERIOD...MODEL CONSENSUS AS GOOD AS IT WITH THE TROUGH PASSAGE FRI NIGHT IS A BIT SURPRISING. FCST CONFIDENCE REMAINS GOOD FOR THE THU THRU FRI NIGHT PERIOD. SFC HIGH PRESSURE RIDGE AXIS APPROACHES/MOVES ACROSS THE REGION THU INTO FRI MORNING. FOR DRY/QUIET/COOL WEATHER. SFC RIDGE AXIS MOVES ACROSS THE FCST AREA THU NIGHT. IF BOUNDARY LAYER WINDS DECOUPLE AND CAN STAY DECOUPLED THRU THE NIGHT...NOT A GUARANTEE WITH THE SFC RIDGE AXIS MOVING QUICKLY EAST OF THE AREA AND THE PRESSURE GRADIENT STARTING TO TIGHTEN BY 12Z FRI...SOME RADIATIONAL FOG WOULD BE EXPECTED ACROSS THE AREA. LEFT LATE THU NIGHT/EARLY FRI MORNING FOG MENTION OUT OF FCST GRIDS FOR NOW. SFC LOW QUICKLY MOVES INTO WESTERN MN BY 00Z SAT. PRESSURE GRADIENT TIGHTENS OVER MUCH OF MN/IA/WI THRU FRI...FOR SOME BRISK SOUTH WINDS AND WARMING ACROSS MUCH OF THE REGION. MORE MOISTURE/LIFT...MAINLY ABOVE 700MB...AHEAD OF/WITH THIS LOW/SHORTWAVE TO MOVE ACROSS THE REGION LATER FRI/FRI NIGHT. LOW LEVEL WARM ADVECTION SENDS 925-850MB TEMPS ABOVE 0C ACROSS THE AREA FOR FRI AFTERNOON/NIGHT...WITH BULK OF ANY PRECIP CHANCE THESE PERIODS AS -RA...PERHAPS MIXED WITH SOME -SN ACROSS THE FAR NORTH END OF THE FCST AREA TOWARD 12Z SAT. QUESTION IS WILL ANY PRECIP PRODUCED ABOVE 700MB BE ABLE TO FALL THRU THE DRIER SFC-700MB LAYER AND REACH THE GROUND. LEFT PRECIP CHANCES FRI/FRI NIGHT IN THE 20-40 PERCENT CHANCE RANGE...HIGHEST ACROSS THE NORTH END OF THE FCST AREA CLOSER TO THE TRACK OF THE SHORTWAVE AND DEEPER MOISTURE. USED A MODEL CONSENSUS BLEND FOR THE HIGHS/LOWS THIS PERIOD. FOR SATURDAY THROUGH TUESDAY.../DAYS 4 TO 7/... MEDIUM RANGE MODEL RUNS OF 06.00Z IN GOOD AGREEMENT WITH EACH OTHER AND THEIR PREVIOUS RUNS SAT/SAT NIGHT AS TROUGHING SLIDES EAST OF THE REGION SAT AND BROAD RIDGING BUILDS ACROSS THE NORTH-CENTRAL CONUS SAT NIGHT. MODELS THEN DIVERGE WITH TIMING/STRENGTH DETAILS OF A SHORTWAVE TROUGH TO PASS NORTHEAST OF THE REGION LATER SUN INTO MON AND YET ANOTHER NORTHERN STREAM SHORTWAVE TROUGH DROPS INTO THE REGION TUE. RUN-TO-RUN CONSISTENCY LEAVES QUITE A BIT TO BE DESIRED BY MON/TUE. FCST CONFIDENCE ON THE GOOD SIDE SAT...THEN ON THE LOW SIDE FOR EARLY NEXT WEEK. WITH IMPROVING CONSENSUS SAT FOR THE MID LEVEL TROUGH TO BE SLIDING EAST OF THE AREA...ANY LINGERING -RA/-SN CHANCE LOOKS CONFINED TO THE MORNING. DRY/COOL HIGH PRESSURE BUILDS ACROSS THE REGION FOR LATER SAT THRU SUN...UNDER THE BROAD MID LEVEL RIDGING. SHORTWAVE TROUGH TO PASS ACROSS ONT CENTERED ON SUN NIGHT DRIVES A COLD FRONT INTO/ACROSS THE UPPER MIDWEST SUN NIGHT/MON. PLENTY OF DETAIL DIFFERENCES ON THE TIMING OF THIS FRONT THRU THE AREA AND HOW MUCH MOISTURE MAY ACCOMPANY IT. MAY YET NEED A SPRINKLE/FLURRY MENTION MAINLY ALONG/NORTHEAST OF I-94 SUN NIGHT INTO MON BUT AGAIN CONFIDENCE IN THE DETAILS IS LOW BY MON. SOME CONSENSUS THAT THE NEXT SHORTWAVE TROUGH TO DROP TOWARD THE REGION TUE WOULD BE STRONGER WITH MORE OF A LOWER LEVEL THERMO-DYNAMIC FORCING/LIFT RESPONSE AND PERHAPS MORE MOISTURE. A SMALL -RA/-SN CHANCE BY TUE PER A MODEL/ENSEMBLE COMPROMISE REASONABLE FOR NOW. BETTER CONFIDENCE IN THE MON/TUE PERIOD FOR TEMPS TO BE BELOW NORMAL. MODEL/ENSEMBLE CONSENSUS FOR THE SAT THRU TUE HIGHS/LOWS LOOKS WELL TRENDED. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT) ISSUED AT 1138 PM CST TUE NOV 5 2013 SURFACE LOW HAS PROGRESSED RAPIDLY NORTHEAST AND WAS OVER NORTHEAST IOWA LATE THIS EVENING. THE BULK OF THE RAIN CONTINUES OUT AHEAD OF THE LOW WITH THE BACK EDGE OF THE MAIN RAIN SHIELD STARTING TO WORK INTO THE REGION WITH THIS ALREADY COMING THROUGH KRST. EXPECT TO SEE THE RAIN BECOME MORE SCATTERED THROUGH THE NIGHT AS THE FORCING CONTINUES TO MOVE OUT WITH THE SURFACE LOW. BETWEEN 09Z AND 12Z...EXPECT TO SEE THE FORCING REALLY DROP OFF BUT STILL HAVE SOME OMEGA THROUGH THE SATURATED LOW LEVELS AND EXPECT THIS TO PRODUCE DRIZZLE. THE 06.00Z NAM AND RAP CONTINUE TO SUGGEST THE POSSIBILITY OF FREEZING DRIZZLE FOR KRST. HOWEVER... THESE MODELS HAVE BEEN CONSISTENTLY TOO COLD WITH SURFACE TEMPS THROUGH THE EVENING. IN ADDITION...THE COLDER AIR HAS BEEN SLOWLY MOVING SOUTH ACROSS MINNESOTA AND CONCERNED THAT IT MAY NOT ARRIVE BEFORE THE PRECIPITATION ENDS. BASED ON THESE TWO CONCERNS...CANNOT TOTALLY RULE OUT THE POSSIBILITY OF SOME FREEZING DRIZZLE AT KRST BUT AT THIS POINT...FEEL THE PROBABILITY OF THIS OCCURRING IS TOO LOW TO INCLUDE IN THE FORECAST. EXPECT CEILINGS TO REMAIN IFR UNTIL ABOUT 12Z WHEN SOME DRIER LOW LEVEL AIR STARTS TO MOVE ALLOWING THESE TO COME UP TO MVFR AND THEN EVENTUALLY SCATTER OUT BY LATE MORNING TO EARLY AFTERNOON. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...RRS LONG TERM....RRS AVIATION.....04
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1138 PM CST TUE NOV 5 2013 .SHORT TERM...(TONIGHT AND WEDNESDAY) 320 PM CST TUE NOV 5 2013 ATTENTION SQUARELY ON THE SYSTEM MOVING THROUGH TONIGHT AND WEDNESDAY. WIDESPREAD RAIN TONIGHT...AND WITH COOLER AIR ON THE BACK SIDE OF THE SYSTEM...COULD SEE A MIX OR CHANGE TO SNOW... AND MAYBE EVEN FREEZING DRIZZLE. 20Z SURFACE ANALYSIS SHOWED THE LOW PRESSURE CENTER OVER KANSAS... WITH A WARM FRONT REACHING NORTHEAST INTO SOUTHERN WI. WATER VAPOR IMAGERY SHOWED A POTENT JET STREAK MOVING NORTHEAST ACROSS OK/KS. REGIONAL RADAR LOOPS SHOW AN EXPANSIVE AREA OF RAIN REACHING FROM IA AND NORTHERN IL UP INTO SOUTHEAST MN AND SOUTHERN WI. FROM NORTHERN NEBRASKA INTO SD... THE RADAR IMAGERY SHOWED A MORE LAMINAR LOOK...SUGGESTING SNOW. INDEED...LOOKING AT SURFACE OBSERVATIONS OUT THAT WAY...SNOW WAS INDEED FLYING. LATEST MODEL SIMULATIONS ARE IN PRETTY GOOD AGREEMENT WITH THE OVERALL EVOLUTION OF THIS SYSTEM AS IT PROGRESSES RATHER QUICKLY ACROSS THE REGION TONIGHT. THE LOW CENTER SHOULD BE OVER NW MO AROUND 00Z...AND IS EXPECTED TO BE IN EASTERN WI ALREADY BY 12Z. COPIOUS AMOUNTS OF MOISTURE AVAILABLE TO THE SYSTEM WITH PRECIPITABLE WATER OVER 200% OF NORMAL. PRECIPITATION IS A SLAM DUNK OBVIOUSLY...BUT THE MAIN CONCERN WITH THIS SYSTEM IS THE POSSIBILITY OF SNOW OR FREEZING DRIZZLE AS THE COLD AIR ARRIVES ON THE BACK SIDE OF THE SYSTEM. WITH THE TRACK OF THE STORM HEADING OVER SOUTHERN WI OVERNIGHT...THE FORECAST AREA REMAINS MAINLY IN THE WARM SECTOR OF THE STORM. THE ONLY AREA WHERE THIS IS NOT TRUE IS THE FAR NORTHWEST EDGE...FROM ALBERT LEA/KASSON MN...UP THROUGH WABASHA...TO NEAR ABBOTSFORD/MEDFORD WI. ENOUGH COLD AIR COULD FILTER IN LATER THIS EVENING TO ALLOW FOR A MIX WITH OR CHANGE OVER TO SNOW. STILL APPEARS THE HIGHEST THREAT FOR SIGNIFICANT ACCUMULATIONS OF 2-5 INCHES WILL LIE JUST BEYOND THE FORECAST AREA...BUT SOME SPOTS ALONG THE AFOREMENTIONED LINE COULD SEE SOME BRIEF ACCUMULATIONS UP AROUND AN INCH OR SO ON GRASSY AREAS AND OTHER EXPOSED SURFACES. THE MAIN UPWARD MOTION AND FORCING SHIFT EAST OF THE AREA DURING THE OVERNIGHT HOURS. THIS ALLOWS THE FRONT TO MOVE BACK SOUTHEAST AS A COLD FRONT...ALLOWING THE COLD AIR TO INVADE. BUT LOOKING AT THE MODEL SOUNDINGS...THIS COLD AIR ARRIVES JUST AS THE UPPER LEVEL CLOUD AND SUPPLY OF ICE FOR SEEDING THE LOW LEVELS MOVES AWAY. IF THE ICE CAN LINGER LONGER...WE MAY SEE A BIT MORE SNOW ACROSS THE REGION OVERNIGHT. BUT EVEN IF WE DO...IT LIKELY WILL NOT ADD UP TO MUCH. AND IF THE ICE INDEED DOES DEPART...SOUNDINGS SUPPORT DRIZZLE TO CONTINUE FOR SEVERAL HOURS. COULD SOME OF THIS MANIFEST AS FREEZING DRIZZLE? CERTAINLY IT COULD...WITH THE HIGHEST LIKELIHOOD OVER PARTS OF SOUTHEAST MN WEST OF ROCHESTER. FURTHER EAST...THE RAIN WILL TAPER OFF AND BECOME LIGHT...TRANSITIONING TO DRIZZLE AS WELL. THE ENTIRE SYSTEM EJECTS QUICKLY EASTWARD WEDNESDAY MORNING...SO THAT BY MID-DAY THE PRECIPITATION SHOULD BE ENDED. SKIES WILL THEN CLEAR FROM WEST TO EAST ACROSS THE REGION...WITH MAINLY CLEAR SKIES BY SUNSET. DESPITE THE CLEARING AND RESULTING SUNSHINE... THE ARRIVAL OF COOLER AIR WILL OFFSET THE WARMING EFFECTS OF THE SUN...SO NOT MUCH WARMING IS ANTICIPATED. .LONG TERM...(WEDNESDAY NIGHT THROUGH NEXT TUESDAY) 320 PM CST TUE NOV 5 2013 A LONG WAVE TROUGH OVER THE AREA WILL SHIFT TO THE EAST ON THURSDAY...WITH SURFACE HIGH PRESSURE BUILDING IN. THERE IS SOME CONCERN WITH CHANNELED VORTICITY DROPPING INTO THE BACK SIDE OF THE TROUGH COULD BRING MORE CLOUDINESS OVER WI THURSDAY...WITH THE OUTSIDE CHANCE OF A SPRINKLE GIVEN THE STEEP LAPSE RATES AND COOL AIRMASS IN PLACE. BUT THE ATMOSPHERE LOOKS PRETTY MOISTURE STARVED DURING THAT TIMEFRAME...SO WILL NOT INCLUDE ANY MENTION YET. THE NEXT SHORT WAVE TROUGH COMES ZIPPING THROUGH THE NORTHERN CONUS LATE FRIDAY INTO SATURDAY...FLATTENING THE UPPER RIDGE. MODELS HAVE BEEN STRUGGLING WITH THE LOCATION AND TIMING OF THIS FEATURE FOR SEVERAL DAYS NOW...AND TODAY NO DIFFERENT. AS THE MAIN SURFACE LOW CENTER PASSES WELL NORTH OF THE LOCAL AREA...OUR CHANCE FOR ANY PRECIPITATION WILL COME WITH THE WARM ADVECTION AHEAD OF THE LEADING WARM FRONT AS IT CROSSES FRIDAY NIGHT INTO EARLY SATURDAY. THE TRAILING COLD FRONT LOOKS TO MOVE THROUGH DURING THE DAY ON SATURDAY...BUT WITH NO FORCING ALONG IT...DOES NOT APPEAR TO BE A THREAT FOR ANY PRECIPITATION. MODELS REALLY DIVERGE WITH RESPECT TO ENERGY ROTATING AROUND A CANADIAN TROUGH BY LATE SUNDAY...ALTHOUGH THE LATEST 05.12Z ECMWF HAS COME MORE INTO LINE WITH THE GFS. DOES NOT APPEAR THERE WILL BE MUCH OF A PRECIPITATION THREAT...BUT A REINFORCING SHOT OF COOL AIR LOOKS TO INVADE FOR EARLY NEXT WEEK...POTENTIALLY SENDING TEMPERATURES ON A DOWNWARD TREND. WAS CONSERVATIVE ON THIS COOLING TREND AT THIS POINT WITH THE UNCERTAINTY. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT) ISSUED AT 1138 PM CST TUE NOV 5 2013 SURFACE LOW HAS PROGRESSED RAPIDLY NORTHEAST AND WAS OVER NORTHEAST IOWA LATE THIS EVENING. THE BULK OF THE RAIN CONTINUES OUT AHEAD OF THE LOW WITH THE BACK EDGE OF THE MAIN RAIN SHIELD STARTING TO WORK INTO THE REGION WITH THIS ALREADY COMING THROUGH KRST. EXPECT TO SEE THE RAIN BECOME MORE SCATTERED THROUGH THE NIGHT AS THE FORCING CONTINUES TO MOVE OUT WITH THE SURFACE LOW. BETWEEN 09Z AND 12Z...EXPECT TO SEE THE FORCING REALLY DROP OFF BUT STILL HAVE SOME OMEGA THROUGH THE SATURATED LOW LEVELS AND EXPECT THIS TO PRODUCE DRIZZLE. THE 06.00Z NAM AND RAP CONTINUE TO SUGGEST THE POSSIBILITY OF FREEZING DRIZZLE FOR KRST. HOWEVER...THESE MODELS HAVE BEEN CONSISENTLY TOO COLD WITH SURFACE TEMPS THROUGH THE EVENING. IN ADDITION...THE COLDER AIR HAS BEEN SLOWLY MOVING SOUTH ACROSS MINNESOTA AND CONCERNED THAT IT MAY NOT ARRIVE BEFORE THE PRECIPITATION ENDS. BASED ON THESE TWO CONCERNS...CANNOT TOTALLY RULE OUT THE POSSIBILITY OF SOME FREEZING DRIZZLE AT KRST BUT AT THIS POINT...FEEL THE PROBABILITY OF THIS OCCURRING IS TOO LOW TO INCLUDE IN THE FORECAST. EXPECT CEILINGS TO REMAIN IFR UNTIL ABOUT 12Z WHEN SOME DRIER LOW LEVEL AIR STARTS TO MOVE ALLOWING THESE TO COME UP TO MVFR AND THEN EVENTUALLY SCATTER OUT BY LATE MORNING TO EARLY AFTERNOON. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...MW LONG TERM...MW AVIATION...04
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
940 AM CST WED NOV 6 2013 .DISCUSSION... 318 AM CST PRIMARY FORECAST CHALLENGE THIS MORNING IS WRAPPING UP AND ESCORTING THE CURRENT STORM SYSTEM OUT OF THE AREA. WAVES OF RAIN ARE SPREADING NORTHEAST FROM MISSOURI INTO THE AREA...WITH SOME EMBEDDED POCKETS OF HEAVIER RAIN...ESPECIALLY UPSTREAM. FAIRLY WIDESPREAD RAIN WILL CONTINUE THROUGH THE EARLY MORNING HOURS BEFORE ENDING FROM WEST TO EAST...ENDING FIRST IN WESTERN CWA TOWARD MID MORNING...INTO CHGO METRO AROUND MIDDAY AND NW INDY EARLY/MID AFTERNOON. STILL THINKING GENERALLY A HALF INCH TO AN INCH OF RAIN WILL BE COMMON WITH LIGHTEST AMOUNTS OVER NC IL AND PROBABLY SOME EMBEDDED AREAS PICKING UP OVER AN INCH WHERE THE HEAVIEST ELEMENTS LINE UP. WILL NEED TO KEEP AN EYE OUT FOR SOME POTENTIAL PONDING OF WATER TYPE ISSUES IN THE URBANIZED POOR DRAINAGE AREAS FOR THIS MORNING`S RUSH HOUR...BUT OVERALL FLOOD THREAT APPEARS MINIMAL. ENDING OF THE RAIN SHOULD BE FAIRLY COINCIDENT WITH THE PASSAGE OF A FAIRLY STRONG COLD FRONT THIS AFTERNOON. GUSTY NORTHWEST WIND SHIFT SHOULD SEND TEMPS TUMBLING QUICKLY INTO THE 40S WITH THE FROPA AND HAVE SHARPENED THERMAL GRADIENT IN THE GRIDS...THOUGH LIKELY NOT ENOUGH WITH PROBABLY A GOOD 10F DROP WITHIN AN HOUR OF FROPA. GUIDANCE CONTINUES TO STRONGLY SUGGEST A RAPID CLEARING AFTER THE FRONT AND WHILE ITS NOT TYPICAL THIS TIME OF YEAR TO NOT HAVE POST FRONTAL STRATUS...HARD TO DISPUTE SUCH STRONG MODEL AGREEMENT SO HAVE SHARPENED UP THE CLEARING LINE AND SPED IT UP AS WELL. WINDS DIMINISH TONIGHT AND ASSUMING WE CLEAR OUT AS ADVERTISED IT SHOULD BE A FAIRLY COLD NIGHT. SIGNIFICANT ENOUGH DRY AIR ADVECTION SHOULD TAKE PLACE TO LIMIT THE THREAT OF WIDESPREAD FOG...BUT SOME SPOTTY VERY SHALLOW GROUND FOG IS CERTAINLY POSSIBLE IN THE FAVORED LOW SPOTS. PRETTY LAME WEATHER PATTERN SETTING UP LATE IN THE WEEK THROUGH EARLY NEXT WEEK WITH WEST NORTHWEST FLOW ALOFT. MODELS DO BRING A STRONG CLIPPER THROUGH THE UPPER GREAT LAKES LATE FRIDAY/EARLY SATURDAY...BUT THE TRACK OF THE SYSTEM LOOKS TO BE FAR ENOUGH NORTH THAT THE BETTER FORCING SHOULD MISS OUR CWA AND WITH SYSTEM HAVING TO RELY ON SQUEEZING OUT WHAT LITTLE MOISTURE THERE IS ALREADY PRESENT...THINKING OUR PRECIP CHANCES WILL BE VERY SLIM. INCREASING SOUTH WINDS FRIDAY NIGHT SHOULD RESULT IN FAIRLY MILD NIGHT WITH NEAR STEADY TEMPS...OR POSSIBLY AN EVENING LOW WITH SLOWLY RISING TEMPS. THE MILD START TO THE DAY SHOULD ALLOW FOR A SOMEWHAT MILDER DAY SATURDAY BEFORE NEXT COLD FRONT COOLS TEMPS DOWN A BIT SUNDAY. HUGE MODEL DIFFERENCES EARLY NEXT WEEK MEANS LOW CONFIDENCE AND LEAVES ME GUN SHY TO MAKE ANY CHANGES TO THE BLENDED MODEL CONCOCTION THAT WE USE TO INITIALIZE THE FORECAST. IF ECMWF IS RIGHT WE WOULD BE ABOVE AVERAGE TEMP-WISE MONDAY WHILE GFS HAS US SOLIDLY BELOW AVERAGE...SO STAY TUNED! IZZI && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 16Z... * TIMING OF COLD FRONTAL PASSAGE AND WIND SHIFT BETWEEN 17 AND 1730 UTC. * TIMING LIFTING OF IFR/LOW MVFR CIGS THIS AFTERNOON. TRS/KB //DISCUSSION...UPDATED 12Z... AT 11Z A DEEP UPPER TROUGH WAS FROM EASTERN MANITOBA SSW OVER THE EASTERN DAKOTAS AND THEN SW BACK TO OVER THE SOUTHERN HIGH PLAINS. WITHIN THE FAST SW FLOW OUT AHEAD OF THE TROUGH WERE MULTIPLE SHORT WAVES LIFTING TOWARDS AND ACROSS THE MID MS VALLEY...ONE OF WHICH HAD GENERATED SOME CONVECTIVE CELLS AND HEAVY DOWNPOURS ACROSS THE LOCAL AREA. THIS HEAVIER RAINFALL IS EXPECTED TO BE MOVING NE OUT THE AREA WITH THE DISTURBANCE MOVING FROM OVERHEAD TO THE NE OF THE AREA. THIS LEAVES A SATURATED COLUMN OVER THE AREA FOR THE MID AND LATE MORNING SO EXPECT CIGS TO CONTINUE ON THE LOW SIDE WHILE -RA/-SHRA HANG AROUND AS THE LEFT EXIT REGION RIGHT ENTRANCE REGION OF UPPER JET MAXIMA MOVE OVER THE THE LOCAL AREA THIS MORNING. TIMING OF CFP AT AROUND 18Z STILL LOOKS ON TRACK WITH HIGHER RESOLUTION OF RAP OUTPUT MAINTAINING THE SHARPER WIND SHIFT THAT IS CURRENTLY OBSERVED TO THE W AS OPPOSED TO THE MORE GRADUAL VEERING DEPICTED BY THE COARSER MODELS. WHILE TREND UPSTREAM DURING THE LATE EVENING AND OVERNIGHT HAD BEEN S WINDS QUICKLY SHIFTING TO OUT OF THE N WITH THE FROPA BUT THIS HAS BECOME MORE OF SSW TO NNW WSHFT EARLY THIS MORNING. WITH THE SURFACE LOW CONTINUING TO MOVE OFF TO THE NE TODAY FELL THAT THIS WILL CONTINUE TO TRANSITION TO SW TO NW WSHFT BY THE TIME THE COLD FRONT MOVES INTO THE LOCAL AREA. WHILE THERE HAD BEEN A FAIRLY STRONG PRESSURE RISE CENTER FROM N CENTRAL AND SW IA TO EASTERN KS DURING THE OVERNIGHT THIS PRESSURE RISE CENTER HAS SHIFTED TO SW MO BY PREDAWN. WHILE DO EXPECT THE NW WINDS BEHIND THE FRONT TO BE MODERATELY GUSTY FEEL THAT THEY SHOULD GENERALLY STAY IN THE 20-25 KT RANGE. WITH SOME DECOUPLING OF THE SURFACE TONIGHT UNDER MOSTLY CLEAR TO CLEAR SKIES WINDS SHOULD SLACKEN TO 10 KT OR LESS DURING THE OVERNIGHT...AND DIURNALLY DUE TO THE DECOUPLING...AS WELL AS DUE TO A LARGE ANTICYCLONE BUILDING FROM THE ROCKIES TO THE PLAINS DURING TODAY AND TONIGHT...BUT ALSO AHEAD OF A SURFACE TROUGH/SECONDARY COLD FRONT ASSOCIATED WITH ANOTHER SHORT WAVE PROGGED TO BE DROPPING ACROSS THE DAKOTAS TO THE UPPER MS AND MID MO VALLEYS OVERNIGHT. TRS //ORD AND MDW CONFIDENCE...UPDATED 16Z... * HIGH ON FRONTAL PASSAGE TIMING WITH WIND SHIFT AT 1700 TO 1730 UTC. * MEDIUM ON TIMING OF CIG IMPROVEMENTS THIS AFTERNOON. * MEDIUM TO HIGH WITH WINDS. TRS/KB //OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z... THURSDAY NIGHT...VFR...NO SIG WX. FRIDAY...VFR...NO SIG WX. SATURDAY...VFR...MODERATE SW WINDS. SUNDAY...VFR...NO SIG WX. MONDAY...VFR...NO SIG WX. TUESDAY...VFR. SLIGHT CHANCE SHOWERS. TRS && .MARINE... 