Forecast Discussions mentioning any of "HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 03/31/14


AREA FORECAST DISCUSSION
NWS RENO NV
308 PM PDT SAT MAR 29 2014 .SYNOPSIS... RAIN AND SNOW WILL CONTINUE THROUGH TONIGHT AS A LATE SEASON WINTER STORM MOVES ACROSS THE SIERRA. A COLDER STORM SYSTEM WILL IMPACT THE REGION MONDAY AND TUESDAY WITH LIGHT SNOW POSSIBLE IN LOWER ELEVATIONS. BELOW NORMAL TEMPERATURES ARE EXPECTED THROUGH MUCH OF THE UPCOMING WEEK, WITH ANOTHER CHANCE OF RAIN AND SNOW SHOWERS THURSDAY AND FRIDAY. && .SHORT TERM... PRECIPITATION CONTINUES TO INTENSIFY NEAR AND WEST OF THE SIERRA CREST AS MAIN TROUGH APPROACHES THE CALIFORNIA COAST. UPPER LEVEL JET WILL ALSO MOVE ONSHORE AND ENHANCE THE MOISTURE BAND. SNOW LEVELS EAST OF THE SIERRA CREST NEAR TAHOE HAVE REMAINED NEAR 6500-7000 FEET BUT SHOULD DROP TO LAKE LEVEL BEFORE 5 PM. SNOWFALL RATES OF 1-2 INCHES PER HOUR ARE LIKELY TO PERSIST A PERIOD OF 6-8 HOURS, AND TRAVEL IMPACTS WILL INCREASE THIS EVENING AS SNOW BEGINS ACCUMULATING ON PAVED SURFACES. THEREFORE THE WARNING WILL REMAIN IN PLACE. FARTHER NORTH INTO LASSEN COUNTY, ALTHOUGH SOME SNOW HAS ALREADY ACCUMULATED ABOVE 5500 FEET, THE HEAVIER SNOW IS ALSO EXPECTED TO END SOONER, SO THE ADVISORY SHOULD BE SUFFICIENT. LOCALIZED SNOW SHOWER BANDS MAY CONTINUE LATER TONIGHT, DEPENDING ON HOW MUCH CONVECTIVE ACTIVITY DEVELOPS IN NORTH CENTRAL CA DURING THE NEXT FEW HOURS. FOR MONO COUNTY, SNOW WILL INCREASE THIS EVENING, SPREADING SOUTHWARD ALONG THE SIERRA AND PROBABLY REACHING THE MAMMOTH LAKES VICINITY BY 8 PM. BEFORE THE SNOW ARRIVES, WINDY CONDITIONS WILL CONTINUE, SO THE ADVISORY WILL BE EXTENDED FOR A FEW MORE HOURS. SINCE ALL OF THE SNOW WILL FALL IN A COMPRESSED TIME PERIOD AND THE BAND WILL BEGIN TO WEAKEN LATE TONIGHT, SNOW TOTALS NEAR THE CREST MAY TOP OUT CLOSER TO 16 INCHES INSTEAD OF THE ORIGINAL 20 INCH PROJECTION. HOWEVER, IMPACTS WILL STILL BE SUFFICIENT TO KEEP THE WARNING IN PLACE TONIGHT. FOR WESTERN NV, THE RAIN SHADOW HAS PERSISTED SO FAR THIS AFTERNOON. HOWEVER, THE LAST FEW RUNS OF THE HRRR MODEL HAVE INDICATED RAPID SPILLOVER INTO THE RENO-CARSON VICINITY BETWEEN 4 AND 5 PM, WITH UP TO 6 HOURS OF NEARLY STEADY RAIN THROUGH THIS EVENING. IF THIS OCCURS, RAINFALL COULD STILL ADD UP TO BETWEEN 0.25 AND 0.50 INCH, WITH LOCALLY HIGHER AMOUNTS IN FOOTHILL LOCATIONS. FOR AREAS SOUTH OF HIGHWAY 50, THE MAJORITY OF THE RAIN WILL FALL DURING THE LATE EVENING AND OVERNIGHT HOURS. THE PRECIP COULD END AS SNOW BELOW 5000 FEET, BUT LITTLE OR NO SNOW ACCUMULATION IS EXPECTED IN VALLEYS. ABOVE 5000 FEET, A COUPLE INCHES MAY ACCUMULATE, BUT SOME LOCALLY HIGHER AMOUNTS MAY FALL IN DOUGLAS COUNTY AS THE COLD AIR ARRIVES IN CONJUNCTION WITH THE ONGOING HEAVIER PRECIP BAND. THIS OCCURRED WITH ONE OF THE STORMS EARLIER THIS SEASON SO THIS WOULD NEED TO BE MONITORED LATER TONIGHT. ALL GUIDANCE IS IN AGREEMENT FOR A RAPID DISSIPATION OF THE RAIN AND SNOW BY EARLY SUNDAY MORNING. FOR SUNDAY, A FEW SHOWERS MAY LINGER NEAR THE SIERRA AND IN WEST CENTRAL NV EAST OF HIGHWAY 95, OTHERWISE MOSTLY CLOUDY AND DRY CONDITIONS WILL PREVAIL WITH MODERATE WEST WINDS GUSTING TO 20-30 MPH IN THE AFTERNOON. MJD A COLDER LOW PRESSURE WILL DROP ALONG THE WEST COAST EARLY NEXT WEEK, BRINGING ADDITIONAL PRECIPITATION TO THE SIERRA AND WESTERN NEVADA. THIS LOW WILL BRING VERY COLD AIR DOWN FROM THE GULF OF ALASKA WITH 700MB NEAR -10C. SNOW LEVELS WILL FALL TO MOST VALLEY FLOORS BY MONDAY NIGHT AND INTO TUESDAY MORNING. THAT BEING SAID, THE LATEST MODEL RUNS OF THE GFS AND ECMWF HAVE BACKED OFF ON PRECIPITATION AMOUNTS IN WESTERN NEVADA, LEADING TO CONTINUED UNCERTAINTY AND LOW FORECASTER CONFIDENCE. THIS IS MAINLY BECAUSE THE LOW IS TRYING TO SPLIT OFF TO THE SOUTH AND DRIVE THE JET AND DYNAMICS WELL INTO SOUTHERN CA. THE HIGHEST CHANCES FOR SNOW WILL REMAIN IN THE SIERRA LATE MONDAY AS THE FIRST SHORTWAVE MOVES THROUGH NORTHERN CA. THE 500MB SHORTWAVE LOOKS TO BECOME NEGATIVELY TILTED, WHICH IS IS NOT NECESSARILY GOOD FOR SPILLOVER. BUT, WE SHOULD BE UNSTABLE ENOUGH FOR SOME LIGHT SPILLOVER IF THE JET REMAINS SOUTH OF MONO COUNTY. BY TUESDAY, LOW PRESSURE REMAINS OVER THE REGION WITH CONVECTIVE SHOWERS DEVELOPING UNDER THE COLD POOL. INSTABILITY LOOKS FAIRLY STRONG DUE TO THE INCREASED SOLAR HEATING. WE WILL NEED TO KEEP A CLOSE EYE, BECAUSE A SURFACE LOW DEVELOPING OVER SOUTHERN NEVADA MAY CREATE SOME LOW-LEVEL FORCING THAT COULD INCREASE PRECIPITATION RATES IN THE EASTERN SIERRA AND WESTERN NEVADA. HOON .LONG TERM...WEDNESDAY THROUGH SATURDAY... FORECAST REMAINS UNCERTAIN FOR THE SYSTEM AT THE END OF NEXT WEEK. DETERMINISTIC SOLUTIONS HAVE LARGELY DIVERGED WITH THE GFS PRESENTING A SPLIT SYSTEM WILL VERY LITTLE PRECIPITATION; THE EC SHOWS A MORE CONSOLIDATED FRONT WITH LOW PRESSURE IN CENTRAL OREGON AND DECENT PRECIP ALONG THE SIERRA. THEREFORE, VERY FEW ADJUSTMENTS TO THE EXISTING FORECAST FAVORING A BLENDED APPROACH WITH 30-40% CHANCE OF PRECIP ALONG THE SIERRA FROM THURSDAY INTO SATURDAY. TEMPERATURES CONTINUE TO LOOK AROUND TO SLIGHTLY COOLER THAN SEASONAL AVERAGES WITH MODEST COLD AIR ALOFT AT 700MB AND AMPLE CLOUD COVER. HOPEFULLY SOLUTIONS WILL BEGIN TO CONVERGE OVER THE NEXT DAY OR SO TO ALLOW FOR HIGHER DETAILS. BOYD && .AVIATION... A CHANGEOVER TO SNOW IS EXPECTED BY 00Z AROUND THE TAHOE BASIN, WITH ABOUT 6-8 HOURS OF CIGS/VSBY BELOW LANDING MINIMUMS AT KTVL/KTRK THIS EVENING AND INTO THE LATE NIGHT. FOR KMMH, THE WORST CONDITIONS ARE LIKELY FROM 03Z-12Z FROM THIS SAME SNOW BAND. CONDITIONS WILL IMPROVE SUNDAY MORNING ALTHOUGH SOME MVFR CIGS COULD LINGER THROUGH MUCH OF THE DAY AS RESIDUAL MOISTURE REMAINS IN PLACE. FOR WESTERN NV INCLUDING KRNO-KCXP, RAIN WILL INCREASE AROUND 00Z, PRODUCING MVFR CIGS/VSBY AT TIMES FOR 4-6 HOURS THIS EVENING. THIS PRECIP MAY BRIEFLY END AS SNOW, BUT LITTLE OR NO SNOW ACCUMULATION IS EXPECTED ON RUNWAYS. VFR CONDITIONS ARE EXPECTED SUNDAY ALTHOUGH SOME MOUNTAIN OBSCURATIONS WILL REMAIN POSSIBLE DUE TO RESIDUAL CLOUD COVER. MJD && .REV WATCHES/WARNINGS/ADVISORIES... NV...WINTER STORM WARNING UNTIL 5 AM PDT SUNDAY NVZ002. LAKE WIND ADVISORY UNTIL 8 PM PDT THIS EVENING FOR PYRAMID LAKE IN NVZ004. CA...WINTER WEATHER ADVISORY UNTIL 5 AM PDT SUNDAY ABOVE 5500 FEET FOR CAZ071. WIND ADVISORY UNTIL 8 PM PDT THIS EVENING CAZ073. WINTER STORM WARNING FROM 8 PM THIS EVENING TO 5 AM PDT SUNDAY CAZ073. WINTER STORM WARNING UNTIL 5 AM PDT SUNDAY CAZ072. && $$ FOR MORE INFORMATION FROM THE NATIONAL WEATHER SERVICE VISIT... HTTP://WEATHER.GOV/RENO (ALL LOWER CASE)
AREA FORECAST DISCUSSION...UPDATED
NWS RENO NV
1112 AM PDT SAT MAR 29 2014 .UPDATE... WE EXTENDED THE WIND ADVISORY FOR THE RENO ZONE THRU 3 PM. GUSTS TO 50 MPH WERE RECENTLY REPORTED AT THE RENO AIRPORT AND PORTIONS OF WASHOE VALLEY. SOME BLOWING DUST WAS STILL OBSERVED OUTSIDE THE WINDOW NEAR THE EAST END OF THE CITY. LATEST HRRR GUIDANCE SHOWS A FEW MORE HOURS OF SHADOWING BEFORE RAIN SPILLS OVER INTO RENO- CARSON CITY, SO LOCALLY STRONG GUSTS SHOULD CONTINUE UNTIL THEN. REMAINDER OF FORECAST STILL ON TRACK WITH NO OTHER CHANGES TO HEADLINES. SNOW LEVELS AROUND 6500 FEET WEST OF TAHOE SHOULD DROP TO LAKE LEVEL BY MID AFTERNOON. MJD && .PREVIOUS DISCUSSION... /ISSUED 327 AM PDT SAT MAR 29 2014/ SYNOPSIS... A LATE SEASON WINTER STORM WILL BRING HEAVY SNOW IN THE SIERRA AND RAIN FOR LOWER ELEVATIONS THROUGH TONIGHT. A COLDER STORM SYSTEM WILL IMPACT THE REGION NEXT MONDAY AND TUESDAY WITH LIGHT SNOW POSSIBLE IN LOWER ELEVATIONS. BELOW NORMAL TEMPERATURES ARE EXPECTED THROUGH MUCH OF THE UPCOMING WEEK, WITH LIGHT RAIN AND SNOW SHOWERS POSSIBLE AGAIN LATE NEXT WEEK. SHORT TERM... PRECIPITATION CONTINUES ITS SLOW PROGRESSION ACROSS NORTHERN CALIFORNIA MAINLY NORTH OF I-80. AREA WEBCAMS SHOWING SNOW BEGINNING TO MIX WITH RAIN AT BOGARD IN WESTERN LASSEN COUNTY WITH SURFACE TEMPERATURES A FEW DEGREES ABOVE FREEZING. THIS PRECIP WILL CONTINUE TO WORK ITS WAY SOUTH ACROSS THE SIERRA TODAY WITH PERIODS OF HEAVY SNOWFALL EXPECTED THIS AFTERNOON ACROSS THE SIERRA IN THE TAHOE BASIN AND THIS EVENING IN MONO COUNTY. GUSTY WINDS HAVE DEVELOPED AHEAD OF THE PRECIPITATION WITH SOME OF THE WIND PRONE AREAS ALREADY GUSTING INTO THE 60-70 MPH RANGE. OUTSIDE OF THE WIND PRONE REGIONS WIND GUSTS HAVE BEEN GENERALLY IN THE 20-30 MPH RANGE. 700MB FLOW WILL PEAK THIS MORNING WITH THE SURFACE GRADIENT INCREASING AS THE SURFACE LOW DEEPENS. AS SUCH, WILL ISSUE A WIND ADVISORY COVERING AREAS IN THE LEE OF THE SIERRA WHICH WILL INCLUDE THE RENO/CARSON/GARDNERVILLE REGION ALONG WITH MONO COUNTY. WIND GUSTS OF 50 MPH ARE POSSIBLE ACROSS VALLEY AREAS WITH WIND PRONE AREAS CONTINUING IN THE 60-70 MPH RANGE. HAZARDOUS BOATING CONDITIONS ARE ALSO EXPECTED ACROSS AREAS LAKES. WINDS WILL DIMINISH THIS AFTERNOON WITH THE ARRIVAL OF THE PRECIPITATION AND FRONT. HEAVY SNOWFALL WILL IMPACT AREAS ABOVE 7000 FEET THIS MORNING BEFORE SNOW LEVELS STEADILY DROP THROUGH THE DAY AS COLDER AIR ALOFT FILTERS INTO THE REGION. THIS SYSTEM WILL FEATURE DYNAMIC SUPPORT VIA A COUPLED JET AND FRONTOGENETICAL FORCING WHICH WILL PROVIDE PERIODS OF HEAVY SNOWFALL ABOVE 7000 FEET ALLOWING FOR SNOWFALL RATES HEAVY ENOUGH TO ACCUMULATE ON ROADWAYS RESULTING IN TRAVEL IMPACTS ACROSS PASSES. SNOW LEVELS LOOK TO FALL TO LAKE LEVEL DURING THE AFTERNOON SOMEWHERE BETWEEN 3-6PM. PERIODS OF CHANGEOVER TO SNOW ARE POSSIBLE EARLIER WITHIN HEAVIER BANDS OF PRECIP. ALL TOLD SNOWFALL TOTALS THROUGH SUNDAY MORNING COULD SEE UPWARDS OF 2 FEET ACROSS THE CREST WITH GENERALLY ABOUT 6-12" POSSIBLE BELOW 7000 FEET, HIGHEST ALONG THE WESTERN SIDE OF THE BASIN. SPILLOVER IS LIKELY INTO WESTERN NEVADA LATE SATURDAY AFTERNOON INTO EARLY EVENING WITH THE PRESENCE OF DYNAMIC FORCING. A QUARTER TO A THIRD OF AN INCH OF RAINFALL IS POSSIBLE WITH THE FRONT WITH SNOWFALL POSSIBLE IN THE FOOTHILLS AS SNOW LEVELS QUICKLY FALL TO NEAR 5000 FEET WITH THE FRONT. TIMING ACROSS MONO COUNTY FOR THE HEAVIEST PRECIPITATION STILL LOOKS TO BE THIS EVENING AND TONIGHT AS THE COUPLED JET SYSTEM TRACKS SOUTH. SNOWFALL ACCUMULATIONS OF 1.5-2 FEET STILL POSSIBLE ACROSS THE CREST IN MONO COUNTY WITH HIGHER AMOUNTS ACROSS THE NORTHERN HALF OF THE COUNTY. SHOWERS TAPER OFF SUNDAY MORNING WITH A BREAK BETWEEN SYSTEMS THROUGH EARLY MONDAY AS A COLDER SYSTEM IS POISED TO PROVIDE ANOTHER ROUND OF SNOWFALL TO THE SIERRA WITH SNOW LEVELS LOW ENOUGH TO EVEN PROVIDE SNOW TO THE VALLEY AREAS ACROSS WESTERN NEVADA BY MONDAY NIGHT. THOUGH THE BEST JET DYNAMICS LOOK TO REMAIN SOUTH OF THE REGION, THE COLDER AIRMASS SHOULD PROVIDE FOR HIGHER RATIO SNOWFALLS WITH AN ADDITIONAL FOOT OF SNOWFALL POSSIBLE ACROSS THE SIERRA AND LIGHT ACCUMULATIONS POSSIBLE DOWN AT THE VALLEY FLOORS IN WESTERN NEVADA. FUENTES LONG TERM...TUESDAY THROUGH FRIDAY... MADE FEW CHANGES TO THE LONG TERM FORECAST, BUT UNCERTAINTY IS A BIT HIGHER THIS MORNING THAN 24 HOURS AGO. MODELS ARE STRUGGLING A BIT MORE WITH THE SPLITTING OF THE UPPER LOW TUESDAY AS IT COMES IN AS WELL AS THE NEXT SYSTEM FOR LATE IN THE WEEK. THE UPPER LOW IS NOW FORECAST BY THE MODELS TO DROP WEST OF THE AREA WITH MORE OF A SPLIT ON TUESDAY. DESPITE THIS OCCURRING, THERE WILL STILL BE PLENTY OF COLD AIR ALOFT FOR SOME SHOWERS TUESDAY ALL ACROSS THE SIERRA AND WESTERN NEVADA. THERE COULD ALSO BE A THUNDERSTORM OR TWO, BUT WILL LEAVE THAT OUT FOR NOW AS IT STILL LOOKS MARGINAL. SLOW DRYING TUESDAY NIGHT AS THE LOW PULLS AWAY. WEDNESDAY LOOKS MOSTLY DRY RIGHT NOW, BUT THE EC AND A COUPLE GFS ENSEMBLE MEMBERS SHOW ENOUGH COLD AIR AND MOISTURE ALOFT REMAIN FOR A COUPLE SHOWERS. WILL HAVE TO KEEP AN EYE ON THAT. FOR THE NEXT SYSTEM LATE IN THE WEEK, THE MODELS SHOW WIDELY VARYING SOLUTIONS. THE EC BRINGS IN ANOTHER UPPER LOW SLOWLY WHILE THE GFS KEEPS AN OPEN WAVE WITH THE JET STREAM REMAINING NORTH INTO OREGON. HAVE NOT CHANGED ANYTHING YET AS IT STILL LOOKS TO BE SOMEWHAT WET AND SLIGHT CHC TO CHC POPS LOOK GOOD FOR NOW. WITH THE UPPER LOW AND SYSTEMS MOVING THROUGH, EXPECT TEMPS TO REMAIN A BIT BELOW AVERAGE FOR THE WEEK WITH TUESDAY BEING THE COLDEST DAY. OVERNIGHT LOWS WILL BE CLOSER TO NORMAL DUE TO THE MOISTURE AND CLOUD COVER. WALLMANN AVIATION... BAND OF MODERATE/HEAVY RAIN AND SNOW IS NOW MOVING INTO THE SIERRA NORTH OF LAKE TAHOE. THIS BAND WILL SLOWLY SHIFT SOUTH DURING THE DAY AND PUSH THROUGH MONO COUNTY BY THIS TIME TOMORROW. FOR THE SIERRA TERMINALS: EXPECT MOSTLY RAIN THROUGH MID-AFTERNOON WITH SNOW LEVELS NEAR 7000 FEET AT KTRK/KTVL. CIGS/VIS TO REMAIN MVFR TO OCNL IFR THRU 22Z AND THERE COULD BE SOME ICING ISSUES ALOFT. TRANSITION TO SNOW BETWEEN 22-00Z WITH 70% CONFIDENCE WITH HEAVY SNOW THEREAFTER THROUGH 06Z BLO KTRK/KTVL MINIMUMS. RUNWAY ACCUM AROUND 6 INCHES. IMPROVING CONDS THEREAFTER. FOR KMMH, SOME GUSTY WINDS TO 40 KTS THROUGH 22Z WITH SIGNIFICANT TURBULENCE BEFORE -RA BEGINS AFTER 00Z. CHANGES TO SNOW 03-06Z WITH IFR CONDS AND 2-4 INCHES RUNWAY ACCUMULATION WITH CONFIDENCE 60-70%. KRNO/KCXP: GUSTY WINDS TO 35 KTS THIS MORNING WITH MTN WAVE TURBULENCE AND LIMITED LLWS THROUGH 18Z. AS BAND SHIFTS SOUTH, MORE FAVORABLE FOR SPILLOVER SO EXPECT WINDS TO DIMINISH TO LESS THAN 20 KTS. WITH MVFR CIGS/VIS IN RA 20-03Z AND 70% CONFIDENCE. -RA WILL CHANGE TO -SN AS IT ENDS AROUND 03Z, BUT NO RUNWAY ACCUMULATION. EXPECT VFR CONDS THEREAFTER WITH AN OCCASIONAL STRAY -SHSN OVERNIGHT. WALLMANN && .REV WATCHES/WARNINGS/ADVISORIES... NV...WINTER STORM WARNING UNTIL 5 AM PDT SUNDAY NVZ002. WIND ADVISORY UNTIL 3 PM PDT THIS AFTERNOON NVZ003. LAKE WIND ADVISORY UNTIL 5 PM PDT THIS AFTERNOON FOR PYRAMID LAKE IN NVZ004. CA...WINTER WEATHER ADVISORY UNTIL 5 AM PDT SUNDAY ABOVE 5500 FEET FOR CAZ071. WIND ADVISORY UNTIL 5 PM PDT THIS AFTERNOON CAZ073. WINTER STORM WARNING FROM 5 PM THIS AFTERNOON TO 5 AM PDT SUNDAY CAZ073. WINTER STORM WARNING UNTIL 5 AM PDT SUNDAY CAZ072. && $$ FOR MORE INFORMATION FROM THE NATIONAL WEATHER SERVICE VISIT... HTTP://WEATHER.GOV/RENO (ALL LOWER CASE)
AREA FORECAST DISCUSSION
NWS SACRAMENTO CA
346 AM PDT Sat Mar 29 2014 .Synopsis... Rain and mountain snow over Interior Northern California today with a threat of afternoon thunderstorms...decreasing Sunday. A colder and wetter storm impacts the area Monday and Tuesday with another system possible towards the end of the week. && .Discussion... Pacific front will work its way through Interior NorCal this morning with steady precip turning showery behind the baroclinic zone. Periods of moderate to heavy snow and gusty wind expected in the Western Plumas and Northern Sierra Nevada today as the storm tracks through. Snow levels this morning running around 6000 to 6500 feet but will lower to around 5000 to 5500 feet later today behind the front. Both the HRRR and local WRF showing an area of 500+ J/kg CAPE developing over the Northern Sac Valley later this morning with increasing instability spreading southward in the Central Valley and east towards the foothills this afternoon. Shear profiles do support potential for rotating updrafts although they are not as favorable as with the system that moved through Wednesday. Highs today expected only in the lower 60s for the Central Valley with generally 40s to 50s for the mountains and foothills. Upper trough and associated cold pool aloft moves through tonight for continued shower threat then weak ridging Sunday. This will be short lived as the next colder deeper system approaches NorCal. Some model differences exist with timing but in general precip looks to begin over the Coastal and Western Shasta mountains Monday morning...spreading south and east over the entire CWA by the afternoon. Snow levels could drop to near the upper foothills with this system as it moves through Mon/Tue. Also, potential for more thunderstorms, with small hail, looks to be a good bet on Tue. Well below normal temps early next week with highs only in the 50s for the Central Valley with 30s to 40s in the mountains/foothills on Tuesday. .Extended Discussion (Wednesday through Saturday) Short-wave ridging forecast to move over NorCal Wednesday behind departing cold upper low moving into the desert SW. This will result in decreasing POPS for the region mid-week along with milder temperatures. Forecast uncertainty increases the second half of next week as models show little consistency in handling of the next trough forecast to potentially affect the region later Thu-Sat, so will continue to mention chance category POPS for now. && .Aviation... Pacific frontal sys moves swd thru NorCal today. For the valley... VFR conds expected next 24 hrs exc areas of MVFR cigs and sly sfc wind gusts 20-30 kts ahead of frontal passage thru abt 20Z. Sct -shra with isold TSRA behind front for this aftn and evening. Over nrn Siernev...wdsprd IFR conds RA/SN cont thru 12Z Sun. Sn lvls 055-065 this morning...lowering to 040-045 aft 00Z Sun. && .STO Watches/Warnings/Advisories... Winter Storm Warning until 5 am pdt Sunday above 5500 feet in the West Slope Northern Sierra Nevada...Western Plumas county/Lassen Park. && $$
AREA FORECAST DISCUSSION
NWS NEW YORK NY
1014 PM EDT SUN MAR 30 2014 .SYNOPSIS... LOW PRESSURE SOUTH OF LONG ISLAND TONIGHT MOVES EAST THROUGH MONDAY. HIGH PRESSURE BUILDS ACROSS THE AREA ON TUE. A WEAK COLD FRONT MOVES INTO THE AREA TUESDAY NIGHT FOLLOWED BY HIGH PRESSURE NOSING IN FROM THE NORTH ON THURSDAY. A FRONTAL SYSTEM IS EXPECTED TO IMPACT THE AREA AT THE END OF THE WEEK. && .NEAR TERM /UNTIL 6 AM MONDAY MORNING/... FLOOD WATCH IS CANCELLED. VERTICALLY STACKED LOW PRES JUST OFF THE NJ COAST APPEARS TO STARTING NOW STARTING ITS EASTWARD DRIFT AS SEEN IN WATER VAPOR IMAGERY LOOP. DEFORMATION PCPN BAND OVER EASTERN PA SHOULD START MOVING SOON AS WELL...THOUGH ITS BEEN STATIONARY ALL SHIFT. UNTIL THE DEFORMATION BAND GETS HERE...IT`S MOSTLY -DZ. LATEST 23Z HRRR SIMULATED REFLECTIVITY IS VERY STRANGE IN HOW IT DISSIPATES THE BAND AND THEN REFORMS IT OVER FAR WESTERN CT/LI AFTER MIDNIGHT. 00Z RAP HAS THIS SAME IDEA AS DOES THE 00Z NAM. THIS IS TROUBLESOME AS THIS SUGGESTS ENOUGH OMEGA FOR COLUMN COOLING AND A WINTRY MIX. FORTUNATELY...SFC TEMPS ARE WARM ENOUGH THAT THERE CAN NOT FORESEE ANY TRAVEL ISSUES IN THE MORNING. WILL CONTINUE TO MONITOR EVOLUTION. GUSTY NLY WINDS CONTINUE OVERNIGHT WITH TIGHT PRES GRADIENT BETWEEN HIGH PRES BUILDING IN FROM THE NORTH AND LOW PRES SOUTH OF LONG ISLAND. TEMPS MAY APPROACH THE FREEZING MARK BY MONDAY MORNING IN AREAS WELL INLAND...OTHERWISE...LOWS WILL DROP INTO THE MID 30S. && .SHORT TERM /6 AM MONDAY MORNING THROUGH MONDAY NIGHT/... RAIN ENDS FROM WEST TO EAST MONDAY MORNING...BUT MAY LINGER ACROSS FAR PORTIONS OF SE CT UNTIL MID AFTN. SKIES CLEAR OUT DURING THE DAY AS HIGH PRES BUILDS EAST. TIGHT GRADIENT WILL RESULT IN N WINDS 15-25 MPH WITH GUSTS UP TO 40 MPH. MORNING WIND CHILLS WILL BE IN THE 20S. CLEAR AND COLD MONDAY NIGHT. WITH CLEAR SKIES AND DIMINISHING WINDS...LOWS WILL DROP WELL INTO THE 20S ACROSS OUTLYING AREAS...AND WILL OTHERWISE BE IN THE LOW TO MID 30S. && .LONG TERM /TUESDAY THROUGH SUNDAY/... MODELS ARE IN GOOD AGREEMENT WITH THE H5 PATTERN THROUGH THE MIDDLE OF THE WEEK...AND HAVE SOMEWHAT BETTER AGREEMENT WITH THE TROUGH EJECTING OUT OF THE ROCKIES AND TRACKING THROUGH THE GREAT LAKES AT THE END OF THE WEEK. THERE ARE STILL ISSUES WITH TIMING AND STRENGTH. SO WHILE THE DETAILS REMAIN IN QUESTION...THERE IS A GOOD CHANCE WE WILL BE IMPACTED BY THIS SYSTEM LATE IN THE WEEK AND INTO THE WEEKEND. DEEP LAYERED RIDGING BUILDS OHD TUE WITH THE AXIS SLIDING ACROSS THE AREA DURING THE AFTN. A WEAK COLD FRONT ASSOCIATED WITH A SHORTWAVE MOVING THROUGH SE CANADA MOVES INTO THE AREA LATE TUE NIGHT/WED MORNING AND IS FORECAST TO WASH OUT OVER US DURING THE DAY WED. A BROAD RIDGE THEN DEVELOPS OVER THE EASTERN US AS A TROUGH DIGS OVER THE WEST. AT THE SFC...A FEW SHOWERS WILL BE POSSIBLE AS THE COLD FRONT APPROACHES TUE NIGHT. INCREASING ISENTROPIC LIFT IN A WAA PATTERN COULD PROMOTE A FEW MORE ON WED...THEREFORE HAVE ADDED CHC POPS TO THE FORECAST...MAINLY WESTERN HALF OF THE CWA. THE LATTER HALF OF THE WEEK IS WHERE THE FORECAST IS UNCERTAIN DUE TO THE SYSTEM MOVING THROUGH THE PLAINS AND INTO SE CANADA ON SAT. CANADIAN HIGH PRES BUILDS IN FROM THE N ON THU WHICH MAY SUPPRESS ANY WAA RAINS TO THE S. HAVE TRIED TO TREND IN THIS DIRECTION WITH THE POPS THU NIGHT. FRI MAY END UP BEING DRY IF THIS TREND CONTINUES UNTIL THE COLD FRONT ASSOCIATED WITH THE LOW MOVES CLOSER. THERE ARE IMPLICATIONS OF SECONDARY LOW DEVELOPMENT S OF LI FRI NIGHT. THE EC IS MUCH FASTER WITH THE FROPA ON SAT WITH DRY CONDS RETURNING BY AFTN. THE GFS KEEPS IT WET THROUGH THE DAY. TEMPERATURES WILL BE AT OR ABOVE NORMAL LEVELS THROUGH THE PERIOD. && .AVIATION /02Z MONDAY THROUGH FRIDAY/... LOW PRESSURE SOUTH OF LONG ISLAND THIS EVENING WILL SLOWLY MOVE EAST THROUGH MONDAY. STRONG NORTHERLY SFC FLOW PREVAILS AS THE LOW SLOWLY PULLS AWAY. RAIN ENDS FROM WEST TO EAST IN THE MORNING AND CONDITIONS IMPROVE TO VFR BY AFTERNOON. UNCERTAINTY EXISTS IN THE TAFS THIS EVENING AS CIGS SIT AROUND 1000 FT. EXPECT FAIRLY STEADY CONDITIONS THROUGH THE OVERNIGHT. RAIN WILL MOVE BACK IN OVERNIGHT...BUT NO SIGNIFICANT CHANGE IN FLIGHT CONDITIONS ARE EXPECTED. FOR THE NY METRO...A HIGH CONFIDENCE WIND FCST WITH ASOS GUSTS IN EXCESS OF 30 KT ON MONDAY MOST OF THE DAY. .OUTLOOK FOR 00Z MONDAY THROUGH FRIDAY... .MON NGT-FRI...MAINLY VFR. && .MARINE... SCA REMAINS UP FOR ALL WATERS WITH SEAS RANGING FROM 10-13 FT AND WINDS GUSTING AROUND 30 KT THROUGH MONDAY. THERE IS THE POTENTIAL FOR GUSTS TO REACH MINIMAL GALE FROM TIME TO TIME OVERNIGHT THROUGH MON...HOWEVER DON`T FEEL IT WILL LAST LONG ENOUGH TO ISSUE A GALE WARNING. WINDS/SEAS SUBSIDE TO SUB-SCA CRITERIA MONDAY EVENING...BUT OCEAN SEAS MAY CONTINUE TO AVERAGE 4-6 FT THROUGH MONDAY NIGHT. SCA MAY LINGER ON THE EASTERN OCEAN WATERS INTO TUE...OTHERWISE A WEAK PRES GRADIENT ACROSS THE AREA WILL FAVOR TRANQUIL CONDS. AN INCREASING ELY FLOW FRI NIGHT MAY BRING SEAS TO SCA LEVELS BY SAT MORNING. && .HYDROLOGY... 1/4 TO 1/2 INCH OF QPF EXPECTED OVERNIGHT INTO MONDAY MORNING. RIVERS NOT EXPECTED TO RISE SIGNIFICANTLY. NO SIGNIFICANT PCPN EXPECTED BEFORE WEEKS END. && .TIDES/COASTAL FLOODING... DUE TO HIGH ASTRONOMICAL TIDES WITH A NEW MOON AND NEARBY LOW PRESSURE SYSTEM...TIDES ARE SLIGHTLY ELEVATED. TIDES WILL APPROACH MINOR COASTAL FLOOD BENCHMARKS WITH THE OVERNIGHT HIGH TIDE. THIS IS OCCURRING IN THE HARBOR AND ALONG THE OCEAN AS OF 01-02 UTC. HIGH TIDE ON LI SOUND IS AROUND 04 UTC. NO SPECIAL PRODUCTS ARE PLANNED. && .EQUIPMENT... THE NOAA WEATHER RADIO TRANSMITTER THAT SERVES THE NEW YORK CITY METROPOLITAN AREA IS CURRENTLY BROADCASTING. THE TRANSMITTER IS CURRENTLY BEING TESTED TO DETERMINE IF RADIO FREQUENCY INTERFERENCE CONTINUES ON THE U.S. COAST GUARD CHANNEL 16 TRANSMITTER FOR INTERNATIONAL DISTRESS...SAFETY AND RESCUE. FOR MORE INFORMATION SEE THE FOLLOWING PUBLIC INFORMATION STATEMENT (ALL LOWER CASE): WWW.WEATHER.GOV/OKX/NYCNWRUPDATE && .OKX WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. NJ...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT MONDAY FOR ANZ330-335-338- 340-345. SMALL CRAFT ADVISORY UNTIL 6 AM EDT TUESDAY FOR ANZ350-353-355. && $$ SYNOPSIS...24/MPS NEAR TERM...24/TONGUE SHORT TERM...24/MPS LONG TERM...24 AVIATION...TONGUE MARINE...24/MPS HYDROLOGY...24/MPS TIDES/COASTAL FLOODING... EQUIPMENT...
AREA FORECAST DISCUSSION
NWS TAUNTON MA
1003 PM EDT SUN MAR 30 2014 .SYNOPSIS... LOW PRES OFF ATLANTIC CITY NJ WILL PASS SOUTH OF NEW ENGLAND TONIGHT AND OUT TO SEA MONDAY AND MONDAY NIGHT. THIS WILL BRING LIGHT RAIN AND DRIZZLE TO SOUTHERN NEW ENGLAND TONIGHT. COLDER AIR DRAWN SOUTH BY INCREASING WINDS WILL CHANGE THE PRECIPITATION TO A WINTRY MIX NORTH AND WEST OF BOSTON. DRY AND MILDER WEATHER IS EXPECTED TUESDAY THROUGH THE END OF THE WEEK. UNSETTLED WEATHER RETURNS FRIDAY NIGHT INTO SATURDAY AS LOW PRESSURE MOVES INTO THE REGION. && .NEAR TERM /UNTIL 6 AM MONDAY MORNING/... 10 PM UPDATE...SHOWERS ACROSS RHODE ISLAND AND ADJACENT PARTS OF MASSACHUSETTS AND CONNECTICUT WILL CONTINUE OVER THE NEXT FEW HOURS. HAVE FILLED IN MORE THAN ORIGINALLY EXPECTED SO HAVE UPDATED POPS TO BETTER REFLECT THIS TREND. USED A BLEND OF THE LATEST NAM AND HRRR THROUGH 06Z FOR THE POPS. AT THIS POINT...SHOWERS ARE PRODUCING GENERALLY LESS THAN A TENTH OF AN INCH OF RAIN PER HOUR...THOUGH A FEW HEAVIER SHOWERS MAY RESULT IN UP TO A THIRD OF AN INCH PER HOUR. PREVIOUS DISCUSSION... LOW PRESSURE ALONG THE NJ COAST WILL MOVE EAST AND PASS SOUTH OF NEW ENGLAND TONIGHT. DEEPER MOISTURE NORTH AND WEST OF THE CENTER WILL MOVE ACROSS NEW ENGLAND DURING THE NIGHT AND BE SUFFICIENT FOR A PERIOD OF PRECIPITATION. THE LACK OF A DEEP LIFT MECHANISM AND LACK OF TROPICAL CONNECTION SUGGEST MUCH LIGHTER RAIN THAN LAST NIGHT. WE WILL ALLOW THE EXISTING FLOOD WATCH TO CONTINUE TO EXPIRATION AT 8 PM...THIS WILL ALLOW EXISTING RAIN WATER TO WORK ITS WAY THROUGH THE SYSTEM. TEMPERATURE PROFILES ARE INITIALLY SUFFICIENT FOR RAIN. BUT COLDER AIR WILL BE DRAWN SOUTH BY NORTH WINDS FEEDING TOWARD THE LOW. THIS WILL INITIALLY SUPPORT A PERIOD OF SLEET OR FREEZING RAIN. CAN/T RULE OUT A PERIOD OF SNOW IN THE HILLS OF NORTHERN WORCESTER COUNTY OR THE BERKSHIRES...BUT THE LINGERING WARM AIR FORECAST AT 850 MB AND 800 MB WORKS AGAINST THIS. ICE AMOUNTS ARE FORECAST AT 1/4" OR LESS...AND LINE UP WITH THE EXISTING WINTER WEATHER ADVISORY. NO CHANGES TO THIS HEADLINE. THE HEADLINE COVERS SRN NH WEST OF MANCHESTER AND NASHUA...NORTHERN WORCESTER COUNTY...FRANKLIN CO...AND THE EAST SLOPES OF THE BERKS. WINDS WILL ALSO BE A FACTOR. SURFACE OBS SHOW WIND GUSTS TO 31 KNOTS AT BVY AND 38 KNOTS OVER MASSACHUSETTS BAY. MODEL DATA SHOWS NORTH NORTHEAST WINDS OF 35-40 KNOTS AROUND 2000 FEET AGL...WE MOVED GUSTS CLOSER TO THIS VALUE. WE USED A BLEND OF MODELS INCLUDING THE RAP...AND BUMPED VALUES UP ABOUT 5 KNOTS. && .SHORT TERM /6 AM MONDAY MORNING THROUGH MONDAY NIGHT/... LOW PRESSURE MOVES SOUTH OF NOVA SCOTIA. STILL A TIGHT PRESSURE GRADIENT OVER SOUTHERN NEW ENGLAND WITH PRESSURE RISES OF 1-2 MB/HOUR. WINDS ALOFT SHOW A GUST POTENTIAL OF 25-30 KNOTS OVER LAND...AND 30-40 KNOTS ALONG THE EAST MASS COAST/CAPE/ISLANDS. CLOSED UPPER LOW SLOWLY MOVES EAST DURING THE DAY AND NIGHT. CLOUDS ASSOCIATED WITH THE UPPER LOW WILL LINGER OVER US MUCH OF THE DAY...WITH A SLOW CLEARING FROM WEST TO EAST MONDAY AFTERNOON AND NIGHT. THE PRESSURE GRADIENT RELAXES MONDAY NIGHT...SO EXPECT DIMINISHING WINDS FROM WEST TO EAST OVERNIGHT. TEMPS COME FROM A BLEND OF MODEL DATA. && .LONG TERM /TUESDAY THROUGH SUNDAY/... HIGHLIGHTS... * MAINLY DRY AND NEAR SEASONABLE THROUGH THE END OF THE WEEK * UNSETTLED WEATHER RETURNS FOR THE FIRST HALF OF NEXT WEEKEND OVERVIEW... MEDIUM RANGE GUIDANCE IN GOOD AGREEMENT ON THE OVERALL PATTERN THROUGH THE EXTENDED PERIOD...ALTHOUGH THERE ARE SOME DIFFERENCES IN THE DETAILS AT THE SURFACE TOWARD THE END OF THE PERIOD AS MID LEVEL TROF APPROACHES FROM THE GT LAKES. OVERALL IT LOOKS MAINLY DRY AND SEASONABLE THROUGH THE END OF THE WEEK WITH A LOW PROB OF A FEW SHOWERS WED WITH A FROPA. COULD SEE A FEW DAYS WITH ABOVE NORMAL TEMPS WED/THU THEN TRENDING COOLER BY FRI AS LOW LEVEL NE FLOW DEVELOPS. A PERIOD OF UNSETTLED WEATHER APPEARS LIKELY FRI NIGHT INTO SAT AS COMPLEX SYSTEM MOVES INTO THE REGION BUT OBVIOUSLY LOW CONFIDENCE ON THE DETAILS. IT DOES APPEAR MOST OF THE PRECIP WILL BE RAIN BUT THERE COULD BE SOME WINTRY PRECIP IN THE INTERIOR. TUESDAY... SHARP MID LEVEL AND SFC RIDGE BUILDS INTO NEW ENG FROM THE WEST. CLOUDS MAY STILL BE LINGERING ACROSS E COASTAL MA AND ESPECIALLY CAPE/ISLANDS IN THE MORNING...OTHERWISE PT-MOSUNNY SKIES EXPECTED. STILL BREEZY IN THE MORNING ESPECIALLY CAPE/ISLANDS THEN DIMINISHING WIND THROUGH THE DAY. MILDEST TEMPS INTO THE 50S WILL BE IN THE CT VALLEY WITH COOLEST IN THE LOW/MID 40S E COASTAL MA AND CAPE/ISLANDS. WEDNESDAY... GUIDANCE INDICATES A WEAK COLD FRONT MOVING INTO SNE. A DEEP MOISTURE PLUME FROM THE WEST MOVES INTO THE REGION...ESPECIALLY SOUTH OF THE MASS PIKE WHICH MAY BRING A FEW SHOWERS. TEMPS NEAR OR SLIGHTLY ABOVE NORMAL WITH LIGHT WINDS. THURSDAY INTO FRIDAY... GENERALLY DRY DURING THIS PERIOD AS HIGH PRES BUILDS TO THE NORTH...BUT MOISTURE AHEAD OF NEXT SYSTEM WILL BE APPROACHING LATER FRI. WE KEPT THE FORECAST DRY AS HIGH PRES SHOULD SLOW ONSET OF PRECIP. TEMPS NEAR OR SLIGHTLY ABOVE NORMAL THU BUT COOLING FRI...ESPECIALLY EAST AS NE FLOW BECOMES ESTABLISHED FRIDAY NIGHT INTO SATURDAY... THIS LOOKS TO BE THE MOSTLY LIKELY PERIOD OF UNSETTLED WEATHER AS COMPLEX SYSTEM APPROACHES FROM THE WEST BUT DETAILS UNCERTAIN. PRIMARY LOW LIFTS NE ACROSS THE LAKES WITH A SECONDARY LOW DEVELOPING NEAR THE S COAST. PTYPE MAINLY RAIN...BUT THERE IS SOME COLDER AIR BELOW 850 MB WHICH MAY SUPPORT SOME MIXED WINTRY PRECIP ACROSS DISTANT INTERIOR. SUNDAY... LATEST GFS/ECMWF MOVE SYSTEM INTO THE MARITIMES WITH DRIER NW FLOW DEVELOPING SO IT LOOKS DRY FOR NOW. && .AVIATION /02Z MONDAY THROUGH FRIDAY/... LOW...LESS THAN 30 PERCENT. MODERATE...30 TO 60 PERCENT. HIGH...GREATER THAN 60 PERCENT. MODERATE CONFIDENCE THROUGH MONDAY NIGHT. TONIGHT...COASTAL LOW PRESSURE PASSES SOUTH OF NEW ENGLAND BUT BRINGS ANOTHER AREA OF RAIN INTO OUR AREA. IT WILL ALSO DRAW COLDER AIR SOUTH...WHICH WILL CHANGE THE RAIN TO FREEZING RAIN AND SLEET IN SOUTHWEST NH AND NORTHERN MASS. THIS AREA INCLUDES MHT AND ORH. FARTHER SOUTH WE EXPECT MAINLY LIGHT RAIN. IFR/LIFR CONDITIONS WITH A GUSTY NORTH-NORTHEAST WIND...WITH MVFR/IFR CT VALLEY. MONDAY...LIGHT PRECIPITATION WILL TAPER OFF. EXPECT IFR CONDITIONS IMPROVING TO VFR IN THE CT VALLEY AND POSSIBLY TO ORH. IFR WILL IMPROVE TO MVFR IN RI/EASTERN MASS/SRN NH. DEPENDING ON HOW SLOWLY THE STORM MOVES EAST...IFR COULD LINGER AT HYA AND ACK AND THE OUTER CAPE. INCREASING NORTH TO NORTHWEST WINDS DURING THE DAY. WINDS AT 2000 FEET AGL SHOULD REACH 35 KNOTS EAST OF WORCESTER AND 40-50 KNOTS ALONG THE EAST MASSACHUSETTS COAST. THIS WOULD LEAD TO LOW LEVEL WIND SHEAR CONCERNS...BOS/FMH/HYA/ACK WOULD BE MOST LIKELY TO EXPERIENCE THIS. MONDAY NIGHT...STRONG GUSTY NORTH WINDS ALONG THE MASS EAST COAST SURFACE AND ALOFT...THESE WILL DIMINISH OVERNIGHT. LINGERING MVFR CIGS ON THE CAPE AND ISLANDS...VFR AT BOS-PVD AND NORTH/WEST. KBOS TERMINAL...MODERATE CONFIDENCE IN TAF. KBDL TERMINAL...MODERATE CONFIDENCE IN TAF. LOW RISK OF A FEW HOURS OF FZRA TONIGHT INTO MON AM. OUTLOOK...TUESDAY THROUGH FRIDAY... TUESDAY...MODERATE CONFIDENCE. AREAS OF LINGERING MVFR CIGS IN THE MORNING ACROSS E MA AND ESPECIALLY CAPE/ISLANDS...OTHERWISE VFR. N WIND GUSTS 25-30 KT CAPE/ISLANDS IN THE MORNING. WEDNESDAY THROUGH FRIDAY...MODERATE CONFIDENCE. MAINLY VFR. LOW PROBABILITY OF BRIEF MVFR CONDITIONS IN SHOWERS DURING WED. && .MARINE... FORECASTER CONFIDENCE LEVELS... LOW...LESS THAN 30 PERCENT. MODERATE...30 TO 60 PERCENT. HIGH...GREATER THAN 60 PERCENT. MODERATE CONFIDENCE THROUGH MONDAY NIGHT. TONIGHT... STRONG NORTH-NORTHEAST WINDS ARE MOVING SOUTH THROUGH CAPE ANN AND THE WATERS JUST OFFSHORE. THIS WILL CONTINUE TO SHIFT SOUTH OVERNIGHT. WINDS IN THIS AREA HAVE FREQUENT GUSTS OF 30-35 KNOTS. WE HAVE CONVERTED THE GALE WATCH TO A GALE WARNING...AND EXPANDED IT INTO BOSTON HARBOR AND NARRAGANSETT BAY. BUILDING SEAS IN THE EXPOSED WATERS WITH HEIGHTS OF 5-10 FEET. VSBY REDUCED IN RAIN AND FOG. MONDAY... NORTH WINDS CONTINUE AT 20-30 KNOTS SUSTAINED AND GUSTS 35-40 KNOTS. ROUGH SEAS CONTINUE WITH 5-10 FEET IN THE EXPOSED WATERS...AND 10-15 FEET NEAR STELLWAGEN BANK. RAIN/FOG/POOR VSBYS TAPER OFF IN THE AFTERNOON. MONDAY NIGHT... DIMINISHING WINDS AND SEAS BUT WITH GALES CONTINUING ON THE EASTERN MASS WATERS THROUGH THE NIGHT...AND 10-15 FOOT SEAS EAST OF OUTER CAPE COD. OUTLOOK...TUESDAY THROUGH FRIDAY... TUESDAY...HIGH CONFIDENCE. STILL MAY SEE MARGINAL GALE FORCE WINDS ON THE EASTERN OUTER WATERS TUE MORNING...BUT TREND WILL BE DIMINISHING WIND AND SEAS. 15 FT SEAS POSSIBLE OVER WATERS EAST OF CAPE COD IN THE MORNING. WEDNESDAY THROUGH FRIDAY...HIGH CONFIDENCE. WINDS BELOW SCA THRESHOLDS THROUGH THE PERIOD. WESTERLY WINDS WED BECOMING NORTHERLY THU THEN E/NE FRIDAY. LINGERING SCA SEAS WED MORNING OVER THE EASTERN WATERS WILL SUBSIDE. && .HYDROLOGY... RAINFALL RANGED FROM 2 TO 5 INCHES ACROSS SOUTHERN NEW ENGLAND. SOME OF THE HIGHEST TOTALS WERE IN RI AND SOUTHEAST MA...WHERE A HANDFUL OF REPORTS OF 5 PLUS INCHES OF RAIN WERE RECEIVED. THE BIGGEST OF THE FLOOD EVENTS WAS URBAN FLASH FLOODING IN THE FALL RIVER/NEW BEDFORD AREA AND VARIOUS COMMUNITIES IN SOUTHEAST MA/RI. IN PORTIONS OF THIS AREA...URBAN AND POOR DRAINAGE FLOOD WATERS WILL LIKELY TAKE INTO THIS EVENING TO FULLY SUBSIDE. MANY SMALL STREAMS AND RIVERS HAVE CRESTED BUT OTHERS ARE STILL RISING...SO CONTINUING WITH FLOOD WATCH THROUGH 8 PM AND CONTINUING TO MONITOR. SEVERAL RIVER FORECAST POINTS ARE IN FLOOD OR FORECAST TO RISE ABOVE FLOOD STAGE. THESE INCLUDE THE ASSABET RIVER AT MAYNARD...PAWTUXET RIVER IN CRANSTON...AND THE PAWCATUCK RIVER AT WOOD RIVER JUNCTION AND WESTERLY. PLEASE SEE THE LATEST FLOOD STATEMENTS FOR UPDATES...OR GO TO THE PAGE HTTP:/WATER.WEATHER.GOV/AHPS2/FORECASTS.PHP?WFO=BOX FOR SMALL STREAMS...THERE IS THE POSSIBILITY OF PURCHADE BROOK FLOODING WOLOSKI PARK IN MIDDLEBORO...WHICH WOULD ISOLATE SOME HOMES. AT THIS TIME...8 PM STILL SEEMS TO BE A REASONABLE EXPIRATION TIME FOR THE FLOOD WATCH AS THE HEAVY RAIN IS LONG GONE AND WE ARE MAINLY MONITORING RUNOFF/DRAINAGE AT THIS TIME. LOOKING BEYOND TONIGHT INTO EARLY NEXT WEEK...IT MAY BE A CLOSE CALL FOR THE RIVER FORECAST POINTS ON THE LOWEST END OF THE CONNECTICUT RIVER. AT MIDDLE HADDAM...THE LATEST FORECAST CREST IS JUST SHORT OF FLOOD STAGE FOR THIS TUESDAY. && .TIDES/COASTAL FLOODING... ONLY SOME SPLASHOVER OCCURRED AT THE TIME OF THE HIGH TIDE SHORTLY BEFORE NOON THIS MORNING WITH A SURGE THAT APPROACHED 1 FOOT. HOWEVER...NORTHEAST TO NORTH WINDS WERE INCREASING THIS EVENING AND WILL CONTINUE TO INCREASE TO GALE FORCE ALONG THE MA EAST COAST BY MONDAY AFTERNOON. WE ARE EXPECTING THAT THIS WILL GENERATE A 1 FOOT SURGE AROUND MIDNIGHT AND UP TO A 1.5 FOOT SURGE AROUND NOON ON MONDAY. SEAS OFFSHORE WILL BE BUILDING AS HIGH AS 8 TO 12 FEET BY MONDAY AFTERNOON. AT THAT TIME...WINDS WILL HAVE SHIFTED TO DUE NORTH WHICH WILL MAKE THE MAIN FOCUS OVER THE SOUTH SHORE AND CAPE COD BAY. SO...EXPECTING MINOR COASTAL FLOODING AROUND MIDNIGHT ON THE EAST COAST AND AROUND NOON FROM SCITUATE TO CAPE COD AROUND NOON MONDAY. IN ADDITION...THERE WILL BE MINOR TO POSSIBLY MODERATE BEACH EROSION THROUGH MONDAY ALONG THE MA EAST COAST. && .BOX WATCHES/WARNINGS/ADVISORIES... CT...NONE. MA...WINTER WEATHER ADVISORY UNTIL 10 AM EDT MONDAY FOR MAZ002>004- 008-009-026. COASTAL FLOOD ADVISORY UNTIL 3 AM EDT MONDAY FOR MAZ007-015- 016-019. COASTAL FLOOD ADVISORY FROM 10 AM TO 3 PM EDT MONDAY FOR MAZ019-022. NH...WINTER WEATHER ADVISORY UNTIL 10 AM EDT MONDAY FOR NHZ011-015. RI...NONE. MARINE...GALE WARNING FROM 6 AM MONDAY TO 6 AM EDT TUESDAY FOR ANZ231>234. GALE WARNING FROM NOON TO 11 PM EDT MONDAY FOR ANZ230-236. GALE WARNING FROM 6 AM MONDAY TO 3 AM EDT TUESDAY FOR ANZ235- 237. GALE WARNING UNTIL 10 AM EDT TUESDAY FOR ANZ250-251. GALE WARNING FROM 6 AM MONDAY TO 10 AM EDT TUESDAY FOR ANZ254>256. && $$ SYNOPSIS...WTB/KJC NEAR TERM...WTB/KJC/RLG SHORT TERM...WTB LONG TERM...KJC AVIATION...WTB/KJC MARINE...WTB/KJC HYDROLOGY... TIDES/COASTAL FLOODING...
AREA FORECAST DISCUSSION
NWS TAUNTON MA
711 PM EDT SUN MAR 30 2014 .SYNOPSIS... LOW PRESSURE OFF ATLANTIC CITY NJ WILL PASS SOUTH OF NEW ENGLAND TONIGHT AND OUT TO SEA MONDAY AND MONDAY NIGHT. THIS WILL BRING LIGHT RAIN AND DRIZZLE TO SOUTHERN NEW ENGLAND TONIGHT. COLDER AIR DRAWN SOUTH BY INCREASING WINDS WILL CHANGE THE PRECIPITATION TO A WINTRY MIX NORTH AND WEST OF BOSTON. DRY AND MILDER WEATHER IS EXPECTED TUESDAY THROUGH THE END OF THE WEEK. UNSETTLED WEATHER RETURNS FRIDAY NIGHT INTO SATURDAY AS LOW PRESSURE MOVES INTO THE REGION. && .NEAR TERM /UNTIL 6 AM MONDAY MORNING/... 710 PM UPDATE... NUMEROUS SHOWERS HAVE FILLED IN ACROSS SNE AND ARE LIFTING N ACROSS THE REGION AS THEY ROTATE AROUND MID LEVEL LOW TO THE SOUTH. HRRR INDICATING THESE SHOWERS WILL ROTATE ACROSS N CT AND CENTRAL/W MA THROUGH THE EVENING. GOOD MID LEVEL COOLING TONIGHT SO SOME OF THESE SHOWERS COULD PRODUCE LOCALLY HEAVY RAINFALL. UPDATED POPS TO REFLECT CURRENT TRENDS AND HRRR FORECAST. PREVIOUS DISCUSSION... LOW PRESSURE ALONG THE NJ COAST WILL MOVE EAST AND PASS SOUTH OF NEW ENGLAND TONIGHT. DEEPER MOISTURE NORTH AND WEST OF THE CENTER WILL MOVE ACROSS NEW ENGLAND DURING THE NIGHT AND BE SUFFICIENT FOR A PERIOD OF PRECIPITATION. THE LACK OF A DEEP LIFT MECHANISM AND LACK OF TROPICAL CONNECTION SUGGEST MUCH LIGHTER RAIN THAN LAST NIGHT. WE WILL ALLOW THE EXISTING FLOOD WATCH TO CONTINUE TO EXPIRATION AT 8 PM...THIS WILL ALLOW EXISTING RAIN WATER TO WORK ITS WAY THROUGH THE SYSTEM. TEMPERATURE PROFILES ARE INITIALLY SUFFICIENT FOR RAIN. BUT COLDER AIR WILL BE DRAWN SOUTH BY NORTH WINDS FEEDING TOWARD THE LOW. THIS WILL INITIALLY SUPPORT A PERIOD OF SLEET OR FREEZING RAIN. CAN/T RULE OUT A PERIOD OF SNOW IN THE HILLS OF NORTHERN WORCESTER COUNTY OR THE BERKSHIRES...BUT THE LINGERING WARM AIR FORECAST AT 850 MB AND 800 MB WORKS AGAINST THIS. ICE AMOUNTS ARE FORECAST AT 1/4" OR LESS...AND LINE UP WITH THE EXISTING WINTER WEATHER ADVISORY. NO CHANGES TO THIS HEADLINE. THE HEADLINE COVERS SRN NH WEST OF MANCHESTER AND NASHUA...NORTHERN WORCESTER COUNTY...FRANKLIN CO...AND THE EAST SLOPES OF THE BERKS. WINDS WILL ALSO BE A FACTOR. SURFACE OBS SHOW WIND GUSTS TO 31 KNOTS AT BVY AND 38 KNOTS OVER MASSACHUSETTS BAY. MODEL DATA SHOWS NORTH NORTHEAST WINDS OF 35-40 KNOTS AROUND 2000 FEET AGL...WE MOVED GUSTS CLOSER TO THIS VALUE. WE USED A BLEND OF MODELS INCLUDING THE RAP...AND BUMPED VALUES UP ABOUT 5 KNOTS. && .SHORT TERM /6 AM MONDAY MORNING THROUGH MONDAY NIGHT/... LOW PRESSURE MOVES SOUTH OF NOVA SCOTIA. STILL A TIGHT PRESSURE GRADIENT OVER SOUTHERN NEW ENGLAND WITH PRESSURE RISES OF 1-2 MB/HOUR. WINDS ALOFT SHOW A GUST POTENTIAL OF 25-30 KNOTS OVER LAND...AND 30-40 KNOTS ALONG THE EAST MASS COAST/CAPE/ISLANDS. CLOSED UPPER LOW SLOWLY MOVES EAST DURING THE DAY AND NIGHT. CLOUDS ASSOCIATED WITH THE UPPER LOW WILL LINGER OVER US MUCH OF THE DAY...WITH A SLOW CLEARING FROM WEST TO EAST MONDAY AFTERNOON AND NIGHT. THE PRESSURE GRADIENT RELAXES MONDAY NIGHT...SO EXPECT DIMINISHING WINDS FROM WEST TO EAST OVERNIGHT. TEMPS COME FROM A BLEND OF MODEL DATA. && .LONG TERM /TUESDAY THROUGH SUNDAY/... HIGHLIGHTS... * MAINLY DRY AND NEAR SEASONABLE THROUGH THE END OF THE WEEK * UNSETTLED WEATHER RETURNS FOR THE FIRST HALF OF NEXT WEEKEND OVERVIEW... MEDIUM RANGE GUIDANCE IN GOOD AGREEMENT ON THE OVERALL PATTERN THROUGH THE EXTENDED PERIOD...ALTHOUGH THERE ARE SOME DIFFERENCES IN THE DETAILS AT THE SURFACE TOWARD THE END OF THE PERIOD AS MID LEVEL TROF APPROACHES FROM THE GT LAKES. OVERALL IT LOOKS MAINLY DRY AND SEASONABLE THROUGH THE END OF THE WEEK WITH A LOW PROB OF A FEW SHOWERS WED WITH A FROPA. COULD SEE A FEW DAYS WITH ABOVE NORMAL TEMPS WED/THU THEN TRENDING COOLER BY FRI AS LOW LEVEL NE FLOW DEVELOPS. A PERIOD OF UNSETTLED WEATHER APPEARS LIKELY FRI NIGHT INTO SAT AS COMPLEX SYSTEM MOVES INTO THE REGION BUT OBVIOUSLY LOW CONFIDENCE ON THE DETAILS. IT DOES APPEAR MOST OF THE PRECIP WILL BE RAIN BUT THERE COULD BE SOME WINTRY PRECIP IN THE INTERIOR. TUESDAY... SHARP MID LEVEL AND SFC RIDGE BUILDS INTO NEW ENG FROM THE WEST. CLOUDS MAY STILL BE LINGERING ACROSS E COASTAL MA AND ESPECIALLY CAPE/ISLANDS IN THE MORNING...OTHERWISE PT-MOSUNNY SKIES EXPECTED. STILL BREEZY IN THE MORNING ESPECIALLY CAPE/ISLANDS THEN DIMINISHING WIND THROUGH THE DAY. MILDEST TEMPS INTO THE 50S WILL BE IN THE CT VALLEY WITH COOLEST IN THE LOW/MID 40S E COASTAL MA AND CAPE/ISLANDS. WEDNESDAY... GUIDANCE INDICATES A WEAK COLD FRONT MOVING INTO SNE. A DEEP MOISTURE PLUME FROM THE WEST MOVES INTO THE REGION...ESPECIALLY SOUTH OF THE MASS PIKE WHICH MAY BRING A FEW SHOWERS. TEMPS NEAR OR SLIGHTLY ABOVE NORMAL WITH LIGHT WINDS. THURSDAY INTO FRIDAY... GENERALLY DRY DURING THIS PERIOD AS HIGH PRES BUILDS TO THE NORTH...BUT MOISTURE AHEAD OF NEXT SYSTEM WILL BE APPROACHING LATER FRI. WE KEPT THE FORECAST DRY AS HIGH PRES SHOULD SLOW ONSET OF PRECIP. TEMPS NEAR OR SLIGHTLY ABOVE NORMAL THU BUT COOLING FRI...ESPECIALLY EAST AS NE FLOW BECOMES ESTABLISHED FRIDAY NIGHT INTO SATURDAY... THIS LOOKS TO BE THE MOSTLY LIKELY PERIOD OF UNSETTLED WEATHER AS COMPLEX SYSTEM APPROACHES FROM THE WEST BUT DETAILS UNCERTAIN. PRIMARY LOW LIFTS NE ACROSS THE LAKES WITH A SECONDARY LOW DEVELOPING NEAR THE S COAST. PTYPE MAINLY RAIN...BUT THERE IS SOME COLDER AIR BELOW 850 MB WHICH MAY SUPPORT SOME MIXED WINTRY PRECIP ACROSS DISTANT INTERIOR. SUNDAY... LATEST GFS/ECMWF MOVE SYSTEM INTO THE MARITIMES WITH DRIER NW FLOW DEVELOPING SO IT LOOKS DRY FOR NOW. && .AVIATION /00Z MONDAY THROUGH FRIDAY/... LOW...LESS THAN 30 PERCENT. MODERATE...30 TO 60 PERCENT. HIGH...GREATER THAN 60 PERCENT. MODERATE CONFIDENCE THROUGH MONDAY NIGHT. TONIGHT...COASTAL LOW PRESSURE PASSES SOUTH OF NEW ENGLAND BUT BRINGS ANOTHER AREA OF RAIN INTO OUR AREA. IT WILL ALSO DRAW COLDER AIR SOUTH...WHICH WILL CHANGE THE RAIN TO FREEZING RAIN AND SLEET IN SOUTHWEST NH AND NORTHERN MASS. THIS AREA INCLUDES MHT AND ORH. FARTHER SOUTH WE EXPECT MAINLY LIGHT RAIN. IFR/LIFR CONDITIONS WITH A GUSTY NORTH-NORTHEAST WIND...WITH MVFR/IFR CT VALLEY. MONDAY...LIGHT PRECIPITATION WILL TAPER OFF. EXPECT IFR CONDITIONS IMPROVING TO VFR IN THE CT VALLEY AND POSSIBLY TO ORH. IFR WILL IMPROVE TO MVFR IN RI/EASTERN MASS/SRN NH. DEPENDING ON HOW SLOWLY THE STORM MOVES EAST...IFR COULD LINGER AT HYA AND ACK AND THE OUTER CAPE. INCREASING NORTH TO NORTHWEST WINDS DURING THE DAY. WINDS AT 2000 FEET AGL SHOULD REACH 35 KNOTS EAST OF WORCESTER AND 40-50 KNOTS ALONG THE EAST MASSACHUSETTS COAST. THIS WOULD LEAD TO LOW LEVEL WIND SHEAR CONCERNS...BOS/FMH/HYA/ACK WOULD BE MOST LIKELY TO EXPERIENCE THIS. MONDAY NIGHT...STRONG GUSTY NORTH WINDS ALONG THE MASS EAST COAST SURFACE AND ALOFT...THESE WILL DIMINISH OVERNIGHT. LINGERING MVFR CIGS ON THE CAPE AND ISLANDS...VFR AT BOS-PVD AND NORTH/WEST. KBOS TERMINAL...MODERATE CONFIDENCE IN TAF. KBDL TERMINAL...MODERATE CONFIDENCE IN TAF. LOW RISK OF A FEW HOURS OF FZRA TONIGHT INTO MON AM. OUTLOOK...TUESDAY THROUGH FRIDAY... TUESDAY...MODERATE CONFIDENCE. AREAS OF LINGERING MVFR CIGS IN THE MORNING ACROSS E MA AND ESPECIALLY CAPE/ISLANDS...OTHERWISE VFR. N WIND GUSTS 25-30 KT CAPE/ISLANDS IN THE MORNING. WEDNESDAY THROUGH FRIDAY...MODERATE CONFIDENCE. MAINLY VFR. LOW PROBABILITY OF BRIEF MVFR CONDITIONS IN SHOWERS DURING WED. && .MARINE... FORECASTER CONFIDENCE LEVELS... LOW...LESS THAN 30 PERCENT. MODERATE...30 TO 60 PERCENT. HIGH...GREATER THAN 60 PERCENT. MODERATE CONFIDENCE THROUGH MONDAY NIGHT. TONIGHT... STRONG NORTH-NORTHEAST WINDS ARE MOVING SOUTH THROUGH CAPE ANN AND THE WATERS JUST OFFSHORE. THIS WILL CONTINUE TO SHIFT SOUTH OVERNIGHT. WINDS IN THIS AREA HAVE FREQUENT GUSTS OF 30-35 KNOTS. WE HAVE CONVERTED THE GALE WATCH TO A GALE WARNING...AND EXPANDED IT INTO BOSTON HARBOR AND NARRAGANSETT BAY. BUILDING SEAS IN THE EXPOSED WATERS WITH HEIGHTS OF 5-10 FEET. VSBY REDUCED IN RAIN AND FOG. MONDAY... NORTH WINDS CONTINUE AT 20-30 KNOTS SUSTAINED AND GUSTS 35-40 KNOTS. ROUGH SEAS CONTINUE WITH 5-10 FEET IN THE EXPOSED WATERS...AND 10-15 FEET NEAR STELLWAGEN BANK. RAIN/FOG/POOR VSBYS TAPER OFF IN THE AFTERNOON. MONDAY NIGHT... DIMINISHING WINDS AND SEAS BUT WITH GALES CONTINUING ON THE EASTERN MASS WATERS THROUGH THE NIGHT...AND 10-15 FOOT SEAS EAST OF OUTER CAPE COD. OUTLOOK...TUESDAY THROUGH FRIDAY... TUESDAY...HIGH CONFIDENCE. STILL MAY SEE MARGINAL GALE FORCE WINDS ON THE EASTERN OUTER WATERS TUE MORNING...BUT TREND WILL BE DIMINISHING WIND AND SEAS. 15 FT SEAS POSSIBLE OVER WATERS EAST OF CAPE COD IN THE MORNING. WEDNESDAY THROUGH FRIDAY...HIGH CONFIDENCE. WINDS BELOW SCA THRESHOLDS THROUGH THE PERIOD. WESTERLY WINDS WED BECOMING NORTHERLY THU THEN E/NE FRIDAY. LINGERING SCA SEAS WED MORNING OVER THE EASTERN WATERS WILL SUBSIDE. && .HYDROLOGY... RAINFALL RANGED FROM 2 TO 5 INCHES ACROSS SOUTHERN NEW ENGLAND. SOME OF THE HIGHEST TOTALS WERE IN RI AND SOUTHEAST MA...WHERE A HANDFULL OF REPORTS OF 5 PLUS INCHES OF RAIN WERE RECEIVED. THE BIGGEST OF THE FLOOD EVENTS WAS URBAN FLASH FLOODING IN THE FALL RIVER/NEW BEDFORD AREA AND VARIOUS COMMUNITIES IN SOUTHEAST MA/RI. IN PORTIONS OF THIS AREA...URBAN AND POOR DRAINAGE FLOODWATERS WILL LIKELY TAKE INTO THIS EVENING TO FULLY SUBSIDE. MANY SMALL STREAMS AND RIVERS HAVE CRESTED BUT OTHERS ARE STILL RISING...SO CONTINUING WITH FLOOD WATCH THROUGH 8 PM AND CONTINUING TO MONITOR. SEVERAL RIVER FORECAST POINTS ARE IN FLOOD OR FORECAST TO RISE ABOVE FLOOD STAGE. THESE INCLUDE THE ASSABET RIVER AT MAYNARD...PAWTUXET RIVER IN CRANSTON...AND THE PAWCATUCK RIVER AT WOOD RIVER JUNCTION AND WESTERLY. PLEASE SEE THE LATEST FLOOD STATEMENTS FOR UPDATES...OR GO TO THE PAGE HTTP:/WATER.WEATHER.GOV/AHPS2/FORECASTS.PHP?WFO=BOX FOR SMALL STREAMS...THERE IS THE POSSIBILITY OF PURCHADE BROOK FLOODING WOLOSKI PARK IN MIDDLEBORO...WHICH WOULD ISOLATE SOME HOMES. AT THIS TIME...8 PM STILL SEEMS TO BE A REASONABLE EXPIRATION TIME FOR THE FLOOD WATCH AS THE HEAVY RAIN IS LONG GONE AND WE ARE MAINLY MONITORING RUNOFF/DRAINAGE AT THIS TIME. LOOKING BEYOND TONIGHT INTO EARLY NEXT WEEK...IT MAY BE A CLOSE CALL FOR THE RIVER FORECAST POINTS ON THE LOWEST END OF THE CONNECTICUT RIVER. AT MIDDLE HADDAM...THE LATEST FORECAST CREST IS JUST SHORT OF FLOOD STAGE FOR THIS TUESDAY. && .TIDES/COASTAL FLOODING... ONLY SOME SPLASHOVER OCCURRED AT THE TIME OF THE HIGH TIDE SHORTLY BEFORE NOON THIS MORNING WITH A SURGE THAT APPROACHED 1 FOOT. HOWEVER...NORTHEAST TO NORTH WINDS WERE INCREASING THIS EVENING AND WILL CONTINUE TO INCREASE TO GALE FORCE ALONG THE MA EAST COAST BY MONDAY AFTERNOON. WE ARE EXPECTING THAT THIS WILL GENERATE A 1 FOOT SURGE AROUND MIDNIGHT AND UP TO A 1.5 FOOT SURGE AROUND NOON ON MONDAY. SEAS OFFSHORE WILL BE BUILDING AS HIGH AS 8 TO 12 FEET BY MONDAY AFTERNOON. AT THAT TIME...WINDS WILL HAVE SHIFTED TO DUE NORTH WHICH WILL MAKE THE MAIN FOCUS OVER THE SOUTH SHORE AND CAPE COD BAY. SO...EXPECTING MINOR COASTAL FLOODING AROUND MIDNIGHT ON THE EAST COAST AND AROUND NOON FROM SCITUATE TO CAPE COD AROUND NOON MONDAY. IN ADDITION...THERE WILL BE MINOR TO POSSIBLY MODERATE BEACH EROSION THROUGH MONDAY ALONG THE MA EAST COAST. && .BOX WATCHES/WARNINGS/ADVISORIES... CT...FLOOD WATCH UNTIL 8 PM EDT THIS EVENING FOR CTZ002>004. MA...FLOOD WATCH UNTIL 8 PM EDT THIS EVENING FOR MAZ002>006-008>012- 026. WINTER WEATHER ADVISORY UNTIL 10 AM EDT MONDAY FOR MAZ002>004- 008-009-026. COASTAL FLOOD ADVISORY FROM 10 PM THIS EVENING TO 3 AM EDT MONDAY FOR MAZ007-015-016-019. COASTAL FLOOD ADVISORY FROM 10 AM TO 3 PM EDT MONDAY FOR MAZ019-022. NH...FLOOD WATCH UNTIL 8 PM EDT THIS EVENING FOR NHZ011-012-015. WINTER WEATHER ADVISORY UNTIL 10 AM EDT MONDAY FOR NHZ011-015. RI...FLOOD WATCH UNTIL 8 PM EDT THIS EVENING FOR RIZ001. MARINE...GALE WARNING FROM 6 AM MONDAY TO 6 AM EDT TUESDAY FOR ANZ231>234. GALE WARNING FROM NOON TO 11 PM EDT MONDAY FOR ANZ230-236. GALE WARNING FROM 6 AM MONDAY TO 3 AM EDT TUESDAY FOR ANZ235- 237. GALE WARNING UNTIL 10 AM EDT TUESDAY FOR ANZ250-251. GALE WARNING FROM 6 AM MONDAY TO 10 AM EDT TUESDAY FOR ANZ254>256. && $$ SYNOPSIS...WTB/KJC NEAR TERM...WTB/KJC SHORT TERM...WTB LONG TERM...KJC AVIATION...WTB/KJC MARINE...WTB/KJC HYDROLOGY... TIDES/COASTAL FLOODING...
AREA FORECAST DISCUSSION
NWS ALBANY NY
416 PM EDT SAT MAR 29 2014 .SYNOPSIS... AN EARLY SPRING STORM WILL BRING MODERATE TO HEAVY PRECIPITATION ACROSS THE REGION FOR THE REMAINDER OF THIS WEEKEND. TEMPERATURES WILL BECOME QUITE DIVERSE WITH THE COOLER VALUES EXPECTED ACROSS THE HIGHER TERRAIN. IN FACT...THESE COOLER TEMPERATURES WILL RESULT A WINTRY MIXTURE OF PRECIPITATION TO EVOLVE WITH SOME ACCUMULATIONS ANTICIPATED. && .NEAR TERM /UNTIL 6 AM SUNDAY MORNING/... AS OF 330 PM EDT...A FEW BREAKS OF SUNSHINE RESULTED IN HIGHER THAN EXPECTED TEMPERATURES THIS AFTERNOON WITH MOST VALLEY LOCATIONS AROUND 50F AND EVEN INTO THE TERRAIN OF THE BERKS AND SOUTHERN GREENS WHERE LOWER 50S HAVE BEEN OBSERVED. REGIONAL RADAR MOSAIC REVEALS THE LEADING EDGE OF THE RAIN SHIELD WAS APPROACHING THE MASS PIKE WITH SOLID AREA OF RAIN ALONG THE I84 CORRIDOR AND ALL OF LITCHFIELD COUNTY. THIS AREA OF RAIN WILL EXPAND AND INCREASE FROM SOUTH TO NORTH THROUGH THIS EVENING PER THE LATEST HRRR REFLECTIVITY FORECASTS. WITH RATHER MILD TEMPERATURES...MOST OF THE INITIAL ONSET OF PRECIP SHOULD BE IN THE FORM OF RAIN ACROSS THE ADIRONDACKS. THE LOW LEVEL AGEOSTROPHIC FLOW FROM THE NORTH INCREASES OVERNIGHT. LOOKING UPSTREAM THE TEMPS WERE INTO THE MID 30S WITH DEWPOINTS INTO THE MID 20S. SO NOT THAT COLD OF AN AIRMASS BUT WET BULB PROCESS COULD SEE A MIXTURE OF RAIN/SLEET/FREEZING RAIN AS WE WILL HOLD ONTO THE WINTER WEATHER ADVISORIES AT THIS TIME. CHANCES FOR WINTRY TYPE PRECIPITATION APPEARS TO BE DIMINISHING ACROSS THE GLENS FALLS REGION AS ADDITIONAL SHIFTS IN THE HEADLINES ARE POSSIBLE IF THE TRENDS CONTINUE TO WARM. AS FOR RAINFALL...IMPRESSIVE ISENTROPIC LIFT...H850-700 FGEN FIELDS INCREASING...PWAT ANOMOLIES REMAIN 1-3 STANDARD DEVIATIONS ABOVE NORMAL AND INCREASING LOW LEVEL SOUTHEAST JET ALL POINT TOWARD MODERATE TO HEAVY RAIN. PER CSTAR RESEARCH...THE SYNOPTIC PATTERN RESEMBLES THAT OF A HP NEUTRAL CUT OFF UPPER LOW WHICH IS HIGHLY SUSCEPTIBLE FOR FLOODING ACROSS OUR SERVICE AREA. WE WILL RETAIN THE FLOOD WATCH AS THE COMBINATION OF RUN OFF /NEARLY FROZEN GROUND DESPITE THE FIRST COUPLE OF INCHES LIKELY DEFROSTED AT THIS TIME/ AND POTENTIAL FROM ICE JAMS WILL BE ON THE INCREASE. SEE THE HYDROLOGY DISCUSSION BELOW FOR FURTHER DETAILS. && .SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY/... SUNDAY...THE SURFACE LOW OVER THE CENTRAL APPALACHIANS WILL BECOME NEARLY VERTICALLY STACKED OVER THE DELMARVA REGION SUNDAY MORNING. MID LEVEL DRY SLOT IS EXPECTED TO RACE NORTHWARD WHICH WILL LIKELY DIMINISH THE INTENSITY OF THE PRECIPITATION ACROSS THE REGION FROM SOUTH TO NORTH. POCKETS OF DRIZZLE/LIGHT RAIN AND SOME LIGHT WINTRY MIX ACROSS THE DACKS ARE EXPECTED. GLOBAL MODEL TRENDS ARE FAVORING A NORTHEAST TO SOUTHWEST ORIENTED BAND OF ENHANCED PRECIP TO DEVELOP SOMEWHERE OVER THE WESTERN DACKS...WESTERN MOHAWK VALLEY AND CATSKILLS THROUGH THE AFTERNOON AS THIS LOW SLOWLY MOVES OFF THE MID ATLANTIC COAST. ADDITIONAL PRECIPITATION WILL DEVELOP WITH PARTIAL THICKNESS SCHEME FROM THE GFS/ECMWF POINTING TOWARD A MIXTURE ACROSS THE HIGHER TERRAIN WEST OF THE HUDSON RIVER. SUNDAY NIGHT...CONSENSUS IS NOW FAVORING A RATHER IMPRESSIVE DEFORMATION AXIS OF PRECIP TO EVOLVE AND IMPACT THE CENTRAL PART OF OUR REGION FROM SOUTHERN VT...CAPITAL DISTRICT...EASTERN MOHAWK VALLEY AND CATSKILL REGION. EQUALLY AS CHALLENGING WILL BE THE THERMAL PROFILES AS CROSS SECTIONS SUGGEST THE BOUNDARY LAYER WILL COOL OFF TO ALLOW FOR THE PRECIP TO MIX WITH SLEET AND/OR FREEZING RAIN FOR MOST OF THE REGION. THIS EVENT PERIOD WILL NEED TO MONITORED VERY CLOSELY WITH ADDITIONAL WINTER WEATHER HEADLINES POSSIBLE. MONDAY...GLOBAL MODEL CONSENSUS IS NOW FAVORING THE DEFORMATION AXIS TO SLIDE EAST OF THE HUDSON IN THE MORNING AND CLEARING OUR WESTERN NEW ENGLAND COUNTIES BY MID AFTERNOON. THERMAL PROFILES POINT TOWARD A WINTRY MIXTURE / SNOW IN THE MORNING...THEN WITH WARMING BOUNDARY LAYER TEMPERATURES WE WILL GRADUALLY MIX WITH SOME RAIN BEFORE ENDING. AS NORTHERLY WINDS DOWN THE HUDSON INCREASE AND MIXING LAYER HEIGHTS CLIMBING TO AROUND H900...MID 20-MID 30 KTS OF WIND COULD MIX DOWN. AS FOR MOS GUIDANCE...WE WILL FAVOR CLOSER VALUES TO THE MAV/ECMWF. && .LONG TERM /MONDAY NIGHT THROUGH SATURDAY/... RIDGING ALOFT WILL BUILD INTO THE REGION FOR MONDAY NIGHT AND CONTINUE THROUGH THE MID WEEK PERIOD. THIS WILL ALLOW FOR TEMPERATURES TO RETURN TO NEAR SEASONABLE LEVELS...WITH MAINLY DRY CONDITIONS. MIN TEMPS ON MON NIGHT WILL BE IN THE 20S TO LOW 30S. MAX TEMPS ON TUESDAY WILL BE IN THE 50S /SOME UPPER 40S OVER THE HIGH TERRAIN/ WITH PLENTY OF SUNSHINE. THERE IS SOME UNCERTAINTY IN WHETHER A SYSTEM MOVING ACROSS THE UPPER GREAT LAKES CAN BRING SOME PRECIP TO THE REGION FOR TUESDAY NIGHT INTO WEDNESDAY. WHILE THE 12Z ECMWF SHOWS THE UPPER LEVEL RIDGE HOLDING IN AND KEEPING IT DRY...THE 12Z GFS IMPLIES THAT THE SYSTEM CAN BREAK DOWN THE RIDGE ENOUGH TO BRING A COLD FRONT THROUGH THE AREA...WITH SOME LIGHT RAIN AND SNOW SHOWERS /MAINLY FOR THE HIGH TERRAIN/. FOR NOW...WILL GO WITH A SLIGHT TO LOW CHC POPS FOR RAIN/SNOW SHOWERS...AND ONLY ALLOW FOR SNOW SHOWERS ACROSS THE HIGH TERRAIN AND AT NIGHT. MIN TEMPS ON TUESDAY NIGHT WILL BE IN THE 30S...AND MAX TEMPS ON WEDNESDAY WILL REACH THE MID 40S TO MID 50S. DRY WEATHER LOOKS TO RETURN FOR WED NIGHT INTO EARLY THURSDAY. HOWEVER...THIS LOOKS BRIEF...AS A SERIES OF SYSTEMS MOVING ACROSS THE OHIO VALLEY WILL APPROACH THE REGION FOR THE LATE WEEK PERIOD. SOME PRECIP MAY OCCUR ON THURSDAY NIGHT...AND THEN AGAIN LATER ON FRIDAY AND INTO SATURDAY. NORTHERN OR HIGH TERRAIN AREAS MAY SEE SOME SNOW AT THE ONSET OF THE PRECIP...OTHERWISE P-TYPE WILL BE RAIN...AS TEMPS LOOKS SEASONABLE FOR THIS TIME OF YEAR...ALONG WITH PLENTY OF CLOUDS. MIN TEMPS FOR THURS/FRI NIGHTS WILL BE IN THE 30S AND MAX TEMPS WILL BE IN THE 40S AND 50S FOR FRI AND SAT. && .AVIATION /19Z SATURDAY THROUGH THURSDAY/... A SLOW MOVING STORM SYSTEM OVER THE MID ATLANTIC REGION WILL SLOWLY MOVE UP THE NORTHEAST COAST OVER THE REMAINDER OF THE WEEKEND. FLYING CONDITIONS ARE CURRENTLY VFR FOR THE VALLEY SITES...WITH HIGH END MVFR AT KPSF DUE TO LINGERING LOW LEVEL MOISTURE KEEPS LOWER CIGS IN PLACE. RAIN IS CURRENTLY JUST ABOUT TO REACH KPOU...AND WILL CONTINUE TO SLOWLY ADVANCE NORTHWARD THROUGH THE AFTN AND EVENING HOURS. SHORTLY AFTER THE RAIN BEGINS...FLYING CONDITIONS FOR BOTH VSBYS/CIGS WILL LOWER TO MVFR. BY THE EVENING HOURS...THE RAIN WILL PICK UP IN INTENSITY...WHICH WILL LOWER CIGS/VSBYS TO IFR LEVELS FOR MUCH OF THE OVERNIGHT HOURS. THE RAIN WILL START TO DECREASE IN INTENSITY/COVERAGE TOWARDS DAYBREAK...ALLOWING VSBYS TO RETURN TO 4-6 SM...WITH JUST SOME AREAS OF LIGHT RAIN CONTINUING INTO THE DAY ON SUNDAY. CIGS MAY CONTINUE TO REMAIN IFR FOR A BIT INTO EARLY IN THE DAY ON SUNDAY /ESP AT KPSF/...BUT LOOK TO IMPROVE BACK TO MVFR SOMETIME DURING THE MORNING HOURS. WINDS WILL BECOME N-NE AND INCREASE TO AROUND 10-15 KTS FOR ALL SITES. THERE MAY BE A FEW HIGHER GUSTS OVERNIGHT AT KALB...AS AIR IS FUNNELED DOWN THE HUDSON VALLEY. N-NW WINDS AROUND 10 KTS LOOK TO CONTINUE RIGHT INTO THE DAY ON SUNDAY. OUTLOOK... SUN NIGHT: HIGH OPERATIONAL IMPACT. BREEZY. LIKELY RA...FZRA...SLEET. MON: MODERATE OPERATIONAL IMPACT. BREEZY. CHANCE OF RA...FZRA. MON NIGHT-TUE: NO OPERATIONAL IMPACT. NO SIG WX. TUE NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA. WED: NO OPERATIONAL IMPACT. NO SIG WX. && .FIRE WEATHER... NO FIRE WEATHER PROBLEMS ARE EXPECTED THE NEXT SEVERAL DAYS. WET WEATHER IS LIKELY FOR THE ENTIRE WEEKEND INTO MONDAY DUE TO THE COASTAL SYSTEM. SOME WINTRY PRECIPITATION WILL ALSO OCCUR NORTH OF THE CAPITAL REGION TONIGHT INTO SUNDAY. THE WINTRY PRECIPITATION COULD IMPACT MOST OF THE REGION SUNDAY NIGHT INTO MONDAY AS COLDER AIR FILTERS BACK INTO THE AREA. && .HYDROLOGY... A FLOOD WATCH REMAINS IN EFFECT OUTSIDE OF THE ADIRONDACK REGION STARTING AT 8 PM TONIGHT UNTIL MONDAY MORNING. THE POTENTIAL EXISTS FOR MINOR FLOODING FROM MODERATE TO HEAVY RAINFALL COMBINED WITH SNOWMELT. IN ADDITION...ICE BREAK UP AND ICE JAM FLOODING IS ALSO POSSIBLE. A SIGNIFICANT STORM SYSTEM WILL MOVE FROM THE MID ATLANTIC COAST TOWARDS LONG ISLAND TONIGHT INTO SUNDAY. THIS SYSTEM HAS THE POTENTIAL TO BRING MODERATE TO HEAVY AMOUNTS OF PRECIPITATION TO THE REGION...ESPECIALLY FOR AREAS FROM THE CAPITAL REGION SOUTH AND EAST...WITH A GENERAL CONSENSUS FROM THE GUIDANCE SHOWING ONE TO THREE INCHES OF RAINFALL ACROSS THE REGION. WHILE MUCH OF THIS WILL BE IN THE FORM OF RAINFALL...THERE IS THE POTENTIAL FOR THE PRECIP TO CHANGE TO A WINTRY MIX OR SNOWFALL BEFORE ENDING ACROSS THE REGION. CURRENT NERFC RIVER FORECASTS SHOW RISING LEVELS TO NEAR OR ABOVE FLOOD STAGE. THERE IS THE POTENTIAL FOR SIGNIFICANT RISES...ESPECIALLY ACROSS THE HOUSATONIC...HOOSIC...RONDOUT CREEK WILLIAMS RIVER AND METTAWEE BASINS. ALTHOUGH QPF AMOUNTS ARE NOW FORECAST TO RANGE BETWEEN 1 AND 2 WITH AMOUNTS UP TO 3 INCHES SOUTH OF THE CAPITAL REGION...THE CHALLENGE IS ICE BREAKING UP ON LARGER MAIN STEM RIVERS AS WELL...WHICH COULD POTENTIALLY CAUSE ICE JAMS IN SOME LOCATIONS. WITH THE BULK OF THE RAINFALL EXPECTED TO OCCUR TONIGHT INTO SUNDAY MORNING IN A RELATIVELY SHORT PERIOD OF TIME...SOME MINOR URBAN...LOW LYING...AND SMALL STREAM FLOODING COULD POTENTIALLY OCCUR AS WELL. THE MOST LIKELY AREAS TO SEE ISSUES WOULD BE FROM THE MOHAWK BASIN SOUTH AND EAST. DRIER WEATHER LOOKS TO RETURN FOR MONDAY NIGHT THROUGH WEDNESDAY OF NEXT WEEK...ALLOWING RIVERS AND STREAMS TO SLOWLY RECEDE. FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE. && .CLIMATE... HOW COLD HAS MARCH 2014 BEEN? THROUGH THE 28TH THE AVERAGE MONTHLY TEMPERATURE HAS BEEN 26.4 DEGREES WHICH IS 8.1 DEGREES BELOW NORMAL. ONLY 5 DAYS THIS MONTH AS THE AVERAGE DAILY TEMPERATURE BEEN ABOVE NORMAL. TOP 10 COLDEST MARCHES - ALBANY NY - RECORDS DATE BACK TO 1820. 1) 23.6 DEGREES 1885 2) 24.6 DEGREES 1863 3) 24.7 DEGREES 1875 4) 25.3 DEGREES 1843 5) 26.0 DEGREES 1888 6) 26.1 DEGREES 1916 7) 26.2 DEGREES 1869 8) 26.5 DEGREES 1960 9) 26.8 DEGREES 1940 10) 27.0 DEGREES 1836 && .ALY WATCHES/WARNINGS/ADVISORIES... CT...FLOOD WATCH FROM 8 PM EDT THIS EVENING THROUGH MONDAY MORNING FOR CTZ001-013. NY...FLOOD WATCH FROM 8 PM EDT THIS EVENING THROUGH MONDAY MORNING FOR NYZ038>041-043-047>054-058>061-063>066-082>084. WINTER WEATHER ADVISORY FROM 8 PM THIS EVENING TO NOON EDT SUNDAY FOR NYZ032-033-042. WINTER WEATHER ADVISORY FROM MIDNIGHT TONIGHT TO NOON EDT SUNDAY FOR NYZ043-083. MA...FLOOD WATCH FROM 8 PM EDT THIS EVENING THROUGH MONDAY MORNING FOR MAZ001-025. VT...FLOOD WATCH FROM 8 PM EDT THIS EVENING THROUGH MONDAY MORNING FOR VTZ013>015. && $$ SYNOPSIS...BGM NEAR TERM...BGM SHORT TERM...BGM LONG TERM...FRUGIS AVIATION...FRUGIS FIRE WEATHER...BGM/WASULA HYDROLOGY...BGM/WASULA CLIMATE...NWS STAFF FOR THE LATEST UPDATES...PLEASE VISIT OUR WEBPAGE AT WWW.WEATHER.GOV/ALBANY
AREA FORECAST DISCUSSION...UPDATED
NWS TAMPA BAY RUSKIN FL
940 PM EDT SUN MAR 30 2014 .UPDATE (REST OF TONIGHT AND MONDAY).. 01Z WATER VAPOR AND H4 RAP ANALYSIS SHOWS AN AMPLIFIED UPPER LEVEL PATTERN IN PLACE OVER THE EASTERN CONUS WITH A DEEP AND SHARP TROUGH/CLOSED LOW FEATURE EXITING OFF THE EASTERN SEABOARD. THIS TROUGH AXIS IS NOW OFF TO OUR EAST ALLOWING HEIGHTS TO REBOUND OVER THE EASTERN GULF OF MEXICO AND FLORIDA PENINSULA. AT THE SAME TIME AT THE SURFACE...HIGH PRESSURE IS QUICKLY BUILDING TO THE SOUTH AND EAST TOWARD THE REGION AND WILL BE IN PLACE OVER THE CENTRAL/NORTHERN PENINSULA FOR THE DAY ON MONDAY. THE DEVELOPING STACKED RIDGING AND VERY DRY COLUMN THROUGH THE MAJORITY OF THE COLUMN WILL ENSURE A CONTINUED DRY AND FAIR WEATHER PATTERN TO START OUT THE NEW WORK WEEK. THE EVENING KTBW SOUNDING PROFILE IS VERY VERY DRY BELOW 300MB MEASURING A PW OF ONLY AROUND 0.2". THIS IS A LOW VALUE FOR FLORIDA AT ANY TIME OF YEAR. IN FACT THIS VALUE IS GETTING DOWN TOWARD THE MINIMUM VALUE FOR PW EVER RECORDED FOR THIS DATE. GOES TO SHOW YOU...EVEN WHEN THE WEATHER SEEMS QUIET...SOME INTERESTING THINGS CAN STILL HAPPEN. THE ONLY MOISTURE IN THE COLUMN IS IN THE VERY UPPER LEVELS ASSOCIATED WITH THE SUBTROPICAL JET STRETCHED ACROSS THE GULF OF MEXICO. WE SAW PERIOD OF HIGH LEVEL CIRRUS PASSING OVERHEAD TODAY AND THIS EVENING ASSOCIATED WITH THE DYNAMICS ASSOCIATED WITH THIS FEATURE. THESE PERIOD OF FILTERED SUNSHINE WILL ALSO CONTINUE INTO MONDAY...WITH THE MOST CIRRUS LOOKING LIKE IT WILL BE TO THE SOUTH OF THE I-4 CORRIDOR. EITHER WAY...THE FORECAST LOOKS GOOD FOR ALL. TEMPERATURES WILL BE A LITTLE COOL OVERNIGHT...ESPECIALLY UP OVER THE NATURE COAST WHERE 40S...AND EVEN A FEW UPPER 30S ARE POSSIBLE BY SUNRISE. FURTHER SOUTH TOWARD TAMPA BAY AND SOUTHWARD...UPPER 40S TO LOWER 50S WILL BE MORE COMMON. TEMPERATURES WILL RECOVER QUICKLY DURING MONDAY WITH WIDESPREAD MIDDLE TO UPPER 70S FOR THE AFTERNOON AND WARMER SPOTS REACHING THE LOWER 80S TO THE SOUTH OF I-4. WILL NOT GO INTO MUCH DETAIL...BUT THE SYNOPTIC PATTERN SUGGEST A LONG STRETCH OF WARM AND DRY WEATHER LASTING THROUGH THE MAJORITY OF THE UPCOMING WEEK. ENJOY! && .AVIATION... 31/00-01/00Z; VFR PREVAIL. NW WINDS DIMINISH AND VEER TO NE THEN EASTERLY MON...ALTHOUGH A SEA BREEZE MAY BEGIN TO IMPACT SOME COASTAL TERMINALS TOWARD THE END OF THE PERIOD. && .MARINE... WIND SPEEDS AROUND EXERCISE CAUTION CRITERIA ARE EXPECTED OVER THE SOUTHERN GULF WATERS TONIGHT AND EXTENDING INTO THE CENTRAL OFFSHORE WATERS AS WELL...BUT THEN WIND SPEEDS WILL BEGIN TO RELAX FOR MONDAY AND WILL REMAIN BELOW HEADLINES THROUGH MID- WEEK. && .PRELIMINARY POINT TEMPS/POPS... TPA 51 77 58 82 / 0 0 0 0 FMY 54 82 58 86 / 0 0 0 0 GIF 51 79 56 83 / 0 0 0 0 SRQ 50 77 56 81 / 0 0 0 0 BKV 39 79 42 84 / 0 0 0 0 SPG 58 77 63 81 / 0 0 0 0 && .TBW WATCHES/WARNINGS/ADVISORIES... FL...NONE. GULF WATERS...NONE. && $$ UPDATE...MROCZKA AVIATION...RUDE
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
930 PM EDT SUN MAR 30 2014 .DISCUSSION... QUIET WX PATTERN OVERNIGHT AS A DEEP HI PRES RIDGE EXTENDING FROM THE LWR MS VALLEY TO THE WRN GOMEX DRIFTS SLOWLY EWD UNDER THE INFLUENCE OF A ZONAL H30-H20 FLOW. EVNG SOUNDINGS REFLECT THE POSITION OF THE RIDGE WELL: DEEP NWRLY FLOW PUSHING A VERY DRY/STABLE AIRMASS ACRS THE REGION...PWAT VALUES AOB 0.3" WITH AN 8-10C SUBSIDENCE INVERSION IN THE H95-H80 LYR. NO SIG WX OVERNIGHT AS THE LCL PGRAD WEAKENS...ALLOWING SFC WNDS TO DIMINISH TO ARND 5MPH. THE LIGHT WINDS MAY COMBINE WITH A SCT-BKN UPR LVL CLOUD DECK PUSHING ACRS THE AREA TO KEEP MIN TEMPS IN THE L/M50S...BUT ANY CHANGES TO THE AFTN PACKAGE WOULD BE LARGELY TRANSPARENT. NO UPDATES NECESSARY THIS EVENING. && .AVIATION... THRU 01/00Z...VFR ALL SITES...CIGS ABV FL120. SFC WNDSHFT FM N/NW TO E/NE AOB 10KTS BTWN 31/15Z-31/19Z. && .MARINE... LATEST RUC ANALYSIS INDICATES 15-20KT SFC/BNDRY LYR WINDS CONTINUE OVER THE OFFSHORE WATERS...BUT OBS FROM THE LCL DATA BUOY/C-MAN NETWORK SHOW ONLY SETTLEMENT POINT WITH SFC WINDS ARND 15KTS WITH GUSTS ARND 20KTS. THIS SUGGESTS CONDITIONS HAVE DROPPED BLO CAUTIONARY LVLS ACRS THE NEARSHORE WATERS BUT MAY STILL PERSIST ACRS THE OFFSHORE. SEAS RUNNING 2-3FT NEARSHORE AND 3-5FT OFFSHORE... DOMINANT PDS ARND 7SEC. SFC/BNDRY LYR WINDS WILL CONTINUE TO DIMINISH OVERNIGHT AS A SFC HI PRES RIDGE OVER THE DEEP SOUTH/CENTRAL GOMEX DRIFTS ACRS THE ERN GOMEX/FL PENINSULA. CAUTIONARY STATEMENT FOR OFFSHORE WATERS WILL CONTINUE OVERNIGHT...BUT WILL DISCONTINUE IT FOR ALL NEARSHORE WATERS. && .MLB WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. && $$ BRAGAW
AREA FORECAST DISCUSSION...UPDATED
NWS MIAMI FL
134 PM EDT SAT MAR 29 2014 .AVIATION... A LINE OF THUNDERSTORMS OVER CENTRAL FLORIDA WILL CONTINUE TO MOVE SOUTHEAST AND INTO SOUTH FLORIDA LATE THIS AFTERNOON INTO THIS EVENING. THE TIMING OF THE SHOWERS AND THUNDERSTORMS SHOULD AFFECT KPBI AND KAPF TAF SITES BETWEEN 23Z AND 01Z...KFXE AND KFLL BETWEEN 00Z AND 02Z...AND REST OF THE TAF SITES BETWEEN 01Z AND O3Z. SO HAVE DELAY THE VCTS UNTIL THE ABOVE TIMES FOR THE MENTION TAF SITES. THERE COULD ALSO BE SOME SHOWERS AHEAD AND BEHIND THE PASSAGE OF THE LINE OF STORMS. SO HAVE PUT IN VCSH 2 HOURS AHEAD AND BEHIND THE PASSAGE OF THE LINE OF STORMS. THE WINDS WILL BE SOUTHERLY AT 15 KNOTS WITH GUSTS UP TO 25 KNOTS OVER THE TAF SITES THIS AFTERNOON AHEAD OF THE LINE OF STORMS. THE WINDS WILL THEN SWING TO A MORE WESTERLY DIRECTION BEHIND THE PASSAGE OF THE STORMS WITH SPEEDS DOWN TO AROUND 5 TO 10 KNOTS. THE WINDS WILL THEN BECOME NORTHWEST AROUND 10 KNOTS ON SUNDAY WITH THE PASSAGE OF THE COLD FRONT. THE VIS WILL REMAIN IN THE VFR CONDITIONS OVER ALL OF THE TAF SITES WITH CEILINGS IN THE MVFR TO VFR CONDITIONS. THE CEILING AND VIS COULD FALL INTO THE IFR CONDITIONS WITH THE PASSAGE OF THE LINE OF STORMS...BUT WILL MAKE ADMIN TO THE TAF SITES ONCE THE LINE OF STORMS GET CLOSER TO THE TAF SITES. && .AVIATION...54/BNB .PREV DISCUSSION... /ISSUED 923 AM EDT SAT MAR 29 2014/ UPDATE... MADE SOME MINOR ADJUSTMENTS TO THE FORECAST BASED ON CURRENT TRENDS AND CURRENT OBSERVATIONS. HEAVY CLOUD FROM THUNDERSTORM DEBRIS FIELD CURRENTLY COVERS MOST OF SOUTH FLORIDA THIS MORNING. THE THUNDERSTORM COMPIEX IS LOCATED IN THE SOUTHEAST GULF OF MEXICO ABOUT 150 MILES WEST OF NAPLES AND WAS MOVING VERY LITTLE. THE MAIN TROUGH IS CURRENTLY DEEPENING OVER THE SOUTHERN GULF STATES WHICH IS GENERATING A LINE OF THUNDERSTORMS OVER THE NORTHEAST GULF OF MEXICO. MOST OF THIS ACTIVITY THROUGH THIS AFTERNOON WILL BE AFFECTING CENTRAL FLORIDA. THE 12Z MFL SOUNDING DOES SHOW SOME LOW LEVEL INSTABILITY BUT MID LEVEL LAPSE RATES REMAIN WEAK. THE KEY ASPECT FOR SOUTH FLORIDA WEATHER THROUGH THE REMAINDER OF THE DAY IS HOW MUCH CLEARING AND WARMING WILL TAKE PLACE THIS AFTERNOON. THERE ARE NO SIGNS OF CLOUDS THINNING AT THIS TIME AND THEREFORE LOWERED THE MAXIMUM TEMPERATURES ACROSS THE INTERIOR. IT APPEARS AT THIS TIME THAT THE MAIN THREAT WILL BE THIS EVENING AND OVERNIGHT AS THE MAIN BAND FROM THE NORTHEAST GULF ARRIVES IN SOUTH FLORIDA AND THIS IS WHAT THE HRRR IS SHOWING WITH NOT MUCH HAPPENING THROUGH AT LEAST 16Z AND SO FOLLOWED THIS GUIDANCE. && KOB PREV DISCUSSION... /ISSUED 653 AM EDT SAT MAR 29 2014/ AVIATION... A COLD FRONT OVER THE SOUTHEAST UNITED STATES WILL CONTINUE TO MOVE SOUTH TOWARDS SOUTH FLORIDA TODAY. THIS WILL ALLOW FOR THE WINDS OVER SOUTH FLORIDA TAF SITES TO SWING FROM A SOUTHEAST DIRECTION THIS MORNING TO A SOUTHWEST DIRECTION BY LATE THIS AFTERNOON INTO THIS EVENING. THE WIND SPEEDS WILL BE AROUND 10 KNOTS THIS MORNING INCREASING TO 10 TO 15 KNOTS BY THIS AFTERNOON...BEFORE DECREASING AGAIN TO AROUND 10 KNOTS THIS EVENING. THERE WILL BE A THREAT OF SHOWERS THIS MORNING OVER THE TAF SITES BEFORE A THUNDERSTORM THREAT THIS AFTERNOON MAINLY AFTER 18Z. THE VIS AND CEILINGS OVER SOUTH FLORIDA TAF SITES WILL REMAIN IN THE VFR CONDITIONS AT THIS TIME DUE TO THE UNKNOWN TIMING OF THE SHOWERS AND THUNDERSTORMS. BUT WHEN THEY DO DEVELOP AND PUSH THROUGH THE TAF SITES...THEY COULD FALL INTO THE IFR CONDITIONS. && PREV DISCUSSION... /ISSUED 403 AM EDT SAT MAR 29 2014/ DISCUSSION... MAIN FOCUS REMAINS OVER THE NEXT 24 TO 30 HOURS WITH SHOWER AND THUNDERSTORM CHANCES ASSOCIATED WITH THE PASSAGE OF A COLD FRONT. LATEST MICRON SATELLITE IMAGERY SHOWS A LINE OF THUNDERSTORMS ACROSS THE NORTHERN GULF OF MEXICO AHEAD OF A COLD FRONT. THESE STORMS ARE PUSHING TO THE EAST AND WILL AFFECT THE FLORIDA PANHANDLE THROUGH THE MORNING. AN AREA OF LOW PRESSURE WILL DEEPEN AS IT SLIDES TO THE NORTHEAST AND INTO THE APPALACHIANS. THIS WILL ALLOW THE COLD FRONT TO PUSH FURTHER SOUTH AND THROUGH THE AREA BY LATE TONIGHT AND INTO EARLY SUNDAY MORNING. SHOWERS AND THUNDERSTORMS WILL BEGIN TO PUSH INTO SOUTH FLORIDA LATER TODAY AS THE FRONT APPROACHES. BETTER DYNAMICS ARE STILL EXPECTED TO BE WELL NORTH OF THE AREA AND THE BEST FORCING ALONG THE FRONT LOOKS TO ARRIVE WELL AFTER DARK. HOWEVER...THE AIRMASS SHOULD STILL BE RATHER BUOYANT WITH MODEL SOUNDINGS DEPICTING SBCAPE VALUES AROUND 2000 J/KG. THEREFORE BELIEVE A FEW THUNDERSTORMS COULD PRODUCE GUSTY WINDS AND BRIEF HEAVY DOWNPOURS WITH THE GREATEST COVERAGE OF SHOWERS AND THUNDERSTORMS BEING OVERNIGHT. THE FRONT SHOULD EXIT THE AREA COMPLETELY BY MIDDAY SUNDAY ALLOWING A MUCH DRIER AIRMASS TO FILTER INTO THE AREA. STRONG PERSISTENT HIGH PRESSURE WILL THEN DOMINATE THE WEATHER ACROSS THE FLORIDA PENINSULA THROUGH VIRTUALLY ALL OF NEXT WEEK WITH NEAR NORMAL TEMPERATURES. AVIATION... A LOW PRESSURE SYSTEM OVER LOUISIANA WILL MOVE TO THE NORTHEAST THROUGH THE TAF PERIOD. THIS WILL INITIALLY JUST KEEP WINDS OUT OF THE SOUTHEAST WITH MID AND UPPER LEVEL CLOUDS. BY MID MORNING, CIGS WILL LOWER, BUT SHOULD STILL BE GENERALLY MVFR, IF NOT VFR. THERE WILL ALSO BE RAIN SHOWERS MOVING INTO SOUTH FLORIDA BY LATE MORNING. IT IS ALSO POSSIBLE THAT A FEW THUNDERSTORMS WILL DEVELOP FROM MID DAY ON, BUT THERE IS CURRENTLY TOO MUCH UNCERTAINTY TO PLACE THEM IN THE TAFS AT THIS TIME. WINDS WILL PICKUP JUST AFTER SUNRISE, OUT OF THE SOUTH-SOUTHEAST BETWEEN 10 AND 15 KTS. THEY WILL TURN MID DAY TO THE SOUTHWEST AT AROUND 15 KTS. A COLD FRONT WILL THEN MOVE ACROSS SOUTH FLORIDA SOMETIME IN THE OVERNIGHT HOURS. AHEAD OF THE FRONT, IN THE EVENING HOURS, THE WINDS WILL BE MORE WEST SOUTHWEST AT 5 TO 10 KTS. MARINE... NORTHEASTERLY SWELL WILL CONTINUE TO DIMINISH THROUGH THE DAY AS WINDS BECOME MORE SOUTHERLY. A COLD FRONT WILL CROSS THROUGH THE AREA WATERS OVERNIGHT TONIGHT AND INTO SUNDAY MORNING TURNING WINDS AROUND TO THE NORTH AND INCREASING TO AROUND 15 TO 20 MPH WITH A BRIEF CORRESPONDING INCREASE IN SEAS ON SUNDAY BEFORE DIMINISHING BY MONDAY AS WINDS DECREASE SLIGHTLY. && .PRELIMINARY POINT TEMPS/POPS... WEST PALM BEACH 83 69 79 57 / 50 50 10 0 FORT LAUDERDALE 82 72 81 65 / 40 50 10 0 MIAMI 83 72 81 63 / 40 50 10 0 NAPLES 82 70 79 55 / 40 50 10 0 && .MFL WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. GM...NONE. && $$ SHORT TERM...54/BNB LONG TERM....30/KOB AVIATION...54/BNB
AREA FORECAST DISCUSSION
NWS MIAMI FL
923 AM EDT SAT MAR 29 2014 .UPDATE... MADE SOME MINOR ADJUSTMENTS TO THE FORECAST BASED ON CURRENT TRENDS AND CURRENT OBSERVATIONS. HEAVY CLOUD FROM THUNDERSTORM DEBRIS FIELD CURRENTLY COVERS MOST OF SOUTH FLORIDA THIS MORNING. THE THUNDERSTORM COMPIEX IS LOCATED IN THE SOUTHEAST GULF OF MEXICO ABOUT 150 MILES WEST OF NAPLES AND WAS MOVING VERY LITTLE. THE MAIN TROUGH IS CURRENTLY DEEPENING OVER THE SOUTHERN GULF STATES WHICH IS GENERATING A LINE OF THUNDERSTORMS OVER THE NORTHEAST GULF OF MEXICO. MOST OF THIS ACTIVITY THROUGH THIS AFTERNOON WILL BE AFFECTING CENTRAL FLORIDA. THE 12Z MFL SOUNDING DOES SHOW SOME LOW LEVEL INSTABILITY BUT MID LEVEL LAPSE RATES REMAIN WEAK. THE KEY ASPECT FOR SOUTH FLORIDA WEATHER THROUGH THE REMAINDER OF THE DAY IS HOW MUCH CLEARING AND WARMING WILL TAKE PLACE THIS AFTERNOON. THERE ARE NO SIGNS OF CLOUDS THINNING AT THIS TIME AND THEREFORE LOWERED THE MAXIMUM TEMPERATURES ACROSS THE INTERIOR. IT APPEARS AT THIS TIME THAT THE MAIN THREAT WILL BE THIS EVENING AND OVERNIGHT AS THE MAIN BAND FROM THE NORTHEAST GULF ARRIVES IN SOUTH FLORIDA AND THIS IS WHAT THE HRRR IS SHOWING WITH NOT MUCH HAPPENING THROUGH AT LEAST 16Z AND SO FOLLOWED THIS GUIDANCE. KOB && .PREV DISCUSSION... /ISSUED 653 AM EDT SAT MAR 29 2014/ AVIATION... A COLD FRONT OVER THE SOUTHEAST UNITED STATES WILL CONTINUE TO MOVE SOUTH TOWARDS SOUTH FLORIDA TODAY. THIS WILL ALLOW FOR THE WINDS OVER SOUTH FLORIDA TAF SITES TO SWING FROM A SOUTHEAST DIRECTION THIS MORNING TO A SOUTHWEST DIRECTION BY LATE THIS AFTERNOON INTO THIS EVENING. THE WIND SPEEDS WILL BE AROUND 10 KNOTS THIS MORNING INCREASING TO 10 TO 15 KNOTS BY THIS AFTERNOON...BEFORE DECREASING AGAIN TO AROUND 10 KNOTS THIS EVENING. THERE WILL BE A THREAT OF SHOWERS THIS MORNING OVER THE TAF SITES BEFORE A THUNDERSTORM THREAT THIS AFTERNOON MAINLY AFTER 18Z. THE VIS AND CEILINGS OVER SOUTH FLORIDA TAF SITES WILL REMAIN IN THE VFR CONDITIONS AT THIS TIME DUE TO THE UNKNOWN TIMING OF THE SHOWERS AND THUNDERSTORMS. BUT WHEN THEY DO DEVELOP AND PUSH THROUGH THE TAF SITES...THEY COULD FALL INTO THE IFR CONDITIONS. PREV DISCUSSION... /ISSUED 403 AM EDT SAT MAR 29 2014/ DISCUSSION... MAIN FOCUS REMAINS OVER THE NEXT 24 TO 30 HOURS WITH SHOWER AND THUNDERSTORM CHANCES ASSOCIATED WITH THE PASSAGE OF A COLD FRONT. LATEST MICRON SATELLITE IMAGERY SHOWS A LINE OF THUNDERSTORMS ACROSS THE NORTHERN GULF OF MEXICO AHEAD OF A COLD FRONT. THESE STORMS ARE PUSHING TO THE EAST AND WILL AFFECT THE FLORIDA PANHANDLE THROUGH THE MORNING. AN AREA OF LOW PRESSURE WILL DEEPEN AS IT SLIDES TO THE NORTHEAST AND INTO THE APPALACHIANS. THIS WILL ALLOW THE COLD FRONT TO PUSH FURTHER SOUTH AND THROUGH THE AREA BY LATE TONIGHT AND INTO EARLY SUNDAY MORNING. SHOWERS AND THUNDERSTORMS WILL BEGIN TO PUSH INTO SOUTH FLORIDA LATER TODAY AS THE FRONT APPROACHES. BETTER DYNAMICS ARE STILL EXPECTED TO BE WELL NORTH OF THE AREA AND THE BEST FORCING ALONG THE FRONT LOOKS TO ARRIVE WELL AFTER DARK. HOWEVER...THE AIRMASS SHOULD STILL BE RATHER BUOYANT WITH MODEL SOUNDINGS DEPICTING SBCAPE VALUES AROUND 2000 J/KG. THEREFORE BELIEVE A FEW THUNDERSTORMS COULD PRODUCE GUSTY WINDS AND BRIEF HEAVY DOWNPOURS WITH THE GREATEST COVERAGE OF SHOWERS AND THUNDERSTORMS BEING OVERNIGHT. THE FRONT SHOULD EXIT THE AREA COMPLETELY BY MIDDAY SUNDAY ALLOWING A MUCH DRIER AIRMASS TO FILTER INTO THE AREA. STRONG PERSISTENT HIGH PRESSURE WILL THEN DOMINATE THE WEATHER ACROSS THE FLORIDA PENINSULA THROUGH VIRTUALLY ALL OF NEXT WEEK WITH NEAR NORMAL TEMPERATURES. AVIATION... A LOW PRESSURE SYSTEM OVER LOUISIANA WILL MOVE TO THE NORTHEAST THROUGH THE TAF PERIOD. THIS WILL INITIALLY JUST KEEP WINDS OUT OF THE SOUTHEAST WITH MID AND UPPER LEVEL CLOUDS. BY MID MORNING, CIGS WILL LOWER, BUT SHOULD STILL BE GENERALLY MVFR, IF NOT VFR. THERE WILL ALSO BE RAIN SHOWERS MOVING INTO SOUTH FLORIDA BY LATE MORNING. IT IS ALSO POSSIBLE THAT A FEW THUNDERSTORMS WILL DEVELOP FROM MID DAY ON, BUT THERE IS CURRENTLY TOO MUCH UNCERTAINTY TO PLACE THEM IN THE TAFS AT THIS TIME. WINDS WILL PICKUP JUST AFTER SUNRISE, OUT OF THE SOUTH-SOUTHEAST BETWEEN 10 AND 15 KTS. THEY WILL TURN MID DAY TO THE SOUTHWEST AT AROUND 15 KTS. A COLD FRONT WILL THEN MOVE ACROSS SOUTH FLORIDA SOMETIME IN THE OVERNIGHT HOURS. AHEAD OF THE FRONT, IN THE EVENING HOURS, THE WINDS WILL BE MORE WEST SOUTHWEST AT 5 TO 10 KTS. MARINE... NORTHEASTERLY SWELL WILL CONTINUE TO DIMINISH THROUGH THE DAY AS WINDS BECOME MORE SOUTHERLY. A COLD FRONT WILL CROSS THROUGH THE AREA WATERS OVERNIGHT TONIGHT AND INTO SUNDAY MORNING TURNING WINDS AROUND TO THE NORTH AND INCREASING TO AROUND 15 TO 20 MPH WITH A BRIEF CORRESPONDING INCREASE IN SEAS ON SUNDAY BEFORE DIMINISHING BY MONDAY AS WINDS DECREASE SLIGHTLY. && .MFL WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. GM...NONE. && $$
AREA FORECAST DISCUSSION
NWS TALLAHASSEE FL
605 AM EDT Sat Mar 29 2014 .Near Term [Through Today]... The 09 UTC regional surface analysis continued to be largely dominated by mesoscale features. The wake low analyzed in South GA earlier tonight has weakened, and a new meso high (induced by a cold pool from the MCS to our west) has developed in the western FL Panhandle. The strong, well-organized MCS at the beginning of our shift has weakened and now appears rather sloppy on satellite & radar imagery. The storms that moved into our western zones have been mostly elevated, and this will likely continue until later this morning when (if) there is some heating. The HRRR has been handling the simulated reflectivity well so far and we have followed it closely for this forecast update. Most of our local WRFs appears to be too slow, so we have sped up the timing of the rain from our earlier forecast. This means that most of the rain will end from west to east this afternoon. Because of this faster solution, the severe threat may be diminishing a bit, as the most of the storms may be east of our forecast area by the time the boundary layer destabilizes significantly. Still, we can`t rule out an isolated severe storm given the strong winds and relatively steep lapse rates aloft. Damaging wind gusts and hail are the main threats, but we can`t completely rule out an brief tornado. .Short Term [Tonight Through Monday]... Deep layer ridging and a very dry airmass will build into the region in the wake of the exiting upper trough and surface cold front. Max temps will be near to above seasonal levels while min temps will be cooler, especially Sunday night with nearly ideal radiational cooling conditions setting up. Max temps will be in the lower to mid 70s Sunday and upper 70s to near 80 on Monday. Lows will be in the in the lower to mid 40s tonight and around 40 Sunday night. .Long Term [Monday Night Through Saturday]... Upper level ridging will stay in place over the southeastern CONUS through Wednesday. Wednesday night, another shortwave trough over the four corners region will amplify the upper level pattern, developing a surface low over the southern Plains and an associated cold front. As this system pushes eastward Thursday and Friday, chances for showers and thunderstorms increase from west to east across our forecast area. && .Aviation... [Through 12Z Sunday] Numerous SHRA and TSRA will be moving east through the region today, mainly this morning. Gusty winds and poor brief period of poor visibility are expected at all terminals. The rain will end from west to east later this morning. Skies will be clearing later this afternoon as the winds shift and become NW to N. && .Marine... Winds and seas will increase from from west to east to advisory levels from this evening to Sunday morning in the wake of an exiting strong cold front. Conditions will improve by Sunday afternoon with light winds and low seas for Monday through the middle of next week. && .Fire Weather... Wet conditions are expected today. RH values may fall to locally critical levels Sunday afternoon. However, at this time we don`t think that ERC/fuel moisture values and/or wind speeds will be sufficient for Red Flag warnings. && .Hydrology... Widespread rainfall amounts of 2 to 4 inches were received over Southeast Alabama and the Florida Panhandle...with 1 to 2 inches elsewhere. An additional 0.50 TO 1 inch rainfall amounts are expected across these areas today as a cold front pushes through. Many area rivers remain in action stage and could possibly reach minor flood stage. However, the latest forecast from the RFC keep everything below flood stage. For the latest river stages and forecasts, please visit: water.weather.gov/ahps2/index.php?wfo=tae && .Preliminary Point Temps/PoPs... Tallahassee 80 46 74 38 79 / 80 10 0 0 0 Panama City 75 47 72 47 75 / 80 0 0 0 0 Dothan 76 43 71 41 78 / 80 0 0 0 0 Albany 76 43 72 40 79 / 80 0 0 0 0 Valdosta 77 44 72 40 78 / 80 10 0 0 0 Cross City 79 47 74 40 78 / 70 10 0 0 0 Apalachicola 74 48 70 44 73 / 70 0 0 0 0 && .TAE Watches/Warnings/Advisories... FL...High Rip Current Risk through this evening for Coastal Bay- Coastal Franklin-Coastal Gulf-South Walton. GA...None. AL...None. GM...Small Craft Advisory from 11 PM this evening to 10 AM EDT Sunday for Apalachee Bay-Coastal waters from Suwannee River to Keaton Beach FL out 20 NM. Small Craft Advisory from 6 PM this evening to 10 AM EDT Sunday for Coastal waters From Ochlockonee River to Apalachicola FL out to 20 NM-Coastal waters from Apalachicola to Destin FL out 20 NM-Waters from Suwannee River to Apalachicola FL from 20 to 60 NM-Waters from Apalachicola to Destin FL from 20 to 60 NM. && $$ NEAR TERM...FOURNIER SHORT TERM...BARRY LONG TERM...MOORE AVIATION...FOURNIER MARINE...BARRY FIRE WEATHER...FOURNIER HYDROLOGY...BARRY/BOLDEN
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
646 PM EDT SAT MAR 29 2014 .SYNOPSIS... A COLD FRONT WILL MOVE THROUGH THE AREA TONIGHT. DRY HIGH PRESSURE WILL PREVAIL THROUGH THURSDAY. A COLD FRONT WILL MOVE THROUGH NEXT FRIDAY OR SATURDAY...FOLLOWED BY HIGH PRESSURE. && .NEAR TERM /UNTIL 6 AM SUNDAY MORNING/... A WELL PRONOUNCED PRE-FRONTAL TROUGH IS MOVING STEADILY EAST- NORTHEAST THROUGH THE FORECAST AREA LATE THIS AFTERNOON AND WAS ROUGHLY ALIGNED FROM KOGB-KNBC-FPGK1 AT 29/21Z. THE BEST CHANCES FOR SHOWERS/TSTMS WILL BE FOUND AHEAD OF THIS FEATURE...BUT WITH RAP SOUNDINGS SHOWING THE ATMOSPHERE BECOMING INCREASINGLY CAPPED AS DRY SLOT ROTATES THROUGH AHEAD OF THE UPPER TROUGH...THE PROSPECTS FOR DEEP/MOIST CONVECTION IS QUICKLY ENDING. HAVE UPDATED POPS TO REDUCE THEM DOWN TO SLIGHT CHANCE ALONG AND AHEAD OF THE TROUGH THROUGH SUNSET. SOME LIGHT SHOWER ACTIVITY MOVING THROUGH CENTRAL GEORGIA ASSOCIATED WITH THE COLD FRONT ITSELF IS EXPECTED TO DISSIPATE AS IT APPROACHES THE WESTERN PORTIONS OF THE FORECAST AREA PER LATEST RUNS OF THE RAP AND H3R. ALTHOUGH A SPRINKLE OR TWO COULD OCCUR...THE PROSPECTS FOR MEASURABLE PRECIPITATION THERE HAS LIKELY ENDED. THE RISK FOR SEVERE TSTMS HAS ALSO ENDED AND THE HAZARDOUS WEATHER OUTLOOK HAS BEEN UPDATED TO REFLECT THIS. SEA FOG CONTINUES TO AFFECT THE SOUTH CAROLINA NEARSHORE WATERS LATE THIS AFTERNOON. SOME OF THIS WILL IMPACT AREAS EAST OF HIGHWAY 17 IN SOUTH CAROLINA FOR ANOTHER FEW HOURS BEFORE WINDS VEER WESTERLY WITH THE PASSAGE OF THE PRE- FRONTAL TROUGH. LAKE WINDS...WINDS WILL TURN MORE WESTERLY AND INCREASE SHARPLY OVER LAKE MOULTRIE LATE TONIGHT. GUSTS TO 30 KT WILL BE POSSIBLE ALONG AND IMMEDIATELY BEHIND THE FRONT AND WILL CONTINUE GUSTING INTO THE 25-30 KT RANGE THROUGH SUNRISE. A LAKE WIND ADVISORY IS IN PLACE AND WILL BE MAINTAINED AS SUCH. && .SHORT TERM /6 AM SUNDAY MORNING THROUGH TUESDAY/... DRY HIGH PRESSURE WILL SURGE INTO THE AREA SUNDAY AS THE UPPER LEVEL RIDGE TAKES HOLD. 29/12Z GUIDANCE DEPICTS SOME WRAP-AROUND MOISTURE IN THE 4-8 KFT AGL LAYER SWINGING THROUGH NORTHERN COUNTIES... PERHAPS SUPPORTING SOME CLOUDS THERE. ELSEWHERE...FULL SUNSHINE SHOULD PREVAIL. ALTHOUGH WEAK COLD ADVECTION IS FORECAST...STRONG DOWNSLOPE FLOW AS STRONG AS 35-45 KT IN THE 925-850 MB LAYER WILL PRODUCE CONSIDERABLE ADIABATIC HEATING. HIGH TEMPERATURES WILL CLIMB INTO THE LOWER 70S IN SOUTHEAST GA WITH UPPER 60S ELSEWHERE. MODEL SOUNDINGS INDICATE A 6-7 KFT MIXED LAYER DURING THE DAYTIME HOURS...WHICH WILL SUPPORT SURFACE GUSTS 30-35 MPH. WINDS WILL DIMINISH SUBSTANTIALLY AFTER SUNSET SUNDAY EVENING. THE SURFACE HIGH WILL GRADUALLY BUILD EAST AND NW WINDS WILL CONTINUE TO DIMINISH SUNDAY NIGHT...ALTHOUGH 29/12Z GUIDANCE SUGGESTS THAT NW WINDS WILL PERSIST ESPECIALLY ACROSS SC COUNTIES WELL INTO THE NIGHT. NEVERTHELESS...UNDER CLEAR SKIES TEMPERATURES BY DAYBREAK MONDAY COULD DROP INTO THE UPPER 30S FAR INLAND WITH LOWER TO MID 40S ELSEWHERE. MONDAY THROUGH TUESDAY...A STRONG DEEP LAYERED RIDGE WILL BUILD OVER THE SOUTHEAST UNITED STATES...PROVIDING INCREASING LOW-LEVEL THICKNESSES AND AMPLE SUNSHINE. HIGH TEMPS WILL WARM INTO THE MID/UPPER 70S MONDAY AND INTO THE LOWER 80S AT MANY LOCATIONS TUESDAY. UNDER CLEAR SKIES/WITH LIGHT WINDS...RADIATIONAL COOLING WILL SUPPORT LOWS IN THE MID TO UPPER 40S AT MOST LOCATIONS AWAY FROM THE BEACHES. A FEW OF THE COOLER INLAND LOCATIONS COULD FALL TO AROUND 40. && .LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... DEEP LAYERED RIDGING WILL PERSIST TUESDAY NIGHT THROUGH THURSDAY NIGHT WITH ABOVE NORMAL TEMPERATURES AND DRY CONDITIONS. A PROGRESSIVE UPPER LOW WILL MOVE THROUGH THE OHIO VALLEY LATE IN THE WEEK...PUSHING A COLD FRONT THROUGH THE AREA FRIDAY OR FRIDAY NIGHT. THIS MAY BRING A FEW SHOWERS AND THUNDERSTORMS TO THE AREA BEFORE DRY HIGH PRESSURE REBUILDS NEXT WEEKEND. && .AVIATION /00Z SUNDAY THROUGH THURSDAY/... VFR. THE RISK FOR SHOWERS/TSTMS IMPACTING THE TERMINALS IS DIMINISHING. WINDS WILL TURN MORE WESTERLY AND BECOME GUSTY AS SKIES BEGIN TO CLEAR OUT WITH THE ARRIVAL OF DRIER AIR. LOW END 20-23 KT GUSTS WILL BE FREQUENT OVERNIGHT. THIS WILL INCREASE INTO THE 27-30 KT RANGE FROM MID SUNDAY MORNING ONWARD AS WINDS BECOME MORE NORTHWESTERLY. EXTENDED AVIATION OUTLOOK...NORTHWEST WINDS WILL GUST 25-30 KNOTS AT BOTH TERMINALS SUNDAY. && .MARINE... CANCELLED THE MARINE DENSE FOG ADVISORY FOR THE BEAUFORT COUNTY WATERS. CONDITIONS HAVE IMPROVED THERE AS WINDS TURN SOUTHWEST AHEAD OF AN APPROACHING COLD FRONT. THIS AFTERNOON AND TONIGHT...THE BIGGEST IMMEDIATE CONCERN FOR THE LOCAL WATERS IS THE ONGOING DENSE FOG EVENT ACROSS THE NEARSHORE ZONES. COASTAL WEB CAMS SHOW THAT VISIBILITIES ARE STILL QUITE POOR SO THE DENSE FOG ADVISORY CONTINUES INTO THE EVENING. THE FOG WILL DISSIPATE ONCE WINDS BEGIN TO TURN MORE WESTERLY...WHICH WILL CERTAINLY OCCUR WITH THE ARRIVAL OF THE COLD FRONT. THEN FOCUS TURNS TO THE WESTERLY SURGE THAT WILL TAKE PLACE BEHIND THE STRONG COLD FRONT. BASED ON INCOMING MODEL DATA...I HAVE OPTED TO INCREASE EXPECTED WINDS TO BE 25-30 KT ACROSS THE NEARSHORE WATERS LATE TONIGHT. FURTHERMORE...THE SMALL CRAFT ADVISORY HAS BEEN UPGRADED TO A GALE WARNING FOR THE OUTER GEORGIA WATERS WITH EXPECTED WINDS OF 30-35 KT. THE HARBOR WILL SEE SUSTAINED WINDS IN THE 20-25 KT RANGE WITH GUSTS TO 30 KT AS WELL. WITH THE ARRIVAL OF THE FRONT AND IMMEDIATELY BEHIND IT...THERE MAY BE AN ISOLATED GUST TO GALE FORCE IN THE HARBOR AND THE NEARSHORE WATERS...BUT THIS IS NOT EXPECTED TO BE FOR A DURATION LONG ENOUGH TO WARRANT A GALE WARNING. SEAS WILL REMAIN ELEVATED THROUGH TONIGHT WITH THE INCREASE IN LOW LEVEL FLOW...AND BECOME INCREASINGLY WIND DRIVEN IN NATURE. SUNDAY INTO SUNDAY NIGHT...ELEVATED WINDS/SEAS WILL PERSIST. GALE FORCE GUSTS WILL CONTINUE ACROSS AMZ374...FOLLOWED BY SMALL CRAFT ADVISORY WINDS/SEAS SUNDAY NIGHT...AND SMALL CRAFT ADVISORY CONDITIONS WILL CONTINUE ELSEWHERE SUNDAY THROUGH SUNDAY EVENING... AND ELEVATED WINDS/SEAS WILL PERSIST INTO EARLY MONDAY. AS HIGH PRESSURE BUILDS OVER THE WATERS...A WEAKENING PRESSURE PATTERN WILL TRANSLATE TO MUCH MORE TRANQUIL CONDITIONS MONDAY AFTERNOON THROUGH MIDWEEK. A SEA BREEZE CIRCULATION WILL DEVELOP EACH AFTERNOON. AHEAD OF THE NEXT APPROACHING COLD FRONT...INCREASING SOUTHERLY WINDS AND BUILDING SEAS ARE EXPECTED AND THE PROBABILITY FOR MARINE FLAGS WILL INCREASE THURSDAY/FRIDAY. && .FIRE WEATHER... SUNDAY...NORTHWEST/DOWNSLOPE WINDS WILL GUST TO 30-35 MPH AS MINIMUM RELATIVE HUMIDITY AVERAGES 20 TO 30 PERCENT. PER COLLABORATION WITH FIRE WEATHER PARTNERS...NO FIRE WEATHER WATCHES/RED FLAG WARNINGS ARE NEEDED DUE TO ELEVATED FUEL MOISTURE PRODUCED BY RECENT RAINFALL. && .CHS WATCHES/WARNINGS/ADVISORIES... GA...NONE. SC...LAKE WIND ADVISORY UNTIL MIDNIGHT EDT SUNDAY NIGHT FOR SCZ045. MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT SUNDAY FOR AMZ352-354. DENSE FOG ADVISORY UNTIL 10 PM EDT THIS EVENING FOR AMZ350. SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT SUNDAY NIGHT FOR AMZ330-350. GALE WARNING UNTIL 6 PM EDT SUNDAY FOR AMZ374. && $$ ST
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
543 PM EDT SAT MAR 29 2014 .SYNOPSIS... A COLD FRONT WILL MOVE THROUGH THE AREA TONIGHT. DRY HIGH PRESSURE WILL PREVAIL THROUGH THURSDAY. A COLD FRONT WILL MOVE THROUGH NEXT FRIDAY OR SATURDAY...FOLLOWED BY HIGH PRESSURE. && .NEAR TERM /UNTIL 6 AM SUNDAY MORNING/... A WELL PRONOUNCED PRE-FRONTAL TROUGH IS MOVING STEADILY EAST- NORTHEAST THROUGH THE FORECAST AREA LATE THIS AFTERNOON AND WAS ROUGHLY ALIGNED FROM KOGB-KNBC-FPGK1 AT 29/21Z. THE BEST CHANCES FOR SHOWERS/TSTMS WILL BE FOUND AHEAD OF THIS FEATURE...BUT WITH RAP SOUNDINGS SHOWING THE ATMOSPHERE BECOMING INCREASINGLY CAPPED AS DRY SLOT ROTATES THROUGH AHEAD OF THE UPPER TROUGH...THE PROSPECTS FOR DEEP/MOIST CONVECTION IS QUICKLY ENDING. HAVE UPDATED POPS TO REDUCE THEM DOWN TO SLIGHT CHANCE ALONG AND AHEAD OF THE TROUGH THROUGH SUNSET. SOME LIGHT SHOWER ACTIVITY MOVING THROUGH CENTRAL GEORGIA ASSOCIATED WITH THE COLD FRONT ITSELF IS EXPECTED TO DISSIPATE AS IT APPROACHES THE WESTERN PORTIONS OF THE FORECAST AREA PER LATEST RUNS OF THE RAP AND H3R. ALTHOUGH A SPRINKLE OR TWO COULD OCCUR...THE PROSPECTS FOR MEASURABLE PRECIPITATION THERE HAS LIKELY ENDED. THE RISK FOR SEVERE TSTMS HAS ALSO ENDED AND THE HAZARDOUS WEATHER OUTLOOK HAS BEEN UPDATED TO REFLECT THIS. SEA FOG CONTINUES TO AFFECT THE SOUTH CAROLINA NEARSHORE WATERS LATE THIS AFTERNOON. SOME OF THIS WILL IMPACT AREAS EAST OF HIGHWAY 17 IN SOUTH CAROLINA FOR ANOTHER FEW HOURS BEFORE WINDS VEER WESTERLY WITH THE PASSAGE OF THE PRE- FRONTAL TROUGH. LAKE WINDS...WINDS WILL TURN MORE WESTERLY AND INCREASE SHARPLY OVER LAKE MOULTRIE LATE TONIGHT. GUSTS TO 30 KT WILL BE POSSIBLE ALONG AND IMMEDIATELY BEHIND THE FRONT AND WILL CONTINUE GUSTING INTO THE 25-30 KT RANGE THROUGH SUNRISE. A LAKE WIND ADVISORY IS IN PLACE AND WILL BE MAINTAINED AS SUCH. && .SHORT TERM /6 AM SUNDAY MORNING THROUGH TUESDAY/... DRY HIGH PRESSURE WILL SURGE INTO THE AREA SUNDAY AS THE UPPER LEVEL RIDGE TAKES HOLD. 29/12Z GUIDANCE DEPICTS SOME WRAP-AROUND MOISTURE IN THE 4-8 KFT AGL LAYER SWINGING THROUGH NORTHERN COUNTIES... PERHAPS SUPPORTING SOME CLOUDS THERE. ELSEWHERE...FULL SUNSHINE SHOULD PREVAIL. ALTHOUGH WEAK COLD ADVECTION IS FORECAST...STRONG DOWNSLOPE FLOW AS STRONG AS 35-45 KT IN THE 925-850 MB LAYER WILL PRODUCE CONSIDERABLE ADIABATIC HEATING. HIGH TEMPERATURES WILL CLIMB INTO THE LOWER 70S IN SOUTHEAST GA WITH UPPER 60S ELSEWHERE. MODEL SOUNDINGS INDICATE A 6-7 KFT MIXED LAYER DURING THE DAYTIME HOURS...WHICH WILL SUPPORT SURFACE GUSTS 30-35 MPH. WINDS WILL DIMINISH SUBSTANTIALLY AFTER SUNSET SUNDAY EVENING. THE SURFACE HIGH WILL GRADUALLY BUILD EAST AND NW WINDS WILL CONTINUE TO DIMINISH SUNDAY NIGHT...ALTHOUGH 29/12Z GUIDANCE SUGGESTS THAT NW WINDS WILL PERSIST ESPECIALLY ACROSS SC COUNTIES WELL INTO THE NIGHT. NEVERTHELESS...UNDER CLEAR SKIES TEMPERATURES BY DAYBREAK MONDAY COULD DROP INTO THE UPPER 30S FAR INLAND WITH LOWER TO MID 40S ELSEWHERE. MONDAY THROUGH TUESDAY...A STRONG DEEP LAYERED RIDGE WILL BUILD OVER THE SOUTHEAST UNITED STATES...PROVIDING INCREASING LOW-LEVEL THICKNESSES AND AMPLE SUNSHINE. HIGH TEMPS WILL WARM INTO THE MID/UPPER 70S MONDAY AND INTO THE LOWER 80S AT MANY LOCATIONS TUESDAY. UNDER CLEAR SKIES/WITH LIGHT WINDS...RADIATIONAL COOLING WILL SUPPORT LOWS IN THE MID TO UPPER 40S AT MOST LOCATIONS AWAY FROM THE BEACHES. A FEW OF THE COOLER INLAND LOCATIONS COULD FALL TO AROUND 40. && .LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... DEEP LAYERED RIDGING WILL PERSIST TUESDAY NIGHT THROUGH THURSDAY NIGHT WITH ABOVE NORMAL TEMPERATURES AND DRY CONDITIONS. A PROGRESSIVE UPPER LOW WILL MOVE THROUGH THE OHIO VALLEY LATE IN THE WEEK...PUSHING A COLD FRONT THROUGH THE AREA FRIDAY OR FRIDAY NIGHT. THIS MAY BRING A FEW SHOWERS AND THUNDERSTORMS TO THE AREA BEFORE DRY HIGH PRESSURE REBUILDS NEXT WEEKEND. && .AVIATION /22Z SATURDAY THROUGH THURSDAY/... VFR. THE RISK FOR SHOWERS/TSTMS IMPACTING THE TERMINALS IS DIMINISHING. WINDS WILL TURN MORE WESTERLY AND BECOME GUSTY AS SKIES BEGIN TO CLEAR OUT WITH THE ARRIVAL OF DRIER AIR. LOW END 20-23 KT GUSTS WILL BE FREQUENT OVERNIGHT. THIS WILL INCREASE INTO THE 27-30 KT RANGE FROM MID SUNDAY MORNING ONWARD AS WINDS BECOME MORE NORTHWESTERLY. EXTENDED AVIATION OUTLOOK...NORTHWEST WINDS WILL GUST 25-30 KNOTS AT BOTH TERMINALS SUNDAY. && .MARINE... CANCELLED THE MARINE DENSE FOG ADVISORY FOR THE GEORGIA NEARSHORE WATERS. CONDITIONS HAVE IMPROVED THERE AS WINDS TURN SOUTHWEST AHEAD OF AN APPROACHING COLD FRONT. THIS AFTERNOON AND TONIGHT...THE BIGGEST IMMEDIATE CONCERN FOR THE LOCAL WATERS IS THE ONGOING DENSE FOG EVENT ACROSS THE NEARSHORE ZONES. COASTAL WEB CAMS SHOW THAT VISIBILITIES ARE STILL QUITE POOR SO THE DENSE FOG ADVISORY CONTINUES INTO THE EVENING. THE FOG WILL DISSIPATE ONCE WINDS BEGIN TO TURN MORE WESTERLY...WHICH WILL CERTAINLY OCCUR WITH THE ARRIVAL OF THE COLD FRONT. THEN FOCUS TURNS TO THE WESTERLY SURGE THAT WILL TAKE PLACE BEHIND THE STRONG COLD FRONT. BASED ON INCOMING MODEL DATA...I HAVE OPTED TO INCREASE EXPECTED WINDS TO BE 25-30 KT ACROSS THE NEARSHORE WATERS LATE TONIGHT. FURTHERMORE...THE SMALL CRAFT ADVISORY HAS BEEN UPGRADED TO A GALE WARNING FOR THE OUTER GEORGIA WATERS WITH EXPECTED WINDS OF 30-35 KT. THE HARBOR WILL SEE SUSTAINED WINDS IN THE 20-25 KT RANGE WITH GUSTS TO 30 KT AS WELL. WITH THE ARRIVAL OF THE FRONT AND IMMEDIATELY BEHIND IT...THERE MAY BE AN ISOLATED GUST TO GALE FORCE IN THE HARBOR AND THE NEARSHORE WATERS...BUT THIS IS NOT EXPECTED TO BE FOR A DURATION LONG ENOUGH TO WARRANT A GALE WARNING. SEAS WILL REMAIN ELEVATED THROUGH TONIGHT WITH THE INCREASE IN LOW LEVEL FLOW...AND BECOME INCREASINGLY WIND DRIVEN IN NATURE. SUNDAY INTO SUNDAY NIGHT...ELEVATED WINDS/SEAS WILL PERSIST. GALE FORCE GUSTS WILL CONTINUE ACROSS AMZ374...FOLLOWED BY SMALL CRAFT ADVISORY WINDS/SEAS SUNDAY NIGHT...AND SMALL CRAFT ADVISORY CONDITIONS WILL CONTINUE ELSEWHERE SUNDAY THROUGH SUNDAY EVENING... AND ELEVATED WINDS/SEAS WILL PERSIST INTO EARLY MONDAY. AS HIGH PRESSURE BUILDS OVER THE WATERS...A WEAKENING PRESSURE PATTERN WILL TRANSLATE TO MUCH MORE TRANQUIL CONDITIONS MONDAY AFTERNOON THROUGH MIDWEEK. A SEA BREEZE CIRCULATION WILL DEVELOP EACH AFTERNOON. AHEAD OF THE NEXT APPROACHING COLD FRONT...INCREASING SOUTHERLY WINDS AND BUILDING SEAS ARE EXPECTED AND THE PROBABILITY FOR MARINE FLAGS WILL INCREASE THURSDAY/FRIDAY. && .FIRE WEATHER... SUNDAY...NORTHWEST/DOWNSLOPE WINDS WILL GUST TO 30-35 MPH AS MINIMUM RELATIVE HUMIDITY AVERAGES 20 TO 30 PERCENT. PER COLLABORATION WITH FIRE WEATHER PARTNERS...NO FIRE WEATHER WATCHES/RED FLAG WARNINGS ARE NEEDED DUE TO ELEVATED FUEL MOISTURE PRODUCED BY RECENT RAINFALL. && .CHS WATCHES/WARNINGS/ADVISORIES... GA...NONE. SC...LAKE WIND ADVISORY UNTIL MIDNIGHT EDT SUNDAY NIGHT FOR SCZ045. MARINE...DENSE FOG ADVISORY UNTIL 10 PM EDT THIS EVENING FOR AMZ350-352. SMALL CRAFT ADVISORY UNTIL 6 PM EDT SUNDAY FOR AMZ352-354. SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT SUNDAY NIGHT FOR AMZ330-350. GALE WARNING UNTIL 6 PM EDT SUNDAY FOR AMZ374. && $$ ST
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
1103 AM EDT SAT MAR 29 2014 .SYNOPSIS... A COLD FRONT WILL MOVE THROUGH THE AREA THIS EVENING...THEN DRY HIGH PRESSURE WILL BUILD INTO THE REGION THROUGH THURSDAY. A COLD FRONT WILL MOVE THROUGH NEXT FRIDAY OR FRIDAY NIGHT BEFORE HIGH PRESSURE REBUILDS NEXT WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... LATE THIS MORNING...THE FORECAST AREA IS NOW LARGELY PRECIPITATION FREE AS THE HEAVY OVERNIGHT RAINFALL HAS ENDED AND PUSHED OFF TO THE EAST. THERE IS AN AREA OF WEAKENING RETURNS ATTEMPTING TO MOVE IN FROM THE WEST...BUT THIS HAS BEEN ON A DISTINCT DOWNWARD TREND OVER THE PAST FEW HOURS AND SHOULD AMOUNT TO VERY LITTLE ACROSS SOUTHEAST GEORGIA. THE MAIN STORY FOR TODAY REVOLVES AROUND THE COLD FRONT TO THE WEST AND ITS EVENTUAL IMPACT ON THE FORECAST AREA LATER THIS AFTERNOON. BASED ON MORNING SURFACE ANALYSIS AND CURRENT REGIONAL OBSERVATIONS...THE FRONT HAS PUSHED THROUGH BIRMINGHAM AND WILL CONTINUE TO PROGRESS QUICKLY EASTWARD. THE FRONT IS POSITIONED WITHIN THE UPPER LEVEL SYSTEM WHERE A DISTINCT MID/UPPER LEVEL DRY SLOT IS RAPIDLY IMPINGING IN FROM THE WEST. THE DRIER AIR ALOFT...ACCORDING TO WATER VAPOR IMAGERY...IS NOW BEGINNING TO MOVE INTO GEORGIA AND WILL REACH OUR AREA BY THE AFTERNOON. THERE CONTINUES TO BE CONSIDERABLE CLOUD COVER ACROSS MOST OF THE REGION...THOUGH VISIBLE SATELLITE SHOWS AN AREA OF CLEARING AHEAD OF THE FRONT THAT IS NOW ENTERING CENTRAL GEORGIA. IN ADDITION TO THE UNCERTAIN CLOUD COVER FORECAST TODAY...ANOTHER COMPLICATING FACTOR IS THE AREA OF CONSOLIDATING CONVECTION OVER NORTH FLORIDA AND THE NORTHEASTERN GULF OF MEXICO. BACK TO OUR WEST...RADAR IMAGERY IS PRIMARILY CLEAN SO IT APPEARS IT WILL REQUIRE SOME SURFACE HEATING AND SURFACE INSTABILITY DEVELOPMENT FOR SHOWERS AND THUNDERSTORMS TO START THERE. ONE OF THE MAIN QUESTIONS IS TO WHAT DEGREE DOES THE CONVECTION TO THE SOUTH INTERRUPT NORTHWARD MOISTURE TRANSPORT AND IMPACT COVERAGE/INTENSITY OF DEVELOPMENT ACROSS THE FORECAST AREA THIS AFTERNOON. HI-RES MODELS SEEM TO BE CAPTURING THE CURRENT PICTURE THE BEST. THE RAP KEEP THE HEAVIEST PRECIPITATION WELL TO OUR SOUTH WITH ONLY VERY MINIMAL DEVELOPMENT ALONG THE FRONT IN THE MID TO LATE AFTERNOON HOURS. LOOKING AT SOME RAP SOUNDINGS SHOWS THAT THERE IS A CAP IN PLACE THIS AFTERNOON ACROSS MUCH OF THE AREA. HOWEVER...THIS SHOULD EASILY BE OVERCOME IF WE ARE ABLE TO GET SOME SUN AND WARM UP. LOW LEVEL THICKNESS VALUES WOULD SUPPORT TEMPS IN THE LOW 80S...SO ANY BREAKS IN THE CLOUD COVER WOULD LIKELY RESULT IN RAPID TEMPERATURE RISES. THE MAX TEMP FORECAST HAS BEEN ADJUSTED A BIT...BUT I STILL THINK WE WILL SEE MID/UPPER 70S IN MOST AREAS. TEMPS GETTING INTO THE LOW 70S WILL LIKELY YIELD CAPE VALUES SOMEWHERE IN THE NEIGHBORHOOD OF 1000-1200 J/KG THIS AFTERNOON. SO I THINK WE WILL SEE SCATTERED THUNDERSTORMS...BUT THE OVERALL MODEL REPRESENTATION WOULD SUPPORT ONLY MODEST UPDRAFTS. DEEP LAYER SHEAR CERTAINLY INCREASES WITH 0-6 KM VALUE INTO THE 50 KT RANGE SO THE AMBIENT ENVIRONMENT WOULD SUPPORT A SEVERE THUNDERSTORM OR TWO. BUT... IT APPEARS LESS LIKELY THAT THE SEVERE THREAT WILL BECOME VERY WIDESPREAD GIVEN THE CLOUD COVER AND POTENTIAL FOR INSTABILITY TO BE LACKING. OVERNIGHT...THE CLOSED UPPER LOW WILL MOVE ACROSS THE SOUTHERN MID-ATLANTIC REGION...WITH THE SURFACE LOW LIFTING NORTHEAST TO THE MID-ATLANTIC COAST AND ITS TRAILING COLD FRONT PUSHING WELL OFF THE SOUTHEAST COAST. SIGNIFICANT DRYING WILL OCCUR...WITH STRONG COLD AIR ADVECTION IN WAKE OF THE FRONT CAUSING BREEZY CONDITIONS TO DEVELOP AND TEMPERATURES TO DROP OFF LATE TO LOWS IN THE MID TO UPPER 40S WITH SOME LOWER 50S NEAR THE IMMEDIATE COAST. LAKE WINDS...A LAKE WIND ADVISORY HAS BEEN ISSUED FOR LAKE MOULTRIE BEGINNING AFTER MIDNIGHT AS STRONG COLD AIR ADVECTION DEVELOPS IN WAKE OF A DEPARTING COLD FRONT. && .SHORT TERM /SUNDAY THROUGH TUESDAY/... DRY HIGH PRESSURE WILL SURGE INTO THE AREA ON SUNDAY AS THE UPPER LEVEL RIDGE TAKES HOLD. ALTHOUGH WEAK COLD ADVECTION IS FORECAST... STRONG 35-40 KT DOWNSLOPE FLOW CENTERED AROUND 850 MB WILL PRODUCE CONSIDERABLE ADIABATIC HEATING. HIGH TEMPERATURES WILL CLIMB INTO THE LOWER 70S IN SOUTHEAST GA WITH UPPER 60S ELSEWHERE. MODEL SOUNDINGS INDICATE A NEARLY 6000 FT MIXED LAYER DURING THE DAYTIME HOURS. WITH GEOSTROPHIC WINDS PROGGED AT 35-40 KT THIS WILL YIELD WINDY CONDITIONS WITH SUSTAINED WINDS OF 15-20 KT AND SOME GUSTS APPROACHING 30 KT. WINDS WILL CALM DOWN SUNDAY EVENING. AS THE SURFACE HIGH BUILDS IN SUNDAY NIGHT...CLEAR SKIES AND DIMINISHING WINDS SUPPORT FAIRLY GOOD RADIATIONAL COOLING OVERNIGHT. MONDAY MORNING LOWS COULD DROP INTO THE UPPER 30S FAR INLAND WITH LOWER 40S MOST EVERYWHERE ELSE. MONDAY THROUGH TUESDAY A STRONG DEEP LAYERED RIDGE WILL BUILD OVER THE SOUTHEAST UNITED STATES...PROVIDING INCREASING LOW-LEVEL THICKNESSES AND AMPLE SUNSHINE. HIGH TEMPS WILL WARM INTO THE MID/UPPER 70S ON MONDAY AND LIKELY INTO THE LOWER 80S ON TUESDAY. && .LONG TERM /TUESDAY NIGHT THROUGH FRIDAY/... DEEP LAYERED RIDGING WILL PERSIST TUESDAY NIGHT THROUGH THURSDAY NIGHT WITH ABOVE NORMAL TEMPERATURES AND DRY CONDITIONS. A PROGRESSIVE UPPER LOW WILL MOVE THROUGH THE OHIO VALLEY LATE IN THE WEEK...PUSHING A COLD FRONT THROUGH THE AREA FRIDAY OR FRIDAY NIGHT. THIS MAY BRING A FEW SHOWERS AND THUNDERSTORMS TO THE AREA BEFORE DRY HIGH PRESSURE REBUILDS NEXT WEEKEND. && .AVIATION /15Z SATURDAY THROUGH WEDNESDAY/... KCHS...CEILINGS WILL CONTINUE ALTERNATE BETWEEN IFR AND MVFR FOR ANOTHER FEW HOURS AND THE FORECAST HAS BEEN AMENDED ACCORDINGLY. THEN...CEILINGS SHOULD LIFT TO PREVAILING MVFR LEVELS...WITH FURTHER IMPROVEMENT TO VFR LEVELS AFTER 19Z. SHOWERS AND PERHAPS A FEW THUNDERSTORMS ARE EXPECTED TO IMPACT THE TERMINAL AHEAD OF AN APPROACHING COLD FRONT IN THE 22-02Z TIME FRAME...TEMPORARILY REDUCING CEILINGS AND/OR VISIBILITIES. BREEZY SOUTHWEST TO WEST WINDS ARE EXPECTED BEGINNING THIS AFTERNOON AND CONTINUING THROUGH THE END OF THE FORECAST PERIOD...WITH GUSTS UPWARDS OF AROUND 20 KT. KSAV...CEILINGS WILL CONTINUE TO ALTERNATE BETWEEN IFR AND MVFR FOR ANOTHER FEW HOURS...BEFORE LIFTING TO VFR LEVELS AFTER 16Z. SHOWERS AND PERHAPS A FEW THUNDERSTORMS ARE EXPECTED TO IMPACT THE TERMINAL AHEAD OF AN APPROACHING COLD FRONT IN THE 21-01Z TIME FRAME...TEMPORARILY REDUCING CEILINGS AND/OR VISIBILITIES. BREEZY SOUTHWEST TO WEST WINDS ARE EXPECTED BEGINNING THIS AFTERNOON AND CONTINUING THROUGH THE END OF THE FORECAST PERIOD...WITH GUSTS UPWARDS OF 20-25 KT. EXTENDED AVIATION OUTLOOK...VFR CONDITIONS EXPECTED. WINDY CONDITIONS AT BOTH TERMINALS ON SUNDAY. && .MARINE... TODAY AND TONIGHT...A SOUTH TO SOUTHWEST FLOW WILL STRENGTHEN THROUGH THIS EVENING AHEAD OF AN APPROACHING COLD FRONT. WINDS WILL THEN VEER WEST-NORTHWEST LATE THIS EVENING AND OVERNIGHT AS THE FRONT SHIFTS OFFSHORE...WITH STRONG COLD AIR ADVECTION DEVELOPING IN WAKE OF THE FRONT. SMALL CRAFT ADVISORIES ARE ALREADY IN EFFECT FOR THE NEAR SHORE SC WATERS AND THE OUTER GA WATERS FOR SEAS OF 6 FT OR GREATER DUE TO PERSISTENT SOUTHEAST SWELL...BUT ALL WATERS INCLUDING CHARLESTON HARBOR WILL BE UNDER A SMALL CRAFT ADVISORY LATER TONIGHT DUE TO ELEVATED WINDS AND/OR SEAS. THERE IS EVEN A LOW PROBABILITY OF WINDS BRIEFLY GUSTING TO GALE FORCE IN THE OUTER GA WATERS LATE TONIGHT. CONDITIONS WILL REMAIN FAVORABLE FOR SEA FOG UNTIL THE COLD FRONT CROSSES THE WATERS WITH MUCH DRIER AIR THIS EVENING. THE FORECAST INDICATES PATCHY FOG...BUT MORE WIDESPREAD FOG COULD PROMPT DENSE FOG MARINE ADVISORIES. SUNDAY THROUGH WEDNESDAY...ELEVATED WINDS/SEAS WILL PERSIST THROUGH SUNDAY...THEN TAPER OFF THROUGH SUNDAY NIGHT AS THE SURFACE HIGH BUILDS OVER THE WATERS. SMALL CRAFT ADVISORIES ARE IN EFFECT FOR ALL MARINE ZONES ON SUNDAY BEFORE DROPPING OFF BY MIDNIGHT. FAIRLY QUIET CONDITIONS THEN EXPECTED THROUGH WEDNESDAY NIGHT BEFORE A SOUTHERLY JET INCREASES WINDS AND SEAS THURSDAY INTO FRIDAY AHEAD OF A COLD FRONT. MARINE FLAGS WILL BE POSSIBLE AGAIN THURSDAY/FRIDAY. && .FIRE WEATHER... ON SUNDAY...AS THE UPPER RIDGE BEGINS TO BUILD INTO THE AREA... DOWNSLOPE SUBSIDENCE WILL STRETCH THE MIXED LAYER TO ABOUT 6000 FT. THIS WILL ALLOW DEWPOINTS TO MIX DOWN INTO THE 30S DURING THE DAY WHILE ALSO TAPPING INTO FAIRLY STRONG WINDS ALOFT. CURRENT MINIMUM RH FORECAST SHOWS MID/UPPER 20S ON SUNDAY WITH NW WINDS OF 15 TO 20 MPH WITH SOME GUSTS AS HIGH AS 30 MPH. THE FUELS WILL PROBABLY BE TOO WET FROM ONGOING RAIN TO MAKE FOR A SIGNIFICANT FIRE DANGER THOUGH CONDITIONS WILL NEED TO BE MONITORED. && .CHS WATCHES/WARNINGS/ADVISORIES... GA...NONE. SC...LAKE WIND ADVISORY FROM MIDNIGHT TONIGHT TO MIDNIGHT EDT SUNDAY NIGHT FOR SCZ045. MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT SUNDAY FOR AMZ352. SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT SUNDAY NIGHT FOR AMZ350-374. SMALL CRAFT ADVISORY FROM MIDNIGHT TONIGHT TO 6 PM EDT SUNDAY FOR AMZ354. SMALL CRAFT ADVISORY FROM MIDNIGHT TONIGHT TO MIDNIGHT EDT SUNDAY NIGHT FOR AMZ330. && $$ SYNOPSIS... NEAR TERM...BSH SHORT TERM...JRL LONG TERM...JRL AVIATION...JAQ/JRL MARINE...JAQ/JRL FIRE WEATHER...
