Forecast Discussions mentioning any of "HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 09/28/15


AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
956 PM MDT SUN SEP 27 2015 .UPDATE... ISSUED AT 956 PM MDT SUN SEP 27 2015 SOME THIN HIGH CLOUD ACROSS THE FORECAST AREA...BUT MUCH OF THE REGION IS ABLE TO OBSERVE THE SUPERMOON ECLPISE. THE HRRR MAY BE OVERDOING THE THREAT OF PRECIPITATION OVER THE UINTA MOUNTAINS TONIGHT. DO NOT SEE ANY EVIDIENCE THAT SHOWERS ARE FORMING ON SALT LAKE`S RADAR OUR OURS...SO TEMPERED THE POP GRIDS A BIT IN THE EVENING UPDATE. APPEARED THAT SHOWERS DID FORM ALONG THE NRN BORDER OF DAGGETT COUNTY BEFORE SUNSET...BUT THESE HAVE SINCE DISSIPATED. && .SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT) ISSUED AT 326 PM MDT SUN SEP 27 2015 THE UPPER RIDGE THAT HAS BEEN OVER THE REGION WILL CONTINUE TO FLATTEN AND SHIFT TO THE SOUTHWEST DURING THE NEXT COUPLE OF DAYS. AS A RESULT THE FLOW WILL BECOME MORE WESTERLY AND CARRY A COUPLE OF WEAK WAVES FROM WEST TO EAST...MAINLY NORTH OF OUR FORECAST AREA. THE TAIL END OF ONE WAVE WILL BRUSH OUR NORTHERN EDGE TONIGHT. AS A RESULT WE HAVE SEEN A BETTER CUMULUS DEVELOPMENT OVER THE UINTA...FLATTOPS AND PARK RANGES THIS AFTERNOON. A FEW SHOWERS AND THUNDERSTORMS MAY ALSO DEVELOP LATE THIS AFTERNOON AND EARLY THIS EVENING. OF MOST INTEREST FOR TONIGHT`S FORECAST WILL BE THE AMOUNT OF EXPECTED CLOUD COVER FOR THE LUNAR ECLIPSE THIS EVENING. IT APPEARS SOME HIGH CLOUDS MAY FILTER THE VIEW FOR MUCH OF THE AREA...BUT THESE CLOUDS WILL GENERALLY BE THIN. THE EXCEPTION WILL BE FROM AROUND THE TAVAPUTS PLATEAU/FLATTOPS AND NORTH...WHERE CLOUDS MAY BE A LITTLE THICKER. BUT EVEN THERE THE MOON SHOULD BE SOMEWHAT VISIBLE. OVERNIGHT TEMPS ARE EXPECTED TO BE A LITTLE WARMER DUE TO THE BETTER CLOUDS. ENERGY WILL CONTINUE TO ROUND THE TOP OF THE RIDGE AND BRUSH THE NORTHERN EDGE OF OUR FORECAST AREA THROUGH MON NIGHT. THEREFORE A FEW SHOWERS AND LATE DAY THUNDERSTORMS WILL CONTINUE TO BE POSSIBLE ACROSS THE NORTH...FAVORING THE HIGHER TERRAIN. LITTLE CHANGE IS EXPECTED IN AFTERNOON HIGH TEMPERATURES ON MONDAY... WITH LOWS INCREASING JUST A LITTLE MONDAY NIGHT. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 326 PM MDT SUN SEP 27 2015 A FEW SHOWERS AND THUNDERSTORMS WILL CONTINUE OVER THE NORTH ON TUESDAY...POSSIBLY LINGERING OVERNIGHT AS ANOTHER WAVE BRUSHES THE FORECAST AREA. ON WED THE RIDGE WILL REBOUND ALONG THE UT/CO BORDER...PUMPED UP BY THE NEXT LOW PRESSURE TROUGH APPROACHING THE WEST COAST. WHILE THE MID TERM MODELS ARE IN FAIR AGREEMENT ON THE BIG PICTURE...THERE CONTINUES TO BE SOME RATHER SIGNIFICANT TIMING DIFFERENCES IN WHEN THIS LOW PRESSURE SYSTEM AND ITS ASSOCIATED COLD FRONT WILL REACH THE FORECAST AREA...AND IN HOW QUICK THE TROUGH EXITS TO THE EAST. IN ANY CASE...THE RIDGE WILL DOMINATE WED AND THU AHEAD OF THE TROUGH. SOUTHWEST WINDS WILL PICK UP ON THU AS THE GRADIENT TIGHTENS AHEAD OF THE SYSTEM AS IT MOVES INTO THE GREAT BASIN. THE ECMWF IS FASTER BY AROUND 12 HOURS...WITH THE COLD FRONT JUST ABOUT TO OUR NORTHWEST CORNER AT 00Z FRI. THE EC ALSO SHOWS THE LOW CENTER QUICKLY BRUSHING OUR NORTHERN EDGE EARLY FRIDAY AND EAST OF THE FORECAST AREA BY THE AFTERNOON. A SHORTWAVE RIDGE THEN FOLLOWS FOR SUN. AS MENTIONED ABOVE...THE GFS IS AROUND 12 HOURS SLOWER...WITH THE FRONT REACHING THE NORTHWEST CORNER AT AROUND 12Z FRI. IN THIS SOLUTION THE LOW CENTER WILL MOVE OVER NE UT/NW CO/SW WY FRI EVENING...AND LINGER OVER NORTHWEST CO THROUGH EARLY SAT. ENERGY THEN SPLITS OFF THE MAIN LOW AND RETROGRADES...LEAVING GENERAL TROUGHINESS OVER WY TO THE GREAT BASIN THROUGH SUN. FOR NOW HAVE KEPT THE BEST CHANCE OF SHOWERS/THUNDERSTORMS ON FRI AFTERNOON...WITH A DOWNTURN AFTER THAT. EXPECT THAT THE FORECAST WILL CONTINUE TO BE ADJUSTED AS THIS SYSTEM NEARS AND MODEL SOLUTIONS EVOLVE. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING) ISSUED AT 556 PM MDT SUN SEP 27 2015 NORTH OF KVEL: ISOLATED -SHRA/-TSRA MAY DEVELOP TONIGHT OVER THE UINTA MOUNTAINS. THIS THREAT EXPANDS INTO NORTHWEST AFTER 18Z MONDAY AFTERNOON...PRIMARILY NORTH OF A LINE FROM KVEL-KSBS. ALTHOUGH SCATTERED -TSRA WILL FORM OVER THE HIGH TERRAIN SURROUNDING KSBS. FOR THE REMAINDER OF THE TAF SITES...P6SM WITH SCATTERED CIRRUS BECOMING WIDESPREAD BROKEN LAYER AFTER 18Z MONDAY AFTERNOON. && .GJT WATCHES/WARNINGS/ADVISORIES... CO...NONE. UT...NONE. && $$ UPDATE...PF SHORT TERM...EH LONG TERM...EH AVIATION...PF
AREA FORECAST DISCUSSION
NWS PUEBLO CO
247 PM MDT SAT SEP 26 2015 .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 240 PM MDT SAT SEP 26 2015 .SHORT TERM...(TONIGHT AND SUNDAY) CURRENTLY...UPPER RIDGE OVER THE 4 CORNERS KEPT MUCH OF THE CWA MOSTLY SUNNY AND WARM...THOUGH LOW CLOUDS AND AREAS OF FOG THIS MORNING OVER THE FAR EASTERN PLAINS SLOWED THE WARMING PROCESS CONSIDERABLY. TONIGHT AND TOMORROW...THE UPPER RIDGE ACROSS THE AREA FLATTENS OVER THE NEXT 24 HRS...BUT DRY AND WARM CONDITIONS ARE EXPECTED TO PREVAIL. MAIN FORECAST CONCERN CONTINUES TO BE WHETHER LOW CLOUDS AND/OR FOG WILL REDEVELOP ALONG THE ARKANSAS RIVER VALLEY ALONG THE EASTERN CO BORDER. MODELS INDICATE THAT THE SFC WINDS TONIGHT WILL BE MORE SOUTHERLY THEN E-SE...BUT HRRR...WRF AND RUC MODELS HINT AT EASTERLY FLOW CONTINUING RIGHT ALONG THE ARKANSAS TONIGHT THROUGH ABOUT 13Z. THIS WOULD AID IN SOME LOW CLOUD/FOG DEVELOPMENT FOR OTERO...BENT AND PROWERS COUNTIES...AND PORTIONS OF KIOWA AND BACA COUNTIES AS WELL...WITH KLHX AND KLAA BEING THE MAIN AREAS AFFECTED. THEREFORE...INCREASED CLOUD COVER AND INTRODUCED AREAS OF FOG FROM 06Z-13Z TONIGHT. ANY FOG THAT DOES DEVELOP SHOULD BE RELATIVELY SHORT-LIVED AND NOT BECOME DENSE. OVERNIGHT MIN TEMPS ARE EXPECTED TO DROP TO AROUND 50F FOR THE PLAINS...30S AND 40S FOR THE HIGH VALLEYS. MAX TEMPS TOMORROW WILL CLIMB INTO THE 80S FOR MOST AREAS...60S AND 70S FOR THE MTS. MOORE .LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY) ISSUED AT 240 PM MDT SAT SEP 26 2015 ...PATTERN TO BECOME A BIT MORE ACTIVE... THE PATTERN WILL LIKELY BECOME A BIT MORE ACTIVE THIS PERIOD AS LONG RANGE GUIDANCE INDICATES A COUPLE OF SHORT WAVES WILL MOVE ACROSS THE REGION...AND THEY SHOULD BRING SOME COOLER TEMPS ALONG WITH A CHANCE OF SOME SCTD PRECIP TO THE REGION. MONDAY... ANOTHER VERY WARM DAY EXPECTED ACROSS THE REGION WITH TEMPS RUNNING WELL ABOVE NORMAL ALL AREAS. MAX TEMPS ON MOST OF THE PLAINS WILL BE IN THE 85 TO 90F RANGE WITH 