411 AM CST WINDS WILL GRADUALLY DIMINISH EARLY THIS MORNING BUT STILL BE GUSTING TO 35 KT ON CENTRAL AND ESPECIALLY SOUTHERN LAKE MI UNTIL MID MORNING AS LOW PRESSURE LIFTS NORTHEAST FROM WI INTO ONTARIO BY MIDDAY. AS IT DOES IT WILL SWEEP A COLD FRONT ACROSS LAKE MICHIGAN SHIFTING WINDS TO OUT OF THE NORTHWEST. THERE WILL BE A SHORT LULL IN THE WINDS AS THE COLD FRONT PASSES. THEY WILL WILL INCREASE AGAIN POST FRONTAL THOUGH ARE EXPECTED TO REMAIN BELOW GALE FORCE THIS AFTERNOON AND TONIGHT AS HIGH PRESSURE BUILDING SOUTHEASTWARD ACROSS THE ROCKIES AND INTO THE PLAINS MAINTAINS A FAIRLY STRONG PRESSURE GRADIENT ACROSS THE REGION DESPITE THE LOW MOVING NE TO THE CENTRAL QUEBEC BY EVENING. WINDS DIMINISH AND BACK TO SOUTHWEST DURING FRIDAY BEFORE STRENGTHENING AGAIN LATE FRIDAY AS ANTHER LOW DEEPENS AS IT MOVES FROM SOUTHERN ALBERTA EAST TO WESTERN ONTARIO. GALE FORCE WINDS ARE A POSSIBILITY LATER FRIDAY NIGHT INTO SATURDAY AS THE LOW MOVES ACROSS S CENTRAL CANADA. AS THE LOW CONTINUES EASTWARD ACROSS ONTARIO SATURDAY A TRAILING COLD FRONT WILL MOVE INTO THE UPPER GREAT LAKES BRINGING ANOTHER WIND SHIFT TO OUT OF THE NORTHWEST. && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...GALE WARNING...LMZ080-LMZ675-LMZ777-LMZ779-LMZ872-LMZ874-LMZ876- LMZ878 UNTIL NOON WEDNESDAY. SMALL CRAFT ADVISORY...ILLINOIS NEARSHORE WATERS UNTIL 10 PM WEDNESDAY. SMALL CRAFT ADVISORY...INDIANA NEARSHORE WATERS UNTIL 4 PM THURSDAY. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
810 AM CST WED NOV 6 2013 .DISCUSSION... 318 AM CST PRIMARY FORECAST CHALLENGE THIS MORNING IS WRAPPING UP AND ESCORTING THE CURRENT STORM SYSTEM OUT OF THE AREA. WAVES OF RAIN ARE SPREADING NORTHEAST FROM MISSOURI INTO THE AREA...WITH SOME EMBEDDED POCKETS OF HEAVIER RAIN...ESPECIALLY UPSTREAM. FAIRLY WIDESPREAD RAIN WILL CONTINUE THROUGH THE EARLY MORNING HOURS BEFORE ENDING FROM WEST TO EAST...ENDING FIRST IN WESTERN CWA TOWARD MID MORNING...INTO CHGO METRO AROUND MIDDAY AND NW INDY EARLY/MID AFTERNOON. STILL THINKING GENERALLY A HALF INCH TO AN INCH OF RAIN WILL BE COMMON WITH LIGHTEST AMOUNTS OVER NC IL AND PROBABLY SOME EMBEDDED AREAS PICKING UP OVER AN INCH WHERE THE HEAVIEST ELEMENTS LINE UP. WILL NEED TO KEEP AN EYE OUT FOR SOME POTENTIAL PONDING OF WATER TYPE ISSUES IN THE URBANIZED POOR DRAINAGE AREAS FOR THIS MORNING`S RUSH HOUR...BUT OVERALL FLOOD THREAT APPEARS MINIMAL. ENDING OF THE RAIN SHOULD BE FAIRLY COINCIDENT WITH THE PASSAGE OF A FAIRLY STRONG COLD FRONT THIS AFTERNOON. GUSTY NORTHWEST WIND SHIFT SHOULD SEND TEMPS TUMBLING QUICKLY INTO THE 40S WITH THE FROPA AND HAVE SHARPENED THERMAL GRADIENT IN THE GRIDS...THOUGH LIKELY NOT ENOUGH WITH PROBABLY A GOOD 10F DROP WITHIN AN HOUR OF FROPA. GUIDANCE CONTINUES TO STRONGLY SUGGEST A RAPID CLEARING AFTER THE FRONT AND WHILE ITS NOT TYPICAL THIS TIME OF YEAR TO NOT HAVE POST FRONTAL STRATUS...HARD TO DISPUTE SUCH STRONG MODEL AGREEMENT SO HAVE SHARPENED UP THE CLEARING LINE AND SPED IT UP AS WELL. WINDS DIMINISH TONIGHT AND ASSUMING WE CLEAR OUT AS ADVERTISED IT SHOULD BE A FAIRLY COLD NIGHT. SIGNIFICANT ENOUGH DRY AIR ADVECTION SHOULD TAKE PLACE TO LIMIT THE THREAT OF WIDESPREAD FOG...BUT SOME SPOTTY VERY SHALLOW GROUND FOG IS CERTAINLY POSSIBLE IN THE FAVORED LOW SPOTS. PRETTY LAME WEATHER PATTERN SETTING UP LATE IN THE WEEK THROUGH EARLY NEXT WEEK WITH WEST NORTHWEST FLOW ALOFT. MODELS DO BRING A STRONG CLIPPER THROUGH THE UPPER GREAT LAKES LATE FRIDAY/EARLY SATURDAY...BUT THE TRACK OF THE SYSTEM LOOKS TO BE FAR ENOUGH NORTH THAT THE BETTER FORCING SHOULD MISS OUR CWA AND WITH SYSTEM HAVING TO RELY ON SQUEEZING OUT WHAT LITTLE MOISTURE THERE IS ALREADY PRESENT...THINKING OUR PRECIP CHANCES WILL BE VERY SLIM. INCREASING SOUTH WINDS FRIDAY NIGHT SHOULD RESULT IN FAIRLY MILD NIGHT WITH NEAR STEADY TEMPS...OR POSSIBLY AN EVENING LOW WITH SLOWLY RISING TEMPS. THE MILD START TO THE DAY SHOULD ALLOW FOR A SOMEWHAT MILDER DAY SATURDAY BEFORE NEXT COLD FRONT COOLS TEMPS DOWN A BIT SUNDAY. HUGE MODEL DIFFERENCES EARLY NEXT WEEK MEANS LOW CONFIDENCE AND LEAVES ME GUN SHY TO MAKE ANY CHANGES TO THE BLENDED MODEL CONCOCTION THAT WE USE TO INITIALIZE THE FORECAST. IF ECMWF IS RIGHT WE WOULD BE ABOVE AVERAGE TEMP-WISE MONDAY WHILE GFS HAS US SOLIDLY BELOW AVERAGE...SO STAY TUNED! IZZI && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 14Z... * TIMING OF COLD FRONTAL PASSAGE AND WIND SHIFT AROUND MIDDAY. * WIND SPEED AND GUSTS PRE AND POST FRONTAL. * TIMING LIFTING OF IFR/LOW MVFR CIGS THIS AFTERNOON. TRS/KB //DISCUSSION...UPDATED 12Z... AT 11Z A DEEP UPPER TROUGH WAS FROM EASTERN MANITOBA SSW OVER THE EASTERN DAKOTAS AND THEN SW BACK TO OVER THE SOUTHERN HIGH PLAINS. WITHIN THE FAST SW FLOW OUT AHEAD OF THE TROUGH WERE MULTIPLE SHORT WAVES LIFTING TOWARDS AND ACROSS THE MID MS VALLEY...ONE OF WHICH HAD GENERATED SOME CONVECTIVE CELLS AND HEAVY DOWNPOURS ACROSS THE LOCAL AREA. THIS HEAVIER RAINFALL IS EXPECTED TO BE MOVING NE OUT THE AREA WITH THE DISTURBANCE MOVING FROM OVERHEAD TO THE NE OF THE AREA. THIS LEAVES A SATURATED COLUMN OVER THE AREA FOR THE MID AND LATE MORNING SO EXPECT CIGS TO CONTINUE ON THE LOW SIDE WHILE -RA/-SHRA HANG AROUND AS THE LEFT EXIT REGION RIGHT ENTRANCE REGION OF UPPER JET MAXIMA MOVE OVER THE THE LOCAL AREA THIS MORNING. TIMING OF CFP AT AROUND 18Z STILL LOOKS ON TRACK WITH HIGHER RESOLUTION OF RAP OUTPUT MAINTAINING THE SHARPER WIND SHIFT THAT IS CURRENTLY OBSERVED TO THE W AS OPPOSED TO THE MORE GRADUAL VEERING DEPICTED BY THE COARSER MODELS. WHILE TREND UPSTREAM DURING THE LATE EVENING AND OVERNIGHT HAD BEEN S WINDS QUICKLY SHIFTING TO OUT OF THE N WITH THE FROPA BUT THIS HAS BECOME MORE OF SSW TO NNW WSHFT EARLY THIS MORNING. WITH THE SURFACE LOW CONTINUING TO MOVE OFF TO THE NE TODAY FELL THAT THIS WILL CONTINUE TO TRANSITION TO SW TO NW WSHFT BY THE TIME THE COLD FRONT MOVES INTO THE LOCAL AREA. WHILE THERE HAD BEEN A FAIRLY STRONG PRESSURE RISE CENTER FROM N CENTRAL AND SW IA TO EASTERN KS DURING THE OVERNIGHT THIS PRESSURE RISE CENTER HAS SHIFTED TO SW MO BY PREDAWN. WHILE DO EXPECT THE NW WINDS BEHIND THE FRONT TO BE MODERATELY GUSTY FEEL THAT THEY SHOULD GENERALLY STAY IN THE 20-25 KT RANGE. WITH SOME DECOUPLING OF THE SURFACE TONIGHT UNDER MOSTLY CLEAR TO CLEAR SKIES WINDS SHOULD SLACKEN TO 10 KT OR LESS DURING THE OVERNIGHT...AND DIURNALLY DUE TO THE DECOUPLING...AS WELL AS DUE TO A LARGE ANTICYCLONE BUILDING FROM THE ROCKIES TO THE PLAINS DURING TODAY AND TONIGHT...BUT ALSO AHEAD OF A SURFACE TROUGH/SECONDARY COLD FRONT ASSOCIATED WITH ANOTHER SHORT WAVE PROGGED TO BE DROPPING ACROSS THE DAKOTAS TO THE UPPER MS AND MID MO VALLEYS OVERNIGHT. TRS //ORD AND MDW CONFIDENCE...UPDATED 14Z... * HIGH ON FRONTAL PASSAGE TIMING WITH WIND SHIFT AT 18Z +/- 1HR. * MEDIUM ON TIMING OF CIG IMPROVEMENTS THIS AFTERNOON. * MEDIUM TO HIGH WITH WINDS. TRS/KB //OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z... THURSDAY NIGHT...VFR...NO SIG WX. FRIDAY...VFR...NO SIG WX. SATURDAY...VFR...MODERATE SW WINDS. SUNDAY...VFR...NO SIG WX. MONDAY...VFR...NO SIG WX. TUESDAY...VFR. SLIGHT CHANCE SHOWERS. TRS && .MARINE... 411 AM CST WINDS WILL GRADUALLY DIMINISH EARLY THIS MORNING BUT STILL BE GUSTING TO 35 KT ON CENTRAL AND ESPECIALLY SOUTHERN LAKE MI UNTIL MID MORNING AS LOW PRESSURE LIFTS NORTHEAST FROM WI INTO ONTARIO BY MIDDAY. AS IT DOES IT WILL SWEEP A COLD FRONT ACROSS LAKE MICHIGAN SHIFTING WINDS TO OUT OF THE NORTHWEST. THERE WILL BE A SHORT LULL IN THE WINDS AS THE COLD FRONT PASSES. THEY WILL WILL INCREASE AGAIN POST FRONTAL THOUGH ARE EXPECTED TO REMAIN BELOW GALE FORCE THIS AFTERNOON AND TONIGHT AS HIGH PRESSURE BUILDING SOUTHEASTWARD ACROSS THE ROCKIES AND INTO THE PLAINS MAINTAINS A FAIRLY STRONG PRESSURE GRADIENT ACROSS THE REGION DESPITE THE LOW MOVING NE TO THE CENTRAL QUEBEC BY EVENING. WINDS DIMINISH AND BACK TO SOUTHWEST DURING FRIDAY BEFORE STRENGTHENING AGAIN LATE FRIDAY AS ANTHER LOW DEEPENS AS IT MOVES FROM SOUTHERN ALBERTA EAST TO WESTERN ONTARIO. GALE FORCE WINDS ARE A POSSIBILITY LATER FRIDAY NIGHT INTO SATURDAY AS THE LOW MOVES ACROSS S CENTRAL CANADA. AS THE LOW CONTINUES EASTWARD ACROSS ONTARIO SATURDAY A TRAILING COLD FRONT WILL MOVE INTO THE UPPER GREAT LAKES BRINGING ANOTHER WIND SHIFT TO OUT OF THE NORTHWEST. && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...GALE WARNING...LMZ567-LMZ669-LMZ671-LMZ673-LMZ868-LMZ870 UNTIL 9 AM WEDNESDAY. GALE WARNING...LMZ080-LMZ675-LMZ777-LMZ779-LMZ872-LMZ874-LMZ876- LMZ878 UNTIL NOON WEDNESDAY. SMALL CRAFT ADVISORY...ILLINOIS NEARSHORE WATERS UNTIL 10 PM WEDNESDAY. SMALL CRAFT ADVISORY...INDIANA NEARSHORE WATERS UNTIL 4 PM THURSDAY. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
655 AM CST WED NOV 6 2013 .DISCUSSION... 318 AM CST PRIMARY FORECAST CHALLENGE THIS MORNING IS WRAPPING UP AND ESCORTING THE CURRENT STORM SYSTEM OUT OF THE AREA. WAVES OF RAIN ARE SPREADING NORTHEAST FROM MISSOURI INTO THE AREA...WITH SOME EMBEDDED POCKETS OF HEAVIER RAIN...ESPECIALLY UPSTREAM. FAIRLY WIDESPREAD RAIN WILL CONTINUE THROUGH THE EARLY MORNING HOURS BEFORE ENDING FROM WEST TO EAST...ENDING FIRST IN WESTERN CWA TOWARD MID MORNING...INTO CHGO METRO AROUND MIDDAY AND NW INDY EARLY/MID AFTERNOON. STILL THINKING GENERALLY A HALF INCH TO AN INCH OF RAIN WILL BE COMMON WITH LIGHTEST AMOUNTS OVER NC IL AND PROBABLY SOME EMBEDDED AREAS PICKING UP OVER AN INCH WHERE THE HEAVIEST ELEMENTS LINE UP. WILL NEED TO KEEP AN EYE OUT FOR SOME POTENTIAL PONDING OF WATER TYPE ISSUES IN THE URBANIZED POOR DRAINAGE AREAS FOR THIS MORNING`S RUSH HOUR...BUT OVERALL FLOOD THREAT APPEARS MINIMAL. ENDING OF THE RAIN SHOULD BE FAIRLY COINCIDENT WITH THE PASSAGE OF A FAIRLY STRONG COLD FRONT THIS AFTERNOON. GUSTY NORTHWEST WIND SHIFT SHOULD SEND TEMPS TUMBLING QUICKLY INTO THE 40S WITH THE FROPA AND HAVE SHARPENED THERMAL GRADIENT IN THE GRIDS...THOUGH LIKELY NOT ENOUGH WITH PROBABLY A GOOD 10F DROP WITHIN AN HOUR OF FROPA. GUIDANCE CONTINUES TO STRONGLY SUGGEST A RAPID CLEARING AFTER THE FRONT AND WHILE ITS NOT TYPICAL THIS TIME OF YEAR TO NOT HAVE POST FRONTAL STRATUS...HARD TO DISPUTE SUCH STRONG MODEL AGREEMENT SO HAVE SHARPENED UP THE CLEARING LINE AND SPED IT UP AS WELL. WINDS DIMINISH TONIGHT AND ASSUMING WE CLEAR OUT AS ADVERTISED IT SHOULD BE A FAIRLY COLD NIGHT. SIGNIFICANT ENOUGH DRY AIR ADVECTION SHOULD TAKE PLACE TO LIMIT THE THREAT OF WIDESPREAD FOG...BUT SOME SPOTTY VERY SHALLOW GROUND FOG IS CERTAINLY POSSIBLE IN THE FAVORED LOW SPOTS. PRETTY LAME WEATHER PATTERN SETTING UP LATE IN THE WEEK THROUGH EARLY NEXT WEEK WITH WEST NORTHWEST FLOW ALOFT. MODELS DO BRING A STRONG CLIPPER THROUGH THE UPPER GREAT LAKES LATE FRIDAY/EARLY SATURDAY...BUT THE TRACK OF THE SYSTEM LOOKS TO BE FAR ENOUGH NORTH THAT THE BETTER FORCING SHOULD MISS OUR CWA AND WITH SYSTEM HAVING TO RELY ON SQUEEZING OUT WHAT LITTLE MOISTURE THERE IS ALREADY PRESENT...THINKING OUR PRECIP CHANCES WILL BE VERY SLIM. INCREASING SOUTH WINDS FRIDAY NIGHT SHOULD RESULT IN FAIRLY MILD NIGHT WITH NEAR STEADY TEMPS...OR POSSIBLY AN EVENING LOW WITH SLOWLY RISING TEMPS. THE MILD START TO THE DAY SHOULD ALLOW FOR A SOMEWHAT MILDER DAY SATURDAY BEFORE NEXT COLD FRONT COOLS TEMPS DOWN A BIT SUNDAY. HUGE MODEL DIFFERENCES EARLY NEXT WEEK MEANS LOW CONFIDENCE AND LEAVES ME GUN SHY TO MAKE ANY CHANGES TO THE BLENDED MODEL CONCOCTION THAT WE USE TO INITIALIZE THE FORECAST. IF ECMWF IS RIGHT WE WOULD BE ABOVE AVERAGE TEMP-WISE MONDAY WHILE GFS HAS US SOLIDLY BELOW AVERAGE...SO STAY TUNED! IZZI && //ORD AND MDW CONCERNS...UPDATED 12Z... * LLWS INTO EARLY THIS MORNING. * ENDING OF MODERATE TO OCNLY HEAVY RA WITHIN THE NEXT HR OR TWO. * TIMING COLD FRONTAL PASSAGE. * WIND SPEED AND GUSTS PRE AND POST FRONTAL. * LIFTING OF IFR CIGS TO MVFR FOLLOWING CFP AND EVENTUALLY TO VFR LATER THIS AFTERNOON. TRS //DISCUSSION...UPDATED 12Z... AT 11Z A DEEP UPPER TROUGH WAS FROM EASTERN MANITOBA SSW OVER THE EASTERN DAKOTAS AND THEN SW BACK TO OVER THE SOUTHERN HIGH PLAINS. WITHIN THE FAST SW FLOW OUT AHEAD OF THE TROUGH WERE MULTIPLE SHORT WAVES LIFTING TOWARDS AND ACROSS THE MID MS VALLEY...ONE OF WHICH HAD GENERATED SOME CONVECTIVE CELLS AND HEAVY DOWNPOURS ACROSS THE LOCAL AREA. THIS HEAVIER RAINFALL IS EXPECTED TO BE MOVING NE OUT THE AREA WITH THE DISTURBANCE MOVING FROM OVERHEAD TO THE NE OF THE AREA. THIS LEAVES A SATURATED COLUMN OVER THE AREA FOR THE MID AND LATE MORNING SO EXPECT CIGS TO CONTINUE ON THE LOW SIDE WHILE -RA/-SHRA HANG AROUND AS THE LEFT EXIT REGION RIGHT ENTRANCE REGION OF UPPER JET MAXIMA MOVE OVER THE THE LOCAL AREA THIS MORNING. TIMING OF CFP AT AROUND 18Z STILL LOOKS ON TRACK WITH HIGHER RESOLUTION OF RAP OUTPUT MAINTAINING THE SHARPER WIND SHIFT THAT IS CURRENTLY OBSERVED TO THE W AS OPPOSED TO THE MORE GRADUAL VEERING DEPICTED BY THE COARSER MODELS. WHILE TREND UPSTREAM DURING THE LATE EVENING AND OVERNIGHT HAD BEEN S WINDS QUICKLY SHIFTING TO OUT OF THE N WITH THE FROPA BUT THIS HAS BECOME MORE OF SSW TO NNW WSHFT EARLY THIS MORNING. WITH THE SURFACE LOW CONTINUING TO MOVE OFF TO THE NE TODAY FELL THAT THIS WILL CONTINUE TO TRANSITION TO SW TO NW WSHFT BY THE TIME THE COLD FRONT MOVES INTO THE LOCAL AREA. WHILE THERE HAD BEEN A FAIRLY STRONG PRESSURE RISE CENTER FROM N CENTRAL AND SW IA TO EASTERN KS DURING THE OVERNIGHT THIS PRESSURE RISE CENTER HAS SHIFTED TO SW MO BY PREDAWN. WHILE DO EXPECT THE NW WINDS BEHIND THE FRONT TO BE MODERATELY GUSTY FEEL THAT THEY SHOULD GENERALLY STAY IN THE 20-25 KT RANGE. WITH SOME DECOUPLING OF THE SURFACE TONIGHT UNDER MOSTLY CLEAR TO CLEAR SKIES WINDS SHOULD SLACKEN TO 10 KT OR LESS DURING THE OVERNIGHT...AND DIURNALLY DUE TO THE DECOUPLING...AS WELL AS DUE TO A LARGE ANTICYCLONE BUILDING FROM THE ROCKIES TO THE PLAINS DURING TODAY AND TONIGHT...BUT ALSO AHEAD OF A SURFACE TROUGH/SECONDARY COLD FRONT ASSOCIATED WITH ANOTHER SHORT WAVE PROGGED TO BE DROPPING ACROSS THE DAKOTAS TO THE UPPER MS AND MID MO VALLEYS OVERNIGHT. TRS //ORD AND MDW CONFIDENCE...UPDATED 12Z... * HIGH ON FRONTAL PASSAGE AND WIND SHIFT AT 18Z +/- 1HR. * MEDIUM ON TIMING OF IFR LIFTING BACK TO MVFR WITH FROPA. * HIGH ON WIND DIRECTIONS PRE AND POST FRONTAL...MODERATE IN SUSTAINED AND GUST SPEEDS EITHER SIDE OF THE COLD FRONT. * HIGH ON CLEARING SKY DURING LATE AFTERNOON-EARLY EVENING. TRS //OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z... THURSDAY NIGHT...VFR...NO SIG WX. FRIDAY...VFR...NO SIG WX. SATURDAY...VFR...MODERATE SW WINDS. SUNDAY...VFR...NO SIG WX. MONDAY...VFR...NO SIG WX. TUESDAY...VFR. SLIGHT CHANCE SHOWERS. TRS && .MARINE... 