AREA FORECAST DISCUSSION...UPDATED
NWS PEACHTREE CITY GA
940 AM EDT SAT MAR 29 2014 .UPDATE... LATEST MODEL GUIDANCE IS SUGGESTING THE DIMINISHING PRECIP OVER THE CWA WILL CONTINUE WITH THE MORE WIDESPREAD AREA OF SHOWERS REMAINING ACROSS EXTREME NORTH GEORGIA AND SCATTERED SHOWERS DEVELOPING ELSEWHERE. THE PRECIP WILL END FROM THE WEST THIS AFTERNOON AS DRIER AIR SPREADS INTO THE CWA. THERE REMAINS A SLIGHT RISK OF THUNDERSTORMS OVER THE SOUTHEASTERN PART OF THE CWA. HAVE THEREFORE ADJUSTED POPS FOR THE REST OF TODAY. NO OTHER CHANGES PLANNED. 17 && .PREV DISCUSSION... /ISSUED 339 AM EDT SAT MAR 29 2014/ SHORT TERM /TODAY THROUGH SUNDAY/... 500MB ANALYSIS SHOWS A POTENT SHORTWAVE ACROSS CENTRAL MS EARLY THIS MORNING. THIS FEATURE IS ASSOCIATED WITH AN MCS MOVING INTO WESTERN AL. THE CONVECTIVE ACTIVITY HAS DEVELOPED PRETTY FAR AHEAD OF THE COLD FRONT WHICH IS CURRENTLY STILL ACROSS THE ARKLATEX ALONG WITH THE DEVELOPING WAVE OF LOW PRESSURE. THE SHORTWAVE WILL CONTINUE EAST TODAY AND MOVE ACROSS GA DURING THE FIRST PART OF THE DAY. THE ASSOCIATED COLD POOL WILL STEEPEN MID LEVEL LAPSE RATES SIGNIFICANTLY. THE HRRR SEEMS TO HAVE A DECENT HANDLE ON THE CONVECTIVE ACTIVITY TO THE WEST AND HAVE FOLLOWED FAIRLY CLOSELY FOR POPS. THE MAIN ISSUE WILL BE THE POTENTIAL FOR SEVERE. STILL THINK THE BEST POTENTIAL FOR SEVERE WILL BE THE EXTREME SOUTHEAST PORTION OF THE CWFA. HOWEVER...ANOTHER THING TO CONSIDER WILL BE THE MOVEMENT OF THE ACTIVITY ACROSS EASTERN MS/WESTERN AL. IF THE MCS CONTINUES TO SHIFT TO THE SE...THIS COULD HELP LIMIT THE DEVELOPMENT OF WIDESPREAD CONVECTION ACROSS THE CWFA. NEWEST RUNS OF THE HRRR DO TAKE THE STRONGEST ACTIVITY ACROSS SOUTHERN GA AND THE FLORIDA PANHANDLE DURING THE MORNING HOURS. THIS WOULD MEAN THAT A FEW STRONG/ISOLATED SEVERE STORMS...ARE POSSIBLE ACROSS THE EXTREME SOUTHERN PART OF THE CWFA. IN ADDITION...BEHIND THE INITIAL MCS BUT STILL AHEAD OF THE COLD FRONT...THE HRRR HAS SCATTERED THUNDERSTORMS BREAKING OUT ACROSS THE SE...SO THE POTENTIAL FOR STRONG STORMS/ISOLD SEVERE MAY LAST INTO THE MID TO LATE AFTERNOON HOURS...WHEN THERE IS MORE POTENTIAL FOR BREAKS IN THE CLOUDS AND FOR SURFACE DESTABILIZATION TO OCCUR. LUCKILY...SHEAR VALUES ARE RATHER WEAK...WITH THE BEST VALUES ALONG THE LAGGING COLD FRONT THIS EVENING. IF SEVERE THUNDERSTORMS ARE ABLE TO DEVELOP...DAMAGING WIND GUSTS AND LARGE HAIL WOULD BE THE PRIMARY THREATS. THE HRRR DOES CLEAR OUT THE POPS A BIT FASTER THAN PREVIOUSLY FORECAST. HAVE TRIED TO ACCOUNT FOR THIS IN TIMING. TEMPS IN THE NE WILL DIP DOWN INTO THE MIDDLE 30S TONIGHT...BUT LUCKILY...THE FORECAST SHOULD BE DRY. TOO MARGINAL TO ISSUE A FREEZE WATCH...AND THE WINDS MAY STAY UP OVERNIGHT JUST ENOUGH TO LIMIT FROST DEVELOPMENT. NLISTEMAA LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/... HIGH PRESSURE DOMINATES FOR THE BEGINNING OF THE EXTENDED. A WEAK FRONT APPROACHES THE AREA ON TUESDAY BUT THE PRECIPITATION ASSOCIATED WITH IT SHOULD DIMINISH BEFORE REACHING THE STATE. SYSTEM OF INTEREST IN THE EXTENDED THOUGH IS NEAR THE END. BOTH THE ECMWF AND THE GFS LIFT A SFC LOW OUT OF THE MIDWEST AND INTO THE OHIO VALLEY/GREAT LAKES REGION ON FRIDAY AND PUSHES SHOWERS AND THUNDERSTORMS ACROSS THE CWA AHEAD OF A COLD FRONT THATS PROGGED TO MOVE THROUGH FRIDAY NIGHT. STILL SOME DIFFERENCES BETWEEN THE TWO MODELS IN TERMS OF FEATURE LOCATIONS...BUT OVERALL BOTH SUGGEST A GOOD CHANCE OF SHOWERS AND THUNDERSTORMS LATE IN THE WEEK. WILL HAVE TO CAREFULLY MONITOR FRIDAY FOR SEVERE WEATHER POTENTIAL AS THE GFS INDICATES UP TO 2000 J/KG OF MUCAPE ON FRIDAY WITH 30-40KTS OF LOW LEVEL SHEAR. 11 && .AVIATION... 12Z UPDATE... LOW PRESSURE AND COLD FRONT CURRENTLY ACROSS CETRAL MS EARLY THIS MORNING. THE FRONT AND LOW CENTER WILL MOVE EAST THROUGH THE DAY...AND FINALLY EAST OF THE REGION EARLY THIS EVENING. MCS THAT DEVELOPED AHEAD OF THE BOUNDARY HAS WEAKENED CONSIDERABLY OVER THE LAST FEW HOURS...WITH THE LIGHTNING DYING OFF. AM STILL A LITTLE CONCERNED WITH RE-DEVELOPMENT OF SHOWERS BETWEEN THE EXITING MCS AND THE APPROACHING COLD FRONT. WINDS SHOULD GO W BY MID MORNING...AND EVENTUALLY NW THIS EVENING. //ATL CONFIDENCE...12Z UPDATE... MEDIUM CONFIDENCE ALL ELEMENTS. && .PRELIMINARY POINT TEMPS/POPS... ATHENS 66 39 66 37 / 100 20 0 0 ATLANTA 65 39 64 42 / 100 10 0 0 BLAIRSVILLE 59 33 57 32 / 100 30 0 0 CARTERSVILLE 62 37 64 34 / 90 10 0 0 COLUMBUS 69 42 68 42 / 100 10 0 0 GAINESVILLE 63 38 64 40 / 100 20 0 0 MACON 70 42 67 37 / 100 10 0 0 ROME 62 37 65 34 / 80 10 0 0 PEACHTREE CITY 66 38 65 34 / 100 10 0 0 VIDALIA 72 45 69 41 / 80 30 0 0 && .FFC WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
737 AM EDT SAT MAR 29 2014 .PREV DISCUSSION... /ISSUED 339 AM EDT SAT MAR 29 2014/ SHORT TERM /TODAY THROUGH SUNDAY/... 500MB ANALYSIS SHOWS A POTENT SHORTWAVE ACROSS CENTRAL MS EARLY THIS MORNING. THIS FEATURE IS ASSOCIATED WITH AN MCS MOVING INTO WESTERN AL. THE CONVECTIVE ACTIVITY HAS DEVELOPED PRETTY FAR AHEAD OF THE COLD FRONT WHICH IS CURRENTLY STILL ACROSS THE ARKLATEX ALONG WITH THE DEVELOPING WAVE OF LOW PRESSURE. THE SHORTWAVE WILL CONTINUE EAST TODAY AND MOVE ACROSS GA DURING THE FIRST PART OF THE DAY. THE ASSOCIATED COLD POOL WILL STEEPEN MID LEVEL LAPSE RATES SIGNIFICANTLY. THE HRRR SEEMS TO HAVE A DECENT HANDLE ON THE CONVECTIVE ACTIVITY TO THE WEST AND HAVE FOLLOWED FAIRLY CLOSELY FOR POPS. THE MAIN ISSUE WILL BE THE POTENTIAL FOR SEVERE. STILL THINK THE BEST POTENTIAL FOR SEVERE WILL BE THE EXTREME SOUTHEAST PORTION OF THE CWFA. HOWEVER...ANOTHER THING TO CONSIDER WILL BE THE MOVEMENT OF THE ACTIVITY ACROSS EASTERN MS/WESTERN AL. IF THE MCS CONTINUES TO SHIFT TO THE SE...THIS COULD HELP LIMIT THE DEVELOPMENT OF WIDESPREAD CONVECTION ACROSS THE CWFA. NEWEST RUNS OF THE HRRR DO TAKE THE STRONGEST ACTIVITY ACROSS SOUTHERN GA AND THE FLORIDA PANHANDLE DURING THE MORNING HOURS. THIS WOULD MEAN THAT A FEW STRONG/ISOLATED SEVERE STORMS...ARE POSSIBLE ACROSS THE EXTREME SOUTHERN PART OF THE CWFA. IN ADDITION...BEHIND THE INITIAL MCS BUT STILL AHEAD OF THE COLD FRONT...THE HRRR HAS SCATTERED THUNDERSTORMS BREAKING OUT ACROSS THE SE...SO THE POTENTIAL FOR STRONG STORMS/ISOLD SEVERE MAY LAST INTO THE MID TO LATE AFTERNOON HOURS...WHEN THERE IS MORE POTENTIAL FOR BREAKS IN THE CLOUDS AND FOR SURFACE DESTABILIZATION TO OCCUR. LUCKILY...SHEAR VALUES ARE RATHER WEAK...WITH THE BEST VALUES ALONG THE LAGGING COLD FRONT THIS EVENING. IF SEVERE THUNDERSTORMS ARE ABLE TO DEVELOP...DAMAGING WIND GUSTS AND LARGE HAIL WOULD BE THE PRIMARY THREATS. THE HRRR DOES CLEAR OUT THE POPS A BIT FASTER THAN PREVIOUSLY FORECAST. HAVE TRIED TO ACCOUNT FOR THIS IN TIMING. TEMPS IN THE NE WILL DIP DOWN INTO THE MIDDLE 30S TONIGHT...BUT LUCKILY...THE FORECAST SHOULD BE DRY. TOO MARGINAL TO ISSUE A FREEZE WATCH...AND THE WINDS MAY STAY UP OVERNIGHT JUST ENOUGH TO LIMIT FROST DEVELOPMENT. NLISTEMAA LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/... HIGH PRESSURE DOMINATES FOR THE BEGINNING OF THE EXTENDED. A WEAK FRONT APPROACHES THE AREA ON TUESDAY BUT THE PRECIPITATION ASSOCIATED WITH IT SHOULD DIMINISH BEFORE REACHING THE STATE. SYSTEM OF INTEREST IN THE EXTENDED THOUGH IS NEAR THE END. BOTH THE ECMWF AND THE GFS LIFT A SFC LOW OUT OF THE MIDWEST AND INTO THE OHIO VALLEY/GREAT LAKES REGION ON FRIDAY AND PUSHES SHOWERS AND THUNDERSTORMS ACROSS THE CWA AHEAD OF A COLD FRONT THATS PROGGED TO MOVE THROUGH FRIDAY NIGHT. STILL SOME DIFFERENCES BETWEEN THE TWO MODELS IN TERMS OF FEATURE LOCATIONS...BUT OVERALL BOTH SUGGEST A GOOD CHANCE OF SHOWERS AND THUNDERSTORMS LATE IN THE WEEK. WILL HAVE TO CAREFULLY MONITOR FRIDAY FOR SEVERE WEATHER POTENTIAL AS THE GFS INDICATES UP TO 2000 J/KG OF MUCAPE ON FRIDAY WITH 30-40KTS OF LOW LEVEL SHEAR. 11 && .AVIATION... 12Z UPDATE... LOW PRESSURE AND COLD FRONT CURRENTLY ACROSS CETRAL MS EARLY THIS MORNING. THE FRONT AND LOW CENTER WILL MOVE EAST THROUGH THE DAY...AND FINALLY EAST OF THE REGION EARLY THIS EVENING. MCS THAT DEVELOPED AHEAD OF THE BOUNDARY HAS WEAKENED CONSIDERABLY OVER THE LAST FEW HOURS...WITH THE LIGHTNING DYING OFF. AM STILL A LITTLE CONCERNED WITH RE-DEVELOPMENT OF SHOWERS BETWEEN THE EXITING MCS AND THE APPROACHING COLD FRONT. WINDS SHOULD GO W BY MID MORNING...AND EVENTUALLY NW THIS EVENING. //ATL CONFIDENCE...12Z UPDATE... MEDIUM CONFIDENCE ALL ELEMENTS. && .PRELIMINARY POINT TEMPS/POPS... ATHENS 66 39 66 37 / 100 20 0 0 ATLANTA 65 39 64 42 / 100 10 0 0 BLAIRSVILLE 59 33 57 32 / 100 30 0 0 CARTERSVILLE 62 37 64 34 / 90 10 0 0 COLUMBUS 69 42 68 42 / 100 10 0 0 GAINESVILLE 63 38 64 40 / 100 20 0 0 MACON 70 42 67 37 / 100 10 0 0 ROME 62 37 65 34 / 80 10 0 0 PEACHTREE CITY 66 38 65 34 / 100 10 0 0 VIDALIA 72 45 69 41 / 80 30 0 0 && .FFC WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
637 AM EDT SAT MAR 29 2014 .SYNOPSIS... MOISTURE WILL BE HIGH AHEAD OF A COLD FRONT. THE FRONT WILL MOVE THROUGH THE FORECAST AREA THIS EVENING. HIGH PRESSURE AND DRY CONDITIONS WILL PREVAIL SUNDAY AND MONDAY. && .NEAR TERM /THROUGH TONIGHT/... ISENTROPIC LIFT WILL SUPPORT NUMEROUS SHOWERS EARLY THIS MORNING. THE MESOSCALE CONVECTIVE COMPLEX APPROACHING THE FORECAST AREA FROM THE WEST SHOULD REACH THE AREA LATE THIS MORNING. RADAR TRENDS AND THE LATEST HRRR INDICATE THE STRONGER CONVECTION WILL REMAIN SOUTH OF THE AREA. STRONGER CONVERGENCE AHEAD OF THE COLD FRONT SHOULD BEGIN TO ENTER THE FORECAST AREA FROM THE WEST AROUND THE MIDDLE OF THE AFTERNOON. SHEAR WILL BE HIGH WITH H85 WINDS OF 30 TO 40 KNOTS SUPPORTING POSSIBLE SEVERE THUNDERSTORMS. THE THREAT APPEARS LIMITED BECAUSE IT IS QUESTIONABLE HOW MUCH MOISTURE AND INSTABILITY RECOVERY WILL OCCUR IN THE WAKE OF THE LARGE COMPLEX THIS MORNING. THE THREAT OF THUNDERSTORMS WILL CONTINUE INTO THE EVENING WITH THE COLD FRONT IN THE AREA AND COOLING ALOFT ASSOCIATED WITH THE UPPER-LEVEL TROUGH. DRYING SHOULD OCCUR LATER IN THE EVENING BEHIND THE COLD FRONT. USED THE GUIDANCE CONSENSUS FOR THE TEMPERATURE FORECAST. && .SHORT TERM /SUNDAY THROUGH SUNDAY NIGHT/... HIGH PRESSURE WILL BUILD OVER THE AREA SUNDAY THROUGH SUNDAY NIGHT. IT WILL BE BREEZY SUNDAY AND A LAKE WIND ADVISORY WILL LIKELY BE NEEDED. THE GFS AND NAM MOS SUPPORT WINDS OF 15 TO 25 KNOTS. WINDS SHOULD DIMINISH SUNDAY NIGHT AS THE HIGH GETS CLOSER TO THE AREA AND THE PRESSURE GRADIENT WEAKENS. STRONG NET RADIATIONAL COOLING CONDITIONS SHOULD DEVELOP LATE. USED THE GUIDANCE CONSENSUS FOR THE TEMPERATURE FORECAST. EXPECT LOWS IN THE MID AND UPPER 30S SUNDAY NIGHT WITH SCATTERED FROST. A FROST ADVISORY MAY BE NEEDED. && .LONG TERM /MONDAY THROUGH FRIDAY/... THE GFS AND ECMWF INDICATE DRY HIGH PRESSURE SHOULD DOMINATE DURING MUCH OF THE PERIOD. MOISTURE SHOULD BE ON THE INCREASE LATE IN THE PERIOD AHEAD OF A COLD FRONT. WARMER TEMPERATURES SHOULD OCCUR AS THE HIGH SHIFTS EASTWARD AND THE AIR MASS CONTINUES TO MODIFY. THE GFS...ECMWF... AND EKD MOS SUPPORT HIGHS IN THE UPPER 70S TO AROUND 80. && .AVIATION /12Z SATURDAY THROUGH WEDNESDAY/... SHOWERS ACROSS THE MIDLANDS AND CSRA ARE DIMINISHING FROM THE WEST THIS MORNING. ABUNDANT LOW-LEVEL MOISTURE THIS MORNING HAS CONTRIBUTED TO IFR/LIFR CIGS WITH SOME IFR VSBYS. MVFR CONDITIONS EXPECTED TO RETURN AROUND 16Z AS SOUTHERLY WINDS INCREASE AHEAD OF THE APPROACHING COLD FRONT. THERE SHOULD BE AN AREA SHOWERS/FEW TSTMS TO CROSS THE TAF SITES DURING THE AFTERNOON AHEAD OF THE COLD FRONT. THE COLD FRONT WILL CROSS THE TAF SITES BY EARLY EVENING. VFR CONDITIONS ACROSS THE AREA BY THE END OF THE TAF PERIOD. EXTENDED AVIATION OUTLOOK...BREEZY CONDITIONS OVER THE AREA POSSIBLE IN THE WAKE OF THE FRONT SUNDAY. && .CAE WATCHES/WARNINGS/ADVISORIES... SC...NONE. GA...NONE. && $$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
625 AM EDT SAT MAR 29 2014 .SYNOPSIS... MOISTURE WILL BE HIGH AHEAD OF A COLD FRONT. THE FRONT WILL MOVE THROUGH THE FORECAST AREA THIS EVENING. HIGH PRESSURE AND DRY CONDITIONS WILL PREVAIL SUNDAY AND MONDAY. && .NEAR TERM /THROUGH TONIGHT/... ISENTROPIC LIFT WILL SUPPORT NUMEROUS SHOWERS EARLY THIS MORNING. THE MESOSCALE CONVECTIVE COMPLEX APPROACHING THE FORECAST AREA FROM THE WEST SHOULD REACH THE AREA LATE THIS MORNING. RADAR TRENDS AND THE LATEST HRRR INDICATE THE STRONGER CONVECTION WILL REMAIN SOUTH OF THE AREA. STRONGER CONVERGENCE AHEAD OF THE COLD FRONT SHOULD BEGIN TO ENTER THE FORECAST AREA FROM THE WEST AROUND THE MIDDLE OF THE AFTERNOON. SHEAR WILL BE HIGH WITH H85 WINDS OF 30 TO 40 KNOTS SUPPORTING POSSIBLE SEVERE THUNDERSTORMS. THE THREAT APPEARS LIMITED BECAUSE IT IS QUESTIONABLE HOW MUCH MOISTURE AND INSTABILITY RECOVERY WILL OCCUR IN THE WAKE OF THE LARGE COMPLEX THIS MORNING. THE THREAT OF THUNDERSTORMS WILL CONTINUE INTO THE EVENING WITH THE COLD FRONT IN THE AREA AND COOLING ALOFT ASSOCIATED WITH THE UPPER-LEVEL TROUGH. DRYING SHOULD OCCUR LATER IN THE EVENING BEHIND THE COLD FRONT. USED THE GUIDANCE CONSENSUS FOR THE TEMPERATURE FORECAST. && .SHORT TERM /SUNDAY THROUGH SUNDAY NIGHT/... HIGH PRESSURE WILL BUILD OVER THE AREA SUNDAY THROUGH SUNDAY NIGHT. IT WILL BE BREEZY SUNDAY AND A LAKE WIND ADVISORY WILL LIKELY BE NEEDED. THE GFS AND NAM MOS SUPPORT WINDS OF 15 TO 25 KNOTS. WINDS SHOULD DIMINISH SUNDAY NIGHT AS THE HIGH GETS CLOSER TO THE AREA AND THE PRESSURE GRADIENT WEAKENS. STRONG NET RADIATIONAL COOLING CONDITIONS SHOULD DEVELOP LATE. USED THE GUIDANCE CONSENSUS FOR THE TEMPERATURE FORECAST. EXPECT LOWS IN THE MID AND UPPER 30S SUNDAY NIGHT WITH SCATTERED FROST. A FROST ADVISORY MAY BE NEEDED. && .LONG TERM /MONDAY THROUGH FRIDAY/... THE GFS AND ECMWF INDICATE DRY HIGH PRESSURE SHOULD DOMINATE DURING MUCH OF THE PERIOD. MOISTURE SHOULD BE ON THE INCREASE LATE IN THE PERIOD AHEAD OF A COLD FRONT. WARMER TEMPERATURES SHOULD OCCUR AS THE HIGH SHIFTS EASTWARD AND THE AIR MASS CONTINUES TO MODIFY. THE GFS...ECMWF... AND EKD MOS SUPPORT HIGHS IN THE UPPER 70S TO AROUND 80. && .AVIATION /12Z SATURDAY THROUGH WEDNESDAY/... SHOWERS ACROSS THE MIDLANDS AND CSRA ARE DIMINISHING FROM THE WEST THIS MORNING. ABUNDANT LOW-LEVEL MOISTURE THIS MORNING HAS CONTRIBUTED TO IFR/LIFR CIGS. MVFR CONDITIONS EXPECTED TO RETURN AROUND 16Z AS SOUTHERLY WINDS INCREASE AHEAD OF THE APPROACHING COLD FRONT. THERE SHOULD BE AN AREA SHOWERS/FEW TSTMS TO CROSS THE TAF SITES DURING THE AFTERNOON AHEAD OF THE COLD FRONT. THE COLD FRONT WILL CROSS THE TAF SITES BY EARLY EVENING. VFR CONDITIONS ACROSS THE AREA BY THE END OF THE TAF PERIOD. EXTENDED AVIATION OUTLOOK...BREEZY CONDITIONS OVER THE AREA POSSIBLE IN THE WAKE OF THE FRONT SUNDAY. && .CAE WATCHES/WARNINGS/ADVISORIES... SC...NONE. GA...NONE. && $$
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
339 AM EDT SAT MAR 29 2014 .SHORT TERM /TODAY THROUGH SUNDAY/... 500MB ANALYSIS SHOWS A POTENT SHORTWAVE ACROSS CENTRAL MS EARLY THIS MORNING. THIS FEATURE IS ASSOCIATED WITH AN MCS MOVING INTO WESTERN AL. THE CONVECTIVE ACTIVITY HAS DEVELOPED PRETTY FAR AHEAD OF THE COLD FRONT WHICH IS CURRENTLY STILL ACROSS THE ARKLATEX ALONG WITH THE DEVELOPING WAVE OF LOW PRESSURE. THE SHORTWAVE WILL CONTINUE EAST TODAY AND MOVE ACROSS GA DURING THE FIRST PART OF THE DAY. THE ASSOCIATED COLD POOL WILL STEEPEN MID LEVEL LAPSE RATES SIGNIFICANTLY. THE HRRR SEEMS TO HAVE A DECENT HANDLE ON THE CONVECTIVE ACTIVITY TO THE WEST AND HAVE FOLLOWED FAIRLY CLOSELY FOR POPS. THE MAIN ISSUE WILL BE THE POTENTIAL FOR SEVERE. STILL THINK THE BEST POTENTIAL FOR SEVERE WILL BE THE EXTREME SOUTHEAST PORTION OF THE CWFA. HOWEVER...ANOTHER THING TO CONSIDER WILL BE THE MOVEMENT OF THE ACTIVITY ACROSS EASTERN MS/WESTERN AL. IF THE MCS CONTINUES TO SHIFT TO THE SE...THIS COULD HELP LIMIT THE DEVELOPMENT OF WIDESPREAD CONVECTION ACROSS THE CWFA. NEWEST RUNS OF THE HRRR DO TAKE THE STRONGEST ACTIVITY ACROSS SOUTHERN GA AND THE FLORIDA PANHANDLE DURING THE MORNING HOURS. THIS WOULD MEAN THAT A FEW STRONG/ISOLATED SEVERE STORMS...ARE POSSIBLE ACROSS THE EXTREME SOUTHERN PART OF THE CWFA. IN ADDITION...BEHIND THE INITIAL MCS BUT STILL AHEAD OF THE COLD FRONT...THE HRRR HAS SCATTERED THUNDERSTORMS BREAKING OUT ACROSS THE SE...SO THE POTENTIAL FOR STRONG STORMS/ISOLD SEVERE MAY LAST INTO THE MID TO LATE AFTERNOON HOURS...WHEN THERE IS MORE POTENTIAL FOR BREAKS IN THE CLOUDS AND FOR SURFACE DESTABILIZATION TO OCCUR. LUCKILY...SHEAR VALUES ARE RATHER WEAK...WITH THE BEST VALUES ALONG THE LAGGING COLD FRONT THIS EVENING. IF SEVERE THUNDERSTORMS ARE ABLE TO DEVELOP...DAMAGING WIND GUSTS AND LARGE HAIL WOULD BE THE PRIMARY THREATS. THE HRRR DOES CLEAR OUT THE POPS A BIT FASTER THAN PREVIOUSLY FORECAST. HAVE TRIED TO ACCOUNT FOR THIS IN TIMING. TEMPS IN THE NE WILL DIP DOWN INTO THE MIDDLE 30S TONIGHT...BUT LUCKILY...THE FORECAST SHOULD BE DRY. TOO MARGINAL TO ISSUE A FREEZE WATCH...AND THE WINDS MAY STAY UP OVERNIGHT JUST ENOUGH TO LIMIT FROST DEVELOPMENT. NLISTEMAA .LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/... HIGH PRESSURE DOMINATES FOR THE BEGINNING OF THE EXTENDED. A WEAK FRONT APPROACHES THE AREA ON TUESDAY BUT THE PRECIPITATION ASSOCIATED WITH IT SHOULD DIMINISH BEFORE REACHING THE STATE. SYSTEM OF INTEREST IN THE EXTENDED THOUGH IS NEAR THE END. BOTH THE ECMWF AND THE GFS LIFT A SFC LOW OUT OF THE MIDWEST AND INTO THE OHIO VALLEY/GREAT LAKES REGION ON FRIDAY AND PUSHES SHOWERS AND THUNDERSTORMS ACROSS THE CWA AHEAD OF A COLD FRONT THATS PROGGED TO MOVE THROUGH FRIDAY NIGHT. STILL SOME DIFFERENCES BETWEEN THE TWO MODELS IN TERMS OF FEATURE LOCATIONS...BUT OVERALL BOTH SUGGEST A GOOD CHANCE OF SHOWERS AND THUNDERSTORMS LATE IN THE WEEK. WILL HAVE TO CAREFULLY MONITOR FRIDAY FOR SEVERE WEATHER POTENTIAL AS THE GFS INDICATES UP TO 2000 J/KG OF MUCAPE ON FRIDAY WITH 30-40KTS OF LOW LEVEL SHEAR. 11 && .AVIATION... 06Z UPDATE... COLD FRONT WILL MOVE THROUGH THE REGION TODAY. CURRENTLY...LIGHT SHOWERS AND SPRINKLES SHOWING UP ON THE REGIONAL RADAR WHILE THE STRONG THUNDERSTORMS ARE BACK OVER EASTERN MS. HRRR PROGS THE THUNDERSTORMS TO BEGIN APPROACHING THE AL/GA BORDER AROUND 10Z AND PROGRESSING EASTWARD THROUGH THE MORNING. WINDS ARE EXPECTED. WINDS WILL TURN MORE WESTERLY BEHIND THE LINE OF STORMS...AND THEN BACK TO THE NW LATER THIS EVENING BEHIND THE COLD FRONT. WINDS BEHIND THE LINE WILL BE GUSTY. //ATL CONFIDENCE...06Z UPDATE... MEDIUM CONFIDENCE ALL ELEMENTS. && .PRELIMINARY POINT TEMPS/POPS... ATHENS 66 39 66 37 / 100 20 0 0 ATLANTA 65 39 64 42 / 100 10 0 0 BLAIRSVILLE 59 33 57 32 / 100 30 0 0 CARTERSVILLE 62 37 64 34 / 90 10 0 0 COLUMBUS 69 42 68 42 / 100 10 0 0 GAINESVILLE 63 38 64 40 / 100 20 0 0 MACON 70 42 67 37 / 100 10 0 0 ROME 62 37 65 34 / 80 10 0 0 PEACHTREE CITY 66 38 65 34 / 100 10 0 0 VIDALIA 72 45 69 41 / 80 30 0 0 && .FFC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...NLISTEMAA LONG TERM....11 AVIATION...NLISTEMAA
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
309 AM EDT SAT MAR 29 2014 .SYNOPSIS... MOISTURE WILL BE HIGH AHEAD OF A COLD FRONT. THE FRONT WILL MOVE THROUGH THE FORECAST AREA THIS EVENING. HIGH PRESSURE AND DRY CONDITIONS WILL PREVAIL SUNDAY AND MONDAY. && .NEAR TERM /THROUGH TONIGHT/... ISENTROPIC LIFT WILL SUPPORT NUMEROUS SHOWERS EARLY THIS MORNING. THE MESOSCALE CONVECTIVE COMPLEX APPROACHING THE FORECAST AREA FROM THE WEST SHOULD REACH THE AREA LATE THIS MORNING. RADAR TRENDS AND THE LATEST HRRR INDICATE THE STRONGER CONVECTION WILL REMAIN SOUTH OF THE AREA. STRONGER CONVERGENCE AHEAD OF THE COLD FRONT SHOULD BEGIN TO ENTER THE FORECAST AREA FROM THE WEST AROUND THE MIDDLE OF THE AFTERNOON. SHEAR WILL BE HIGH WITH H85 WINDS OF 30 TO 40 KNOTS SUPPORTING POSSIBLE SEVERE THUNDERSTORMS. THE THREAT APPEARS LIMITED BECAUSE IT IS QUESTIONABLE HOW MUCH MOISTURE AND INSTABILITY RECOVERY WILL OCCUR IN THE WAKE OF THE LARGE COMPLEX THIS MORNING. THE THREAT OF THUNDERSTORMS WILL CONTINUE INTO THE EVENING WITH THE COLD FRONT IN THE AREA AND COOLING ALOFT ASSOCIATED WITH THE UPPER-LEVEL TROUGH. DRYING SHOULD OCCUR LATER IN THE EVENING BEHIND THE COLD FRONT. USED THE GUIDANCE CONSENSUS FOR THE TEMPERATURE FORECAST. && .SHORT TERM /SUNDAY THROUGH SUNDAY NIGHT/... HIGH PRESSURE WILL BUILD OVER THE AREA SUNDAY THROUGH SUNDAY NIGHT. IT WILL BE BREEZY SUNDAY AND A LAKE WIND ADVISORY WILL LIKELY BE NEEDED. THE GFS AND NAM MOS SUPPORT WINDS OF 15 TO 25 KNOTS. WINDS SHOULD DIMINISH SUNDAY NIGHT AS THE HIGH GETS CLOSER TO THE AREA AND THE PRESSURE GRADIENT WEAKENS. STRONG NET RADIATIONAL COOLING CONDITIONS SHOULD DEVELOP LATE. USED THE GUIDANCE CONSENSUS FOR THE TEMPERATURE FORECAST. EXPECT LOWS IN THE MID AND UPPER 30S SUNDAY NIGHT WITH SCATTERED FROST. A FROST ADVISORY MAY BE NEEDED. && .LONG TERM /MONDAY THROUGH FRIDAY/... THE GFS AND ECMWF INDICATE DRY HIGH PRESSURE SHOULD DOMINATE DURING MUCH OF THE PERIOD. MOISTURE SHOULD BE ON THE INCREASE LATE IN THE PERIOD AHEAD OF A COLD FRONT. WARMER TEMPERATURES SHOULD OCCUR AS THE HIGH SHIFTS EASTWARD AND THE AIR MASS CONTINUES TO MODIFY. THE GFS...ECMWF... AND EKD MOS SUPPORT HIGHS IN THE UPPER 70S TO AROUND 80. && .AVIATION /07Z SATURDAY THROUGH WEDNESDAY/... SHOWERS ACROSS THE MIDLANDS SLOWLY MOVING EAST AS AN UPPER LEVEL DISTURBANCE CROSSES THE AREA. WILL ABUNDANT LOW-LEVEL MOISTURE...EXPECT IFR/POSSIBLE LIFR CIGS PERSISTING THROUGHOUT THE EARLY MORNING HOURS. COULD SEE SCATTERED SHOWERS OR PATCHY DRIZZLE CONTINUING DURING THE EARLY MORNING HOURS. MVFR CONDITIONS EXPECTED TO RETURN AROUND 16Z SATURDAY AS SOUTHERLY WINDS INCREASE AHEAD OF THE APPROACHING COLD FRONT. THERE SHOULD BE AN AREA SHOWERS/TSTMS TO CROSS THE TAF SITES DURING THE AFTERNOON AHEAD OF THE COLD FRONT. THE COLD FRONT WILL CROSS THE TAF SITES AROUND THE END OF THE TAF PERIOD. EXTENDED AVIATION OUTLOOK...BREEZY CONDITIONS AREA EXPECTED IN THE WAKE OF THE FRONT SATURDAY NIGHT INTO SUNDAY. && .CAE WATCHES/WARNINGS/ADVISORIES... SC...NONE. GA...NONE. && $$
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
150 AM EDT SAT MAR 29 2014 .PREV DISCUSSION... /ISSUED 1022 PM EDT FRI MAR 28 2014/ UPDATE...HAS BEEN QUITE AN INTERESTING NIGHT AS INITIAL THOUGHTS WERE THAT GULF COAST CONVECTION HAD SAVED US ONCE AGAIN AND WE WOULD ONLY SEE A LIGHT RAIN SHIELD MOVE IN WITH LITTLE FANFARE. AND FOR ALL OUTWARD APPEARANCES THAT IS WHAT HAPPENED...THAT IS UNTIL A WAKE LOW FORMED OVER ALABAMA AND PROGRESSED EAST ALLOWING FOR 4MB PRESSURE FALLS IN THE 2 HOUR PLOT. ALTHOUGH NOT WIDESPREAD BY ANY MEANS...THIS RESULTED IN ISOLATED POCKETS OF WIND GUSTS IN EXCESS OF 40 MPH AND LINED UP VERY WELL WITH 4MB BULLSEYE AS IT TRACKED ACROSS THE FORECAST AREA. DAMAGE REPORTS FROM HOUSTON COUNTY INCLUDED TREES DOWN INCLUDING SOME IN HOMES. IN LATEST RADAR PICS...YOU CAN NOW SEE THE MESOVORTICE IN THE REFLECTIVITY PATTERN AS IT EXITS THE FORECAST AREA. FOR THE REMAINDER OF THE FORECAST...CONVECTION OVER NORTHERN ARKANSAS WHICH RACED OUT AHEAD HAS BEEN IN THE MORE STABLE SECTOR AND ELEVATED IN NATURE. REGIONAL CAPE ANALYSIS SHOWS ALL SURFACE BASED CAPE TO BE SOUTH ACROSS MISSISSIPPI AND ALABAMA WITH NON NOTED TO THE EAST AT THIS TIME INCLUDING GEORGIA. EXPECT A SIMILAR SCENARIO TO TODAY WITH SOUTHERN ACTIVITY TAKING OVER AND DIVING SE AS IT LOOKS FOR THE MORE ENRICHED AIR ALONG THE GULF COAST. NORTHERN ACTIVITY WHICH WILL AFFECT US WILL STILL BE CAPABLE OF PRODUCING THUNDERSTORMS AND ISOLATED STRONG GUSTS BUT GREATEST POTENTIAL FOR SEVERE WILL REMAIN SOUTH OF THE AREA. SHERB PLOT CONFIRMS THIS TAKING THE 1 UNIT VALUES SOUTH OF THE AREA BUT PLENTY OF HIGH END 9 VALUES TO KEEP AN EYE ON OUR ZONES ALONG AND SOUTH OF A COLUMBUS TO MACON LINE. CLEANED UP POPS AND ADJUSTED TIMING A BIT IN GRIDS. OTHERWISE NO OTHER CHANGES PLANNED. DEESE PREV DISCUSSION... /ISSUED 736 PM EDT FRI MAR 28 2014/ PREV DISCUSSION... /ISSUED 343 PM EDT FRI MAR 28 2014/ SHORT TERM /TONIGHT THROUGH SATURDAY NIGHT/... MODELS HAVE HAD A POOR HANDLE ON THE CURRENT SITUATION...AND OVERALL FORECAST CONFIDENCE IS MEDIUM. LARGE AREA OF RAINFALL ACROSS THE AREA TODAY HAS BEEN FURTHER SOUTH THAN PREVIOUS MODELS AND FORECAST HAD INDICATED. LARGE COMPLEX OVER THE NORTHERN GULF HAS CUT OFF THE MOISTURE INFLUX INTO THE AREA AND PREVENTED THE CWA FROM SEEING ANY SIGNIFICANT CONVECTION. AS OF THIS AFTERNOON...RAINFALL AMOUNTS ACROSS THE AREA WERE HIGHEST ALONG THE AL/GA LINE...WITH 1.5 INCHES...AND DIMINISHED EASTWARD WITH ONLY 0.25 INCHES IN THE EASTERN PORTIONS OF THE STATE. MODELS ARE SUGGESTING A BREAK IN THE PRECIP THIS EVENING INTO THE OVERNIGHT HOURS BEFORE THE NEXT WAVE OF PRECIPITATION ASSOCIATED WITH THE FRONT AS IT PUSHES THROUGH THE AREA. LATEST MODEL RUNS DO NOT DEPICT MUCH IN THE WAY OF ORGANIZED CONVECTION EARLY MORNING AND THROUGH THE DAY SATURDAY...WITH A SIMILAR SITUATION AS TODAY WITH A COMPLEX OVER THE NORTHERN GULF RESTRICTING THE CWAS CHANCE OF THUNDERSTORMS. THAT BEING SAID...A FEW MODELS /LARGELY THE GFS/ IS CONTINUING TO SHOW CAPE VALUES IN THE 1200-1400 J/KG ACROSS THE FAR SOUTHERN AND EASTERN PORTIONS OF THE CWA SATURDAY LATE MORNING THROUGH THE AFTERNOON. OTHER MODELS HAVE 200-500 J/KG. ALTHOUGH THE INITIAL THINKING WAS THAT THIS PORTION OF THE CWA WOULD HAVE MORE OPPORTUNITY FOR HEATING SATURDAY WITH LESS CLOUD COVER...MODELS HAVE INCREASED MOISTURE TO THAT AREA...AND DO NOT ANTICIPATE MUCH INSOLATION. OVERALL THE BEST SHEAR DOES NOT COINCIDE WITH THE BEST MODELED INSTABILITY...ASSOCIATED MORE WITH THE FRONT ITSELF. AS A RESULT...HAVE CAPPED MENTION OF THUNDER TO CHANCE FOR SATURDAY. THE POTENTIAL FOR STRONG STORMS STILL EXISTS...AND THOUGH THE RISK OF SEVERE STORMS HAS DIMINISHED SOMEWHAT IN THE MODELS...ISOLATED SEVERE STORMS MAY STILL BE POSSIBLE IN THE SE PORTION OF THE CWA. THE MAIN CONCERN WOULD BE DAMAGING WINDS. ADDITIONAL WIDESPREAD RAINFALL AMOUNTS OF 1.0 INCHES WITH LOCALLY HIGHER AMOUNTS CAN BE EXPECTED THROUGH SATURDAY AFTERNOON. AT THIS TIME THE AREA HAS BEEN ABLE TO HANDLE THE RAINFALL WELL...AND DO NOT ANTICIPATE WIDESPREAD FLOODING CONCERNS. THE RAIN EXITS THE STATE LATE SATURDAY AFTERNOON WITH CLEARING QUICKLY BEHIND IT. WITH GRADIENT WINDS INCREASING SATURDAY AFTERNOON...THERE IS A POSSIBILITY OF MEETING WIND ADVISORY CRITERIA IN THE HIGHER ELEVATIONS OF NORTH GEORGIA. WILL ALLOW THE NEXT SHIFTS TO REEVALUATE THE NEED FOR A WIND ADVISORY AND WILL HOLD OFF FOR NOW. 31 LONG TERM /SUNDAY THROUGH FRIDAY/... MADE SOME ADJUSTMENTS TO LOWER POPS AND THUNDERSTORM POTENTIAL THURSDAY THEN INCREASE POTENTIAL FOR FRIDAY BASED ON LATEST MODEL SOLUTIONS. WILL HAVE TO WATCH TRENDS WITH POSSIBLE STRONG FRONT MOVING THROUGH AREA FRIDAY /GIVEN 12Z RUN OF GFS/ AND ANY POTENTIAL FOR STRONGER STORM DEVELOPMENT ASSOCIATED WITH IT. MUCH COULD HAPPEN THIS LATE IN THE FORECAST. ALSO...ANY POTENTIAL FOR LIGHT SNOW SATURDAY NIGHT LOOKS TO BE OUTSIDE OF THE CWA. OTHERWISE FORECAST LOOKS TO BE ON TRACK AND PREVIOUS DISCUSSION FOLLOWS... BAKER PREV DISCUSSION... /ISSUED 341 AM EDT FRI MAR 28 2014/ LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/... FOR THE MOST PART...SYSTEM THAT BRINGS RAIN TO THE AREA IN THE SHORT TERM SHOULD HAVE EXITED THE AREA BY THE BEGINNING OF THE LONG TERM. THE EXCEPTION TO THIS IS ACROSS FAR NORTHEAST GEORGIA AND THE FAR SOUTHEAST PART OF THE CWA WHERE SOME RAIN COULD LINGER THROUGH SATURDAY NIGHT. AT THIS POINT...IT APPEARS THE PRECIPITATION SHOULD END ACROSS THE NE GA MOUNTAINS BEFORE THE COOLER TEMPERATURES MOVE IN. AFTER THIS HIGH PRESSURE WILL DOMINATE THROUGH ABOUT MID WEEK. BOTH THE GFS AND THE ECMWF SUGGEST THE NEXT SYSTEM MOVING THROUGH IN THE LATER HALF OF THE WEEK. INSTABILITY VALUES SUPPORT THE MENTION OF THUNDER IN THE FORECAST THURSDAY INTO FRIDAY. 11 && .AVIATION... 06Z UPDATE... COLD FRONT WILL MOVE THROUGH THE REGION TODAY. CURRENTLY...LIGHT SHOWERS AND SPRINKLES SHOWING UP ON THE REGIONAL RADAR WHILE THE STRONG THUNDERSTORMS ARE BACK OVER EASTERN MS. HRRR PROGS THE THUNDERSTORMS TO BEGIN APPROACHING THE AL/GA BORDER AROUND 10Z AND PROGRESSING EASTWARD THROUGH THE MORNING. WINDS ARE EXPECTED. WINDS WILL TURN MORE WESTERLY BEHIND THE LINE OF STORMS...AND THEN BACK TO THE NW LATER THIS EVENING BEHIND THE COLD FRONT. WINDS BEHIND THE LINE WILL BE GUSTY. //ATL CONFIDENCE...06Z UPDATE... MEDIUM CONFIDENCE ALL ELEMENTS. && .PRELIMINARY POINT TEMPS/POPS... ATHENS 72 42 69 38 / 70 20 0 0 ATLANTA 69 42 65 42 / 90 10 0 0 BLAIRSVILLE 65 37 62 34 / 70 30 0 0 CARTERSVILLE 69 41 65 36 / 80 10 0 0 COLUMBUS 73 47 70 42 / 100 10 0 0 GAINESVILLE 68 41 64 40 / 80 20 0 0 MACON 74 44 71 38 / 100 10 0 0 ROME 68 42 66 35 / 80 10 0 0 PEACHTREE CITY 71 41 67 35 / 100 10 0 0 VIDALIA 75 48 71 43 / 90 30 0 0 && .FFC WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
252 PM CDT SAT MAR 29 2014 .DISCUSSION... 302 AM CDT TODAY... THIS MORNING...RIDGE OF HIGH PRESSURE EXTENDS FROM LAKE SUPERIOR INTO THE MID MISSOURI VALLEY WHILE LOW PRESSURE LIES OVER MISSISSIPPI/ALABAMA. THIS LOW WILL LIFT NORTH INTO THE UPPER OHIO VALLEY TODAY RESULTING IN NORTHEASTERLY WINDS OFF OF LAKE MICHIGAN THROUGH THE DAY. SOME PRECIP MAY BRUSH THE FAR SOUTHEASTERN COUNTIES THIS MORNING...MAINLY IN THE FORM OF SNOW...THOUGH ANY ACCUMULATION WILL LIKELY BE CONFINED TO GRASSY AREAS AND ONLY A DUSTING IS EXPECTED. SPLIT CHANNEL IR IMAGERY SHOWS STRATUS STILL SPANS MUCH OF THE UPPER MIDWEST...AS FAR WEST AS CENTRAL IOWA AND NORTHWEST INTO CENTRAL WISCONSIN. EXPECT CLOUD COVER TO LINGER THROUGH AT LEAST MIDDAY...THEN ANTICYCLONIC FLOW WITH THE RIDGE AXIS SHOULD START TO BUILD IN FROM THE NORTHWEST THIS AFTERNOON AND EVENING WITH SKIES CLEARING. TEMPERATURES TODAY ARE EXPECTED TO WARM INTO THE LOW TO MID 40S...THOUGH WILL STAY IN THE 30S NEAR THE LAKE WITH THE OFFSHORE FLOW THROUGH THE DAY. SUNDAY AND MONDAY... COMPACT UPPER WAVE WILL MOVE ONSHORE OVER SOCAL EARLY SUNDAY...THEN TRANSLATE EAST ACROSS THE CENTRAL PLAINS BY MONDAY. SURFACE LOW WILL DEEPEN IN RESPONSE OVER THE CENTRAL PLAINS THROUGH THE PERIOD WITH STRONG WARM ADVECTION INTO THE REGION HELPING TO AMPLIFY THE MID/UPPER LEVEL RIDGING. H85 TEMPS WILL WARM TO AROUND 10C BY SUNDAY EVENING...AND 12C TO 13C BY MONDAY. CLIMO FROM NARR DATASET SHOWS MEDIAN TEMPS IN THE LOW 70S WHEN H85 TEMPS EXCEED AROUND 9C FOR THE LATTER HALF OF MARCH. WHILE THESE WARMER TEMPERATURES ALOFT WILL ARRIVE LATER IN THE DAY SUNDAY...THEY SHOULD BE DIRECTLY OVERHEAD ON MONDAY WHICH IS EXPECTED TO BE THE WARMEST DAY IN SOME TIME. BACKED OFF SLIGHTLY ON TEMPS FOR SUNDAY...AND WHILE I THINK AREAS ESPECIALLY IN THE WESTERN CWA STILL HAVE A GOOD CHANCE OF 60...IT MAY STRUGGLE TO REACH 60 IN CHICAGO AND EASTERN PORTIONS OF THE CWA DUE TO THE SLOWER ARRIVAL. THE MAIN CONCERNS FOR TEMPS MONDAY REVOLVE AROUND CONVECTIVE CHANCES AND CLOUD COVER WHICH WILL INHIBIT HOW WARM WE GET. H5 VORT TAKES ON A NEGATIVE TILT MONDAY AS IT LIFTS ACROSS THE MID-MISSOURI VALLEY AND LEFT EXIT REGION OF UPPER JET OVER THE AREA WILL PROVIDE ADDITIONAL BROAD SCALE ASCENT. LATEST THINKING ON TIMING OF THE LOW STILL HAS THE BETTER FORCING WELL TO THE WEST DURING PEAK HEATING WHEN SOME VERY MODEST SURFACE BASED INSTABILITY EXISTS. WITH THUNDERSTORMS DEVELOPING TO THE WEST...COULD SEE CIRRUS STREAMING OVERHEAD DURING THE DAY MONDAY WHICH WILL IMPACT TEMPS. WITH A PRETTY DYNAMIC SYSTEM...MAY BE ABLE TO OVERCOME THE LACK OF FAVORABLE THERMODYNAMICS FOR SOME SCATTERED SHOWERS AND THUNDERSTORMS TO DEVELOP...PARTICULARLY IN THE LATER AFTERNOON AND EVENING. REFINED POPS TO REFLECT THESE TIMING DETAILS BUT MAINTAINED 20 TO 30 PERCENT DUE TO COVERAGE CONCERNS. AS FAR AS TEMPS...REMAIN ON THE WARM SIDE OF THE SOLUTION ENVELOPE BUT WILL HOLD OFF ON GOING ABOVE GUIDANCE GIVEN THE EXPECTED CLOUD COVER AND UNCERTAINTY IN PRECIP. WINDS WILL BECOME PROGRESSIVELY BREEZY THROUGH THIS PERIOD...WITH GUSTS TO AROUND 20 MPH POSSIBLE ON SUNDAY AND EVEN BREEZIER CONDITIONS ON MONDAY. 50KT WINDS ARE NOTED AROUND 900MB MONDAY...AND WITH DEEP MIXING POSSIBLE...THE AREA MAY SEE 30MPH+ GUSTS AT THE SURFACE DURING THE AFTERNOON. TUESDAY THROUGH FRIDAY... AN ACTIVE PATTERN IS EXPECTED TO CONTINUE THROUGH THE REMAINDER OF THE UPCOMING WORK WEEK AS A SERIES OF WAVES PROGRESS ACROSS THE REGION. STILL CONSIDERABLE TIMING/TRACK DIFFERENCES THOUGH GUIDANCE DOES SEEM TO BE FAVORING A MORE SOUTHERLY/COOLER PATTERN... ESPECIALLY THE GFS WITH GOOD SUPPORT FROM THE GEFS. THE EMCWF MAINTAINS A WARMER SOLUTION...WITH BAROCLINIC ZONE VERY NEAR RESULTING IN A DECENT TEMPS SPREAD NORTH TO SOUTH ACROSS THE CWA. CONTINUE TO RUN WITH A MODEL CONSENSUS BLEND FOR TEMPS NEXT WEEK GIVEN THE HIGH DEGREE OF UNCERTAINTY...WHICH RESULTS IN WELL BELOW NORMAL TEMPS. DEUBELBEISS && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 18Z... * MVFR CIGS SCATTERING/CLEARING TOWARD 21Z. * NORTHEAST WINDS THROUGH THE EVENING. MDB //DISCUSSION...UPDATED 18Z... MVFR STRATUS CONTINUES TO PUSH SOUTHWARD ACROSS THE CHICAGO AREA TERMINALS WITH A CORRIDOR OF IFR CIGS AND MIST/DRIZZLE DOWN NEAR GYY. THE IFR SHOULD IMPROVE AT GYY IN THE NEXT HOUR OR SO WHILE ORD/MDW/DPA SEE STEADILY IMPROVING CLOUD BASES THEN SCATTERING OF COVERAGE THROUGH EARLY AFTERNOON. OTHERWISE NORTHEASTERLY WINDS WILL CONTINUE THROUGH THE EVENING WITH SPEEDS DIMINISHING INTO THE OVERNIGHT HOURS. LIGHT AND VARIABLE WINDS FAVORING AN EAST THEN SOUTHEAST DIRECTION ARE EXPECTED SUNDAY MORNING WITH STEADIER SOUTH WINDS SPREADING IN FROM WEST TO EAST AS HIGH PRESSURE CROSSES THE AREA. WITH THE HIGH OVERHEAD OVERNIGHT MAY SEE SOME PATCHY FOG AT DPA...AND POSSIBLY RFD FOR A FEW HOURS THROUGH DAYBREAK. WILL NOT INDICATE ANY RESTRICTIONS IN THESE TAFS FOR NOW AS THE SETUP LOOKS A BIT MARGINAL. MDB //ORD AND MDW CONFIDENCE...UPDATED 18Z... * HIGH CONFIDENCE IN MVFR CIGS SCATTERING/CLEARING...MEDIUM CONFIDENCE IN TIMING. * HIGH CONFIDENCE IN WIND FORECAST. MDB //OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z... SUNDAY NIGHT...VFR. MONDAY...CHANCE OF TSRA. GUSTY SOUTH WINDS. TUESDAY...SLGT CHC OF RAIN DURING THE NIGHT. WEDNESDAY...RAIN AND MVFR LIKELY. THURSDAY AND FRIDAY...SLGT CHC OF RAIN AND SNOW. LENNING && .MARINE... 251 PM CDT NORTH-NORTHEASTERLY ONSHORE FLOW ACROSS NORTHEASTERN ILLINOIS AND NORTHWESTERN INDIANA CONTINUES UP AROUND 20S OUT AHEAD OF AN AREA OF HIGH PRESSURE. THIS FLOW IS BIT STRONGER THAN PREVIOUSLY THOUGH...AND AS A CONSEQUENCE OF THIS...I HAVE ISSUED A SMALL CRAFT ADVISORY THROUGH THIS EVENING...MAINLY FOR THE EXPECTATION THAT WAVES ARE AT OR JUST ABOVE THE 4 FOOT MARK. THESE WINDS WILL ABATE THIS EVENING...THEN GRADUALLY BECOME EAST-SOUTHEASTERLY OVERNIGHT TONIGHT AS THE SURFACE RIDGE SHIFTS OVER THE LAKE. LOW PRESSURE WILL BE IN THE PROCESS OF DEVELOPING ACROSS THE CENTRAL HIGH PLAINS ON SUNDAY...AND THIS WILL RESULT IN A CONTINUAL SOUTH-SOUTHEASTERLY FLOW PATTERN ACROSS THE LAKE FOR THE NEXT COUPLE OF DAYS. THE LOW IS EXPECTED TO TRACK EAST-NORTHEASTERLY TO THE UPPER MISSISSIPPI VALLEY BY LATE MONDAY EVENING...THEN SHIFT ACROSS THE UPPER GREAT LAKES BY TUESDAY EVENING. OVERALL...THIS WILL RESULT IN INCREASING SOUTHERLY WINDS MONDAY AND INTO MONDAY EVENING...LIKELY TO AROUND 30 KT. OVERALL...IT APPEARS THAT WARMER AIR MOVING OVER THE LAKE WILL RESULT IN A STABLE MARINE LAYER...WHICH WOULD RESULT IN LOWER CHANCES FOR GALES. HOWEVER...SOME STRONGER WINDS NEARLY GALE FORCE ARE POSSIBLE WITH THIS SYSTEM...ESPECIALLY MONDAY NIGHT AS THE LOW AND COLD FRONT APPROACH THE LAKE. WESTERLY FLOW WILL SET UP TUESDAY IN THE WAKE OF THIS SYSTEM. ANOTHER STORM SYSTEM LOOKS TO TAKE AIM ON THE LOWER GREAT LAKES LATER IN THE PERIOD...AROUND THURSDAY. THIS COULD RESULT IN A PERIOD OF SOME ENHANCED NORTHEASTERLY WINDS INTO THE END OF THE UP COMING WEEK. KJB && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS UNTIL 10 PM SATURDAY. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion National Weather Service Lincoln IL 228 PM CDT Sat Mar 29 2014 .DISCUSSION... ISSUED 228 PM CDT Sat Mar 29 2014 The progressive weather pattern will provide active weather next week as several storm systems affect Illinois. The latter half of this weekend looks pleasant with plenty of sunshine pushing temps above normal. However, by Monday afternoon the first system will bring chances of rain, and the onset of a return to cooler conditions. Heavier rains in the Wed to Thur time frame could accumulate between 1-2" in some locations. Localized flooding may develop. SHORT TERM...Tonight through Sunday night. Low clouds have been keeping high temps generally below forecast highs this afternoon. A narrow break in the cloud cover allowed Peoria to spike up about 10 degrees in a couple hours, and create a large temperature gradient over short distances in our forecast area. The RAP and HRRR layer RH indicate that some clearing should continue west of I-57 between 23z and 03z. Lows tonight will be dependent on cloud cover. Areas east of I-57 may remain cloudy until just after midnight as NE surface winds continue to drag low- level moisture from the Great Lakes into eastern IL. Even a few hours of clearing later tonight should allow eastern areas to cool off to near guidance lows, especially with surface dewpoints dipping into the upper 20s in many locations. Sunday will see mid level temps climb 5 to 7C during the day as an upper level ridge axis advances into eastern IL by 00z/7pm Monday. Near full sunshine should combine with increasing south winds to push highs about 10 to 15 deg above normal (60s), which will be a welcome taste of Spring. An tightening pressure gradient ahead of the next system will keep south winds up in the 10 to 20 mph range even Sunday night. So despite clear skies Sunday night, south winds will keep a mixed boundary layer and allow lows to be in the upper 40s west and around 40 east. LONG TERM...Monday through Saturday. Increasing clouds on Monday will not prohibit highs from climbing well into the 60s for one more day, as south-southeast winds increase into the 25 to 35 mph range. By Monday afternoon, a parent low pressure system will advance from eastern Nebraska to southeastern Minn, as a cold front reaches the western border of IL by 00z/7pm Monday. Pre-frontal storms will have a high amount of wind shear and storm relative helicity available, along with steep lapse rates, but a limited amount of moisture. Forecast soundings show the best instability may be at or above 750 mb, so any thunderstorms will be elevated to begin. Due the strong jet dynamics and wind shear with this system, some of the storms could begin rotating and produce hail and strong winds Monday afternoon and evening ahead of the cold front. Showers and storms should end from west to east by midnight in the post-frontal subsidence and dry air intrusion. Clouds will likely clear out behind the line of precip, so lows in the NW could dip below freezing, while southeast areas remain in the low 40s. The brief pocket of cold air is forecast to brush across N IL late Mon night and Tues morning, which will keep highs about 10-15 deg colder than Monday. High temps will range from around 50 near Galesburg to around 60 by Lawrenceville. Return flow behind the cooler high pressure will bring increasing moisture Tuesday night, with a few showers possible before sunrise on Wednesday. Thunderstorm chances will increase along and south of a warm front that is expected to develop directly across central IL from west to east. Storm chances will be higher in the warm sector roughly south of a line from Rushville to Champaign. Instability may have a better chance of being based closer to the surface as dewpoints climb into the 50s Wed night south of the warm front, which will be close to overnight low temps. Precipitable water values are expected to climb over an inch Wed night through Thursday as low pressure tracks northeast along the warm front. Locally heavy rain may occur in any thunderstorms, with training of storms over the same area also boosting rainfall amounts. Localized flooding could develop in low areas, as rainfall amounts possibly reach between 1 and 2 inches by Thursday afternoon. A wide range of temps will occur across C IL from north to south from Tues night through Thursday as the warm front lingers across the middle of the area. The temp spreads could be 20 to 25 degrees from north to south for highs and lows. There is a spread of solutions for how the surface and upper level systems progress from after Thursday. The GFS lingers the upper trough farther west Thurs night, then brings a secondary surface low and another round of rain showers across IL on Friday. The ECMWF is more progressive and drys out the air column after the low on Thursday. So low chance and slight chance PoPs were included Thurs night and Friday to account for a slower progression. There is some agreement that another push of cold air will keep temps below normal for Friday and Saturday, with Saturday looking dry at this time. Shimon && .AVIATION... ISSUED 1234 PM CDT Sat Mar 29 2014 MVFR stratus/SC will continue to affect terminals this afternoon. A thin clear slot separates a lower MVFR cloud mass likely augmented by Lake Michigan moisture, which has recently edged into BMI/CMI. Brief reductions to IFR cigs/vsbys likely especially towards CMI for the next few hours. Low level wind trajectories favor this region to sink more south than southwest this afternoon, staying east of PIA/SPI and possibly near DEC. Drier air associated with a surface ridge over IA will help scour out the cloud cover as it approaches the area late afternoon/early evening. 10-15 kt north winds will subside this evening, then go light/variable through sunrise as the ridge moves overhead. Return flow brings southeast winds near/under 10 kts by late morning along with scattered high clouds. 25 && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1256 PM CDT SAT MAR 29 2014 .DISCUSSION... 302 AM CDT TODAY... THIS MORNING...RIDGE OF HIGH PRESSURE EXTENDS FROM LAKE SUPERIOR INTO THE MID MISSOURI VALLEY WHILE LOW PRESSURE LIES OVER MISSISSIPPI/ALABAMA. THIS LOW WILL LIFT NORTH INTO THE UPPER OHIO VALLEY TODAY RESULTING IN NORTHEASTERLY WINDS OFF OF LAKE MICHIGAN THROUGH THE DAY. SOME PRECIP MAY BRUSH THE FAR SOUTHEASTERN COUNTIES THIS MORNING...MAINLY IN THE FORM OF SNOW...THOUGH ANY ACCUMULATION WILL LIKELY BE CONFINED TO GRASSY AREAS AND ONLY A DUSTING IS EXPECTED. SPLIT CHANNEL IR IMAGERY SHOWS STRATUS STILL SPANS MUCH OF THE UPPER MIDWEST...AS FAR WEST AS CENTRAL IOWA AND NORTHWEST INTO CENTRAL WISCONSIN. EXPECT CLOUD COVER TO LINGER THROUGH AT LEAST MIDDAY...THEN ANTICYCLONIC FLOW WITH THE RIDGE AXIS SHOULD START TO BUILD IN FROM THE NORTHWEST THIS AFTERNOON AND EVENING WITH SKIES CLEARING. TEMPERATURES TODAY ARE EXPECTED TO WARM INTO THE LOW TO MID 40S...THOUGH WILL STAY IN THE 30S NEAR THE LAKE WITH THE OFFSHORE FLOW THROUGH THE DAY. SUNDAY AND MONDAY... COMPACT UPPER WAVE WILL MOVE ONSHORE OVER SOCAL EARLY SUNDAY...THEN TRANSLATE EAST ACROSS THE CENTRAL PLAINS BY MONDAY. SURFACE LOW WILL DEEPEN IN RESPONSE OVER THE CENTRAL PLAINS THROUGH THE PERIOD WITH STRONG WARM ADVECTION INTO THE REGION HELPING TO AMPLIFY THE MID/UPPER LEVEL RIDGING. H85 TEMPS WILL WARM TO AROUND 10C BY SUNDAY EVENING...AND 12C TO 13C BY MONDAY. CLIMO FROM NARR DATASET SHOWS MEDIAN TEMPS IN THE LOW 70S WHEN H85 TEMPS EXCEED AROUND 9C FOR THE LATTER HALF OF MARCH. WHILE THESE WARMER TEMPERATURES ALOFT WILL ARRIVE LATER IN THE DAY SUNDAY...THEY SHOULD BE DIRECTLY OVERHEAD ON MONDAY WHICH IS EXPECTED TO BE THE WARMEST DAY IN SOME TIME. BACKED OFF SLIGHTLY ON TEMPS FOR SUNDAY...AND WHILE I THINK AREAS ESPECIALLY IN THE WESTERN CWA STILL HAVE A GOOD CHANCE OF 60...IT MAY STRUGGLE TO REACH 60 IN CHICAGO AND EASTERN PORTIONS OF THE CWA DUE TO THE SLOWER ARRIVAL. THE MAIN CONCERNS FOR TEMPS MONDAY REVOLVE AROUND CONVECTIVE CHANCES AND CLOUD COVER WHICH WILL INHIBIT HOW WARM WE GET. H5 VORT TAKES ON A NEGATIVE TILT MONDAY AS IT LIFTS ACROSS THE MID-MISSOURI VALLEY AND LEFT EXIT REGION OF UPPER JET OVER THE AREA WILL PROVIDE ADDITIONAL BROAD SCALE ASCENT. LATEST THINKING ON TIMING OF THE LOW STILL HAS THE BETTER FORCING WELL TO THE WEST DURING PEAK HEATING WHEN SOME VERY MODEST SURFACE BASED INSTABILITY EXISTS. WITH THUNDERSTORMS DEVELOPING TO THE WEST...COULD SEE CIRRUS STREAMING OVERHEAD DURING THE DAY MONDAY WHICH WILL IMPACT TEMPS. WITH A PRETTY DYNAMIC SYSTEM...MAY BE ABLE TO OVERCOME THE LACK OF FAVORABLE THERMODYNAMICS FOR SOME SCATTERED SHOWERS AND THUNDERSTORMS TO DEVELOP...PARTICULARLY IN THE LATER AFTERNOON AND EVENING. REFINED POPS TO REFLECT THESE TIMING DETAILS BUT MAINTAINED 20 TO 30 PERCENT DUE TO COVERAGE CONCERNS. AS FAR AS TEMPS...REMAIN ON THE WARM SIDE OF THE SOLUTION ENVELOPE BUT WILL HOLD OFF ON GOING ABOVE GUIDANCE GIVEN THE EXPECTED CLOUD COVER AND UNCERTAINTY IN PRECIP. WINDS WILL BECOME PROGRESSIVELY BREEZY THROUGH THIS PERIOD...WITH GUSTS TO AROUND 20 MPH POSSIBLE ON SUNDAY AND EVEN BREEZIER CONDITIONS ON MONDAY. 50KT WINDS ARE NOTED AROUND 900MB MONDAY...AND WITH DEEP MIXING POSSIBLE...THE AREA MAY SEE 30MPH+ GUSTS AT THE SURFACE DURING THE AFTERNOON. TUESDAY THROUGH FRIDAY... AN ACTIVE PATTERN IS EXPECTED TO CONTINUE THROUGH THE REMAINDER OF THE UPCOMING WORK WEEK AS A SERIES OF WAVES PROGRESS ACROSS THE REGION. STILL CONSIDERABLE TIMING/TRACK DIFFERENCES THOUGH GUIDANCE DOES SEEM TO BE FAVORING A MORE SOUTHERLY/COOLER PATTERN... ESPECIALLY THE GFS WITH GOOD SUPPORT FROM THE GEFS. THE EMCWF MAINTAINS A WARMER SOLUTION...WITH BAROCLINIC ZONE VERY NEAR RESULTING IN A DECENT TEMPS SPREAD NORTH TO SOUTH ACROSS THE CWA. CONTINUE TO RUN WITH A MODEL CONSENSUS BLEND FOR TEMPS NEXT WEEK GIVEN THE HIGH DEGREE OF UNCERTAINTY...WHICH RESULTS IN WELL BELOW NORMAL TEMPS. DEUBELBEISS && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 18Z... * MVFR CIGS SCATTERING/CLEARING TOWARD 21Z. * NORTHEAST WINDS THROUGH THE EVENING. MDB //DISCUSSION...UPDATED 18Z... MVFR STRATUS CONTINUES TO PUSH SOUTHWARD ACROSS THE CHICAGO AREA TERMINALS WITH A CORRIDOR OF IFR CIGS AND MIST/DRIZZLE DOWN NEAR GYY. THE IFR SHOULD IMPROVE AT GYY IN THE NEXT HOUR OR SO WHILE ORD/MDW/DPA SEE STEADILY IMPROVING CLOUD BASES THEN SCATTERING OF COVERAGE THROUGH EARLY AFTERNOON. OTHERWISE NORTHEASTERLY WINDS WILL CONTINUE THROUGH THE EVENING WITH SPEEDS DIMINISHING INTO THE OVERNIGHT HOURS. LIGHT AND VARIABLE WINDS FAVORING AN EAST THEN SOUTHEAST DIRECTION ARE EXPECTED SUNDAY MORNING WITH STEADIER SOUTH WINDS SPREADING IN FROM WEST TO EAST AS HIGH PRESSURE CROSSES THE AREA. WITH THE HIGH OVERHEAD OVERNIGHT MAY SEE SOME PATCHY FOG AT DPA...AND POSSIBLY RFD FOR A FEW HOURS THROUGH DAYBREAK. WILL NOT INDICATE ANY RESTRICTIONS IN THESE TAFS FOR NOW AS THE SETUP LOOKS A BIT MARGINAL. MDB //ORD AND MDW CONFIDENCE...UPDATED 18Z... * HIGH CONFIDENCE IN MVFR CIGS SCATTERING/CLEARING...MEDIUM CONFIDENCE IN TIMING. * HIGH CONFIDENCE IN WIND FORECAST. MDB //OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z... SUNDAY NIGHT...VFR. MONDAY...CHANCE OF TSRA. GUSTY SOUTH WINDS. TUESDAY...SLGT CHC OF RAIN DURING THE NIGHT. WEDNESDAY...RAIN AND MVFR LIKELY. THURSDAY AND FRIDAY...SLGT CHC OF RAIN AND SNOW. LENNING && .MARINE... 310 AM CDT WINDS GENERALLY WILL REMAIN NORTHERLY OR NORTHEASTERLY TODAY AHEAD OF AN APPROACHING HIGH PRESSURE RIDGE...THEN WILL VEER EAST AFTER THE RIDGE PASSES EARLY SUNDAY. THE EAST OR SOUTHEAST FLOW THEN PERSISTS THROUGH THE WEEKEND INTO EARLY NEXT WEEK. STRONG LOW PRESSURE MOVES THROUGH THE NORTHERN PART OF THE LAKE MONDAY NIGHT...LIKELY SUPPORTING A PERIOD OF GALES ON THE SOUTHERN HALF. THE WARM SOUTHERLY FLOW AHEAD OF THE LOW MONDAY AFTERNOON WILL BE VERY STRONG BUT MAY BE LESS EFFECTIVE AT CREATING GALES THAN THE WEAKER BUT COLDER WINDS BEHIND THE LOW ON MONDAY NIGHT AND TUESDAY. LENNING && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...NONE. && $$ 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 1234 PM CDT Sat Mar 29 2014 .DISCUSSION... ISSUED 1024 AM CDT Sat Mar 29 2014 Showers associated with low pressure in the eastern Tennessee Valley has now shifted east into Indiana and have updated forecast to reflect dry conditions across the entire CWA for the remainder of the day. Plenty of stratus continues to plague the region again today and main forecast issue is the potential for afternoon clearing and associated affect on high temps. A sliver of clearing is approaching the northern CWA but already starting to fill in with SC and a larger batch of stratus over NE IL is quickly advecting in behind this on NNE low level flow. Think clouds will hang tough as long as low level flow remains out of N/NNE which should last well into afternoon. As the low pulls further east winds will eventually come around to N/NNW advecting in drier air from NW IL and eastern IA, and subsidence off surface ridge to our west should help break up cloud deck. With this in mind have increased cloud cover through mid afternoon, lowered highs a degree or two, and slowed diurnal temp rise. && .AVIATION... ISSUED 1234 PM CDT Sat Mar 29 2014 MVFR stratus/SC will continue to affect terminals this afternoon. A thin clear slot separates a lower MVFR cloud mass likely augmented by Lake Michigan moisture, which has recently edged into BMI/CMI. Brief reductions to IFR cigs/vsbys likely especially towards CMI for the next few hours. Low level wind trajectories favor this region to sink more south than southwest this afternoon, staying east of PIA/SPI and possibly near DEC. Drier air associated with a surface ridge over IA will help scour out the cloud cover as it approaches the area late afternoon/early evening. 10-15 kt north winds will subside this evening, then go light/variable through sunrise as the ridge moves overhead. Return flow brings southeast winds near/under 10 kts by late morning along with scattered high clouds. 25 && .PREV DISCUSSION... ISSUED 227 AM CDT Sat Mar 29 2014 Surface low tracking across northern Mississippi early this morning, while an upper trough moves through Iowa and western Missouri. Area of showers streaming northward ahead of the upper trough has made it up to around Taylorville and Sullivan as of 2 am, although the leading edge has had to fight some dry air to make it that far. A rather active weather pattern is on tap for next week, with precipitation timing the primary forecast concern. SHORT TERM...Today through Monday: Will maintain some precipitation chances across the far eastern CWA for the first few hours after sunrise, until the trough moves into Illinois. Forecast soundings off the RAP model suggest some rain/snow mix north of I-70 until the ice crystals are lost by mid morning, with rain to the south. Otherwise, will see a decrease in clouds from west to east this afternoon, as ridge axis moves southeast out of the northern Plains. Decent warm air advection sets up early Sunday as the high drifts east of the state. With abundant sunshine, have sided more toward the MAV MOS highs in the lower to mid 60s, with temperatures in the mid to upper 60s on Monday. Monday looks to be fairly windy ahead of the next storm system, with Bufkit data suggesting wind gusts of 30-40 mph. Main surface low expected to track northeast into southern Minnesota by late afternoon, with the trailing cold front sweeping through the forecast area during the evening. Lower levels of the forecast soundings are rather dry though except for a brief window late afternoon and early evening, so will maintain PoP`s only in the 30 percent range. LONG TERM...Tuesday through Friday: Upper troughing begins to dig across California Tuesday night as a closed low moves southeast toward Los Angeles. As the week progresses, the question becomes how deep this remains and how fast the remaining closed low is ejected northeast. GFS and ECMWF maintain a rather wide range as a storm system develops over the Plains. The GFS remains much further south, with more of an inverted trough extending over southeast Illinois by Thursday morning. The ECMWF loiters a warm front just north of I-72 most of Wednesday and Thursday, before the parent low arrives Thursday evening. Both solutions would favor widespread showers, although the warmer ECMWF would suggest thunder being more widespread. Have not changed too much from the previous forecast, which favored the ECMWF and warmer temperatures. Geelhart && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1103 AM CDT SAT MAR 29 2014 .DISCUSSION... 302 AM CDT TODAY... THIS MORNING...RIDGE OF HIGH PRESSURE EXTENDS FROM LAKE SUPERIOR INTO THE MID MISSOURI VALLEY WHILE LOW PRESSURE LIES OVER MISSISSIPPI/ALABAMA. THIS LOW WILL LIFT NORTH INTO THE UPPER OHIO VALLEY TODAY RESULTING IN NORTHEASTERLY WINDS OFF OF LAKE MICHIGAN THROUGH THE DAY. SOME PRECIP MAY BRUSH THE FAR SOUTHEASTERN COUNTIES THIS MORNING...MAINLY IN THE FORM OF SNOW...THOUGH ANY ACCUMULATION WILL LIKELY BE CONFINED TO GRASSY AREAS AND ONLY A DUSTING IS EXPECTED. SPLIT CHANNEL IR IMAGERY SHOWS STRATUS STILL SPANS MUCH OF THE UPPER MIDWEST...AS FAR WEST AS CENTRAL IOWA AND NORTHWEST INTO CENTRAL WISCONSIN. EXPECT CLOUD COVER TO LINGER THROUGH AT LEAST MIDDAY...THEN ANTICYCLONIC FLOW WITH THE RIDGE AXIS SHOULD START TO BUILD IN FROM THE NORTHWEST THIS AFTERNOON AND EVENING WITH SKIES CLEARING. TEMPERATURES TODAY ARE EXPECTED TO WARM INTO THE LOW TO MID 40S...THOUGH WILL STAY IN THE 30S NEAR THE LAKE WITH THE OFFSHORE FLOW THROUGH THE DAY. SUNDAY AND MONDAY... COMPACT UPPER WAVE WILL MOVE ONSHORE OVER SOCAL EARLY SUNDAY...THEN TRANSLATE EAST ACROSS THE CENTRAL PLAINS BY MONDAY. SURFACE LOW WILL DEEPEN IN RESPONSE OVER THE CENTRAL PLAINS THROUGH THE PERIOD WITH STRONG WARM ADVECTION INTO THE REGION HELPING TO AMPLIFY THE MID/UPPER LEVEL RIDGING. H85 TEMPS WILL WARM TO AROUND 10C BY SUNDAY EVENING...AND 12C TO 13C BY MONDAY. CLIMO FROM NARR DATASET SHOWS MEDIAN TEMPS IN THE LOW 70S WHEN H85 TEMPS EXCEED AROUND 9C FOR THE LATTER HALF OF MARCH. WHILE THESE WARMER TEMPERATURES ALOFT WILL ARRIVE LATER IN THE DAY SUNDAY...THEY SHOULD BE DIRECTLY OVERHEAD ON MONDAY WHICH IS EXPECTED TO BE THE WARMEST DAY IN SOME TIME. BACKED OFF SLIGHTLY ON TEMPS FOR SUNDAY...AND WHILE I THINK AREAS ESPECIALLY IN THE WESTERN CWA STILL HAVE A GOOD CHANCE OF 60...IT MAY STRUGGLE TO REACH 60 IN CHICAGO AND EASTERN PORTIONS OF THE CWA DUE TO THE SLOWER ARRIVAL. THE MAIN CONCERNS FOR TEMPS MONDAY REVOLVE AROUND CONVECTIVE CHANCES AND CLOUD COVER WHICH WILL INHIBIT HOW WARM WE GET. H5 VORT TAKES ON A NEGATIVE TILT MONDAY AS IT LIFTS ACROSS THE MID-MISSOURI VALLEY AND LEFT EXIT REGION OF UPPER JET OVER THE AREA WILL PROVIDE ADDITIONAL BROAD SCALE ASCENT. LATEST THINKING ON TIMING OF THE LOW STILL HAS THE BETTER FORCING WELL TO THE WEST DURING PEAK HEATING WHEN SOME VERY MODEST SURFACE BASED INSTABILITY EXISTS. WITH THUNDERSTORMS DEVELOPING TO THE WEST...COULD SEE CIRRUS STREAMING OVERHEAD DURING THE DAY MONDAY WHICH WILL IMPACT TEMPS. WITH A PRETTY DYNAMIC SYSTEM...MAY BE ABLE TO OVERCOME THE LACK OF FAVORABLE THERMODYNAMICS FOR SOME SCATTERED SHOWERS AND THUNDERSTORMS TO DEVELOP...PARTICULARLY IN THE LATER AFTERNOON AND EVENING. REFINED POPS TO REFLECT THESE TIMING DETAILS BUT MAINTAINED 20 TO 30 PERCENT DUE TO COVERAGE CONCERNS. AS FAR AS TEMPS...REMAIN ON THE WARM SIDE OF THE SOLUTION ENVELOPE BUT WILL HOLD OFF ON GOING ABOVE GUIDANCE GIVEN THE EXPECTED CLOUD COVER AND UNCERTAINTY IN PRECIP. WINDS WILL BECOME PROGRESSIVELY BREEZY THROUGH THIS PERIOD...WITH GUSTS TO AROUND 20 MPH POSSIBLE ON SUNDAY AND EVEN BREEZIER CONDITIONS ON MONDAY. 50KT WINDS ARE NOTED AROUND 900MB MONDAY...AND WITH DEEP MIXING POSSIBLE...THE AREA MAY SEE 30MPH+ GUSTS AT THE SURFACE DURING THE AFTERNOON. TUESDAY THROUGH FRIDAY... AN ACTIVE PATTERN IS EXPECTED TO CONTINUE THROUGH THE REMAINDER OF THE UPCOMING WORK WEEK AS A SERIES OF WAVES PROGRESS ACROSS THE REGION. STILL CONSIDERABLE TIMING/TRACK DIFFERENCES THOUGH GUIDANCE DOES SEEM TO BE FAVORING A MORE SOUTHERLY/COOLER PATTERN... ESPECIALLY THE GFS WITH GOOD SUPPORT FROM THE GEFS. THE EMCWF MAINTAINS A WARMER SOLUTION...WITH BAROCLINIC ZONE VERY NEAR RESULTING IN A DECENT TEMPS SPREAD NORTH TO SOUTH ACROSS THE CWA. CONTINUE TO RUN WITH A MODEL CONSENSUS BLEND FOR TEMPS NEXT WEEK GIVEN THE HIGH DEGREE OF UNCERTAINTY...WHICH RESULTS IN WELL BELOW NORMAL TEMPS. DEUBELBEISS && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 16Z... * VARIABLE MVFR CIGS SCATTERING MID/LATE AFTERNOON. * NORTHEAST WINDS CONTINUING THROUGH THE EVENING. MDB //DISCUSSION...UPDATED 12Z... CIGS ARE STARTING TO BECOME MORE VARIABLE WITH SOME LIFTING OF BASES OCCURRING AS WELL. CLEARING IS STARTING TO MARCH SOUTHWARD DOWN THE LAKE AS WELL AND THIS LOOKS TO ARRIVE MID TO LATE AFTERNOON AT ORD/MDW/DPA/GYY. RFD LOOKS TO IMPROVE TO VFR IN THE NEXT HOUR OR SO. MDB FROM 12Z... HIGH PRESSURE MOVING TOWARD THE AREA WILL SUPPORT GRADUALLY CLEARING SKIES. WINDS REMAIN NORTH TO NORTHEAST FOR MOST OF THE DAY AHEAD OF THE RIDGE...THEN TURN EAST TOMORROW BEHIND IT. LENNING //ORD AND MDW CONFIDENCE...UPDATED 16Z... * MEDIUM CONFIDENCE IN TIMING OF SCATTERING CIGS. * HIGH CONFIDENCE IN WIND FORECAST. MDB //OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z... SUNDAY NIGHT...VFR. MONDAY...CHANCE OF TSRA. GUSTY SOUTH WINDS. TUESDAY...SLGT CHC OF RAIN DURING THE NIGHT. WEDNESDAY...RAIN AND MVFR LIKELY. THURSDAY AND FRIDAY...SLGT CHC OF RAIN AND SNOW. LENNING && .MARINE... 310 AM CDT WINDS GENERALLY WILL REMAIN NORTHERLY OR NORTHEASTERLY TODAY AHEAD OF AN APPROACHING HIGH PRESSURE RIDGE...THEN WILL VEER EAST AFTER THE RIDGE PASSES EARLY SUNDAY. THE EAST OR SOUTHEAST FLOW THEN PERSISTS THROUGH THE WEEKEND INTO EARLY NEXT WEEK. STRONG LOW PRESSURE MOVES THROUGH THE NORTHERN PART OF THE LAKE MONDAY NIGHT...LIKELY SUPPORTING A PERIOD OF GALES ON THE SOUTHERN HALF. THE WARM SOUTHERLY FLOW AHEAD OF THE LOW MONDAY AFTERNOON WILL BE VERY STRONG BUT MAY BE LESS EFFECTIVE AT CREATING GALES THAN THE WEAKER BUT COLDER WINDS BEHIND THE LOW ON MONDAY NIGHT AND TUESDAY. LENNING && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...NONE. && $$ 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 1024 AM CDT Sat Mar 29 2014 .DISCUSSION... ISSUED 1024 AM CDT Sat Mar 29 2014 Showers associated with low pressure in the eastern Tennessee Valley has now shifted east into Indiana and have updated forecast to reflect dry conditions across the entire CWA for the remainder of the day. Plenty of stratus continues to plague the region again today and main forecast issue is the potential for afternoon clearing and associated affect on high temps. A sliver of clearing is approaching the northern CWA but already starting to fill in with SC and a larger batch of stratus over NE IL is quickly advecting in behind this on NNE low level flow. Think clouds will hang tough as long as low level flow remains out of N/NNE which should last well into afternoon. As the low pulls further east winds will eventually come around to N/NNW advecting in drier air from NW IL and eastern IA, and subsidence off surface ridge to our west should help break up cloud deck. With this in mind have increased cloud cover through mid afternoon, lowered highs a degree or two, and slowed diurnal temp rise. 25 && .AVIATION... ISSUED 640 AM CDT Sat Mar 29 2014 MVFR cigs will continue at all TAF sites until sometime after 18z. Vis is lower at some sites, so have a TEMPO group for PIA/DEC/CMI and a TEMPO group for SPI with cigs below 1kft for a couple hours this morning. Clouds will hopefully scatter out this afternoon as models show some drier air advecting into the region; PIA and SPI first, followed by CMI last. Skies will eventually become clear, but not until the early evening time frame, right around sunset. Clear skies will then continue til tomorrow mroning. Winds will be northerly through the day, and then become light and variable tonight. Wind speeds this morning will be around 10kts, but then as the clouds scatter out, some mixing will occur and think that all sites could see gusts to around 20kts. Light winds expected tonight. Auten && .PREV DISCUSSION... ISSUED 227 AM CDT Sat Mar 29 2014 Surface low tracking across northern Mississippi early this morning, while an upper trough moves through Iowa and western Missouri. Area of showers streaming northward ahead of the upper trough has made it up to around Taylorville and Sullivan as of 2 am, although the leading edge has had to fight some dry air to make it that far. A rather active weather pattern is on tap for next week, with precipitation timing the primary forecast concern. SHORT TERM...Today through Monday: Will maintain some precipitation chances across the far eastern CWA for the first few hours after sunrise, until the trough moves into Illinois. Forecast soundings off the RAP model suggest some rain/snow mix north of I-70 until the ice crystals are lost by mid morning, with rain to the south. Otherwise, will see a decrease in clouds from west to east this afternoon, as ridge axis moves southeast out of the northern Plains. Decent warm air advection sets up early Sunday as the high drifts east of the state. With abundant sunshine, have sided more toward the MAV MOS highs in the lower to mid 60s, with temperatures in the mid to upper 60s on Monday. Monday looks to be fairly windy ahead of the next storm system, with Bufkit data suggesting wind gusts of 30-40 mph. Main surface low expected to track northeast into southern Minnesota by late afternoon, with the trailing cold front sweeping through the forecast area during the evening. Lower levels of the forecast soundings are rather dry though except for a brief window late afternoon and early evening, so will maintain PoP`s only in the 30 percent range. LONG TERM...Tuesday through Friday: Upper troughing begins to dig across California Tuesday night as a closed low moves southeast toward Los Angeles. As the week progresses, the question becomes how deep this remains and how fast the remaining closed low is ejected northeast. GFS and ECMWF maintain a rather wide range as a storm system develops over the Plains. The GFS remains much further south, with more of an inverted trough extending over southeast Illinois by Thursday morning. The ECMWF loiters a warm front just north of I-72 most of Wednesday and Thursday, before the parent low arrives Thursday evening. Both solutions would favor widespread showers, although the warmer ECMWF would suggest thunder being more widespread. Have not changed too much from the previous forecast, which favored the ECMWF and warmer temperatures. Geelhart && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
657 AM CDT SAT MAR 29 2014 .DISCUSSION... 302 AM CDT TODAY... THIS MORNING...RIDGE OF HIGH PRESSURE EXTENDS FROM LAKE SUPERIOR INTO THE MID MISSOURI VALLEY WHILE LOW PRESSURE LIES OVER MISSISSIPPI/ALABAMA. THIS LOW WILL LIFT NORTH INTO THE UPPER OHIO VALLEY TODAY RESULTING IN NORTHEASTERLY WINDS OFF OF LAKE MICHIGAN THROUGH THE DAY. SOME PRECIP MAY BRUSH THE FAR SOUTHEASTERN COUNTIES THIS MORNING...MAINLY IN THE FORM OF SNOW...THOUGH ANY ACCUMULATION WILL LIKELY BE CONFINED TO GRASSY AREAS AND ONLY A DUSTING IS EXPECTED. SPLIT CHANNEL IR IMAGERY SHOWS STRATUS STILL SPANS MUCH OF THE UPPER MIDWEST...AS FAR WEST AS CENTRAL IOWA AND NORTHWEST INTO CENTRAL WISCONSIN. EXPECT CLOUD COVER TO LINGER THROUGH AT LEAST MIDDAY...THEN ANTICYCLONIC FLOW WITH THE RIDGE AXIS SHOULD START TO BUILD IN FROM THE NORTHWEST THIS AFTERNOON AND EVENING WITH SKIES CLEARING. TEMPERATURES TODAY ARE EXPECTED TO WARM INTO THE LOW TO MID 40S...THOUGH WILL STAY IN THE 30S NEAR THE LAKE WITH THE OFFSHORE FLOW THROUGH THE DAY. SUNDAY AND MONDAY... COMPACT UPPER WAVE WILL MOVE ONSHORE OVER SOCAL EARLY SUNDAY...THEN TRANSLATE EAST ACROSS THE CENTRAL PLAINS BY MONDAY. SURFACE LOW WILL DEEPEN IN RESPONSE OVER THE CENTRAL PLAINS THROUGH THE PERIOD WITH STRONG WARM ADVECTION INTO THE REGION HELPING TO AMPLIFY THE MID/UPPER LEVEL RIDGING. H85 TEMPS WILL WARM TO AROUND 10C BY SUNDAY EVENING...AND 12C TO 13C BY MONDAY. CLIMO FROM NARR DATASET SHOWS MEDIAN TEMPS IN THE LOW 70S WHEN H85 TEMPS EXCEED AROUND 9C FOR THE LATTER HALF OF MARCH. WHILE THESE WARMER TEMPERATURES ALOFT WILL ARRIVE LATER IN THE DAY SUNDAY...THEY SHOULD BE DIRECTLY OVERHEAD ON MONDAY WHICH IS EXPECTED TO BE THE WARMEST DAY IN SOME TIME. BACKED OFF SLIGHTLY ON TEMPS FOR SUNDAY...AND WHILE I THINK AREAS ESPECIALLY IN THE WESTERN CWA STILL HAVE A GOOD CHANCE OF 60...IT MAY STRUGGLE TO REACH 60 IN CHICAGO AND EASTERN PORTIONS OF THE CWA DUE TO THE SLOWER ARRIVAL. THE MAIN CONCERNS FOR TEMPS MONDAY REVOLVE AROUND CONVECTIVE CHANCES AND CLOUD COVER WHICH WILL INHIBIT HOW WARM WE GET. H5 VORT TAKES ON A NEGATIVE TILT MONDAY AS IT LIFTS ACROSS THE MID-MISSOURI VALLEY AND LEFT EXIT REGION OF UPPER JET OVER THE AREA WILL PROVIDE ADDITIONAL BROAD SCALE ASCENT. LATEST THINKING ON TIMING OF THE LOW STILL HAS THE BETTER FORCING WELL TO THE WEST DURING PEAK HEATING WHEN SOME VERY MODEST SURFACE BASED INSTABILITY EXISTS. WITH THUNDERSTORMS DEVELOPING TO THE WEST...COULD SEE CIRRUS STREAMING OVERHEAD DURING THE DAY MONDAY WHICH WILL IMPACT TEMPS. WITH A PRETTY DYNAMIC SYSTEM...MAY BE ABLE TO OVERCOME THE LACK OF FAVORABLE THERMODYNAMICS FOR SOME SCATTERED SHOWERS AND THUNDERSTORMS TO DEVELOP...PARTICULARLY IN THE LATER AFTERNOON AND EVENING. REFINED POPS TO REFLECT THESE TIMING DETAILS BUT MAINTAINED 20 TO 30 PERCENT DUE TO COVERAGE CONCERNS. AS FAR AS TEMPS...REMAIN ON THE WARM SIDE OF THE SOLUTION ENVELOPE BUT WILL HOLD OFF ON GOING ABOVE GUIDANCE GIVEN THE EXPECTED CLOUD COVER AND UNCERTAINTY IN PRECIP. WINDS WILL BECOME PROGRESSIVELY BREEZY THROUGH THIS PERIOD...WITH GUSTS TO AROUND 20 MPH POSSIBLE ON SUNDAY AND EVEN BREEZIER CONDITIONS ON MONDAY. 50KT WINDS ARE NOTED AROUND 900MB MONDAY...AND WITH DEEP MIXING POSSIBLE...THE AREA MAY SEE 30MPH+ GUSTS AT THE SURFACE DURING THE AFTERNOON. TUESDAY THROUGH FRIDAY... AN ACTIVE PATTERN IS EXPECTED TO CONTINUE THROUGH THE REMAINDER OF THE UPCOMING WORK WEEK AS A SERIES OF WAVES PROGRESS ACROSS THE REGION. STILL CONSIDERABLE TIMING/TRACK DIFFERENCES THOUGH GUIDANCE DOES SEEM TO BE FAVORING A MORE SOUTHERLY/COOLER PATTERN... ESPECIALLY THE GFS WITH GOOD SUPPORT FROM THE GEFS. THE EMCWF MAINTAINS A WARMER SOLUTION...WITH BAROCLINIC ZONE VERY NEAR RESULTING IN A DECENT TEMPS SPREAD NORTH TO SOUTH ACROSS THE CWA. CONTINUE TO RUN WITH A MODEL CONSENSUS BLEND FOR TEMPS NEXT WEEK GIVEN THE HIGH DEGREE OF UNCERTAINTY...WHICH RESULTS IN WELL BELOW NORMAL TEMPS. DEUBELBEISS && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 12Z... * NORTHEAST WINDS FOR MOST OF THE DAY. * MVFR CEILINGS THIS MORNING BUT SCATTERING TO VFR THIS AFTERNOON. LENNING //DISCUSSION...UPDATED 12Z... HIGH PRESSURE MOVING TOWARD THE AREA WILL SUPPORT GRADUALLY CLEARING SKIES. WINDS REMAIN NORTH TO NORTHEAST FOR MOST OF THE DAY AHEAD OF THE RIDGE...THEN TURN EAST TOMORROW BEHIND IT. LENNING //ORD AND MDW CONFIDENCE...UPDATED 12Z... * MEDIUM CONFIDENCE IN TIMING OF VFR CEILINGS. * HIGH FOR OTHER ELEMENTS LENNING //OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z... SUNDAY NIGHT...VFR. MONDAY...CHANCE OF TSRA. GUSTY SOUTH WINDS. TUESDAY...SLGT CHC OF RAIN DURING THE NIGHT. WEDNESDAY...RAIN AND MVFR LIKELY. THURSDAY AND FRIDAY...SLGT CHC OF RAIN AND SNOW. LENNING && .MARINE... 310 AM CDT WINDS GENERALLY WILL REMAIN NORTHERLY OR NORTHEASTERLY TODAY AHEAD OF AN APPROACHING HIGH PRESSURE RIDGE...THEN WILL VEER EAST AFTER THE RIDGE PASSES EARLY SUNDAY. THE EAST OR SOUTHEAST FLOW THEN PERSISTS THROUGH THE WEEKEND INTO EARLY NEXT WEEK. STRONG LOW PRESSURE MOVES THROUGH THE NORTHERN PART OF THE LAKE MONDAY NIGHT...LIKELY SUPPORTING A PERIOD OF GALES ON THE SOUTHERN HALF. THE WARM SOUTHERLY FLOW AHEAD OF THE LOW MONDAY AFTERNOON WILL BE VERY STRONG BUT MAY BE LESS EFFECTIVE AT CREATING GALES THAN THE WEAKER BUT COLDER WINDS BEHIND THE LOW ON MONDAY NIGHT AND TUESDAY. LENNING && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...NONE. && $$ 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 640 AM CDT Sat Mar 29 2014 .DISCUSSION... ISSUED 227 AM CDT Sat Mar 29 2014 Surface low tracking across northern Mississippi early this morning, while an upper trough moves through Iowa and western Missouri. Area of showers streaming northward ahead of the upper trough has made it up to around Taylorville and Sullivan as of 2 am, although the leading edge has had to fight some dry air to make it that far. A rather active weather pattern is on tap for next week, with precipitation timing the primary forecast concern. SHORT TERM...Today through Monday: Will maintain some precipitation chances across the far eastern CWA for the first few hours after sunrise, until the trough moves into Illinois. Forecast soundings off the RAP model suggest some rain/snow mix north of I-70 until the ice crystals are lost by mid morning, with rain to the south. Otherwise, will see a decrease in clouds from west to east this afternoon, as ridge axis moves southeast out of the northern Plains. Decent warm air advection sets up early Sunday as the high drifts east of the state. With abundant sunshine, have sided more toward the MAV MOS highs in the lower to mid 60s, with temperatures in the mid to upper 60s on Monday. Monday looks to be fairly windy ahead of the next storm system, with Bufkit data suggesting wind gusts of 30-40 mph. Main surface low expected to track northeast into southern Minnesota by late afternoon, with the trailing cold front sweeping through the forecast area during the evening. Lower levels of the forecast soundings are rather dry though except for a brief window late afternoon and early evening, so will maintain PoP`s only in the 30 percent range. LONG TERM...Tuesday through Friday: Upper troughing begins to dig across California Tuesday night as a closed low moves southeast toward Los Angeles. As the week progresses, the question becomes how deep this remains and how fast the remaining closed low is ejected northeast. GFS and ECMWF maintain a rather wide range as a storm system develops over the Plains. The GFS remains much further south, with more of an inverted trough extending over southeast Illinois by Thursday morning. The ECMWF loiters a warm front just north of I-72 most of Wednesday and Thursday, before the parent low arrives Thursday evening. Both solutions would favor widespread showers, although the warmer ECMWF would suggest thunder being more widespread. Have not changed too much from the previous forecast, which favored the ECMWF and warmer temperatures. Geelhart && .AVIATION... ISSUED 640 AM CDT Sat Mar 29 2014 MVFR cigs will continue at all TAF sites until sometime after 18z. Vis is lower at some sites, so have a TEMPO group for PIA/DEC/CMI and a TEMPO group for SPI with cigs below 1kft for a couple hours this morning. Clouds will hopefully scatter out this afternoon as models show some drier air advecting into the region; PIA and SPI first, followed by CMI last. Skies will eventually become clear, but not until the early evening time frame, right around sunset. Clear skies will then continue til tomorrow mroning. Winds will be northerly through the day, and then become light and variable tonight. Wind speeds this morning will be around 10kts, but then as the clouds scatter out, some mixing will occur and think that all sites could see gusts to around 20kts. Light winds expected tonight. Auten && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
304 AM CDT SAT MAR 29 2014 .DISCUSSION... 302 AM CDT TODAY... THIS MORNING...RIDGE OF HIGH PRESSURE EXTENDS FROM LAKE SUPERIOR INTO THE MID MISSOURI VALLEY WHILE LOW PRESSURE LIES OVER MISSISSIPPI/ALABAMA. THIS LOW WILL LIFT NORTH INTO THE UPPER OHIO VALLEY TODAY RESULTING IN NORTHEASTERLY WINDS OFF OF LAKE MICHIGAN THROUGH THE DAY. SOME PRECIP MAY BRUSH THE FAR SOUTHEASTERN COUNTIES THIS MORNING...MAINLY IN THE FORM OF SNOW...THOUGH ANY ACCUMULATION WILL LIKELY BE CONFINED TO GRASSY AREAS AND ONLY A DUSTING IS EXPECTED. SPLIT CHANNEL IR IMAGERY SHOWS STRATUS STILL SPANS MUCH OF THE UPPER MIDWEST...AS FAR WEST AS CENTRAL IOWA AND NORTHWEST INTO CENTRAL WISCONSIN. EXPECT CLOUD COVER TO LINGER THROUGH AT LEAST MIDDAY...THEN ANTICYCLONIC FLOW WITH THE RIDGE AXIS SHOULD START TO BUILD IN FROM THE NORTHWEST THIS AFTERNOON AND EVENING WITH SKIES CLEARING. TEMPERATURES TODAY ARE EXPECTED TO WARM INTO THE LOW TO MID 40S...THOUGH WILL STAY IN THE 30S NEAR THE LAKE WITH THE OFFSHORE FLOW THROUGH THE DAY. SUNDAY AND MONDAY... COMPACT UPPER WAVE WILL MOVE ONSHORE OVER SOCAL EARLY SUNDAY...THEN TRANSLATE EAST ACROSS THE CENTRAL PLAINS BY MONDAY. SURFACE LOW WILL DEEPEN IN RESPONSE OVER THE CENTRAL PLAINS THROUGH THE PERIOD WITH STRONG WARM ADVECTION INTO THE REGION HELPING TO AMPLIFY THE MID/UPPER LEVEL RIDGING. H85 TEMPS WILL WARM TO AROUND 10C BY SUNDAY EVENING...AND 12C TO 13C BY MONDAY. CLIMO FROM NARR DATASET SHOWS MEDIAN TEMPS IN THE LOW 70S WHEN H85 TEMPS EXCEED AROUND 9C FOR THE LATTER HALF OF MARCH. WHILE THESE WARMER TEMPERATURES ALOFT WILL ARRIVE LATER IN THE DAY SUNDAY...THEY SHOULD BE DIRECTLY OVERHEAD ON MONDAY WHICH IS EXPECTED TO BE THE WARMEST DAY IN SOME TIME. BACKED OFF SLIGHTLY ON TEMPS FOR SUNDAY...AND WHILE I THINK AREAS ESPECIALLY IN THE WESTERN CWA STILL HAVE A GOOD CHANCE OF 60...IT MAY STRUGGLE TO REACH 60 IN CHICAGO AND EASTERN PORTIONS OF THE CWA DUE TO THE SLOWER ARRIVAL. THE MAIN CONCERNS FOR TEMPS MONDAY REVOLVE AROUND CONVECTIVE CHANCES AND CLOUD COVER WHICH WILL INHIBIT HOW WARM WE GET. H5 VORT TAKES ON A NEGATIVE TILT MONDAY AS IT LIFTS ACROSS THE MID-MISSOURI VALLEY AND LEFT EXIT REGION OF UPPER JET OVER THE AREA WILL PROVIDE ADDITIONAL BROAD SCALE ASCENT. LATEST THINKING ON TIMING OF THE LOW STILL HAS THE BETTER FORCING WELL TO THE WEST DURING PEAK HEATING WHEN SOME VERY MODEST SURFACE BASED INSTABILITY EXISTS. WITH THUNDERSTORMS DEVELOPING TO THE WEST...COULD SEE CIRRUS STREAMING OVERHEAD DURING THE DAY MONDAY WHICH WILL IMPACT TEMPS. WITH A PRETTY DYNAMIC SYSTEM...MAY BE ABLE TO OVERCOME THE LACK OF FAVORABLE THERMODYNAMICS FOR SOME SCATTERED SHOWERS AND THUNDERSTORMS TO DEVELOP...PARTICULARLY IN THE LATER AFTERNOON AND EVENING. REFINED POPS TO REFLECT THESE TIMING DETAILS BUT MAINTAINED 20 TO 30 PERCENT DUE TO COVERAGE CONCERNS. AS FAR AS TEMPS...REMAIN ON THE WARM SIDE OF THE SOLUTION ENVELOPE BUT WILL HOLD OFF ON GOING ABOVE GUIDANCE GIVEN THE EXPECTED CLOUD COVER AND UNCERTAINTY IN PRECIP. WINDS WILL BECOME PROGRESSIVELY BREEZY THROUGH THIS PERIOD...WITH GUSTS TO AROUND 20 MPH POSSIBLE ON SUNDAY AND EVEN BREEZIER CONDITIONS ON MONDAY. 50KT WINDS ARE NOTED AROUND 900MB MONDAY...AND WITH DEEP MIXING POSSIBLE...THE AREA MAY SEE 30MPH+ GUSTS AT THE SURFACE DURING THE AFTERNOON. TUESDAY THROUGH FRIDAY... AN ACTIVE PATTERN IS EXPECTED TO CONTINUE THROUGH THE REMAINDER OF THE UPCOMING WORK WEEK AS A SERIES OF WAVES PROGRESS ACROSS THE REGION. STILL CONSIDERABLE TIMING/TRACK DIFFERENCES THOUGH GUIDANCE DOES SEEM TO BE FAVORING A MORE SOUTHERLY/COOLER PATTERN... ESPECIALLY THE GFS WITH GOOD SUPPORT FROM THE GEFS. THE EMCWF MAINTAINS A WARMER SOLUTION...WITH BAROCLINIC ZONE VERY NEAR RESULTING IN A DECENT TEMPS SPREAD NORTH TO SOUTH ACROSS THE CWA. CONTINUE TO RUN WITH A MODEL CONSENSUS BLEND FOR TEMPS NEXT WEEK GIVEN THE HIGH DEGREE OF UNCERTAINTY...WHICH RESULTS IN WELL BELOW NORMAL TEMPS. DEUBELBEISS && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 06Z... * A PERIOD OF LIGHT SNOW IS POSSIBLE OVERNIGHT AND TOWARD MORNING. THIS WOULD MOST LIKELY BE WEST OF THE ORD/MDW AREA. * EAST WINDS BECOMING NORTHEAST WITH MVFR CEILINGS PERSISTING INTO MID TO LATE MORNING. LENNING //DISCUSSION...UPDATED 06Z... RADAR RETURNS ARE SHOWING AN ELEVATED BAND OF SNOW ACROSS EASTERN IOWA AND NW ILLINOIS. 06Z HOURLY SURFACE OBSERVATIONS HAVE YET TO SHOW ANYTHING REACHING THE GROUND...AND THE FORECAST MODELS THAT DEPICT THIS FEATURE KEEP IT LIMITED TO THE RFD AREA RATHER THAN MOVING IT EAST. THAT LEAVES MVFR CIGS AND EASTERLY WINDS THROUGH THE PREDAWN HOURS. WINDS GRADUALLY TURN MORE NORTHERLY TOWARD MORNING BUT PROBABLY WILL NOT GO AROUND TO WEST OF NORTH. INSTEAD THEY AGAIN GO MORE EASTERLY TOWARD EVENING AS A RIDGE OF HIGH PRESSURE MOVES INTO THE AREA. WITH THIS HIGH SHOULD COME SCATTERING CEILINGS AT SOME POINT TOWARD LATE MORNING OR EARLY AFTERNOON. LENNING //ORD AND MDW CONFIDENCE...UPDATED 06Z... * HIGH CONFIDENCE FOR ALL ELEMENTS. LENNING //OUTLOOK FOR ORD/MDW FOR 12Z SUNDAY-12Z FRIDAY...UPDATED 00Z... SUNDAY...VFR. MONDAY...CHANCE OF TSRA. GUSTY SOUTH WINDS. TUESDAY...SLGT CHC OF RAIN DURING THE NIGHT. WEDNESDAY...RAIN AND MVFR LIKELY. THURSDAY...SLGT CHC OF RAIN AND SNOW. MTF && .MARINE... 117 PM CDT FAIRLY TYPICAL ACTIVE SPRING WEATHER PATTERN EXPECTED THROUGH NEXT WEEK. HIGH PRESSURE SHOULD MOVE ACROSS THE LAKES THIS WEEKEND BUT A SYSTEM PASSING TO OUR SOUTH THROUGH THE TENNESSEE VALLEY SHOULD RESULT IN A BIT OF A NORTH WIND OVER SOUTHERN PORTIONS OF THE LAKE. ANOTHER LOW WILL PASS WELL TO OUR NORTH ON SUNDAY RESULTING IN A WIND SHIFT TO THE SOUTH FOLLOWED BY YET ANOTHER...MUCH STRONGER LOW OVER THE PLAINS WHICH SHOULD RESULT IN STRONG SOUTHERLY WINDS MONDAY. STABILITY ISSUES LOOK TO COME INTO PLAY AS 60F TEMPS RUN INTO THE MARINE BOUNDARY LAYER AND RESULT IN VERY SHALLOW MIXING. GRADIENT LOOKS TO BE STRONG ENOUGH TO RESULT IN STRONG WINDS...THOUGH THE LIMITED MIXING COULD POTENTIALLY MAKE IT HARD TO REACH GALES EXCEPT PERHAPS IN THE OFFSHORE FLOW ALONG THE NEARSHORE. IZZI && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...NONE. && $$ 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 228 AM CDT Sat Mar 29 2014 .DISCUSSION... ISSUED 227 AM CDT Sat Mar 29 2014 Surface low tracking across northern Mississippi early this morning, while an upper trough moves through Iowa and western Missouri. Area of showers streaming northward ahead of the upper trough has made it up to around Taylorville and Sullivan as of 2 am, although the leading edge has had to fight some dry air to make it that far. A rather active weather pattern is on tap for next week, with precipitation timing the primary forecast concern. SHORT TERM...Today through Monday: Will maintain some precipitation chances across the far eastern CWA for the first few hours after sunrise, until the trough moves into Illinois. Forecast soundings off the RAP model suggest some rain/snow mix north of I-70 until the ice crystals are lost by mid morning, with rain to the south. Otherwise, will see a decrease in clouds from west to east this afternoon, as ridge axis moves southeast out of the northern Plains. Decent warm air advection sets up early Sunday as the high drifts east of the state. With abundant sunshine, have sided more toward the MAV MOS highs in the lower to mid 60s, with temperatures in the mid to upper 60s on Monday. Monday looks to be fairly windy ahead of the next storm system, with Bufkit data suggesting wind gusts of 30-40 mph. Main surface low expected to track northeast into southern Minnesota by late afternoon, with the trailing cold front sweeping through the forecast area during the evening. Lower levels of the forecast soundings are rather dry though except for a brief window late afternoon and early evening, so will maintain PoP`s only in the 30 percent range. LONG TERM...Tuesday through Friday: Upper troughing begins to dig across California Tuesday night as a closed low moves southeast toward Los Angeles. As the week progresses, the question becomes how deep this remains and how fast the remaining closed low is ejected northeast. GFS and ECMWF maintain a rather wide range as a storm system develops over the Plains. The GFS remains much further south, with more of an inverted trough extending over southeast Illinois by Thursday morning. The ECMWF loiters a warm front just north of I-72 most of Wednesday and Thursday, before the parent low arrives Thursday evening. Both solutions would favor widespread showers, although the warmer ECMWF would suggest thunder being more widespread. Have not changed too much from the previous forecast, which favored the ECMWF and warmer temperatures. Geelhart && .AVIATION... ISSUED 1150 PM CDT Fri Mar 28 2014 Surface wave over southeast Arkansas, a reflection of a southern stream mid-level wave, is moving northeast along stationary front. In addition, an inverted trough near the Mississippi River is associated with a northern stream wave. Moisture streaming ahead of the southern system is beginning to be pulled northward ahead of the inverted trough. precipitation will likely begin to develop in the eastern terminals over next few hours. CIGs have been low MVFR through Friday and have been relatively uniform across much of the region. These CIGs will likely remain in the 015-025 range until the inverted trough moves through Saturday morning. Abundant boundary layer moisture trapped beneath the inversion should make any CIG slow to rise and thin though should scatter out by early evening Saturday as ridge builds in from the west and drier air advects into the TAF sites. Northerly winds should increase early Saturday as low/trough pulls off to the east and gradient increases ahead of plains ridge. Ridge moves across terminals Saturday evening enabling winds to quickly diminish around sunset. Barker && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
404 PM EDT SAT MAR 29 2014 .SYNOPSIS... ISSUED AT 0404 PM EDT SAT MAR 29 2014 PRECIPITATION HAS NOW EXITED THE FORECAST AREA WITH CLOUDY AND COOL CONDITIONS REMAINING THROUGH THE AFTERNOON. OVERNIGHT LOWS WILL BE COLD IN THE LOW TO MID 20S BEFORE TEMPERATURES WARM UP NICELY ON SUNDAY INTO THE LOW TO MID 50S. EVEN WARMER CONDITIONS ARE ANTICIPATED ON MONDAY AS HIGH TEMPEARTURES RISE INTO THE MID 60S UNDER PARTLY CLOUDY SKIES. && .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 328 PM EDT SAT MAR 29 2014 NO SIG ISSUES TO WORRY ABOUT FOR THE SHORT TERM AS RAIN/SNOW THAT HAS FELL ACROSS MUCH OF THE SOUTHERN GREAT LAKES TODAY WAS NEARLY OUT OF THE FORECAST AREA. FOCUS WILL SHIFT TO CLEARING TONIGHT AND HOW WARM WE GET ON SUNDAY. BY IN LARGE THE HEAVIER SNOWBANDS HAVE DIMINISHED WITH REMAINING RAIN/SNOW ACROSS PORTIONS OF HENRY/PUTNAM AND ALLEN COUNTIES IN OHIO. SFC LOW WAS OVER NE TENNESSEE AT 18Z AND SLOWLY DEEPENING WITH AN INCREASING PRESSURE GRADIENT AROUND IT. THIS WILL KEEP SOMEWHAT BREEZY CONDITIONS MAINLY EAST INTO THIS EVENING BEFORE THE LOW SHIFTS EAST. LOW CLOUDS HAVE BEEN SLOW TO ERODE IN THE WEST AND NORTH WITH NAM AND RUC VARYING ON HANDLING OF CLEARING. RUC 925/850 MB RH PLOT HAVE HANDLED THINGS WELL AND LINGER LOW CLOUDS INTO LATE EVENING WITH NAM MUCH QUICKER ERODING MSTR. WITH VIS SAT SHOWING HINTS AT SOME THIN SPOTS STARTING TO APPEAR SO HAVE TRIED TO BLEND THE 2 MODELS WHICH STILL BRINGS GENERALLY CLEAR SKIES BY LATE EVENING. LOWS WILL DROP INTO THE 20S DESPITE COLDEST AIR WITH THE SYSTEM ALREADY EAST OF THE REGION AND WAA UNDERWAY LATER TONIGHT. SOME OF THIS WAA WILL BE REALIZED ON SUNDAY AS LOTS OF SUNSHINE ALLOWS FOR MIXING THROUGH AT LEAST 900 MB AND MAYBE A BIT HIGHER YIELDS HIGHS IN THE 50S. WOULDN`T BE ENTIRELY SURPRISED TO SEE SOME UPR 50S TO NEAR 60 IN FAR W/SW AREAS. && .LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY) ISSUED AT 328 PM EDT SAT MAR 29 2014 VERY FEW CHANGES TO OVERALL IDEA IN LONG TERM PERIOD. AN ACTIVE PATTERN WILL CONTINUE THROUGH THE PERIOD WITH NUMEROUS SHORT WAVES AND A QUASI STATIONARY BOUNDARY IN THE REGION. THIS SHOULD LEAD TO RATHER WET PERIOD WITH TEMPERATURES A LITTLE CLOSER TO NORMAL FOR EARLY APRIL. RIDGE WILL BE OVER THE AREA SUNDAY NIGHT PROVIDING CLEAR SKIES AND LIGHT WINDS. LOWS EXPECTED IN THE LOWER 30S EAST UNDER RIDGE AXIS TO UPPER 30S WEST WHERE WARM AIR ADVECTION ON BACK SIDE OF RIDGE WILL BE INCREASING. THIS WARMING SHOULD TRANSLATE TO A LARGE DIURNAL SWING ON MONDAY AS STRONG MIXING DEVELOPS AND WARM AIR ALOFT IS ALLOWED TO MIX TO SURFACE. SHOULD BECOME BREEZY AS WELL TO HELP BOOST TEMPERATURES. INCREASING HIGH CLOUDS IN AFTERNOON MAY TEMPER WARM UP BY A FEW DEGREES DEPENDING ON HOW THICK CLOUD CANOPY IS AND TIMING OF IT. STILL EXPECT 60S ALL AREAS WITH RUN AT MID TO UPPER 60S ACROSS THE AREA IF SKIES REMAIN MOSTLY SUNNY THROUGH AFTERNOON PEAK HEATING. NEXT OF MANY SHORT WAVES MOVES THROUGH THE LAKES REGION MONDAY NIGHT WITH A TRAILING COLD FRONT THROUGH THE CWA EARLY TUESDAY MORNING. ENOUGH MOISTURE AND WEAK LIFT TO WARRANT LOW CHANCE POPS BUT STRONGEST FORCING TO THE NORTH CLOSER TO MAIN LOW. WARMEST TEMPS OF THE DAY LIKELY IN MORNING BEFORE FROPA BUT DRYING PROFILES TUE AFTERNOON SUGGEST SUN COULD ALLOW FOR SOME REBOUND SIMILAR TO WHAT SOME LOCATIONS EXPERIENCED FRIDAY. DETAILS REMAIN UNCERTAIN FOR REMAINDER OF LONG TERM WITH AFOREMENTIONED COLD FRONT BECOMING STATIONARY NEAR OR JUST SOUTH OF CWA. SEVERAL SHORT WAVES ARE EXPECTED WEDNESDAY INTO FRIDAY WITH ASSOCIATED SURFACE WAVES RIPPLING ALONG FRONTAL BOUNDARY. SEVERAL CHANCES FOR RAINFALL DURING THE PERIOD WITH UNCERTAINTY IN TIMING. THUS A CONTINUATION OF BROAD HIGH CHANCE POP CONTINUES WITH FURTHER INCREASE LIKELY AS TIME NEARS. WITH INCREASING PWATS AND THETA E AIR...MODERATE TO LOCALLY HEAVY RAINFALL AMOUNTS STILL PLAUSIBLE. TEMPS DURING THIS PERIOD LIKELY NEAR NORMAL SOUTH AND SLIGHTLY BELOW NORMAL NORTH BUT IF FRONT WAVERS NORTH OR SOUTH...SIGNIFICANT CHANGES IN TEMPERATURE FORECASTS WOULD BE EXPECTED. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 138 PM EDT SAT MAR 29 2014 WITH PRECIP ISSUES NOW OUT OF THE WAY AT BOTH SITES FOCUS WILL BE ON TIMING OF DEPARTURE OF LOW CLOUDS AND RETURN OF VFR CONDITIONS. WESTERN EDGE OF THE RAIN/SNOW SHIELD CLEARED KFWA OVER THE PAST 20 MINUTES WITH LITTLE MORE THAN SOME DRIZZLE/VRY LGT RAIN LEFT IN ITS WAKE. VSBYS WILL REMAIN MVFR DUE TO FOG...BUT CIGS WILL REMAIN THE BIGGER ISSUE SITTING AROUND 1000 TO 1500 FT. A LOW RISE IN CIGS IS EXPECTED...FIRST AT KSBN WHERE CIGS WILL COME UP TO 2500 TO 3000 FT LATER THIS AFTERNOON. SLOWER PROGRESS OF LOW CLOUDS EXPECTED AT KFWA GIVEN PROXIMITY OF SFC LOW TO THE SE. HOWEVER THEY WILL CATCH UP WITH TIME. RECENT RUC DATA HAD A GOOD HANDLE ON CLOUD COVER AND FOLLOWED CLOSELY THROUGH TONIGHT. ONCE THE CLOUDS DEPART VFR CONDITIONS WILL PREVAIL INTO TOMORROW. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...NONE. MI...NONE. OH...NONE. LM...NONE. && $$ SYNOPSIS...LOTHAMER SHORT TERM...FISHER LONG TERM...LASHLEY AVIATION...FISHER VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.NORTHERNIN.GOV WWW.TWITTER.COM/NWSIWX WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
331 PM EDT SAT MAR 29 2014 .SYNOPSIS... ISSUED AT 1022 AM EDT SAT MAR 29 2014 A LOW PRESSURE SYSTEM WILL BE PASSING THROUGH THE SOUTHEASTERN UNITED STATES TODAY AND THE CENTER WILL MOVE TO THE WASHINGTON D.C. AREA BY TOMORROW MORNING. THIS SYSTEM WILL PASS SOME PRECIPITATION THROUGH THE REGION TODAY IN THE FORM OF RAIN IN THE FAR SOUTH...MIX OF RAIN AND SNOW IN THE CENTRAL AREAS...AND MAINLY SNOW IN THE NORTH. AREAS IN THE CENTRAL TO NORTHERN PART OF THE REGION COULD SEE THE PRECIPITATION START OUT AS RAIN THEN SWITCH TO A MIX BEFORE FINALLY ALL SNOW. SNOWFALL AMOUNTS ARE EXPECTED TO BE SMALL. HIGH TEMPERATURES TODAY WILL RANGE FROM THE UPPER 30S IN THE SOUTHEASTERN HALF OF THE REGION TO THE LOWER 40S IN THE NORTHWESTERN HALF. TONIGHT WILL BE DRY ACROSS THE REGION WITH CLEARING SKIES AND TEMPERATURES DROPPING IN TO THE 20S. && .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 328 PM EDT SAT MAR 29 2014 NO SIG ISSUES TO WORRY ABOUT FOR THE SHORT TERM AS RAIN/SNOW THAT HAS FELL ACROSS MUCH OF THE SOUTHERN GREAT LAKES TODAY WAS NEARLY OUT OF THE FORECAST AREA. FOCUS WILL SHIFT TO CLEARING TONIGHT AND HOW WARM WE GET ON SUNDAY. BY IN LARGE THE HEAVIER SNOWBANDS HAVE DIMINISHED WITH REMAINING RAIN/SNOW ACROSS PORTIONS OF HENRY/PUTNAM AND ALLEN COUNTIES IN OHIO. SFC LOW WAS OVER NE TENNESSEE AT 18Z AND SLOWLY DEEPENING WITH AN INCREASING PRESSURE GRADIENT AROUND IT. THIS WILL KEEP SOMEWHAT BREEZY CONDITIONS MAINLY EAST INTO THIS EVENING BEFORE THE LOW SHIFTS EAST. LOW CLOUDS HAVE BEEN SLOW TO ERODE IN THE WEST AND NORTH WITH NAM AND RUC VARYING ON HANDLING OF CLEARING. RUC 925/850 MB RH PLOT HAVE HANDLED THINGS WELL AND LINGER LOW CLOUDS INTO LATE EVENING WITH NAM MUCH QUICKER ERODING MSTR. WITH VIS SAT SHOWING HINTS AT SOME THIN SPOTS STARTING TO APPEAR SO HAVE TRIED TO BLEND THE 2 MODELS WHICH STILL BRINGS GENERALLY CLEAR SKIES BY LATE EVENING. LOWS WILL DROP INTO THE 20S DESPITE COLDEST AIR WITH THE SYSTEM ALREADY EAST OF THE REGION AND WAA UNDERWAY LATER TONIGHT. SOME OF THIS WAA WILL BE REALIZED ON SUNDAY AS LOTS OF SUNSHINE ALLOWS FOR MIXING THROUGH AT LEAST 900 MB AND MAYBE A BIT HIGHER YIELDS HIGHS IN THE 50S. WOULDN`T BE ENTIRELY SURPRISED TO SEE SOME UPR 50S TO NEAR 60 IN FAR W/SW AREAS. && .LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY) ISSUED AT 328 PM EDT SAT MAR 29 2014 VERY FEW CHANGES TO OVERALL IDEA IN LONG TERM PERIOD. AN ACTIVE PATTERN WILL CONTINUE THROUGH THE PERIOD WITH NUMEROUS SHORT WAVES AND A QUASI STATIONARY BOUNDARY IN THE REGION. THIS SHOULD LEAD TO RATHER WET PERIOD WITH TEMPERATURES A LITTLE CLOSER TO NORMAL FOR EARLY APRIL. RIDGE WILL BE OVER THE AREA SUNDAY NIGHT PROVIDING CLEAR SKIES AND LIGHT WINDS. LOWS EXPECTED IN THE LOWER 30S EAST UNDER RIDGE AXIS TO UPPER 30S WEST WHERE WARM AIR ADVECTION ON BACK SIDE OF RIDGE WILL BE INCREASING. THIS WARMING SHOULD TRANSLATE TO A LARGE DIURNAL SWING ON MONDAY AS STRONG MIXING DEVELOPS AND WARM AIR ALOFT IS ALLOWED TO MIX TO SURFACE. SHOULD BECOME BREEZY AS WELL TO HELP BOOST TEMPERATURES. INCREASING HIGH CLOUDS IN AFTERNOON MAY TEMPER WARM UP BY A FEW DEGREES DEPENDING ON HOW THICK CLOUD CANOPY IS AND TIMING OF IT. STILL EXPECT 60S ALL AREAS WITH RUN AT MID TO UPPER 60S ACROSS THE AREA IF SKIES REMAIN MOSTLY SUNNY THROUGH AFTERNOON PEAK HEATING. NEXT OF MANY SHORT WAVES MOVES THROUGH THE LAKES REGION MONDAY NIGHT WITH A TRAILING COLD FRONT THROUGH THE CWA EARLY TUESDAY MORNING. ENOUGH MOISTURE AND WEAK LIFT TO WARRANT LOW CHANCE POPS BUT STRONGEST FORCING TO THE NORTH CLOSER TO MAIN LOW. WARMEST TEMPS OF THE DAY LIKELY IN MORNING BEFORE FROPA BUT DRYING PROFILES TUE AFTERNOON SUGGEST SUN COULD ALLOW FOR SOME REBOUND SIMILAR TO WHAT SOME LOCATIONS EXPERIENCED FRIDAY. DETAILS REMAIN UNCERTAIN FOR REMAINDER OF LONG TERM WITH AFOREMENTIONED COLD FRONT BECOMING STATIONARY NEAR OR JUST SOUTH OF CWA. SEVERAL SHORT WAVES ARE EXPECTED WEDNESDAY INTO FRIDAY WITH ASSOCIATED SURFACE WAVES RIPPLING ALONG FRONTAL BOUNDARY. SEVERAL CHANCES FOR RAINFALL DURING THE PERIOD WITH UNCERTAINTY IN TIMING. THUS A CONTINUATION OF BROAD HIGH CHANCE POP CONTINUES WITH FURTHER INCREASE LIKELY AS TIME NEARS. WITH INCREASING PWATS AND THETA E AIR...MODERATE TO LOCALLY HEAVY RAINFALL AMOUNTS STILL PLAUSIBLE. TEMPS DURING THIS PERIOD LIKELY NEAR NORMAL SOUTH AND SLIGHTLY BELOW NORMAL NORTH BUT IF FRONT WAVERS NORTH OR SOUTH...SIGNIFICANT CHANGES IN TEMPERATURE FORECASTS WOULD BE EXPECTED. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 138 PM EDT SAT MAR 29 2014 WITH PRECIP ISSUES NOW OUT OF THE WAY AT BOTH SITES FOCUS WILL BE ON TIMING OF DEPARTURE OF LOW CLOUDS AND RETURN OF VFR CONDITIONS. WESTERN EDGE OF THE RAIN/SNOW SHIELD CLEARED KFWA OVER THE PAST 20 MINUTES WITH LITTLE MORE THAN SOME DRIZZLE/VRY LGT RAIN LEFT IN ITS WAKE. VSBYS WILL REMAIN MVFR DUE TO FOG...BUT CIGS WILL REMAIN THE BIGGER ISSUE SITTING AROUND 1000 TO 1500 FT. A LOW RISE IN CIGS IS EXPECTED...FIRST AT KSBN WHERE CIGS WILL COME UP TO 2500 TO 3000 FT LATER THIS AFTERNOON. SLOWER PROGRESS OF LOW CLOUDS EXPECTED AT KFWA GIVEN PROXIMITY OF SFC LOW TO THE SE. HOWEVER THEY WILL CATCH UP WITH TIME. RECENT RUC DATA HAD A GOOD HANDLE ON CLOUD COVER AND FOLLOWED CLOSELY THROUGH TONIGHT. ONCE THE CLOUDS DEPART VFR CONDITIONS WILL PREVAIL INTO TOMORROW. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...NONE. MI...NONE. OH...NONE. LM...NONE. && $$ SYNOPSIS...LOTHAMER SHORT TERM...FISHER LONG TERM...LASHLEY AVIATION...FISHER VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.NORTHERNIN.GOV WWW.TWITTER.COM/NWSIWX WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
147 PM EDT SAT MAR 29 2014 .SYNOPSIS... ISSUED AT 1022 AM EDT SAT MAR 29 2014 A LOW PRESSURE SYSTEM WILL BE PASSING THROUGH THE SOUTHEASTERN UNITED STATES TODAY AND THE CENTER WILL MOVE TO THE WASHINGTON D.C. AREA BY TOMORROW MORNING. THIS SYSTEM WILL PASS SOME PRECIPITATION THROUGH THE REGION TODAY IN THE FORM OF RAIN IN THE FAR SOUTH...MIX OF RAIN AND SNOW IN THE CENTRAL AREAS...AND MAINLY SNOW IN THE NORTH. AREAS IN THE CENTRAL TO NORTHERN PART OF THE REGION COULD SEE THE PRECIPITATION START OUT AS RAIN THEN SWITCH TO A MIX BEFORE FINALLY ALL SNOW. SNOWFALL AMOUNTS ARE EXPECTED TO BE SMALL. HIGH TEMPERATURES TODAY WILL RANGE FROM THE UPPER 30S IN THE SOUTHEASTERN HALF OF THE REGION TO THE LOWER 40S IN THE NORTHWESTERN HALF. TONIGHT WILL BE DRY ACROSS THE REGION WITH CLEARING SKIES AND TEMPERATURES DROPPING IN TO THE 20S. && .UPDATE... ISSUED AT 138 PM EDT SAT MAR 29 2014 BULK OF SNOW/RAIN HAS SHIFTED EAST OF THE FORECAST AREA. BAND OF HEAVIER PRECIP HAS FINALLY LOST ITS PUNCH BUT RADAR TRENDS SUGGEST ANOTHER ONE TRYING TO TAKE SHAPE IN DEFORMATION ZONE FROM TOLEDO TO CELINA OHIO. SPORADIC REPORTS HAVE COME IN WITH SPOTS THAT RESIDE UNDER THESE BANDS SEEING A QUICK INCH OF SNOW IN AN HOUR ON GRASSY SURFACES....INCLUDING FT WAYNE AIRPORT AND VAN WERT. WILL HAVE TO WATCH PUTNAM/ALLEN COUNTY OHIO AREA WHERE INTENSITIES SEEM TO BE RAMPING UP QUICKLY. RADAR/MODELS TRENDS SUGGEST THIS SHOULD SHIFT EAST OVER THE NEXT COUPLE OF HOURS. WILL ADJUST GRIDS TO REFLECT PRECIP TRENDS. ALSO TEMPS STILL LOOK GOOD WITH STEADY OR EVEN SLOWLY RISING TRENDS NOTED ONCE THE PRECIP ENDS. CLOUDS WILL BE SLOW TO DEPART BUT WILL SLOWLY ERODE FROM NW TO SE. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 433 AM EDT SAT MAR 29 2014 ATTN THIS PD FOCUSED ON IMPRESSIVE SW DISTURBANCE OVR WRN IA EARLY THIS MORNING AND ITS SEWD AMPLIFICATION TWD THE MID ATL COAST BY SUN AFTN. 00Z GUIDANCE SPECTRUM IN VRY GOOD AGREEMENT W/HANDLING/EVOLUTION OF THIS SYS THROUGH THE PD. HWVR SUBSTANTIAL LWR MS VALLEY CONVN AND ASSOCD/MCV OVR WRN MS WILL CERTAINLY SQUASH BTR NWD MSTR RTN WELL S/E OF CWA CONFINES TDA AND ILLUSTRATED QUITE WELL BY DWINDLING SUCCESSIVE RUC SOLUTIONS. WHILE MID LVL CIRC INVOF DEEPENING SYS ALOFT IS IMPRESSIVE...SUBSTANTIAL LL DRY ENTRAINMENT ALG SRN PERIPHERY OF SE CANADA POLAR RIDGE XPCD. THIS WILL OBVIOUSLY BE DETRIMENTAL TO NW/NRN EXTENT OF PRECIP SHIELD AND BORNE OUT IN TIME HGT CROSS SECTIONS/POINT SNDGS WHICH SUGGEST MORE OF A VIRGA BOMB AND POTENTIAL BUST ALTOGETHER. THUS IN LIGHT OF SHRINKING IMPLIED HIGHRES CONSENSUS PRECIP RATES POTENTIAL SNOWFALL IMPACTS OVR SRN/SERN CWA LOOK MINIMAL. WILL IN THE LEAST TRUNCATE NWRN EXTENT OF MENTIONABLE POPS FURTHER AND ADJUST FOR PREFERRED TIMING. OTRWS PER PROGRESSIVE NATURE OF FLW PATTN ALOFT AND UPSTREAM EXTRAPOLATED SYS MOVEMENT WILL DROP PRIOR POP MENTION OVR FAR EAST THIS EVENING. && .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 433 AM EDT SAT MAR 29 2014 THERE ARE SURE SIGNS THIS UPCOMING WEEK OF A MILDER PATTERN...A PATTERN THAT HAS SEEMINGLY EVADED THE AREA FOR THE PAST 4 MONTHS. UPPER LEVEL RIDGING SHOULD INCREASE OVER THE REGION MONDAY IN ADVANCE OF A SHORTWAVE MOVING NORTHEAST. GIVEN GFS AND ECMWF 850 MB FCST TEMPS OF A SOLID 10C AND LITTLE REMAINING SNOW COVER...HIGHS SHOULD BE ABLE TO TOP 60 DEGREES OVER NEARLY ALL AREAS. THESE MILD TEMPERATURES ARE WELL SUPPORTED BY THE 00Z GFS MEX. AFTER MONDAY...ADDITIONAL SHORTWAVES WILL ENSUE...ACCOMPANIED BY WET WEATHER. FAVORED THE ECMWF DURING THE REST OF THE WEEK. THE ECMWF HAS BEEN CONSISTENT WITH THE MASS FIELDS NEXT WEEK. IN ADDITION... INCURSIONS OF GULF MOISTURE INTO THE AREA BY THE MIDDLE OF THE WEEK WILL BRING THE POTENTIAL FOR RAIN WEDNESDAY THROUGH FRIDAY. CONCERN FOR FLOODING GIVEN SATURATED GROUNDS...LIMITED VEGETATION AND ADDITIONAL RAIN. A GROUND CORE SOIL SAMPLE HERE AT THE OFFICE LAST NIGHT YIELDED NO FROZEN GROUND DOWN TO 14 INCHES WITH SATURATED SOILS. WILL HOLD OFF WITH A HYDRO OUTLOOK FOR NOW...BUT A FRONT SHOULD UNDULATE OVER THE AREA AS SHORT WAVES PASS. AFTER MONDAY... KEPT TEMPERATURES NEAR NORMAL...BUT HIGHS COULD STILL TOP 60 DEGREES AFTER MONDAY AS REFLECTED BY THE ECMWF IF THE FRONT MOVES BACK NORTH. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 138 PM EDT SAT MAR 29 2014 WITH PRECIP ISSUES NOW OUT OF THE WAY AT BOTH SITES FOCUS WILL BE ON TIMING OF DEPARTURE OF LOW CLOUDS AND RETURN OF VFR CONDITIONS. WESTERN EDGE OF THE RAIN/SNOW SHIELD CLEARED KFWA OVER THE PAST 20 MINUTES WITH LITTLE MORE THAN SOME DRIZZLE/VRY LGT RAIN LEFT IN ITS WAKE. VSBYS WILL REMAIN MVFR DUE TO FOG...BUT CIGS WILL REMAIN THE BIGGER ISSUE SITTING AROUND 1000 TO 1500 FT. A LOW RISE IN CIGS IS EXPECTED...FIRST AT KSBN WHERE CIGS WILL COME UP TO 2500 TO 3000 FT LATER THIS AFTERNOON. SLOWER PROGRESS OF LOW CLOUDS EXPECTED AT KFWA GIVEN PROXIMITY OF SFC LOW TO THE SE. HOWEVER THEY WILL CATCH UP WITH TIME. RECENT RUC DATA HAD A GOOD HANDLE ON CLOUD COVER AND FOLLOWED CLOSELY THROUGH TONIGHT. ONCE THE CLOUDS DEPART VFR CONDITIONS WILL PREVAIL INTO TOMORROW. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...NONE. MI...NONE. OH...NONE. LM...NONE. && $$ UPDATE...FISHER SYNOPSIS...LOTHAMER SHORT TERM...T LONG TERM...SKIPPER AVIATION...FISHER VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.NORTHERNIN.GOV WWW.TWITTER.COM/NWSIWX WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