80S IN EL PASO COUNTY. TEMPS IN THE VALLEYS WILL ALSO BE WARM WITH 70S TO AROUND 80F. AN ISOLD SHOWER WILL BE POSSIBLE IN THE HIGHER ELEVATIONS. TUESDAY... A WEAK COOL FRONT IS PROJECTED TO COME DOWN THE PLAINS SOMETIME TUESDAY MORNING AS A WEAK WAVE AT MIDDLE LEVELS MOVES TO OUR NORTH. WEAK UPSLOPE FLOW ALONG WITH SOME CAPE SHOULD ALLOW FOR ISOLD TSRA TO DEVELOP OVER THE HIGHER TRRN...ESPECIALLY ALONG THE PLAINS/MTNS INTERFACE. TEMPS WILL BE A BIT COOLER REGIONWIDE WITH HIGHS ON THE PLAINS RANGING FROM THE 70S ACROSS N EL PASO COUNTY TO MID 80S ACROSS THE LOWER ARK RVR VALLEY. TEMPS WILL STILL BE QUITE MILD IN THE VALLEYS WITH 70S EXPECTED. WEDNESDAY... WE GET HOT AGAIN WITH TEMPS ACROSS THE REGION SIMILAR TO MONDAYS HIGHS. IT WILL LIKELY BE DRY ACROSS THE FCST AREA AS RIDGING ALOFT BUILDS OVER THE STATE. THURSDAY... BOTH MODELS SHOW A MORE POTENT SHORT WAVE COMING TOWARDS THE REGION FROM THE WEST ON THIS DAY. GFS IS A BIT WEAKER BUT QUICKER WITH THE SYSTEM WHILE THE EC IS STRONGER AND A BIT SLOWER. IN EITHER CASE THURSDAY WILL LIKELY BE HOT ONCE AGAIN IN ADVANCE OF THIS SHORT WAVE WITH MID 80S TO L90S ACROSS THE PLAINS...AND 70S VALLEYS. FOR NOW...I ONLY HAVE SLIGHT POPS IN THE C MTNS THURSDAY EVENING. FRIDAY... THERE IS A GOOD CHANCE THAT A COLD FRONT WILL CROSS THE REGION SOMETIMES LATE THURSDAY OR EARLY FRIDAY. IF EC IS CORRECT...WE WILL SEE A CHANCE OF PRECIP OVER THE REGION...ESPECIALLY IN THE MTNS. IF THE GFS IS CORRECT...POPS CHANCES WILL BE LESS AS SHORT WAVE IS WEAKER AND MORE PROGRESSIVE. ATTM...MAX TEMPS FOR THU ARE PROJECTED TO BE IN THE 70S TO LOWER 80S....BUT I THINK THESE VALUES MAY BE A BIT WARM NO MATTER WHAT GUIDANCE VERIFIES. I WOULD NOT BE TOO SURPRISED IF LATER NDFD FCST COME IN COOLER FOR MAX TEMPS ON FRIDAY. SATURDAY... MORE SEASONABLE TEMPS ARE LIKELY AND IT WILL LIKELY BE DRY. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING) ISSUED AT 240 PM MDT SAT SEP 26 2015 VFR CONDITIONS EXPECTED FOR THE NEXT 24 HRS OVER MUCH OF THE FORECAST AREA...INCLUDING THE THREE MAIN TAF SITES OF KCOS...KPUB AND KALS. SFC WINDS ALONG THE KANSAS STATE LINE ARE EXPECTED TO STAY MORE SOUTHERLY TONIGHT...INSTEAD OF E-SE...SO ANY LOW CLOUDS OR FOG DEVELOPMENT SHOULD REMAIN ALONG THE ARKANSAS RIVER VALLEY IN BENT AND PROWERS COUNTIES...MAINLY AFFECTING KLAA. HOWEVER...LIGHT FOG IN KLHX IS A POSSIBILITY AS WELL BETWEEN 08-13Z. FOG IS NOT ANTICIPATED TO BECOME DENSE AS IT DID THE PREVIOUS NIGHT. && .PUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...MOORE LONG TERM...HODANISH AVIATION...MOORE
AREA FORECAST DISCUSSION
NWS TALLAHASSEE FL
1013 PM EDT SUN SEP 27 2015 .Near Term [Through Tonight]... The 8 pm EDT regional surface analysis showed a complex weather pattern across the Gulf of Mexico. There was a non-tropical 1008 mb low centered off the TX-LA coast, with a developing frontal zone east of this low extending across central FL. A relatively strong high pressure ridge was building down the Piedmont, and the gradient between these two features was causing the wind speeds to increase across the Gulf coastal waters. There was another 1008 mb low, the one we have been monitoring for possible tropical development over the past few days, emerging off the northern coast of the Yucatan. It remains disorganized, with sporadic deep moist convection well away from the broad low- level center. The UW CIMSS site indicates 30-40 kt of shear over this system, and with a nearby surface low in the northwest Gulf disrupting potential low- level inflow to its west, it remains doubtful that this system will become a tropical cyclone. However, deep layer moisture associated with this slowly approaching low, and Q-G forcing associated with the deep layer low over the western Gulf as well as nearby frontogenesis to our south, will bring periods of rain to our region the next few days. For tonight, the highest Pop will be west and south of Tallahassee, where the best combination of deep layer moisture and Q-G forcing coincides. We do not expect much in the way of heavy rain or severe weather overnight, though the environment could become a little more favorable on Monday. && .Aviation... [Through 00Z Tuesday]...As has been the case the past several model cycles, the GFS and NAM MOS continue to maintain IFR or lower cigs through the period, while the HRRR and other high- resolution NWP guidance have mainly MVFR levels. Our forecast is a compromise, with predominantly low-end MVFR cigs (1-2k ft AGL). Periods of light to moderate RA are expected at KECP later tonight, lasting for the entire period, and at the other terminals in our forecast area Monday and Monday night. Occasionally heavy RA is likely as well, accompanied by IFR Vis and cigs. TSRA will be isolated. E-NE winds around 10 KT will persist. && .Prev Discussion [418 PM EDT]... .Short Term [Monday Through Tuesday Night]... A weak low pressure system moving through the Gulf of Mexico approaches the coast in the short term and the center moves on shore Tuesday. The effects of this system are already being felt today with rain across the CWA, however the main impacts will be during the short term period. The 12z ECMWF came a little more in line with the GFS today with a more westward track of the center but it isn`t quite as far west as the GFS. The NAM is slightly faster than the GFS and a tad bit further west than the GFS. GFS still appears to be the compromise in terms of track and given its consistency run to run and similarities to previous forecast, have once again leaned towards the GFS for much of the short term forecast. Deep layer moisture will be in place at the start of the short term and the PWs continue to remain in record territory with values on the GFS BUFR sounding ranging from 2.3 to 2.5 inches Monday through Monday night. Although there is a high chance of rain through Tuesday, the best chances are forecast for Monday and Monday night with nearly a 100% chance of rain along the coast and 70% chance further inland. This time period corresponds to when the threat for heavy rain is the greatest and more details can be found in the hydro section. During this time period (Monday to Monday night), the better chances for thunderstorms will be closer to the coast where instability is greater. Local hi-res models support decent helicity values Monday and Monday night and thus the potential exists for an isolated tornado with the