411 AM CST WINDS WILL GRADUALLY DIMINISH EARLY THIS MORNING BUT STILL BE GUSTING TO 35 KT ON CENTRAL AND ESPECIALLY SOUTHERN LAKE MI UNTIL MID MORNING AS LOW PRESSURE LIFTS NORTHEAST FROM WI INTO ONTARIO BY MIDDAY. AS IT DOES IT WILL SWEEP A COLD FRONT ACROSS LAKE MICHIGAN SHIFTING WINDS TO OUT OF THE NORTHWEST. THERE WILL BE A SHORT LULL IN THE WINDS AS THE COLD FRONT PASSES. THEY WILL WILL INCREASE AGAIN POST FRONTAL THOUGH ARE EXPECTED TO REMAIN BELOW GALE FORCE THIS AFTERNOON AND TONIGHT AS HIGH PRESSURE BUILDING SOUTHEASTWARD ACROSS THE ROCKIES AND INTO THE PLAINS MAINTAINS A FAIRLY STRONG PRESSURE GRADIENT ACROSS THE REGION DESPITE THE LOW MOVING NE TO THE CENTRAL QUEBEC BY EVENING. WINDS DIMINISH AND BACK TO SOUTHWEST DURING FRIDAY BEFORE STRENGTHENING AGAIN LATE FRIDAY AS ANTHER LOW DEEPENS AS IT MOVES FROM SOUTHERN ALBERTA EAST TO WESTERN ONTARIO. GALE FORCE WINDS ARE A POSSIBILITY LATER FRIDAY NIGHT INTO SATURDAY AS THE LOW MOVES ACROSS S CENTRAL CANADA. AS THE LOW CONTINUES EASTWARD ACROSS ONTARIO SATURDAY A TRAILING COLD FRONT WILL MOVE INTO THE UPPER GREAT LAKES BRINGING ANOTHER WIND SHIFT TO OUT OF THE NORTHWEST. && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...GALE WARNING...LMZ080-LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777- LMZ779-LMZ868-LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 9 AM WEDNESDAY. SMALL CRAFT ADVISORY...ILLINOIS NEARSHORE WATERS UNTIL 10 PM WEDNESDAY. SMALL CRAFT ADVISORY...INDIANA NEARSHORE WATERS UNTIL 4 PM THURSDAY. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
945 AM EST WED NOV 6 2013 .SYNOPSIS... HIGH PRESSURE WILL MAINTAIN NORTHEAST WINDS ACROSS THE AREA THIS MORNING. TEMPERATURES WILL START TO WARM TODAY AS HIGH PRESSURE SHIFTS OFF THE COAST AND SOUTHERLY WINDS DEVELOP. TEMPERATURES WILL REMAIN WARM INTO THURSDAY AHEAD OF AN APPROACHING COLD FRONT. THE FRONT WILL MOVE OFF THE COAST LATE THURSDAY AND WILL BE FOLLOWED BY COOLER AND DRIER WEATHER INTO NEXT WEEK. && .NEAR TERM /THROUGH TONIGHT/... AS OF 930 AM WEDNESDAY...STRONG UPPER LEVEL HIGH PRESSURE SITS JUST OFF THE SOUTHEAST U.S. COAST...WHILE AT THE SURFACE THE HIGH IS CENTERED JUST SOUTH OF THE NEWFOUNDLAND CANADA COAST. A LONG EASTERLY FETCH AT THE SURFACE CROSSES OVER A THOUSAND MILES OF WESTERN ATLANTIC OCEAN WATER BEFORE COMING ONSHORE INTO THE CAROLINAS. PLENTY OF MOISTURE IN THE LOWEST 7500 FEET OF THE ATMOSPHERE IS PRODUCING AREAS OF EXTENSIVE ALTOCUMULUS...SOME OF WHICH ARE PRODUCING SHOWERS OFF THE COAST. ISENTROPIC LIFT ALONG THE 300K THETA SURFACE IS EXPECTED TO INCREASE BY LATE AFTERNOON IN THE CAPE FEAR REGION WITH SKIES BECOMING CLOUDY AND AN INCREASING SHOWER POTENTIAL NOTED. FARTHER INLAND THERE SHOULD BE ABOUT A 50/50 MIX OF CLOUDS AND SUN TODAY. WITH THE OVERALL AIRMASS QUITE MILD FOR THIS DATE HIGHS SHOULD REACH THE LOWER 70S DESPITE THE CLOUDS...A LITTLE ABOVE NORMAL. FOR TONIGHT I HAVE MADE SOME UPWARD CHANGES TO POPS...PARTICULARLY IN THE CAPE FEAR REGION WHERE THE LATEST HRRR AND 06Z GFS SHOW A CONCENTRATED "STREAMER" OF MOISTURE AND ISENTROPIC LIFT MOVING NORTHWARD FROM THE GULF STREAM SOUTH OF CAPE FEAR. THIS IS ACTUALLY A FAIRLY TYPICAL SCENARIO IN WEAKLY FORCED VEERING WIND SITUATIONS...AND ASSUMING 12Z MODELS CONTINUE TO SHOW THIS POTENTIAL I PLAN TO INCREASE POPS IN THE WILMINGTON AREA OVER 50 PERCENT FOR TONIGHT. FARTHER INLAND CURRENTLY POPS FOR TONIGHT ARE IN THE 20-30 PERCENT REGION AS IT APPEARS THE LIMITED DEPTH OF MOISTURE MAY NOT MAKE IT TOO FAR INLAND BEFORE THE 850-700 MB FLOW ATTAINS A BIT OF WESTERLY COMPONENT...SHUTTING DOWN ANY ATLANTIC INFLOW. 12Z MODELS SHOULD HELP REFINE THIS POTENTIAL AS WELL. && .SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... AS OF 230 AM WEDNESDAY...COLD FRONT SLATED TO MOVE ACROSS THE AREA DURING THE FIRST HALF OF THE PERIOD WILL BRING BELOW CLIMO TEMPS FOR THE END OF THE WEEK. FRONT ITSELF MAY PASS DRY WITH THE BEST PRECIP CHANCES BEING ASSOCIATED WITH A PRE-FRONTAL TROUGH PUSHING OFF THE COAST AS THE PERIOD BEGINS. BY THE TIME THE FRONT REACHES THE CAROLINAS THE 5H TROUGH WILL HAVE WEAKENED CONSIDERABLY AND THE ORIENTATION OF THE 5H RIDGE SOUTH OF THE AREA DOES NOT ALLOW FOR A SIGNIFICANT GULF MOISTURE TAP. ADDITIONALLY THE DYNAMICS ARE DISPLACED WELL NORTH OF THE AREA AND BAGGINESS IN THE GRADIENT OFF THE COAST POINTS TO DEVELOPMENT OF WEAK LOW ON THE TAIL END OF THE TROUGH...FURTHER LIMITING THE FRONTS ABILITY TO PRODUCE PRECIP. INHERITED SLIGHT CHANCE POP INLAND FOR FIRST HALF OF THU IS REASONABLE BUT WILL BUMP UP POP TO CHC ALONG THE COAST FOR FIRST PART OF THU. A MUCH DRIER AND COOLER AIR MASS BUILDS IN BEHIND THE FRONT THU NIGHT INTO FRI. PRECIPITABLE WATER VALUES DROP UNDER 0.25 INCH BY FRI MORNING AND REMAIN BELOW 0.30 INCH THROUGH THE END OF THE PERIOD. ALTHOUGH THE DEEP DRY AIR WILL LEAD TO SUNNY SKIES COLD ADVECTION...WHICH WILL CONTINUE INTO FRI NIGHT...WILL KEEP TEMPERATURES BELOW TO WELL BELOW CLIMO. SOME AREAS WILL SEE HIGHS AROUND 60 FRI WITH LOWS IN THE MID 30S TO AROUND 40 FRI NIGHT. COMBINATION OF TIGHT GRADIENT AND MIXING OF STRONGER WINDS ALOFT COULD MAKE FRI A BREEZY DAY. BOUNDARY LAYER WINDS START TO WEAKEN FRI NIGHT BUT IT MAY BE A CASE OF TOO LITTLE TOO LATE AS FAR AS STRONG RADIATIONAL COOLING IS CONCERNED. && .LONG TERM /SATURDAY THROUGH TUESDAY/... AS OF 230 AM WEDNESDAY...FLAT MID LEVEL PATTERN WILL LEAD TO A RELATIVELY QUIET PERIOD WITH COLDEST AIR REMAINING TRAPPED WELL TO THE NORTH. HIGH PRESSURE IN CONTROL SAT WILL BE REINFORCED BY SECOND AREA OF HIGH PRESSURE FOLLOWING COLD FRONT EARLY SUN. FRONT PASSES DRY WITH NEXT TO NO COLD AIR...THE ONLY THING SIGNIFYING ITS PASSAGE WILL BE WINDS SHIFTING FROM SOUTHERLY TO NORTHWEST. DURING THE MIDDLE OF NEXT WEEK CLOUD COVER MAY START TO INCREASE AS MOISTURE ASSOCIATED WITH LOW PRESSURE DEVELOPING OVER THE MIDWEST SPREADS EAST. THIS SYSTEM IS UNLIKELY TO HAVE ANY SIGNIFICANT IMPACT ON THE CAROLINAS BEFORE THE END OF THE PERIOD. ZONAL FLOW ALOFT WILL HELP KEEP TEMPERATURES NEAR CLIMO THROUGH THE PERIOD...WITH THE EXCEPTION OF SAT WHEN TEMPERATURES MAY RUN A LITTLE BELOW CLIMO. && .AVIATION /12Z WEDNESDAY THROUGH SUNDAY/... AS OF 12Z...SURFACE RIDGE HOLDING IN...HOWEVER SOME MID CLOUDS ARE MOVING ONSHORE THIS MORNING. THERE MAY EVEN BE A SPRINKLE HERE AND THERE...MAINLY NEAR THE COAST DUE TO A VERY WEAK COASTAL TROUGH. WINDS WILL BE MAINLY NORTHEASTERLY THIS MORNING...BECOMING A BIT MORE EASTERLY THIS AFTERNOON. THE MID CLOUDS WILL CONTINUE TO BE IN AND OUT THROUGH THIS EVENING. A CONTINUED CHANCE OF A SPRINKLE OVERNIGHT AS COASTAL TROUGH SHARPENS A BIT. EXTENDED OUTLOOK...CHANCE OF SHOWERS WITH MVFR CIGS POSSIBLE LATE WEDNESDAY INTO THURSDAY. OTHERWISE VFR. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 930 AM WEDNESDAY...SMALL CRAFT ADVISORIES REMAIN POSTED FOR 6-7 FOOT SEAS MAINLY AT THE OUTER MARGIN OF THE SOUTH CAROLINA COASTAL WATERS AND BEYOND 5-10 MILES FROM SHORE ACROSS THE NC WATERS. THE CULPRIT IS A 1500+ MILE EASTERLY FETCH ACROSS MOST OF THE WESTERN ATLANTIC PRODUCED BY 1035 MB HIGH PRESSURE SOUTH OF NEWFOUNDLAND CANADA. AS THIS HIGH WEAKENS AND THE SYNOPTIC FLOW VEERS MORE SOUTHERLY WITH THE APPROACHING COLD FRONT THE FETCH SHOULD DIMINISH CONSIDERABLY DURING THE AFTERNOON. CHANGES WITH THIS MORNING UPDATE WERE GENERALLY MINOR...LIMITED TO COVERAGE OF SHOWERS BASED ON CURRENT RADAR IMAGERY AND RUC/HRRR PROGS THROUGH THE AFTERNOON. SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... AS OF 230 AM WEDNESDAY...SOUTHERLY FLOW AT THE START OF THE PERIOD WILL QUICKLY BECOME WESTERLY AS PRE-FRONTAL TROUGH CROSSES THE WATERS. STRENGTH OF OFFSHORE FLOW WILL BE LIMITED UNTIL AFTER PASSAGE OF COLD FRONT LATER THU. PINCHED PRESSURE GRADIENT AND COLD ADVECTION THU NIGHT AND FRI WILL LEAD TO OFFSHORE FLOW IN THE 20 TO 25 KT RANGE WITH GUSTS EXCEEDING 30 KT. GIVEN OFFSHORE TRAJECTORY AND LIMITED FETCH CONFIDENCE IN SEAS WITHIN 20 NM REACHING 6 FT FOR ALL ZONES IS LOW...THOUGH WIND SPEEDS ARE LIKELY TO BE ENOUGH TO WARRANT SCA THU NIGHT AND FRI MORNING. WIND SPEEDS DECREASE LATE FRI AND FRI NIGHT AND VEER TO NORTHEAST AS CENTER OF HIGH PRESSURE MOVES INTO THE CENTRAL APPALACHIANS AND THE GRADIENT WEAKENS. SEAS 2 TO 4 FT EARLY THU WILL BUILD TO 4 TO 7 FT THU NIGHT AND FRI. THE DECREASE IN SPEED AND VEERING OF WINDS LATER FRI AND FRI NIGHT WILL KNOCK SEAS BACK TO 3 TO 5 FT FOR THE LATER HALF OF THE PERIOD. LONG TERM /SATURDAY THROUGH SUNDAY/... AS OF 230 AM WEDNESDAY...HIGH PRESSURE WILL DOMINATE THE PERIOD...BROKEN BY PASSAGE OF RELATIVELY WEAK COLD FRONT SAT NIGHT INTO SUN. WINDS AND SEAS WILL BE DECREASING SAT AS HIGH PRESSURE SETTLES OVER THE WATERS AND THEN DRIFTS TO THE SOUTH SAT NIGHT. PASSAGE OF COLD FRONT LATE SAT NIGHT IS LIKELY TO BE MORE OF A WIND SHIFT THAN A TRUE FRONTAL PASSAGE. THERE WILL BE A SLIGHT INCREASE IN WINDS BEHIND THE FRONT AS GRADIENT BECOMES A LITTLE MORE DEFINED AND SLIGHTLY COOLER AIR BUILDS IN. SPEEDS WILL INCREASE FROM AROUND 10 KT ON SAT TO 10 TO 15 KT FOR SUN. SEAS WILL VARY FROM AROUND 2 FT TO 2 TO 3 FT. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL NOON EST TODAY FOR AMZ254-256. SMALL CRAFT ADVISORY UNTIL 6 PM EST THIS EVENING FOR AMZ250- 252. && $$ NEAR TERM...TRA SHORT TERM...III LONG TERM...III AVIATION...43
AREA FORECAST DISCUSSION
NWS SPOKANE WA
420 AM PST Wed Nov 6 2013 .SYNOPSIS... A wet storm system is expected for tonight into Thursday. This storm system will be milder with rain in the valleys and snow for the mountains. Gusty winds will be likely. Cool, showery, and unstable conditions will be coming for the weekend and into next week. && .DISCUSSION... Today and Tonight..Anti-cyclonic curved ridge axis and associated jet stream will remain parked over the Inland Northwest this morning...with a weak shortwave trough embedded on the left front quadrant of the jet over NE Washington. This shortwave is expected to weaken significantly this morning as it dips slowly to the southeast while the upper level jet begins to buckle northward into BC. However as long as the shortwave persists it will still be able to tap into a very moist surface-700 mb layer and should be able to wring light precipitation out of the atmosphere. Radar loops this morning have consistently shown showers over the Idaho Panhandle ahead of this feature...and the models have not handled it all that well. Fortunately the RUC model seems to buck that trend. If we follow its solution...the low level southwest winds ahead of the trough which are leading to good isentropic and orographic ascent will gradually turn to the northwest and allow drier air to spill into the area. This will result in a decreasing shower threat through the morning...but up to an inch of snow is certainly possible before all is said and done. Most of the snow will occur over eastern sections of Kootenai, Benewah, Latah counties as well as most of Shoshone County but above valley elevations as surface temps are generally above freezing. Farther west...there is a widespread stratus deck that will likely remain in place through much of the day and could continue to produce some light drizzle early as weak ascent will persist through a much shallower moist layer. Otherwise...the weather looks rather benign for much of the day. For late this afternoon and tonight...the break in the weather will come to an end as the ridge axis shifts east of the forecast area and a warm front moves into the area from the southwest. This front will bring a significant influx of moisture and a rapid increase in the chances for precipitation overnight. Warmer air will also filter into the area....and snow levels will steadily rise from around 3-4k feet late this afternoon (lower across the northeast Cascades) to nearly 6-7.5k by early Thursday morning. That means the precipitation will largely fall as rain over all valley locations...however lower snow levels will persist over the northeast Cascades due to cold air damming and the warm air won`t quite make it to the Canadian border by morning. The heaviest amounts of precipitation will likely fall near the Cascade Crest due to persistent south-southeast 850 mb flow. Values there could range from .25-.60"...much of which will fall as snow at elevations at or above 3500 feet. This will likely impact the passes in that area...including the North Cascades Highway...Loup Loup and Stevens Passes with heavy snow possible. That threat will continue through Thursday and consequently we have issued a winter weather advisory for snow. Just how fast the cold air can mix out will be the big question and will largely determine how much snow accumulates. Looks like the cold air will remain most stubborn north of Lake Chelan and impact portions of the North Cascade Highway. Elsewhere look for widespread rain to impact most areas overnight with amounts ranging from .05 to .15 inches. fx Thursday through Sunday