1207 PM EDT SAT MAR 29 2014 .SYNOPSIS... ISSUED AT 1022 AM EDT SAT MAR 29 2014 A LOW PRESSURE SYSTEM WILL BE PASSING THROUGH THE SOUTHEASTERN UNITED STATES TODAY AND THE CENTER WILL MOVE TO THE WASHINGTON D.C. AREA BY TOMORROW MORNING. THIS SYSTEM WILL PASS SOME PRECIPITATION THROUGH THE REGION TODAY IN THE FORM OF RAIN IN THE FAR SOUTH...MIX OF RAIN AND SNOW IN THE CENTRAL AREAS...AND MAINLY SNOW IN THE NORTH. AREAS IN THE CENTRAL TO NORTHERN PART OF THE REGION COULD SEE THE PRECIPITATION START OUT AS RAIN THEN SWITCH TO A MIX BEFORE FINALLY ALL SNOW. SNOWFALL AMOUNTS ARE EXPECTED TO BE SMALL. HIGH TEMPERATURES TODAY WILL RANGE FROM THE UPPER 30S IN THE SOUTHEASTERN HALF OF THE REGION TO THE LOWER 40S IN THE NORTHWESTERN HALF. TONIGHT WILL BE DRY ACROSS THE REGION WITH CLEARING SKIES AND TEMPERATURES DROPPING IN TO THE 20S. && .UPDATE... ISSUED AT 1159 AM EDT SAT MAR 29 2014 PRECIP SHIELD FROM THE SOUTH AND MESO BANDING THAT HAS BEEN A PAIN THIS MORNING IN SOME SPOTS...WERE FINALLY COMING TOGETHER AND SHOULD PERSIST INTO THE AFTERNOON IN E/SE PORTIONS. LOCATIONS WHERE THE HEAVIEST BAND HAS SET UP HAVE SEEN VSBYS OF 1/4 TO 1/2 MILE AND UPWARDS OF AN INCH OR SO OF SNOW ON GRASSY AREAS. HAVE DECIDED TO GO WITH RAIN AND SNOW MIX INTO THIS AFTERNOON AS VARIABLE INTENSITY OF PRECIP WITH MAINLY SNOW IN THE MORE INTENSE BANDS AND A MIX OF RAIN/SNOW AT ONSET AND DURING LIGHTER PERIODS. WHILE ZONES AND GRIDS WILL COME BACK WITH SOME AREAS SEEING 1 TO 2 INCHES...THIS WILL BE SOMEWHAT DECEIVING SINCE ROADS SHOULD REMAIN WET AND THESE HIGHER AMOUNTS WILL ONLY OCCUR IN THE HEAVIER SNOW BANDS. THE MAIN BAND OF INTEREST AS OF WRITING THIS WAS LOCATED FROM NW JAY COUNTY THROUGH DECATUR TO NEAR PAULDING OHIO WHERE VSBYS ARE LIKELY LOW AT TIMES. AS FOR NW AREAS...ANY PRECIP WILL QUICKLY WIND DOWN OVER THE NEXT COUPLE HOURS. AREA OF CLEARING WAS TRYING TO WORK SOUTH ACROSS WI AND NW MI WITH SKIES STILL HOPEFULLY CLEARING OUT SOME TO ALLOW FOR TEMPS HEADING TOWARDS 40. WILL LEAVE TEMP FORECAST ALONE FOR NOW. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 433 AM EDT SAT MAR 29 2014 ATTN THIS PD FOCUSED ON IMPRESSIVE SW DISTURBANCE OVR WRN IA EARLY THIS MORNING AND ITS SEWD AMPLIFICATION TWD THE MID ATL COAST BY SUN AFTN. 00Z GUIDANCE SPECTRUM IN VRY GOOD AGREEMENT W/HANDLING/EVOLUTION OF THIS SYS THROUGH THE PD. HWVR SUBSTANTIAL LWR MS VALLEY CONVN AND ASSOCD/MCV OVR WRN MS WILL CERTAINLY SQUASH BTR NWD MSTR RTN WELL S/E OF CWA CONFINES TDA AND ILLUSTRATED QUITE WELL BY DWINDLING SUCCESSIVE RUC SOLUTIONS. WHILE MID LVL CIRC INVOF DEEPENING SYS ALOFT IS IMPRESSIVE...SUBSTANTIAL LL DRY ENTRAINMENT ALG SRN PERIPHERY OF SE CANADA POLAR RIDGE XPCD. THIS WILL OBVIOUSLY BE DETRIMENTAL TO NW/NRN EXTENT OF PRECIP SHIELD AND BORNE OUT IN TIME HGT CROSS SECTIONS/POINT SNDGS WHICH SUGGEST MORE OF A VIRGA BOMB AND POTENTIAL BUST ALTOGETHER. THUS IN LIGHT OF SHRINKING IMPLIED HIGHRES CONSENSUS PRECIP RATES POTENTIAL SNOWFALL IMPACTS OVR SRN/SERN CWA LOOK MINIMAL. WILL IN THE LEAST TRUNCATE NWRN EXTENT OF MENTIONABLE POPS FURTHER AND ADJUST FOR PREFERRED TIMING. OTRWS PER PROGRESSIVE NATURE OF FLW PATTN ALOFT AND UPSTREAM EXTRAPOLATED SYS MOVEMENT WILL DROP PRIOR POP MENTION OVR FAR EAST THIS EVENING. && .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 433 AM EDT SAT MAR 29 2014 THERE ARE SURE SIGNS THIS UPCOMING WEEK OF A MILDER PATTERN...A PATTERN THAT HAS SEEMINGLY EVADED THE AREA FOR THE PAST 4 MONTHS. UPPER LEVEL RIDGING SHOULD INCREASE OVER THE REGION MONDAY IN ADVANCE OF A SHORTWAVE MOVING NORTHEAST. GIVEN GFS AND ECMWF 850 MB FCST TEMPS OF A SOLID 10C AND LITTLE REMAINING SNOW COVER...HIGHS SHOULD BE ABLE TO TOP 60 DEGREES OVER NEARLY ALL AREAS. THESE MILD TEMPERATURES ARE WELL SUPPORTED BY THE 00Z GFS MEX. AFTER MONDAY...ADDITIONAL SHORTWAVES WILL ENSUE...ACCOMPANIED BY WET WEATHER. FAVORED THE ECMWF DURING THE REST OF THE WEEK. THE ECMWF HAS BEEN CONSISTENT WITH THE MASS FIELDS NEXT WEEK. IN ADDITION... INCURSIONS OF GULF MOISTURE INTO THE AREA BY THE MIDDLE OF THE WEEK WILL BRING THE POTENTIAL FOR RAIN WEDNESDAY THROUGH FRIDAY. CONCERN FOR FLOODING GIVEN SATURATED GROUNDS...LIMITED VEGETATION AND ADDITIONAL RAIN. A GROUND CORE SOIL SAMPLE HERE AT THE OFFICE LAST NIGHT YIELDED NO FROZEN GROUND DOWN TO 14 INCHES WITH SATURATED SOILS. WILL HOLD OFF WITH A HYDRO OUTLOOK FOR NOW...BUT A FRONT SHOULD UNDULATE OVER THE AREA AS SHORT WAVES PASS. AFTER MONDAY... KEPT TEMPERATURES NEAR NORMAL...BUT HIGHS COULD STILL TOP 60 DEGREES AFTER MONDAY AS REFLECTED BY THE ECMWF IF THE FRONT MOVES BACK NORTH. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 630 AM EDT SAT MAR 29 2014 NARROWING PCPN SHIELD OVR SE IL/SW IN ASSOCD W/APCH OF AMPLIFYING SW ROLLING SEWD OUT SRN IA LOOKS TO BE MAKING A BEELINE FOR KFWA TERMINAL BY DAYBREAK AND LINES UP EXCEEDINGLY WELL W/06Z LOCAL WRF. THUS WILL STAND PAT W/PRIOR 06Z ISSUANCE. BRIEF PD OF IFR CONDS PSBL TIMED W/CRUX OF SHRT DURATION MESOBAND BTWN 13-16Z ALTHOUGH PRECIP INTENSITY STILL APPEARS TO BE OF INSUFFICIENT INTENSITY TO PROVIDE AN ACCUMULATION ON HARD GROUND SFCS. OTRWS GENERAL MVFR CIG RESTRICTIONS TO PERSIST UNDERNEATH FNTL INVERSION ALOFT INTO MID AFTN BFR DEEP SUBSIDENT DRYING DVLPS IN WAKE OF DEPARTING MID LVL TROUGH. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...NONE. MI...NONE. OH...NONE. LM...NONE. && $$ UPDATE...FISHER SYNOPSIS...LOTHAMER SHORT TERM...T LONG TERM...SKIPPER AVIATION...T VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.NORTHERNIN.GOV WWW.TWITTER.COM/NWSIWX WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
1035 AM EDT SAT MAR 29 2014 .SYNOPSIS... ISSUED AT 1022 AM EDT SAT MAR 29 2014 A LOW PRESSURE SYSTEM WILL BE PASSING THROUGH THE SOUTHEASTERN UNITED STATES TODAY AND THE CENTER WILL MOVE TO THE WASHINGTON D.C. AREA BY TOMORROW MORNING. THIS SYSTEM WILL PASS SOME PRECIPITATION THROUGH THE REGION TODAY IN THE FORM OF RAIN IN THE FAR SOUTH...MIX OF RAIN AND SNOW IN THE CENTRAL AREAS...AND MAINLY SNOW IN THE NORTH. AREAS IN THE CENTRAL TO NORTHERN PART OF THE REGION COULD SEE THE PRECIPITATION START OUT AS RAIN THEN SWITCH TO A MIX BEFORE FINALLY ALL SNOW. SNOWFALL AMOUNTS ARE EXPECTED TO BE SMALL. HIGH TEMPERATURES TODAY WILL RANGE FROM THE UPPER 30S IN THE SOUTHEASTERN HALF OF THE REGION TO THE LOWER 40S IN THE NORTHWESTERN HALF. TONIGHT WILL BE DRY ACROSS THE REGION WITH CLEARING SKIES AND TEMPERATURES DROPPING IN TO THE 20S. && .UPDATE... ISSUED AT 926 AM EDT SAT MAR 29 2014 ZONES/GRIDS UPDATED TO EXPAND PRECIP AS FAR NW AS SOUTH BEND AND ADJUST TRENDS IN SE AREAS. IMPRESSIVE LIFT UNDERWAY ACROSS PORTIONS OF THE AREA WITH NARROW BAND OF HIGHER RETURNS SHOWING UP...RESULTING IN MAINLY SNOW AT THE SFC. BAND INITIALLY STARTED FROM ROUGHLY GRISSOM ARB TO WARSAW AND HAS BEEN SHIFTING SLOWLY EAST WITH TIME. EASTWARD EXTENT OF THE BAND AND NORTHERN EXTENT OF PRECIP SHIELD MOVING IN FROM CENTRAL INDIANA WAS BEING HAMPERED BY JUST ENOUGH SUBSIDENCE AND THE DRY NE FLOW. RUC DID AN AWESOME JOB OF CAPTURING THIS SETUP...WHICH MAKES THE FORECAST INTO THE AFTERNOON THAT MUCH MORE TROUBLESOME. 11Z RUC TAKES THE CURRENT BAND AND SLOWLY DISSIPATES IT AS IT PROGRESSES EAST AND THE MAIN AREA ACROSS CENTRAL INDIANA JUST GRAZING LIMA. HRRR MATCHES CLOSER TO WHAT WAS PREVIOUSLY GRIDDED INTO THIS AFTERNOON. WHILE DRY AIR CURRENTLY IN PLACE COULD GIVE SOME CREDENCE TO THIS...RADAR TRENDS SUGGEST THIS AREA WILL SLOWLY FILL IN WITH ALL PRECIP FOCUSING IN SE AREAS INTO THIS AFTERNOON. HAVE TRIED TO CAPTURE CURRENT AND EXPECTED TRENDS AS BEST AS POSSIBLE...WITH STRUGGLE BETWEEN RAIN AND SNOW LIKELY TO OCCUR MUCH OF THE DAY. ANY SNOW THAT DOES FALL SHOULD NOT CAUSE ANY IMPACTS AS SFC TEMPS SHOULD REMAIN NEAR OR JUST ABOVE FREEZING. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 433 AM EDT SAT MAR 29 2014 ATTN THIS PD FOCUSED ON IMPRESSIVE SW DISTURBANCE OVR WRN IA EARLY THIS MORNING AND ITS SEWD AMPLIFICATION TWD THE MID ATL COAST BY SUN AFTN. 00Z GUIDANCE SPECTRUM IN VRY GOOD AGREEMENT W/HANDLING/EVOLUTION OF THIS SYS THROUGH THE PD. HWVR SUBSTANTIAL LWR MS VALLEY CONVN AND ASSOCD/MCV OVR WRN MS WILL CERTAINLY SQUASH BTR NWD MSTR RTN WELL S/E OF CWA CONFINES TDA AND ILLUSTRATED QUITE WELL BY DWINDLING SUCCESSIVE RUC SOLUTIONS. WHILE MID LVL CIRC INVOF DEEPENING SYS ALOFT IS IMPRESSIVE...SUBSTANTIAL LL DRY ENTRAINMENT ALG SRN PERIPHERY OF SE CANADA POLAR RIDGE XPCD. THIS WILL OBVIOUSLY BE DETRIMENTAL TO NW/NRN EXTENT OF PRECIP SHIELD AND BORNE OUT IN TIME HGT CROSS SECTIONS/POINT SNDGS WHICH SUGGEST MORE OF A VIRGA BOMB AND POTENTIAL BUST ALTOGETHER. THUS IN LIGHT OF SHRINKING IMPLIED HIGHRES CONSENSUS PRECIP RATES POTENTIAL SNOWFALL IMPACTS OVR SRN/SERN CWA LOOK MINIMAL. WILL IN THE LEAST TRUNCATE NWRN EXTENT OF MENTIONABLE POPS FURTHER AND ADJUST FOR PREFERRED TIMING. OTRWS PER PROGRESSIVE NATURE OF FLW PATTN ALOFT AND UPSTREAM EXTRAPOLATED SYS MOVEMENT WILL DROP PRIOR POP MENTION OVR FAR EAST THIS EVENING. && .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 433 AM EDT SAT MAR 29 2014 THERE ARE SURE SIGNS THIS UPCOMING WEEK OF A MILDER PATTERN...A PATTERN THAT HAS SEEMINGLY EVADED THE AREA FOR THE PAST 4 MONTHS. UPPER LEVEL RIDGING SHOULD INCREASE OVER THE REGION MONDAY IN ADVANCE OF A SHORTWAVE MOVING NORTHEAST. GIVEN GFS AND ECMWF 850 MB FCST TEMPS OF A SOLID 10C AND LITTLE REMAINING SNOW COVER...HIGHS SHOULD BE ABLE TO TOP 60 DEGREES OVER NEARLY ALL AREAS. THESE MILD TEMPERATURES ARE WELL SUPPORTED BY THE 00Z GFS MEX. AFTER MONDAY...ADDITIONAL SHORTWAVES WILL ENSUE...ACCOMPANIED BY WET WEATHER. FAVORED THE ECMWF DURING THE REST OF THE WEEK. THE ECMWF HAS BEEN CONSISTENT WITH THE MASS FIELDS NEXT WEEK. IN ADDITION... INCURSIONS OF GULF MOISTURE INTO THE AREA BY THE MIDDLE OF THE WEEK WILL BRING THE POTENTIAL FOR RAIN WEDNESDAY THROUGH FRIDAY. CONCERN FOR FLOODING GIVEN SATURATED GROUNDS...LIMITED VEGETATION AND ADDITIONAL RAIN. A GROUND CORE SOIL SAMPLE HERE AT THE OFFICE LAST NIGHT YIELDED NO FROZEN GROUND DOWN TO 14 INCHES WITH SATURATED SOILS. WILL HOLD OFF WITH A HYDRO OUTLOOK FOR NOW...BUT A FRONT SHOULD UNDULATE OVER THE AREA AS SHORT WAVES PASS. AFTER MONDAY... KEPT TEMPERATURES NEAR NORMAL...BUT HIGHS COULD STILL TOP 60 DEGREES AFTER MONDAY AS REFLECTED BY THE ECMWF IF THE FRONT MOVES BACK NORTH. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 630 AM EDT SAT MAR 29 2014 NARROWING PCPN SHIELD OVR SE IL/SW IN ASSOCD W/APCH OF AMPLIFYING SW ROLLING SEWD OUT SRN IA LOOKS TO BE MAKING A BEELINE FOR KFWA TERMINAL BY DAYBREAK AND LINES UP EXCEEDINGLY WELL W/06Z LOCAL WRF. THUS WILL STAND PAT W/PRIOR 06Z ISSUANCE. BRIEF PD OF IFR CONDS PSBL TIMED W/CRUX OF SHRT DURATION MESOBAND BTWN 13-16Z ALTHOUGH PRECIP INTENSITY STILL APPEARS TO BE OF INSUFFICIENT INTENSITY TO PROVIDE AN ACCUMULATION ON HARD GROUND SFCS. OTRWS GENERAL MVFR CIG RESTRICTIONS TO PERSIST UNDERNEATH FNTL INVERSION ALOFT INTO MID AFTN BFR DEEP SUBSIDENT DRYING DVLPS IN WAKE OF DEPARTING MID LVL TROUGH. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...NONE. MI...NONE. OH...NONE. LM...NONE. && $$ UPDATE...FISHER SYNOPSIS...LOTHAMER SHORT TERM...T LONG TERM...SKIPPER AVIATION...T VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.NORTHERNIN.GOV WWW.TWITTER.COM/NWSIWX WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
939 AM EDT SAT MAR 29 2014 .SYNOPSIS... ISSUED AT 630 AM EDT SAT MAR 29 2014 LIGHT SNOW WILL BEGIN ACROSS PARTS THE AREA TOWARD SUNRISE AND CONTINUE THROUGH THIS MORNING. THE SNOW MAY BE MIXED WITH RAIN AT TIMES. TOTAL SNOWFALL ACCUMULATIONS UP TO AN INCH ARE EXPECTED SOUTHEAST OF US HIGHWAY 24. && .UPDATE... ISSUED AT 926 AM EDT SAT MAR 29 2014 ZONES/GRIDS UPDATED TO EXPAND PRECIP AS FAR NW AS SOUTH BEND AND ADJUST TRENDS IN SE AREAS. IMPRESSIVE LIFT UNDERWAY ACROSS PORTIONS OF THE AREA WITH NARROW BAND OF HIGHER RETURNS SHOWING UP...RESULTING IN MAINLY SNOW AT THE SFC. BAND INITIALLY STARTED FROM ROUGHLY GRISSOM ARB TO WARSAW AND HAS BEEN SHIFTING SLOWLY EAST WITH TIME. EASTWARD EXTENT OF THE BAND AND NORTHERN EXTENT OF PRECIP SHIELD MOVING IN FROM CENTRAL INDIANA WAS BEING HAMPERED BY JUST ENOUGH SUBSIDENCE AND THE DRY NE FLOW. RUC DID AN AWESOME JOB OF CAPTURING THIS SETUP...WHICH MAKES THE FORECAST INTO THE AFTERNOON THAT MUCH MORE TROUBLESOME. 11Z RUC TAKES THE CURRENT BAND AND SLOWLY DISSIPATES IT AS IT PROGRESSES EAST AND THE MAIN AREA ACROSS CENTRAL INDIANA JUST GRAZING LIMA. HRRR MATCHES CLOSER TO WHAT WAS PREVIOUSLY GRIDDED INTO THIS AFTERNOON. WHILE DRY AIR CURRENTLY IN PLACE COULD GIVE SOME CREDENCE TO THIS...RADAR TRENDS SUGGEST THIS AREA WILL SLOWLY FILL IN WITH ALL PRECIP FOCUSING IN SE AREAS INTO THIS AFTERNOON. HAVE TRIED TO CAPTURE CURRENT AND EXPECTED TRENDS AS BEST AS POSSIBLE...WITH STRUGGLE BETWEEN RAIN AND SNOW LIKELY TO OCCUR MUCH OF THE DAY. ANY SNOW THAT DOES FALL SHOULD NOT CAUSE ANY IMPACTS AS SFC TEMPS SHOULD REMAIN NEAR OR JUST ABOVE FREEZING. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 433 AM EDT SAT MAR 29 2014 ATTN THIS PD FOCUSED ON IMPRESSIVE SW DISTURBANCE OVR WRN IA EARLY THIS MORNING AND ITS SEWD AMPLIFICATION TWD THE MID ATL COAST BY SUN AFTN. 00Z GUIDANCE SPECTRUM IN VRY GOOD AGREEMENT W/HANDLING/EVOLUTION OF THIS SYS THROUGH THE PD. HWVR SUBSTANTIAL LWR MS VALLEY CONVN AND ASSOCD/MCV OVR WRN MS WILL CERTAINLY SQUASH BTR NWD MSTR RTN WELL S/E OF CWA CONFINES TDA AND ILLUSTRATED QUITE WELL BY DWINDLING SUCCESSIVE RUC SOLUTIONS. WHILE MID LVL CIRC INVOF DEEPENING SYS ALOFT IS IMPRESSIVE...SUBSTANTIAL LL DRY ENTRAINMENT ALG SRN PERIPHERY OF SE CANADA POLAR RIDGE XPCD. THIS WILL OBVIOUSLY BE DETRIMENTAL TO NW/NRN EXTENT OF PRECIP SHIELD AND BORNE OUT IN TIME HGT CROSS SECTIONS/POINT SNDGS WHICH SUGGEST MORE OF A VIRGA BOMB AND POTENTIAL BUST ALTOGETHER. THUS IN LIGHT OF SHRINKING IMPLIED HIGHRES CONSENSUS PRECIP RATES POTENTIAL SNOWFALL IMPACTS OVR SRN/SERN CWA LOOK MINIMAL. WILL IN THE LEAST TRUNCATE NWRN EXTENT OF MENTIONABLE POPS FURTHER AND ADJUST FOR PREFERRED TIMING. OTRWS PER PROGRESSIVE NATURE OF FLW PATTN ALOFT AND UPSTREAM EXTRAPOLATED SYS MOVEMENT WILL DROP PRIOR POP MENTION OVR FAR EAST THIS EVENING. && .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 433 AM EDT SAT MAR 29 2014 THERE ARE SURE SIGNS THIS UPCOMING WEEK OF A MILDER PATTERN...A PATTERN THAT HAS SEEMINGLY EVADED THE AREA FOR THE PAST 4 MONTHS. UPPER LEVEL RIDGING SHOULD INCREASE OVER THE REGION MONDAY IN ADVANCE OF A SHORTWAVE MOVING NORTHEAST. GIVEN GFS AND ECMWF 850 MB FCST TEMPS OF A SOLID 10C AND LITTLE REMAINING SNOW COVER...HIGHS SHOULD BE ABLE TO TOP 60 DEGREES OVER NEARLY ALL AREAS. THESE MILD TEMPERATURES ARE WELL SUPPORTED BY THE 00Z GFS MEX. AFTER MONDAY...ADDITIONAL SHORTWAVES WILL ENSUE...ACCOMPANIED BY WET WEATHER. FAVORED THE ECMWF DURING THE REST OF THE WEEK. THE ECMWF HAS BEEN CONSISTENT WITH THE MASS FIELDS NEXT WEEK. IN ADDITION... INCURSIONS OF GULF MOISTURE INTO THE AREA BY THE MIDDLE OF THE WEEK WILL BRING THE POTENTIAL FOR RAIN WEDNESDAY THROUGH FRIDAY. CONCERN FOR FLOODING GIVEN SATURATED GROUNDS...LIMITED VEGETATION AND ADDITIONAL RAIN. A GROUND CORE SOIL SAMPLE HERE AT THE OFFICE LAST NIGHT YIELDED NO FROZEN GROUND DOWN TO 14 INCHES WITH SATURATED SOILS. WILL HOLD OFF WITH A HYDRO OUTLOOK FOR NOW...BUT A FRONT SHOULD UNDULATE OVER THE AREA AS SHORT WAVES PASS. AFTER MONDAY... KEPT TEMPERATURES NEAR NORMAL...BUT HIGHS COULD STILL TOP 60 DEGREES AFTER MONDAY AS REFLECTED BY THE ECMWF IF THE FRONT MOVES BACK NORTH. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 630 AM EDT SAT MAR 29 2014 NARROWING PCPN SHIELD OVR SE IL/SW IN ASSOCD W/APCH OF AMPLIFYING SW ROLLING SEWD OUT SRN IA LOOKS TO BE MAKING A BEELINE FOR KFWA TERMINAL BY DAYBREAK AND LINES UP EXCEEDINGLY WELL W/06Z LOCAL WRF. THUS WILL STAND PAT W/PRIOR 06Z ISSUANCE. BRIEF PD OF IFR CONDS PSBL TIMED W/CRUX OF SHRT DURATION MESOBAND BTWN 13-16Z ALTHOUGH PRECIP INTENSITY STILL APPEARS TO BE OF INSUFFICIENT INTENSITY TO PROVIDE AN ACCUMULATION ON HARD GROUND SFCS. OTRWS GENERAL MVFR CIG RESTRICTIONS TO PERSIST UNDERNEATH FNTL INVERSION ALOFT INTO MID AFTN BFR DEEP SUBSIDENT DRYING DVLPS IN WAKE OF DEPARTING MID LVL TROUGH. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...NONE. MI...NONE. OH...NONE. LM...NONE. && $$ UPDATE...FISHER SYNOPSIS...SKIPPER SHORT TERM...T LONG TERM...SKIPPER AVIATION...T VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.NORTHERNIN.GOV WWW.TWITTER.COM/NWSIWX WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
630 AM EDT SAT MAR 29 2014 .SYNOPSIS... ISSUED AT 630 AM EDT SAT MAR 29 2014 LIGHT SNOW WILL BEGIN ACROSS PARTS THE AREA TOWARD SUNRISE AND CONTINUE THROUGH THIS MORNING. THE SNOW MAY BE MIXED WITH RAIN AT TIMES. TOTAL SNOWFALL ACCUMULATIONS UP TO AN INCH ARE EXPECTED SOUTHEAST OF US HIGHWAY 24. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 433 AM EDT SAT MAR 29 2014 ATTN THIS PD FOCUSED ON IMPRESSIVE SW DISTURBANCE OVR WRN IA EARLY THIS MORNING AND ITS SEWD AMPLIFICATION TWD THE MID ATL COAST BY SUN AFTN. 00Z GUIDANCE SPECTRUM IN VRY GOOD AGREEMENT W/HANDLING/EVOLUTION OF THIS SYS THROUGH THE PD. HWVR SUBSTANTIAL LWR MS VALLEY CONVN AND ASSOCD/MCV OVR WRN MS WILL CERTAINLY SQUASH BTR NWD MSTR RTN WELL S/E OF CWA CONFINES TDA AND ILLUSTRATED QUITE WELL BY DWINDLING SUCCESSIVE RUC SOLUTIONS. WHILE MID LVL CIRC INVOF DEEPENING SYS ALOFT IS IMPRESSIVE...SUBSTANTIAL LL DRY ENTRAINMENT ALG SRN PERIPHERY OF SE CANADA POLAR RIDGE XPCD. THIS WILL OBVIOUSLY BE DETRIMENTAL TO NW/NRN EXTENT OF PRECIP SHIELD AND BORNE OUT IN TIME HGT CROSS SECTIONS/POINT SNDGS WHICH SUGGEST MORE OF A VIRGA BOMB AND POTENTIAL BUST ALTOGETHER. THUS IN LIGHT OF SHRINKING IMPLIED HIGHRES CONSENSUS PRECIP RATES POTENTIAL SNOWFALL IMPACTS OVR SRN/SERN CWA LOOK MINIMAL. WILL IN THE LEAST TRUNCATE NWRN EXTENT OF MENTIONABLE POPS FURTHER AND ADJUST FOR PREFERRED TIMING. OTRWS PER PROGRESSIVE NATURE OF FLW PATTN ALOFT AND UPSTREAM EXTRAPOLATED SYS MOVEMENT WILL DROP PRIOR POP MENTION OVR FAR EAST THIS EVENING. && .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 433 AM EDT SAT MAR 29 2014 THERE ARE SURE SIGNS THIS UPCOMING WEEK OF A MILDER PATTERN...A PATTERN THAT HAS SEEMINGLY EVADED THE AREA FOR THE PAST 4 MONTHS. UPPER LEVEL RIDGING SHOULD INCREASE OVER THE REGION MONDAY IN ADVANCE OF A SHORTWAVE MOVING NORTHEAST. GIVEN GFS AND ECMWF 850 MB FCST TEMPS OF A SOLID 10C AND LITTLE REMAINING SNOW COVER...HIGHS SHOULD BE ABLE TO TOP 60 DEGREES OVER NEARLY ALL AREAS. THESE MILD TEMPERATURES ARE WELL SUPPORTED BY THE 00Z GFS MEX. AFTER MONDAY...ADDITIONAL SHORTWAVES WILL ENSUE...ACCOMPANIED BY WET WEATHER. FAVORED THE ECMWF DURING THE REST OF THE WEEK. THE ECMWF HAS BEEN CONSISTENT WITH THE MASS FIELDS NEXT WEEK. IN ADDITION... INCURSIONS OF GULF MOISTURE INTO THE AREA BY THE MIDDLE OF THE WEEK WILL BRING THE POTENTIAL FOR RAIN WEDNESDAY THROUGH FRIDAY. CONCERN FOR FLOODING GIVEN SATURATED GROUNDS...LIMITED VEGETATION AND ADDITIONAL RAIN. A GROUND CORE SOIL SAMPLE HERE AT THE OFFICE LAST NIGHT YIELDED NO FROZEN GROUND DOWN TO 14 INCHES WITH SATURATED SOILS. WILL HOLD OFF WITH A HYDRO OUTLOOK FOR NOW...BUT A FRONT SHOULD UNDULATE OVER THE AREA AS SHORT WAVES PASS. AFTER MONDAY... KEPT TEMPERATURES NEAR NORMAL...BUT HIGHS COULD STILL TOP 60 DEGREES AFTER MONDAY AS REFLECTED BY THE ECMWF IF THE FRONT MOVES BACK NORTH. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 630 AM EDT SAT MAR 29 2014 NARROWING PCPN SHIELD OVR SE IL/SW IN ASSOCD W/APCH OF AMPLIFYING SW ROLLING SEWD OUT SRN IA LOOKS TO BE MAKING A BEELINE FOR KFWA TERMINAL BY DAYBREAK AND LINES UP EXCEEDINGLY WELL W/06Z LOCAL WRF. THUS WILL STAND PAT W/PRIOR 06Z ISSUANCE. BRIEF PD OF IFR CONDS PSBL TIMED W/CRUX OF SHRT DURATION MESOBAND BTWN 13-16Z ALTHOUGH PRECIP INTENSITY STILL APPEARS TO BE OF INSUFFICIENT INTENSITY TO PROVIDE AN ACCUMULATION ON HARD GROUND SFCS. OTRWS GENERAL MVFR CIG RESTRICTIONS TO PERSIST UNDERNEATH FNTL INVERSION ALOFT INTO MID AFTN BFR DEEP SUBSIDENT DRYING DVLPS IN WAKE OF DEPARTING MID LVL TROUGH. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...NONE. MI...NONE. OH...NONE. LM...NONE. && $$ SYNOPSIS...SKIPPER SHORT TERM...T LONG TERM...SKIPPER AVIATION...T VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.NORTHERNIN.GOV WWW.TWITTER.COM/NWSIWX WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
437 AM EDT SAT MAR 29 2014 .SYNOPSIS... ISSUED AT 840 PM EDT FRI MAR 28 2014 LIGHT SNOW WILL BEGIN ACROSS THE AREA THIS MORNING HOURS. THE SNOW MAY BE MIXED WITH RAIN AT TIMES. TOTAL SNOWFALL ACCUMULATIONS UP TO AN INCH ARE EXPECTED SOUTHEAST OF US HIGHWAY 24. ONLY A TRACE OF SNOW EXPECTED ELSEWHERE. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 433 AM EDT SAT MAR 29 2014 ATTN THIS PD FOCUSED ON IMPRESSIVE SW DISTURBANCE OVR WRN IA EARLY THIS MORNING AND ITS SEWD AMPLIFICATION TWD THE MID ATL COAST BY SUN AFTN. 00Z GUIDANCE SPECTRUM IN VRY GOOD AGREEMENT W/HANDLING/EVOLUTION OF THIS SYS THROUGH THE PD. HWVR SUBSTANTIAL LWR MS VALLEY CONVN AND ASSOCD/MCV OVR WRN MS WILL CERTAINLY SQUASH BTR NWD MSTR RTN WELL S/E OF CWA CONFINES TDA AND ILLUSTRATED QUITE WELL BY DWINDLING SUCCESSIVE RUC SOLUTIONS. WHILE MID LVL CIRC INVOF DEEPENING SYS ALOFT IS IMPRESSIVE...SUBSTANTIAL LL DRY ENTRAINMENT ALG SRN PERIPHERY OF SE CANADA POLAR RIDGE XPCD. THIS WILL OBVIOUSLY BE DETRIMENTAL TO NW/NRN EXTENT OF PRECIP SHIELD AND BORNE OUT IN TIME HGT CROSS SECTIONS/POINT SNDGS WHICH SUGGEST MORE OF A VIRGA BOMB AND POTENTIAL BUST ALTOGETHER. THUS IN LIGHT OF SHRINKING IMPLIED HIGHRES CONSENSUS PRECIP RATES POTENTIAL SNOWFALL IMPACTS OVR SRN/SERN CWA LOOK MINIMAL. WILL IN THE LEAST TRUNCATE NWRN EXTENT OF MENTIONABLE POPS FURTHER AND ADJUST FOR PREFERRED TIMING. OTRWS PER PROGRESSIVE NATURE OF FLW PATTN ALOFT AND UPSTREAM EXTRAPOLATED SYS MOVEMENT WILL DROP PRIOR POP MENTION OVR FAR EAST THIS EVENING. && .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 433 AM EDT SAT MAR 29 2014 THERE ARE SURE SIGNS THIS UPCOMING WEEK OF A MILDER PATTERN...A PATTERN THAT HAS SEEMINGLY EVADED THE AREA FOR THE PAST 4 MONTHS. UPPER LEVEL RIDGING SHOULD INCREASE OVER THE REGION MONDAY IN ADVANCE OF A SHORTWAVE MOVING NORTHEAST. GIVEN GFS AND ECMWF 850 MB FCST TEMPS OF A SOLID 10C AND LITTLE REMAINING SNOW COVER...HIGHS SHOULD BE ABLE TO TOP 60 DEGREES OVER NEARLY ALL AREAS. THESE MILD TEMPERATURES ARE WELL SUPPORTED BY THE 00Z GFS MEX. AFTER MONDAY...ADDITIONAL SHORTWAVES WILL ENSUE...ACCOMPANIED BY WET WEATHER. FAVORED THE ECMWF DURING THE REST OF THE WEEK. THE ECMWF HAS BEEN CONSISTENT WITH THE MASS FIELDS NEXT WEEK. IN ADDITION... INCURSIONS OF GULF MOISTURE INTO THE AREA BY THE MIDDLE OF THE WEEK WILL BRING THE POTENTIAL FOR RAIN WEDNESDAY THROUGH FRIDAY. CONCERN FOR FLOODING GIVEN SATURATED GROUNDS...LIMITED VEGETATION AND ADDITIONAL RAIN. A GROUND CORE SOIL SAMPLE HERE AT THE OFFICE LAST NIGHT YIELDED NO FROZEN GROUND DOWN TO 14 INCHES WITH SATURATED SOILS. WILL HOLD OFF WITH A HYDRO OUTLOOK FOR NOW...BUT A FRONT SHOULD UNDULATE OVER THE AREA AS SHORT WAVES PASS. AFTER MONDAY... KEPT TEMPERATURES NEAR NORMAL...BUT HIGHS COULD STILL TOP 60 DEGREES AFTER MONDAY AS REFLECTED BY THE ECMWF IF THE FRONT MOVES BACK NORTH. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 128 AM EDT SAT MAR 29 2014 SUBSTANTIAL POST FNTL INVERSION BENEATH INCREASING MID LVL MSTR ADVTN INADV OF AMPLIFYING SW DISTURBANCE OVR WRN IA WILL LOCK IN MVFR STRATOCU CIGS THROUGH SAT MORNING. VSBY RESTRICTIONS LIKELY AT KFWA AS BURGEONING MID LVL CIRC DVLPS TWD 12Z BUT XPCD TO RAPIDLY BREAKDOWN TWD 18Z. STG SUBSIDENT DRYING WIL FOLLOW IN WAKE OF EWD EJECTING SYS LT THIS AFTN W/VFR CONDS DVLPG INTO ERLY EVENING. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...NONE. MI...NONE. OH...NONE. LM...NONE. && $$ SYNOPSIS...SKIPPER SHORT TERM...T LONG TERM...SKIPPER AVIATION...T VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.NORTHERNIN.GOV WWW.TWITTER.COM/NWSIWX WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1252 PM CDT SAT MAR 29 2014 .SYNOPSIS... ISSUED AT 324 AM CDT SAT MAR 29 2014 AN UPPER LEVEL SHORTWAVE WITH SEVERAL EMBEDDED COMPACT VORT MAXIMA WAS EVIDENT ON SATELLITE WV IMAGES MOVING THROUGH CENTRAL IA AND WESTERN MO AT 07Z. AREA RADARS INDICATED A FEW WEAK ECHOES IN THE LIFT AHEAD OF THIS FEATURE FROM SW WI ALONG THE MS RIVER TO W CENTRAL IL. AREA OBSERVATIONS HAVE YET TO INDICATE ANY PRECIPITATION REACHING THE GROUND FROM THESE WEAK RETURNS. AN INVERTED TROUGH AT THE SURFACE...REACHING FROM THE CENTRAL IL INTO EAST CENTRAL IA...WAS PROVIDING ENOUGH LOW LEVEL CONVERGENCE TO KEEP THE WIDESPREAD STRATUS THAT NEVER LEFT THE AREA YESTERDAY IN PLACE. THE 00Z KDVN SOUNDING SHOWED AN ASSOCIATED SHALLOW LAYER OF MOISTURE TRAPPED JUST BELOW AN INVERSION AND WEDGE OF DRY AIR ABOVE 900 MB. UPSTREAM...A LARGE UPPER LOW WAS OFF THE BC COAST WITH A DOWNSTREAM RIDGE AXIS MOVING THROUGH THE NORTHERN ROCKIES. AHEAD OF THIS UPPER RIDGE...HIGH PRESSURE AT THE SURFACE REACHED FROM NEB INTO NORTHERN MN. UNDER THIS RIDGE...SKIES WERE MAINLY CLEAR AND THE MUCH DRIER AIRMASS FEATURED DEWPOINTS IN THE TEENS AND 20S...CONTRASTING TO THE UPPER 20S TO LOWER 30S CURRENTLY OVER THE FORECAST AREA. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 324 AM CDT SAT MAR 29 2014 MAIN CHALLENGE CENTERS ON HOW FAST CLOUDS WILL CLEAR TODAY AND THE IMPACT ON TEMPERATURES IN THE SHORT TERM. THE ADVANCING UPSTREAM UPPER RIDGE AND DEEPENING AND PHASING OF THE DOWNSTREAM TROUGH OVER THE OHIO VALLEY TODAY WILL RESULT IN A DEVELOPING MORE FAVORABLE SUBSIDENCE REGIME THAN YESTERDAY. HOWEVER...THIS APPEARS TO BE A SLOW PROCESS...AND MAY NOT RESULT IN ANY SIGNIFICANT CLEARING UNTIL AFTERNOON. AT THE SURFACE...A DEEPENING LOW PRESSURE SYSTEM RIDING NORTHEAST THROUGH KY AND TN WILL IS SHOWN KEEPING AT LEAST A WEAK CYCLONIC CURVATURE IN THE SURFACE PRESSURE FIELD EXTENDING NORTHEAST INTO EASTERN IA UNTIL MIDDAY. THE ASSOCIATED WEAK LOW LEVEL CONVERGENCE AND TRAPPED MOISTURE BELOW THE LINGERING INVERSION ALOFT...WILL KEEP THE STRATUS HOLDING IN PLACE OVER MOST THE FORECAST AREA THIS MORNING. THE BACK EDGE OF THE CLOUDS...CURRENTLY SLOWLY ADVANCING E-SE ACROSS N CENTRAL AND FAR WESTERN IA WILL LIKELY COME TO A HALT OVER CENTRAL IA INTO EASTERN IA THIS MORNING. FORECAST MODELS CONTINUE TO STRUGGLE WITH THIS...AND AT THIS TIME ONLY THE RAP 900 MB RH FIELD SEEMS TO HAVE A GOOD HANDLE ON THIS TREND. WILL THUS KEEP MOSTLY CLOUDY SKIES GOING THROUGH THE MORNING...THEN TRANSITION TO MOSTLY SUNNY BY AFTERNOON AS THE SURFACE AND UPPER LEVEL RIDGE MOVE OVERHEAD BRINGING SUBSIDENCE AND DRIER AIR. ACCOUNTING FOR THIS DELAYED WARMING...AND WEAK MIXING UNDER THE RIDGE...HAVE HELD HIGH TEMPERATURES AT THE LOWER END OF GUIDANCE...FROM THE MID 40S NORTH TO LOWER 50S SOUTH. TONIGHT...SKIES WILL START OUT CLEAR WITH ADVANCING HIGH CLOUDS FOLLOWING PASSAGE OF THE UPPER RIDGE AXIS TOWARD MORNING. AT THE SURFACE... INITIALLY LIGHT WINDS WILL TURN SOUTHERLY AND INCREASE TO AT LEAST 5 TO 10 KTS TOWARD MORNING AS A TROUGH MOVES INTO THE PLAINS. THIS WOULD SUPPORT AN INITIAL COOL-DOWN AFTER SUNSET...THEN STEADY TO POSSIBLY EVEN RISING TEMPERATURES TOWARD SUNRISE. WITH MOST MODELS OVERALL TRENDING TOO MOIST IN THE LOWER LEVELS...HAVE GONE CLOSER TO THE BETTER INITIALIZING ECMWF WITH ITS LOWER DEWPOINTS IN THE 20S BEFORE THE RETURN FLOW SETS UP. THIS POINTS TOWARD LOWER MINS THAN MOS...AND HAVE GONE WITH LOWS FROM THE MID 20S EAST TO LOWER 30S IN THE FAR SOUTHWEST. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 324 AM CDT SAT MAR 29 2014 MILD WITH A FAST MOVING DISTURBANCE MONDAY...THEN FAVORABLE SETUP FOR SIGNIFICANT TO HEAVY PRECIPITATION MID TO LATE NEXT WEEK. OVERVIEW...INITIALIZATION AND VERIFICATION AVERAGE WITH STILL QUESTIONS ON PHASING OF PACIFIC ENERGY ARRIVING NEXT FEW DAYS. AGAIN POOR BL ISSUES THAT ARE OFF BY 3-5 DEGREES FOR BOTH T AND T/D THAT MOS OR OTHER ALGORITHMS ARE HAVING PROBLEMS HANDLING. TREND IS FOR A DEEPER TROUGH INTO THE PACIFIC SW BY TUESDAY WHICH IS A GOOD REGIME FOR MODERATE TO HEAVY PRECIPITATION...MOSTLY RAIN WITH STALLED FRONT TO OUR SOUTH FOR PROLONGED UPGLIDE. VARIANCES CONTINUE WITH HI-RES ECMWF BY FAR THE FURTHEST NORTH. RUN TO RUN TRENDS AND VARIANCES SUPPORTS A MIX OF THE UKMET/GFS /GEM-NH AND TO DISREGARD THE HI-RES ECMWF. TRENDS ARE FOR NORTH PORTIONS TO SEE AT LEAST A FEW PERIODS OF A MIX OF RAIN AND WET SNOW WHICH WILL TAKE ANOTHER 24 HOURS TO BETTER ASCERTAIN. THIS 2 TO 3 DAY EVENT WEDNESDAY INTO FRIDAY WILL BE THE HEAVIEST PRECIPITATION EVENT...WIDESPREAD 1 TO 2 PLUS INCH AMOUNTS SINCE LAST FALL. CONDITIONS OF THIS TYPE CONTINUE TO SUGGEST WILL HELP REPLENISH THE MODESTLY DRY SOILS AND PREPARE THE GROUND FOR SPRING. SUNDAY...EXPECT MODERATE BL MIXING AND MODERATE SOUTHERLY WINDS OF UP TO 15 TO 25+ PH IN THE AFTERNOON. TRENDS STILL SUPPORT HIGHS IN LOWER TO MIDDLE 60S WITH AFTERNOON RH VALUES FALLING BELOW 50 PERCENT TO LOCALLY NEAR 40 PERCENT. THIS INDICATES GFDI VALUES INTO VERY HIGH CATEGORY FOR SEVERAL HOURS IN THE AFTERNOON...MAINLY WEST OF THE MISSISSIPPI RIVER DUE TO LITTLE TO NO GREENING OF VEGETATION. THIS WILL REMAIN IN THE HWO PRODUCT. SUNDAY NIGHT...SOUTH WINDS OF 10 TO 20 MPH TO MAKE FOR THE MILDEST NIGHT IN MANY MONTHS DESPITE FAIR SKIES WITH LOWS IN THE MID TO UPPER 40S....TO AROUND 50F SOUTH. MONDAY...NEXT VIGOROUS AND FAST MOVING STORM SYSTEM SIMILAR TO YESTERDAY/S. IS SLIGHTLY SLOWER...KEEPING MID CHANCE POPS WITH SHOWERS AND ISOLATED MAINLY PM STORMS. WINDS WILL BE STRONGER ALLOWING FOR LOWER PM DEWPOINTS. MID LEVEL SHOWERS AND ISOLATED STORMS WITH BASES AOA 6K AGL. LOW FREEZING LEVEL STILL SUGGESTS NON-SEVERE STORMS WITH SOME PEA HAIL POSSIBLE AS ANY STORMS WOULD FIRE OVER CWA IN MID/LATE PM HOURS. RAISED HIGHS BY 2-3 DEGREES INTO THE MID/UPPER 60S. WINDS MID DAY SHOULD BECOME QUITE WINDY APPROACHING WIND ADVISORY CRITERIA OF 20 TO 30 MPH WITH GUSTS TO AROUND 40 MPH. RH VALUES SHOULD FALL TO AROUND 50 PERCENT THAT MAY SUPPORT NEAR VERY HIGH CONDITIONS FOR FIRE WEATHER BUT SHOWERS/STORMS SHOULD AMELIORATE A BIT ALONG WITH HIGHER RH VALUES. MONDAY NIGHT...SLIGHTLY DELAYED TIMING OF COOL FRONTAL PASSAGE INTO MID/LATE EVENING AND GUSTY NW WINDS TO LIMIT COOLING BY MORNING. THIS SUGGESTS MINS NEAR GUIDANCE BLEND...OR UPPER 20S FAR NW TO MIDDLE 30S FAR SE SECTIONS. TUESDAY...LITTLE CHANGE TO CURRENT FORECAST. COOLER AND MOSTLY FAIR SKIES WITH HIGHS MOSTLY OF 45 TO 50 DEGREES AND LIGHT NE WINDS AHEAD OF NEXT...LARGE...SLOW MOVING AND QUITE STRONG UPPER DISTURBANCE AND DEEP TROUGH MOVING EAST FROM CALIFORNIA. TUESDAY NIGHT...INCREASING CLOUDS STILL SUGGEST LOWS TO OCCUR NEAR OR BEFORE MIDNIGHT....THEN RISING TOWARD MORNING WITH CLOUDS RAIN AND INCREASING EAST WINDS. LOCATIONS NORTH OF I-80 MAY SEE WITH EVAPORATIVE COOLING A MIX OF SNOW BY MORNING...OR JUST A WET SNOW. THIS REMAINS A POOR CONFIDENCE ON MIXED PRECIPITATION NORTH SECTIONS. THIS QUESTION SHOULD BE RESOLVED NEXT 12-24 HOURS. LOCAL TOOLS DO SUPPORT SOME ACCUMULATIONS MAY OCCUR ON EXPOSED SURFACES ATTM BUT AREA TEMPERATURES AT OR SLIGHTLY ABOVE FREEZING TO LIMIT IMPACTS ON ROADWAYS. WEDNESDAY THROUGH FRIDAY...PROLONGED PERIODS OF CLOUDY...COLD AND EPISODES OF RAIN OR MOSTLY RAIN WITH A RISK OF A MIX NORTH SECTIONS OR EVEN A WET SNOW BY FRIDAY AS SYSTEM MOVES EAST. HIGHS MOSTLY IN THE 40S WITH LOWS IN THE 30S. REVIEW OF LOCAL FORECAST AREA TOOLS INDICATE 1 TO LOCALLY NEAR 2 INCHES OF RAIN OR MOSTLY RAIN OVER THIS PERIOD REMAINS ON TRACK. THIS SYSTEM IS SLOWING DOWN WHICH MAY ALLOW FOR EVEN MORE MOISTURE AND MAY RESULT IN EVEN SLIGHTLY HEAVIER AMOUNTS OF RAIN AND EVEN A WET SNOW AS OPEN GULF MOISTURE HAS MORE TIME TO POOL AHEAD OF THE FRONT. THIS SYSTEM BEARS CLOSE WATCHING DUE TO ITS STRENGTH...CURRENT TRACK TO THE FORECAST AREA. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 1240 PM CDT SAT MAR 29 2014 HIGH PRESSURE OVER WESTERN IOWA WILL MOVE EAST AND SHOULD BE OVER EASTERN IL BY SUNDAY MORNING. LOW PRESSURE WILL DEVELOP OVER THE CENTRAL HIGH PLAINS TONIGHT. AN AREA STRATUS WITH BASES IN THE 2 TO 3KFT RANGE WAS OVER SOUTHEAST IOWA AND ADJOINING AREAS OF MISSOURI AND ILLINOIS. THE STRATUS WAS MOVING SOUTH AND SHOULD MOVE OUT OF THE AREA EARLY THIS AFTERNOON. A NARROW BAND OF CU WITH BASES MAINLY ABOVE 3KFT WAS ALSO LOCATED OVER EASTERN IOWA FROM WEST OF KDBQ SOUTH THROUGH KFFL AND WAS SUPPORTED BY WEAK LOW LEVEL CONVERGENCE. AS THE HIGH PRESSURE BUILDS IN AND WITH LOSS OF HEATING LATE THIS AFTERNOON THE CU SHOULD DISSIPATE. FOR THE OVERNIGHT HOURS VFR CONDITIONS WITH LIGHT WINDS VEERING TO THE SOUTHEAST ARE EXPECTED. MID-MORNING SUNDAY GUSTY SOUTH WINDS ARE EXPECTED TO DEVELOP OVER EASTERN IOWA. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...NONE. IL...NONE. MO...NONE. && $$ SYNOPSIS...SHEETS SHORT TERM...SHEETS LONG TERM...NICHOLS AVIATION...DLF
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
645 AM CDT SAT MAR 29 2014 .SYNOPSIS... ISSUED AT 324 AM CDT SAT MAR 29 2014 AN UPPER LEVEL SHORTWAVE WITH SEVERAL EMBEDDED COMPACT VORT MAXIMA WAS EVIDENT ON SATELLITE WV IMAGES MOVING THROUGH CENTRAL IA AND WESTERN MO AT 07Z. AREA RADARS INDICATED A FEW WEAK ECHOES IN THE LIFT AHEAD OF THIS FEATURE FROM SW WI ALONG THE MS RIVER TO W CENTRAL IL. AREA OBSERVATIONS HAVE YET TO INDICATE ANY PRECIPITATION REACHING THE GROUND FROM THESE WEAK RETURNS. AN INVERTED TROUGH AT THE SURFACE...REACHING FROM THE CENTRAL IL INTO EAST CENTRAL IA...WAS PROVIDING ENOUGH LOW LEVEL CONVERGENCE TO KEEP THE WIDESPREAD STRATUS THAT NEVER LEFT THE AREA YESTERDAY IN PLACE. THE 00Z KDVN SOUNDING SHOWED AN ASSOCIATED SHALLOW LAYER OF MOISTURE TRAPPED JUST BELOW AN INVERSION AND WEDGE OF DRY AIR ABOVE 900 MB. UPSTREAM...A LARGE UPPER LOW WAS OFF THE BC COAST WITH A DOWNSTREAM RIDGE AXIS MOVING THROUGH THE NORTHERN ROCKIES. AHEAD OF THIS UPPER RIDGE...HIGH PRESSURE AT THE SURFACE REACHED FROM NEB INTO NORTHERN MN. UNDER THIS RIDGE...SKIES WERE MAINLY CLEAR AND THE MUCH DRIER AIRMASS FEATURED DEWPOINTS IN THE TEENS AND 20S...CONTRASTING TO THE UPPER 20S TO LOWER 30S CURRENTLY OVER THE FORECAST AREA. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 324 AM CDT SAT MAR 29 2014 MAIN CHALLENGE CENTERS ON HOW FAST CLOUDS WILL CLEAR TODAY AND THE IMPACT ON TEMPERATURES IN THE SHORT TERM. THE ADVANCING UPSTREAM UPPER RIDGE AND DEEPENING AND PHASING OF THE DOWNSTREAM TROUGH OVER THE OHIO VALLEY TODAY WILL RESULT IN A DEVELOPING MORE FAVORABLE SUBSIDENCE REGIME THAN YESTERDAY. HOWEVER...THIS APPEARS TO BE A SLOW PROCESS...AND MAY NOT RESULT IN ANY SIGNIFICANT CLEARING UNTIL AFTERNOON. AT THE SURFACE...A DEEPENING LOW PRESSURE SYSTEM RIDING NORTHEAST THROUGH KY AND TN WILL IS SHOWN KEEPING AT LEAST A WEAK CYCLONIC CURVATURE IN THE SURFACE PRESSURE FIELD EXTENDING NORTHEAST INTO EASTERN IA UNTIL MIDDAY. THE ASSOCIATED WEAK LOW LEVEL CONVERGENCE AND TRAPPED MOISTURE BELOW THE LINGERING INVERSION ALOFT...WILL KEEP THE STRATUS HOLDING IN PLACE OVER MOST THE FORECAST AREA THIS MORNING. THE BACK EDGE OF THE CLOUDS...CURRENTLY SLOWLY ADVANCING E-SE ACROSS N CENTRAL AND FAR WESTERN IA WILL LIKELY COME TO A HALT OVER CENTRAL IA INTO EASTERN IA THIS MORNING. FORECAST MODELS CONTINUE TO STRUGGLE WITH THIS...AND AT THIS TIME ONLY THE RAP 900 MB RH FIELD SEEMS TO HAVE A GOOD HANDLE ON THIS TREND. WILL THUS KEEP MOSTLY CLOUDY SKIES GOING THROUGH THE MORNING...THEN TRANSITION TO MOSTLY SUNNY BY AFTERNOON AS THE SURFACE AND UPPER LEVEL RIDGE MOVE OVERHEAD BRINGING SUBSIDENCE AND DRIER AIR. ACCOUNTING FOR THIS DELAYED WARMING...AND WEAK MIXING UNDER THE RIDGE...HAVE HELD HIGH TEMPERATURES AT THE LOWER END OF GUIDANCE...FROM THE MID 40S NORTH TO LOWER 50S SOUTH. TONIGHT...SKIES WILL START OUT CLEAR WITH ADVANCING HIGH CLOUDS FOLLOWING PASSAGE OF THE UPPER RIDGE AXIS TOWARD MORNING. AT THE SURFACE... INITIALLY LIGHT WINDS WILL TURN SOUTHERLY AND INCREASE TO AT LEAST 5 TO 10 KTS TOWARD MORNING AS A TROUGH MOVES INTO THE PLAINS. THIS WOULD SUPPORT AN INITIAL COOL-DOWN AFTER SUNSET...THEN STEADY TO POSSIBLY EVEN RISING TEMPERATURES TOWARD SUNRISE. WITH MOST MODELS OVERALL TRENDING TOO MOIST IN THE LOWER LEVELS...HAVE GONE CLOSER TO THE BETTER INITIALIZING ECMWF WITH ITS LOWER DEWPOINTS IN THE 20S BEFORE THE RETURN FLOW SETS UP. THIS POINTS TOWARD LOWER MINS THAN MOS...AND HAVE GONE WITH LOWS FROM THE MID 20S EAST TO LOWER 30S IN THE FAR SOUTHWEST. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 324 AM CDT SAT MAR 29 2014 MILD WITH A FAST MOVING DISTURBANCE MONDAY...THEN FAVORABLE SETUP FOR SIGNIFICANT TO HEAVY PRECIPITATION MID TO LATE NEXT WEEK. OVERVIEW...INITIALIZATION AND VERIFICATION AVERAGE WITH STILL QUESTIONS ON PHASING OF PACIFIC ENERGY ARRIVING NEXT FEW DAYS. AGAIN POOR BL ISSUES THAT ARE OFF BY 3-5 DEGREES FOR BOTH T AND T/D THAT MOS OR OTHER ALGORITHMS ARE HAVING PROBLEMS HANDLING. TREND IS FOR A DEEPER TROUGH INTO THE PACIFIC SW BY TUESDAY WHICH IS A GOOD REGIME FOR MODERATE TO HEAVY PRECIPITATION...MOSTLY RAIN WITH STALLED FRONT TO OUR SOUTH FOR PROLONGED UPGLIDE. VARIANCES CONTINUE WITH HI-RES ECMWF BY FAR THE FURTHEST NORTH. RUN TO RUN TRENDS AND VARIANCES SUPPORTS A MIX OF THE UKMET/GFS /GEM-NH AND TO DISREGARD THE HI-RES ECMWF. TRENDS ARE FOR NORTH PORTIONS TO SEE AT LEAST A FEW PERIODS OF A MIX OF RAIN AND WET SNOW WHICH WILL TAKE ANOTHER 24 HOURS TO BETTER ASCERTAIN. THIS 2 TO 3 DAY EVENT WEDNESDAY INTO FRIDAY WILL BE THE HEAVIEST PRECIPITATION EVENT...WIDESPREAD 1 TO 2 PLUS INCH AMOUNTS SINCE LAST FALL. CONDITIONS OF THIS TYPE CONTINUE TO SUGGEST WILL HELP REPLENISH THE MODESTLY DRY SOILS AND PREPARE THE GROUND FOR SPRING. SUNDAY...EXPECT MODERATE BL MIXING AND MODERATE SOUTHERLY WINDS OF UP TO 15 TO 25+ PH IN THE AFTERNOON. TRENDS STILL SUPPORT HIGHS IN LOWER TO MIDDLE 60S WITH AFTERNOON RH VALUES FALLING BELOW 50 PERCENT TO LOCALLY NEAR 40 PERCENT. THIS INDICATES GFDI VALUES INTO VERY HIGH CATEGORY FOR SEVERAL HOURS IN THE AFTERNOON...MAINLY WEST OF THE MISSISSIPPI RIVER DUE TO LITTLE TO NO GREENING OF VEGETATION. THIS WILL REMAIN IN THE HWO PRODUCT. SUNDAY NIGHT...SOUTH WINDS OF 10 TO 20 MPH TO MAKE FOR THE MILDEST NIGHT IN MANY MONTHS DESPITE FAIR SKIES WITH LOWS IN THE MID TO UPPER 40S....TO AROUND 50F SOUTH. MONDAY...NEXT VIGOROUS AND FAST MOVING STORM SYSTEM SIMILAR TO YESTERDAY/S. IS SLIGHTLY SLOWER...KEEPING MID CHANCE POPS WITH SHOWERS AND ISOLATED MAINLY PM STORMS. WINDS WILL BE STRONGER ALLOWING FOR LOWER PM DEWPOINTS. MID LEVEL SHOWERS AND ISOLATED STORMS WITH BASES AOA 6K AGL. LOW FREEZING LEVEL STILL SUGGESTS NON-SEVERE STORMS WITH SOME PEA HAIL POSSIBLE AS ANY STORMS WOULD FIRE OVER CWA IN MID/LATE PM HOURS. RAISED HIGHS BY 2-3 DEGREES INTO THE MID/UPPER 60S. WINDS MID DAY SHOULD BECOME QUITE WINDY APPROACHING WIND ADVISORY CRITERIA OF 20 TO 30 MPH WITH GUSTS TO AROUND 40 MPH. RH VALUES SHOULD FALL TO AROUND 50 PERCENT THAT MAY SUPPORT NEAR VERY HIGH CONDITIONS FOR FIRE WEATHER BUT SHOWERS/STORMS SHOULD AMELIORATE A BIT ALONG WITH HIGHER RH VALUES. MONDAY NIGHT...SLIGHTLY DELAYED TIMING OF COOL FRONTAL PASSAGE INTO MID/LATE EVENING AND GUSTY NW WINDS TO LIMIT COOLING BY MORNING. THIS SUGGESTS MINS NEAR GUIDANCE BLEND...OR UPPER 20S FAR NW TO MIDDLE 30S FAR SE SECTIONS. TUESDAY...LITTLE CHANGE TO CURRENT FORECAST. COOLER AND MOSTLY FAIR SKIES WITH HIGHS MOSTLY OF 45 TO 50 DEGREES AND LIGHT NE WINDS AHEAD OF NEXT...LARGE...SLOW MOVING AND QUITE STRONG UPPER DISTURBANCE AND DEEP TROUGH MOVING EAST FROM CALIFORNIA. TUESDAY NIGHT...INCREASING CLOUDS STILL SUGGEST LOWS TO OCCUR NEAR OR BEFORE MIDNIGHT....THEN RISING TOWARD MORNING WITH CLOUDS RAIN AND INCREASING EAST WINDS. LOCATIONS NORTH OF I-80 MAY SEE WITH EVAPORATIVE COOLING A MIX OF SNOW BY MORNING...OR JUST A WET SNOW. THIS REMAINS A POOR CONFIDENCE ON MIXED PRECIPITATION NORTH SECTIONS. THIS QUESTION SHOULD BE RESOLVED NEXT 12-24 HOURS. LOCAL TOOLS DO SUPPORT SOME ACCUMULATIONS MAY OCCUR ON EXPOSED SURFACES ATTM BUT AREA TEMPERATURES AT OR SLIGHTLY ABOVE FREEZING TO LIMIT IMPACTS ON ROADWAYS. WEDNESDAY THROUGH FRIDAY...PROLONGED PERIODS OF CLOUDY...COLD AND EPISODES OF RAIN OR MOSTLY RAIN WITH A RISK OF A MIX NORTH SECTIONS OR EVEN A WET SNOW BY FRIDAY AS SYSTEM MOVES EAST. HIGHS MOSTLY IN THE 40S WITH LOWS IN THE 30S. REVIEW OF LOCAL FORECAST AREA TOOLS INDICATE 1 TO LOCALLY NEAR 2 INCHES OF RAIN OR MOSTLY RAIN OVER THIS PERIOD REMAINS ON TRACK. THIS SYSTEM IS SLOWING DOWN WHICH MAY ALLOW FOR EVEN MORE MOISTURE AND MAY RESULT IN EVEN SLIGHTLY HEAVIER AMOUNTS OF RAIN AND EVEN A WET SNOW AS OPEN GULF MOISTURE HAS MORE TIME TO POOL AHEAD OF THE FRONT. THIS SYSTEM BEARS CLOSE WATCHING DUE TO ITS STRENGTH...CURRENT TRACK TO THE FORECAST AREA. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 645 AM CDT SAT MAR 29 2014 LOW CLOUDS COVERING EASTERN IOWA AND NORTHWEST ILLINOIS EARLY THIS MORNING WILL GRADUALLY DISSIPATE AND PUSH EASTWARD TODAY AS HIGH PRESSURE MOVES INTO THE REGION. THERE REMAINS CONSIDERABLE UNCERTAINTY IN THE TIMING OF THIS CLEARING. TEMPO GROUPS WERE UTILIZED IN THE TAFS TO DEMONSTRATE THIS UNCERTAIN LATE MORNING TRANSITION FROM MVFR TO VFR CONDITIONS AT DBQ...MLI AND BRL. HIGH PRESSURE WILL THEN PROVIDE LIGHT WINDS AND VFR CONDITIONS OVERNIGHT. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...NONE. IL...NONE. MO...NONE. && $$ SYNOPSIS...SHEETS SHORT TERM...SHEETS LONG TERM...NICHOLS AVIATION...SHEETS
AREA FORECAST DISCUSSION...CORRECTED TYPO
NWS QUAD CITIES IA IL
425 AM CDT SAT MAR 29 2014 .SYNOPSIS... ISSUED AT 240 AM CDT SAT MAR 29 2014 AN UPPER LEVEL SHORTWAVE WITH SEVERAL EMBEDDED COMPACT VORT MAXIMA WAS EVIDENT ON SATELLITE WV IMAGES MOVING THROUGH CENTRAL IA AND WESTERN MO AT 07Z. AREA RADARS INDICATED A FEW WEAK ECHOES IN THE LIFT AHEAD OF THIS FEATURE FROM SW WI ALONG THE MS RIVER TO W CENTRAL IL. AREA OBSERVATIONS HAVE YET TO INDICATE ANY PRECIPITATION REACHING THE GROUND FROM THESE WEAK RETURNS. AN INVERTED TROUGH AT THE SURFACE...REACHING FROM THE CENTRAL IL INTO EAST CENTRAL IA...WAS PROVIDING ENOUGH LOW LEVEL CONVERGENCE TO KEEP THE WIDESPREAD STRATUS THAT NEVER LEFT THE AREA YESTERDAY IN PLACE. THE 00Z KDVN SOUNDING SHOWED AN ASSOCIATED SHALLOW LAYER OF MOISTURE TRAPPED JUST BELOW AN INVERSION AND WEDGE OF DRY AIR ABOVE 900 MB. UPSTREAM...A LARGE UPPER LOW WAS OFF THE BC COAST WITH A DOWNSTREAM RIDGE AXIS MOVING THROUGH THE NORTHERN ROCKIES. AHEAD OF THIS UPPER RIDGE...HIGH PRESSURE AT THE SURFACE REACHED FROM NEB INTO NORTHERN MN. UNDER THIS RIDGE...SKIES WERE MAINLY CLEAR AND THE MUCH DRIER AIRMASS FEATURED DEWPOINTS IN THE TEENS AND 20S...CONTRASTING TO THE UPPER 20S TO LOWER 30S CURRENTLY OVER THE FORECAST AREA. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 240 AM CDT SAT MAR 29 2014 MAIN CHALLENGE CENTERS ON HOW FAST CLOUDS WILL CLEAR TODAY AND THE IMPACT ON TEMPERATURES IN THE SHORT TERM. THE ADVANCING UPSTREAM UPPER RIDGE AND DEEPENING AND PHASING OF THE DOWNSTREAM TROUGH OVER THE OHIO VALLEY TODAY WILL RESULT IN A DEVELOPING MORE FAVORABLE SUBSIDENCE REGIME THAN YESTERDAY. HOWEVER...THIS APPEARS TO BE A SLOW PROCESS...AND MAY NOT RESULT IN ANY SIGNIFICANT CLEARING UNTIL AFTERNOON. AT THE SURFACE...A DEEPENING LOW PRESSURE SYSTEM RIDING NORTHEAST THROUGH KY AND TN WILL IS SHOWN KEEPING AT LEAST A WEAK CYCLONIC CURVATURE IN THE SURFACE PRESSURE FIELD EXTENDING NORTHEAST INTO EASTERN IA UNTIL MIDDAY. THE ASSOCIATED WEAK LOW LEVEL CONVERGENCE AND TRAPPED MOISTURE BELOW THE LINGERING INVERSION ALOFT...WILL KEEP THE STRATUS HOLDING IN PLACE OVER MOST THE FORECAST AREA THIS MORNING. THE BACK EDGE OF THE CLOUDS...CURRENTLY SLOWLY ADVANCING E-SE ACROSS N CENTRAL AND FAR WESTERN IA WILL LIKELY COME TO A HALT OVER CENTRAL IA INTO EASTERN IA THIS MORNING. FORECAST MODELS CONTINUE TO STRUGGLE WITH THIS...AND AT THIS TIME ONLY THE RAP 900 MB RH FIELD SEEMS TO HAVE A GOOD HANDLE ON THIS TREND. WILL THUS KEEP MOSTLY CLOUDY SKIES GOING THROUGH THE MORNING...THEN TRANSITION TO MOSTLY SUNNY BY AFTERNOON AS THE SURFACE AND UPPER LEVEL RIDGE MOVE OVERHEAD BRINGING SUBSIDENCE AND DRIER AIR. ACCOUNTING FOR THIS DELAYED WARMING...AND WEAK MIXING UNDER THE RIDGE...HAVE HELD HIGH TEMPERATURES AT THE LOWER END OF GUIDANCE...FROM THE MID 40S NORTH TO LOWER 50S SOUTH. TONIGHT...SKIES WILL START OUT CLEAR WITH ADVANCING HIGH CLOUDS FOLLOWING PASSAGE OF THE UPPER RIDGE AXIS TOWARD MORNING. AT THE SURFACE... INITIALLY LIGHT WINDS WILL TURN SOUTHERLY AND INCREASE TO AT LEAST 5 TO 10 KTS TOWARD MORNING AS A TROUGH MOVES INTO THE PLAINS. THIS WOULD SUPPORT AN INITIAL COOL-DOWN AFTER SUNSET...THEN STEADY TO POSSIBLY EVEN RISING TEMPERATURES TOWARD SUNRISE. WITH MOST MODELS OVERALL TRENDING TOO MOIST IN THE LOWER LEVELS...HAVE GONE CLOSER TO THE BETTER INITIALIZING ECMWF WITH ITS LOWER DEWPOINTS IN THE 20S BEFORE THE RETURN FLOW SETS UP. THIS POINTS TOWARD LOWER MINS THAN MOS...AND HAVE GONE WITH LOWS FROM THE MID 20S EAST TO LOWER 30S IN THE FAR SOUTHWEST. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 240 AM CDT SAT MAR 29 2014 MILD WITH A FAST MOVING DISTURBANCE MONDAY...THEN FAVORABLE SETUP FOR SIGNIFICANT TO HEAVY PRECIPITATION MID TO LATE NEXT WEEK. OVERVIEW...INITIALIZATION AND VERIFICATION AVERAGE WITH STILL QUESTIONS ON PHASING OF PACIFIC ENERGY ARRIVING NEXT FEW DAYS. AGAIN POOR BL ISSUES THAT ARE OFF BY 3-5 DEGREES FOR BOTH T AND T/D THAT MOS OR OTHER ALGORITHMS ARE HAVING PROBLEMS HANDLING. TREND IS FOR A DEEPER TROUGH INTO THE PACIFIC SW BY TUESDAY WHICH IS A GOOD REGIME FOR MODERATE TO HEAVY PRECIPITATION...MOSTLY RAIN WITH STALLED FRONT TO OUR SOUTH FOR PROLONGED UPGLIDE. VARIANCES CONTINUE WITH HI-RES ECMWF BY FAR THE FURTHEST NORTH. RUN TO RUN TRENDS AND VARIANCES SUPPORTS A MIX OF THE UKMET/GFS /GEM-NH AND TO DISREGARD THE HI-RES ECMWF. TRENDS ARE FOR NORTH PORTIONS TO SEE AT LEAST A FEW PERIODS OF A MIX OF RAIN AND WET SNOW WHICH WILL TAKE ANOTHER 24 HOURS TO BETTER ASCERTAIN. THIS 2 TO 3 DAY EVENT WEDNESDAY INTO FRIDAY WILL BE THE HEAVIEST PRECIPITATION EVENT...WIDESPREAD 1 TO 2 PLUS INCH AMOUNTS SINCE LAST FALL. CONDITIONS OF THIS TYPE CONTINUE TO SUGGEST WILL HELP REPLENISH THE MODESTLY DRY SOILS AND PREPARE THE GROUND FOR SPRING. SUNDAY...EXPECT MODERATE BL MIXING AND MODERATE SOUTHERLY WINDS OF UP TO 15 TO 25+ PH IN THE AFTERNOON. TRENDS STILL SUPPORT HIGHS IN LOWER TO MIDDLE 60S WITH AFTERNOON RH VALUES FALLING BELOW 50 PERCENT TO LOCALLY NEAR 40 PERCENT. THIS INDICATES GFDI VALUES INTO VERY HIGH CATEGORY FOR SEVERAL HOURS IN THE AFTERNOON...MAINLY WEST OF THE MISSISSIPPI RIVER DUE TO LITTLE TO NO GREENING OF VEGETATION. THIS WILL REMAIN IN THE HWO PRODUCT. SUNDAY NIGHT...SOUTH WINDS OF 10 TO 20 MPH TO MAKE FOR THE MILDEST NIGHT IN MANY MONTHS DESPITE FAIR SKIES WITH LOWS IN THE MID TO UPPER 40S....TO AROUND 50F SOUTH. MONDAY...NEXT VIGOROUS AND FAST MOVING STORM SYSTEM SIMILAR TO YESTERDAY/S. IS SLIGHTLY SLOWER...KEEPING MID CHANCE POPS WITH SHOWERS AND ISOLATED MAINLY PM STORMS. WINDS WILL BE STRONGER ALLOWING FOR LOWER PM DEWPOINTS. MID LEVEL SHOWERS AND ISOLATED STORMS WITH BASES AOA 6K AGL. LOW FREEZING LEVEL STILL SUGGESTS NON-SEVERE STORMS WITH SOME PEA HAIL POSSIBLE AS ANY STORMS WOULD FIRE OVER CWA IN MID/LATE PM HOURS. RAISED HIGHS BY 2-3 DEGREES INTO THE MID/UPPER 60S. WINDS MID DAY SHOULD BECOME QUITE WINDY APPROACHING WIND ADVISORY CRITERIA OF 20 TO 30 MPH WITH GUSTS TO AROUND 40 MPH. RH VALUES SHOULD FALL TO AROUND 50 PERCENT THAT MAY SUPPORT NEAR VERY HIGH CONDITIONS FOR FIRE WEATHER BUT SHOWERS/STORMS SHOULD AMELIORATE A BIT ALONG WITH HIGHER RH VALUES. MONDAY NIGHT...SLIGHTLY DELAYED TIMING OF COOL FRONTAL PASSAGE INTO MID/LATE EVENING AND GUSTY NW WINDS TO LIMIT COOLING BY MORNING. THIS SUGGESTS MINS NEAR GUIDANCE BLEND...OR UPPER 20S FAR NW TO MIDDLE 30S FAR SE SECTIONS. TUESDAY...LITTLE CHANGE TO CURRENT FORECAST. COOLER AND MOSTLY FAIR SKIES WITH HIGHS MOSTLY OF 45 TO 50 DEGREES AND LIGHT NE WINDS AHEAD OF NEXT...LARGE...SLOW MOVING AND QUITE STRONG UPPER DISTURBANCE AND DEEP TROUGH MOVING EAST FROM CALIFORNIA. TUESDAY NIGHT...INCREASING CLOUDS STILL SUGGEST LOWS TO OCCUR NEAR OR BEFORE MIDNIGHT....THEN RISING TOWARD MORNING WITH CLOUDS RAIN AND INCREASING EAST WINDS. LOCATIONS NORTH OF I-80 MAY SEE WITH EVAPORATIVE COOLING A MIX OF SNOW BY MORNING...OR JUST A WET SNOW. THIS REMAINS A POOR CONFIDENCE ON MIXED PRECIPITATION NORTH SECTIONS. THIS QUESTION SHOULD BE RESOLVED NEXT 12-24 HOURS. LOCAL TOOLS DO SUPPORT SOME ACCUMULATIONS MAY OCCUR ON EXPOSED SURFACES ATTM BUT AREA TEMPERATURES AT OR SLIGHTLY ABOVE FREEZING TO LIMIT IMPACTS ON ROADWAYS. WEDNESDAY THROUGH FRIDAY...PROLONGED PERIODS OF CLOUDY...COLD AND EPISODES OF RAIN OR MOSTLY RAIN WITH A RISK OF A MIX NORTH SECTIONS OR EVEN A WET SNOW BY FRIDAY AS SYSTEM MOVES EAST. HIGHS MOSTLY IN THE 40S WITH LOWS IN THE 30S. REVIEW OF LOCAL FORECAST AREA TOOLS INDICATE 1 TO LOCALLY NEAR 2 INCHES OF RAIN OR MOSTLY RAIN OVER THIS PERIOD REMAINS ON TRACK. THIS SYSTEM IS SLOWING DOWN WHICH MAY ALLOW FOR EVEN MORE MOISTURE AND MAY RESULT IN EVEN SLIGHTLY HEAVIER AMOUNTS OF RAIN AND EVEN A WET SNOW AS OPEN GULF MOISTURE HAS MORE TIME TO POOL AHEAD OF THE FRONT. THIS SYSTEM BEARS CLOSE WATCHING DUE TO ITS STRENGTH...CURRENT TRACK TO THE FORECAST AREA. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 240 AM CDT SAT MAR 29 2014 STRATUS BASED AROUND 2000 TO 2500 FT AGL WILL CONTINUE TO LINGER OVER ALL OF EASTERN IOWA AND NORTHWEST ILLINOIS THROUGH THE MORNING HOURS. SOME CLEARING IS EXPECTED...BUT MAY TAKE UNTIL 18Z OR EVEN 20Z TO GO SCATTERED OVER LOCATIONS SOUTH OF DBQ ALONG THE MISSISSIPPI RIVER. MLI AND BRL ARE THUS KEPT IN MVFR CONDITIONS THIS MORNING. WINDS WILL OTHERWISE BE VERY LIGHT AND VARIABLE AS HIGH PRESSURE PASSES THROUGH THE AREA. VFR CONDITIONS ARE THEN LIKELY FROM LATE AFTERNOON THROUGH THE OVERNIGHT AT ALL SITES WITH LIGHT WINDS BECOMING SOUTHERLY TOWARD SUNRISE. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...NONE. IL...NONE. MO...NONE. && $$ SYNOPSIS...SHEETS SHORT TERM...SHEETS LONG TERM...NICHOLS AVIATION...SHEETS
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
324 AM CDT SAT MAR 29 2014 .SYNOPSIS... ISSUED AT 240 AM CDT SAT MAR 29 2014 AN UPPER LEVEL SHORTWAVE WITH SEVERAL EMBEDDED COMPACT VORT MAXIMA WAS EVIDENT ON SATELLITE WV IMAGES MOVING THROUGH CENTRAL IA AND WESTERN MO AT 07Z. AREA RADARS INDICATED A FEW WEAK ECHOES IN THE LIFT AHEAD OF THIS FEATURE FROM SW WI ALONG THE MS RIVER TO W CENTRAL IL. AREA OBSERVATIONS HAVE YET TO INDICATE ANY PRECIPITATION REACHING THE GROUND FROM THESE WEAK RETURNS. AN INVERTED TROUGH AT THE SURFACE...REACHING FROM THE CENTRAL IL INTO EAST CENTRAL IA...WAS PROVIDING ENOUGH LOW LEVEL CONVERGENCE TO KEEP THE WIDESPREAD STRATUS THAT NEVER LEFT THE AREA YESTERDAY IN PLACE. THE 00Z KDVN SOUNDING SHOWED AN ASSOCIATED SHALLOW LAYER OF MOISTURE TRAPPED JUST BELOW AN INVERSION AND WEDGE OF DRY AIR ABOVE 900 MB. UPSTREAM...A LARGE UPPER LOW WAS OFF THE BC COAST WITH A DOWNSTREAM RIDGE AXIS MOVING THROUGH THE NORTHERN ROCKIES. AHEAD OF THIS UPPER RIDGE...HIGH PRESSURE AT THE SURFACE REACHED FROM NEB INTO NORTHERN MN. UNDER THIS RIDGE...SKIES WERE MAINLY CLEAR AND THE MUCH DRIER AIRMASS FEATURED DEWPOINTS IN THE TEENS AND 20S...CONTRASTING TO THE UPPER 20S TO LOWER 30S CURRENTLY OVER THE FORECAST AREA. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 240 AM CDT SAT MAR 29 2014 MAIN CHALLENGE CENTERS ON HOW FAST CLOUDS WILL CLEAR TODAY AND THE IMPACT ON TEMPERATURES IN THE SHORT TERM. THE ADVANCING UPSTREAM UPPER RIDGE AND DEEPENING AND PHASING OF THE DOWNSTREAM TROUGH OVER THE OHIO VALLEY TODAY WILL RESULT IN A DEVELOPING MORE FAVORABLE SUBSIDENCE REGIME THAN YESTERDAY. HOWEVER...THIS APPEARS TO BE A SLOW PROCESS...AND MAY NOT RESULT IN ANY SIGNIFICANT CLEARING UNTIL AFTERNOON. AT THE SURFACE...A DEEPENING LOW PRESSURE SYSTEM RIDING NORTHEAST THROUGH KY AND TN WILL IS SHOWN KEEPING AT LEAST A WEAK CYCLONIC CURVATURE IN THE SURFACE PRESSURE FIELD EXTENDING NORTHEAST INTO EASTERN IA UNTIL MIDDAY. THE ASSOCIATED WEAK LOW LEVEL CONVERGENCE AND TRAPPED MOISTURE BELOW THE LINGERING INVERSION ALOFT...WILL KEEP THE STRATUS HOLDING IN PLACE OVER MOST THE FORECAST AREA THIS MORNING. THE BACK EDGE OF THE CLOUDS...CURRENTLY SLOWLY ADVANCING E-SE ACROSS N CENTRAL AND FAR WESTERN IA WILL LIKELY COME TO A HALT OVER CENTRAL IA INTO EASTERN IA THIS MORNING. FORECAST MODELS CONTINUE TO STRUGGLE WITH THIS...AND AT THIS TIME ONLY THE RAP 900 MB RH FIELD SEEMS TO HAVE A GOOD HANDLE ON THIS TREND. WILL THUS KEEP MOSTLY CLOUDY SKIES GOING THROUGH THE MORNING...THEN TRANSITION TO MOSTLY SUNNY BY AFTERNOON AS THE SURFACE AND UPPER LEVEL RIDGE MOVE OVERHEAD BRINGING SUBSIDENCE AND DRIER AIR. ACCOUNTING FOR THIS DELAYED WARMING...AND WEAK MIXING UNDER THE RIDGE...HAVE HELD HIGH TEMPERATURES AT THE LOWER END OF GUIDANCE...FROM THE MID 40S NORTH TO LOWER 50S SOUTH. TONIGHT...SKIES WILL START OUT CLEAR WITH ADVANCING HIGH CLOUDS FOLLOWING PASSAGE OF THE UPPER RIDGE AXIS TOWARD MORNING. AT THE SURFACE... INITIALLY LIGHT WINDS WILL TURN SOUTHERLY AND INCREASE TO AT LEAST 5 TO 10 KTS TOWARD MORNING AS A TROUGH MOVES INTO THE PLAINS. THIS WOULD SUPPORT AN INITIAL COOL-DOWN AFTER SUNSET...THEN STEADY TO POSSIBLY EVEN RISING TEMPERATURES TOWARD SUNRISE. WITH MOST MODELS OVERALL TRENDING TOO MOIST IN THE LOWER LEVELS...HAVE GONE CLOSER TO THE BETTER INITIALIZING ECMWF WITH ITS LOWER DEWPOINTS IN THE 20S BEFORE THE RETURN FLOW SETS UP. THIS POINTS TOWARD LOWER MINS THAN MOS...AND HAVE GONE WITH LOWS FROM THE MID 20S EAST TO LOWER 30S IN THE FAR SOUTHWEST. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 240 AM CDT SAT MAR 29 2014 MILD WITH A FAST MOVING DISTURBANCE MONDAY...THEN FAVORABLE SETUP FOR SIGNIFICANT TO HEAVY PRECIPITATION MID TO LATE NEXT WEEK. OVERVIEW...INITIALIZATION AND VERIFICATION AVERAGE WITH STILL QUESTIONS ON PHASING OF PACIFIC ENERGY ARRIVING NEXT FEW DAYS. AGAIN POOR BL ISSUES THAT ARE OFF BY 3-5 DEGREES FOR BOTH T AND T/D THAT MOS OR OTHER ALGORITHMS ARE HAVING PROBLEMS HANDLING. TREND IS FOR A DEEPER TROUGH INTO THE PACIFIC SW BY TUESDAY WHICH IS A GOOD REGIME FOR MODERATE TO HEAVY PRECIPITATION...MOSTLY RAIN WITH STALLED FRONT TO OUR SOUTH FOR PROLONGED UPGLIDE. VARIANCES CONTINUE WITH HI-RES ECMWF BY FAR THE FURTHEST NORTH. RUN TO RUN TRENDS AND VARIANCES SUPPORTS A MIX OF THE UKMET/GFS /GEM-NH AND TO DISREGARD THE HI-RES ECMWF. TRENDS ARE FOR NORTH PORTIONS TO SEE AT LEAST A FEW PERIODS OF A MIX OF RAIN AND WET SNOW WHICH WILL TAKE ANOTHER 24 HOURS TO BETTER ASCERTAIN. THIS 2 TO 3 DAY EVENT WEDNESDAY INTO FRIDAY WILL BE THE HEAVIEST PRECIPITATION EVENT...WIDESPREAD 1 TO 2 PLUS INCH AMOUNTS SINCE LAST FALL. CONDITIONS OF THIS TYPE CONTINUE TO SUGGEST WILL HELP REPLENISH THE MODESTLY DRY SOILS AND PREPARE THE GROUND FOR SPRING. SUNDAY...EXPECT MODERATE BL MIXING AND MODERATE SOUTHERLY WINDS OF UP TO 15 TO 25+ PH IN THE AFTERNOON. TRENDS STILL SUPPORT HIGHS IN LOWER TO MIDDLE 60S WITH AFTERNOON RH VALUES FALLING BELOW 50 PERCENT TO LOCALLY NEAR 40 PERCENT. THIS INDICATES GFDI VALUES INTO VERY HIGH CATEGORY FOR SEVERAL HOURS IN THE AFTERNOON...MAINLY WEST OF THE MISSISSIPPI RIVER DUE TO LITTLE TO NO GREENING OF VEGETATION. THIS WILL REMAIN IN THE HWO PRODUCT. SUNDAY NIGHT...SOUTH WINDS OF 10 TO 20 MPH TO MAKE FOR THE MILDEST NIGHT IN MANY MONTHS DESPITE FAIR SKIES WITH LOWS IN THE MID TO UPPER 40S....TO AROUND 50F SOUTH. MONDAY...NEXT VIGOROUS AND FAST MOVING STORM SYSTEM SIMILAR TO YESTERDAY/S. IS SLIGHTLY SLOWER...KEEPING MID CHANCE POPS WITH SHOWERS AND ISOLATED MAINLY PM STORMS. WINDS WILL BE STRONGER ALLOWING FOR LOWER PM DEWPOINTS. MID LEVEL SHOWERS AND ISOLATED STORMS WITH BASES AOA 6K AGL. LOW FREEZING LEVEL STILL SUGGESTS NON-SEVERE STORMS WITH SOME PEA HAIL POSSIBLE AS ANY STORMS WOULD FIRE OVER CWA IN MID/LATE PM HOURS. RAISED HIGHS BY 2-3 DEGREES INTO THE MID/UPPER 60S. WINDS MID DAY SHOULD BECOME QUITE WINDY APPROACHING WIND ADVISORY CRITERIA OF 20 TO 30 MPH WITH GUSTS TO AROUND 40 MPH. RH VALUES SHOULD FALL TO AROUND 50 PERCENT THAT MAY SUPPORT NEAR VERY HIGH CONDITIONS FOR FIRE WEATHER BUT SHOWERS/STORMS SHOULD AMELIORATE A BIT ALONG WITH HIGHER RH VALUES. MONDAY NIGHT...SLIGHTLY DELAYED TIMING OF COOL FRONTAL PASSAGE INTO MID/LATE EVENING AND GUSTY NW WINDS TO LIMIT COOLING BY MORNING. THIS SUGGESTS MINS NEAR GUIDANCE BLEND...OR UPPER 20S FAR NW TO MIDDLE 30S FAR SE SECTIONS. TUESDAY...LITTLE CHANGE TO CURRENT FORECAST. COOLER AND MOSTLY FAIR SKIES WITH HIGHS MOSTLY OF 45 TO 50 DEGREES AND LIGHT NE WINDS AHEAD OF NEXT...LARGE...SLOW MOVING AND QUITE STRONG UPPER DISTURBANCE AND DEEP TROUGH MOVING EAST FROM CALIFORNIA. TUESDAY NIGHT...INCREASING CLOUDS STILL SUGGEST LOWS TO OCCUR NEAR OR BEFORE MIDNIGHT....THEN RISING TOWARD MORNING WITH CLOUDS RAIN AND INCREASING EAST WINDS. LOCATIONS NORTH OF I-80 MAY SEE WITH EVAPORATIVE COOLING A MIX OF SNOW BY MORNING...OR JUST A WET SNOW. THIS REMAINS A POOR CONFIDENCE ON MIXED PRECIPITATION NORTH SECTIONS. THIS QUESTION SHOULD BE RESOLVED NEXT 12-24 HOURS. LOCAL TOOLS DO SUPPORT SOME ACCUMULATIONS MAY OCCUR ON EXPOSED SURFACES ATTM BUT AREA TEMPERATURES AT OR SLIGHTLY ABOVE FREEZING TO LIMIT IMPACTS ON ROADWAYS. WEDNESDAY THROUGH FRIDAY...PROLONGED PERIODS OF CLOUDY...COLD AND EPISODES OF RAIN OR MOSTLY RAIN WITH Q RISK OF A MIX NORTH SECTIONS OR EVEN A WET SNOW BY FRIDAY AS SYSTEM MOVES EAST. HIGHS MOSTLY IN THE 40S WITH LOWS IN THE 30S. REVIEW OF LOCAL FORECAST AREA TOOLS INDICATE 1 TO LOCALLY NEAR 2 INCHES OF RAIN OR MOSTLY RAIN OVER THIS PERIOD REMAINS ON TRACK. THIS SYSTEM IS SLOWING DOWN WHICH MAY ALLOW FOR EVEN MORE MOISTURE AND MAY RESULT IN EVEN SLIGHTLY HEAVIER AMOUNTS OF RAIN AND EVEN A WET SNOW AS OPEN GULF MOISTURE HAS MORE TIME TO POOL AHEAD OF THE FRONT. THIS SYSTEM BEARS CLOSE WATCHING DUE TO ITS STRENGTH...CURRENT TRACK TO THE FORECAST AREA. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 240 AM CDT SAT MAR 29 2014 STRATUS BASED AROUND 2000 TO 2500 FT AGL WILL CONTINUE TO LINGER OVER ALL OF EASTERN IOWA AND NORTHWEST ILLINOIS THROUGH THE MORNING HOURS. SOME CLEARING IS EXPECTED...BUT MAY TAKE UNTIL 18Z OR EVEN 20Z TO GO SCATTERED OVER LOCATIONS SOUTH OF DBQ ALONG THE MISSISSIPPI RIVER. MLI AND BRL ARE THUS KEPT IN MVFR CONDITIONS THIS MORNING. WINDS WILL OTHERWISE BE VERY LIGHT AND VARIABLE AS HIGH PRESSURE PASSES THROUGH THE AREA. VFR CONDITIONS ARE THEN LIKELY FROM LATE AFTERNOON THROUGH THE OVERNIGHT AT ALL SITES WITH LIGHT WINDS BECOMING SOUTHERLY TOWARD SUNRISE. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...NONE. IL...NONE. MO...NONE. && $$ SYNOPSIS...SHEETS SHORT TERM...SHEETS LONG TERM...NICHOLS AVIATION...SHEETS
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
205 AM EDT SAT MAR 29 2014 .UPDATE... ISSUED AT 150 AM EDT SAT MAR 29 2014 UPDATED THE GRIDS TO FINE TUNE THE POP CHANCES THROUGH DAWN. ALSO ADJUSTED THE T AND TD GRIDS PER THE LATEST OBS...TRENDS...AND NEAR TERM MODEL DATA. THESE TWEAKS HAVE BEEN SENT TO THE NDFD AND WEB SERVERS. UPDATE ISSUED AT 740 PM EDT FRI MAR 28 2014 LATEST HRRR AND RAP BOTH BACKING OFF ON PRECIPITATION CHANCES THROUGH THE OVERNIGHT HOURS. THE EXCEPTION IS IN A NARROW CORRIDOR ALONG THE STALLED OUT FRONTAL BOUNDARY DRAPED FROM JUST SOUTH OF HUNTINGTON...AND NEARLY ALONG THE I-64 CORRIDOR. THESE SHOWERS HAVE DEVELOPED AMIDST A CONVERGENCE ZONE...AND SOME INSTABILITY. THIS ACTIVITY SHOULD WANE AS WE HEAD INTO THE LATE EVENING HOURS...LEAVING THE AREA DRY THROUGH MUCH OF THE OVERNIGHT PERIOD. SOME RAIN MAY CREEP INTO THE I-75 CORRIDOR TOWARDS DAWN AHEAD OF THE MAIN LOBE OF ENERGY EXPECTED TO CROSS THE AREA SATURDAY MORNING. UNTIL THIS HAPPENS...IT LOOKS LIKE A DRIER FORECAST IS ON TAP TONIGHT. && .SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT) ISSUED AT 400 PM EDT FRI MAR 28 2014 A COLD FRONT HAS SLOWED ITS SOUTH AND EAST PROGRESS AS AN AREA OF LOW PRESSURE IS BEGINNING TO TAKE SHAPE OVER TX IN RESPONSE TO THE NEXT SHORTWAVE MOVING ACROSS THE PLAINS. THIS SHORTWAVE TROUGH WILL GRADUALLY WORK EAST TO MS RIVER VALLEY AND ENTER THE LOWER OH VALLEY TONIGHT AND THEN INTO THE EASTERN CONUS THROUGH THE END OF THE PERIOD. THE SOUTHERN END OF THE TROUGH IS FORECAST TO CLOSE OFF AND MOVE ACROSS THE AREA LATE SATURDAY AFTERNOON INTO SATURDAY NIGHT. THE SFC LOW IS EXPECTED TO TRACK TO THE CUMBERLAND PLATEAU IN TN BY DAWN ON SATURDAY. THE 12Z GFS IS GENERALLY THE STRONGEST WITH THE SFC LOW AT THAT POINT. THE SFC LOW SHOULD MOVE ACROSS THE SOUTHEAST PART OF THE AREA ON SATURDAY MORNING AND DEEPEN TO ABOUT 995 MB PER THE 12Z ECMWF AND 12Z GFS AS THE UPPER LOW DEVELOPS AND REACH THE DELMARVA BY THE END OF THE PERIOD. DESPITE THE MID LEVEL HEIGHT RISES CAPPING OFF CONVECTION THIS AFTERNOON FROM BRIEF SHORTWAVE RIDGING...THERE IS ENOUGH LOW LEVEL INSTABILITY FOR EXTENSIVE CU AND STRATOCU AND SOME SHOWERS. THESE FEW SHOWERS HAVE RECENTLY DEVELOP NEAR THE STALLING BOUNDARY AS MODEL GUIDANCE HAD SUGGESTED. SOME ISOLATED SHOWERS WILL REMAIN POSSIBLE THIS EVENING...BEFORE MOISTURE AND LIFT INCREASE AHEAD OF THE UPPER LEVEL TROUGH AND SFC WAVE TO TRACK NORTHEAST INTO THE TN VALLEY AND THEN INTO THE REGION BY EARLY ON SATURDAY. THE 12Z ECMWF AND GFS GUIDANCE SUGGEST VERY LITTLE IF ANY MEASURABLE PRECIPITATION TONIGHT WITH SOME DOWNSLOPE FLOW ACROSS MUCH OF THE AREA. HOWEVER... THE NAM AND 9Z AND 15Z SREF WERE IN THE LIKELY TO CAT RANGE IN MOST AREAS ACROSS THE REGION. PERSISTENCE AND ISC COLLABORATION LED TO CATEGORICAL POPS LATE IN ALL BUT THE BIG SANDY REGION. QPF TONIGHT WILL BE LIGHTER AND MUCH MORE SIGNIFICANT WELL WEST OF THE REGION AND WEST OF THE ANTICIPATED SFC LOW TRACK. AS THE SFC LOW TRACKS INTO WV THROUGH EARLY SAT AFTERNOON SOME COLDER AIR WILL BEGIN TO BE WRAPPED SOUTHEAST TOWARD THE REGION. A BAND OF SHOWERS OR RAIN WILL SHIFT EAST INTO EASTERN KY BY THE DAY ON SATURDAY. THIS SHOULD LEAD TO THE MOST WIDESPREAD PRECIP ACROSS THE REGION ON SATURDAY MORNING...WITH SOME DRY SLOTTING IN THE AFTERNOON TO EARLY EVENING...ESPECIALLY IN THE SOUTH AND SOUTHEAST. ELEVATED INSTABILITY DOES LINGER INTO SAT AM...SO AN ISOLATED RUMBLE OR TWO OF THUNDER CANNOT BE RULED OUT. TEMPERATURES WILL BE WARMEST IN THE AM AS THE SFC LOW MOVES ACROSS THE REGION AND THEN TEMPS WILL BEGIN TO DROP OFF DURING SAT AFTERNOON. TEMPS SHOULD REACH THE UPPER 30S TO LOW 40S ACROSS THE NORTH AND HIGHEST TERRAIN BY LATE AFTERNOON. AS THE SOUTHERN PORTION OF THE SHORTWAVE TROUGH CLOSES OFF INTO A CLOSED UPPER LEVEL LOW AND MOVES EAST INTO THE CENTRAL AND SOUTHERN APPALACHIANS... FURTHER COLD AIR ADVECTION AND INSTABILITY AS WELL AS UPSLOPE FLOW WILL LEAD TO ANOTHER ROUND OF SHOWERS MOVING ACROSS THE AREA FROM SAT EVENING INTO WELL INTO SAT NIGHT. THE NON NAM GUIDANCE SUGGESTS SOME DECENT QPF...WHILE THE THERMAL PROFILE GRADUALLY MOVES TOWARD ONE SUPPORTIVE OF SNOW SHOWERS...FIRST ACROSS THE FAR NW AND HIGHEST TERRAIN NEAR THE VA LINE AND THEN INTO THE LOWER ELEVATIONS...POSSIBLY BEFORE THE SHOWER CHANCES END. THE COLLING WOULD COME FROM A COMBINATION OF COLD ADVECTION...COOLING FROM LIFT AND SOME WETBULBING. WITH THE UPPER LOW TRACKING ACROSS THE AREA AT NIGHT...AND ANY SNOW GENERALLY FALLING AT NIGHT AS WELL SOME ACCUMULATION WILL BE POSSIBLE. MOST LOCATIONS WILL NOT GET MORE THAN A DUSTING... IF THAT FROM THIS. HOWEVER...LIGHT ACCUMULATIONS WILL BE POSSIBLE...PARTICULARLY RIDGES AT 2000 FEET AND ABOVE. AMOUNTS AT THESE HIGHEST ELEVATIONS COULD EXCEED 1 INCH WITH THE TOP OF BLACK MTN OR PINE MTN AND PERHAPS THE FLATWOODS AREA OF PIKE COUNTY GETTING AS MUCH AS 2 TO 3 INCHES. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 323 PM EDT FRI MAR 28 2014 THE EXTENDED FORECAST PERIOD BEGINS WITH THE MODELS IN VERY GOOD AGREEMENT. ON SUNDAY THE WILL BE AN UPPER LOW OVER SOUTH CENTRAL VIRGINIA. AT THE SURFACE...THE WRAP AROUND MOISTURE SHOULD SHOULD BE MOVING OUT OF THE AREA AND THE THE PRECIPITATION SHOULD BE ENDING. THE UPPER LOW WILL CONTINUE MOVING TO THE NORTHEAST AND THE NEXT SYSTEM WILL START MOVING TOWARD THE AREA. AS THE SYSTEM APPROACHES ON TUESDAY NIGHT...AN UPPER LOW WILL START DIGGING IN OVER THE WEST COAST. THIS WILL TEND THE KEEP THE FRONT FAIR STATIONARY NEAR EASTERN KENTUCKY. AT THIS TIME THE FRONT WILL BE FAIRLY WEAK AND IT WILL RESULT MOSTLY IN CLOUDS. THERE IS QUITE A BIT OF UNCERTAINTY AS TO EXACTLY WHERE THE FRONT WILL STALL OUT. AS THE UPPER TROUGH OUT WEST CONTINUES TOWARD THE AREA...THE FRONT WILL DEFINITELY BE TO THE NORTH OF THE AREA AND IT WILL KEEP EASTERN KENTUCKY IN THE WARM SECTOR. THE FRONT WILL BE MOVING VERY SLOWLY INTO AND THROUGH THE AREA AS WAVE DEVELOP ON THE FRONT OVER THE SOUTH CENTRAL PLAINS AND KEEP THE FRONT TO THE WEST OF THE AREA. THIS WILL KEEP WARM UNSTABLE AIR OVER EASTERN KENTUCKY AND WILL ALLOW SOME ISOLATED THUNDERSTORMS TO ACCOMPANY THE RAIN. THE FRONT IS EXPECTED TO MOVE ACROSS THE AREA ON THURSDAY NIGHT. BY THE END OF THE PERIOD...THERE MODELS ARE DIFFERING...SO THE TIMING OF THIS FRONT COULD CHANGE 6-18 HOURS BY THE TIME IT GETS HERE. THIS WILL KEEP THE HIGH TEMPERATURES NEAR 70 THROUGH THE EXTENDED PERIOD. ADJUSTED THE MODEL BLEND TOWARD THE NEW ECMWF. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 205 AM EDT SAT MAR 29 2014 DOWNSLOPING SOUTHEAST WINDS WILL LIKELY KEEP ANY LOWER CLOUDS AT BAY AND ALLOW VFR CONDITIONS TO CONTINUE THROUGH THE REMAINDER OF THE NIGHT. THE EXCEPTION COULD BE IN SOUTH CENTRAL KENTUCKY...WHERE LESS INFLUENCE ON DOWNSLOPING FLOW MAY MEAN A PERIOD OF MVFR CIGS TOWARD DAWN. THIS WOULD MAINLY IMPACT KSME AND PERHAPS KLOZ IN ADVANCE OF THE SHOWERS OF THE NEXT SYSTEM. RAIN LOOKS LIKE IT SHOULD NOT AFFECT TAF SITES UNTIL AFTER DAWN. AS THE RAIN COMES IN LATER IN THE MORNING...CEILINGS WILL LOWER TO MVFR BEFORE LIKELY REACHING IFR BY MIDDAY WHEN THE LOW LEVELS SATURATE. THE RAIN SHOWERS WILL CONTINUE THROUGH SATURDAY EVENING WITH SOME SNOW MIXING IN AFTER DARK AT MOST SITES. WINDS WILL BE RATHER LIGHT THROUGH THE BULK OF THE PERIOD. THE VARIABLE DIRECTION BECOME SOUTH AFTER SUNRISE AND THEN THE WINDS SWITCH TO THE WEST AROUND MIDDAY BEFORE BECOMING NORTHWEST AND PICKING UP TO NEAR 10 KTS FOR THE REMAINDER OF THE PERIOD AS A DEEPENING AREA OF LOW PRESSURE MOVES PAST. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...GREIF SHORT TERM...JP LONG TERM...JJ AVIATION...GREIF
AREA FORECAST DISCUSSION
NWS CARIBOU ME
513 PM EDT SAT MAR 29 2014 .SYNOPSIS... LOW PRESSURE WILL TRACK SLOWLY SOUTH OF THE AREA TONIGHT THROUGH EARLY NEXT WEEK. && .NEAR TERM /THROUGH SUNDAY/... AT THE START OF THE PERIOD THE MAJOR MODELS ARE SHOWING THE NEXT SYSTEM TO AFFECT OUR AREA CENTERED OVER THE CNTRL PORTIONS OF THE NC/VA BORDER...WITH A WARM FRONT EXTENDING NORTH TO THE SW COAST OF MAINE. THE MODEL INDICATE THAT THE LOW IS STILL DYNAMIC AT THIS POINT...BUT SHOWING THAT THE UPPER LEVEL LOW IS STARTING TO BECOME VERTICALLY STACKED WITH THE SURFACE LOW...THE BEGINNING PROCESS OF BECOME COLD CORE. BY MRNG THE LOW MOVES NE TO THE NJ COAST...PRECIP SPREADS ACROSS ERN MAINE INTO NRN MAINE. PCPN WILL BE SNOW...WITH SLEET AND FREEZING RAIN MIXED IN ACROSS THE INTERIOR DOWNEAST AND EAST CNTRL MAINE. AT THIS TIME ALL MODELS SHOWING A CLOSED LOW AT 500MB AND THE SFC LOW NEARLY VERTICALLY STACKED. BY THE END OF THE PERIOD...THE BULK OF THE PCPN MOVES EAST INTO NEW BRUNSWICK...THE LOW DRIFTS NORTH ALONG THE NJ COAST TO JUST SOUTH OF LONG ISLAND. THE UPPER LOW AND SFC LOW WILL BE VERTICALLY STACKED. THE GFS...GEM...AND ECMWF SHOW A NEW LOW IN THE ERN GULF OF MAINE THAT WILL BECOME THE NEW PRIMARY LOW FOR THIS SYSTEM AS IT TRACKS TOWARD NEW BRUNSWICK. LOADED THE HRRR MIN TEMP FOR THE OVRNGT...GEM MAX TEMP FOR TOMORROW. INTERPOLATED FROM MIN TO MAX FOR HRLY TEMPS. USED A BLEND OF NAM/GFS/GEM/ECMWF FOR HRLY DP/SKY/WND/POP. ADDED 15 PERCENT TO WINDS FOR GUSTS OVER LAND...25 PERCENT OVER WATERS. LOADED NAWAVE 4 FOR SEAS IN THE COASTAL WATERS. && .SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/... A VERTICALLY STACKED SURFACE/UPPER LOW WILL BEGIN TO MOVE SLOWLY NORTHEAST SUNDAY NIGHT. A NEARLY STATIONARY FRONTAL BOUNDARY WILL EXTEND NORTHEAST FROM THE SURFACE LOW. ISENTROPIC LIFT AND OVERRUNNING IN THE VICINITY OF THE FRONT WILL SUPPORT PRECIPITATION ACROSS THE FORECAST AREA SUNDAY NIGHT. HOWEVER...THE PROXIMITY OF THE FRONT TO THE COAST REMAINS UNCERTAIN. HAVE BASED THE FORECAST ON A SLOWER MOVEMENT OF THE SURFACE LOW AND THE FRONT REMAINING CLOSER TO THE COAST WHICH WILL KEEP MORE EXTENSIVE PRECIPITATION ACROSS THE FORECAST AREA. HIGH PRESSURE NORTH OF MAINE WILL CONTINUE TO PROVIDE LOW LEVEL COLD AIR ACROSS THE FORECAST AREA SUNDAY NIGHT INTO MONDAY. HOWEVER...WARMER AIR ALOFT WILL KEEP A WINTRY MIX ACROSS MUCH OF THE FORECAST AREA SUNDAY NIGHT. A WINTRY MIX WILL PERSIST ACROSS NORTHERN AND CENTRAL PORTIONS OF THE FORECAST AREA SUNDAY NIGHT...WITH RAIN TRANSITIONING TO A WINTRY MIX ACROSS DOWNEAST AREAS. WINTER STORM WARNINGS WILL REMAIN IN EFFECT ACROSS NORTHERN AREAS SUNDAY NIGHT...WITH WINTER WEATHER ADVISORIES ACROSS CENTRAL AREAS AND INTERIOR DOWNEAST PORTIONS OF THE FORECAST AREA. HAVE HELD WITH THE SLOWER MOVEMENT OF THE SYSTEM MONDAY...WHICH WILL KEEP LIGHT PRECIPITATION ACROSS THE FORECAST AREA. ACROSS NORTHERN AREAS EXPECT EXPECT A LIGHT WINTRY MIX...WITH A WINTRY MIX TRANSITIONING TO RAIN ACROSS CENTRAL AND DOWNEAST AREAS. THE SURFACE/UPPER LOW WILL MOVE EAST MONDAY NIGHT WHILE HIGH PRESSURE SLOWLY BUILDS SOUTH WITH DECREASING RAIN/SNOW SHOWER CHANCES ACROSS THE FORECAST AREA. A SLIGHT CHANCE OF SHOWERS COULD PERSIST DOWNEAST TUESDAY WITH THE EXITING LOW WHILE HIGH PRESSURE BUILDS ACROSS NORTHERN MAINE. TEMPERATURES WILL BE AT SLIGHTLY BELOW NORMAL LEVELS MONDAY/TUESDAY. && .LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... LOW PRESSURE WILL BE MOVING AWAY TUESDAY NIGHT AS A RIDGE OF HIGH PRESSURE BUILDS IN FROM THE WEST. THIS WILL BRING DRY AND RELATIVELY MILD WEATHER TUESDAY NIGHT INTO WEDNESDAY. A WEAK TROUGH MAY MOVE THROUGH ON THURSDAY BRINGING SOME CLOUDS AND PERHAPS LIGHT SHOWERS. OTHERWISE, THE DAY SHOULD REMAIN MOSTLY CLOUDY. HIGH PRESSURE SHOULD THEN BUILD IN BRINGING DRIER AND SEASONABLY MILD CONDITIONS ON FRIDAY. GOING INTO THE WEEKEND, LOTS OF UNCERTAINTY REGARDING WHETHER OR NOT A BLOCKING RIDGE OVER EASTERN CANADA CAN MAINTAIN THE DRY WEATHER. THE GFS KEEPS CONDITIONS DRY WHILE THE ECMWF BRINGS A TROUGH OF LOW PRESSURE THROUGH WITH A CHANCE FOR SOME RAIN OR SNOW SHOWERS. IN THE FORECAST WILL HAVE LOW CHANCE FOR RAIN OR SNOW SHOWERS NEXT WEEKEND. CURRENTLY DOES NOT LOOK LIKE ANY MAJOR STORMS ARE EXPECTED THROUGH NEXT WEEKEND, AND TEMPERATURES WILL BE NEAR NORMAL WHICH WILL BE CONSIDERABLY MILDER THAN THE VERY COLD CONDITIONS WE HAVE HAD IN MARCH. && .AVIATION /21Z SATURDAY THROUGH THURSDAY/... NEAR TERM: DETERIORATING CONDITIONS SOUTH TO NORTH AS THE LOW MOVES INTO THE AREA. MVFR CONDITIONS BHB...ALL OTHER SITES VFR TO START THE PERIOD THIS EVENING. BY 9PM IFR CONDITIONS BHB IN RAIN...BGR RAIN BCMG MXD. IFR CONDITIONS MOVE INTO HUL...PQI...CAR...FVE AFT 3AM...PCPN SNOW BCMG MXD AT HUL TOMORROW AFTN. IFR CONDITION WILL REMAIN ACROSS THE AREA THROUGH THE END OF THE PERIOD. PCPN TYPE SN FOR FVE...SN MAY MIX WITH PL BRIEFLY IN AFTN IN PQI AND CAR. SHORT TERM: IFR/LIFR CONDITIONS ARE EXPECTED ACROSS THE REGION SUNDAY NIGHT INTO EARLY MONDAY...WITH MVFR/IFR CONDITIONS LATER MONDAY. OCCASIONAL MVFR CONDITIONS COULD PERSIST ACROSS THE REGION MONDAY NIGHT. OCCASIONAL MVFR CONDITIONS COULD PERSIST ACROSS DOWNEAST AREAS EARLY TUESDAY. OTHERWISE...VFR CONDITIONS ARE EXPECTED ACROSS THE REGION TUESDAY. VFR CONDITIONS ARE EXPECTED ACROSS THE REGION WEDNESDAY. VFR CONDITIONS ARE EXPECTED ACROSS NORTHERN AREAS THURSDAY...WITH OCCASIONAL MVFR CONDITIONS POSSIBLE DOWNEAST. && .MARINE... NEAR TERM: THE LOW WILL TRANSIT SLOWLY SOUTH OF OF THE GULF OF MAINE. TODAYS TRACK IS FARTHER SOUTH THAN WAS PREVIOUS FORECASTED. WINDS STILL CALL FOR MARGINAL GALE FORCE WINDS FOR TOMORROW. WILL CONTINUE THE GALE WATCH. SHORT TERM: MARGINAL GALE CONDITIONS ARE POSSIBLE SUNDAY NIGHT INTO EARLY MONDAY NIGHT WHICH COULD REQUIRE GALE WARNINGS. VISIBILITIES WILL BE REDUCED IN RAIN SUNDAY NIGHT INTO EARLY MONDAY NIGHT...WITH LINGERING RAIN/SNOW SHOWERS POSSIBLE LATER MONDAY NIGHT INTO TUESDAY. && .HYDROLOGY... A FLOOD WATCH CONTINUES FOR DOWNEAST MAINE SUNDAY THROUGH MONDAY AFTERNOON. THE PRECIPITATION ASSOCIATED WITH THE UPCOMING STORM WILL LIKELY FALL MAINLY AS RAIN OR FREEZING RAIN IN THESE AREAS, ESPECIALLY ALONG THE COAST. TOTAL LIQUID PRECIPITATION AMOUNTS OF UP TO 3 INCHES ARE EXPECTED. IN ADDITION TO THIS RAIN...TEMPERATURES WILL REMAIN NEAR OR ABOVE FREEZING THROUGH SUNDAY ADDING SNOWMELT TO THE EQUATION. THE SNOWPACK IN THESE AREAS IS HIGHLY VARIABLE, RANGING FROM AROUND 6 INCHES ALONG THE COAST TO 2 FEET OR MORE IN THE INTERIOR. THERE IS 2 TO 4 INCHES OF WATER CONTAINED IN THE PACK ALONG THE COAST WITH 6 TO 8 INCHES FURTHER INLAND. WHILE THE DEEPER SNOW WILL BE ABLE TO ABSORB SOME OF THE RAIN...MUCH OF IT WILL BECOME RUNOFF IN ADDITION TO THE SNOWMELT. THIS MEANS DOWNEAST AREAS COULD POTENTIALLY SEE 4 INCHES OR MORE OF TOTAL RUNOFF. RIVERS WILL LIKELY RISE SUBSTANTIALLY AND POTENTIALLY CAUSE RIVER ICE TO BREAK UP...ESPECIALLY IN THOSE PLACES WHERE THE ICE COMPLETELY FLUSHED OUT IN JANUARY (MEANING THE ICE THERE NOW IS RELATIVELY WEAK). FOR THOSE RIVER STRETCHES THAT ARE ICE FREE...ICE COVER UPSTREAM MAY BREAK UP AND COLLECT DOWNSTREAM. IN ADDITION TO THE POTENTIAL FOR ICE JAMS, THIS AMOUNT OF RAINFALL AND RUNOFF WILL LIKELY LEAD TO PONDING OF WATER ON ROADWAYS AND MINOR FLOODING OF LOW-LYING POOR DRAINAGE AREAS. IN ADDITION, TIDAL LOCATIONS SUCH AS BANGOR WILL HAVE TO BE WATCHED CLOSELY AROUND THE TIME OF HIGH TIDE. THE CURRENT OFFICIAL NATIONAL WEATHER SERVICE FORECAST FOR THE PENOBSCOT RIVER AT BANGOR BRINGS THE GAUGE WITHIN 1 FOOT OF FLOOD STAGE WITH HIGH TIDE SUNDAY MORNING. PERSONS WITH INTERESTS ALONG WATERWAYS OR IN FLOOD-PRONE LOCATIONS ACROSS HANCOCK...WASHINGTON AND SOUTHERN PENOBSCOT COUNTIES SHOULD STAY TUNED FOR ADDITIONAL INFORMATION ON THIS SYSTEM. && .CAR WATCHES/WARNINGS/ADVISORIES... ME...WINTER STORM WARNING FROM 6 AM SUNDAY TO 8 AM EDT MONDAY FOR MEZ001-002. WINTER STORM WARNING FROM 2 AM SUNDAY TO 8 AM EDT MONDAY FOR MEZ003>006-010. WINTER WEATHER ADVISORY FROM 2 AM SUNDAY TO 8 AM EDT MONDAY FOR MEZ011-015>017-031-032. FLOOD WATCH FROM SUNDAY MORNING THROUGH MONDAY AFTERNOON FOR MEZ015>017-029-030. MARINE...GALE WATCH FROM SUNDAY AFTERNOON THROUGH LATE MONDAY NIGHT FOR ANZ050>052. && $$ NEAR TERM...NORTON SHORT TERM...NORCROSS LONG TERM...BLOOMER AVIATION...NORTON/NORCROSS MARINE...NORTON/NORCROSS HYDROLOGY...NORTON
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
1021 PM EDT SUN MAR 30 2014 .SYNOPSIS... LOW PRESSURE WILL MOVE AWAY FROM THE REGION TONIGHT THROUGH MONDAY. HIGH PRESSURE WILL BUILD OVERHEAD MONDAY NIGHT INTO TUESDAY. A COLD FRONT WILL MOVE INTO THE AREA TUESDAY NIGHT AND WEDNESDAY. THIS BOUNDARY WILL STALL OUT NEARBY THROUGH THE END OF THE WEEK. && .NEAR TERM /THROUGH MONDAY/... LOPRES ANALYZED AT 1000 MB MVG OFF LONG ISLAND. IR SATPIX AND WATER VAPOR LOOP CONT TO DEPICT A WELL WRAPPED SYSTEM...THE BACK EDGE OF WHICH APPROX FM FDK-IAD-EZF. ITS NUDGED LTL SINCE 00Z. W/IN THE HVYR PCPN RATES ENUF COLD AIR BEING DRAGGED DOWN TO SUPPORT SNW...OTRW PCPN FALLING AS RA. NRN CARROLL CNTY IN THE BULLSEYE... W/ A PERSISTENT BAND OF SNW RESULTING IN 1-2 INCH/HR SNWFL RATES FOR SVRL HRS. HV NRMS REPORTS ARND 8 INCHES...AND XPCT A CPL MORE HRS OF SNW. THEREFORE...HV UPGRADED CARROLL CNTY TO A WINTER STORM WARNING. ELSW...GNLY AN INCH OR TWO...IF THAT. AS PCPN EXITS...A MORE FVRBL ENVIRONMENT FOR VERT MOMENTUM TRANSPORT MOVES IN. THIS WAS REALIZED 23Z-00Z AT MRB/HRG/LUA. IN THE PEAKS OF THE APLCNS...ITS BEEN WINDY ALL DAY...BUT THE 40-50 KT AT H9-8 NOT MIXING. LWX 00Z RAOB DOES DEPICT A SFC-BASED INVSN...AS WELL AS A LARGER ONE ARND 800MB. WE DO HV 40-50 KT AVBL TO MIX. LTST RAP DOING BEST JOB AT CAPTURING IT. ITS ALSO THE ONLY GDNC THAT SUGGESTS WINDS MAY BE AN ISSUE TNGT. WHILE BELIEVE THE WINDOW ONLY OPEN TIL ABT 04-06Z /TIL DIURNAL EFFECTS AND REDUCED P-GRAD HAMPER EFFORT/...DO FEEL THERE IS A THREAT TIL THEN. HV EXPANDED WND ADVY TO INCL AREAS SHOWING PROMISE...INCL MRB/HGR/IAD/HEF. SKIES CLRG OUT ACRS THE PTMC HIGHLANDS...EXPANDING INTO THE SHEN VLY. THAT WL ONLY AIDE IN VERT MIXING. SINCE TEMPS HV BEEN GOING DOWN AND THEN UP SO FAR THIS PM...ITS BEEN A BIT OF A MOVING TARGET FOR GDNC. TWEAKED TEMPS USING LAMP...WHICH RESULTED IN A DOWNWARD ADJUSTMENT ALMOST AREAWIDE. HIGH PRESSURE WILL MOVE INTO THE OHIO VALLEY MONDAY AND NWRLY FLOW AND CLEAR CONDTIONS WILL ALLOW DOWNSLOPING FLOW TO BRING TEMPS TO THE 60S MONDAY. GUSTY WINDS ARE EXPECTED AS THE TIGHT PRESSURE GRADIENT BETWEEN THE APPROACHING HIGH AND EXITING LOW CONTINUE ACROSS THE REGION. && .SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/... HIGH PRESSURE WILL MOVE INTO THE REGION MONDAY NIGHT AND TUESDAY AS AN UPPER LEVEL RIDGE MOVES OVERHEAD. LIGHT SRLY WINDS WILL DRAW WARMER TEMPERATURES WITH MAX TEMPS REACHING THE LOW 60S IN NE MD AND RIDGES TO THE MID 70S IN THE PIEDMONT AND CENTRAL VA INCLUDING VALLEY LOCATIONS. A WEAK COLD FRONT WILL APPROACH FROM THE WEST TUESDAY NIGHT AND RAIN WILL DISSIPATE BEFORE IT REACHES THE POTOMAC HIGHLANDS. AS THE FRONT MOVES INTO THE REGION...ONLY SCT CLOUDS ARE EXPECTED TO CROSS OVER THE MTNS AND WEST OF THE BLUE RIDGE BEFORE DISSIPATING BY THE TIME IT REACHES THE I-95 CORRIDOR. THE COLD FRONT WILL STALL ACROSS THE REGION WEDNESDAY AND MULTIPLE DISTURBANCES WILL CROSS ALONG THE BOUNDARY. CLOUDS WILL INCREASE DURING THE DAY WEDNESDAY AND AS THE BOUNDARY LAYER SATURATES RAIN WILL EVENTUALLY REACH THE POTOMAC HIGHLANDS AND NRN MD BY WEDNESDAY EVENING. TEMPS WILL REACH THE LOW 60S IN NRN MD AND THE RIDGELINES TO THE MID 70S IN CENTRAL VA. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... HIGH PRESSURE WILL BUILD OVERHEAD MONDAY BEFORE MOVING OFF THE COAST DURING THE MIDDLE PORTION OF NEXT WEEK. A SOUTHERLY FLOW WILL USHER IN MILDER CONDITIONS DURING THE MIDDLE PORTION OF NEXT WEEK. SURFACE LOW STORM TAKING NORTHERN TRACK ACROSS GREAT LAKES AND EASTERN CANADA TUESDAY THROUGH WEDNESDAY WILL NOT AFFECT THE AREA. THE NEXT STORM SYSTEM MAY IMPACT THE AREA WEDNESDAY NIGHT INTO THURSDAY. && .AVIATION /02Z MONDAY THROUGH FRIDAY/... MVFR FLGT CONDS ACRS BALT-WASH AREA TERMINALS ATTM...DUE MAINLY TO CIGS...W/ VFR CONDS AT CHO/MRB. XPCT CONDS TNGT IMPVG TO VFR. HWVR...NW WNDS WL BE PICKING UP THIS EVNG AS WELL...W/ G30-35 KT XPCTD ACRS ALL TERMINALS...AND G40-45 KT PSBL FOR CHO/IAD/MRB. WNDS ALREADY AT 40-50 KT A CPL THSND FT UP...AND HV THAT REFLECTED VIA LLWS RMK. VFR CONDS WL PREVAIL MONDAY. WL STILL HV GUSTY NW WNDS FOR THE MRNG PUSH...W/ G30KT PSBL. WINDS WILL DIMINISH MIDDAY-AFTN AS HIGH PRESSURE MOVES INTO THE REGION. OUTLOOK... TUE-WED...VFR. THU-FRI...MVFR TO OCNL IFR AS CDFNT DROPS ACRS THE TERMINALS AND STALLS. && .MARINE... NW WNDS PRESENTLY IN LOW-END SCA RANGE. HWVR...GDNC DEPICTING A STRONG GLW PSBL. PCPN ACRS WATERS PREVENTING MUCH MIXING...BUT IT/LL BE PULLING OUT TNGT AS LOPRES EXITS TO THE NE. THEREFORE... WL KEEP GLW GOING THRU TNGT ALL WATERS AND THRU MON FOR THE MD BAY AND LWR PTMC. MIXING SHUD IMPRV OVNGT. WINDS WILL DIMINISH MONDAY AFTERNOON AND EVENING AS HIGH PRESSURE MOVES INTO THE REGION. SLY WINDS WILL INCREASE TUESDAY. SCA NOT XPCTD THRU END OF PD. && .LWX WATCHES/WARNINGS/ADVISORIES... DC...NONE. MD...WIND ADVISORY UNTIL 6 AM EDT MONDAY FOR MDZ003-501-502. WINTER WEATHER ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR MDZ006- 009-010. WINTER STORM WARNING UNTIL 1 AM EDT MONDAY FOR MDZ005. VA...WIND ADVISORY UNTIL 6 AM EDT MONDAY FOR VAZ025>031-036>040-042- 051-052-501>504. WV...WIND ADVISORY UNTIL 6 AM EDT MONDAY FOR WVZ050>053-055-501>506. MARINE...GALE WARNING UNTIL 6 PM EDT MONDAY FOR ANZ530>534-537>543. SMALL CRAFT ADVISORY FROM 6 AM TO 6 PM EDT MONDAY FOR ANZ535- 536. GALE WARNING UNTIL 6 AM EDT MONDAY FOR ANZ535-536. && $$ SYNOPSIS...HTS/HAS NEAR TERM...HTS/JRK SHORT TERM...HAS LONG TERM...CEM AVIATION...HTS MARINE...HTS/JRK/HAS
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
902 PM EDT SUN MAR 30 2014 .SYNOPSIS... LOW PRESSURE WILL MOVE AWAY FROM THE REGION TONIGHT THROUGH MONDAY. HIGH PRESSURE WILL BUILD OVERHEAD MONDAY NIGHT INTO TUESDAY. A COLD FRONT WILL MOVE INTO THE AREA TUESDAY NIGHT AND WEDNESDAY. THIS BOUNDARY WILL STALL OUT NEARBY THROUGH THE END OF THE WEEK. && .NEAR TERM /THROUGH MONDAY/... LOPRES ANALYZED AT 1000 MB OFF JFK. IR SATPIX AND WATER VAPOR LOOP CONT TO DEPICT A WELL WRAPPED SYSTEM...THE BACK EDGE OF WHICH APPROX FM FDK-IAD-EZF. W/IN THE HVYR PCPN RATES ENUF COLD AIR BEING DRAGGED DOWN TO SUPPORT SNW...OTRW PCPN FALLING AS RA. NRN CARROLL CNTY IN THE BULLSEYE...NEARING WRNG LVL SNW. ELSW...GNLY AN INCH OR TWO...IF THAT. IN MANY CASES TAFTN-EVNG TEMPS DROPPED WHEN SNW BEGAN...BUT ONCE PCPN LIGHTENED TEMPS ROSE AND SNW MELTED. XPCT THAT SAME EVOLUTION TNGT FOR N-CENTRL/NERN MD...ALTHO THERE MAY BE A BIT TOO MUCH SNOW ACRS NRN CARROLL CNTY FOR IT TO ALL MELT AT ONCE. E OF CURRENT ADVY AREA...DO NOT XPCT MORE THAN AN INCH...AND HV NO PLANS TO EXPAND WINTER ADVY BYD CURRENT CONFIGURATION. AS PCPN EXITS...A MORE FVRBL ENVIRONMENT FOR VERT MOMENTUM TRANSPORT MOVES IN. THIS HAS BEEN REALIZED PAST HR AT MRB/HRG/LUA. IN THE PEAKS OF THE APLCNS...ITS BEEN WINDY ALL DAY...BUT THE 40-50 KT AT H9-8 NOT MIXING. LWX 00Z RAOB DOES DEPICT A SFC-BASED INVSN...AS WELL AS A LARGER ONE ARND 800MB. WE DO HV 40-50 KT AVBL TO MIX. LTST RAP DOING BEST JOB AT CAPTURING IT. ITS ALSO THE ONLY GDNC THAT SUGGESTS WINDS MAY BE AN ISSUE TNGT. WHILE BELIEVE THE WINDOW ONLY OPEN TIL ABT 04-06Z /TIL DIURNAL EFFECTS AND REDUCED P-GRAD HAMPER EFFORT/...DO FEEL THERE IS A THREAT TIL THEN. HV EXPANDED WND ADVY TO INCL AREAS SHOWING PROMISE...INCL MRB/HGR/IAD/HEF. SKIES CLRG OUT ACRS THE PTMC HIGHLANDS ATTM. THAT WL ONLY AIDE IF VERT MIXING. SINCE TEMPS HV BEEN GOING DOWN AND THEN UP SO FAR THIS PM...ITS BEEN A BIT OF A MOVING TARGET FOR GDNC. HVNT MADE MANY CHGS THUS FAR. WL TWEAK ALTER ONCE LAMP HAS A CHANCE TO CATCH UP. HIGH PRESSURE WILL MOVE INTO THE OHIO VALLEY MONDAY AND NWRLY FLOW AND CLEAR CONDTIONS WILL ALLOW DOWNSLOPING FLOW TO BRING TEMPS TO THE 60S MONDAY. GUSTY WINDS ARE EXPECTED AS THE TIGHT PRESSURE GRADIENT BETWEEN THE APPROACHING HIGH AND EXITING LOW CONTINUE ACROSS THE REGION. && .SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/... HIGH PRESSURE WILL MOVE INTO THE REGION MONDAY NIGHT AND TUESDAY AS AN UPPER LEVEL RIDGE MOVES OVERHEAD. LIGHT SRLY WINDS WILL DRAW WARMER TEMPERATURES WITH MAX TEMPS REACHING THE LOW 60S IN NE MD AND RIDGES TO THE MID 70S IN THE PIEDMONT AND CENTRAL VA INCLUDING VALLEY LOCATIONS. A WEAK COLD FRONT WILL APPROACH FROM THE WEST TUESDAY NIGHT AND RAIN WILL DISSIPATE BEFORE IT REACHES THE POTOMAC HIGHLANDS. AS THE FRONT MOVES INTO THE REGION...ONLY SCT CLOUDS ARE EXPECTED TO CROSS OVER THE MTNS AND WEST OF THE BLUE RIDGE BEFORE DISSIPATING BY THE TIME IT REACHES THE I-95 CORRIDOR. THE COLD FRONT WILL STALL ACROSS THE REGION WEDNESDAY AND MULTIPLE DISTURBANCES WILL CROSS ALONG THE BOUNDARY. CLOUDS WILL INCREASE DURING THE DAY WEDNESDAY AND AS THE BOUNDARY LAYER SATURATES RAIN WILL EVENTUALLY REACH THE POTOMAC HIGHLANDS AND NRN MD BY WEDNESDAY EVENING. TEMPS WILL REACH THE LOW 60S IN NRN MD AND THE RIDGELINES TO THE MID 70S IN CENTRAL VA. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... HIGH PRESSURE WILL BUILD OVERHEAD MONDAY BEFORE MOVING OFF THE COAST DURING THE MIDDLE PORTION OF NEXT WEEK. A SOUTHERLY FLOW WILL USHER IN MILDER CONDITIONS DURING THE MIDDLE PORTION OF NEXT WEEK. SURFACE LOW STORM TAKING NORTHERN TRACK ACROSS GREAT LAKES AND EASTERN CANADA TUESDAY THROUGH WEDNESDAY WILL NOT AFFECT THE AREA. THE NEXT STORM SYSTEM MAY IMPACT THE AREA WEDNESDAY NIGHT INTO THURSDAY. && .AVIATION /01Z MONDAY THROUGH FRIDAY/... MVFR FLGT CONDS ACRS BALT-WASH AREA TERMINALS ATTM...DUE MAINLY TO CIGS...W/ VFR CONDS AT CHO/MRB. XPCT CONDS TNGT IMPVG TO VFR. HWVR...NW WNDS WL BE PICKING UP THIS EVNG AS WELL...W/ G30-35 KT XPCTD ACRS ALL TERMINALS...AND G40-45 KT PSBL FOR CHO/IAD/MRB. WNDS ALREADY AT 40-50 KT A CPL THSND FT UP...AND HV THAT REFLECTED VIA LLWS RMK. VFR CONDS WL PREVAIL MONDAY. WL STILL HV GUSTY NW WNDS FOR THE MRNG PUSH...W/ G30KT PSBL. WINDS WILL DIMINISH MIDDAY-AFTN AS HIGH PRESSURE MOVES INTO THE REGION. OUTLOOK... TUE-WED...VFR. THU-FRI...MVFR TO OCNL IFR AS CDFNT DROPS ACRS THE TERMINALS AND STALLS. && .MARINE... NW WNDS PRESENTLY IN LOW-END SCA RANGE. HWVR...GDNC DEPICTING A STRONG GLW PSBL. PCPN ACRS WATERS PREVENTING MUCH MIXING...BUT IT/LL BE PULLING OUT TNGT AS LOPRES EXITS TO THE NE. THEREFORE... WL KEEP GLW GOING THRU TNGT ALL WATERS AND THRU MON FOR THE MD BAY AND LWR PTMC. MIXING SHUD IMPRV OVNGT. WINDS WILL DIMINISH MONDAY AFTERNOON AND EVENING AS HIGH PRESSURE MOVES INTO THE REGION. SLY WINDS WILL INCREASE TUESDAY. SCA NOT XPCTD THRU END OF PD. && .LWX WATCHES/WARNINGS/ADVISORIES... DC...NONE. MD...WIND ADVISORY UNTIL 6 AM EDT MONDAY FOR MDZ003-501-502. WINTER WEATHER ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR MDZ005- 006-009-010. VA...WIND ADVISORY UNTIL 6 AM EDT MONDAY FOR VAZ025>031-036>040-042- 051-052-501>504. WV...WIND ADVISORY UNTIL 6 AM EDT MONDAY FOR WVZ050>053-055-501>506. MARINE...GALE WARNING UNTIL 6 PM EDT MONDAY FOR ANZ530>534-537>543. SMALL CRAFT ADVISORY FROM 6 AM TO 6 PM EDT MONDAY FOR ANZ535- 536. GALE WARNING UNTIL 6 AM EDT MONDAY FOR ANZ535-536. && $$ SYNOPSIS...HTS/HAS NEAR TERM...HTS/JRK SHORT TERM...HAS LONG TERM...CEM AVIATION...HTS MARINE...HTS/JRK/HAS
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
554 PM CDT Sat Mar 29 2014 .SHORT TERM: (Through Late Tonight) Issued at 320 PM CDT Sat Mar 29 2014 Pesky stratus seems to be both clearing and eroding at a snails pace this afternoon and has a done number on the temperatures. Present indications based on satellite trends and the RAP which has handled the low clouds best, is that areas generally along and east of the MS River will see clouds into early evening with clearing from mid-late evening. Otherwise the expansive NE-SW high pressure system currently extending from WI into TX will slide east across the region tonight with the axis centered thru SE MO and southern IL at 12z. The slow clearing trend of the clouds along with light winds overnight across the SE third of the CWA has prompted me to add a mention of fog overnight. Glass .LONG TERM: (Sunday through Next Saturday) Issued at 320 PM CDT Sat Mar 29 2014 It finally looks like the warm-up will commence on Sunday. Heights aloft that begin rising tonight in the wake of the departing upper trof, will continue to rise on Sunday while the surface high retreats and low level southerly flow and warm advection get underway. There should be no low clouds to deal with a just some thin high clouds filtering across the region. The current forecast leveraging the warmer temperatures looks right on the mark and no changes were made. The warmer temps combined with low afternoon RH values and increasing southerly winds support an elevated fire danger threat across central and east central MO, which will be highlighted in the HWO. Continued southerly low level flow on Sunday night will lead to "milder" min temperatures and a slow return in low level moisture. The aforementioned expansive surface high and its southern extent will initially have a profounded effect on trajectories and delay quality moisture return. However mid level moisture won`t be an issue and this along with the eastern edge of steeper mid level lapse rates spreads into central MO just before daybreak on Monday. These ingredients along with the leading edge of forcing aloft associated with an upstream trof, suggests potential for some high-based scattered showers/thunderstorms and hence have added some slight chance pops. The week ahead looks especially active. The migratory upper trof partly responsible for the slight chance pops late Sunday night will move across the region Monday afternoon and early evening spreading height falls and cooling aloft along with a plume of steep mid level lapse rates. This combined with a gradual increase in low level moisture and forcing should be sufficient for scattered elevated showers/thunderstorms within the warm sector, moving through central and northeast MO during the morning gradually dwindling in coverage during the afternoon as they move east. By the time the cold front moves through the area Monday night, forcing aloft appears to have outrun the front and boundary layer moisture and hence instability are quite weak. I suspect anything that might be able to develop with be quite spotty and just have a slight chance pop. The most active period will be late Tuesday night into Thursday. The front that moves through Monday night will move back north and waver across the region. The warm sector air mass south of this boundary will become quite unstable thanks to continued northward return of quality Gulf moisture and the presence of steep mid level lapse rates, and with a strong low level jet evolving there will be good elevated instability and forcing north this boundary. The models differ quite a bit on the position of the next formidable migratory upper trof and the position of attendant surface low(s) and this boundary. While all the guidance supports a stormy period, the more northern position which has been consistently advertised by the ECMWF would lead to a much more volatile set-up. Glass && .AVIATION: (For the 00z TAFs through 00z Sunday Evening) Issued at 546 PM CDT Sat Mar 29 2014 Specifics for KCOU: Although light fog is possible tonight across the region, KCOU experienced sufficient daytime mixing to limit the overnight fog potential. Winds start to increase by 12z due to the tightening pressure gradient between a surface high to the southeast and a developing low to the northwest. Specifics for KSTL, KSUS, KCPS, KUIN: Stratus was slow to clear today and nearly clear skies with light winds are expected overnight. The combination of limited daytime mixing and good radiational cooling conditions will probably lead to light fog formation, especially near and east of the Mississippi River. Winds start to increase by 12z due to the tightening pressure gradient between a surface high to the southeast and a developing low to the northwest. Kanofsky && .LSX WATCHES/WARNINGS/ADVISORIES: MO...NONE. IL...NONE. && $$ WFO LSX
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
324 PM CDT Sat Mar 29 2014 .SHORT TERM: (Through Late Tonight) Issued at 320 PM CDT Sat Mar 29 2014 Pesky stratus seems to be both clearing and eroding at a snails pace this afternoon and has a done number on the temperatures. Present indications based on satellite trends and the RAP which has handled the low clouds best, is that areas generally along and east of the MS River will see clouds into early evening with clearing from mid-late evening. Otherwise the expansive NE-SW high pressure system currently extending from WI into TX will slide east across the region tonight with the axis centered thru SE MO and southern IL at 12z. The slow clearing trend of the clouds along with light winds overnight across the SE third of the CWA has prompted me to add a mention of fog overnight. Glass .LONG TERM: (Sunday through Next Saturday) Issued at 320 PM CDT Sat Mar 29 2014 It finally looks like the warm-up will commence on Sunday. Heights aloft that begin rising tonight in the wake of the departing upper trof, will continue to rise on Sunday while the surface high retreats and low level southerly flow and warm advection get underway. There should be no low clouds to deal with a just some thin high clouds filtering across the region. The current forecast leveraging the warmer temperatures looks right on the mark and no changes were made. The warmer temps combined with low afternoon RH values and increasing southerly winds support an elevated fire danger threat across central and east central MO, which will be highlighted in the HWO. Continued southerly low level flow on Sunday night will lead to "milder" min temperatures and a slow return in low level moisture. The aforementioned expansive surface high and its southern extent will initially have a profounded effect on trajectories and delay quality moisture return. However mid level moisture won`t be an issue and this along with the eastern edge of steeper mid level lapse rates spreads into central MO just before daybreak on Monday. These ingredients along with the leading edge of forcing aloft associated with an upstream trof, suggests potential for some high-based scattered showers/thunderstorms and hence have added some slight chance pops. The week ahead looks especially active. The migratory upper trof partly responsible for the slight chance pops late Sunday night will move across the region Monday afternoon and early evening spreading height falls and cooling aloft along with a plume of steep mid level lapse rates. This combined with a gradual increase in low level moisture and forcing should be sufficient for scattered elevated showers/thunderstorms within the warm sector, moving through central and northeast MO during the morning gradually dwindling in coverage during the afternoon as they move east. By the time the cold front moves through the area Monday night, forcing aloft appears to have outrun the front and boundary layer moisture and hence instability are quite weak. I suspect anything that might be able to develop with be quite spotty and just have a slight chance pop. The most active period will be late Tuesday night into Thursday. The front that moves through Monday night will move back north and waver across the region. The warm sector air mass south of this boundary will become quite unstable thanks to continued northward return of quality Gulf moisture and the presence of steep mid level lapse rates, and with a strong low level jet evolving there will be good elevated instability and forcing north this boundary. The models differ quite a bit on the position of the next formidable migratory upper trof and the position of attendant surface low(s) and this boundary. While all the guidance supports a stormy period, the more northern position which has been consistently advertised by the ECMWF would lead to a much more volatile set-up. Glass && .AVIATION: (For the 18z TAFs through 18z Sunday Afternoon) Issued at 201 PM CDT Sat Mar 29 2014 MVFR cigs slow to clear out of taf sites, so backed off on scattering clouds out especially for KUIN and STL metro area tafs. Otherwise, winds to remain from the north this afternoon, then become light and variable tonight as clouds scatter out. Some concern about light fog tonight, but confidence is low at this time. By Sunday morning, surface ridge to move off to the east allowing winds to pickup from the south around 10kts. Specifics for KSTL: MVFR cigs slow to clear out of taf sites, so backed off on scattering clouds out til after 21z. Otherwise, winds to remain from the north this afternoon, then become light and variable by 09z. Some concern about light fog tonight, but confidence is low at this time so left mention out for now. By 14z Sunday morning, surface ridge to move off to the east allowing winds to pickup from the south around 10kts. Byrd && .LSX WATCHES/WARNINGS/ADVISORIES: MO...NONE. IL...NONE. && $$ WFO LSX
AREA FORECAST DISCUSSION...UPDATED
NWS BILLINGS MT