best chances mainly south of I-10. The surface low is forecast to move across the Florida panhandle on Tuesday and have continued with the higher rain chances, but this begins to taper off Tuesday night as the sfc low continues to track northeast. .Long Term [Wednesday Through Sunday]... An upper level trough deepens across the Southeast on Wednesday which helps to keep above normal rain chances across the CWA. Big differences between the GFS and ECMWF by the end of the week though. GFS dives a closed upper level low in the aforementioned trough southward while the ECMWF is more subtle with a weak shortwave in the upper level flow. Either way, there should be a drying trend for the weekend. .Marine... Easterly winds will continue through tonight ahead of a low pressure system. Have already seen an increase in wind speeds and this increase will continue through Tuesday. Given the higher speeds, will include a Small Craft Exercise Caution statement through Monday night, however an Advisory may be needed on Monday given increasing wave heights. .Fire Weather... Hazardous fire weather conditions are not expected over the next several days as heavy rains are expected to overspread the region. .Hydrology... Primary focus will continue to be on the approaching storm system and the associated heavy rain threat. High-res guidance suggests the threat for the heaviest rainfall will be nearer to the coast and not as far inland as indicated yesterday. As a result, storm total rainfall amounts for this event have been adjusted. Storm total rainfall of 2 to 3 inches is anticipated across the Florida Panhandle and into the Florida Big Bend with isolated heavier totals possible. Further inland, rainfall amounts should generally be around 1 to 2 inches. With the heavier amounts nearer to the coast, area rivers will be able to handle this event without reaching flood stage given the recent dry conditions. With current streamflows, we`d need several inches of rain to get into the upper portions of many of the larger rivers and streams to produce river flooding - which is something we don`t see happening with this particular event. With the overall lower forecasted rainfall amounts, in addition to the low confidence in regards to the rainfall placement, the situation is not supportive of a Flash Flood Watch at this time and will let the midnight shift re-evaluate. && .Preliminary Point Temps/PoPs... Tallahassee 72 81 74 84 73 / 50 100 80 60 40 Panama City 73 80 74 82 74 / 70 100 80 60 40 Dothan 69 79 71 82 69 / 40 70 80 60 40 Albany 69 81 72 82 71 / 20 70 70 60 50 Valdosta 71 82 73 83 72 / 30 70 70 60 40 Cross City 72 84 74 84 74 / 40 80 80 70 40 Apalachicola 75 81 77 82 74 / 70 100 80 60 40 && .TAE WATCHES/WARNINGS/ADVISORIES... FL...NONE. GA...NONE. AL...NONE. GM...NONE. && $$ NEAR TERM...FOURNIER SHORT TERM...FIEUX LONG TERM...FIEUX AVIATION...FOURNIER MARINE...FIEUX FIRE WEATHER...HARRIGAN HYDROLOGY...GODSEY
AREA FORECAST DISCUSSION
NWS MIAMI FL
757 PM EDT SUN SEP 27 2015 .AVIATION... SIMILAR CONSTRAINTS TO WIDESPREAD CONVECTION ON MONDAY, AS THERE WAS TODAY. MIDLEVELS TEMPS ARE FORECAST TO WARM EVEN FURTHER MONDAY AND RESULTING MIDLEVEL LAPSE RATES ARE WEAK. DESPITE THE MORE FAVORABLE WIND PROFILE FOR EAST COAST ACTIVITY, THICK HIGH CLOUDS AGAIN COULD LIMIT COVERAGE. IF LINE OF SHOWERS AND STORMS HOLDS TOGETHER TO THE GULF COAST, APF COULD IMPACTED WITH MVFR/IFR CONDS LATER TONIGHT. WHAT`S LEFT OF THIS LINE, OR ADDITIONAL DEVELOPMENT MAY CROSS SOME OF THE EAST COAST TERMINALS INTO DAWN, SOME POTENTIALLY WITH BRIEF MVFR CIGS. && .PREV DISCUSSION... /ISSUED 739 PM EDT SUN SEP 27 2015/ UPDATE... AFTERNOON CONVECTION WAS TAME TODAY COMPARED WHAT COULD HAVE BEEN DUE TO HEAVY MID TO HIGH LEVEL CLOUD COVER WHICH SUBSTANTIALLY REDUCED DIURNAL HEATING. EVEN THOUGH, PLENTY OF MOISTURE CONTINUES TO PULLED NORTHWARD AHEAD OF THE DEVELOPING LOW PRESSURE OVER THE SOUTHERN GULF WITH A LINE OF CONVECTION NOW MOVING ACROSS THE FLORIDA STRAITS AND THE KEYS. THE QUESTION IS WHETHER OR NOT THIS BAND WILL HOLD TOGETHER. DUE TO THE DIURNAL CYCLE, THE HRRR SHOWS IT MOVING TO THE SOUTHERN AND SOUTHWESTERN COASTAL AREAS AND THEN RAPIDLY WEAKENING AS IT MOVES ASHORE. CANNOT ARGUE WITH THAT SET UP AND PLAN TO ADJUST THE GRIDS ACCORDINGLY. KOB PREV DISCUSSION... /ISSUED 400 PM EDT SUN SEP 27 2015/ .CORRECTED EXTENDED PERIOD TIMING AND MARINE PARAGRAPH... SHORT TERM (TONIGHT-TUESDAY NIGHT)... A LARGE CUT-OFF MID/UPPER LEVEL LOW PRESSURE AREA CONTINUES NEAR THE TEXAS/GULF COAST THIS AFTERNOON WITH A SURFACE LOW DEVELOPING OVER THE SOUTHERN GULF OF MEXICO JUST NORTH OF THE YUCATAN PENINSULA. THIS IS FEEDING COPIOUS AMOUNTS OF MOISTURE ACROSS SOUTH FLORIDA WITH SCATTERED SHOWERS AND A FEW THUNDERSTORMS. HOWEVER, THE HEAVY CLOUD COVER ASSOCIATED WITH THE MOISTURE BAND IS SIGNIFICANTLY REDUCING DIURNAL HEATING AND THE ACTIVITY IS NOT AS WIDESPREAD AS IT COULD HAVE BEEN IF SUFFICIENT SUNSHINE HAD BEEN IN PLACE. THEREFORE, HAVE CUT BACK ON POPS ESPECIALLY ACROSS THE INTERIOR WHICH HAS SEEN VERY LITTLE THIS AFTERNOON. THE CUT- OFF LOW WILL BEGIN TO LIFT TO THE EAST TUESDAY NIGHT AS AN UPSTREAM TROUGH MOVES INTO THE EASTERN STATES. HIGH MOISTURE CONTENT WITH PWAT VALUES AT 2"+ WILL THEREFORE CONTINUE THROUGH THE SHORT TERM WITH A CHANCE OF SHOWERS AND THUNDERSTORMS EACH PERIOD, MOSTLY DURING THE AFTERNOON AND ACROSS THE INTERIOR. IN ADDITION, MINOR COASTAL FLOODING WILL CONTINUE ALONG BOTH COASTS AS ASTRONOMICAL HIGH TIDES OCCUR WITH THE PEAK BEING ON TUESDAY. THE HIGH TIDES ALSO COINCIDE WITH THE "SUPER MOON" TONIGHT SO THE FLOODING WILL BE POSSIBLE AT TIMES OF HIGH TIDE THROUGH THE PERIOD. PLEASE REFER TO CFWMFL FOR FURTHER DETAILS. LONG TERM (WEDNESDAY-SUNDAY)... AS THE TWO TROUGHS MERGE LATER THIS WEEK OVER THE SOUTHEASTERN U.S., BOTH THE GFS AND ECMWF ARE SHOWING ANOTHER CUT-OFF LOW DEVELOPING AND THIS WILL BEGIN TO PUSH THE HIGH MOISTURE TO OUR EAST. THERE ARE DIFFERENCES AS TO HOW FAR SOUTH THE LOW WILL MOVE BUT BOTH MODES ARE SHOWING A DRYING TREND BY NEXT WEEKEND. IN FACT, THE LATEST MEX GUIDANCE SHOWS DEW POINTS LOWERING TO THE MID AND UPPER 60S IN THE LAKE OKEECHOBEE REGION WHILE MAINTAINING 70 NEAR THE SOUTHEAST COAST. MARINE... A GENERAL EAST TO SOUTHEAST WIND OF 5-10 KNOTS WILL CONTINUE INTO MONDAY EXCEPT 10-15 KNOTS OVER THE GULF WATERS WITH SEAS OF 3 FEET OR LESS. THE WIND WILL THEN VEER TO THE WEST-NORTHWEST TOWARDS THE MIDDLE TO END OF THE WEEK. A SMALL NORTHEAST SWELL WILL BEGIN TO AFFECT THE ATLANTIC WATERS OFF THE PALM BEACH COUNTY COAST EARLY THIS WEEK AS LOW PRESSURE DEVELOPS OFF THE CAROLINAS COAST. AS A RESULT, ATLANTIC SEAS WILL BUILD TO 3-5 FEET OFF THE PALM BEACH COAST AND POSSIBLY TO 6 FEET MONDAY NIGHT AND TUESDAY. && .PRELIMINARY POINT TEMPS/POPS... WEST PALM BEACH 78 90 77 89 / 20 50 30 60 FORT LAUDERDALE 78 90 79 90 / 20 40 20 60 MIAMI 79 90 80 91 / 30 40 20 60 NAPLES 77 89 78 87 / 40 50 50 50 && .MFL WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. GM...NONE. && $$ SHORT TERM...30/KOB LONG TERM....30/KOB AVIATION...21/KM