night...Very moist low pressure system will bring increasing precipitation to the Inland Northwest on Thursday. A subtropical moisture tap will be drawn into the area which combined with isentropic lift leads to a high confidence forecast of all areas getting precip. The flow at 850mb will back to the south Thursday morning with warmer air spreading into the region with snow levels rising to 6000-7000 feet from Wenatchee to Spokane to Kellogg and points south resulting in rain even in most mountains south of this line. As usual colder air will be tough to scrub near the Canadian border with GFS and NAM showing wet bulb zero heights near 3000 feet in the morning...but should eventually rise to 5000 feet in the afternoon as warmer air continues to push northward with 850mb winds out of the south at 30-40 knots. The cold front moves into the region in the afternoon for continued wet conditions...with the front exiting the Idaho Panhandle early Thursday evening. Precipitation totals from the models show 1-1.5 inches for the Cascade crest, around an inch for the Idaho Panhandle, and 0.5-1.00 inches for Eastern Washington...with up to a half inch for the Wenatchee area and Columbia Basin. These values make sense given the subtropical moisture tap. Following the cold front moist zonal flow will favor showers in the orographic favored areas of the Cascade crest and Idaho Panhandle. Snow levels behind the front fall to 3000-4000 feet supporting the potential for light snow accumulations for the Cascade passes and Lookout Pass Thursday night. Breezy winds are also expected behind the front on the palouse and in the Blue Mountains where the strongest pressure gradient and instability will be. In fact the NAM shows a marginal thunder threat in these areas with the front passage late Thursday afternoon and evening. For now will leave thunder out due to low confidence of this occurring at this time. Another fast moving wave tracks through in the zonal flow Friday which will likely enhance the shower activity in the favored west flow upslope areas with a chance of showers backfilling into Eastern Washington. Downslope should dominate in the lee of the Cascades with Wenatchee, Omak, and Moses Lake likely remaining dry on Friday. Friday night into Saturday generally dry weather is favored as the next low pressure system drops south along 140W building a weak ridge over the Inland Northwest. Saturday night through Sunday night models show increased moisture moving in with the GFS lifting a warm front into the area while the ECMWF shows a stalled frontal boundary over Eastern Washington and North Idaho. While there are differences in the details the trend will be for increasing precipitation chances. Snow levels look to remain above valley floors except for elevations above 2000-2500 feet along the East Slopes of the Cascades and near the Canadian Border where wet snow is possible in the higher valleys. JW Monday and Tuesday: Monday is expected to be pretty quiet with a ridge pattern dominating the region. The models are indicating a Low approaching the Pacific Coast as the ridging breaks down. The timing of the system is expected to be on Monday evening and bring a warm front through the region. Rain showers are expected for the Lower Columbia Basin. The higher elevations will get snow and the valleys will be impacted by a rain/snow mix. The temperatures are expected to be in line with the prior days. /JDC && .AVIATION... 12Z TAFS: Yet another low confidence forecast is at hand as stratus and IFR/MVFR cigs will impact every forecast site at least through 18z. Most of the ceiling heights this morning were right around 1k feet...and are expected rapidly vacillate on either side of that critical IFR/MVFR threshold. Generally speaking through...we should see a slow lifting of the ceiling heights through 18z. None of the sites will experience any weather aside from COE...where some light snow showers will remain possible through 16z or so. By afternoon...we expect much of the lower stratus to break up...and most sites will briefly improve into the VFR category. We went with timing this improvement around 18z...based on conditional climatology and BUFKIT data...however would not be terribly surprised if things persist a little past that time. Between 00z-06z tonight...the stratus will certainly breakup with the approach of a strong warm front. This will gradually spread rain from SW to NE overnight...and ceilings will once again likely lower to MVFR heights. fx && .PRELIMINARY POINT TEMPS/POPS... Spokane 42 36 45 37 45 31 / 10 60 100 60 40 20 Coeur d`Alene 41 35 43 36 44 31 / 20 60 100 80 60 30 Pullman 44 39 47 38 45 33 / 10 40 100 70 40 20 Lewiston 48 41 51 42 52 35 / 10 40 90 60 30 20 Colville 44 34 41 36 46 31 / 10 80 100 50 40 20 Sandpoint 41 33 41 35 43 31 / 10 60 100 80 80 40 Kellogg 41 34 42 35 39 31 / 30 70 100 100 80 40 Moses Lake 45 38 48 35 53 30 / 10 50 80 20 10 10 Wenatchee 43 35 45 36 51 33 / 10 50 70 10 10 10 Omak 43 35 42 33 47 29 / 0 70 100 20 10 10 && .OTX WATCHES/WARNINGS/ADVISORIES... ID...None. WA...Winter Weather Advisory from 4 PM this afternoon to 4 PM PST Thursday for East Slopes Northern Cascades. && $$
AREA FORECAST DISCUSSION
NWS SPOKANE WA
303 AM PST Wed Nov 6 2013 .SYNOPSIS... A wet storm system is expected for tonight into Thursday. This storm system will be milder with rain in the valleys and snow for the mountains. Gusty winds will be likely. Cool, showery, and unstable conditions will be coming for the weekend and into next week. && .DISCUSSION... Today and Tonight..Anti-cyclonic curved ridge axis and associated jet stream will remain parked over the Inland Northwest this morning...with a weak shortwave trough embedded on the left front quadrant of the jet over NE Washington. This shortwave is expected to weaken significantly this morning as it dips slowly to the southeast while the upper level jet begins to buckle northward into BC. However as long as the shortwave persists it will still be able to tap into a very moist surface-700 mb layer and should be able to wring precipitation out of the atmosphere. Radar loops this morning have consistently shown showers over the Idaho Panhandle ahead of this feature...and the models have not handled it all that well. Fortunately the RUC model seems to buck that trend. If we follow its solution...the low level southwest winds ahead of the trough which are leading to good isentropic and orographic ascent will gradually turn to the northwest and allow drier air to spill into the area. This will result in a decreasing shower threat through the morning...but up to an inch of snow is certainly possible before all is said and done. Most of the snow will occur over eastern sections of Kootenai, Benewah, Latah counties as well as most of Shoshone County but above valley elevations as surface temps are generally above freezing. Farther west...there is a widespread stratus deck that will likely remain in place through much of the day and could continue to produce some light drizzle early as weak ascent will persist through a much shallower moist layer. Otherwise...the weather looks rather benign for much of the day. For late this afternoon and tonight...the break in the weather will come to an end as the ridge axis shifts east of the forecast area and a warm front moves into the area from the southwest. This front will bring a significant influx of moisture and a rapid increase in the chances for precipitation overnight. Warmer air will also filter into the area....and snow levels will steadily rise from around 3-4k feet late this afternoon (lower across the northeast Cascades) to nearly 6-7.5k by early Thursday morning. That means the precipitation will largely fall as rain over all valley locations...however lower snow levels will persist over the northeast Cascades due to cold air damming and the warm air won`t quite make it to the Canadian border by morning. The heaviest amounts of precipitation will likely fall near the Cascade Crest due to persistent south-southeast 850 mb flow. Values there could range from .25-.60" much of which will fall as snow at elevations at or above 3500 feet. This will likely impact the passes in that area...including Rainy...Loup Loup and Stevens with heavy snow possible. That threat will continue through Thursday and consequently we have issued a winter weather advisory for snow. Just how fast the cold air can mix out will be the big question and will largely determine how much snow accumulates. Looks like the cold air will remain most stubborn along the North Cascade Highway. Elsewhere look for widespread precipitation to impact most areas overnight. fx Thursday through Sunday night...Very moist low pressure system will bring increasing precipitation to the Inland Northwest on Thursday. A subtropical moisture tap will be drawn into the area which combined with isentropic lift leads to a high confidence forecast of all areas getting precip. The flow at 850mb will back to the south Thursday morning with warmer air spreading into the region with snow levels rising to 6000-7000 feet from Wenatchee to Spokane to Kellogg and points south resulting in rain even in most mountains south of this line. As usual colder air will be tough to scrub near the Canadian border with GFS and NAM showing wet bulb zero heights near 3000 feet in the morning...but should eventually rise to 5000 feet in the afternoon as warmer air continues to push northward with 850mb winds out of the south at 30-40 knots. The cold front moves into the region in the afternoon for continued wet conditions...with the front exiting the Idaho Panhandle early Thursday evening. Precipitation totals from the models show 1-1.5 inches for the Cascade crest, around an inch for the Idaho Panhandle, and 0.5-1.00 inches for Eastern Washington...with up to a half inch for the Wenatchee area and Columbia Basin. These values make sense given the subtropical moisture tap. Following the cold front moist zonal flow will favor showers in the orographic favored areas of the Cascade crest and Idaho Panhandle. Snow levels behind the front fall to 3000-4000 feet supporting the potential for light snow accumulations for the Cascade passes and Lookout Pass Thursday night. Breezy winds are also expected behind the front on the palouse and in the Blue Mountains where the strongest pressure gradient and instability will be. In fact the NAM shows a marginal thunder threat in these areas with the front passage late Thursday afteroon and evening. For now will leave thunder out due to low confidence of this occurring at this time. Another fast moving wave tracks through in the zonal flow Friday which will likely enhance the shower activity in the favored west flow upslope areas with a chance of showers backfilling into Eastern Washington. Downslope should dominate in the lee of the Cascades with Wenatchee, Omak, and Moses Lake likely remaining dry on Friday. Friday night into Saturday generally dry weather is favored as the next low pressure system drops south along 140W building a weak ridge over the Inland Northwest. Saturday night through Sunday night models show increased moisture moving in with the GFS lifting a warm front into the area while the ECMWF shows a stalled frontal boundary over Eastern Washington and North Idaho. While there are differences in the details the trend will be for increasing precipitation chances. Snow levels look to remain above valley floors except for elevations above 2000-2500 feet along the East Slopes of the Cascades and near the Canadian Border where wet snow is possible in the higher valleys. JW Monday and Tuesday: Monday is expected to be pretty quiet with a ridge pattern dominating the region. The models are indicating a Low approaching the Pacific Coast as the ridging breaks down. The timing of the system is expected to be on Monday evening and bring a warm front through the region. Rain showers are expected for the Lower Columbia Basin. The higher elevations will get snow and the valleys will be impacted by a rain/snow mix. The temperatures are expected to be in line with the prior days. /JDC && .AVIATION... 06Z TAFS: Primarily IFR/LIFR conditions expected to linger in the stable environment behind the exiting system, impacting the KGEG to KCOE and KPUW area. Some -sn/-fzdz/-dz will affect extreme NE WA and the northern panhandle overnight and possibly in the vcnty of these sites as well, but the threat will diminish overnight. Conditions may be slow to improve through the day Wednesday, potentially not improving beyond IFR/MVFR conditions until after noon. KMWH/KEAT is expected to remain IFR/MVFR through the night, with possible fog development though 20Z. KLWS is expected to degrade toward MVFR through the night, with some improvement in the morning. Confidence is lower for conditions in vcnty of KEAT/KMWH/KLWS. The next wet weather system will push into the KEAT area just before 06Z Thursday. /EK && .PRELIMINARY POINT TEMPS/POPS... Spokane 42 36 45 37 45 31 / 10 60 100 60 40 20 Coeur d`Alene 41 35 43 36 44 31 / 20 60 100 80 60 30 Pullman 44 39 47 38 45 33 / 10 40 100 70 40 20 Lewiston 48 41 51 42 52 35 / 10 40 90 60 30 20 Colville 44 34 41 36 46 31 / 10 80 100 50 40 20 Sandpoint 41 33 41 35 43 31 / 10 60 100 80 80 40 Kellogg 41 34 42 35 39 31 / 30 70 100 100 80 40 Moses Lake 45 38 48 35 53 30 / 10 50 80 20 10 10 Wenatchee 43 35 45 36 51 33 / 10 50 70 10 10 10 Omak 43 35 42 33 47 29 / 0 70 100 20 10 10 && .OTX WATCHES/WARNINGS/ADVISORIES... ID...None. WA...Winter Weather Advisory from 4 PM this afternoon to 4 PM PST Thursday for East Slopes Northern Cascades. && $$
AREA FORECAST DISCUSSION
NWS PUEBLO CO