916 PM MDT SUN MAR 30 2014 .UPDATE... ANALYSIS THIS EVENING INDICATES STRONG 700MB FRONTOGENESIS EXTENDING FORM THE BIG HORNS NORTHEASTWARD INTO CUSTER COUNTY. THIS CORRELATES WITH THE BEST SYNOPTIC PRECIPITATION POTENTIAL AND RADAR IMAGES. COLD AIR FROM THE NORTH IS SLOWLY SPREADING FROM MUSSELSHELL COUNTY SOUTH AND A LITTLE EAST. HRRR MODEL DEPICTION OF CHANGE OVER TO ALL SNOW HAS DONE WELL ACCORDING TO SEVERAL REPORTS FROM OUR SPOTTERS. CHANGE TO ALL SNOW LINE APPEARS TO CURRENTLY BE JUST EAST OF A SHERIDAN TO MILES CITY LINE...AND GRADUALLY SHIFTING EAST/SOUTHEAST. THE SOUTHEAST CORNER WILL LIKELY SHIFT OVER AROUND MIDNIGHT. EXCELLENT MOISTURE...STRONG Q VECTOR FORCING/FRONTOGENESIS AND A SURFACE LOW WINDING UP IN WEST CENTRAL NEBRASKA WILL LIKELY LEAD TO BLIZZARD OR NEAR BLIZZARD CONDITIONS IN OUR FAR EASTERN ZONES. THIS HANDLED WELL BY CURRENT HIGHLIGHTS. SHERIDAN COUNTY ALSO LIKELY TO BE POUNDED WITH HEAVY SNOW AND BLOWING SNOW AFFECTING I-90. UPSLOPE AREAS OF BEARTOOTHS AND BIG HORNS WILL ALSO BE HEAVILY AFFECTED OVERNIGHT. ONLY CHANGE WAS TO NUDGE THE HEAVIEST SNOWFALL ACCUMULATIONS NORTHWARD A BIT. LOWERED BILLINGS SNOWFALL A LITTLE BASED ON FACT WE HAVE NOT REALLY ACCUMULATED MUCH YET. SEEMS WE WILL BE ON EDGE OF THE CORRIDOR OF HEAVY SNOWFALL OVERNIGHT AS USUAL. BT && .SHORT TERM...VALID FOR MON AND TUE... MAJOR SPRING STORM TO IMPACT THE AREA TONIGHT WITH RAIN CHANGING TO ALL SNOW BY LATE AFTERNOON. WATER VAPOR SATELLITE SHOWING THE UPPER TROUGH MOVING OVER THE ROCKIES WHICH IS ALREADY IMPACTING OUR FORECAST AREA WITH STRONG DIFFLUENT FLOW ALOFT. HEAVY SNOW HAS BEEN FALLING OVER OUR SOUTHWEST MOUNTAINS TODAY AND IS CURRENTLY MOVING INTO THE FOOTHILLS AND THE PARADISE VALLEY TO LIVINGSTON. SATELLITE ALSO SHOWING AMPLE PACIFIC MOISTURE CONTINUING TO MOVE NORTHWARD INTO OUR AREA. POOL OF LOW LEVEL MOISTURE OVER THE EASTERN DATKOA`S WILL BEGIN ADVECTING INTO OUR AREA THIS EVENING AS MID LEVEL EASTERLY WINDS DEVELOP. PW`S OVER OUR AREA ARE ABOUT 140 PERCENT ABOVE NORMAL. VERY DYNAMIC UPPER TROUGH WILL BRING STRONG FRONTOGENETIC FORCING/ISENTROPIC LIFT AND DEEP OMEGA FIELD ACROSS THE FORECAST AREA TONIGHT. BUFKIT ALSO SHOWING DEEP DENDRITIC LAYER FROM SURFACE TO 650 MB OVER THE AREA TONIGHT. COLD FRONT WILL SAG SOUTHWARD INTO OUR AREA LATE THIS AFTERNOON AND SHOULD PUSH THROUGH THE ENTIRE AREA BY 00Z. SURFACE LOW PRESSURE MOVING ACROSS EASTERN WYOMING TONIGHT WHICH WILL WRAP STRONG WINDS INTO BAKER SOUTH TO ALZADA. WITH A FOOT OF SNOW EXPECTED THERE OVERNIGHT AND WINDS GUSTS TO 50 MPH...WILL KEEP BLIZZARD WARNING GOING THERE. THE STRONG WINDS WILL PRODUCE WHITEOUT CONDITIONS ALONG WITH 2 TO 4 FOOT SNOW DRIFTS. HEAVY WET SNOW COMBINED WITH THE STRONG WINDS COULD CAUSE POWER OUTAGES. 6 TO 12 INCHES OF SNOW EXPECTED FROM MCLEOD EAST THROUGH RED LODGE...THEN EAST THROUGH HARDIN TO BROADUS. SHERIDAN WILL ALSO PICKUP NEARLY A FOOT OF SNOW. 3 TO 5 INCHES EXPECTED FROM LIVINGSTO BILLINGS BY MORNING. NO CHANGES WILL BE MADE TO CURRENT WARNINGS OR ADVISORIES AS THIS VERY POWERFUL STORM SYSTEM MOVES ACROSS THE AREA TONIGHT. THE SYSTEM WILL BEGIN EXITING THE AREA MONDAY AFTERNOON WITH PRECIPITATION TAPERING OFF FROM WEST TO EAST. UNSTABLE NORTHWEST FLOW WILL SET UP OVER THE AREA TUESDAY FOR A CHANCE OF SCATTERED RAIN OR SNOW SHOWERS. TEMPERATURES WILL CONTINUE TO RUN ABOUT 10 TO 15 DEGREES BELOW NORMAL MONDAY AND TUESDAY. RICHMOND .LONG TERM...VALID FOR WED...THU...FRI...SAT...SUN... EXTENDED MODELS ARE IN BETTER AGREEMENT TODAY AS THE OVERALL PATTERN WILL CONSIST OF A COUPLE OF UPPER LEVEL LOWS MOVING ACROSS THE CENTRAL AND NORTHERN ROCKIES. THE FIRST LOW MOVES ONTO THE CALIFORNIA COAST WEDNESDAY AND THE SECOND TOWARD THE END OF THE WEEK. THE FIRST SYSTEM IS THE STRONGEST WITH A WELL DEFINED LOW BUT AS IT MOVES INLAND THE MAIN PIECE OF ENERGY BREAKS APART AS THE UPPER FLOW BECOMES SPLIT. THIS SPLIT FLOW CONTINUES INTO SATURDAY RESULTING IN PIECES OF ENERGY GOING TO THE NORTH AND SOUTH OF OUR FORECAST AREA WITH THE STRONGEST ENERGY STAYING TO OUR SOUTH. HOWEVER...THERE WILL BE ENOUGH ENERGY OVER THE FORECAST AREA TO WARRANT SCATTERED RAIN AND SNOW SHOWERS WEDNESDAY AND THURSDAY WITH THE SNOW SHOWER ACTIVITY MAINLY CONFINED TO THE WESTERN MOUNTAINS AND ADJACENT FOOTHILLS FOR FRIDAY. TEMPERATURES WILL BE BELOW NORMAL WEDNESDAY AND THURSDAY BEFORE REBOUNDING TO AROUND NORMAL FRIDAY AND POSSIBLY SLIGHTLY ABOVE NORMAL FOR NEXT WEEKEND. HOOLEY && .AVIATION... CONDITIONS FROM RED LODGE TO KBIL TO ROUNDUP E WILL BE IFR TO LIFR IN HEAVY SNOW OVERNIGHT. THIS INCLUDES KBIL...KMLS AND KSHR. W OF THIS AREA...EXPECT MVFR AND IFR CONDITIONS. THERE WILL ALSO BE BLOWING SNOW E OF KBIL AND OVER KSHR. THE MOUNTAINS WILL BE OBSCURED. THE SNOW WILL TAPER OFF FROM W TO E DURING THE DAY ON MON WITH CONDITIONS IMPROVING TO MVFR/VFR W OF A KMLS TO PRYOR LINE IN THE MORNING. E OF THIS LINE...EXPECT IFR TO LIFR CONDITIONS IN THE MORNING. THE ENTIRE AREA WILL HAVE MVFR TO VFR CONDITIONS MON AFTERNOON. EXPECT AREAS OF OBSCURATION OVER THE CRAZYS...BEARTOOTHS AND ABSAROKAS. WIDESPREAD OBSCURATION OVER THE NE BIG HORNS WILL DECREASE TO AREAS OF OBSCURATION MON AFTERNOON. ARTHUR && .PRELIMINARY POINT TEMP/POPS... MON TUE WED THU FRI SAT SUN ----------------------------------------------------------- BIL 026/036 025/040 025/045 027/046 027/053 032/056 032/053 +4/S 22/W 33/W 21/B 12/W 22/W 33/W LVM 027/042 025/043 025/046 023/046 027/051 032/052 032/051 +3/O 22/W 22/W 21/B 12/W 22/W 33/W HDN 028/038 023/043 025/046 027/049 028/056 033/059 033/055 +4/S 22/W 33/W 21/B 11/B 11/B 33/W MLS 023/033 021/039 022/042 025/046 028/047 033/057 033/054 +5/S 12/W 22/W 32/W 11/B 11/B 22/W 4BQ 025/034 019/039 022/042 024/045 027/051 032/051 032/052 +9/S 13/W 33/W 32/W 11/B 11/B 23/W BHK 018/027 014/035 016/038 021/042 025/044 030/051 030/050 +9/S 12/W 22/J 32/W 11/B 11/B 22/W SHR 027/035 022/041 023/042 022/044 024/051 029/053 029/051 +7/S 24/W 44/W 22/W 00/B 11/B 23/W && .BYZ WATCHES/WARNINGS/ADVISORIES... MT...WINTER WEATHER ADVISORY IN EFFECT UNTIL 6 PM MDT MONDAY FOR ZONES 29-30-34-35-40-41-64-65. WINTER STORM WARNING IN EFFECT UNTIL 6 PM MDT MONDAY FOR ZONES 31-32-36-38-39-56>58-66. BLIZZARD WARNING IN EFFECT UNTIL 6 PM MDT MONDAY FOR ZONES 33-37. WINTER STORM WARNING IN EFFECT UNTIL 6 AM MDT MONDAY FOR ZONES 67-68. WY...WINTER STORM WARNING IN EFFECT UNTIL 6 PM MDT MONDAY FOR ZONES 98-99. && $$ WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1232 PM CDT SAT MAR 29 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 354 AM CDT SAT MAR 29 2014 A WARM DRY SURGE IS READY TO GO TODAY. THE SOURCE REGION FOR THIS WARM AIR IS THE SOUTH CENTRAL ROCKIES AND THE RAP MODEL SHOWS SOUTHWEST WINDS DRAWING THIS AIR THROUGH THE FCST AREA...GENERALLY ALONG AND WEST OF HIGHWAY 83. NEARLY FULL SUN IS EXPECTED AS THE NEAREST CIRRUS IS OVER THE TETONS AND BIG HORNS. THE GFS HOWEVER SHOWS CIRRUS DEVELOPING THIS AFTN OFF THE LARAMIE RANGE AND THIS IS SUPPORTED BY THE ECM WHICH GENERALLY HAS GOOD SKILL WITH HIGH CLOUDS. STILL...THE SUPER ENSEMBLE TEMPERATURE FORECAST PRODUCES HIGHS IN THE UPPER 60S TO NEAR 70 WHICH WERE MARKED UP TO LOWER 70S IN MANY AREAS GIVEN THE VERY DEEP MIXING SHOWN BY THE RAP MODEL. SOUTHWEST WINDS INCREASE TO 15 TO 25 MPH AND A BLEND OF THE NAM...RAP AND GFS WIND GUST PRODUCTS PRODUCED WIND GUSTS TO 35 MPH. FOR TONIGHT...THE THERMAL RIDGE FORECAST TO MOVE OFF THE ROCKIES TODAY CONTINUES TO BUILD ACROSS THE FORECAST AREA. LOWS SHOULD ONLY FALL TO THE MID 30S TO LOWER 40S WITH DECOUPLING POSSIBLE OVER SOUTHWEST NEB FOR LOCALLY COOLER LOWS GIVEN THE VERY DRY ENVIRONMENTAL CONDITIONS. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 354 AM CDT SAT MAR 29 2014 UPPER LEVEL RIDGE TO BREAK DOWN ON SUNDAY AS AN UPPER TROUGH ADVANCES NORTHEAST FROM THE GREAT BASIN TOWARD THE CENTRAL PLAINS. WITH THE APPROACH OF THE UPPER TROUGH...CYCLOGENESIS WILL COMMENCE OFF THE LEE OF THE ROCKIES WITH SUBSEQUENT DEEPENING OF THE SURFACE LOW THROUGH THE DAY. THE LOW SHOULD REMAIN FOCUSED ALONG OR NEAR THE CHEYENNE RIDGE SUNDAY...WHICH AS IT DEEPENS WILL ALLOW FOR BACKED SURFACE WINDS TO THE SOUTHEAST. DESPITE HIGH TEMPERATURES WELL INTO THE 70S ACROSS THE CENTRAL SANDHILLS AND POINTS SOUTH /MAYBE A FEW 80S AS WELL/...THIS BACKED SURFACE FLOW WILL ALLOW FOR A GREATER MOISTURE TRAJECTORY OFF THE GULF...RATHER THAN THE DIRECT DOWNSLOPE FLOW FROM SOUTH CENTRAL COLORADO. TD/S ARE ANTICIPATED TO RISE SOME...BUT STEEP LOW-MID LEVEL LAPSE RATES WILL CONTINUE TO MIX DRY ALOFT TO THE SURFACE...EFFECTIVELY KEEPING MINIMUM RELATIVE HUMIDITIES NEAR CRITICAL THRESHOLDS. ATTM...SOUTHWEST NEBRASKA AND THE CENTRAL SANDHILLS ARE EXPECTED TO SEE RH IN THE 15 PERCENT RANGE BY EARLY AFTERNOON...BUT SHOULD INCREASE SLIGHTLY TOWARD EVENING. EXTENDING FROM THE LOW WILL BE AN INVERTED SURFACE TROUGH...WHICH WOULD PRODUCE A WEAKNESS IN THE WIND FIELD. AVAILABLE MODEL GUIDANCE DOES NOT SUPPORT RFW WIND CRITERIA ATTM ACROSS THE CENTRAL SANDHILLS. HOWEVER STRONG MIXING DUE TO VERY STEEP LOW-MID LEVEL LAPSE RATES WOULD ALLOW FOR DOWNWARD MOMENTUM TRANSFER. GUSTS IN EXCESS OF 25 MPH ARE INDICATED BY BUFR SOUNDINGS WHERE THE RH MINIMUM EXISTS /SOUTHWEST NEBRASKA. AN ADDITIONAL RED FLAG WARNING IS ANTICIPATED FOR SUNDAY. FOR THIS WILL ISSUE A FIRE WEATHER WATCH WHERE CONFIDENCE IS HIGH /FIRE ZONES 210 AND 219/ ON SEEING RFW CRITERIA. STEEP LAPSE RATES ASSOCIATED WITH AN EASTWARD ADVECTING EML WILL OVERSPREAD MUCH OF THE CENTRAL HIGH PLAINS LATE AFTERNOON/EARLY EVENING RESULTING IN WEAK INSTABILITY ALOFT. HIGH BASED CONVECTION IS POSSIBLE...IF STORMS FIRE...SURFACE TD/T SPREADS OF 40 DEGREES OR WOULD SUGGEST THE POTENTIAL FOR STRONG TSTM OUTFLOW WITH LITTLE RAINFALL. NOT ANTICIPATING A LAL OF 6...BUT TROUBLESOME NONETHELESS. ADDITIONAL CONVECTION IS POSSIBLE INTO THE EVENING HOURS AS THE TROUGH AND ASSOCIATE COLD FRONT CROSS THE CENTRAL PLAINS...BUT ONCE AGAIN MOISTURE INITIALLY IS LACKING...SO WETTING RAINS WILL BE ISOLATED AT BEST. BEYOND SUNDAY EVENING THE FORECAST GETS TRICKY...ESPECIALLY WHEN CONSIDERING THE POTENTIAL IMPACTS OF THE IMPENDING LATE WINTER STORM. ATTM...THERE/S SUFFICIENT AGREEMENT IN THE MODELS TO SUGGEST RAIN CHANGING OVER TO SNOW EARLY ON MONDAY ACROSS OUR NORTHERN ZONES AS THE MAIN TROUGH DRAGS MODIFIED ARCTIC AIR SOUTH INTO THE CWA. IN TERMS OF IMPACTS...TEMPERATURES AT LEAST INITIALLY WILL REMAIN IN THE LOWER 30S...AND GIVEN THE WARM WEEKEND...SNOW MAY STRUGGLE TO ACCUMULATE ON PAVED SURFACES...ESPECIALLY TRUE IF THE BRUNT OF THE SNOW OCCURS AFTER SUNRISE. BUT...WINDS ON THE BACKSIDE OF THE EJECTING SFC LOW WILL BE EXTREMELY GUSTY...WITH THE POTENTIAL OF 35 MPH GUSTS /OR HIGHER/ ACROSS NORTH CENTRAL NEBRASKA ON MONDAY. VISIBILITY WILL BE SIGNIFICANTLY REDUCED WHEN SNOW IS FALLING. WINTER HEADLINES ARE POSSIBLE ON MONDAY ACROSS NORTHERN NEBRASKA...WITH THE GREATEST IMPACTS FOCUSED ALONG AND NORTH OF THE HIGHWAY 20 CORRIDOR. WILL INCREASE POPS IN THIS AREA INTO THE LOW LIKELY RANGE WITH THIS FORECAST ISSUANCE. BEYOND MONDAY...THE PATTERN REMAINS ACTIVE THROUGHOUT THE ENTIRE NEXT WORK WEEK AS QUASI-ZONAL FLOW SLOWLY TRANSITIONS TO SOUTHWESTERLY WITH THE APPROACH OF THE NEXT LONGWAVE WESTERN CONUS TROUGH. THIS PATTERN FAVORS SEASONAL...TO SLIGHTLY BELOW AVERAGE TEMPERATURES THROUGH AT LEAST NEXT THURSDAY. IN ADDITION...AS THE NEXT UPPER TROUGH DIGS ACROSS THE GREAT BASIN MID-WEEK...A COLD FRONT WILL REMAIN FIXED SOUTH OF THE CWA...WHICH WILL GENERALLY PROVIDE FOR UPSLOPE FLOW AND CONSIDERABLE CLOUDINESS EACH DAY. PRECIPITATION WILL REMAIN IN THE FORECAST AS WELL. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 1232 PM CDT SAT MAR 29 2014 VFR CONDITIONS WILL CONTINUE ACROSS WESTERN AND NORTH CENTRAL NEBRASKA THROUGH THE TAF PERIOD. ONE CONCERN HOWEVER IS THE WIND. SOUTHWEST WINDS WILL GUST TO AROUND 25 KTS FOR THE REMAINDER OF THIS AFTERNOON AND INTO THE EVENING BEFORE BECOMING LIGHT AND VARIABLE TONIGHT. SUNDAY MORNING...A WARM FRONT WILL LIFT NORTH ACROSS SOUTHWEST NEBRASKA...BUT NOT QUITE MAKE IT TO KVTN BY 30/18Z. CLOUDS WILL THICKEN AND LOWER TOWARD SUNDAY AFTERNOON FOR BOTH TERMINALS...BUT VFR WILL BE MAINTAINED. && .FIRE WEATHER... ISSUED AT 354 AM CDT SAT MAR 29 2014 THE RAP AND HRRR MODELS SHOW DEWPOINTS FALLING INTO THE TEENS TODAY. THE MODEL CONSENSUS SHOWS SOUTHWEST WINDS INCREASING TO 15 TO 25 MPH THIS AFTERNOON. A BLEND OF THE NAM...RAP AND GFS WIND GUST PRODUCTS PRODUCED GUSTS TO 35 MPH THIS AFTERNOON ALSO. THE SOURCE REGION FOR THIS DRY AIR IS THE SCNTL ROCKIES WHERE DEW POINTS ARE CURRENTLY IN THE SINGLE DIGITS. THE MODELS PRODUCE SOUTHWEST WINDS OFF THE ROCKIES TODAY WHICH WILL CARRY THIS DRY AIR INTO THE FCST AREA WHILE TEMPERATURES RISE INTO THE LOWER 70S FOR RH VALUES FALLING INTO THE SINGLE DIGITS. && .LBF WATCHES/WARNINGS/ADVISORIES... RED FLAG WARNING UNTIL 9 PM CDT /8 PM MDT/ THIS EVENING FOR NEZ204-206-209-210-219. FIRE WEATHER WATCH FROM SUNDAY AFTERNOON THROUGH SUNDAY EVENING FOR NEZ210-219. && $$ SHORT TERM...CDC LONG TERM...JACOBS AVIATION...DS FIRE WEATHER...CDC
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
634 AM CDT SAT MAR 29 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 354 AM CDT SAT MAR 29 2014 A WARM DRY SURGE IS READY TO GO TODAY. THE SOURCE REGION FOR THIS WARM AIR IS THE SOUTH CENTRAL ROCKIES AND THE RAP MODEL SHOWS SOUTHWEST WINDS DRAWING THIS AIR THROUGH THE FCST AREA...GENERALLY ALONG AND WEST OF HIGHWAY 83. NEARLY FULL SUN IS EXPECTED AS THE NEAREST CIRRUS IS OVER THE TETONS AND BIG HORNS. THE GFS HOWEVER SHOWS CIRRUS DEVELOPING THIS AFTN OFF THE LARAMIE RANGE AND THIS IS SUPPORTED BY THE ECM WHICH GENERALLY HAS GOOD SKILL WITH HIGH CLOUDS. STILL...THE SUPER ENSEMBLE TEMPERATURE FORECAST PRODUCES HIGHS IN THE UPPER 60S TO NEAR 70 WHICH WERE MARKED UP TO LOWER 70S IN MANY AREAS GIVEN THE VERY DEEP MIXING SHOWN BY THE RAP MODEL. SOUTHWEST WINDS INCREASE TO 15 TO 25 MPH AND A BLEND OF THE NAM...RAP AND GFS WIND GUST PRODUCTS PRODUCED WIND GUSTS TO 35 MPH. FOR TONIGHT...THE THERMAL RIDGE FORECAST TO MOVE OFF THE ROCKIES TODAY CONTINUES TO BUILD ACROSS THE FORECAST AREA. LOWS SHOULD ONLY FALL TO THE MID 30S TO LOWER 40S WITH DECOUPLING POSSIBLE OVER SOUTHWEST NEB FOR LOCALLY COOLER LOWS GIVEN THE VERY DRY ENVIRONMENTAL CONDITIONS. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 354 AM CDT SAT MAR 29 2014 UPPER LEVEL RIDGE TO BREAK DOWN ON SUNDAY AS AN UPPER TROUGH ADVANCES NORTHEAST FROM THE GREAT BASIN TOWARD THE CENTRAL PLAINS. WITH THE APPROACH OF THE UPPER TROUGH...CYCLOGENESIS WILL COMMENCE OFF THE LEE OF THE ROCKIES WITH SUBSEQUENT DEEPENING OF THE SURFACE LOW THROUGH THE DAY. THE LOW SHOULD REMAIN FOCUSED ALONG OR NEAR THE CHEYENNE RIDGE SUNDAY...WHICH AS IT DEEPENS WILL ALLOW FOR BACKED SURFACE WINDS TO THE SOUTHEAST. DESPITE HIGH TEMPERATURES WELL INTO THE 70S ACROSS THE CENTRAL SANDHILLS AND POINTS SOUTH /MAYBE A FEW 80S AS WELL/...THIS BACKED SURFACE FLOW WILL ALLOW FOR A GREATER MOISTURE TRAJECTORY OFF THE GULF...RATHER THAN THE DIRECT DOWNSLOPE FLOW FROM SOUTH CENTRAL COLORADO. TD/S ARE ANTICIPATED TO RISE SOME...BUT STEEP LOW-MID LEVEL LAPSE RATES WILL CONTINUE TO MIX DRY ALOFT TO THE SURFACE...EFFECTIVELY KEEPING MINIMUM RELATIVE HUMIDITIES NEAR CRITICAL THRESHOLDS. ATTM...SOUTHWEST NEBRASKA AND THE CENTRAL SANDHILLS ARE EXPECTED TO SEE RH IN THE 15 PERCENT RANGE BY EARLY AFTERNOON...BUT SHOULD INCREASE SLIGHTLY TOWARD EVENING. EXTENDING FROM THE LOW WILL BE AN INVERTED SURFACE TROUGH...WHICH WOULD PRODUCE A WEAKNESS IN THE WIND FIELD. AVAILABLE MODEL GUIDANCE DOES NOT SUPPORT RFW WIND CRITERIA ATTM ACROSS THE CENTRAL SANDHILLS. HOWEVER STRONG MIXING DUE TO VERY STEEP LOW-MID LEVEL LAPSE RATES WOULD ALLOW FOR DOWNWARD MOMENTUM TRANSFER. GUSTS IN EXCESS OF 25 MPH ARE INDICATED BY BUFR SOUNDINGS WHERE THE RH MINIMUM EXISTS /SOUTHWEST NEBRASKA. AN ADDITIONAL RED FLAG WARNING IS ANTICIPATED FOR SUNDAY. FOR THIS WILL ISSUE A FIRE WEATHER WATCH WHERE CONFIDENCE IS HIGH /FIRE ZONES 210 AND 219/ ON SEEING RFW CRITERIA. STEEP LAPSE RATES ASSOCIATED WITH AN EASTWARD ADVECTING EML WILL OVERSPREAD MUCH OF THE CENTRAL HIGH PLAINS LATE AFTERNOON/EARLY EVENING RESULTING IN WEAK INSTABILITY ALOFT. HIGH BASED CONVECTION IS POSSIBLE...IF STORMS FIRE...SURFACE TD/T SPREADS OF 40 DEGREES OR WOULD SUGGEST THE POTENTIAL FOR STRONG TSTM OUTFLOW WITH LITTLE RAINFALL. NOT ANTICIPATING A LAL OF 6...BUT TROUBLESOME NONETHELESS. ADDITIONAL CONVECTION IS POSSIBLE INTO THE EVENING HOURS AS THE TROUGH AND ASSOCIATE COLD FRONT CROSS THE CENTRAL PLAINS...BUT ONCE AGAIN MOISTURE INITIALLY IS LACKING...SO WETTING RAINS WILL BE ISOLATED AT BEST. BEYOND SUNDAY EVENING THE FORECAST GETS TRICKY...ESPECIALLY WHEN CONSIDERING THE POTENTIAL IMPACTS OF THE IMPENDING LATE WINTER STORM. ATTM...THERE/S SUFFICIENT AGREEMENT IN THE MODELS TO SUGGEST RAIN CHANGING OVER TO SNOW EARLY ON MONDAY ACROSS OUR NORTHERN ZONES AS THE MAIN TROUGH DRAGS MODIFIED ARCTIC AIR SOUTH INTO THE CWA. IN TERMS OF IMPACTS...TEMPERATURES AT LEAST INITIALLY WILL REMAIN IN THE LOWER 30S...AND GIVEN THE WARM WEEKEND...SNOW MAY STRUGGLE TO ACCUMULATE ON PAVED SURFACES...ESPECIALLY TRUE IF THE BRUNT OF THE SNOW OCCURS AFTER SUNRISE. BUT...WINDS ON THE BACKSIDE OF THE EJECTING SFC LOW WILL BE EXTREMELY GUSTY...WITH THE POTENTIAL OF 35 MPH GUSTS /OR HIGHER/ ACROSS NORTH CENTRAL NEBRASKA ON MONDAY. VISIBILITY WILL BE SIGNIFICANTLY REDUCED WHEN SNOW IS FALLING. WINTER HEADLINES ARE POSSIBLE ON MONDAY ACROSS NORTHERN NEBRASKA...WITH THE GREATEST IMPACTS FOCUSED ALONG AND NORTH OF THE HIGHWAY 20 CORRIDOR. WILL INCREASE POPS IN THIS AREA INTO THE LOW LIKELY RANGE WITH THIS FORECAST ISSUANCE. BEYOND MONDAY...THE PATTERN REMAINS ACTIVE THROUGHOUT THE ENTIRE NEXT WORK WEEK AS QUASI-ZONAL FLOW SLOWLY TRANSITIONS TO SOUTHWESTERLY WITH THE APPROACH OF THE NEXT LONGWAVE WESTERN CONUS TROUGH. THIS PATTERN FAVORS SEASONAL...TO SLIGHTLY BELOW AVERAGE TEMPERATURES THROUGH AT LEAST NEXT THURSDAY. IN ADDITION...AS THE NEXT UPPER TROUGH DIGS ACROSS THE GREAT BASIN MID-WEEK...A COLD FRONT WILL REMAIN FIXED SOUTH OF THE CWA...WHICH WILL GENERALLY PROVIDE FOR UPSLOPE FLOW AND CONSIDERABLE CLOUDINESS EACH DAY. PRECIPITATION WILL REMAIN IN THE FORECAST AS WELL. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 634 AM CDT SAT MAR 29 2014 PATCHY/AREAS OF FOG AND IFR/LIFR ACROSS NCNTL NEB WILL DISPERSE BY 15Z. VFR IS EXPECTED ALL AREAS THEREAFTER THROUGH 12Z SUNDAY. SCATTERED HIGH CLOUDS WILL SPREAD EAST OFF THE CNTL ROCKIES AHEAD OF A DISTURBANCE MOVES THROUGH THE WRN U.S. && .FIRE WEATHER... ISSUED AT 354 AM CDT SAT MAR 29 2014 THE RAP AND HRRR MODELS SHOW DEWPOINTS FALLING INTO THE TEENS TODAY. THE MODEL CONSENSUS SHOWS SOUTHWEST WINDS INCREASING TO 15 TO 25 MPH THIS AFTERNOON. A BLEND OF THE NAM...RAP AND GFS WIND GUST PRODUCTS PRODUCED GUSTS TO 35 MPH THIS AFTERNOON ALSO. THE SOURCE REGION FOR THIS DRY AIR IS THE SCNTL ROCKIES WHERE DEW POINTS ARE CURRENTLY IN THE SINGLE DIGITS. THE MODELS PRODUCE SOUTHWEST WINDS OFF THE ROCKIES TODAY WHICH WILL CARRY THIS DRY AIR INTO THE FCST AREA WHILE TEMPERATURES RISE INTO THE LOWER 70S FOR RH VALUES FALLING INTO THE SINGLE DIGITS. && .LBF WATCHES/WARNINGS/ADVISORIES... RED FLAG WARNING FROM 1 PM CDT /NOON MDT/ THIS AFTERNOON TO 9 PM CDT /8 PM MDT/ THIS EVENING FOR NEZ204-206-209-210-219. FIRE WEATHER WATCH FROM SUNDAY AFTERNOON THROUGH SUNDAY EVENING FOR NEZ210-219. && $$ SHORT TERM...CDC LONG TERM...JACOBS AVIATION...CDC FIRE WEATHER...CDC
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
354 AM CDT SAT MAR 29 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 354 AM CDT SAT MAR 29 2014 A WARM DRY SURGE IS READY TO GO TODAY. THE SOURCE REGION FOR THIS WARM AIR IS THE SOUTH CENTRAL ROCKIES AND THE RAP MODEL SHOWS SOUTHWEST WINDS DRAWING THIS AIR THROUGH THE FCST AREA...GENERALLY ALONG AND WEST OF HIGHWAY 83. NEARLY FULL SUN IS EXPECTED AS THE NEAREST CIRRUS IS OVER THE TETONS AND BIG HORNS. THE GFS HOWEVER SHOWS CIRRUS DEVELOPING THIS AFTN OFF THE LARAMIE RANGE AND THIS IS SUPPORTED BY THE ECM WHICH GENERALLY HAS GOOD SKILL WITH HIGH CLOUDS. STILL...THE SUPER ENSEMBLE TEMPERATURE FORECAST PRODUCES HIGHS IN THE UPPER 60S TO NEAR 70 WHICH WERE MARKED UP TO LOWER 70S IN MANY AREAS GIVEN THE VERY DEEP MIXING SHOWN BY THE RAP MODEL. SOUTHWEST WINDS INCREASE TO 15 TO 25 MPH AND A BLEND OF THE NAM...RAP AND GFS WIND GUST PRODUCTS PRODUCED WIND GUSTS TO 35 MPH. FOR TONIGHT...THE THERMAL RIDGE FORECAST TO MOVE OFF THE ROCKIES TODAY CONTINUES TO BUILD ACROSS THE FORECAST AREA. LOWS SHOULD ONLY FALL TO THE MID 30S TO LOWER 40S WITH DECOUPLING POSSIBLE OVER SOUTHWEST NEB FOR LOCALLY COOLER LOWS GIVEN THE VERY DRY ENVIRONMENTAL CONDITIONS. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 354 AM CDT SAT MAR 29 2014 UPPER LEVEL RIDGE TO BREAK DOWN ON SUNDAY AS AN UPPER TROUGH ADVANCES NORTHEAST FROM THE GREAT BASIN TOWARD THE CENTRAL PLAINS. WITH THE APPROACH OF THE UPPER TROUGH...CYCLOGENESIS WILL COMMENCE OFF THE LEE OF THE ROCKIES WITH SUBSEQUENT DEEPENING OF THE SURFACE LOW THROUGH THE DAY. THE LOW SHOULD REMAIN FOCUSED ALONG OR NEAR THE CHEYENNE RIDGE SUNDAY...WHICH AS IT DEEPENS WILL ALLOW FOR BACKED SURFACE WINDS TO THE SOUTHEAST. DESPITE HIGH TEMPERATURES WELL INTO THE 70S ACROSS THE CENTRAL SANDHILLS AND POINTS SOUTH /MAYBE A FEW 80S AS WELL/...THIS BACKED SURFACE FLOW WILL ALLOW FOR A GREATER MOISTURE TRAJECTORY OFF THE GULF...RATHER THAN THE DIRECT DOWNSLOPE FLOW FROM SOUTH CENTRAL COLORADO. TD/S ARE ANTICIPATED TO RISE SOME...BUT STEEP LOW-MID LEVEL LAPSE RATES WILL CONTINUE TO MIX DRY ALOFT TO THE SURFACE...EFFECTIVELY KEEPING MINIMUM RELATIVE HUMIDITIES NEAR CRITICAL THRESHOLDS. ATTM...SOUTHWEST NEBRASKA AND THE CENTRAL SANDHILLS ARE EXPECTED TO SEE RH IN THE 15 PERCENT RANGE BY EARLY AFTERNOON...BUT SHOULD INCREASE SLIGHTLY TOWARD EVENING. EXTENDING FROM THE LOW WILL BE AN INVERTED SURFACE TROUGH...WHICH WOULD PRODUCE A WEAKNESS IN THE WIND FIELD. AVAILABLE MODEL GUIDANCE DOES NOT SUPPORT RFW WIND CRITERIA ATTM ACROSS THE CENTRAL SANDHILLS. HOWEVER STRONG MIXING DUE TO VERY STEEP LOW-MID LEVEL LAPSE RATES WOULD ALLOW FOR DOWNWARD MOMENTUM TRANSFER. GUSTS IN EXCESS OF 25 MPH ARE INDICATED BY BUFR SOUNDINGS WHERE THE RH MINIMUM EXISTS /SOUTHWEST NEBRASKA. AN ADDITIONAL RED FLAG WARNING IS ANTICIPATED FOR SUNDAY. FOR THIS WILL ISSUE A FIRE WEATHER WATCH WHERE CONFIDENCE IS HIGH /FIRE ZONES 210 AND 219/ ON SEEING RFW CRITERIA. STEEP LAPSE RATES ASSOCIATED WITH AN EASTWARD ADVECTING EML WILL OVERSPREAD MUCH OF THE CENTRAL HIGH PLAINS LATE AFTERNOON/EARLY EVENING RESULTING IN WEAK INSTABILITY ALOFT. HIGH BASED CONVECTION IS POSSIBLE...IF STORMS FIRE...SURFACE TD/T SPREADS OF 40 DEGREES OR WOULD SUGGEST THE POTENTIAL FOR STRONG TSTM OUTFLOW WITH LITTLE RAINFALL. NOT ANTICIPATING A LAL OF 6...BUT TROUBLESOME NONETHELESS. ADDITIONAL CONVECTION IS POSSIBLE INTO THE EVENING HOURS AS THE TROUGH AND ASSOCIATE COLD FRONT CROSS THE CENTRAL PLAINS...BUT ONCE AGAIN MOISTURE INITIALLY IS LACKING...SO WETTING RAINS WILL BE ISOLATED AT BEST. BEYOND SUNDAY EVENING THE FORECAST GETS TRICKY...ESPECIALLY WHEN CONSIDERING THE POTENTIAL IMPACTS OF THE IMPENDING LATE WINTER STORM. ATTM...THERE/S SUFFICIENT AGREEMENT IN THE MODELS TO SUGGEST RAIN CHANGING OVER TO SNOW EARLY ON MONDAY ACROSS OUR NORTHERN ZONES AS THE MAIN TROUGH DRAGS MODIFIED ARCTIC AIR SOUTH INTO THE CWA. IN TERMS OF IMPACTS...TEMPERATURES AT LEAST INITIALLY WILL REMAIN IN THE LOWER 30S...AND GIVEN THE WARM WEEKEND...SNOW MAY STRUGGLE TO ACCUMULATE ON PAVED SURFACES...ESPECIALLY TRUE IF THE BRUNT OF THE SNOW OCCURS AFTER SUNRISE. BUT...WINDS ON THE BACKSIDE OF THE EJECTING SFC LOW WILL BE EXTREMELY GUSTY...WITH THE POTENTIAL OF 35 MPH GUSTS /OR HIGHER/ ACROSS NORTH CENTRAL NEBRASKA ON MONDAY. VISIBILITY WILL BE SIGNIFICANTLY REDUCED WHEN SNOW IS FALLING. WINTER HEADLINES ARE POSSIBLE ON MONDAY ACROSS NORTHERN NEBRASKA...WITH THE GREATEST IMPACTS FOCUSED ALONG AND NORTH OF THE HIGHWAY 20 CORRIDOR. WILL INCREASE POPS IN THIS AREA INTO THE LOW LIKELY RANGE WITH THIS FORECAST ISSUANCE. BEYOND MONDAY...THE PATTERN REMAINS ACTIVE THROUGHOUT THE ENTIRE NEXT WORK WEEK AS QUASI-ZONAL FLOW SLOWLY TRANSITIONS TO SOUTHWESTERLY WITH THE APPROACH OF THE NEXT LONGWAVE WESTERN CONUS TROUGH. THIS PATTERN FAVORS SEASONAL...TO SLIGHTLY BELOW AVERAGE TEMPERATURES THROUGH AT LEAST NEXT THURSDAY. IN ADDITION...AS THE NEXT UPPER TROUGH DIGS ACROSS THE GREAT BASIN MID-WEEK...A COLD FRONT WILL REMAIN FIXED SOUTH OF THE CWA...WHICH WILL GENERALLY PROVIDE FOR UPSLOPE FLOW AND CONSIDERABLE CLOUDINESS EACH DAY. PRECIPITATION WILL REMAIN IN THE FORECAST AS WELL. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 1244 AM CDT SAT MAR 29 2014 LOW CEILINGS IN NORTH CENTRAL NEBRASKA WILL CLEAR OUT AFTER 07Z. THEN...IN CENTRAL AND SOUTHWEST NEBRASKA...PATCHY FOG CAN BE EXPECTED. THE EVENING LBF SOUNDING WAS SHOWING UNIFORM MOISTURE IN THE LAYER JUST ABOVE THE SURFACE AND...WITH TEMPERATURES FALLING TO THE UPPER TEENS OR AROUND 20...THE PROBABILITY OF FOG INCREASES IN THE PLATTE RIVER VALLEY. FOR THE LBF AREA...OPEN WATER ON THE NEARBY WETLANDS WILL PROBABLY FAVOR PATCHY FOG THAT COULD GIVE VISIBILITY OF 1/2SM OR LOWER. HOWEVER...OUR CONFIDENCE IS NOT HIGH THAT IT WILL BE THAT LOW...SO WE WILL KEEP THE PREVAILING AT 3SM BCFG WITH TEMPORARY CONDITIONS TO 1SM. NO LOW OR MIDDLE CLOUDS ARE EXPECTED...SO THE FOG/MIST WILL LIFT OUT FAIRLY QUICKLY AFTER SUNRISE. && .FIRE WEATHER... ISSUED AT 354 AM CDT SAT MAR 29 2014 THE RAP AND HRRR MODELS SHOW DEWPOINTS FALLING INTO THE TEENS TODAY. THE MODEL CONSENSUS SHOWS SOUTHWEST WINDS INCREASING TO 15 TO 25 MPH THIS AFTERNOON. A BLEND OF THE NAM...RAP AND GFS WIND GUST PRODUCTS PRODUCED GUSTS TO 35 MPH THIS AFTERNOON ALSO. THE SOURCE REGION FOR THIS DRY AIR IS THE SCNTL ROCKIES WHERE DEW POINTS ARE CURRENTLY IN THE SINGLE DIGITS. THE MODELS PRODUCE SOUTHWEST WINDS OFF THE ROCKIES TODAY WHICH WILL CARRY THIS DRY AIR INTO THE FCST AREA WHILE TEMPERATURES RISE INTO THE LOWER 70S FOR RH VALUES FALLING INTO THE SINGLE DIGITS. && .LBF WATCHES/WARNINGS/ADVISORIES... RED FLAG WARNING FROM 1 PM CDT /NOON MDT/ THIS AFTERNOON TO 9 PM CDT /8 PM MDT/ THIS EVENING FOR NEZ204-206-209-210-219. FIRE WEATHER WATCH FROM SUNDAY AFTERNOON THROUGH SUNDAY EVENING FOR NEZ210-219. && $$ SHORT TERM...CDC LONG TERM...JACOBS AVIATION...CDC FIRE WEATHER...CDC
AREA FORECAST DISCUSSION
NWS ELKO NV
343 PM PDT SAT MAR 29 2014 .SYNOPSIS...A RAPIDLY DEVELOPING AREA OF LOW PRESSURE AND ASSOCIATED COLD FRONT WILL BRING VALLEY RAIN AND SNOW TO THE REGION TONIGHT THROUGH SUNDAY. A SMALL BREAK BETWEEN SYSTEMS SUNDAY NIGHT BEFORE ANOTHER PACIFIC STORM SYSTEM IMPACTS THE REGION MONDAY AFTERNOON THROUGH TUESDAY...BRINGING ANOTHER ROUND OF VALLEY RAIN AND SNOW. && .SHORT TERM...SATURDAY NIGHT THROUGH TUESDAY. CURRENT RUC ANALYSIS INDICATES A RAPIDLY DEEPENING AREA OF LOW PRESSURE FROM EUREKA TO ELY. THIS LOW PRESSURE IS PROGGED TO MOSTLY STAY STATIONARY AND DEEPEN THROUGH THE NIGHT AS THE TEMPERATURE GRADIENT TIGHTENS. IN ADDITION A DEEP PLUME OF PACIFIC MOISTURE IS STREAMING ACROSS NORTHERN NEVADA...WITH RAIN ALREADY BREAKING OUT ACROSS HUMBOLDT COUNTY. MODELS ARE ALL IN GOOD AGREEMENT BRINGING A WIDESPREAD AREA OF .25 TO .50" OF PRECIPITATION OVER THE REGION OVER THE NEXT 24 HOURS...WITH HIGHER AMOUNTS ACROSS THE MOUNTAINS. THE FORECAST CHALLENGE REMAINS WHEN WILL RAIN CHANGEOVER TO SNOW TONIGHT AND AT WHAT ELEVATION WILL THE SNOW ACCUMULATE AT. IT LOOKS LIKE THE VALLEYS OF HUMBOLDT COUNTY WILL REMAIN MOSTLY RAIN...WITH A MIX OF RAIN AND SNOW TOWARDS THE END OF THE EVENT...BUT NO ACCUMULATIONS. ACROSS ELKO COUNTY AND CENTRAL NEVADA THE CHANCE FOR ACCUMULATING SNOW IS MUCH HIGHER...DUE TO HIGHER ELEVATIONS AND THE BULK OF THE PRECIPITATION FALLING AFTER MIDNIGHT. LOOKS LIKE RAIN WILL CHANGE OVER TO SNOW THIS EVENING ABOVE 5500FT ACROSS NORTHERN ELKO COUNTY...WITH RAIN CHANGING OVER TO SNOW FROM AUSTIN TO SPRING CREEK SOMETIME AFTER MIDNIGHT AS 1000-500MB THICKNESS VALUES FALL BELOW 549DAM. 700MB FGEN FORCING PEAKS FROM AUSTIN TO ELKO AROUND 9Z...BEFORE SLIDING INTO EASTERN ELKO AND WHITE PINE COUNTIES BY SUNDAY MORNING. EXPECTING A MODERATE SNOW- BAND TO DEVELOP ALONG THIS FGEN FORCING AS IT IS VERTICALLY STACKED WITH A BROAD AREA OF 500-300MB UPPER LEVEL LIFT DUE TO A DUAL-CORE JET STREAK CIRCULATION. THIS WILL LEAD TO VERY DEEP LIFT AND A VERY FAVORABLE DENTRITIC GROWTH REGION...THUS EXPECTING HIGH END ADVISORY SNOWFALL AMOUNTS ABOVE 6K WHERE IT WILL BE COLD ENOUGH FOR 12 TO 1 SNOW RATIOS. BELOW 5500 FEET SURFACE TEMPS WILL LEAD TO LOW RATIOS...THUS LOWER SNOWFALL AMOUNTS...BUT A SLUSHY INCH COULD EVEN FALL IN ELKO. THE HIGHEST AMOUNTS OF SNOW IN POPULATED AREAS ARE EXPECTED AT AUSTIN...EUREKA...SPRING CREEK...AND ELY. SUNDAY NIGHT THROUGH TUESDAY. SNOW TAPERS OFF DURING THE DAY ON SUNDAY...BEFORE THE NEXT PACIFIC STORM REACHES THE AREA BY MONDAY AFTERNOON. MODELS HAVE BEEN STRUGGLING WITH THIS SYSTEM...DUE TO THE EVOLUTION OF TWO SEPARATE 500MB CIRCULATIONS. CONFIDENCE IS STILL LOW IN HOW THIS SYSTEM WILL MATERIALIZE OVER THE REGION...BUT WET SNOW IS PROBABLE MONDAY NIGHT INTO TUESDAY MORNING AS A SURFACE LOW DEVELOPS OVER NORTHERN NEVADA AND 500MB HEIGHTS DROP TO 546 DAM. THE BEST CHANCE FOR HEADLINE LEVEL SNOWFALL LOOKS TO BE ACROSS NORTHERN NEVADA AT THIS TIME. .LONG TERM...TUESDAY NIGHT THROUGH NEXT SATURDAY. EMPHASIS ON SHORT TERM AND IMPACTS TO AVIATION, SO FEW CHANGES WERE MADE TO THE LONG TERM GRIDS. LARGE COLD TROUGH LINGERS OVER THE GREAT BASIN TUESDAY NIGHT AND WEDNESDAY, FOR UNSEASONABLY COLD WEATHER FOR EARLY APRIL AND SCATTERED SNOW SHOWERS. ADDITIONAL SNOW AMOUNTS DURING THIS TIME FRAME WILL BE LIGHT, WITH THE LARGEST IMPACT BEING THE COLD. WITH 700 MB TEMPS NEAR -10C, AFTERNOON TEMPERATURES WILL STRUGGLE INTO THE 40S WEDNESDAY, AND NW WINDS WILL MAKE IT FEEL EVEN COLDER. TEMPERATURES WILL MODERATE THURSDAY UNDER WEAK RIDGING, AHEAD OF THE NEXT PACIFIC TROUGH. 12Z ECMWF BRINGS THIS PACIFIC TROUGH INLAND INTO NEVADA IN A WEAKENED STATE ON FRIDAY, WITH SOME RAIN AND SNOW SHOWERS. 12Z GFS MUCH FASTER AND MUCH WEAKER WITH THIS WAVE, IN FACT MEDIUM RANGE SOLUTIONS OF GFS/ECMWF/GEM ARE IN MUCH DISAGREEMENT STARTING ABOUT THURSDAY. SHOWED A GRADUAL WARMING TREND IN THE MAX TEMP GRIDS FRIDAY AND SATURDAY, BUT CONFIDENCE IS LOW. BT && .AVIATION...FOR THE 00Z TAFS...COMPLICATED TAF PACKAGE, WITH SNOW AND WIND IMPACTING AVIATION OPERATIONS THROUGH THE NEXT 24 HOURS. MODEL GUIDANCE AGREES THAT INCLEMENT WEATHER WILL OCCUR AT THE TAF SITES, BUT DIFFER A BIT ON TIMING /WITH THE 12Z GFS A BIT SLOWER/ SO WILL HOLD OFF ON TEMPO GROUPS UNTIL THE EVENT STARTS TO UNFOLD THIS AFTERNOON/EVENING. EXPECT DEGRADED CONDITIONS IN -RA TO BEGIN AT KWMC AROUND 00Z, AND AT KEKO AROUND 03Z. EXPECTING -RA TO CHANGE TO -SN AT BOTH KWMC/KEKO APPROXIMATELY 06Z TONIGHT, WITH VIS/CIG MOST LIKELY FALLING TO IFR/CAT A LANDING MINIMUMS AT KEKO 06-15Z SUN. STRONG COLD FRONT WILL REACH KWMC BY 09Z, AND KEKO BY 12Z, WITH STRONG NW WINDS GUSTING 30-35 KTS AND LIMITED VIS IN -SHSN. SINCE MOST OF THE SNOW IS FALLING AT NIGHT AT KEKO, SOME ACCUMULATIONS ON KEKO RUNWAYS ARE POSSIBLE 06-15Z SUN. FURTHER SOUTH...CYCLOGENESIS EXPECTED NEAR KELY AFTER 00Z, WITH STRONG SW/S WINDS GUSTING 30-40 KTS AT TIMES, AT LEAST THROUGH 06Z. INCLUDED VCTS AT KELY THIS EVENING WITH INSTABILITY PRESENT. STRONG COLD FRONT PASSAGE APPROXIMATELY 12-15Z SUN, WITH AGAIN STRONG NW WINDS OF 20-35 KTS. ACCUMULATING SNOW MOST LIKELY AT KELY 12-18Z SUN, WITH IMPACTS POSSIBLE ON KELY RUNWAYS. AT KTPH...STRONG SW WINDS THIS AFTERNOON AT 20-30 KTS. COLD FRONT ARRIVES AT KTPH AROUND 12Z SUN, WITH VERY STRONG NW WINDS FOLLOWING ITS PASSAGE AT THE KTPH TERMINAL, GUSTING TO 40-45 KTS. LIMITED VIS IN BRIEF -RASN MOST LIKELY AT KTPH 12-18Z SUN, BUT IMPACTS WILL BE MUCH LESS HERE COMPARED TO THE OTHER TERMINALS. BT && .LKN WATCHES/WARNINGS/ADVISORIES... WINTER WEATHER ADVISORY UNTIL 5 PM PDT SUNDAY ABOVE 5500 FEET FOR NORTHERN ELKO COUNTY...NORTHERN LANDER COUNTY AND NORTHERN EUREKA COUNTY...SOUTHWESTERN ELKO COUNTY. WINTER WEATHER ADVISORY FROM 8 PM THIS EVENING TO 5 PM PDT SUNDAY ABOVE 6000 FEET FOR SOUTH CENTRAL ELKO COUNTY...SOUTHERN LANDER COUNTY AND SOUTHERN EUREKA COUNTY...WHITE PINE COUNTY. WIND ADVISORY UNTIL 8 PM PDT THIS EVENING FOR NORTHEASTERN NYE COUNTY...WHITE PINE COUNTY. WINTER STORM WARNING UNTIL 5 PM PDT SUNDAY FOR RUBY MOUNTAINS/EAST HUMBOLDT RANGE. WIND ADVISORY FROM 5 AM TO 5 PM PDT SUNDAY FOR NORTHWESTERN NYE COUNTY. && $$ 95/99/99
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
952 PM EDT SUN MAR 30 2014 .SYNOPSIS... A LATE SEASON WINTER STORM THAT WAS CENTERED OFF THE NEW JERSEY COAST WILL SHIFT FARTHER OUT TO SEA OVERNIGHT. ALL THE SNOW AND MIXED PRECIPITATION WILL TAPER OFF LATE TONIGHT. IN THE MEANTIME...TRAVEL WILL BE HAZARDOUS TONIGHT ACROSS MUCH OF NORTHEAST PENNSYLVANIA AND IN CENTRAL NEW YORK FROM INTERSTATE 81 AND POINTS EAST. AS THIS WINTER STORM EXITS OFF TO THE NORTHEAST COAST, HIGH PRESSURE WILL BUILD IN FOR MONDAY AND TUESDAY WITH MILDER MORE SPRING LIKE WEATHER. HIGH TEMPERATURES WILL CLIMB INTO THE 40S FOR MONDAY, AND POSSIBLY NEAR 60 FOR TUESDAY. && .NEAR TERM /UNTIL 6 AM MONDAY MORNING/... UPDATED AS OF 940 PM... UPGRADED BROOME...SUSQUEHANNA...WYOMING AND NORTHERN WAYNE CO/S TO WINTER STORM WARNING BASED ON SNOWFALL SPOTTER REPORTS. A FEW LOCATIONS IN THESE COUNTIES WILL EXCEED 10 INCHES. MANY REPORTS RECEIVED BETWEEN 5 AND 7 INCHES IN THE WARNING AREA SO WITH PRESENT RADAR TRENDS...BELIEVE MANY AREAS WILL SEE AT LEAST 7 INCHES IN THESE COUNTIES. FARTHER N LESS SNOW WAS REPORTED IN CHENANGO CO AND DELWARE/OTSEGO COUNTIES...TO THE TUNE OF 2-5 INCHES. I CAN SEE A COUPLE MORE INCHES IN THESE PLACES SO WILL STICK WITH ADVY THERE. FARTHER S OF THE WARNING AREA...SNOW IS BECOMING MORE WIDESPREAD BUT NOT CONCENTRATING INTO BANDS. AS THE UPPER LEVEL LOW PULLS AWAY...THE DEFORMATION BAND WILL TAPER DOWN AND WEAKEN...WITH MOST OF THE SNOW TO THE EAST TWD THE POCONOS AND WESTERN CATSKILLS. I THINK WE WILL SEE SNOW AMNTS OF 2-5 INCHES IN THE POCONOS/WESTERN CATSKILLS WITH 1-3 INCHES IN THE VALLEYS. SO WILL CONT ADVY/S IN THE REST OF NE PA AND SULLIVAN CO. PREVIOUS DSCN IS BELOW... WATER VAPOR IMAGERY SHOWS A CLOSED MID TO UPPER LEVEL LOW SPINNING OFF THE NJ COAST. A DEFORMATION ZONE OF LOCALLY HEAVY SNOW HAS SET UP TO THE WEST OF THIS UPPER LEVEL LOW FROM ABT UCA TO NORWICH TO THE CITY OF BINGHAMTON TO AVP. THERE WAS A SECONDARY BAND OF HEAVIER MIXED PRECIP...FROM DELAWARE CO INTO THE POCONOS. WITH MORE SHOWERLY LOOKING PRECIP TO THE S AND E. THIS AREA WAS MAINLY FREEZING RAIN...SLEET AND JUST PLAIN RAIN. THE RAP SHOWS THAT THIS UPPER LEVEL LOW WILL DRIFT EASTWARD BETWEEN 01Z AND 04Z AND THE DEFORMATION ZONE THAT WAS PRESENTLY AT THE WEST EDGE OF THE PRECIP SHIELD WILL WEAKEN. I BELIEVE ANOTHER BAND WILL FORM FARTHER TO THE S AND E AND AFFECT THE WESTERN CATSKILLS INTO PIKE CO/SRN WAYNE BTWN 1 AND 4Z. HOWEVER...THE CYCLONE WAS BECOMING MORE VERTICALLY STACKED AT THIS TIME AND THUS BELIEVE THE HEAVIEST SNOW FROM THIS STORM IN OUR AREA WILL BE OVER. SO HAVE ADJUSTED SNOW AMNTS DOWN A TOUCH FOR SULLIVAN AND PIKE CO/S. FARTHER N AND W...HAVE HAD TO CHASE SNOW AMNTS AS BANDING WAS LEADING TO RAPID SNOW ACCUMULATIONS. BUT AT THE SAME TIME SOME OF THE HIGHER RADAR RETURNS WERE RELATED TO THE MELTING LEVEL AND JUST SLEET AND WET SNOW WAS FALLING WITH LESS ACCUMULATION. SO WE HAVE RELIED HEAVILY ON SPOTTER REPORTS. THANKS TO ALL SPOTTERS WHO HAVE SENT REPORTS IN...THEY HAVE BEEN MOST HELPFUL. WILL CONT WINTER WX ADVY WHERE IT IS IN EFFECT FOR NOW. LIKELY WILL DROP CORTLAND AND TIOGA CO/S BY 9 PM OR SO AS IT LOOKS LIKE THE DEFORMATION BAND HAS HALTED ITS WESTWARD PROGRESS. I WILL WAIT AND SEE ON THIS. REST OF FORECAST AREA TO THE WEST OF THE PRECIP SHIELD WILL BE JUST CLOUDY AND BLUSTERY FOR THE NIGHTTIME HOURS. && .SHORT TERM /6 AM MONDAY MORNING THROUGH WEDNESDAY/... 320 PM UPDATE... HIPRES WL BUILD IN ON MONDAY AS COASTAL STORM RIDES OFF TO THE NORTHEAST TAKING MOISTURE WITH IT. ONLY LINGERING AFFECT WL BE CLOUD CVR VRY EARLY IN THE MRNG BFR DRY AIR MVS IN FM THE NW. SKIES WL BE MOSUNNY AND TEMPS WL HANDILY RISE INTO THE 40S/NR 50 UNDER STRONG MARCH SUN TOMORROW. 500MB HEIGHTS FOR TUESDAY WILL CLIMB TO NR 567DM WITH S/WV RIDGE BUILDING DIRECTLY OVRHD. GIVEN STRONG MARCH SUN HV GONE ABV GUIDANCE NUMBERS WITH HIGHS IN THE U50S/LWR 60S IN THE VLYS. NO WX IS EXPECTED UNTIL NEXT S/WV APPCHS TUE NGT, SPREADING SHOWERS INTO PORTIONS OF THE AREA MAINLY ACRS NRN ZONES. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... 245 PM UPDATE.. SLIGHTLY COOLER WEATHER BUILDS INTO THE AREA WEDNESDAY NIGHT INTO THURSDAY WHICH WILL RETURN TEMPS CLOSER TO SEASONAL NORMS. THE MAIN FEATURE OF INTEREST IN THE EXTENDED WILL BE THE DEVELOPMENT OF A CLOSED UPPER LOW OVER THE UPPER MIDWEST BY FRIDAY. SOME PRECIPITATION, MAINLY RAIN SHOWERS, MAY TRY TO SNEAK INTO THE SOUTHERN PART OF THE CWA LATE THURSDAY ALONG A BOUNDARY. FOR THE MOST PART THOUGH WE STAY PRECIPITATION FREE UNTIL FRIDAY NIGHT WHEN A FRONT ASSOCIATED WITH THE CLOSED LOW MENTIONED ABOVE, MOVES THROUGH. WE ARE TALKING ALMOST AN ENTIRELY RAIN EVENT BUT SOME ENOUGH COLD AIR MAY REMAIN FOR SOME WET SNOW OVER NORTHERN ONEIDA COUNTY FRIDAY NIGHT. PRECIPITATION ENDS SATURDAY AS OUR REGION GETS INTO A DRY SLOT. BEYOND SATURDAY WE COOL BACK TO BELOW NORMAL FOR THE 2ND HALF OF THE WEEKEND INTO EARLY NEXT WEEK AS THE ACTUAL UPPER LOW MOVES JUST TO OUR NORTH. && .AVIATION /02Z MONDAY THROUGH FRIDAY/... 730 PM UPDATE... COMPLEX AVIATION FORECAST THROUGH TONIGHT. GRADUAL IMPROVEMENT MONDAY MORNING. VFR MON AFTN ON. IN GENERAL IFR CIGS AT ITH AND BGM WILL CONTINUE. POSSIBLE IFR AT AVP AND RME IN SNOW UP TO 3Z. SHARP LINE OF SNOW FROM JUST EAST OF RME AND BGM. THIS LINE SLOWING BUT MAY MAKE IT TO BOTH SITES THIS EVE WITH IFR VSBYS. AREA OF SNOW ALSO OVER AVP CONTINUING INTO THE OVERNIGHT BEFORE DYING IN PLACE. MVFR CIGS WITH VSBYS IFR AND MVFR AVP. CIGS WILL REMAIN THE SAME ALL NIGHT BUT AS SNOW ENDS VSBYS WILL IMPROVE TO VFR. AT SYR/ELM/RME MVFR CIGS WILL CONTINUE TONIGHT WITH VFR VSBYS. AT ITH/BGM IFR CIGS CONTINUE ALL NIGHT WITH VFR VSBYS. BGM DUE TO ELEVATION AND ITH DUE TO FETCH OFF CAYUGA LAKE. AFTER 10Z SLOW IMPROVEMENT TO MVFR THEN TO VFR BY 16Z. NORTH WINDS 10 T0 15 KTS WITH HIGHER GUSTS AT BGM AND AVP INTO MONDAY. OUTLOOK... MON NGT THROUGH WED NGT...MAINLY VFR. THUR/FRI...RESTRICTIONS POSSIBLE IN LIGHT RAIN. && .HYDROLOGY... 8 PM UPDATE... FLOOD WATCH CONTINUES ACROSS THE SOUTH AND EAST. CURRENT PRECIP HAS CHANGED TO SNOW AND SLEET. RUNOFF SHOULD BE CUTTING OFF SOON. THIS DUE TO TEMPERATURES AROUND FREEZING AND PRECIP IN FROZEN FORM. MAY BE ABLE TO DROP THE WATCH BY MIDNIGHT. CURRENT FLOODING IS NINEMILE CREEK AT LAKELAND IN ONONDAGA COUNTY AND TIOUGHNIOGA RIVER AT CORTLAND IN CORTLAND COUNTY. BOTH SHOULD REMAIN ABOVE FLOOD STAGE THIS EVENING THEN FALL BELOW MONDAY. NO OTHER POINTS ARE EXPECTED TO FLOOD NOW. NO REPORTS OF ICE JAMS. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...FLOOD WATCH UNTIL 6 AM EDT MONDAY FOR PAZ038>040-043-044-047- 048-072. WINTER WEATHER ADVISORY UNTIL 8 AM EDT MONDAY FOR PAZ038-044- 047-048-072. WINTER STORM WARNING UNTIL 8 AM EDT MONDAY FOR PAZ039-040-043. NY...FLOOD WATCH UNTIL 6 AM EDT MONDAY FOR NYZ036-037-044>046- 055>057-062. WINTER WEATHER ADVISORY UNTIL 8 AM EDT MONDAY FOR NYZ036-037- 045-046-057-062. WINTER STORM WARNING UNTIL 8 AM EDT MONDAY FOR NYZ056. && $$ SYNOPSIS...DJN NEAR TERM...DJN SHORT TERM...PVN LONG TERM...HEDEN AVIATION...TAC HYDROLOGY...
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
813 PM EDT SUN MAR 30 2014 .SYNOPSIS... A LATE SEASON WINTER STORM THAT WAS CENTERED OFF THE NEW JERSEY COAST THIS EVENING WILL SHIFT FARTHER OUT TO SEA OVERNIGHT. ALL THE SNOW AND MIXED PRECIPITATION WILL TAPER OFF AFTER MIDNIGHT. IN THE MEANTIME...TRAVEL WILL BE HAZARDOUS TONIGHT ACROSS MUCH OF NORTHEAST PENNSYLVANIA AND IN CENTRAL NEW YORK FROM INTERSTATE 81 AND POINTS EAST. AS THIS WINTER STORM EXITS OFF TO THE NORTHEAST COAST, HIGH PRESSURE WILL BUILD IN FOR MONDAY AND TUESDAY WITH MILDER MORE SPRING LIKE WEATHER. HIGH TEMPERATURES WILL CLIMB INTO THE 40S FOR MONDAY, AND POSSIBLY NEAR 60 FOR TUESDAY. && .NEAR TERM /UNTIL 6 AM MONDAY MORNING/... WATER VAPOR IMAGERY SHOWS A CLOSED MID TO UPPER LEVEL LOW SPINNING OFF THE NJ COAST. A DEFORMATION ZONE OF LOCALLY HEAVY SNOW HAS SET UP TO THE WEST OF THIS UPPER LEVEL LOW FROM ABT UCA TO NORWICH TO THE CITY OF BINGHAMTON TO AVP. THERE WAS A SECONDARY BAND OF HEAVIER MIXED PRECIP...FROM DELAWARE CO INTO THE POCONOS. WITH MORE SHOWERLY LOOKING PRECIP TO THE S AND E. THIS AREA WAS MAINLY FREEZING RAIN...SLEET AND JUST PLAIN RAIN. THE RAP SHOWS THAT THIS UPPER LEVEL LOW WILL DRIFT EASTWARD BETWEEN 01Z AND 04Z AND THE DEFORMATION ZONE THAT WAS PRESENTLY AT THE WEST EDGE OF THE PRECIP SHIELD WILL WEAKEN. I BELIEVE ANOTHER BAND WILL FORM FARTHER TO THE S AND E AND AFFECT THE WESTERN CATSKILLS INTO PIKE CO/SRN WAYNE BTWN 1 AND 4Z. HOWEVER...THE CYCLONE WAS BECOMING MORE VERTICALLY STACKED AT THIS TIME AND THUS BELIEVE THE HEAVIEST SNOW FROM THIS STORM IN OUR AREA WILL BE OVER. SO HAVE ADJUSTED SNOW AMNTS DOWN A TOUCH FOR SULLIVAN AND PIKE CO/S. FARTHER N AND W...HAVE HAD TO CHASE SNOW AMNTS AS BANDING WAS LEADING TO RAPID SNOW ACCUMULATIONS. BUT AT THE SAME TIME SOME OF THE HIGHER RADAR RETURNS WERE RELATED TO THE MELTING LEVEL AND JUST SLEET AND WET SNOW WAS FALLING WITH LESS ACCUMULATION. SO WE HAVE RELIED HEAVILY ON SPOTTER REPORTS. THANKS TO ALL SPOTTERS WHO HAVE SENT REPORTS IN...THEY HAVE BEEN MOST HELPFUL. WILL CONT WINTER WX ADVY WHERE IT IS IN EFFECT FOR NOW. LIKELY WILL DROP CORTLAND AND TIOGA CO/S BY 9 PM OR SO AS IT LOOKS LIKE THE DEFORMATION BAND HAS HALTED ITS WESTWARD PROGRESS. I WILL WAIT AND SEE ON THIS. REST OF FORECAST AREA TO THE WEST OF THE PRECIP SHIELD WILL BE JUST CLOUDY AND BLUSTERY FOR THE NIGHTTIME HOURS. && .SHORT TERM /6 AM MONDAY MORNING THROUGH WEDNESDAY/... 320 PM UPDATE... HIPRES WL BUILD IN ON MONDAY AS COASTAL STORM RIDES OFF TO THE NORTHEAST TAKING MOISTURE WITH IT. ONLY LINGERING AFFECT WL BE CLOUD CVR VRY EARLY IN THE MRNG BFR DRY AIR MVS IN FM THE NW. SKIES WL BE MOSUNNY AND TEMPS WL HANDILY RISE INTO THE 40S/NR 50 UNDER STRONG MARCH SUN TOMORROW. 500MB HEIGHTS FOR TUESDAY WILL CLIMB TO NR 567DM WITH S/WV RIDGE BUILDING DIRECTLY OVRHD. GIVEN STRONG MARCH SUN HV GONE ABV GUIDANCE NUMBERS WITH HIGHS IN THE U50S/LWR 60S IN THE VLYS. NO WX IS EXPECTED UNTIL NEXT S/WV APPCHS TUE NGT, SPREADING SHOWERS INTO PORTIONS OF THE AREA MAINLY ACRS NRN ZONES. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... 245 PM UPDATE.. SLIGHTLY COOLER WEATHER BUILDS INTO THE AREA WEDNESDAY NIGHT INTO THURSDAY WHICH WILL RETURN TEMPS CLOSER TO SEASONAL NORMS. THE MAIN FEATURE OF INTEREST IN THE EXTENDED WILL BE THE DEVELOPMENT OF A CLOSED UPPER LOW OVER THE UPPER MIDWEST BY FRIDAY. SOME PRECIPITATION, MAINLY RAIN SHOWERS, MAY TRY TO SNEAK INTO THE SOUTHERN PART OF THE CWA LATE THURSDAY ALONG A BOUNDARY. FOR THE MOST PART THOUGH WE STAY PRECIPITATION FREE UNTIL FRIDAY NIGHT WHEN A FRONT ASSOCIATED WITH THE CLOSED LOW MENTIONED ABOVE, MOVES THROUGH. WE ARE TALKING ALMOST AN ENTIRELY RAIN EVENT BUT SOME ENOUGH COLD AIR MAY REMAIN FOR SOME WET SNOW OVER NORTHERN ONEIDA COUNTY FRIDAY NIGHT. PRECIPITATION ENDS SATURDAY AS OUR REGION GETS INTO A DRY SLOT. BEYOND SATURDAY WE COOL BACK TO BELOW NORMAL FOR THE 2ND HALF OF THE WEEKEND INTO EARLY NEXT WEEK AS THE ACTUAL UPPER LOW MOVES JUST TO OUR NORTH. && .AVIATION /00Z MONDAY THROUGH FRIDAY/... 730 PM UPDATE... COMPLEX AVIATION FORECAST THROUGH TONIGHT. GRADUAL IMPROVEMENT MONDAY MORNING. VFR MON AFTN ON. IN GENERAL IFR CIGS AT ITH AND BGM WILL CONTINUE. POSSIBLE IFR AT AVP AND RME IN SNOW UP TO 3Z. SHARP LINE OF SNOW FROM JUST EAST OF RME AND BGM. THIS LINE SLOWING BUT MAY MAKE IT TO BOTH SITES THIS EVE WITH IFR VSBYS. AREA OF SNOW ALSO OVER AVP CONTINUING INTO THE OVERNIGHT BEFORE DYING IN PLACE. MVFR CIGS WITH VSBYS IFR AND MVFR AVP. CIGS WILL REMAIN THE SAME ALL NIGHT BUT AS SNOW ENDS VSBYS WILL IMPROVE TO VFR. AT SYR/ELM/RME MVFR CIGS WILL CONTINUE TONIGHT WITH VFR VSBYS. AT ITH/BGM IFR CIGS CONTINUE ALL NIGHT WITH VFR VSBYS. BGM DUE TO ELEVATION AND ITH DUE TO FETCH OFF CAYUGA LAKE. AFTER 10Z SLOW IMPROVEMENT TO MVFR THEN TO VFR BY 16Z. NORTH WINDS 10 T0 15 KTS WITH HIGHER GUSTS AT BGM AND AVP INTO MONDAY. OUTLOOK... MON NGT THROUGH WED NGT...MAINLY VFR. THUR/FRI...RESTRICTIONS POSSIBLE IN LIGHT RAIN. && .HYDROLOGY... 8 PM UPDATE... FLOOD WATCH CONTINUES ACROSS THE SOUTH AND EAST. CURRENT PRECIP HAS CHANGED TO SNOW AND SLEET. RUNOFF SHOULD BE CUTTING OFF SOON. THIS DUE TO TEMPERATURES AROUND FREEZING AND PRECIP IN FROZEN FORM. MAY BE ABLE TO DROP THE WATCH BY MIDNIGHT. CURRENT FLOODING IS NINEMILE CREEK AT LAKELAND IN ONONDAGA COUNTY AND TIOUGHNIOGA RIVER AT CORTLAND IN CORTLAND COUNTY. BOTH SHOULD REMAIN ABOVE FLOOD STAGE THIS EVENING THEN FALL BELOW MONDAY. NO OTHER POINTS ARE EXPECTED TO FLOOD NOW. NO REPORTS OF ICE JAMS. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...FLOOD WATCH UNTIL 6 AM EDT MONDAY FOR PAZ038>040-043-044-047- 048-072. WINTER WEATHER ADVISORY UNTIL 8 AM EDT MONDAY FOR PAZ038>040- 043-044-047-048-072. NY...FLOOD WATCH UNTIL 6 AM EDT MONDAY FOR NYZ036-037-044>046- 055>057-062. WINTER WEATHER ADVISORY UNTIL 8 AM EDT MONDAY FOR NYZ036-037- 044>046-055>057-062. && $$ SYNOPSIS...DJN NEAR TERM...DJN SHORT TERM...PVN LONG TERM...HEDEN AVIATION...TAC HYDROLOGY...TAC
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
659 PM EDT SAT MAR 29 2014 .SYNOPSIS... A MOISTURE LADEN STORM SYSTEM WILL IMPACT OUR REGION TONIGHT INTO SUNDAY. THIS SYSTEM WILL PRODUCE A MIXTURE OF RAIN...SLEET AND SNOW...WITH SOME ICE ACCUMULATION ACROSS PORTIONS OF EASTERN VERMONT. HEAVY RAINFALL ACROSS SOUTHERN VERMONT...COMBINED WITH MELTING SNOW WILL PRODUCE INCREASED HYDRO CONCERNS OVER THE WEEKEND. && .NEAR TERM /THROUGH SUNDAY/... AS OF 648 PM EDT SATURDAY...SOME MINOR CHANGES WITH THIS UPDATE...MAINLY TO SLOW START TIME OF PRECIPITATION BY A COUPLE OF HOURS. PRECIPITATION HAS MADE IT AS FAR NORTH AS NORTH ADAMS IN MASS. SHOULD SEE IT MOVE INTO PARTS OF SOUTHERN VERMONT OVER THE NEXT 1-2 HOURS...CENTRAL VERMONT AROUND 9 PM...BURLINGTON AREA AROUND 10 PM...AND ACROSS THE ENTIRE NORTH COUNTRY BY AROUND 11 PM. HEAVIEST PRECIP STILL APPEARS IT WILL FALL BETWEEN 06Z AND 12Z. VERTICAL TEMPERATURE PROFILES REMAIN VERY TRICKY WITH NEARLY ISOTHERMAL PROFILE FROM THE SURFACE TO 825-MB CENTERED AROUND 0C. DYNAMIC/EVAPORATIONAL COOLING SHOULD HELP TO COOL THE COLUMN AT LEAST IN HEAVIER PRECIPITATION IN THE ADVISORY AREA AND ESPECIALLY NORTHERN NEW YORK. ONE CAVEAT TO NOTE...LATEST RAP SOLUTIONS ARE CONSIDERABLY WARMER AND WOULD FAVOR MORE RAIN OVER SNOW/SLEET FOR MUCH OF VERMONT...BUT WILL KEEP FORECAST AS IS FOR NOW. PREVIOUS DISCUSSION FROM 402 PM SATURDAY... WINTER WEATHER ADVISORY REMAINS IN EFFECT FOR MIXED PRECIPITATION ACROSS ALL OF THE NORTH COUNTRY EXCEPT WESTERN RUTLAND COUNTY. FLOOD WATCH REMAINS IN EFFECT FOR RUTLAND...WINDSOR...ORANGE...AND WESTERN ADDISON COUNTIES FOR THE POTENTIAL OF MINOR RIVER FLOODING FROM THE COMBINATION OF SNOW MELT...EXPECTED RAINFALL...AND ASSOCIATED RIVER RISES AND ICE JAM THREAT. THERE HAVE BEEN SOME INTERVALS OF SUNSHINE ACROSS SOUTHERN HALF OF VERMONT THIS AFTERNOON...WHILE WHILE LOW CLOUDS HANGING ON ACROSS MUCH OF THE NORTH. MEANWHILE...CLOUDS IN ADVANCE OF OUR NEXT LOW PRESSURE SYSTEM ARE SPREADING INTO SOUTHERN AREAS...WITH PRECIPITATION NOT FAR BEHIND. TEMPS ACROSS THE REGION IN THE UPPER 30S NORTH TO 40S SOUTH AND IN EASTERN VERMONT. LOWER DEWPOINTS TO THE NORTH ACROSS QUEBEC...AND SOME OF THIS AIR WILL ADVECT SOUTH INTO FORECAST AREA TONIGHT WITH LOW LEVEL NORTHERLY FLOW. COMPLICATED TEMPERATURE PROFILE WILL RESULT IN A VARIETY OF PRECIPITATION TYPES TONIGHT INTO SUNDAY...WITH PROBLEMS ENHANCED BY FACT THAT THERE IS PLENTY OF MOISTURE AVAILABLE...SO SOME GENEROUS QPF AMOUNTS ANTICIPATED FOR MUCH OF THE NORTH COUNTRY. A COMPLEX STORM SYSTEM DEVELOPING OVER THE LOWER OHIO VALLEY WILL TRACK EAST TO THE DELMARVA REGION TONIGHT...THEN NORTHEAST TO A POSITION OFF CAPE COD BY MONDAY. THIS MOISTURE LADEN SYSTEM WILL BRING A SIGNIFICANT AMOUNT OF PRECIPITATION TO THE NORTH COUNTRY TONIGHT INTO SUNDAY...WITH QPF AMOUNTS GENERALLY FROM 0.75 INCHES TO 1.5 INCHES. SOME LOCALLY HIGHER AMOUNTS POSSIBLE SOUTHERN VERMONT...AND LOWER AMOUNTS OVER SAINT LAWRENCE VALLEY. THERE WILL ALSO BE A VARIETY OF PRECIPITATION TYPES TO DEAL WITH...AS FORECAST SOUNDINGS CONTINUE TO SHOW A COMPLEX THERMAL PROFILE WITH SURFACE TEMPS NEAR OR A BIT BELOW FREEZING AND A WARM LAYER ABOVE FREEZING MOVING IN ALOFT. OVERALL...LATEST GUIDANCE SUGGESTS LITTLE CHANGE FROM PREVIOUS MODEL RUN. BREAKING IT DOWN BY AREAS... ACROSS NORTHERN NEW YORK...PRECIP WILL BEGIN AS MAINLY SNOW THIS EVENING...THEN MIX WITH SLEET OVERNIGHT THROUGH MID-DAY SUNDAY. SNOW AND SLEET ACCUMULATIONS OF 3-7" WITH A FEW HIGHER AMOUNTS POSSIBLE NORTHERN ADIRONDACKS. FOR THE CHAMPLAIN VALLEY AND THE NORTHERN WESTERN SLOPES OF THE GREENS...PRECIP BEGINS AS SNOW OR MIX THIS EVENING...THEN MOSTLY SNOW/SLEET MIX OVERNIGHT BEFORE CHANGING TO RAIN BY MID-DAY SUNDAY. SNOW AND SLEET ACCUMULATIONS OF 3-5" ARE EXPECTED. ACROSS CENTRAL AND EASTERN VERMONT...PRECIP BEGINS AS SNOW/SLEET/RAIN THIS EVENING...THEN MOSTLY SLEET AND FREEZING DURING THE OVERNIGHT HOURS BEFORE CHANGING TO RAIN BY MID-DAY SUNDAY. SNOW AND SLEET ACCUMULATIONS OF 2-5" ARE EXPECTED...ALONG WITH A TENTH TO QUARTER INCH OF ICE ESPECIALLY ACROSS ELEVATIONS FROM 1-2KFT. FINALLY...ACROSS RUTLAND AND WINDSOR COUNTIES...PRECIP WILL REMAIN MOSTLY RAIN WITH SOME MIX OF SLEET AND FREEZING RAIN ACROSS THE HIGHER ELEVATIONS. THIS AREA WILL SEE THE MOST RAIN DURING THE EVENT PRESENTING SOME HYDRO CONCERNS DUE TO ICE BREAKUP. SEE OUR HYDRO SECTION BELOW FOR MORE INFO ON THAT. && .SHORT TERM /SUNDAY NIGHT THROUGH MONDAY NIGHT/... AS OF 402 PM EDT SATURDAY...FOR SUNDAY NIGHT INTO MONDAY...WE WILL HAVE TO WATCH FOR THE POSSIBILITY OF ANOTHER ROUND OF MIXED PRECIPITATION. THIS DUE TO SHORTWAVE ROTATING AROUND THE SLOWLY DEPARTING UPPER LOW. MODELS HAVE TRENDED FURTHER WEST WITH THE UPPER LOW AND SHORTWAVE...SO CONFIDENCE INCREASING THAT WE WILL AT LEAST SEE SOME LIGHT SLEET AND OR RAIN/FREEZING RAIN/DRIZZLE SUNDAY NIGHT INTO MONDAY. GREATEST CHANCES WILL BE OVER EASTERN ZONES DUE PROXIMITY WITH UPPER LOW. TEMPS MARGINAL FOR SNOW/RAIN OR MIXED PRECIPITATION ONCE AGAIN. LOOK FOR LOWS SUNDAY NIGHT IN THE MID 20S TO LOWER 30S AND HIGHS MONDAY NEAR 40. SLOW IMPROVEMENT MONDAY NIGHT AS THE UPPER LOW EXITS TO THE EAST. && .LONG TERM /TUESDAY THROUGH SATURDAY/... AS OF 325 PM EDT SATURDAY...DRY START TO THE PERIOD TUESDAY BEFORE UPPER LVL TROUGH...ASSOCIATED WITH CLOSED SFC LOW...TRAVELS FROM THE NRN GREAT LAKES NEWD NEAR JAMES BAY BY MID WEDNESDAY. THIS LOW WILL HAVE A WEAK FRONTAL BOUNDARY DRAPED SOUTH...WHICH WILL BRING LOW CHC OF SHOWERS TO THE NORTH COUNTRY TUESDAY NGT INTO WEDNESDAY...AS THIS BOUNDARY WILL HAVE LIMITED MOISTURE AND MAIN UPPER LVL ENERGY WILL BE FAR NORTH OF THE FA. FOR ANY PRECIP THAT DOES OCCUR...TUESDAY NGT WILL SEE SOME SNOW...BUT WARMING TEMPS ON WEDNESDAY WILL TRANSITION SN INTO RA BEFORE TAPERING OFF. ANOTHER SYSTEM APPROACHING FROM CENTRAL USA WILL BRING WARM FRONT TO THE NE LATE THURSDAY INTO FRIDAY. GFS AND ECMWF DIFFER WITH ECMWF PERSISTING WITH RIDGE. THIS WOULD KEEP THREAT OF PRECIP TO OUR SOUTH THRU LATE FRIDAY. MUCH UNCERTAINTY FOR THE LATTER HALF OF THE WEEK GOING INTO THE WKND. TEMPS THROUGHOUT THE PERIOD WILL BE NEAR NORMAL WITH MAX TEMPS IN THE 40S IN THE VALLEYS AND 30S IN THE MTNS. MIN TEMPS WILL BE IN THE U20S-L30S IN THE VALLEYS AND UPPER TEENS TO L20S IN THE MTNS. && .AVIATION /00Z SUNDAY THROUGH THURSDAY/... THROUGH 18Z SUNDAY...AS LOW PRESSURE APPROACHES FROM SW...WARM FRONT WILL BRING MIXED PRECIP TO THE NORTH COUNTRY FROM S TO N TONIGHT. WITH ONSET OF PRECIP...MVFR/IFR CONDITIONS EXPECTED THROUGH SUNDAY MORNING. LLVL NORTHERLY FLOW WITH WARMING SOUTHERLY FLOW ALOFT WILL LEAD TO VRB/CHANGING P-TYPE THROUGHOUT THE NIGHT AND INTO SUNDAY. HEAVIEST PRECIP EXPECTED OVERNIGHT...GENERALLY AFTER 06Z THROUGH 12Z. ANOTHER CONCERN WILL BE GUSTY WINDS AS PRESSURE GRADIENT INCREASES OVERNGT. KRUT EXPECTING MOSTLY RAIN EVENT...AS WARM AIR IS ABLE TO FILTER IN THROUGHOUT THE COLUMN OF AIR. MVFR CONDITIONS EXPECTED WITH NE-E FLOW ALLOWING FOR DOWNSLOPING/SLGTLY DRIER AIR IN LLVL. WINDS WILL BCM GUSTY AROUND 20KTS AFTER 06Z. KMPV WILL SEE MIX OF SNOW AND SLEET AROUND 00Z...WITH SOME WARMING ALOFT OVRNGT ALLOWING FZRA TO MIX IN AFTER 06Z. FURTHER WARMING INTO SUNDAY MORNING WILL LIKELY SEE MIX OF SLEET AND FZRA. IFR CONDITIONS...ESP CIGS...SETTLE IN WITH PRECIP ONSET THROUGH THE TAF PERIOD. THE CPV WILL HAVE SLTLY WARMER TEMPS ALOFT ON THE ERN SIDE...RESULTING IN -SNPL CHANGING TO FZRASNPL AT KBTV OVRNGT. MIX CONTINUES WITH SOME LLVL WARMING PSBL AT KBTV WITH SNPLRA SUNDAY MORNING. KPBG WILL BE COLDER WITH GENERALLY SN AND PL EXPECTED. OVERNGT IFR CONDITIONS EXPECTED AT BOTH SITES...IMPROVING TO MVFR SUNDAY MID-LATE MORNING. KSLK/KMSS EXPECT MOSTLY SNOW...WITH SOME PL MIXING IN AT KSLK. IFR CONDITIONS EXPECTED TO START BTWN 01Z AND 04Z AS COLDER AIR KEEPS ONSET OF PRECIP AS SN...REDUCING VSBYS QUICKLY. LATE MORNING/EARLY AFTN IMPROVEMENT TO MVFR WILL BE SLOW. OUTLOOK 18Z SUNDAY THROUGH THURSDAY... 18Z SUNDAY THROUGH 00Z MONDAY...WIDESPREAD MVFR/IFR IN MIXED PCPN AND/OR RAIN...TAPERING OFF IN COVERAGE AND INTENSITY FROM WEST TO EAST AFTER 18Z. CONFIDENCE LOW ON EASTWARD PROGRESSION OF PCPN AS SEVERAL MODELS KEEP MIXED PCPN OVER EASTERN TERMINALS WELL INTO MONDAY. 00Z MONDAY TO 18Z MONDAY...TRENDING SLOWLY TO VFR FROM WEST TO EAST AS LIGHT RAIN/SNOW TAPERS OFF. BEST SHOT AT CONTINUED LIGHT PCPN AND MVFR/IFR AT ERN TERMINALS OF KMPV/KRUT. AGAIN...HIGHEST CONFIDENCE OF BETTER FLIGHT CONDS AT NRN NY TERMINALS WITH CONTINUED UNCERTAINTY FURTHER EAST. 18Z MONDAY THROUGH 00Z WEDNESDAY...VFR WITH HIGH PRESSURE. 00Z WEDNESDAY THROUGH 00Z THURSDAY...VFR ALTHOUGH SOME BRIEF PERIODS OF MVFR POSSIBLE IN SCATTERED RAIN/SNOW SHOWERS AS COLD FRONT CROSSES REGION. 00Z THURSDAY ONWARD...VFR W/MVFR PSBL LATE THURSDAY AS WARM FRONT APPROACHES FROM SW...BRINGING PRECIP SOUTH TO NORTH. && .HYDROLOGY... AS OF 325 PM EDT SATURDAY...PRECIPITATION WILL BEGIN TO EDGE INTO SOUTHERN VERMONT LATE THIS AFTN...PROGRESSING NORTHWARD THROUGHOUT THE EVENING. THIS PRECIPITATION IS EXPECTED TO CONTINUE THROUGH SUNDAY NIGHT...RESULTING IN OUR SOUTHERN WATERSHEDS RECEIVING THE MOST RAINFALL ON THE ORDER OF 1-2 INCHES. AREAS FURTHER NORTH AND WEST WILL SEE MORE OF A MIXED PRECIPITATION EVENT...WITH LESSER RAINFALL AMOUNTS. WITH SOUTHERN WATERSHEDS RECEIVING MOSTLY RAIN...EXPECT SNOWPACK TO ABSORB SOME OF THIS RAINFALL AS TEMPERATURES WILL GENERALLY BE IN THE MID TO UPPER 30S THROUGHOUT THE EVENT...LEADING TO LIMITED MELTING OF SNOWPACK. ONLY A FEW HUNDREDTHS OF AN INCH OF SNOW WATER MELT PER HOUR EXPECTED ON TOP OF RAINFALL WILL RESULT IN MODEST TO LOCALLY SHARP RISES IN EXCESS OF 4-5 FEET SUNDAY MORNING/AFTERNOON. ENSEMBLE FORECASTS INDICATE NO RIVER FLOODING EXPECTED....BUT WATER LEVEL RISES MAY BE MORE THAN SUFFICIENT TO PRODUCE ICE MOVEMENT AND/OR BREAKUP ACROSS SCATTERED WATERSHEDS. WILL KEEP FLOOD WATCH IN EFFECT FOR CENTRAL AND SOUTHERN VERMONT. && .BTV WATCHES/WARNINGS/ADVISORIES... VT...WINTER WEATHER ADVISORY UNTIL 2 PM EDT SUNDAY FOR VTZ001>010- 012-016>019. FLOOD WATCH THROUGH MONDAY MORNING FOR VTZ009>012-019. NY...WINTER WEATHER ADVISORY UNTIL 2 PM EDT SUNDAY FOR NYZ026>031- 034-035-087. && $$ SYNOPSIS...RJS NEAR TERM...RJS/MUCCILLI SHORT TERM...RJS LONG TERM...KGM AVIATION...KGM HYDROLOGY...KGM
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
641 PM EDT SAT MAR 29 2014 .SYNOPSIS... A COLD FRONT WILL MOVE OFFSHORE LATE TONIGHT. A SURFACE TROUGH WILL LINGER JUST WEST OF THE AREA INTO MONDAY. WEAK HIGH PRESSURE BUILDS OVER THE REGION MONDAY NIGHT AND TUESDAY. THE HIGH WILL MOVE SOUTH OF THE AREA TUESDAY NIGHT AND WEDNESDAY. ANOTHER COLD WILL APPROACH THE AREA BY LATE WEEK. && .NEAR TERM /THROUGH SUNDAY/... AS OF 640 PM SATURDAY...MAIN QUESTION TONIGHT IS HOW TO BEST HANDLE RAIN POTENTIAL. MAIN BAND OF PRECIPITATION HAS MOVED OFFSHORE WITH ONLY SCATTERED SHOWERS NOW OCCURRING OVER THE EASTERN NC. INITIAL THOUGHT WAS TO DECREASE POPS TO CHANCE AND CALL FOR SCATTERED SHOWERS AT LEAST THROUGH THE EVENING HOURS. EYING AREA OF SHOWERS/POSSIBLE THUNDERSTORMS OVER SOUTH CAROLINA WHICH DEVELOPED IN REGION OF CLEARING EARLIER TODAY. THINK THIS ACTIVITY WILL DECREASE IN COVERAGE/INTENSITY WITH LOSS OF HEATING BY THE TIME IT WOULD ARRIVE OVER THE COASTAL PLAIN. THIS IS DEPICTED IN THE LATEST RUN OF THE HRRR MODEL. LATE TONIGHT DRY SLOTTING SHOULD END ANY CHANCE OF PRECIPITATION UNTIL LATER SUNDAY WHEN THE UPPER LEVEL LOW MOVES THROUGH. USED A BLEND OF THE ECMWF/MET MOS FOR LOWS WITH READINGS IN THE UPPER 40S/LOWER 50S EXPECTED. && .SHORT TERM /SUNDAY NIGHT THROUGH 6 PM SUNDAY/... AS OF 315 PM SATURDAY...WILL HAVE A BIT OF A LULL IN PRECIPITATION DURING THE MORNING HOURS ON SUNDAY...BUT AS UPPER LOW CROSSES TO OUR NORTH NEAR THE NORTH CAROLINA/VIRGINIA BORDER...THE STEEP LAPSE RATES AND MODEST MOISTURE WILL LEAD TO A HIGH CHANCE OF SHOWERS SUNDAY AFTERNOON. WITH GOOD COLD AIR ADVECTION...TEMPERATURES WILL ONLY RECOVER ABOUT 5 TO 7 DEGREES AND WILL FOLLOW THE COOLER NAM MOS GUIDANCE SUNDAY SHOWING HIGH TEMPERATURES IN THE LOW/MID 50S WITH GUSTY W/WNW WINDS. && .LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/... AS OF 3 PM SAT...THE LONG TERM PORTION OF THE FORECAST CAN BE SUMMARIZED AS DRYING OUT AND WARMING UP. MADE ONLY MINOR TWEAKS TO THE POPS ENDING THE RAIN SUNDAY NIGHT. SURFACE/UPPER LOW AND ASSOCIATED MOISTURE MOVE OFF TO THE NORTHEAST WITH RIDGING SURFACE AND ALOFT BUILDING IN FROM THE WEST. RIDGING BEGINS TO BREAK DOWN LATE IN THE WEEK AS AN UPPER LOW AND SURFACE COLD FRONT APPROACH FROM THE WEST. THE COLD FRONT WILL MOVE THROUGH FRIDAY NIGHT AND CARRIED A LOW CHANCE POP FOR SHOWERS AND STORMS. DRYING OUT SATURDAY WITH THE FRONT OFF THE COAST AND A SURFACE HIGH BUILDING TO THE NORTHWEST. NORTHWEST FLOW ON MONDAY WILL DIMINISH AND SLOWLY TRANSITION TO A WEST TO SOUTHWEST FLOW BY TUESDAY NIGHT AND CONTINUE INTO FRIDAY. HIGHS THIS WEEK WILL CLIMB WELL INTO THE 70S ACROSS MOST INLAND AREAS BEGINNING TUESDAY AS WINDS BECOME SOUTHERLY. && .AVIATION /22Z SATURDAY THROUGH THURSDAY/... SHORT TERM /TONIGHT AND SUNDAY/... AS OF 640 PM SATURDAY...SOME IFR CEILINGS ARE STILL BEING REPORTED AT THE TAF SITES BUT THINK THE TREND IS FOR IMPROVEMENT AS THE THREAT FOR WIDESPREAD PRECIPITATION IS OVER AND SOME DRYING IS EXPECTED TO MOVE INTO THE AREA LATER THIS EVENING. BASED ON UPSTREAM OBSERVATIONS AND TRENDS IN THE 12Z/18Z NAM FORECAST SOUNDINGS WILL FORECAST CONDITIONS IMPROVING TO MVFR AND CONTINUING FOR MUCH OF TONIGHT THEN A BRIEF PERIOD OF VFR CONDITIONS AROUND 09Z DURING THE PEAK OF DRYING. AN UPPER LOW IS FORECAST TO MOVE ACROSS NC SUNDAY. ASSOCIATED MOISTURE WILL LEAD TO A RETURN TO MVFR CEILINGS 12-14Z WHICH WILL THEN PERSIST FOR MUCH OF THE DAY. THERE COULD ALSO INTERMITTENT LIGHT RAIN OR DRIZZLE AT TIMES. GUSTY SOUTHERLY WINDS TONIGHT WILL BECOME WESTERLY ON SUNDAY. LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/... AS OF 3 PM SAT...IFR/MVFR CONDITIONS SUNDAY NIGHT WILL BECOME VFR ON MONDAY AS MOISTURE EXITS TO THE NORTHEAST AND A SURFACE/UPPER RIDGE BUILDS IN FROM THE WEST. NORTHWEST WINDS SUNDAY NIGHT AND MONDAY WILL BECOME WEST TO SOUTHWEST TUESDAY NIGHT AND CONTINUE THROUGH THURSDAY. MODEL SOUNDINGS INDICATE LATE NIGHT/EARLY MORNING STRATUS/FOG POSSIBLE EACH MORNING WITH VERY LIGHT WINDS AND BOUNDARY LAYER MOISTURE. && .MARINE... SHORT TERM /TONIGHT AND SUNDAY/... AS OF 640 PM SATURDAY...NO CHANGES TO PREVIOUS FORECAST THINKING OTHER THAN TO EXTEND THE ADVISORIES FOR THE SOUNDS THROUGH EARLY MONDAY. GUSTY SE/S WINDS WILL CONTINUE TONIGHT AND HAVE ADDED THE ALBEMARLE SOUND TO THE SMALL CRAFT ADVISORY THAT WILL REMAIN IN EFFECT UNTIL 5 AM SUNDAY. WILL INITIALIZE WINDS AT 20 TO 25 KNOTS FOR ALL WATERS...EXCEPT 25 TO 30 KNOTS OVER THE OREGON INLET TO OCRACOKE LEG WHERE DIAMOND BUOY IS REPORTING GUSTS TO 35 KNOTS AND DUCK IS INDICATING GUSTS TO 30 KNOTS. THESE WINDS SHOULD SETTLE DOWN AFTER MIDNIGHT AS WINDS VEER TO MORE SW LATE. PER LATEST NWPS WAVE MODEL...SEAS OF 9 TO 13 FEET WILL PREVAIL OVER THE NORTHERN AND CENTRAL WATERS WITH GENERALLY 7 TO 10 FEET OVER SOUTHERN PORTIONS...WITH A SLIGHT DROP IN THE MORE WESTERLY FLOW EXPECTED DURING THE DAY ON SUNDAY. LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/... AS OF 3 PM SAT...AN OVERALL IMPROVING TREND SEEN IN MARINE CONDITIONS THROUGH THE LONG TERM. SURFACE/UPPER LOW WILL MOVE OFF TO THE NORTHEAST SUNDAY NIGHT WITH SURFACE/UPPER RIDGE QUICKLY BUILDING IN AND LINGERING FOR MOST OF THE WEEK. SMALL CRAFT CONDITIONS WILL END FROM SOUTH TO NORTH MONDAY AND MONDAY NIGHT. NORTHWEST FLOW SUNDAY NIGHT INTO MONDAY WILL BECOME WEST TO SOUTHWEST TUESDAY NIGHT THROUGH THURSDAY. && .MHX WATCHES/WARNINGS/ADVISORIES... NC...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 11 AM EDT MONDAY FOR AMZ130-135. SMALL CRAFT ADVISORY UNTIL 2 AM EDT TUESDAY FOR AMZ152-154. SMALL CRAFT ADVISORY UNTIL 5 PM EDT MONDAY FOR AMZ156-158. SMALL CRAFT ADVISORY UNTIL 8 PM EDT MONDAY FOR AMZ150. && $$ SYNOPSIS...CTC NEAR TERM...CTC/JME SHORT TERM...CTC LONG TERM...HSA AVIATION...JME/HSA/LEP MARINE...CTC/JME/HSA
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
320 PM EDT SAT MAR 29 2014 .SYNOPSIS... A COLD FRONT WILL MOVE OFFSHORE LATE TONIGHT. A SURFACE TROUGH WILL LINGER JUST WEST OF THE AREA INTO MONDAY. WEAK HIGH PRESSURE BUILDS OVER THE REGION MONDAY NIGHT AND TUESDAY. THE HIGH WILL MOVE SOUTH OF THE AREA TUESDAY NIGHT AND WEDNESDAY. ANOTHER COLD WILL APPROACH THE AREA BY LATE WEEK. && .NEAR TERM /THROUGH TONIGHT/... AS OF 315 PM SATURDAY...BAND OF LIGHT TO MODERATE SHOWERS ACROSS THE CENTRAL AND EASTERN PORTIONS OF THE CWA CURRENTLY. HRRR AND RAP SHOWING DRY SLOTTING AND HAVE DROPPED POPS BACK TO HIGH CHANCE OVER THE FAR WESTERN COUNTIES FOR THIS EVENING. LIKELY POPS WILL CONTINUE OVER EASTERN AREAS THROUGH THE EVENING BEFORE DROPPING EVERYWHERE LATE TONIGHT. INSTABILITY TODAY HAS BEEN LIMITED BY SHOWERS AND CLOUDS AND HAVE KEPT JUST A SLIGHT CHANCE OF THUNDER THRU THE EVENING AS SOME BREAKS HAVE DEVELOPED IN THE CLOUDS FURTHER WEST OVER SOUTH CAROLINA AND SOUTHERN NORTH CAROLINA...BUT WITH IT GETTING LATE IN THE DAY...AGAIN THINK THUNDER WILL BE LIMITED. THINK COLD AIR ADVECTION WILL KICK IN LATE TONIGHT AND FORECAST LOWS IN THE UPPER 40S AND LOWER 50S. && .SHORT TERM /SUNDAY/... AS OF 315 PM SATURDAY...WILL HAVE A BIT OF A LULL IN PRECIPITATION DURING THE MORNING HOURS ON SUNDAY...BUT AS UPPER LOW CROSSES TO OUR NORTH NEAR THE NORTH CAROLINA/VIRGINIA BORDER...THE STEEP LAPSE RATES AND MODEST MOISTURE WILL LEAD TO A HIGH CHANCE OF SHOWERS SUNDAY AFTERNOON. WITH GOOD COLD AIR ADVECTION...TEMPERATURES WILL ONLY RECOVER ABOUT 5 TO 7 DEGREES AND WILL FOLLOW THE COOLER NAM MOS GUIDANCE SUNDAY SHOWING HIGH TEMPERATURES IN THE LOW/MID 50S WITH GUSTY W/WNW WINDS. && .LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/... AS OF 3 PM SAT...THE LONG TERM PORTION OF THE FORECAST CAN BE SUMMARIZED AS DRYING OUT AND WARMING UP. MADE ONLY MINOR TWEAKS TO THE POPS ENDING THE RAIN SUNDAY NIGHT. SURFACE/UPPER LOW AND ASSOCIATED MOISTURE MOVE OFF TO THE NORTHEAST WITH RIDGING SURFACE AND ALOFT BUILDING IN FROM THE WEST. RIDGING BEGINS TO BREAK DOWN LATE IN THE WEEK AS AN UPPER LOW AND SURFACE COLD FRONT APPROACH FROM THE WEST. THE COLD FRONT WILL MOVE THROUGH FRIDAY NIGHT AND CARRIED A LOW CHANCE POP FOR SHOWERS AND STORMS. DRYING OUT SATURDAY WITH THE FRONT OFF THE COAST AND A SURFACE HIGH BUILDING TO THE NORTHWEST. NORTHWEST FLOW ON MONDAY WILL DIMINISH AND SLOWLY TRANSITION TO A WEST TO SOUTHWEST FLOW BY TUESDAY NIGHT AND CONTINUE INTO FRIDAY. HIGHS THIS WEEK WILL CLIMB WELL INTO THE 70S ACROSS MOST INLAND AREAS BEGINNING TUESDAY AS WINDS BECOME SOUTHERLY. && .AVIATION /19Z SATURDAY THROUGH THURSDAY/... SHORT TERM /TONIGHT AND SUNDAY/... AS OF 115 PM SATURDAY...UNPLEASANT FLYING CONDITIONS WILL BE EXPERIENCED...ESPECIALLY DURING THE FIRST HALF OF THE TAF PERIOD. A POTENT LOW PRESSURE SYSTEM WILL CONTINUE TO TRACK FROM THE WEST...BRINGING MODERATE TO HEAVY SHOWERS ACROSS THE SITES THIS AFTERNOON. BY LATE THIS AFTERNOON/EVENING...ACTIVITY SHOULD DIMINISH AS A DRY SLOT/DRIER AIR WORKS INTO THE REGION. WINDS WILL STILL BE GUSTY FROM THE SW THROUGH THE AFTERNOON. CIGS WILL BE EXTREMELY TRICKY WITH A MIX BAG IN TERMS OF CRITERIA CURRENTLY BEING OBSERVED ACROSS THE CAROLINAS. GIVEN THIS...FEEL THE MOST PREDOMINANT AREA OF IFR/LIFR WILL BE ACROSS THE WESTERN TAF SITES WHILE THE COASTAL SITES MAY SEE MORE IN THE WAY OF MVFR/IFR CIGS. FEELING IS THAT LOW CIGS BEING OBSERVED ACROSS THE SOUTH AND WEST WILL ADVECT INLAND THIS AFTERNOON. HOWEVER...DRIER AIR WILL MOVE IN...PERHAPS LIMITING THE DURATION OF LOW CEILINGS. CONDITIONS SHOULD DRAMATICALLY IMPROVE THROUGH THE EARLY MORNING HOURS AS THE MID LEVEL LOW PROPAGATES NORTH OF THE ARE AND WINDS SHIFT TO THE NW. ANTICIPATE CEILING TO RISE AND NW WINDS TO REMAIN GUSTY THROUGHOUT TOMORROW. LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/... AS OF 3 PM SAT...IFR/MVFR CONDITIONS SUNDAY NIGHT WILL BECOME VFR ON MONDAY AS MOISTURE EXITS TO THE NORTHEAST AND A SURFACE/UPPER RIDGE BUILDS IN FROM THE WEST. NORTHWEST WINDS SUNDAY NIGHT AND MONDAY WILL BECOME WEST TO SOUTHWEST TUESDAY NIGHT AND CONTINUE THROUGH THURSDAY. MODEL SOUNDINGS INDICATE LATE NIGHT/EARLY MORNING STRATUS/FOG POSSIBLE EACH MORNING WITH VERY LIGHT WINDS AND BOUNDARY LAYER MOISTURE. && .MARINE... SHORT TERM /TONIGHT AND SUNDAY/... AS OF 320 PM SATURDAY...GUSTY SE/S WINDS WILL CONTINUE TONIGHT AND HAVE ADDED THE ALBEMARLE SOUND TO THE SMALL CRAFT ADVISORY THAT WILL REMAIN IN EFFECT UNTIL 5 AM SUNDAY. WILL INITIALIZE WINDS AT 20 TO 25 KNOTS FOR ALL WATERS...EXCEPT 25 TO 30 KNOTS OVER THE OREGON INLET TO OCRACOKE LEG WHERE DIAMOND BUOY IS REPORTING 29 KNOTS WITH GUSTS TO 33 KNOTS AND DUCK IS UP TO 32 KNOTS WITH GUSTS TO 38 KNOTS. THESE WINDS SHOULD SETTLE DOWN AFTER MIDNIGHT AS WINDS VEER TO MORE SW LATE. PER LATEST WAVEWATCH...SEAS OF 7 TO 10 FEET WILL PREVAIL OVER THE NORTHERN WATERS WITH GENERALLY 5 TO 8 FEET OVER SOUTHERN PORTIONS...WITH A SLIGHT DROP IN THE MORE WESTERLY FLOW DURING THE DAY ON SUNDAY. LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/... AS OF 3 PM SAT...AN OVERALL IMPROVING TREND SEEN IN MARINE CONDITIONS THROUGH THE LONG TERM. SURFACE/UPPER LOW WILL MOVE OFF TO THE NORTHEAST SUNDAY NIGHT WITH SURFACE/UPPER RIDGE QUICKLY BUILDING IN AND LINGERING FOR MOST OF THE WEEK. SMALL CRAFT CONDITIONS WILL END FROM SOUTH TO NORTH MONDAY AND MONDAY NIGHT. NORTHWEST FLOW SUNDAY NIGHT INTO MONDAY WILL BECOME WEST TO SOUTHWEST TUESDAY NIGHT THROUGH THURSDAY. && .MHX WATCHES/WARNINGS/ADVISORIES... NC...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 5 AM EDT SUNDAY FOR AMZ130-135. SMALL CRAFT ADVISORY UNTIL 2 AM EDT TUESDAY FOR AMZ152-154. SMALL CRAFT ADVISORY UNTIL 5 PM EDT MONDAY FOR AMZ156-158. SMALL CRAFT ADVISORY UNTIL 8 PM EDT MONDAY FOR AMZ150. && $$ SYNOPSIS...CTC NEAR TERM...CTC SHORT TERM...CTC LONG TERM...HSA AVIATION...HSA/LEP MARINE...CTC/HSA
AREA FORECAST DISCUSSION
NWS RALEIGH NC
245 PM EDT SAT MAR 29 2014 .SYNOPSIS... A POTENT STORM SYSTEM WILL TRACK EAST ACROSS THE REGION THROUGH SUNDAY AFTERNOON. HIGH PRESSURE WILL BUILD INTO THE CAROLINAS FROM THE WEST LATE SUNDAY THROUGH EARLY NEXT WEEK. && .NEAR TERM /THROUGH SUNDAY/... AS OF 930 AM SATURDAY... DUE TO IMPROVED VISIBILITIES...HAVE CANCELLED THE DENSE FOG ADVISORY IN MOST AREAS EXCEPT FOR THE NORTHERN PIEDMONT /I-85 CORRIDOR FROM CHAPEL HILL TO HENDERSON/ WHERE PATCHY DENSE FOG WILL PERSIST THROUGH ~10 AM. -VINCENT FOR TODAY/TONIGHT: LATEST OBSERVATIONAL DATA AND SHORT-TERM MODEL GUIDANCE GENERALLY SUPPORT OUR EARLIER THINKING... THAT WE`LL SEE A BORDERLINE STRONG/SEVERE EVENT WITH DAMAGING WIND AS A PRIME THREAT LATE TODAY. EXTENT/SEVERITY WILL LIKELY BE LIMITED BY MARGINAL INSTABILITY AND A DELAY IN THE MORE VIGOROUS DYNAMICS UNTIL AFTER THE PEAK INSTABILITY. CURRENTLY... WIDESPREAD RAIN PERSISTS OVER MUCH OF CENTRAL/ERN NC... DRIVEN BY DEEP MOIST UPGLIDE AND LOW LEVEL MASS CONVERGENCE ASSOCIATED WITH A WEAK WAVE PASSING NORTHEAST THROUGH THE AREA... IN THE WARM SECTOR AHEAD OF THE DEEPENING UPPER LOW DIGGING TOWARD THE MID MISS VALLEY. LATEST MODEL RUNS SUGGEST THAT THIS MOIST UPGLIDE WILL PERSIST FOR SEVERAL MORE HOURS BEFORE THE FOCUS SHIFTS TO OUR NORTHEAST... BRINGING A RELATIVE LULL IN COVERAGE (MORE PATCHY THAN THE CURRENT WIDESPREAD COVERAGE) FOR MOST AREAS BY MID MORNING AS OVERALL ASCENT WEAKENS BRIEFLY. THIS SCENARIO IS SUPPORTED BY THE MOST RECENT HRRR RUNS. WILL INDICATE PRECIP CHANCES SLIPPING BACK TO LIKELY WITH A PERIOD OF LOWER QPF FROM SOON AFTER SUNRISE THROUGH MUCH OF THE MORNING... BUT EXPECT THICK LOW-BASED CLOUDS TO PERSIST AREAWIDE. THE LATEST SURFACE ANALYSIS SHOWS SLIGHTLY MORE STABLE AIR OVER THE NW CWA (AND EXTENDING BACK TO THE EASTERN SLOPES OF WRN NC) WHERE THE RAIN IS EXITING... AND THESE AREAS WILL BE SUSCEPTIBLE TO DENSE FOG THROUGH DAYBREAK GIVEN THE LIGHT/CALM WINDS... DAMP GROUND... AND PROXIMITY TO HIGHER TERRAIN TO HELP BLOCK THIS GROWING STABLE POOL. WILL ISSUE A DENSE FOG ADVISORY THIS MORNING FOR THE NW CWA... WHERE 1/4 MI VSBYS ARE QUICKLY BECOMING PERVASIVE. ATTENTION THEN TURNS TO THE MATURE MCS NOW TRACKING THROUGH MS INTO WRN AL (WITH IMPRESSIVE SATELLITE AND RADAR SIGNATURES). ACCORDING TO EXTRAPOLATION AND RECENT RAP/HRRR RUNS... THE MCV EMANATING FROM THIS MCS IS ON PACE TO TRACK NORTHEASTWARD... PASSING THROUGH CENTRAL/ERN NC BETWEEN 18Z AND 23Z TODAY. A FEW FACTORS ARE APPARENT WHICH SHOULD ENHANCE INSTABILITY OVER CENTRAL NC THIS AFTERNOON... INCLUDING SIMPLY THE EXISTENCE OF THE MCV AND ITS SIGNAL ON HIGH-RES MODEL OUTPUT... AN AREA OF RELATIVE DRYING ALOFT (NOTED AT 700 MB ON THE NAM/GFS) TO POTENTIALLY ELEVATE INSTABILITY... WARM NEAR-SURFACE AIR WITH HIGH DEW POINTS (UPPER 50S-LOWER 60S)... AND A ROUGHLY 40 KT SOUTHWESTERLY LOW LEVEL JET EXPECTED TO SWEEP NORTHEAST ACROSS THE ERN HALF OF NC 18Z-00Z TODAY. MODELS STILL INDICATE FAIRLY SKINNY MUCAPE UP TO 500-1000 J/KG MAINLY OVER THE SE CWA FROM 18Z- 03Z (PEAKING 21Z-00Z) WITH LONG STRAIGHT HODOGRAPHS... SUGGESTING A MAINLY WIND THREAT GIVEN SOME DRYING ALOFT. INITIALLY THOUGH -- AND ESPECIALLY IN THE TRIAD -- THESE HODOGRAPHS ARE CURVED ENOUGH TO BRING ABOUT A CONCERN FOR AN ISOLATED TORNADO IF WE CAN GET ENOUGH INSTABILITY DURING THE EARLY AFTERNOON... WITH THE PRIMARY THREAT ALONG THE EDGE OF THE WEAK STABLE POOL. BUT IF THIS PRECEDING RAIN PERSISTS LONG ENOUGH INTO THE DAY... IT COULD LIMIT THIS INSTABILITY. ANOTHER MITIGATING FACTOR IS THE APPARENT SLIGHT TEMPORAL DISCONNECT BETWEEN THESE FAVORABLE SIGNALS AND THE BEST DYNAMIC FORCING FOR ASCENT... WHICH IS EXPECTED TO ARRIVE THIS EVENING/TONIGHT IN THE FORM OF STRONG DPVA AND 150-200 M HEIGHT FALLS... AS WELL AS A 500 MB JET STREAK OF 60+ KTS WHICH STRENGTHENS ON THE SOUTH SIDE OF THE LOW AND NOSES INTO CENTRAL/ERN NC 00Z-06Z. FINALLY... THE LATEST HRRR RUNS SUGGEST THAT THE COLD POOL NOW TRACKING THROUGH AL MAY TRACK MOSTLY ACROSS GA/SC... AND THAT CONVECTIVE DEVELOPMENT OVER NC MAY BE SUBDUED. IN SUMMARY... WHILE THE THREAT OF SEVERE WINDS (AND POSSIBLY AN ISOLATED WEAK TORNADO OR SMALL HAIL REPORT OR TWO) REMAINS OVER OUR SOUTHEAST... A WIDESPREAD SEVERE WEATHER EVENT IS NOT ANTICIPATED. WE MAY SEE ANOTHER NARROW BAND OF MOSTLY SHOWERS THIS EVENING AS THE ACTUAL COLD FRONT SWEEPS EASTWARD... FOLLOWED BY A SW TO NE END TO POPS OVERNIGHT. STILL EXPECT A CYCLOGENESIS PATTERN CLOSE TO A MILLER-B... WITH THE PRIMARY SURFACE LOW DISSIPATING OVER FAR SW VA AS SECONDARY LOW PRESSURE FORMS ALONG A WEAK TRIPLE POINT OVER THE SW NC FOOTHILLS AND THEN TRACKS NE OVER WRN AND NORTH CENTRAL NC INTO SE VA TONIGHT. THE RAPID STRENGTHENING OF THE UPPER LOW AS IT TRACKS OVERHEAD WILL LEAD TO RAPID DEEPENING OF THE SURFACE LOW AND THUS AN INCREASE IN WINDS BEHIND THE COLD FRONT LATE TONIGHT. DESPITE THE LOW LEVEL STABILIZATION... FORECAST SOUNDINGS SUGGEST PLENTY OF LINGERING MOISTURE IN THE 925-700 MB LAYER FOR LINGERING MOSTLY CLOUDY SKIES ESPECIALLY IN THE NORTHERN CWA OVERNIGHT. FOLLOWING HIGH-RES SHORT TERM GUIDANCE... EXPECT HIGHS TODAY FROM MID 60S NW TO MID 70S SE... NO BETTER THAN A 10-15 DEG F DIURNAL RANGE. LOWS TONIGHT 41 NW TO 48 SE. && .SHORT TERM /SUNDAY AND SUNDAY NIGHT/... AS OF 300 PM SATURDAY... THE UPPER LOW WILL ASSUME A NEGATIVE TILT AS IT PIVOTS SLOWLY NORTHEASTWARD ACROSS NC AND VIRGINIA DURING THE DAY ON SUNDAY...MOVING OFF THE DELMARVA COAST SUNDAY EVENING/NIGHT. SOUNDINGS SHOW STRONG COOLING/MOISTENING ALOFT AS THE COLD CORE LOW MOVES THROUGH THE AREA...WITH TEMPERATURES STRUGGLING TOO WARM DURING THE DAY WITH OVERCAST LOW CLOUDS AND RENEWED PRECIP WITHIN A WRAP AROUND PRECIP BAND. HAVE LOWERED FORECAST HIGHS QUITE A BIT...ESPECIALLY ACROSS THE NORTH WHERE HIGHER POPS/QPF IS EXPECTED. HIGHS RANGING FROM NEAR 50 NE TO MID/UPPER 50S ACROSS THE SOUTH/SOUTHWEST...AND EVEN THAT COULD BE TOO WARM IF SOME OF THE WETTER SOLUTIONS VERIFY. DEEPENING SURFACE EXITING THE TIDEWATER COAST SHOULD RESULT IN BREEZY CONDITIONS WITH SUSTAINED NWLY WINDS 15-20KTS...GUSTING TO 30KTS...REMAINING BELOW ADVISORY CRITERIA. PRECIP WILL TAPER OFF AND MOISTURE WILL CLEAR OUT FROM SW TO NE DURING THE EVENING AS THE UPPER LOW SHIFTS OFFSHORE. LOWS IN THE LOWER TO MID 30S NW TO MID/UPPER 30S SE WITH A STEADY 7-10KT BREEZE PREVENTING WIDESPREAD FROST. && .LONG TERM /MONDAY THROUGH SATURDAY/... AS OF 300 PM SATURDAY... TEMPERATURES WILL QUICKLY MODIFY MONDAY WITH STRONG SYNOPTIC SCALE SUBSIDENCE AS S/W RIDGING DEVELOPS ACROSS THE SOUTHEAST AND REMAINS OVER THE AREA THROUGH LATE IN THE WORK WEEK. THIS WILL KEEP THE PRIMARY STORM TRACK WELL NORTH OF THE AREA...THROUGH THE MIDWEST AND GREAT LAKES REGION. THIS WILL SUPPORT DRY CONDITIONS THROUGH THURSDAY. AFTER SEASONABLE HIGHS OF UPPER 60S/LOWER 70S ON MONDAY... EXPECT ABOVE NORMAL TEMPERATURES OF 75-80 WED/THURS. NEXT WEATHER SYSTEM COULD IMPACT THE AREA LATE FRIDAY AND INTO SATURDAY WITH CURRENT MODEL PROJECTION SHOWING A WEAKENING BAND OF CONVECTION ACROSS THE SOUTHEAST...AS IT BECOMES WELL REMOVED FROM THE ATTENDANT S/W TROUGH LIFTING NEWD THROUGH THE GREAT LAKES. IMPACTS/SEVERE THREAT APPEAR MINIMAL AT THIS TIME. && .AVIATION /14Z SATURDAY THROUGH WEDNESDAY/... AS OF 730 AM SATURDAY... POOR AVIATION CONDITIONS ARE EXPECTED TO PERSIST THROUGH AT LEAST 06Z TONIGHT. SOME IMPROVEMENT FROM IFR TO MVFR IS EXPECTED AT INT/GSO TOWARD THE END OF THE TAF VALID PERIOD AT 12Z. A DEEP MOIST FLOW FROM THE SOUTH AND SW... AHEAD OF A STRENGTHENING STORM SYSTEM NOW MOVING THROUGH MS AND WRN TN... WILL BRING IFR/LIFR CONDITIONS AND PERIODS OF MOSTLY LIGHT RAIN THROUGH DAYBREAK. WE SHOULD SEE A BRIEF BREAK OR LULL IN THE WIDESPREAD RAIN THROUGH THE LATE MORNING THROUGH EARLY AFTERNOON HOURS... MOST LIKELY FROM 14Z TO 19Z... BUT CIGS ARE LIKELY TO REMAIN IFR WITH MVFR TO IFR VSBYS DURING THIS TIME... WITH IFR/LIFR CONDITIONS MOST LIKELY AT INT/GSO. THEN STARTING SOON AFTER 19Z... A LINE OF SHOWERS AND THUNDERSTORMS IS EXPECTED TO SWEEP EAST-NORTHEAST THROUGH CENTRAL NC THROUGH THE LATE AFTERNOON/EARLY EVENING HOURS... BRINGING THE POTENTIAL FOR LOCALLY STRONG WIND GUSTS OVER 30 MPH... AND PERHAPS A FEW SEVERE STORMS. THESE STORMS ARE EXPECTED TO EXIT THE AREA TO OUR NORTHEAST AFTER 02Z... HOWEVER THE PASSAGE OF A COLD FRONT WITH AN UPPER LEVEL LOW CLOSE ON ITS HEELS WILL BRING A CONTINUED THREAT OF MVFR-IFR CIGS THROUGH LATE EVENING AND INTO EARLY OVERNIGHT. WINDS WILL SHIFT TO BE FROM THE NW WITH THE COLD FRONT PASSAGE... BETWEEN 02Z AND 04Z AT INT/GSO... BETWEEN 04Z AND 06Z AT RDU.... AND BETWEEN 07Z AND 09Z AT RWI/FAY. LOOKING BEYOND 12Z TONIGHT... MVFR CIGS ARE EXPECTED TO DOMINATE THROUGH 18Z SUN. WINDS WILL BE BRISK AND GUSTY FROM THE NW THROUGHOUT SUNDAY... BRINGING A CROSSWIND THREAT MAINLY AT GSO/RDU. BETWEEN 18Z SUN AND 00Z MON... SLOW WEST-TO-EAST CLEARING IS EXPECTED AS THE UPPER LEVEL LOW MOVES SLOWLY THROUGH THE AREA... WITH AT TREND TO VFR AT INT/GSO/RDU LIKELY BY 00Z... AND AT RWI/FAY BETWEEN 00Z AND 06Z EARLY MON MORNING. VFR CONDITIONS ARE LIKELY FROM LATE SUN NIGHT THROUGH WED AS HIGH PRESSURE BUILDS INTO THE AREA FROM THE WEST. -GIH && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...VINCENT NEAR TERM...VINCENT/HARTFIELD SHORT TERM...CBL LONG TERM...CBL AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS RALEIGH NC
927 AM EDT SAT MAR 29 2014 .SYNOPSIS... A POTENT STORM SYSTEM WILL TRACK EAST ACROSS THE REGION THROUGH SUNDAY AFTERNOON. HIGH PRESSURE WILL BUILD INTO THE CAROLINAS FROM THE WEST LATE SUNDAY THROUGH EARLY NEXT WEEK. && .NEAR TERM /THROUGH SUNDAY/... AS OF 930 AM SATURDAY... DUE TO IMPROVED VISIBILITIES...HAVE CANCELLED THE DENSE FOG ADVISORY IN MOST AREAS EXCEPT FOR THE NORTHERN PIEDMONT /I-85 CORRIDOR FROM CHAPEL HILL TO HENDERSON/ WHERE PATCHY DENSE FOG WILL PERSIST THROUGH ~10 AM. -VINCENT FOR TODAY/TONIGHT: LATEST OBSERVATIONAL DATA AND SHORT-TERM MODEL GUIDANCE GENERALLY SUPPORT OUR EARLIER THINKING... THAT WE`LL SEE A BORDERLINE STRONG/SEVERE EVENT WITH DAMAGING WIND AS A PRIME THREAT LATE TODAY. EXTENT/SEVERITY WILL LIKELY BE LIMITED BY MARGINAL INSTABILITY AND A DELAY IN THE MORE VIGOROUS DYNAMICS UNTIL AFTER THE PEAK INSTABILITY. CURRENTLY... WIDESPREAD RAIN PERSISTS OVER MUCH OF CENTRAL/ERN NC... DRIVEN BY DEEP MOIST UPGLIDE AND LOW LEVEL MASS CONVERGENCE ASSOCIATED WITH A WEAK WAVE PASSING NORTHEAST THROUGH THE AREA... IN THE WARM SECTOR AHEAD OF THE DEEPENING UPPER LOW DIGGING TOWARD THE MID MISS VALLEY. LATEST MODEL RUNS SUGGEST THAT THIS MOIST UPGLIDE WILL PERSIST FOR SEVERAL MORE HOURS BEFORE THE FOCUS SHIFTS TO OUR NORTHEAST... BRINGING A RELATIVE LULL IN COVERAGE (MORE PATCHY THAN THE CURRENT WIDESPREAD COVERAGE) FOR MOST AREAS BY MID MORNING AS OVERALL ASCENT WEAKENS BRIEFLY. THIS SCENARIO IS SUPPORTED BY THE MOST RECENT HRRR RUNS. WILL INDICATE PRECIP CHANCES SLIPPING BACK TO LIKELY WITH A PERIOD OF LOWER QPF FROM SOON AFTER SUNRISE THROUGH MUCH OF THE MORNING... BUT EXPECT THICK LOW-BASED CLOUDS TO PERSIST AREAWIDE. THE LATEST SURFACE ANALYSIS SHOWS SLIGHTLY MORE STABLE AIR OVER THE NW CWA (AND EXTENDING BACK TO THE EASTERN SLOPES OF WRN NC) WHERE THE RAIN IS EXITING... AND THESE AREAS WILL BE SUSCEPTIBLE TO DENSE FOG THROUGH DAYBREAK GIVEN THE LIGHT/CALM WINDS... DAMP GROUND... AND PROXIMITY TO HIGHER TERRAIN TO HELP BLOCK THIS GROWING STABLE POOL. WILL ISSUE A DENSE FOG ADVISORY THIS MORNING FOR THE NW CWA... WHERE 1/4 MI VSBYS ARE QUICKLY BECOMING PERVASIVE. ATTENTION THEN TURNS TO THE MATURE MCS NOW TRACKING THROUGH MS INTO WRN AL (WITH IMPRESSIVE SATELLITE AND RADAR SIGNATURES). ACCORDING TO EXTRAPOLATION AND RECENT RAP/HRRR RUNS... THE MCV EMANATING FROM THIS MCS IS ON PACE TO TRACK NORTHEASTWARD... PASSING THROUGH CENTRAL/ERN NC BETWEEN 18Z AND 23Z TODAY. A FEW FACTORS ARE APPARENT WHICH SHOULD ENHANCE INSTABILITY OVER CENTRAL NC THIS AFTERNOON... INCLUDING SIMPLY THE EXISTENCE OF THE MCV AND ITS SIGNAL ON HIGH-RES MODEL OUTPUT... AN AREA OF RELATIVE DRYING ALOFT (NOTED AT 700 MB ON THE NAM/GFS) TO POTENTIALLY ELEVATE INSTABILITY... WARM NEAR-SURFACE AIR WITH HIGH DEW POINTS (UPPER 50S-LOWER 60S)... AND A ROUGHLY 40 KT SOUTHWESTERLY LOW LEVEL JET EXPECTED TO SWEEP NORTHEAST ACROSS THE ERN HALF OF NC 18Z-00Z TODAY. MODELS STILL INDICATE FAIRLY SKINNY MUCAPE UP TO 500-1000 J/KG MAINLY OVER THE SE CWA FROM 18Z- 03Z (PEAKING 21Z-00Z) WITH LONG STRAIGHT HODOGRAPHS... SUGGESTING A MAINLY WIND THREAT GIVEN SOME DRYING ALOFT. INITIALLY THOUGH -- AND ESPECIALLY IN THE TRIAD -- THESE HODOGRAPHS ARE CURVED ENOUGH TO BRING ABOUT A CONCERN FOR AN ISOLATED TORNADO IF WE CAN GET ENOUGH INSTABILITY DURING THE EARLY AFTERNOON... WITH THE PRIMARY THREAT ALONG THE EDGE OF THE WEAK STABLE POOL. BUT IF THIS PRECEDING RAIN PERSISTS LONG ENOUGH INTO THE DAY... IT COULD LIMIT THIS INSTABILITY. ANOTHER MITIGATING FACTOR IS THE APPARENT SLIGHT TEMPORAL DISCONNECT BETWEEN THESE FAVORABLE SIGNALS AND THE BEST DYNAMIC FORCING FOR ASCENT... WHICH IS EXPECTED TO ARRIVE THIS EVENING/TONIGHT IN THE FORM OF STRONG DPVA AND 150-200 M HEIGHT FALLS... AS WELL AS A 500 MB JET STREAK OF 60+ KTS WHICH STRENGTHENS ON THE SOUTH SIDE OF THE LOW AND NOSES INTO CENTRAL/ERN NC 00Z-06Z. FINALLY... THE LATEST HRRR RUNS SUGGEST THAT THE COLD POOL NOW TRACKING THROUGH AL MAY TRACK MOSTLY ACROSS GA/SC... AND THAT CONVECTIVE DEVELOPMENT OVER NC MAY BE SUBDUED. IN SUMMARY... WHILE THE THREAT OF SEVERE WINDS (AND POSSIBLY AN ISOLATED WEAK TORNADO OR SMALL HAIL REPORT OR TWO) REMAINS OVER OUR SOUTHEAST... A WIDESPREAD SEVERE WEATHER EVENT IS NOT ANTICIPATED. WE MAY SEE ANOTHER NARROW BAND OF MOSTLY SHOWERS THIS EVENING AS THE ACTUAL COLD FRONT SWEEPS EASTWARD... FOLLOWED BY A SW TO NE END TO POPS OVERNIGHT. STILL EXPECT A CYCLOGENESIS PATTERN CLOSE TO A MILLER-B... WITH THE PRIMARY SURFACE LOW DISSIPATING OVER FAR SW VA AS SECONDARY LOW PRESSURE FORMS ALONG A WEAK TRIPLE POINT OVER THE SW NC FOOTHILLS AND THEN TRACKS NE OVER WRN AND NORTH CENTRAL NC INTO SE VA TONIGHT. THE RAPID STRENGTHENING OF THE UPPER LOW AS IT TRACKS OVERHEAD WILL LEAD TO RAPID DEEPENING OF THE SURFACE LOW AND THUS AN INCREASE IN WINDS BEHIND THE COLD FRONT LATE TONIGHT. DESPITE THE LOW LEVEL STABILIZATION... FORECAST SOUNDINGS SUGGEST PLENTY OF LINGERING MOISTURE IN THE 925-700 MB LAYER FOR LINGERING MOSTLY CLOUDY SKIES ESPECIALLY IN THE NORTHERN CWA OVERNIGHT. FOLLOWING HIGH-RES SHORT TERM GUIDANCE... EXPECT HIGHS TODAY FROM MID 60S NW TO MID 70S SE... NO BETTER THAN A 10-15 DEG F DIURNAL RANGE. LOWS TONIGHT 41 NW TO 48 SE. FOR SUNDAY: EXPECT MOSTLY CLOUDY SKIES TO HOLD PARTICULARLY OVER THE NRN CWA AS THE LOW ALOFT SHIFTS OVER THE REGION. THE DEEPENING SURFACE LOW JUST TO OUR NE WILL GENERATE A TIGHT MSLP GRADIENT ACROSS NC... AND EXPECT WINDS TO BE SUSTAINED FROM THE WNW OR NW AT 15-20 MPH (HIGHEST IN THE WEST WHERE SUBSIDENCE WILL BE STRONGEST WITHIN 100-120 M HEIGHT RISES... AND LOWER NE WHERE MIXING HEIGHTS WILL BE LOWER)... WITH GUSTS OF 20-30 MPH... BELOW WIND ADVISORY CRITERIA BUT THIS RISK WILL STILL NEED TO BE WATCHED. THE LOW LEVELS DO DRY OUT WITH DOWNSLOPE FLOW BUT THIS RELATIVELY DRY LAYER WILL BE SHALLOW... AND WE MAY STILL SEE SOME ISOLATED PATCHY LIGHT RAIN OVER THE NRN CWA IN THE MORNING INTO EARLY AFTERNOON. WITH PLENTIFUL CLOUDINESS... BRISK NW WINDS... COLD AIR ADVECTION... AND LOW LEVEL THICKNESSES EXPECTED TO BE AROUND 30 M BELOW NORMAL... EXPECT CHILLY HIGHS FROM THE UPPER 50S TO LOWER 60S... A SLIGHT DOWNWARD BUMP FROM EARLIER FORECAST HIGHS. -GIH && .SHORT TERM /SUNDAY NIGHT THROUGH MONDAY NIGHT/... AS OF 330 AM SATURDAY... AS THE UPPER LOW OVER THE DELMARVA LATE SUNDAY DEPARTS OFF TO THE NORTHEAST...CLOUD COVER ASSOCIATED WITH ITS COMMA HEAD WRAP AROUND MOISTURE WILL DIMINISH BY MIDNIGHT. CLEARING SKIES AND SLOWLY WEAKENING WINDS WILL ALLOW TEMPS TO DIP INTO THE 30S. BASED ON SOME GUIDANCE...ITS POSSIBLE THAT SOME AREAS OVER THE WESTERN PIEDMONT WILL APPROACH FREEZING BY MONDAY MORNING. RIGHT NOW IT APPEARS A LIGHT WIND AND DRYING WILL PREVENT WIDESPREAD FROST. THE SHOT OF COLDER AIR LOOKS TO BE VERY BRIEF AS A SHORTWAVE RIDGE AND SURFACE HIGH PRESSURE BUILD OVER THE REGION...AND BEGIN AN EVOLUTION INTO A PERSISTENT RIDGE OVER THE SOUTHEAST US. WITH A LIGHT NORTHWEST WIND AND NEUTRAL THERMAL ADVECTION...LOW LEVEL THICKNESSES AROUND 1320M MONDAY MORNING SUPPORT MET MOS GUIDANCE MORE SO THAN THE MAV MOS...UPPER 60S NORTHEAST TO AROUND 70 SOUTHWEST. LOWS MONDAY NIGHT 39-44. && .LONG TERM /TUESDAY THROUGH FRIDAY/... AS OF 330 AM SATURDAY... A RIDGE WILL DEVELOP OVER THE SOUTHEAST BY TUESDAY IS IS FORECAST TO PERSIST THROUGH MUCH OF THE WEEK. THE PRIMARY STORM TRACK WILL BE THROUGH THE MIDWEST AND GREAT LAKES REGION...WITH A WEAK FRONT EXPECTED TO MOVE INTO THE MID-ATLANTIC STATES LATE TUESDAY AND THEN WASH OUT WITHOUT HAVING MUCH...IF ANY IMPACT ON CENTRAL NC. MEDIUM RANGE MODELS SHOW THE RIDGE HOLDING STRONG UNTIL LATE IN THE WEEK...WHEN THE RIDGE FINALLY BREAKS DOWN AND A FRONTAL ZONE PUSHES EAST INTO CENTRAL NC FRIDAY/FRIDAY NIGHT. THIS PATTERN SUPPORTS A MUCH WARMER PERIOD FOR CENTRAL NC...WITH THICKNESSES AS MUCH AS 20-30M ABOVE NORMAL AND HIGHS IN THE 70S OR EVEN 80 IN THE SOUTHEAST BY WED/THURS. && .AVIATION /14Z SATURDAY THROUGH WEDNESDAY/... AS OF 730 AM SATURDAY... POOR AVIATION CONDITIONS ARE EXPECTED TO PERSIST THROUGH AT LEAST 06Z TONIGHT. SOME IMPROVEMENT FROM IFR TO MVFR IS EXPECTED AT INT/GSO TOWARD THE END OF THE TAF VALID PERIOD AT 12Z. A DEEP MOIST FLOW FROM THE SOUTH AND SW... AHEAD OF A STRENGTHENING STORM SYSTEM NOW MOVING THROUGH MS AND WRN TN... WILL BRING IFR/LIFR CONDITIONS AND PERIODS OF MOSTLY LIGHT RAIN THROUGH DAYBREAK. WE SHOULD SEE A BRIEF BREAK OR LULL IN THE WIDESPREAD RAIN THROUGH THE LATE MORNING THROUGH EARLY AFTERNOON HOURS... MOST LIKELY FROM 14Z TO 19Z... BUT CIGS ARE LIKELY TO REMAIN IFR WITH MVFR TO IFR VSBYS DURING THIS TIME... WITH IFR/LIFR CONDITIONS MOST LIKELY AT INT/GSO. THEN STARTING SOON AFTER 19Z... A LINE OF SHOWERS AND THUNDERSTORMS IS EXPECTED TO SWEEP EAST-NORTHEAST THROUGH CENTRAL NC THROUGH THE LATE AFTERNOON/EARLY EVENING HOURS... BRINGING THE POTENTIAL FOR LOCALLY STRONG WIND GUSTS OVER 30 MPH... AND PERHAPS A FEW SEVERE STORMS. THESE STORMS ARE EXPECTED TO EXIT THE AREA TO OUR NORTHEAST AFTER 02Z... HOWEVER THE PASSAGE OF A COLD FRONT WITH AN UPPER LEVEL LOW CLOSE ON ITS HEELS WILL BRING A CONTINUED THREAT OF MVFR-IFR CIGS THROUGH LATE EVENING AND INTO EARLY OVERNIGHT. WINDS WILL SHIFT TO BE FROM THE NW WITH THE COLD FRONT PASSAGE... BETWEEN 02Z AND 04Z AT INT/GSO... BETWEEN 04Z AND 06Z AT RDU.... AND BETWEEN 07Z AND 09Z AT RWI/FAY. LOOKING BEYOND 12Z TONIGHT... MVFR CIGS ARE EXPECTED TO DOMINATE THROUGH 18Z SUN. WINDS WILL BE BRISK AND GUSTY FROM THE NW THROUGHOUT SUNDAY... BRINGING A CROSSWIND THREAT MAINLY AT GSO/RDU. BETWEEN 18Z SUN AND 00Z MON... SLOW WEST-TO-EAST CLEARING IS EXPECTED AS THE UPPER LEVEL LOW MOVES SLOWLY THROUGH THE AREA... WITH AT TREND TO VFR AT INT/GSO/RDU LIKELY BY 00Z... AND AT RWI/FAY BETWEEN 00Z AND 06Z EARLY MON MORNING. VFR CONDITIONS ARE LIKELY FROM LATE SUN NIGHT THROUGH WED AS HIGH PRESSURE BUILDS INTO THE AREA FROM THE WEST. -GIH && .RAH WATCHES/WARNINGS/ADVISORIES... DENSE FOG ADVISORY UNTIL 10 AM EDT THIS MORNING FOR NCZ007>009- 024-025. && $$ SYNOPSIS...VINCENT NEAR TERM...VINCENT/HARTFIELD SHORT TERM...SMITH LONG TERM...SMITH AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS RALEIGH NC
730 AM EDT SAT MAR 29 2014 .SYNOPSIS...A STRONG STORM SYSTEM WILL TRACK EASTWARD THROUGH THE REGION TODAY THROUGH SUNDAY. HIGH PRESSURE WILL BUILD INTO THE AREA SUNDAY NIGHT THROUGH TUESDAY. && .NEAR TERM /TODAY THROUGH SUNDAY/... AS OF 300 AM SATURDAY... FOR TODAY/TONIGHT: LATEST OBSERVATIONAL DATA AND SHORT-TERM MODEL GUIDANCE GENERALLY SUPPORT OUR EARLIER THINKING... THAT WE`LL SEE A BORDERLINE STRONG/SEVERE EVENT WITH DAMAGING WIND AS A PRIME THREAT LATE TODAY. EXTENT/SEVERITY WILL LIKELY BE LIMITED BY MARGINAL INSTABILITY AND A DELAY IN THE MORE VIGOROUS DYNAMICS UNTIL AFTER THE PEAK INSTABILITY. CURRENTLY... WIDESPREAD RAIN PERSISTS OVER MUCH OF CENTRAL/ERN NC... DRIVEN BY DEEP MOIST UPGLIDE AND LOW LEVEL MASS CONVERGENCE ASSOCIATED WITH A WEAK WAVE PASSING NORTHEAST THROUGH THE AREA... IN THE WARM SECTOR AHEAD OF THE DEEPENING UPPER LOW DIGGING TOWARD THE MID MISS VALLEY. LATEST MODEL RUNS SUGGEST THAT THIS MOIST UPGLIDE WILL PERSIST FOR SEVERAL MORE HOURS BEFORE THE FOCUS SHIFTS TO OUR NORTHEAST... BRINGING A RELATIVE LULL IN COVERAGE (MORE PATCHY THAN THE CURRENT WIDESPREAD COVERAGE) FOR MOST AREAS BY MID MORNING AS OVERALL ASCENT WEAKENS BRIEFLY. THIS SCENARIO IS SUPPORTED BY THE MOST RECENT HRRR RUNS. WILL INDICATE PRECIP CHANCES SLIPPING BACK TO LIKELY WITH A PERIOD OF LOWER QPF FROM SOON AFTER SUNRISE THROUGH MUCH OF THE MORNING... BUT EXPECT THICK LOW-BASED CLOUDS TO PERSIST AREAWIDE. THE LATEST SURFACE ANALYSIS SHOWS SLIGHTLY MORE STABLE AIR OVER THE NW CWA (AND EXTENDING BACK TO THE EASTERN SLOPES OF WRN NC) WHERE THE RAIN IS EXITING... AND THESE AREAS WILL BE SUSCEPTIBLE TO DENSE FOG THROUGH DAYBREAK GIVEN THE LIGHT/CALM WINDS... DAMP GROUND... AND PROXIMITY TO HIGHER TERRAIN TO HELP BLOCK THIS GROWING STABLE POOL. WILL ISSUE A DENSE FOG ADVISORY THIS MORNING FOR THE NW CWA... WHERE 1/4 MI VSBYS ARE QUICKLY BECOMING PERVASIVE. ATTENTION THEN TURNS TO THE MATURE MCS NOW TRACKING THROUGH MS INTO WRN AL (WITH IMPRESSIVE SATELLITE AND RADAR SIGNATURES). ACCORDING TO EXTRAPOLATION AND RECENT RAP/HRRR RUNS... THE MCV EMANATING FROM THIS MCS IS ON PACE TO TRACK NORTHEASTWARD... PASSING THROUGH CENTRAL/ERN NC BETWEEN 18Z AND 23Z TODAY. A FEW FACTORS ARE APPARENT WHICH SHOULD ENHANCE INSTABILITY OVER CENTRAL NC THIS AFTERNOON... INCLUDING SIMPLY THE EXISTENCE OF THE MCV AND ITS SIGNAL ON HIGH-RES MODEL OUTPUT... AN AREA OF RELATIVE DRYING ALOFT (NOTED AT 700 MB ON THE NAM/GFS) TO POTENTIALLY ELEVATE INSTABILITY... WARM NEAR-SURFACE AIR WITH HIGH DEW POINTS (UPPER 50S-LOWER 60S)... AND A ROUGHLY 40 KT SOUTHWESTERLY LOW LEVEL JET EXPECTED TO SWEEP NORTHEAST ACROSS THE ERN HALF OF NC 18Z-00Z TODAY. MODELS STILL INDICATE FAIRLY SKINNY MUCAPE UP TO 500-1000 J/KG MAINLY OVER THE SE CWA FROM 18Z- 03Z (PEAKING 21Z-00Z) WITH LONG STRAIGHT HODOGRAPHS... SUGGESTING A MAINLY WIND THREAT GIVEN SOME DRYING ALOFT. INITIALLY THOUGH -- AND ESPECIALLY IN THE TRIAD -- THESE HODOGRAPHS ARE CURVED ENOUGH TO BRING ABOUT A CONCERN FOR AN ISOLATED TORNADO IF WE CAN GET ENOUGH INSTABILITY DURING THE EARLY AFTERNOON... WITH THE PRIMARY THREAT ALONG THE EDGE OF THE WEAK STABLE POOL. BUT IF THIS PRECEDING RAIN PERSISTS LONG ENOUGH INTO THE DAY... IT COULD LIMIT THIS INSTABILITY. ANOTHER MITIGATING FACTOR IS THE APPARENT SLIGHT TEMPORAL DISCONNECT BETWEEN THESE FAVORABLE SIGNALS AND THE BEST DYNAMIC FORCING FOR ASCENT... WHICH IS EXPECTED TO ARRIVE THIS EVENING/TONIGHT IN THE FORM OF STRONG DPVA AND 150-200 M HEIGHT FALLS... AS WELL AS A 500 MB JET STREAK OF 60+ KTS WHICH STRENGTHENS ON THE SOUTH SIDE OF THE LOW AND NOSES INTO CENTRAL/ERN NC 00Z-06Z. FINALLY... THE LATEST HRRR RUNS SUGGEST THAT THE COLD POOL NOW TRACKING THROUGH AL MAY TRACK MOSTLY ACROSS GA/SC... AND THAT CONVECTIVE DEVELOPMENT OVER NC MAY BE SUBDUED. IN SUMMARY... WHILE THE THREAT OF SEVERE WINDS (AND POSSIBLY AN ISOLATED WEAK TORNADO OR SMALL HAIL REPORT OR TWO) REMAINS OVER OUR SOUTHEAST... A WIDESPREAD SEVERE WEATHER EVENT IS NOT ANTICIPATED. WE MAY SEE ANOTHER NARROW BAND OF MOSTLY SHOWERS THIS EVENING AS THE ACTUAL COLD FRONT SWEEPS EASTWARD... FOLLOWED BY A SW TO NE END TO POPS OVERNIGHT. STILL EXPECT A CYCLOGENESIS PATTERN CLOSE TO A MILLER-B... WITH THE PRIMARY SURFACE LOW DISSIPATING OVER FAR SW VA AS SECONDARY LOW PRESSURE FORMS ALONG A WEAK TRIPLE POINT OVER THE SW NC FOOTHILLS AND THEN TRACKS NE OVER WRN AND NORTH CENTRAL NC INTO SE VA TONIGHT. THE RAPID STRENGTHENING OF THE UPPER LOW AS IT TRACKS OVERHEAD WILL LEAD TO RAPID DEEPENING OF THE SURFACE LOW AND THUS AN INCREASE IN WINDS BEHIND THE COLD FRONT LATE TONIGHT. DESPITE THE LOW LEVEL STABILIZATION... FORECAST SOUNDINGS SUGGEST PLENTY OF LINGERING MOISTURE IN THE 925-700 MB LAYER FOR LINGERING MOSTLY CLOUDY SKIES ESPECIALLY IN THE NORTHERN CWA OVERNIGHT. FOLLOWING HIGH-RES SHORT TERM GUIDANCE... EXPECT HIGHS TODAY FROM MID 60S NW TO MID 70S SE... NO BETTER THAN A 10-15 DEG F DIURNAL RANGE. LOWS TONIGHT 41 NW TO 48 SE. FOR SUNDAY: EXPECT MOSTLY CLOUDY SKIES TO HOLD PARTICULARLY OVER THE NRN CWA AS THE LOW ALOFT SHIFTS OVER THE REGION. THE DEEPENING SURFACE LOW JUST TO OUR NE WILL GENERATE A TIGHT MSLP GRADIENT ACROSS NC... AND EXPECT WINDS TO BE SUSTAINED FROM THE WNW OR NW AT 15-20 MPH (HIGHEST IN THE WEST WHERE SUBSIDENCE WILL BE STRONGEST WITHIN 100-120 M HEIGHT RISES... AND LOWER NE WHERE MIXING HEIGHTS WILL BE LOWER)... WITH GUSTS OF 20-30 MPH... BELOW WIND ADVISORY CRITERIA BUT THIS RISK WILL STILL NEED TO BE WATCHED. THE LOW LEVELS DO DRY OUT WITH DOWNSLOPE FLOW BUT THIS RELATIVELY DRY LAYER WILL BE SHALLOW... AND WE MAY STILL SEE SOME ISOLATED PATCHY LIGHT RAIN OVER THE NRN CWA IN THE MORNING INTO EARLY AFTERNOON. WITH PLENTIFUL CLOUDINESS... BRISK NW WINDS... COLD AIR ADVECTION... AND LOW LEVEL THICKNESSES EXPECTED TO BE AROUND 30 M BELOW NORMAL... EXPECT CHILLY HIGHS FROM THE UPPER 50S TO LOWER 60S... A SLIGHT DOWNWARD BUMP FROM EARLIER FORECAST HIGHS. -GIH && .SHORT TERM /SUNDAY NIGHT THROUGH MONDAY NIGHT/... AS OF 330 AM SATURDAY... AS THE UPPER LOW OVER THE DELMARVA LATE SUNDAY DEPARTS OFF TO THE NORTHEAST...CLOUD COVER ASSOCIATED WITH ITS COMMA HEAD WRAP AROUND MOISTURE WILL DIMINISH BY MIDNIGHT. CLEARING SKIES AND SLOWLY WEAKENING WINDS WILL ALLOW TEMPS TO DIP INTO THE 30S. BASED ON SOME GUIDANCE...ITS POSSIBLE THAT SOME AREAS OVER THE WESTERN PIEDMONT WILL APPROACH FREEZING BY MONDAY MORNING. RIGHT NOW IT APPEARS A LIGHT WIND AND DRYING WILL PREVENT WIDESPREAD FROST. THE SHOT OF COLDER AIR LOOKS TO BE VERY BRIEF AS A SHORTWAVE RIDGE AND SURFACE HIGH PRESSURE BUILD OVER THE REGION...AND BEGIN AN EVOLUTION INTO A PERSISTENT RIDGE OVER THE SOUTHEAST US. WITH A LIGHT NORTHWEST WIND AND NEUTRAL THERMAL ADVECTION...LOW LEVEL THICKNESSES AROUND 1320M MONDAY MORNING SUPPORT MET MOS GUIDANCE MORE SO THAN THE MAV MOS...UPPER 60S NORTHEAST TO AROUND 70 SOUTHWEST. LOWS MONDAY NIGHT 39-44. && .LONG TERM /TUESDAY THROUGH FRIDAY/... AS OF 330 AM SATURDAY... A RIDGE WILL DEVELOP OVER THE SOUTHEAST BY TUESDAY IS IS FORECAST TO PERSIST THROUGH MUCH OF THE WEEK. THE PRIMARY STORM TRACK WILL BE THROUGH THE MIDWEST AND GREAT LAKES REGION...WITH A WEAK FRONT EXPECTED TO MOVE INTO THE MID-ATLANTIC STATES LATE TUESDAY AND THEN WASH OUT WITHOUT HAVING MUCH...IF ANY IMPACT ON CENTRAL NC. MEDIUM RANGE MODELS SHOW THE RIDGE HOLDING STRONG UNTIL LATE IN THE WEEK...WHEN THE RIDGE FINALLY BREAKS DOWN AND A FRONTAL ZONE PUSHES EAST INTO CENTRAL NC FRIDAY/FRIDAY NIGHT. THIS PATTERN SUPPORTS A MUCH WARMER PERIOD FOR CENTRAL NC...WITH THICKNESSES AS MUCH AS 20-30M ABOVE NORMAL AND HIGHS IN THE 70S OR EVEN 80 IN THE SOUTHEAST BY WED/THURS. && .AVIATION /12Z SATURDAY THROUGH WEDNESDAY/... AS OF 730 AM SATURDAY... POOR AVIATION CONDITIONS ARE EXPECTED TO PERSIST THROUGH AT LEAST 06Z TONIGHT. SOME IMPROVEMENT FROM IFR TO MVFR IS EXPECTED AT INT/GSO TOWARD THE END OF THE TAF VALID PERIOD AT 12Z. A DEEP MOIST FLOW FROM THE SOUTH AND SW... AHEAD OF A STRENGTHENING STORM SYSTEM NOW MOVING THROUGH MS AND WRN TN... WILL BRING IFR/LIFR CONDITIONS AND PERIODS OF MOSTLY LIGHT RAIN THROUGH DAYBREAK. WE SHOULD SEE A BRIEF BREAK OR LULL IN THE WIDESPREAD RAIN THROUGH THE LATE MORNING THROUGH EARLY AFTERNOON HOURS... MOST LIKELY FROM 14Z TO 19Z... BUT CIGS ARE LIKELY TO REMAIN IFR WITH MVFR TO IFR VSBYS DURING THIS TIME... WITH IFR/LIFR CONDITIONS MOST LIKELY AT INT/GSO. THEN STARTING SOON AFTER 19Z... A LINE OF SHOWERS AND THUNDERSTORMS IS EXPECTED TO SWEEP EAST-NORTHEAST THROUGH CENTRAL NC THROUGH THE LATE AFTERNOON/EARLY EVENING HOURS... BRINGING THE POTENTIAL FOR LOCALLY STRONG WIND GUSTS OVER 30 MPH... AND PERHAPS A FEW SEVERE STORMS. THESE STORMS ARE EXPECTED TO EXIT THE AREA TO OUR NORTHEAST AFTER 02Z... HOWEVER THE PASSAGE OF A COLD FRONT WITH AN UPPER LEVEL LOW CLOSE ON ITS HEELS WILL BRING A CONTINUED THREAT OF MVFR-IFR CIGS THROUGH LATE EVENING AND INTO EARLY OVERNIGHT. WINDS WILL SHIFT TO BE FROM THE NW WITH THE COLD FRONT PASSAGE... BETWEEN 02Z AND 04Z AT INT/GSO... BETWEEN 04Z AND 06Z AT RDU.... AND BETWEEN 07Z AND 09Z AT RWI/FAY. LOOKING BEYOND 12Z TONIGHT... MVFR CIGS ARE EXPECTED TO DOMINATE THROUGH 18Z SUN. WINDS WILL BE BRISK AND GUSTY FROM THE NW THROUGHOUT SUNDAY... BRINGING A CROSSWIND THREAT MAINLY AT GSO/RDU. BETWEEN 18Z SUN AND 00Z MON... SLOW WEST-TO-EAST CLEARING IS EXPECTED AS THE UPPER LEVEL LOW MOVES SLOWLY THROUGH THE AREA... WITH AT TREND TO VFR AT INT/GSO/RDU LIKELY BY 00Z... AND AT RWI/FAY BETWEEN 00Z AND 06Z EARLY MON MORNING. VFR CONDITIONS ARE LIKELY FROM LATE SUN NIGHT THROUGH WED AS HIGH PRESSURE BUILDS INTO THE AREA FROM THE WEST. -GIH && .RAH WATCHES/WARNINGS/ADVISORIES... DENSE FOG ADVISORY UNTIL 10 AM EDT THIS MORNING FOR NCZ007>009- 021>025-038>040-073-074-083. && $$ SYNOPSIS...HARTFIELD NEAR TERM...HARTFIELD SHORT TERM...SMITH LONG TERM...SMITH AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS RALEIGH NC