AREA FORECAST DISCUSSION
NWS MIAMI FL
739 PM EDT SUN SEP 27 2015 .UPDATE... AFTERNOON CONVECTION WAS TAME TODAY COMPARED WHAT COULD HAVE BEEN DUE TO HEAVY MID TO HIGH LEVEL CLOUD COVER WHICH SUBSTANTIALLY REDUCED DIURNAL HEATING. EVEN THOUGH, PLENTY OF MOISTURE CONTINUES TO PULLED NORTHWARD AHEAD OF THE DEVELOPING LOW PRESSURE OVER THE SOUTHERN GULF WITH A LINE OF CONVECTION NOW MOVING ACROSS THE FLORIDA STRAITS AND THE KEYS. THE QUESTION IS WHETHER OR NOT THIS BAND WILL HOLD TOGETHER. DUE TO THE DIURNAL CYCLE, THE HRRR SHOWS IT MOVING TO THE SOUTHERN AND SOUTHWESTERN COASTAL AREAS AND THEN RAPIDLY WEAKENING AS IT MOVES ASHORE. CANNOT ARGUE WITH THAT SET UP AND PLAN TO ADJUST THE GRIDS ACCORDINGLY. KOB && .PREV DISCUSSION... /ISSUED 400 PM EDT SUN SEP 27 2015/ ..CORRECTED EXTENDED PERIOD TIMING AND MARINE PARAGRAPH... SHORT TERM (TONIGHT-TUESDAY NIGHT)... A LARGE CUT-OFF MID/UPPER LEVEL LOW PRESSURE AREA CONTINUES NEAR THE TEXAS/GULF COAST THIS AFTERNOON WITH A SURFACE LOW DEVELOPING OVER THE SOUTHERN GULF OF MEXICO JUST NORTH OF THE YUCATAN PENINSULA. THIS IS FEEDING COPIOUS AMOUNTS OF MOISTURE ACROSS SOUTH FLORIDA WITH SCATTERED SHOWERS AND A FEW THUNDERSTORMS. HOWEVER, THE HEAVY CLOUD COVER ASSOCIATED WITH THE MOISTURE BAND IS SIGNIFICANTLY REDUCING DIURNAL HEATING AND THE ACTIVITY IS NOT AS WIDESPREAD AS IT COULD HAVE BEEN IF SUFFICIENT SUNSHINE HAD BEEN IN PLACE. THEREFORE, HAVE CUT BACK ON POPS ESPECIALLY ACROSS THE INTERIOR WHICH HAS SEEN VERY LITTLE THIS AFTERNOON. THE CUT- OFF LOW WILL BEGIN TO LIFT TO THE EAST TUESDAY NIGHT AS AN UPSTREAM TROUGH MOVES INTO THE EASTERN STATES. HIGH MOISTURE CONTENT WITH PWAT VALUES AT 2"+ WILL THEREFORE CONTINUE THROUGH THE SHORT TERM WITH A CHANCE OF SHOWERS AND THUNDERSTORMS EACH PERIOD, MOSTLY DURING THE AFTERNOON AND ACROSS THE INTERIOR. IN ADDITION, MINOR COASTAL FLOODING WILL CONTINUE ALONG BOTH COASTS AS ASTRONOMICAL HIGH TIDES OCCUR WITH THE PEAK BEING ON TUESDAY. THE HIGH TIDES ALSO COINCIDE WITH THE "SUPER MOON" TONIGHT SO THE FLOODING WILL BE POSSIBLE AT TIMES OF HIGH TIDE THROUGH THE PERIOD. PLEASE REFER TO CFWMFL FOR FURTHER DETAILS. LONG TERM (WEDNESDAY-SUNDAY)... AS THE TWO TROUGHS MERGE LATER THIS WEEK OVER THE SOUTHEASTERN U.S., BOTH THE GFS AND ECMWF ARE SHOWING ANOTHER CUT-OFF LOW DEVELOPING AND THIS WILL BEGIN TO PUSH THE HIGH MOISTURE TO OUR EAST. THERE ARE DIFFERENCES AS TO HOW FAR SOUTH THE LOW WILL MOVE BUT BOTH MODES ARE SHOWING A DRYING TREND BY NEXT WEEKEND. IN FACT, THE LATEST MEX GUIDANCE SHOWS DEW POINTS LOWERING TO THE MID AND UPPER 60S IN THE LAKE OKEECHOBEE REGION WHILE MAINTAINING 70 NEAR THE SOUTHEAST COAST. MARINE... A GENERAL EAST TO SOUTHEAST WIND OF 5-10 KNOTS WILL CONTINUE INTO MONDAY EXCEPT 10-15 KNOTS OVER THE GULF WATERS WITH SEAS OF 3 FEET OR LESS. THE WIND WILL THEN VEER TO THE WEST-NORTHWEST TOWARDS THE MIDDLE TO END OF THE WEEK. A SMALL NORTHEAST SWELL WILL BEGIN TO AFFECT THE ATLANTIC WATERS OFF THE PALM BEACH COUNTY COAST EARLY THIS WEEK AS LOW PRESSURE DEVELOPS OFF THE CAROLINAS COAST. AS A RESULT, ATLANTIC SEAS WILL BUILD TO 3-5 FEET OFF THE PALM BEACH COAST AND POSSIBLY TO 6 FEET MONDAY NIGHT AND TUESDAY. && .MFL WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. GM...NONE. && $$
AREA FORECAST DISCUSSION
NWS JACKSONVILLE FL
352 PM EDT SAT SEP 26 2015 .CURRENTLY...ISOLD TO SCT SHOWERS OVER THE FORECAST AREA MAINLY IN NE FL SLOWLY PUSHING WWD TO NW. NOT WHOLE LOT OF INSTABILITY SO FAR WITH SBCAPE MAXIMIZED AT ABOUT 2000-2500 J/KG...BUT AIRMASS IS FAIRLY TROPICAL WITH 500 MB TEMPS OF ABOUT -6 AND NARROW CAPE ALOFT. ANTICIPATE AN UPTICK IN CONVECTION REST OF THE AFTN MAINLY INLAND WITH MAIN CONCERN LIGHTNING AND LOCALLY HEAVY DOWNPOURS...MAINLY IN NE FL. .SHORT TERM... TONIGHT...ISOLD TO SCT SHOWERS AND A FEW STORMS IN THE EVENING WILL GRADUALLY FADE WITH COASTAL TROUGH SET UP AGAIN TO PRODUCE SOME OVERNIGHT MARINE SHOWERS AND PERHAPS A TSTMS IN CONVERGENT LOW LEVEL NE FLOW. A FEW SHOWERS CANNOT BE RULED OUT FOR THE COASTAL ZONES AGAIN LATE TONIGHT AND EARLY SUNDAY COMING IN OFF THE ATLC. SIMILAR TO LAST NIGHT...LOW STRATUS AND PATCHY DENSE FOG IS LIKELY TONIGHT. RAP AND SREF SHOW A VERY MOIST LAYER AROUND 500-1000 FT WITH SREF LOW CIGS PROBABILITIES BETTER THAN 70%. LOWS TONIGHT MAINLY IN THE LOWER 70S. SUNDAY...AFTER AREAS OF MORNING LOW CLOUDS/FOG EXPECT SCATTERED MORNING COASTAL SHOWERS TO SHIFT INLAND WITH ISOLATED AFTERNOON THUNDERSTORMS POSSIBLE. A NE LOW LEVEL FLOW WILL PERSIST WITH STRONG HIGH PRESSURE CENTER MOVING OFF THE NEW ENGLAND COAST AND A WEAK SURFACE LOW DRIFTING INTO THE GULF...NORTH OF THE YUCATAN PENINSULA. HIGH CLOUDINESS WILL INCREASE WHICH WILL LIKELY RESULT IN HIGH TEMPERATURES A COUPLE OF DEGREES LOWER THAN TODAYS. HIGH SHOULD BE MOSTLY IN THE LOW TO MID 80S. MODELS SHOW SURGE OF TROPICAL MOISTURE STARTING TO MOVE INTO THE FL PANHANDLE AND SUWANNEE VALLEY SUNDAY NIGHT. THUS POPS WILL BE HIGHER OVER OUR WESTERN COUNTIES. MONDAY AND TUESDAY...MODELS CONTINUE TO SHOW DEEP TROPICAL MOISTURE SPREADING ACROSS THE AREA MONDAY AND TUESDAY. BOTH GFS AND ECMWF SHOW PWATS REACHING NEAR 2.5" WHICH IS MUCH ABOVE NORMAL. THIS WILL LIKELY PRODUCE AREAS OF HEAVY RAINFALL ENHANCED BY UPPER IMPULSES IN SW FLOW ALOFT. UNCERTAINTY STILL EVIDENT IN TRACK OF SURFACE LOW WITH GFS/GFS ENSEMBLE MOVING LOW INTO THE FL PANHANDLE ON TUESDAY AND THEN ACROSS S GA TUESDAY NIGHT. ECMWF SHOWS A TRACK FURTHER SOUTH...WITH THE LOW MOVING ACROSS NE FL WITH HIGHER QPF VALUES FOR NE FL. .LONG TERM...WEDNESDAY THROUGH SATURDAY...UPPER LOW OVER THE WESTERN GULF WEAKENS AND OPENS UP AS IT PHASES WITH A NORTHERN STREAM TROUGH ON WEDNESDAY. DRIER AIR IN THE MID AND UPPER LEVELS WILL SPREAD INTO THE AREA DECREASING THE HEAVY RAINFALL CHANCES. ANOTHER STRONG SURFACE HIGH WILL BUILD DOWN THE