318 PM MST WED NOV 6 2013 .SHORT TERM...(THIS EVENING THROUGH THURSDAY) ISSUED AT 249 PM MST WED NOV 6 2013 CURRENTLY... BRISK NORTHWEST FLOW IS PRODUCING WIND GUSTS TO NEAR 40KTS ACROSS THE MOUNTAINS AND I-25 CORRIDOR OF SOUTHEASTERN COLORADO THIS AFTERNOON. WEAK INSTABILITY ALSO PRODUCED SOME VERY LIGHT SNOW SHOWERS AT KLXV AROUND 19Z/20Z. ANY REMAINING SNOW SHOWERS AND CLOUDS WILL DISSIPATE BY LATE THIS AFTERNOON. TONIGHT... NORTHWEST FLOW WILL CONTINUE TO PRODUCE CLEAR SKIES AND DRY CONDITIONS ACROSS THE AREA. THE BIGGEST FORECAST CHALLENGE ARE LOW TEMPERATURES AND WINDS ACROSS THE MOUNTAINS OVERNIGHT. LATEST HRRR AND RAP RUNS KEEP WINDS AT 10-15KTS THROUGH EARLY THURSDAY MORNING AROUND THE LEADVILLE AREA AND THE PIKE`S PEAK REGION. I HAVE INCREASED LOW TEMPERATURES IN THESE AREAS TO MATCH EC/MET/MAV GUIDANCE. VALLEY AND LOCATIONS ON THE PLAINS WILL HAVE A CLEAR/COLD NIGHT. THURSDAY... AFTER A COLD START TEMPERATURES WILL WARM NICELY UNDER SUNNY SKIES. 700MB TEMPERATURES WARM UP TO 2-4C PER THE 18Z NAM12. UPPER LEVEL FLOW WILL BE COME MORE ZONAL/WESTERLY THROUGHOUT THE DAY. BUFKIT SOUNDINGS SHOW ALL LOCATIONS MIXING FAIRLY WELL...WITH WESTERLY WINDS IN THE MOUNTAINS...AND SOUTHERLY WINDS ACROSS THE PLAINS. -PC .LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 249 PM MST WED NOV 6 2013 THURSDAY NIGHT THROUGH SATURDAY...AN UPPER DISTURBANCE WILL TRACK ACROSS THE NORTHERN ROCKIES ON FRI...TIGHTENING THE PRESSURE GRADIENT ACROSS COLORADO AND PRODUCING GUSTY CONDITIONS FOR THE MTS AND AT TIMES FOR THE E PLAINS. THE WESTERLY DOWNSLOPE FLOW WILL HELP TEMPS WARM NICELY...WITH FORECAST MAX TEMPS IN THE UPPER 60S AND 70S FOR THE PLAINS...50S AND 60S FOR THE HIGH VALLEYS. AS THE DISTURBANCE CONTINUE EAST THROUGH THE NIGHT...IT WILL PUSH COLD AIR DOWN ACROSS WY AND INTO CO. A DRY COLD FRONT IS EXPECTED TO CROSS THE PALMER DVD AND MOVE INTO THE CWA LATE FRI EVE...WITH MUCH COOLER TEMPS THEN EXPECTED FOR SAT. AT THIS TIME...NO PCPN IS EXPECTED. SUNDAY THROUGH TUESDAY...ZONAL FLOW ALOFT WITH WEAK RIDGING WILL CONTINUE TO BE THE CASE THROUGH THE FIRST HALF OF THE NEXT WORK WEEK. DRY CONDITIONS WILL PREVAIL...WITH MAX TEMPS EACH DAY IN THE 50S TO LOWER 60S WHICH WILL BE RIGHT AT SEASONAL NORMS. WEDNESDAY...GFS AND EC MODELS INDICATE THAT THE UPPER RIDGE WILL BREAK DOWN STARTING LATE TUE NIGHT...WITH AN UPPER TROUGH CROSSING MT AND WY ON WED AND BRINGING THE CHANCE FOR SOME PCPN TO THE CWA ON WED. BEING SO FAR OUT...CONFIDENCE IS LOW ON THE TIMING...BUT DECIDED TO DROP MAX TEMPS ABOUT 5 F AND INTRODUCED SOME ISOLATED POPS. MOORE && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING) ISSUED AT 249 PM MST WED NOV 6 2013 VFR CONDITIONS ARE EXPECTED NEXT 24 HOURS AT ALL 3 TAF SITES..KALS...KCOS...AND KPUB. WINDS AT KCOS AND KPUB SHOULD CALM DOWN BY 02Z TONIGHT AND WILL BE LIGHT AND VARIABLE THROUGH 18Z WEDNESDAY. -PC && .PUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...PJC LONG TERM...MOORE AVIATION...PJC
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
1001 AM MST WED NOV 6 2013 .UPDATE... && .SHORT TERM...FAIRLY STRONG NORTHWEST FLOW ALOFT CURRENTLY OVER THE STATE WITH UPPER LEVEL JET NOSING INTO WYOMING. SATELLITE AND WEB CAMS SHOWING FAIRLY GOOD MOISTURE WEST OF THE CONTINENTAL DIVIDE. RADAR AND CAMS INDICATING SNOW SHOWERS ALONG THE DIVIDE...MAINLY WEST FACING SLOPES...AND OVER THE GORE AND PARK RANGES OF WESTERN JACKSON COUNTY. SHOWERS BEING GENERATED BY THE COMBINATION OF OROGRAPHICS AND ASCENT. CROSS SECTIONS SHOW THE MOISTURE CONTINUING THROUGH THE MORNING WITH SOME DECREASE DURING THE AFTERNOON. ALSO ASCENT WEAKENS AND BECOMES SUBSIDENT AS JET MAX MOVES OUT OF WYOMING. THUS SHOULD SEE SOME DECREASE IN THE SHOWERS. LATEST RAP GENERATES SOME LIGHT SHOWERS AND QPF ACROSS FAR NORTHEAST PLAINS THIS AFTERNOON...MAY BE A BIT OVERDONE GIVEN THE AMOUNT OF DESCENT EXPECTED. WINDS HAVE BEEN A BIT GUSTY IN AND NEAR FOOTHILLS AS GRADIENT BETWEEN UPPER RIDGE OVER THE GREAT BASIN AND TROUGH ACROSS PLAINS INCREASES A BIT. 1500 METER GRADIENT FROM GJT TO DEN HAS BEEN STEADILY INCREASING...CURRENTLY AT 7.57 MB. BY AFTERNOON...COMBINATION OF MIXING AND INCREASING SUBSIDENCE SHOULD HELP INCREASE WINDS ACROSS THE AREA. DID UPDATE FOR MORE CLOUDS AND SHOWERS ACROSS THE MOUNTAINS THIS MORNING...MAINLY ALONG THE DIVIDE. ALSO ADDED SOME LIGHT ACCUMULATION. ALSO ADDED A BIT MORE WIND IN AND NEAR THE FOOTHILLS BASED ON CURRENT TRENDS. REST OF FORECAST LOOK OKAY FOR NOW. .AVIATION...WINDS BEGINNING TO MIX TO THE SURFACE...AS SHOWING BY RECENT GUSTY WINDS AT KBJC. DID UPDATE FOR SOME GUSTS THERE...THOUGH WINDS HAVE RECENTLY DECREASED. BY 19Z WINDS TO BECOME MORE NORTHWEST AS MIXING CONTINUES. CURRENT GUSTS TO AROUND 25 KTS STILL LOOKING REASONABLE FOR KDEN AND KAPA...WITH GUSTS TO 30 KTS AT KBJC. WILL CONTINUE TREND OF CURRENT TAFS. && .PREV DISCUSSION... /ISSUED 338 AM MST WED NOV 6 2013/ SHORT TERM...TODAY AND TONIGHT...NORTHWEST FLOW ALOFT WILL PREVAIL. SHALLOW MOISTURE EMBEDDED IN THIS FLOW WILL PRODUCE CLOUDS AND SCATTERED TO ISOLATED SNOW SHOWERS OVER THE NORTH CENTRAL MOUNTAINS OF COLORADO. DOWNSLOPE WINDS WILL DRY THE AIR ON THE EAST SIDE OF THE MOUNTAINS. WINDS ARE GUSTY IN SPOTS THIS MORNING...LIKELY DUE TO MOUNTAIN WAVES. THE GUSTY WINDS WILL MIX DOWN THIS AFTERNOON ACROSS THE FRONT RANGE AND EASTERN PLAINS. THESE DOWNSLOPE WINDS WILL HELP INCREASE TEMPERATURES WITH HIGHS AROUND 50 DEGREES OVER NORTHEAST COLORADO. THE SNOW SHOWERS OVER THE MOUNTAINS WILL END THIS EVENING AS DRIER MOVES INTO THE AREA. SKIES WILL BE MOSTLY CLEAR TONIGHT AND ALLOW FOR GOOD RADIATIONAL COOLINGS. LOWS WILL FALL BELOW FREEZING AGAIN FOR MOST LOCATIONS WHERE THE WIND IS NOT BLOWING. LONG TERM...SWIFT NEARLY ZONAL JET FLOW OVER THE NORTHERN TIER STATES THROUGH THE START OF NEXT WEEK MEANS TRANQUIL MID-AUTUMN WEATHER CONDITIONS FOR THE FORECAST AREA. SEE LITTLE TO NO CHANCE OF PRECIP AND NEAR TO ABOVE AVERAGE TEMPERATURES DURING THE FRIDAY-TUESDAY TIME PERIOD. ONLY DISRUPTION IN THE TRANQUIL PICTURE OCCURS FRIDAY WHEN THE PASSAGE OF A SHORTWAVE TROUGH CAUSES THE NOSE OF A 100+ KNOT JET TO DIP SOUTH OVER SOUTHERN WYOMING FRIDAY MORNING. NAM DERIVED CROSS SECTIONS INDICATE A STEADY INCREASE IN THE CROSS MOUNTAIN WIND COMPONENT THURSDAY NIGHT WITH A 73KT SPEED MAXIMA ABOVE THE CREST OF THE FRONT RANGE (ABOUT 650 MBS) AS OF 15Z/FRIDAY. MODEL SHOWS SOME OF THIS MOUNTAIN TOP MOMENTUM MIGRATING DOWN THE LEESIDE OF THE FRONT RANGE FRIDAY MORNING/AFTERNOON WITH 30-40KTS DOWN TO AROUND THE 8500 FT LEVEL. BELOW THAT...WIND SPEEDS NO WHERE AS STRONG ACCORDING TO BOTH THE NAM AND GFS. NOT READY TO ISSUE ANY HIGH WIND HIGHLIGHTS AS MODELS CONTINUE TO TREND THIS SHORTWAVE TROUGH AND JET STREAM A BIT FARTHER NORTH WITH EACH RUN CYCLE. FOR NOW WILL CONTINUE TO INDICATE STRONG/GUSTY WESTERLY/DOWNSLOPE WINDS IN THE THURSDAY NIGHT/FRIDAY FORECAST PERIOD...MAINLY FOR THE FRONT RANGE AND ITS FOOTHILLS. WARMEST DAYS LOOK TO BE FRIDAY WITH ADIABATIC WARMING AND SUNDAY WITH DIABATIC HEATING WITH PASSING SHORTWAVE RIDGE. MONDAY AND TUESDAY OF NEXT WEEK LOOK NEARLY AS WARM AS SUNDAY WITH FURTHER BUILDING OF THE UPPER RIDGE OVER COLORADO. BY WEDNESDAY...MODELS HINTING AT A CHANGE TO COOLER/WETTER WEATHER WITH THE APPROACH OF A SHORTWAVE TROUGH. WILL TREND TOWARD THAT DIRECTION STARTING LATE ON TUESDAY. AVIATION...VFR CONDITIONS WILL PREVAIL THROUGH THE NEXT 24 HOURS WITH ONLY SOME HIGH CLOUDS AT TIMES ACROSS THE DENVER AREA. NORMAL SOUTHERLY DRAINAGE WINDS AT KDEN AND KAPA WILL BECOME NORTHWESTERLY AROUND 17Z. GUSTS TO 25 KNOTS WILL BE POSSIBLE THROUGH THE AFTERNOON. AT KBJC...WEST WINDS UP TO 30 KNOTS WILL PREVAIL THROUGH THE EARLY MORNING AND TURN NORTHWESTERLY THIS AFTERNOON. && .BOU WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...D-L LONG TERM....BAKER AVIATION...D-L
AREA FORECAST DISCUSSION
NWS TOPEKA KS
257 PM CST Wed Nov 6 2013 .SHORT TERM...(This Evening through Thursday) Issued at 257 PM CST WED NOV 6 2013 The 20Z water vapor imagery shows a upper level trough progressing east through the plains into the upper Midwest and MS river valley. Weak ridging was noted over the inter-mountain west with another shortwave trough approaching the pacific northwest coast. At the surface, a cool and much dryer ridge of high pressure has settled into the central plains. For tonight and Thursday, dry and cool weather is expected to persist as the surface ridge keeps dry air over the forecast area. Additionally there is no obvious wave within the northwest flow aloft to suggest any forcing for precip. The low level saturation that has allowed the STRATOCU deck to linger over eastern KS through the afternoon is expected to eventually mix out and/or move east. Latest visible satellite seems to support the RAP and HRRR PROGS of the low level saturation dissipating. So think tonight will eventually become mostly clear. Am a little concerned about the formation of fog overnight since the boundary layer moisture has not mixed out and cross over temps are 3 to 5 degrees above the forecast min temps. The one thing against a good radiational fog is that the models keep the center of the surface ridge over western KS and the winds never go calm with lower dewpoint temps advecting in from the west through the night. Think this may be enough to limit any fog development to the favored low spots near bodies of water where the winds are most likely to be light and variable. Thursday should be sunny with a dry northwest flow aloft and the surface ridge still over eastern KS. Because of this there does not look to be a lot of low level warm air advection tomorrow so highs may struggle to warm into the mid 50s. .LONG TERM...(Thursday Night through Wednesday) Issued at 257 PM CST WED NOV 6 2013 Winds and cloud cover should steadily increase late Thursday night into Friday on the south end of a rather potent wave moving east through the Dakotas. Clouds will be of the high variety with still dry low to mid levels, limiting any precipitation chances. Specifics on how fast and thick the clouds are Tuesday night will play a large role in how cool temps will fall as southwest winds ramp up just off the surface through the night. Expect winds and clouds to hold off the longest in the south and east for the coolest temps there. A quite windy Friday remains to be expected, though the strongest winds may be a bit farther east, with near advisory levels possible for much of the area. Overnight and early day warm air advection should push temps well into the 60s. Elevated fire danger is still anticipated in the warm, dry, and windy boundary layer. The modified Pacific cold front with the Dakotas wave sinks in late Friday night into Saturday and should bring little cooling and much lighter winds. Zonal flow aloft becomes more northwesterly by Monday as an upper trof off the west coast deepens. Modest moisture return in isentropic lift may still be enough for a few showers Monday night into Tuesday. The main periods of question are for Tuesday night into Wednesday. The 12Z GFS and ECMWF are in rather strong agreement with a shortwave diving south into the Northern Plains and western Great Lakes Tuesday and on southeast through the mid Mississippi Valley Tuesday night and Wednesday. The source region of the airmass is northern Alaska and Yukon, but does linger for 12-24 hours in southern Canada before coming into the CONUS, and snowpack in this area does not appear to be now or look likely to increase much before its arrival. Still, the operational runs drop 850mb temps well below 0 C with its passage and suggest one of the coldest days of the cold season so far. The ensembles show a rather large spread in temps and height fields however, and this is not unexpected with this smaller scale wave coming through a somewhat complex pattern. Will suggest a cooling trend and some chance for liquid precipitation at this point but confidence is low. && .AVIATION...(For the 18Z TAFs through 18Z Thursday Afternoon) Issued at 1135 AM CST WED NOV 6 2013 RAP and HRRR solutions show the low level saturation hanging on through much of the afternoon. With satellite imagery showing a decent STRATOCU deck extending upstream into NEB, will hang onto MVFR CIGS until the late afternoon. Am a little concerned for some shallow ground fog developing late tonight. The main hiccup in fog formation is the models indicating a weak surface trough moving through northeast KS overnight implying some mixing could occur. But if skies clear out and the boundary layer decouples it may not matter that a trough propagates through the area. Therefore think the chances for ground fog within the KS river valley are high enough to include a mention in the TOP and MHK terminals. && .TOP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...53 LONG TERM...65 AVIATION...Wolters
AREA FORECAST DISCUSSION
NWS TOPEKA KS
1135 AM CST Wed Nov 6 2013 ...AVIATION UPDATE... .SHORT TERM...(Today and Tonight) Issued at 318 AM CST WED NOV 6 2013 Quiet weather is expected through tomorrow morning as the mid level trough axis progresses through the region. Cooler air is working into the CWA behind the front with temps in mid 30s already in north central Kansas. Low temperatures this morning will range from the low to upper 30s after all of the precipitation has exited the region. Drier mid level air will began to filter in today from the northwest although lower levels will be slower to dry out. Forecast soundings show that cold air advection will prevent drying and low level RH remains high in the form of a stratus deck. Therefore the only issue today will be how fast the clouds can clear or scatter out of the area. As of now it appears clearing will begin in north central Kansas during mid morning. The clearing should reach far northeast Kansas in the early afternoon hours. Northwest winds will also decrease from west to east through out the day although the eastern half of the CWA will remain gusty until around sunset. High temperatures stay in the upper 40s in the northeast CWA while southwest portions reach the low 50s. Later tonight high pressure builds into the central plains leaving skies clear and winds light. Low temperatures tomorrow morning drop into the upper 20s to low 30s. .LONG TERM...(Thursday through Tuesday) Issued at 318 AM CST WED NOV 6 2013 Thursday through Sunday night, the mid and upper level flow will become zonal. An upper level trough will move east across the northern plains on Friday. The stronger ascent ahead of this wave will remain well northeast of the CWA along with any precip chances. Highs Thursday will warm into the mid to upper 50s. The increasing westerly mid level flow across the central Rockies will cause a lees surface trough to deepen Friday. The resulting pressure gradient across central KS will cause southerly winds to increase to 20 to 30 MPH with some gusts to 40 MPH Friday afternoon. The southerly winds may reach near wind advisory criteria across the western CWA Friday afternoon. Given drier vegetation and gusty southerly winds, there will be a very high fire danger. The southerly winds will help high temperatures to warm into the lower to mid 60s. As the upper level trough moves east across the Great Lakes States Friday night, a cold front will move southward across the CWA Saturday morning. The airmass behind the front will only be slightly cooler. Highs Saturday will reach around 60, with mid to upper 50s on Sunday. Monday through Tuesday, the weak cold front will stall out across central OK and begin to move north as a warm front. Deeper moisture advection and isentropic lift will cause clouds and a slight chance for showers Monday night into Tuesday. Highs will reach the mid to upper 50s on Monday, with lower to mid 50s on Tuesday. && .AVIATION...(For the 18Z TAFs through 18Z Thursday Afternoon) Issued at 1135 AM CST WED NOV 6 2013 RAP and HRRR solutions show the low level saturation hanging on through much of the afternoon. With satellite imagery showing a decent STRATOCU deck extending upstream into NEB, will hang onto MVFR CIGS until the late afternoon. Am a little concerned for some shallow ground fog developing late tonight. The main hiccup in fog formation is the models indicating a weak surface trough moving through northeast KS overnight implying some mixing could occur. But if skies clear out and the boundary layer decouples it may not matter that a trough propagates through the area. Therefore think the chances for ground fog within the KS river valley are high enough to include a mention in the TOP and MHK terminals. && .TOP WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SHORT TERM...Sanders LONG TERM...Gargan AVIATION...Wolters