330 AM EDT SAT MAR 29 2014 .SYNOPSIS...A STRONG STORM SYSTEM WILL TRACK EASTWARD THROUGH THE REGION TODAY THROUGH SUNDAY. HIGH PRESSURE WILL BUILD INTO THE AREA SUNDAY NIGHT THROUGH TUESDAY. && .NEAR TERM /TODAY THROUGH SUNDAY/... AS OF 300 AM SATURDAY... FOR TODAY/TONIGHT: LATEST OBSERVATIONAL DATA AND SHORT-TERM MODEL GUIDANCE GENERALLY SUPPORT OUR EARLIER THINKING... THAT WE`LL SEE A BORDERLINE STRONG/SEVERE EVENT WITH DAMAGING WIND AS A PRIME THREAT... AND WITH EXTENT/SEVERITY LIKELY LIMITED BY MARGINAL INSTABILITY AND A DELAY IN THE MORE VIGOROUS DYNAMICS. CURRENTLY... WIDESPREAD RAIN PERSISTS OVER MUCH OF CENTRAL/ERN NC... DRIVEN BY DEEP MOIST UPGLIDE AND LOW LEVEL MASS CONVERGENCE ASSOCIATED WITH A WEAK WAVE PASSING NORTHEAST THROUGH THE AREA... IN THE WARM SECTOR AHEAD OF THE DEEPENING UPPER LOW DIGGING TOWARD THE MID MISS VALLEY. LATEST MODEL RUNS SUGGEST THAT THIS MOIST UPGLIDE WILL PERSIST FOR SEVERAL MORE HOURS BEFORE THE FOCUS SHIFTS TO OUR NORTHEAST... BRINGING A RELATIVE LULL IN COVERAGE (MORE PATCHY THAN THE CURRENT WIDESPREAD COVERAGE) FOR MOST AREAS BY MID MORNING AS OVERALL ASCENT WEAKENS BRIEFLY. THIS SCENARIO IS SUPPORTED BY THE MOST RECENT HRRR RUNS. WILL INDICATE PRECIP CHANCES SLIPPING BACK TO LIKELY WITH A PERIOD OF LOWER QPF FROM SOON AFTER SUNRISE THROUGH MUCH OF THE MORNING... BUT EXPECT THICK LOW-BASED CLOUDS TO PERSIST AREAWIDE. THE LATEST SURFACE ANALYSIS SHOWS SLIGHTLY MORE STABLE AIR OVER THE NW CWA (AND EXTENDING BACK TO THE EASTERN SLOPES OF WRN NC) WHERE THE RAIN IS EXITING... AND THESE AREAS WILL BE SUSCEPTIBLE TO DENSE FOG THROUGH DAYBREAK GIVEN THE LIGHT/CALM WINDS... DAMP GROUND... AND PROXIMITY TO HIGHER TERRAIN TO HELP BLOCK THIS GROWING STABLE POOL. WILL ISSUE A DENSE FOG ADVISORY THIS MORNING FOR THE NW CWA... WHERE 1/4 MI VSBYS ARE QUICKLY BECOMING PERVASIVE. ATTENTION THEN TURNS TO THE MATURE MCS NOW TRACKING THROUGH MS INTO WRN AL (WITH IMPRESSIVE SATELLITE AND RADAR SIGNATURES). ACCORDING TO EXTRAPOLATION AND RECENT RAP/HRRR RUNS... THE MCV EMANATING FROM THIS MCS IS ON PACE TO TRACK NORTHEASTWARD... PASSING THROUGH CENTRAL/ERN NC BETWEEN 18Z AND 23Z TODAY. A FEW FACTORS ARE APPARENT WHICH SHOULD ENHANCE INSTABILITY OVER CENTRAL NC THIS AFTERNOON... INCLUDING SIMPLY THE EXISTENCE OF THE MCV AND ITS SIGNAL ON HIGH-RES MODEL OUTPUT... AN AREA OF RELATIVE DRYING ALOFT (NOTED AT 700 MB ON THE NAM/GFS) TO POTENTIALLY ELEVATE INSTABILITY... WARM NEAR-SURFACE AIR WITH HIGH DEW POINTS (UPPER 50S-LOWER 60S)... AND A ROUGHLY 40 KT SOUTHWESTERLY LOW LEVEL JET EXPECTED TO SWEEP NORTHEAST ACROSS THE ERN HALF OF NC 18Z-00Z TODAY. MODELS STILL INDICATE FAIRLY SKINNY MUCAPE UP TO 500-1000 J/KG MAINLY OVER THE SE CWA FROM 18Z- 03Z (PEAKING 21Z-00Z) WITH LONG STRAIGHT HODOGRAPHS... SUGGESTING A MAINLY WIND THREAT GIVEN SOME DRYING ALOFT. INITIALLY THOUGH -- AND ESPECIALLY IN THE TRIAD -- THESE HODOGRAPHS ARE CURVED ENOUGH TO BRING ABOUT A CONCERN FOR AN ISOLATED TORNADO IF WE CAN GET ENOUGH INSTABILITY DURING THE EARLY AFTERNOON... WITH THE PRIMARY THREAT ALONG THE EDGE OF THE WEAK STABLE POOL. BUT IF THIS PRECEDING RAIN PERSISTS LONG ENOUGH INTO THE DAY... IT COULD LIMIT THIS INSTABILITY. ANOTHER MITIGATING FACTOR IS THE APPARENT SLIGHT TEMPORAL DISCONNECT BETWEEN THESE FAVORABLE SIGNALS AND THE BEST DYNAMIC FORCING FOR ASCENT... WHICH IS EXPECTED TO ARRIVE THIS EVENING/TONIGHT IN THE FORM OF STRONG DPVA AND 150-200 M HEIGHT FALLS... AS WELL AS A 500 MB JET STREAK OF 60+ KTS WHICH STRENGTHENS ON THE SOUTH SIDE OF THE LOW AND NOSES INTO CENTRAL/ERN NC 00Z-06Z. FINALLY... THE LATEST HRRR RUNS SUGGEST THAT THE COLD POOL NOW TRACKING THROUGH AL MAY TRACK MOSTLY ACROSS GA/SC... AND THAT CONVECTIVE DEVELOPMENT OVER NC MAY BE SUBDUED. IN SUMMARY... WHILE THE THREAT OF SEVERE WINDS (AND POSSIBLY AN ISOLATED WEAK TORNADO OR SMALL HAIL REPORT OR TWO) REMAINS OVER OUR SOUTHEAST... A WIDESPREAD SEVERE WEATHER EVENT IS NOT ANTICIPATED. WE MAY SEE ANOTHER NARROW BAND OF MOSTLY SHOWERS THIS EVENING AS THE ACTUAL COLD FRONT SWEEPS EASTWARD... FOLLOWED BY A SW TO NE END TO POPS OVERNIGHT. STILL EXPECT A CYCLOGENESIS PATTERN CLOSE TO A MILLER-B... WITH THE PRIMARY SURFACE LOW DISSIPATING OVER FAR SW VA AS SECONDARY LOW PRESSURE FORMS ALONG A WEAK TRIPLE POINT OVER THE SW NC FOOTHILLS AND THEN TRACKS NE OVER WRN AND NORTH CENTRAL NC INTO SE VA TONIGHT. THE RAPID STRENGTHENING OF THE UPPER LOW AS IT TRACKS OVERHEAD WILL LEAD TO RAPID DEEPENING OF THE SURFACE LOW AND THUS AN INCREASE IN WINDS BEHIND THE COLD FRONT LATE TONIGHT. DESPITE THE LOW LEVEL STABILIZATION... FORECAST SOUNDINGS SUGGEST PLENTY OF LINGERING MOISTURE IN THE 925-700 MB LAYER FOR LINGERING MOSTLY CLOUDY SKIES ESPECIALLY IN THE NORTHERN CWA OVERNIGHT. FOLLOWING HIGH-RES SHORT TERM GUIDANCE... EXPECT HIGHS TODAY FROM MID 60S NW TO MID 70S SE... NO BETTER THAN A 10-15 DEG F DIURNAL RANGE. LOWS TONIGHT 41 NW TO 48 SE. FOR SUNDAY: EXPECT MOSTLY CLOUDY SKIES TO HOLD PARTICULARLY OVER THE NRN CWA AS THE LOW ALOFT SHIFTS OVER THE REGION. THE DEEPENING SURFACE LOW JUST TO OUR NE WILL GENERATE A TIGHT MSLP GRADIENT ACROSS NC... AND EXPECT WINDS TO BE SUSTAINED FROM THE WNW OR NW AT 15-20 MPH (HIGHEST IN THE WEST WHERE SUBSIDENCE WILL BE STRONGEST WITHIN 100-120 M HEIGHT RISES... AND LOWER NE WHERE MIXING HEIGHTS WILL BE LOWER)... WITH GUSTS OF 20-30 MPH... BELOW WIND ADVISORY CRITERIA BUT THIS RISK WILL STILL NEED TO BE WATCHED. THE LOW LEVELS DO DRY OUT WITH DOWNSLOPE FLOW BUT THIS RELATIVELY DRY LAYER WILL BE SHALLOW... AND WE MAY STILL SEE SOME ISOLATED PATCHY LIGHT RAIN OVER THE NRN CWA IN THE MORNING INTO EARLY AFTERNOON. WITH PLENTIFUL CLOUDINESS... BRISK NW WINDS... COLD AIR ADVECTION... AND LOW LEVEL THICKNESSES EXPECTED TO BE AROUND 30 M BELOW NORMAL... EXPECT CHILLY HIGHS FROM THE UPPER 50S TO LOWER 60S... A SLIGHT DOWNWARD BUMP FROM EARLIER FORECAST HIGHS. -GIH && .SHORT TERM /SUNDAY NIGHT THROUGH MONDAY NIGHT/... AS OF 330 AM SATURDAY... AS THE UPPER LOW OVER THE DELMARVA LATE SUNDAY DEPARTS OFF TO THE NORTHEAST...CLOUD COVER ASSOCIATED WITH ITS COMMA HEAD WRAP AROUND MOISTURE WILL DIMINISH BY MIDNIGHT. CLEARING SKIES AND SLOWLY WEAKENING WINDS WILL ALLOW TEMPS TO DIP INTO THE 30S. BASED ON SOME GUIDANCE...ITS POSSIBLE THAT SOME AREAS OVER THE WESTERN PIEDMONT WILL APPROACH FREEZING BY MONDAY MORNING. RIGHT NOW IT APPEARS A LIGHT WIND AND DRYING WILL PREVENT WIDESPREAD FROST. THE SHOT OF COLDER AIR LOOKS TO BE VERY BRIEF AS A SHORTWAVE RIDGE AND SURFACE HIGH PRESSURE BUILD OVER THE REGION...AND BEGIN AN EVOLUTION INTO A PERSISTENT RIDGE OVER THE SOUTHEAST US. WITH A LIGHT NORTHWEST WIND AND NEUTRAL THERMAL ADVECTION...LOW LEVEL THICKNESSES AROUND 1320M MONDAY MORNING SUPPORT MET MOS GUIDANCE MORE SO THAN THE MAV MOS...UPPER 60S NORTHEAST TO AROUND 70 SOUTHWEST. LOWS MONDAY NIGHT 39-44. && .LONG TERM /TUESDAY THROUGH FRIDAY/... AS OF 330 AM SATURDAY... A RIDGE WILL DEVELOP OVER THE SOUTHEAST BY TUESDAY IS IS FORECAST TO PERSIST THROUGH MUCH OF THE WEEK. THE PRIMARY STORM TRACK WILL BE THROUGH THE MIDWEST AND GREAT LAKES REGION...WITH A WEAK FRONT EXPECTED TO MOVE INTO THE MID-ATLANTIC STATES LATE TUESDAY AND THEN WASH OUT WITHOUT HAVING MUCH...IF ANY IMPACT ON CENTRAL NC. MEDIUM RANGE MODELS SHOW THE RIDGE HOLDING STRONG UNTIL LATE IN THE WEEK...WHEN THE RIDGE FINALLY BREAKS DOWN AND A FRONTAL ZONE PUSHES EAST INTO CENTRAL NC FRIDAY/FRIDAY NIGHT. THIS PATTERN SUPPORTS A MUCH WARMER PERIOD FOR CENTRAL NC...WITH THICKNESSES AS MUCH AS 20-30M ABOVE NORMAL AND HIGHS IN THE 70S OR EVEN 80 IN THE SOUTHEAST BY WED/THURS. && .AVIATION /06Z SATURDAY THROUGH WEDNESDAY/... AS OF 100 AM SATURDAY... POOR AVIATION CONDITIONS ARE EXPECTED TO PERSIST THROUGH AT LEAST 00Z TONIGHT... AND POTENTIALLY THROUGH THE END OF THE TAF VALID PERIOD AT 06Z. A DEEP MOIST FLOW FROM THE SOUTH AND SW... AHEAD OF A STRENGTHENING STORM SYSTEM NOW MOVING THROUGH MS AND WRN TN... WILL BRING IFR/LIFR CONDITIONS AND PERIODS OF MOSTLY LIGHT RAIN THROUGH DAYBREAK. WE SHOULD SEE A BRIEF BREAK OR LULL IN THE WIDESPREAD RAIN THROUGH MUCH OF THE MORNING HOURS... MOST LIKELY FROM 11Z TO 16Z... BUT CIGS ARE LIKELY TO REMAIN IFR WITH MVFR TO IFR VSBYS DURING THIS TIME. THEN STARTING SOON AFTER 16Z... A LINE OF SHOWERS AND THUNDERSTORMS IS EXPECTED TO SWEEP EAST-NORTHEAST THROUGH CENTRAL NC THROUGH THE AFTERNOON HOURS... BRINGING THE POTENTIAL FOR LOCALLY STRONG WIND GUSTS OVER 30 MPH... AND PERHAPS A FEW SEVERE STORMS. THESE STORMS ARE EXPECTED TO EXIT THE AREA TO OUR NORTHEAST AFTER 22Z... HOWEVER THE PASSAGE OF A COLD FRONT WITH AN UPPER LEVEL LOW CLOSE ON ITS HEELS WILL BRING A CONTINUED THREAT OF MVFR-IFR CIGS THROUGH THIS EVENING. WINDS WILL SHIFT TO BE FROM THE NW WITH THE COLD FRONT PASSAGE... BETWEEN 02Z AND 04Z AT INT/GSO AND BETWEEN 04Z AND 06Z AT RDU. LOOKING BEYOND 06Z TONIGHT... MVFR CIGS ARE EXPECTED TO DOMINATE THROUGH 18Z SUN. WINDS WILL BE BRISK AND GUSTY FROM THE NW THROUGHOUT SUNDAY... BRINGING A CROSSWIND THREAT MAINLY AT GSO/RDU. BETWEEN 18Z SUN AND 00Z MON... SLOW WEST-TO-EAST CLEARING IS EXPECTED AS THE UPPER LEVEL LOW MOVES SLOWLY THROUGH THE AREA... WITH AT TREND TO VFR AT INT/GSO/RDU LIKELY BY 00Z... AND AT RWI/FAY BETWEEN 00Z AND 06Z EARLY MON MORNING. VFR CONDITIONS ARE LIKELY FROM LATE SUN NIGHT THROUGH WED AS HIGH PRESSURE BUILDS INTO THE AREA FROM THE WEST. -GIH && .RAH WATCHES/WARNINGS/ADVISORIES... DENSE FOG ADVISORY UNTIL 10 AM EDT THIS MORNING FOR NCZ007>009- 021>025-038>040-073-074-083. && $$ SYNOPSIS...HARTFIELD NEAR TERM...HARTFIELD SHORT TERM...SMITH LONG TERM...SMITH AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS RALEIGH NC
325 AM EDT SAT MAR 29 2014 .SYNOPSIS...A STRONG STORM SYSTEM WILL TRACK EASTWARD THROUGH THE REGION TODAY THROUGH SUNDAY. HIGH PRESSURE WILL BUILD INTO THE AREA SUNDAY NIGHT THROUGH TUESDAY. && .NEAR TERM /TODAY THROUGH SUNDAY/... AS OF 300 AM SATURDAY... FOR TODAY/TONIGHT: LATEST OBSERVATIONAL DATA AND SHORT-TERM MODEL GUIDANCE GENERALLY SUPPORT OUR EARLIER THINKING... THAT WE`LL SEE A BORDERLINE STRONG/SEVERE EVENT WITH DAMAGING WIND AS A PRIME THREAT... AND WITH EXTENT/SEVERITY LIKELY LIMITED BY MARGINAL INSTABILITY AND A DELAY IN THE MORE VIGOROUS DYNAMICS. CURRENTLY... WIDESPREAD RAIN PERSISTS OVER MUCH OF CENTRAL/ERN NC... DRIVEN BY DEEP MOIST UPGLIDE AND LOW LEVEL MASS CONVERGENCE ASSOCIATED WITH A WEAK WAVE PASSING NORTHEAST THROUGH THE AREA... IN THE WARM SECTOR AHEAD OF THE DEEPENING UPPER LOW DIGGING TOWARD THE MID MISS VALLEY. LATEST MODEL RUNS SUGGEST THAT THIS MOIST UPGLIDE WILL PERSIST FOR SEVERAL MORE HOURS BEFORE THE FOCUS SHIFTS TO OUR NORTHEAST... BRINGING A RELATIVE LULL IN COVERAGE (MORE PATCHY THAN THE CURRENT WIDESPREAD COVERAGE) FOR MOST AREAS BY MID MORNING AS OVERALL ASCENT WEAKENS BRIEFLY. THIS SCENARIO IS SUPPORTED BY THE MOST RECENT HRRR RUNS. WILL INDICATE PRECIP CHANCES SLIPPING BACK TO LIKELY WITH A PERIOD OF LOWER QPF FROM SOON AFTER SUNRISE THROUGH MUCH OF THE MORNING... BUT EXPECT THICK LOW-BASED CLOUDS TO PERSIST AREAWIDE. THE LATEST SURFACE ANALYSIS SHOWS SLIGHTLY MORE STABLE AIR OVER THE NW CWA (AND EXTENDING BACK TO THE EASTERN SLOPES OF WRN NC) WHERE THE RAIN IS EXITING... AND THESE AREAS WILL BE SUSCEPTIBLE TO DENSE FOG THROUGH DAYBREAK GIVEN THE LIGHT/CALM WINDS... DAMP GROUND... AND PROXIMITY TO HIGHER TERRAIN TO HELP BLOCK THIS GROWING STABLE POOL. WILL ISSUE A DENSE FOG ADVISORY THIS MORNING FOR THE NW CWA... WHERE 1/4 MI VSBYS ARE QUICKLY BECOMING PERVASIVE. ATTENTION THEN TURNS TO THE MATURE MCS NOW TRACKING THROUGH MS INTO WRN AL (WITH IMPRESSIVE SATELLITE AND RADAR SIGNATURES). ACCORDING TO EXTRAPOLATION AND RECENT RAP/HRRR RUNS... THE MCV EMANATING FROM THIS MCS IS ON PACE TO TRACK NORTHEASTWARD... PASSING THROUGH CENTRAL/ERN NC BETWEEN 18Z AND 23Z TODAY. A FEW FACTORS ARE APPARENT WHICH SHOULD ENHANCE INSTABILITY OVER CENTRAL NC THIS AFTERNOON... INCLUDING SIMPLY THE EXISTENCE OF THE MCV AND ITS SIGNAL ON HIGH-RES MODEL OUTPUT... AN AREA OF RELATIVE DRYING ALOFT (NOTED AT 700 MB ON THE NAM/GFS) TO POTENTIALLY ELEVATE INSTABILITY... WARM NEAR-SURFACE AIR WITH HIGH DEW POINTS (UPPER 50S-LOWER 60S)... AND A ROUGHLY 40 KT SOUTHWESTERLY LOW LEVEL JET EXPECTED TO SWEEP NORTHEAST ACROSS THE ERN HALF OF NC 18Z-00Z TODAY. MODELS STILL INDICATE FAIRLY SKINNY MUCAPE UP TO 500-1000 J/KG MAINLY OVER THE SE CWA FROM 18Z- 03Z (PEAKING 21Z-00Z) WITH LONG STRAIGHT HODOGRAPHS... SUGGESTING A MAINLY WIND THREAT GIVEN SOME DRYING ALOFT. INITIALLY THOUGH -- AND ESPECIALLY IN THE TRIAD -- THESE HODOGRAPHS ARE CURVED ENOUGH TO BRING ABOUT A CONCERN FOR AN ISOLATED TORNADO IF WE CAN GET ENOUGH INSTABILITY DURING THE EARLY AFTERNOON... WITH THE PRIMARY THREAT ALONG THE EDGE OF THE WEAK STABLE POOL. BUT IF THIS PRECEDING RAIN PERSISTS LONG ENOUGH INTO THE DAY... IT COULD LIMIT THIS INSTABILITY. ANOTHER MITIGATING FACTOR IS THE APPARENT SLIGHT TEMPORAL DISCONNECT BETWEEN THESE FAVORABLE SIGNALS AND THE BEST DYNAMIC FORCING FOR ASCENT... WHICH IS EXPECTED TO ARRIVE THIS EVENING/TONIGHT IN THE FORM OF STRONG DPVA AND 150-200 M HEIGHT FALLS... AS WELL AS A 500 MB JET STREAK OF 60+ KTS WHICH STRENGTHENS ON THE SOUTH SIDE OF THE LOW AND NOSES INTO CENTRAL/ERN NC 00Z-06Z. FINALLY... THE LATEST HRRR RUNS SUGGEST THAT THE COLD POOL NOW TRACKING THROUGH AL MAY TRACK MOSTLY ACROSS GA/SC... AND THAT CONVECTIVE DEVELOPMENT OVER NC MAY BE SUBDUED. IN SUMMARY... WHILE THE THREAT OF SEVERE WINDS (AND POSSIBLY AN ISOLATED WEAK TORNADO OR SMALL HAIL REPORT OR TWO) REMAINS OVER OUR SOUTHEAST... A WIDESPREAD SEVERE WEATHER EVENT IS NOT ANTICIPATED. WE MAY SEE ANOTHER NARROW BAND OF MOSTLY SHOWERS THIS EVENING AS THE ACTUAL COLD FRONT SWEEPS EASTWARD... FOLLOWED BY A SW TO NE END TO POPS OVERNIGHT. STILL EXPECT A CYCLOGENESIS PATTERN CLOSE TO A MILLER-B... WITH THE PRIMARY SURFACE LOW DISSIPATING OVER FAR SW VA AS SECONDARY LOW PRESSURE FORMS ALONG A WEAK TRIPLE POINT OVER THE SW NC FOOTHILLS AND THEN TRACKS NE OVER WRN AND NORTH CENTRAL NC INTO SE VA TONIGHT. THE RAPID STRENGTHENING OF THE UPPER LOW AS IT TRACKS OVERHEAD WILL LEAD TO RAPID DEEPENING OF THE SURFACE LOW AND THUS AN INCREASE IN WINDS BEHIND THE COLD FRONT LATE TONIGHT. DESPITE THE LOW LEVEL STABILIZATION... FORECAST SOUNDINGS SUGGEST PLENTY OF LINGERING MOISTURE IN THE 925-700 MB LAYER FOR LINGERING MOSTLY CLOUDY SKIES ESPECIALLY IN THE NORTHERN CWA OVERNIGHT. FOLLOWING HIGH-RES SHORT TERM GUIDANCE... EXPECT HIGHS TODAY FROM MID 60S NW TO MID 70S SE... NO BETTER THAN A 10-15 DEG F DIURNAL RANGE. LOWS TONIGHT 41 NW TO 48 SE. FOR SUNDAY: EXPECT MOSTLY CLOUDY SKIES TO HOLD PARTICULARLY OVER THE NRN CWA AS THE LOW ALOFT SHIFTS OVER THE REGION. THE DEEPENING SURFACE LOW JUST TO OUR NE WILL GENERATE A TIGHT MSLP GRADIENT ACROSS NC... AND EXPECT WINDS TO BE SUSTAINED FROM THE WNW OR NW AT 15-20 MPH (HIGHEST IN THE WEST WHERE SUBSIDENCE WILL BE STRONGEST WITHIN 100-120 M HEIGHT RISES... AND LOWER NE WHERE MIXING HEIGHTS WILL BE LOWER)... WITH GUSTS OF 20-30 MPH... BELOW WIND ADVISORY CRITERIA BUT THIS RISK WILL STILL NEED TO BE WATCHED. THE LOW LEVELS DO DRY OUT WITH DOWNSLOPE FLOW BUT THIS RELATIVELY DRY LAYER WILL BE SHALLOW... AND WE MAY STILL SEE SOME ISOLATED PATCHY LIGHT RAIN OVER THE NRN CWA IN THE MORNING INTO EARLY AFTERNOON. WITH PLENTIFUL CLOUDINESS... BRISK NW WINDS... COLD AIR ADVECTION... AND LOW LEVEL THICKNESSES EXPECTED TO BE AROUND 30 M BELOW NORMAL... EXPECT CHILLY HIGHS FROM THE UPPER 50S TO LOWER 60S... A SLIGHT DOWNWARD BUMP FROM EARLIER FORECAST HIGHS. -GIH && .SHORT TERM / /... AS OF 330 PM FRIDAY... TO BE UPDATED. && .LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/... AS OF 145 PM FRIDAY... SUNDAY NIGHT AND MONDAY WILL BRING CLEAR/SUNNY/MILD WEATHER AS HIGH PRESSURE (OF PACIFIC ORIGIN) MOVES OVERHEAD. LOWS 35-42. HIGHS 67- 72. TUESDAY THROUGH THURSDAY NIGHT... MID AND UPPER LEVEL RIDGING WILL LEAD TO A MUCH WARMER PERIOD FOR CONSECUTIVE DAYS. THE MAIN STORM TRACK FROM THE PLAINS TO THE GREAT LAKES INTO SE CANADA WILL BE FAR ENOUGH AWAY TO KEEP ANY POP OUT OF THE FORECAST. THE TEMPERATURES SHOULD WARM WELL INTO THE 70S (WITH LOWER 80S POSSIBLE IN THE SANDHILLS MID-WEEK) WITH THE LOW LEVEL SW FLOW. LOWS WARM FROM 40-45 TUE... INTO THE LOWER TO MID 50S THU. THE NEXT SIGNIFICANT WEATHER MAKER SHOULD HOLD OFF UNTIL THURSDAY NIGHT AND/OR FRIDAY ASSOCIATED WITH STORM TRACK FROM THE SOUTHERN PLAINS TO THE OHIO VALLEY... AND A TRAILING COLD FRONT THE SHOULD EDGE TO NEAR THE APPALACHIANS BY 12Z/FRIDAY... AND PUSH EAST ACROSS THE REGION FRIDAY. WE WILL PLACE A LOW END CHANCE POP IN THE FORECAST THU NIGHT AND FRIDAY WITH INCREASING CLOUDINESS. LOWS 55- 62. HIGHS FRIDAY GENERALLY 70-75 DEPENDING ON TIMING OF THE FRONT AND ASSOCIATED SHOWER CHANCES. && .AVIATION /06Z SATURDAY THROUGH WEDNESDAY/... AS OF 100 AM SATURDAY... POOR AVIATION CONDITIONS ARE EXPECTED TO PERSIST THROUGH AT LEAST 00Z TONIGHT... AND POTENTIALLY THROUGH THE END OF THE TAF VALID PERIOD AT 06Z. A DEEP MOIST FLOW FROM THE SOUTH AND SW... AHEAD OF A STRENGTHENING STORM SYSTEM NOW MOVING THROUGH MS AND WRN TN... WILL BRING IFR/LIFR CONDITIONS AND PERIODS OF MOSTLY LIGHT RAIN THROUGH DAYBREAK. WE SHOULD SEE A BRIEF BREAK OR LULL IN THE WIDESPREAD RAIN THROUGH MUCH OF THE MORNING HOURS... MOST LIKELY FROM 11Z TO 16Z... BUT CIGS ARE LIKELY TO REMAIN IFR WITH MVFR TO IFR VSBYS DURING THIS TIME. THEN STARTING SOON AFTER 16Z... A LINE OF SHOWERS AND THUNDERSTORMS IS EXPECTED TO SWEEP EAST-NORTHEAST THROUGH CENTRAL NC THROUGH THE AFTERNOON HOURS... BRINGING THE POTENTIAL FOR LOCALLY STRONG WIND GUSTS OVER 30 MPH... AND PERHAPS A FEW SEVERE STORMS. THESE STORMS ARE EXPECTED TO EXIT THE AREA TO OUR NORTHEAST AFTER 22Z... HOWEVER THE PASSAGE OF A COLD FRONT WITH AN UPPER LEVEL LOW CLOSE ON ITS HEELS WILL BRING A CONTINUED THREAT OF MVFR-IFR CIGS THROUGH THIS EVENING. WINDS WILL SHIFT TO BE FROM THE NW WITH THE COLD FRONT PASSAGE... BETWEEN 02Z AND 04Z AT INT/GSO AND BETWEEN 04Z AND 06Z AT RDU. LOOKING BEYOND 06Z TONIGHT... MVFR CIGS ARE EXPECTED TO DOMINATE THROUGH 18Z SUN. WINDS WILL BE BRISK AND GUSTY FROM THE NW THROUGHOUT SUNDAY... BRINGING A CROSSWIND THREAT MAINLY AT GSO/RDU. BETWEEN 18Z SUN AND 00Z MON... SLOW WEST-TO-EAST CLEARING IS EXPECTED AS THE UPPER LEVEL LOW MOVES SLOWLY THROUGH THE AREA... WITH AT TREND TO VFR AT INT/GSO/RDU LIKELY BY 00Z... AND AT RWI/FAY BETWEEN 00Z AND 06Z EARLY MON MORNING. VFR CONDITIONS ARE LIKELY FROM LATE SUN NIGHT THROUGH WED AS HIGH PRESSURE BUILDS INTO THE AREA FROM THE WEST. -GIH && .RAH WATCHES/WARNINGS/ADVISORIES... DENSE FOG ADVISORY UNTIL 10 AM EDT THIS MORNING FOR NCZ007>009- 021>025-038>040-073-074-083. && $$ SYNOPSIS...HARTFIELD NEAR TERM...HARTFIELD SHORT TERM... LONG TERM...BADGETT AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS RALEIGH NC
305 AM EDT SAT MAR 29 2014 .SYNOPSIS...A STRONG STORM SYSTEM WILL TRACK EASTWARD THROUGH THE REGION TODAY THROUGH SUNDAY. HIGH PRESSURE WILL BUILD INTO THE AREA SUNDAY NIGHT THROUGH TUESDAY. && .NEAR TERM /TODAY THROUGH SUNDAY/... AS OF 300 AM SATURDAY... FOR TODAY/TONIGHT: LATEST OBSERVATIONAL DATA AND SHORT-TERM MODEL GUIDANCE GENERALLY SUPPORT OUR EARLIER THINKING... THAT WE`LL SEE A BORDERLINE STRONG/SEVERE EVENT WITH DAMAGING WIND AS A PRIME THREAT... AND WITH EXTENT/SEVERITY LIKELY LIMITED BY MARGINAL INSTABILITY AND A DELAY IN THE MORE VIGOROUS DYNAMICS. CURRENTLY... WIDESPREAD RAIN PERSISTS OVER MUCH OF CENTRAL/ERN NC... DRIVEN BY DEEP MOIST UPGLIDE AND LOW LEVEL MASS CONVERGENCE ASSOCIATED WITH A WEAK WAVE PASSING NORTHEAST THROUGH THE AREA... IN THE WARM SECTOR AHEAD OF THE DEEPENING UPPER LOW DIGGING TOWARD THE MID MISS VALLEY. LATEST MODEL RUNS SUGGEST THAT THIS MOIST UPGLIDE WILL PERSIST FOR SEVERAL MORE HOURS BEFORE THE FOCUS SHIFTS TO OUR NORTHEAST... BRINGING A RELATIVE LULL IN COVERAGE (MORE PATCHY THAN THE CURRENT WIDESPREAD COVERAGE) FOR MOST AREAS BY MID MORNING AS OVERALL ASCENT WEAKENS BRIEFLY. THIS SCENARIO IS SUPPORTED BY THE MOST RECENT HRRR RUNS. WILL INDICATE PRECIP CHANCES SLIPPING BACK TO LIKELY WITH A PERIOD OF LOWER QPF FROM SOON AFTER SUNRISE THROUGH MUCH OF THE MORNING... BUT EXPECT THICK LOW-BASED CLOUDS TO PERSIST AREAWIDE. THE LATEST SURFACE ANALYSIS SHOWS SLIGHTLY MORE STABLE AIR OVER THE NW CWA (AND EXTENDING BACK TO THE EASTERN SLOPES OF WRN NC) WHERE THE RAIN IS EXITING... AND THESE AREAS WILL BE SUSCEPTIBLE TO DENSE FOG THROUGH DAYBREAK GIVEN THE LIGHT/CALM WINDS... DAMP GROUND... AND PROXIMITY TO HIGHER TERRAIN TO HELP BLOCK THIS GROWING STABLE POOL. WILL ISSUE A DENSE FOG ADVISORY THIS MORNING FOR THE NW CWA... WHERE 1/4 MI VSBYS ARE QUICKLY BECOMING PERVASIVE. ATTENTION THEN TURNS TO THE MATURE MCS NOW TRACKING THROUGH MS INTO WRN AL (WITH IMPRESSIVE SATELLITE AND RADAR SIGNATURES). ACCORDING TO EXTRAPOLATION AND RECENT RAP/HRRR RUNS... THE MCV EMANATING FROM THIS MCS IS ON PACE TO TRACK NORTHEASTWARD... PASSING THROUGH CENTRAL/ERN NC BETWEEN 18Z AND 23Z TODAY. A FEW FACTORS ARE APPARENT WHICH SHOULD ENHANCE INSTABILITY OVER CENTRAL NC THIS AFTERNOON... INCLUDING SIMPLY THE EXISTENCE OF THE MCV AND ITS SIGNAL ON HIGH-RES MODEL OUTPUT... AN AREA OF RELATIVE DRYING ALOFT (NOTED AT 700 MB ON THE NAM/GFS) TO POTENTIALLY ELEVATE INSTABILITY... WARM NEAR-SURFACE AIR WITH HIGH DEW POINTS (UPPER 50S-LOWER 60S)... AND A ROUGHLY 40 KT SOUTHWESTERLY LOW LEVEL JET EXPECTED TO SWEEP NORTHEAST ACROSS THE ERN HALF OF NC 18Z-00Z TODAY. MODELS STILL INDICATE FAIRLY SKINNY MUCAPE UP TO 500-1000 J/KG MAINLY OVER THE SE CWA FROM 18Z- 03Z (PEAKING 21Z-00Z) WITH LONG STRAIGHT HODOGRAPHS... SUGGESTING A MAINLY WIND THREAT GIVEN SOME DRYING ALOFT. INITIALLY THOUGH -- AND ESPECIALLY IN THE TRIAD -- THESE HODOGRAPHS ARE CURVED ENOUGH TO BRING ABOUT A CONCERN FOR AN ISOLATED TORNADO IF WE CAN GET ENOUGH INSTABILITY DURING THE EARLY AFTERNOON... WITH THE PRIMARY THREAT ALONG THE EDGE OF THE WEAK STABLE POOL. BUT IF THIS PRECEDING RAIN PERSISTS LONG ENOUGH INTO THE DAY... IT COULD LIMIT THIS INSTABILITY. ANOTHER MITIGATING FACTOR IS THE APPARENT SLIGHT TEMPORAL DISCONNECT BETWEEN THESE FAVORABLE SIGNALS AND THE BEST DYNAMIC FORCING FOR ASCENT... WHICH IS EXPECTED TO ARRIVE THIS EVENING/TONIGHT IN THE FORM OF STRONG DPVA AND 150-200 M HEIGHT FALLS... AS WELL AS A 500 MB JET STREAK OF 60+ KTS WHICH STRENGTHENS ON THE SOUTH SIDE OF THE LOW AND NOSES INTO CENTRAL/ERN NC 00Z-06Z. FINALLY... THE LATEST HRRR RUNS SUGGEST THAT THE COLD POOL NOW TRACKING THROUGH AL MAY TRACK MOSTLY ACROSS GA/SC... AND THAT CONVECTIVE DEVELOPMENT OVER NC MAY BE SUBDUED. IN SUMMARY... WHILE THE THREAT OF SEVERE WINDS (AND POSSIBLY AN ISOLATED WEAK TORNADO OR SMALL HAIL REPORT OR TWO) REMAINS OVER OUR SOUTHEAST... A WIDESPREAD SEVERE WEATHER EVENT IS NOT ANTICIPATED. WE MAY SEE ANOTHER NARROW BAND OF MOSTLY SHOWERS THIS EVENING AS THE ACTUAL COLD FRONT SWEEPS EASTWARD... FOLLOWED BY A SW TO NE END TO POPS OVERNIGHT. STILL EXPECT A CYCLOGENESIS PATTERN CLOSE TO A MILLER-B... WITH THE PRIMARY SURFACE LOW DISSIPATING OVER FAR SW VA AS SECONDARY LOW PRESSURE FORMS ALONG A WEAK TRIPLE POINT OVER THE SW NC FOOTHILLS AND THEN TRACKS NE OVER WRN AND NORTH CENTRAL NC INTO SE VA TONIGHT. THE RAPID STRENGTHENING OF THE UPPER LOW AS IT TRACKS OVERHEAD WILL LEAD TO RAPID DEEPENING OF THE SURFACE LOW AND THUS AN INCREASE IN WINDS BEHIND THE COLD FRONT LATE TONIGHT. DESPITE THE LOW LEVEL STABILIZATION... FORECAST SOUNDINGS SUGGEST PLENTY OF LINGERING MOISTURE IN THE 925-700 MB LAYER FOR LINGERING MOSTLY CLOUDY SKIES ESPECIALLY IN THE NORTHERN CWA OVERNIGHT. FOLLOWING HIGH-RES SHORT TERM GUIDANCE... EXPECT HIGHS TODAY FROM MID 60S NW TO MID 70S SE... NO BETTER THAN A 10-15 DEG F DIURNAL RANGE. LOWS TONIGHT 41 NW TO 48 SE. -GIH FROM 300 PM FRIDAY: THE FORECAST TRACK OF THE MID/UPPER SUNDAY WAS STILL VARIABLE WITHIN THE MODEL OUTPUT. THE CONSENSUS IS FOR A TRACK EASTWARD FROM THE CENTRAL APPALACHIANS ALONG OR NEAR THE NC/VA BORDER REGION DURING SUNDAY MORNING... THEN SHIFTING OFFSHORE SUNDAY AFTERNOON. WITH THIS TRACK... AND WITH THE SURFACE COLD FRONT EXPECTED TO BE OFFSHORE AROUND 12Z/SUNDAY... CENTRAL NC IS EXPECTED TO BE IN THE DRY SLOT BEGINNING AROUND DAYBREAK. THERE MAY STILL BE A RESIDUAL SHOWER CHANCE... MAINLY ALONG AND EAST OF I-95 EARLY IN THE MORNING. OTHERWISE... UNLESS THE MID LEVEL CIRCULATION COMES FARTHER SOUTH... THERE SHOULD BE LITTLE IN THE WAY OF RAIN CHANCES. BY AFTERNOON... NVA AND DOWNSLOPE SINKING IN THE MEAN WNW FLOW IN THE REAR OF THE STORM WILL LEAD TO CLEARING/WINDY/MILD CONDITIONS. HIGHS SUNDAY SHOULD TOP OUT IN THE LOWER 60S NW TO NEAR 70 IN THE SE. NW WINDS AT 15-25 MPH WITH GUSTS TO 30 MPH APPEAR LIKELY. -PWB && .SHORT TERM / /... AS OF 330 PM FRIDAY... TO BE UPDATED. && .LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/... AS OF 145 PM FRIDAY... SUNDAY NIGHT AND MONDAY WILL BRING CLEAR/SUNNY/MILD WEATHER AS HIGH PRESSURE (OF PACIFIC ORIGIN) MOVES OVERHEAD. LOWS 35-42. HIGHS 67- 72. TUESDAY THROUGH THURSDAY NIGHT... MID AND UPPER LEVEL RIDGING WILL LEAD TO A MUCH WARMER PERIOD FOR CONSECUTIVE DAYS. THE MAIN STORM TRACK FROM THE PLAINS TO THE GREAT LAKES INTO SE CANADA WILL BE FAR ENOUGH AWAY TO KEEP ANY POP OUT OF THE FORECAST. THE TEMPERATURES SHOULD WARM WELL INTO THE 70S (WITH LOWER 80S POSSIBLE IN THE SANDHILLS MID-WEEK) WITH THE LOW LEVEL SW FLOW. LOWS WARM FROM 40-45 TUE... INTO THE LOWER TO MID 50S THU. THE NEXT SIGNIFICANT WEATHER MAKER SHOULD HOLD OFF UNTIL THURSDAY NIGHT AND/OR FRIDAY ASSOCIATED WITH STORM TRACK FROM THE SOUTHERN PLAINS TO THE OHIO VALLEY... AND A TRAILING COLD FRONT THE SHOULD EDGE TO NEAR THE APPALACHIANS BY 12Z/FRIDAY... AND PUSH EAST ACROSS THE REGION FRIDAY. WE WILL PLACE A LOW END CHANCE POP IN THE FORECAST THU NIGHT AND FRIDAY WITH INCREASING CLOUDINESS. LOWS 55- 62. HIGHS FRIDAY GENERALLY 70-75 DEPENDING ON TIMING OF THE FRONT AND ASSOCIATED SHOWER CHANCES. && .AVIATION /06Z SATURDAY THROUGH WEDNESDAY/... AS OF 100 AM SATURDAY... POOR AVIATION CONDITIONS ARE EXPECTED TO PERSIST THROUGH AT LEAST 00Z TONIGHT... AND POTENTIALLY THROUGH THE END OF THE TAF VALID PERIOD AT 06Z. A DEEP MOIST FLOW FROM THE SOUTH AND SW... AHEAD OF A STRENGTHENING STORM SYSTEM NOW MOVING THROUGH MS AND WRN TN... WILL BRING IFR/LIFR CONDITIONS AND PERIODS OF MOSTLY LIGHT RAIN THROUGH DAYBREAK. WE SHOULD SEE A BRIEF BREAK OR LULL IN THE WIDESPREAD RAIN THROUGH MUCH OF THE MORNING HOURS... MOST LIKELY FROM 11Z TO 16Z... BUT CIGS ARE LIKELY TO REMAIN IFR WITH MVFR TO IFR VSBYS DURING THIS TIME. THEN STARTING SOON AFTER 16Z... A LINE OF SHOWERS AND THUNDERSTORMS IS EXPECTED TO SWEEP EAST-NORTHEAST THROUGH CENTRAL NC THROUGH THE AFTERNOON HOURS... BRINGING THE POTENTIAL FOR LOCALLY STRONG WIND GUSTS OVER 30 MPH... AND PERHAPS A FEW SEVERE STORMS. THESE STORMS ARE EXPECTED TO EXIT THE AREA TO OUR NORTHEAST AFTER 22Z... HOWEVER THE PASSAGE OF A COLD FRONT WITH AN UPPER LEVEL LOW CLOSE ON ITS HEELS WILL BRING A CONTINUED THREAT OF MVFR-IFR CIGS THROUGH THIS EVENING. WINDS WILL SHIFT TO BE FROM THE NW WITH THE COLD FRONT PASSAGE... BETWEEN 02Z AND 04Z AT INT/GSO AND BETWEEN 04Z AND 06Z AT RDU. LOOKING BEYOND 06Z TONIGHT... MVFR CIGS ARE EXPECTED TO DOMINATE THROUGH 18Z SUN. WINDS WILL BE BRISK AND GUSTY FROM THE NW THROUGHOUT SUNDAY... BRINGING A CROSSWIND THREAT MAINLY AT GSO/RDU. BETWEEN 18Z SUN AND 00Z MON... SLOW WEST-TO-EAST CLEARING IS EXPECTED AS THE UPPER LEVEL LOW MOVES SLOWLY THROUGH THE AREA... WITH AT TREND TO VFR AT INT/GSO/RDU LIKELY BY 00Z... AND AT RWI/FAY BETWEEN 00Z AND 06Z EARLY MON MORNING. VFR CONDITIONS ARE LIKELY FROM LATE SUN NIGHT THROUGH WED AS HIGH PRESSURE BUILDS INTO THE AREA FROM THE WEST. -GIH && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...HARTFIELD NEAR TERM...HARTFIELD/PWB SHORT TERM... LONG TERM...BADGETT AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
145 AM EDT SAT MAR 29 2014 .SYNOPSIS... A COLD FRONT EXTENDING FROM THE GREAT LAKES INTO TEXAS WILL MOVE INTO CAROLINAS EARLY SUNDAY MORNING. UNTIL THEN...RELATIVELY WARM AND HUMID AIR WILL STREAM NORTHWARD...ACCOMPANIED BY PERIODS OF SHOWERS AND THUNDERSTORMS. HIGH PRESSURE WILL FOLLOW THE COLD FRONT...BRINGING COOLER TEMPERATURES SUNDAY AND MONDAY. THE CENTER OF THE HIGH WILL MOVE OVERHEAD MONDAY NIGHT INTO TUESDAY. TEMPERATURES SHOULD CLIMB WELL ABOVE NORMAL FOR MUCH OF NEXT WEEK. A COLD FRONT MAY REACH THE AREA NEXT FRIDAY...BRINGING A RISK FOR SHOWERS. && .NEAR TERM /UNTIL 6 AM SATURDAY MORNING/... AS OF 1115 PM FRIDAY...UPDATE CONTINUES TO BE CONCERNED WITH MASSAGING THE OVERNIGHT HOURLY POPS. LATEST MOSAIC 88D RADAR TRENDS WILL BE MESHED WITH THE LATEST SREF MODEL PROBABILITY FOR OVERNIGHT MEASURABLE PCPN. THIS EVOLVED INTO MODIFYING THE HRLY POPS UP TO SEVERAL HRS AFTER DAYBREAK SAT. A COUPLE FAINT MID LEVEL VORTS OR S/W TROFS ALOFT TO PUSH ACROSS THE FA OVERNIGHT LENDING TO MODEST UVVS ACROSS THE FA ESPECIALLY DURING THE PRE-DAWN SAT HRS. LATEST HRRR MODEL GUIDANCE INDICATES A MORE WIDESPREAD PCPN SHIELD TO ENCOMPASS THE ILM CWA DURING THIS LATE EVENING THRU THE PRE-DAWN SAT HRS. HAVE ALSO INCREASED OVERNITE QPF BASED ON CURRENT OBSERVED ACTIVITY AND LATEST VARIOUS MODEL QPF OUTPUT. OVERNIGHT TEMPS MAINLY WILL HOLD STEADY OR EVEN SLIGHTLY INCREASE AS THE FA BECOMES BETTER ENTRENCHED IN THE WARM SECTOR AHEAD OF THE MAIN UPPER S/W TROF AND ASSOCIATED SFC LOW. PREVIOUS DISCUSSION..................................... AS OF 300 PM FRIDAY...A LARGE MCS ALONG THE EASTERN GULF COAST DOMINATES THE WEATHER PATTERN ACROSS THE SOUTHEASTERN U.S. THE CONVECTIVE ELEMENTS OF THIS FEATURE ARE LARGELY LIMITED TO SOUTHERN GEORGIA AND POINTS SOUTH...WITH AN EXPANSIVE BUT DETERIORATING AREA OF LIGHT RAIN EXTENDING INTO NORTH GEORGIA AND WESTERN SOUTH CAROLINA. THIS ACTIVITY SHOULD MOVE EASTWARD... AFFECTING THE SC PEE DEE REGION EARLY THIS EVENING. OTHER GENERALLY LIGHT SHOWERS DEVELOPING IN A WEAKLY UNSTABLE AIRMASS ACROSS THE EASTERN CAROLINAS MAY CONTINUE INTO THE EVENING HOURS AS WELL AS SMALL ELEVATED INSTABILITY IS MAINTAINED BY A SOUTHERLY FLOW ACROSS THE GULF STREAM OFF THE GEORGIA AND SOUTH CAROLINA COAST. THE UPPER LEVEL DISTURBANCE THAT HELPED KICK OFF THE GULF COAST MCS WILL TURN NORTHEASTWARD TONIGHT...APPROACHING THE EASTERN CAROLINAS LATE. WHILE A RENEWED BLOWUP OF CONVECTION IS NOT ANTICIPATED DUE TO MEAGER INSTABILITY...A DIFLUENT UPPER LEVEL PATTERN AND AN INCREASING NEGATIVE TILT TO THE TROUGH SHOULD ENHANCE RAIN/SHOWER POTENTIAL OVERNIGHT ALL THE WAY DOWN TO THE COAST. WHILE I CAN`T BRING MYSELF TO PUT 100 POPS IN THE FORECAST...80-90 PERCENT SEEMS APPROPRIATE. PRECIPITABLE WATER VALUES SHOULD GROW TO 1.5 INCHES AFTER MIDNIGHT. IN TERMS OF MODEL SOLUTIONS...IT IS INTERESTING TO SEE HOW THE MODELS HAVE HANDLED (OR MISHANDLED) TWO ASPECTS OF THE WEATHER TODAY. ONE IS THE RELATIVELY LIGHT WINDS OVER THE COASTAL WATERS... PARTICULARLY WHEN CONTRASTED TO THE RATHER BREEZY CONDITIONS EXPERIENCED INLAND TODAY. MOST SYNOPTIC GUIDANCE (PARTICULARLY THE GFS) HAS BEEN TOO STRONG WITH MARINE WIND SPEEDS ALL DAY. ALSO OF NOTE IS THE PERSISTENT AREA OF LIGHT SHOWERS THAT MOVED INTO GEORGETOWN THIS MORNING AND NOW COVERS BRUNSWICK COUNTY ACROSS WHITEVILLE INTO LUMBERTON AND ELIZABETHTOWN. THIS ACTIVITY HAS BEEN WELL-FORECAST BY THE HRRR AND NAM BUT NOT THE GFS. PREFERRED MODELS TONIGHT INCLUDE THE HRRR IN THE VERY NEAR-TERM...THEN THE 12Z NAM AND 12Z CANADIAN OVERNIGHT. WITH SOUTHERLY WINDS AND CLOUDS CONTINUING OVERNIGHT LOWS SHOULD ONLY FALL TO 59-60 INLAND WITH 57-58 NEAR THE BEACHES DUE TO WINDS BLOWING IN OFF THE COLDER NEARSHORE WATERS. THE NAM MOS GUIDANCE IS MUCH CLOSER TO MY IDEAS THAN THE GFS MOS. && .SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY NIGHT/... AS OF 300 PM FRIDAY...THE MAIN CHALLENGE CONTINUES TO CENTER AROUND THE COMPLEX STORM SYSTEM MOVING ACROSS THE SOUTHEAST. TIMING AND INTENSITY OF RAINFALL AND ASSOCIATED THUNDERSTORMS REMAIN THE MAIN ISSUES. I HAVE LEANED HEAVILY TOWARD THE GFS FOR THE LATEST UPDATES TO THE SHORT TERM. INITIALLY WE COULD HAVE A LARGE SWATH OF RAIN COMING OFF THE ATLANTIC. AFTER THIS...THERE SHOULD BE A LULL IF YOU WILL WITH SOME NVA IN THE WAKE OF THIS INITIAL FEATURE. THE MAIN SHORTWAVE FINALLY GETS ORGANIZED AND MOVES OFF TO THE EAST/NORTHEAST SATURDAY AFTERNOON WITH YET ANOTHER DEEP MOISTURE FEED FROM THE GULF OF MEXICO WITH THE ASSOCIATED COLD FRONT. I HAVE INCREASED POPS FOR LATE AFTERNOON ACROSS WESTERN AREAS AND THE EVENING HOURS FOR COASTAL SITES. SEVERE PARAMETERS REMAIN MARGINAL AND CONTINUE TO HINGE ON THE AMOUNT OF INSTABILITY THE IS ABLE TO DEVELOP. LARGE DIFFERENCES IN TEMPERATURE GUIDANCE WITH THE NAM/MET NUMBERS QUITE A BIT LOWER FOR DAYTIME HIGHS SATURDAY. I WOULD EXPECT ANY BREAKS AND THERE SHOULD BE AT LEAST A FEW WILL ALLOW HIGHS TO JUMP MORE TOWARD THE GFS/MAV NUMBERS. GUIDANCE TRENDS CLOSER SATURDAY NIGHT AND SUNDAY. && .LONG TERM /MONDAY THROUGH FRIDAY/... AS OF 300 PM FRIDAY...THE LONG TERM APPEARS TO OFFER RAIN-FREE WEATHER. AS FAR AS TEMPERATURES GO DAYTIME HIGHS WILL AVERAGE ABOUT A CATEGORY ABOVE CLIMO WHILST NIGHTTIME LOWS SHOULD BE EVEN MILDER. HIGH PRESSURE SLIDES INTO FLORIDA ON MONDAY KEEPING LOCAL WINDS RATHER LIGHT. MEANWHILE UPPER RIDGING BUILDS IN FROM THE WEST. TUESDAY THROUGH WEDNESDAY WILL SHIFT THE HIGH SLIGHTLY EASTWARD WHILE THE UPPER LEVEL WAVE FLATTENS. END RESULT WILL BE A SLIGHT BOLSTERING OF THE WARM ADVECTION INTO THE REGION. UPPER LEVEL AMPLITUDE WILL THEN INCREASE AGAIN THURSDAY INTO FRIDAY AS A STORM SYSTEM MOVES OUT OF THE ROCKIES AND DEVELOPS INTO THE PLAINS THURSDAY...MOVING INTO OHIO VALLEY COME FRIDAY. && .AVIATION /06Z SATURDAY THROUGH WEDNESDAY/... AS OF 06Z...EXPECT MVFR/IFR THROUGH THE OVERNIGHT HOURS...WITH BRIEF INTERMITTENT PERIODS OF VFR POSSIBLE...AS VARYING LOW CIGS AND RAIN AND AREAS OF HEAVIER SHOWERS MOVE THROUGH THE AREA. MIX OF MVFR/IFR CONTINUES ON SATURDAY AS LOW TO MID CLOUDS...SHOWERS...AND ISOLATED TO SCATTERED THUNDERSTORMS MOVE THROUGH...GRADUALLY IMPROVING TO VFR TOWARDS THE END OF THE PERIOD. LATEST RADAR IMAGERY CONTINUES TO HIGHLIGHT WIDESPREAD RAIN WITH SCATTERED HEAVIER SHOWERS. CONFIDENCE IS HIGH THROUGH THE OVERNIGHT HOURS REGARDING MVFR AND IFR CONDITIONS...BUT HAVE KEPT PREVAILING MVFR WITH PERIODS OF IFR AS VARYING LOWERED CIGS MOVE ACROSS THE AREA. ALSO EXPECT REDUCED VISIBILITIES DUE TO AREAS OF FOG AND SHOWERS. AFTER DAYBREAK...EXPECT MVFR WITH IFR POSSIBLE THROUGH THE MORNING HOURS...ALONG WITH WIDESPREAD RAINFALL AND ISOLATED THUNDERSTORMS. STRONGER STORMS ARE POSSIBLE IN THE AFTERNOON/EVENING HOURS. SOUTHERLY WINDS WILL PREVAIL WITH SUSTAINED WINDS AOB 12 KTS AND PERIODIC GUSTS POSSIBLE THROUGHOUT THE DAY...ESPECIALLY IN STRONGER STORMS...AROUND 20 KTS OR SLIGHTLY HIGHER. TOWARDS THE END OF THE PERIOD...COULD SEE SOME IMPROVEMENT TO VFR WITH CONVECTION GRADUALLY TAPERING OFF. EXTENDED OUTLOOK...BECOMING VFR OVERNIGHT SATURDAY INTO SUNDAY. SLIGHT CHANCE FOR SHOWERS AND MVFR CEILINGS OVER THE NORTHERN PORTION OF THE CWA. OTHERWISE VFR THROUGH WEDNESDAY. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 1115 PM FRIDAY...THIS UPDATE REMAINS MORE CONCERNED WITH THE INCREASED POTENTIAL FOR SEA FOG...AND THE ASSOCIATED POTENTIAL VISIBILITY DROPPING BELOW 1 NM. THIS A RESULT OF 60+ SFC DEW POINTS PUSHING ACROSS SHELF WATER SSTS IN THE LOW TO MID 50S. HAVE CONTINUED THE OVERALL ONSHORE WIND REGIME FROM THE PREVIOUS FORECAST...WITH THE PROGGED SFC PRESSURE PATTERN AND GRADIENT KEEPING WINDS FROM THE SSE-S AT 10 TO 15 KT WIND SPEEDS. WAA WINDS TOUGH TO MIX DOWN TO THE OCEAN SURFACE EXHIBITING 50 DEGREE SSTS. HOWEVER...THE SFC PG IS EXPECTED TO FURTHER TIGHTEN BUT NOT UNTIL THE MAIN SFC LOW AND COLD FRONT PUSH CLOSER TO THE FA DURING DAYLIGHT SATURDAY. SIGNIFICANT SEAS HAVE STABILIZED LATE THIS EVENING BUT SHOULD BEGIN TO TREND SLIGHTLY HIGHER BY OR JUST AFTER DAYBREAK SATURDAY. BUILDING WIND DRIVEN WAVES JUST OFFSHORE... HAVING BEEN CREATED BY THE HIER SE-S WINDS JUST OFFSHORE OVER THE MUCH WARMER SSTS...WILL PUSH INTO THE LOCAL WATERS AND MESH WITH THE LOCAL WAVES. SCA REMAINS BONAFIDE FOR THE REMAINDER OF TONIGHT...WITH SIGNIFICANT SEAS THE PRIMARY REASON. PREVIOUS DISCUSSION..................................... AS OF 300 PM FRIDAY...SOUTH WINDS SHOULD CONTINUE OVERNIGHT AS THE CAROLINAS ARE IN BETWEEN HIGH PRESSURE WELL OFFSHORE AND AN APPROACHING COLD FRONT OVER THE MISSISSIPPI VALLEY. THE GFS MODEL HAS BEEN TOO STRONG WITH WIND SPEEDS ALL DAY...BUT A COMBINATION OF THE 12Z NAM AND CANADIAN MODELS SEEMS LIKE A GOOD FIT. SOUTH WINDS 10-15 KNOTS WILL RAISE A SHORT-PERIOD WIND WAVE...BUT STRONGER WINDS OFFSHORE WILL CREATE LARGER WAVES THAT WILL PUSH WESTWARD INTO THE COASTAL WATERS AS WELL. THE COMBINATION SHOULD CREATE 4-6 FOOT SEAS WITH A 6 SECOND DOMINANT PERIOD...AND A SMALL CRAFT ADVISORY WILL REMAIN IN EFFECT FOR THIS. WAVES OF SHOWERS ARE EXPECTED ACROSS THE WATERS...WITH HEAVIER ACTIVITY POSSIBLE OVERNIGHT. PM FRIDAY... SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/... AS OF 300 PM FRIDAY...FAIRLY BRISK CONDITIONS WILL PREVAIL OVER THE WATERS THROUGH THE PERIOD. FOR SATURDAY...A SOUTHERLY FLOW OF 15-20 KNOTS WILL BE IN PLACE AS LOW PRESSURE AND A COLD FRONT EDGE CLOSER FROM THE WEST. THIS FRONT CROSSES THE WATERS BETWEEN 0600 AND 1200 UTC SUNDAY. WINDS WILL TURN FROM THE WEST AND INCREASE TO 20-25 KNOTS. WITH COLD AIR ADVECTION DEVELOPING SUNDAY...THE WINDS WILL REMAIN ELEVATED BUT HOPEFULLY NOT THE LEVEL WE SAW EARLIER IN THE WEEK TO GALE CRITERIA. BY MONDAY MORNING THERE IS A SLOW DECREASE TO AROUND 15 KNOTS. SIGNIFICANT SEAS WILL HOVER AROUND SMALL CRAFT CRITERIA AND I WILL GO AHEAD AND EXTEND THE ADVISORY TO COVER SATURDAY AND SATURDAY NIGHT. THE CHANGE IN FETCH SHOULD EVENTUALLY ALLOW THE ADVISORY TO EXPIRE SUNDAY. LONG TERM /MONDAY THROUGH WEDNESDAY/... AS OF 300 PM FRIDAY...MONDAY STARTS WITH A MODERATE NW FLOW A RESULT OF BOTH DEEPENING STORM MOVING UP THE MIDATLANTIC COAST AND HIGH PRESSURE BUILDING IN FROM THE WEST. AS BOTH PROGRESS EASTWARD THE LOCAL GRADIENT SHOULD REALLY EASE AS THE DAY WEARS ON AND BY MONDAY NIGHT THERE MAY BE A LIGHT ENOUGH GRADIENT FOR A TRUE LIGHT AND VARIABLE WIND. TUESDAY INTO WEDNESDAY THE HIGH TAKES A MORE OFFSHORE POSITION GENERATING A LIGHT S TO SW FLOW LOCALLY. SEAS BUILD FROM THEIR MINIMAL MONDAY NIGHT VALUES TO ABOUT 2 TO 3 FT. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 7 AM EDT SUNDAY FOR AMZ250- 252-254-256. && $$ NEAR TERM...DCH/TRA SHORT TERM...SHK LONG TERM...MBB AVIATION...SGL/RJD
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1131 PM EDT SUN MAR 30 2014 .SYNOPSIS... A DEEPENING STORM ON THE NJ COAST MOVE VERY SLOWLY EAST OVERNIGHT. A RIDGE OF HIGH PRESSURE WILL SLIDE OVERHEAD ON MONDAY AND LEAD TO FAIR AND MILDER TEMPERATURES FOR THE FIRST HALF OF THE WEEK. UNSETTLED CONDITIONS ARE EXPECTED TO RETURN FOR THE SECOND HALF OF THE WEEK. && .NEAR TERM /THROUGH MONDAY/... 10PM UPDATE... LIKE A BROKEN RECORD...WE KEEP WATCHING THE SNOW/RAIN/SLEET REPEAT OVER THE SAME AREAS UNDER THE BAND FROM EASTERN SULLIVAN COUNTY DOWN TO THE MARYLAND BORDER. THE EMBEDDED ECHOES ARE A BIT WEAKER OVER THE LAST COUPLE OF HOURS...AND THE TREND TOWARD WEAKENING AND SHRINKING SHOULD CONTINUE AS DEPICTED BY THE FADING FRONTOGENETIC FORCING BEING PORTRAYED IN THE RAP OUTPUT. WHILE MOST OF THE PRECIP IS FALLING AS RAIN...WE HAVE ENOUGH LOCATIONS SEEING ACCUMULATING WET SNOW TO WARRANT KEEPING THE ADVISORY. THIS HAS BEEN AN EXTREMELY COMPLEX SYSTEM TO GRAPPLE WITH AS PRECIP RATES AND ELEVATIONS HAVE HAD MUCH TO DO WITH WHERE THE SNOW FELL HARD ENUF TO ACCUMULATE. IT WILL REMAIN BREEZY OVERNIGHT...WITH GUSTS IN THE 25-35 MPH RANGE COMMON. && .SHORT TERM /MONDAY NIGHT THROUGH 6 PM MONDAY/... HIGH PRESSURE RIDGE BUILDS IN BEHIND THE STORM FOR MONDAY. RESIDUAL MSTR WILL PROBABLY HOLD CLOUDS IN THE WRN MTS AT FIRST...BUT CLEARING SHOULD OCCUR EVERYWHERE THROUGH THE AFTERNOON. TEMPS SHOULD RECOVER VERY NICELY AS 8H TEMPS SHOOT BACK INTO THE MID SINGLE DIGITS ABOVE ZERO. AREAS WITH SNOW ON THE GROUND MAY HAVE A BIT OF A DELAY IN THE RECOVERY...BUT ALMOST- APRIL SUNSHINE SHOULD DO SOME GOOD MELTING. && .LONG TERM /MONDAY NIGHT THROUGH SUNDAY/... HIGH PRESSURE WILL CONTINUE TO BUILD OVER THE NORTHEAST MONDAY NIGHT INTO TUESDAY. A LARGE UPPER LEVEL LOW WILL MOVE THROUGH SOUTHERN CANADA/GREAT LAKES REGION TUESDAY EVENING. THIS SYSTEM CONTINUES TO BE MOISTURE STARVED SO PRECIPITATION IS LESS LIKELY. WEAK SOUTHWESTERLY FLOW COULD ALLOW FOR A SLIGHT CHANCE FOR PRECIPITATION ALONG THE SW MTNS...HOWEVER THIS IS LESS LIKELY CONSIDERING ANY LINGERING HIGH PRESSURE. A STATIONARY BOUNDARY BETWEEN THE SYSTEMS SHOULD LIE OVER THE REGION WEDNESDAY INTO EARLY THURSDAY. THIS COULD ALLOW...FOR PERIODS OF LIGHT SHOWERS. A WEAK RIDGE COULD STIFLE PRECIP EARLY THURSDAY. A DEEPENING UPPER LEVEL LOW WILL MOVE THROUGH THE MIDWEST THURSDAY NIGHT INTO FRIDAY...AND THROUGH THE REGION SATURDAY. THIS SYSTEM WILL BRING THE NEXT BEST CHANCE FOR PRECIPITATION. THERE IS STILL VARIATION ON POSITION AND TIMING...BUT RAIN SHOWERS ARE POSSIBLE AS EARLY AS THURSDAY AFTERNOON AS THE ASSOCIATED WARM FRONT NOSES INTO PENNSYLVANIA. THE COLD FRONT WILL MOVE THROUGH THE AREA DURING THE FIRST PART OF THE WEEKEND BRINGING MORE RAIN. INTO LATE SATURDAY. && .AVIATION /03Z MONDAY THROUGH FRIDAY/... 31/03Z UPDATE...IR STLT LOOP SHOWS GRADUAL W-E CLEARING TREND OVER ZOB SECTOR TAFS. CIGS HAVE COME UP TO HIGH MVFR/LOW VFR OVER CNTRL SITES...WITH THE LOWEST CONDS STILL PERSISTING AT MDT/LNS WHERE NARROW RAIN/SNOW BAND ON BACKSIDE OF DEPARTING OFFSHORE LOW CONTINUES TO IMPACT SERN PA. LATEST HI-RES MODELS SHOW THIS BAND WEAKENING AND SHIFTING EWD AFT 09Z. THIS ANTICIPATE CLEARING TO EXPAND EWD LATE TNGT INTO EARLY MONDAY. STIFF NNW WINDS WILL GRADUALLY WEAKEN FROM W TO EAST BY MONDAY EVE...AS HIGH PRESSURE SLOWLY MIGRATES EWD FROM THE OH VLY. OUTLOOK... MON...LOW CIGS RAIN/SNOW ENDING ERN SXNS EARLY BCMG VFR. VFR ELSEWHERE. TUE...VFR WITH OCNL MVFR PSBL IN SCT SHRA ASSOC WITH COLD FRONT. WED-FRI...PERIODS OF RAIN AND ASSOC LOW CIGS/VIS LKLY AS FRONTAL BOUNDARY BECOMES STATIONARY INVOF THE AIRSPACE. && .HYDROLOGY... WILL ALLOW THE FLOOD WATCH FOR THE SERN ZONES TO EXPIRE ON SCHEDULE /1 AM/. WILL CUT BACK AREA OF FLS TO JUST YORK COUNTY BUT EXTEND THE END TIME...BASED ON NON-FCST POINT TRACES STILL WELL-ABOVE ACTION STAGES. MAINSTEM SUSQ RIVER POINTS ARE FCST CREST NEAR OR A FEW FEET ABOVE CAUTIONARY STAGES. ONLY POINT IN FLOOD IS YELLOW BREECHES CREEK WHICH IS FCST TO CREST JUST BELOW MODERATE FLOOD STAGE /9FT/ OVERNIGHT. && .CTP WATCHES/WARNINGS/ADVISORIES... FLOOD WATCH UNTIL 1 AM EDT MONDAY FOR PAZ057>059-065-066. WINTER WEATHER ADVISORY UNTIL 1 AM EDT MONDAY FOR PAZ042- 051>053-057>059-064>066. && $$ SYNOPSIS...LAMBERT NEAR TERM...LAMBERT SHORT TERM...DANGELO/LAMBERT LONG TERM...CERU/COLBERT AVIATION...STEINBUGL HYDROLOGY...STEINBUGL
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
753 PM EDT SUN MAR 30 2014 .SYNOPSIS... A DEEPENING STORM ON THE NJ COAST MOVE VERY SLOWLY EAST OVERNIGHT. A RIDGE OF HIGH PRESSURE WILL SLIDE OVERHEAD ON MONDAY AND LEAD TO FAIR AND MILDER TEMPERATURES FOR THE FIRST HALF OF THE WEEK. UNSETTLED CONDITIONS ARE EXPECTED TO RETURN FOR THE SECOND HALF OF THE WEEK. && .NEAR TERM /UNTIL 8 PM THIS EVENING/... 445PM UPDATE... RAPID CHANGES TAKING PLACE AS THE INTENSE MESOSCALE BAND OF PRECIP IS GENERATING JUST ENOUGH COLD AIR TO CREATE LOCALLY HEAVY SNOW. WEB CAMS AND REPORTS WARRANT THE ISSUANCE OF AN ADVISORY INTO THE EVENING AS CONDITIONS VARY WILDLY FROM NOTHING AT ALL HAPPENING OVER MOST OF CENTRAL AND WESTERN PA...TO HEAVY SNOW AND SLEET AND RAIN OVER ABOUT THE EASTERN 1/3 OR SO OF OUR FORECAST AREA. THE SLOW MOVING BAND OF RAIN-SNOW-SLEET WILL CONTINUE TO ONLY SLOWLY DRIFT OVER MY EASTERN ZONES. WHERE PRECIP RATES ARE INTENSE ENOUGH...SOME LOCALLY HEAVY SNOW IS BEING OBSERVED. STILL THINKING MOST OF THE SNOW SHOULD BE CONFINED TO GRASSY SURFACES...BUT THE ROADS WILL BE SLIPPERY AND SLUSHY IN THE MORE PERSISTENT HEAVY SNOW BANDS. FROM EARLIER... REGIONAL RADAR MOSAIC AT 19Z SHOWS AN EXTENSIVE...AND NEARLY STATIONARY BAND OF MODERATE TO HEAVY RAIN OVER THE SUSQ MAINSTEM /AND POINTS WEST TO INTERSTATE 81 ACROSS SCENT PENN/ THIS AREA OF PERSISTENT/HEAVY PRECIP IS OCCURRING AS A RESULT OF THE COMBINED EFFECTS OF A MODERATELY STRONG DEFORMATION BAND AND MID-LEVEL FGEN FORCING /ENHANCED BY A WELL-DEFINED SPOKE OF VORTICITY SPIRALING AROUND THE NWRN EDGE OF THE SLOW MOVING UPPER LOW CENTERED OVER THE DELMARVA PENINSULA/. FLOOD WATCH REMAINS IN EFFECT UNTIL 8 PM THIS EVENING FOR THE EASTERN HALF OF THE STATE WHILE THE LOCALIZED VERY HEAVY RAIN ACROSS PORTIONS OF SCENT PENN HAVE PROMPTED US TO UPGRADE OUR EARLIER FLOOD ADVISORY TO A FLOOD WARNING FOR ADAMS AND YORK COUNTIES...WITH THE YELLOW BREECHES CREEK AT CAMP HILL FORECAST TO EXCEED FS TONIGHT. DEEP LAYER CAA WILL HELP TO GRADUALLY MIX...THEN CHANGE THE RAIN OVER TO WET SNOW ACROSS EVEN THE SOUTHERN VALLEYS LATE THIS AFTERNOON AND EARLY THIS EVENING...WHILE A GRADUAL DECREASING TREND IN THE LIGHTER SNOW OCCURS ACROSS THE NRN AND WESTERN MTNS OF THE STATE. CANCELLED THE WINT WX ADVISORY FOR ALL BUT SULLIVAN COUNTY...WHICH STILL RUNS THROUGH 4 PM TODAY. THIS MAY NEED TO BE EXTENDED A FEW HOURS BASED ON THE LATEST 18Z RAP. 15Z/18Z RAP DOING AN EXCELLENT JOB SIMULATING THIS NEARLY STATIONARY/SLOWLY WWD DRIFTING BAND OF HEAVIER PRECIP SWIRLING AROUND THE 546 DAM UPPER LOW. THESE MODELS SHOW A TREND OF MAINTAINING THIS RATHER HIGH RAINFALL INTENSITY /AND RATE OF AT LEAST .3 TO .6 OF AN INCH PER HOUR/ BEFORE CHANGING IT TO A FEW TO SVRL HOUR PERIOD OF /WET/ SNOW EARLY THIS EVENING...THEN SLOWLY WEAKENING THE PRECIP RATES AND SLOWLY SHIFTING THE AREA EAST ACROSS THE LOWER SUSQ REGION AND ECENT MTNS TONIGHT. ADDITIONAL QPF /LIKELY BETWEEN 0.5-1.0 INCH OF ADDITIONAL RAIN AND MELTED WET SNOW ACROSS THE SCENT ZONES AND LOWER SUSQ REGION/ WILL GRADUALLY TREND LOWER...THEN DIMINISH QUICKLY AS YOU HEAD NW TWD THE I-99/RT 220 CORRIDOR. THIS WILL LEAD TO A RAIN/WET SNOW MIXTURE WITH LITTLE OR NO ACCUM AT ELEVATIONS AOB 1400 FT MSL. MAINLY RAIN /MDT TO HVY AT TIMES/ WILL PERSIST ACROSS THE LOWER SUSQ VALLEY THROUGH THE LATE AFTERNOON WITH BIG...SLOPPY WET SNOWFLAKES MIXING IN TO THE WEST OF I-83. TEMPS ALOFT REMAIN JUST WARM ENOUGH FOR ALL RAIN IN THE FAR SE INVOF KLNS. SOME OF THE HIGHER TERRAIN OF SCENT...AND ECENT PENN /MAINLY AOA 1400 FT MSL/ COULD START TO SEE A GROUND COVERING OF WET SNOW LATER THIS AFTERNOON AND EVENING AS A FEW ADDITIONAL SPOKES OF VORTICITY AND N/S PRECIP BANDS ROTATE WWD AROUND THE UPPER LOW. 2-DAY STORM TOTAL RAINFALL AND MELTED SNOW BY MIDNIGHT TONIGHT HAVE REACHED 4-5 INCHES OVER PORTIONS OF SCENT PENN /ADAMS AND YORK COUNTIES/...JUST WEST OF THE SUSQ RIVER...WHILE OTHER LOCATIONS THROUGHOUT EASTERN CENTRAL AND EASTERN SECTIONS OF THE CWA COME IN BETWEEN 1.5 AND 2.5 INCHES. WET SNOW WILL CONTINUE TO TAPER OFF IN THE WEST THROUGH THIS AFTERNOON AS THE CENTER OF THE UPPER LOW MOVES FARTHER TO THE EAST AND SIGNIFICANT LIFT EXITS WITH IT. THE OTHER INCREASINGLY NOTABLE ASPECT OF THE WEATHER WILL BE THE GUSTY 30-40 MPH WIND THAT WILL BE DEVELOPING IN THE STRENGTHENING LLVL PRESSURE GRADIENT JUST IN THE WAKE OF THIS CURRENT SYSTEM. && .SHORT TERM /8 PM THIS EVENING THROUGH 6 PM MONDAY/... RAIN AND WET SNOW WILL CONTINUE INTO THE NIGHT OVER THE FAR EAST...WITH MINOR ACCUMS OF A COATING TO ONE INCH /PERHAPS 2 INCHES ON THE RIDGES AOA 1600 FT MSL FROM SCHUYLKILL CTY...NORTH TO SULLIVAN CTY. HIGH PRESSURE RIDGE BUILDS IN BEHIND THE STORM FOR MONDAY. RESIDUAL MSTR WILL PROBABLY HOLD CLOUDS IN THE WRN MTS AT FIRST...BUT CLEARING SHOULD OCCUR EVERYWHERE THROUGH THE AFTERNOON. TEMPS SHOULD RECOVER VERY NICELY AS 8H TEMPS SHOOT BACK INTO THE MID SINGLE DIGITS ABOVE ZERO. AREAS WITH SNOW ON THE GROUND MAY HAVE A BIT OF A DELAY IN THE RECOVERY...BUT ALMOST- APRIL SUNSHINE SHOULD DO SOME GOOD MELTING. && .LONG TERM /MONDAY NIGHT THROUGH SUNDAY/... HIGH PRESSURE WILL CONTINUE TO BUILD OVER THE NORTHEAST MONDAY NIGHT INTO TUESDAY. A LARGE UPPER LEVEL LOW WILL MOVE THROUGH SOUTHERN CANADA/GREAT LAKES REGION TUESDAY EVENING. THIS SYSTEM CONTINUES TO BE MOISTURE STARVED SO PRECIPITATION IS LESS LIKELY. WEAK SOUTHWESTERLY FLOW COULD ALLOW FOR A SLIGHT CHANCE FOR PRECIPITATION ALONG THE SW MTNS...HOWEVER THIS IS LESS LIKELY CONSIDERING ANY LINGERING HIGH PRESSURE. A STATIONARY BOUNDARY BETWEEN THE SYSTEMS SHOULD LIE OVER THE REGION WEDNESDAY INTO EARLY THURSDAY. THIS COULD ALLOW...FOR PERIODS OF LIGHT SHOWERS. A WEAK RIDGE COULD STIFLE PRECIP EARLY THURSDAY. A DEEPENING UPPER LEVEL LOW WILL MOVE THROUGH THE MIDWEST THURSDAY NIGHT INTO FRIDAY...AND THROUGH THE REGION SATURDAY. THIS SYSTEM WILL BRING THE NEXT BEST CHANCE FOR PRECIPITATION. THERE IS STILL VARIATION ON POSITION AND TIMING...BUT RAIN SHOWERS ARE POSSIBLE AS EARLY AS THURSDAY AFTERNOON AS THE ASSOCIATED WARM FRONT NOSES INTO PENNSYLVANIA. THE COLD FRONT WILL MOVE THROUGH THE AREA DURING THE FIRST PART OF THE WEEKEND BRINGING MORE RAIN. INTO LATE SATURDAY. && .AVIATION /00Z MONDAY THROUGH FRIDAY/... A STRONG/SLOW-MOVG DEEP LAYER SFC-UPPER LOW CENTER WILL SLOWLY MOVE AWAY FROM THE MID-ATLC COAST TNGT INTO MONDAY. A NARROW BAND OF MIXED PCPN ALONG WITH BROADER AREA OF LOW CIGS WILL ALSO SHIFT SLOWLY EWD IN TIME...WITH CLEARING /TO VFR/ EXPECTED ACRS WRN SXNS IN ZOB SECTOR BY 03-04Z. THE CNTRL AND PARTICULARLY ERN TAFS WILL TAKE THE LONGEST TO CLR WITH RA/SN/PL MIXED PTYPES IMPACTING MDT AND (TO A LESSER EXTENT) LNS THRU 06-07Z AND LOW CIGS PERHAPS UNTL 14-15Z. NNW WINDS WILL GRADUALLY WEAKEN FROM W TO EAST THRU THE DAY ON MONDAY...AS HIGH PRESSURE SLOWLY MIGRATES EWD FROM THE OH VLY. OUTLOOK... MON...LOW CIGS RAIN/SNOW ENDING ERN SXNS EARLY BCMG VFR. VFR ELSEWHERE. TUE...VFR WITH OCNL MVFR PSBL IN SCT SHRA ASSOCD WITH COLD FRONT. WED-FRI...PERIODS OF RAIN AND ASSOCD LOW CIGS/VIS LKLY AS FRONTAL BOUNDARY BECOMES STATIONARY NEAR OR SOUTH OF THE AIRSPACE. && .HYDROLOGY... FLOOD WATCH CONTINUES FOR ABOUT EASTERN THIRD OF CWA THROUGH THIS EVENING. THE CLOSED UPPER LOW IS EXPECTED TO CLOSE TRACK SLOWLY TO THE EAST AND OFF MID ATLC COAST LATE TODAY AND TONIGHT. THIS WILL PRODUCE A FEW MORE NWWD BANDS OF MDT TO HEAVY RAIN OVER SCENT AND EASTERN PENN TODAY. THE HIGHER AMOUNTS STILL LOOK TO BE FOCUSED ACROSS THE SCENT MTNS...LOWER SUSQ VALLEY AND ECENT MTNS...AS THE DEFORMATION ZONE TO THE N/W OF THE UPPER LOW CENTER MOVES TO THE EAST AS WELL. THE RAIN MAY NOT MOVE OUT ENTIRELY UNTIL MIDNIGHT OR LATER. THUS...THE WATCH MAY NEED TO BE EXTENDED TO COVER THE PERIOD OF RUNOFF. BUT HAVE NOT MADE THIS MOVE QUITE YET. LOCALIZED STORM TOTAL AMOUNTS OF UP TO 2 INCHES ARE LIKELY OVER THE EAST. THIS WILL CAUSE SIGNIFICANT RISES ON THE SMALL STREAMS AND SOME MAY BE RISING TO BANKFULL BEFORE NOON. MANY OF THE LARGER WATERWAYS MAY GET TO THEIR CAUTION STAGES...BUT THESE EFFECTS WOULD BE DELAYED FOR A PERIOD OR TWO. THE MAINSTEM RIVER IS ALREADY PROGGED TO REACH CAUTION STAGES AT MANY PLACES WITH CURRENT QPF IN THE HYDRO MODEL. MMEFS PROBS FOR EXCEDENCE MAY BE UNDERDONE IN THE SREF DATA...MAINLY DUE TO THE SHIFTING QPF AREAS/CENTERS AMONGST THE MEMBERS. && .CTP WATCHES/WARNINGS/ADVISORIES... FLOOD WATCH UNTIL 1 AM EDT MONDAY FOR PAZ057>059-065-066. WINTER WEATHER ADVISORY UNTIL 1 AM EDT MONDAY FOR PAZ042- 051>053-056>059-063>066. && $$ SYNOPSIS...LA CORTE/LAMBERT NEAR TERM...LA CORTE/LAMBERT SHORT TERM...DANGELO/LAMBERT LONG TERM...CERU/COLBERT AVIATION...STEINBUGL HYDROLOGY...LAMBERT
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
115 PM EDT SAT MAR 29 2014 .SYNOPSIS... A WAVE OF LOW PRESSURE WILL FORM OVER KENTUCKY AND TENNESSEE AND MOVE TO THE DELMARVA REGION BY TONIGHT. THE ASSOCIATED UPPER LEVEL TROUGH WILL GET DEEPER...SLOWING DOWN THE SYSTEM SIGNIFICANTLY. MILDER TEMPERATURES BUT CONTINUED UNSETTLED CONDITIONS ARE EXPECTED FOR NEXT WEEK. && .NEAR TERM /UNTIL 8 PM THIS EVENING/... WINTER WEATHER ADVISORY RECENTLY ISSUED FOR WARREN...MCKEAN AND POTTER COUNTIES 8 PM THIS EVENING TO NOON SUNDAY. WORDED FCST AND GRIDDED FIELDS TRACKING PRETTY MUCH AS EXPECTED. THE NW EDGE OF A LARGE SHIELD OF STEADY LIGHT TO MODERATE RAIN CONTINUES TO DRIFT NORTHWARD ACROSS THE LOWER SUSQ VALLEY...WHILE AREAS OF LIGHT RAIN/SHOWERS BLOSSOM/ADVECT NWD INTO SCENT PENN AND THE LAURELS. THIS WILL BE A LONG-DURATION PRECIP EVENT FOR MOST OF THE CWA...LASTING BETWEEN 36-48 HOURS. THE BULK OF THE PRECIP WILL FALL AS RAIN OF VARYING INTENSITY...BUT LATER SECTIONS OF THIS DISCUSSION WILL COVER THE WINTRY ASPECTS OF THIS SLOW-MOVING WEATHER SYSTEM /EXPECTED TO IMPACT THE HIGHER TERRAIN OF THE NORTH AND WEST AS WE HEAD INTO TONIGHT AND SUNDAY/. FOR THE NEAR TERM...POCKETS OF EARLIER SUNSHINE NEAR AND JUST TO THE NORTH OF I-80 HAVE VANISHED WITH THICK...LAYERED CLOUDS AND AREAS OF RAIN SPREADING IN FROM THE SOUTH. 12Z 13KM RAP AND 09Z SREF INDICATE THAT MUCH OF CENTRAL AND NRN PENN WILL STAY DRY UNDER MAINLY A MID CLOUD DECK THROUGH 18-20Z BEFORE THE RAIN ENCROACHES FROM THE SW AND SE. PRACTICALLY ALL LOCATIONS IN THE CWA SHOULD SEE RAIN BY 23Z TODAY...WITH THE HIGHEST TOTALS /BETWEEN 0.25-0.50 OF AN INCH/ OCCURRING ACROSS THE LAURELS...AND FAR SERN COUNTIES. 16Z TEMPS RANGE FROM NEAR 40F ACROSS THE NW MTNS...TO THE MID AND UPPER 40S ELSEWHERE...AND WILL HOLD FAIRLY STEADY FOR THE REST OF THE AFTERNOON /BUT SHOULD BEGIN TO SLOWLY SLIDE THROUGH THE 30S ACROSS THE NW MTNS AFTER 20Z/. && .SHORT TERM /8 PM THIS EVENING THROUGH 6 PM SUNDAY/... THE STORM DEEPENS RAPIDLY AS IT MOVES OVER THE MID-ATLANTIC STATES. THE UPPER LEVEL TROUGH CUTS OFF AND THE WIND PULLS IN LOTS OF MOISTURE...MAINLY FROM THE SOUTH/GOMEX. BUT THE SYSTEM ALMOST STALLS OVERHEAD. THIS WILL CREATE HEAVY RAIN FOR MUCH OF THE AREA...BUT MAINLY OVER THE EAST WHERE FLOOD WATCH IS ALREADY IN EFFECT. SEE HYDRO SECTION FOR MORE ON WATER ISSUES. THE OTHER TROUBLE WITH THE PRECIP IS THAT THE TEMPS SLOWLY DROP IN THE EVENING /AND ESPECIALLY OVERNIGHT/ ACROSS THE NRN AND WRN MTNS. THUS...THE NORTHWESTERN COUNTIES AND HIGHER ELEVATION IN THE CENTRAL MTNS WILL LIKELY SEE THE RAIN TURN TO A FEW-0SEVERAL HOUR PERIOD OF FZRA...A SHORTER PERIOD OF SLEET...THEN EVENTUALLY ACCUMULATING WET SNOW LATE TONIGHT AND SUNDAY MORNING WITH 2-4 INCHES LIKELY. THE INITIAL FREEZING RAIN /FROM WARREN COUNTY EAST TO POTTER COUNTY/...COULD ACCUMULATE UP TO ONE-QUARTER OF AN INCH IN SOME AREAS AS NEAR SFC TEMPS COOL BELOW FREEZING...PRIOR TO THE ZERO C ISOTHERM ARRIVING IN THE 925-850 MB LAYER/. TEMPS DO NOT SEEM TO EVER GET AOB FZG IN THE RIDGE AND VALLEY REGION SO...WILL JUST GO WITH A GRADUAL CHANGE/MIX HERE. QPF IN THE NORTHWEST AFTER THE CHANGE TO SNOW IS A VERY DIFFICULT PART OF THE FCST. IN GENERAL...THE EXPECTATION IS THAT THE HEAVY PRECIP WILL BE TO THE EAST BY LATE TONIGHT...AND THAT SHOULD LIMIT THE UPPER END OF THE SNOW ACCUMS TO 3 OR 4 INCHES /WHICH AGREES WELL WITH A BLEND OF THE 09Z SREF AND 12Z NAM 24-HOUR SNOW ACCUMS/. BIG FOCUS AND COORDINATION OVER THE NEXT FEW HOURS WILL CONCERN THE POTENTIAL FOR SEVERAL /OR MORE/ INCHES OF HEAVY WET SNOW ACROSS THE LAURELS. IT APPEARS AT THIS TIME WE/RE LEANING TWD WINTER WEATHER ADVISORY TYPE AMTS FOR LATE TONIGHT THROUGH EARLY SUNDAY AFTERNOON. THE DAYTIME /AND LATE MARCH SUN ANGLE/ ON SUNDAY SHOULD HELP TEMPS RISE SLIGHTLY...BUT THE UPPER LOW/TROUGH AXIS WILL BE RIGHT OVERHEAD. CLOUDS WILL BE THICK EVEN WHERE THE PRECIP GETS LIGHTER/SPOTTY. IT WONT FEEL TOO NICE WITH TEMPS IN THE 30S NW AND L-M40S ELSEWHERE. THE WIND WILL GET CRANKING WITH THE DEEPENING SFC LOW VERY CLOSE BY. HAVE NUDGED POPS UP FOR SUNDAY AND EARLY SUNDAY NIGHT TO ALLOW FOR THE FURTHER SLOW-DOWN IN THE CONSENSUS OF MDL DATA. && .LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/... LATEST MODEL SOLUTIONS CONTINUE TO SLOW DOWN THE PROGRESSION OF THIS WEEKEND/S STORM...RESULTING IN LINGERING SHOWERS OVER THE EAST FOR SUNDAY. TEMPERATURES WILL BE COLD ENOUGH SATURDAY NIGHT AND INTO THE MORNING HOURS ON SUNDAY FOR THE PRECIPITATION TO FALL AS A LIGHT DUSTING OF SNOW OVER THE NORTH AND HIGHER ELEVATIONS. AT THIS POINT...MONDAY WILL BE ONE OF THE BEST DAYS OF THE EXTENDED FORECAST WITH HIGH PRESSURE...FAIR SKIES...AND SEASONABLE TEMPERATURES. A LOW PRESSURE SYSTEM WILL SLIDE NORTH OF THE STATE TUESDAY NIGHT...BRINGING MORE CLOUDS TO THE REGION. LIGHT SHOWERS CANNOT BE RULED OUT ACROSS THE NORTH AS A WEAK COLD FRONT MOVES THROUGH. SUNSHINE WILL MAKE A BRIEF RETURN FOR WEDNESDAY BEFORE ANOTHER STORM SYSTEM ORGANIZES OVER THE MIDWEST...AND MOVE EAST FOR THE END OF THE WEEK. THERE IS STILL A GOOD BIT OF MODEL SPREAD...BUT RAIN SHOWERS ARE POSSIBLE AS EARLY AS THURSDAY AS THE ASSOCIATED WARM FRONT NOSES INTO PENNSYLVANIA. THE COLD FRONT WILL MOVE THROUGH THE AREA DURING THE FIRST PART OF THE WEEKEND BRINGING MORE RAIN. && .AVIATION /18Z SATURDAY THROUGH THURSDAY/... MVFR TO VFR STRATO CU AND AREAS OF ALTO CU ACROSS THE NRN HALF OF PENN WILL GRADUALLY LOWER LATER TODAY AND TONIGHT...TO MAINLY IFR WITH POCKETS OF LIFR AS RAIN OVERSPREADS THE AREA FROM THE SOUTH...AND CHANGES FROM FZRA TO SLEET...THEN SNOW INVOF KBFD AND POINTS WEST AFTER 00Z SUNDAY. IFR ACROSS THE SOUTH EARLY THIS AFTERNOON WILL STAY INTACT THROUGH SUNDAY MORNING...WITH PERIODS OF LIFR LIKELY IN FOG /AND EVENTUALLY MIXED PRECIP CHANGING TO SNOW ACROSS THE LAURELS/. DEVELOPING LOW PRESSURE OVR THE SE STATES WILL LIFT UP THE APPALACHIAN MTNS LATER TODAY...HELPING TO SPREAD RAIN AND LOWERING CIGS NORTHWARD ACROSS PENNSYLVANIA. UNSTABLE AIR WORKING INTO SE PA WILL BRING A LOW PROBABILITY FOR A A FEW TSRA ARND KMDT AND KLNS THIS EVENING. OUTLOOK... SUN...WINDY. RAIN/LOW CIGS POSS...ESP EAST. MON-WED...NO SIG WX EXPECTED. && .HYDROLOGY... FLOOD WATCH CONTINUES FOR ABOUT EASTERN THIRD OF CWA FOR LATER TODAY THROUGH SUNDAY EVENING. THE UPPER LOW IS EXPECTED TO CLOSE OFF AND POSSIBLY STALL ALONG MID ATLC COAST. THIS WILL PRODUCE MDT TO HEAVY RAINS OVER MUCH OF THE AREA DURING THIS PD. THE HIGHER AMOUNTS STILL LOOK TO BE IN THE EAST...ESPECIALLY IF A WIDELY PROGGED DEFORMATION-TYPE AREA OF PRECIP FORMS ON SUNDAY. LOCALIZED STORM TOTAL AMOUNTS OF 1-2 INCHES SEEM REASONABLE. BUT IF IT CONTINUES TO LOOK LIKE THE PRECIP WILL RE-INVIGORATE ON SUNDAY...THE WATCH MAY NEED TO BE EXTENDED. GEFS/SREF GUIDANCE SHOWS PWAT ANOMALIES GREATER THAN 2 STANDARD DEVIATES OVER EASTERN PA SAT AFTN AND EVENING PROVIDING SUFFICIENT MOISTURE FOR HIGH RAINFALL RATES. && .CTP WATCHES/WARNINGS/ADVISORIES... FLOOD WATCH THROUGH SUNDAY EVENING FOR PAZ028-036-037-041-042- 046-049>053-056>059-063>066. WINTER WEATHER ADVISORY FROM 8 PM THIS EVENING TO NOON EDT SUNDAY FOR PAZ004>006. && $$ SYNOPSIS...LAMBERT/DANGELO NEAR TERM...LAMBERT SHORT TERM...DANGELO LONG TERM...COLBERT AVIATION...LAMBERT HYDROLOGY...LAMBERT
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
943 AM EDT SAT MAR 29 2014 .SYNOPSIS... A WAVE OF LOW PRESSURE WILL FORM OVER KENTUCKY AND TENNESSEE AND MOVE TO THE DELMARVA REGION BY TONIGHT. THE ASSOCIATED UPPER LEVEL TROUGH WILL GET DEEPER...SLOWING DOWN THE SYSTEM SIGNIFICANTLY. MILDER TEMPERATURES BUT CONTINUED UNSETTLED CONDITIONS ARE EXPECTED FOR NEXT WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... THE NW EDGE OF A LARGE SHIELD OF STEADY LIGHT TO MODERATE RAIN CONTINUES TO DRIFT NORTH AND IS ENTERING FAR SERN YORK COUNTY AND SERN LANCASTER COUNTY AT 13Z. THIS WILL BE A LONG-DURATION PRECIP EVENT FOR MOST OF THE CWA...LASTING BETWEEN 36-48 HOURS. THE BULK OF THE PRECIP WILL FALL AS RAIN OF VARYING INTENSITY...BUT LATER SECTIONS OF THIS DISCUSSION WILL COVER THE WINTRY ASPECTS OF THIS SLOW-MOVING WEATHER SYSTEM /EXPECTED TO IMPACT THE HIGHER TERRAIN OF THE NORTH AND WEST AS WE PROGRESS LATER INTO THE WEEKEND. FOR THE NEAR TERM...POCKETS OF SUNSHINE THROUGH THIN CIRRUS JUST NORTH OF THE I-80 CORRIDOR /AND SANDWICHED BETWEEN LOWER STRATUS/STRATOCU AND NS CLOUDS TO THE SOUTH AND NORTH/ WILL VANISH DURING THE MIDDAY HOURS AS THICKER...LAYERED CLOUDS SPREAD IN FROM THE SOUTH. 12Z 13KM RAP AND 09Z SREF INDICATE THAT MUCH OF CENTRAL AND NRN PENN WILL STAY DRY UNDER MAINLY A MID CLOUD DECK THROUGH 18-20Z BEFORE THE RAIN ENCROACHES FROM THE SW AND SE. PRACTICALLY ALL LOCATIONS IN THE CWA SHOULD SEE RAIN BY 23Z TODAY...WITH THE HIGHEST TOTALS /BETWEEN 0.25-0.50 OF AN INCH/ OCCURRING ACROSS THE LAURELS...AND FAR SERN COUNTIES. TEMPS REMAIN IN THE 30S FOR A LARGE PORTION OF THE AREA LATE THIS MORNING /AFTER EXTENDED PERIODS OF CLEAR TO PARTLY CLOUDY SKIES OVERNIGHT/... BUT ARE IN THE 40S TO NEAR 50F ACROSS THE LOWER SUSQ VALLEY WHERE CLOUD COVER ADVANCED INTO THAT REGION MUCH EARLIER. AS THE CLOUDS THICKEN AND RAIN GRADUALLY OVERSPREADS THE AREA THIS AFTERNOON...TEMPS WILL SLOW THEIR CLIMB AND LEVEL OFF. HIGHS WILL VARY FROM THE U30S IN THE NW...TO AROUND 50F IN THE SE. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/... THE STORM DEEPENS RAPIDLY AS IT MOVES OVER THE MID-ATLANTIC STATES. THE UPPER LEVEL TROUGH CUTS OFF AND THE WIND PULLS IN LOTS OF MOISTURE...MAINLY FROM THE SOUTH/GOMEX. BUT THE SYSTEM ALMOST STALLS OVERHEAD. THIS WILL CREATE HEAVY RAIN FOR MUCH OF THE AREA...BUT MAINLY OVER THE EAST WHERE FLOOD WATCH IS ALREADY IN EFFECT. SEE HYDRO SECTION FOR MORE ON WATER ISSUES. THE OTHER TROUBLE WITH THE PRECIP IS THAT THE TEMPS DO DROP IN THE EVENING AND ESPECIALLY OVERNIGHT. THUS...THE NORTHWESTERN COUNTIES AND HIGHER ELEVATION IN THE CENTRAL MTNS WILL LIKELY SEE THE RAIN TURN TO SNOW AS THE NIGHT CONTINUES. SOME INDICATIONS OF FREEZING RAIN...WITH TEMPS COOLING BELOW FREEZING BEFORE THE ENTIRE COLUMN COOLS. THUS...HAVE MENTIONED CHC ZR IN THE GRIDS FOR THE SECOND HALF OF THE NIGHT ALONG WITH THE TURN OVER TO SNOW - WHICH IS MORE LIKELY TO OCCUR. TEMPS DO NOT SEEM TO EVER GET AOB FZG IN THE RIDGE AND VALLEY REGION SO...WILL JUST GO WITH A GRADUAL CHANGE/MIX HERE. QPF IN THE NORTHWEST AFTER THE CHANGE TO SNOW IS A VERY DIFFICULT PART OF THE FCST. IN GENERAL...THE EXPECTATION IS THAT THE HEAVY PRECIP WILL BE TO THE EAST BY THE MIDDLE OF THE NIGHT...AND SNOW ACCUMS SHOULD BE AN INCH OR TWO IN THE FAR NWRN COS...BUT IF IT TURNS MORE-QUICKLY...3-4 INCHES IS POSSIBLE. BUT...WILL KEEP THE FCST CONSERVATIVE AT THIS POINT. THE DAYTIME ON SUNDAY SHOULD HELP TEMPS RISE SLIGHTLY...BUT THE UPPER LOW/TROUGH AXIS WILL BE RIGHT OVERHEAD. CLOUDS WILL BE THICK EVEN WHERE THE PRECIP GETS LIGHTER/SPOTTY. IT WONT FEEL TOO NICE WITH TEMPS IN THE 30S NW AND L-M40S ELSEWHERE. THE WIND WILL GET CRANKING WITH THE DEEPENING SFC LOW VERY CLOSE BY. HAVE NUDGED POPS UP FOR SUNDAY AND EARLY SUNDAY NIGHT TO ALLOW FOR THE FURTHER SLOW-DOWN IN THE CONSENSUS OF MDL DATA. && .LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/... LATEST MODEL SOLUTIONS CONTINUE TO SLOW DOWN THE PROGRESSION OF THIS WEEKEND/S STORM...RESULTING IN LINGERING SHOWERS OVER THE EAST FOR SUNDAY. TEMPERATURES WILL BE COLD ENOUGH SATURDAY NIGHT AND INTO THE MORNING HOURS ON SUNDAY FOR THE PRECIPITATION TO FALL AS A LIGHT DUSTING OF SNOW OVER THE NORTH AND HIGHER ELEVATIONS. AT THIS POINT...MONDAY WILL BE ONE OF THE BEST DAYS OF THE EXTENDED FORECAST WITH HIGH PRESSURE...FAIR SKIES...AND SEASONABLE TEMPERATURES. A LOW PRESSURE SYSTEM WILL SLIDE NORTH OF THE STATE TUESDAY NIGHT...BRINGING MORE CLOUDS TO THE REGION. LIGHT SHOWERS CANNOT BE RULED OUT ACROSS THE NORTH AS A WEAK COLD FRONT MOVES THROUGH. SUNSHINE WILL MAKE A BRIEF RETURN FOR WEDNESDAY BEFORE ANOTHER STORM SYSTEM ORGANIZES OVER THE MIDWEST...AND MOVE EAST FOR THE END OF THE WEEK. THERE IS STILL A GOOD BIT OF MODEL SPREAD...BUT RAIN SHOWERS ARE POSSIBLE AS EARLY AS THURSDAY AS THE ASSOCIATED WARM FRONT NOSES INTO PENNSYLVANIA. THE COLD FRONT WILL MOVE THROUGH THE AREA DURING THE FIRST PART OF THE WEEKEND BRINGING MORE RAIN. && .AVIATION /13Z SATURDAY THROUGH WEDNESDAY/... MAIN AVIATION CONCERN EARLY THIS MORNING WILL BE LOW CIGS ACROSS THE N MTNS...THE RESULT OF RESIDUAL LOW LVL MOISTURE TRAPPED BENEATH INVERSION AND FORCED TO ASCEND THE HIGH TERRAIN OF NORTHERN PA. KBFD CONTINUES TO REPORT A CIG OF JUST 200FT AT 13Z...AND THIS SHOULD PERSIST FOR AT LEAST THE NEXT HOUR OR SO...YIELDING TO AN IFR TO MVFR DECK OF STRATO CU THIS AFTERNOON. ELSEWHERE...MVFR STRATO CU WERE NOTED ACRS THE LOWER SUSQ VALLEY /INCLUDING KMDT......KCXY...KTHV AND KLNS/ WITH VFR BKN-OVC ALTOCU ELSEWHERE. LITTLE CHANGE IN THESE CONDITIONS ARE EXPECTED THROUGH THIS AFTERNOON. DEVELOPING LOW PRESSURE OVR THE SE STATES WILL LIFT UP THE APPALACHIAN MTNS LATER TODAY...HELPING TO SPREAD RAIN AND LOWERING CIGS NORTHWARD ACROSS PENNSYLVANIA. EXPECT WIDESPREAD IFR/LIFR CONDS IN RAIN/LOW CIGS LATE THIS AFTN AND EVENING...AS THE STORM SYSTEM APPROACHES PA. COLDER AIR WRAPPING INTO THIS SYSTEM COULD CHANGE RAIN TO MIXED PRECIP AT KBFD LATE THIS EVENING...WHILE UNSTABLE AIR WORKING INTO SE PA COULD POTENTIALLY SPAWN A FEW TSRA ARND KMDT AND KLNS THIS EVENING. OUTLOOK... SUN...WINDY. RAIN/LOW CIGS POSS...ESP EAST. MON-WED...NO SIG WX EXPECTED. && .HYDROLOGY... FLOOD WATCH CONTINUES FOR ABOUT EASTERN THIRD OF CWA FOR LATER TODAY THROUGH SUNDAY NIGHT. THE UPPER LOW IS EXPECTED TO CLOSE OFF AND POSSIBLY STALL ALONG MID ATLC COAST. THIS WILL PRODUCE MDT TO HEAVY RAINS OVER MUCH OF THE AREA DURING THIS PD. THE HIGHER AMOUNTS STILL LOOK TO BE IN THE EAST...ESPECIALLY IF A WIDELY PROGGED DEFORMATION-TYPE AREA OF PRECIP FORMS ON SUNDAY. LOCALIZED STORM TOTAL AMOUNTS OF 1-2 INCHES SEEM REASONABLE. BUT IF IT CONTINUES TO LOOK LIKE THE PRECIP WILL RE-INVIGORATE ON SUNDAY...THE WATCH MAY NEED TO BE EXTENDED. GEFS/SREF GUIDANCE SHOWS PWAT ANOMALIES GREATER THAN 2 STANDARD DEVIATES OVER EASTERN PA SAT AFTN AND EVENING PROVIDING SUFFICIENT MOISTURE FOR HIGH RAINFALL RATES. && .CTP WATCHES/WARNINGS/ADVISORIES... FLOOD WATCH THROUGH SUNDAY EVENING FOR PAZ028-036-037-041-042- 046-049>053-056>059-063>066. && $$ SYNOPSIS...LAMBERT/DANGELO NEAR TERM...LAMBERT SHORT TERM...DANGELO LONG TERM...COLBERT AVIATION...LAMBERT/FITZGERALD HYDROLOGY...LAMBERT/DANGELO
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
104 PM CDT SAT MAR 29 2014 .UPDATE...FOR 18Z TAFS. && .AVIATION... SFC LOW/COLD FRONT NOW WELL EAST OF THE MID-STATE BUT PLENTY OF LL MOISTURE/SHOWERS REMAIN BEHIND. HEAVIER RAIN OVER FOR CKV/BNA BUT STILL MAY AFFECT CSV THROUGH 21Z OR SO. MOISTURE EXTENDS WELL UPSTREAM AND THAT IS LIKELY TO KEEP AT LEAST MVFR CIGS ACROSS THE AREA WELL INTO THE EVENING AND POSSIBLY INTO THE OVERNIGHT CSV. WINDS GUSTING 20-25KTS EXPECTED TO KEEP VSBYS FAVORABLE BUT FOG MAY REDEVELOP OVERNIGHT AS WIND WEAKENS. && .PREV DISCUSSION... /ISSUED 1112 AM CDT SAT MAR 29 2014/ UPDATE... SFC LOW CURRENTLY CENTERED ACROSS EAST TN/NORTH GA...WITH TRAILING UPPER TROUGH NEAR THE MS RIVER. WIDESPREAD RAIN CONTINUES ACROSS THE MID-STATE BUT THE BACK EDGE IS NOT FAR WEST OF THE TN RIVER. NORTHWEST WINDS BEHIND PULLING DOWN MUCH COOLER AIR WITH TEMPS UPSTREAM LARGELY MID 40S. DO EXPECT RAIN TO PULL EAST THIS AFTERNOON BUT DO NOT EXPECT MUCH RECOVERY IN TEMPS...ESPECIALLY WITH A LOW CLOUD DECK LIKELY MOST OF THE DAY. WILL LOWER TEMPS AND REALIGN AFTERNOON WX SLIGHTLY. PREV DISCUSSION... /ISSUED 600 AM CDT SAT MAR 29 2014/ UPDATE... 12Z TAF DISCUSSION. AVIATION... -SHRA WILL CONTINUE SPREADING ACROSS AREA AIRPORTS THIS MORNING BEFORE EXITING CKV/BNA BY EARLY AFTERNOON AND CSV BY EVENING. LITTLE LIGHTNING HAS BEEN NOTED AND WILL LEAVE OUT MENTION OF TS. MVFR/IFR CIGS TO BECOME VFR LATE IN THE TAF PERIOD AT CKV/BNA...BUT THESE CIGS MAY LINGER AT CSV. LIGHT SOUTHEAST/NORTHEAST WINDS WILL BECOME NORTHWEST AND GUSTY BY AFTERNOON AS COLD FRONT MOVES ACROSS. SHAMBURGER PREV DISCUSSION... /ISSUED 335 AM CDT SAT MAR 29 2014/ DISCUSSION... SFC LOW WL MOVE FROM EASTERN MS ACRS E TN TDY. INVERTED TROF OVER THE MID STATE WILL ALSO SHIFT EAST AND ALLOW COLDER AIR TO FILTER IN. THE MAIN CHALLENGES IN THE NEAR TERM INVOLVE PCPN CVRG AND HOW MUCH TEMPS WL RECOVER AS PCPN PULLS OUT LATER. FOR NOW LEANED PCPN FCST TWRD THE LATEST HRRR WHICH HAS HAD A PRETTY GOOD HANDLE ON THINGS THUS FAR. XPCT TO SEE RAIN INCRS IN CVRG QUICKLY OVER THE NEXT FEW HOURS AND GRADUALLY EVOLVE INTO A BIT OF A COMMA HEAD BEFORE PULLING OUT LATER THIS AFTN. RAIN WILL LIKELY NOT REACH THE PLATEAU UNTIL MID MORNING AND WILL BE ENDING ALONG THE TN RIVER BY MIDDAY. AS FAR AS TEMPS GO...HIGHS ARND NASHVILLE AND POINTS EAST WILL LIKELY BE RIGHT ARND 8 AM JUST AHEAD OF THE BNDRY WITH A PRETTY SHARP DROP THRU THE MORNING. WILL SEE SOME TEMPERATURE RECOVERY AGAIN IN THE AFTN AS RAIN CVRG DECREASES. SOME RAIN MAY LINGER IN THE FAR EAST ERLY THIS EVE OTHW XPCT A QUICK CLEARING AS SYS PULLS AWAY. MAV TEMPERATURES LOOK RSNBL GIVEN THE CLEARING SKIES AND A PRETTY COOL START. WX THEN LOOKS NICE AND SPRINGLIKE INTO MID-WEEK AS RIDGING DOMINATES. STILL WL HV TO WATCH WEAK FRONT ON TUE FOR SOME CLDS AND A LITTLE LIGHT PCPN BUT DOESN`T LOOK LIKE MUCH RIGHT NOW. HPC TEMPS WERE FOLLOWED PRETTY CLOSE. THE FAR EXTENDED STILL LOOKS ACTIVE BUT AS IS TYPICAL THE ALL IMPORTANT DETAILS ARE MURKY. GENERAL PATTERN SUGGESTS WARM AND HUMID CONDITIONS WITH ROUNDS OF SHOWERS AND STORMS AS SFC LOWS MOVE TO OUR WEST. && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 07
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
1112 AM CDT SAT MAR 29 2014 .UPDATE... SFC LOW CURRENTLY CENTERED ACROSS EAST TN/NORTH GA...WITH TRAILING UPPER TROUGH NEAR THE MS RIVER. WIDESPREAD RAIN CONTINUES ACROSS THE MID-STATE BUT THE BACK EDGE IS NOT FAR WEST OF THE TN RIVER. NORTHWEST WINDS BEHIND PULLING DOWN MUCH COOLER AIR WITH TEMPS UPSTREAM LARGELY MID 40S. DO EXPECT RAIN TO PULL EAST THIS AFTERNOON BUT DO NOT EXPECT MUCH RECOVERY IN TEMPS...ESPECIALLY WITH A LOW CLOUD DECK LIKELY MOST OF THE DAY. WILL LOWER TEMPS AND REALIGN AFTERNOON WX SLIGHTLY. && .PREV DISCUSSION... /ISSUED 600 AM CDT SAT MAR 29 2014/ UPDATE... 12Z TAF DISCUSSION. AVIATION... -SHRA WILL CONTINUE SPREADING ACROSS AREA AIRPORTS THIS MORNING BEFORE EXITING CKV/BNA BY EARLY AFTERNOON AND CSV BY EVENING. LITTLE LIGHTNING HAS BEEN NOTED AND WILL LEAVE OUT MENTION OF TS. MVFR/IFR CIGS TO BECOME VFR LATE IN THE TAF PERIOD AT CKV/BNA...BUT THESE CIGS MAY LINGER AT CSV. LIGHT SOUTHEAST/NORTHEAST WINDS WILL BECOME NORTHWEST AND GUSTY BY AFTERNOON AS COLD FRONT MOVES ACROSS. SHAMBURGER PREV DISCUSSION... /ISSUED 335 AM CDT SAT MAR 29 2014/ DISCUSSION... SFC LOW WL MOVE FROM EASTERN MS ACRS E TN TDY. INVERTED TROF OVER THE MID STATE WILL ALSO SHIFT EAST AND ALLOW COLDER AIR TO FILTER IN. THE MAIN CHALLENGES IN THE NEAR TERM INVOLVE PCPN CVRG AND HOW MUCH TEMPS WL RECOVER AS PCPN PULLS OUT LATER. FOR NOW LEANED PCPN FCST TWRD THE LATEST HRRR WHICH HAS HAD A PRETTY GOOD HANDLE ON THINGS THUS FAR. XPCT TO SEE RAIN INCRS IN CVRG QUICKLY OVER THE NEXT FEW HOURS AND GRADUALLY EVOLVE INTO A BIT OF A COMMA HEAD BEFORE PULLING OUT LATER THIS AFTN. RAIN WILL LIKELY NOT REACH THE PLATEAU UNTIL MID MORNING AND WILL BE ENDING ALONG THE TN RIVER BY MIDDAY. AS FAR AS TEMPS GO...HIGHS ARND NASHVILLE AND POINTS EAST WILL LIKELY BE RIGHT ARND 8 AM JUST AHEAD OF THE BNDRY WITH A PRETTY SHARP DROP THRU THE MORNING. WILL SEE SOME TEMPERATURE RECOVERY AGAIN IN THE AFTN AS RAIN CVRG DECREASES. SOME RAIN MAY LINGER IN THE FAR EAST ERLY THIS EVE OTHW XPCT A QUICK CLEARING AS SYS PULLS AWAY. MAV TEMPERATURES LOOK RSNBL GIVEN THE CLEARING SKIES AND A PRETTY COOL START. WX THEN LOOKS NICE AND SPRINGLIKE INTO MID-WEEK AS RIDGING DOMINATES. STILL WL HV TO WATCH WEAK FRONT ON TUE FOR SOME CLDS AND A LITTLE LIGHT PCPN BUT DOESN`T LOOK LIKE MUCH RIGHT NOW. HPC TEMPS WERE FOLLOWED PRETTY CLOSE. THE FAR EXTENDED STILL LOOKS ACTIVE BUT AS IS TYPICAL THE ALL IMPORTANT DETAILS ARE MURKY. GENERAL PATTERN SUGGESTS WARM AND HUMID CONDITIONS WITH ROUNDS OF SHOWERS AND STORMS AS SFC LOWS MOVE TO OUR WEST. && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 07
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
600 AM CDT SAT MAR 29 2014 .UPDATE... 12Z TAF DISCUSSION. && .AVIATION... -SHRA WILL CONTINUE SPREADING ACROSS AREA AIRPORTS THIS MORNING BEFORE EXITING CKV/BNA BY EARLY AFTERNOON AND CSV BY EVENING. LITTLE LIGHTNING HAS BEEN NOTED AND WILL LEAVE OUT MENTION OF TS. MVFR/IFR CIGS TO BECOME VFR LATE IN THE TAF PERIOD AT CKV/BNA...BUT THESE CIGS MAY LINGER AT CSV. LIGHT SOUTHEAST/NORTHEAST WINDS WILL BECOME NORTHWEST AND GUSTY BY AFTERNOON AS COLD FRONT MOVES ACROSS. SHAMBURGER && .PREV DISCUSSION... /ISSUED 335 AM CDT SAT MAR 29 2014/ DISCUSSION... SFC LOW WL MOVE FROM EASTERN MS ACRS E TN TDY. INVERTED TROF OVER THE MID STATE WILL ALSO SHIFT EAST AND ALLOW COLDER AIR TO FILTER IN. THE MAIN CHALLENGES IN THE NEAR TERM INVOLVE PCPN CVRG AND HOW MUCH TEMPS WL RECOVER AS PCPN PULLS OUT LATER. FOR NOW LEANED PCPN FCST TWRD THE LATEST HRRR WHICH HAS HAD A PRETTY GOOD HANDLE ON THINGS THUS FAR. XPCT TO SEE RAIN INCRS IN CVRG QUICKLY OVER THE NEXT FEW HOURS AND GRADUALLY EVOLVE INTO A BIT OF A COMMA HEAD BEFORE PULLING OUT LATER THIS AFTN. RAIN WILL LIKELY NOT REACH THE PLATEAU UNTIL MID MORNING AND WILL BE ENDING ALONG THE TN RIVER BY MIDDAY. AS FAR AS TEMPS GO...HIGHS ARND NASHVILLE AND POINTS EAST WILL LIKELY BE RIGHT ARND 8 AM JUST AHEAD OF THE BNDRY WITH A PRETTY SHARP DROP THRU THE MORNING. WILL SEE SOME TEMPERATURE RECOVERY AGAIN IN THE AFTN AS RAIN CVRG DECREASES. SOME RAIN MAY LINGER IN THE FAR EAST ERLY THIS EVE OTHW XPCT A QUICK CLEARING AS SYS PULLS AWAY. MAV TEMPERATURES LOOK RSNBL GIVEN THE CLEARING SKIES AND A PRETTY COOL START. WX THEN LOOKS NICE AND SPRINGLIKE INTO MID-WEEK AS RIDGING DOMINATES. STILL WL HV TO WATCH WEAK FRONT ON TUE FOR SOME CLDS AND A LITTLE LIGHT PCPN BUT DOESN`T LOOK LIKE MUCH RIGHT NOW. HPC TEMPS WERE FOLLOWED PRETTY CLOSE. THE FAR EXTENDED STILL LOOKS ACTIVE BUT AS IS TYPICAL THE ALL IMPORTANT DETAILS ARE MURKY. GENERAL PATTERN SUGGESTS WARM AND HUMID CONDITIONS WITH ROUNDS OF SHOWERS AND STORMS AS SFC LOWS MOVE TO OUR WEST. && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 55
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
335 AM CDT SAT MAR 29 2014 .DISCUSSION... SFC LOW WL MOVE FROM EASTERN MS ACRS E TN TDY. INVERTED TROF OVER THE MID STATE WILL ALSO SHIFT EAST AND ALLOW COLDER AIR TO FILTER IN. THE MAIN CHALLENGES IN THE NEAR TERM INVOLVE PCPN CVRG AND HOW MUCH TEMPS WL RECOVER AS PCPN PULLS OUT LATER. FOR NOW LEANED PCPN FCST TWRD THE LATEST HRRR WHICH HAS HAD A PRETTY GOOD HANDLE ON THINGS THUS FAR. XPCT TO SEE RAIN INCRS IN CVRG QUICKLY OVER THE NEXT FEW HOURS AND GRADUALLY EVOLVE INTO A BIT OF A COMMA HEAD BEFORE PULLING OUT LATER THIS AFTN. RAIN WILL LIKELY NOT REACH THE PLATEAU UNTIL MID MORNING AND WILL BE ENDING ALONG THE TN RIVER BY MIDDAY. AS FAR AS TEMPS GO...HIGHS ARND NASHVILLE AND POINTS EAST WILL LIKELY BE RIGHT ARND 8 AM JUST AHEAD OF THE BNDRY WITH A PRETTY SHARP DROP THRU THE MORNING. WILL SEE SOME TEMPERATURE RECOVERY AGAIN IN THE AFTN AS RAIN CVRG DECREASES. SOME RAIN MAY LINGER IN THE FAR EAST ERLY THIS EVE OTHW XPCT A QUICK CLEARING AS SYS PULLS AWAY. MAV TEMPERATURES LOOK RSNBL GIVEN THE CLEARING SKIES AND A PRETTY COOL START. WX THEN LOOKS NICE AND SPRINGLIKE INTO MID-WEEK AS RIDGING DOMINATES. STILL WL HV TO WATCH WEAK FRONT ON TUE FOR SOME CLDS AND A LITTLE LIGHT PCPN BUT DOESN`T LOOK LIKE MUCH RIGHT NOW. HPC TEMPS WERE FOLLOWED PRETTY CLOSE. THE FAR EXTENDED STILL LOOKS ACTIVE BUT AS IS TYPICAL THE ALL IMPORTANT DETAILS ARE MURKY. GENERAL PATTERN SUGGESTS WARM AND HUMID CONDITIONS WITH ROUNDS OF SHOWERS AND STORMS AS SFC LOWS MOVE TO OUR WEST. && .PRELIMINARY POINT TEMPS/POPS... NASHVILLE 57 34 61 38 / 90 0 0 0 CLARKSVILLE 54 31 59 38 / 90 0 0 05 CROSSVILLE 56 35 54 33 / 90 20 0 05 COLUMBIA 59 35 63 38 / 90 0 0 05 LAWRENCEBURG 60 35 63 36 / 90 0 0 05 WAVERLY 57 33 61 39 / 90 0 0 05 && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ JOHNSTONE
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
425 PM EDT SAT MAR 29 2014 .SYNOPSIS... A LOW PRESSURE PASSING WEST OF THE REGION THIS AFTERNOON WILL DRAG A COLD FRONT ACROSS THE MID ATLANTIC DURING THE EVENING. THE SUPPORTING UPPER LEVEL LOW WILL PASS ACROSS THE CENTRAL APPALACHIANS OVERNIGHT...RESULTING IN UPSLOPE SNOW SHOWERS AND VERY STRONG WINDS LATE TONIGHT THROUGH SUNDAY EVENING. HIGH PRESSURE WILL RETURN TO THE AREA SUNDAY NIGHT AND MONDAY. && .NEAR TERM /THROUGH SUNDAY/... AS OF 400 PM EDT SATURDAY... EXPECT A VERY ACTIVE AND CHALLENGING WEATHER FORECAST FOR THE NEXT 24 HOURS. CURRENTLY KEEPING AN EYE ON A SURFACE LOW PRESSURE SYSTEM PASSING NORTHEAST ACROSS EXTREME WESTERN VIRGINIA THIS AFTERNOON. DEEP ATLANTIC MOISTURE FLOWING INTO OUR REGION HAS MAINTAINED SHOWERY AND FOGGY CONDITIONS ACROSS MOST OF THE AREA THROUGH THE DAY...AND EXPECT THESE CONDITIONS TO PERSIST THROUGH THE EVENING UNTIL THE COLD FRONT ARRIVES. THE COLD FRONT IS EXPECTED TO ENTER OUR WESTERN COUNTIES BY AROUND 6 PM...TRIGGERING A BROKEN LINE OF SHOWERS AS IT PASSES. THE FRONT WILL THEN SHIFT EAST...EXITING OUR AREA TO THE EAST RIGHT AROUND MIDNIGHT. THE FOGGY SHOWERY CONDITIONS HAVE DONE A GOOD JOB OF LIMITING INSTABILITY THIS AFTERNOON...SUCH THAT THE THREAT OF ANY STRONG THUNDERSTORM DEVELOPMENT APPEARS STRICTLY LIMITED THIS AFTERNOON. BEST CHANCES FOR THUNDERSTORM ACTIVITY REMAIN ACROSS PORTIONS OF THE NORTH CAROLINA PIEDMONT AND SOUTHSIDE VIRGINIA THIS EVENING...POSSIBLY RESULTING IN PERIODS OF HEAVY RAIN AND ISOLATED GUSTY WINDS. AS THE FRONT EXITS THE AREA...WE TURN OUR ATTENTION TO THE PASSAGE OF THE SUPPORTING UPPER LEVEL LOW PRESSURE SYSTEM THAT WILL PASS ACROSS THE SOUTHERN HALF OF OUR AREA AFTER MIDNIGHT. THE FIRST CONCERN WILL BE THE UPSLOPE SNOW SHOWERS THAT WILL DEVELOP ACROSS THE MOUNTAINS. MODELS CONTINUE TO INDICATE A STRONG DEFORMATION ZONE DEVELOPING ACROSS CENTRAL WEST VIRGINIA OVERNIGHT WHICH WILL ENHANCE THE SNOW SHOWERS ACROSS OUR WESTERN RIDGES. BELIEVE WE WILL SEE A FEW HOURS OF HEAVY SNOW BETWEEN MIDNIGHT AND SUNRISE SUCH THAT WE CAN EXPECT 4 TO 6 INCHES ABOVE 2500 FEET IN GREENBRIER...SUMMERS AND MERCER COUNTIES IN SOUTHEAST WEST VIRGINIA...AND 1 TO 4 INCHES ELSEWHERE ACROSS MOST OF OUR REMAINING MOUNTAIN COUNTIES UP TO THE BLUE RIDGE. SNOW SHOWERS WILL DIMINISH BY LATE SUNDAY MORNING AS THE UPPER LOW SHIFTS AWAY FROM OUR AREA. THE OTHER CONCERN WILL BE STRONG WINDS BEGINNING TONIGHT. A QUICK SURGE IN WINDS RIGHT BEHIND THE FRONT WILL CAUSE SPEEDS TO RAPIDLY INCREASE FROM SOUTHWEST TO NORTHEAST...AND REACH ADVISORY/WARNING CRITERIA OVER PARTS OF THE MOUNTAINS DURING THE EARLY MORNING HOURS AS THE PROGGED 85H JET TOPS 50 KTS AND MUCH COLDER AIR RUSHES IN. FORECAST INVERSION REMAINS RELATIVELY HIGH BUT GIVEN LATE NIGHT TIMING WOULD FAVOR GOING ON THE STRONG SIDE OF GUIDANCE DESPITE SOME OFFSET IN MIXING VIA CLOUDS INTO EARLY SUNDAY MORNING. MIXING ALONG/EAST OF THE BLUE RIDGE BECOMES DEEPEST SUNDAY MORNING INTO SUNDAY AFTERNOON WHEN A VERY IMPRESSIVE JET COUPLET ALOFT SLIDES ACROSS AND SUBSIDENCE MAXES OVERHEAD. GRADIENT LOOKS QUITE TIGHT AND IF CLOUDS CLEAR QUICKER THEN SPEEDS MAY BE STRONGER...ESPECIALLY EAST OF THE BLUE RIDGE SUNDAY AFTERNOON AS PERHAPS GRAVITY WAVES SLIDE OFF THE MOUNTAINS. SINCE THE CORE OF THE STRONGER WINDS LIKELY TO IMPACT AREAS FROM THE ROANOKE VALLEY INTO THE NORTHWEST NORTH CAROLINA MOUNTAINS WHERE DAMAGING WINDS MORE LIKELY...HAVE UPGRADED PARTS OF THE GOING ADVISORY TO A HIGH WIND WARNING AND INCLUDED THE VA HIGHLANDS FOR MAINLY HIGHER ELEVATION SPEEDS. INCLUDED AN ADVISORY ELSW OVER THE EARLIER WATCH AREA AS WELL AS ADDING HENRY...MERCER AND MONROE COUNTIES FOR NOW GIVEN POTENTIAL TREE DAMAGE PER WET SOILS. CONDITIONS WILL IMPROVE DURING LATE AFTERNOON AND EVENING AS THE UPPER SYSTEM PUSHES AWAY FROM THE AREA...WITH WIND SPEEDS DIMINISHING AND SNOW SHOWERS COMING TO AN END. && .SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/... AS OF 215 PM EDT SATURDAY... DEEP LOW PRESSURE WILL BE SLOWLY EXITING OFFSHORE SUNDAY NIGHT ALLOWING DRIER HIGH PRESSURE TO BUILD IN FROM THE WEST. HOWEVER WITH THIS LOW BASICALLY CUTOFF...THE GRADIENT BETWEEN THE TWO WILL BE SLOW TO WEAKEN WITH STRONG WINDS LIKELY TO CONTINUE INTO SUNDAY EVENING PROVIDING FOR ONLY A GRADUAL DIMINISHING TREND BY EARLY MONDAY. THINK RESIDUAL DEEPER MOISTURE SHOULD BE EAST OF THE AREA BY SUNDAY NIGHT SO GOING WITH CLEARING SKIES WITHOUT POP AND CLOSER TO THE SLIGHTLY WARMER MET MOS TEMPS PER MIXING/WARMING ALOFT. SHORTWAVE RIDGING BUILDS IN FOR MONDAY WITH ANOTHER DRAMATIC TURNAROUND IN TEMPS UNDER SUNSHINE AS 85H VALUES GO FROM BELOW 0C SUNDAY EVENING TO AS WARM AS +11C BY LATE MONDAY. THIS ALONG WITH VERY DRY AIR IN PLACE SHOULD SEND HIGHS ZOOMING BACK INTO THE 60S WEST AND AROUND 70 EAST UNDER DIMINISHING WINDS. RIDGING REMAINS IN PLACE MONDAY EVENING INTO TUESDAY WITH LARGE VALLEY/ELEVATION TEMP RANGE MONDAY NIGHT...THEN EVEN MILDER TUESDAY WITH MORE OF A WEST TO SW TRAJECTORY IN PLACE. CLOUDS MAY INCREASE FROM THE WEST LATER TUESDAY AHEAD OF THE NEXT FRONT BUT WITH ANY DEEPER MOISTURE REMAINING WEST OF THE REGION. THIS SHOULD PUSH HIGHS WELL INTO THE 70S EAST AND CLOSE TO 70 WEST OUTSIDE OF THE HIGHER ELEVATIONS. && .LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... AS OF 1145 AM EDT SATURDAY... BROAD UPPER RIDGING TO REMAIN IN PLACE UNTIL NEAR THE END OF THE PERIOD WITH SURFACE HIGH PRESSURE OFF THE SE COAST AND MEAN TROUGHING ACROSS THE CENTRAL AND SW STATES. WILL SEE A WEAK SURFACE FRONT PUSH SOUTH OF THE REGION WEDNESDAY AS A WAVE PASSES WELL TO THE NORTH AND HEIGHTS DIP A BIT. HOWEVER THIS BOUNDARY INITIALLY DRY WITH ONLY WEAK HIGH PRESSURE TO THE NW WHICH SHOULD DO LITTLE TO DETER VERY WARM TEMPS FOR MIDWEEK. FRONT LOOKS TO LIFT BACK NORTH THROUGH THE REGION THURSDAY AS STRONGER LOW PRESSURE PIVOTS TOWARD THE UPPER MIDWEST. BAND OF DEEPER MOISTURE/LIFT MAY TEND TO SPILL DOWN THE BAROCLINIC ZONE FROM THE WEST SO BUMPED UP POPS STARTING THURSDAY MORNING...CONTINUING INTO THURSDAY EVENING WITH MOISTURE AROUND AND WEAK IMPULSES SLIDING BY. STRONGER COLD FRONT WITH THE WAVE TO THE WEST WILL APPROACH FRIDAY AND SHOULD PASS ACROSS THE AREA FRIDAY NIGHT INTO EARLY SATURDAY PER THE FASTER EC. EXPECT PRE- FRONTAL BAND OF SHRA TO AFFECT MUCH OF THE REGION BY FRIDAY AFTERNOON WITH SOME ISOLATED TSRA POSSIBLE SOUTH AND SW SO RUNNING WITH CHANCE TO LOW LIKELY POPS INTO FRIDAY EVENING. BOUNDARY LOOKS TO GET FAR ENOUGH SE TO ALLOW DRYING ON SATURDAY WITH ONLY SOME EARLY CLOUDS/-SHRA MAINLY NW AND CLEARING ELSW PENDING LATER RUNS. GOOD SOUTH TO SW FLOW SHOULD FINALLY BRING TEMPS UP TO SPRING LEVELS AND ALLOW THEM TO STAY THERE WITH HIGHS MOSTLY 70S EXCEPT COOLING TO 60S SATURDAY BEHIND THE FRONT. LOWS WELL ABOVE FREEZING AND PERHAPS STAYING ABOVE 50 OUT EAST DURING MIDWEEK. && .AVIATION /20Z SATURDAY THROUGH THURSDAY/... AS OF 130 PM EDT SATURDAY... MOST TAF SITES ARE IN THE SOUP AHEAD OF LOW APPROACHING FROM THE SOUTHWEST. AS LOW TRACKS THROUGH THE AREA IT WILL SWING A STRONG COLD FRONT THROUGH...WHICH WILL SWEEP OUT THE FOG BUT BE FOLLOWED BY UPSLOPE SNOW SHOWERS OVERNIGHT...AND VERY STRONG WINDS LATE TONIGHT INTO SUNDAY. ONE BIG CHALLENGE IS WHAT HAPPENS TO CIGS/VSBYS AHEAD OF THE APPROACHING FRONT. WILL BASE THE EARLY CIGS/VSBYS ON TRENDS SHOWN IN HRRR AND LOCAL WRF MODEL RUN. WITH THIS IN MIND...EXPECT CIGS/VSBYS TO IMPROVE AHEAD OF CFROPA. BELIEVE THE HEAVIEST PCPN CAN BE EXPECTED JUST AHEAD AND ALONG THE FRONT AS IT PASSES. WILL TIME CFROPA AT KBLF/KLWB 23Z...KBKB 00Z...KROA 01Z...AND KLYH/KDAN 02Z. ANY EMBEDDED CONVECTION ALONG THE FRONT MAY CREATE SOME SIGNIFICANT LOCAL GUSTS BUT WILL NOT INDICATE THIS IN THE TAFS SINCE IT WILL BE NEARLY IMPOSSIBLE TO DO SO WITH ANY DEGREE OF ACCURACY. COLD AIR WILL BEGIN TO SURGE IN BEHIND THE FRONT AND EXPECT A TYPICAL NW FLOW SCENARIO WITH KBLF/KLWB SEEING BETTER CHANCES FOR -SHSN...KBCB ON THE EDGE...AND NOTHING FOR THE PIEDMONT DOWNSLOPE AREAS WORTH MENTIONING IN THE TAFS. THE BUILDING WINDS MAY TRANSLATE -SHSN A BIT FURTHER WEST BUT THE OVERALL FLAVOR WILL REMAIN THE SAME. EXPECT HIGHEST WIND GUSTS TO OCCUR AFTER DAYBREAK SUNDAY AS INSOLATION COMBINES WITH CAA TO MAXIMIZE MIXING. LOOKING DOWN THE ROAD...DRY WEATHER AND VFR CONDITIONS ARE EXPECTED MONDAY THROUGH TUESDAY. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...HIGH WIND WARNING FROM 10 PM THIS EVENING TO 10 PM EDT SUNDAY FOR VAZ009-012>020-022-032-033. WINTER WEATHER ADVISORY FROM MIDNIGHT TONIGHT TO 4 PM EDT SUNDAY FOR VAZ007-009>012-015-018>020. WIND ADVISORY FROM 10 PM THIS EVENING TO 10 PM EDT SUNDAY FOR VAZ007-010-011-023-024-034-035-043. NC...HIGH WIND WARNING FROM 10 PM THIS EVENING TO 10 PM EDT SUNDAY FOR NCZ001-002-018. WINTER WEATHER ADVISORY FROM MIDNIGHT TONIGHT TO 4 PM EDT SUNDAY FOR NCZ001-018. WIND ADVISORY FROM 10 PM THIS EVENING TO 10 PM EDT SUNDAY FOR NCZ003-019. WV...WINTER WEATHER ADVISORY FROM MIDNIGHT TONIGHT TO 4 PM EDT SUNDAY FOR WVZ042>045. WIND ADVISORY FROM 10 PM THIS EVENING TO 10 PM EDT SUNDAY FOR WVZ042-044. WINTER STORM WARNING FROM MIDNIGHT TONIGHT TO 4 PM EDT SUNDAY FOR WVZ042-043-045. && $$ SYNOPSIS...NF NEAR TERM...JH/NF SHORT TERM...JH LONG TERM...JH AVIATION...MBS
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1054 PM CDT SUN MAR 30 2014 UPDATED AVIATION PORTION FOR 06Z TAF ISSUANCE .SHORT TERM...TONIGHT AND MONDAY ISSUED AT 301 PM CDT SUN MAR 30 2014 LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW SURFACE HIGH PRESSURE EXTENDING FROM THE LOUISIANA COAST TO NORTHERN LAKE HURON EARLY THIS AFTERNOON. TEMPERATURES HAVE BEEN SLOW TO WARM SO FAR TODAY WITH READINGS RANGING FROM THE UPPER 30S AT STURGEON BAY AND MANITOWOC TO THE MIDDLE 50S AT WISCONSIN RAPIDS. MID AND HIGH CLOUDS CONTINUE TO STREAM ACROSS NORTHERN WISCONSIN AHEAD OF A SHORTWAVE MOVING ACROSS THE ROCKIES. NO SIGNS OF GULF MOISTURE ACROSS THE PLAINS JUST YET DESPITE PREVAILING SOUTHERLY FLOW. DEWPOINTS REMAIN IN THE UPPER 30S INTO CENTRAL TEXAS. THE MAIN FORECAST CONCERNS INCLUDE TEMPS TONIGHT AND CHANCES OF PRECIP ON MONDAY. TONIGHT...LOW PRESSURE WILL EMERGE INTO THE CENTRAL PLAINS WHILE A SURFACE WARM FRONT WILL DEVELOP OVER CENTRAL OR SOUTHERN WISCONSIN. AS HEIGHT FALLS OCCUR OVER THE PLAINS...RETURN FLOW AND 850MB THETAE ADVECTION WILL BE RAMPING UP OVER THE WESTERN GREAT LAKES. BUT THE AIR ACROSS THE CENTRAL PLAINS IS SO DRY THAT PRECIP CHANCES REMAIN TOO LOW TO INCLUDE IN THE FORECAST. SHOULD SEE A GRADUAL INCREASE IN MID AND HIGH CLOUDS HOWEVER. WITH WINDS SHIFTING TO THE SOUTHEAST NORTH OF THE WARM FRONT...SHOULD MAINTAIN DRY LOW LEVEL AIRMASS ENOUGH TO LIMIT THE THREAT OF FREEZING DRIZZLE OR FOG. TEMPS TO FALL INTO THE UPPER 20S OVER NE WISCONSIN TO THE UPPER 30S SOUTH. MONDAY...A STRONG SURFACE LOW WILL HEAD TOWARDS THE NORTHERN MISSISSIPPI VALLEY BY LATE IN THE AFTERNOON. MID AND HIGH CLOUDS WILL BE THICKENING AND LOWERING OVER THE COURSE OF THE DAY...BUT DRY AIR IN THE LOW LEVELS WILL BE HOLDING OFF PRECIP CHANCES FOR MUCH OF THE DAY. THINK PRECIP CHANCES WILL IMPROVE BY MID TO LATE AFTERNOON ACROSS THE FORECAST AREA...BUT UNSURE HOW PRECIP WILL EVOLVE. EVEN THOUGH MODELS POINT TOWARDS BETTER CHANCES ACROSS NORTHERN WISCONSIN...THINK INCREASING MOISTURE TRANSPORT ALOFT AND THE ARRIVAL OF A 700MB THETAE AXIS/EDGE OF DRY SLOT COULD LEAD TO A BROKEN BAND OF LIGHT SHOWERS AND SPRINKLES PUSHING ACROSS CENTRAL AND NORTH-CENTRAL WISCONSIN MID TO LATE AFTERNOON. MODIFIED POPS A BIT TO REFLECT THIS SCENARIO...BUT STILL KEPT POPS MAINLY IN THE CHANCE RANGE DUE TO CONCERNS OF DRY AIR IN THE LOW LEVELS. WITH THE WARM FRONT NOW EXPECTED TO STALL OVER CENTRAL WISCONSIN...TEMPS MAY NOT BE THAT MUCH DIFFERENT THAN TODAY...PERHAPS A COUPLE DEGREES WARMER. .LONG TERM...MONDAY NIGHT THROUGH SUNDAY ISSUED AT 301 PM CDT SUN MAR 30 2014 THE SHORTWAVE TROUGH WILL EXIT THE NORTHERN GREAT LAKES EARLY TUESDAY WITH COLDER AND DRIER AIR ARRIVING AT THE SURFACE. THE RAIN WILL CHANGE TO SNOW SHOWERS WITH AN INCH OR SO POSSIBLE IN THE NORTH. THEN A FLAT UPPER RIDGE ARRIVES WEDNESDAY AND THURSDAY WITH COLD HIGH PRESSURE CENTERED TO OUR NORTH. SO DRY AND SLIGHTLY COLDER THAN NORMAL FOR THIS TIME OF THE YEAR. THE NEXT SYSTEM FOR THURSDAY NIGHT AND FRIDAY IS NOW OVER THE CENTRAL PACIFIC SO WE WON/T HAVE TOO MUCH CONFIDENCE IN THE MODEL SOLUTIONS FOR A FEW MORE DAYS. IT DOES LOOK INTERESTING WITH ARCTIC HIGH PRESSURE TO THE NORTH AND EAST AND STRONG UPPER SYSTEM APPROACHING FROM THE SOUTHWEST. THE ARCTIC HIGH WILL DELIVER LOW LEVEL COLD DRY AIR SO SURFACE TEMPERATURES WILL LIKELY BE BELOW FREEZING BUT ABOVE FREEZING AIR AROUND 850MB COULD MAKE FOR A MIXTURE OF SNOW...SLEET OR FREEZING RAIN. && .AVIATION...FOR 06Z TAF ISSUANCE ISSUED AT 1042 PM CDT SUN MAR 30 2014 A WARM FRONT WILL STALL OVER CENTRAL WISCONSIN THROUGH MONDAY AS LOW PRESSURE MOVES ACROSS THE CENTRAL PLAINS. AHEAD OF THE SFC LOW...MID AND HIGH CLOUDS WILL STREAM ACROSS THE REGION. A LACK OF DEEP SATURATION WILL PREVENT ANY PCPN FROM FORMING THROUGH MONDAY MORNING. HOWEVER...AN UPPER LEVEL DISTURBANCE AND INCREASING LOW- LEVEL JET WILL CAUSE SCATTERED SHOWERS TO DEVELOP DURING THE AFTERNOON AND EVENING. ISOLD THUNDERSTORMS MAY ALSO OCCUR MONDAY EVENING...ALTHOUGH PROBABILITIES ARE TOO LOW TO MENTION IN THE TAFS AT THIS TIME. DESPITE THE POTENTIAL FOR PCPN...VFR CONDITIONS ARE EXPECTED TO PREVAIL THROUGH EARLY EVENING...WITH SOME MVFR CIGS DEVELOPING IN NC/C WI AS AN OCCLUDED FRONT ARRIVES TOWARD MIDNIGHT. MARGINAL LLWS IS POSSIBLE THROUGHOUT THE TAF PERIOD...BUT THE GREATEST THREAT SHOULD OCCUR DURING THE LATE AFTERNOON AND EVENING HOURS...WHEN SOUTH WINDS INCREASE TO 40-50 KTS JUST OFF THE SFC. WILL NEED TO WATCH FOR ADVECTION FOG DEVELOPMENT AS BETTER LOW- LEVEL MOISTURE OVERSPREADS THE DEEP SNOW COVER OVER NORTHERN WI MONDAY AFTERNOON/EVENING. RIGHT NOW...ONLY PLANNING TO MENTION LIGHT FOG IN THE TAFS. && .HYDROLOGY... ISSUED AT 301 PM CDT SUN MAR 30 2014 WARMER TEMPERATURES...MILDER WEATHER WILL PRODUCE MELTING SNOW AND ICE AND RESULT IN AN INCREASED CHANCE OF LOCAL FLOODING EARLY THIS WEEK. THE SNOW IS VERY DEEP IN THE NORTH AND SHOULD BE ABLE TO ABSORB RAINFALL WITHOUT FULLY MELTING. HOWEVER...PLACES WITH JUST A FEW INCHES LEFT ON THE GROUND MAY HAVE MOST OF THE SNOW MELT...WHICH MAY CAUSE RIVERS AND STREAMS TO RISE. THERE IS ALSO A CHANCE OF ICE JAMS AS RIVER ICE BREAKS UP. A HYDROLOGICAL OUTLOOK IS IN EFFECT. && .GRB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM.....MPC LONG TERM......RDM AVIATION.......KIECKBUSCH HYDROLOGY......RDM
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
637 PM CDT SUN MAR 30 2014 UPDATED AVIATION PORTION FOR 00Z TAF ISSUANCE .SHORT TERM...TONIGHT AND MONDAY ISSUED AT 301 PM CDT SUN MAR 30 2014 LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW SURFACE HIGH PRESSURE EXTENDING FROM THE LOUISIANA COAST TO NORTHERN LAKE HURON EARLY THIS AFTERNOON. TEMPERATURES HAVE BEEN SLOW TO WARM SO FAR TODAY WITH READINGS RANGING FROM THE UPPER 30S AT STURGEON BAY AND MANITOWOC TO THE MIDDLE 50S AT WISCONSIN RAPIDS. MID AND HIGH CLOUDS CONTINUE TO STREAM ACROSS NORTHERN WISCONSIN AHEAD OF A SHORTWAVE MOVING ACROSS THE ROCKIES. NO SIGNS OF GULF MOISTURE ACROSS THE PLAINS JUST YET DESPITE PREVAILING SOUTHERLY FLOW. DEWPOINTS REMAIN IN THE UPPER 30S INTO CENTRAL TEXAS. THE MAIN FORECAST CONCERNS INCLUDE TEMPS TONIGHT AND CHANCES OF PRECIP ON MONDAY. TONIGHT...LOW PRESSURE WILL EMERGE INTO THE CENTRAL PLAINS WHILE A SURFACE WARM FRONT WILL DEVELOP OVER CENTRAL OR SOUTHERN WISCONSIN. AS HEIGHT FALLS OCCUR OVER THE PLAINS...RETURN FLOW AND 850MB THETAE ADVECTION WILL BE RAMPING UP OVER THE WESTERN GREAT LAKES. BUT THE AIR ACROSS THE CENTRAL PLAINS IS SO DRY THAT PRECIP CHANCES REMAIN TOO LOW TO INCLUDE IN THE FORECAST. SHOULD SEE A GRADUAL INCREASE IN MID AND HIGH CLOUDS HOWEVER. WITH WINDS SHIFTING TO THE SOUTHEAST NORTH OF THE WARM FRONT...SHOULD MAINTAIN DRY LOW LEVEL AIRMASS ENOUGH TO LIMIT THE THREAT OF FREEZING DRIZZLE OR FOG. TEMPS TO FALL INTO THE UPPER 20S OVER NE WISCONSIN TO THE UPPER 30S SOUTH. MONDAY...A STRONG SURFACE LOW WILL HEAD TOWARDS THE NORTHERN MISSISSIPPI VALLEY BY LATE IN THE AFTERNOON. MID AND HIGH CLOUDS WILL BE THICKENING AND LOWERING OVER THE COURSE OF THE DAY...BUT DRY AIR IN THE LOW LEVELS WILL BE HOLDING OFF PRECIP CHANCES FOR MUCH OF THE DAY. THINK PRECIP CHANCES WILL IMPROVE BY MID TO LATE AFTERNOON ACROSS THE FORECAST AREA...BUT UNSURE HOW PRECIP WILL EVOLVE. EVEN THOUGH MODELS POINT TOWARDS BETTER CHANCES ACROSS NORTHERN WISCONSIN...THINK INCREASING MOISTURE TRANSPORT ALOFT AND THE ARRIVAL OF A 700MB THETAE AXIS/EDGE OF DRY SLOT COULD LEAD TO A BROKEN BAND OF LIGHT SHOWERS AND SPRINKLES PUSHING ACROSS CENTRAL AND NORTH-CENTRAL WISCONSIN MID TO LATE AFTERNOON. MODIFIED POPS A BIT TO REFLECT THIS SCENARIO...BUT STILL KEPT POPS MAINLY IN THE CHANCE RANGE DUE TO CONCERNS OF DRY AIR IN THE LOW LEVELS. WITH THE WARM FRONT NOW EXPECTED TO STALL OVER CENTRAL WISCONSIN...TEMPS MAY NOT BE THAT MUCH DIFFERENT THAN TODAY...PERHAPS A COUPLE DEGREES WARMER. .LONG TERM...MONDAY NIGHT THROUGH SUNDAY ISSUED AT 301 PM CDT SUN MAR 30 2014 THE SHORTWAVE TROUGH WILL EXIT THE NORTHERN GREAT LAKES EARLY TUESDAY WITH COLDER AND DRIER AIR ARRIVING AT THE SURFACE. THE RAIN WILL CHANGE TO SNOW SHOWERS WITH AN INCH OR SO POSSIBLE IN THE NORTH. THEN A FLAT UPPER RIDGE ARRIVES WEDNESDAY AND THURSDAY WITH COLD HIGH PRESSURE CENTERED TO OUR NORTH. SO DRY AND SLIGHTLY COLDER THAN NORMAL FOR THIS TIME OF THE YEAR. THE NEXT SYSTEM FOR THURSDAY NIGHT AND FRIDAY IS NOW OVER THE CENTRAL PACIFIC SO WE WON/T HAVE TOO MUCH CONFIDENCE IN THE MODEL SOLUTIONS FOR A FEW MORE DAYS. IT DOES LOOK INTERESTING WITH ARCTIC HIGH PRESSURE TO THE NORTH AND EAST AND STRONG UPPER SYSTEM APPROACHING FROM THE SOUTHWEST. THE ARCTIC HIGH WILL DELIVER LOW LEVEL COLD DRY AIR SO SURFACE TEMPERATURES WILL LIKELY BE BELOW FREEZING BUT ABOVE FREEZING AIR AROUND 850MB COULD MAKE FOR A MIXTURE OF SNOW...SLEET OR FREEZING RAIN. && .AVIATION...FOR 00Z TAF ISSUANCE ISSUED AT 629 PM CDT SUN MAR 30 2014 A WARM FRONT WILL STALL OVER CENTRAL WISCONSIN AS LOW PRESSURE MOVES ACROSS THE CENTRAL PLAINS. AHEAD OF THE LOW...MID AND HIGH CLOUDS WILL INCREASE ACROSS THE REGION. A LACK OF DEEP SATURATION WILL PREVENT ANY PCPN FROM FORMING THROUGH MONDAY MORNING. HOWEVER... AN UPPER LEVEL DISTURBANCE AND INCREASING LOW-LEVEL JET WILL CAUSE SCATTERED SHOWERS TO DEVELOP DURING THE AFTERNOON. DESPITE THE POTENTIAL FOR PCPN...VFR CONDITIONS ARE EXPECTED TO PREVAIL THROUGH THE PERIOD. HAVE BACKED OFF A BIT ON THE LLWS IN THE TAFS...AS IT APPEARS VERY MARGINAL THROUGH MIDDAY MONDAY. DECIDED TO FOCUS ON A PERIOD OF BETTER LLWS POTENTIAL DURING THE MID TO LATE AFTERNOON ON MONDAY...AS SOUTH WINDS INCREASE TO 40-50 KTS JUST OFF THE SFC. && .HYDROLOGY... ISSUED AT 301 PM CDT SUN MAR 30 2014 WARMER TEMPERATURES...MILDER WEATHER WILL PRODUCE MELTING SNOW AND ICE AND RESULT IN AN INCREASED CHANCE OF LOCAL FLOODING EARLY THIS WEEK. THE SNOW IS VERY DEEP IN THE NORTH AND SHOULD BE ABLE TO ABSORB RAINFALL WITHOUT FULLY MELTING. HOWEVER...PLACES WITH JUST A FEW INCHES LEFT ON THE GROUND MAY HAVE MOST OF THE SNOW MELT...WHICH MAY CAUSE RIVERS AND STREAMS TO RISE. THERE IS ALSO A CHANCE OF ICE JAMS AS RIVER ICE BREAKS UP. A HYDROLOGICAL OUTLOOK IS IN EFFECT. && .GRB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM.....MPC LONG TERM......RDM AVIATION.......KIECKBUSCH HYDROLOGY......RDM
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
553 PM CDT SAT MAR 29 2014 UPDATED AVIATION PORTION FOR 00Z TAF ISSUANCE .SHORT TERM...TONIGHT AND SUNDAY ISSUED AT 248 PM CDT SAT MAR 29 2014 THE LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW HIGH PRESSURE STRETCHING FROM QUEBEC TO THE WESTERN GREAT LAKES TO THE STATE OF TEXAS. EARLIER RIBBON OF STRATO-CU OVER PARTS OF CENTRAL AND NORTHEAST WISCONSIN DISSIPATED AROUND MIDDAY LEAVING MOSTLY SUNNY CONDITIONS ACROSS THE NORTHERN HALF OF THE STATE. LOOKING UPSTREAM...THE JET IS PUSHING MID AND HIGH CLOUDS TO THE EAST ACROSS THE PLAINS. BUT OTHERWISE QUIET CONDITIONS EXIST UNTIL NORTHWEST MONTANA IN THE VICINITY OF SHORTWAVE ENERGY. WITH THAT SHORTWAVE EXPECTED TO PASS NORTH OF THE REGION...THE MAIN FORECAST CONCERNS INCLUDE CLOUDS AND TEMPS IN THE SHORT TERM. TONIGHT...SURFACE HIGH PRESSURE WILL SHIFT FROM THE WESTERN TO THE CENTRAL GREAT LAKES WHILE THE MID-LEVEL RIDGE AXIS WORKS ACROSS THE STATE. SHORTWAVE ENERGY MOVING ACROSS SOUTHERN CANADA WILL SEND MID AND HIGH CLOUDS ACROSS NORTHERN MINNESOTA AND LAKE SUPERIOR. BUT SOME OF THESE CLOUDS WILL LIKELY GRAZE NORTHERN WISCONSIN. OTHERWISE...MOSTLY CLEAR TO CLEAR CONDITIONS WILL PREVAIL. DEVELOPING SOUTHEAST WINDS WILL LIKELY TEMP KEEPS FROM PLUMMETING OVER THE DEEP SNOW PACK OF N-C WISCONSIN. TEMPS MAINLY IN THE 20...EXCEPT FOR A FEW TEENS OVER FAR NE WISCONSIN. SUNDAY...RETURN FLOW WILL BE RAMPING UP THROUGH THE DAY AS LOW PRESSURE EMERGES INTO THE CENTRAL PLAINS. AT THE SAME TIME...A COLD FRONT WILL BE SAGGING SOUTHEAST ACROSS MINNESOTA AND INTO FAR NW WISCONSIN BY LATE IN THE AFTERNOON. SOUTH TO SOUTHEAST WINDS WILL BE ADVECTING WARMER AIR IN THE LOW LEVELS WHICH WILL LEAD TO A WARMER DAY ACROSS THE REGION. THE EXCEPTION WILL BE ALONG THE LAKE AND BAY SHORE WHERE ONSHORE FLOW WILL PUSH IN A COLD MARINE LAYER. SO WILL GO WITH HIGHS IN THE UPPER 50S IN THE WARM SPOTS...TO THE UPPER 30S ALONG LAKE MICHIGAN. SHOULD SEE MORE IN THE WAY OF MID AND HIGH CLOUDS WHICH WILL PROVIDE FILTERED SUNSHINE AT TIMES...BUT DO NOT THINK THEY WILL HAVE MUCH IMPACT ON TEMPS. .LONG TERM...SUNDAY NIGHT THROUGH SATURDAY ISSUED AT 248 PM CDT SAT MAR 29 2014 THE MODELS ARE NOW IN FAIRLY GOOD AGREEMENT THAT THE SYSTEM MOVING OUT OF THE CENTRAL PLAINS WILL TRACK TO THE WEST OF OUR FORECAST AREA...RESULTING IN MOSTLY RAIN AND A CHANCE OF THUNDERSTORMS. THE RAIN SHOULD ARRIVE FROM WEST TO EAST MONDAY AFTERNOON AND CONTINUE MONDAY NIGHT. COLDER AIR AND SNOW SHOWERS ARE LIKELY TUESDAY. THE MAIN CONCERN FROM THE RAIN AND WARMER TEMPERATURES IS MELTING SNOW AND RIVER ICE WITH THE POSSIBILITY OF LOCAL FLOODING. HIGH PRESSURE BUILDS IN TUESDAY NIGHT AND WEDNESDAY BEFORE ANOTHER SYSTEM APPROACHES FROM THE SOUTHERN PLAINS. THE GFS IS MUCH FASTER AND FLATTER WITH THE SURFACE SYSTEM AND WE WOULD BE IN THE NORTHERN FRINGE OF IT AND RECEIVE SOME SNOW WHILE THE ECMWF IS SLOWER AND STRONGER AND WE WOULD HAVE PRECIPITATION TYPE ISSUES DUE TO A MORE NORTHERLY TRACK. THEN A LITTLE COLDER AND DRY WEATHER EXPECTED FRIDAY AND SATURDAY. && .AVIATION...FOR 00Z TAF ISSUANCE ISSUED AT 520 PM CDT SAT MAR 29 2014 CLEAR SKIES HAVE PREVAILED OVER NORTHEAST WISCONSIN THIS EVENING. THE QUIET VFR CONDITIONS WILL PREVAIL THROUGH THE TONIGHT. MID- LEVEL CLOUDS WILL BE ON THE INCREASE SUNDAY MORNING AND THEN STICK AROUND FOR THE REST OF THE DAY...HOWEVER VFR CONDITIONS ARE EXPECTED. AFTER LIGHT WINDS TONIGHT...EXPECT SOUTHEAST WINDS TO INCREASE SUNDAY MORNING. && .HYDROLOGY... ISSUED AT 248 PM CDT SAT MAR 29 2014 WARMER TEMPERATURES...MELTING SNOW AND RAIN WILL PRODUCE AN INCREASE IN THE CHANCES OF LOCAL FLOODING EARLY NEXT WEEK. THE SNOW IS VERY DEEP IN THE NORTH AND SHOULD BE ABLE TO ABSORB THE RAINFALL WITHOUT FULLY MELTING BUT PLACES WITH JUST A FEW INCHES LEFT MAY HAVE MOST OF IT MELT AND RUN OFF THE FROZEN GROUND INTO RIVERS AND STREAMS. THERE IS ALSO A CHANCE OF ICE JAMS AS RIVER ICE BREAKS UP. WE HAVE A HYDROLOGICAL OUTLOOK IN EFFECT. && .GRB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM.....MPC LONG TERM......RDM AVIATION.......WOLF HYDROLOGY......RDM
FORECAST DISCUSSION FOR ROUTINE AFTERNOON FORECAST ISSUANCE