EAST COAST FRIDAY AND SATURDAY WITH INCREASING ONSHORE WINDS AND A CONTINUING CHANCE OF SHOWERS. TEMPERATURES WILL BE AT OR SLIGHTLY BELOW AVERAGE WITH RAIN CHANCES RETURNING TO NEAR NORMAL. && .AVIATION...OCNL MVFR CIGS EXPECTED THROUGH THE AFTN WITH A FEW SHOWERS POSSIBLE. VFR EXPECTED THIS EVENING ...WITH LOW CIGS EXPECTED LATE TONIGHT. CIGS EXPECTED TO LOWER INTO IFR AND POSSIBLY INTO LIFR CATEGORY AFTER 06Z...WITH HIGHEST PROBABILITIES AROUND THE 09Z-13Z TIME FRAME. CIGS SHOULD LIFT TO MVFR BY 14Z/15Z SUNDAY. && .MARINE...E TO NE WINDS AOB 15 KT EXPECTED THROUGH SUNDAY WITH SEAS GENERALLY IN THE 3-4 FT RANGE. WINDS WILL SLACKEN THROUGH BY MONDAY AS PRES GRADIENT RELAXES. WIND DIRECTION VEERS MONDAY AND TUESDAY AS THE WEDGE BEGINS TO SHIFT EAST AND LOW PRESSURE FORMS IN THE GULF OF MEXICO. RIP CURRENTS: MODERATE RISK THROUGH SUNDAY DUE TO ONSHORE WINDS AND SURF AROUND THE 3 FT RANGE. COASTAL IMPACTS: ISSUING A COASTAL FLOOD ADVISORY FOR THIS EVENING HIGH TIDE AND ONSHORE WINDS. BASED ON GUIDANCE...WE SHOULD JUST TOUCH MINOR FLOODING CRITERIA. WE HAVE DECIDED TO EXTEND THIS ADVISORY THROUGH LATE SUNDAY DUE TO UPCOMING FULL MOON AND PERSISTENT ONSHORE WINDS. && .PRELIMINARY POINT TEMPS/POPS... AMG 69 84 70 83 / 30 40 20 60 SSI 72 79 72 79 / 30 30 30 50 JAX 72 82 73 83 / 30 40 20 60 SGJ 75 81 73 82 / 30 40 30 50 GNV 71 85 71 84 / 30 50 30 60 OCF 72 87 72 86 / 40 50 40 60 && .JAX WATCHES/WARNINGS/ADVISORIES... FL...COASTAL FLOOD ADVISORY UNTIL 2 AM EDT MONDAY FOR COASTAL DUVAL- COASTAL NASSAU-FLAGLER-INLAND DUVAL-INLAND NASSAU-ST. JOHNS. GA...COASTAL FLOOD ADVISORY UNTIL 2 AM EDT MONDAY FOR COASTAL CAMDEN- COASTAL GLYNN-INLAND CAMDEN-INLAND GLYNN. AM...NONE. && $$ SHASHY/ZIBURA/GUILLET
AREA FORECAST DISCUSSION
NWS MIAMI FL
156 PM EDT SAT SEP 26 2015 .AVIATION... FOR THE SHORT TERM...TERMINAL KOPF IS CURRENTLY BEING AFFECTED BY A THUNDERSTORM WITH BRIEF PERIODS OF NEAR MVFR CONDITIONS POSSIBLE. OTHERWISE...SHOWERS AND ISOLATED THUNDERSTORMS ARE FORMING ALONG THE WEST AND EAST COAST SEA BREEZES WITH SHOWERS AND/OR THUNDERSTORMS IN THE VICINITY OF MOST OF THE TERMINALS...MAINLY FROM THE INTERIOR REGIONS. MOST OF THE ACTIVITY THIS AFTERNOON AND EARLY EVENING IS STILL EXPECTED TO BE INLAND BUT IN THE VICINITY OF THE TERMINALS...WITH ALL TERMINALS ASSIGNED VCTS AROUND THE 18Z TIME FRAME. WITH ANY SHOWERS OR A THUNDERSTORM BRIEF PERIODS OF MVFR TO NEAR IFR CONDITIONS ARE POSSIBLE. 60 && .PREV DISCUSSION... /ISSUED 1120 AM EDT SAT SEP 26 2015/ UPDATE... WHILE THE 12Z SOUNDING INDICATED CONSIDERABLE MOISTURE ACROSS THE REGION...WITH THE PWAT AT TWO INCHES...OTHERWISE THERE ARE RELATIVELY POOR LAPSE RATES AND WARMER MID-LEVELS. SO WHILE THUNDERSTORMS STILL EXPECTED THIS AFTERNOON...THE CURRENT FORECAST IS IN GENERAL AGREEMENT WITH THE RECENT MESO-SCALE MODELS INDICATING MOST OF THE CONVECTION EXPECTED TO BE IN THE INTERIOR REGIONS OF THE PENINSULA THIS AFTERNOON AND EARLY EVENING. THE MAIN EXPECTED IMPACT WILL BE LIGHTNING STRIKES. CONDITIONS APPEAR TO BE FAVORABLE FOR WATERSPOUTS ACROSS THE REGIONAL WATERS...BUT SO FAR THIS MORNING HAVE NOT RECEIVED ANY REPORTS ON ANY OCCURRENCE OF WATERSPOUTS. CONTINUE TO RECEIVE REPORTS OF MINOR COASTAL FLOODING ACROSS SOUTH FLORIDA...WITH REPORTS FROM NAPLES...MIAMI BEACH AND MATHESON PARK ALL REPORTING MINOR FLOODING. THIS IS CONSISTENT WITH REGIONAL OBSERVATIONS INDICATING OBSERVED WATER LEVELS HIGHER THAN PREDICTED LEVELS...WITH CURRENT VALUES AT VIRGINIA KEY ABOUT ONE FOOT ABOVE PREDICTED LEVELS WITH NAPLES CURRENTLY ABOUT THREE QUARTERS OF A FOOT ABOVE. THERE CONTINUES TO BE A COASTAL FLOOD STATEMENT IN EFFECT FOR ALL SOUTH FLORIDA COASTAL ZONES WITH MINOR COASTAL FLOODING POSSIBLE NEAR HIGH TIDES THROUGH MONDAY DUE TO HIGH ASTRONOMICAL TIDES. 60 PREV DISCUSSION... /ISSUED 744 AM EDT SAT SEP 26 2015/ AVIATION... DURING THE MORNING HOURS ALL THE EAST COAST TAF SITES WILL HAVE VCSH FOR PERIODS...BUT MAINLY VFR CONDITIONS EXPECTED ALL SOUTH FLORIDA TERMINALS DURING THE MORNING HOURS. LIGHT EASTERLY WINDS WILL PREVAIL ACROSS THE REGION WITH BOTH THE EAST AND WEST COAST SEA BREEZES EXPECTED TODAY...WITH MOST SHOWER/THUNDERSTORM ACTIVITY EXPECTED IN THE INTERIOR REGIONS. HOWEVER...ALL TERMINALS ASSIGNED VCTS AT 18Z WITH MORE ACTIVE CONVECTION INITIATING AROUND THAT TIME. BRIEF PERIODS OF MVFR TO NEAR IFR CONDITIONS POSSIBLE THIS AFTERNOON WITH OCCURRENCE OF ANY THUNDERSTORMS...BUT CONVECTION MAINLY EXPECTED INTERIOR REGIONS. 60 PREV DISCUSSION... /ISSUED 422 AM EDT SAT SEP 26 2015/ DISCUSSION... WATER VAPOR IMAGERY SHOWS A TROUGH ACROSS THE WESTERN GULF OF MEXICO WITH WEAK RIDGING FURTHER EAST. THIS PATTERN WILL HOLD AS GFS AND ECMWF BOTH SHOW THE TROUGH CUTTING OFF AND REMAINING NEAR THE TEXAS COAST INTO EARLY NEXT WEEK. MEANWHILE...SURFACE LOW PRESSURE DEVELOPMENT IS POSSIBLE OVER THE GULF...THOUGH ONLY A SLIGHT CHANCE OF TROPICAL DEVELOPMENT PER NHC DUE TO UNFAVORABLE UPPER LEVEL WINDS. EITHER WAY...MODEL CONSENSUS KEEPS THIS LOW WELL WEST OF SOUTH FLORIDA. DEEPEST MOISTURE REMAINS OVER THE GULF OF MEXICO. HOWEVER, IT STILL WILL BE RATHER MOIST LOCALLY ON A PREVAILING EAST TO SOUTHEAST WIND FLOW. THIS WILL FAVOR AFTERNOON CONVECTION OVER THE INTERIOR AND TOWARDS THE GULF COAST WITH LESSER CHANCES ALONG THE ATLANTIC COAST. LIKE THE HRRR SOLUTION TODAY WITH CONVECTION FAVORING THE EAST COAST THIS MORNING (THOUGH NOT EXPECTED TO BE TOO ACTIVE) BEFORE DEVELOPING/TRANSITIONING FURTHER INLAND. SO CUT POPS DOWN FOR THE ATLANTIC COAST THIS AFTERNOON AS COMPARED TO THE MODEL BLEND OUTPUT. LAPSE RATES REMAIN POOR AS WARMING OCCURS IN THE MID LEVELS...SO THE MAIN TSTORM IMPACT TODAY...AND THE NEXT FEW DAYS FOR THAT MATTER...WILL BE LIGHTNING STRIKES. BY MID-LATE NEXT WEEK...THE CUT OFF LOW LOOKS TO OPEN UP AND HEAD EAST. GFS IS WEAKER WITH THE TROUGH AND FURTHER NORTH WITH MORE RIDGING ACROSS SOUTH FL WHILE THE ECMWF HAS A SHARPER TROUGH ACROSS NORTH FL INTO THE EASTERN GULF OF MEXICO WITH MORE CONVECTION ACROSS SOUTH FL. SO THE PATTERN FOR THE EXTENDED PERIOD IS UNCERTAIN. TIDES ACROSS SOUTH FL ARE CURRENTLY RUNNING 0.8 FEET ABOVE PREDICTED. MINOR TIDAL FLOODING WAS OBSERVED AT NAPLES AND MIAMI BEACH YESTERDAY...AND AS TIDES RISE TOWARDS A PEAK MONDAY MORNING...ADDITIONAL TIDAL FLOODING IS ALMOST CERTAIN IN THE TYPICALLY PRONE AREAS AT EACH TIDE CYCLE. THE NEXT HIGH TIDES FOR THE ATLANTIC COAST IS NEAR SUNRISE THEN BETWEEN 7-8 PM THIS EVENING. FOR NAPLES THE NEXT HIGH TIDE IS AT AROUND NOON TIME THEN SHORTLY AFTER MIDNIGHT TONIGHT. /GREGORIA MARINE... AN EASTERLY WIND FLOW WILL CONTINUE...PREVAILING AT 5-10 KT THEN INCREASING JUST A TAD EARLY NEXT WEEK. SEAS WILL PREVAIL AT 4 FT OR LESS WITH A SMALL NORTH SWELL ATLANTIC WATERS. A SOMEWHAT LARGER SWELL ARRIVES MONDAY ACROSS THE ATLANTIC WATERS, ESPECIALLY OFF PALM BEACH COUNTY WITH WAVES PERHAPS TO 5 FT, WITH AREA OF LOW PRESSURE OFF THE CAROLINA COAST. SURFACE WINDS MAY VEER SOMEWHAT INTO EARLY NEXT WEEK. && .PRELIMINARY POINT TEMPS/POPS... WEST PALM BEACH 76 89 77 89 / 20 30 20 30 FORT LAUDERDALE 78 89 78 88 / 20 30 20 30 MIAMI 78 89 78 90 / 20 30 20 40 NAPLES 76 91 76 90 / 40 40 30 30 && .MFL WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. GM...NONE. && $$ SHORT TERM...10/CD LONG TERM....10/CD AVIATION...60/BD