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
401 PM EST WED NOV 6 2013 .SHORT TERM...(THIS EVENING THROUGH THURSDAY) ISSUED AT 400 PM EST WED NOV 6 2013 WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL TROUGH FROM HUDSON BAY THROUGH THE WRN GREAT LAKES TO THE SRN PLAINS. PCPN ASSOCIATED WITH 800-600 MB FGEN AND DEEP LAYER QVECTOR CONV AHEAD OF THE SHRTWV THROUGH CNTRL UPPER MI WAS QUICKLY EXITING THE CWA INTO FAR ERN UPPER MI. 850 MB TEMPS TO AROUND -7C(LAKE TEMPS NEAR 8C) ONLY PROVIDED MARGINAL INSTABILITY FOR ANY LAKE EFFECT PCPN WITH SUBSIDENCE PREVAILING IN THE WAKE OF THE SHRTWV. RADAR INDICATED ONLY ISOLATED FLURRIES/SPRINKLES INTO WEST UPPER MI AND S CNTRL LAKE SUPERIOR. TONIGHT...CAA DROPPING 850/700 MB TEMPS TO -9C/-15C AND GRADUALLY CLIMBING INVERSION HEIGHTS WILL FAVOR INCREASE IN LES FOR WNW FLOW SNOWBELTS. HOWEVER...ONLY MINOR ACCUMULATIONS OF AN INCH OR LESS ARE EXPECTED FOR HIGHER TERRAIN LOCATIONS IN THE WEST NORTH OF M-28 AND OVER THE EAST FROM MUNISING AND SHINGLETON EASTWARD. THURSDAY...300-310 LOW LEVEL FLOW LES WILL CONTINUE AND MAY INCREASE ESPECIALLY OVER THE EAST HALF AS A WEAK 850-700 MB TROUGH BRUSHES THE ERN LAKE WITH CLIMBING INVERSION HEIGHTS(AN INCREASE IN 850-700 MB MOISTURE AND 700 MB TEMPS TO NEAR -18C). EVEN WITH NMRS SHSN...EXPECT ONLY LIGHT ACCUMULATIONS OF AN INCH OR LESS AND A RAIN/SNOW MIX AS SFC TEMPS CLIMB INTO THE MID TO UPPER 30S BY AFTERNOON. OVER THE WEST...SOME LIGHT ACCUMULATIONS MAY ALSO BE POSSIBLE BUT WILL BE LIMITED BY THE SHORTER FETCH LENGTH AND LESS FAVORABLE LOW LEVEL CONVERGENCE. .LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 400 PM EST WED NOV 6 2013 FOR THU NIGHT WILL INITIALLY SEE SLIGHTLY CYCLONIC NW WINDS ACROSS LAKE SUPERIOR AS A WEAK SHORTWAVE WILL BE OVER THE ERN CWA...BUT WINDS WILL BECOME INCREASINGLY ANTICYCLONIC THROUGH THE NIGHT AS A SFC RIDGE MOVES TO THE FAR WRN CWA BY 12Z FRI. 850MB TEMPS WILL GENERALLY STAY AROUND -8C TO -9C...SO LES IN NORTHWEST WIND SNOWBELTS IS EXPECTED...ESPECIALLY OVER ERN UPPER MI WHERE THE LONGER FETCH AND LONGER LASTING LOW LEVEL MOISTURE AND FAVORABLE LOW LEVEL FLOW WILL BE. SNOWFALL AMOUNTS LOOK RELATIVELY MINOR...BUT SHOULD BE GREATEST OVER THE NERN CWA WHERE A COUPLE OF INCHES ARE POSSIBLE. THE SFC RIDGE AXIS WILL BE E OF THE CWA BY 00Z SAT...CONFINING ANY REMAINING ISOLATED LES TO NEAR WHITEFISH POINT BY FRI EVENING. SOME PRECIP MAY BE MOVING INTO THE FAR WRN CWA BY 00Z SAT AHEAD OF A SHORTWAVE THAT THE 12/06 GFS AND 00Z/06 ECMWF SHOW MOVING FROM ERN SD AT 00Z SAT TO NRN LAKE MICHIGAN AT 12Z SAT THEN TO ONTARIO E OF LAKE HURON BY 18Z SAT. AT THE SAME TIME...A MORE SUBSTANTIAL SHORTWAVE WILL MOVE OVER THE SRN MANITOBA/ONTARIO BORDER. AHEAD OF THE STRONGER SHORTWAVE IS WHERE THE SFC LOW WILL ORGANIZE...WITH A SFC TROUGH EXTENDING SE TO THE WEAKER SHORTWAVE. STILL SOME MODEL DISAGREEMENT ON THE STRENGTH/TRACK OF THE SHORTWAVES /MAINLY THE WEAKER ONE/ SO CONFIDENCE IS SOMEWHAT LIMITED. DO AGREE WITH PREVIOUS FORECASTER THAT LIKELY POPS ARE JUSTIFIED...SINCE MAIN LACK OF CONFIDENCE IS WITH PTYPE AND EXACT AMOUNTS OF PRECIP. PTYPES LOOK TO BE MOSTLY SNOW OVER THE WRN CWA /WITH SOME RAIN MIXED IN/ TO MOSTLY RAIN OVER THE ERN CWA DUE TO WARMER AIR COMING OFF LAKE MICHIGAN. EVEN THOUGH LOW LEVEL TEMPS WILL INITIALLY BE WARM...THE WARM LAYER WILL ALSO BE DRY SO WET BULB TEMPS WILL BE SIGNIFICANTLY LOWER. LOOKS AS THOUGH MOST SYNOPTIC PRECIP WILL BE DONE BY 00Z SUN. THINK THAT UP TO 2 INCHES OF SNOW IS POSSIBLE OVER THE WRN CWA...BUT STILL FAIRLY UNCERTAIN ON THAT NUMBER. AFTER THE TROUGH/COLD FRONT MOVES THROUGH SAT...LOW LEVEL AIR COLD ENOUGH FOR LES WILL MOVE IN THROUGH AT LEAST SAT NIGHT /MODEL SOLUTIONS DIVERGE SIGNIFICANTLY AFTER THAT SO ENDING TIME IS VERY UNCERTAIN/. THINK IT WILL BE A FAIRLY QUICK SHOT OF THE BEST CONDITIONS AS FLOW BECOMES MORE ANTICYCLONIC THROUGH SAT NIGHT...SO ACCUMULATIONS SHOULD BE FAIRLY MINOR. SUN THROUGH NEXT WED IS VERY UNCERTAIN AS MODELS SHOW SIGNIFICANT RUN TO RUN AND MODEL TO MODEL DISAGREEMENT WITH DETAILS OF UPPER LEVEL ENERGY. ONE THING THAT DOES LOOK MORE CERTAIN IS THE ARRIVAL OF MUCH COLDER TEMPS. THE ECMWF IS THE COLDER THAN THE GFS IN BRINGING 850MB TEMPS OF -15C TO -20C OVER THE CWA FROM MON NIGHT THROUGH NEXT WED. THE GFS IS COLD AS WELL...BUT NOT AS COLD AS THE ECMWF...SHOWING 850MB TEMPS OF -10C TO -15C FROM SUN NIGHT THROUGH NEXT WED. OF COURSE...LES WOULD OCCUR IN THIS SCENARIO DEPENDING ON WIND DIRECTION...WHICH IS VERY UNCERTAIN...AND SYNOPTIC SNOWFALL WOULD ALSO LIKELY OCCUR AT SOME POINT...BUT THIS IS EVEN MORE UNCERTAIN. WILL GO WITH GENERAL CONSENSUS OF MODEL GUIDANCE RIGHT NOW...BUT WILL INCREASE POPS TO AT LEAST CHANCE FOR LES MON NIGHT INTO TUE. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON) ISSUED AT 102 PM EST WED NOV 6 2013 MVFR CIGSS EARLY THIS AFTERNOON ARE EXPECTED TO IMPROVE TO VFR BY 20Z-23Z...HOLDING OUT LONGEST AT CMX...AS MUCH DRIER AIR MOVES IN FROM THE WEST. GUSTY NORTHWEST WINDS WILL ALSO DIMINISH THIS EVENING AS HIGH PRES BUILDS TOWARD THE REGION && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 400 PM EST WED NOV 6 2013 LOW PRESSURE OVER NRN LAKE HURON WILL QUICKLY EXIT INTO QUEBEC THIS EVENING...LEAVING A TROUGH ACROSS LAKE SUPERIOR THROUGH EARLY THURSDAY. HIGH PRESSURE ACROSS MUCH OF THE CENTRAL PORTIONS OF THE NATION WILL TRACK EASTWARD ACROSS THE MISSISSIPPI VALLEY THURSDAY NIGHT AND FRIDAY...PUSHING A RIDGE OVER LAKE SUPERIOR. LOOK FOR LOW PRESSURE OVER THE NORTHERN AND CENTRAL PLAINS ON FRIDAY TO CROSS ONTARIO SATURDAY AND SATURDAY NIGHT...PUSHING A TROUGH OVER LAKE SUPERIOR ON SATURDAY. WHILE THE LOW DEEPENS OVER HUDSON BAY...HIGH PRESSURE ACROSS THE NORTHERN AND CENTRAL PLAINS SATURDAY NIGHT WILL SLOWLY MOVE ACROSS THE UPPER GREAT LAKES ON SUNDAY. EXPECT INCREASED NW WINDS SATURDAY NIGHT INTO SUNDAY...WITH GALES OF 35 TO 40KTS. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLB LONG TERM...TITUS AVIATION... MARINE...JLB
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
348 PM CST WED NOV 6 2013 .SHORT TERM...(THIS EVENING THROUGH THURSDAY) ISSUED AT 347 PM CST WED NOV 6 2013 MOST INTERESTING THING WITH THE WEATHER TO MONITOR TODAY IS THE SHRINKING OF THE SNOWPACK LEFT OVER FROM LAST NIGHTS SNOW ON VISIBLE SATELLITE. AS WE GET INTO THE BACK SIDE OF THE TROUGH THAT BROUGHT US THIS SNOW...WE ARE SEEING OUR FLOW ALOFT TURN NW. WITH THE NW FLOW COMES SOME WEAK MID LEVEL SHORTWAVE ENERGY THAT IS DROPPING SOME CLOUD COVER DOWN ACROSS CENTRAL MN THIS AFTERNOON. OF MORE CONCERN THOUGH ARE THE LOW CLOUDS ACROSS SE SODAK. THESE CLOUDS HAVE BEEN DIMINISHING DURING THE DAY...BUT WITH THEM NOW MOVING OVER THE SNOWPACK...THE DECREASED MIXING THERE WILL LIKELY MEAN WE DO NOT COMPLETELY LOSE THEM BEFORE THE SUNSETS...SO WILL PROBABLY HAVE THEM EXPAND IN ONE FASHION OR ANOTHER TONIGHT. THE HRRR MAY BE A LITTLE AGGRESSIVE...BUT DOES SHOW THESE CLOUDS EXPANDING ACROSS MUCH OF SOUTHERN MN TONIGHT. HAVE DOWNPLAYED THE FOG POTENTIAL SOME TONIGHT AS MODELS SHOW ENOUGH OF A GRADIENT REMAINING TONIGHT TO KEEP WINDS UP AROUND 5 KTS FOR ALL BUT CENTRAL MN...WHICH SHOULD KEEP THINGS MORE OF A STRATUS THAN A FOG CONCERN. ONLY LEFT SOME PATCHY FOG OVER THE SW CWA...MORE OR LESS WHERE THE DEEPER SNOWPACK EXISTS. .LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 347 PM CST WED NOV 6 2013 THERE ARE TWO CHANCES FOR PRECIP IN THE EXTENDED. THE FIRST ON FRIDAY WILL BRING MAINLY RAIN ACROSS THE REGION. THE SECOND WILL BE MONDAY INTO MONDAY NIGHT...AND THIS WILL BE MAINLY A SNOW EVENT. EARLY AFTERNOON WATER VAPOR IMAGERY AND GFS 500MB HEIGHTS AND WINDS SHOWED A TROUGH OFF THE BRITISH COLUMBIA COAST. A SHORTWAVE WITHIN THIS TROUGH WILL MOVE ACROSS THE MOUNTAIN WEST ON THURSDAY. H850 THETA_E ADVECTION WILL OVERSPREAD THE REGION ON FRIDAY...AND TOGETHER WITH THE UPPER LEVEL DYNAMICS OF THIS SYSTEM WILL DEVELOP PRECIP ACROSS THE UPPER MISSISSIPPI RIVER VALLEY. FORECAST SOUNDINGS STRUGGLE TO SATURATE THE LOWER LEVELS...BUT BASED ON THE FORCING CONFIDENCE IS HIGH IN MEASURABLE PRECIP...ESPECIALLY NORTH OF I-94. THIS FAST MOVING SYSTEM WILL EXIT THE REGION BY SATURDAY...WITH HIGH PRESSURE BUILDING IN FOR THE WEEKEND. HOWEVER...ANOTHER SHORTWAVE WILL MOVE ACROSS THE REGION EARLY NEXT WEEK AND BRING CHANCES FOR SNOW FOR MONDAY AND TUESDAY. AT THIS TIME ONLY HAVE CHANCE POPS...BUT THE MODELS CONTINUE TO SHOW CONSISTENCY...WITH POTENTIAL FOR A FEW INCHES OF SNOW BY THE TIME IT MOVES OFF LATE THURSDAY. IF THIS TREND CONTINUES EXPECT THE POPS TO INCREASE ALONG WITH && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON) ISSUED AT 1147 AM CST WED NOV 6 2013 TWO ISSUES THIS TAF PERIOD REVOLVE AROUND 5K-7K FT CLOUDS CURRENTLY MOVING INTO NW MN AND REMNANT IFR CIGS OVER SE SODAK. FLOW BETWEEN 5K AND 7K FT WILL BRING THOSE CLOUDS SE INTO THE MPX AREA...WHILE LOW LEVEL FLOW OUT OF THE WEST WILL BRING LOW LEVEL MOISTURE INTO SRN MN BY TONIGHT. CURRENTLY FAVOR THE IDEA OF THE RAP...WHICH HAS THE BKN TO OVC 5K-7K FT CLOUDS WORKING ABOUT AS FAR SW AS THE MN RIVER AND STAYING IN PLACE THROUGH MOST OF THE NIGHT. SOUTH OF THESE CLOUDS WILL BE THE POTENTIAL FOR IFR/LIFR STRATUS TO FORM...WITH RWF HAVING THE BEST POTENTIAL FOR SEEING THESE CLOUDS...ESPECIALLY GIVEN THE SNOW COVER IN PLACE. SHOULD BE MAINLY A STRATUS ISSUE TONIGHT...AS GRADIENT LOOKS STRONG ENOUGH TO MAINTAIN 5 KT WNW WINDS...WHICH SHOULD BE ENOUGH TO KEEP DENSE FOG FROM FORMING ANYWHERE IN THE MPX AREA. KMSP...BIGGEST QUESTION MARK FOR TAF REVOLVES AROUND CLOUDS CURRENTLY NORTHWEST OF THE FIELD THAT WILL BE HEADING THIS DIRECTION THIS AFTERNOON. MAIN QUESTION WITH THEM IS HOW LONG DO THEY HANG AROUND. NAM INDICATES THAT ONCE THEY MOVE IN...THEY ARE WITH US THROUGH THE REST OF THE TAF. IF THAT HAPPENS...THEN STRATUS/FOG WILL NOT BE AN ISSUE TONIGHT. WITH THAT CLOUD UNCERTAINTY...REMOVED THE MVFR VIS WE HAD GOING THU MORNING. /OUTLOOK FOR KMSP/ FRI...CHC FOR MVFR CIGS AND -RA. WINDS SE 15G25 KTS. SAT...VFR. WINDS W 10-15 KTS. SUN...VFR. WINDS BCMG S 5 KTS. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. && $$ SHORT TERM...MPG LONG TERM...JRB AVIATION...MPG
AREA FORECAST DISCUSSION
NWS HASTINGS NE
243 PM CST WED NOV 6 2013 .SHORT TERM...(THIS EVENING THROUGH THURSDAY) ISSUED AT 242 PM CST WED NOV 6 2013 THE SHORT TERM PERIODS WILL CONTINUE TO FEATURE QUIET/DRY WEATHER CONDITIONS. STRATUS HAS BEEN SLOW TO ERODE ACROSS THE EASTERN THIRD OF OUR CWA EARLY THIS AFTN...HOLDING TEMPERATURES IN THE MID/UPPER 30S...WHILE TO THE WEST IN INSOLATION...TEMPS HAVE CLIMBED INTO THE 40S. THE LOW CLOUDS WILL CONTINUE TO DISSIPATE TODAY...WITH AN INCREASE IN SCATTERED MID/HIGH CLOUDS INTO THURSDAY. A SUBTLE SFC TROUGH WILL CROSS OUR REGION THIS EVENING AS ENERGY TRANSLATES ACROSS THE UPPER MIDWEST REGION...BEHIND THE TROUGH SFC HIGH PRESSURE WILL WEAKEN AS IT BUILDS EAST OF THE ROCKIES AND SETTLES ON TO THE PLAINS FOR THURSDAY. OF NOTE IS THAT THE SREF IS INDICATING SOME POTENTIAL FOR FOG DEVELOPMENT TONIGHT...BUT THIS IS NOT SUPPORTED BY THE RAP OR OTHER SHORT TERM MODELS ATTM. HAVE NOT INCLUDED ANY MENTION IN FCST WITH WESTERLY WIND COMPONENT...VERY LITTLE SNOWPACK ACROSS OUR CWA AND COLD/SUB FREEZING TEMPS FORECAST FOR LOWS TONIGHT. THIS BEING SAID...IT IS SOMETHING TO KEEP AN EYE ON AS WE HEAD INTO TONIGHT. THURSDAY WILL FEATURE MILDER TEMPS WITH DAYTIME READINGS EDGING CLOSER TO SEASONAL NORMALS WITH HIGHS IN THE LOW/MID 50S. WINDS WILL BE FAIRLY LIGHT WITH SFC RIDGE IN PLACE. .LONG TERM...