.SHORT TERM...TONIGHT AND SUNDAY ISSUED AT 248 PM CDT SAT MAR 29 2014 THE LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW HIGH PRESSURE STRETCHING FROM QUEBEC TO THE WESTERN GREAT LAKES TO THE STATE OF TEXAS. EARLIER RIBBON OF STRATO-CU OVER PARTS OF CENTRAL AND NORTHEAST WISCONSIN DISSIPATED AROUND MIDDAY LEAVING MOSTLY SUNNY CONDITIONS ACROSS THE NORTHERN HALF OF THE STATE. LOOKING UPSTREAM...THE JET IS PUSHING MID AND HIGH CLOUDS TO THE EAST ACROSS THE PLAINS. BUT OTHERWISE QUIET CONDITIONS EXIST UNTIL NORTHWEST MONTANA IN THE VICINITY OF SHORTWAVE ENERGY. WITH THAT SHORTWAVE EXPECTED TO PASS NORTH OF THE REGION...THE MAIN FORECAST CONCERNS INCLUDE CLOUDS AND TEMPS IN THE SHORT TERM. TONIGHT...SURFACE HIGH PRESSURE WILL SHIFT FROM THE WESTERN TO THE CENTRAL GREAT LAKES WHILE THE MID-LEVEL RIDGE AXIS WORKS ACROSS THE STATE. SHORTWAVE ENERGY MOVING ACROSS SOUTHERN CANADA WILL SEND MID AND HIGH CLOUDS ACROSS NORTHERN MINNESOTA AND LAKE SUPERIOR. BUT SOME OF THESE CLOUDS WILL LIKELY GRAZE NORTHERN WISCONSIN. OTHERWISE...MOSTLY CLEAR TO CLEAR CONDITIONS WILL PREVAIL. DEVELOPING SOUTHEAST WINDS WILL LIKELY TEMP KEEPS FROM PLUMMETING OVER THE DEEP SNOW PACK OF N-C WISCONSIN. TEMPS MAINLY IN THE 20...EXCEPT FOR A FEW TEENS OVER FAR NE WISCONSIN. SUNDAY...RETURN FLOW WILL BE RAMPING UP THROUGH THE DAY AS LOW PRESSURE EMERGES INTO THE CENTRAL PLAINS. AT THE SAME TIME...A COLD FRONT WILL BE SAGGING SOUTHEAST ACROSS MINNESOTA AND INTO FAR NW WISCONSIN BY LATE IN THE AFTERNOON. SOUTH TO SOUTHEAST WINDS WILL BE ADVECTING WARMER AIR IN THE LOW LEVELS WHICH WILL LEAD TO A WARMER DAY ACROSS THE REGION. THE EXCEPTION WILL BE ALONG THE LAKE AND BAY SHORE WHERE ONSHORE FLOW WILL PUSH IN A COLD MARINE LAYER. SO WILL GO WITH HIGHS IN THE UPPER 50S IN THE WARM SPOTS...TO THE UPPER 30S ALONG LAKE MICHIGAN. SHOULD SEE MORE IN THE WAY OF MID AND HIGH CLOUDS WHICH WILL PROVIDE FILTERED SUNSHINE AT TIMES...BUT DO NOT THINK THEY WILL HAVE MUCH IMPACT ON TEMPS. .LONG TERM...SUNDAY NIGHT THROUGH SATURDAY ISSUED AT 248 PM CDT SAT MAR 29 2014 THE MODELS ARE NOW IN FAIRLY GOOD AGREEMENT THAT THE SYSTEM MOVING OUT OF THE CENTRAL PLAINS WILL TRACK TO THE WEST OF OUR FORECAST AREA...RESULTING IN MOSTLY RAIN AND A CHANCE OF THUNDERSTORMS. THE RAIN SHOULD ARRIVE FROM WEST TO EAST MONDAY AFTERNOON AND CONTINUE MONDAY NIGHT. COLDER AIR AND SNOW SHOWERS ARE LIKELY TUESDAY. THE MAIN CONCERN FROM THE RAIN AND WARMER TEMPERATURES IS MELTING SNOW AND RIVER ICE WITH THE POSSIBILITY OF LOCAL FLOODING. HIGH PRESSURE BUILDS IN TUESDAY NIGHT AND WEDNESDAY BEFORE ANOTHER SYSTEM APPROACHES FROM THE SOUTHERN PLAINS. THE GFS IS MUCH FASTER AND FLATTER WITH THE SURFACE SYSTEM AND WE WOULD BE IN THE NORTHERN FRINGE OF IT AND RECEIVE SOME SNOW WHILE THE ECMWF IS SLOWER AND STRONGER AND WE WOULD HAVE PRECIPITATION TYPE ISSUES DUE TO A MORE NORTHERLY TRACK. THEN A LITTLE COLDER AND DRY WEATHER EXPECTED FRIDAY AND SATURDAY. && .AVIATION...FOR 18Z TAF ISSUANCE ISSUED AT 1229 PM CDT SAT MAR 29 2014 SCT TO BKN MVFR CIGS ACROSS NORTH-CENTRAL AND NORTHEAST WISCONSIN HAVE TURNED VFR LATE THIS MORNING AND HAVE NEARLY DISSIPATED. THEREFORE...EXPECT FEW CLOUD COVERAGE AT TAF ISSUANCE WHICH SHOULD BECOME SKC LATER IN THE AFTERNOON. QUIET CONDITIONS WILL PREVAIL TONIGHT WITH LIGHT WINDS. THEN MID-LEVEL CLOUDS WILL BE ON THE INCREASE SUNDAY MORNING WHILE SOUTHEAST WINDS WILL INCREASE AT THE SAME TIME. && .HYDROLOGY... ISSUED AT 248 PM CDT SAT MAR 29 2014 WARMER TEMPERATURES...MELTING SNOW AND RAIN WILL PRODUCE AN INCREASE IN THE CHANCES OF LOCAL FLOODING EARLY NEXT WEEK. THE SNOW IS VERY DEEP IN THE NORTH AND SHOULD BE ABLE TO ABSORB THE RAINFALL WITHOUT FULLY MELTING BUT PLACES WITH JUST A FEW INCHES LEFT MAY HAVE MOST OF IT MELT AND RUN OFF THE FROZEN GROUND INTO RIVERS AND STREAMS. THERE IS ALSO A CHANCE OF ICE JAMS AS RIVER ICE BREAKS UP. WE HAVE A HYDROLOGICAL OUTLOOK IN EFFECT. && .GRB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM.....MPC LONG TERM......RDM AVIATION.......MPC HYDROLOGY......RDM
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1242 PM CDT SAT MAR 29 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 328 AM CDT SAT MAR 29 2014 CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS SHOWED A VERY DEEP TROUGH OFF THE PACIFIC NORTHWEST...RIDGING PUSHING EASTWARD ACROSS THE ROCKIES...AND TROUGHING FROM MINNESOTA SOUTH INTO ARKANSAS. THE NORTHERN PORTION OF THIS TROUGH HAS BEEN UNEVENTFUL FOR THE FORECAST AREA...BRINGING ONLY SOME MID/HIGH CLOUDS. DRY AIR SITUATED BETWEEN 900-700MB ON THE 00Z GRB...MPX AND DVN SOUNDINGS KEPT ANY POTENTIAL PRECIPITATION FROM THESE CLOUDS FROM REACHING THE GROUND. HOWEVER...AT AND BELOW 900MB... OBSERVATIONS ARE SHOWING SOME LOW STRATUS DEVELOPING ACROSS SOUTHERN WI. THIS STRATUS IS A RESULT OF EASTERLY FLOW OF MOISTURE FROM LAKE MICHIGAN COMBINING WITH NOCTURNAL COOLING AND AN INVERTED SURFACE TROUGH IN THE AREA. TO THE NORTHWEST...CLEARING ASSOCIATED WITH SURFACE HIGH PRESSURE WAS PRESENT ACROSS MUCH OF MINNESOTA. AIRMASS OVER THE UPPER MIDWEST STILL RELATIVELY COOL WITH 00Z RAOBS SHOWING 925MB TEMPS OF -3 TO -5C FROM THE FORECAST AREA TO BIS. HOWEVER...LBF AND UNR ON THE BACK SIDE OF THE SURFACE HIGH WERE MUCH WARMER AT +11 AND +15C RESPECTIVELY. A PROGRESSIVE UPPER FLOW PATTERN IS PROGGED THROUGH THE SHORT TERM PERIOD AS A VIGOROUS SHORTWAVE AT THE BOTTOM OF THE EAST PACIFIC TROUGH...NEAR 35 NORTH / 140 WEST...MOVES INTO CALIFORNIA. FOR COMPARISON...THE FORECAST AREA GOES FROM UNDER A SHORTWAVE TROUGH AXIS AT 12Z SATURDAY TO A RIDGE AXIS AT 12Z SUNDAY. 3 MAIN IMPACTS FROM THIS SWITCH: 1. SUBSIDENCE AND DRYING ASSOCIATED WITH BUILDING UPPER RIDGING WILL HELP CLEAR OUT ANY LOW CLOUDS BY 18Z...LEADING TO A SUNNY AFTERNOON WITH JUST SOME SCATTERED CIRRUS TONIGHT. 2. AFTER MOSTLY A LIGHT WIND FLOW TODAY AS SURFACE RIDGE MOVES THROUGH...SOUTHERLY WINDS INCREASE GREATLY TONIGHT...ESPECIALLY FROM 925-850MB. BY 12Z SUNDAY...THEY ARE RUNNING BETWEEN 40-50 KT. 3. 925-850MB TEMPS FOLLOW THE INCREASE IN WINDS. FOR EXAMPLE... 925MB TEMPS AFTER STARTING OFF BETWEEN -2 TO -5C AT 12Z THIS MORNING CLIMB TO 0 TO +3C AT 00Z SUNDAY...THEN TO 2 TO +5C AT 12Z SUNDAY. SUNSHINE SHOULD EASILY BOOST HIGHS INTO THE 40S TODAY AT MOST LOCATIONS...WITH A FEW VALLEY AREAS APPROACHING 50. TEMPERATURES SHOULD BOTTOM OUT THIS EVENING BEFORE THE LOW LEVEL JET INCREASES AND CAUSES THEM TO STABILIZE. READINGS SHOULD RISE LATE TONIGHT AS THE WARMER AIR FLOWS IN. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 328 AM CDT SAT MAR 29 2014 MANY WEATHER CONCERNS TO HIGHLIGHT DURING THE LONG TERM PERIOD AS THE FORECAST AREA LOOKS TO RESIDE MUCH OF THE TIME IN SOUTHWEST FLOW ALOFT. 1. ABOVE NORMAL TEMPERATURES SUNDAY THROUGH MONDAY. THE VIGOROUS SHORTWAVE COMING INTO CALIFORNIA TONIGHT REMAINS ON TRACK TO LIFT INTO EASTERN SOUTH DAKOTA OR SOUTHWEST MN BY 00Z TUESDAY...PUSHING WARM...DOWNSLOPED AIR OFF THE ROCKIES INTO THE FORECAST AREA AHEAD OF IT. 925MB TEMPS ARE PROGGED TO CLIMB TO 9-13C BY 00Z MONDAY...COOLEST OVER TAYLOR/CLARK COUNTIES. THESE READINGS COMBINED WITH SUN THROUGH SCT-BKN CIRRUS AND BREEZY SOUTHERLY WINDS SHOULD PUSH TEMPERATURES INTO THE 60S ALONG/SOUTHWEST OF I-94...WITH 50S TO THE NORTH. A SOUTHERLY BREEZE PERSISTS INTO SUNDAY NIGHT AND MONDAY. THIS WIND SHOULD ONLY ALLOW TEMPERATURES TO FALL INTO THE 40S SUNDAY NIGHT...WITH MAYBE SOME 30S IN THE TYPICAL COLD SPOTS. THEN ON MONDAY...WITH MODEL CONSENSUS KEEPING THE FORECAST AREA IN THE WARM SECTOR HIGHLIGHTED BY 925MB TEMPS OF 9-13C...SHOULD SEE ANOTHER DAY OF HIGHS MOSTLY IN THE MID 50S TO MID 60S. THIS OCCURS DESPITE SOME WARM ADVECTION PRECIPITATION MOVING THROUGH. 2. PRECIPITATION AND THUNDERSTORM POTENTIAL MONDAY INTO MONDAY NIGHT. THE SIGNAL STILL EXISTS FOR A WARM CONVEYOR BELT OF SHOWERS TO MOVE ACROSS THE FORECAST AREA...ESPECIALLY DURING THE LATE MORNING AND AFTERNOON HOURS...AS ISENTROPIC LIFT ON 300K SURFACES AND ABOVE INCREASES. THE BEST MOISTURE EXISTS NORTH OF I- 90...THUS HIGHEST CHANCES OF 50-70 ARE SITUATED THERE. THE POTENTIAL STILL EXISTS FOR A BAND OF SHOWERS AND SOME EMBEDDED THUNDERSTORMS TO FORM ALONG THE COLD FRONT CROSSING LATE IN THE AFTERNOON AND EVENING. HOWEVER...A COUPLE OF CONCERNS FOR THIS BAND INCLUDE MODELS MAY BE OVERDOING THE MOISTURE RETURN AND NOT MIXING DEWPOINTS OUT ENOUGH...AND THE TIME OF DAY IS BEING PUSHED TO OUTSIDE OF PEAK HEATING. SHOULD STORMS FIRE...THERE REMAINS AMPLE SHEAR TO ALLOW FOR SEVERE WEATHER. LASTLY...CONFIDENCE HAS INCREASED THAT THE DEFORMATION BAND ON THE NORTHWEST SIDE OF THE ASSOCIATED SURFACE LOW WILL TRACK NORTHWEST OF THE FORECAST AREA ON MONDAY...AND CLIP THE NORTHWEST HALF OF THE FORECAST AREA MONDAY NIGHT BEFORE LIFTING OFF TO THE NORTHEAST. COLDER AIR RUSHING IN SHOULD ALLOW FOR A CHANGEOVER TO SNOW...WITH A BRIEF PERIOD OF SLEET POSSIBLE DURING THIS CHANGEOVER AS COLD AIR UNDERCUTS WARMER AIR ALOFT. LITTLE SNOW ACCUMULATION IS EXPECTED...THOUGH. THERE IS ALSO POTENTIAL TO LOSE ICE IN THE CLOUDS DUE TO A DRY SLOT...BUT THE LOSS OF ICE OCCURS EITHER WHERE TEMPERATURES ARE ABOVE FREEZING TO RESULT IN RAIN OR WHERE NO PRECIPITATION WILL OCCUR. 3. WINDS MONDAY AFTERNOON AND NIGHT. ECMWF/GFS PROG 925MB WINDS OF 30-40 KT SOUTH OF I-90 DURING THE AFTERNOON. IF MORE SUN OCCURS THAN EXPECTED...THESE COULD EASILY MIX DOWN TO THE SURFACE AND SEE BOTH SUSTAINED WINDS AND GUSTS APPROACH ADVISORY. INCREASED WINDS AND GUSTS AS A RESULT. ALSO...AS THE LOW PASSES TO OUR NORTHEAST...A TIGHT PRESSURE GRADIENT WITH 925MB WINDS OF 30-40 KT FROM THE SOUTHWEST TO WEST USHERS IN COLD AIR. WITH SOME ISALLOBARIC AID...COULD SEE GUSTS HERE TOO APPROACH ADVISORY FOR A BRIEF TIME. 4. WINTRY MIX POTENTIAL LATE TUESDAY NIGHT THROUGH FRIDAY. MODELS ARE AT ODDS ON HOW TO HANDLE THE EJECTION OF TROUGHING OUT OF THE SOUTHWESTERN U.S. ON TUESDAY TOWARDS THE REGION LATER IN THE WEEK. THERE WILL NO DOUBT BE A COLDER DOME OF HIGH PRESSURE INFLUENCING THE AREA...LIKELY SITUATED FROM NORTHERN MN INTO UPPER MI. IN ADDITION...AS THE TROUGH EJECTS...ISENTROPIC LIFT OF WARMER...GULF OF MEXICO MOISTURE WILL SPREAD PRECIPITATION NORTH TOWARDS THE FORECAST AREA. THIS SETS UP CONCERN FOR THE WINTRY MIX. FOR NOW HAVE FOLLOWED A MODEL CONSENSUS WITH PRECIPITATION CHANCES...WHICH SEEMS MOST LIKELY TO OCCUR WEDNESDAY SOUTH OF I-90. ALSO KEPT TYPES AS RAIN/SNOW BASED ON HOURLY TEMPERATURES...BUT THERE IS DEFINITELY POTENTIAL FOR SLEET AND FREEZING RAIN/DRIZZLE AT TIMES. 29.00Z ECMWF EVEN PRODUCES AT LEAST ADVISORY WORTHY SNOWFALL OVER THE NORTHWEST HALF OF THE AREA THURSDAY AND THURSDAY NIGHT. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 1240 PM CDT SAT MAR 29 2014 VFR CONDITONS EXPECTED BUT LOW-LEVEL WINDS WILL BE ON THE INCREASE OVERNIGHT. WITH A STRONG INVERSION IN PLACE OVER THE TAF SITES...WINDS WILL INCREASE IN THE LOWEST 2KFT RAPIDLY. HAVE INCLUDED LLWS FOR KRST FOR A PERIOD SUNDAY MORNING. && .HYDROLOGY... ISSUED AT 328 AM CDT SAT MAR 29 2014 MAIN FOCUS FOR RIVER ISSUES FROM THE RECENT RAIN IS ON THE KICKAPOO RIVER. SOME LOCATIONS ALONG IT ARE EITHER IN OR EXPECTED TO REACH FLOOD STAGE AS RUNOFF CONTINUES TO WORK ITS WAY DOWNSTREAM. FROM SUNDAY INTO MONDAY NIGHT...THE RAPID WARM UP WILL CAUSE THE SNOW PACK NORTH OF INTERSTATE 94 TO MELT RAPIDLY. IN ADDITION WITH FROZEN GROUND...ANY RAINFALL ON MONDAY AND MONDAY NIGHT WILL QUICKLY RUNOFF INTO AREA RIVERS AND STREAMS. THIS WILL RESULT IN RISES ALONG THE BLACK...BUFFALO...AND TREMPEALEAU RIVERS IN WESTERN WISCONSIN. SOME FLOODING IS ALSO A POSSIBILITY. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...AJ LONG TERM...AJ AVIATION...BAUMGARDT HYDROLOGY...AJ
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
709 AM CDT SAT MAR 29 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 328 AM CDT SAT MAR 29 2014 CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS SHOWED A VERY DEEP TROUGH OFF THE PACIFIC NORTHWEST...RIDGING PUSHING EASTWARD ACROSS THE ROCKIES...AND TROUGHING FROM MINNESOTA SOUTH INTO ARKANSAS. THE NORTHERN PORTION OF THIS TROUGH HAS BEEN UNEVENTFUL FOR THE FORECAST AREA...BRINGING ONLY SOME MID/HIGH CLOUDS. DRY AIR SITUATED BETWEEN 900-700MB ON THE 00Z GRB...MPX AND DVN SOUNDINGS KEPT ANY POTENTIAL PRECIPITATION FROM THESE CLOUDS FROM REACHING THE GROUND. HOWEVER...AT AND BELOW 900MB... OBSERVATIONS ARE SHOWING SOME LOW STRATUS DEVELOPING ACROSS SOUTHERN WI. THIS STRATUS IS A RESULT OF EASTERLY FLOW OF MOISTURE FROM LAKE MICHIGAN COMBINING WITH NOCTURNAL COOLING AND AN INVERTED SURFACE TROUGH IN THE AREA. TO THE NORTHWEST...CLEARING ASSOCIATED WITH SURFACE HIGH PRESSURE WAS PRESENT ACROSS MUCH OF MINNESOTA. AIRMASS OVER THE UPPER MIDWEST STILL RELATIVELY COOL WITH 00Z RAOBS SHOWING 925MB TEMPS OF -3 TO -5C FROM THE FORECAST AREA TO BIS. HOWEVER...LBF AND UNR ON THE BACK SIDE OF THE SURFACE HIGH WERE MUCH WARMER AT +11 AND +15C RESPECTIVELY. A PROGRESSIVE UPPER FLOW PATTERN IS PROGGED THROUGH THE SHORT TERM PERIOD AS A VIGOROUS SHORTWAVE AT THE BOTTOM OF THE EAST PACIFIC TROUGH...NEAR 35 NORTH / 140 WEST...MOVES INTO CALIFORNIA. FOR COMPARISON...THE FORECAST AREA GOES FROM UNDER A SHORTWAVE TROUGH AXIS AT 12Z SATURDAY TO A RIDGE AXIS AT 12Z SUNDAY. 3 MAIN IMPACTS FROM THIS SWITCH: 1. SUBSIDENCE AND DRYING ASSOCIATED WITH BUILDING UPPER RIDGING WILL HELP CLEAR OUT ANY LOW CLOUDS BY 18Z...LEADING TO A SUNNY AFTERNOON WITH JUST SOME SCATTERED CIRRUS TONIGHT. 2. AFTER MOSTLY A LIGHT WIND FLOW TODAY AS SURFACE RIDGE MOVES THROUGH...SOUTHERLY WINDS INCREASE GREATLY TONIGHT...ESPECIALLY FROM 925-850MB. BY 12Z SUNDAY...THEY ARE RUNNING BETWEEN 40-50 KT. 3. 925-850MB TEMPS FOLLOW THE INCREASE IN WINDS. FOR EXAMPLE... 925MB TEMPS AFTER STARTING OFF BETWEEN -2 TO -5C AT 12Z THIS MORNING CLIMB TO 0 TO +3C AT 00Z SUNDAY...THEN TO 2 TO +5C AT 12Z SUNDAY. SUNSHINE SHOULD EASILY BOOST HIGHS INTO THE 40S TODAY AT MOST LOCATIONS...WITH A FEW VALLEY AREAS APPROACHING 50. TEMPERATURES SHOULD BOTTOM OUT THIS EVENING BEFORE THE LOW LEVEL JET INCREASES AND CAUSES THEM TO STABILIZE. READINGS SHOULD RISE LATE TONIGHT AS THE WARMER AIR FLOWS IN. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 328 AM CDT SAT MAR 29 2014 MANY WEATHER CONCERNS TO HIGHLIGHT DURING THE LONG TERM PERIOD AS THE FORECAST AREA LOOKS TO RESIDE MUCH OF THE TIME IN SOUTHWEST FLOW ALOFT. 1. ABOVE NORMAL TEMPERATURES SUNDAY THROUGH MONDAY. THE VIGOROUS SHORTWAVE COMING INTO CALIFORNIA TONIGHT REMAINS ON TRACK TO LIFT INTO EASTERN SOUTH DAKOTA OR SOUTHWEST MN BY 00Z TUESDAY...PUSHING WARM...DOWNSLOPED AIR OFF THE ROCKIES INTO THE FORECAST AREA AHEAD OF IT. 925MB TEMPS ARE PROGGED TO CLIMB TO 9-13C BY 00Z MONDAY...COOLEST OVER TAYLOR/CLARK COUNTIES. THESE READINGS COMBINED WITH SUN THROUGH SCT-BKN CIRRUS AND BREEZY SOUTHERLY WINDS SHOULD PUSH TEMPERATURES INTO THE 60S ALONG/SOUTHWEST OF I-94...WITH 50S TO THE NORTH. A SOUTHERLY BREEZE PERSISTS INTO SUNDAY NIGHT AND MONDAY. THIS WIND SHOULD ONLY ALLOW TEMPERATURES TO FALL INTO THE 40S SUNDAY NIGHT...WITH MAYBE SOME 30S IN THE TYPICAL COLD SPOTS. THEN ON MONDAY...WITH MODEL CONSENSUS KEEPING THE FORECAST AREA IN THE WARM SECTOR HIGHLIGHTED BY 925MB TEMPS OF 9-13C...SHOULD SEE ANOTHER DAY OF HIGHS MOSTLY IN THE MID 50S TO MID 60S. THIS OCCURS DESPITE SOME WARM ADVECTION PRECIPITATION MOVING THROUGH. 2. PRECIPITATION AND THUNDERSTORM POTENTIAL MONDAY INTO MONDAY NIGHT. THE SIGNAL STILL EXISTS FOR A WARM CONVEYOR BELT OF SHOWERS TO MOVE ACROSS THE FORECAST AREA...ESPECIALLY DURING THE LATE MORNING AND AFTERNOON HOURS...AS ISENTROPIC LIFT ON 300K SURFACES AND ABOVE INCREASES. THE BEST MOISTURE EXISTS NORTH OF I- 90...THUS HIGHEST CHANCES OF 50-70 ARE SITUATED THERE. THE POTENTIAL STILL EXISTS FOR A BAND OF SHOWERS AND SOME EMBEDDED THUNDERSTORMS TO FORM ALONG THE COLD FRONT CROSSING LATE IN THE AFTERNOON AND EVENING. HOWEVER...A COUPLE OF CONCERNS FOR THIS BAND INCLUDE MODELS MAY BE OVERDOING THE MOISTURE RETURN AND NOT MIXING DEWPOINTS OUT ENOUGH...AND THE TIME OF DAY IS BEING PUSHED TO OUTSIDE OF PEAK HEATING. SHOULD STORMS FIRE...THERE REMAINS AMPLE SHEAR TO ALLOW FOR SEVERE WEATHER. LASTLY...CONFIDENCE HAS INCREASED THAT THE DEFORMATION BAND ON THE NORTHWEST SIDE OF THE ASSOCIATED SURFACE LOW WILL TRACK NORTHWEST OF THE FORECAST AREA ON MONDAY...AND CLIP THE NORTHWEST HALF OF THE FORECAST AREA MONDAY NIGHT BEFORE LIFTING OFF TO THE NORTHEAST. COLDER AIR RUSHING IN SHOULD ALLOW FOR A CHANGEOVER TO SNOW...WITH A BRIEF PERIOD OF SLEET POSSIBLE DURING THIS CHANGEOVER AS COLD AIR UNDERCUTS WARMER AIR ALOFT. LITTLE SNOW ACCUMULATION IS EXPECTED...THOUGH. THERE IS ALSO POTENTIAL TO LOSE ICE IN THE CLOUDS DUE TO A DRY SLOT...BUT THE LOSS OF ICE OCCURS EITHER WHERE TEMPERATURES ARE ABOVE FREEZING TO RESULT IN RAIN OR WHERE NO PRECIPITATION WILL OCCUR. 3. WINDS MONDAY AFTERNOON AND NIGHT. ECMWF/GFS PROG 925MB WINDS OF 30-40 KT SOUTH OF I-90 DURING THE AFTERNOON. IF MORE SUN OCCURS THAN EXPECTED...THESE COULD EASILY MIX DOWN TO THE SURFACE AND SEE BOTH SUSTAINED WINDS AND GUSTS APPROACH ADVISORY. INCREASED WINDS AND GUSTS AS A RESULT. ALSO...AS THE LOW PASSES TO OUR NORTHEAST...A TIGHT PRESSURE GRADIENT WITH 925MB WINDS OF 30-40 KT FROM THE SOUTHWEST TO WEST USHERS IN COLD AIR. WITH SOME ISALLOBARIC AID...COULD SEE GUSTS HERE TOO APPROACH ADVISORY FOR A BRIEF TIME. 4. WINTRY MIX POTENTIAL LATE TUESDAY NIGHT THROUGH FRIDAY. MODELS ARE AT ODDS ON HOW TO HANDLE THE EJECTION OF TROUGHING OUT OF THE SOUTHWESTERN U.S. ON TUESDAY TOWARDS THE REGION LATER IN THE WEEK. THERE WILL NO DOUBT BE A COLDER DOME OF HIGH PRESSURE INFLUENCING THE AREA...LIKELY SITUATED FROM NORTHERN MN INTO UPPER MI. IN ADDITION...AS THE TROUGH EJECTS...ISENTROPIC LIFT OF WARMER...GULF OF MEXICO MOISTURE WILL SPREAD PRECIPITATION NORTH TOWARDS THE FORECAST AREA. THIS SETS UP CONCERN FOR THE WINTRY MIX. FOR NOW HAVE FOLLOWED A MODEL CONSENSUS WITH PRECIPITATION CHANCES...WHICH SEEMS MOST LIKELY TO OCCUR WEDNESDAY SOUTH OF I-90. ALSO KEPT TYPES AS RAIN/SNOW BASED ON HOURLY TEMPERATURES...BUT THERE IS DEFINITELY POTENTIAL FOR SLEET AND FREEZING RAIN/DRIZZLE AT TIMES. 29.00Z ECMWF EVEN PRODUCES AT LEAST ADVISORY WORTHY SNOWFALL OVER THE NORTHWEST HALF OF THE AREA THURSDAY AND THURSDAY NIGHT. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 709 AM CDT SAT MAR 29 2014 VFR CONDITIONS ARE EXPECTED AT THE TAF SITES TODAY AS HIGH PRESSURE BUILDS IN FROM THE NORTHERN PLAINS. A STRONG LOW PRESSURE SYSTEM WILL DEVELOP OVER THE CENTRAL PLAINS TONIGHT CREATING A TIGHT PRESSURE GRADIENT OVER THE UPPER MISSISSIPPI RIVER VALLEY. SOUTH WINDS WILL INCREASE TO AROUND 17 KTS AT KRST AND INTO THE 10 TO 12 KT RANGE AT LSE. ALSO...WINDS INCREASE TO 45 TO 50 KTS IN THE 1500 TO 2000 FT LAYER LEADING TO LOW LEVEL WIND SHEAR CONCERNS MAINLY AFTER 10Z. HAVE INCLUDED LOW LEVEL WIND SHEAR IN THE KRST TAF STARTING AT 09Z. CONFIDENCE NOT AS HIGH AT KLSE ON THE WINDS ABOVE THE SURFACE BEING STRONG ENOUGH LLWS PRIOR TO 12Z SO HAVE NOT INCLUDED IT IN THE TAF AT THIS TIME. && .HYDROLOGY... ISSUED AT 328 AM CDT SAT MAR 29 2014 MAIN FOCUS FOR RIVER ISSUES FROM THE RECENT RAIN IS ON THE KICKAPOO RIVER. SOME LOCATIONS ALONG IT ARE EITHER IN OR EXPECTED TO REACH FLOOD STAGE AS RUNOFF CONTINUES TO WORK ITS WAY DOWNSTREAM. FROM SUNDAY INTO MONDAY NIGHT...THE RAPID WARM UP WILL CAUSE THE SNOW PACK NORTH OF INTERSTATE 94 TO MELT RAPIDLY. IN ADDITION WITH FROZEN GROUND...ANY RAINFALL ON MONDAY AND MONDAY NIGHT WILL QUICKLY RUNOFF INTO AREA RIVERS AND STREAMS. THIS WILL RESULT IN RISES ALONG THE BLACK...BUFFALO...AND TREMPEALEAU RIVERS IN WESTERN WISCONSIN. SOME FLOODING IS ALSO A POSSIBILITY. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...AJ LONG TERM...AJ AVIATION...WETENKAMP HYDROLOGY...AJ
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
328 AM CDT SAT MAR 29 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 328 AM CDT SAT MAR 29 2014 CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS SHOWED A VERY DEEP TROUGH OFF THE PACIFIC NORTHWEST...RIDGING PUSHING EASTWARD ACROSS THE ROCKIES...AND TROUGHING FROM MINNESOTA SOUTH INTO ARKANSAS. THE NORTHERN PORTION OF THIS TROUGH HAS BEEN UNEVENTFUL FOR THE FORECAST AREA...BRINGING ONLY SOME MID/HIGH CLOUDS. DRY AIR SITUATED BETWEEN 900-700MB ON THE 00Z GRB...MPX AND DVN SOUNDINGS KEPT ANY POTENTIAL PRECIPITATION FROM THESE CLOUDS FROM REACHING THE GROUND. HOWEVER...AT AND BELOW 900MB... OBSERVATIONS ARE SHOWING SOME LOW STRATUS DEVELOPING ACROSS SOUTHERN WI. THIS STRATUS IS A RESULT OF EASTERLY FLOW OF MOISTURE FROM LAKE MICHIGAN COMBINING WITH NOCTURNAL COOLING AND AN INVERTED SURFACE TROUGH IN THE AREA. TO THE NORTHWEST...CLEARING ASSOCIATED WITH SURFACE HIGH PRESSURE WAS PRESENT ACROSS MUCH OF MINNESOTA. AIRMASS OVER THE UPPER MIDWEST STILL RELATIVELY COOL WITH 00Z RAOBS SHOWING 925MB TEMPS OF -3 TO -5C FROM THE FORECAST AREA TO BIS. HOWEVER...LBF AND UNR ON THE BACK SIDE OF THE SURFACE HIGH WERE MUCH WARMER AT +11 AND +15C RESPECTIVELY. A PROGRESSIVE UPPER FLOW PATTERN IS PROGGED THROUGH THE SHORT TERM PERIOD AS A VIGOROUS SHORTWAVE AT THE BOTTOM OF THE EAST PACIFIC TROUGH...NEAR 35 NORTH / 140 WEST...MOVES INTO CALIFORNIA. FOR COMPARISON...THE FORECAST AREA GOES FROM UNDER A SHORTWAVE TROUGH AXIS AT 12Z SATURDAY TO A RIDGE AXIS AT 12Z SUNDAY. 3 MAIN IMPACTS FROM THIS SWITCH: 1. SUBSIDENCE AND DRYING ASSOCIATED WITH BUILDING UPPER RIDGING WILL HELP CLEAR OUT ANY LOW CLOUDS BY 18Z...LEADING TO A SUNNY AFTERNOON WITH JUST SOME SCATTERED CIRRUS TONIGHT. 2. AFTER MOSTLY A LIGHT WIND FLOW TODAY AS SURFACE RIDGE MOVES THROUGH...SOUTHERLY WINDS INCREASE GREATLY TONIGHT...ESPECIALLY FROM 925-850MB. BY 12Z SUNDAY...THEY ARE RUNNING BETWEEN 40-50 KT. 3. 925-850MB TEMPS FOLLOW THE INCREASE IN WINDS. FOR EXAMPLE... 925MB TEMPS AFTER STARTING OFF BETWEEN -2 TO -5C AT 12Z THIS MORNING CLIMB TO 0 TO +3C AT 00Z SUNDAY...THEN TO 2 TO +5C AT 12Z SUNDAY. SUNSHINE SHOULD EASILY BOOST HIGHS INTO THE 40S TODAY AT MOST LOCATIONS...WITH A FEW VALLEY AREAS APPROACHING 50. TEMPERATURES SHOULD BOTTOM OUT THIS EVENING BEFORE THE LOW LEVEL JET INCREASES AND CAUSES THEM TO STABILIZE. READINGS SHOULD RISE LATE TONIGHT AS THE WARMER AIR FLOWS IN. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 328 AM CDT SAT MAR 29 2014 MANY WEATHER CONCERNS TO HIGHLIGHT DURING THE LONG TERM PERIOD AS THE FORECAST AREA LOOKS TO RESIDE MUCH OF THE TIME IN SOUTHWEST FLOW ALOFT. 1. ABOVE NORMAL TEMPERATURES SUNDAY THROUGH MONDAY. THE VIGOROUS SHORTWAVE COMING INTO CALIFORNIA TONIGHT REMAINS ON TRACK TO LIFT INTO EASTERN SOUTH DAKOTA OR SOUTHWEST MN BY 00Z TUESDAY...PUSHING WARM...DOWNSLOPED AIR OFF THE ROCKIES INTO THE FORECAST AREA AHEAD OF IT. 925MB TEMPS ARE PROGGED TO CLIMB TO 9-13C BY 00Z MONDAY...COOLEST OVER TAYLOR/CLARK COUNTIES. THESE READINGS COMBINED WITH SUN THROUGH SCT-BKN CIRRUS AND BREEZY SOUTHERLY WINDS SHOULD PUSH TEMPERATURES INTO THE 60S ALONG/SOUTHWEST OF I-94...WITH 50S TO THE NORTH. A SOUTHERLY BREEZE PERSISTS INTO SUNDAY NIGHT AND MONDAY. THIS WIND SHOULD ONLY ALLOW TEMPERATURES TO FALL INTO THE 40S SUNDAY NIGHT...WITH MAYBE SOME 30S IN THE TYPICAL COLD SPOTS. THEN ON MONDAY...WITH MODEL CONSENSUS KEEPING THE FORECAST AREA IN THE WARM SECTOR HIGHLIGHTED BY 925MB TEMPS OF 9-13C...SHOULD SEE ANOTHER DAY OF HIGHS MOSTLY IN THE MID 50S TO MID 60S. THIS OCCURS DESPITE SOME WARM ADVECTION PRECIPITATION MOVING THROUGH. 2. PRECIPITATION AND THUNDERSTORM POTENTIAL MONDAY INTO MONDAY NIGHT. THE SIGNAL STILL EXISTS FOR A WARM CONVEYOR BELT OF SHOWERS TO MOVE ACROSS THE FORECAST AREA...ESPECIALLY DURING THE LATE MORNING AND AFTERNOON HOURS...AS ISENTROPIC LIFT ON 300K SURFACES AND ABOVE INCREASES. THE BEST MOISTURE EXISTS NORTH OF I- 90...THUS HIGHEST CHANCES OF 50-70 ARE SITUATED THERE. THE POTENTIAL STILL EXISTS FOR A BAND OF SHOWERS AND SOME EMBEDDED THUNDERSTORMS TO FORM ALONG THE COLD FRONT CROSSING LATE IN THE AFTERNOON AND EVENING. HOWEVER...A COUPLE OF CONCERNS FOR THIS BAND INCLUDE MODELS MAY BE OVERDOING THE MOISTURE RETURN AND NOT MIXING DEWPOINTS OUT ENOUGH...AND THE TIME OF DAY IS BEING PUSHED TO OUTSIDE OF PEAK HEATING. SHOULD STORMS FIRE...THERE REMAINS AMPLE SHEAR TO ALLOW FOR SEVERE WEATHER. LASTLY...CONFIDENCE HAS INCREASED THAT THE DEFORMATION BAND ON THE NORTHWEST SIDE OF THE ASSOCIATED SURFACE LOW WILL TRACK NORTHWEST OF THE FORECAST AREA ON MONDAY...AND CLIP THE NORTHWEST HALF OF THE FORECAST AREA MONDAY NIGHT BEFORE LIFTING OFF TO THE NORTHEAST. COLDER AIR RUSHING IN SHOULD ALLOW FOR A CHANGEOVER TO SNOW...WITH A BRIEF PERIOD OF SLEET POSSIBLE DURING THIS CHANGEOVER AS COLD AIR UNDERCUTS WARMER AIR ALOFT. LITTLE SNOW ACCUMULATION IS EXPECTED...THOUGH. THERE IS ALSO POTENTIAL TO LOSE ICE IN THE CLOUDS DUE TO A DRY SLOT...BUT THE LOSS OF ICE OCCURS EITHER WHERE TEMPERATURES ARE ABOVE FREEZING TO RESULT IN RAIN OR WHERE NO PRECIPITATION WILL OCCUR. 3. WINDS MONDAY AFTERNOON AND NIGHT. ECMWF/GFS PROG 925MB WINDS OF 30-40 KT SOUTH OF I-90 DURING THE AFTERNOON. IF MORE SUN OCCURS THAN EXPECTED...THESE COULD EASILY MIX DOWN TO THE SURFACE AND SEE BOTH SUSTAINED WINDS AND GUSTS APPROACH ADVISORY. INCREASED WINDS AND GUSTS AS A RESULT. ALSO...AS THE LOW PASSES TO OUR NORTHEAST...A TIGHT PRESSURE GRADIENT WITH 925MB WINDS OF 30-40 KT FROM THE SOUTHWEST TO WEST USHERS IN COLD AIR. WITH SOME ISALLOBARIC AID...COULD SEE GUSTS HERE TOO APPROACH ADVISORY FOR A BRIEF TIME. 4. WINTRY MIX POTENTIAL LATE TUESDAY NIGHT THROUGH FRIDAY. MODELS ARE AT ODDS ON HOW TO HANDLE THE EJECTION OF TROUGHING OUT OF THE SOUTHWESTERN U.S. ON TUESDAY TOWARDS THE REGION LATER IN THE WEEK. THERE WILL NO DOUBT BE A COLDER DOME OF HIGH PRESSURE INFLUENCING THE AREA...LIKELY SITUATED FROM NORTHERN MN INTO UPPER MI. IN ADDITION...AS THE TROUGH EJECTS...ISENTROPIC LIFT OF WARMER...GULF OF MEXICO MOISTURE WILL SPREAD PRECIPITATION NORTH TOWARDS THE FORECAST AREA. THIS SETS UP CONCERN FOR THE WINTRY MIX. FOR NOW HAVE FOLLOWED A MODEL CONSENSUS WITH PRECIPITATION CHANCES...WHICH SEEMS MOST LIKELY TO OCCUR WEDNESDAY SOUTH OF I-90. ALSO KEPT TYPES AS RAIN/SNOW BASED ON HOURLY TEMPERATURES...BUT THERE IS DEFINITELY POTENTIAL FOR SLEET AND FREEZING RAIN/DRIZZLE AT TIMES. 29.00Z ECMWF EVEN PRODUCES AT LEAST ADVISORY WORTHY SNOWFALL OVER THE NORTHWEST HALF OF THE AREA THURSDAY AND THURSDAY NIGHT. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 1137 PM CDT FRI MAR 28 2014 MID-LEVEL TROUGH CONTINUES TO MOVE EAST ACROSS THE AREA WITH THE BACK EDGE OF VFR/MID CLOUDS APPROACHING SOUTHEAST MN. STILL THINKING MID CLOUD WILL SCATTER OUT AT KRST BY 06Z AND AT KLSE BY 08Z. FOCUS THEN TURNS TO MVFR STRATUS ACROSS SOUTHERN WI THAT WILL BE ADVECTING WESTWARD TOWARD THE KLSE TAF SITE AROUND THE SAME TIME THE MID CLOUDS SCATTERS. THIS IS IN RESPONSE TO AN EASTERLY FLOW OFF LAKE MICHIGAN AND AN INVERTED SURFACE TROUGH SETTING UP JUST EAST OF THE MISSISSIPPI RIVER. RAP/NAM MODELS CONTINUE TO STOP THIS STRATUS JUST SHY OF THE KLSE TAF SITE...KEEP IT ACROSS SOUTHEAST LA CROSSE COUNTY/WESTERN MONROE COUNTY. WILL CONTINUE TO HONOR THIS SIGNAL AND CARRY A SCT025 SKY CONDITION AT KLSE AFTER 08Z. WILL CONTINUE TO MONITOR THIS MVFR CLOUD CLOSELY. EXPECTING STRATUS TO ERODE TO THE SOUTHEAST SATURDAY MORNING WITH HIGHS PRESSURE RIDGE BUILDING IN. SKC/VFR CONDITIONS THEN EXPECTED THROUGH THE REST OF THE DAY WITH LIGHT/VARIABLE WINDS...TURNING LIGHT SOUTHEAST THROUGH THE AFTERNOON HOURS. PLAN ON SOME SCATTERED CIRRUS TO MOVE INTO THE AREA SATURDAY EVENING AHEAD OF A WARM FRONT MOVING THROUGH THE NORTHERN PLAINS/NORTHERN MN WITH WINDS PICKING UP OUT OF THE SOUTHEAST THROUGH THE NIGHT. && .HYDROLOGY... ISSUED AT 328 AM CDT SAT MAR 29 2014 MAIN FOCUS FOR RIVER ISSUES FROM THE RECENT RAIN IS ON THE KICKAPOO RIVER. SOME LOCATIONS ALONG IT ARE EITHER IN OR EXPECTED TO REACH FLOOD STAGE AS RUNOFF CONTINUES TO WORK ITS WAY DOWNSTREAM. FROM SUNDAY INTO MONDAY NIGHT...THE RAPID WARM UP WILL CAUSE THE SNOW PACK NORTH OF INTERSTATE 94 TO MELT RAPIDLY. IN ADDITION WITH FROZEN GROUND...ANY RAINFALL ON MONDAY AND MONDAY NIGHT WILL QUICKLY RUNOFF INTO AREA RIVERS AND STREAMS. THIS WILL RESULT IN RISES ALONG THE BLACK...BUFFALO...AND TREMPEALEAU RIVERS IN WESTERN WISCONSIN. SOME FLOODING IS ALSO A POSSIBILITY. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...AJ LONG TERM...AJ AVIATION...DAS HYDROLOGY...AJ
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1131 AM MDT SAT MAR 29 2014 .UPDATE... ISSUED AT 901 AM MDT SAT MAR 29 2014 WILL HAVE TO KEEP A CLOSE EYE ON WIND SPEEDS IN THE ARLINGTON AREA TODAY. WINDS HAVE GUSTED AS HIGH AS 57 MPH AT THE ARLINGTON WY DOT SITE WITH OTHER SITES GUSTING 50 TO 55 MPH. MODELS DO SHOWING WINDS ALOFT INCREASING SLIGHTLY THIS AFTERNOON BUT NOT AS STRONG OF SUBSIDENCE. AT THIS TIME WILL HOLD OFF ON ANY HEADLINES AS WINDS SHOULD BE MARGINAL FOR A HIGH WIND WARNING AND RELATIVELY LOCALIZED. UPDATED THE SKY GRIDS AS THE STANDING WAVE CLOUDS IS IN PLACE ALONG AND EAST OF THE LARAMIE RANGE. MODELS INDICATE THE WAVE COULD WILL THIN OUT THIS AFTERNOON. SHOULD NOT SEE A BIG IMPACT ON TEMPERATURES TODAY BUT IT WILL BE A SLOWER RISE IN TEMPERATURES AND COULD END UP A FEW DEGREES BELOW THE CURRENT FORECAST WHERE THE WAVE CLOUD HANGS ON THE LONGEST. OTHERWISE FORECAST IN GOOD SHAPE. && .SHORT TERM...(TODAY AND TONIGHT) MAIN WEATHER STORIES THROUGH THIS EVENING WILL BE THE WARM TEMPERATURES AND ASSOCIATED FIRE WEATHER CONCERNS AND THE WINDY CONDITIONS ALONG AND WEST OF THE LARAMIE RANGE. HIGHS THIS AFTN ARE STILL EXPECTED TO CLIMB INTO THE 60S AND LOWER 70S ACROSS THE PLAINS. MAIN CHANGE TO THE FCST GRIDS FOR THIS AFTN WAS TO DECREASE DEW POINTS...ESPECIALLY STRETCHING FROM LARAMIE COUNTY INTO THE SOUTHERN PANHANDLE. DEEP SOUTHWESTERLY FLOW IN THE LOW-TO-MID LEVELS WILL COMBINE WITH EXCELLENT SOLAR INSULATION TO PRODUCE DEEP LLVL MIXING THIS AFTN AND IT IS THESE CONDITIONS THAT MOS OFTEN GROSSLY UNDERESTIMATES AFTN DEW POINTS. WENT WITH A BLEND OF THE DRIER MAV AND RUC GUIDANCE AND THIS RESULTS IN MIN RH VALUES IN THE 10-15 PERCENT RANGE OVER THE PANHANDLE. EXCELLENT MIXING WILL TAP INTO 25-30 KT AT THE TOP OF THE MIXED LAYER. THUS...DECIDED TO ISSUE A RFW FOR THE ENTIRE PANHANDLE. THE NEXT ITEM OF CONCERN IS WINDS TO THE WEST OF THE LARAMIE RANGE. THE GFS SHOWS 700MB WINDS OF 40-45 KT FROM 18-00Z AND THE 700MB CAG-CPR GRADIENT IS AROUND 45 METERS. CONTEMPLATED PUTTING THE ARLINGTON AREA IN A HIGH WIND WARNING FOR THE AFTN...HOWEVER WOULD LIKE TO SEE THE LLVL GRADIENT AND WINDS ALOFT A BIT STRONGER. WILL LIKELY SEE GUSTS AROUND 45 KT IN THE ARLINGTON AREA WITH THE FAVORABLE GAP WINDS. OUTSIDE OF ARLINGTON...COULD SEE GUSTS TO 40 KT DURING PEAK MIXING. THE LLVL GRADIENT COMES DOWN BY THIS EVENING AND FLOW ALOFT BECOMES MORE SOUTHWESTERLY...SO WILL SEE WINDS DECREASE. ANOTHER WARM DAY ON SUNDAY AHEAD OF A SHORTWAVE. KEPT A SLIGHT CHANCE OF AFTN TSTMS IN THE FCST AS BOTH THE GFS AND NAM INDICATE LIFTED INDICES OF 0C TO -1C. MODELS CONTINUE TO INDICATE THAT THE UPPER LEVEL SYSTEM WILL MOVE DIRECTLY OVERHEAD ON SUNDAY NIGHT WITH A FROPA AFTER 06Z MON. BEST UPPER LEVEL DIVERGENCE AND LARGE SCALE LIFT IS LARGELY OFF TO THE NORTHEAST OF THE CWA...HOWEVER MAY HAVE TO WATCH THE NORTHEAST ZONES FOR ADVISORY AMOUNTS. THIS AREA WILL BE CLOSEST TO THE WESTERN EDGE OF A DEVELOPING TROWAL/FRONTOGENESIS FEATURE OVER SOUTH DAKOTA. JUST SOMETHING TO WATCH IN FUTURE MODEL RUNS. .LONG TERM...(EARLY TUESDAY MORNING THROUGH FRIDAY) ISSUED AT 445 AM MDT SAT MAR 29 2014 MAIN FORECAST CONCERN NEXT WEEK WILL BE A SLOW MOVING UPPER LEVEL LOW MOVING ACROSS THE GREAT BASIN REGION AND INTO THE ROCKY MOUNTAINS BY WEDNESDAY. ALTHOUGH MODELS ARE IN POOR AGREEMENT WITH THIS SYSTEM AND HAVE BEEN OVER THE LAST 48 HOURS...THERE IS STILL CONCERN OVER A POTENTIAL SIGNIFICANT STORM OVER PORTIONS OF THE HIGH PLAINS. FOR TUESDAY...ALL MODELS NOW SHOW THE COLD FRONT FROM SUNDAYS SYSTEM ALONG THE CONTINENTAL DIVIDE...RETREATING EASTWARD AS A WARM FRONT. WARM AIR ADVECTION ALOFT AND COOL UPSLOPE FLOW WILL COMBINE TO PRODUCE OVERRUNNING PRECIPITATION IN THE FORM OF SNOW ACROSS THE FORECAST AREA. INCREASED POP BETWEEN 30 TO 50 PERCENT ACROSS MOST OF THE FORECAST AREA WITH THE EXCEPTION OF EXTREME EASTERN ZONES ACROSS THE SOUTHERN NEBRASKA PANHANDLE. 1 TO 2 INCHES OF SNOW LOOKS POSSIBLE WITH THIS INITIAL OVERRUNNING EVENT TUESDAY...ESPECIALLY NORTH OF I80. AS THE WARM FRONT LIFTS NORTHEAST DURING THE DAY...THE SNOW WILL QUICKLY MELT AND/OR CHANGE TO RAIN AS TEMPERATURES INCREASE INTO THE 50S. ATTENTION THEN SHIFTS WESTWARD TUESDAY NIGHT AS THE MAIN UPPER LEVEL LOW MOVES ACROSS THE GREAT BASIN. MODELS ARE STRUGGLING WITH THE PLACEMENT...MOVEMENT...AND POTENTIAL EVOLUTION OF A STRONG WINTER STORM. ALL MODELS INDICATE A BRIEF BREAK EARLY WEDNESDAY BEFORE THE UPPER LEVEL LOW MOVES INTO THE ROCKY MOUNTAIN REGION AND ATTEMPTS TO BECOME BETTER ORGANIZED. THE ECMWF SHOWS A RATHER DISORGANIZED STORM SYSTEM...WITH THE MAIN LOW EJECTING NORTHEAST AND THEN DRIFTING EASTWARD INTO THE DAKOTAS...WHILE THE SOUTHERN ENERGY PUSHES INTO THE GREAT PLAINS AND THEN INITIATES STRONG CYCLOGENESIS IN KANSAS/MISSOURI LATE WEDNESDAY NIGHT. THE ECMWF INDICATES SPLIT FLOW ACROSS SOUTHEAST WYOMING WITH LIGHT SNOW ACCUMULATIONS NEAR I80 DUE TO THE SOUTHERN WAVE...AND LIGHT SNOW ACROSS CENTRAL WYOMING DUE TO THE MAIN LOW WITH LITTLE IN BETWEEN. THE GEM IS THE MOST AGGRESSIVE...SHOWING A COLORADO LOW SLOWLY EJECTING NORTHEAST FROM THE FOUR CORNERS REGION. THIS SCENARIO RESULTS IN WIDESPREAD MODERATE TO HEAVY SNOWFALL ACROSS THE FORECAST AREA BEGINNING WEDNESDAY EVENING AND LASTING THROUGH THURSDAY. THE 00Z GFS WAS CONSIDERABLY FURTHER SOUTH...WITH THE I80 CORRIDOR GETTING CLIPPED BY LIGHT SNOWFALL. HOWEVER...THE 06Z GFS IS FURTHER NORTH CLOSER TO THE GEM. MOST OF THE ENSEMBLE FORECASTS WERE IN BETWEEN THE GEM AND GFS LAST NIGHT...SO KEPT POP BETWEEN 25 TO 40 PERCENT OVER THE LOWER ELEVATIONS WITH POP NEAR 70 PERCENT IN THE MOUNTAINS THROUGH THURSDAY EVENING. WILL CONTINUE TO CLOSELY MONITOR THIS SYSTEM THROUGH THIS WEEKEND AND EARLY NEXT WEEK FOR CHANGES...BUT A SIGNIFICANT STORM SYSTEM APPEARS POSSIBLE NEXT WEEK. LOWERED TEMPERATURES BELOW NORMAL WEDNESDAY THROUGH FRIDAY. A WEAK RIDGE OF HIGH PRESSURE WILL BUILD ACROSS THE AREA ON FRIDAY...WITH DRIER CONDITIONS EXPECTED. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY MORNING) ISSUED AT 1130 AM MDT SAT MAR 29 2014 CONSIDERABLE MAINLY HIGH LEVEL CLOUDINESS WILL PRODUCE VFR CEILINGS THROUGH TONIGHT. GUSTY SOUTHWESTERLY SURFACE WINDS WILL PREVAIL THIS AFTERNOON AND EVENING...WITH THE STRONGER GUSTS /30-40 KT/ EXPECTED OVER SOUTHEAST AND SOUTH CENTRAL WYOMING. && .FIRE WEATHER... ISSUED AT 414 AM MDT SAT MAR 29 2014 A WARM AND DRY AIRMASS WILL BE IN PLACE OVER THE REGION THROUGH THE WEEKEND. HIGHS WILL BE 10-15 DEGREES ABOVE NORMAL. MINIMUM HUMIDITY VALUES WILL FALL INTO THE 10-15 PERCENT RANGE OVER THE NEBRASKA PANHANDLE THIS AFTERNOON AND WILL COMBINE WITH GUSTY SOUTHWEST WINDS TO PRODUCE CRITICAL FIRE WEATHER CONDITIONS. A RED FLAG WARNING IS IN EFFECT THIS AFTERNOON FOR THE PANHANDLE SINCE FUELS ARE CONDUCIVE TO FIRE GROWTH IN THAT REGION. WHILE HUMIDITY VALUES WILL BE SIMILAR ON SUNDAY AFTERNOON...WIND SPEEDS SHOULD BE LESS SO ONLY AN ELEVATED FIRE WEATHER THREAT IS EXPECTED. COOLER TEMPERATURES WILL OCCUR ON MONDAY BEHIND A COLD FRONT THAT WILL PASS OVER THE REGION ON SUNDAY NIGHT. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...HIGH WIND WARNING UNTIL 10 PM MDT THIS EVENING FOR WYZ110. NE...RED FLAG WARNING UNTIL 7 PM MDT THIS EVENING FOR NEZ311>313. && $$ UPDATE...SML SHORT TERM...FINCH LONG TERM...TJT AVIATION...JAMSKI FIRE WEATHER...FINCH
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
914 AM MDT SAT MAR 29 2014 .UPDATE... ISSUED AT 901 AM MDT SAT MAR 29 2014 WILL HAVE TO KEEP A CLOSE EYE ON WIND SPEEDS IN THE ARLINGTON AREA TODAY. WINDS HAVE GUSTED AS HIGH AS 57 MPH AT THE ARLINGTON WY DOT SITE WITH OTHER SITES GUSTING 50 TO 55 MPH. MODELS DO SHOWING WINDS ALOFT INCREASING SLIGHTLY THIS AFTERNOON BUT NOT AS STRONG OF SUBSIDENCE. AT THIS TIME WILL HOLD OFF ON ANY HEADLINES AS WINDS SHOULD BE MARGINAL FOR A HIGH WIND WARNING AND RELATIVELY LOCALIZED. UPDATED THE SKY GRIDS AS THE STANDING WAVE CLOUDS IS IN PLACE ALONG AND EAST OF THE LARAMIE RANGE. MODELS INDICATE THE WAVE COULD WILL THIN OUT THIS AFTERNOON. SHOULD NOT SEE A BIG IMPACT ON TEMPERATURES TODAY BUT IT WILL BE A SLOWER RISE IN TEMPERATURES AND COULD END UP A FEW DEGREES BELOW THE CURRENT FORECAST WHERE THE WAVE CLOUD HANGS ON THE LONGEST. OTHERWISE FORECAST IN GOOD SHAPE. && .SHORT TERM...(TODAY AND TONIGHT) MAIN WEATHER STORIES THROUGH THIS EVENING WILL BE THE WARM TEMPERATURES AND ASSOCIATED FIRE WEATHER CONCERNS AND THE WINDY CONDITIONS ALONG AND WEST OF THE LARAMIE RANGE. HIGHS THIS AFTN ARE STILL EXPECTED TO CLIMB INTO THE 60S AND LOWER 70S ACROSS THE PLAINS. MAIN CHANGE TO THE FCST GRIDS FOR THIS AFTN WAS TO DECREASE DEWPOINTS...ESPECIALLY STRETCHING FROM LARAMIE COUNTY INTO THE SOUTHERN PANHANDLE. DEEP SOUTHWESTERLY FLOW IN THE LOW-TO-MIDLEVELS WILL COMBINE WITH EXCELLENT SOLAR INSULATION TO PRODUCE DEEP LLVL MIXING THIS AFTN AND IT IS THESE CONDITIONS THAT MOS OFTEN GROSSLY UNDERESTIMATES AFTN DEWPOINTS. WENT WITH A BLEND OF THE DRIER MAV AND RUC GUIDANCE AND THIS RESULTS IN MIN RH VALUES IN THE 10-15 PERCENT RANGE OVER THE PANHANDLE. EXCELLENT MIXING WILL TAP INTO 25-30 KTS AT THE TOP OF THE MIXED LAYER. THUS...DECIDED TO ISSUE A RFW FOR THE ENTIRE PANHANDLE. THE NEXT ITEM OF CONCERN IS WINDS TO THE WEST OF THE LARAMIE RANGE. THE GFS SHOWS 700MB WINDS OF 40-45 KTS FROM 18-00Z AND THE 700MB CAG-CPR GRADIENT IS AROUND 45 METERS. CONTEMPLATED PUTTING THE ARLINGTON AREA IN A HIGH WIND WARNING FOR THE AFTN...HOWEVER WOULD LIKE TO SEE THE LLVL GRADIENT AND WINDS ALOFT A BIT STRONGER. WILL LIKELY SEE GUSTS AROUND 45 KTS IN THE ARLINGTON AREA WITH THE FAVORABLE GAP WINDS. OUTSIDE OF ARLINGTON...COULD SEE GUSTS TO 40 KTS DURING PEAK MIXING. THE LLVL GRADIENT COMES DOWN BY THIS EVENING AND FLOW ALOFT BECOMES MORE SOUTHWESTERLY...SO WILL SEE WINDS DECREASE. ANOTHER WARM DAY ON SUNDAY AHEAD OF A SHORTWAVE. KEPT A SLIGHT CHANCE OF AFTN TSTMS IN THE FCST AS BOTH THE GFS AND NAM INDICATE LIFTED INDICES OF 0C TO -1C. MODELS CONTINUE TO INDICATE THAT THE UPPER LEVEL SYSTEM WILL MOVE DIRECTLY OVERHEAD ON SUNDAY NIGHT WITH A FROPA AFTER 06Z MON. BEST UPPER LEVEL DIVERGENCE AND LARGE SCALE LIFT IS LARGELY OFF TO THE NORTHEAST OF THE CWA...HOWEVER MAY HAVE TO WATCH THE NORTHEAST ZONES FOR ADVISORY AMOUNTS. THIS AREA WILL BE CLOSEST TO THE WESTERN EDGE OF A DEVELOPING TROWAL/FRONTOGENESIS FEATURE OVER SOUTH DAKOTA. JUST SOMETHING TO WATCH IN FUTURE MODEL RUNS. .LONG TERM...(EARLY TUESDAY MORNING THROUGH FRIDAY) ISSUED AT 445 AM MDT SAT MAR 29 2014 MAIN FORECAST CONCERN NEXT WEEK WILL BE A SLOW MOVING UPPER LEVEL LOW MOVING ACROSS THE GREAT BASIN REGION AND INTO THE ROCKY MOUNTAINS BY WEDNESDAY. ALTHOUGH MODELS ARE IN POOR AGREEMENT WITH THIS SYSTEM AND HAVE BEEN OVER THE LAST 48 HOURS...THERE IS STILL CONCERN OVER A POTENTIAL SIGNIFICANT STORM OVER PORTIONS OF THE HIGH PLAINS. FOR TUESDAY...ALL MODELS NOW SHOW THE COLD FRONT FROM SUNDAYS SYSTEM ALONG THE CONTINENTAL DIVIDE...RETREATING EASTWARD AS A WARM FRONT. WARM AIR ADVECTION ALOFT AND COOL UPSLOPE FLOW WILL COMBINE TO PRODUCE OVERRUNNING PRECIPITATION IN THE FORM OF SNOW ACROSS THE FORECAST AREA. INCREASED POP BETWEEN 30 TO 50 PERCENT ACROSS MOST OF THE FORECAST AREA WITH THE EXCEPTION OF EXTREME EASTERN ZONES ACROSS THE SOUTHERN NEBRASKA PANHANDLE. 1 TO 2 INCHES OF SNOW LOOKS POSSIBLE WITH THIS INITIAL OVERRUNNING EVENT TUESDAY...ESPECIALLY NORTH OF I80. AS THE WARM FRONT LIFTS NORTHEAST DURING THE DAY...THE SNOW WILL QUICKLY MELT AND/OR CHANGE TO RAIN AS TEMPERATURES INCREASE INTO THE 50S. ATTENTION THEN SHIFTS WESTWARD TUESDAY NIGHT AS THE MAIN UPPER LEVEL LOW MOVES ACROSS THE GREAT BASIN. MODELS ARE STRUGGLING WITH THE PLACEMENT...MOVEMENT...AND POTENTIAL EVOLUTION OF A STRONG WINTER STORM. ALL MODELS INDICATE A BRIEF BREAK EARLY WEDNESDAY BEFORE THE UPPER LEVEL LOW MOVES INTO THE ROCKY MOUNTAIN REGION AND ATTEMPTS TO BECOME BETTER ORGANIZED. THE ECMWF SHOWS A RATHER DISORGANIZED STORM SYSTEM...WITH THE MAIN LOW EJECTING NORTHEAST AND THEN DRIFTING EASTWARD INTO THE DAKOTAS...WHILE THE SOUTHERN ENERGY PUSHES INTO THE GREAT PLAINS AND THEN INITIATES STRONG CYCLOGENESIS IN KANSAS/MISSOURI LATE WEDNESDAY NIGHT. THE ECMWF INDICATES SPLIT FLOW ACROSS SOUTHEAST WYOMING WITH LIGHT SNOW ACCUMULATIONS NEAR I80 DUE TO THE SOUTHERN WAVE...AND LIGHT SNOW ACROSS CENTRAL WYOMING DUE TO THE MAIN LOW WITH LITTLE IN BETWEEN. THE GEM IS THE MOST AGGRESSIVE...SHOWING A COLORADO LOW SLOWLY EJECTING NORTHEAST FROM THE FOUR CORNERS REGION. THIS SCENARIO RESULTS IN WIDESPREAD MODERATE TO HEAVY SNOWFALL ACROSS THE FORECAST AREA BEGINNING WEDNESDAY EVENING AND LASTING THROUGH THURSDAY. THE 00Z GFS WAS CONSIDERABLY FURTHER SOUTH...WITH THE I80 CORRIDOR GETTING CLIPPED BY LIGHT SNOWFALL. HOWEVER...THE 06Z GFS IS FURTHER NORTH CLOSER TO THE GEM. MOST OF THE ENSEMBLE FORECASTS WERE IN BETWEEN THE GEM AND GFS LAST NIGHT...SO KEPT POP BETWEEN 25 TO 40 PERCENT OVER THE LOWER ELEVATIONS WITH POP NEAR 70 PERCENT IN THE MOUNTAINS THROUGH THURSDAY EVENING. WILL CONTINUE TO CLOSELY MONITOR THIS SYSTEM THROUGH THIS WEEKEND AND EARLY NEXT WEEK FOR CHANGES...BUT A SIGNIFICANT STORM SYSTEM APPEARS POSSIBLE NEXT WEEK. LOWERED TEMPERATURES BELOW NORMAL WEDNESDAY THROUGH FRIDAY. A WEAK RIDGE OF HIGH PRESSURE WILL BUILD ACROSS THE AREA ON FRIDAY...WITH DRIER CONDITIONS EXPECTED. && .AVIATION...(FOR THE 12Z TAFS THROUGH LATE TONIGHT) ISSUED AT 345 AM MDT SAT MAR 29 2014 VFR CONDITIONS EXPECTED TODAY AND TONIGHT WITH MOSTLY CLEAR SKIES. WINDY CONDITIONS WILL RETURN TO SOUTHEAST WYOMING AFTER 15Z TODAY WITH GUSTS UP TO 45 KNOTS POSSIBLE ALONG AND WEST OF THE LARAMIE RANGE. IT WILL BE BREEZY ACROSS WESTERN NEBRASKA WITH GUSTS UP TO 30 KNOTS AT TIMES THIS AFTERNOON. && .FIRE WEATHER... ISSUED AT 414 AM MDT SAT MAR 29 2014 A WARM AND DRY AIRMASS WILL BE IN PLACE OVER THE REGION THROUGH THE WEEKEND. HIGHS WILL BE 10-15 DEGREES ABOVE NORMAL. MINIMUM HUMIDITY VALUES WILL FALL INTO THE 10-15 PERCENT RANGE OVER THE NEBRASKA PANHANDLE THIS AFTERNOON AND WILL COMBINE WITH GUSTY SOUTHWEST WINDS TO PRODUCE CRITICAL FIRE WEATHER CONDITIONS. A RED FLAG WARNING IS IN EFFECT THIS AFTERNOON FOR THE PANHANDLE SINCE FUELS ARE CONDUCIVE TO FIRE GROWTH IN THAT REGION. WHILE HUMIDITY VALUES WILL BE SIMILAR ON SUNDAY AFTERNOON...WIND SPEEDS SHOULD BE LESS SO ONLY AN ELEVATED FIRE WEATHER THREAT IS EXPECTED. COOLER TEMPERATURES WILL OCCUR ON MONDAY BEHIND A COLD FRONT THAT WILL PASS OVER THE REGION ON SUNDAY NIGHT. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...NONE. NE...RED FLAG WARNING UNTIL 7 PM MDT THIS EVENING FOR NEZ311>313. && $$ UPDATE...SML SHORT TERM...FINCH LONG TERM...TJT AVIATION...TJT FIRE WEATHER...FINCH
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
445 AM MDT SAT MAR 29 2014 .SHORT TERM...(TODAY AND TONIGHT) MAIN WEATHER STORIES THROUGH THIS EVENING WILL BE THE WARM TEMPERATURES AND ASSOCIATED FIRE WEATHER CONCERNS AND THE WINDY CONDITIONS ALONG AND WEST OF THE LARAMIE RANGE. HIGHS THIS AFTN ARE STILL EXPECTED TO CLIMB INTO THE 60S AND LOWER 70S ACROSS THE PLAINS. MAIN CHANGE TO THE FCST GRIDS FOR THIS AFTN WAS TO DECREASE DEWPOINTS...ESPECIALLY STRETCHING FROM LARAMIE COUNTY INTO THE SOUTHERN PANHANDLE. DEEP SOUTHWESTERLY FLOW IN THE LOW-TO-MIDLEVELS WILL COMBINE WITH EXCELLENT SOLAR INSULATION TO PRODUCE DEEP LLVL MIXING THIS AFTN AND IT IS THESE CONDITIONS THAT MOS OFTEN GROSSLY UNDERESTIMATES AFTN DEWPOINTS. WENT WITH A BLEND OF THE DRIER MAV AND RUC GUIDANCE AND THIS RESULTS IN MIN RH VALUES IN THE 10-15 PERCENT RANGE OVER THE PANHANDLE. EXCELLENT MIXING WILL TAP INTO 25-30 KTS AT THE TOP OF THE MIXED LAYER. THUS...DECIDED TO ISSUE A RFW FOR THE ENTIRE PANHANDLE. THE NEXT ITEM OF CONCERN IS WINDS TO THE WEST OF THE LARAMIE RANGE. THE GFS SHOWS 700MB WINDS OF 40-45 KTS FROM 18-00Z AND THE 700MB CAG-CPR GRADIENT IS AROUND 45 METERS. CONTEMPLATED PUTTING THE ARLINGTON AREA IN A HIGH WIND WARNING FOR THE AFTN...HOWEVER WOULD LIKE TO SEE THE LLVL GRADIENT AND WINDS ALOFT A BIT STRONGER. WILL LIKELY SEE GUSTS AROUND 45 KTS IN THE ARLINGTON AREA WITH THE FAVORABLE GAP WINDS. OUTSIDE OF ARLINGTON...COULD SEE GUSTS TO 40 KTS DURING PEAK MIXING. THE LLVL GRADIENT COMES DOWN BY THIS EVENING AND FLOW ALOFT BECOMES MORE SOUTHWESTERLY...SO WILL SEE WINDS DECREASE. ANOTHER WARM DAY ON SUNDAY AHEAD OF A SHORTWAVE. KEPT A SLIGHT CHANCE OF AFTN TSTMS IN THE FCST AS BOTH THE GFS AND NAM INDICATE LIFTED INDICES OF 0C TO -1C. MODELS CONTINUE TO INDICATE THAT THE UPPER LEVEL SYSTEM WILL MOVE DIRECTLY OVERHEAD ON SUNDAY NIGHT WITH A FROPA AFTER 06Z MON. BEST UPPER LEVEL DIVERGENCE AND LARGE SCALE LIFT IS LARGELY OFF TO THE NORTHEAST OF THE CWA...HOWEVER MAY HAVE TO WATCH THE NORTHEAST ZONES FOR ADVISORY AMOUNTS. THIS AREA WILL BE CLOSEST TO THE WESTERN EDGE OF A DEVELOPING TROWAL/FRONTOGENESIS FEATURE OVER SOUTH DAKOTA. JUST SOMETHING TO WATCH IN FUTURE MODEL RUNS. .LONG TERM...(EARLY TUESDAY MORNING THROUGH FRIDAY) ISSUED AT 445 AM MDT SAT MAR 29 2014 MAIN FORECAST CONCERN NEXT WEEK WILL BE A SLOW MOVING UPPER LEVEL LOW MOVING ACROSS THE GREAT BASIN REGION AND INTO THE ROCKY MOUNTAINS BY WEDNESDAY. ALTHOUGH MODELS ARE IN POOR AGREEMENT WITH THIS SYSTEM AND HAVE BEEN OVER THE LAST 48 HOURS...THERE IS STILL CONCERN OVER A POTENTIAL SIGNIFICANT STORM OVER PORTIONS OF THE HIGH PLAINS. FOR TUESDAY...ALL MODELS NOW SHOW THE COLD FRONT FROM SUNDAYS SYSTEM ALONG THE CONTINENTAL DIVIDE...RETREATING EASTWARD AS A WARM FRONT. WARM AIR ADVECTION ALOFT AND COOL UPSLOPE FLOW WILL COMBINE TO PRODUCE OVERRUNNING PRECIPITATION IN THE FORM OF SNOW ACROSS THE FORECAST AREA. INCREASED POP BETWEEN 30 TO 50 PERCENT ACROSS MOST OF THE FORECAST AREA WITH THE EXCEPTION OF EXTREME EASTERN ZONES ACROSS THE SOUTHERN NEBRASKA PANHANDLE. 1 TO 2 INCHES OF SNOW LOOKS POSSIBLE WITH THIS INITIAL OVERRUNNING EVENT TUESDAY...ESPECIALLY NORTH OF I80. AS THE WARM FRONT LIFTS NORTHEAST DURING THE DAY...THE SNOW WILL QUICKLY MELT AND/OR CHANGE TO RAIN AS TEMPERATURES INCREASE INTO THE 50S. ATTENTION THEN SHIFTS WESTWARD TUESDAY NIGHT AS THE MAIN UPPER LEVEL LOW MOVES ACROSS THE GREAT BASIN. MODELS ARE STRUGGLING WITH THE PLACEMENT...MOVEMENT...AND POTENTIAL EVOLUTION OF A STRONG WINTER STORM. ALL MODELS INDICATE A BRIEF BREAK EARLY WEDNESDAY BEFORE THE UPPER LEVEL LOW MOVES INTO THE ROCKY MOUNTAIN REGION AND ATTEMPTS TO BECOME BETTER ORGANIZED. THE ECMWF SHOWS A RATHER DISORGANIZED STORM SYSTEM...WITH THE MAIN LOW EJECTING NORTHEAST AND THEN DRIFTING EASTWARD INTO THE DAKOTAS...WHILE THE SOUTHERN ENERGY PUSHES INTO THE GREAT PLAINS AND THEN INITIATES STRONG CYCLOGENESIS IN KANSAS/MISSOURI LATE WEDNESDAY NIGHT. THE ECMWF INDICATES SPLIT FLOW ACROSS SOUTHEAST WYOMING WITH LIGHT SNOW ACCUMULATIONS NEAR I80 DUE TO THE SOUTHERN WAVE...AND LIGHT SNOW ACROSS CENTRAL WYOMING DUE TO THE MAIN LOW WITH LITTLE IN BETWEEN. THE GEM IS THE MOST AGGRESSIVE...SHOWING A COLORADO LOW SLOWLY EJECTING NORTHEAST FROM THE FOUR CORNERS REGION. THIS SCENARIO RESULTS IN WIDESPREAD MODERATE TO HEAVY SNOWFALL ACROSS THE FORECAST AREA BEGINNING WEDNESDAY EVENING AND LASTING THROUGH THURSDAY. THE 00Z GFS WAS CONSIDERABLY FURTHER SOUTH...WITH THE I80 CORRIDOR GETTING CLIPPED BY LIGHT SNOWFALL. HOWEVER...THE 06Z GFS IS FURTHER NORTH CLOSER TO THE GEM. MOST OF THE ENSEMBLE FORECASTS WERE IN BETWEEN THE GEM AND GFS LAST NIGHT...SO KEPT POP BETWEEN 25 TO 40 PERCENT OVER THE LOWER ELEVATIONS WITH POP NEAR 70 PERCENT IN THE MOUNTAINS THROUGH THURSDAY EVENING. WILL CONTINUE TO CLOSELY MONITOR THIS SYSTEM THROUGH THIS WEEKEND AND EARLY NEXT WEEK FOR CHANGES...BUT A SIGNIFICANT STORM SYSTEM APPEARS POSSIBLE NEXT WEEK. LOWERED TEMPERATURES BELOW NORMAL WEDNESDAY THROUGH FRIDAY. A WEAK RIDGE OF HIGH PRESSURE WILL BUILD ACROSS THE AREA ON FRIDAY...WITH DRIER CONDITIONS EXPECTED. && .AVIATION...(FOR THE 12Z TAFS THROUGH LATE TONIGHT) ISSUED AT 345 AM MDT SAT MAR 29 2014 VFR CONDITIONS EXPECTED TODAY AND TONIGHT WITH MOSTLY CLEAR SKIES. WINDY CONDITIONS WILL RETURN TO SOUTHEAST WYOMING AFTER 15Z TODAY WITH GUSTS UP TO 45 KNOTS POSSIBLE ALONG AND WEST OF THE LARAMIE RANGE. IT WILL BE BREEZY ACROSS WESTERN NEBRASKA WITH GUSTS UP TO 30 KNOTS AT TIMES THIS AFTERNOON. && .FIRE WEATHER... ISSUED AT 414 AM MDT SAT MAR 29 2014 A WARM AND DRY AIRMASS WILL BE IN PLACE OVER THE REGION THROUGH THE WEEKEND. HIGHS WILL BE 10-15 DEGREES ABOVE NORMAL. MINIMUM HUMIDITY VALUES WILL FALL INTO THE 10-15 PERCENT RANGE OVER THE NEBRASKA PANHANDLE THIS AFTERNOON AND WILL COMBINE WITH GUSTY SOUTHWEST WINDS TO PRODUCE CRITICAL FIRE WEATHER CONDITIONS. A RED FLAG WARNING IS IN EFFECT THIS AFTERNOON FOR THE PANHANDLE SINCE FUELS ARE CONDUCIVE TO FIRE GROWTH IN THAT REGION. WHILE HUMIDITY VALUES WILL BE SIMILAR ON SUNDAY AFTERNOON...WIND SPEEDS SHOULD BE LESS SO ONLY AN ELEVATED FIRE WEATHER THREAT IS EXPECTED. COOLER TEMPERATURES WILL OCCUR ON MONDAY BEHIND A COLD FRONT THAT WILL PASS OVER THE REGION ON SUNDAY NIGHT. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...NONE. NE...RED FLAG WARNING FROM 11 AM THIS MORNING TO 7 PM MDT THIS EVENING FOR NEZ311>313. && $$ SHORT TERM...FINCH LONG TERM...TJT AVIATION...TJT FIRE WEATHER...FINCH
AREA FORECAST DISCUSSION
NWS GRAY ME
319 AM EDT MON MAR 31 2014 .SYNOPSIS... LOW PRESSURE WILL MEANDER OFFSHORE TODAY...BEFORE FINALLY PULLING AWAY TONIGHT. HIGH PRESSURE WILL NUDGE IN BEHIND THE LOW FOR TUESDAY. A WEAK FRONT WILL CROSS THE AREA ON WEDNESDAY. HIGH PRESSURE WILL KEEP THINGS DRY THROUGH FRIDAY. LOW PRESSURE WILL TRACK INTO ONTARIO AND QUEBEC NEXT WEEKEND...SPREADING PRECIPITATION ACROSS MAINE AND NEW HAMPSHIRE. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... BANDS OF RAIN AND MIXED PRECIPITATION CONTINUE TO ROTATE BACK INTO THE FORECAST AREA FROM THE GULF OF MAINE EARLY THIS MORNING. THIS WILL ALLOW FOR UP TO A QUICK INCH OF ADDITIONAL RAINFALL ON TOP OF THE HEAVY RAINS THAT FELL OVER SOUTHERN LOCATIONS YESTERDAY. LATEST HRRR RUN DEPICTS THIS PRECIPITATION ASSOCIATED WITH THE UPPER LEVEL TROUGH VERY WELL. MUCH OF THE RAINFALL/MIX WILL BE DISSIPATING AROUND 16Z. AREAS OF SLEET AND FREEZING RAIN CONTINUE OVER CENTRAL LOCATIONS...HOWEVER IT HAS BEEN LIGHT. FOR NOW...WILL CONTINUE WITH THE WINTER WEATHER ADVISORIES THIS PACKAGE. WITH PLENTY OF CLOUD COVER AND STRONG...GUSTY NORTHERLY WINDS...WE DO NOT EXPECT THE TEMPERATURES TO RECOVER SIGNIFICANTLY TODAY. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/... STUBBORN SURFACE AND UPPER LEVEL LOW SLOWLY MOVE OUT TO SEA TONIGHT...ALLOWING FOR CLEARING TO FINALLY TAKE PLACE. SUNSHINE WILL MAKE AN APPEARANCE BACK TO OUR FORECAST AREA ON TUESDAY...WITH MODERATING TEMPERATURES AND MUCH LESS IN THE WAY OF GUSTY WINDS. && .LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/... MODELS ARE IN GENERAL AGREEMENT ON BROAD WESTERLY OR WEST- SOUTHWEST FLOW THIS PERIOD...THAT KEEPS ARCTIC AIR BOTTLED UP WELL TO OUR NORTH AND RESULTS IN NEAR NORMAL TEMPERATURES FOR THE PERIOD. DIFFERENCES EMERGE AFTER THURSDAY WITH TIMING OF INDIVIDUAL SHORTWAVES ADDING UNCERTAINTY TO THE FORECAST. IN THE DAILIES...A COLD FRONT WILL CROSS THE AREA WEDNESDAY FOLLOWED BY HIGH PRESSURE AND DRY AIR FOR THURSDAY AND FRIDAY. LOW PRESSURE APPROACHES FROM THE GREAT LAKES FOR SATURDAY AND SUNDAY. && .AVIATION /07Z MONDAY THROUGH FRIDAY/... SHORT TERM...ONE LAST ROUND OF LOCALLY IFR CONDITIONS AND RAIN/SNOW/SLEET WILL CONTINUE INTO THIS MORNING WITH IMPROVING CONDITIONS LATER IN THE DAY. WINDS WILL BE GUSTY OUT OF THE NORTH. LONG TERM... WED...SCT MVFR IN RAIN OR SNOW SHOWERS. SAT - SUN...AREAS OF MVFR IN RAIN AND SNOW WITH LCL IFR POSSIBLE. && .MARINE... SHORT TERM...NORTHERLY GALES EXPECTED RIGHT THROUGH TONIGHT AS LOW PRESSURE IS SLOW TO PULL AWAY. LONG TERM... THU...SMALL CRAFT WINDS AND SEAS ARE LIKELY. && .HYDROLOGY... A FLOOD WATCH REMAINS IN EFFECT AS MELT/RUNOFF SHOULD CONTINUE WITH ADDITIONAL BANDS OF HEAVY SHOWERS ROTATING ACROSS SOUTHERN PORTIONS OF THE AREA THIS MORNING. A RIVER FLOOD WARNING WILL CONTINUE FOR THE SUNCOOK RIVER. ICE IN THE GAGE CONTINUES TO EFFECT THE WEST CLAREMONT GAGE ON THE SUGAR RIVER. THANKS TO THE LOCAL PD FOR LOOKING INTO THIS ISSUE. && .TIDES/COASTAL FLOODING... TIDES AND WAVES WILL REMAIN MODESTLY HIGH TODAY. THERE COULD BE SOME BEACH EROSION...HOWEVER THE OVERALL TREND IS FOR THIS EVENT TO SETTLE DOWN WITH TIME TODAY AND TONIGHT. HENCE...NO ADVISORIES OR STATEMENTS WILL BE ISSUED. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...FLOOD WATCH UNTIL 2 PM EDT THIS AFTERNOON FOR MEZ012>014- 018>028. WINTER WEATHER ADVISORY UNTIL 8 AM EDT THIS MORNING FOR MEZ012>014-019>022. WINTER WEATHER ADVISORY UNTIL 2 PM EDT THIS AFTERNOON FOR MEZ007>009. NH...FLOOD WATCH UNTIL 2 PM EDT THIS AFTERNOON FOR NHZ003>010-013- 014. WINTER WEATHER ADVISORY UNTIL 8 AM EDT THIS MORNING FOR NHZ002>005-007. WINTER WEATHER ADVISORY UNTIL 2 PM EDT THIS AFTERNOON FOR NHZ001. MARINE...GALE WARNING UNTIL 5 AM EDT TUESDAY FOR ANZ150>154. && $$ SCHWIBS/CANNON
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
407 AM EDT MON MAR 31 2014 .SYNOPSIS... THE LARGE LOW PRESSURE SYSTEM FROM THE WEEKEND...IS NOW PULLING OUT TO SEA. LINGERING CLOUDS WILL BREAK UP TODAY AS HIGH PRESSURE STARTS TO BUILD...FOLLOWED BY SPRING LIKE CONDITIONS TUESDAY WITH TEMPERATURES WARMING INTO THE 50S TO NEAR 60. NEAR NORMAL TEMPERATURES ARE FIGURED FOR THE REMAINDER OF THE WORKWEEK. OUR NEXT GOOD CHANCE OF RAIN WILL BE FRIDAY INTO FRIDAY NIGHT AS A SYSTEM MOVES INTO THE GREAT LAKES REGION. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... 4 AM UPDATE... SNOW SHOWER ACTIVITY PERSISTS ACROSS THE FAR SERN FA. RETURNS HAVE DIMINISHED TO THE POINT THAT WE WERE ABLE TO LOWER ALL REMAINING FLAGS FOR THIS EVENT. MODEL SOUNDINGS SHOW ENOUGH DRY AIR FROM 850-700MB THAT I THINK WE WILL CLEAR OUT MORE QUICKLY THAN NORTHWEST FLOW NORMALLY ALLOWS IN EARLY SPRING. WILL FORECAST CLEARING SKIES FROM WEST TO EAST FROM MID MORNING INTO EARLY AFTERNOON. COOL AIRMASS ON BACKSIDE OF CYCLONE (925MB TEMPS -1C TO 2C) WILL LIMIT AFTERNOON MAXES TO THE MID 40S ACROSS NY, AND TO NEAR 50 OVER OUR SRN COUNTIES. 220 AM UPDATE... REMOVED A FEW MORE COUNTIES FROM THE ADVISORY AND WARNING AREA. WILL HOLD THE NEXT UPDATE PACKAGE FOR ANOTHER 1-2 HOURS. HOPEFULLY BY THEN WE CAN LOWER ALL FLAGS. 1210 AM UPDATE... REMOVED ONEIDA, MADISON AND BRADFORD COUNTIES FROM THE ADVISORY AREA. SNOW REMAINS PERSISTENT TO THE SOUTH AND EAST...HOWEVER THE EMBEDDED MODERATE TO HEAVY RETURNS ARE QUICKLY DIMINISHING. THE LATEST HRRR AND WRFARW REFLECTIVITY PROGS HAVE A DECENT HANDLE ON THE CURRENT SCENARIO. HOWEVER THE HRRR MIGHT BE A LITTLE TOO FAST AND AGGRESSIVE WITH TAPERING THE PRECIP OFF OVER THE NEXT HOUR. THE GOOD NEWS SO FAR IS THAT THERE IS LITTLE TO NO FREEZING DRIZZLE SHOWING UP ON THE BACK SIDE OF THE PRECIPITATION. A FEW "UP" WX TYPES HAVE SHOWN UP JUST AFTER THE PRECIP EXITED A STATION, BUT QUICKLY ENDED. SO I WILL HUG THE -FZDZ PTYPE TO THE 15-30 POP AREA BEHIND THE BANDS AND QUICKLY MOVE IT THROUGH. UPDATED AS OF 940 PM... UPGRADED BROOME...SUSQUEHANNA...WYOMING AND NORTHERN WAYNE CO/S TO WINTER STORM WARNING BASED ON SNOWFALL SPOTTER REPORTS. A FEW LOCATIONS IN THESE COUNTIES WILL EXCEED 10 INCHES. MANY REPORTS RECEIVED BETWEEN 5 AND 7 INCHES IN THE WARNING AREA SO WITH PRESENT RADAR TRENDS...BELIEVE MANY AREAS WILL SEE AT LEAST 7 INCHES IN THESE COUNTIES. FARTHER N LESS SNOW WAS REPORTED IN CHENANGO CO AND DELWARE/OTSEGO COUNTIES...TO THE TUNE OF 2-5 INCHES. I CAN SEE A COUPLE MORE INCHES IN THESE PLACES SO WILL STICK WITH ADVY THERE. FARTHER S OF THE WARNING AREA...SNOW IS BECOMING MORE WIDESPREAD BUT NOT CONCENTRATING INTO BANDS. AS THE UPPER LEVEL LOW PULLS AWAY...THE DEFORMATION BAND WILL TAPER DOWN AND WEAKEN...WITH MOST OF THE SNOW TO THE EAST TWD THE POCONOS AND WESTERN CATSKILLS. I THINK WE WILL SEE SNOW AMNTS OF 2-5 INCHES IN THE POCONOS/WESTERN CATSKILLS WITH 1-3 INCHES IN THE VALLEYS. SO WILL CONT ADVY/S IN THE REST OF NE PA AND SULLIVAN CO. PREVIOUS DSCN IS BELOW... WATER VAPOR IMAGERY SHOWS A CLOSED MID TO UPPER LEVEL LOW SPINNING OFF THE NJ COAST. A DEFORMATION ZONE OF LOCALLY HEAVY SNOW HAS SET UP TO THE WEST OF THIS UPPER LEVEL LOW FROM ABT UCA TO NORWICH TO THE CITY OF BINGHAMTON TO AVP. THERE WAS A SECONDARY BAND OF HEAVIER MIXED PRECIP...FROM DELAWARE CO INTO THE POCONOS. WITH MORE SHOWERLY LOOKING PRECIP TO THE S AND E. THIS AREA WAS MAINLY FREEZING RAIN...SLEET AND JUST PLAIN RAIN. THE RAP SHOWS THAT THIS UPPER LEVEL LOW WILL DRIFT EASTWARD BETWEEN 01Z AND 04Z AND THE DEFORMATION ZONE THAT WAS PRESENTLY AT THE WEST EDGE OF THE PRECIP SHIELD WILL WEAKEN. I BELIEVE ANOTHER BAND WILL FORM FARTHER TO THE S AND E AND AFFECT THE WESTERN CATSKILLS INTO PIKE CO/SRN WAYNE BTWN 1 AND 4Z. HOWEVER...THE CYCLONE WAS BECOMING MORE VERTICALLY STACKED AT THIS TIME AND THUS BELIEVE THE HEAVIEST SNOW FROM THIS STORM IN OUR AREA WILL BE OVER. SO HAVE ADJUSTED SNOW AMNTS DOWN A TOUCH FOR SULLIVAN AND PIKE CO/S. FARTHER N AND W...HAVE HAD TO CHASE SNOW AMNTS AS BANDING WAS LEADING TO RAPID SNOW ACCUMULATIONS. BUT AT THE SAME TIME SOME OF THE HIGHER RADAR RETURNS WERE RELATED TO THE MELTING LEVEL AND JUST SLEET AND WET SNOW WAS FALLING WITH LESS ACCUMULATION. SO WE HAVE RELIED HEAVILY ON SPOTTER REPORTS. THANKS TO ALL SPOTTERS WHO HAVE SENT REPORTS IN...THEY HAVE BEEN MOST HELPFUL. WILL CONT WINTER WX ADVY WHERE IT IS IN EFFECT FOR NOW. LIKELY WILL DROP CORTLAND AND TIOGA CO/S BY 9 PM OR SO AS IT LOOKS LIKE THE DEFORMATION BAND HAS HALTED ITS WESTWARD PROGRESS. I WILL WAIT AND SEE ON THIS. REST OF FORECAST AREA TO THE WEST OF THE PRECIP SHIELD WILL BE JUST CLOUDY AND BLUSTERY FOR THE NIGHTTIME HOURS. && .SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/... HIGH PRESSURE WILL CONTROL OUR WEATHER FOR MOST OF THIS PERIOD. A STRENGTHENING CYCLONE WILL MOVE INTO THE WESTERN GREAT LAKES TONIGHT AND PULL WARM AIR NORTHWARD INTO THE OHIO VALLEY AND NY/PA. AS A RESULT, TEMPERATURES WILL CLIMB INTO THE MID 50S TO LOWER 60S ON TUESDAY, LIKELY RESULTING IN THE WARMEST AIR WE HAVE EXPERIENCED SINCE LATE AUTUMN. A SHORT WAVE WITH LIMITED MOISTURE MAY BRING A FEW SHOWERS TO THE REGION TUESDAY NIGHT AND EARLY WEDNESDAY. MOST OF THE AREA WILL REMAIN PARTLY SUNNY AND RAIN FREE. TEMPERATURES WILL PUSH INTO LOWER OR MIDDLE 50S ON WEDNESDAY AFTERNOON. && .LONG TERM /THURSDAY THROUGH SUNDAY/... 345 AM UPDATE... FORECAST UPDATED FOR LATEST WPC GUIDANCE AND MODEL TRENDS. LATEST GFS/ECMWF RUNS INCREASE CONFIDENCE IN THE CLOSED UPPER LOW MOVING IN FROM THE UPPER MIDWEST FRIDAY INTO THE GREAT LAKES REGION FRIDAY NIGHT-SATURDAY...WITH SHIELD OF MOISTURE EXTENDING WELL EAST INTO OUR REGION. WHILE I DID NOT GO QUITE AS HIGH AS WPC JUST YET...I DID INCREASE POPS INTO LIKELY CATEGORY DURING THE FRI-FRI NIGHT PERIOD. PREVIOUS DISCUSSION... SLIGHTLY COOLER WEATHER BUILDS INTO THE AREA WEDNESDAY NIGHT INTO THURSDAY WHICH WILL RETURN TEMPS CLOSER TO SEASONAL NORMS. THE MAIN FEATURE OF INTEREST IN THE EXTENDED WILL BE THE DEVELOPMENT OF A CLOSED UPPER LOW OVER THE UPPER MIDWEST BY FRIDAY. SOME PRECIPITATION, MAINLY RAIN SHOWERS, MAY TRY TO SNEAK INTO THE SOUTHERN PART OF THE CWA LATE THURSDAY ALONG A BOUNDARY. FOR THE MOST PART THOUGH WE STAY PRECIPITATION FREE UNTIL FRIDAY NIGHT WHEN A FRONT ASSOCIATED WITH THE CLOSED LOW MENTIONED ABOVE, MOVES THROUGH. WE ARE TALKING ALMOST AN ENTIRELY RAIN EVENT BUT SOME ENOUGH COLD AIR MAY REMAIN FOR SOME WET SNOW OVER NORTHERN ONEIDA COUNTY FRIDAY NIGHT. PRECIPITATION ENDS SATURDAY AS OUR REGION GETS INTO A DRY SLOT. BEYOND SATURDAY WE COOL BACK TO BELOW NORMAL FOR THE 2ND HALF OF THE WEEKEND INTO EARLY NEXT WEEK AS THE ACTUAL UPPER LOW MOVES JUST TO OUR NORTH. && .AVIATION /08Z MONDAY THROUGH FRIDAY/... 06Z UPDATE... IMPROVING CONDITIONS AS SYSTEM ALONG THE COAST CONTINUES TO PULL AWAY. SHARP OUTER RIM OF SNOW WILL STILL CAUSE INTERMITTENT IFR SNOW AT KAVP 06Z-08Z...OTHERWISE ONLY DEALING WITH MVFR CIGS ACROSS ALL TERMINALS EARLY THIS MORNING. AIR MASS IS NOT COLD ENOUGH TO GENERATE ADDITIONAL CLOUDS OFF OF LAKE ONTARIO...AND WIND DIRECTION HAS A LOT OF NORTHERLY COMPONENT...THUS EXPECTING SCATTERING OUT OF CIGS TO OCCUR THIS MORNING 12Z-16Z INSTEAD OF THE USUAL LONGER PERSISTING CIGS THAT OFTEN OCCUR BEHIND A SYSTEM. BEHIND THE EXITING RIM OF SNOW...MODELS/SOUNDINGS ARE ACTUALLY TOO MOIST COMPARED TO OBSERVED CIGS...AND THUS I AM NOT EXPECTING IFR CIG AT KBGM AT THIS POINT AS GUIDANCE WOULD SUGGEST. NNW WINDS 10-14 KT WITH GUSTS TO AROUND 20 KTS MUCH OF TODAY...THEN DECOUPLING TO WELL UNDER 10 KTS FROM NE OR VARIABLE THIS EVENING. OUTLOOK... LATE MON NGT THROUGH TUE NGT...VFR. WED/THU/FRI...RESTRICTIONS POSSIBLE IN LIGHT RAIN SOUTHERN TERMINALS WED-THU...ALL TERMINALS THU NGT-FRI. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...NONE. NY...NONE. && $$ SYNOPSIS...DJP/MDP NEAR TERM...DJP SHORT TERM...DJP LONG TERM...HEDEN/MDP AVIATION...MDP
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
400 AM EDT MON MAR 31 2014 .SYNOPSIS... THE LARGE LOW PRESSURE SYSTEM FROM THE WEEKEND...IS NOW PULLING OUT TO SEA. LINGERING CLOUDS WILL BREAK UP TODAY AS HIGH PRESSURE STARTS TO BUILD...FOLLOWED BY SPRING LIKE CONDITIONS TUESDAY WITH TEMPERATURES WARMING INTO THE 50S TO NEAR 60. NEAR NORMAL TEMPERATURES ARE FIGURED FOR THE REMAINDER OF THE WORKWEEK. OUR NEXT GOOD CHANCE OF RAIN WILL BE FRIDAY INTO FRIDAY NIGHT AS A SYSTEM MOVES INTO THE GREAT LAKES REGION. && .NEAR TERM /UNTIL 8 AM THIS MORNING/... 4 AM UPDATE... SNOW SHOWER ACTIVITY PERSISTS ACROSS THE FAR SERN FA. RETURNS HAVE DIMINISHED TO THE POINT THAT WE WERE ABLE TO LOWER ALL REMAINING FLAGS FOR THIS EVENT. MODEL SOUNDINGS SHOW ENOUGH DRY AIR FROM 850-700MB THAT I THINK WE WILL CLEAR OUT MORE QUICKLY THAN NORTHWEST FLOW NORMALLY ALLOWS. WILL FORECAST CLEARING SKIES FROM WEST TO EAST FROM MID MORNING INTO EARLY AFTERNOON. COOL AIRMASS ON BACKSIDE OF CYCLONE (925MB TEMPS -1C TO 2C) WILL LIMIT AFTERNOON MAXES TO THE MID 40S ACROSS NY, AND NEAR 50 OUR SRN COUNTIES. 220 AM UPDATE... REMOVED A FEW MORE COUNTIES FROM THE ADVISORY AND WARNING AREA. WILL HOLD THE NEXT UPDATE PACKAGE FOR ANOTHER 1-2 HOURS. HOPEFULLY BY THEN WE CAN LOWER ALL FLAGS. 1210 AM UPDATE... REMOVED ONEIDA, MADISON AND BRADFORD COUNTIES FROM THE ADVISORY AREA. SNOW REMAINS PERSISTENT TO THE SOUTH AND EAST...HOWEVER THE EMBEDDED MODERATE TO HEAVY RETURNS ARE QUICKLY DIMINISHING. THE LATEST HRRR AND WRFARW REFLECTIVITY PROGS HAVE A DECENT HANDLE ON THE CURRENT SCENARIO. HOWEVER THE HRRR MIGHT BE A LITTLE TOO FAST AND AGGRESSIVE WITH TAPERING THE PRECIP OFF OVER THE NEXT HOUR. THE GOOD NEWS SO FAR IS THAT THERE IS LITTLE TO NO FREEZING DRIZZLE SHOWING UP ON THE BACK SIDE OF THE PRECIPITATION. A FEW "UP" WX TYPES HAVE SHOWN UP JUST AFTER THE PRECIP EXITED A STATION, BUT QUICKLY ENDED. SO I WILL HUG THE -FZDZ PTYPE TO THE 15-30 POP AREA BEHIND THE BANDS AND QUICKLY MOVE IT THROUGH. UPDATED AS OF 940 PM... UPGRADED BROOME...SUSQUEHANNA...WYOMING AND NORTHERN WAYNE CO/S TO WINTER STORM WARNING BASED ON SNOWFALL SPOTTER REPORTS. A FEW LOCATIONS IN THESE COUNTIES WILL EXCEED 10 INCHES. MANY REPORTS RECEIVED BETWEEN 5 AND 7 INCHES IN THE WARNING AREA SO WITH PRESENT RADAR TRENDS...BELIEVE MANY AREAS WILL SEE AT LEAST 7 INCHES IN THESE COUNTIES. FARTHER N LESS SNOW WAS REPORTED IN CHENANGO CO AND DELWARE/OTSEGO COUNTIES...TO THE TUNE OF 2-5 INCHES. I CAN SEE A COUPLE MORE INCHES IN THESE PLACES SO WILL STICK WITH ADVY THERE. FARTHER S OF THE WARNING AREA...SNOW IS BECOMING MORE WIDESPREAD BUT NOT CONCENTRATING INTO BANDS. AS THE UPPER LEVEL LOW PULLS AWAY...THE DEFORMATION BAND WILL TAPER DOWN AND WEAKEN...WITH MOST OF THE SNOW TO THE EAST TWD THE POCONOS AND WESTERN CATSKILLS. I THINK WE WILL SEE SNOW AMNTS OF 2-5 INCHES IN THE POCONOS/WESTERN CATSKILLS WITH 1-3 INCHES IN THE VALLEYS. SO WILL CONT ADVY/S IN THE REST OF NE PA AND SULLIVAN CO. PREVIOUS DSCN IS BELOW... WATER VAPOR IMAGERY SHOWS A CLOSED MID TO UPPER LEVEL LOW SPINNING OFF THE NJ COAST. A DEFORMATION ZONE OF LOCALLY HEAVY SNOW HAS SET UP TO THE WEST OF THIS UPPER LEVEL LOW FROM ABT UCA TO NORWICH TO THE CITY OF BINGHAMTON TO AVP. THERE WAS A SECONDARY BAND OF HEAVIER MIXED PRECIP...FROM DELAWARE CO INTO THE POCONOS. WITH MORE SHOWERLY LOOKING PRECIP TO THE S AND E. THIS AREA WAS MAINLY FREEZING RAIN...SLEET AND JUST PLAIN RAIN. THE RAP SHOWS THAT THIS UPPER LEVEL LOW WILL DRIFT EASTWARD BETWEEN 01Z AND 04Z AND THE DEFORMATION ZONE THAT WAS PRESENTLY AT THE WEST EDGE OF THE PRECIP SHIELD WILL WEAKEN. I BELIEVE ANOTHER BAND WILL FORM FARTHER TO THE S AND E AND AFFECT THE WESTERN CATSKILLS INTO PIKE CO/SRN WAYNE BTWN 1 AND 4Z. HOWEVER...THE CYCLONE WAS BECOMING MORE VERTICALLY STACKED AT THIS TIME AND THUS BELIEVE THE HEAVIEST SNOW FROM THIS STORM IN OUR AREA WILL BE OVER. SO HAVE ADJUSTED SNOW AMNTS DOWN A TOUCH FOR SULLIVAN AND PIKE CO/S. FARTHER N AND W...HAVE HAD TO CHASE SNOW AMNTS AS BANDING WAS LEADING TO RAPID SNOW ACCUMULATIONS. BUT AT THE SAME TIME SOME OF THE HIGHER RADAR RETURNS WERE RELATED TO THE MELTING LEVEL AND JUST SLEET AND WET SNOW WAS FALLING WITH LESS ACCUMULATION. SO WE HAVE RELIED HEAVILY ON SPOTTER REPORTS. THANKS TO ALL SPOTTERS WHO HAVE SENT REPORTS IN...THEY HAVE BEEN MOST HELPFUL. WILL CONT WINTER WX ADVY WHERE IT IS IN EFFECT FOR NOW. LIKELY WILL DROP CORTLAND AND TIOGA CO/S BY 9 PM OR SO AS IT LOOKS LIKE THE DEFORMATION BAND HAS HALTED ITS WESTWARD PROGRESS. I WILL WAIT AND SEE ON THIS. REST OF FORECAST AREA TO THE WEST OF THE PRECIP SHIELD WILL BE JUST CLOUDY AND BLUSTERY FOR THE NIGHTTIME HOURS. && .SHORT TERM /8 AM THIS MORNING THROUGH WEDNESDAY NIGHT/... 320 PM UPDATE... HIPRES WL BUILD IN ON MONDAY AS COASTAL STORM RIDES OFF TO THE NORTHEAST TAKING MOISTURE WITH IT. ONLY LINGERING AFFECT WL BE CLOUD CVR VRY EARLY IN THE MRNG BFR DRY AIR MVS IN FM THE NW. SKIES WL BE MOSUNNY AND TEMPS WL HANDILY RISE INTO THE 40S/NR 50 UNDER STRONG MARCH SUN TOMORROW. 500MB HEIGHTS FOR TUESDAY WILL CLIMB TO NR 567DM WITH S/WV RIDGE BUILDING DIRECTLY OVRHD. GIVEN STRONG MARCH SUN HV GONE ABV GUIDANCE NUMBERS WITH HIGHS IN THE U50S/LWR 60S IN THE VLYS. NO WX IS EXPECTED UNTIL NEXT S/WV APPCHS TUE NGT, SPREADING SHOWERS INTO PORTIONS OF THE AREA MAINLY ACRS NRN ZONES. && .LONG TERM /THURSDAY THROUGH SUNDAY/... 345 AM UPDATE... FORECAST UPDATED FOR LATEST WPC GUIDANCE AND MODEL TRENDS. LATEST GFS/ECMWF RUNS INCREASE CONFIDENCE IN THE CLOSED UPPER LOW MOVING IN FROM THE UPPER MIDWEST FRIDAY INTO THE GREAT LAKES REGION FRIDAY NIGHT-SATURDAY...WITH SHIELD OF MOISTURE EXTENDING WELL EAST INTO OUR REGION. WHILE I DID NOT GO QUITE AS HIGH AS WPC JUST YET...I DID INCREASE POPS INTO LIKELY CATEGORY DURING THE FRI-FRI NIGHT PERIOD. PREVIOUS DISCUSSION... SLIGHTLY COOLER WEATHER BUILDS INTO THE AREA WEDNESDAY NIGHT INTO THURSDAY WHICH WILL RETURN TEMPS CLOSER TO SEASONAL NORMS. THE MAIN FEATURE OF INTEREST IN THE EXTENDED WILL BE THE DEVELOPMENT OF A CLOSED UPPER LOW OVER THE UPPER MIDWEST BY FRIDAY. SOME PRECIPITATION, MAINLY RAIN SHOWERS, MAY TRY TO SNEAK INTO THE SOUTHERN PART OF THE CWA LATE THURSDAY ALONG A BOUNDARY. FOR THE MOST PART THOUGH WE STAY PRECIPITATION FREE UNTIL FRIDAY NIGHT WHEN A FRONT ASSOCIATED WITH THE CLOSED LOW MENTIONED ABOVE, MOVES THROUGH. WE ARE TALKING ALMOST AN ENTIRELY RAIN EVENT BUT SOME ENOUGH COLD AIR MAY REMAIN FOR SOME WET SNOW OVER NORTHERN ONEIDA COUNTY FRIDAY NIGHT. PRECIPITATION ENDS SATURDAY AS OUR REGION GETS INTO A DRY SLOT. BEYOND SATURDAY WE COOL BACK TO BELOW NORMAL FOR THE 2ND HALF OF THE WEEKEND INTO EARLY NEXT WEEK AS THE ACTUAL UPPER LOW MOVES JUST TO OUR NORTH. && .AVIATION /08Z MONDAY THROUGH FRIDAY/... 06Z UPDATE... IMPROVING CONDITIONS AS SYSTEM ALONG THE COAST CONTINUES TO PULL AWAY. SHARP OUTER RIM OF SNOW WILL STILL CAUSE INTERMITTENT IFR SNOW AT KAVP 06Z-08Z...OTHERWISE ONLY DEALING WITH MVFR CIGS ACROSS ALL TERMINALS EARLY THIS MORNING. AIR MASS IS NOT COLD ENOUGH TO GENERATE ADDITIONAL CLOUDS OFF OF LAKE ONTARIO...AND WIND DIRECTION HAS A LOT OF NORTHERLY COMPONENT...THUS EXPECTING SCATTERING OUT OF CIGS TO OCCUR THIS MORNING 12Z-16Z INSTEAD OF THE USUAL LONGER PERSISTING CIGS THAT OFTEN OCCUR BEHIND A SYSTEM. BEHIND THE EXITING RIM OF SNOW...MODELS/SOUNDINGS ARE ACTUALLY TOO MOIST COMPARED TO OBSERVED CIGS...AND THUS I AM NOT EXPECTING IFR CIG AT KBGM AT THIS POINT AS GUIDANCE WOULD SUGGEST. NNW WINDS 10-14 KT WITH GUSTS TO AROUND 20 KTS MUCH OF TODAY...THEN DECOUPLING TO WELL UNDER 10 KTS FROM NE OR VARIABLE THIS EVENING. OUTLOOK... LATE MON NGT THROUGH TUE NGT...VFR. WED/THU/FRI...RESTRICTIONS POSSIBLE IN LIGHT RAIN SOUTHERN TERMINALS WED-THU...ALL TERMINALS THU NGT-FRI. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...NONE. NY...NONE. && $$ SYNOPSIS...DJP/MDP NEAR TERM...DJP SHORT TERM...DJP LONG TERM...HEDEN/MDP AVIATION...MDP
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
351 AM EDT MON MAR 31 2014 .SYNOPSIS... THE LARGE LOW PRESSURE SYSTEM FROM THE WEEKEND...IS NOW PULLING AWAY OUT TO SEA. LINGERING CLOUDS WILL BREAK UP TODAY AS HIGH PRESSURE STARTS TO BUILD...FOLLOWED BY SPRINGLIKE CONDITIONS TUESDAY WITH TEMPERATURES WARMING INTO THE 50S TO NEAR 60. NEAR NORMAL TEMPERATURES ARE FIGURED FOR THE REMAINDER OF THE WORKWEEK. OUR NEXT GOOD CHANCE OF RAIN WILL BE FRIDAY INTO FRIDAY NIGHT AS A SYSTEM MOVES INTO THE GREAT LAKES REGION. && .NEAR TERM /UNTIL 8 AM THIS MORNING/... 220 AM UPDATE... REMOVED A FEW MORE COUNTIES FROM THE ADVISORY AND WARNING AREA. WILL HOLD THE NEXT UPDATE PACKAGE FOR ANOTHER 1-2 HOURS. HOPEFULLY BY THEN WE CAN LOWER ALL FLAGS. 1210 AM UPDATE... REMOVED ONEIDA, MADISON AND BRADFORD COUNTIES FROM THE ADVISORY AREA. SNOW REMAINS PERSISTENT TO THE SOUTH AND EAST...HOWEVER THE EMBEDDED MODERATE TO HEAVY RETURNS ARE QUICKLY DIMINISHING. THE LATEST HRRR AND WRFARW REFLECTIVITY PROGS HAVE A DECENT HANDLE ON THE CURRENT SCENARIO. HOWEVER THE HRRR MIGHT BE A LITTLE TOO FAST AND AGGRESSIVE WITH TAPERING THE PRECIP OFF OVER THE NEXT HOUR. THE GOOD NEWS SO FAR IS THAT THERE IS LITTLE TO NO FREEZING DRIZZLE SHOWING UP ON THE BACK SIDE OF THE PRECIPITATION. A FEW "UP" WX TYPES HAVE SHOWN UP JUST AFTER THE PRECIP EXITED A STATION, BUT QUICKLY ENDED. SO I WILL HUG THE -FZDZ PTYPE TO THE 15-30 POP AREA BEHIND THE BANDS AND QUICKLY MOVE IT THROUGH. UPDATED AS OF 940 PM... UPGRADED BROOME...SUSQUEHANNA...WYOMING AND NORTHERN WAYNE CO/S TO WINTER STORM WARNING BASED ON SNOWFALL SPOTTER REPORTS. A FEW LOCATIONS IN THESE COUNTIES WILL EXCEED 10 INCHES. MANY REPORTS RECEIVED BETWEEN 5 AND 7 INCHES IN THE WARNING AREA SO WITH PRESENT RADAR TRENDS...BELIEVE MANY AREAS WILL SEE AT LEAST 7 INCHES IN THESE COUNTIES. FARTHER N LESS SNOW WAS REPORTED IN CHENANGO CO AND DELWARE/OTSEGO COUNTIES...TO THE TUNE OF 2-5 INCHES. I CAN SEE A COUPLE MORE INCHES IN THESE PLACES SO WILL STICK WITH ADVY THERE. FARTHER S OF THE WARNING AREA...SNOW IS BECOMING MORE WIDESPREAD BUT NOT CONCENTRATING INTO BANDS. AS THE UPPER LEVEL LOW PULLS AWAY...THE DEFORMATION BAND WILL TAPER DOWN AND WEAKEN...WITH MOST OF THE SNOW TO THE EAST TWD THE POCONOS AND WESTERN CATSKILLS. I THINK WE WILL SEE SNOW AMNTS OF 2-5 INCHES IN THE POCONOS/WESTERN CATSKILLS WITH 1-3 INCHES IN THE VALLEYS. SO WILL CONT ADVY/S IN THE REST OF NE PA AND SULLIVAN CO. PREVIOUS DSCN IS BELOW... WATER VAPOR IMAGERY SHOWS A CLOSED MID TO UPPER LEVEL LOW SPINNING OFF THE NJ COAST. A DEFORMATION ZONE OF LOCALLY HEAVY SNOW HAS SET UP TO THE WEST OF THIS UPPER LEVEL LOW FROM ABT UCA TO NORWICH TO THE CITY OF BINGHAMTON TO AVP. THERE WAS A SECONDARY BAND OF HEAVIER MIXED PRECIP...FROM DELAWARE CO INTO THE POCONOS. WITH MORE SHOWERLY LOOKING PRECIP TO THE S AND E. THIS AREA WAS MAINLY FREEZING RAIN...SLEET AND JUST PLAIN RAIN. THE RAP SHOWS THAT THIS UPPER LEVEL LOW WILL DRIFT EASTWARD BETWEEN 01Z AND 04Z AND THE DEFORMATION ZONE THAT WAS PRESENTLY AT THE WEST EDGE OF THE PRECIP SHIELD WILL WEAKEN. I BELIEVE ANOTHER BAND WILL FORM FARTHER TO THE S AND E AND AFFECT THE WESTERN CATSKILLS INTO PIKE CO/SRN WAYNE BTWN 1 AND 4Z. HOWEVER...THE CYCLONE WAS BECOMING MORE VERTICALLY STACKED AT THIS TIME AND THUS BELIEVE THE HEAVIEST SNOW FROM THIS STORM IN OUR AREA WILL BE OVER. SO HAVE ADJUSTED SNOW AMNTS DOWN A TOUCH FOR SULLIVAN AND PIKE CO/S. FARTHER N AND W...HAVE HAD TO CHASE SNOW AMNTS AS BANDING WAS LEADING TO RAPID SNOW ACCUMULATIONS. BUT AT THE SAME TIME SOME OF THE HIGHER RADAR RETURNS WERE RELATED TO THE MELTING LEVEL AND JUST SLEET AND WET SNOW WAS FALLING WITH LESS ACCUMULATION. SO WE HAVE RELIED HEAVILY ON SPOTTER REPORTS. THANKS TO ALL SPOTTERS WHO HAVE SENT REPORTS IN...THEY HAVE BEEN MOST HELPFUL. WILL CONT WINTER WX ADVY WHERE IT IS IN EFFECT FOR NOW. LIKELY WILL DROP CORTLAND AND TIOGA CO/S BY 9 PM OR SO AS IT LOOKS LIKE THE DEFORMATION BAND HAS HALTED ITS WESTWARD PROGRESS. I WILL WAIT AND SEE ON THIS. REST OF FORECAST AREA TO THE WEST OF THE PRECIP SHIELD WILL BE JUST CLOUDY AND BLUSTERY FOR THE NIGHTTIME HOURS. && .SHORT TERM /8 AM THIS MORNING THROUGH WEDNESDAY NIGHT/... 320 PM UPDATE... HIPRES WL BUILD IN ON MONDAY AS COASTAL STORM RIDES OFF TO THE NORTHEAST TAKING MOISTURE WITH IT. ONLY LINGERING AFFECT WL BE CLOUD CVR VRY EARLY IN THE MRNG BFR DRY AIR MVS IN FM THE NW. SKIES WL BE MOSUNNY AND TEMPS WL HANDILY RISE INTO THE 40S/NR 50 UNDER STRONG MARCH SUN TOMORROW. 500MB HEIGHTS FOR TUESDAY WILL CLIMB TO NR 567DM WITH S/WV RIDGE BUILDING DIRECTLY OVRHD. GIVEN STRONG MARCH SUN HV GONE ABV GUIDANCE NUMBERS WITH HIGHS IN THE U50S/LWR 60S IN THE VLYS. NO WX IS EXPECTED UNTIL NEXT S/WV APPCHS TUE NGT, SPREADING SHOWERS INTO PORTIONS OF THE AREA MAINLY ACRS NRN ZONES. && .LONG TERM /THURSDAY THROUGH SUNDAY/... 345 AM UPDATE... FORECAST UPDATED FOR LATEST WPC GUIDANCE AND MODEL TRENDS. LATEST GFS/ECMWF RUNS INCREASE CONFIDENCE IN THE CLOSED UPPER LOW MOVING IN FROM THE UPPER MIDWEST FRIDAY INTO THE GREAT LAKES REGION FRIDAY NIGHT-SATURDAY...WITH SHIELD OF MOISTURE EXTENDING WELL EAST INTO OUR REGION. WHILE I DID NOT GO QUITE AS HIGH AS WPC JUST YET...I DID INCREASE POPS INTO LIKELY CATEGORY DURING THE FRI-FRI NIGHT PERIOD. PREVIOUS DISCUSSION... SLIGHTLY COOLER WEATHER BUILDS INTO THE AREA WEDNESDAY NIGHT INTO THURSDAY WHICH WILL RETURN TEMPS CLOSER TO SEASONAL NORMS. THE MAIN FEATURE OF INTEREST IN THE EXTENDED WILL BE THE DEVELOPMENT OF A CLOSED UPPER LOW OVER THE UPPER MIDWEST BY FRIDAY. SOME PRECIPITATION, MAINLY RAIN SHOWERS, MAY TRY TO SNEAK INTO THE SOUTHERN PART OF THE CWA LATE THURSDAY ALONG A BOUNDARY. FOR THE MOST PART THOUGH WE STAY PRECIPITATION FREE UNTIL FRIDAY NIGHT WHEN A FRONT ASSOCIATED WITH THE CLOSED LOW MENTIONED ABOVE, MOVES THROUGH. WE ARE TALKING ALMOST AN ENTIRELY RAIN EVENT BUT SOME ENOUGH COLD AIR MAY REMAIN FOR SOME WET SNOW OVER NORTHERN ONEIDA COUNTY FRIDAY NIGHT. PRECIPITATION ENDS SATURDAY AS OUR REGION GETS INTO A DRY SLOT. BEYOND SATURDAY WE COOL BACK TO BELOW NORMAL FOR THE 2ND HALF OF THE WEEKEND INTO EARLY NEXT WEEK AS THE ACTUAL UPPER LOW MOVES JUST TO OUR NORTH. && .AVIATION /08Z MONDAY THROUGH FRIDAY/... 06Z UPDATE... IMPROVING CONDITIONS AS SYSTEM ALONG THE COAST CONTINUES TO PULL AWAY. SHARP OUTER RIM OF SNOW WILL STILL CAUSE INTERMITTENT IFR SNOW AT KAVP 06Z-08Z...OTHERWISE ONLY DEALING WITH MVFR CIGS ACROSS ALL TERMINALS EARLY THIS MORNING. AIR MASS IS NOT COLD ENOUGH TO GENERATE ADDITIONAL CLOUDS OFF OF LAKE ONTARIO...AND WIND DIRECTION HAS A LOT OF NORTHERLY COMPONENT...THUS EXPECTING SCATTERING OUT OF CIGS TO OCCUR THIS MORNING 12Z-16Z INSTEAD OF THE USUAL LONGER PERSISTING CIGS THAT OFTEN OCCUR BEHIND A SYSTEM. BEHIND THE EXITING RIM OF SNOW...MODELS/SOUNDINGS ARE ACTUALLY TOO MOIST COMPARED TO OBSERVED CIGS...AND THUS I AM NOT EXPECTING IFR CIG AT KBGM AT THIS POINT AS GUIDANCE WOULD SUGGEST. NNW WINDS 10-14 KT WITH GUSTS TO AROUND 20 KTS MUCH OF TODAY...THEN DECOUPLING TO WELL UNDER 10 KTS FROM NE OR VARIABLE THIS EVENING. OUTLOOK... LATE MON NGT THROUGH TUE NGT...VFR. WED/THU/FRI...RESTRICTIONS POSSIBLE IN LIGHT RAIN SOUTHERN TERMINALS WED-THU...ALL TERMINALS THU NGT-FRI. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...WINTER WEATHER ADVISORY UNTIL 8 AM EDT THIS MORNING FOR PAZ044- 047-048-072. WINTER STORM WARNING UNTIL 8 AM EDT THIS MORNING FOR PAZ039- 040-043. NY...WINTER WEATHER ADVISORY UNTIL 8 AM EDT THIS MORNING FOR NYZ062. && $$ SYNOPSIS...DJP/MDP NEAR TERM...DJN/DJP SHORT TERM...PVN LONG TERM...HEDEN/MDP AVIATION...MDP
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
221 AM EDT MON MAR 31 2014 .SYNOPSIS... A LATE SEASON WINTER STORM THAT WAS CENTERED OFF THE NEW JERSEY COAST WILL SHIFT FARTHER OUT TO SEA OVERNIGHT. ALL THE SNOW AND MIXED PRECIPITATION WILL TAPER OFF LATE TONIGHT. IN THE MEANTIME...TRAVEL WILL BE HAZARDOUS TONIGHT ACROSS MUCH OF NORTHEAST PENNSYLVANIA AND IN CENTRAL NEW YORK FROM INTERSTATE 81 AND POINTS EAST. AS THIS WINTER STORM EXITS OFF TO THE NORTHEAST COAST, HIGH PRESSURE WILL BUILD IN FOR MONDAY AND TUESDAY WITH MILDER MORE SPRING LIKE WEATHER. HIGH TEMPERATURES WILL CLIMB INTO THE 40S FOR MONDAY, AND POSSIBLY NEAR 60 FOR TUESDAY. && .NEAR TERM /UNTIL 8 AM THIS MORNING/... 220 AM UPDATE... REMOVED A FEW MORE COUNTIES FROM THE ADVISORY AND WARNING AREA. WILL HOLD THE NEXT UPDATE PACKAGE FOR ANOTHER 1-2 HOURS. HOPEFULLY BY THEN WE CAN LOWER ALL FLAGS. 1210 AM UPDATE... REMOVED ONEIDA, MADISON AND BRADFORD COUNTIES FROM THE ADVISORY AREA. SNOW REMAINS PERSISTENT TO THE SOUTH AND EAST...HOWEVER THE EMBEDDED MODERATE TO HEAVY RETURNS ARE QUICKLY DIMINISHING. THE LATEST HRRR AND WRFARW REFLECTIVITY PROGS HAVE A DECENT HANDLE ON THE CURRENT SCENARIO. HOWEVER THE HRRR MIGHT BE A LITTLE TOO FAST AND AGGRESSIVE WITH TAPERING THE PRECIP OFF OVER THE NEXT HOUR. THE GOOD NEWS SO FAR IS THAT THERE IS LITTLE TO NO FREEZING DRIZZLE SHOWING UP ON THE BACK SIDE OF THE PRECIPITATION. A FEW "UP" WX TYPES HAVE SHOWN UP JUST AFTER THE PRECIP EXITED A STATION, BUT QUICKLY ENDED. SO I WILL HUG THE -FZDZ PTYPE TO THE 15-30 POP AREA BEHIND THE BANDS AND QUICKLY MOVE IT THROUGH. UPDATED AS OF 940 PM... UPGRADED BROOME...SUSQUEHANNA...WYOMING AND NORTHERN WAYNE CO/S TO WINTER STORM WARNING BASED ON SNOWFALL SPOTTER REPORTS. A FEW LOCATIONS IN THESE COUNTIES WILL EXCEED 10 INCHES. MANY REPORTS RECEIVED BETWEEN 5 AND 7 INCHES IN THE WARNING AREA SO WITH PRESENT RADAR TRENDS...BELIEVE MANY AREAS WILL SEE AT LEAST 7 INCHES IN THESE COUNTIES. FARTHER N LESS SNOW WAS REPORTED IN CHENANGO CO AND DELWARE/OTSEGO COUNTIES...TO THE TUNE OF 2-5 INCHES. I CAN SEE A COUPLE MORE INCHES IN THESE PLACES SO WILL STICK WITH ADVY THERE. FARTHER S OF THE WARNING AREA...SNOW IS BECOMING MORE WIDESPREAD BUT NOT CONCENTRATING INTO BANDS. AS THE UPPER LEVEL LOW PULLS AWAY...THE DEFORMATION BAND WILL TAPER DOWN AND WEAKEN...WITH MOST OF THE SNOW TO THE EAST TWD THE POCONOS AND WESTERN CATSKILLS. I THINK WE WILL SEE SNOW AMNTS OF 2-5 INCHES IN THE POCONOS/WESTERN CATSKILLS WITH 1-3 INCHES IN THE VALLEYS. SO WILL CONT ADVY/S IN THE REST OF NE PA AND SULLIVAN CO. PREVIOUS DSCN IS BELOW... WATER VAPOR IMAGERY SHOWS A CLOSED MID TO UPPER LEVEL LOW SPINNING OFF THE NJ COAST. A DEFORMATION ZONE OF LOCALLY HEAVY SNOW HAS SET UP TO THE WEST OF THIS UPPER LEVEL LOW FROM ABT UCA TO NORWICH TO THE CITY OF BINGHAMTON TO AVP. THERE WAS A SECONDARY BAND OF HEAVIER MIXED PRECIP...FROM DELAWARE CO INTO THE POCONOS. WITH MORE SHOWERLY LOOKING PRECIP TO THE S AND E. THIS AREA WAS MAINLY FREEZING RAIN...SLEET AND JUST PLAIN RAIN. THE RAP SHOWS THAT THIS UPPER LEVEL LOW WILL DRIFT EASTWARD BETWEEN 01Z AND 04Z AND THE DEFORMATION ZONE THAT WAS PRESENTLY AT THE WEST EDGE OF THE PRECIP SHIELD WILL WEAKEN. I BELIEVE ANOTHER BAND WILL FORM FARTHER TO THE S AND E AND AFFECT THE WESTERN CATSKILLS INTO PIKE CO/SRN WAYNE BTWN 1 AND 4Z. HOWEVER...THE CYCLONE WAS BECOMING MORE VERTICALLY STACKED AT THIS TIME AND THUS BELIEVE THE HEAVIEST SNOW FROM THIS STORM IN OUR AREA WILL BE OVER. SO HAVE ADJUSTED SNOW AMNTS DOWN A TOUCH FOR SULLIVAN AND PIKE CO/S. FARTHER N AND W...HAVE HAD TO CHASE SNOW AMNTS AS BANDING WAS LEADING TO RAPID SNOW ACCUMULATIONS. BUT AT THE SAME TIME SOME OF THE HIGHER RADAR RETURNS WERE RELATED TO THE MELTING LEVEL AND JUST SLEET AND WET SNOW WAS FALLING WITH LESS ACCUMULATION. SO WE HAVE RELIED HEAVILY ON SPOTTER REPORTS. THANKS TO ALL SPOTTERS WHO HAVE SENT REPORTS IN...THEY HAVE BEEN MOST HELPFUL. WILL CONT WINTER WX ADVY WHERE IT IS IN EFFECT FOR NOW. LIKELY WILL DROP CORTLAND AND TIOGA CO/S BY 9 PM OR SO AS IT LOOKS LIKE THE DEFORMATION BAND HAS HALTED ITS WESTWARD PROGRESS. I WILL WAIT AND SEE ON THIS. REST OF FORECAST AREA TO THE WEST OF THE PRECIP SHIELD WILL BE JUST CLOUDY AND BLUSTERY FOR THE NIGHTTIME HOURS. && .SHORT TERM /8 AM THIS MORNING THROUGH WEDNESDAY/... 320 PM UPDATE... HIPRES WL BUILD IN ON MONDAY AS COASTAL STORM RIDES OFF TO THE NORTHEAST TAKING MOISTURE WITH IT. ONLY LINGERING AFFECT WL BE CLOUD CVR VRY EARLY IN THE MRNG BFR DRY AIR MVS IN FM THE NW. SKIES WL BE MOSUNNY AND TEMPS WL HANDILY RISE INTO THE 40S/NR 50 UNDER STRONG MARCH SUN TOMORROW. 500MB HEIGHTS FOR TUESDAY WILL CLIMB TO NR 567DM WITH S/WV RIDGE BUILDING DIRECTLY OVRHD. GIVEN STRONG MARCH SUN HV GONE ABV GUIDANCE NUMBERS WITH HIGHS IN THE U50S/LWR 60S IN THE VLYS. NO WX IS EXPECTED UNTIL NEXT S/WV APPCHS TUE NGT, SPREADING SHOWERS INTO PORTIONS OF THE AREA MAINLY ACRS NRN ZONES. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... 245 PM UPDATE.. SLIGHTLY COOLER WEATHER BUILDS INTO THE AREA WEDNESDAY NIGHT INTO THURSDAY WHICH WILL RETURN TEMPS CLOSER TO SEASONAL NORMS. THE MAIN FEATURE OF INTEREST IN THE EXTENDED WILL BE THE DEVELOPMENT OF A CLOSED UPPER LOW OVER THE UPPER MIDWEST BY FRIDAY. SOME PRECIPITATION, MAINLY RAIN SHOWERS, MAY TRY TO SNEAK INTO THE SOUTHERN PART OF THE CWA LATE THURSDAY ALONG A BOUNDARY. FOR THE MOST PART THOUGH WE STAY PRECIPITATION FREE UNTIL FRIDAY NIGHT WHEN A FRONT ASSOCIATED WITH THE CLOSED LOW MENTIONED ABOVE, MOVES THROUGH. WE ARE TALKING ALMOST AN ENTIRELY RAIN EVENT BUT SOME ENOUGH COLD AIR MAY REMAIN FOR SOME WET SNOW OVER NORTHERN ONEIDA COUNTY FRIDAY NIGHT. PRECIPITATION ENDS SATURDAY AS OUR REGION GETS INTO A DRY SLOT. BEYOND SATURDAY WE COOL BACK TO BELOW NORMAL FOR THE 2ND HALF OF THE WEEKEND INTO EARLY NEXT WEEK AS THE ACTUAL UPPER LOW MOVES JUST TO OUR NORTH. && .AVIATION /07Z MONDAY THROUGH FRIDAY/... 06Z UPDATE... IMPROVING CONDITIONS AS SYSTEM ALONG THE COAST CONTINUES TO PULL AWAY. SHARP OUTER RIM OF SNOW WILL STILL CAUSE INTERMITTENT IFR SNOW AT KAVP 06Z-08Z...OTHERWISE ONLY DEALING WITH MVFR CIGS ACROSS ALL TERMINALS EARLY THIS MORNING. AIR MASS IS NOT COLD ENOUGH TO GENERATE ADDITIONAL CLOUDS OFF OF LAKE ONTARIO...AND WIND DIRECTION HAS A LOT OF NORTHERLY COMPONENT...THUS EXPECTING SCATTERING OUT OF CIGS TO OCCUR THIS MORNING 12Z-16Z INSTEAD OF THE USUAL LONGER PERSISTING CIGS THAT OFTEN OCCUR BEHIND A SYSTEM. BEHIND THE EXITING RIM OF SNOW...MODELS/SOUNDINGS ARE ACTUALLY TOO MOIST COMPARED TO OBSERVED CIGS...AND THUS I AM NOT EXPECTING IFR CIG AT KBGM AT THIS POINT AS GUIDANCE WOULD SUGGEST. NNW WINDS 10-14 KT WITH GUSTS TO AROUND 20 KTS MUCH OF TODAY...THEN DECOUPLING TO WELL UNDER 10 KTS FROM NE OR VARIABLE THIS EVENING. OUTLOOK... LATE MON NGT THROUGH TUE NGT...VFR. WED/THU/FRI...RESTRICTIONS POSSIBLE IN LIGHT RAIN SOUTHERN TERMINALS WED-THU...ALL TERMINALS THU NGT-FRI. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...WINTER WEATHER ADVISORY UNTIL 8 AM EDT THIS MORNING FOR PAZ044- 047-048-072. WINTER STORM WARNING UNTIL 8 AM EDT THIS MORNING FOR PAZ039- 040-043. NY...WINTER WEATHER ADVISORY UNTIL 8 AM EDT THIS MORNING FOR NYZ062. && $$ SYNOPSIS...DJN NEAR TERM...DJN/DJP SHORT TERM...PVN LONG TERM...HEDEN AVIATION...MDP
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
146 AM EDT MON MAR 31 2014 .SYNOPSIS... A LATE SEASON WINTER STORM THAT WAS CENTERED OFF THE NEW JERSEY COAST WILL SHIFT FARTHER OUT TO SEA OVERNIGHT. ALL THE SNOW AND MIXED PRECIPITATION WILL TAPER OFF LATE TONIGHT. IN THE MEANTIME...TRAVEL WILL BE HAZARDOUS TONIGHT ACROSS MUCH OF NORTHEAST PENNSYLVANIA AND IN CENTRAL NEW YORK FROM INTERSTATE 81 AND POINTS EAST. AS THIS WINTER STORM EXITS OFF TO THE NORTHEAST COAST, HIGH PRESSURE WILL BUILD IN FOR MONDAY AND TUESDAY WITH MILDER MORE SPRING LIKE WEATHER. HIGH TEMPERATURES WILL CLIMB INTO THE 40S FOR MONDAY, AND POSSIBLY NEAR 60 FOR TUESDAY. && .NEAR TERM /UNTIL 8 AM THIS MORNING/... 1210 AM UPDATE... REMOVED ONEIDA, MADISON AND BRADFORD COUNTIES FROM THE ADVISORY AREA. SNOW REMAINS PERSISTENT TO THE SOUTH AND EAST...HOWEVER THE EMBEDDED MODERATE TO HEAVY RETURNS ARE QUICKLY DIMINISHING. THE LATEST HRRR AND WRFARW REFLECTIVITY PROGS HAVE A DECENT HANDLE ON THE CURRENT SCENARIO. HOWEVER THE HRRR MIGHT BE A LITTLE TOO FAST AND AGGRESSIVE WITH TAPERING THE PRECIP OFF OVER THE NEXT HOUR. THE GOOD NEWS SO FAR IS THAT THERE IS LITTLE TO NO FREEZING DRIZZLE SHOWING UP ON THE BACK SIDE OF THE PRECIPITATION. A FEW "UP" WX TYPES HAVE SHOWN UP JUST AFTER THE PRECIP EXITED A STATION, BUT QUICKLY ENDED. SO I WILL HUG THE -FZDZ PTYPE TO THE 15-30 POP AREA BEHIND THE BANDS AND QUICKLY MOVE IT THROUGH. UPDATED AS OF 940 PM... UPGRADED BROOME...SUSQUEHANNA...WYOMING AND NORTHERN WAYNE CO/S TO WINTER STORM WARNING BASED ON SNOWFALL SPOTTER REPORTS. A FEW LOCATIONS IN THESE COUNTIES WILL EXCEED 10 INCHES. MANY REPORTS RECEIVED BETWEEN 5 AND 7 INCHES IN THE WARNING AREA SO WITH PRESENT RADAR TRENDS...BELIEVE MANY AREAS WILL SEE AT LEAST 7 INCHES IN THESE COUNTIES. FARTHER N LESS SNOW WAS REPORTED IN CHENANGO CO AND DELWARE/OTSEGO COUNTIES...TO THE TUNE OF 2-5 INCHES. I CAN SEE A COUPLE MORE INCHES IN THESE PLACES SO WILL STICK WITH ADVY THERE. FARTHER S OF THE WARNING AREA...SNOW IS BECOMING MORE WIDESPREAD BUT NOT CONCENTRATING INTO BANDS. AS THE UPPER LEVEL LOW PULLS AWAY...THE DEFORMATION BAND WILL TAPER DOWN AND WEAKEN...WITH MOST OF THE SNOW TO THE EAST TWD THE POCONOS AND WESTERN CATSKILLS. I THINK WE WILL SEE SNOW AMNTS OF 2-5 INCHES IN THE POCONOS/WESTERN CATSKILLS WITH 1-3 INCHES IN THE VALLEYS. SO WILL CONT ADVY/S IN THE REST OF NE PA AND SULLIVAN CO. PREVIOUS DSCN IS BELOW... WATER VAPOR IMAGERY SHOWS A CLOSED MID TO UPPER LEVEL LOW SPINNING OFF THE NJ COAST. A DEFORMATION ZONE OF LOCALLY HEAVY SNOW HAS SET UP TO THE WEST OF THIS UPPER LEVEL LOW FROM ABT UCA TO NORWICH TO THE CITY OF BINGHAMTON TO AVP. THERE WAS A SECONDARY BAND OF HEAVIER MIXED PRECIP...FROM DELAWARE CO INTO THE POCONOS. WITH MORE SHOWERLY LOOKING PRECIP TO THE S AND E. THIS AREA WAS MAINLY FREEZING RAIN...SLEET AND JUST PLAIN RAIN. THE RAP SHOWS THAT THIS UPPER LEVEL LOW WILL DRIFT EASTWARD BETWEEN 01Z AND 04Z AND THE DEFORMATION ZONE THAT WAS PRESENTLY AT THE WEST EDGE OF THE PRECIP SHIELD WILL WEAKEN. I BELIEVE ANOTHER BAND WILL FORM FARTHER TO THE S AND E AND AFFECT THE WESTERN CATSKILLS INTO PIKE CO/SRN WAYNE BTWN 1 AND 4Z. HOWEVER...THE CYCLONE WAS BECOMING MORE VERTICALLY STACKED AT THIS TIME AND THUS BELIEVE THE HEAVIEST SNOW FROM THIS STORM IN OUR AREA WILL BE OVER. SO HAVE ADJUSTED SNOW AMNTS DOWN A TOUCH FOR SULLIVAN AND PIKE CO/S. FARTHER N AND W...HAVE HAD TO CHASE SNOW AMNTS AS BANDING WAS LEADING TO RAPID SNOW ACCUMULATIONS. BUT AT THE SAME TIME SOME OF THE HIGHER RADAR RETURNS WERE RELATED TO THE MELTING LEVEL AND JUST SLEET AND WET SNOW WAS FALLING WITH LESS ACCUMULATION. SO WE HAVE RELIED HEAVILY ON SPOTTER REPORTS. THANKS TO ALL SPOTTERS WHO HAVE SENT REPORTS IN...THEY HAVE BEEN MOST HELPFUL. WILL CONT WINTER WX ADVY WHERE IT IS IN EFFECT FOR NOW. LIKELY WILL DROP CORTLAND AND TIOGA CO/S BY 9 PM OR SO AS IT LOOKS LIKE THE DEFORMATION BAND HAS HALTED ITS WESTWARD PROGRESS. I WILL WAIT AND SEE ON THIS. REST OF FORECAST AREA TO THE WEST OF THE PRECIP SHIELD WILL BE JUST CLOUDY AND BLUSTERY FOR THE NIGHTTIME HOURS. && .SHORT TERM /8 AM THIS MORNING THROUGH WEDNESDAY/... 320 PM UPDATE... HIPRES WL BUILD IN ON MONDAY AS COASTAL STORM RIDES OFF TO THE NORTHEAST TAKING MOISTURE WITH IT. ONLY LINGERING AFFECT WL BE CLOUD CVR VRY EARLY IN THE MRNG BFR DRY AIR MVS IN FM THE NW. SKIES WL BE MOSUNNY AND TEMPS WL HANDILY RISE INTO THE 40S/NR 50 UNDER STRONG MARCH SUN TOMORROW. 500MB HEIGHTS FOR TUESDAY WILL CLIMB TO NR 567DM WITH S/WV RIDGE BUILDING DIRECTLY OVRHD. GIVEN STRONG MARCH SUN HV GONE ABV GUIDANCE NUMBERS WITH HIGHS IN THE U50S/LWR 60S IN THE VLYS. NO WX IS EXPECTED UNTIL NEXT S/WV APPCHS TUE NGT, SPREADING SHOWERS INTO PORTIONS OF THE AREA MAINLY ACRS NRN ZONES. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... 245 PM UPDATE.. SLIGHTLY COOLER WEATHER BUILDS INTO THE AREA WEDNESDAY NIGHT INTO THURSDAY WHICH WILL RETURN TEMPS CLOSER TO SEASONAL NORMS. THE MAIN FEATURE OF INTEREST IN THE EXTENDED WILL BE THE DEVELOPMENT OF A CLOSED UPPER LOW OVER THE UPPER MIDWEST BY FRIDAY. SOME PRECIPITATION, MAINLY RAIN SHOWERS, MAY TRY TO SNEAK INTO THE SOUTHERN PART OF THE CWA LATE THURSDAY ALONG A BOUNDARY. FOR THE MOST PART THOUGH WE STAY PRECIPITATION FREE UNTIL FRIDAY NIGHT WHEN A FRONT ASSOCIATED WITH THE CLOSED LOW MENTIONED ABOVE, MOVES THROUGH. WE ARE TALKING ALMOST AN ENTIRELY RAIN EVENT BUT SOME ENOUGH COLD AIR MAY REMAIN FOR SOME WET SNOW OVER NORTHERN ONEIDA COUNTY FRIDAY NIGHT. PRECIPITATION ENDS SATURDAY AS OUR REGION GETS INTO A DRY SLOT. BEYOND SATURDAY WE COOL BACK TO BELOW NORMAL FOR THE 2ND HALF OF THE WEEKEND INTO EARLY NEXT WEEK AS THE ACTUAL UPPER LOW MOVES JUST TO OUR NORTH. && .AVIATION /06Z MONDAY THROUGH FRIDAY/... 06Z UPDATE... IMPROVING CONDITIONS AS SYSTEM ALONG THE COAST CONTINUES TO PULL AWAY. SHARP OUTER RIM OF SNOW WILL STILL CAUSE INTERMITTENT IFR SNOW AT KAVP 06Z-08Z...OTHERWISE ONLY DEALING WITH MVFR CIGS ACROSS ALL TERMINALS EARLY THIS MORNING. AIR MASS IS NOT COLD ENOUGH TO GENERATE ADDITIONAL CLOUDS OFF OF LAKE ONTARIO...AND WIND DIRECTION HAS A LOT OF NORTHERLY COMPONENT...THUS EXPECTING SCATTERING OUT OF CIGS TO OCCUR THIS MORNING 12Z-16Z INSTEAD OF THE USUAL LONGER PERSISTING CIGS THAT OFTEN OCCUR BEHIND A SYSTEM. BEHIND THE EXITING RIM OF SNOW...MODELS/SOUNDINGS ARE ACTUALLY TOO MOIST COMPARED TO OBSERVED CIGS...AND THUS I AM NOT EXPECTING IFR CIG AT KBGM AT THIS POINT AS GUIDANCE WOULD SUGGEST. NNW WINDS 10-14 KT WITH GUSTS TO AROUND 20 KTS MUCH OF TODAY...THEN DECOUPLING TO WELL UNDER 10 KTS FROM NE OR VARIABLE THIS EVENING. OUTLOOK... LATE MON NGT THROUGH TUE NGT...VFR. WED/THU/FRI...RESTRICTIONS POSSIBLE IN LIGHT RAIN SOUTHERN TERMINALS WED-THU...ALL TERMINALS THU NGT-FRI. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...WINTER WEATHER ADVISORY UNTIL 8 AM EDT THIS MORNING FOR PAZ044- 047-048-072. WINTER STORM WARNING UNTIL 8 AM EDT THIS MORNING FOR PAZ039- 040-043. NY...WINTER WEATHER ADVISORY UNTIL 8 AM EDT THIS MORNING FOR NYZ045- 046-057-062. WINTER STORM WARNING UNTIL 8 AM EDT THIS MORNING FOR NYZ056. && $$ SYNOPSIS...DJN NEAR TERM...DJN/DJP SHORT TERM...PVN LONG TERM...HEDEN AVIATION...MDP
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1216 AM EDT MON MAR 31 2014 .SYNOPSIS... A LATE SEASON WINTER STORM THAT WAS CENTERED OFF THE NEW JERSEY COAST WILL SHIFT FARTHER OUT TO SEA OVERNIGHT. ALL THE SNOW AND MIXED PRECIPITATION WILL TAPER OFF LATE TONIGHT. IN THE MEANTIME...TRAVEL WILL BE HAZARDOUS TONIGHT ACROSS MUCH OF NORTHEAST PENNSYLVANIA AND IN CENTRAL NEW YORK FROM INTERSTATE 81 AND POINTS EAST. AS THIS WINTER STORM EXITS OFF TO THE NORTHEAST COAST, HIGH PRESSURE WILL BUILD IN FOR MONDAY AND TUESDAY WITH MILDER MORE SPRING LIKE WEATHER. HIGH TEMPERATURES WILL CLIMB INTO THE 40S FOR MONDAY, AND POSSIBLY NEAR 60 FOR TUESDAY. && .NEAR TERM /UNTIL 8 AM THIS MORNING/... 1210 AM UPDATE... REMOVED ONEIDA, MADISON AND BRADFORD COUNTIES FROM THE ADVISORY AREA. SNOW REMAINS PERSISTENT TO THE SOUTH AND EAST...HOWEVER THE EMBEDDED MODERATE TO HEAVY RETURNS ARE QUICKLY DIMINISHING. THE LATEST HRRR AND WRFARW REFLECTIVITY PROGS HAVE A DECENT HANDLE ON THE CURRENT SCENARIO. HOWEVER THE HRRR MIGHT BE A LITTLE TOO FAST AND AGGRESSIVE WITH TAPERING THE PRECIP OFF OVER THE NEXT HOUR. THE GOOD NEWS SO FAR IS THAT THERE IS LITTLE TO NO FREEZING DRIZZLE SHOWING UP ON THE BACK SIDE OF THE PRECIPITATION. A FEW "UP" WX TYPES HAVE SHOWN UP JUST AFTER THE PRECIP EXITED A STATION, BUT QUICKLY ENDED. SO I WILL HUG THE -FZDZ PTYPE TO THE 15-30 POP AREA BEHIND THE BANDS AND QUICKLY MOVE IT THROUGH. UPDATED AS OF 940 PM... UPGRADED BROOME...SUSQUEHANNA...WYOMING AND NORTHERN WAYNE CO/S TO WINTER STORM WARNING BASED ON SNOWFALL SPOTTER REPORTS. A FEW LOCATIONS IN THESE COUNTIES WILL EXCEED 10 INCHES. MANY REPORTS RECEIVED BETWEEN 5 AND 7 INCHES IN THE WARNING AREA SO WITH PRESENT RADAR TRENDS...BELIEVE MANY AREAS WILL SEE AT LEAST 7 INCHES IN THESE COUNTIES. FARTHER N LESS SNOW WAS REPORTED IN CHENANGO CO AND DELWARE/OTSEGO COUNTIES...TO THE TUNE OF 2-5 INCHES. I CAN SEE A COUPLE MORE INCHES IN THESE PLACES SO WILL STICK WITH ADVY THERE. FARTHER S OF THE WARNING AREA...SNOW IS BECOMING MORE WIDESPREAD BUT NOT CONCENTRATING INTO BANDS. AS THE UPPER LEVEL LOW PULLS AWAY...THE DEFORMATION BAND WILL TAPER DOWN AND WEAKEN...WITH MOST OF THE SNOW TO THE EAST TWD THE POCONOS AND WESTERN CATSKILLS. I THINK WE WILL SEE SNOW AMNTS OF 2-5 INCHES IN THE POCONOS/WESTERN CATSKILLS WITH 1-3 INCHES IN THE VALLEYS. SO WILL CONT ADVY/S IN THE REST OF NE PA AND SULLIVAN CO. PREVIOUS DSCN IS BELOW... WATER VAPOR IMAGERY SHOWS A CLOSED MID TO UPPER LEVEL LOW SPINNING OFF THE NJ COAST. A DEFORMATION ZONE OF LOCALLY HEAVY SNOW HAS SET UP TO THE WEST OF THIS UPPER LEVEL LOW FROM ABT UCA TO NORWICH TO THE CITY OF BINGHAMTON TO AVP. THERE WAS A SECONDARY BAND OF HEAVIER MIXED PRECIP...FROM DELAWARE CO INTO THE POCONOS. WITH MORE SHOWERLY LOOKING PRECIP TO THE S AND E. THIS AREA WAS MAINLY FREEZING RAIN...SLEET AND JUST PLAIN RAIN. THE RAP SHOWS THAT THIS UPPER LEVEL LOW WILL DRIFT EASTWARD BETWEEN 01Z AND 04Z AND THE DEFORMATION ZONE THAT WAS PRESENTLY AT THE WEST EDGE OF THE PRECIP SHIELD WILL WEAKEN. I BELIEVE ANOTHER BAND WILL FORM FARTHER TO THE S AND E AND AFFECT THE WESTERN CATSKILLS INTO PIKE CO/SRN WAYNE BTWN 1 AND 4Z. HOWEVER...THE CYCLONE WAS BECOMING MORE VERTICALLY STACKED AT THIS TIME AND THUS BELIEVE THE HEAVIEST SNOW FROM THIS STORM IN OUR AREA WILL BE OVER. SO HAVE ADJUSTED SNOW AMNTS DOWN A TOUCH FOR SULLIVAN AND PIKE CO/S. FARTHER N AND W...HAVE HAD TO CHASE SNOW AMNTS AS BANDING WAS LEADING TO RAPID SNOW ACCUMULATIONS. BUT AT THE SAME TIME SOME OF THE HIGHER RADAR RETURNS WERE RELATED TO THE MELTING LEVEL AND JUST SLEET AND WET SNOW WAS FALLING WITH LESS ACCUMULATION. SO WE HAVE RELIED HEAVILY ON SPOTTER REPORTS. THANKS TO ALL SPOTTERS WHO HAVE SENT REPORTS IN...THEY HAVE BEEN MOST HELPFUL. WILL CONT WINTER WX ADVY WHERE IT IS IN EFFECT FOR NOW. LIKELY WILL DROP CORTLAND AND TIOGA CO/S BY 9 PM OR SO AS IT LOOKS LIKE THE DEFORMATION BAND HAS HALTED ITS WESTWARD PROGRESS. I WILL WAIT AND SEE ON THIS. REST OF FORECAST AREA TO THE WEST OF THE PRECIP SHIELD WILL BE JUST CLOUDY AND BLUSTERY FOR THE NIGHTTIME HOURS. && .SHORT TERM /8 AM THIS MORNING THROUGH WEDNESDAY/... 320 PM UPDATE... HIPRES WL BUILD IN ON MONDAY AS COASTAL STORM RIDES OFF TO THE NORTHEAST TAKING MOISTURE WITH IT. ONLY LINGERING AFFECT WL BE CLOUD CVR VRY EARLY IN THE MRNG BFR DRY AIR MVS IN FM THE NW. SKIES WL BE MOSUNNY AND TEMPS WL HANDILY RISE INTO THE 40S/NR 50 UNDER STRONG MARCH SUN TOMORROW. 500MB HEIGHTS FOR TUESDAY WILL CLIMB TO NR 567DM WITH S/WV RIDGE BUILDING DIRECTLY OVRHD. GIVEN STRONG MARCH SUN HV GONE ABV GUIDANCE NUMBERS WITH HIGHS IN THE U50S/LWR 60S IN THE VLYS. NO WX IS EXPECTED UNTIL NEXT S/WV APPCHS TUE NGT, SPREADING SHOWERS INTO PORTIONS OF THE AREA MAINLY ACRS NRN ZONES. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... 245 PM UPDATE.. SLIGHTLY COOLER WEATHER BUILDS INTO THE AREA WEDNESDAY NIGHT INTO THURSDAY WHICH WILL RETURN TEMPS CLOSER TO SEASONAL NORMS. THE MAIN FEATURE OF INTEREST IN THE EXTENDED WILL BE THE DEVELOPMENT OF A CLOSED UPPER LOW OVER THE UPPER MIDWEST BY FRIDAY. SOME PRECIPITATION, MAINLY RAIN SHOWERS, MAY TRY TO SNEAK INTO THE SOUTHERN PART OF THE CWA LATE THURSDAY ALONG A BOUNDARY. FOR THE MOST PART THOUGH WE STAY PRECIPITATION FREE UNTIL FRIDAY NIGHT WHEN A FRONT ASSOCIATED WITH THE CLOSED LOW MENTIONED ABOVE, MOVES THROUGH. WE ARE TALKING ALMOST AN ENTIRELY RAIN EVENT BUT SOME ENOUGH COLD AIR MAY REMAIN FOR SOME WET SNOW OVER NORTHERN ONEIDA COUNTY FRIDAY NIGHT. PRECIPITATION ENDS SATURDAY AS OUR REGION GETS INTO A DRY SLOT. BEYOND SATURDAY WE COOL BACK TO BELOW NORMAL FOR THE 2ND HALF OF THE WEEKEND INTO EARLY NEXT WEEK AS THE ACTUAL UPPER LOW MOVES JUST TO OUR NORTH. && .AVIATION /04Z MONDAY THROUGH FRIDAY/... 730 PM UPDATE... COMPLEX AVIATION FORECAST THROUGH TONIGHT. GRADUAL IMPROVEMENT MONDAY MORNING. VFR MON AFTN ON. IN GENERAL IFR CIGS AT ITH AND BGM WILL CONTINUE. POSSIBLE IFR AT AVP AND RME IN SNOW UP TO 3Z. SHARP LINE OF SNOW FROM JUST EAST OF RME AND BGM. THIS LINE SLOWING BUT MAY MAKE IT TO BOTH SITES THIS EVE WITH IFR VSBYS. AREA OF SNOW ALSO OVER AVP CONTINUING INTO THE OVERNIGHT BEFORE DYING IN PLACE. MVFR CIGS WITH VSBYS IFR AND MVFR AVP. CIGS WILL REMAIN THE SAME ALL NIGHT BUT AS SNOW ENDS VSBYS WILL IMPROVE TO VFR. AT SYR/ELM/RME MVFR CIGS WILL CONTINUE TONIGHT WITH VFR VSBYS. AT ITH/BGM IFR CIGS CONTINUE ALL NIGHT WITH VFR VSBYS. BGM DUE TO ELEVATION AND ITH DUE TO FETCH OFF CAYUGA LAKE. AFTER 10Z SLOW IMPROVEMENT TO MVFR THEN TO VFR BY 16Z. NORTH WINDS 10 T0 15 KTS WITH HIGHER GUSTS AT BGM AND AVP INTO MONDAY. OUTLOOK... MON NGT THROUGH WED NGT...MAINLY VFR. THUR/FRI...RESTRICTIONS POSSIBLE IN LIGHT RAIN. && .HYDROLOGY... 8 PM UPDATE... FLOOD WATCH CONTINUES ACROSS THE SOUTH AND EAST. CURRENT PRECIP HAS CHANGED TO SNOW AND SLEET. RUNOFF SHOULD BE CUTTING OFF SOON. THIS DUE TO TEMPERATURES AROUND FREEZING AND PRECIP IN FROZEN FORM. MAY BE ABLE TO DROP THE WATCH BY MIDNIGHT. CURRENT FLOODING IS NINEMILE CREEK AT LAKELAND IN ONONDAGA COUNTY AND TIOUGHNIOGA RIVER AT CORTLAND IN CORTLAND COUNTY. BOTH SHOULD REMAIN ABOVE FLOOD STAGE THIS EVENING THEN FALL BELOW MONDAY. NO OTHER POINTS ARE EXPECTED TO FLOOD NOW. NO REPORTS OF ICE JAMS. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...WINTER WEATHER ADVISORY UNTIL 8 AM EDT THIS MORNING FOR PAZ044- 047-048-072. WINTER STORM WARNING UNTIL 8 AM EDT THIS MORNING FOR PAZ039- 040-043. NY...WINTER WEATHER ADVISORY UNTIL 8 AM EDT THIS MORNING FOR NYZ045- 046-057-062. WINTER STORM WARNING UNTIL 8 AM EDT THIS MORNING FOR NYZ056. && $$ SYNOPSIS...DJN NEAR TERM...DJN/DJP SHORT TERM...PVN LONG TERM...HEDEN AVIATION...TAC HYDROLOGY...