AREA FORECAST DISCUSSION
NWS MIAMI FL
1120 AM EDT SAT SEP 26 2015 .UPDATE... WHILE THE 12Z SOUNDING INDICATED CONSIDERABLE MOISTURE ACROSS THE REGION...WITH THE PWAT AT TWO INCHES...OTHERWISE THERE ARE RELATIVELY POOR LAPSE RATES AND WARMER MID-LEVELS. SO WHILE THUNDERSTORMS STILL EXPECTED THIS AFTERNOON...THE CURRENT FORECAST IS IN GENERAL AGREEMENT WITH THE RECENT MESO-SCALE MODELS INDICATING MOST OF THE CONVECTION EXPECTED TO BE IN THE INTERIOR REGIONS OF THE PENINSULA THIS AFTERNOON AND EARLY EVENING. THE MAIN EXPECTED IMPACT WILL BE LIGHTNING STRIKES. CONDITIONS APPEAR TO BE FAVORABLE FOR WATERSPOUTS ACROSS THE REGIONAL WATERS...BUT SO FAR THIS MORNING HAVE NOT RECEIVED ANY REPORTS ON ANY OCCURRENCE OF WATERSPOUTS. CONTINUE TO RECEIVE REPORTS OF MINOR COASTAL FLOODING ACROSS SOUTH FLORIDA...WITH REPORTS FROM NAPLES...MIAMI BEACH AND MATHESON PARK ALL REPORTING MINOR FLOODING. THIS IS CONSISTENT WITH REGIONAL OBSERVATIONS INDICATING OBSERVED WATER LEVELS HIGHER THAN PREDICTED LEVELS...WITH CURRENT VALUES AT VIRGINIA KEY ABOUT ONE FOOT ABOVE PREDICTED LEVELS WITH NAPLES CURRENTLY ABOUT THREE QUARTERS OF A FOOT ABOVE. THERE CONTINUES TO BE A COASTAL FLOOD STATEMENT IN EFFECT FOR ALL SOUTH FLORIDA COASTAL ZONES WITH MINOR COASTAL FLOODING POSSIBLE NEAR HIGH TIDES THROUGH MONDAY DUE TO HIGH ASTRONOMICAL TIDES. 60 && .PREV DISCUSSION... /ISSUED 744 AM EDT SAT SEP 26 2015/ AVIATION... DURING THE MORNING HOURS ALL THE EAST COAST TAF SITES WILL HAVE VCSH FOR PERIODS...BUT MAINLY VFR CONDITIONS EXPECTED ALL SOUTH FLORIDA TERMINALS DURING THE MORNING HOURS. LIGHT EASTERLY WINDS WILL PREVAIL ACROSS THE REGION WITH BOTH THE EAST AND WEST COAST SEA BREEZES EXPECTED TODAY...WITH MOST SHOWER/THUNDERSTORM ACTIVITY EXPECTED IN THE INTERIOR REGIONS. HOWEVER...ALL TERMINALS ASSIGNED VCTS AT 18Z WITH MORE ACTIVE CONVECTION INITIATING AROUND THAT TIME. BRIEF PERIODS OF MVFR TO NEAR IFR CONDITIONS POSSIBLE THIS AFTERNOON WITH OCCURRENCE OF ANY THUNDERSTORMS...BUT CONVECTION MAINLY EXPECTED INTERIOR REGIONS. 60 PREV DISCUSSION... /ISSUED 422 AM EDT SAT SEP 26 2015/ DISCUSSION... WATER VAPOR IMAGERY SHOWS A TROUGH ACROSS THE WESTERN GULF OF MEXICO WITH WEAK RIDGING FURTHER EAST. THIS PATTERN WILL HOLD AS GFS AND ECMWF BOTH SHOW THE TROUGH CUTTING OFF AND REMAINING NEAR THE TEXAS COAST INTO EARLY NEXT WEEK. MEANWHILE...SURFACE LOW PRESSURE DEVELOPMENT IS POSSIBLE OVER THE GULF...THOUGH ONLY A SLIGHT CHANCE OF TROPICAL DEVELOPMENT PER NHC DUE TO UNFAVORABLE UPPER LEVEL WINDS. EITHER WAY...MODEL CONSENSUS KEEPS THIS LOW WELL WEST OF SOUTH FLORIDA. DEEPEST MOISTURE REMAINS OVER THE GULF OF MEXICO. HOWEVER, IT STILL WILL BE RATHER MOIST LOCALLY ON A PREVAILING EAST TO SOUTHEAST WIND FLOW. THIS WILL FAVOR AFTERNOON CONVECTION OVER THE INTERIOR AND TOWARDS THE GULF COAST WITH LESSER CHANCES ALONG THE ATLANTIC COAST. LIKE THE HRRR SOLUTION TODAY WITH CONVECTION FAVORING THE EAST COAST THIS MORNING (THOUGH NOT EXPECTED TO BE TOO ACTIVE) BEFORE DEVELOPING/TRANSITIONING FURTHER INLAND. SO CUT POPS DOWN FOR THE ATLANTIC COAST THIS AFTERNOON AS COMPARED TO THE MODEL BLEND OUTPUT. LAPSE RATES REMAIN POOR AS WARMING OCCURS IN THE MID LEVELS...SO THE MAIN TSTORM IMPACT TODAY...AND THE NEXT FEW DAYS FOR THAT MATTER...WILL BE LIGHTNING STRIKES. BY MID-LATE NEXT WEEK...THE CUT OFF LOW LOOKS TO OPEN UP AND HEAD EAST. GFS IS WEAKER WITH THE TROUGH AND FURTHER NORTH WITH MORE RIDGING ACROSS SOUTH FL WHILE THE ECMWF HAS A SHARPER TROUGH ACROSS NORTH FL INTO THE EASTERN GULF OF MEXICO WITH MORE CONVECTION ACROSS SOUTH FL. SO THE PATTERN FOR THE EXTENDED PERIOD IS UNCERTAIN. TIDES ACROSS SOUTH FL ARE CURRENTLY RUNNING 0.8 FEET ABOVE PREDICTED. MINOR TIDAL FLOODING WAS OBSERVED AT NAPLES AND MIAMI BEACH YESTERDAY...AND AS TIDES RISE TOWARDS A PEAK MONDAY MORNING...ADDITIONAL TIDAL FLOODING IS ALMOST CERTAIN IN THE TYPICALLY PRONE AREAS AT EACH TIDE CYCLE. THE NEXT HIGH TIDES FOR THE ATLANTIC COAST IS NEAR SUNRISE THEN BETWEEN 7-8 PM THIS EVENING. FOR NAPLES THE NEXT HIGH TIDE IS AT AROUND NOON TIME THEN SHORTLY AFTER MIDNIGHT TONIGHT. /GREGORIA MARINE... AN EASTERLY WIND FLOW WILL CONTINUE...PREVAILING AT 5-10 KT THEN INCREASING JUST A TAD EARLY NEXT WEEK. SEAS WILL PREVAIL AT 4 FT OR LESS WITH A SMALL NORTH SWELL ATLANTIC WATERS. A SOMEWHAT LARGER SWELL ARRIVES MONDAY ACROSS THE ATLANTIC WATERS, ESPECIALLY OFF PALM BEACH COUNTY WITH WAVES PERHAPS TO 5 FT, WITH AREA OF LOW PRESSURE OFF THE CAROLINA COAST. SURFACE WINDS MAY VEER SOMEWHAT INTO EARLY NEXT WEEK. && .PRELIMINARY POINT TEMPS/POPS... WEST PALM BEACH 89 76 89 77 / 30 20 30 20 FORT LAUDERDALE 89 78 89 78 / 20 20 30 20 MIAMI 90 78 89 78 / 30 20 30 20 NAPLES 90 76 91 76 / 40 40 40 30 && .MFL WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. GM...NONE. && $$ SHORT TERM...60/BD LONG TERM....60/BD
AREA FORECAST DISCUSSION
NWS MIAMI FL