(THURSDAY EVENING THROUGH WEDNESDAY) ISSUED AT 242 PM CST WED NOV 6 2013 IN TERMS OF FORECAST CONFIDENCE IN BASIC ELEMENTS SUCH AS TEMPERATURES/POPS...THIS 6-DAY PERIOD IS CURRENTLY A SPLIT DECISION...FEATURING RATHER HIGH CONFIDENCE IN DRY AND SEASONABLY WARM WEATHER THROUGH THE WEEKEND...BUT THEN CONSIDERABLY LOWER CONFIDENCE ESPECIALLY REGARDING TEMPERATURES DURING THE MON-WED TIME FRAME. AT ANY RATE...THE ONLY PERIODS CURRENTLY FEATURING ONLY SLIGHT...STILL-HIGHLY UNCERTAIN CHANCES OF PRECIP ARE TUESDAY IN THE EAST/SOUTH AND THEN WEDNESDAY ALL AREAS. GETTING INTO GREATER DETAIL AND STARTING WITH THURSDAY EVENING/NIGHT...UPPER FORCING REMAINS NEGLIGIBLE LOCALLY AS THE AREA LIES IN BETWEEN A NORTHEAST CONUS LARGE-SCALE TROUGH AND AN UPSTREAM SHORTWAVE TROUGH CROSSING THE NORTHERN ROCKIES. HOWEVER...AM EXPECTING A FAIR AMOUNT OF PASSING MID-HIGH LEVEL CLOUDS. AT THE SURFACE...THE EFFECT OF THE UPSTREAM DISTURBANCE WILL BE HIGH PLAINS PRESSURE FALLS...WHICH WILL INDUCE A GRADUALLY INCREASING SOUTHERLY WIND AS THE NIGHT WEARS ON...WITH MOST AREAS 10+ MPH AFTER MIDNIGHT. THE PASSING CLOUDS AND BREEZES SHOULD KEEP TEMPS FROM FALLING TOO SHARPLY...AND KEPT LOWS A FEW DEGREES ABOVE A BLEND OF 12Z MET/MAV GUIDANCE BUT DID NUDGE DOWN SLIGHTLY FROM PREVIOUS FORECAST...AIMING MOST PLACES BETWEEN 32-35 AND SOME UPPER 20S IN THE VALLEY/GREELEY/WESTERN DAWSON COUNTY AREA. ALTHOUGH AM NOT EXPECTING MAJOR ISSUES WITH FOG DEVELOPMENT THANKS TO INCREASING BREEZES...WILL HAVE TO KEEP AN EYE ON FAR NORTHERN AREAS WHERE SNOW MELT WILL BE ONGOING BETWEEN NOW AND THEN. FRIDAY/FRIDAY NIGHT...INCREASED SKY COVER PERCENTAGES FOR THE DAYTIME HOURS...AND MAYBE NOT ENOUGH...AS AGAIN EXPECT PLENTY OF PASSING MID-HIGH LEVEL CLOUDS ALONG THE SOUTHERN PERIPHERY OF THE QUICK-MOVING SHORTWAVE TROUGH WILL TRACK FROM THE MT/WY AREA ON SUNRISE FRIDAY...ALL THE WAY TO LAKE MICHIGAN BY SUNRISE SATURDAY. AT THE SURFACE...THE DAYTIME HOURS CONTINUE TO LOOK RATHER BREEZY ACROSS MAINLY THE SOUTHEAST HALF OF THE CWA...WITH SUSTAINED SOUTH-SOUTHWEST SPEEDS AROUND 20 MPH GUSTING TO AROUND 30 MPH...WHILE WESTERN AREAS WILL REMAIN GENERALLY 5-10 MPH LIGHTER IN CLOSER PROXIMITY TO A SURFACE TROUGH. FORTUNATELY FOR FIRE WEATHER CONCERNS...EVEN IN THE WINDIER SOUTHEAST RELATIVE HUMIDITY VALUES ARE FORECAST TO HOLD UP IN THE 25-30 PERCENT RANGE...OR 5-10 PERCENT ABOVE CRITICAL LEVELS. TEMP-WISE...DESPITE HIGH CLOUDS EXPECT A NICE UPWARD BUMP FROM THURSDAY HIGHS. HAVE AIMED MOST OF THE CWA INTO THE UPPER 50S-LOWER 60S RANGE...WITH MID 60S MOST FAVORED IN KS ZONES AND THE DAWSON-FURNAS CORRIDOR IN THE WEST. IN THESE WESTERN ZONES THIS IS ABOUT A 5-DEGREE UPWARD BUMP FROM PREVIOUS FORECAST. ON FRI NIGHT...A VERY WEAK COLD FRONT NUDGES INTO THE THE CWA...SIGNALED BY LITTLE MORE THAN A SHIFT TO FAIRLY LIGHT NORTHERLY BREEZES. AGAIN...SUPPOSE SOME FOG DEVELOPMENT CANNOT BE RULED OUT ESPECIALLY IN NORTHERN AREAS DUE TO CONTRIBUTION FROM MELTED SNOW...BUT AT THIS TIME BELIEVE VISIBILITY PRODUCT FORECASTS FROM THE NAM/SREF ARE OVER-DOING THINGS...AND WILL LEAVE THE FORECAST FOG-FREE FOR NOW. CHANGED FRIDAY NIGHT LOWS LITTLE WITH MOST PLACES MID-30S. SATURDAY DAYTIME THROUGH SUNDAY NIGHT...DRY WEATHER PERSISTS WITH GENERALLY SUNNIER CONDITIONS COMPARED TO FRIDAY. IN THE MID-UPPER LEVELS...LOW AMPLITUDE RIDGING WILL DOMINATE MUCH OF THE CENTRAL/WESTERN CONUS AS THE PRIMARY UPPER JET CORE AND ASSOCIATED TRACK OF SHORTWAVE TROUGHS REMAINS WELL TO THE NORTH ALONG THE U.S./CANADA BORDER. ON SATURDAY...BREEZES WILL AVERAGE ONLY AROUND 10 MPH FROM THE NORTH...AND THEN TURNING SOUTHERLY AGAIN FOR SUNDAY. MADE LITTLE CHANGE TO TEMPS...WITH SATURDAY HIGHS RANGING FROM LOW 50S FAR NORTH TO NEAR 60 SOUTH...AND SUNDAY MID-UPPER 50S AREA-WIDE. MONDAY-WEDNESDAY OF NEXT WEEK...CONFIDENCE IN FORECAST DETAILS STEADILY DECREASES ALTHOUGH THAT BEING SAID...NO MAJOR PRECIPITATION EVENTS APPEAR IN STORE. MONDAY-MONDAY NIGHT...THE OFFICIAL FORECAST REMAINS DRY. IN THE MID-UPPER LEVELS...FLOW TURNS MORE NORTHWESTERLY IN RESPONSE TO A BUILDING WESTERN CONUS RIDGE. TEMPS ARE THE BIG QUESTION MARK. ALTHOUGH THE DEFAULT MULTI-MODEL BLEND HAS PROVIDED WIDESPREAD 50S FOR HIGHS IN MOST AREAS TO THE OFFICIAL FORECAST...THE LATEST ECMWF SOLUTION PROVIDES A STRONGER COLD FRONTAL PUSH...WITH HIGHS ABOUT 5-10 DEGREES COLDER MAINLY IN THE 40S. THERE ARE ALSO HINTS OF SOME LOW STRATUS...WHICH COULD RESULT IN SOME NUISANCE LIGHT DRIZZLE...SO THIS BEARS WATCHING. GETTING INTO TUESDAY/TUESDAY NIGHT...THE 12Z ECMWF/GFS ARE IN SURPRISINGLY GOOD AGREEMENT REGARDING A SHORTWAVE TROUGH DIVING SOUTHEAST OVER THE LOCAL AREA ALONG A TRACK FROM THE NORTHERN ROCKIES/NORTHERN PLAINS TO EASTERN KS/MO. HOWEVER...THE BULK OF PRECIPITATION WITH THIS WAVE IS CURRENTLY SLATED TO PASS JUST EAST AND/OR SOUTH OF THE CWA. ALTHOUGH SOME GENERALLY LIGHT...NUISANCE PRECIP POSSIBLY IN THE FORM OF DRIZZLE COULD OCCUR ALMOST ANYWHERE DURING THIS TIME...STUCK WITH THE INITIALIZED BLENDED FORECAST FOR NOW...WHICH KEEPS LIGHT RAIN ONLY IN FAR EASTERN ZONES DURING THE DAY...AND THEN NO MENTION OF PRECIP TUESDAY NIGHT. TEMP-WISE TUESDAY...AGAIN LOW CONFIDENCE REGARDING HIGHS...AS THE OFFICIAL FORECAST IS MID 40S TO MID 50S...WHILE THE LATEST ECMWF CAME IN 5-10 DEGREES COLDER THAN THIS. FOR WEDNESDAY DAYTIME...HAVE A SLIGHT CHANCE OF RAIN OR RAIN/SNOW IN ALL AREAS...BUT THIS WAS LARGELY BASED OFF THE 00Z ECMWF...AND ITS WORTH NOTING THAT THE LATEST RUN HAS COME IN DRY AS THE AFOREMENTIONED SHORTWAVE TROUGH TAKES THE MAJORITY OF FORCING SOUTHEAST OF THE AREA WITH IT. THERE IS DECENT CONFIDENCE THAT TEMPS WEDNESDAY WILL TAKE A COLDER TURN...ITS JUST A MATTER OF HOW MUCH SO. THE OFFICIAL FORECAST AIMS FOR A MID 30S-LOW 40S RANGE IN MOST SPOTS...BUT THE LATEST ECMWF IS COLDER WITH MID 30S MOST ALL PLACES. PLENTY TO SORT OUT HERE IN THE DAY 5-7 PERIOD. && .AVIATION...(FOR THE 18Z KGRI TAF THROUGH 18Z THURSDAY AFTERNOON) ISSUED AT 1115 AM CST WED NOV 6 2013 BORDERLINE IFR TO MVFR CLOUDS WILL DEPART THE TERMINAL IN THE NEXT COUPLE OF HOURS. CLOUDS THEREAFTER WILL BE AT VFR LEVELS. LOOK FOR WINDS TO REMAIN FROM A WESTERLY TO NORTHWESTERLY DIRECTION. && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$ SHORT TERM...FAY LONG TERM...PFANNKUCH AVIATION...FAY
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
317 PM EST WED NOV 6 2013 .SYNOPSIS... A TROUGH PUSHING WEST TOWARD THE COAST WILL PRODUCE SOME RAIN OVER THE COASTAL CAROLINAS TONIGHT. A COLD FRONT WILL MOVE THROUGH ON THURSDAY CLEARING OUT ALL OF THE CLOUDS AND SHOWERS AND BRINGING COOLER WEATHER FOR FRIDAY. HIGH PRESSURE WILL BUILD IN THROUGH THE WEEKEND MAINTAINING DRIER AND MORE SEASONABLE WEATHER INTO EARLY NEXT WEEK. && .NEAR TERM /THROUGH TONIGHT/... AS OF 300 PM WEDNESDAY...A WONDERFUL EARLY NOVEMBER DAY IN THE CAROLINAS WILL CHANGE TONIGHT AS A HORIZONTALLY-CONVERGENT AND VERTICALLY-ASCENDING FLOW DEVELOPS NEAR A COASTAL TROUGH MOVING TOWARD THE CAROLINA COAST. THIS TROUGH...EASILY DISCERNIBLE ON VISIBLE SATELLITE IMAGERY EXTENDING ALONG THE WESTERN EDGE OF THE GULF STREAM...IS EXPECTED TO APPROACH THE COAST BY MIDNIGHT AND MAY ACTUALLY PUSH ONSHORE IN SOUTHEASTERN NORTH CAROLINA. MILD ATLANTIC AIR STREAMING UP AND OVER THE WARM FRONT-LIKE BOUNDARY WILL BE LIFTED ALONG THE 300-305K ISENTROPIC SURFACES...LIKELY YIELDING AROUND ONE-THIRD INCH OF SHOWERY RAIN FROM MYRTLE BEACH... SOUTHPORT AND WILMINGTON THROUGH WHITEVILLE AND ELIZABETHTOWN. ONE OR TWO TENTHS OF AN INCH OF RAIN IS EXPECTED FROM GEORGETOWN AND MARION THROUGH DILLON AND LUMBERTON. FARTHER INLAND FOR AREAS WEST OF FLORENCE...THE ATLANTIC MOISTURE FEED MAY HAVE TROUBLE REACHING YOU AS VEERING WIND PROFILES BELOW 700 MB COULD CREATE A WESTERLY COMPONENT WITHIN THE CLOUD-BEARING LAYER BEFORE THE ATLANTIC MOISTURE IS ABLE TO PUSH THAT FAR INLAND. I HAVE LOWER RAIN CHANCES HERE ONLY IN THE 20-30 PERCENT RANGE. IN TERMS OF MODEL PREFERENCE...THE 12Z GFS LOOKS PRETTY GOOD AS DO THE LATEST SEVERAL RUC AND HRRR RUNS. THE 12Z NAM REALLY EMPHASES LOW PRESSURE ALONG THE SOUTHERN END OF THE COASTAL TROUGH JUST OFF THE FLORIDA COAST. WHILE SATELLITE LOOPS SUGGEST THERE A WEAK LOW ABOUT 200 MILES EAST OF JAX...THE NAM APPEARS TO BE TOO BULLISH CLOSING THIS FEATURE OFF ALONG THE GEORGIA COAST OVERNIGHT. THE NAM IS ALSO THE FARTHEST WEST WITH ITS QPF MAX COMPARED TO OTHER GUIDANCE. CLOUDS SHOULD HELP HOLD TEMPERATURES WELL ABOVE NORMAL TONIGHT WITH FORECAST LOWS RANGING FROM THE LOWER 60S AT THE COAST TO THE UPPER 50S INLAND. KEEP IN MIND OUR CLIMATOLOGICAL NORMALS FOR LOWS HAVE FALLEN TO THE MID TO UPPER 40S THIS LATE IN THE YEAR. && .SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... AS OF 300 PM WEDNESDAY...COASTAL TROUGH RIGHT ALONG THE CAPE FEAR COAST THURS MORNING WILL OPEN UP AND DISSIPATE AS COLD FRONT PUSHES EAST ACROSS THE FORECAST AREA ON THURS. THE SOUTHERLY RETURN FLOW WILL PUMP A GOOD DEAL OF ATLANTIC MOISTURE NORTHWARD THROUGH EARLY THURS. THE BEST CONVERGENCE AND MOISTURE WILL RUN NORTH FROM THE BRUNSWICK AND CAPE FEAR COAST UP THROUGH NORTH CAROLINA. THE NAM SHOWS A DEEPER TROUGH AND PUSHES IT INLAND FURTHER SO MAY KEEP POPS SLIGHTLY FARTHER INLAND FOR NOW. THIS AXIS OF GREATEST PCP THURS MORNING WILL SHIFT EAST AND OFF SHORE BY THURS AFTN AS WINDS VEER AROUND TO THE WEST TO NORTHWEST AS COLD FRONT PROGRESSES THROUGH THE CAROLINAS. THE ACTUAL COLD FRONT LOSES SOME OF ITS MOISTURE AS IT MOVES OVER THE APPALACHIANS THURS MORNING BUT IT SHOULD HELP TO ENHANCE THE CONVERGENCE AHEAD AND ALONG THE FRONT THURS AFTN. AS MENTIONED...LOOKS LIKE GREATEST PCP WILL COME EARLIER IN THE DAY WITH TROUGH ALONG THE COAST...BUT EXPECT SOME CONVECTIVE DEVELOPMENT JUST ALONG AND AHEAD OF FRONT THROUGH LATE THURS AFTN. DEEP COOL AND DRY NORTHWEST TO NORTHERLY FLOW WILL DEVELOP BEHIND THE FRONT THROUGH THURS EVENING INTO FRIDAY. 850 TEMPS BEGIN TO PLUMMET THURS AFTN DROPPING FROM AROUND 13C DOWN TO 3C TO 4C BY FRI MORNING. PCP WATER VALUES UP TO 1.5 INCHES AHEAD OF THE FRONT WILL DROP OUT TO A QUARTER OF INCH ON FRIDAY. TEMPS WILL DROP INTO THE 40S FRI NIGHT IN CAA BEHIND FRONT. THE TIGHTENED GRADIENT WILL PRODUCE COOLER BLUSTERY CONDITIONS FOR THE CAROLINAS ON FRIDAY BUT THE NORTHERLY WINDS WILL DIMINISH AS HIGH PRESSURE BUILDS EAST THROUGH FRI EVENING. HIGH TEMPS ON FRI WILL MAKE IT TO AROUND 60 IN CONTINUED CAA UNDER BRIGHT FALL SUNSHINE. BETTER RADIATIONAL COOLING CONDITIONS WILL EXIST THROUGH FRI EVENING AS WINDS DROP OFF AND CLEAR SKIES EXIST. EXPECT TEMPS TO DROP INTO THE 30S MOST PLACES FRI NIGHT. && .LONG TERM /SATURDAY THROUGH WEDNESDAY/... AS OF 300 PM WEDNESDAY...DRY AND SEASONABLE WEATHER FOR THE EXTENDED THANKS TO A COMBINATION OF FLAT 5H FLOW AND SURFACE HIGH PRESSURE PERSISTING ACROSS THE EAST. NEARLY ZONAL FLOW ALOFT WILL KEEP THE COLD AIR WELL NORTH OF THE AREA...BUT ALLOW REINFORCING AREAS OF HIGH PRESSURE TO ADVECT WEST TO EAST FROM THE PLAINS TO THE CAROLINAS THROUGH THE PERIOD. OTHER THAN A WEAK AND DRY COLD FRONT SUNDAY NIGHT/MONDAY MORNING...VERY LITTLE IN THE WAY OF SIGNIFICANT FEATURES TO DISCUSS DURING NEXT WEEK. THIS WILL KEEP SKY CONDITIONS PRIMARILY CLEAR (ALTHOUGH SOME MID-LEVEL CLOUDINESS IS EXPECTED WITH THE FRONT SUNDAY NIGHT)...AND TEMPS NEAR SEASONABLE LEVELS. THE EXCEPTION WILL BE SATURDAY WHEN HIGHS WILL RISE ONLY INTO THE LOW/MID 60S...BUT SUN-WED WILL FEATURE HIGHS APPROACHING 70 AND LOWS IN THE 40S. A STRONGER COLD FRONT WILL APPROACH AT THE END OF THE PERIOD /WED NIGHT/ AS THE LEADING EDGE OF MUCH COOLER AIR...BUT ATTM LOOKS LIKE IT MAY ALSO BE DRY. THUS...NO PRECIP FOR THE EXTENDED. && .AVIATION /18Z WEDNESDAY THROUGH MONDAY/... AS OF 18Z...LOOK FOR INCREASING ALTOCUMULUS CEILINGS THROUGH THE LATE AFTERNOON INTO THE EVENING HOURS. THE HRRR MODEL IS ADVERTISING SOME LIGHT SHOWERS ALONG THE COAST LATE THIS AFTERNOON...ASSOCIATED WITH A WEAK COASTAL TROUGH. BY LATE THIS EVENING...MODELS IN FAIRLY GOOD AGREEMENT INTRODUCING IFR CEILINGS/VISIBILITIES CAUSED BY INCREASING COVERAGE OF MAINLY LIGHT RAIN/SHOWER ACTIVITY. THE NAM MODEL MAY BE A BIT EARLY...BUT MODERATE CONFIDENCE WE WILL SEE IFR CONDITIONS AT ALL TERMINALS AFTER 06Z. MAINLY LIGHT WINDS OVERNIGHT...EXCEPT ALONG THE COAST WHERE ONSHORE WINDS COULD REMAIN IN THE 8-10 KNOT RANGE. THURSDAY...POSSIBILITY OF SHOWERS LATE AS A SURFACE LOW RIDES NORTHWARD AHEAD OF A COLD FRONT. LOW CONFIDENCE ON WIND DIRECTION THURSDAY...DUE TO THE LOW. EXTENDED OUTLOOK...CHANCE OF SHOWERS THURSDAY AFTERNOON WITH A COLD FRONT. VFR FRIDAY THROUGH SUNDAY. MORNING FOG POSSIBLE MONDAY. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 300 PM WEDNESDAY...HIGH PRESSURE OVER THE NORTHWESTERN ATLANTIC (JUST SOUTH OF NEWFOUNDLAND) HAS MAINTAINED A HEALTHY NORTHEASTERLY WIND ACROSS THE WESTERN ATLANTIC FOR SEVERAL DAYS. THE HIGH IS BREAKING DOWN WHICH HAS CUT THE PRESSURE GRADIENT ACROSS THE ATLANTIC ALMOST IN HALF OVER THE PAST 12 HOURS. A COASTAL TROUGH CURRENTLY LINED UP NEAR THE WESTERN EDGE OF THE GULF STREAM FROM THE OUTER BANKS TO JACKSONVILLE FLORIDA SHOULD APPROACH THE COAST OVERNIGHT BEFORE STALLING AND SLOWLY DISSIPATING IN THE INCREASING SOUTHERLY FLOW AHEAD OF A COLD FRONT. A ZONE OF ENHANCED SOUTHEASTERLY FLOW JUST BEHIND OF (EAST OF) TROUGH SHOULD HELP MAINTAIN 4-6 FOOT SEAS ACROSS THE CAPE FEAR AREA WATERS TONIGHT... THEREFORE THE SMALL CRAFT ADVISORY HAS BEEN EXTENDED INTO THURSDAY MORNING. NORTHEAST WINDS WILL CONTINUE THROUGH THE EVENING...BUT SHOULD VEER MORE SOUTHEASTERLY AROUND OR AFTER MIDNIGHT AS THE COASTAL TROUGH MOVES CLOSER TO SHORE. WIND SPEEDS SHOULD AVERAGE 10-15 KNOTS EXCEPT 5 KNOTS STRONGER FOR AREAS THAT ACTUALLY GET INTO THE SOUTHEAST WINDS BEHIND THE TROUGH. SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... AS OF 300 PM WEDNESDAY...WITH TROUGH ALONG THE COAST OR JUST INLAND...WINDS WILL BE SOUTHERLY UP TO 15 KTS TO START THE DAY ON THURS. THE SOUTHERLY PUSH WILL KEEP SEAS AROUND 3 TO 6 FT INITIALLY BUT DIMINISHING QUICKLY AS WINDS VEER AROUND THROUGH THE DAY ON THURS AS COLD FRONT APPROACHES FROM THE WEST. THIS COLD FRONT WILL PROGRESS THROUGH THE CAROLINAS THURS AFTERNOON WITH WINDS VEERING AROUND TO WEST AND EVENTUALLY NORTHWEST THROUGH THURS EVENING. WINDS WILL BECOME NORTHWEST TO NORTH BEHIND FRONT AS IT MOVES EAST OF THE WATERS THURS NIGHT. PLENTY OF COOL AND DRY AIR WILL PRODUCE A WELL MIXED MARINE ENVIRONMENT AND EXPECT STRENGTHENING NORTHERLY WINDS UP TO 25 KTS WITH HIGHER GUSTS THROUGH EARLY FRI MORNING IN DEEPER CAA. THIS WILL PRODUCE AN INCREASE IN SEAS UP TO 4 TO 7 FT IN OUTER WATERS AFTER MIDNIGHT THURS NIGHT INTO EARLY FRIDAY. WINDS ALONE WILL BE ENOUGH TO WARRANT SCA LATE THU NIGHT INTO FRI MORNING...BUT SEAS WILL SHOOT UP ALSO. WINDS WILL DECREASE THROUGH LATE FRI INTO FRI NIGHT AND VEER TO NORTHEAST AS CENTER OF HIGH PRESSURE MOVES CLOSER TO THE CAROLINAS. THE DECREASE IN SPEED AND VEERING OF WINDS LATER FRI AND FRI NIGHT WILL KNOCK SEAS BACK DOWN TO 2 TO 4 FT. LONG TERM /SATURDAY THROUGH MONDAY/... AS OF 300 PM WEDNESDAY...A SERIES OF HIGH PRESSURES WILL MOVE ACROSS THE WATERS DURING THE EXTENDED...AND WINDS BEGIN THE PERIOD FROM THE NE AROUND 10 KTS BEFORE BACKING SLOWLY THROUGH SATURDAY AS A SECONDARY HIGH PRESSURE BUILDS DOWN FROM THE NW. AS THIS HIGH PRESSURE MOVES INTO THE AREA SUNDAY...IT DRIVES A DRY COLD FRONT ACROSS THE WATERS...WITH WINDS INCREASING TO AROUND 15 KTS AND TURNING BACK TO THE NE SUNDAY NIGHT. THESE NE WINDS PERSIST MONDAY...WHILE ONLY SLOWLY EASING. SEAS WILL BE WIND-DRIVEN DURING THE PERIOD...BUT THANKS TO THE LOW SPEEDS...AMPLITUDES WILL BE 1-3 FT EACH DAY...WITH A BRIEF INCREASE TO 2-4 FT LATE SUNDAY AND INTO MONDAY WITH THE FROPA. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 8 AM EST THURSDAY FOR AMZ250-252. && $$ NEAR TERM...TRA SHORT TERM...RGZ LONG TERM...JDW AVIATION...TRA/DL