AREA FORECAST DISCUSSION
NWS BISMARCK ND
122 AM CDT MON MAR 31 2014 .UPDATE... ISSUED AT 122 AM CDT MON MAR 31 2014 THE COUNTIES THAT WERE PREVIOUSLY IN THE WINTER STORM WARNING HAVE BEEN UPGRADED TO A BLIZZARD WARNING. THE DRY SLOT ACROSS THE FAR SOUTH CENTRAL AND JAMES RIVER VALLEY IS LIKELY TO REMAIN IN PLACE AT LEAST THROUGH 10-12 UTC FOLLOWING THE 04/05 UTC RAP AND HRRR. GIVEN THE IMPACTS OF THE DRY SLOT AND THUS A SLIGHTLY SLOWER EASTWARD PROGRESSION OF THE BAND EXPECTED INTO MONDAY...SNOWFALL ACCUMULATIONS HAVE BEEN INCREASED SOUTHWEST...SOUTH CENTRAL AND INTO THE UPPER JAMES RIVER VALLEY...AND DECREASED FOR THE JAMES RIVER VALLEY FOR JAMESTOWN SOUTH. SEE THE LATEST WSW STATEMENT FOR DETAILS. UPDATE ISSUED AT 1007 PM CDT SUN MAR 30 2014 AGAIN NO SIGNIFICANT UPDATES THIS EVENING. ONLY SOME MINOR ADJUSTMENTS TO LOWER POPS ACROSS THE FAR SOUTH CENTRAL FOR A COUPLE HOURS LATE THIS EVENING. ALREADY REPORTS OF UP TO 4 INCHES OF SNOW ACROSS THE FAR WEST IN BILLINGS AND GOLDEN VALLEY COUNTIES. VERY STRONG FORCING IS POISED TO MOVE INTO WESTERN NORTH DAKOTA IN THE NEXT FEW HOURS. THIS WILL COMBINE WITH STRONG COLD ADVECTION DROPPING SOUTH AND PRODUCE SNOW AMOUNTS OF AROUND AN INCH PER HOUR FROM AROUND BISMARCK WEST TO THE MONTANA BORDER. THIS AREA WILL CONTINUE TO WORD EASTWARD OVERNIGHT...INCREASING SNOW AMOUNTS INTO CENTRAL AND EASTERN NORTH DAKOTA LATE TONIGHT. WILL FRESHEN UP AND SEND OUT TEXT PRODUCTS SHORTLY. UPDATE ISSUED AT 726 PM CDT SUN MAR 30 2014 NO SIGNIFICANT UPDATES TO THE EARLY EVENING FORECAST OTHER THAN POPULATING WITH THE LATEST SENSIBLE WEATHER OBSERVATIONS. LIGHT RAIN IS CHANGING TO LIGHT SNOW OVER WESTERN NORTH DAKOTA AT THIS TIME...WITH LIGHT RAIN MOVING INTO CENTRAL NORTH DAKOTA. EXPECT AREAL COVERAGE TO CONTINUE TO INCREASE AS WE GO THROUGH THE EVENING. NO CHANGES TO CURRENT HEADLINES. && .SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT) ISSUED AT 440 PM CDT SUN MAR 30 2014 HAVE ADJUSTED THE SHORT TERM PERIOD TO TAKE THE STORM TO ITS FINISH. MODELS ARE ALL LEANING CLOSER TO THE ECMWF SOLUTION. THIS BRINGS THE SYSTEM FARTHER NORTH THAN EARLIER EXPECTED AND WITH STRONGER DYNAMICS OVER THE FORECAST AREA FOR HIGHER SNOW AMOUNTS...AND STRONGER WIND IN A TIGHTER GRADIENT. WILL EXPECT THIS TO BE A DANGEROUS STORM WITH VERY SIGNIFICANT IMPACTS TO TRAVEL...COMMERCE...AND PUBLIC SAFETY...FOR THOSE AREAS IN THE BLIZZARD WARNING...BASICALLY THE SOUTHERN HALF OF THE FORECAST AREA. THROUGH THE DAY HAVE EXPANDED THE BLIZZARD WARNING TO THE SOUTHWEST...AND THE WINTER STORM WARNING AND WINTER WEATHER ADVISORY TO THE NORTHEAST. RAIN IN THE SOUTHWEST WILL CHANGE TO SNOW AFTER 10 PM CDT AND SPREAD NORTHEAST. BY DAYBREAK ALL AREAS SHOULD BE SNOWING WITH INCREASING WIND. STORM IS SLOWER TO WIND DOWN. BY MONDAY AFTERNOON SNOW ENDS IN THE NORTHWEST. IT SHOULD BE OUT OF THE FORECAST AREA...JAMESTOWN... SHORTLY AFTER MIDNIGHT MONDAY NIGHT. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 440 PM CDT SUN MAR 30 2014 TUESDAY WILL BE A QUIETER DAY BEHIND MONDAYS DEPARTING WINTER STORM AS A ZONAL FLOW DEVELOPS. A WEAK SHORTWAVE IS FORECAST TO SLIDE THROUGH SOUTHWESTERN NORTH DAKOTA. THIS COULD PRODUCE A LITTLE LIGHT SNOW IN THE SOUTHWEST AND HAVE MAINTAINED THIS IN THE GRIDDED DATA. ANOTHER SOUTHWEST LOW WILL TAKE SHAPE AND BEGIN TO LIFT INTO THE CENTRAL/NORTHERN HIGH PLAINS BY MID TO LATE WEEK. UNCERTAINTY WITH THE TRACK OF SYSTEM AS THE GFS KEEPS THIS SYSTEM MAINLY SOUTH OF NORTH DAKOTA. THE ECMWF/GEM SHIFT THE INCOMING UPPER LOW CLOSER TO NORTH DAKOTA AND HAVE A GREATER AREAL COVERAGE OF SNOW THURSDAY NIGHT INTO FRIDAY. WILL NOT DEVIATE FROM THE ALLBLEND AT THIS TIME WHICH CAPTURES A CHANCE OF SNOW WEDNESDAY THROUGH FRIDAY. WILL CONTINUE TO MONITOR THIS SCENARIO. ALTHOUGH NOT EXPECTING ANY SIGNIFICANT STORMS OVER THE WEEKEND...THERE ARE A COUPLE OF DISTURBANCES THAT ARE FORECAST TO SLIDE THROUGH BUT NOTHING SIGNIFICANT. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 122 AM CDT MON MAR 31 2014 A STRONG STORM SYSTEM WILL IMPACT ALL OF WESTERN AND CENTRAL NORTH DAKOTA WITH WIDESPREAD IFR-VLIFR CONDITIONS IN SNOW AND BLOWING SNOW. KISN AND KMOT WILL EXPERIENCE THE LEAST IMPACTS WITH LESS WINDS...AND REMAINING NORTH OF THE HEAVIEST SNOW. KDIK...KBIS AND KJMS WILL EXPERIENCE THE GREATEST IMPACTS WITH EXTENDED PERIODS OF IFR-LIFR CONDITIONS IN SNOW AND BLOWING SNOW. CONDITIONS WILL IMPROVE FROM WEST TO EAST MONDAY WITH KJMS REMAINING IN BLIZZARD CONDITIONS INTO EARLY MONDAY EVENING. && .BIS WATCHES/WARNINGS/ADVISORIES... BLIZZARD WARNING UNTIL 7 PM CDT /6 PM MDT/ THIS EVENING FOR NDZ013-019>022-034-035-042-045-046. BLIZZARD WARNING UNTIL 4 PM CDT /3 PM MDT/ THIS AFTERNOON FOR NDZ018-031>033-040-041-043-044. WINTER WEATHER ADVISORY UNTIL 4 PM CDT THIS AFTERNOON FOR NDZ010- 017. WINTER WEATHER ADVISORY UNTIL 7 PM CDT THIS EVENING FOR NDZ005- 011-012. BLIZZARD WARNING UNTIL 1 AM CDT TUESDAY FOR NDZ023-025-036-037- 047-048-050-051. && $$ UPDATE...AYD SHORT TERM...JPM LONG TERM...KS AVIATION...AYD
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1202 AM CDT MON MAR 31 2014 .UPDATE... ISSUED AT 1201 PM CDT SUN MAR 30 2014 THE MODELS HAVE BEEN TRENDING WITH A MORE NORTHWARD SOLUTION WITH THE 00Z NAM/GFS AND LATEST RAP AND HRRR RUNS. THE FARTHEST NORTH MODEL WOULD PUT OUR NORTHWESTERN CWA MORE IN THE CROSSFIRE FOR THE HEAVIEST SNOW AND OUR SOUTH WOULD MISS OUT ON MOST OF THE SNOW. HOWEVER...THE TRACK OF THE GREATEST HEIGHT FALLS IN THE MODELS DO NOT SEEM TO FIT A MORE NORTHERN SOLUTION. WILL COMPROMISE AND GO MORE TOWARDS THE NAM WHICH IS NOT AS FAR NORTH AS THE GFS AND THE SHORT RANGE MODELS. SOUTHERN COUNTIES HAVE BEEN STAYING ABOVE FREEZING SO WE PROBABLY WILL NOT SEE A SWITCH OVER TO SNOW UNTIL FAIRLY LATE IN THE GAME. CUT SNOW AMOUNTS A BIT OVER OUR SOUTHERN COUNTIES...BUT WITH THE CHANCE OF SOME MIXED PRECIP ALONG WITH WINDS AND BLOWING SNOW...BLIZZARD AND WINTER WARNINGS STILL LOOK GOOD. UPDATE ISSUED AT 944 PM CDT SUN MAR 30 2014 ADJUSTED POPS SOMEWHAT FOR A SLIGHTLY SLOWER PROGRESSION EASTWARD OF THE CATEGORICAL PERCENTAGES. DEVILS LAKE HAS HAD SOME RADAR RETURNS FOR A WHILE BUT JUST NOW STARTED GETTING SOME SNOW. THINK THAT IT WILL BE A WHILE BEFORE OUR NORTHEASTERN COUNTIES SEE MUCH...BUT MOST OF THE NORTHERN PART OF THE CWA WILL SEE SOME SNOW DEVELOPING BY 06 AND 09Z. THE BEST QPF VALUES CONTINUE TO BE LATER ON IN THE AFTERNOON AS THE SYSTEM WRAPS UP. MADE ONLY MINOR ADJUSTMENTS TO SNOW TOTALS AT THIS POINT AND WILL KEEP THE HEADLINES WE HAVE GOING. UPDATE ISSUED AT 639 PM CDT SUN MAR 30 2014 MADE ONLY MINOR TWEAKS TO THE GOING FORECAST AS WE ARE IN A HOLDING PATTERN UNTIL THE STORM SYSTEM BEGINS MOVING INTO THE AREA. MAY HAVE TO MAKE SOME ADJUSTMENTS TO THE TIMING OR PLACEMENT OF POPS BUT WILL WAIT FOR THE BAND TO BEGIN DEVELOPING WHICH SHOULD BE AROUND 03Z ACCORDING TO SHORT RANGE MODELS. && .SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT) ISSUED AT 325 PM CDT SUN MAR 30 2014 MAIN FORECAST CHALLENGE WILL BE THE STORM SYSTEM FOR LATER TONIGHT INTO EARLY TUESDAY. 12Z MODELS ARE IN MUCH BETTER AGREEMENT OVERALL WITH THIS SYSTEM WHICH INCREASES CONFIDENCE FOR THE WARNING PHASE. AS OF MID TO LATE AFTERNOON TEMPS HAD CLIMBED INTO THE MID TO UPPER 50S ACROSS THE SOUTHWEST FA BUT HAVE MAINTAINED THE MID 30S IN THE NORTHWEST. WINDS HAVE PRETTY MUCH SHIFTED TO A NORTHERLY DIRECTION NOW ACROSS ALL BUT THE FAR EASTERN FA. ALSO SEEING SFC DEW POINTS IN THE MID 30S ACROSS THE SOUTHERN FA WITH SOME 40S IN SOUTHWEST MN. SEEING CLOUD COVER THICKENING A BIT ACROSS THE AREA BUT STILL SOMEWHAT THIN ALLOWING SOME SUN THRU. THIS IS THE CALM BEFORE THE STORM. THICKER CLOUDS AND MORE SUBSTANTIAL ECHOES ARE SHOWING UP OVER EASTERN MT/WESTERN ND NOW. MODELS SLOWLY BRING SOME OF THIS NORTHEAST INTO MAINLY THE KDVL REGION LATER THIS EVENING. TEMPS WILL STAY MILD THIS EVENING AND EVEN AFTER MIDNIGHT...ESPECIALLY IN THE SOUTHERN AND EASTERN FA. THEREFORE AS THIS BAND OF PCPN EXPANDS ESPECIALLY AFTER MIDNIGHT PCPN TYPE COULD BECOME MORE OF AN ISSUE. THEREFORE THINKING SOME FORM OF MIXED PCPN MAY FALL LATE THIS EVENING INTO THE OVERNIGHT HOURS MAINLY ACROSS THE SOUTHERN AND EASTERN FA WHERE TEMPS ARE A LITTLE MILDER. NOT THINKING THIS WILL BE THE MAIN FORECAST ISSUE THOUGH...BUT WOULD DEFINITELY ADD TO THE PROBLEMS ASSOCIATED WITH THIS SYSTEM. THINKING THE SNOW WILL BEGIN TO GET HEAVIER AFTER MIDNIGHT ACROSS THE KDVL REGION INTO THE NORTHERN RED RIVER VALLEY. NORTHEAST WINDS WILL ALSO BEGIN TO CRANK UP BETWEEN 06Z AND 12Z FOR THIS AREA SO WILL GO AHEAD AND ISSUE A BLIZZARD WARNING FOR THIS AREA REPLACING THE BLIZZARD WATCH. AS THE SNOW BAND MOVES INTO NORTHWEST MN EAST OF THE VALLEY WINDS SHOULD NOT BE AS BIG OF A PROBLEM. WILL ISSUE A WINTER STORM WARNING FOR THIS AREA. MAIN QUESTION WILL CONTINUE TO BE WARM TEMPS ACROSS SOUTHEAST ND INTO WEST CENTRAL MN. THIS WILL AFFECT SNOW TOTALS AND EXACTLY WHEN BLIZZARD CONDITIONS MAY GET UNDER WAY. THINK THERE IS STILL ENOUGH UNCERTAINTY FOR THIS AREA TO KEEP THE BLIZZARD WATCH GOING THERE. FOR THE FARGO MOORHEAD AREA CONDITIONS WILL PROBABLY DETERIORATE ON MONDAY MORNING. THEREFORE WENT WITH A BLIZZARD WARNING FOR THAT AREA STARTING AT 12Z MONDAY. THIS IS THE TYPE OF SYSTEM THOUGH THAT THERE COULD INITIALLY BE LARGE VARIATIONS IN CONDITIONS FROM ONE PORTION OF A COUNTY TO ANOTHER. BIGGEST QUESTION MARK IS WHAT TO DO WITH EASTERN OTTER TAIL AND WADENA COUNTIES. AFTER COORDINATING WITH ADJACENT OFFICES WENT WITH A WINTER WEATHER ADVISORY. AS FAR AS SNOW TOTALS THIS IS DEFINITELY A CHALLENGE. REALLY THIS IS FORECASTING A RECORD TYPE EVENT SO HARD TO USE MUCH PERSONAL EXPERIENCE. WENT WITH A BAND OF 20 OR SO INCHES FROM COOPERSTOWN TO KGFK TO THE LAKE OF THE WOODS. MOST UNCERTAINTY MAY BE ACROSS SOUTHEAST ND AND WEST CENTRAL MN. WITH MODELS TRENDING NORTHWARD THE PAST FEW RUNS AND SLIGHT SHIFT COULD MAKE A BIG DIFFERENCE. LEFT THE EXPIRATION TIME AT 12Z TUE ALTHOUGH THERE COULD STILL BE SOMETHING LEFT IN THE EASTERN FA. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 325 PM CDT SUN MAR 30 2014 LEFT THE TUE AFTERNOON INTO WED TIME FRAME DRY. TEMPS WILL DEPEND ON SNOW AMOUNTS FROM THE MON/TUE STORM. WEDNESDAY NIGHT-SUNDAY...12Z MODELS ALL INDICATE A STRONG SYSTEM WILL PROPAGATE ACROSS THE CENTRAL CONUS AROUND FRIDAY. HOWEVER...THE MODELS DIFFER WITH EXACTLY HOW FAR NORTH THIS SYSTEM WILL TRACK. THE GEM AND ECMWF BRING HEAVY SNOW AND STRONG WINDS INTO AT LEAST THE SOUTHERN FA...WHILE THE GFS KEEPS ALL SENSIBLE WEATHER TO THE SOUTH. KEPT THE IDEA OF LOWER POPS ACROSS THE SOUTHERN FA FOR THIS SYSTEM. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 1201 PM CDT SUN MAR 30 2014 MVFR CIGS HAVE BEEN A BIT SLOWER TO MOVE INTO KGFK AND KTVF...SO SLOWED THE DECREASE OUT OF VFR CIGS FROM PREVIOUS TAF ISSUANCE. OTHERWISE KEPT THE CONDITIONS FALLING INTO THE GUTTER BY TOMORROW MORNING WITH SNOW AND BLOWING SNOW. THERE COULD EVEN BE SOME FZRA AT KFAR AND KBJI AT SOME POINT. HAVE THE CONDITIONS REMAINING AT 1/2SM WITH LOW SIGS THROUGH MUCH OF THE DAY ON MONDAY WITH ONLY SOME MINOR RECOVERY MONDAY NIGHT. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...BLIZZARD WATCH FROM MONDAY AFTERNOON THROUGH TUESDAY MORNING FOR NDZ052-053. BLIZZARD WARNING UNTIL 7 AM CDT TUESDAY FOR NDZ006>008-014>016- 024-026>030-038-054. BLIZZARD WARNING FROM 7 AM MONDAY TO 7 AM CDT TUESDAY FOR NDZ039- 049. MN...BLIZZARD WATCH FROM MONDAY AFTERNOON THROUGH TUESDAY MORNING FOR MNZ029. WINTER STORM WARNING FROM 7 AM MONDAY TO 7 AM CDT TUESDAY FOR MNZ015>017-022>024-027-028. BLIZZARD WATCH FROM MONDAY EVENING THROUGH TUESDAY MORNING FOR MNZ030-040. BLIZZARD WARNING UNTIL 7 AM CDT TUESDAY FOR MNZ001-004-007. WINTER STORM WARNING UNTIL 7 AM CDT TUESDAY FOR MNZ005-006-008- 009-013-014. BLIZZARD WARNING FROM 7 AM MONDAY TO 7 AM CDT TUESDAY FOR MNZ002- 003. WINTER WEATHER ADVISORY FROM 7 PM MONDAY TO 7 AM CDT TUESDAY FOR MNZ031-032. && $$ UPDATE...JR SHORT TERM...GODON LONG TERM...GODON/TG AVIATION...JR
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
342 AM CDT MON MAR 31 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 342 AM CDT MON MAR 31 2014 A VARIETY OF IMPACTS EXIST IN THE SHORT TERM FROM AN APPROACHING NEGATIVELY TILTED SHORTWAVE. HAVE TRIED TO EXPLAIN THEM THE BEST IN AN ORGANIZED FASHION BELOW. CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS SHOWED A DEEP TROUGH JUST OFF THE U.S. WEST COAST...A NEGATIVELY TILTED VIGOROUS SHORTWAVE OVER NORTHEAST COLORADO...AND RIDGING FROM LOUISIANA INTO MICHIGAN. PLENTIFUL UPPER LEVEL MOISTURE ON WATER VAPOR WAS STREAMING FROM THE CENTRAL PLAINS INTO THE FORECAST AREA AHEAD OF THE VIGOROUS SHORTWAVE...MANIFESTING ITSELF AS SCT-BKN CIRRUS. BELOW THESE CLOUDS...A DRY AIRMASS EXISTS AS SEEN ON A 00Z 700MB AND 850MB RAOB PLOT...WITH DEWPOINT DEPRESSIONS OF 10-20C FROM THE FORECAST AREA SOUTHWEST THROUGH THE CENTRAL PLAINS. SURFACE DEWPOINTS ARE INCREASING IN THE SAME AREA...HOWEVER...NOW ABOUT 5-15 DEGREES HIGHER. THIS INCREASE WAS DUE TO A SOUTHWESTERLY 925MB WIND OF 40-55 KT FROM THE FORECAST AREA DOWN INTO TEXAS...HELPING TO BRING GULF OF MEXICO MOISTURE NORTHWARD. THE WINDS ARE ALSO HOLDING TEMPERATURES UP WITH READINGS MAINLY IN THE 40S. 925MB TEMPS WERE ANALYZED PER RAP AT 08Z OF 9-13C...NEARLY IDENTICAL TO 00Z RAOBS. TO THE WEST...A 988MB LOW WAS LOCATED JUST EAST OF ALLIANCE NEBRASKA. A NARROW BAND OF SHOWERS WERE TRYING TO DEVELOP OVER CENTRAL NEBRASKA EAST OF THIS LOW...ASSOCIATED WITH 310K ISENTROPIC LIFT. THIS PUTS THE SHOWERS ROOTED AROUND 600MB. HOWEVER...THE AFOREMENTIONED LOWER LEVEL DRY AIR HAS KEPT RAIN FROM REACHING THE GROUND. SYNOPTIC OVERVIEW...500MB HEIGHT PROGS FROM MODELS ARE NEARLY IDENTICAL NOW...BOTH IN TIMING AND STRENGTH...FOR THE TRACK OF THE VIGOROUS SHORTWAVE CURRENTLY IN NORTHEAST COLORADO. OVERALL TREND OVER THE PAST WEEK FROM MODELS WAS A SLOWER...DEEPER AND MORE NORTHWEST TRACK. CURRENT CONSENSUS TRACKS THE SHORTWAVE ACROSS WATERTOWN SD LATE THIS AFTERNOON...AND INTO THE DULUTH MN AREA BY 12Z TUE. THE ASSOCIATED SURFACE LOW CURRENTLY IN WESTERN NEBRASKA TAKES NEARLY THE SAME ROUTE...WITH THE PRESSURE WEAKENING TONIGHT AS THE LOW BEGINS TO OCCLUDE. PRECIPITATION...THE TRACK OF THE SURFACE/500MB FEATURES ARE GENERALLY NOT FAVORABLE FOR PRECIPITATION FOR THE FORECAST AREA...ESPECIALLY WITH ALL THE DRY AIR IN PLACE. IF THERE WAS MORE GULF OF MEXICO MOISTURE TO WORK WITH...SAY DEWPOINTS IN THE 50S...THIS MIGHT BE A DIFFERENT STORY. HOWEVER...MODELS STILL CONTINUE TO INDICATE 3 WAVES OF POTENTIAL PRECIPITATION... 1. THE FIRST IS ASSOCIATED WITH THE 310K ISENTROPIC LIFT IN CENTRAL NEBRASKA. THIS LIFT LOOKS TO TRACK NORTHEAST ACROSS THE AREA TODAY. THE PLENTIFUL LOW TO MID LEVEL DRY AIR IN PLACE MAY MAKE IT TOUGH FOR PRECIPITATION TO OCCUR. IN FACT...OVERALL MODEL TRENDS CONTINUE TO SUGGEST LESS AND LESS PRECIPITATION WITH THIS FIRST WAVE...WITH THE REGIONAL CANADIAN AND TO SOME DEGREE THE RAP EVEN SUGGESTING DRY. HAVE LOWERED CHANCES TO 20-30 WITH THIS WAVE. 2. THE SECOND WAVE OF POSSIBLE PRECIPITATION COMES DURING THE EVENING HOURS ASSOCIATED WITH THE LOWS COLD FRONT. THERES A GOOD MODEL CONSENSUS FOR A NARROW LINE OF SCT-BKN SHOWERS TO DEVELOP NEAR I-35 NEAR 00Z...CORRELATING WELL WITH AN AXIS OF WEAK TO MODERATE 0- 2KM MOISTURE CONVERGENCE AND THE LEFT EXIT REGION OF AN UPPER JET. 31.00Z NAM SOUNDINGS SHOW A BRIEF 1 HOUR PERIOD OF THE SHOWERS... WHERE ALSO CAPE ROOTED ABOVE 850MB CLIMBS TO 200-300 J/KG. THIS CAPE AND FORCING SHOULD BE ENOUGH TO GENERATE SOME ISOLATED THUNDER. GIVEN LIKELY INVERTED-V SOUNDING AND 850MB WINDS OF 45-50 KT...THE SHOWERS AND THUNDERSTORMS COULD PRODUCE STRONG TO POSSIBLY EVEN DAMAGING WIND GUSTS. AGAIN...THIS WILL BE ISOLATED. 3. THE FINAL WAVE OF PRECIPITATION IS THE COLD CONVEYOR BELT OF SNOW WRAPPING AROUND THE SYSTEM...POSSIBLY IMPACTING THE FORECAST AREA AFTER MIDNIGHT. MODELS CONTINUE TO TREND MORE AND MORE NORTHWEST WITH THE REACH OF THE COLD CONVEYOR. AS IT STANDS NOW...LOCATIONS MAINLY NORTHWEST OF A LINE FROM AUSTIN MN TO WAUSAU WI LOOK TO SEE THE SNOW. IN ADDITION...THE SNOW MAY NOT ARRIVE UNTIL AFTER 09Z. AS SUCH...ANY ACCUMULATIONS PRIOR TO 12Z WILL BE VERY LIGHT. TEMPERATURES...925MB READINGS ARE PROGGED TO MOSTLY HOLD IN THE 9- 13C RANGE THROUGHOUT THE DAY...WARMEST TOWARDS THE LATE AFTERNOON AT TIME OF PEAK MIXING. THE WARMER START TO THE DAY PLUS LIMITED IMPACT FROM PRECIPITATION WOULD SUPPORT A WARMER SCENARIO. IN ADDITION...IT APPEARS WE SHOULD HAVE SOME SUN BOTH EARLY IN THE DAY AND AGAIN LATER IN THE AFTERNOON. WITH A BREEZY SOUTH WIND AIDING IN ADVECTING WARMER AIR IN FROM THE SOUTH TOO...SEEMS LIKE A SITUATION TO LEAN TOWARDS THE WARMER SIDE OF GUIDANCE. DO THINK...THOUGH...THE MET SHOWING 70-71 FOR BLACK RIVER FALLS...WINONA AND BOSCOBEL IS A BIT TOO AMBITIOUS. READINGS WILL REALLY TAKE A TUMBLE TONIGHT AS COLD AIR WRAPS AROUND THE SURFACE LOW. BY 12Z TUE...925MB TEMPS ARE PROGGED BETWEEN -5 AND -7C. A 30 DEGREE TEMPERATURE DROP IS POSSIBLE BETWEEN 00Z AND 12Z. WINDS...925MB WINDS OF 30-40 KT HOLD NEARLY STEADY THROUGH MUCH OF THE DAY...BUT IT DOES APPEAR THESE SHOULD PICK UP TOWARDS 45 KT AS THE LOW AND FRONT NEAR. THE STRONGEST WINDS STILL LOOK TO OCCUR ALONG/SOUTH OF I-90. THE DAYTIME MIXING PLUS ISALLOBARIC HELP SHOULD PUSH WIND GUSTS TOWARDS THE 35-45 MPH RANGE. CANNOT RULE OUT SOME HIGHER GUSTS. THEN WE HAVE THE COLD FRONTAL PASSAGE TONIGHT WITH 925MB WINDS ALSO 30-40 KT AIDED TOO BY A PRESSURE RISE. MUCH OF THIS SHOULD EASILY MIX DOWN...RESULTING IN GUSTS OF 30-40 MPH WITH MAYBE SOME HIGHER ONES TOWARDS 45 MPH. AFTER COLLABORATION WITH MPX...DMX...DVN AND MKX...SETTLED ON A WIND ADVISORY FOR MOSTLY THE COUNTIES ALONG/WEST OF US-52. THIS ADVISORY MAY NEED EXPANSION TO THE EAST INTO FAR SOUTHWEST WI DURING THE DAY SHIFT. FOR NOW PUT THESE COUNTIES IN AN SPS. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 342 AM CDT MON MAR 31 2014 ACTIVE WEATHER CONTINUES AND WE REALLY NEED TO WATCH THURSDAY NIGHT AND FRIDAY CLOSELY. MODELS HAVE TRENDED A LITTLE FASTER IN EXITING THE VIGOROUS SHORTWAVE TROUGH AND SURFACE LOW TO THE NORTHEAST. AS SUCH...HAVE SPED UP THE EXITING OF THE COLD CONVEYOR BELT SNOW AND BRINGING IN CLEARING QUICKER. WITH A FASTER EXIT...IT APPEARS THOSE LOCATIONS THAT DO SEE SNOW WILL SEE VERY LITTLE. VERY WINDY CONDITIONS TO START OFF THE DAY...ESPECIALLY ACROSS SOUTHEAST MN WHERE A SECONDARY COLD FRONT PASSES...SHOULD SLOWLY DIMINISH THROUGH THE DAY. BETTER SHOT TO LIGHTEN UP THE WINDS COMES TUESDAY NIGHT AS A RIDGE OF HIGH PRESSURE BUILDS IN FOR LOCATIONS NORTH OF I-90. THE NEXT CONCERN ON THE HORIZON INVOLVES THE DEEP UPPER TROUGH OFF THE PACIFIC NORTHWEST COAST. SUBJECTIVELY...THAT TROUGH LOOKS A LOT MEANER THAN THE ONE COMING INTO THE PLAINS RIGHT NOW. MODELS ARE IN VERY GOOD AGREEMENT DIGGING THIS FEATURE INTO THE SOUTHWESTERN U.S. ON WEDNESDAY...CAUSING RIDGING AND A WARM ADVECTION PATTERN TO DEVELOP DOWNSTREAM FROM THE GULF COAST INTO THE LOWER GREAT LAKES. THE BIG PROBLEM HERE IS THAT THE WARM ADVECTION PATTERN MOSTLY OCCURS ALOFT...AS THE LOW LEVELS ARE DOMINATED BY AN EASTERLY FLOW COMING OUT OF COLD...CANADIAN HIGH PRESSURE OVER THE NORTHERN GREAT LAKES AND ONTARIO. THIS SETS THE STAGE FOR POSSIBLE MIXED PRECIPITATION. 31.00Z GFS/NAM/ECMWF ARE ALL INDICATING A LEAD WAVE OF WARM ADVECTION PRECIPITATION IMPACTING MAINLY LOCATIONS SOUTH OF I-90 WEDNESDAY NIGHT INTO THURSDAY MORNING. THERE ARE CONCERNS WITH A WARM LAYER ALOFT AND LOSS OF ICE IN THE CLOUDS TO IMPACT PRECIPITATION TYPE. IN ADDITION...EVAPORATIVE COOLING FROM THE EASTERLY FLOW OF DRY AIR COMBINING WITH THE PRECIPITATION MAY SEND TEMPERATURES AT OR BELOW FREEZING. AS A RESULT...FORECAST INCLUDES A VARIETY OF PRECIPITATION TYPES. ATTENTION THEN TURNS TO THE TROUGH WHICH THE GFS/GFS ENSEMBLE/UKMET AND CANADIAN ARE ALL TRENDING TOWARDS THE DEEP ECMWF SOLUTION. THIS TROUGH LIFTS UP INTO THE FORECAST AREA ON FRIDAY...BRINGING WITH IT A MUCH DEEPER PLUME OF GULF MOISTURE ALONG WITH A FAIRLY DEEP SURFACE LOW. THERE ARE INDICATIONS WE COULD SEE ACCUMULATING WET SNOW...PARTICULARLY OVER OUR NORTHWEST...TO MIXED PRECIPITATION AND EVEN HEAVY RAINFALL. THERE MAY EVEN BE SOME THUNDERSTORMS OVER FAR SOUTHWEST WI THURSDAY NIGHT...BUT THE PROBABILITY IS TOO LOW TO INCLUDE AT THIS TIME. NEEDLESS TO SAY...RAISED PRECIPITATION CHANCES INTO THE 60-70 RANGE FOR MOST LOCATIONS THURSDAY NIGHT AND FRIDAY. LOOKS LIKE THE SYSTEM WILL GRADUALLY EXIT THE AREA FRIDAY NIGHT WITH DRIER AND WARMER WEATHER TO FOLLOW FOR THE WEEKEND AS HIGH PRESSURE BUILDS IN. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 1140 PM CDT SUN MAR 30 2014 SEVERAL DETAILS TO DEPICT IN THIS SET OF FORECASTS. THE FIRST IS THE WINDS AND ASSOCIATED GUSTS FOR MONDAY. ONCE THE INVERSION BEGINS TO MIX OUT MONDAY MORNING...STRONG WIND SPEEDS WILL EXIST IN THE MIXED LAYER TO GET BROUGHT DOWN TO THE SURFACE. THE 31.00Z NAM BUFKIT SOUNDINGS SHOW THE POTENTIAL FOR GUSTS TO REACH INTO THE MID 30 KNOT RANGE AT KRST MONDAY AFTERNOON AND TO AROUND 30 KNOTS AT KLSE. THESE WINDS WILL DIMINISH SOME LATE IN THE AFTERNOON OR EARLY EVENING AHEAD OF THE APPROACHING COLD FRONT. THERE IS A CHANCE FOR SOME FAST MOVING ELEVATED SHOWERS TO DEVELOP MONDAY MORNING ON THE NOSE OF THE RETURNING LOW LEVEL MOISTURE FROM THE GULF. NOT EXPECTING THESE TO LAST VERY LONG BUT FEEL THE WINDS ARE MORE IMPORTANT FOR TIMING...SO WILL SHOW A LONGER WINDOW OF A SHOWER CHANCE THAN WILL LIKELY OCCUR. A SECOND CHANCE FOR SOME SHOWERS...MAYBE EVEN A THUNDERSTORM...WILL COME AS THE COLD FRONT MOVES THROUGH DURING THE EARLY EVENING. THE CAPE IS ONLY ABOUT 200 J/KG FOR AN HOUR OR TWO AND CONFIDENCE ON THIS ACTUALLY PRODUCING THUNDER IS NOT HIGH ENOUGH TO INCLUDE IN THE FORECAST AT THIS TIME. ONCE THE COLD FRONT COMES THROUGH...THE WINDS WILL SWITCH AROUND TO THE SOUTHWEST BEHIND IT AND REMAIN GUSTY. GOOD LOW LEVEL LAPSE RATES BEHIND THE FRONT WITH STRONG COLD AIR ADVECTION WILL MAINTAIN GUSTS TO AROUND 30 KNOTS. && .FIRE WEATHER... ISSUED AT 342 AM CDT MON MAR 31 2014 BREEZY SOUTHERLY WINDS COMBINED WITH TEMPERATURES CLIMBING INTO THE MID 60S THIS AFTERNOON POSES SOME CONCERN FOR FIRE WEATHER. DEWPOINTS ALSO SHOULD MIX A BIT THIS AFTERNOON...PARTICULARLY OVER CENTRAL AND FAR SOUTHWEST WI WHICH SAW THAT HAPPEN YESTERDAY. FUELS ALSO WERE ABLE TO DRY OUT SOME FROM YESTERDAY. HOWEVER...RELATIVE HUMIDITY VALUES ONLY DROP TO A MINIMUM OF 35 PERCENT...PRECLUDING THE NEED FOR ANY FIRE WEATHER HAZARDS. ANOTHER ITEM TO WATCH IS ISOLATED THUNDERSTORMS COMING ACROSS THE AREA THIS EVENING. GIVEN THAT DRY AIR EXISTS BELOW THE CLOUD BASES...THESE THUNDERSTORMS MAY NOT PRODUCE MUCH RAINFALL. THUS...CANNOT RULE OUT SOME DRY LIGHTNING STRIKES. THE STORMS SHOULD ALSO PRODUCE SOME STRONG WINDS...SO IF A FIRE WOULD GET STARTED...THE WIND COULD HELP IT SPREAD A LITTLE. && .HYDROLOGY... ISSUED AT 342 AM CDT MON MAR 31 2014 FLOOD WATCH REMAINS ON TRACK FOR TREMPEALEAU...JACKSON AND CLARK COUNTIES. BOTH THE BLACK AND TREMPEALEAU RIVERS ARE RESPONDING TO THE SNOWMELT THAT HAS OCCURRED YESTERDAY THROUGH NOW. CONTINUED RAPID SNOWMELT OVER THE NEXT 24 HOURS FROM TEMPERATURES PEAKING UP IN THE MID 50S TO LOW 60S WILL ALLOW THE RIVERS TO CONTINUE RISING. IT APPEARS LIKELY THAT FLOOD WARNINGS WILL BE ISSUED SOMETIME TODAY...PARTICULARLY ON THE BLACK SINCE THE TREMPEALEAU RIVER BASIN MAY BE EXHAUSTED OF SNOWMELT. SHOULD BE A CLOSE CALL ON THE TREMPEALEAU AT DODGE...THOUGH. LOOKING AHEAD TO LATER IN THE WEEK...CONCERN IS GROWING OF A POSSIBLE HEAVY RAINFALL EVENT OVER THE SOUTHEAST HALF OF THE AREA THURSDAY NIGHT AND FRIDAY. WE WILL HAVE TO WATCH THIS TIME PERIOD CLOSELY. LUCKILY THERE ISNT GOING TO BE ANY SNOWMELT OVER THAT AREA. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...FLOOD WATCH FROM LATE TONIGHT THROUGH THURSDAY MORNING FOR WIZ029-033-034. MN...WIND ADVISORY FROM 1 PM THIS AFTERNOON TO 10 AM CDT TUESDAY FOR MNZ086-087-094-095. IA...WIND ADVISORY FROM 1 PM THIS AFTERNOON TO 7 AM CDT TUESDAY FOR IAZ008>010-018-019-029. && $$ SHORT TERM...AJ LONG TERM...AJ AVIATION...04 FIRE WEATHER...AJ HYDROLOGY...AJ
AREA FORECAST DISCUSSION...UPDATED
NWS PEACHTREE CITY GA
1038 AM EDT MON MAR 31 2014 .UPDATE... ONLY CHANGE TO THE FORECAST WILL BE FOR LOWER DEWPOINTS AND RELATIVE HUMIDITIES. VERY DRY JUST OFF THE SURFACE...AND WITH MIXING DEWPOINTS SHOULD DROP SIGNIFICANTLY. MAV/MET APPEAR TOO HIGH IN DEWPOINTS AND THE LATEST RUC APPEARS TO HAVE A BETTER HANDLING AT THE MIXING. 17 && .SHORT TERM /TODAY THROUGH TUESDAY/... /ISSUED AT 350 AM EDT MON MAR 31 2014/ UPPER RIDGE WILL BUILD ACROSS THE SOUTHEAST TODAY. THE RIDGE WILL FLATTEN SOME ON TUESDAY AS THE WEAK TRAILING END OF A SHORT WAVE PASSES OVER THE OHIO VALLEY. SHORT WAVE HAS LIMITED MOISTURE..SO EXPECT NO RAIN WITH IT BUT MAYBE SOME CLOUDS. THERE WILL BE A WARMING TREND AS HEIGHTS RISE AND WINDS COME AROUND TO THE SOUTHWEST. MAV/MET TEMPERATURES ARE CLOSE AND HAVE NOT DEVIATED MUCH. FROST ADVISORY REMAINS IN EFFECT UNTIL 9 AM. 41 .LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/... /ISSUED AT 350 AM EDT MON MAR 31 2014/ HIGH PRESSURE WILL DOMINATE AT THE BEGINNING OF THE LONG TERM AHEAD OF THE NEXT SYSTEM THAT WILL APPROACH LATE WEEK. STILL DIFFERENCES BETWEEN THE GFS AND ECMWF WITH THIS LATE WEEK SYSTEM IN TERMS OF BOTH THE POSITIONING OF FEATURES AND TIMING. ECMWF IS A LITTLE FURTHER NORTH WITH THE SFC LOW AND QUICKER WITH PUSHING THE FRONT THROUGH. BOTH MODELS BRING THE PRECIP IN ON FRIDAY BUT THE ECMWF PUSHES THE FRONT THROUGH BY SATURDAY MORNING. THE GFS ON THE OTHER HAND DOESNT PUSH THE FRONT THROUGH UNTIL LATER ON SATURDAY AND THUS THE GFS APPEARS TO INDICATE A FRIDAY AFTERNOON TO SATURDAY EVENT IN TERMS OF THE MORE ACTIVE WEATHER. FORECAST TRENDS TOWARDS THE SLOWER GFS SOLUTION. GFS SHOWS THE HIGHEST INSTABILITY FRIDAY EVENING WITH 2000 J/KG OF MUCAPE ACROSS NW GA. IN ADDITION IT PEGS AROUND 30 KTS OF LOW LEVEL SHEAR ACROSS N GA. ALTHOUGH THE SHEAR WITH THE SYSTEM DECREASES...INSTABILITY IS ENOUGH FOR STRONG TO SEVERE STORM POTENTIAL FRIDAY THROUGH SATURDAY SO THIS SYSTEM CONTINUES TO NEED TO BE MONITORED. 11 && .FIRE WEATHER... /ISSUED AT 350 AM EDT MON MAR 31 2014/ FUELS HAVE DRIED AND RELATIVE HUMIDITY VALUES DIP TO 25 PERCENT OR LESS FOR AROUND 4 HOURS MOST AREAS THIS AFTERNOON. WINDS SHOULD BE LIGHT SOUTHWEST. HAVE ISSUED A FIRE DANGER STATEMENT FOR THE ENTIRE CWA...ALTHOUGH A FEW AREAS MAY BE BORDERLINE FOR HUMIDITY. 41 && .AVIATION... 12Z UPDATE... VFR CONDITIONS EXPECTED THROUGH THE FORECAST PERIOD. LIGHT AND VARIABLE WINDS BECOMING NORTHWEST 5 TO 10KT THIS MORNING THEN BECOMING LIGHT SOUTHWEST BY AFTERNOON. //ATL CONFIDENCE...12Z UPDATE... HIGH ON ALL ELEMENTS. 41 && .PRELIMINARY POINT TEMPS/POPS... ATHENS 76 46 81 52 / 0 0 0 0 ATLANTA 74 52 78 56 / 0 0 0 0 BLAIRSVILLE 73 42 74 47 / 0 0 0 0 CARTERSVILLE 75 43 78 49 / 0 0 0 0 COLUMBUS 75 47 79 54 / 0 0 0 0 GAINESVILLE 73 49 76 54 / 0 0 0 0 MACON 75 41 80 49 / 0 0 0 0 ROME 75 43 78 48 / 0 0 0 0 PEACHTREE CITY 75 40 78 47 / 0 0 0 0 VIDALIA 77 49 82 55 / 0 0 0 0 && .FFC WATCHES/WARNINGS/ADVISORIES... FROST ADVISORY UNTIL 9 AM EDT THIS MORNING FOR THE FOLLOWING ZONES: BARTOW...BUTTS...CARROLL...CATOOSA...CHATTOOGA... CHEROKEE...CLAYTON...COBB...COWETA...DADE...DAWSON...DOUGLAS... FANNIN...FAYETTE...FLOYD...FORSYTH...GILMER...GORDON...HALL... HARALSON...HEARD...HENRY...JASPER...JONES...LAMAR...LUMPKIN... MERIWETHER...MONROE...MURRAY...NORTH FULTON...PAULDING... PICKENS...PIKE...POLK...SOUTH FULTON...SPALDING...TOWNS... TROUP...UNION...UPSON...WALKER...WHITE...WHITFIELD. && $$ SHORT TERM...41 LONG TERM....11 AVIATION...41
AREA FORECAST DISCUSSION
NWS GOODLAND KS
850 AM MDT MON MAR 31 2014 .UPDATE... ISSUED AT 846 AM MDT MON MAR 31 2014 HAVE RECEIVED MULTIPLE REPORTS OF NEAR ZERO VISIBILITY FROM RAWLINS...RED WILLOW...SHERIDAN AND DECATUR COUNTIES THIS MORNING. LOOKING AT SATELLITE IMAGERY THERE IS NOTICEABLE STREAKS OF DUST EVIDENT OVER THESE COUNTIES. EXPECT THE LOW VISIBILITIES TO PROGRESS EAST INTO NORTON AND GRAHAM COUNTIES THIS MORNING SO CHOSE TO INCLUDE THEM IN THE DUST STORM WARNING AS WELL. ALSO INCLUDED HITCHCOCK COUNTY BASED ON SATELLITE IMAGERY OF DUST STEAKS. WOULD EXPECT THE DUST TO DIMINISH DURING THE AFTERNOON AS THE STRONGER WINDS MOVE FURTHER EAST. THE WORST VISIBILITIES WILL BE SOUTH OF TILLED FIELDS AND DIRT ROADS. UPDATE ISSUED AT 811 AM MDT MON MAR 31 2014 EXPANDED HIGH WIND WARNING TO INCLUDE NORTON AND GRAHAM COUNTIES SINCE NORTON IS CURRENTLY REPORTING WIND GUSTS OF 53 KNOTS. UPDATE ISSUED AT 737 AM MDT MON MAR 31 2014 HAVE HAD AT ATLEAST A COUPLE REPORTS OF WIND GUSTS AROUND 60 MPH THIS MORNING...ONE AT WRAY ABOUT 90 MINUTES AGO AND ANOTHER AT ATWOOD ABOUT 11 MINUTES AGO. HAVE ALSO HAD 2 REPORTS JUST UNDER WARNING CRITERIA...ONE AT YUMA AND ANOTHER AT MCCOOK. THESE REPORTS DO MAKE SINCE GIVEN THE POSITION OF THE 500MB TROUGH WHICH HAS ITS BASE OVER THE NORTHERN HALF OF THE AREA THIS MORNING WHICH IS WHERE THE STRONGEST SUBSIDENCE WILL BE. LOCATIONS SOUTH OF I-70 SHOULD REMAIN BELOW WARNING CRITERIA SINCE THE BASE OF THE 500MB TROUGH WILL NOT MOVE THAT FAR SOUTH. ALSO EXCLUDED NORTON AND GRAHAM COUNTIES SINCE THE 500MB TROUGH LIFTS NORTHEAST BEFORE IT GETS TO THOSE TWO COUNTIES. EXPECT WINDS TO DECLINE DURING THE EARLY AFTERNOON AS THE STRONGER WINDS MOVE EAST OF THE AREA. WILL MORE THAN LIKELY DOWNGRADE THE CURRENT WARNING TO AN ADVISORY BY THEN...BUT FOR SIMPLICITY KEPT THE DURATION OF THE WARNING THE SAME AS THE ADVISORY. UPDATE ISSUED AT 510 AM MDT MON MAR 31 2014 HAVE ADJUSTED THE START TIME OF THE WIND ADVISORY 2 HOURS SOONER (BASICALLY NOW) GIVEN WIND GUSTS OF 60 MPH 1W YUMA AND 49 MPH IN WRAY AT THE AWOS. AM CONCERNED ABOUT REACHING HIGH WIND WARNING CRITERIA ACROSS THE NORTH CENTRAL AND NORTHWEST PORTIONS OF THE AREA GENERALLY NORTH OF THE INTERSTATE. RUC 800MB WINDS INCREASE THIS MORNING WITH 50-60KTS THROUGH 17Z OR SO ON THE BACKSIDE OF DEPARTING UPPER SYSTEM. HOWEVER...THIS AREA ALSO UNDER MORE CLOUDINESS WHICH COULD LIMIT FULL MIXING BUT ON THE OTHER HAND RADAR RETURNS SUGGEST SOME LIGHT SHOWERS OR VIRGA SO THE STRONGER WINDS MAY COME FROM THAT. WILL WATCH CLOSELY FOR THE NEXT HOUR AND SEE WHAT HAPPENS AT WRAY AWOS (K2V5). && .SHORT TERM...(TODAY THROUGH WEDNESDAY NIGHT) ISSUED AT 300 AM MDT MON MAR 31 2014 TODAY-TONIGHT...UPPER DISTURBANCE THAT HAS BEEN ADVERTISED THE PAST FEW DAYS IS CURRENTLY OVER NORTHEAST COLORADO. A SURFACE LOW IS DEEPENING OVER NORTH CENTRAL NEBRASKA. WEST TO SOUTHWEST WINDS ARE BREEZY TO WINDY AT TIMES. FOR THE REST OF TODAY AND INTO TONIGHT THE UPPER LOW AND ASSOCIATED SFC LOW WILL LIFT NORTHEAST REACHING EASTERN SOUTH DAKOTA BY THE END OF THE DAY CONTINUING TOWARD THE GREAT LAKES TONIGHT. WEATHER CONCERNS DURING THIS PERIOD ARE WINDS AND THREAT OF BLOWING DUST. BLENDED MAV/MET/LAMP WINDS ALONG WITH OUTPUT FROM LOCAL WIND PROGRAM. THIS IS PRODUCING WIND GUSTS GENERALLY IN THE 36KT TO 46KT RANGE...HIGHEST ALONG AND NORTH OF THE INTERSTATE. FOR NOW WIND ADVISORY LOOKS GOOD BUT WILL NEED TO WATCH AS WE ARE CLOSE TO WARNING CRITERIA (50KTS) GENERALLY ALONG AND NORTH OF THE KS/NE BORDER. THESE WINDS WILL LIKELY CAUSE AREAS OF BLOWING DUST AND CURRENT FORECAST HAS THIS ALREADY ADVERTISED. HIGH TEMPERATURES IN THE 50S TO LOW 60S...WARMEST ACROSS THE EAST AND SOUTHERLY PARTS OF THE AREA. LOWS IN THE MID 20S TO AROUND 30. AM CONCERNED A BIT THAT MID AND HIGH CLOUDS MAY KEEP TEMPS A BIT WARMER DESPITE SFC HIGH NOSING INTO THE AREA. TUESDAY-TUESDAY NIGHT...SFC HIGH SLOWLY MOVES EAST WITH LOW PRESSURE DEVELOPING ALONG THE FRONT RANGE. THIS WILL CREATE AN INCREASING PRESSURE GRADIENT ACROSS THE AREA WITH SOUTH/SOUTHEAST WINDS GUSTING 35 TO PERHAPS 40 MPH...MAINLY WEST OF A LINE FROM BENKELMAN TO COLBY AND LEOTI WITH STRONGEST WINDS NEAR THE CO/KS BORDER. WINDS BECOME EAST/NORTHEAST 10-15 MPH TUESDAY NIGHT. A NARROW SLIVER OF INSTABILITY DEVELOPS ALONG THE CO/KS BORDER TUESDAY AFTERNOON WITH AN INCREASE IN MAINLY MID LEVEL CLOUDINESS. FEEL THAT THIS COMBINED WITH SOME LOW LEVEL WIND CONVERGENCE WILL BE ENOUGH TO AT LEAST WARRANT ISOLATED THUNDERSTORMS MAINLY IN YUMA COUNTY. HIGH TEMPERATURES IN THE LOW TO MID 50S EAST...UPPER 50S WITH LOW 60S ACROSS THE WEST. LOWS IN THE UPPER 20S WEST TO MID 30S EAST. WEDNESDAY-WEDNESDAY NIGHT...FOCUS NOW TURNS TO UPPER TROUGH WHICH BY THE END OF THE DAY WEDNESDAY SHOULD BE ACROSS THE INTERMOUNTAIN WEST WITH A SLOW EASTWARD PROGRESSION WEDNESDAY NIGHT. AT THE SFC EAST/NORTHEAST WINDS WILL SLOWLY INCREASE THROUGH DAY THEN SHIFT TO THE NORTH/NORTHEAST DURING THE NIGHT AS LOW PRESSURE OVER SOUTHEAST COLORADO SLIDES SOUTH INTO THE TEXAS PANHANDLE. HIGH TEMPERATURES GENERALLY IN THE 50S WITH PERHAPS A 60 DEGREE READING ACROSS THE FAR SOUTH AND SOUTHWEST. LOWS GENERALLY IN THE LOW TO MID 30S. PRECIPITATION CHANCES INCREASE A BIT LATE WEDNESDAY AFTERNOON AND CONTINUE TO INCREASE WEDNESDAY NIGHT WITH MOST LIKELY PRECIPITATION TYPE BEING RAIN THROUGH MIDNIGHT THEN A TRANSITION TO SNOW FOR THE NORTHWEST HALF OF THE AREA. ANY ACCUMULATION LOOKS TO BE UNDER AN INCH AT PRESENT TIME. .LONG TERM...(THURDAY THROUGH SUNDAY) ISSUED AT 300 AM MDT MON MAR 31 2014 THURSDAY-THURSDAY NIGHT...ECMWF/GFS/GEFS ARE ACTUALLY IN BETTER AGREEMENT ON TROUGH PASSAGE THU...WHILE GEM IS STILL SLOWER/STRONGER/FURTHER NORTH. FINER DETAILS BETWEEN MODELS CONTINUE TO DIFFERENCES...HOWEVER OVERALL TREND SEEMS TO FAVOR THE NORTHERN PART OF OUR CWA FOR DEVELOPMENT OF A BAND OF PRECIP AND COOLER TEMPS. I BUMPED POPS UP (50 PERCENT NORTH) AND LOWERED HIGHS (40-45F). BASED ON THE AMOUNT OF CAA...AND POSSIBLE CLOUDS/PRECIP THIS MAY STILL BE TOO WARM. PRECIP TYPE WILL BE TRICKY AS TEMP PROFILES WOULD GENERALLY INDICATE SATURATION TO WET BULB TEMP WOULD SUPPORT AT LEAST A MIX OR COMPLETE SNOW CHANGEOVER THROUGH MOST OF THE DAY. I TIED RAIN/SNOW MIX TO HOURLY TEMPS FOR SIMPLICITY SAKE...BUT WE WILL PROBABLY NEED TO FINE TUNE THIS AS WE GET A BETTER HANDLE ON DAYTIME TEMPS AND AXIS OF PRECIP. THIS CHANGE OVER ALSO IMPACTS SNOW AMOUNTS...WITH ALL SNOW POSSIBLY PUTTING US WITHIN ADVISORY CRITERIA NORTH OF I-70 (3-5"). CURRENT FORECAST IS CONSIDERABLY LESS SINCE IT IS FAVORING MORE OF A MIX/LIQUID EVENT...JUST ANOTHER THING WE WILL NEED TO FINE TUNE. FRIDAY-SUNDAY...SHORTWAVE RIDGING WILL BE FOLLOWED BY A TRANSITION TO SPLIT FLOW...SHIFTING THE NORTHERN STORM TRACK WELL NORTH AND EAST. THIS WILL SUPPORT DRY CONDITIONS FRI/FRI NIGHT. WE SHOULD ALSO SEE A RETURN OF SEASONAL TO ABOVE NORMAL TEMPS BY NEXT WEEKEND. THE MAIN DIFFERENCE BETWEEN MODELS IS ON SATURDAY-SUNDAY WHEN ECMWF SHOWS A STRONGER TROUGH DEVELOPING ALONG THE SOUTHERN STORM TRACK AND MOVES THIS TROUGH FURTHER NORTH TOWARDS KS. GFS IS WEAKER AND FAVORS SUNDAY FOR PRECIP CHANCES. I KEPT SLIGHT CHANCE POPS IN PLACE DURING THESE PERIODS...HOWEVER CONFIDENCE IS NOT PARTICULARLY HIGH CONSIDERING THE LACK OF CONSISTENCY AND RANGE. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING) ISSUED AT 300 AM MDT MON MAR 31 2014 KGLD AND KMCK...VFR CONDITIONS EXPECTED THROUGH THE PERIOD. MAY HAVE MVFR/IFR CIGS IN BLOWING DUST LATE THIS MORNING THROUGH MUCH OF THE AFTERNOON BUT ITS TOO EARLY RIGHT NOW TO PINPOINT THE MOST LIKELY TIME FOR IT TO IMPACT TERMINALS. OTHERWISE...WEST WINDS 20 TO 25KTS WITH HIGHER GUSTS AT TAF ISSUANCE WILL VEER TO THE NORTHWEST BY 15Z WITH AROUND 30KT SUSTAINED WINDS GUSTING 40-45KTS THROUGH 20Z OR SO BEFORE VERY SLOW DECREASING FROM 21Z TO 00Z TUESDAY. FOR TONIGHT SFC HIGH MOVES IN WITH NORTH TO NORTHEAST WINDS UNDER 10KTS THROUGH 06Z BECOMING NORTHEAST UNDER 5KTS AT KMCK...SOUTHEAST AROUND 6KTS AT KGLD BY 12Z. SHOULD SEE AN INCREASE IN CLOUDINESS LATE THIS MORNING BUT ESPECIALLY AFTER DARK AND THROUGH THE REST OF THE TAF PERIOD. && .FIRE WEATHER... ISSUED AT 300 AM MDT MON MAR 31 2014 TODAY...WILL NEED TO MONITOR LOCATIONS ALONG AND SOUTH OF HIGHWAY 40 AND ESPECIALLY SOUTH OF HIGHWAY 96 FOR RELATIVE HUMIDITY VALUES APPROACHING 15 PERCENT. RIGHT NOW AM JUST ABOVE THAT THRESHOLD NEEDED FOR FIRE WEATHER HIGHLITE. WINDS IN THIS AREA GENERALLY FROM THE NORTHWEST GUSTING 40 TO PERHAPS 45 MPH. TUESDAY...WILL NEED TO WATCH FAR WEST/SOUTHWEST PORTIONS OF CHEYENNE AND KIT CARSON COUNTIES (GENERALLY WEST OF A LINE FROM FLAGLER TO KIT CARSON) FOR THE POSSIBILITY OF CRITICAL FIRE WEATHER CONDITIONS BEING MET. CURRENTLY HAVE RELATIVE HUMIDITY VALUES DOWN TO 16-17%. THESE LOW VALUES WILL COMBINE WITH SOUTH TO SOUTHEAST WINDS GUSTING 35 TO PERHAPS 40 MPH. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...HIGH WIND WARNING UNTIL 7 PM MDT /8 PM CDT/ THIS EVENING FOR KSZ001-013-014. DUST STORM WARNING UNTIL 8 PM CDT THIS EVENING FOR KSZ002>004- 015-016. WIND ADVISORY UNTIL 7 PM MDT /8 PM CDT/ THIS EVENING FOR KSZ027>029-041-042. CO...HIGH WIND WARNING UNTIL 7 PM MDT THIS EVENING FOR COZ090-091. WIND ADVISORY UNTIL 7 PM MDT THIS EVENING FOR COZ092. NE...HIGH WIND WARNING UNTIL 7 PM MDT THIS EVENING FOR NEZ079. DUST STORM WARNING UNTIL 8 PM CDT THIS EVENING FOR NEZ080-081. && $$ UPDATE...JTL SHORT TERM...99 LONG TERM...DR AVIATION...99 FIRE WEATHER...99
AREA FORECAST DISCUSSION
NWS GOODLAND KS
812 AM MDT MON MAR 31 2014 .UPDATE... ISSUED AT 811 AM MDT MON MAR 31 2014 EXPANDED HIGH WIND WARNING TO INCLUDE NORTON AND GRAHAM COUNTIES SINCE NORTON IS CURRENTLY REPORTING WIND GUSTS OF 53 KNOTS. UPDATE ISSUED AT 737 AM MDT MON MAR 31 2014 HAVE HAD AT ATLEAST A COUPLE REPORTS OF WIND GUSTS AROUND 60 MPH THIS MORNING...ONE AT WRAY ABOUT 90 MINUTES AGO AND ANOTHER AT ATWOOD ABOUT 11 MINUTES AGO. HAVE ALSO HAD 2 REPORTS JUST UNDER WARNING CRITERIA...ONE AT YUMA AND ANOTHER AT MCCOOK. THESE REPORTS DO MAKE SINCE GIVEN THE POSITION OF THE 500MB TROUGH WHICH HAS ITS BASE OVER THE NORTHERN HALF OF THE AREA THIS MORNING WHICH IS WHERE THE STRONGEST SUBSIDENCE WILL BE. LOCATIONS SOUTH OF I-70 SHOULD REMAIN BELOW WARNING CRITERIA SINCE THE BASE OF THE 500MB TROUGH WILL NOT MOVE THAT FAR SOUTH. ALSO EXCLUDED NORTON AND GRAHAM COUNTIES SINCE THE 500MB TROUGH LIFTS NORTHEAST BEFORE IT GETS TO THOSE TWO COUNTIES. EXPECT WINDS TO DECLINE DURING THE EARLY AFTERNOON AS THE STRONGER WINDS MOVE EAST OF THE AREA. WILL MORE THAN LIKELY DOWNGRADE THE CURRENT WARNING TO AN ADVISORY BY THEN...BUT FOR SIMPLICITY KEPT THE DURATION OF THE WARNING THE SAME AS THE ADVISORY. UPDATE ISSUED AT 510 AM MDT MON MAR 31 2014 HAVE ADJUSTED THE START TIME OF THE WIND ADVISORY 2 HOURS SOONER (BASICALLY NOW) GIVEN WIND GUSTS OF 60 MPH 1W YUMA AND 49 MPH IN WRAY AT THE AWOS. AM CONCERNED ABOUT REACHING HIGH WIND WARNING CRITERIA ACROSS THE NORTH CENTRAL AND NORTHWEST PORTIONS OF THE AREA GENERALLY NORTH OF THE INTERSTATE. RUC 800MB WINDS INCREASE THIS MORNING WITH 50-60KTS THROUGH 17Z OR SO ON THE BACKSIDE OF DEPARTING UPPER SYSTEM. HOWEVER...THIS AREA ALSO UNDER MORE CLOUDINESS WHICH COULD LIMIT FULL MIXING BUT ON THE OTHER HAND RADAR RETURNS SUGGEST SOME LIGHT SHOWERS OR VIRGA SO THE STRONGER WINDS MAY COME FROM THAT. WILL WATCH CLOSELY FOR THE NEXT HOUR AND SEE WHAT HAPPENS AT WRAY AWOS (K2V5). && .SHORT TERM...(TODAY THROUGH WEDNESDAY NIGHT) ISSUED AT 300 AM MDT MON MAR 31 2014 TODAY-TONIGHT...UPPER DISTURBANCE THAT HAS BEEN ADVERTISED THE PAST FEW DAYS IS CURRENTLY OVER NORTHEAST COLORADO. A SURFACE LOW IS DEEPENING OVER NORTH CENTRAL NEBRASKA. WEST TO SOUTHWEST WINDS ARE BREEZY TO WINDY AT TIMES. FOR THE REST OF TODAY AND INTO TONIGHT THE UPPER LOW AND ASSOCIATED SFC LOW WILL LIFT NORTHEAST REACHING EASTERN SOUTH DAKOTA BY THE END OF THE DAY CONTINUING TOWARD THE GREAT LAKES TONIGHT. WEATHER CONCERNS DURING THIS PERIOD ARE WINDS AND THREAT OF BLOWING DUST. BLENDED MAV/MET/LAMP WINDS ALONG WITH OUTPUT FROM LOCAL WIND PROGRAM. THIS IS PRODUCING WIND GUSTS GENERALLY IN THE 36KT TO 46KT RANGE...HIGHEST ALONG AND NORTH OF THE INTERSTATE. FOR NOW WIND ADVISORY LOOKS GOOD BUT WILL NEED TO WATCH AS WE ARE CLOSE TO WARNING CRITERIA (50KTS) GENERALLY ALONG AND NORTH OF THE KS/NE BORDER. THESE WINDS WILL LIKELY CAUSE AREAS OF BLOWING DUST AND CURRENT FORECAST HAS THIS ALREADY ADVERTISED. HIGH TEMPERATURES IN THE 50S TO LOW 60S...WARMEST ACROSS THE EAST AND SOUTHERLY PARTS OF THE AREA. LOWS IN THE MID 20S TO AROUND 30. AM CONCERNED A BIT THAT MID AND HIGH CLOUDS MAY KEEP TEMPS A BIT WARMER DESPITE SFC HIGH NOSING INTO THE AREA. TUESDAY-TUESDAY NIGHT...SFC HIGH SLOWLY MOVES EAST WITH LOW PRESSURE DEVELOPING ALONG THE FRONT RANGE. THIS WILL CREATE AN INCREASING PRESSURE GRADIENT ACROSS THE AREA WITH SOUTH/SOUTHEAST WINDS GUSTING 35 TO PERHAPS 40 MPH...MAINLY WEST OF A LINE FROM BENKELMAN TO COLBY AND LEOTI WITH STRONGEST WINDS NEAR THE CO/KS BORDER. WINDS BECOME EAST/NORTHEAST 10-15 MPH TUESDAY NIGHT. A NARROW SLIVER OF INSTABILITY DEVELOPS ALONG THE CO/KS BORDER TUESDAY AFTERNOON WITH AN INCREASE IN MAINLY MID LEVEL CLOUDINESS. FEEL THAT THIS COMBINED WITH SOME LOW LEVEL WIND CONVERGENCE WILL BE ENOUGH TO AT LEAST WARRANT ISOLATED THUNDERSTORMS MAINLY IN YUMA COUNTY. HIGH TEMPERATURES IN THE LOW TO MID 50S EAST...UPPER 50S WITH LOW 60S ACROSS THE WEST. LOWS IN THE UPPER 20S WEST TO MID 30S EAST. WEDNESDAY-WEDNESDAY NIGHT...FOCUS NOW TURNS TO UPPER TROUGH WHICH BY THE END OF THE DAY WEDNESDAY SHOULD BE ACROSS THE INTERMOUNTAIN WEST WITH A SLOW EASTWARD PROGRESSION WEDNESDAY NIGHT. AT THE SFC EAST/NORTHEAST WINDS WILL SLOWLY INCREASE THROUGH DAY THEN SHIFT TO THE NORTH/NORTHEAST DURING THE NIGHT AS LOW PRESSURE OVER SOUTHEAST COLORADO SLIDES SOUTH INTO THE TEXAS PANHANDLE. HIGH TEMPERATURES GENERALLY IN THE 50S WITH PERHAPS A 60 DEGREE READING ACROSS THE FAR SOUTH AND SOUTHWEST. LOWS GENERALLY IN THE LOW TO MID 30S. PRECIPITATION CHANCES INCREASE A BIT LATE WEDNESDAY AFTERNOON AND CONTINUE TO INCREASE WEDNESDAY NIGHT WITH MOST LIKELY PRECIPITATION TYPE BEING RAIN THROUGH MIDNIGHT THEN A TRANSITION TO SNOW FOR THE NORTHWEST HALF OF THE AREA. ANY ACCUMULATION LOOKS TO BE UNDER AN INCH AT PRESENT TIME. .LONG TERM...(THURDAY THROUGH SUNDAY) ISSUED AT 300 AM MDT MON MAR 31 2014 THURSDAY-THURSDAY NIGHT...ECMWF/GFS/GEFS ARE ACTUALLY IN BETTER AGREEMENT ON TROUGH PASSAGE THU...WHILE GEM IS STILL SLOWER/STRONGER/FURTHER NORTH. FINER DETAILS BETWEEN MODELS CONTINUE TO DIFFERENCES...HOWEVER OVERALL TREND SEEMS TO FAVOR THE NORTHERN PART OF OUR CWA FOR DEVELOPMENT OF A BAND OF PRECIP AND COOLER TEMPS. I BUMPED POPS UP (50 PERCENT NORTH) AND LOWERED HIGHS (40-45F). BASED ON THE AMOUNT OF CAA...AND POSSIBLE CLOUDS/PRECIP THIS MAY STILL BE TOO WARM. PRECIP TYPE WILL BE TRICKY AS TEMP PROFILES WOULD GENERALLY INDICATE SATURATION TO WET BULB TEMP WOULD SUPPORT AT LEAST A MIX OR COMPLETE SNOW CHANGEOVER THROUGH MOST OF THE DAY. I TIED RAIN/SNOW MIX TO HOURLY TEMPS FOR SIMPLICITY SAKE...BUT WE WILL PROBABLY NEED TO FINE TUNE THIS AS WE GET A BETTER HANDLE ON DAYTIME TEMPS AND AXIS OF PRECIP. THIS CHANGE OVER ALSO IMPACTS SNOW AMOUNTS...WITH ALL SNOW POSSIBLY PUTTING US WITHIN ADVISORY CRITERIA NORTH OF I-70 (3-5"). CURRENT FORECAST IS CONSIDERABLY LESS SINCE IT IS FAVORING MORE OF A MIX/LIQUID EVENT...JUST ANOTHER THING WE WILL NEED TO FINE TUNE. FRIDAY-SUNDAY...SHORTWAVE RIDGING WILL BE FOLLOWED BY A TRANSITION TO SPLIT FLOW...SHIFTING THE NORTHERN STORM TRACK WELL NORTH AND EAST. THIS WILL SUPPORT DRY CONDITIONS FRI/FRI NIGHT. WE SHOULD ALSO SEE A RETURN OF SEASONAL TO ABOVE NORMAL TEMPS BY NEXT WEEKEND. THE MAIN DIFFERENCE BETWEEN MODELS IS ON SATURDAY-SUNDAY WHEN ECMWF SHOWS A STRONGER TROUGH DEVELOPING ALONG THE SOUTHERN STORM TRACK AND MOVES THIS TROUGH FURTHER NORTH TOWARDS KS. GFS IS WEAKER AND FAVORS SUNDAY FOR PRECIP CHANCES. I KEPT SLIGHT CHANCE POPS IN PLACE DURING THESE PERIODS...HOWEVER CONFIDENCE IS NOT PARTICULARLY HIGH CONSIDERING THE LACK OF CONSISTENCY AND RANGE. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING) ISSUED AT 300 AM MDT MON MAR 31 2014 KGLD AND KMCK...VFR CONDITIONS EXPECTED THROUGH THE PERIOD. MAY HAVE MVFR/IFR CIGS IN BLOWING DUST LATE THIS MORNING THROUGH MUCH OF THE AFTERNOON BUT ITS TOO EARLY RIGHT NOW TO PINPOINT THE MOST LIKELY TIME FOR IT TO IMPACT TERMINALS. OTHERWISE...WEST WINDS 20 TO 25KTS WITH HIGHER GUSTS AT TAF ISSUANCE WILL VEER TO THE NORTHWEST BY 15Z WITH AROUND 30KT SUSTAINED WINDS GUSTING 40-45KTS THROUGH 20Z OR SO BEFORE VERY SLOW DECREASING FROM 21Z TO 00Z TUESDAY. FOR TONIGHT SFC HIGH MOVES IN WITH NORTH TO NORTHEAST WINDS UNDER 10KTS THROUGH 06Z BECOMING NORTHEAST UNDER 5KTS AT KMCK...SOUTHEAST AROUND 6KTS AT KGLD BY 12Z. SHOULD SEE AN INCREASE IN CLOUDINESS LATE THIS MORNING BUT ESPECIALLY AFTER DARK AND THROUGH THE REST OF THE TAF PERIOD. && .FIRE WEATHER... ISSUED AT 300 AM MDT MON MAR 31 2014 TODAY...WILL NEED TO MONITOR LOCATIONS ALONG AND SOUTH OF HIGHWAY 40 AND ESPECIALLY SOUTH OF HIGHWAY 96 FOR RELATIVE HUMIDITY VALUES APPROACHING 15 PERCENT. RIGHT NOW AM JUST ABOVE THAT THRESHOLD NEEDED FOR FIRE WEATHER HIGHLITE. WINDS IN THIS AREA GENERALLY FROM THE NORTHWEST GUSTING 40 TO PERHAPS 45 MPH. TUESDAY...WILL NEED TO WATCH FAR WEST/SOUTHWEST PORTIONS OF CHEYENNE AND KIT CARSON COUNTIES (GENERALLY WEST OF A LINE FROM FLAGLER TO KIT CARSON) FOR THE POSSIBILITY OF CRITICAL FIRE WEATHER CONDITIONS BEING MET. CURRENTLY HAVE RELATIVE HUMIDITY VALUES DOWN TO 16-17%. THESE LOW VALUES WILL COMBINE WITH SOUTH TO SOUTHEAST WINDS GUSTING 35 TO PERHAPS 40 MPH. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...HIGH WIND WARNING UNTIL 7 PM MDT /8 PM CDT/ THIS EVENING FOR KSZ001>004-013>016. WIND ADVISORY UNTIL 7 PM MDT /8 PM CDT/ THIS EVENING FOR KSZ027>029-041-042. CO...HIGH WIND WARNING UNTIL 7 PM MDT THIS EVENING FOR COZ090-091. WIND ADVISORY UNTIL 7 PM MDT THIS EVENING FOR COZ092. NE...HIGH WIND WARNING UNTIL 7 PM MDT /8 PM CDT/ THIS EVENING FOR NEZ079>081. && $$ UPDATE...JTL SHORT TERM...99 LONG TERM...DR AVIATION...99 FIRE WEATHER...99
AREA FORECAST DISCUSSION
NWS GOODLAND KS
744 AM MDT MON MAR 31 2014 .UPDATE... ISSUED AT 737 AM MDT MON MAR 31 2014 HAVE HAD AT ATLEAST A COUPLE REPORTS OF WIND GUSTS AROUND 60 MPH THIS MORNING...ONE AT WRAY ABOUT 90 MINUTES AGO AND ANOTHER AT ATWOOD ABOUT 11 MINUTES AGO. HAVE ALSO HAD 2 REPORTS JUST UNDER WARNING CRITERIA...ONE AT YUMA AND ANOTHER AT MCCOOK. THESE REPORTS DO MAKE SINCE GIVEN THE POSITION OF THE 500MB TROUGH WHICH HAS ITS BASE OVER THE NORTHERN HALF OF THE AREA THIS MORNING WHICH IS WHERE THE STRONGEST SUBSIDENCE WILL BE. LOCATIONS SOUTH OF I-70 SHOULD REMAIN BELOW WARNING CRITERIA SINCE THE BASE OF THE 500MB TROUGH WILL NOT MOVE THAT FAR SOUTH. ALSO EXCLUDED NORTON AND GRAHAM COUNTIES SINCE THE 500MB TROUGH LIFTS NORTHEAST BEFORE IT GETS TO THOSE TWO COUNTIES. EXPECT WINDS TO DECLINE DURING THE EARLY AFTERNOON AS THE STRONGER WINDS MOVE EAST OF THE AREA. WILL MORE THAN LIKELY DOWNGRADE THE CURRENT WARNING TO AN ADVISORY BY THEN...BUT FOR SIMPLICITY KEPT THE DURATION OF THE WARNING THE SAME AS THE ADVISORY. UPDATE ISSUED AT 510 AM MDT MON MAR 31 2014 HAVE ADJUSTED THE START TIME OF THE WIND ADVISORY 2 HOURS SOONER (BASICALLY NOW) GIVEN WIND GUSTS OF 60 MPH 1W YUMA AND 49 MPH IN WRAY AT THE AWOS. AM CONCERNED ABOUT REACHING HIGH WIND WARNING CRITERIA ACROSS THE NORTH CENTRAL AND NORTHWEST PORTIONS OF THE AREA GENERALLY NORTH OF THE INTERSTATE. RUC 800MB WINDS INCREASE THIS MORNING WITH 50-60KTS THROUGH 17Z OR SO ON THE BACKSIDE OF DEPARTING UPPER SYSTEM. HOWEVER...THIS AREA ALSO UNDER MORE CLOUDINESS WHICH COULD LIMIT FULL MIXING BUT ON THE OTHER HAND RADAR RETURNS SUGGEST SOME LIGHT SHOWERS OR VIRGA SO THE STRONGER WINDS MAY COME FROM THAT. WILL WATCH CLOSELY FOR THE NEXT HOUR AND SEE WHAT HAPPENS AT WRAY AWOS (K2V5). && .SHORT TERM...(TODAY THROUGH WEDNESDAY NIGHT) ISSUED AT 300 AM MDT MON MAR 31 2014 TODAY-TONIGHT...UPPER DISTURBANCE THAT HAS BEEN ADVERTISED THE PAST FEW DAYS IS CURRENTLY OVER NORTHEAST COLORADO. A SURFACE LOW IS DEEPENING OVER NORTH CENTRAL NEBRASKA. WEST TO SOUTHWEST WINDS ARE BREEZY TO WINDY AT TIMES. FOR THE REST OF TODAY AND INTO TONIGHT THE UPPER LOW AND ASSOCIATED SFC LOW WILL LIFT NORTHEAST REACHING EASTERN SOUTH DAKOTA BY THE END OF THE DAY CONTINUING TOWARD THE GREAT LAKES TONIGHT. WEATHER CONCERNS DURING THIS PERIOD ARE WINDS AND THREAT OF BLOWING DUST. BLENDED MAV/MET/LAMP WINDS ALONG WITH OUTPUT FROM LOCAL WIND PROGRAM. THIS IS PRODUCING WIND GUSTS GENERALLY IN THE 36KT TO 46KT RANGE...HIGHEST ALONG AND NORTH OF THE INTERSTATE. FOR NOW WIND ADVISORY LOOKS GOOD BUT WILL NEED TO WATCH AS WE ARE CLOSE TO WARNING CRITERIA (50KTS) GENERALLY ALONG AND NORTH OF THE KS/NE BORDER. THESE WINDS WILL LIKELY CAUSE AREAS OF BLOWING DUST AND CURRENT FORECAST HAS THIS ALREADY ADVERTISED. HIGH TEMPERATURES IN THE 50S TO LOW 60S...WARMEST ACROSS THE EAST AND SOUTHERLY PARTS OF THE AREA. LOWS IN THE MID 20S TO AROUND 30. AM CONCERNED A BIT THAT MID AND HIGH CLOUDS MAY KEEP TEMPS A BIT WARMER DESPITE SFC HIGH NOSING INTO THE AREA. TUESDAY-TUESDAY NIGHT...SFC HIGH SLOWLY MOVES EAST WITH LOW PRESSURE DEVELOPING ALONG THE FRONT RANGE. THIS WILL CREATE AN INCREASING PRESSURE GRADIENT ACROSS THE AREA WITH SOUTH/SOUTHEAST WINDS GUSTING 35 TO PERHAPS 40 MPH...MAINLY WEST OF A LINE FROM BENKELMAN TO COLBY AND LEOTI WITH STRONGEST WINDS NEAR THE CO/KS BORDER. WINDS BECOME EAST/NORTHEAST 10-15 MPH TUESDAY NIGHT. A NARROW SLIVER OF INSTABILITY DEVELOPS ALONG THE CO/KS BORDER TUESDAY AFTERNOON WITH AN INCREASE IN MAINLY MID LEVEL CLOUDINESS. FEEL THAT THIS COMBINED WITH SOME LOW LEVEL WIND CONVERGENCE WILL BE ENOUGH TO AT LEAST WARRANT ISOLATED THUNDERSTORMS MAINLY IN YUMA COUNTY. HIGH TEMPERATURES IN THE LOW TO MID 50S EAST...UPPER 50S WITH LOW 60S ACROSS THE WEST. LOWS IN THE UPPER 20S WEST TO MID 30S EAST. WEDNESDAY-WEDNESDAY NIGHT...FOCUS NOW TURNS TO UPPER TROUGH WHICH BY THE END OF THE DAY WEDNESDAY SHOULD BE ACROSS THE INTERMOUNTAIN WEST WITH A SLOW EASTWARD PROGRESSION WEDNESDAY NIGHT. AT THE SFC EAST/NORTHEAST WINDS WILL SLOWLY INCREASE THROUGH DAY THEN SHIFT TO THE NORTH/NORTHEAST DURING THE NIGHT AS LOW PRESSURE OVER SOUTHEAST COLORADO SLIDES SOUTH INTO THE TEXAS PANHANDLE. HIGH TEMPERATURES GENERALLY IN THE 50S WITH PERHAPS A 60 DEGREE READING ACROSS THE FAR SOUTH AND SOUTHWEST. LOWS GENERALLY IN THE LOW TO MID 30S. PRECIPITATION CHANCES INCREASE A BIT LATE WEDNESDAY AFTERNOON AND CONTINUE TO INCREASE WEDNESDAY NIGHT WITH MOST LIKELY PRECIPITATION TYPE BEING RAIN THROUGH MIDNIGHT THEN A TRANSITION TO SNOW FOR THE NORTHWEST HALF OF THE AREA. ANY ACCUMULATION LOOKS TO BE UNDER AN INCH AT PRESENT TIME. .LONG TERM...(THURDAY THROUGH SUNDAY) ISSUED AT 300 AM MDT MON MAR 31 2014 THURSDAY-THURSDAY NIGHT...ECMWF/GFS/GEFS ARE ACTUALLY IN BETTER AGREEMENT ON TROUGH PASSAGE THU...WHILE GEM IS STILL SLOWER/STRONGER/FURTHER NORTH. FINER DETAILS BETWEEN MODELS CONTINUE TO DIFFERENCES...HOWEVER OVERALL TREND SEEMS TO FAVOR THE NORTHERN PART OF OUR CWA FOR DEVELOPMENT OF A BAND OF PRECIP AND COOLER TEMPS. I BUMPED POPS UP (50 PERCENT NORTH) AND LOWERED HIGHS (40-45F). BASED ON THE AMOUNT OF CAA...AND POSSIBLE CLOUDS/PRECIP THIS MAY STILL BE TOO WARM. PRECIP TYPE WILL BE TRICKY AS TEMP PROFILES WOULD GENERALLY INDICATE SATURATION TO WET BULB TEMP WOULD SUPPORT AT LEAST A MIX OR COMPLETE SNOW CHANGEOVER THROUGH MOST OF THE DAY. I TIED RAIN/SNOW MIX TO HOURLY TEMPS FOR SIMPLICITY SAKE...BUT WE WILL PROBABLY NEED TO FINE TUNE THIS AS WE GET A BETTER HANDLE ON DAYTIME TEMPS AND AXIS OF PRECIP. THIS CHANGE OVER ALSO IMPACTS SNOW AMOUNTS...WITH ALL SNOW POSSIBLY PUTTING US WITHIN ADVISORY CRITERIA NORTH OF I-70 (3-5"). CURRENT FORECAST IS CONSIDERABLY LESS SINCE IT IS FAVORING MORE OF A MIX/LIQUID EVENT...JUST ANOTHER THING WE WILL NEED TO FINE TUNE. FRIDAY-SUNDAY...SHORTWAVE RIDGING WILL BE FOLLOWED BY A TRANSITION TO SPLIT FLOW...SHIFTING THE NORTHERN STORM TRACK WELL NORTH AND EAST. THIS WILL SUPPORT DRY CONDITIONS FRI/FRI NIGHT. WE SHOULD ALSO SEE A RETURN OF SEASONAL TO ABOVE NORMAL TEMPS BY NEXT WEEKEND. THE MAIN DIFFERENCE BETWEEN MODELS IS ON SATURDAY-SUNDAY WHEN ECMWF SHOWS A STRONGER TROUGH DEVELOPING ALONG THE SOUTHERN STORM TRACK AND MOVES THIS TROUGH FURTHER NORTH TOWARDS KS. GFS IS WEAKER AND FAVORS SUNDAY FOR PRECIP CHANCES. I KEPT SLIGHT CHANCE POPS IN PLACE DURING THESE PERIODS...HOWEVER CONFIDENCE IS NOT PARTICULARLY HIGH CONSIDERING THE LACK OF CONSISTENCY AND RANGE. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING) ISSUED AT 300 AM MDT MON MAR 31 2014 KGLD AND KMCK...VFR CONDITIONS EXPECTED THROUGH THE PERIOD. MAY HAVE MVFR/IFR CIGS IN BLOWING DUST LATE THIS MORNING THROUGH MUCH OF THE AFTERNOON BUT ITS TOO EARLY RIGHT NOW TO PINPOINT THE MOST LIKELY TIME FOR IT TO IMPACT TERMINALS. OTHERWISE...WEST WINDS 20 TO 25KTS WITH HIGHER GUSTS AT TAF ISSUANCE WILL VEER TO THE NORTHWEST BY 15Z WITH AROUND 30KT SUSTAINED WINDS GUSTING 40-45KTS THROUGH 20Z OR SO BEFORE VERY SLOW DECREASING FROM 21Z TO 00Z TUESDAY. FOR TONIGHT SFC HIGH MOVES IN WITH NORTH TO NORTHEAST WINDS UNDER 10KTS THROUGH 06Z BECOMING NORTHEAST UNDER 5KTS AT KMCK...SOUTHEAST AROUND 6KTS AT KGLD BY 12Z. SHOULD SEE AN INCREASE IN CLOUDINESS LATE THIS MORNING BUT ESPECIALLY AFTER DARK AND THROUGH THE REST OF THE TAF PERIOD. && .FIRE WEATHER... ISSUED AT 300 AM MDT MON MAR 31 2014 TODAY...WILL NEED TO MONITOR LOCATIONS ALONG AND SOUTH OF HIGHWAY 40 AND ESPECIALLY SOUTH OF HIGHWAY 96 FOR RELATIVE HUMIDITY VALUES APPROACHING 15 PERCENT. RIGHT NOW AM JUST ABOVE THAT THRESHOLD NEEDED FOR FIRE WEATHER HIGHLITE. WINDS IN THIS AREA GENERALLY FROM THE NORTHWEST GUSTING 40 TO PERHAPS 45 MPH. TUESDAY...WILL NEED TO WATCH FAR WEST/SOUTHWEST PORTIONS OF CHEYENNE AND KIT CARSON COUNTIES (GENERALLY WEST OF A LINE FROM FLAGLER TO KIT CARSON) FOR THE POSSIBILITY OF CRITICAL FIRE WEATHER CONDITIONS BEING MET. CURRENTLY HAVE RELATIVE HUMIDITY VALUES DOWN TO 16-17%. THESE LOW VALUES WILL COMBINE WITH SOUTH TO SOUTHEAST WINDS GUSTING 35 TO PERHAPS 40 MPH. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...HIGH WIND WARNING UNTIL 7 PM MDT /8 PM CDT/ THIS EVENING FOR KSZ001>003-013>015. WIND ADVISORY UNTIL 7 PM MDT /8 PM CDT/ THIS EVENING FOR KSZ004- 016-027>029-041-042. CO...HIGH WIND WARNING UNTIL 7 PM MDT THIS EVENING FOR COZ090-091. WIND ADVISORY UNTIL 7 PM MDT THIS EVENING FOR COZ092. NE...HIGH WIND WARNING UNTIL 7 PM MDT /8 PM CDT/ THIS EVENING FOR NEZ079>081. && $$ UPDATE...JTL SHORT TERM...99 LONG TERM...DR AVIATION...99 FIRE WEATHER...99
AREA FORECAST DISCUSSION
NWS GOODLAND KS
515 AM MDT MON MAR 31 2014 .UPDATE... ISSUED AT 510 AM MDT MON MAR 31 2014 HAVE ADJUSTED THE START TIME OF THE WIND ADVISORY 2 HOURS SOONER (BASICALLY NOW) GIVEN WIND GUSTS OF 60 MPH 1W YUMA AND 49 MPH IN WRAY AT THE AWOS. AM CONCERNED ABOUT REACHING HIGH WIND WARNING CRITERIA ACROSS THE NORTH CENTRAL AND NORTHWEST PORTIONS OF THE AREA GENERALLY NORTH OF THE INTERSTATE. RUC 800MB WINDS INCREASE THIS MORNING WITH 50-60KTS THROUGH 17Z OR SO ON THE BACKSIDE OF DEPARTING UPPER SYSTEM. HOWEVER...THIS AREA ALSO UNDER MORE CLOUDINESS WHICH COULD LIMIT FULL MIXING BUT ON THE OTHER HAND RADAR RETURNS SUGGEST SOME LIGHT SHOWERS OR VIRGA SO THE STRONGER WINDS MAY COME FROM THAT. WILL WATCH CLOSELY FOR THE NEXT HOUR AND SEE WHAT HAPPENS AT WRAY AWOS (K2V5). && .SHORT TERM...(TODAY THROUGH WEDNESDAY NIGHT) ISSUED AT 300 AM MDT MON MAR 31 2014 TODAY-TONIGHT...UPPER DISTURBANCE THAT HAS BEEN ADVERTISED THE PAST FEW DAYS IS CURRENTLY OVER NORTHEAST COLORADO. A SURFACE LOW IS DEEPENING OVER NORTH CENTRAL NEBRASKA. WEST TO SOUTHWEST WINDS ARE BREEZY TO WINDY AT TIMES. FOR THE REST OF TODAY AND INTO TONIGHT THE UPPER LOW AND ASSOCIATED SFC LOW WILL LIFT NORTHEAST REACHING EASTERN SOUTH DAKOTA BY THE END OF THE DAY CONTINUING TOWARD THE GREAT LAKES TONIGHT. WEATHER CONCERNS DURING THIS PERIOD ARE WINDS AND THREAT OF BLOWING DUST. BLENDED MAV/MET/LAMP WINDS ALONG WITH OUTPUT FROM LOCAL WIND PROGRAM. THIS IS PRODUCING WIND GUSTS GENERALLY IN THE 36KT TO 46KT RANGE...HIGHEST ALONG AND NORTH OF THE INTERSTATE. FOR NOW WIND ADVISORY LOOKS GOOD BUT WILL NEED TO WATCH AS WE ARE CLOSE TO WARNING CRITERIA (50KTS) GENERALLY ALONG AND NORTH OF THE KS/NE BORDER. THESE WINDS WILL LIKELY CAUSE AREAS OF BLOWING DUST AND CURRENT FORECAST HAS THIS ALREADY ADVERTISED. HIGH TEMPERATURES IN THE 50S TO LOW 60S...WARMEST ACROSS THE EAST AND SOUTHERLY PARTS OF THE AREA. LOWS IN THE MID 20S TO AROUND 30. AM CONCERNED A BIT THAT MID AND HIGH CLOUDS MAY KEEP TEMPS A BIT WARMER DESPITE SFC HIGH NOSING INTO THE AREA. TUESDAY-TUESDAY NIGHT...SFC HIGH SLOWLY MOVES EAST WITH LOW PRESSURE DEVELOPING ALONG THE FRONT RANGE. THIS WILL CREATE AN INCREASING PRESSURE GRADIENT ACROSS THE AREA WITH SOUTH/SOUTHEAST WINDS GUSTING 35 TO PERHAPS 40 MPH...MAINLY WEST OF A LINE FROM BENKELMAN TO COLBY AND LEOTI WITH STRONGEST WINDS NEAR THE CO/KS BORDER. WINDS BECOME EAST/NORTHEAST 10-15 MPH TUESDAY NIGHT. A NARROW SLIVER OF INSTABILITY DEVELOPS ALONG THE CO/KS BORDER TUESDAY AFTERNOON WITH AN INCREASE IN MAINLY MID LEVEL CLOUDINESS. FEEL THAT THIS COMBINED WITH SOME LOW LEVEL WIND CONVERGENCE WILL BE ENOUGH TO AT LEAST WARRANT ISOLATED THUNDERSTORMS MAINLY IN YUMA COUNTY. HIGH TEMPERATURES IN THE LOW TO MID 50S EAST...UPPER 50S WITH LOW 60S ACROSS THE WEST. LOWS IN THE UPPER 20S WEST TO MID 30S EAST. WEDNESDAY-WEDNESDAY NIGHT...FOCUS NOW TURNS TO UPPER TROUGH WHICH BY THE END OF THE DAY WEDNESDAY SHOULD BE ACROSS THE INTERMOUNTAIN WEST WITH A SLOW EASTWARD PROGRESSION WEDNESDAY NIGHT. AT THE SFC EAST/NORTHEAST WINDS WILL SLOWLY INCREASE THROUGH DAY THEN SHIFT TO THE NORTH/NORTHEAST DURING THE NIGHT AS LOW PRESSURE OVER SOUTHEAST COLORADO SLIDES SOUTH INTO THE TEXAS PANHANDLE. HIGH TEMPERATURES GENERALLY IN THE 50S WITH PERHAPS A 60 DEGREE READING ACROSS THE FAR SOUTH AND SOUTHWEST. LOWS GENERALLY IN THE LOW TO MID 30S. PRECIPITATION CHANCES INCREASE A BIT LATE WEDNESDAY AFTERNOON AND CONTINUE TO INCREASE WEDNESDAY NIGHT WITH MOST LIKELY PRECIPITATION TYPE BEING RAIN THROUGH MIDNIGHT THEN A TRANSITION TO SNOW FOR THE NORTHWEST HALF OF THE AREA. ANY ACCUMULATION LOOKS TO BE UNDER AN INCH AT PRESENT TIME. .LONG TERM...(THURDAY THROUGH SUNDAY) ISSUED AT 300 AM MDT MON MAR 31 2014 THURSDAY-THURSDAY NIGHT...ECMWF/GFS/GEFS ARE ACTUALLY IN BETTER AGREEMENT ON TROUGH PASSAGE THU...WHILE GEM IS STILL SLOWER/STRONGER/FURTHER NORTH. FINER DETAILS BETWEEN MODELS CONTINUE TO DIFFERENCES...HOWEVER OVERALL TREND SEEMS TO FAVOR THE NORTHERN PART OF OUR CWA FOR DEVELOPMENT OF A BAND OF PRECIP AND COOLER TEMPS. I BUMPED POPS UP (50 PERCENT NORTH) AND LOWERED HIGHS (40-45F). BASED ON THE AMOUNT OF CAA...AND POSSIBLE CLOUDS/PRECIP THIS MAY STILL BE TOO WARM. PRECIP TYPE WILL BE TRICKY AS TEMP PROFILES WOULD GENERALLY INDICATE SATURATION TO WET BULB TEMP WOULD SUPPORT AT LEAST A MIX OR COMPLETE SNOW CHANGEOVER THROUGH MOST OF THE DAY. I TIED RAIN/SNOW MIX TO HOURLY TEMPS FOR SIMPLICITY SAKE...BUT WE WILL PROBABLY NEED TO FINE TUNE THIS AS WE GET A BETTER HANDLE ON DAYTIME TEMPS AND AXIS OF PRECIP. THIS CHANGE OVER ALSO IMPACTS SNOW AMOUNTS...WITH ALL SNOW POSSIBLY PUTTING US WITHIN ADVISORY CRITERIA NORTH OF I-70 (3-5"). CURRENT FORECAST IS CONSIDERABLY LESS SINCE IT IS FAVORING MORE OF A MIX/LIQUID EVENT...JUST ANOTHER THING WE WILL NEED TO FINE TUNE. FRIDAY-SUNDAY...SHORTWAVE RIDGING WILL BE FOLLOWED BY A TRANSITION TO SPLIT FLOW...SHIFTING THE NORTHERN STORM TRACK WELL NORTH AND EAST. THIS WILL SUPPORT DRY CONDITIONS FRI/FRI NIGHT. WE SHOULD ALSO SEE A RETURN OF SEASONAL TO ABOVE NORMAL TEMPS BY NEXT WEEKEND. THE MAIN DIFFERENCE BETWEEN MODELS IS ON SATURDAY-SUNDAY WHEN ECMWF SHOWS A STRONGER TROUGH DEVELOPING ALONG THE SOUTHERN STORM TRACK AND MOVES THIS TROUGH FURTHER NORTH TOWARDS KS. GFS IS WEAKER AND FAVORS SUNDAY FOR PRECIP CHANCES. I KEPT SLIGHT CHANCE POPS IN PLACE DURING THESE PERIODS...HOWEVER CONFIDENCE IS NOT PARTICULARLY HIGH CONSIDERING THE LACK OF CONSISTENCY AND RANGE. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING) ISSUED AT 300 AM MDT MON MAR 31 2014 KGLD AND KMCK...VFR CONDITIONS EXPECTED THROUGH THE PERIOD. MAY HAVE MVFR/IFR CIGS IN BLOWING DUST LATE THIS MORNING THROUGH MUCH OF THE AFTERNOON BUT ITS TOO EARLY RIGHT NOW TO PINPOINT THE MOST LIKELY TIME FOR IT TO IMPACT TERMINALS. OTHERWISE...WEST WINDS 20 TO 25KTS WITH HIGHER GUSTS AT TAF ISSUANCE WILL VEER TO THE NORTHWEST BY 15Z WITH AROUND 30KT SUSTAINED WINDS GUSTING 40-45KTS THROUGH 20Z OR SO BEFORE VERY SLOW DECREASING FROM 21Z TO 00Z TUESDAY. FOR TONIGHT SFC HIGH MOVES IN WITH NORTH TO NORTHEAST WINDS UNDER 10KTS THROUGH 06Z BECOMING NORTHEAST UNDER 5KTS AT KMCK...SOUTHEAST AROUND 6KTS AT KGLD BY 12Z. SHOULD SEE AN INCREASE IN CLOUDINESS LATE THIS MORNING BUT ESPECIALLY AFTER DARK AND THROUGH THE REST OF THE TAF PERIOD. && .FIRE WEATHER... ISSUED AT 300 AM MDT MON MAR 31 2014 TODAY...WILL NEED TO MONITOR LOCATIONS ALONG AND SOUTH OF HIGHWAY 40 AND ESPECIALLY SOUTH OF HIGHWAY 96 FOR RELATIVE HUMIDITY VALUES APPROACHING 15 PERCENT. RIGHT NOW AM JUST ABOVE THAT THRESHOLD NEEDED FOR FIRE WEATHER HIGHLITE. WINDS IN THIS AREA GENERALLY FROM THE NORTHWEST GUSTING 40 TO PERHAPS 45 MPH. TUESDAY...WILL NEED TO WATCH FAR WEST/SOUTHWEST PORTIONS OF CHEYENNE AND KIT CARSON COUNTIES (GENERALLY WEST OF A LINE FROM FLAGLER TO KIT CARSON) FOR THE POSSIBILITY OF CRITICAL FIRE WEATHER CONDITIONS BEING MET. CURRENTLY HAVE RELATIVE HUMIDITY VALUES DOWN TO 16-17%. THESE LOW VALUES WILL COMBINE WITH SOUTH TO SOUTHEAST WINDS GUSTING 35 TO PERHAPS 40 MPH. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...WIND ADVISORY UNTIL 7 PM MDT /8 PM CDT/ THIS EVENING FOR KSZ001>004-013>016-027>029-041-042. CO...WIND ADVISORY UNTIL 7 PM MDT THIS EVENING FOR COZ090>092. NE...WIND ADVISORY UNTIL 7 PM MDT /8 PM CDT/ THIS EVENING FOR NEZ079>081. && $$ UPDATE...99 SHORT TERM...99 LONG TERM...DR AVIATION...99 FIRE WEATHER...99
AREA FORECAST DISCUSSION
NWS GRAY ME
1008 AM EDT MON MAR 31 2014 .SYNOPSIS... LOW PRESSURE WILL MEANDER OFFSHORE TODAY...BEFORE FINALLY PULLING AWAY TONIGHT. HIGH PRESSURE WILL NUDGE IN BEHIND THE LOW FOR TUESDAY. A WEAK FRONT WILL CROSS THE AREA ON WEDNESDAY. HIGH PRESSURE WILL KEEP THINGS DRY THROUGH FRIDAY. LOW PRESSURE WILL TRACK INTO ONTARIO AND QUEBEC NEXT WEEKEND...SPREADING PRECIPITATION ACROSS MAINE AND NEW HAMPSHIRE. && .NEAR TERM /TODAY/... 10AM UPDATE... BAND OF PRECIPITATION HAS WEAKENED A BIT AND SHIFTED SLIGHTLY EASTWARD. HAVE REMOVED THE WINTER WEATHER ADVISORIES FOR AREAS BEHIND THE BAND. ADDITIONAL LIGHT ICE AND SLEET ACCUMULATIONS ARE POSSIBLE IN THE REMAINING ADVISORY AREA. WILL CONTINUE TO SEE A TRANSITION FROM FREEZING RAIN TO SLEET THEN TO SNOW BEFORE PRECIPITATION ENDS AROUND NOON. 830AM UPDATE... NARROW BAND OF PRIMARILY SLEET / FREEZING RAIN / RAIN CONTINUES TO PERSIST OVER ROUGHLY THE SAME AREA JUST INLAND OF THE COAST THIS MORNING. SOME SNOW WAS NOTED ON THE NORTHERN END OF THE BAND AT WISCASSET AND AUGUSTA. TEMPERATURE PROFILE ALOFT NOTED ON THE GYX SOUNDING THIS MORNING SHOWS A WELL PRONOUNCED SLEET SOUNDING WITH A LARGE INVERSION TO +6 C AT AROUND 800 MB WITH A STEEP COOLING TO AROUND -6 C AT 900 MB. AS THE DAY GOES ON... EXPECT THE WARMER AIR ALOFT TO SHIFT EAST... SO THE PRECIPITATION WILL CHANGE TO SLEET AND SNOW WITH LESS FREEZING RAIN. SURFACE TEMPERATURES WILL BE NEAR OR JUST ABOVE FREEZING SO THE TOTAL ACCUMULATION WILL LIKELY REMAIN NEAR OR BELOW ONE INCH. 7AM UPDATE... HAVE UPDATE THE GRIDS TO HIT THE FREEZING RAIN AND SLEET HARD ACROSS SOUTHERN INTERIOR PORTIONS OF THE FORECAST AREA AS DRIVING CONTINUES TO BECOME MORE AND MORE TREACHEROUS. ICE ACCRETION WILL BE A QUARTER TO NEARLY A HALF INCH IN THIS REGION. HAVE ALSO UPDATED TO REMOVE WINTER WEATHER ADVISORIES AND FLOOD WATCHES IN AREAS WHERE THE PRECIPITATION HAS COME TO AN END. ORIGINAL DISCUSSION... BANDS OF RAIN AND MIXED PRECIPITATION CONTINUE TO ROTATE BACK INTO THE FORECAST AREA FROM THE GULF OF MAINE EARLY THIS MORNING. THIS WILL ALLOW FOR UP TO A QUICK INCH OF ADDITIONAL RAINFALL ON TOP OF THE HEAVY RAINS THAT FELL OVER SOUTHERN LOCATIONS YESTERDAY. LATEST HRRR RUN DEPICTS THIS PRECIPITATION ASSOCIATED WITH THE UPPER LEVEL TROUGH VERY WELL. MUCH OF THE RAINFALL/MIX WILL BE DISSIPATING AROUND 16Z. AREAS OF SLEET AND FREEZING RAIN CONTINUE OVER CENTRAL LOCATIONS...HOWEVER IT HAS BEEN LIGHT. FOR NOW...WILL CONTINUE WITH THE WINTER WEATHER ADVISORIES THIS PACKAGE. WITH PLENTY OF CLOUD COVER AND STRONG...GUSTY NORTHERLY WINDS...WE DO NOT EXPECT THE TEMPERATURES TO RECOVER SIGNIFICANTLY TODAY. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/... STUBBORN SURFACE AND UPPER LEVEL LOW SLOWLY MOVE OUT TO SEA TONIGHT...ALLOWING FOR CLEARING TO FINALLY TAKE PLACE. SUNSHINE WILL MAKE AN APPEARANCE BACK TO OUR FORECAST AREA ON TUESDAY...WITH MODERATING TEMPERATURES AND MUCH LESS IN THE WAY OF GUSTY WINDS. && .LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/... MODELS ARE IN GENERAL AGREEMENT ON BROAD WESTERLY OR WEST- SOUTHWEST FLOW THIS PERIOD...THAT KEEPS ARCTIC AIR BOTTLED UP WELL TO OUR NORTH AND RESULTS IN NEAR NORMAL TEMPERATURES FOR THE PERIOD. DIFFERENCES EMERGE AFTER THURSDAY WITH TIMING OF INDIVIDUAL SHORTWAVES ADDING UNCERTAINTY TO THE FORECAST. IN THE DAILIES...A COLD FRONT WILL CROSS THE AREA WEDNESDAY FOLLOWED BY HIGH PRESSURE AND DRY AIR FOR THURSDAY AND FRIDAY. LOW PRESSURE APPROACHES FROM THE GREAT LAKES FOR SATURDAY AND SUNDAY. && .AVIATION /14Z MONDAY THROUGH FRIDAY/... SHORT TERM...ONE LAST ROUND OF LOCALLY IFR CONDITIONS AND RAIN/SNOW/SLEET WILL CONTINUE INTO THIS MORNING WITH IMPROVING CONDITIONS LATER IN THE DAY. WINDS WILL BE GUSTY OUT OF THE NORTH. LONG TERM... WED...SCT MVFR IN RAIN OR SNOW SHOWERS. SAT - SUN...AREAS OF MVFR IN RAIN AND SNOW WITH LOCAL IFR POSSIBLE. && .MARINE... SHORT TERM...NORTHERLY GALES EXPECTED RIGHT THROUGH TONIGHT AS LOW PRESSURE IS SLOW TO PULL AWAY. LONG TERM... THU...SMALL CRAFT WINDS AND SEAS ARE LIKELY. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...WINTER WEATHER ADVISORY UNTIL NOON EDT TODAY FOR MEZ018-019- 022>028. NH...WINTER WEATHER ADVISORY UNTIL NOON EDT TODAY FOR NHZ008>010- 013-014. MARINE...SMALL CRAFT ADVISORY UNTIL NOON EDT TUESDAY FOR ANZ151-153. GALE WARNING UNTIL NOON EDT TUESDAY FOR ANZ150-152-154. && $$ NEAR TERM UPDATE... KIMBLE
AREA FORECAST DISCUSSION
NWS GRAY ME
834 AM EDT MON MAR 31 2014 .SYNOPSIS... LOW PRESSURE WILL MEANDER OFFSHORE TODAY...BEFORE FINALLY PULLING AWAY TONIGHT. HIGH PRESSURE WILL NUDGE IN BEHIND THE LOW FOR TUESDAY. A WEAK FRONT WILL CROSS THE AREA ON WEDNESDAY. HIGH PRESSURE WILL KEEP THINGS DRY THROUGH FRIDAY. LOW PRESSURE WILL TRACK INTO ONTARIO AND QUEBEC NEXT WEEKEND...SPREADING PRECIPITATION ACROSS MAINE AND NEW HAMPSHIRE. && .NEAR TERM /TODAY/... 830AM UPDATE... NARROW BAND OF PRIMARILY SLEET / FREEZING RAIN / RAIN CONTINUES TO PERSIST OVER ROUGHLY THE SAME AREA JUST INLAND OF THE COAST THIS MORNING. SOME SNOW WAS NOTED ON THE NORTHERN END OF THE BAND AT WISCASSET AND AUGUSTA. TEMPERATURE PROFILE ALOFT NOTED ON THE GYX SOUNDING THIS MORNING SHOWS A WELL PRONOUNCED SLEET SOUNDING WITH A LARGE INVERSION TO +6 C AT AROUND 800 MB WITH A STEEP COOLING TO AROUND -6 C AT 900 MB. AS THE DAY GOES ON... EXPECT THE WARMER AIR ALOFT TO SHIFT EAST... SO THE PRECIPITATION WILL CHANGE TO SLEET AND SNOW WITH LESS FREEZING RAIN. SURFACE TEMPERATURES WILL BE NEAR OR JUST ABOVE FREEZING SO THE TOTAL ACCUMULATION WILL LIKELY REMAIN NEAR OR BELOW ONE INCH. 7AM UPDATE... HAVE UPDATE THE GRIDS TO HIT THE FREEZING RAIN AND SLEET HARD ACROSS SOUTHERN INTERIOR PORTIONS OF THE FORECAST AREA AS DRIVING CONTINUES TO BECOME MORE AND MORE TREACHEROUS. ICE ACCRETION WILL BE A QUARTER TO NEARLY A HALF INCH IN THIS REGION. HAVE ALSO UPDATED TO REMOVE WINTER WEATHER ADVISORIES AND FLOOD WATCHES IN AREAS WHERE THE PRECIPITATION HAS COME TO AN END. ORIGINAL DISCUSSION... BANDS OF RAIN AND MIXED PRECIPITATION CONTINUE TO ROTATE BACK INTO THE FORECAST AREA FROM THE GULF OF MAINE EARLY THIS MORNING. THIS WILL ALLOW FOR UP TO A QUICK INCH OF ADDITIONAL RAINFALL ON TOP OF THE HEAVY RAINS THAT FELL OVER SOUTHERN LOCATIONS YESTERDAY. LATEST HRRR RUN DEPICTS THIS PRECIPITATION ASSOCIATED WITH THE UPPER LEVEL TROUGH VERY WELL. MUCH OF THE RAINFALL/MIX WILL BE DISSIPATING AROUND 16Z. AREAS OF SLEET AND FREEZING RAIN CONTINUE OVER CENTRAL LOCATIONS...HOWEVER IT HAS BEEN LIGHT. FOR NOW...WILL CONTINUE WITH THE WINTER WEATHER ADVISORIES THIS PACKAGE. WITH PLENTY OF CLOUD COVER AND STRONG...GUSTY NORTHERLY WINDS...WE DO NOT EXPECT THE TEMPERATURES TO RECOVER SIGNIFICANTLY TODAY. && .SHORT TERM /TONIGHT AND TUESDAY/... STUBBORN SURFACE AND UPPER LEVEL LOW SLOWLY MOVE OUT TO SEA TONIGHT...ALLOWING FOR CLEARING TO FINALLY TAKE PLACE. SUNSHINE WILL MAKE AN APPEARANCE BACK TO OUR FORECAST AREA ON TUESDAY...WITH MODERATING TEMPERATURES AND MUCH LESS IN THE WAY OF GUSTY WINDS. && .LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/... MODELS ARE IN GENERAL AGREEMENT ON BROAD WESTERLY OR WEST- SOUTHWEST FLOW THIS PERIOD...THAT KEEPS ARCTIC AIR BOTTLED UP WELL TO OUR NORTH AND RESULTS IN NEAR NORMAL TEMPERATURES FOR THE PERIOD. DIFFERENCES EMERGE AFTER THURSDAY WITH TIMING OF INDIVIDUAL SHORTWAVES ADDING UNCERTAINTY TO THE FORECAST. IN THE DAILIES...A COLD FRONT WILL CROSS THE AREA WEDNESDAY FOLLOWED BY HIGH PRESSURE AND DRY AIR FOR THURSDAY AND FRIDAY. LOW PRESSURE APPROACHES FROM THE GREAT LAKES FOR SATURDAY AND SUNDAY. && .AVIATION /13Z MONDAY THROUGH FRIDAY/... SHORT TERM...ONE LAST ROUND OF LOCALLY IFR CONDITIONS AND RAIN/SNOW/SLEET WILL CONTINUE INTO THIS MORNING WITH IMPROVING CONDITIONS LATER IN THE DAY. WINDS WILL BE GUSTY OUT OF THE NORTH. LONG TERM... WED...SCT MVFR IN RAIN OR SNOW SHOWERS. SAT - SUN...AREAS OF MVFR IN RAIN AND SNOW WITH LOCAL IFR POSSIBLE. && .MARINE... SHORT TERM...NORTHERLY GALES EXPECTED RIGHT THROUGH TONIGHT AS LOW PRESSURE IS SLOW TO PULL AWAY. LONG TERM... THU...SMALL CRAFT WINDS AND SEAS ARE LIKELY. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...FLOOD WATCH UNTIL 2 PM EDT THIS AFTERNOON FOR MEZ018>028. WINTER WEATHER ADVISORY UNTIL NOON EDT TODAY FOR MEZ012- 018>028. NH...FLOOD WATCH UNTIL 2 PM EDT THIS AFTERNOON FOR NHZ006-008>010- 013-014. WINTER WEATHER ADVISORY UNTIL NOON EDT TODAY FOR NHZ004-006- 008>010-013-014. MARINE...SMALL CRAFT ADVISORY UNTIL NOON EDT TUESDAY FOR ANZ151-153. GALE WARNING UNTIL NOON EDT TUESDAY FOR ANZ150-152-154. && $$ NEAR TERM UPDATE... KIMBLE
AREA FORECAST DISCUSSION
NWS GRAY ME
657 AM EDT MON MAR 31 2014 .SYNOPSIS... LOW PRESSURE WILL MEANDER OFFSHORE TODAY...BEFORE FINALLY PULLING AWAY TONIGHT. HIGH PRESSURE WILL NUDGE IN BEHIND THE LOW FOR TUESDAY. A WEAK FRONT WILL CROSS THE AREA ON WEDNESDAY. HIGH PRESSURE WILL KEEP THINGS DRY THROUGH FRIDAY. LOW PRESSURE WILL TRACK INTO ONTARIO AND QUEBEC NEXT WEEKEND...SPREADING PRECIPITATION ACROSS MAINE AND NEW HAMPSHIRE. && .NEAR TERM /THROUGH TONIGHT/... UPDATE... HAVE UPDATE THE GRIDS TO HIT THE FREEZING RAIN AND SLEET HARD ACROSS SOUTHERN INTERIOR PORTIONS OF THE FORECAST AREA AS DRIVING CONTINUES TO BECOME MORE AND MORE TRECHOROUS. ICE ACCRETION WILL BE A QUARTER TO NEARLY A HALF INCH IN THIS REGION. HAVE ALSO UPDATED TO REMOVE WINTER WEATHER ADVISORIES AND FLOOD WATCHES IN AREAS WHERE THE PRECIP HAS COME TO AN END. PREV DISC... BANDS OF RAIN AND MIXED PRECIPITATION CONTINUE TO ROTATE BACK INTO THE FORECAST AREA FROM THE GULF OF MAINE EARLY THIS MORNING. THIS WILL ALLOW FOR UP TO A QUICK INCH OF ADDITIONAL RAINFALL ON TOP OF THE HEAVY RAINS THAT FELL OVER SOUTHERN LOCATIONS YESTERDAY. LATEST HRRR RUN DEPICTS THIS PRECIPITATION ASSOCIATED WITH THE UPPER LEVEL TROUGH VERY WELL. MUCH OF THE RAINFALL/MIX WILL BE DISSIPATING AROUND 16Z. AREAS OF SLEET AND FREEZING RAIN CONTINUE OVER CENTRAL LOCATIONS...HOWEVER IT HAS BEEN LIGHT. FOR NOW...WILL CONTINUE WITH THE WINTER WEATHER ADVISORIES THIS PACKAGE. WITH PLENTY OF CLOUD COVER AND STRONG...GUSTY NORTHERLY WINDS...WE DO NOT EXPECT THE TEMPERATURES TO RECOVER SIGNIFICANTLY TODAY. && .SHORT TERM /TUESDAY THROUGH TUESDAY NIGHT/... STUBBORN SURFACE AND UPPER LEVEL LOW SLOWLY MOVE OUT TO SEA TONIGHT...ALLOWING FOR CLEARING TO FINALLY TAKE PLACE. SUNSHINE WILL MAKE AN APPEARANCE BACK TO OUR FORECAST AREA ON TUESDAY...WITH MODERATING TEMPERATURES AND MUCH LESS IN THE WAY OF GUSTY WINDS. && .LONG TERM /WEDNESDAY THROUGH SUNDAY/... MODELS ARE IN GENERAL AGREEMENT ON BROAD WESTERLY OR WEST- SOUTHWEST FLOW THIS PERIOD...THAT KEEPS ARCTIC AIR BOTTLED UP WELL TO OUR NORTH AND RESULTS IN NEAR NORMAL TEMPERATURES FOR THE PERIOD. DIFFERENCES EMERGE AFTER THURSDAY WITH TIMING OF INDIVIDUAL SHORTWAVES ADDING UNCERTAINTY TO THE FORECAST. IN THE DAILIES...A COLD FRONT WILL CROSS THE AREA WEDNESDAY FOLLOWED BY HIGH PRESSURE AND DRY AIR FOR THURSDAY AND FRIDAY. LOW PRESSURE APPROACHES FROM THE GREAT LAKES FOR SATURDAY AND SUNDAY. && .AVIATION /12Z MONDAY THROUGH FRIDAY/... SHORT TERM...ONE LAST ROUND OF LOCALLY IFR CONDITIONS AND RAIN/SNOW/SLEET WILL CONTINUE INTO THIS MORNING WITH IMPROVING CONDITIONS LATER IN THE DAY. WINDS WILL BE GUSTY OUT OF THE NORTH. LONG TERM... WED...SCT MVFR IN RAIN OR SNOW SHOWERS. SAT - SUN...AREAS OF MVFR IN RAIN AND SNOW WITH LCL IFR POSSIBLE. && .MARINE... SHORT TERM...NORTHERLY GALES EXPECTED RIGHT THROUGH TONIGHT AS LOW PRESSURE IS SLOW TO PULL AWAY. LONG TERM... THU...SMALL CRAFT WINDS AND SEAS ARE LIKELY. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...FLOOD WATCH UNTIL 2 PM EDT THIS AFTERNOON FOR MEZ018>028. WINTER WEATHER ADVISORY UNTIL NOON EDT TODAY FOR MEZ012- 018>022. NH...FLOOD WATCH UNTIL 2 PM EDT THIS AFTERNOON FOR NHZ006-008>010- 013-014. WINTER WEATHER ADVISORY UNTIL NOON EDT TODAY FOR NHZ004-006- 008>010. MARINE...SMALL CRAFT ADVISORY UNTIL NOON EDT TUESDAY FOR ANZ151-153. GALE WARNING UNTIL NOON EDT TUESDAY FOR ANZ150-152-154. && $$
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
620 AM CDT MON MAR 31 2014 .UPDATE... ISSUED AT 527 AM CDT MON MAR 31 2014 SHOWERS AND EMBEDDED THUNDERSTORMS HAVE EXPANDED NICELY ACROSS WESTERN IOWA ON RADAR. DESPITE THE NUMEROUS LOOKING COVERAGE...1 HOUR METAR OBSERVATIONS ARE STILL ONLY SHOWING MAINLY TRACE AMOUNTS. RAP TRENDS ARE LOOKING MORE PROMISING FOR PRECIPITATION WEST OF THE MISSISSIPPI RIVER...THOUGH...SO FELT IT IS WARRANTED TO RAISE CHANCES SOME. RAP STILL DIMINISHES THE PRECIPITATION BEFORE IT MOVES INTO SOUTHWEST AND CENTRAL WISCONSIN...WHICH MAKES SENSE AS IT RUNS INTO DRY AIR AND LOW LEVEL JET FORCING MIXES OUT. ALREADY INTRODUCED THE POTENTIAL FOR SOME THUNDER PRIOR TO 15Z WEST OF HIGHWAY 52. LOOKS LIKE THE ELEVATED INSTABILITY AND FORCING WANES THEREAFTER. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 342 AM CDT MON MAR 31 2014 A VARIETY OF IMPACTS EXIST IN THE SHORT TERM FROM AN APPROACHING NEGATIVELY TILTED SHORTWAVE. HAVE TRIED TO EXPLAIN THEM THE BEST IN AN ORGANIZED FASHION BELOW. CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS SHOWED A DEEP TROUGH JUST OFF THE U.S. WEST COAST...A NEGATIVELY TILTED VIGOROUS SHORTWAVE OVER NORTHEAST COLORADO...AND RIDGING FROM LOUISIANA INTO MICHIGAN. PLENTIFUL UPPER LEVEL MOISTURE ON WATER VAPOR WAS STREAMING FROM THE CENTRAL PLAINS INTO THE FORECAST AREA AHEAD OF THE VIGOROUS SHORTWAVE...MANIFESTING ITSELF AS SCT-BKN CIRRUS. BELOW THESE CLOUDS...A DRY AIRMASS EXISTS AS SEEN ON A 00Z 700MB AND 850MB RAOB PLOT...WITH DEWPOINT DEPRESSIONS OF 10-20C FROM THE FORECAST AREA SOUTHWEST THROUGH THE CENTRAL PLAINS. SURFACE DEWPOINTS ARE INCREASING IN THE SAME AREA...HOWEVER...NOW ABOUT 5-15 DEGREES HIGHER. THIS INCREASE WAS DUE TO A SOUTHWESTERLY 925MB WIND OF 40-55 KT FROM THE FORECAST AREA DOWN INTO TEXAS...HELPING TO BRING GULF OF MEXICO MOISTURE NORTHWARD. THE WINDS ARE ALSO HOLDING TEMPERATURES UP WITH READINGS MAINLY IN THE 40S. 925MB TEMPS WERE ANALYZED PER RAP AT 08Z OF 9-13C...NEARLY IDENTICAL TO 00Z RAOBS. TO THE WEST...A 988MB LOW WAS LOCATED JUST EAST OF ALLIANCE NEBRASKA. A NARROW BAND OF SHOWERS WERE TRYING TO DEVELOP OVER CENTRAL NEBRASKA EAST OF THIS LOW...ASSOCIATED WITH 310K ISENTROPIC LIFT. THIS PUTS THE SHOWERS ROOTED AROUND 600MB. HOWEVER...THE AFOREMENTIONED LOWER LEVEL DRY AIR HAS KEPT RAIN FROM REACHING THE GROUND. SYNOPTIC OVERVIEW...500MB HEIGHT PROGS FROM MODELS ARE NEARLY IDENTICAL NOW...BOTH IN TIMING AND STRENGTH...FOR THE TRACK OF THE VIGOROUS SHORTWAVE CURRENTLY IN NORTHEAST COLORADO. OVERALL TREND OVER THE PAST WEEK FROM MODELS WAS A SLOWER...DEEPER AND MORE NORTHWEST TRACK. CURRENT CONSENSUS TRACKS THE SHORTWAVE ACROSS WATERTOWN SD LATE THIS AFTERNOON...AND INTO THE DULUTH MN AREA BY 12Z TUE. THE ASSOCIATED SURFACE LOW CURRENTLY IN WESTERN NEBRASKA TAKES NEARLY THE SAME ROUTE...WITH THE PRESSURE WEAKENING TONIGHT AS THE LOW BEGINS TO OCCLUDE. PRECIPITATION...THE TRACK OF THE SURFACE/500MB FEATURES ARE GENERALLY NOT FAVORABLE FOR PRECIPITATION FOR THE FORECAST AREA...ESPECIALLY WITH ALL THE DRY AIR IN PLACE. IF THERE WAS MORE GULF OF MEXICO MOISTURE TO WORK WITH...SAY DEWPOINTS IN THE 50S...THIS MIGHT BE A DIFFERENT STORY. HOWEVER...MODELS STILL CONTINUE TO INDICATE 3 WAVES OF POTENTIAL PRECIPITATION... 1. THE FIRST IS ASSOCIATED WITH THE 310K ISENTROPIC LIFT IN CENTRAL NEBRASKA. THIS LIFT LOOKS TO TRACK NORTHEAST ACROSS THE AREA TODAY. THE PLENTIFUL LOW TO MID LEVEL DRY AIR IN PLACE MAY MAKE IT TOUGH FOR PRECIPITATION TO OCCUR. IN FACT...OVERALL MODEL TRENDS CONTINUE TO SUGGEST LESS AND LESS PRECIPITATION WITH THIS FIRST WAVE...WITH THE REGIONAL CANADIAN AND TO SOME DEGREE THE RAP EVEN SUGGESTING DRY. HAVE LOWERED CHANCES TO 20-30 WITH THIS WAVE. 2. THE SECOND WAVE OF POSSIBLE PRECIPITATION COMES DURING THE EVENING HOURS ASSOCIATED WITH THE LOWS COLD FRONT. THERES A GOOD MODEL CONSENSUS FOR A NARROW LINE OF SCT-BKN SHOWERS TO DEVELOP NEAR I-35 NEAR 00Z...CORRELATING WELL WITH AN AXIS OF WEAK TO MODERATE 0- 2KM MOISTURE CONVERGENCE AND THE LEFT EXIT REGION OF AN UPPER JET. 31.00Z NAM SOUNDINGS SHOW A BRIEF 1 HOUR PERIOD OF THE SHOWERS... WHERE ALSO CAPE ROOTED ABOVE 850MB CLIMBS TO 200-300 J/KG. THIS CAPE AND FORCING SHOULD BE ENOUGH TO GENERATE SOME ISOLATED THUNDER. GIVEN LIKELY INVERTED-V SOUNDING AND 850MB WINDS OF 45-50 KT...THE SHOWERS AND THUNDERSTORMS COULD PRODUCE STRONG TO POSSIBLY EVEN DAMAGING WIND GUSTS. AGAIN...THIS WILL BE ISOLATED. 3. THE FINAL WAVE OF PRECIPITATION IS THE COLD CONVEYOR BELT OF SNOW WRAPPING AROUND THE SYSTEM...POSSIBLY IMPACTING THE FORECAST AREA AFTER MIDNIGHT. MODELS CONTINUE TO TREND MORE AND MORE NORTHWEST WITH THE REACH OF THE COLD CONVEYOR. AS IT STANDS NOW...LOCATIONS MAINLY NORTHWEST OF A LINE FROM AUSTIN MN TO WAUSAU WI LOOK TO SEE THE SNOW. IN ADDITION...THE SNOW MAY NOT ARRIVE UNTIL AFTER 09Z. AS SUCH...ANY ACCUMULATIONS PRIOR TO 12Z WILL BE VERY LIGHT. TEMPERATURES...925MB READINGS ARE PROGGED TO MOSTLY HOLD IN THE 9- 13C RANGE THROUGHOUT THE DAY...WARMEST TOWARDS THE LATE AFTERNOON AT TIME OF PEAK MIXING. THE WARMER START TO THE DAY PLUS LIMITED IMPACT FROM PRECIPITATION WOULD SUPPORT A WARMER SCENARIO. IN ADDITION...IT APPEARS WE SHOULD HAVE SOME SUN BOTH EARLY IN THE DAY AND AGAIN LATER IN THE AFTERNOON. WITH A BREEZY SOUTH WIND AIDING IN ADVECTING WARMER AIR IN FROM THE SOUTH TOO...SEEMS LIKE A SITUATION TO LEAN TOWARDS THE WARMER SIDE OF GUIDANCE. DO THINK...THOUGH...THE MET SHOWING 70-71 FOR BLACK RIVER FALLS...WINONA AND BOSCOBEL IS A BIT TOO AMBITIOUS. READINGS WILL REALLY TAKE A TUMBLE TONIGHT AS COLD AIR WRAPS AROUND THE SURFACE LOW. BY 12Z TUE...925MB TEMPS ARE PROGGED BETWEEN -5 AND -7C. A 30 DEGREE TEMPERATURE DROP IS POSSIBLE BETWEEN 00Z AND 12Z. WINDS...925MB WINDS OF 30-40 KT HOLD NEARLY STEADY THROUGH MUCH OF THE DAY...BUT IT DOES APPEAR THESE SHOULD PICK UP TOWARDS 45 KT AS THE LOW AND FRONT NEAR. THE STRONGEST WINDS STILL LOOK TO OCCUR ALONG/SOUTH OF I-90. THE DAYTIME MIXING PLUS ISALLOBARIC HELP SHOULD PUSH WIND GUSTS TOWARDS THE 35-45 MPH RANGE. CANNOT RULE OUT SOME HIGHER GUSTS. THEN WE HAVE THE COLD FRONTAL PASSAGE TONIGHT WITH 925MB WINDS ALSO 30-40 KT AIDED TOO BY A PRESSURE RISE. MUCH OF THIS SHOULD EASILY MIX DOWN...RESULTING IN GUSTS OF 30-40 MPH WITH MAYBE SOME HIGHER ONES TOWARDS 45 MPH. AFTER COLLABORATION WITH MPX...DMX...DVN AND MKX...SETTLED ON A WIND ADVISORY FOR MOSTLY THE COUNTIES ALONG/WEST OF US-52. THIS ADVISORY MAY NEED EXPANSION TO THE EAST INTO FAR SOUTHWEST WI DURING THE DAY SHIFT. FOR NOW PUT THESE COUNTIES IN AN SPS. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 342 AM CDT MON MAR 31 2014 ACTIVE WEATHER CONTINUES AND WE REALLY NEED TO WATCH THURSDAY NIGHT AND FRIDAY CLOSELY. MODELS HAVE TRENDED A LITTLE FASTER IN EXITING THE VIGOROUS SHORTWAVE TROUGH AND SURFACE LOW TO THE NORTHEAST. AS SUCH...HAVE SPED UP THE EXITING OF THE COLD CONVEYOR BELT SNOW AND BRINGING IN CLEARING QUICKER. WITH A FASTER EXIT...IT APPEARS THOSE LOCATIONS THAT DO SEE SNOW WILL SEE VERY LITTLE. VERY WINDY CONDITIONS TO START OFF THE DAY...ESPECIALLY ACROSS SOUTHEAST MN WHERE A SECONDARY COLD FRONT PASSES...SHOULD SLOWLY DIMINISH THROUGH THE DAY. BETTER SHOT TO LIGHTEN UP THE WINDS COMES TUESDAY NIGHT AS A RIDGE OF HIGH PRESSURE BUILDS IN FOR LOCATIONS NORTH OF I-90. THE NEXT CONCERN ON THE HORIZON INVOLVES THE DEEP UPPER TROUGH OFF THE PACIFIC NORTHWEST COAST. SUBJECTIVELY...THAT TROUGH LOOKS A LOT MEANER THAN THE ONE COMING INTO THE PLAINS RIGHT NOW. MODELS ARE IN VERY GOOD AGREEMENT DIGGING THIS FEATURE INTO THE SOUTHWESTERN U.S. ON WEDNESDAY...CAUSING RIDGING AND A WARM ADVECTION PATTERN TO DEVELOP DOWNSTREAM FROM THE GULF COAST INTO THE LOWER GREAT LAKES. THE BIG PROBLEM HERE IS THAT THE WARM ADVECTION PATTERN MOSTLY OCCURS ALOFT...AS THE LOW LEVELS ARE DOMINATED BY AN EASTERLY FLOW COMING OUT OF COLD...CANADIAN HIGH PRESSURE OVER THE NORTHERN GREAT LAKES AND ONTARIO. THIS SETS THE STAGE FOR POSSIBLE MIXED PRECIPITATION. 31.00Z GFS/NAM/ECMWF ARE ALL INDICATING A LEAD WAVE OF WARM ADVECTION PRECIPITATION IMPACTING MAINLY LOCATIONS SOUTH OF I-90 WEDNESDAY NIGHT INTO THURSDAY MORNING. THERE ARE CONCERNS WITH A WARM LAYER ALOFT AND LOSS OF ICE IN THE CLOUDS TO IMPACT PRECIPITATION TYPE. IN ADDITION...EVAPORATIVE COOLING FROM THE EASTERLY FLOW OF DRY AIR COMBINING WITH THE PRECIPITATION MAY SEND TEMPERATURES AT OR BELOW FREEZING. AS A RESULT...FORECAST INCLUDES A VARIETY OF PRECIPITATION TYPES. ATTENTION THEN TURNS TO THE TROUGH WHICH THE GFS/GFS ENSEMBLE/UKMET AND CANADIAN ARE ALL TRENDING TOWARDS THE DEEP ECMWF SOLUTION. THIS TROUGH LIFTS UP INTO THE FORECAST AREA ON FRIDAY...BRINGING WITH IT A MUCH DEEPER PLUME OF GULF MOISTURE ALONG WITH A FAIRLY DEEP SURFACE LOW. THERE ARE INDICATIONS WE COULD SEE ACCUMULATING WET SNOW...PARTICULARLY OVER OUR NORTHWEST...TO MIXED PRECIPITATION AND EVEN HEAVY RAINFALL. THERE MAY EVEN BE SOME THUNDERSTORMS OVER FAR SOUTHWEST WI THURSDAY NIGHT...BUT THE PROBABILITY IS TOO LOW TO INCLUDE AT THIS TIME. NEEDLESS TO SAY...RAISED PRECIPITATION CHANCES INTO THE 60-70 RANGE FOR MOST LOCATIONS THURSDAY NIGHT AND FRIDAY. LOOKS LIKE THE SYSTEM WILL GRADUALLY EXIT THE AREA FRIDAY NIGHT WITH DRIER AND WARMER WEATHER TO FOLLOW FOR THE WEEKEND AS HIGH PRESSURE BUILDS IN. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING) ISSUED AT 620 AM CDT MON MAR 31 2014 STRONG LOW PRESSURE WILL LIFT NORTHEAST OUT OF NEBRASKA AND INTO THE REGION TODAY. A BAND OF SHOWERS AND ISOLATED THUNDERSTORMS WILL MOVE ACROSS THE TAF SITES THIS MORNING. CURRENT THINKING IS THAT KRST STANDS THE HIGHEST CHANCES OF SEEING A LIGHTNING STRIKE OR TWO OUT OF THE ISOLATED THUNDERSTORMS MOVING ACROSS NORTHEAST IOWA PUSHING NORTH INTO SOUTHEAST MINNESOTA. THIS ACTIVITY WILL WEAKEN QUICKLY AS IT MOVES EAST AND RUNS INTO DRIER AIR. KLSE MAY SEE AN ISOLATED SHOWER LATER THIS MORNING. STRONG SOUTH WINDS WILL OCCUR AT THE TAF SITES TODAY WITH SPEEDS OF 18 TO 20 KTS AND GUSTS RANGING FROM 27 TO 35 KTS. A STRONG COLD FRONT WILL PUSH ACROSS THE TAF SITES THIS EVENING WITH WINDS SWITCHING TO THE WEST. ISOLATED SHOWERS AND THUNDERSTORMS ARE POSSIBLE ALONG THE FRONT THIS EVENING. IF THESE STORMS DEVELOP THEY COULD PRODUCE WIND GUSTS OF 45 TO 50 KTS. STRONG WEST/NORTHWEST WINDS WILL CONTINUE THROUGH THE OVERNIGHT HOURS. ALSO...A STRATUS DECK MAY BRING MVFR CONDITIONS TO THE TAF SITES DURING THE OVERNIGHT. && .FIRE WEATHER... ISSUED AT 342 AM CDT MON MAR 31 2014 BREEZY SOUTHERLY WINDS COMBINED WITH TEMPERATURES CLIMBING INTO THE MID 60S THIS AFTERNOON POSES SOME CONCERN FOR FIRE WEATHER. DEWPOINTS ALSO SHOULD MIX A BIT THIS AFTERNOON...PARTICULARLY OVER CENTRAL AND FAR SOUTHWEST WI WHICH SAW THAT HAPPEN YESTERDAY. FUELS ALSO WERE ABLE TO DRY OUT SOME FROM YESTERDAY. HOWEVER...RELATIVE HUMIDITY VALUES ONLY DROP TO A MINIMUM OF 35 PERCENT...PRECLUDING THE NEED FOR ANY FIRE WEATHER HAZARDS. ANOTHER ITEM TO WATCH IS ISOLATED THUNDERSTORMS COMING ACROSS THE AREA THIS EVENING. GIVEN THAT DRY AIR EXISTS BELOW THE CLOUD BASES...THESE THUNDERSTORMS MAY NOT PRODUCE MUCH RAINFALL. THUS...CANNOT RULE OUT SOME DRY LIGHTNING STRIKES. THE STORMS SHOULD ALSO PRODUCE SOME STRONG WINDS...SO IF A FIRE WOULD GET STARTED...THE WIND COULD HELP IT SPREAD A LITTLE. && .HYDROLOGY... ISSUED AT 342 AM CDT MON MAR 31 2014 FLOOD WATCH REMAINS ON TRACK FOR TREMPEALEAU...JACKSON AND CLARK COUNTIES. BOTH THE BLACK AND TREMPEALEAU RIVERS ARE RESPONDING TO THE SNOWMELT THAT HAS OCCURRED YESTERDAY THROUGH NOW. CONTINUED RAPID SNOWMELT OVER THE NEXT 24 HOURS FROM TEMPERATURES PEAKING UP IN THE MID 50S TO LOW 60S WILL ALLOW THE RIVERS TO CONTINUE RISING. IT APPEARS LIKELY THAT FLOOD WARNINGS WILL BE ISSUED SOMETIME TODAY...PARTICULARLY ON THE BLACK SINCE THE TREMPEALEAU RIVER BASIN MAY BE EXHAUSTED OF SNOWMELT. SHOULD BE A CLOSE CALL ON THE TREMPEALEAU AT DODGE...THOUGH. LOOKING AHEAD TO LATER IN THE WEEK...CONCERN IS GROWING OF A POSSIBLE HEAVY RAINFALL EVENT OVER THE SOUTHEAST HALF OF THE AREA THURSDAY NIGHT AND FRIDAY. WE WILL HAVE TO WATCH THIS TIME PERIOD CLOSELY. LUCKILY THERE ISNT GOING TO BE ANY SNOWMELT OVER THAT AREA. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...FLOOD WATCH FROM LATE TONIGHT THROUGH THURSDAY MORNING FOR WIZ029-033-034. MN...WIND ADVISORY FROM 1 PM THIS AFTERNOON TO 10 AM CDT TUESDAY FOR MNZ086-087-094-095. IA...WIND ADVISORY FROM 1 PM THIS AFTERNOON TO 7 AM CDT TUESDAY FOR IAZ008>010-018-019-029. && $$ UPDATE...AJ SHORT TERM...AJ LONG TERM...AJ AVIATION...WETENKAMP FIRE WEATHER...AJ HYDROLOGY...AJ
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
527 AM CDT MON MAR 31 2014 .UPDATE... ISSUED AT 527 AM CDT MON MAR 31 2014 SHOWERS AND EMBEDDED THUNDERSTORMS HAVE EXPANDED NICELY ACROSS WESTERN IOWA ON RADAR. DESPITE THE NUMEROUS LOOKING COVERAGE...1 HOUR METAR OBSERVATIONS ARE STILL ONLY SHOWING MAINLY TRACE AMOUNTS. RAP TRENDS ARE LOOKING MORE PROMISING FOR PRECIPITATION WEST OF THE MISSISSIPPI RIVER...THOUGH...SO FELT IT IS WARRANTED TO RAISE CHANCES SOME. RAP STILL DIMINISHES THE PRECIPITATION BEFORE IT MOVES INTO SOUTHWEST AND CENTRAL WISCONSIN...WHICH MAKES SENSE AS IT RUNS INTO DRY AIR AND LOW LEVEL JET FORCING MIXES OUT. ALREADY INTRODUCED THE POTENTIAL FOR SOME THUNDER PRIOR TO 15Z WEST OF HIGHWAY 52. LOOKS LIKE THE ELEVATED INSTABILITY AND FORCING WANES THEREAFTER. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 342 AM CDT MON MAR 31 2014 A VARIETY OF IMPACTS EXIST IN THE SHORT TERM FROM AN APPROACHING NEGATIVELY TILTED SHORTWAVE. HAVE TRIED TO EXPLAIN THEM THE BEST IN AN ORGANIZED FASHION BELOW. CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS SHOWED A DEEP TROUGH JUST OFF THE U.S. WEST COAST...A NEGATIVELY TILTED VIGOROUS SHORTWAVE OVER NORTHEAST COLORADO...AND RIDGING FROM LOUISIANA INTO MICHIGAN. PLENTIFUL UPPER LEVEL MOISTURE ON WATER VAPOR WAS STREAMING FROM THE CENTRAL PLAINS INTO THE FORECAST AREA AHEAD OF THE VIGOROUS SHORTWAVE...MANIFESTING ITSELF AS SCT-BKN CIRRUS. BELOW THESE CLOUDS...A DRY AIRMASS EXISTS AS SEEN ON A 00Z 700MB AND 850MB RAOB PLOT...WITH DEWPOINT DEPRESSIONS OF 10-20C FROM THE FORECAST AREA SOUTHWEST THROUGH THE CENTRAL PLAINS. SURFACE DEWPOINTS ARE INCREASING IN THE SAME AREA...HOWEVER...NOW ABOUT 5-15 DEGREES HIGHER. THIS INCREASE WAS DUE TO A SOUTHWESTERLY 925MB WIND OF 40-55 KT FROM THE FORECAST AREA DOWN INTO TEXAS...HELPING TO BRING GULF OF MEXICO MOISTURE NORTHWARD. THE WINDS ARE ALSO HOLDING TEMPERATURES UP WITH READINGS MAINLY IN THE 40S. 925MB TEMPS WERE ANALYZED PER RAP AT 08Z OF 9-13C...NEARLY IDENTICAL TO 00Z RAOBS. TO THE WEST...A 988MB LOW WAS LOCATED JUST EAST OF ALLIANCE NEBRASKA. A NARROW BAND OF SHOWERS WERE TRYING TO DEVELOP OVER CENTRAL NEBRASKA EAST OF THIS LOW...ASSOCIATED WITH 310K ISENTROPIC LIFT. THIS PUTS THE SHOWERS ROOTED AROUND 600MB. HOWEVER...THE AFOREMENTIONED LOWER LEVEL DRY AIR HAS KEPT RAIN FROM REACHING THE GROUND. SYNOPTIC OVERVIEW...500MB HEIGHT PROGS FROM MODELS ARE NEARLY IDENTICAL NOW...BOTH IN TIMING AND STRENGTH...FOR THE TRACK OF THE VIGOROUS SHORTWAVE CURRENTLY IN NORTHEAST COLORADO. OVERALL TREND OVER THE PAST WEEK FROM MODELS WAS A SLOWER...DEEPER AND MORE NORTHWEST TRACK. CURRENT CONSENSUS TRACKS THE SHORTWAVE ACROSS WATERTOWN SD LATE THIS AFTERNOON...AND INTO THE DULUTH MN AREA BY 12Z TUE. THE ASSOCIATED SURFACE LOW CURRENTLY IN WESTERN NEBRASKA TAKES NEARLY THE SAME ROUTE...WITH THE PRESSURE WEAKENING TONIGHT AS THE LOW BEGINS TO OCCLUDE. PRECIPITATION...THE TRACK OF THE SURFACE/500MB FEATURES ARE GENERALLY NOT FAVORABLE FOR PRECIPITATION FOR THE FORECAST AREA...ESPECIALLY WITH ALL THE DRY AIR IN PLACE. IF THERE WAS MORE GULF OF MEXICO MOISTURE TO WORK WITH...SAY DEWPOINTS IN THE 50S...THIS MIGHT BE A DIFFERENT STORY. HOWEVER...MODELS STILL CONTINUE TO INDICATE 3 WAVES OF POTENTIAL PRECIPITATION... 1. THE FIRST IS ASSOCIATED WITH THE 310K ISENTROPIC LIFT IN CENTRAL NEBRASKA. THIS LIFT LOOKS TO TRACK NORTHEAST ACROSS THE AREA TODAY. THE PLENTIFUL LOW TO MID LEVEL DRY AIR IN PLACE MAY MAKE IT TOUGH FOR PRECIPITATION TO OCCUR. IN FACT...OVERALL MODEL TRENDS CONTINUE TO SUGGEST LESS AND LESS PRECIPITATION WITH THIS FIRST WAVE...WITH THE REGIONAL CANADIAN AND TO SOME DEGREE THE RAP EVEN SUGGESTING DRY. HAVE LOWERED CHANCES TO 20-30 WITH THIS WAVE. 2. THE SECOND WAVE OF POSSIBLE PRECIPITATION COMES DURING THE EVENING HOURS ASSOCIATED WITH THE LOWS COLD FRONT. THERES A GOOD MODEL CONSENSUS FOR A NARROW LINE OF SCT-BKN SHOWERS TO DEVELOP NEAR I-35 NEAR 00Z...CORRELATING WELL WITH AN AXIS OF WEAK TO MODERATE 0- 2KM MOISTURE CONVERGENCE AND THE LEFT EXIT REGION OF AN UPPER JET. 31.00Z NAM SOUNDINGS SHOW A BRIEF 1 HOUR PERIOD OF THE SHOWERS... WHERE ALSO CAPE ROOTED ABOVE 850MB CLIMBS TO 200-300 J/KG. THIS CAPE AND FORCING SHOULD BE ENOUGH TO GENERATE SOME ISOLATED THUNDER. GIVEN LIKELY INVERTED-V SOUNDING AND 850MB WINDS OF 45-50 KT...THE SHOWERS AND THUNDERSTORMS COULD PRODUCE STRONG TO POSSIBLY EVEN DAMAGING WIND GUSTS. AGAIN...THIS WILL BE ISOLATED. 3. THE FINAL WAVE OF PRECIPITATION IS THE COLD CONVEYOR BELT OF SNOW WRAPPING AROUND THE SYSTEM...POSSIBLY IMPACTING THE FORECAST AREA AFTER MIDNIGHT. MODELS CONTINUE TO TREND MORE AND MORE NORTHWEST WITH THE REACH OF THE COLD CONVEYOR. AS IT STANDS NOW...LOCATIONS MAINLY NORTHWEST OF A LINE FROM AUSTIN MN TO WAUSAU WI LOOK TO SEE THE SNOW. IN ADDITION...THE SNOW MAY NOT ARRIVE UNTIL AFTER 09Z. AS SUCH...ANY ACCUMULATIONS PRIOR TO 12Z WILL BE VERY LIGHT. TEMPERATURES...925MB READINGS ARE PROGGED TO MOSTLY HOLD IN THE 9- 13C RANGE THROUGHOUT THE DAY...WARMEST TOWARDS THE LATE AFTERNOON AT TIME OF PEAK MIXING. THE WARMER START TO THE DAY PLUS LIMITED IMPACT FROM PRECIPITATION WOULD SUPPORT A WARMER SCENARIO. IN ADDITION...IT APPEARS WE SHOULD HAVE SOME SUN BOTH EARLY IN THE DAY AND AGAIN LATER IN THE AFTERNOON. WITH A BREEZY SOUTH WIND AIDING IN ADVECTING WARMER AIR IN FROM THE SOUTH TOO...SEEMS LIKE A SITUATION TO LEAN TOWARDS THE WARMER SIDE OF GUIDANCE. DO THINK...THOUGH...THE MET SHOWING 70-71 FOR BLACK RIVER FALLS...WINONA AND BOSCOBEL IS A BIT TOO AMBITIOUS. READINGS WILL REALLY TAKE A TUMBLE TONIGHT AS COLD AIR WRAPS AROUND THE SURFACE LOW. BY 12Z TUE...925MB TEMPS ARE PROGGED BETWEEN -5 AND -7C. A 30 DEGREE TEMPERATURE DROP IS POSSIBLE BETWEEN 00Z AND 12Z. WINDS...925MB WINDS OF 30-40 KT HOLD NEARLY STEADY THROUGH MUCH OF THE DAY...BUT IT DOES APPEAR THESE SHOULD PICK UP TOWARDS 45 KT AS THE LOW AND FRONT NEAR. THE STRONGEST WINDS STILL LOOK TO OCCUR ALONG/SOUTH OF I-90. THE DAYTIME MIXING PLUS ISALLOBARIC HELP SHOULD PUSH WIND GUSTS TOWARDS THE 35-45 MPH RANGE. CANNOT RULE OUT SOME HIGHER GUSTS. THEN WE HAVE THE COLD FRONTAL PASSAGE TONIGHT WITH 925MB WINDS ALSO 30-40 KT AIDED TOO BY A PRESSURE RISE. MUCH OF THIS SHOULD EASILY MIX DOWN...RESULTING IN GUSTS OF 30-40 MPH WITH MAYBE SOME HIGHER ONES TOWARDS 45 MPH. AFTER COLLABORATION WITH MPX...DMX...DVN AND MKX...SETTLED ON A WIND ADVISORY FOR MOSTLY THE COUNTIES ALONG/WEST OF US-52. THIS ADVISORY MAY NEED EXPANSION TO THE EAST INTO FAR SOUTHWEST WI DURING THE DAY SHIFT. FOR NOW PUT THESE COUNTIES IN AN SPS. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 342 AM CDT MON MAR 31 2014 ACTIVE WEATHER CONTINUES AND WE REALLY NEED TO WATCH THURSDAY NIGHT AND FRIDAY CLOSELY. MODELS HAVE TRENDED A LITTLE FASTER IN EXITING THE VIGOROUS SHORTWAVE TROUGH AND SURFACE LOW TO THE NORTHEAST. AS SUCH...HAVE SPED UP THE EXITING OF THE COLD CONVEYOR BELT SNOW AND BRINGING IN CLEARING QUICKER. WITH A FASTER EXIT...IT APPEARS THOSE LOCATIONS THAT DO SEE SNOW WILL SEE VERY LITTLE. VERY WINDY CONDITIONS TO START OFF THE DAY...ESPECIALLY ACROSS SOUTHEAST MN WHERE A SECONDARY COLD FRONT PASSES...SHOULD SLOWLY DIMINISH THROUGH THE DAY. BETTER SHOT TO LIGHTEN UP THE WINDS COMES TUESDAY NIGHT AS A RIDGE OF HIGH PRESSURE BUILDS IN FOR LOCATIONS NORTH OF I-90. THE NEXT CONCERN ON THE HORIZON INVOLVES THE DEEP UPPER TROUGH OFF THE PACIFIC NORTHWEST COAST. SUBJECTIVELY...THAT TROUGH LOOKS A LOT MEANER THAN THE ONE COMING INTO THE PLAINS RIGHT NOW. MODELS ARE IN VERY GOOD AGREEMENT DIGGING THIS FEATURE INTO THE SOUTHWESTERN U.S. ON WEDNESDAY...CAUSING RIDGING AND A WARM ADVECTION PATTERN TO DEVELOP DOWNSTREAM FROM THE GULF COAST INTO THE LOWER GREAT LAKES. THE BIG PROBLEM HERE IS THAT THE WARM ADVECTION PATTERN MOSTLY OCCURS ALOFT...AS THE LOW LEVELS ARE DOMINATED BY AN EASTERLY FLOW COMING OUT OF COLD...CANADIAN HIGH PRESSURE OVER THE NORTHERN GREAT LAKES AND ONTARIO. THIS SETS THE STAGE FOR POSSIBLE MIXED PRECIPITATION. 31.00Z GFS/NAM/ECMWF ARE ALL INDICATING A LEAD WAVE OF WARM ADVECTION PRECIPITATION IMPACTING MAINLY LOCATIONS SOUTH OF I-90 WEDNESDAY NIGHT INTO THURSDAY MORNING. THERE ARE CONCERNS WITH A WARM LAYER ALOFT AND LOSS OF ICE IN THE CLOUDS TO IMPACT PRECIPITATION TYPE. IN ADDITION...EVAPORATIVE COOLING FROM THE EASTERLY FLOW OF DRY AIR COMBINING WITH THE PRECIPITATION MAY SEND TEMPERATURES AT OR BELOW FREEZING. AS A RESULT...FORECAST INCLUDES A VARIETY OF PRECIPITATION TYPES. ATTENTION THEN TURNS TO THE TROUGH WHICH THE GFS/GFS ENSEMBLE/UKMET AND CANADIAN ARE ALL TRENDING TOWARDS THE DEEP ECMWF SOLUTION. THIS TROUGH LIFTS UP INTO THE FORECAST AREA ON FRIDAY...BRINGING WITH IT A MUCH DEEPER PLUME OF GULF MOISTURE ALONG WITH A FAIRLY DEEP SURFACE LOW. THERE ARE INDICATIONS WE COULD SEE ACCUMULATING WET SNOW...PARTICULARLY OVER OUR NORTHWEST...TO MIXED PRECIPITATION AND EVEN HEAVY RAINFALL. THERE MAY EVEN BE SOME THUNDERSTORMS OVER FAR SOUTHWEST WI THURSDAY NIGHT...BUT THE PROBABILITY IS TOO LOW TO INCLUDE AT THIS TIME. NEEDLESS TO SAY...RAISED PRECIPITATION CHANCES INTO THE 60-70 RANGE FOR MOST LOCATIONS THURSDAY NIGHT AND FRIDAY. LOOKS LIKE THE SYSTEM WILL GRADUALLY EXIT THE AREA FRIDAY NIGHT WITH DRIER AND WARMER WEATHER TO FOLLOW FOR THE WEEKEND AS HIGH PRESSURE BUILDS IN. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 1140 PM CDT SUN MAR 30 2014 SEVERAL DETAILS TO DEPICT IN THIS SET OF FORECASTS. THE FIRST IS THE WINDS AND ASSOCIATED GUSTS FOR MONDAY. ONCE THE INVERSION BEGINS TO MIX OUT MONDAY MORNING...STRONG WIND SPEEDS WILL EXIST IN THE MIXED LAYER TO GET BROUGHT DOWN TO THE SURFACE. THE 31.00Z NAM BUFKIT SOUNDINGS SHOW THE POTENTIAL FOR GUSTS TO REACH INTO THE MID 30 KNOT RANGE AT KRST MONDAY AFTERNOON AND TO AROUND 30 KNOTS AT KLSE. THESE WINDS WILL DIMINISH SOME LATE IN THE AFTERNOON OR EARLY EVENING AHEAD OF THE APPROACHING COLD FRONT. THERE IS A CHANCE FOR SOME FAST MOVING ELEVATED SHOWERS TO DEVELOP MONDAY MORNING ON THE NOSE OF THE RETURNING LOW LEVEL MOISTURE FROM THE GULF. NOT EXPECTING THESE TO LAST VERY LONG BUT FEEL THE WINDS ARE MORE IMPORTANT FOR TIMING...SO WILL SHOW A LONGER WINDOW OF A SHOWER CHANCE THAN WILL LIKELY OCCUR. A SECOND CHANCE FOR SOME SHOWERS...MAYBE EVEN A THUNDERSTORM...WILL COME AS THE COLD FRONT MOVES THROUGH DURING THE EARLY EVENING. THE CAPE IS ONLY ABOUT 200 J/KG FOR AN HOUR OR TWO AND CONFIDENCE ON THIS ACTUALLY PRODUCING THUNDER IS NOT HIGH ENOUGH TO INCLUDE IN THE FORECAST AT THIS TIME. ONCE THE COLD FRONT COMES THROUGH...THE WINDS WILL SWITCH AROUND TO THE SOUTHWEST BEHIND IT AND REMAIN GUSTY. GOOD LOW LEVEL LAPSE RATES BEHIND THE FRONT WITH STRONG COLD AIR ADVECTION WILL MAINTAIN GUSTS TO AROUND 30 KNOTS. && .FIRE WEATHER... ISSUED AT 342 AM CDT MON MAR 31 2014 BREEZY SOUTHERLY WINDS COMBINED WITH TEMPERATURES CLIMBING INTO THE MID 60S THIS AFTERNOON POSES SOME CONCERN FOR FIRE WEATHER. DEWPOINTS ALSO SHOULD MIX A BIT THIS AFTERNOON...PARTICULARLY OVER CENTRAL AND FAR SOUTHWEST WI WHICH SAW THAT HAPPEN YESTERDAY. FUELS ALSO WERE ABLE TO DRY OUT SOME FROM YESTERDAY. HOWEVER...RELATIVE HUMIDITY VALUES ONLY DROP TO A MINIMUM OF 35 PERCENT...PRECLUDING THE NEED FOR ANY FIRE WEATHER HAZARDS. ANOTHER ITEM TO WATCH IS ISOLATED THUNDERSTORMS COMING ACROSS THE AREA THIS EVENING. GIVEN THAT DRY AIR EXISTS BELOW THE CLOUD BASES...THESE THUNDERSTORMS MAY NOT PRODUCE MUCH RAINFALL. THUS...CANNOT RULE OUT SOME DRY LIGHTNING STRIKES. THE STORMS SHOULD ALSO PRODUCE SOME STRONG WINDS...SO IF A FIRE WOULD GET STARTED...THE WIND COULD HELP IT SPREAD A LITTLE. && .HYDROLOGY... ISSUED AT 342 AM CDT MON MAR 31 2014 FLOOD WATCH REMAINS ON TRACK FOR TREMPEALEAU...JACKSON AND CLARK COUNTIES. BOTH THE BLACK AND TREMPEALEAU RIVERS ARE RESPONDING TO THE SNOWMELT THAT HAS OCCURRED YESTERDAY THROUGH NOW. CONTINUED RAPID SNOWMELT OVER THE NEXT 24 HOURS FROM TEMPERATURES PEAKING UP IN THE MID 50S TO LOW 60S WILL ALLOW THE RIVERS TO CONTINUE RISING. IT APPEARS LIKELY THAT FLOOD WARNINGS WILL BE ISSUED SOMETIME TODAY...PARTICULARLY ON THE BLACK SINCE THE TREMPEALEAU RIVER BASIN MAY BE EXHAUSTED OF SNOWMELT. SHOULD BE A CLOSE CALL ON THE TREMPEALEAU AT DODGE...THOUGH. LOOKING AHEAD TO LATER IN THE WEEK...CONCERN IS GROWING OF A POSSIBLE HEAVY RAINFALL EVENT OVER THE SOUTHEAST HALF OF THE AREA THURSDAY NIGHT AND FRIDAY. WE WILL HAVE TO WATCH THIS TIME PERIOD CLOSELY. LUCKILY THERE ISNT GOING TO BE ANY SNOWMELT OVER THAT AREA. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...FLOOD WATCH FROM LATE TONIGHT THROUGH THURSDAY MORNING FOR WIZ029-033-034. MN...WIND ADVISORY FROM 1 PM THIS AFTERNOON TO 10 AM CDT TUESDAY FOR MNZ086-087-094-095. IA...WIND ADVISORY FROM 1 PM THIS AFTERNOON TO 7 AM CDT TUESDAY FOR IAZ008>010-018-019-029. && $$ UPDATE...AJ SHORT TERM...AJ LONG TERM...AJ AVIATION...04 FIRE WEATHER...AJ HYDROLOGY...AJ