744 AM EDT SAT SEP 26 2015 .AVIATION... DURING THE MORNING HOURS ALL THE EAST COAST TAF SITES WILL HAVE VCSH FOR PERIODS...BUT MAINLY VFR CONDITIONS EXPECTED ALL SOUTH FLORIDA TERMINALS DURING THE MORNING HOURS. LIGHT EASTERLY WINDS WILL PREVAIL ACROSS THE REGION WITH BOTH THE EAST AND WEST COAST SEA BREEZES EXPECTED TODAY...WITH MOST SHOWER/THUNDERSTORM ACTIVITY EXPECTED IN THE INTERIOR REGIONS. HOWEVER...ALL TERMINALS ASSIGNED VCTS AT 18Z WITH MORE ACTIVE CONVECTION INITIATING AROUND THAT TIME. BRIEF PERIODS OF MVFR TO NEAR IFR CONDITIONS POSSIBLE THIS AFTERNOON WITH OCCURRENCE OF ANY THUNDERSTORMS...BUT CONVECTION MAINLY EXPECTED INTERIOR REGIONS. 60 && .PREV DISCUSSION... /ISSUED 422 AM EDT SAT SEP 26 2015/ DISCUSSION... WATER VAPOR IMAGERY SHOWS A TROUGH ACROSS THE WESTERN GULF OF MEXICO WITH WEAK RIDGING FURTHER EAST. THIS PATTERN WILL HOLD AS GFS AND ECMWF BOTH SHOW THE TROUGH CUTTING OFF AND REMAINING NEAR THE TEXAS COAST INTO EARLY NEXT WEEK. MEANWHILE...SURFACE LOW PRESSURE DEVELOPMENT IS POSSIBLE OVER THE GULF...THOUGH ONLY A SLIGHT CHANCE OF TROPICAL DEVELOPMENT PER NHC DUE TO UNFAVORABLE UPPER LEVEL WINDS. EITHER WAY...MODEL CONSENSUS KEEPS THIS LOW WELL WEST OF SOUTH FLORIDA. DEEPEST MOISTURE REMAINS OVER THE GULF OF MEXICO. HOWEVER, IT STILL WILL BE RATHER MOIST LOCALLY ON A PREVAILING EAST TO SOUTHEAST WIND FLOW. THIS WILL FAVOR AFTERNOON CONVECTION OVER THE INTERIOR AND TOWARDS THE GULF COAST WITH LESSER CHANCES ALONG THE ATLANTIC COAST. LIKE THE HRRR SOLUTION TODAY WITH CONVECTION FAVORING THE EAST COAST THIS MORNING (THOUGH NOT EXPECTED TO BE TOO ACTIVE) BEFORE DEVELOPING/TRANSITIONING FURTHER INLAND. SO CUT POPS DOWN FOR THE ATLANTIC COAST THIS AFTERNOON AS COMPARED TO THE MODEL BLEND OUTPUT. LAPSE RATES REMAIN POOR AS WARMING OCCURS IN THE MID LEVELS...SO THE MAIN TSTORM IMPACT TODAY...AND THE NEXT FEW DAYS FOR THAT MATTER...WILL BE LIGHTNING STRIKES. BY MID-LATE NEXT WEEK...THE CUT OFF LOW LOOKS TO OPEN UP AND HEAD EAST. GFS IS WEAKER WITH THE TROUGH AND FURTHER NORTH WITH MORE RIDGING ACROSS SOUTH FL WHILE THE ECMWF HAS A SHARPER TROUGH ACROSS NORTH FL INTO THE EASTERN GULF OF MEXICO WITH MORE CONVECTION ACROSS SOUTH FL. SO THE PATTERN FOR THE EXTENDED PERIOD IS UNCERTAIN. TIDES ACROSS SOUTH FL ARE CURRENTLY RUNNING 0.8 FEET ABOVE PREDICTED. MINOR TIDAL FLOODING WAS OBSERVED AT NAPLES AND MIAMI BEACH YESTERDAY...AND AS TIDES RISE TOWARDS A PEAK MONDAY MORNING...ADDITIONAL TIDAL FLOODING IS ALMOST CERTAIN IN THE TYPICALLY PRONE AREAS AT EACH TIDE CYCLE. THE NEXT HIGH TIDES FOR THE ATLANTIC COAST IS NEAR SUNRISE THEN BETWEEN 7-8 PM THIS EVENING. FOR NAPLES THE NEXT HIGH TIDE IS AT AROUND NOON TIME THEN SHORTLY AFTER MIDNIGHT TONIGHT. /GREGORIA MARINE... AN EASTERLY WIND FLOW WILL CONTINUE...PREVAILING AT 5-10 KT THEN INCREASING JUST A TAD EARLY NEXT WEEK. SEAS WILL PREVAIL AT 4 FT OR LESS WITH A SMALL NORTH SWELL ATLANTIC WATERS. A SOMEWHAT LARGER SWELL ARRIVES MONDAY ACROSS THE ATLANTIC WATERS, ESPECIALLY OFF PALM BEACH COUNTY WITH WAVES PERHAPS TO 5 FT, WITH AREA OF LOW PRESSURE OFF THE CAROLINA COAST. SURFACE WINDS MAY VEER SOMEWHAT INTO EARLY NEXT WEEK. && .PRELIMINARY POINT TEMPS/POPS... WEST PALM BEACH 89 76 89 77 / 30 20 30 20 FORT LAUDERDALE 89 78 89 78 / 20 20 30 20 MIAMI 90 78 89 78 / 30 20 30 20 NAPLES 90 76 91 76 / 40 40 40 30 && .MFL WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. GM...NONE. && $$ SHORT TERM...60/BD LONG TERM....60/BD AVIATION...60/BD
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
529 AM EDT SAT SEP 26 2015 .SYNOPSIS... 09Z WATER VAPOR AND H4 RAP ANALYSIS SHOWING NORTHERN STREAM FLOW CONTAINED WELL ALONG OR TO THE NORTH OF THE CANADIAN BORDER AS IT MOVES UP AND OVER A STRONG MID/UPPER RIDGE IN PLACE FROM THE DESERT SOUTHWEST TO THE NORTHERN PLAINS. FURTHER SOUTH AND EAST FROM THIS RIDGE WE FIND AN UNPROGRESSIVE...BROAD...BUT DEEP UPPER TROUGH COVERING MUCH OF THE CENTRAL AND EASTERN CONUS. SEVERAL UPPER LOWS CAN BE SEEN IN WATER VAPOR IMAGERY WITHIN THE LARGER SCALE TROUGH. ONE IS LIFTING NORTH THROUGH THE TN/OH VALLEYS...WHILE ANOTHER IS SPINNING OVER THE WESTERN GULF OF MEXICO. OUR FORECAST AREA RESIDES WITHIN THE DEEP SOUTH TO SOUTHWEST FLOW ON THE EASTERN PERIPHERY OF THIS UPPER LOW/TROUGH. WV IMAGERY IS SHOWS ABUNDANT DEEP ATMOSPHERIC MOISTURE LIFTING NORTH WITH THIS FLOW OVER THE CENTRAL/EASTERN GULF. AT THE SURFACE...THE FLORIDA PENINSULA RESIDES WITHIN A WEAK PRESSURE GRADIENT BETWEEN HIGH PRESSURE RIDGING DOWN THE SPINE OF THE APPALACHIANS...AND A WEAK SURFACE TROUGH/LOW OVER THE SOUTH- CENTRAL GULF OF MEXICO. THE RESULTING FLOW IS LIGHT FROM THE EAST AND SOUTHEAST...AND OTHER THAN WEAK SEA-BREEZE CIRCULATIONS NEAR THE COAST EACH AFTERNOON...WILL BE THE PREVAILING FLOW ACROSS THE REGION THROUGH THE WEEKEND. REGIONAL RADARS SHOW A FEW ISOLATED CONVECTIVE CELLS WELL OFFSHORE THIS MORNING. MAY SEE A BIT OF A INCREASE IN ACTIVITY TOWARD DAWN AS THE NOCTURNAL LAND BREEZE MAXIMIZES...FOLLOWED BY A GRADUAL DECREASE INTO THE LATE MORNING HOURS. THERE ARE SOME PATCHES OF FOG OUT THERE THIS MORNING...MAINLY TO THE NORTH OF THE I-4 CORRIDOR. && .SHORT TERM (TODAY THROUGH SUNDAY)... A GENERALLY BENIGN FORECAST FOR THE MORNING HOURS...OTHER THAN SOME PATCHY FOG OVER THE NORTHERN HALF OF THE AREA FOR THE FIRST HOUR OR TWO OF DAYLIGHT. THINGS SEEM TO BE ALIGNING FOR A RATHER ACTIVE AFTERNOON/EVENING IN TERMS OF CONVECTION...ESPECIALLY FOR LATE SEPTEMBER. THERE ARE SEVERAL FAVORABLE THINGS IN PLACE. FIRST IS THE LOW LEVEL FLOW REGIME. THE 1000-700MB MEAN FLOW IS LIGHT FROM THE SOUTHEAST. THIS FLOW IS GENERALLY OUR MOST ACTIVE ALONG THE WESTERN HALF OF THE FL PENINSULA DURING THE WARM SEASON SEA- BREEZE THUNDERSTORM MONTHS DUE TO ITS CONVERGENT FOCUS WITH THE WEST COAST SEA-BREEZE. IN ADDITION TO THIS FAVORABLE WIND PATTERN...THERE IS ABUNDANT COLUMN MOISTURE IN PLACE. WHILE THE DEEP MOISTURE TENDS TO LOWER THE POTENTIAL FOR STRONG STORMS...IT INCREASES THE OVERALL COVERAGE AND POTENTIAL FOR HEAVY RAINFALL. EXPECT TO SEE THE FIRST STORMS DEVELOP AROUND MIDDAY NEAR THE COAST WITH THE INITIAL SEA-BREEZE...THEN EXPECT NUMEROUS ADDITIONAL STORMS TO EXPAND INLAND AS NEW AND OLD OUTFLOW BOUNDARIES TAKE OVER THE STORM EVOLUTION. RAIN CHANCES OVER MUCH OF THE AREA ARE ABOVE CLIMO FOR LATE SEPTEMBER. STORMS MAY BRIEFLY MAXIMIZE LATE IN THE AFTERNOON/EARLY EVENING AWAY FROM THE COAST...BUT SIMILAR TO PREVIOUS DAYS...IT IS LIKELY THAT WE WILL SEE A SECOND PUSH OF ACTIVITY BACK TOWARD THE COAST THIS EVENING...AS THE SEA-BREEZE SHUTS DOWN AND THE PREVAILING FLOW BEGINS TO SHIFT OUTFLOW BOUNDARIES BACK TO THE WEST. CONVECTIVE ACTIVITY SHOULD GENERALLY END LATE IN THE EVENING...ALTHOUGH WITH DEEP MOISTURE IN PLACE...CAN NOT RULE OUT AN ACTIVE STORMS CLUSTER HOLDING TOGETHER INTO THE EARLY MORNING HOURS OF SUNDAY. OVERALL...THE MAJORITY OF THE STORMS AFTER MIDNIGHT WILL CERTAINLY HAVE SHIFTED OFFSHORE INTO THE GULF. DURING THE DAY ON SUNDAY WILL BE WATCHING A WEAK AREA OF LOW PRESSURE EMERGE INTO THE SOUTH- CENTRAL GULF AND BEGIN MOVING NORTH. THERE IS STILL SOME UNCERTAINTY IN THE EXACT EVOLUTION AND TRACK OF THIS LOW AS ITS IMPACT PERTAIN TO OUR FORECAST AREA...HOWEVER...ATMOSPHERIC