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1230 PM EST WED NOV 6 2013 .SYNOPSIS... HIGH PRESSURE WILL MAINTAIN NORTHEAST WINDS ACROSS THE AREA THIS MORNING. TEMPERATURES WILL START TO WARM TODAY AS HIGH PRESSURE SHIFTS OFF THE COAST AND SOUTHERLY WINDS DEVELOP. TEMPERATURES WILL REMAIN WARM INTO THURSDAY AHEAD OF AN APPROACHING COLD FRONT. THE FRONT WILL MOVE OFF THE COAST LATE THURSDAY AND WILL BE FOLLOWED BY COOLER AND DRIER WEATHER INTO NEXT WEEK. && .NEAR TERM /THROUGH TONIGHT/... AS OF 1230 PM WEDNESDAY...TWEAKED INLAND HIGH TEMPERATURE FORECASTS UP A DEGREE OR TWO INTO THE MID 70S...OTHERWISE NO SIGNIFICANT CHANGES NEEDED. PREVIOUS DISCUSSION FROM 930 AM FOLLOWS... STRONG UPPER LEVEL HIGH PRESSURE SITS JUST OFF THE SOUTHEAST U.S. COAST...WHILE AT THE SURFACE THE HIGH IS CENTERED JUST SOUTH OF THE NEWFOUNDLAND CANADA COAST. A LONG EASTERLY FETCH AT THE SURFACE CROSSES OVER A THOUSAND MILES OF WESTERN ATLANTIC OCEAN WATER BEFORE COMING ONSHORE INTO THE CAROLINAS. PLENTY OF MOISTURE IN THE LOWEST 7500 FEET OF THE ATMOSPHERE IS PRODUCING AREAS OF EXTENSIVE ALTOCUMULUS...SOME OF WHICH ARE PRODUCING SHOWERS OFF THE COAST. ISENTROPIC LIFT ALONG THE 300K THETA SURFACE IS EXPECTED TO INCREASE BY LATE AFTERNOON IN THE CAPE FEAR REGION WITH SKIES BECOMING CLOUDY AND AN INCREASING SHOWER POTENTIAL NOTED. FARTHER INLAND THERE SHOULD BE ABOUT A 50/50 MIX OF CLOUDS AND SUN TODAY. WITH THE OVERALL AIRMASS QUITE MILD FOR THIS DATE HIGHS SHOULD REACH THE LOWER 70S DESPITE THE CLOUDS...A LITTLE ABOVE NORMAL. FOR TONIGHT I HAVE MADE SOME UPWARD CHANGES TO POPS...PARTICULARLY IN THE CAPE FEAR REGION WHERE THE LATEST HRRR AND 06Z GFS SHOW A CONCENTRATED "STREAMER" OF MOISTURE AND ISENTROPIC LIFT MOVING NORTHWARD FROM THE GULF STREAM SOUTH OF CAPE FEAR. THIS IS ACTUALLY A FAIRLY TYPICAL SCENARIO IN WEAKLY FORCED VEERING WIND SITUATIONS...AND ASSUMING 12Z MODELS CONTINUE TO SHOW THIS POTENTIAL I PLAN TO INCREASE POPS IN THE WILMINGTON AREA OVER 50 PERCENT FOR TONIGHT. FARTHER INLAND CURRENTLY POPS FOR TONIGHT ARE IN THE 20-30 PERCENT REGION AS IT APPEARS THE LIMITED DEPTH OF MOISTURE MAY NOT MAKE IT TOO FAR INLAND BEFORE THE 850-700 MB FLOW ATTAINS A BIT OF WESTERLY COMPONENT...SHUTTING DOWN ANY ATLANTIC INFLOW. 12Z MODELS SHOULD HELP REFINE THIS POTENTIAL AS WELL. && .SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... AS OF 230 AM WEDNESDAY...COLD FRONT SLATED TO MOVE ACROSS THE AREA DURING THE FIRST HALF OF THE PERIOD WILL BRING BELOW CLIMO TEMPS FOR THE END OF THE WEEK. FRONT ITSELF MAY PASS DRY WITH THE BEST PRECIP CHANCES BEING ASSOCIATED WITH A PRE-FRONTAL TROUGH PUSHING OFF THE COAST AS THE PERIOD BEGINS. BY THE TIME THE FRONT REACHES THE CAROLINAS THE 5H TROUGH WILL HAVE WEAKENED CONSIDERABLY AND THE ORIENTATION OF THE 5H RIDGE SOUTH OF THE AREA DOES NOT ALLOW FOR A SIGNIFICANT GULF MOISTURE TAP. ADDITIONALLY THE DYNAMICS ARE DISPLACED WELL NORTH OF THE AREA AND BAGGINESS IN THE GRADIENT OFF THE COAST POINTS TO DEVELOPMENT OF WEAK LOW ON THE TAIL END OF THE TROUGH...FURTHER LIMITING THE FRONTS ABILITY TO PRODUCE PRECIP. INHERITED SLIGHT CHANCE POP INLAND FOR FIRST HALF OF THU IS REASONABLE BUT WILL BUMP UP POP TO CHC ALONG THE COAST FOR FIRST PART OF THU. A MUCH DRIER AND COOLER AIR MASS BUILDS IN BEHIND THE FRONT THU NIGHT INTO FRI. PRECIPITABLE WATER VALUES DROP UNDER 0.25 INCH BY FRI MORNING AND REMAIN BELOW 0.30 INCH THROUGH THE END OF THE PERIOD. ALTHOUGH THE DEEP DRY AIR WILL LEAD TO SUNNY SKIES COLD ADVECTION...WHICH WILL CONTINUE INTO FRI NIGHT...WILL KEEP TEMPERATURES BELOW TO WELL BELOW CLIMO. SOME AREAS WILL SEE HIGHS AROUND 60 FRI WITH LOWS IN THE MID 30S TO AROUND 40 FRI NIGHT. COMBINATION OF TIGHT GRADIENT AND MIXING OF STRONGER WINDS ALOFT COULD MAKE FRI A BREEZY DAY. BOUNDARY LAYER WINDS START TO WEAKEN FRI NIGHT BUT IT MAY BE A CASE OF TOO LITTLE TOO LATE AS FAR AS STRONG RADIATIONAL COOLING IS CONCERNED. && .LONG TERM /SATURDAY THROUGH TUESDAY/... AS OF 230 AM WEDNESDAY...FLAT MID LEVEL PATTERN WILL LEAD TO A RELATIVELY QUIET PERIOD WITH COLDEST AIR REMAINING TRAPPED WELL TO THE NORTH. HIGH PRESSURE IN CONTROL SAT WILL BE REINFORCED BY SECOND AREA OF HIGH PRESSURE FOLLOWING COLD FRONT EARLY SUN. FRONT PASSES DRY WITH NEXT TO NO COLD AIR...THE ONLY THING SIGNIFYING ITS PASSAGE WILL BE WINDS SHIFTING FROM SOUTHERLY TO NORTHWEST. DURING THE MIDDLE OF NEXT WEEK CLOUD COVER MAY START TO INCREASE AS MOISTURE ASSOCIATED WITH LOW PRESSURE DEVELOPING OVER THE MIDWEST SPREADS EAST. THIS SYSTEM IS UNLIKELY TO HAVE ANY SIGNIFICANT IMPACT ON THE CAROLINAS BEFORE THE END OF THE PERIOD. ZONAL FLOW ALOFT WILL HELP KEEP TEMPERATURES NEAR CLIMO THROUGH THE PERIOD...WITH THE EXCEPTION OF SAT WHEN TEMPERATURES MAY RUN A LITTLE BELOW CLIMO. && .AVIATION /18Z WEDNESDAY THROUGH MONDAY/... AS OF 18Z...LOOK FOR INCREASING ALTOCUMULUS CEILINGS THROUGH THE LATE AFTERNOON INTO THE EVENING HOURS. THE HRRR MODEL IS ADVERTISING SOME LIGHT SHOWERS ALONG THE COAST LATE THIS AFTERNOON...ASSOCIATED WITH A WEAK COASTAL TROUGH. BY LATE THIS EVENING...MODELS IN FAIRLY GOOD AGREEMENT INTRODUCING IFR CEILINGS/VISIBILITIES CAUSED BY INCREASING COVERAGE OF MAINLY LIGHT RAIN/SHOWER ACTIVITY. THE NAM MODEL MAY BE A BIT EARLY...BUT MODERATE CONFIDENCE WE WILL SEE IFR CONDITIONS AT ALL TERMINALS AFTER 06Z. MAINLY LIGHT WINDS OVERNIGHT...EXCEPT ALONG THE COAST WHERE ONSHORE WINDS COULD REMAIN IN THE 8-10 KNOT RANGE. THURSDAY...POSSIBILITY OF SHOWERS LATE AS A SURFACE LOW RIDES NORTHWARD AHEAD OF A COLD FRONT. LOW CONFIDENCE ON WIND DIRECTION THURSDAY...DUE TO THE LOW. EXTENDED OUTLOOK...CHANCE OF SHOWERS THURSDAY AFTERNOON WITH A COLD FRONT. VFR FRIDAY THROUGH SUNDAY. MORNING FOG POSSIBLE MONDAY. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 1230 PM WEDNESDAY...SMALL CRAFT ADVISORY ALLOWED TO EXPIRE ON SCHEDULE FOR THE SC WATERS AS THE WINDS/SEAS BEGIN TO SUBSIDE. NO SIGNIFICANT CHANGES. PREVIOUS DISCUSSION FROM 930 AM FOLLOWS... SMALL CRAFT ADVISORIES REMAIN POSTED FOR 6-7 FOOT SEAS MAINLY AT THE OUTER MARGIN OF THE SOUTH CAROLINA COASTAL WATERS AND BEYOND 5-10 MILES FROM SHORE ACROSS THE NC WATERS. THE CULPRIT IS A 1500+ MILE EASTERLY FETCH ACROSS MOST OF THE WESTERN ATLANTIC PRODUCED BY 1035 MB HIGH PRESSURE SOUTH OF NEWFOUNDLAND CANADA. AS THIS HIGH WEAKENS AND THE SYNOPTIC FLOW VEERS MORE SOUTHERLY WITH THE APPROACHING COLD FRONT THE FETCH SHOULD DIMINISH CONSIDERABLY DURING THE AFTERNOON. CHANGES WITH THIS MORNING UPDATE WERE GENERALLY MINOR...LIMITED TO COVERAGE OF SHOWERS BASED ON CURRENT RADAR IMAGERY AND RUC/HRRR PROGS THROUGH THE AFTERNOON. SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... AS OF 230 AM WEDNESDAY...SOUTHERLY FLOW AT THE START OF THE PERIOD WILL QUICKLY BECOME WESTERLY AS PRE-FRONTAL TROUGH CROSSES THE WATERS. STRENGTH OF OFFSHORE FLOW WILL BE LIMITED UNTIL AFTER PASSAGE OF COLD FRONT LATER THU. PINCHED PRESSURE GRADIENT AND COLD ADVECTION THU NIGHT AND FRI WILL LEAD TO OFFSHORE FLOW IN THE 20 TO 25 KT RANGE WITH GUSTS EXCEEDING 30 KT. GIVEN OFFSHORE TRAJECTORY AND LIMITED FETCH CONFIDENCE IN SEAS WITHIN 20 NM REACHING 6 FT FOR ALL ZONES IS LOW...THOUGH WIND SPEEDS ARE LIKELY TO BE ENOUGH TO WARRANT SCA THU NIGHT AND FRI MORNING. WIND SPEEDS DECREASE LATE FRI AND FRI NIGHT AND VEER TO NORTHEAST AS CENTER OF HIGH PRESSURE MOVES INTO THE CENTRAL APPALACHIANS AND THE GRADIENT WEAKENS. SEAS 2 TO 4 FT EARLY THU WILL BUILD TO 4 TO 7 FT THU NIGHT AND FRI. THE DECREASE IN SPEED AND VEERING OF WINDS LATER FRI AND FRI NIGHT WILL KNOCK SEAS BACK TO 3 TO 5 FT FOR THE LATER HALF OF THE PERIOD. LONG TERM /SATURDAY THROUGH SUNDAY/... AS OF 230 AM WEDNESDAY...HIGH PRESSURE WILL DOMINATE THE PERIOD...BROKEN BY PASSAGE OF RELATIVELY WEAK COLD FRONT SAT NIGHT INTO SUN. WINDS AND SEAS WILL BE DECREASING SAT AS HIGH PRESSURE SETTLES OVER THE WATERS AND THEN DRIFTS TO THE SOUTH SAT NIGHT. PASSAGE OF COLD FRONT LATE SAT NIGHT IS LIKELY TO BE MORE OF A WIND SHIFT THAN A TRUE FRONTAL PASSAGE. THERE WILL BE A SLIGHT INCREASE IN WINDS BEHIND THE FRONT AS GRADIENT BECOMES A LITTLE MORE DEFINED AND SLIGHTLY COOLER AIR BUILDS IN. SPEEDS WILL INCREASE FROM AROUND 10 KT ON SAT TO 10 TO 15 KT FOR SUN. SEAS WILL VARY FROM AROUND 2 FT TO 2 TO 3 FT. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EST THIS EVENING FOR AMZ250- 252. && $$ NEAR TERM...TRA SHORT TERM...III LONG TERM...III AVIATION...43/TRA
AREA FORECAST DISCUSSION...UPDATED
NWS GRAND FORKS ND
1247 PM CST WED NOV 6 2013 .UPDATE... ISSUED AT 1247 PM CST WED NOV 6 2013 MID-LEVEL CLOUD COVER HAS BECOME MORE CUMULIFORM AND IS MOVING MORE RAPIDLY TO THE EAST-SOUTHEAST THAN PREVIOUS RAP GUIDANCE. AS A RESULT...ADJUSTED SKY GRIDS TO MATCH LATEST TRENDS WITH CLEARING ACROSS MUCH OF THE FORECAST AREA BY EARLY EVENING. CLOUDS HAVE MADE A SMALL DENT IN TEMPERATURES...SO DECREASED AFTERNOON HIGHS A DEGREE OR TWO IN PLACES. REST OF THE FORECAST OK. UPDATE ISSUED AT 1007 AM CST WED NOV 6 2013 FORECAST AREA WILL REMAIN IN NORTHWEST FLOW ALOFT TODAY AS MAIN TROUGH AXIS SLIDES TO THE EAST. A WEAK SURFACE LOW WILL ALSO DRIFT ACROSS ND WITHIN A MORE DISORGANIZED AREA OF HIGH PRESSURE. NO PRECIPITATION EXPECTED WITH THIS PATTERN...BUT THERE IS AN AREA OF MID CLOUDS ACROSS MOST OF EASTERN ND AND INTO NORTHWEST MN THAT IS MOVING TO THE EAST AROUND 10 TO 15 MPH. RAP 850 TO 700 HPA RH HANDLES THIS WELL AND SUGGESTS CLOUD COVER WILL HOLD TOGETHER FOR MUCH OF THE DAY AS IT SLOWLY MOVES INTO WEST CENTRAL MN. FOR THIS...INCREASED SKY COVER A BIT MORE THROUGH MID-AFTERNOON. WILL HAVE TO WATCH HOW THIS IMPACTS TEMPERATURES...BUT FOR NOW MADE ONLY MINOR CHANGES BASED ON THE BEST PERFORMING BIAS CORRECTED NAM AND RAP GUIDANCE. REMAINDER OF THE FORECAST IN GOOD SHAPE WITH NO CHANGES NEEDED AT THIS TIME. UPDATE ISSUED AT 632 AM CST WED NOV 6 2013 WILL INCREASE CLOUD COVERAGE FOR TODAY AS AN AREA OF MID-LEVEL CIGS IS SLOWLY MOVING THROUGH THE REGION. THIS SHOULD NOT AFFECT THE MAX TEMP FORECAST. && .SHORT TERM...(TODAY THROUGH THURSDAY) ISSUED AT 330 AM CST WED NOV 6 2013 NORTHWEST FLOW ALOFT EXPECTED WITH FAST MOVING WEAK UPPER WAVES. THE AIRMASS WILL REMAIN VERY DRY WITH ONLY MID-UPPER CLOUDS RESULTING FROM THESE UPPER WAVES. TEMPERATURES SHOULD REMAIN SIMILAR TO PREVIOUS DAYS. CLOUDS WILL BE TRICKY TO FORECAST...AND WILL HAVE THE MOST IMPORTANCE ON THE TEMPERATURE FORECAST. DURING THE OVERNIGHT HOURS...EVEN THOUGH THERE MAY BE CLOUDS...ALSO THINK THAT THERE WILL BE PERIODS OF CLEAR SKIES. THIS WOULD ALLOW THE TEMPERATURE TO DROP TO NEAR THE COLDER GUIDANCE (MUCH LIKE WHAT IS CURRENTLY OCCURRING). .LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY) ISSUED AT 330 AM CST WED NOV 6 2013 THURSDAY NIGHT-FRIDAY NIGHT...UPPER FLOW WILL BECOME MORE ZONAL AHEAD OF A STRONGER WAVE EJECTING FROM THE PAC NW. CONFIDENCE IS STILL LOW WITH REGARDS TO DETAILS ON FRIDAY WITH THE PASSAGE OF THE THIS WAVE. THE MAIN SIGNAL THAT THE MODELS ARE GIVING IS THAT THERE MAY BE TWO UPPER WAVES...ONE ACROSS SOUTHERN CANADA...AND ANOTHER ACROSS THE NORTHERN CONUS. THE INTERACTIONS BETWEEN THESE TWO WAVES ARE LIKELY CAUSING THE MODEL DIFFERENCES. WILL KEEP THE HIGHER END CHANCE POPS WITH RAIN OR SNOW POSSIBLE. SATURDAY-TUESDAY...THERE REMAINS FAIR AGREEMENT WITH THE MODELS IN THE TIME FRAME TO BRING DOWN A WEAK WAVE WITH CHC POPS UNDER NW 500MB FLOW ALOFT ON SUNDAY NIGHT. A COLD 1040MB SFC HIGH PRESSURE ON MON/TUES WILL ESCORT DOWN BELOW NORMAL TEMPS TO THE NORTHERN PLAINS. HOW COLD DEPENDS ON TRACK OF THE CENTER OF THE HIGH WHERE GFS IS FARTHER NORTHEAST KEEPING THE STRONGEST PORTION OF THE COLD POOL IN MANITOBA/QUEBEC AND DROPPING SOUTH OVER THE GREAT LAKES. ECMWF IS A BIT FARTHER SOUTH AND REMAINS COOL BUT NOT AS COLD FOR THE EARLY PART OF NEXT WEEK. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON) ISSUED AT 1247 PM CST WED NOV 6 2013 MID LEVEL CLOUD DECK TO CONTINUE TO SHIFT SE AND THIN REMAINDER OF THIS AFTERNOON AND EVENING. MVFR SC DECK OVER NE CORNER OF THE FORECAST AREA NOT MAKING MUCH PROGRESS SOUTHWARD AND HAVE LEFT OUT OF THE BJI TAF BUT MAY NEED TO BE MONITORED. REMAINDER OF THE AREA VFR THROUGH THE FORECAST PERIOD. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ UPDATE...ROGERS SHORT TERM...TG LONG TERM...TG/JK AVIATION...VOELKER
AREA FORECAST DISCUSSION...UPDATED
NWS GRAND FORKS ND
1007 AM CST WED NOV 6 2013 .UPDATE... ISSUED AT 1007 AM CST WED NOV 6 2013 FORECAST AREA WILL REMAIN IN NORTHWEST FLOW ALOFT TODAY AS MAIN TROUGH AXIS SLIDES TO THE EAST. A WEAK SURFACE LOW WILL ALSO DRIFT ACROSS ND WITHIN A MORE DISORGANIZED AREA OF HIGH PRESSURE. NO PRECIPITATION EXPECTED WITH THIS PATTERN...BUT THERE IS AN AREA OF MID CLOUDS ACROSS MOST OF EASTERN ND AND INTO NORTHWEST MN THAT IS MOVING TO THE EAST AROUND 10 TO 15 MPH. RAP 850 TO 700 HPA RH HANDLES THIS WELL AND SUGGESTS CLOUD COVER WILL HOLD TOGETHER FOR MUCH OF THE DAY AS IT SLOWLY MOVES INTO WEST CENTRAL MN. FOR THIS...INCREASED SKY COVER A BIT MORE THROUGH MID-AFTERNOON. WILL HAVE TO WATCH HOW THIS IMPACTS TEMPERATURES...BUT FOR NOW MADE ONLY MINOR CHANGES BASED ON THE BEST PERFORMING BIAS CORRECTED NAM AND RAP GUIDANCE. REMAINDER OF THE FORECAST IN GOOD SHAPE WITH NO CHANGES NEEDED AT THIS TIME. UPDATE ISSUED AT 632 AM CST WED NOV 6 2013 WILL INCREASE CLOUD COVERAGE FOR TODAY AS AN AREA OF MID-LEVEL CIGS IS SLOWLY MOVING THROUGH THE REGION. THIS SHOULD NOT AFFECT THE MAX TEMP FORECAST. && .SHORT TERM...(TODAY THROUGH THURSDAY) ISSUED AT 330 AM CST WED NOV 6 2013 NORTHWEST FLOW ALOFT EXPECTED WITH FAST MOVING WEAK UPPER WAVES. THE AIRMASS WILL REMAIN VERY DRY WITH ONLY MID-UPPER CLOUDS RESULTING FROM THESE UPPER WAVES. TEMPERATURES SHOULD REMAIN SIMILAR TO PREVIOUS DAYS. CLOUDS WILL BE TRICKY TO FORECAST...AND WILL HAVE THE MOST IMPORTANCE ON THE TEMPERATURE FORECAST. DURING THE OVERNIGHT HOURS...EVEN THOUGH THERE MAY BE CLOUDS...ALSO THINK THAT THERE WILL BE PERIODS OF CLEAR SKIES. THIS WOULD ALLOW THE TEMPERATURE TO DROP TO NEAR THE COLDER GUIDANCE (MUCH LIKE WHAT IS CURRENTLY OCCURRING). .LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY) ISSUED AT 330 AM CST WED NOV 6 2013 THURSDAY NIGHT-FRIDAY NIGHT...UPPER FLOW WILL BECOME MORE ZONAL AHEAD OF A STRONGER WAVE EJECTING FROM THE PAC NW. CONFIDENCE IS STILL LOW WITH REGARDS TO DETAILS ON FRIDAY WITH THE PASSAGE OF THE THIS WAVE. THE MAIN SIGNAL THAT THE MODELS ARE GIVING IS THAT THERE MAY BE TWO UPPER WAVES...ONE ACROSS SOUTHERN CANADA...AND ANOTHER ACROSS THE NORTHERN CONUS. THE INTERACTIONS BETWEEN THESE TWO WAVES ARE LIKELY CAUSING THE MODEL DIFFERENCES. WILL KEEP THE HIGHER END CHANCE POPS WITH RAIN OR SNOW POSSIBLE. SATURDAY-TUESDAY...THERE REMAINS FAIR AGREEMENT WITH THE MODELS IN THE TIME FRAME TO BRING DOWN A WEAK WAVE WITH CHC POPS UNDER NW 500MB FLOW ALOFT ON SUNDAY NIGHT. A COLD 1040MB SFC HIGH PRESSURE ON MON/TUES WILL ESCORT DOWN BELOW NORMAL TEMPS TO THE NORTHERN PLAINS. HOW COLD DEPENDS ON TRACK OF THE CENTER OF THE HIGH WHERE GFS IS FARTHER NORTHEAST KEEPING THE STRONGEST PORTION OF THE COLD POOL IN MANITOBA/QUEBEC AND DROPPING SOUTH OVER THE GREAT LAKES. ECMWF IS A BIT FARTHER SOUTH AND REMAINS COOL BUT NOT AS COLD FOR THE EARLY PART OF NEXT WEEK. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING) ISSUED AT 632 AM CST WED NOV 6 2013 MID-LEVEL CIGS WILL AFFECT THE REGION TODAY. WILL NEED TO KEEP AN EYE ON KBJI AS THERE ARE MVFR CIGS MOVING TOWARD THIS AREA FROM THE NORTH. CURRENT THINKING IS THAT THESE CIGS WILL JUST MISS THIS SITE...BUT IT WILL BE CLOSE. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ UPDATE...ROGERS SHORT TERM...TG LONG TERM...TG/JK AVIATION...TG