AREA FORECAST DISCUSSION
NWS SAN JOAQUIN VALLEY - HANFORD CA
327 PM PDT MON MAR 31 2014 .SYNOPSIS... A PACIFIC FRONTAL SYSTEM WILL MOVE THROUGH THE AREA TONIGHT AND EARLY TUESDAY. AN AREA OF LOW PRESSURE WILL THEN DROP DOWN THE CALIFORNIA COAST AND MOVE ACROSS SOUTHERN CALIFORNIA TUESDAY NIGHT AND WEDNESDAY. TWO PERIODS OF WET WEATHER WILL OCCUR. HIGH PRESSURE WILL THEN BUILD OVER THE REGION FROM WEDNESDAY THROUGH FRIDAY AS THE STORM EXITS TO THE EAST. && .DISCUSSION... PACIFIC MOISTURE-LADEN STORM CURRENTLY MOVING THROUGH NORTHERN CALIFORNIA AND EXPECTED TO DROP INTO CENTRAL CALIFORNIA LATE THIS AFTERNOON. REGIONAL DOPPLER RADAR IMAGERY SHOWING LIGHT PRECIP ROLLING THROUGH STANISLAUS COUNTY AND EXTENDING INTO MERCED COUNTY. WHILE THE ATMOSPHERE IS STILL TRYING TO MOISTEN-UP... PRECIP WILL BEGIN FALLING BEFORE 500 PM PDT. MOREOVER...WITH THE HEAVIER SHOWERS MOVING INTO SANTA CRUZ/SANTA CLARA...THE CHANCES OF WET WEATHER HITTING MERCED ARE VERY GOOD. AHEAD OF TODAY/S COLD FRONT...WINDS HAVE INCREASED OVER THE WEST SIDE OF THE SAN JOAQUIN VALLEY...THE KERN COUNTY MOUNTAINS AND DESERTS. WILL EXPECT WINDS TO WESTERLY WINDS TO REACH THE 35 TO 45 MPH SPEED THRESHOLD FOR ADVISORY CRITERIA. WHILE STRONG WINDS WILL BE A PROBLEM OVER THE WEST SIDE OF THE SAN JOAQUIN VALLEY...THE LACK OF RAIN OVER THE MOJAVE DESERT WILL MAKE BLOW DUST A BIG PROBLEM FROM RIDGECREST TO ROSAMOND AND BORON. THE HRRR MESOSCALE MODEL HAS THE WINDS INCREASE TO ADVISORY LEVEL AT AROUND 200 PM PDT AND ENDING AT AROUND 10 PM PDT TONIGHT. BEYOND THE WINDS IN THE SHORT TERM...RAIN AND SNOW WILL MOVE INTO THE DISTRICT TONIGHT. BOTH DETERMINISTIC AND PROBABILISTIC MODELS TIME THE ONSET OF PRECIP TO NEAR 400 PM PDT...WITH THE BULK OF THE PRECIP PUSHING THROUGH DURING THE NIGHT. CURRENT ESTIMATES HAVE BETWEEN ONE QUARTER TO ONE HALF OF AN INCH ACROSS THE VALLEY AND 6 TO 10 INCHES OF SNOW OVER THE MOUNTAINS ABOVE 5000 FEET. WHILE SNOW MAY NOT STICK TO THE ROAD OVER TEJON PASS...THE GRAPEVINE WAS INCLUDED IN THE WINTER WEATHER ADVISORY FOR SLICK ROADS MAKING DRIVING DIFFICULT. AFTER TONIGHT/S COLD FRONT...THE MAIN AREA OF ENERGY MOVES INTO CENTRAL CALIFORNIA ON TUESDAY. MODELS STILL SHOWING 500MB TEMP OF MINUS 28 DEG-C PUSHING INTO THE AREA ON TUESDAY BEHIND TONIGHT/S COLD FRONT. WHILE THE BEST POTENTIAL FOR THUNDERSTORMS WILL REMAIN OVER NORTHERN CALIFORNIA...ENOUGH INSTABILITY AND SOME WEAK WIND SHEAR MAY ALLOW FOR A SLIGHT CHANCE OF AFTERNOON CONVECTION ACROSS THE SAN JOAQUIN VALLEY AND ADJACENT FOOTHILLS. BY WEDNESDAY...ANOTHER SHORT WAVE RIDGE MOVES THROUGH THE AREA... ALLOWING CONDITIONS TO TEMPORARY DRY OUT AHEAD OF YET ANOTHER STORM. WEDNESDAY MORNING MAY SEE THE LAST OF THE LINGERING SHOWERS WITH RIDGING EXPECTED LATER IN THE DAY. WHILE CURRENT LONGER RANGE PROGS SHOW THE THIRD STORM MOVING FURTHER NORTH...SOME OF ITS ENERGY COULD REACH THE DISTRICT. CURRENTLY...WILL PLACE A MENTION OF PRECIP OVER THE NORTHERN SECTIONS OF THE DISTRICT AND ACROSS THE SIERRA NEVADA RANGE. WILL CONCENTRATE ON THE NEXT STORM AND FINALIZE THIS NEXT STORM AFTERWARD. && .AVIATION... IFR CONDITIONS WILL DEVELOP FROM NORTH TO SOUTH ACROSS THE SOUTHERN SIERRA NEVADA BY 03Z TUE WITH MOUNTAIN OBSCURATION IN PRECIPITATION BETWEEN 03Z TUE AND 00Z WED. MVFR DUE TO CEILINGS AND PRECIPITATION EXPECTED IN THE CENTRAL SAN JOAQUIN VALLEY...SIERRA FOOTHILLS AND ALONG THE NORTH FACING SLOPES OF THE KERN COUNTY MOUNTAINS FROM 03Z TUESDAY...CONTINUING AT TIMES THROUGH 00Z WEDNESDAY. MVFR CONDITIONS DUE TO PRECIPITATION AND CEILINGS IN THE SOUTHERN SAN JOAQUIN VALLEY THROUGH 18Z TUESDAY. ISOLATED THUNDERSTORMS ARE THEN POSSIBLE AFTER 18Z WED OVER MUCH OF THE SAN JOAQUIN VALLEY AND SIERRA FOOTHILLS. BLOWING DUST...WITH VISIBILITY AT OR BELOW A MILE AT TIMES...IS POSSIBLE OVER THE KERN COUNTY DESERT DUE TO GUSTY WINDS THIS EVENING. OTHERWISE...VFR CONDITIONS CAN BE EXPECTED ELSEWHERE DURING THE NEXT 24 HOURS. ADDITIONALLY...WIND GUSTS OF 35 KNOTS OR GREATER WILL OCCUR THROUGH AND BELOW THE MOUNTAIN PASSES ON THE WEST SIDE OF THE SAN JOAQUIN VALLEY AND IN KERN COUNTY AS WELL AS THE SIERRA CREST THIS EVENING. && .AIR QUALITY ISSUES... NONE. && .CERTAINTY... THE LEVEL OF CERTAINTY FOR DAYS 1 AND 2 IS HIGH. THE LEVEL OF CERTAINTY FOR DAYS 3 THROUGH 7 IS MEDIUM. THIS INFORMATION IS PROVIDED AS PART OF A TRIAL PROJECT CONDUCTED BY THE NATIONAL WEATHER SERVICE SAN JOAQUIN VALLEY - HANFORD. CERTAINTY LEVELS INCLUDE LOW...MEDIUM...AND HIGH. PLEASE VISIT WWW.WEATHER.GOV/HNX/CERTAINTY.PHP /ALL LOWER CASE/ FOR ADDITIONAL INFORMATION AND/OR TO PROVIDE FEEDBACK. && .CLIMATE... RECORDS SITE DATE HI_MAX:YEAR LO_MAX:YEAR HI_MIN:YEAR LO_MIN:YEAR KFAT 03-31 89:1966 50:1967 58:1986 31:1905 KFAT 04-01 90:1966 49:1982 56:1939 32:1975 KFAT 04-02 87:1985 56:1907 57:2011 34:1982 KBFL 03-31 90:2003 50:1925 60:1969 32:1908 KBFL 04-01 88:2011 54:1998 62:1900 32:1917 KBFL 04-02 90:1985 57:1981 60:2002 35:1999 && .HNX WATCHES/WARNINGS/ADVISORIES... WINTER WEATHER ADVISORY FROM 5 PM THIS AFTERNOON TO 5 AM PDT TUESDAY CAZ096-097. WINTER WEATHER ADVISORY FROM 10 PM THIS EVENING TO 8 AM PDT TUESDAY CAZ095. WIND ADVISORY UNTIL 10 PM PDT THIS EVENING CAZ095. WIND ADVISORY UNTIL 10 PM PDT THIS EVENING CAZ089-091. WIND ADVISORY UNTIL 10 PM PDT THIS EVENING CAZ098-099. && $$ PUBLIC...MOLINA AVN/FW...BSO/INIGUEZ SYNOPSIS...BSO WEATHER.GOV/HANFORD
AREA FORECAST DISCUSSION
NWS SACRAMENTO CA
1123 AM PDT Mon Mar 31 2014 .Synopsis... A cold Pacific storm will bring more precipitation to Interior NorCal into Wednesday with snow levels lowering into the foothills tonight into Tuesday. There is the threat of some Valley/Delta thunderstorms this afternoon/evening and again on Tuesday. Later this week, a weak system moves through the region and may bring some light amounts of precipitation. && .Discussion... Cold negative tilt trough with a surface cold front is moving onshore this morning with precipitation spreading through the Coastal Mountains and into the rest of the area by this afternoon. Afternoon/evening thunderstorms in the Valley and Delta are possible. Lightning and visible satellite shows convection already just off the coast of Monterrey this morning. Some stronger storms are beginning to develop right along the coast. Early afternoon thunderstorms may develop with the front. Low level shear behind the front by late afternoon looks relatively strong in the Valley south of Red Bluff, so there is some potential for stronger, rotating storms in the post frontal environment. HRRR model shows a surface Cape bullseye around 350 J/KG, centered roughly around Yuba City. Spotters should be aware of the possibility of some isolated severe thunderstorms late in the day/early evening. Small hail with these cold storms would be the main threat, with locally heavy rain and gusty winds. With decent shear, can not rule out the possibility of a few funnel clouds and even an isolated tornado isn`t out of the question. Winter Storm Warnings for the mountains and advisory for low snow in the foothills is on track. Snow should peak over the coastal mountains this afternoon, this evening over the Sierra. Snow totals of 1-2 feet are possible at higher elevations. Convective threat will continue across the region Tuesday, and appears there will be a conditional severe weather threat once again for the Central Valley depending on any localized surface heating as forecast soundings show increasing vertical wind shear (speed and directional), however ongoing widespread convection with mid-level cold pool aloft overhead (-30C to -32C at 500 mbs) may greatly limit this potential. Upper trough forecast to shift south of the region later Tuesday night into Wednesday with a decreasing threat of showers across NorCal. Short-wave ridging forecast to briefly move over NorCal Wednesday night into Thursday ahead of a much weaker trough moving in for later Thursday. && .Extended Discussion (Friday through Monday) Models differ with strength of short wave trough/low progged to move across the area on Friday. ECMWF-HiRes showing a stronger close upper low while the GFS/GEM progging a weaker trough. Have leaned towards the ADJMRA for this time period for now, advertising slight chance to chance POPs, with best chances of precip expected over the mountains. Models then similar in building upper ridging from EPAC over Interior NorCal through the weekend into Monday with dry weather and warming. High temperatures climb into the mid to upper 70s in the Central Valley towards the end of the extended period with 50s to low 70s for the mountains and foothills. && .Aviation... Deteriorating conditions today as a cold frontal system moves into the area bringing precipitation and gusty winds. For the TAF sites in the Central Valley VFR/MVFR conditions with areas of IFR developing aft 18a. Isold Thunderstorms possible after 22z. Southerly surface wind to 25kts with local gusts up to 35 kts until 03z Tuesday. Over Coastal and Shasta Mountains widespread MVFR/IFR with areas of LIFR conditions and snow levels around 3000 feet lowering to around 2000 ft aft 06z Tuesday. Over Northern Sierra and Western Plumas County IFR/LIFR conditions with snow levels around 4000 ft lowering to around 2500 ft aft 06z Tuesday. Southwest surface wind gusts up to 50 kts possible. && .STO Watches/Warnings/Advisories... winter storm warning until 11 am pdt tuesday west slope northern sierra nevada...western plumas county/lassen park. winter storm warning until 5 am pdt tuesday above 3500 feet in the mountains southwestern shasta county to northern lake county...shasta lake area / northern shasta county. winter weather advisory from 5 pm this afternoon to 5 am pdt tuesday burney basin / eastern shasta county. winter weather advisory from 8 pm this evening to 11 am pdt tuesday above 2500 feet in the clear lake/southern lake county... motherlode...northeast foothills/sacramento valley. && $$
AREA FORECAST DISCUSSION...AVIATION UPDATE
NWS PEACHTREE CITY GA
122 PM EDT MON MAR 31 2014 .UPDATE... /ISSUED AT 1038 AM EDT MON MAR 31 2014/ ONLY CHANGE TO THE FORECAST WILL BE FOR LOWER DEWPOINTS AND RELATIVE HUMIDITIES. VERY DRY JUST OFF THE SURFACE...AND WITH MIXING DEWPOINTS SHOULD DROP SIGNIFICANTLY. MAV/MET APPEAR TOO HIGH IN DEWPOINTS AND THE LATEST RUC APPEARS TO HAVE A BETTER HANDLING AT THE MIXING. 17 && .SHORT TERM /TODAY THROUGH TUESDAY/... /ISSUED AT 350 AM EDT MON MAR 31 2014/ UPPER RIDGE WILL BUILD ACROSS THE SOUTHEAST TODAY. THE RIDGE WILL FLATTEN SOME ON TUESDAY AS THE WEAK TRAILING END OF A SHORT WAVE PASSES OVER THE OHIO VALLEY. SHORT WAVE HAS LIMITED MOISTURE..SO EXPECT NO RAIN WITH IT BUT MAYBE SOME CLOUDS. THERE WILL BE A WARMING TREND AS HEIGHTS RISE AND WINDS COME AROUND TO THE SOUTHWEST. MAV/MET TEMPERATURES ARE CLOSE AND HAVE NOT DEVIATED MUCH. FROST ADVISORY REMAINS IN EFFECT UNTIL 9 AM. 41 .LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/... /ISSUED AT 350 AM EDT MON MAR 31 2014/ HIGH PRESSURE WILL DOMINATE AT THE BEGINNING OF THE LONG TERM AHEAD OF THE NEXT SYSTEM THAT WILL APPROACH LATE WEEK. STILL DIFFERENCES BETWEEN THE GFS AND ECMWF WITH THIS LATE WEEK SYSTEM IN TERMS OF BOTH THE POSITIONING OF FEATURES AND TIMING. ECMWF IS A LITTLE FURTHER NORTH WITH THE SFC LOW AND QUICKER WITH PUSHING THE FRONT THROUGH. BOTH MODELS BRING THE PRECIP IN ON FRIDAY BUT THE ECMWF PUSHES THE FRONT THROUGH BY SATURDAY MORNING. THE GFS ON THE OTHER HAND DOESNT PUSH THE FRONT THROUGH UNTIL LATER ON SATURDAY AND THUS THE GFS APPEARS TO INDICATE A FRIDAY AFTERNOON TO SATURDAY EVENT IN TERMS OF THE MORE ACTIVE WEATHER. FORECAST TRENDS TOWARDS THE SLOWER GFS SOLUTION. GFS SHOWS THE HIGHEST INSTABILITY FRIDAY EVENING WITH 2000 J/KG OF MUCAPE ACROSS NW GA. IN ADDITION IT PEGS AROUND 30 KTS OF LOW LEVEL SHEAR ACROSS N GA. ALTHOUGH THE SHEAR WITH THE SYSTEM DECREASES...INSTABILITY IS ENOUGH FOR STRONG TO SEVERE STORM POTENTIAL FRIDAY THROUGH SATURDAY SO THIS SYSTEM CONTINUES TO NEED TO BE MONITORED. 11 && .FIRE WEATHER... /ISSUED AT 350 AM EDT MON MAR 31 2014/ FUELS HAVE DRIED AND RELATIVE HUMIDITY VALUES DIP TO 25 PERCENT OR LESS FOR AROUND 4 HOURS MOST AREAS THIS AFTERNOON. WINDS SHOULD BE LIGHT SOUTHWEST. HAVE ISSUED A FIRE DANGER STATEMENT FOR THE ENTIRE CWA...ALTHOUGH A FEW AREAS MAY BE BORDERLINE FOR HUMIDITY. 41 && .AVIATION... 18Z UPDATE... VFR CONDITIONS EXPECTED THROUGH THE FORECAST PERIOD. LIGHT SOUTHWEST TO NEAR CALM WINDS THROUGH THE FORECAST. CIRRUS WILL THICKEN ACROSS NORTH GA TONIGHT AND THEN EXIT TUESDAY MORNING. //ATL CONFIDENCE...18Z UPDATE... HIGH ON ALL ELEMENTS. 17 && .PRELIMINARY POINT TEMPS/POPS... ATHENS 76 46 81 52 / 0 0 0 0 ATLANTA 74 52 78 56 / 0 0 0 0 BLAIRSVILLE 73 42 74 47 / 0 0 0 0 CARTERSVILLE 75 43 78 49 / 0 0 0 0 COLUMBUS 75 47 79 54 / 0 0 0 0 GAINESVILLE 73 49 76 54 / 0 0 0 0 MACON 75 41 80 49 / 0 0 0 0 ROME 75 43 78 48 / 0 0 0 0 PEACHTREE CITY 75 40 78 47 / 0 0 0 0 VIDALIA 77 49 82 55 / 0 0 0 0 && .FFC WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
301 PM CDT MON MAR 31 2014 .SYNOPSIS... ISSUED AT 300 PM CDT MON MAR 31 2014 WATER VAPOR IMAGERY SHOWS A NEGATIVELY TILTED UPPER TROF WAS OVER NORTHEAST NE THIS AFTERNOON WITH A DEEP SURFACE LOW OVER EASTERN SOUTH DAKOTA. THE STRONG GRADIENT AROUND THE LOW HAS BEEN SUPPORTING STRONG SOUTH WINDS OVER THE REGION THROUGHOUT THE DAY. A BAND OF SHRA AND ISOLATED TSRA MOVED THROUGH THE WESTERN HALF OF THE CWFA THIS MORNING AND RAPIDLY WEAKENED AS IT REACHED THE MISSISSIPPI RIVER. VISIBLE SATELLITE IMAGERY SHOWED A LARGE DRY/CLEAR SLOT OVER MUCH OF IOWA THIS AFTERNOON. A NARROW N/S ORIENTED CU FIELD JUST AHEAD OF THE COLD FRONT WAS JUST STARTING TO DEVELOP AROUND 19Z. && .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 300 PM CDT MON MAR 31 2014 THE SURFACE LOW AND UPPER TROF ARE FORECAST TO MOVE NORTHEAST TONIGHT AND SHOULD BE OVER THE WESTERN GREAT LAKES/NORTHERN WI BY TUESDAY MORNING. THE LOW WILL DRAG A COLD FRONT THROUGH THE REGION THIS EVENING. STRONG GUSTY SOUTH WINDS WILL CONTINUE THE REST OF THIS AFTERNOON INTO THIS EVENING THEN TURN WESTERLY AFTER THE FRONTAL PASSAGE. WINDS WILL REMAIN STRONG OVER NIGHT WITH GUSTS AROUND 30 MPH EXPECTED...ESPECIALLY NORTH OF INTERSTATE 80. THE LOW WILL BE LIFTING NORTHEAST AWAY FROM THE REGION LATE TONIGHT AND THE STRONGER PRESSURE RISES WILL ALSO BE EAST OF THE AREA BY LATE TONIGHT SO WINDS SHOULD DIMINISH THROUGH THE MORNING HOURS ON TUESDAY. MESO MODELS HAVE BEEN CONSISTENT TODAY IN SHOWING A SECOND LINE OF SHOWERS AND THUNDERSTORMS DEVELOPING LATE THIS AFTERNOON IN THE DRY SLOT OVER CENTRAL IOWA...ALONG THE COLD FRONT. THE MODELS BRING THE PRECIPITATION EAST INTO THE MID MISSISSIPPI VALLEY EARLY THIS EVENING. THIS LOOKS REASONABLE ESPECIALLY WITH THE CU DEVELOPMENT ONGOING OVER CENTRAL/WESTERN IOWA. THE LATEST RAP SHOWS STRONG DEEP LAYER SHEAR OVER THE REGION LATE THIS AFTERNOON AND EARLY THIS EVENING WITH WEAK SURFACE BASED AND ELEVATED CAPES. THIS MAY BE ENOUGH TO SUPPORT SOME ISOLATED STRONG STORMS EMBEDDED IN THE LINE. IF THIS OCCURS THEN THE STRONGER STORMS MAY HAVE POTENTIAL FOR STRONG...POSSIBLY SEVERE WIND GUSTS CONSIDERING THE STRONG ENVIRONMENT WINDS AND DEEP/DRY SUB CLOUD BASE LAYER. LOW WEB BULB ZERO HEIGHTS AROUND 7KFT WOULD ALSO SUPPORT SOME SUB SEVERE HAIL. THE THREAT OF THE STRONGER STORMS IS WEST OF THE MISSISSIPPI RIVER SINCE THE LINE IS EXPECTED TO WEAKEN SHORTLY AFTER SUNSET AS IT NEARS THE MISSISSIPPI. COLDER AIR POURING IN BEHIND THE COLD FRONT LATE TONIGHT WILL DROP TEMPERATURES INTO THE MID 20S TO MID 30S. SOME WRAP AROUND CLOUDS WILL MOVE ACROSS THE NORTHERN THIRD LATE TONIGHT AND LIFT NORTHEAST OUT OF THE AREA TUESDAY MORNING. TEMPERATURES ARE EXPECTED TO REBOUND INTO THE MID 40S TO LOW 50S TUESDAY BASED ON MIXING UP TO 900MB. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 300 PM CDT MON MAR 31 2014 FORECAST FOCUS ON ACTIVE EARLY SPRING PATTERN WITH STRONG SYSTEM MID TO LATE WEEK WITH POTENTIAL FOR ANOTHER ONE EARLY NEXT WEEK. CURRENTLY...AN INTENSE DIGGING UPPER LOW IS SEEN ON WATER VAPOR LOOPS SWIRLING OFF THE WEST COAST. THIS HAS A 130 KNOT UPPER LEVEL JET ON THE BACK SIDE OF THE TROUGH ALONG WITH PLENTY OF COLD AIR CUMULUS...INDICATIVE OF A VERY COLD POCKET ALOFT. TUESDAY NIGHT THROUGH THURSDAY...UPPER TROUGH WILL BE PUSHING INTO THE DESERT SOUTHWEST WITH CYCLOGENESIS BEGINNING TO ORGANIZE IN SOUTHEAST CO. LOW LEVEL JET WILL INCREASE WITH AN EXCELLENT FEED OFF THE WESTERN GULF. WARM FRONT WILL BE LIFTING INTO CENTRAL MO SETTING UP AN IDEAL UPGLIDE OF THE DEEPENING MOISTURE...AND ALLOWING FOR RAIN TO BEGIN SPREADING INTO OUR FAR SOUTHERN COUNTIES BY LATE TUESDAY NIGHT. LIGHT TO MODERATE RAIN WILL SPREAD OVER ALL THE CWA AS THE DAY PROGRESSES ON WEDNESDAY...CONTINUING WEDNESDAY NIGHT. I WILL CONTINUE TO INDICATE HIGH POPS WHICH HAS BEEN A VERY CONSISTENT SIGNAL FOR DAYS NOW. THERE MAY BE A LULL IN THE RAIN ON THURSDAY AS THE BETTER FORCING SHIFTS TO THE WEST AHEAD OF THE MAIN UPPER TROUGH PUSHING INTO THE PLAINS. BELOW NORMAL TEMPERATURES WITH HIGHS IN THE 40S WITH SOME LOWER TO MID 50S FAR SOUTH. LOWS SHOULD BE IN THE 30S DURING THIS PERIOD. THURSDAY NIGHT AND FRIDAY...POTENT NEGATIVELY TILTED UPPER TROUGH ARRIVES WITH THE MAIN DYNAMICS AND LARGE SCALE ASCENT. OPERATIONAL MODELS ARE SIMILAR IN THIS REGARD. COPIOUS MOISTURE IN PLACE SHOULD ALLOW FOR MODERATE TO LOCALLY HEAVY RAINFALL ESPECIALLY THURSDAY NIGHT. THE SURFACE LOW IS TRENDING A BIT SOUTHEAST COMPARED TO PREVIOUS MODEL RUNS. THE ECMWF TAKES THE CENTER OF THE STRONG CYCLONE INTO EASTERN IA TO NORTHERN LAKE MI WHILE THE GFS HAS THE LOW TRACKING INTO EXTREME SOUTHEAST IA AND THEN TO NEAR CHICAGO. EITHER SOLUTION OFFERS THE BULK OF THE PRECIPITATION TO BE IN THE FORM OF RAIN BUT A FEW THUNDERSTORMS ARE POSSIBLE THURSDAY EVENING DEPENDING ON THE LOCATION OF THE WARM FRONT AND AMOUNT OF INSTABILITY. AT THIS POINT IN THE GAME THE DEFORMATION ZONE PRODUCING ACCUMULATING SNOW SHOULD REMAIN NORTHWEST OF THE DVN CWA. WIDESPREAD SOAKING RAINFALL AMOUNTS DURING THIS TUESDAY NIGHT THROUGH FRIDAY TIME FRAME LOOKS TO BE 1 TO 2 INCHES WITH AMOUNTS TO 3 INCHES NOT OUT OF THE QUESTION. (WITH THE MILD TEMPERATURES THE PAST COUPLE OF DAYS THE FROST IS PRETTY MUCH OUT OF THE GROUND SO AS TO ALLOW THE RAIN TO SOAK IN...SO NOT EXPECTING ANY SIGNIFICANT HYDRO ISSUES). THIS UPCOMING WEEKEND INTO EARLY NEXT WEEK...MODERATING TEMPERATURES INTO THE 50S BY SUNDAY WITH THE WEEKEND DRY. HOWEVER...ANOTHER WELL ORGANIZED STORM SYSTEM ARRIVES SUNDAY NIGHT AND MONDAY (ECMWF)...BUT MUCH WEAKER (GFS). IF THE LATEST RUNS VERIFY THEN TEMPERATURES EARLY NEXT WEEK MAY BE TOO WARM AND THE ALL BLEND WILL NEED TO BE LOWERED. CONFIDENCE IS LOW AT THIS POINT AS THE SYSTEM IS STILL A WEEK AWAY. HAASE && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 1243 PM CDT MON MAR 31 2014 DEEP LOW PRESSURE OVER SOUTHEASTERN SOUTH DAKOTA WILL MOVE NORTHEAST INTO THE WESTERN GREAT LAKES BY TUESDAY MORNING. THE LOW WILL DRAG A COLD FRONT THROUGH THE MID MISSISSIPPI VALLEY THIS EVENING. THE STRONG PRESSURE GRADIENT AROUND THE LOW WILL KEEP STRONG SOUTH WINDS OVER THE AREA THIS AFTERNOON. GUSTS OF 30 TO 35KTS WILL BE COMMON. AREAS NORTH OF HIGHWAY 30 COULD SEE GUSTS EXCEED 40KTS LATE THIS AFTERNOON. A NARROW LINE OF SHOWERS AND THUNDERSTORMS IS EXPECTED TO DEVELOP OVER CENTRAL IOWA LATE THIS AFTERNOON AND MOVE EAST REACHING THE MISSISSIPPI RIVER AROUND 03Z. THE STORMS WILL HAVE THE POTENTIAL TO PRODUCE WIND GUSTS IN EXCESS OF 40KTS THROUGH EARLY EVENING. BRIEF MVFR CIGS/VSBSY WILL BE POSSIBLE WITH THE STRONGER STORMS. AFTER THE FRONT MOVES THROUGH THIS EVENING WINDS WILL TURN TO THE WEST AND WILL REMAIN STRONG THROUGH TUESDAY MORNING...THEN GRADUALLY DIMINISH DURING THE LATE MORNING AND EARLY AFTERNOON. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...NONE. IL...NONE. MO...NONE. && $$ SYNOPSIS...DLF SHORT TERM...DLF LONG TERM...HAASE AVIATION...DLF
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1122 AM MDT MON MAR 31 2014 .UPDATE... ISSUED AT 846 AM MDT MON MAR 31 2014 HAVE RECEIVED MULTIPLE REPORTS OF NEAR ZERO VISIBILITY FROM RAWLINS...RED WILLOW...SHERIDAN AND DECATUR COUNTIES THIS MORNING. LOOKING AT SATELLITE IMAGERY THERE IS NOTICEABLE STREAKS OF DUST EVIDENT OVER THESE COUNTIES. EXPECT THE LOW VISIBILITIES TO PROGRESS EAST INTO NORTON AND GRAHAM COUNTIES THIS MORNING SO CHOSE TO INCLUDE THEM IN THE DUST STORM WARNING AS WELL. ALSO INCLUDED HITCHCOCK COUNTY BASED ON SATELLITE IMAGERY OF DUST STEAKS. WOULD EXPECT THE DUST TO DIMINISH DURING THE AFTERNOON AS THE STRONGER WINDS MOVE FURTHER EAST. THE WORST VISIBILITIES WILL BE SOUTH OF TILLED FIELDS AND DIRT ROADS. UPDATE ISSUED AT 811 AM MDT MON MAR 31 2014 EXPANDED HIGH WIND WARNING TO INCLUDE NORTON AND GRAHAM COUNTIES SINCE NORTON IS CURRENTLY REPORTING WIND GUSTS OF 53 KNOTS. UPDATE ISSUED AT 737 AM MDT MON MAR 31 2014 HAVE HAD AT ATLEAST A COUPLE REPORTS OF WIND GUSTS AROUND 60 MPH THIS MORNING...ONE AT WRAY ABOUT 90 MINUTES AGO AND ANOTHER AT ATWOOD ABOUT 11 MINUTES AGO. HAVE ALSO HAD 2 REPORTS JUST UNDER WARNING CRITERIA...ONE AT YUMA AND ANOTHER AT MCCOOK. THESE REPORTS DO MAKE SINCE GIVEN THE POSITION OF THE 500MB TROUGH WHICH HAS ITS BASE OVER THE NORTHERN HALF OF THE AREA THIS MORNING WHICH IS WHERE THE STRONGEST SUBSIDENCE WILL BE. LOCATIONS SOUTH OF I-70 SHOULD REMAIN BELOW WARNING CRITERIA SINCE THE BASE OF THE 500MB TROUGH WILL NOT MOVE THAT FAR SOUTH. ALSO EXCLUDED NORTON AND GRAHAM COUNTIES SINCE THE 500MB TROUGH LIFTS NORTHEAST BEFORE IT GETS TO THOSE TWO COUNTIES. EXPECT WINDS TO DECLINE DURING THE EARLY AFTERNOON AS THE STRONGER WINDS MOVE EAST OF THE AREA. WILL MORE THAN LIKELY DOWNGRADE THE CURRENT WARNING TO AN ADVISORY BY THEN...BUT FOR SIMPLICITY KEPT THE DURATION OF THE WARNING THE SAME AS THE ADVISORY. UPDATE ISSUED AT 510 AM MDT MON MAR 31 2014 HAVE ADJUSTED THE START TIME OF THE WIND ADVISORY 2 HOURS SOONER (BASICALLY NOW) GIVEN WIND GUSTS OF 60 MPH 1W YUMA AND 49 MPH IN WRAY AT THE AWOS. AM CONCERNED ABOUT REACHING HIGH WIND WARNING CRITERIA ACROSS THE NORTH CENTRAL AND NORTHWEST PORTIONS OF THE AREA GENERALLY NORTH OF THE INTERSTATE. RUC 800MB WINDS INCREASE THIS MORNING WITH 50-60KTS THROUGH 17Z OR SO ON THE BACKSIDE OF DEPARTING UPPER SYSTEM. HOWEVER...THIS AREA ALSO UNDER MORE CLOUDINESS WHICH COULD LIMIT FULL MIXING BUT ON THE OTHER HAND RADAR RETURNS SUGGEST SOME LIGHT SHOWERS OR VIRGA SO THE STRONGER WINDS MAY COME FROM THAT. WILL WATCH CLOSELY FOR THE NEXT HOUR AND SEE WHAT HAPPENS AT WRAY AWOS (K2V5). && .SHORT TERM...(TODAY THROUGH WEDNESDAY NIGHT) ISSUED AT 300 AM MDT MON MAR 31 2014 TODAY-TONIGHT...UPPER DISTURBANCE THAT HAS BEEN ADVERTISED THE PAST FEW DAYS IS CURRENTLY OVER NORTHEAST COLORADO. A SURFACE LOW IS DEEPENING OVER NORTH CENTRAL NEBRASKA. WEST TO SOUTHWEST WINDS ARE BREEZY TO WINDY AT TIMES. FOR THE REST OF TODAY AND INTO TONIGHT THE UPPER LOW AND ASSOCIATED SFC LOW WILL LIFT NORTHEAST REACHING EASTERN SOUTH DAKOTA BY THE END OF THE DAY CONTINUING TOWARD THE GREAT LAKES TONIGHT. WEATHER CONCERNS DURING THIS PERIOD ARE WINDS AND THREAT OF BLOWING DUST. BLENDED MAV/MET/LAMP WINDS ALONG WITH OUTPUT FROM LOCAL WIND PROGRAM. THIS IS PRODUCING WIND GUSTS GENERALLY IN THE 36KT TO 46KT RANGE...HIGHEST ALONG AND NORTH OF THE INTERSTATE. FOR NOW WIND ADVISORY LOOKS GOOD BUT WILL NEED TO WATCH AS WE ARE CLOSE TO WARNING CRITERIA (50KTS) GENERALLY ALONG AND NORTH OF THE KS/NE BORDER. THESE WINDS WILL LIKELY CAUSE AREAS OF BLOWING DUST AND CURRENT FORECAST HAS THIS ALREADY ADVERTISED. HIGH TEMPERATURES IN THE 50S TO LOW 60S...WARMEST ACROSS THE EAST AND SOUTHERLY PARTS OF THE AREA. LOWS IN THE MID 20S TO AROUND 30. AM CONCERNED A BIT THAT MID AND HIGH CLOUDS MAY KEEP TEMPS A BIT WARMER DESPITE SFC HIGH NOSING INTO THE AREA. TUESDAY-TUESDAY NIGHT...SFC HIGH SLOWLY MOVES EAST WITH LOW PRESSURE DEVELOPING ALONG THE FRONT RANGE. THIS WILL CREATE AN INCREASING PRESSURE GRADIENT ACROSS THE AREA WITH SOUTH/SOUTHEAST WINDS GUSTING 35 TO PERHAPS 40 MPH...MAINLY WEST OF A LINE FROM BENKELMAN TO COLBY AND LEOTI WITH STRONGEST WINDS NEAR THE CO/KS BORDER. WINDS BECOME EAST/NORTHEAST 10-15 MPH TUESDAY NIGHT. A NARROW SLIVER OF INSTABILITY DEVELOPS ALONG THE CO/KS BORDER TUESDAY AFTERNOON WITH AN INCREASE IN MAINLY MID LEVEL CLOUDINESS. FEEL THAT THIS COMBINED WITH SOME LOW LEVEL WIND CONVERGENCE WILL BE ENOUGH TO AT LEAST WARRANT ISOLATED THUNDERSTORMS MAINLY IN YUMA COUNTY. HIGH TEMPERATURES IN THE LOW TO MID 50S EAST...UPPER 50S WITH LOW 60S ACROSS THE WEST. LOWS IN THE UPPER 20S WEST TO MID 30S EAST. WEDNESDAY-WEDNESDAY NIGHT...FOCUS NOW TURNS TO UPPER TROUGH WHICH BY THE END OF THE DAY WEDNESDAY SHOULD BE ACROSS THE INTERMOUNTAIN WEST WITH A SLOW EASTWARD PROGRESSION WEDNESDAY NIGHT. AT THE SFC EAST/NORTHEAST WINDS WILL SLOWLY INCREASE THROUGH DAY THEN SHIFT TO THE NORTH/NORTHEAST DURING THE NIGHT AS LOW PRESSURE OVER SOUTHEAST COLORADO SLIDES SOUTH INTO THE TEXAS PANHANDLE. HIGH TEMPERATURES GENERALLY IN THE 50S WITH PERHAPS A 60 DEGREE READING ACROSS THE FAR SOUTH AND SOUTHWEST. LOWS GENERALLY IN THE LOW TO MID 30S. PRECIPITATION CHANCES INCREASE A BIT LATE WEDNESDAY AFTERNOON AND CONTINUE TO INCREASE WEDNESDAY NIGHT WITH MOST LIKELY PRECIPITATION TYPE BEING RAIN THROUGH MIDNIGHT THEN A TRANSITION TO SNOW FOR THE NORTHWEST HALF OF THE AREA. ANY ACCUMULATION LOOKS TO BE UNDER AN INCH AT PRESENT TIME. .LONG TERM...(THURDAY THROUGH SUNDAY) ISSUED AT 300 AM MDT MON MAR 31 2014 THURSDAY-THURSDAY NIGHT...ECMWF/GFS/GEFS ARE ACTUALLY IN BETTER AGREEMENT ON TROUGH PASSAGE THU...WHILE GEM IS STILL SLOWER/STRONGER/FURTHER NORTH. FINER DETAILS BETWEEN MODELS CONTINUE TO DIFFERENCES...HOWEVER OVERALL TREND SEEMS TO FAVOR THE NORTHERN PART OF OUR CWA FOR DEVELOPMENT OF A BAND OF PRECIP AND COOLER TEMPS. I BUMPED POPS UP (50 PERCENT NORTH) AND LOWERED HIGHS (40-45F). BASED ON THE AMOUNT OF CAA...AND POSSIBLE CLOUDS/PRECIP THIS MAY STILL BE TOO WARM. PRECIP TYPE WILL BE TRICKY AS TEMP PROFILES WOULD GENERALLY INDICATE SATURATION TO WET BULB TEMP WOULD SUPPORT AT LEAST A MIX OR COMPLETE SNOW CHANGEOVER THROUGH MOST OF THE DAY. I TIED RAIN/SNOW MIX TO HOURLY TEMPS FOR SIMPLICITY SAKE...BUT WE WILL PROBABLY NEED TO FINE TUNE THIS AS WE GET A BETTER HANDLE ON DAYTIME TEMPS AND AXIS OF PRECIP. THIS CHANGE OVER ALSO IMPACTS SNOW AMOUNTS...WITH ALL SNOW POSSIBLY PUTTING US WITHIN ADVISORY CRITERIA NORTH OF I-70 (3-5"). CURRENT FORECAST IS CONSIDERABLY LESS SINCE IT IS FAVORING MORE OF A MIX/LIQUID EVENT...JUST ANOTHER THING WE WILL NEED TO FINE TUNE. FRIDAY-SUNDAY...SHORTWAVE RIDGING WILL BE FOLLOWED BY A TRANSITION TO SPLIT FLOW...SHIFTING THE NORTHERN STORM TRACK WELL NORTH AND EAST. THIS WILL SUPPORT DRY CONDITIONS FRI/FRI NIGHT. WE SHOULD ALSO SEE A RETURN OF SEASONAL TO ABOVE NORMAL TEMPS BY NEXT WEEKEND. THE MAIN DIFFERENCE BETWEEN MODELS IS ON SATURDAY-SUNDAY WHEN ECMWF SHOWS A STRONGER TROUGH DEVELOPING ALONG THE SOUTHERN STORM TRACK AND MOVES THIS TROUGH FURTHER NORTH TOWARDS KS. GFS IS WEAKER AND FAVORS SUNDAY FOR PRECIP CHANCES. I KEPT SLIGHT CHANCE POPS IN PLACE DURING THESE PERIODS...HOWEVER CONFIDENCE IS NOT PARTICULARLY HIGH CONSIDERING THE LACK OF CONSISTENCY AND RANGE. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 1107 AM MDT MON MAR 31 2014 SOME MVFR CIG AND VISIBILITY RESTRICTIONS WILL CONTINUE THIS AFTERNOON AT KMCK DUE TO BLOWING DUST NEARBY. GUSTY NORTHWEST WIND WILL GRADUALLY DECREASE AFTER SUNSET THIS EVENING AT KGLD AND KMCK AS HIGH PRESSURE MOVES INTO THE CENTRAL PLAINS. WIND WILL SHIFT TO THE SOUTHEAST TUESDAY MORNING AS THE HIGH SHIFTS EAST. CONDITIONS WILL BE VFR AT KGLD AND KMCK THROUGH THE 24 HOUR PERIOD. && .FIRE WEATHER... ISSUED AT 300 AM MDT MON MAR 31 2014 TODAY...WILL NEED TO MONITOR LOCATIONS ALONG AND SOUTH OF HIGHWAY 40 AND ESPECIALLY SOUTH OF HIGHWAY 96 FOR RELATIVE HUMIDITY VALUES APPROACHING 15 PERCENT. RIGHT NOW AM JUST ABOVE THAT THRESHOLD NEEDED FOR FIRE WEATHER HIGHLITE. WINDS IN THIS AREA GENERALLY FROM THE NORTHWEST GUSTING 40 TO PERHAPS 45 MPH. TUESDAY...WILL NEED TO WATCH FAR WEST/SOUTHWEST PORTIONS OF CHEYENNE AND KIT CARSON COUNTIES (GENERALLY WEST OF A LINE FROM FLAGLER TO KIT CARSON) FOR THE POSSIBILITY OF CRITICAL FIRE WEATHER CONDITIONS BEING MET. CURRENTLY HAVE RELATIVE HUMIDITY VALUES DOWN TO 16-17%. THESE LOW VALUES WILL COMBINE WITH SOUTH TO SOUTHEAST WINDS GUSTING 35 TO PERHAPS 40 MPH. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...HIGH WIND WARNING UNTIL 7 PM MDT /8 PM CDT/ THIS EVENING FOR KSZ001-013-014. DUST STORM WARNING UNTIL 8 PM CDT THIS EVENING FOR KSZ002>004- 015-016. WIND ADVISORY UNTIL 7 PM MDT /8 PM CDT/ THIS EVENING FOR KSZ027>029-041-042. CO...HIGH WIND WARNING UNTIL 7 PM MDT THIS EVENING FOR COZ090-091. WIND ADVISORY UNTIL 7 PM MDT THIS EVENING FOR COZ092. NE...HIGH WIND WARNING UNTIL 7 PM MDT THIS EVENING FOR NEZ079. DUST STORM WARNING UNTIL 8 PM CDT THIS EVENING FOR NEZ080-081. && $$ UPDATE...JTL SHORT TERM...99 LONG TERM...DR AVIATION...FS FIRE WEATHER...99
AREA FORECAST DISCUSSION
NWS GRAY ME
108 PM EDT MON MAR 31 2014 .SYNOPSIS... LOW PRESSURE WILL MEANDER OFFSHORE TODAY...BEFORE FINALLY PULLING AWAY TONIGHT. HIGH PRESSURE WILL NUDGE IN BEHIND THE LOW FOR TUESDAY. A WEAK FRONT WILL CROSS THE AREA ON WEDNESDAY. HIGH PRESSURE WILL KEEP THINGS DRY THROUGH FRIDAY. LOW PRESSURE WILL TRACK INTO ONTARIO AND QUEBEC NEXT WEEKEND...SPREADING PRECIPITATION ACROSS MAINE AND NEW HAMPSHIRE. && .NEAR TERM /TONIGHT/... 1PM UPDATE... BAND OF PRECIPITATION HAS FINALLY SHIFTED OFFSHORE. ANOTHER AREA OF PRECIPITATION IS BLOSSOMING JUST OFF THE COAST AND MOVING INTO EASTERN MAINE. THIS MAY AFFECT THE MIDCOAST AREA THIS AFTERNOON. OTHERWISE THE PRECIPITATION IS DONE FOR OUR AREA. 10AM UPDATE... BAND OF PRECIPITATION HAS WEAKENED A BIT AND SHIFTED SLIGHTLY EASTWARD. HAVE REMOVED THE WINTER WEATHER ADVISORIES FOR AREAS BEHIND THE BAND. ADDITIONAL LIGHT ICE AND SLEET ACCUMULATIONS ARE POSSIBLE IN THE REMAINING ADVISORY AREA. WILL CONTINUE TO SEE A TRANSITION FROM FREEZING RAIN TO SLEET THEN TO SNOW BEFORE PRECIPITATION ENDS AROUND NOON. 830AM UPDATE... NARROW BAND OF PRIMARILY SLEET / FREEZING RAIN / RAIN CONTINUES TO PERSIST OVER ROUGHLY THE SAME AREA JUST INLAND OF THE COAST THIS MORNING. SOME SNOW WAS NOTED ON THE NORTHERN END OF THE BAND AT WISCASSET AND AUGUSTA. TEMPERATURE PROFILE ALOFT NOTED ON THE GYX SOUNDING THIS MORNING SHOWS A WELL PRONOUNCED SLEET SOUNDING WITH A LARGE INVERSION TO +6 C AT AROUND 800 MB WITH A STEEP COOLING TO AROUND -6 C AT 900 MB. AS THE DAY GOES ON... EXPECT THE WARMER AIR ALOFT TO SHIFT EAST... SO THE PRECIPITATION WILL CHANGE TO SLEET AND SNOW WITH LESS FREEZING RAIN. SURFACE TEMPERATURES WILL BE NEAR OR JUST ABOVE FREEZING SO THE TOTAL ACCUMULATION WILL LIKELY REMAIN NEAR OR BELOW ONE INCH. 7AM UPDATE... HAVE UPDATE THE GRIDS TO HIT THE FREEZING RAIN AND SLEET HARD ACROSS SOUTHERN INTERIOR PORTIONS OF THE FORECAST AREA AS DRIVING CONTINUES TO BECOME MORE AND MORE TREACHEROUS. ICE ACCRETION WILL BE A QUARTER TO NEARLY A HALF INCH IN THIS REGION. HAVE ALSO UPDATED TO REMOVE WINTER WEATHER ADVISORIES AND FLOOD WATCHES IN AREAS WHERE THE PRECIPITATION HAS COME TO AN END. ORIGINAL DISCUSSION... BANDS OF RAIN AND MIXED PRECIPITATION CONTINUE TO ROTATE BACK INTO THE FORECAST AREA FROM THE GULF OF MAINE EARLY THIS MORNING. THIS WILL ALLOW FOR UP TO A QUICK INCH OF ADDITIONAL RAINFALL ON TOP OF THE HEAVY RAINS THAT FELL OVER SOUTHERN LOCATIONS YESTERDAY. LATEST HRRR RUN DEPICTS THIS PRECIPITATION ASSOCIATED WITH THE UPPER LEVEL TROUGH VERY WELL. MUCH OF THE RAINFALL/MIX WILL BE DISSIPATING AROUND 16Z. AREAS OF SLEET AND FREEZING RAIN CONTINUE OVER CENTRAL LOCATIONS...HOWEVER IT HAS BEEN LIGHT. FOR NOW...WILL CONTINUE WITH THE WINTER WEATHER ADVISORIES THIS PACKAGE. WITH PLENTY OF CLOUD COVER AND STRONG...GUSTY NORTHERLY WINDS...WE DO NOT EXPECT THE TEMPERATURES TO RECOVER SIGNIFICANTLY TODAY. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/... STUBBORN SURFACE AND UPPER LEVEL LOW SLOWLY MOVE OUT TO SEA TONIGHT...ALLOWING FOR CLEARING TO FINALLY TAKE PLACE. SUNSHINE WILL MAKE AN APPEARANCE BACK TO OUR FORECAST AREA ON TUESDAY...WITH MODERATING TEMPERATURES AND MUCH LESS IN THE WAY OF GUSTY WINDS. && .LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/... MODELS ARE IN GENERAL AGREEMENT ON BROAD WESTERLY OR WEST- SOUTHWEST FLOW THIS PERIOD...THAT KEEPS ARCTIC AIR BOTTLED UP WELL TO OUR NORTH AND RESULTS IN NEAR NORMAL TEMPERATURES FOR THE PERIOD. DIFFERENCES EMERGE AFTER THURSDAY WITH TIMING OF INDIVIDUAL SHORTWAVES ADDING UNCERTAINTY TO THE FORECAST. IN THE DAILIES...A COLD FRONT WILL CROSS THE AREA WEDNESDAY FOLLOWED BY HIGH PRESSURE AND DRY AIR FOR THURSDAY AND FRIDAY. LOW PRESSURE APPROACHES FROM THE GREAT LAKES FOR SATURDAY AND SUNDAY. && .AVIATION /17Z MONDAY THROUGH FRIDAY/... SHORT TERM...ONE LAST ROUND OF LOCALLY IFR CONDITIONS AND RAIN/SNOW/SLEET WILL CONTINUE INTO THIS MORNING WITH IMPROVING CONDITIONS LATER IN THE DAY. WINDS WILL BE GUSTY OUT OF THE NORTH. LONG TERM... WED...SCT MVFR IN RAIN OR SNOW SHOWERS. SAT - SUN...AREAS OF MVFR IN RAIN AND SNOW WITH LOCAL IFR POSSIBLE. && .MARINE... SHORT TERM...NORTHERLY GALES EXPECTED RIGHT THROUGH TONIGHT AS LOW PRESSURE IS SLOW TO PULL AWAY. LONG TERM... THU...SMALL CRAFT WINDS AND SEAS ARE LIKELY. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...NONE. NH...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL NOON EDT TUESDAY FOR ANZ151-153. GALE WARNING UNTIL NOON EDT TUESDAY FOR ANZ150-152-154. && $$ SYNOPSIS... NEAR TERM... SHORT TERM... LONG TERM... AVIATION... MARINE...
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
405 PM CDT Mon Mar 31 2014 .SHORT TERM...(This Evening through Tuesday) Issued at 401 PM CDT MON MAR 31 2014 A pretty potent surface low resides just north of the forecast area in southern Minnesota, however the pressure gradient associated with that low remains strong over the forecast area, producing strong southwest winds. Good mixing through the day and a dry southwesterly component has caused RH values to drop to around 30 percent, with some very localized areas dropping to the lower 20 percent range, especially in far western Missouri. Surface observations indicate that a cold front currently sits across far NW Missouri. This cold front will continue to push S/SE through the area over the next several hours, causing winds to switch from the southwest to the west/northwest overnight. While the initial winds behind the front will be somewhat gusty, expect a general decline in winds through the overnight hours. HRRR has been somewhat consistent in producing some signals for isolated to scattered convection along the cold front in the 23z to 03z time frame across C Missouri, but given the weak signal and forecast soundings showing a struggle to get saturation, will only go out with low end chance PoPs for C Missouri in the evening time frame. Should a thunderstorm get going along the front the dry low levels of the atmosphere bring about a sort of inverted-V sounding. While the overall potential is very low, there could be an outside chance at a damaging wind gust or two if any storm gets healthy along the front. Once the cold front clears the area expect the chances for precipitation to trend toward no chance. .LONG TERM...(Tuesday Night through Monday) Issued at 401 PM CDT MON MAR 31 2014 On Tuesday evening, a deepening trough across the western CONUS and southerly low-level flow off the Gulf will allow for wetter weather through the remainder of the work week. A slow-moving warm front will lift into the area and stall somewhere around the vicinity of I-70, resulting in several rounds of thunderstorms, some possibly strong to severe, for Tuesday night through Thursday. A few isolated thunderstorms should begin to develop on Tuesday evening as the low-level jet begins to increase and the frontal boundary begins to edge into the region. The most widespread convection is expected after 06z, and should be elevated in nature. Hail is possible with any robust elevated storms that develop, but widespread severe weather is not anticipated. The main challenge for severe potential Wednesday will be the presence and influence of morning convection across the region. Without any real feature to sweep out nighttime convection, rain showers and cloud cover may prevent strong instability from developing. Shear profiles, particularly along the warm front, will be very supportive of severe weather, and any storms that develop will have the potential to be severe. Right now the area near the warm front looks like it could remain very capped, but any clearing will likely result in explosive storm development, especially along and south of I-70. Model differences increase on Thursday night into Friday with the position of the surface low and associated front, which will strongly impact severe weather chances. For now, have trended the higher PoPs towards the southeastern corner of the CWA, but will need to adjust as models come better into focus. Morning convection could again impact instability, but with the strong front sweeping through, storms are likely along and ahead of the boundary during the afternoon and early evening hours. Slightly cooler conditions and quieter weather is expected for the weekend and into early next week. A few showers are possible for Sunday night into Monday, but significant precipitation is not expected. && .AVIATION...(For the 18Z TAFS through 18Z Tuesday Afternoon) Issued at 1244 PM CDT MON MAR 31 2014 Gusty southwest winds will continue through the rest of the day time hours. A cold front with a wind shift to the west then northwest will move through later this evening. Best potential for evening thunderstorms will be east of the terminals tonight, so expect no impact from late afternoon/evening convection. && .FIRE WEATHER... ISSUED AT 412 AM CDT MON MAR 31 2014 Strong southwesterly winds continue across the entire area, however portions of NW Missouri may see a gradual change from southwesterly winds to more of a westerly then northwesterly direction this evening. This wind shift will work its way southeastward through the evening hours. A few scattered showers may pop up along the cold front later this evening, but expect showery activity to be rather sparse and localize. If convective activity affects areas with active fires they could produce some erratic wind behavior. Some lightning may occur with these showers, so fire personnel will need to be aware of possible lightning with any storm that forms this evening. && .EAX WATCHES/WARNINGS/ADVISORIES... KS...RED FLAG WARNING until 7 PM CDT this evening FOR KSZ025-057-060- 102>105. WIND ADVISORY until 7 PM CDT this evening FOR KSZ025-057-060- 102>105. MO...RED FLAG WARNING until 7 PM CDT this evening FOR MOZ001>005- 011>013-020-021-028-029-037. WIND ADVISORY until 7 PM CDT this evening FOR MOZ001>005-011>014- 020>022-028>030-037-043. && $$ SHORT TERM...Leighton LONG TERM...Laflin AVIATION...Leighton FIRE WEATHER...Leighton
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1253 PM CDT MON MAR 31 2014 .UPDATE... ISSUED AT 1253 PM CDT MON MAR 31 2014 STARTING TO GET CLOUD TO GROUND LIGHTNING FROM VALLEY CITY TO THIEF RIVER FALLS...OR IN OTHER WORDS THUNDERSNOW (SEE LATEST SWOMCD FROM SPC FOR MESOSCALE DETAILS). THIS FITS IN WITH WHAT WE WERE EXPECTING AND HAS BEEN ACCOUNTED FOR IN OUR FORECAST. THIS THUNDERSNOW IS WHAT WILL ACCOUNT FOR THE LOCALIZED 20 INCHES THAT SOME AREAS COULD RECEIVE. DID INCREASE SNOWFALL INTO THE 10-12 INCH RANGE FOR VALLEY CITY AND NORTHWARD DUE TO THE OBSERVED LIGHTNING. THE NORTHWEST EDGE OF THE SNOWBAND IS DRYING ON RADAR...AND DECREASED SNOW AMOUNTS FOR THIS AREA. ATTEMPTED TO DEPICT THE SHARP CUT-OFF IN THE FORECAST...BUT THAT IS DIFFICULT. LATEST (15Z) HRRR GUIDANCE INDICATES AN AREA OF DYING CONVECTION MOVING INTO THE FERGUS FALLS...WADENA...PARK RAPIDS...AND POSSIBLY THE BEMIDJI AREA. THE CONCERN HERE CONTINUES TO BE THAT COLD (BELOW FREEZING) SURFACE AIR WILL UNDERCUT THIS RAINFALL...LEADING TO MORE SIGNIFICANT FREEZING RAIN. MAINTAINED THE IDEA OF UP TO 0.20 INCHES OF ICE ACCUMULATION IN THE CURRENT ADVISORY AREA...AND WILL ATTEMPT TO FIGURE OUT DETAILS FOR THIS SITUATION IN THE NEXT FEW HOURS. WINDS SHOULD ONLY INCREASE THIS AFTERNOON...AND THE EXTREME BLIZZARD WORDING IN THE HEADLINES APPEARS RELEVANT. UPDATE ISSUED AT 1123 AM CDT MON MAR 31 2014 SORRY FOR THE LATE DISCUSSION TODAY. FOR THE MOST PART...THIS EVENT IS UNFOLDING AS EXPECTED. THE HEAVY SNOW BAND HAS SET UP ACROSS NORTHEAST NORTH DAKOTA INTO NORTHWESTERN MINNESOTA. ANTICIPATE THAT THIS HEAVY BAND OF SNOW WILL REMAIN STATIONARY FOR A PERIOD OF TIME...AND THEN SLOWLY TRANSITION EASTWARD AS THE LOW PRESSURE BEGINS TO PROPAGATE EASTWARD (INTO THE AFTERNOON THE SFC LOW WILL APPROACH THE REGION PROPAGATING NORTH/NORTHEAST). THE HEAVIEST SNOW IS EXPECTED ACROSS THIS AREA WHERE THE BAND WILL BE NEARLY STATIONARY INTO THE AFTERNOON HOURS. STILL THINKING 10-15 INCHES WITH LOCALIZED AMOUNTS UP TO 20 INCHES. LIGHTER AMOUNTS EXPECTED TO THE SOUTH (AND THE EXTREME NORTHWEST FA WHERE DRY AIR ADVECTING FROM THE NORTH IS CAUSING A SHARP CUT OFF IN SNOW AMOUNTS). THIS IS ALL IN LINE WITH PREVIOUS THINKING...SO ONLY MINOR ADJUSTMENTS WHERE NEEDED. SEE OUR LSR REPORTS FOR THE LATEST SNOWFALL AMOUNTS. WINDS ARE UNFOLDING AS FORECASTED...AND VSBY IS LESS THAN ONE QUARTER MILE WHERE THERE IS FALLING SNOW. IT IS A BLIZZARD. THERE WAS A PERIOD OF FREEZING RAIN ACROSS EXTREME SOUTHEAST NORTH DAKOTA THIS MORNING...WITH AROUND 0.10 INCH ICE REPORTED. THERE WILL LIKELY BE A PERIOD OF DRY CONDITIONS ACROSS THE SOUTHERN VALLEY INTO WEST CENTRAL MINNESOTA INTO THE AFTERNOON HOURS...BUT AS WE APPROACH THE EVENING HOURS (AND THE SFC LOW/FORCING APPROACHES) EXPECT PRECIP (POSSIBLY DYING THUNDERSTORMS FROM THE SOUTH) TO MOVE INTO THIS AREA. MOST MODELS INDICATE THAT THIS WOULD FALL AS RAIN...BUT WITH SFC TEMPS BELOW FREEZING (ALTHOUGH THESE TWO FACTORS STILL A BIT UNCERTAIN). THUS...DID INCREASE THE POSSIBILITY FOR FREEZING RAIN HERE THIS EVENING...WITH ACCUMULATION UP TO 0.20 INCHES. && .SHORT TERM...(TODAY THROUGH TUESDAY) ISSUED AT 412 AM CDT MON MAR 31 2014 CHALLENGES ABOUND WITH WINTER STORM TODAY AND TONIGHT...INCLUDING BUT NOT LIMITED TO PRECIP LOCATION/PHASE/AMOUNTS AND ASSOCIATED HEADLINES. GLOBAL MODELS APPEAR TO HAVE FINALLY LOCKED ONTO AN AGREEABLE SOLUTION...BUT WILL LEAN HEAVILY ON LATEST RAP/HRRR FOR THE FIRST 6 TO 12 HOURS. SFC LOW AT 08 UTC ACROSS CENTRAL NE WILL MOVE OVER SIOUX FALLS SD BY 18 UTC AND THEN TOWARD THE TWIN CITIES BY 00 UTC. INITIAL DEFORMATION SNOW BAND EARLY THIS MORNING HAS SET UP ALONG A LINE FROM DICKINSON TO HARVEY TO GRAFTON. RAP/HRRR KEEP THIS PRECIP NEARLY STATIONARY THROUGH THE MORNING WITH DRY CONDITIONS TO THE SOUTH. AS THE SFC LOW MOVES EAST AND MID-LEVEL FRONTOGENESIS STRENGTHENS...PRECIP DEVELOPMENT BECOMES MORE ROBUST ACROSS A WIDER SWATH OF THE FORECAST AREA WITH THE HEAVIEST SNOW BAND BY MID-AFTERNOON ALONG A LINE FROM VALLEY CITY TO GRAND FORKS TO WARROAD. IN ADDITION...ANY PRECIP THIS MORNING ACROSS THE SOUTH WILL LIKELY BE RAIN OR RAIN/FREEZING RAIN MIX GIVEN 850 HPA TEMPERATURES ABOVE 0 C. MODEL SOUNDINGS SUGGEST PRECIP WILL CHANGE OVER TO SNOW IN FARGO AROUND THE NOON HOUR AND NOT UNTIL LATE AFTERNOON ACROSS WEST CENTRAL MN. FINE-TUNED SNOW AMOUNTS BASED ON THIS THINKING WITH THE HEAVIEST BAND OF 10 INCHES OR MORE FROM NEW ROCKFORD TO GRAFTON TO WARROAD. FARTHER SOUTH FROM VALLEY CITY TO ADA TO BEMIDJI EXPECT 6 TO 10 INCHES AND ONLY 3 TO 6 INCHES ACROSS SOUTHEAST ND INTO WEST CENTRAL MN. SNOW AMOUNTS MAY BE HIGHLY VARIABLE OVER SHORT DISTANCES GIVEN THE NATURE OF THIS WINTER STORM. WINDS AT 08 UTC ACROSS EASTERN ND ALREADY SUSTAINED FROM 20 TO 30 MPH WITH HIGHER GUSTS. 925 HPA WINDS INCREASE LATER THIS MORNING FROM 40 TO 50 KTS AND CONTINUE THROUGH THE AFTERNOON AND EVENING. EXPECT WIDESPREAD BLIZZARD CONDITIONS TO DEVELOP ONCE MODERATE TO HEAVY SNOW BEGINS TO FALL ALONG AND WEST OF THE VALLEY. WHETHER AN AREA RECEIVES 2 INCHES OR 12 INCHES OF SNOW... WINDS WILL BE STRONG ENOUGH TO CAUSE SIGNIFICANT BLOWING AND DRIFTING WITH VISIBILITIES BELOW 1/4 MILE. TRAVEL WILL BECOME EXTREMELY HAZARDOUS BY THIS AFTERNOON...LIKELY RESULTING IN NUMEROUS ROAD CLOSURES. ALTHOUGH CURRENT START-TIMES ON HEADLINES MAY BE 3 TO 6 HOURS EARLY DEPENDING ON THE PART OF THE COUNTY (NORTHWEST VS SOUTHEAST)... DID NOT MAKE ANY CHANGES EXCEPT TO UPGRADE BLIZZARD WATCHES ACROSS THE SOUTH TO BLIZZARD WARNINGS. ALTHOUGH SNOW AMOUNTS WILL BE LESS... BLIZZARD CONDITIONS TO DEVELOP ACROSS SOUTHEAST ND INTO THE FAR SOUTHERN VALLEY AFTER 18 UTC AND AFTER 00 UTC ACROSS WEST CENTRAL MN. ALL HEADLINES EXPIRE AT 12 UTC TUESDAY. CONDITIONS TO GRADUALLY IMPROVE ON TUESDAY...ALTHOUGH IT WILL BE VERY COLD FOR APRIL FOOLS DAY WITH HIGH TEMPERATURES ONLY IN THE 20S. BREEZY NORTHWEST WIND MAY RESULT IN ADDITIONAL BLOWING AND DRIFTING OF THE FRESH SNOW. .LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY) ISSUED AT 412 AM CDT MON MAR 31 2014 WEDNESDAY WILL BE DRY AND MOSTLY SUNNY AS HIGH PRESSURE BUILDS ACROSS THE NORTHERN PLAINS. TEMPERATURES WILL WARM SLIGHTLY WITH AFTERNOON HIGHS IN THE UPPER 20S TO MID 30S. FOR THURSDAY THROUGH SUNDAY...THE MAIN FCST CHALLENGE WILL BE NEXT WEATHER SYSTEM TO IMPACT THE PLAINS AND THE UPPER MIDWEST THU-FRI PERIOD. THIS SYSTEM LOOKS TO BE QUITE A BIT FARTHER SOUTH AND EAST BUT STILL CLOSE ENOUGH TO BRING LIGHT SNOWS TO FAR SE ND/WCNTRL MN ESP IF ECMWF MODEL IS CORRECT. IT HAS HELD ONTO A BIT FARTHER NORTHWEST TRACK THE PAST FEW DAYS COMPARED TO THE GFS. AT THE PRESENT BASED ON ECMWF GREAT HANDLING OF THE CURRENT SYSTEM WILL FAVOR IT AND THAT IS WHAT THE ALL BLEND POPS DO IT APPEARS. AFTER THIS PASSES A BIT WARMER AIR MOVES IN FOR THE WEEKEND WITH HIGHS IN THE 40S. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 1253 PM CDT MON MAR 31 2014 STEADIEST SNOW SO FAR HAS MAINLY BEEN CONFINED TO KDVL AND KGFK. AS THE AFTERNOON GOES ON EXPECT IT TO PICK UP AT KTVF/KFAR BUT WILL LIKELY TAKE THE LONGEST AT KBJI. SEEMS LIKE ONCE THE SNOW MOVES IN VSBYS QUICKLY DETERIORATE AS WINDS ARE ALREADY QUITE STRONG. WILL GO AHEAD AND LEAVE THE WORST CONDITIONS THRU MOST OF THE NIGHT WITH SOME IMPROVEMENT LATE AT KDVL AND THEN BY MID MORNING IN THE RED RIVER VALLEY. NOT SURE HOW FAST VSBYS WILL IMPROVE IN THE MORNING SINCE WINDS WILL STILL BE BLOWING BUT GENERALLY THEY SHOULD SLOWLY IMPROVE FROM WEST TO EAST. ONCE THE SNOW STOPS FALLING AND CLOUDS DEPART VSBYS ARE BOUND TO IMPROVE. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...BLIZZARD WARNING UNTIL 7 AM CDT TUESDAY FOR NDZ052-053. BLIZZARD WARNING UNTIL 7 AM CDT TUESDAY FOR NDZ006>008-014>016- 024-026>030-038-039-049-054. MN...BLIZZARD WARNING UNTIL 7 AM CDT TUESDAY FOR MNZ029. WINTER STORM WARNING UNTIL 7 AM CDT TUESDAY FOR MNZ005-006-008- 009-013>017-022>024-027-028. BLIZZARD WARNING FROM 7 PM THIS EVENING TO 7 AM CDT TUESDAY FOR MNZ030-040. BLIZZARD WARNING UNTIL 7 AM CDT TUESDAY FOR MNZ001>004-007. WINTER WEATHER ADVISORY FROM 7 PM THIS EVENING TO 7 AM CDT TUESDAY FOR MNZ031-032. && $$ UPDATE...TG SHORT TERM...ROGERS LONG TERM...ROGERS/RIDDLE AVIATION...GODON
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
1224 PM CDT MON MAR 31 2014 .UPDATE... ISSUED AT 1108 AM CDT MON MAR 31 2014 MUCH OF THE CWA IN THE DRY SLOT AT THIS TIME...WITH SUNNY SKIES AND BLUSTERY WINDS. DID GO AHEAD AND WARM HIGH TEMPERATURES UP SEVERAL DEGREES IN THE DRY SLOT...WITH 60S AND 70S LIKELY. COLD FRONT WILL THEN MOVE THROUGH FROM WEST TO EAST WITH CRASHING TEMPERATURES THIS AFTERNOON. BASED ON LATEST GUIDANCE...EXPECTING ANY SHOWER AND THUNDERSTORM DEVELOPMENT WITH THE COLD FRONT TO STAY EAST OF OUR CWA. BEGINNING TO SEE ELEVATED CONVECTION GO ON THE EDGE OF THE DRY SLOT ACROSS SOUTH CENTRAL SOUTH DAKOTA. AS MOISTURE INCREASES AND BECOMES DEEPER IN THIS AREA...A BIT WORRIED THIS COULD BECOME THE DOMINANT BAND OF SNOW...WITH A DECENT AMOUNT OF ELEVATED INSTABILITY PRESENT. LATEST NAM....HRRR AND RAP ARE IN FACT HINTING AT THIS. SO WILL NEED TO KEEP A CLOSE EYE ON THINGS. MAY NEED TO EVENTUALLY BUMP SNOWFALL TOTALS UP OVER PORTIONS OF THE BLIZZARD WARNING...AND WILL HAVE TO WATCH HOW FAR SOUTH THIS SECOND AREA OF SNOW MAKES IT. WITH THE VERY STRONG WINDS...IT WILL NOT TAKE MUCH TO CREATE ISSUES. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 457 AM CDT MON MAR 31 2014 AT THIS TIME...STRONG SURFACE LOW PRESSURE IS LOCATED IN NORTH CENTRAL NEBRASKA. FINALLY THE MODELS HAVE COME AROUND TO BETTER AGREEMENT IN HOW THEY TRACK THE SURFACE LOW NORTHEASTWARD ACROSS THE FORECAST AREA TODAY. THAT SAID...THERE ARE STILL SOME DISCREPANCIES IN THE TEMPERATURES OFF THE SURFACE WHICH ARE KEY TO PRECIPITATION TYPE OF COURSE. STILL PREFERRED A BLEND OF THE ECMWF AND GEM FOR BOTH THE SURFACE LOW TRACK AND TEMPERATURES ALOFT. DYNAMICALLY...THE MODELS CONTINUE TO SHOW THE MAIN PORTION OF THE UPPER WAVE LIFTING WELL TO THE NORTH OF OUR FORECAST AREA TODAY. THE SURFACE LOW FOLLOWS SUIT...AND WILL LIKELY TAKE A TRACK FROM GREGORY COUNTY SD...TO NEAR MARSHALL MN TODAY. THIS WILL PRODUCE A DRY SLOT FOR MANY OF OUR EASTERN ZONES FOR A GOOD CHUNK OF TODAY. CURRENTLY HOWEVER...A FEW SHOWERS AND ISOLATED THUNDERSTORMS ARE HEADING INTO NORTHWEST IA ALONG THE TONGUE OF WARM AIR ADVECTION AND POSITIVE THETA E ADVECTION...AND WILL LIKELY EXIT OUR SOUTHEAST ZONES BEFORE MID MORNING ALLOWING FOR A POTENTIAL FOR A SECOND ROUND OF REDEVELOPMENT. THE PV SURGE ON THE 1.5 SURFACE REVEALS DEEPENING TO AROUND 500MB IN NORTHWEST IA THIS AFTERNOON WHICH IS PRETTY STRONG. WEAK ELEVATED INSTABILITY IS PERSISTENT AHEAD OF THE WIND SHIFT TODAY...THEN GETS CUTOFF FIRST IN OUR SOUTHERN ZONES AS THE STRONG PV SURGE MOVES EASTWARD...AND THE SURFACE FRONT GETS OCCLUDED. SO BY AFTERNOON...THE ONLY REMAINING ISOLATED THUNDER CHANCES WILL BE IN SOUTHWEST MN AS NORTHWEST IA GETS UNDERCUT WITH STABILIZED AIR. TEMPERATURES WILL BE VERY WARM FOR A WHILE TODAY IN OUR EAST... RAPIDLY COOLING HEADING WESTWARD. DID NOT NEED TO ALTER HIGHS MUCH FROM THE LAST FORECAST...WITH HIGH TEMPERATURES POSSIBLY VARYING UP TO AS MUCH AS 30 DEGREES FROM CHAMBERLAIN TO SIOUX CITY AND STORM LAKE. CONCERNING THE WINTER WEATHER...OPTED TO TAKE THE ZONES WHICH WERE IN THE BLIZZARD WATCH AND PLACED THEM IN A BLIZZARD WARNING. GENERALLY SPEAKING...NOT A TON OF SNOW IS EXPECTED...RANGING IN THE WARNING AREA OF ABOUT 2 TO 4 INCHES. THAT SAID...WE NEED TO WATCH OUR ZONES IN EAST CENTRAL SD...ESPECIALLY FROM HURON TO KINGSBURY COUNTY FOR LOCALLY HEAVIER AMOUNTS. THINGS MAY COME TOGETHER IN EAST CENTRAL SD FOR A TIME THIS AFTERNOON AND EARLY EVENING...WHEN TROWALING AT THE 300 TO 305K LAYER IS STRONG COUPLED WITH VERY ABUNDANT MID LEVEL INSTABILITY. MID LEVEL INSTABILITY IS ABUNDANT EVERYWHERE...BUT OUR FAR WESTERN AND FAR NORTHERN ZONES IS WHERE THIS INSTABILITY CAN TAP INTO THE DEEPEST MOISTURE PROFILE. SO ADMITTEDLY THIS IS BOTHERSOME...AND HELPED TO DECIDE WHETHER TO GO BLIZZARD WARNING IN THOSE AREAS AS OPPOSED TO AN ADVISORY. FURTHERMORE...SOUNDINGS SHOW A DENDRITIC PROFILE GENERALLY FROM NEAR CHAMBERLAIN TO DE SMET SD...WHICH COULD PRODUCE BIG SNOW FLAKES FOR ABOUT A 3 OR 4 HOUR WINDOW. SO SOMETHING FOR THE DAY CREW TO WATCH FOR CONCERNING SNOW AMOUNTS IN THAT SNOW AMOUNTS IN THE SPRING CAN ALWAYS ACCUMULATE IN A BIG HURRY. ADJACENT TO THE SOUTH OF THE WARNING AREA...WE WILL KEEP OUR ADVISORY GOING AS DEEP MOISTURE BEGINS TO SHUT OFF RAPIDLY. STILL... IT WILL NOT TAKE MUCH SNOW TO INTERFERE WITH TRAVEL WHEN WINDS ARE 30 TO 45 MPH...AND IN SOME LOCATIONS IN OUR WESTERN ZONES...MIXED LAYER WINDS ARE CLOSE TO 50 MPH. TEMPERATURES BOTH AT THE SURFACE AND ALOFT WILL DROP LIKE A ROCK ONCE THE WINDS TURN TO THE WEST AND NORTHWEST...GIVING A RAPID CHANGEOVER FROM ANY LIGHT RAIN OVER TO SNOW. EVENTUALLY...THIS WILL MAKE IT INTO OUR EASTERN ZONES...ESPECIALLY ALONG AND NORTH OF I 90...VERY LATE THIS AFTERNOON AND EARLY EVENING. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 457 AM CDT MON MAR 31 2014 WINDS WILL CONTINUE TO DIE DOWN TUESDAY AS THE STRING SYSTEM MOVES NORTHEAST AWAY FROM THE AREA. CLOUDS WILL MOMENTARILY DECREASE...BUT WITH THE EXIT OF THE CURRENT STORM SO FAR NORTHEAST SO QUICKLY... THE UPPER FLOW BACKS AROUND TO SOUTHWEST ALREADY BY LATE TUESDAY AND WEAK WAVES BRING PATCHES OF MID LEVEL MOISTURE UP INTO THE AREA LATE TUESDAY INTO WEDNESDAY. THERE IS NOT MUCH DYNAMIC SUPPORT FOR PRECIPITATION BUT A THERMAL GRADIENT QUICKLY REFORMS ALOFT JUST SOUTH OF THE AREA. THE THREAT OF A LITTLE LIGHT RAIN AND SNOW SHOULD SLOWLY REDEVELOP OVER THE SOUTHERN PART OF THE AREA FROM THE SOUTHWEST. SURFACE TEMPERATURES WILL BE COOL...THOUGH WITH A LITTLE WARMING WEDNESDAY. DEVELOPING WEST COAST TROUGH IS PRESENTING A STRONG POTENTIAL FOR A MAJOR PRECIPITATION SYSTEM TO AFFECT THE AREA THURSDAY INTO FRIDAY. THE EC AS USUAL ID THE STRONGEST AND IS FAVORED HERE. IT SHOULD HANDLE THE DYNAMICS OF THE THERMAL AND MOISTURE GRADIENTS BETTER THAN THE GFS AND ESPECIALLY THE NAM. ANYWAY...BESIDES THE ANTICIPATED TRACK...WHAT GIVES THIS SYSTEM SO MUCH POTENTIAL IS A HUGE DIFFERENCE IN MOISTURE AT ALL LEVELS STREAMING INTO THE SYSTEM...IN CONTRAST TO THE RELATIVELY DRY INFLOW TO THE CURRENT STORM. THIS WILL PRESENT THE LIKELIHOOD OF WIDESPREAD PRECIPITATION...POSSIBLY MODERATE TO HEAVY...WITH PLENTY OF CONVECTION NEAR AND SOUTH OF THE SYSTEM. THE POTENTIAL FOR MOISTURE INFLOW INTO THE AREA TO BE LIMITED BY CONVECTION TO THE SOUTH IS THERE...BUT DWARFED BY THE HUGE GENERAL MOISTURE INFLOW. THE CURRENT SYSTEM WILL BE MOVING WAY TOO FAR NORTH TO BRING ANY DRYING TO THE SOUTHERN PLAINS...SO THE MOISTURE AVAILABILITY DOWN THERE WILL JUST BE GETTING STEADILY RICHER FOR THE NEXT 3 TO 4 DAYS. MEANWHILE...THE STRONG EC WHICH BRINGS SO MUCH MOISTURE INFLOW AND WARMTH INTO THE SYSTEM ALSO KEEPS IT COLD ENOUGH FOR THE PRECIPITATION TO BE ALL SNOW OVER THE NORTHERN AND WESTERN PART OF THE AREA...AND THE DYNAMIC COOLING ASSOCIATED WITH SUCH A STRONG SYSTEM CAN ADD TO THE POTENTIAL FOR PRECIPITATION TO BE WET SNOW INSTEAD OF RAIN. YES...THIS STORM COULD WIND UP TRACKING EVEN FURTHER NORTH/NORTHWEST THAN THE CURRENT EC SOLUTION AND THIS COULD AFFECT PRECIP TYPE... THOUGH IT SEEMS PRETTY MUCH GUARANTEED THAT IT WILL BE QUITE A BIT FURTHER SOUTHEAST THAN THE CURRENT STORM. THERE IS STILL ENOUGH POTENTIAL FOR HEAVY WET SNOW TO MAKE SURE THAT POTENTIAL IS KNOWN. ALSO..A FURTHER NORTHWEST TRACK IN THIS THURSDAY SYSTEM IS UNLIKELY TO DEVOID ANY PART OF THE AREA OF PRECIPITATION DUE TO THE RICH MOISTURE AND CONVECTIVE POTENTIAL. EVEN WITH THE WEAKER AMERICAN MODEL SOLUTIONS...THE MOISTURE INFLOW IS STILL THERE TO BRING PLENTY OF PRECIPITATION POTENTIAL. WILL BE GOING OF COURSE FOR TEMPERATURES...ESPECIALLY DAYTIME...TO BE COOLER THAN GUIDANCE WITH THIS SYSTEM THROUGH FRIDAY. AT THIS TIME WINDS LOOK TO PEAK MODESTLY STRONG...SO WOULD NOT EMPHASIZE ANY BLIZZARD POTENTIAL AT THIS TIME BUT WOULD NOT RULE IT OUT. FRIDAY SHOULD BE THE DAY THE SYSTEM IS PULLING OUT. THIS WILL LIKELY LEAVE ROOM FOR SOME WARMING OVER THE WEEKEND...THOUGH NOT NEARLY AS STRONG AS WHAT WE HAD WITH THE WEEKEND JUST PAST. ALSO...THERE DOES SEEM TO BE A RISK FOR A FEW SHOWERS BY SUNDAY WITH SOME WEAK UPPER SUPPORT IN A REDEVELOPING WESTERLY FLOW ALOFT. THESE DETAILS COULD CHANGE WITH FUTURE MODEL RUNS...BUT AM NOT LOOKING FOR ANOTHER MAJOR SYSTEM SOON AFTER THE THURSDAY INTO FRIDAY ONE. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 1212 PM CDT MON MAR 31 2014 CONDITIONS ARE EXPECTED TO RAPIDLY DETERIORATE FROM SOUTHWEST TO NORTHEAST THIS AFTERNOON AND EVENING AS A POTENT EARLY SPRING STORM LIFTS ACROSS THE AREA. RAIN AND SLEET WILL TRANSITION TO SNOW QUICKLY AS COLDER AIR WRAPS BEHIND THE LOW. ISOLATED THUNDER WILL ALSO BE POSSIBLE...MAINLY THIS AFTERNOON AND EARLY EVENING. EXPECT MVFR AND IFR CEILINGS AND VISIBILITY AS THE RAIN TURNS TO SNOW. SNOW MAY BE HEAVY AT TIMES....WITH LOCALLY LIFR CEILINGS AND VIS POSSIBLE IN SOUTH CENTRAL SD LATE THIS AFTERNOON INTO THE EVENING AND INTO THE HIGHWAY 14 CORRIDOR THIS EVENING AND OVERNIGHT. THE MAIN AREA OF CONCERN WITH LIFT CONDITIONS IS NORTH AND EAST OF A LINE FROM PICKSTOWN TO MADISON TO MARSHALL. THIS INCLUDES THE KHON TAF. WINDS WILL BE AN ONGOING CONCERN AS WELL WITH 25 TO 35 KT SUSTAINED AND GUSTS TO 50 KT. STRONG SOUTHERLY WINDS AHEAD OF THE LOW WILL SHARPLY TURN NORTHWEST ON THE BACK SIDE...WHERE THE STRONGEST WINDS ARE EXPECTED TO OCCUR. LOOK FOR WINDS TO DECREASE FROM WEST TO EAST LATE TONIGHT...AVERAGING AROUND 10 KT BY THE END OF THE TAF PERIOD. && .FIRE WEATHER... ISSUED AT 457 AM CDT MON MAR 31 2014 THE GRASSLAND FIRE DANGER INDEX WILL REACH THE VERY HIGH CATEGORY THIS AFTERNOON IN NORTHWEST IOWA AHEAD OF STRONG LOW PRESSURE. WINDS WILL GENERALLY PREVAIL FROM THE SOUTHWEST AND WILL BE QUITE STRONG AT 25 TO 40 MPH. BUT AS THE COLD FRONT APPROACHES... TEMPERATURES WILL COOL THIS AFTERNOON AND THUS WILL HELP TO RAISE MINIMUM HUMIDITY LEVELS. AT THIS TIME...MINIMUM HUMIDITY VALUES ARE PROJECTED TO BE ABOUT 30 TO 45 PERCENT. && .FSD WATCHES/WARNINGS/ADVISORIES... SD...WIND ADVISORY UNTIL 7 AM CDT TUESDAY FOR SDZ061-062-066-067. WIND ADVISORY UNTIL 1 AM CDT TUESDAY FOR SDZ065-068>071. WINTER WEATHER ADVISORY UNTIL 1 AM CDT TUESDAY FOR SDZ050-063- 064. BLIZZARD WARNING FROM 7 PM THIS EVENING TO 7 AM CDT TUESDAY FOR SDZ040. WINTER WEATHER ADVISORY FROM 4 PM THIS AFTERNOON TO 1 AM CDT TUESDAY FOR SDZ059-060. BLIZZARD WARNING FROM 4 PM THIS AFTERNOON TO 1 AM CDT TUESDAY FOR SDZ039-054. WINTER WEATHER ADVISORY FROM 7 PM THIS EVENING TO 7 AM CDT TUESDAY FOR SDZ055-056. BLIZZARD WARNING UNTIL 1 AM CDT TUESDAY FOR SDZ038-052-053-057- 058. MN...WIND ADVISORY UNTIL 7 AM CDT TUESDAY FOR MNZ080-081-089-090-098. BLIZZARD WARNING FROM 7 PM THIS EVENING TO 7 AM CDT TUESDAY FOR MNZ071-072. WINTER WEATHER ADVISORY FROM 7 PM THIS EVENING TO 7 AM CDT TUESDAY FOR MNZ097. IA...WIND ADVISORY UNTIL 7 AM CDT TUESDAY FOR IAZ001>003-012>014-021- 022-032. WIND ADVISORY UNTIL 1 AM CDT TUESDAY FOR IAZ020-031. NE...WIND ADVISORY UNTIL 1 AM CDT TUESDAY FOR NEZ013-014. && $$ UPDATE...CHENARD SHORT TERM...MJ LONG TERM...MJ AVIATION... FIRE WEATHER...MJ
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
1122 AM CDT MON MAR 31 2014 .UPDATE... ISSUED AT 1108 AM CDT MON MAR 31 2014 MUCH OF THE CWA IN THE DRY SLOT AT THIS TIME...WITH SUNNY SKIES AND BLUSTERY WINDS. DID GO AHEAD AND WARM HIGH TEMPERATURES UP SEVERAL DEGREES IN THE DRY SLOT...WITH 60S AND 70S LIKELY. COLD FRONT WILL THEN MOVE THROUGH FROM WEST TO EAST WITH CRASHING TEMPERATURES THIS AFTERNOON. BASED ON LATEST GUIDANCE...EXPECTING ANY SHOWER AND THUNDERSTORM DEVELOPMENT WITH THE COLD FRONT TO STAY EAST OF OUR CWA. BEGINNING TO SEE ELEVATED CONVECTION GO ON THE EDGE OF THE DRY SLOT ACROSS SOUTH CENTRAL SOUTH DAKOTA. AS MOISTURE INCREASES AND BECOMES DEEPER IN THIS AREA...A BIT WORRIED THIS COULD BECOME THE DOMINANT BAND OF SNOW...WITH A DECENT AMOUNT OF ELEVATED INSTABILITY PRESENT. LATEST NAM....HRRR AND RAP ARE IN FACT HINTING AT THIS. SO WILL NEED TO KEEP A CLOSE EYE ON THINGS. MAY NEED TO EVENTUALLY BUMP SNOWFALL TOTALS UP OVER PORTIONS OF THE BLIZZARD WARNING...AND WILL HAVE TO WATCH HOW FAR SOUTH THIS SECOND AREA OF SNOW MAKES IT. WITH THE VERY STRONG WINDS...IT WILL NOT TAKE MUCH TO CREATE ISSUES. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 457 AM CDT MON MAR 31 2014 AT THIS TIME...STRONG SURFACE LOW PRESSURE IS LOCATED IN NORTH CENTRAL NEBRASKA. FINALLY THE MODELS HAVE COME AROUND TO BETTER AGREEMENT IN HOW THEY TRACK THE SURFACE LOW NORTHEASTWARD ACROSS THE FORECAST AREA TODAY. THAT SAID...THERE ARE STILL SOME DISCREPANCIES IN THE TEMPERATURES OFF THE SURFACE WHICH ARE KEY TO PRECIPITATION TYPE OF COURSE. STILL PREFERRED A BLEND OF THE ECMWF AND GEM FOR BOTH THE SURFACE LOW TRACK AND TEMPERATURES ALOFT. DYNAMICALLY...THE MODELS CONTINUE TO SHOW THE MAIN PORTION OF THE UPPER WAVE LIFTING WELL TO THE NORTH OF OUR FORECAST AREA TODAY. THE SURFACE LOW FOLLOWS SUIT...AND WILL LIKELY TAKE A TRACK FROM GREGORY COUNTY SD...TO NEAR MARSHALL MN TODAY. THIS WILL PRODUCE A DRY SLOT FOR MANY OF OUR EASTERN ZONES FOR A GOOD CHUNK OF TODAY. CURRENTLY HOWEVER...A FEW SHOWERS AND ISOLATED THUNDERSTORMS ARE HEADING INTO NORTHWEST IA ALONG THE TONGUE OF WARM AIR ADVECTION AND POSITIVE THETA E ADVECTION...AND WILL LIKELY EXIT OUR SOUTHEAST ZONES BEFORE MID MORNING ALLOWING FOR A POTENTIAL FOR A SECOND ROUND OF REDEVELOPMENT. THE PV SURGE ON THE 1.5 SURFACE REVEALS DEEPENING TO AROUND 500MB IN NORTHWEST IA THIS AFTERNOON WHICH IS PRETTY STRONG. WEAK ELEVATED INSTABILITY IS PERSISTENT AHEAD OF THE WIND SHIFT TODAY...THEN GETS CUTOFF FIRST IN OUR SOUTHERN ZONES AS THE STRONG PV SURGE MOVES EASTWARD...AND THE SURFACE FRONT GETS OCCLUDED. SO BY AFTERNOON...THE ONLY REMAINING ISOLATED THUNDER CHANCES WILL BE IN SOUTHWEST MN AS NORTHWEST IA GETS UNDERCUT WITH STABILIZED AIR. TEMPERATURES WILL BE VERY WARM FOR A WHILE TODAY IN OUR EAST... RAPIDLY COOLING HEADING WESTWARD. DID NOT NEED TO ALTER HIGHS MUCH FROM THE LAST FORECAST...WITH HIGH TEMPERATURES POSSIBLY VARYING UP TO AS MUCH AS 30 DEGREES FROM CHAMBERLAIN TO SIOUX CITY AND STORM LAKE. CONCERNING THE WINTER WEATHER...OPTED TO TAKE THE ZONES WHICH WERE IN THE BLIZZARD WATCH AND PLACED THEM IN A BLIZZARD WARNING. GENERALLY SPEAKING...NOT A TON OF SNOW IS EXPECTED...RANGING IN THE WARNING AREA OF ABOUT 2 TO 4 INCHES. THAT SAID...WE NEED TO WATCH OUR ZONES IN EAST CENTRAL SD...ESPECIALLY FROM HURON TO KINGSBURY COUNTY FOR LOCALLY HEAVIER AMOUNTS. THINGS MAY COME TOGETHER IN EAST CENTRAL SD FOR A TIME THIS AFTERNOON AND EARLY EVENING...WHEN TROWALING AT THE 300 TO 305K LAYER IS STRONG COUPLED WITH VERY ABUNDANT MID LEVEL INSTABILITY. MID LEVEL INSTABILITY IS ABUNDANT EVERYWHERE...BUT OUR FAR WESTERN AND FAR NORTHERN ZONES IS WHERE THIS INSTABILITY CAN TAP INTO THE DEEPEST MOISTURE PROFILE. SO ADMITTEDLY THIS IS BOTHERSOME...AND HELPED TO DECIDE WHETHER TO GO BLIZZARD WARNING IN THOSE AREAS AS OPPOSED TO AN ADVISORY. FURTHERMORE...SOUNDINGS SHOW A DENDRITIC PROFILE GENERALLY FROM NEAR CHAMBERLAIN TO DE SMET SD...WHICH COULD PRODUCE BIG SNOW FLAKES FOR ABOUT A 3 OR 4 HOUR WINDOW. SO SOMETHING FOR THE DAY CREW TO WATCH FOR CONCERNING SNOW AMOUNTS IN THAT SNOW AMOUNTS IN THE SPRING CAN ALWAYS ACCUMULATE IN A BIG HURRY. ADJACENT TO THE SOUTH OF THE WARNING AREA...WE WILL KEEP OUR ADVISORY GOING AS DEEP MOISTURE BEGINS TO SHUT OFF RAPIDLY. STILL... IT WILL NOT TAKE MUCH SNOW TO INTERFERE WITH TRAVEL WHEN WINDS ARE 30 TO 45 MPH...AND IN SOME LOCATIONS IN OUR WESTERN ZONES...MIXED LAYER WINDS ARE CLOSE TO 50 MPH. TEMPERATURES BOTH AT THE SURFACE AND ALOFT WILL DROP LIKE A ROCK ONCE THE WINDS TURN TO THE WEST AND NORTHWEST...GIVING A RAPID CHANGEOVER FROM ANY LIGHT RAIN OVER TO SNOW. EVENTUALLY...THIS WILL MAKE IT INTO OUR EASTERN ZONES...ESPECIALLY ALONG AND NORTH OF I 90...VERY LATE THIS AFTERNOON AND EARLY EVENING. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 457 AM CDT MON MAR 31 2014 WINDS WILL CONTINUE TO DIE DOWN TUESDAY AS THE STRING SYSTEM MOVES NORTHEAST AWAY FROM THE AREA. CLOUDS WILL MOMENTARILY DECREASE...BUT WITH THE EXIT OF THE CURRENT STORM SO FAR NORTHEAST SO QUICKLY... THE UPPER FLOW BACKS AROUND TO SOUTHWEST ALREADY BY LATE TUESDAY AND WEAK WAVES BRING PATCHES OF MID LEVEL MOISTURE UP INTO THE AREA LATE TUESDAY INTO WEDNESDAY. THERE IS NOT MUCH DYNAMIC SUPPORT FOR PRECIPITATION BUT A THERMAL GRADIENT QUICKLY REFORMS ALOFT JUST SOUTH OF THE AREA. THE THREAT OF A LITTLE LIGHT RAIN AND SNOW SHOULD SLOWLY REDEVELOP OVER THE SOUTHERN PART OF THE AREA FROM THE SOUTHWEST. SURFACE TEMPERATURES WILL BE COOL...THOUGH WITH A LITTLE WARMING WEDNESDAY. DEVELOPING WEST COAST TROUGH IS PRESENTING A STRONG POTENTIAL FOR A MAJOR PRECIPITATION SYSTEM TO AFFECT THE AREA THURSDAY INTO FRIDAY. THE EC AS USUAL ID THE STRONGEST AND IS FAVORED HERE. IT SHOULD HANDLE THE DYNAMICS OF THE THERMAL AND MOISTURE GRADIENTS BETTER THAN THE GFS AND ESPECIALLY THE NAM. ANYWAY...BESIDES THE ANTICIPATED TRACK...WHAT GIVES THIS SYSTEM SO MUCH POTENTIAL IS A HUGE DIFFERENCE IN MOISTURE AT ALL LEVELS STREAMING INTO THE SYSTEM...IN CONTRAST TO THE RELATIVELY DRY INFLOW TO THE CURRENT STORM. THIS WILL PRESENT THE LIKELIHOOD OF WIDESPREAD PRECIPITATION...POSSIBLY MODERATE TO HEAVY...WITH PLENTY OF CONVECTION NEAR AND SOUTH OF THE SYSTEM. THE POTENTIAL FOR MOISTURE INFLOW INTO THE AREA TO BE LIMITED BY CONVECTION TO THE SOUTH IS THERE...BUT DWARFED BY THE HUGE GENERAL MOISTURE INFLOW. THE CURRENT SYSTEM WILL BE MOVING WAY TOO FAR NORTH TO BRING ANY DRYING TO THE SOUTHERN PLAINS...SO THE MOISTURE AVAILABILITY DOWN THERE WILL JUST BE GETTING STEADILY RICHER FOR THE NEXT 3 TO 4 DAYS. MEANWHILE...THE STRONG EC WHICH BRINGS SO MUCH MOISTURE INFLOW AND WARMTH INTO THE SYSTEM ALSO KEEPS IT COLD ENOUGH FOR THE PRECIPITATION TO BE ALL SNOW OVER THE NORTHERN AND WESTERN PART OF THE AREA...AND THE DYNAMIC COOLING ASSOCIATED WITH SUCH A STRONG SYSTEM CAN ADD TO THE POTENTIAL FOR PRECIPITATION TO BE WET SNOW INSTEAD OF RAIN. YES...THIS STORM COULD WIND UP TRACKING EVEN FURTHER NORTH/NORTHWEST THAN THE CURRENT EC SOLUTION AND THIS COULD AFFECT PRECIP TYPE... THOUGH IT SEEMS PRETTY MUCH GUARANTEED THAT IT WILL BE QUITE A BIT FURTHER SOUTHEAST THAN THE CURRENT STORM. THERE IS STILL ENOUGH POTENTIAL FOR HEAVY WET SNOW TO MAKE SURE THAT POTENTIAL IS KNOWN. ALSO..A FURTHER NORTHWEST TRACK IN THIS THURSDAY SYSTEM IS UNLIKELY TO DEVOID ANY PART OF THE AREA OF PRECIPITATION DUE TO THE RICH MOISTURE AND CONVECTIVE POTENTIAL. EVEN WITH THE WEAKER AMERICAN MODEL SOLUTIONS...THE MOISTURE INFLOW IS STILL THERE TO BRING PLENTY OF PRECIPITATION POTENTIAL. WILL BE GOING OF COURSE FOR TEMPERATURES...ESPECIALLY DAYTIME...TO BE COOLER THAN GUIDANCE WITH THIS SYSTEM THROUGH FRIDAY. AT THIS TIME WINDS LOOK TO PEAK MODESTLY STRONG...SO WOULD NOT EMPHASIZE ANY BLIZZARD POTENTIAL AT THIS TIME BUT WOULD NOT RULE IT OUT. FRIDAY SHOULD BE THE DAY THE SYSTEM IS PULLING OUT. THIS WILL LIKELY LEAVE ROOM FOR SOME WARMING OVER THE WEEKEND...THOUGH NOT NEARLY AS STRONG AS WHAT WE HAD WITH THE WEEKEND JUST PAST. ALSO...THERE DOES SEEM TO BE A RISK FOR A FEW SHOWERS BY SUNDAY WITH SOME WEAK UPPER SUPPORT IN A REDEVELOPING WESTERLY FLOW ALOFT. THESE DETAILS COULD CHANGE WITH FUTURE MODEL RUNS...BUT AM NOT LOOKING FOR ANOTHER MAJOR SYSTEM SOON AFTER THE THURSDAY INTO FRIDAY ONE. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING) ISSUED AT 634 AM CDT MON MAR 31 2014 INITIAL VFR WILL BECOME MVFR CEILINGS 1-3K FEET FROM THE NORTHWEST THROUGH 01/00Z...BY 15Z AT KHON AND BY 23Z AT KSUX. AFTER 19Z VISIBILITIES WILL LOWER TO BELOW 3SM IN SN/BLSN NORTHWEST THIRD OF AREA INCLUDING KHON. AREAS OF 3-5SM IN -RASN THEN LOCAL 1-3SM IN -SN WILL DEVELOP SOUTHEAST TO PKS/FSD/MWM LINE BY 01/00Z. SURFACE GUSTS OF 25 TO 40 KTS FROM THE W/NW WILL DEVELOP FROM THE NORTHWEST BY 01/00Z. GENERAL IMPROVEMENT IN VISIBILITIES THEN CEILING WILL SPREAD FROM WEST TO EAST AFTER 01/03Z. STRONG WINDS WILL BEGIN TO SLOWLY ABATE AFTER 01/06Z. && .FIRE WEATHER... ISSUED AT 457 AM CDT MON MAR 31 2014 THE GRASSLAND FIRE DANGER INDEX WILL REACH THE VERY HIGH CATEGORY THIS AFTERNOON IN NORTHWEST IOWA AHEAD OF STRONG LOW PRESSURE. WINDS WILL GENERALLY PREVAIL FROM THE SOUTHWEST AND WILL BE QUITE STRONG AT 25 TO 40 MPH. BUT AS THE COLD FRONT APPROACHES... TEMPERATURES WILL COOL THIS AFTERNOON AND THUS WILL HELP TO RAISE MINIMUM HUMIDITY LEVELS. AT THIS TIME...MINIMUM HUMIDITY VALUES ARE PROJECTED TO BE ABOUT 30 TO 45 PERCENT. && .FSD WATCHES/WARNINGS/ADVISORIES... SD...WIND ADVISORY UNTIL 7 AM CDT TUESDAY FOR SDZ061-062-066-067. WIND ADVISORY UNTIL 1 AM CDT TUESDAY FOR SDZ065-068>071. WINTER WEATHER ADVISORY UNTIL 1 AM CDT TUESDAY FOR SDZ050-063- 064. BLIZZARD WARNING FROM 7 PM THIS EVENING TO 7 AM CDT TUESDAY FOR SDZ040. WINTER WEATHER ADVISORY FROM 4 PM THIS AFTERNOON TO 1 AM CDT TUESDAY FOR SDZ059-060. BLIZZARD WARNING FROM 4 PM THIS AFTERNOON TO 1 AM CDT TUESDAY FOR SDZ039-054. WINTER WEATHER ADVISORY FROM 7 PM THIS EVENING TO 7 AM CDT TUESDAY FOR SDZ055-056. BLIZZARD WARNING UNTIL 1 AM CDT TUESDAY FOR SDZ038-052-053-057- 058. MN...WIND ADVISORY UNTIL 7 AM CDT TUESDAY FOR MNZ080-081-089-090-098. BLIZZARD WARNING FROM 7 PM THIS EVENING TO 7 AM CDT TUESDAY FOR MNZ071-072. WINTER WEATHER ADVISORY FROM 7 PM THIS EVENING TO 7 AM CDT TUESDAY FOR MNZ097. IA...WIND ADVISORY UNTIL 7 AM CDT TUESDAY FOR IAZ001>003-012>014-021- 022-032. WIND ADVISORY UNTIL 1 AM CDT TUESDAY FOR IAZ020-031. NE...WIND ADVISORY UNTIL 1 AM CDT TUESDAY FOR NEZ013-014. && $$ UPDATE...CHENARD SHORT TERM...MJ LONG TERM...MJ AVIATION... FIRE WEATHER...MJ
FORECAST DISCUSSION FOR ROUTINE AFTERNOON FORECAST ISSUANCE

.SHORT TERM...TONIGHT AND TUESDAY ISSUED AT 250 PM CDT MON MAR 31 2014 LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A STRONG AREA OF LOW PRESSURE LIFTING NORTHEAST NEAR SIOUX FALLS SOUTH DAKOTA. RELATIVELY CLEAN LOOKING DRY SLOT IS PUSHING AHEAD OF THE CYCLONE INTO SW WISCONSIN EARLY THIS AFTERNOON. ON THE LEADING EDGE OF THIS DRY SLOT...SCT TO BKN ARCING LINE SHOWERS IS STRUGGLING TO SURVIVE DUE TO PLENTY OF DRY AIR BELOW 10 KFT. SOME SHOWERS LOOK TO BE REACHING THE GROUND OVER NORTH-CENTRAL WISCONSIN THOUGH. LOOKING FARTHER UPSTREAM...A COLD FRONT IS PROGRESSING EAST ACROSS THE SOUTHERN MISSOURI VALLEY BUT SKIES ARE CLEAR ALONG IT THANKS TO THE DEEP DRY SLOT. BEHIND THE FRONT...WIDESPREAD LOW STRATUS AND SNOW EXIST WITHIN THE COMMA HEAD. PLENTY OF FORECAST CONCERNS THROUGH TOMORROW...INCLUDING POTENTIAL AND TIMING OF PRECIP...AND SNOW ACCUMULATIONS TOMORROW. TONIGHT...NEGATIVELY TILTED SHORTWAVE TROUGH WILL LIFT NORTHEAST ACROSS THE NORTHERN MISSISSIPPI VALLEY TONIGHT AND DRIVE A SURFACE LOW FROM SOUTHWEST MINNESOTA TO WESTERN LAKE SUPERIOR. AHEAD OF THE LOW...700MB FRONT/EDGE OF THE DRY SLOT WILL WORK NE AND PUSH A BKN LINE OF SHOWERS AND SPRINKLES ACROSS THE EASTERN HALF OF THE FORECAST AREA. LATEST NUMERICAL GUIDANCE SUGGESTS THIS LINE WILL REMAIN RELATIVELY TAME THROUGH EARLY THIS EVENING...THEN SUGGEST INTENSIFICATION OVER FAR NE WISCONSIN...POSSIBLY AS A RESULT OF STRENGTHENING MID-LEVEL FGEN. NOT SURE WHAT TO MAKE OF THIS SCENARIO...SINCE THIS LINE OF SHOWERS HAS STRUGGLED DUE TO THE PRESENCE OF AMPLE DRY AIR...AS DEPICTED ON AREA 12Z SOUNDINGS. WILL TREND POPS UPWARD OVER FAR NE WISCONSIN LATE IN THE EVENING...BUT REMAIN MORE CONSERVATIVE WITH QPF THAN THE MODELS. THEN A STRONG COLD FRONT WILL SWEEP ACROSS THE AREA EXCEPT FOR THE DOOR PENINSULA AFTER MIDNIGHT. A RELATIVELY CLEAN DRY SLOT WILL BE COINCIDENT WITH THIS FRONT SO PRECIP CHANCES WILL REMAIN SMALL. BUT THE MESOMODELS AND NAM CREATE ELEVATED CAPE UP TO ABOUT 100 J/KG ALONG THE FRONT...SO SUPPOSE CANNOT RULE OUT SMALL CHANCES OF SHOWERS. BEHIND THE FRONT...WINDS WILL SHIFT TO THE SOUTHWEST AND USHER IN A MODIFIED ARCTIC AIRMASS. PLENTY OF STRATUS AND LIGHT SNOW BEHIND THE FRONT WITHIN THE COMMA HEAD SO WILL INTRODUCE A CHANCE OF SNOW ACROSS THE FAR WESTERN TIER OF COUNTIES LATE TONIGHT. TEMPS WILL REMAIN MILD WITH BREEZY CONDITIONS UNTIL FRONTAL PASSAGE...THEN WILL DROP QUICKLY BEHIND THE FRONT. TUESDAY...THE COLD FRONT WILL FINISH CROSSING FAR NE WISCONSIN EARLY IN THE MORNING AND THEN THE COMMA HEAD OF THE CYCLONE WILL SPREAD ACROSS THE REST OF THE FORECAST AREA. THOUGH THERE ARE SOME INDICATIONS THAT MOISTURE WILL STRUGGLE TO SATURATE ABOVE THE -10C ISOTHERM...THINK THERE WILL BE ENOUGH MOISTURE FOR LIGHT SNOW OVER THE NORTHWEST HALF OF THE FORECAST AREA. INCREASED POPS OVER N-C WISCONSIN WHERE MOISTURE IS THE DEEPEST AND SHOW ABOUT A HALF INCH TO AN INCH OF ACCUMULATION. OTHERWISE...ANY LIGHT PRECIP WILL BE GRADUALLY LIFTING NORTH WITH THE COMMA HEAD THROUGH THE DAY. ANTICIPATE MOSTLY CLOUDY AND WINDY CONDITIONS WITH HIGHS RANGING THROUGH THE 30S. .LONG TERM...TUESDAY NIGHT THROUGH MONDAY ISSUED AT 250 PM CDT MON MAR 31 2014 THE MODELS CONTINUE TO FORECAST A SIGNIFICANT SPRING STORM TO MOVE FROM THE SOUTHERN PLAINS TOWARDS THE WESTERN GREAT LAKES THURSDAY AND FRIDAY. THEY AGREE THAT A UPPER TOUGH WILL INTENSIFY AS IT MOVES FROM THE DESERT SOUTHWEST TOWARDS WISCONSIN WITH SOME PHASING WITH JET ENERGY IN THE NORTHERN STREAM. THERE ARE MORE IMPORTANT DIFFERENCES IN THE LOW LEVELS ESPECIALLY CONCERNING TEMPERATURES FROM THE BOUNDARY LAYER TO AROUND 850MB. THE ECMWF IS WARMEST AND WOULD PRODUCE MORE RAIN OR FREEZING RAIN AND SLEET ACROSS EASTERN WISCONSIN WHILE THE GFS WOULD PRODUCE MOSTLY SNOW. WITH ARCTIC HIGH PRESSURE TO THE NORTH AND GULF MOISTURE STREAMING NORTHWARD THIS SHOULD BE A VIGOROUS SYSTEM CAPABLE OF PRODUCING HEAVY SNOW IN SOME PLACES AND PERHAPS SIGNIFICANT ICE IN OTHERS. THE SYSTEM IS STILL OVER THE PACIFIC SO THERE WILL LIKELY BE ADJUSTMENTS TO CURRENT FORECASTS. DRY AND COLD WEATHER WILL FOLLOW FOR SATURDAY AND SUNDAY THEN ANOTHER SYSTEM WILL ARRIVE MONDAY AND MONDAY NIGHT WITH PRECIPITATION TYPE ISSUES AS WELL. && .AVIATION...FOR 18Z TAF ISSUANCE ISSUED AT 1227 PM CDT MON MAR 31 2014 STRONG LOW PRESSURE AND ASSOCIATED COLD FRONT WILL SWEEP ACROSS THE STATE AFTER MIDNIGHT. AHEAD OF THE LOW...VFR CONDITIONS BUT WITH LLWS WILL PREVAIL. BAND OF LIGHT RAIN IS MOVING INTO THE SOUTHWEST PART OF THE STATE EARLY THIS AFTERNOON...BUT IT IS RUNNING INTO AMPLE DRY AIR AND IS EXPECTED TO DISSIPATE BY THE TIME IT REACHES THE TAF SITES. CANNOT RULE OUT A SPRINKLE...BUT CONFIDENCE IS LOW ENOUGH TO EXCLUDE A MENTION FROM THE TAFS. THE LATEST GUIDANCE ALSO REDEVELOPS THIS BAND OF RAIN THIS EVENING OVER NE WISCONSIN. WILL STILL HAVE DRY AIR AROUND...SO NOT CONFIDENT OF THIS SCENARIO OCCURRING EITHER. THEN THE COLD FRONT WILL PASS THROUGH THE REGION REGION MAINLY DURING THE 07-11Z TIME PERIOD. BEHIND THE FRONT...THE RETURN OF ARCTIC AIR WILL USHER IN A WIDESPREAD STRATUS DECK. CIGS MAY FALL BELOW MVFR LEVELS OVER N-C WISCONSIN LATE TONIGHT INTO TUESDAY MORNING. SOME LIGHT SNOW IS ALSO POSSIBLE...MAINLY ACROSS THE NORTH THAT COULD DROP VSBYS TO MVFR OR IFR...BUT LEFT AS MVFR FOR NOW. && .GRB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM.....MPC LONG TERM......RDM AVIATION.......MPC
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1248 PM CDT MON MAR 31 2014 .UPDATE... ISSUED AT 527 AM CDT MON MAR 31 2014 SHOWERS AND EMBEDDED THUNDERSTORMS HAVE EXPANDED NICELY ACROSS WESTERN IOWA ON RADAR. DESPITE THE NUMEROUS LOOKING COVERAGE...1 HOUR METAR OBSERVATIONS ARE STILL ONLY SHOWING MAINLY TRACE AMOUNTS. RAP TRENDS ARE LOOKING MORE PROMISING FOR PRECIPITATION WEST OF THE MISSISSIPPI RIVER...THOUGH...SO FELT IT IS WARRANTED TO RAISE CHANCES SOME. RAP STILL DIMINISHES THE PRECIPITATION BEFORE IT MOVES INTO SOUTHWEST AND CENTRAL WISCONSIN...WHICH MAKES SENSE AS IT RUNS INTO DRY AIR AND LOW LEVEL JET FORCING MIXES OUT. ALREADY INTRODUCED THE POTENTIAL FOR SOME THUNDER PRIOR TO 15Z WEST OF HIGHWAY 52. LOOKS LIKE THE ELEVATED INSTABILITY AND FORCING WANES THEREAFTER. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 342 AM CDT MON MAR 31 2014 A VARIETY OF IMPACTS EXIST IN THE SHORT TERM FROM AN APPROACHING NEGATIVELY TILTED SHORTWAVE. HAVE TRIED TO EXPLAIN THEM THE BEST IN AN ORGANIZED FASHION BELOW. CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS SHOWED A DEEP TROUGH JUST OFF THE U.S. WEST COAST...A NEGATIVELY TILTED VIGOROUS SHORTWAVE OVER NORTHEAST COLORADO...AND RIDGING FROM LOUISIANA INTO MICHIGAN. PLENTIFUL UPPER LEVEL MOISTURE ON WATER VAPOR WAS STREAMING FROM THE CENTRAL PLAINS INTO THE FORECAST AREA AHEAD OF THE VIGOROUS SHORTWAVE...MANIFESTING ITSELF AS SCT-BKN CIRRUS. BELOW THESE CLOUDS...A DRY AIRMASS EXISTS AS SEEN ON A 00Z 700MB AND 850MB RAOB PLOT...WITH DEWPOINT DEPRESSIONS OF 10-20C FROM THE FORECAST AREA SOUTHWEST THROUGH THE CENTRAL PLAINS. SURFACE DEWPOINTS ARE INCREASING IN THE SAME AREA...HOWEVER...NOW ABOUT 5-15 DEGREES HIGHER. THIS INCREASE WAS DUE TO A SOUTHWESTERLY 925MB WIND OF 40-55 KT FROM THE FORECAST AREA DOWN INTO TEXAS...HELPING TO BRING GULF OF MEXICO MOISTURE NORTHWARD. THE WINDS ARE ALSO HOLDING TEMPERATURES UP WITH READINGS MAINLY IN THE 40S. 925MB TEMPS WERE ANALYZED PER RAP AT 08Z OF 9-13C...NEARLY IDENTICAL TO 00Z RAOBS. TO THE WEST...A 988MB LOW WAS LOCATED JUST EAST OF ALLIANCE NEBRASKA. A NARROW BAND OF SHOWERS WERE TRYING TO DEVELOP OVER CENTRAL NEBRASKA EAST OF THIS LOW...ASSOCIATED WITH 310K ISENTROPIC LIFT. THIS PUTS THE SHOWERS ROOTED AROUND 600MB. HOWEVER...THE AFOREMENTIONED LOWER LEVEL DRY AIR HAS KEPT RAIN FROM REACHING THE GROUND. SYNOPTIC OVERVIEW...500MB HEIGHT PROGS FROM MODELS ARE NEARLY IDENTICAL NOW...BOTH IN TIMING AND STRENGTH...FOR THE TRACK OF THE VIGOROUS SHORTWAVE CURRENTLY IN NORTHEAST COLORADO. OVERALL TREND OVER THE PAST WEEK FROM MODELS WAS A SLOWER...DEEPER AND MORE NORTHWEST TRACK. CURRENT CONSENSUS TRACKS THE SHORTWAVE ACROSS WATERTOWN SD LATE THIS AFTERNOON...AND INTO THE DULUTH MN AREA BY 12Z TUE. THE ASSOCIATED SURFACE LOW CURRENTLY IN WESTERN NEBRASKA TAKES NEARLY THE SAME ROUTE...WITH THE PRESSURE WEAKENING TONIGHT AS THE LOW BEGINS TO OCCLUDE. PRECIPITATION...THE TRACK OF THE SURFACE/500MB FEATURES ARE GENERALLY NOT FAVORABLE FOR PRECIPITATION FOR THE FORECAST AREA...ESPECIALLY WITH ALL THE DRY AIR IN PLACE. IF THERE WAS MORE GULF OF MEXICO MOISTURE TO WORK WITH...SAY DEWPOINTS IN THE 50S...THIS MIGHT BE A DIFFERENT STORY. HOWEVER...MODELS STILL CONTINUE TO INDICATE 3 WAVES OF POTENTIAL PRECIPITATION... 1. THE FIRST IS ASSOCIATED WITH THE 310K ISENTROPIC LIFT IN CENTRAL NEBRASKA. THIS LIFT LOOKS TO TRACK NORTHEAST ACROSS THE AREA TODAY. THE PLENTIFUL LOW TO MID LEVEL DRY AIR IN PLACE MAY MAKE IT TOUGH FOR PRECIPITATION TO OCCUR. IN FACT...OVERALL MODEL TRENDS CONTINUE TO SUGGEST LESS AND LESS PRECIPITATION WITH THIS FIRST WAVE...WITH THE REGIONAL CANADIAN AND TO SOME DEGREE THE RAP EVEN SUGGESTING DRY. HAVE LOWERED CHANCES TO 20-30 WITH THIS WAVE. 2. THE SECOND WAVE OF POSSIBLE PRECIPITATION COMES DURING THE EVENING HOURS ASSOCIATED WITH THE LOWS COLD FRONT. THERES A GOOD MODEL CONSENSUS FOR A NARROW LINE OF SCT-BKN SHOWERS TO DEVELOP NEAR I-35 NEAR 00Z...CORRELATING WELL WITH AN AXIS OF WEAK TO MODERATE 0- 2KM MOISTURE CONVERGENCE AND THE LEFT EXIT REGION OF AN UPPER JET. 31.00Z NAM SOUNDINGS SHOW A BRIEF 1 HOUR PERIOD OF THE SHOWERS... WHERE ALSO CAPE ROOTED ABOVE 850MB CLIMBS TO 200-300 J/KG. THIS CAPE AND FORCING SHOULD BE ENOUGH TO GENERATE SOME ISOLATED THUNDER. GIVEN LIKELY INVERTED-V SOUNDING AND 850MB WINDS OF 45-50 KT...THE SHOWERS AND THUNDERSTORMS COULD PRODUCE STRONG TO POSSIBLY EVEN DAMAGING WIND GUSTS. AGAIN...THIS WILL BE ISOLATED. 3. THE FINAL WAVE OF PRECIPITATION IS THE COLD CONVEYOR BELT OF SNOW WRAPPING AROUND THE SYSTEM...POSSIBLY IMPACTING THE FORECAST AREA AFTER MIDNIGHT. MODELS CONTINUE TO TREND MORE AND MORE NORTHWEST WITH THE REACH OF THE COLD CONVEYOR. AS IT STANDS NOW...LOCATIONS MAINLY NORTHWEST OF A LINE FROM AUSTIN MN TO WAUSAU WI LOOK TO SEE THE SNOW. IN ADDITION...THE SNOW MAY NOT ARRIVE UNTIL AFTER 09Z. AS SUCH...ANY ACCUMULATIONS PRIOR TO 12Z WILL BE VERY LIGHT. TEMPERATURES...925MB READINGS ARE PROGGED TO MOSTLY HOLD IN THE 9- 13C RANGE THROUGHOUT THE DAY...WARMEST TOWARDS THE LATE AFTERNOON AT TIME OF PEAK MIXING. THE WARMER START TO THE DAY PLUS LIMITED IMPACT FROM PRECIPITATION WOULD SUPPORT A WARMER SCENARIO. IN ADDITION...IT APPEARS WE SHOULD HAVE SOME SUN BOTH EARLY IN THE DAY AND AGAIN LATER IN THE AFTERNOON. WITH A BREEZY SOUTH WIND AIDING IN ADVECTING WARMER AIR IN FROM THE SOUTH TOO...SEEMS LIKE A SITUATION TO LEAN TOWARDS THE WARMER SIDE OF GUIDANCE. DO THINK...THOUGH...THE MET SHOWING 70-71 FOR BLACK RIVER FALLS...WINONA AND BOSCOBEL IS A BIT TOO AMBITIOUS. READINGS WILL REALLY TAKE A TUMBLE TONIGHT AS COLD AIR WRAPS AROUND THE SURFACE LOW. BY 12Z TUE...925MB TEMPS ARE PROGGED BETWEEN -5 AND -7C. A 30 DEGREE TEMPERATURE DROP IS POSSIBLE BETWEEN 00Z AND 12Z. WINDS...925MB WINDS OF 30-40 KT HOLD NEARLY STEADY THROUGH MUCH OF THE DAY...BUT IT DOES APPEAR THESE SHOULD PICK UP TOWARDS 45 KT AS THE LOW AND FRONT NEAR. THE STRONGEST WINDS STILL LOOK TO OCCUR ALONG/SOUTH OF I-90. THE DAYTIME MIXING PLUS ISALLOBARIC HELP SHOULD PUSH WIND GUSTS TOWARDS THE 35-45 MPH RANGE. CANNOT RULE OUT SOME HIGHER GUSTS. THEN WE HAVE THE COLD FRONTAL PASSAGE TONIGHT WITH 925MB WINDS ALSO 30-40 KT AIDED TOO BY A PRESSURE RISE. MUCH OF THIS SHOULD EASILY MIX DOWN...RESULTING IN GUSTS OF 30-40 MPH WITH MAYBE SOME HIGHER ONES TOWARDS 45 MPH. AFTER COLLABORATION WITH MPX...DMX...DVN AND MKX...SETTLED ON A WIND ADVISORY FOR MOSTLY THE COUNTIES ALONG/WEST OF US-52. THIS ADVISORY MAY NEED EXPANSION TO THE EAST INTO FAR SOUTHWEST WI DURING THE DAY SHIFT. FOR NOW PUT THESE COUNTIES IN AN SPS. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 342 AM CDT MON MAR 31 2014 ACTIVE WEATHER CONTINUES AND WE REALLY NEED TO WATCH THURSDAY NIGHT AND FRIDAY CLOSELY. MODELS HAVE TRENDED A LITTLE FASTER IN EXITING THE VIGOROUS SHORTWAVE TROUGH AND SURFACE LOW TO THE NORTHEAST. AS SUCH...HAVE SPED UP THE EXITING OF THE COLD CONVEYOR BELT SNOW AND BRINGING IN CLEARING QUICKER. WITH A FASTER EXIT...IT APPEARS THOSE LOCATIONS THAT DO SEE SNOW WILL SEE VERY LITTLE. VERY WINDY CONDITIONS TO START OFF THE DAY...ESPECIALLY ACROSS SOUTHEAST MN WHERE A SECONDARY COLD FRONT PASSES...SHOULD SLOWLY DIMINISH THROUGH THE DAY. BETTER SHOT TO LIGHTEN UP THE WINDS COMES TUESDAY NIGHT AS A RIDGE OF HIGH PRESSURE BUILDS IN FOR LOCATIONS NORTH OF I-90. THE NEXT CONCERN ON THE HORIZON INVOLVES THE DEEP UPPER TROUGH OFF THE PACIFIC NORTHWEST COAST. SUBJECTIVELY...THAT TROUGH LOOKS A LOT MEANER THAN THE ONE COMING INTO THE PLAINS RIGHT NOW. MODELS ARE IN VERY GOOD AGREEMENT DIGGING THIS FEATURE INTO THE SOUTHWESTERN U.S. ON WEDNESDAY...CAUSING RIDGING AND A WARM ADVECTION PATTERN TO DEVELOP DOWNSTREAM FROM THE GULF COAST INTO THE LOWER GREAT LAKES. THE BIG PROBLEM HERE IS THAT THE WARM ADVECTION PATTERN MOSTLY OCCURS ALOFT...AS THE LOW LEVELS ARE DOMINATED BY AN EASTERLY FLOW COMING OUT OF COLD...CANADIAN HIGH PRESSURE OVER THE NORTHERN GREAT LAKES AND ONTARIO. THIS SETS THE STAGE FOR POSSIBLE MIXED PRECIPITATION. 31.00Z GFS/NAM/ECMWF ARE ALL INDICATING A LEAD WAVE OF WARM ADVECTION PRECIPITATION IMPACTING MAINLY LOCATIONS SOUTH OF I-90 WEDNESDAY NIGHT INTO THURSDAY MORNING. THERE ARE CONCERNS WITH A WARM LAYER ALOFT AND LOSS OF ICE IN THE CLOUDS TO IMPACT PRECIPITATION TYPE. IN ADDITION...EVAPORATIVE COOLING FROM THE EASTERLY FLOW OF DRY AIR COMBINING WITH THE PRECIPITATION MAY SEND TEMPERATURES AT OR BELOW FREEZING. AS A RESULT...FORECAST INCLUDES A VARIETY OF PRECIPITATION TYPES. ATTENTION THEN TURNS TO THE TROUGH WHICH THE GFS/GFS ENSEMBLE/UKMET AND CANADIAN ARE ALL TRENDING TOWARDS THE DEEP ECMWF SOLUTION. THIS TROUGH LIFTS UP INTO THE FORECAST AREA ON FRIDAY...BRINGING WITH IT A MUCH DEEPER PLUME OF GULF MOISTURE ALONG WITH A FAIRLY DEEP SURFACE LOW. THERE ARE INDICATIONS WE COULD SEE ACCUMULATING WET SNOW...PARTICULARLY OVER OUR NORTHWEST...TO MIXED PRECIPITATION AND EVEN HEAVY RAINFALL. THERE MAY EVEN BE SOME THUNDERSTORMS OVER FAR SOUTHWEST WI THURSDAY NIGHT...BUT THE PROBABILITY IS TOO LOW TO INCLUDE AT THIS TIME. NEEDLESS TO SAY...RAISED PRECIPITATION CHANCES INTO THE 60-70 RANGE FOR MOST LOCATIONS THURSDAY NIGHT AND FRIDAY. LOOKS LIKE THE SYSTEM WILL GRADUALLY EXIT THE AREA FRIDAY NIGHT WITH DRIER AND WARMER WEATHER TO FOLLOW FOR THE WEEKEND AS HIGH PRESSURE BUILDS IN. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 1248 PM CDT MON MAR 31 2014 A TIGHT PRESSURE GRADIENT WILL DEVELOP ACROSS THE AREA EARLY THIS AFTERNOON AND THEN CONTINUE INTO TUIESDAY MORNING. KRST WILL SEE SUSTAINED WINDS BETWEEN 20 AND 25 KNOTS WITH GUSTS UP TO 40 KNOTS. KLSE WILL SEE SUSTAINED WINDS AROUND 20 KNOTS WITH WIND GUSTS UP TO 35 KNOTS. THE WINDS WILL BE SOUTH THIS AFTERNOON...AND THEN SHIFT TO SOUTHWEST THIS EVENING...AND WEST OVERNIGHT. BETWEEN 31.23Z AND 01.04Z A LINE OF SCATTERED SHOWERS AND IOSOLATED THUNDERSTORMS WILL MOVE EAST ACROSS THE FORECAST AREA. THE LINE WILL MOVE THROUGH KRST AROUND 01.00Z AND KLSE AROUND 01.02Z. DRY AIR BELOW THE CLOUD BASE MAY ENHANCE THE WIND GUSTS FROM THIS CONVECTION RESULTING IN MUCH STRONGER WIND GUSTS POSSIBLY AS HIGH AS 50 KNOTS. BEHIND THIS LINE...THERE WILL BE A BROKEN 2500 TO 3500 FOOT DECK. THIS LINE WILL PERSIST THROUGH TUESDAY MORNING. && .FIRE WEATHER... ISSUED AT 342 AM CDT MON MAR 31 2014 BREEZY SOUTHERLY WINDS COMBINED WITH TEMPERATURES CLIMBING INTO THE MID 60S THIS AFTERNOON POSES SOME CONCERN FOR FIRE WEATHER. DEWPOINTS ALSO SHOULD MIX A BIT THIS AFTERNOON...PARTICULARLY OVER CENTRAL AND FAR SOUTHWEST WI WHICH SAW THAT HAPPEN YESTERDAY. FUELS ALSO WERE ABLE TO DRY OUT SOME FROM YESTERDAY. HOWEVER...RELATIVE HUMIDITY VALUES ONLY DROP TO A MINIMUM OF 35 PERCENT...PRECLUDING THE NEED FOR ANY FIRE WEATHER HAZARDS. ANOTHER ITEM TO WATCH IS ISOLATED THUNDERSTORMS COMING ACROSS THE AREA THIS EVENING. GIVEN THAT DRY AIR EXISTS BELOW THE CLOUD BASES...THESE THUNDERSTORMS MAY NOT PRODUCE MUCH RAINFALL. THUS...CANNOT RULE OUT SOME DRY LIGHTNING STRIKES. THE STORMS SHOULD ALSO PRODUCE SOME STRONG WINDS...SO IF A FIRE WOULD GET STARTED...THE WIND COULD HELP IT SPREAD A LITTLE. && .HYDROLOGY... ISSUED AT 342 AM CDT MON MAR 31 2014 FLOOD WATCH REMAINS ON TRACK FOR TREMPEALEAU...JACKSON AND CLARK COUNTIES. BOTH THE BLACK AND TREMPEALEAU RIVERS ARE RESPONDING TO THE SNOWMELT THAT HAS OCCURRED YESTERDAY THROUGH NOW. CONTINUED RAPID SNOWMELT OVER THE NEXT 24 HOURS FROM TEMPERATURES PEAKING UP IN THE MID 50S TO LOW 60S WILL ALLOW THE RIVERS TO CONTINUE RISING. IT APPEARS LIKELY THAT FLOOD WARNINGS WILL BE ISSUED SOMETIME TODAY...PARTICULARLY ON THE BLACK SINCE THE TREMPEALEAU RIVER BASIN MAY BE EXHAUSTED OF SNOWMELT. SHOULD BE A CLOSE CALL ON THE TREMPEALEAU AT DODGE...THOUGH. LOOKING AHEAD TO LATER IN THE WEEK...CONCERN IS GROWING OF A POSSIBLE HEAVY RAINFALL EVENT OVER THE SOUTHEAST HALF OF THE AREA THURSDAY NIGHT AND FRIDAY. WE WILL HAVE TO WATCH THIS TIME PERIOD CLOSELY. LUCKILY THERE ISNT GOING TO BE ANY SNOWMELT OVER THAT AREA. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...FLOOD WATCH FROM LATE TONIGHT THROUGH THURSDAY MORNING FOR WIZ029-033-034. MN...WIND ADVISORY UNTIL 10 AM CDT TUESDAY FOR MNZ086-087-094-095. IA...WIND ADVISORY UNTIL 7 AM CDT TUESDAY FOR IAZ008>010-018-019-029. && $$ UPDATE...AJ SHORT TERM...AJ LONG TERM...AJ AVIATION...BOYNE FIRE WEATHER...AJ HYDROLOGY...AJ