CONDITIONS ARE NOT FAVORABLE FOR TROPICAL DEVELOPMENT. THE MORE LIKELY SCENARIO IS THAT A WEAK/SEMI-DISORGANIZED LOW WILL SHIFT NORTHWARD TOWARD THE NORTH-CENTRAL GULF COAST DURING THE EARLY PORTION OF NEXT WEEK. AS ALWAYS...WE WILL BE WATCHING CLOSELY IN CASE SOMETHING MORE SIGNIFICANT DEVELOPS. FOR THE DAYLIGHT HOURS OF SUNDAY...THIS LOW AND ANY POTENTIAL IMPACTS WILL STILL BE TOO FAR AWAY FOR DIRECT EFFECTS. WHAT WILL BE OCCURRING THOUGH IS A TIGHTENING OF THE GRADIENT OVER THE AREA. THIS STRONGER SYNOPTIC FLOW SHOULD GENERALLY PREVENT A STRONG SEA-BREEZE OR PIN THIS BOUNDARY AT THE COAST FOR THE AFTERNOON. THIS BEING SAID...AND COMBINED WITH CONTINUED DEEP MOISTURE...WOULD ANTICIPATE ANOTHER ACTIVE AFTERNOON/EVENING OF DIURNAL STORMS. EVEN WITHOUT OFFICIAL TROPICAL DEVELOPMENT OF THE GULF LOW...A TRACK CLOSE ENOUGH TO OUR AREA WOULD STILL POSE PROBLEMS WITH THE POTENTIAL FOR HEAVY RAIN BANDS BY MONDAY. SOME GUIDANCE IS SUGGESTING THIS POTENTIAL...WHILE OTHERS KEEP THE HEAVIER RAIN OFFSHORE. WILL JUST HAVE TO WAIT AND SEE. NUMERICAL GUIDANCE SHOULD GET A BETTER HANDLE ON THE LOW ONCE THE FEATURE EMERGES INTO THE GULF OF MEXICO ON SUNDAY. && .LONG TERM (MONDAY THROUGH NEXT FRIDAY)... PERIOD WILL BEGIN WITH A STRONG U/L CUT- OFF LOW OVER THE NORTHWEST GULF OF MEXICO. THIS WILL INDUCE A SURFACE LOW TO DEVELOP OVER THE GULF HOWEVER LOCATION OF THE MAIN SURFACE LOW REMAINS RATHER UNCERTAIN. U/L DIFFLUENCE ON THE EAST SIDE OF THE U/L TROUGH MAY CREATE A FAVORABLE AREA OVER THE NORTH CENTRAL GULF FOR LOW PRESSURE TO DEVELOP MONDAY NIGHT AND TUESDAY WITH A LARGE AREA OF SHOWERS AND THUNDERSTORMS DEVELOPING OVER THE EASTERN GULF OF MEXICO...AND ADVECTING LOCALLY OVER THE FORECAST AREA. THE U/L LOW IS EXPECTED TO OPEN UP AND LIFT OUT TO THE NORTHEAST WEDNESDAY WITH THE L/W TROUGH AXIS SLOWLY MOVING OVER THE FORECAST AREA THURSDAY AND FRIDAY WITH ADDITIONAL SHOWERS AND THUNDERSTORMS. GFS AND ECMWF IN FAIR AGREEMENT WITH THIS SCENARIO...WHICH WOULD LEAD TO A RATHER WET EXTENDED PERIOD. HOWEVER LEANING MORE TOWARD A SREF SOLUTION ATTM WHICH HAS A MORE VERTICALLY STACKED SYSTEM WITH THE SURFACE LOW DEVELOPING OVER THE NORTHWEST GULF OF MEXICO. WOULD EXPECT THE STRONG U/L CUT-OFF OVER THE NORTHWEST GULF TO INDUCE DOWNSTREAM U/L RIDGING OVER FLORIDA...WHICH IS DEPICTED BEST BY THE SREF. THIS WOULD INITIALLY DECREASE POPS OVER THE REGION MONDAY AND TUESDAY HOLDING THE AREA OF SHOWERS AND THUNDERSTORMS TO THE WEST POSSIBLY REACHING THE OFFSHORE WATERS. CHANCE OF SHOWERS AND THUNDERSTORMS WOULD INCREASE MID WEEK AS THE SYSTEM OPENS UP AND LIFTS OUT WITH SHOWERS AND THUNDERSTORMS PUSHING ACROSS THE REGION AHEAD OF THE L/W TROUGH WEDNESDAY THROUGH FRIDAY. DUE TO THE HIGH DEGREE OF UNCERTAINTY IN THE EVOLUTION OF THE SYSTEM OVER THE GULF...WILL KEEP LIKELY POPS IN THE FORECAST MONDAY AND TUESDAY. HOWEVER WILL GO BELOW GFS/ECMWF GUIDANCE. && .AVIATION... AREAS OF FOG AND LOWER CLOUDS HAVE BEEN DEVELOPING EARLY THIS MORNING...MAINLY NORTH OF THE I-4 CORRIDOR. WILL EXPECT SOME OF THESE CEILING RESTRICTIONS TO BUILD SOUTH IN THE FEW HOURS SURROUNDING DAWN...AND BRIEF IFR/MVFR CIGS ARE POSSIBLE AT KTPA/KLAL/KSRQ/KPIE BETWEEN 10-13Z. VFR CONDITIONS WILL RETURN BY MID MORNING...FOLLOWED BY SCT-NMRS THUNDERSTORMS DEVELOPMENT BEGINNING AROUND MIDDAY...PERSISTING THROUGH THE EARLY EVENING HOURS. ALL TERMINALS RUN A RISK OF A PASSING STORM AFTER 17Z. && .MARINE... THE FLORIDA PENINSULA WILL RESIDE BETWEEN HIGH PRESSURE TO OUR NORTH AND A WEAK AREA OF LOW PRESSURE OVER THE SOUTH-CENTRAL GULF OF MEXICO THROUGH THE WEEKEND. THIS PATTERN WILL PROVIDE A GENERAL EAST TO SOUTHEAST FLOW...ALTHOUGH WINDS MAY BRIEFLY SWITCH ONSHORE WITH SEA-BREEZE DEVELOPMENT BOTH SATURDAY AND SUNDAY AFTERNOONS. ONSHORE WINDS WILL QUICKLY SHIFT BACK OFFSHORE DURING THE EVENING HOURS EACH DAY. THE LOW IN THE SOUTHERN GULF IS FORECAST TO STAY WEAK AND DISORGANIZED AS IT MOVES NORTHWARD TOWARD THE NORTHERN GULF COAST MONDAY AND TUESDAY. AT THIS TIME...TROPICAL DEVELOPMENT IS NOT ANTICIPATED...HOWEVER...WINDS AND SEAS MAY REACH CAUTIONARY LEVELS AT TIMES EARLY NEXT WEEK. THERE WILL ALSO BE AN INCREASING CHANCE FOR MORE NUMEROUS SHOWERS AND STORMS OVER THE EASTERN GULF BY THE EARLY PORTION OF NEXT WEEK. && .FIRE WEATHER... THE FLORIDA PENINSULA WILL RESIDE BETWEEN HIGH PRESSURE TO OUR NORTH AND A WEAK AREA OF LOW PRESSURE OVER THE SOUTH-CENTRAL GULF OF MEXICO THROUGH THE WEEKEND. THIS PATTERN WILL PROVIDE A MOIST EAST TO SOUTHEAST FLOW ACROSS THE FORECAST AREA. DEEP TROPICAL MOISTURE WILL ALLOW FOR SCATTERED TO NUMEROUS AFTERNOON AND EVENING THUNDERSTORMS EACH DAY. THERE IS STILL SOME UNCERTAINTY IN THE EVOLUTION OF THE GULF LOW PRESSURE SYSTEM DURING THE MONDAY AND TUESDAY PERIOD. THERE IS SOME POTENTIAL FOR BANDS OF HEAVIER RAINFALL BY EARLY NEXT WEEK...ESPECIALLY CLOSE TO THE COAST. EITHER WAY... MOISTURE LEVELS WILL BE VERY HIGH...WITH RELATIVE HUMIDITY VALUES WELL ABOVE CRITICAL LEVELS THROUGH THE DURATION OF THE FORECAST PERIOD. FOG POTENTIAL...SOME PATCHY GROUND FOG WILL BE POSSIBLE OVER INLAND LOCATIONS SUNDAY MORNING...HOWEVER NO SIGNIFICANT FOG OR VISIBILITY RESTRICTIONS ARE EXPECTED. && .PRELIMINARY POINT TEMPS/POPS... TPA 89 75 89 76 / 60 50 60 50 FMY 90 75 91 76 / 40 40 60 50 GIF 90 74 90 75 / 50 40 50 40 SRQ 87 75 88 76 / 40 40 50 50 BKV 89 73 90 73 / 60 50 60 40 SPG 88 77 89 78 / 50 40 50 50 && .TBW WATCHES/WARNINGS/ADVISORIES... FL...NONE. GULF WATERS...NONE. && $$ SYNOPSIS/SHORT TERM/AVIATION/MARINE/FIRE WX...MROCZKA LONG TERM/DECISION SUPPORT...OGLESBY
AREA FORECAST DISCUSSION
NWS MIAMI FL
422 AM EDT SAT SEP 26 2015 .DISCUSSION... WATER VAPOR IMAGERY SHOWS A TROUGH ACROSS THE WESTERN GULF OF MEXICO WITH WEAK RIDGING FURTHER EAST. THIS PATTERN WILL HOLD AS GFS AND ECMWF BOTH SHOW THE TROUGH CUTTING OFF AND REMAINING NEAR THE TEXAS COAST INTO EARLY NEXT WEEK. MEANWHILE...SURFACE LOW PRESSURE DEVELOPMENT IS POSSIBLE OVER THE GULF...THOUGH ONLY A SLIGHT CHANCE OF TROPICAL DEVELOPMENT PER NHC DUE TO UNFAVORABLE UPPER LEVEL WINDS. EITHER WAY...MODEL CONSENSUS KEEPS THIS LOW WELL WEST OF SOUTH FLORIDA. DEEPEST MOISTURE REMAINS OVER THE GULF OF MEXICO. HOWEVER, IT STILL WILL BE RATHER MOIST LOCALLY ON A PREVAILING EAST TO SOUTHEAST WIND FLOW. THIS WILL FAVOR AFTERNOON CONVECTION OVER THE INTERIOR AND TOWARDS THE GULF COAST WITH LESSER CHANCES ALONG THE ATLANTIC COAST. LIKE THE HRRR SOLUTION TODAY WITH CONVECTION FAVORING THE EAST COAST THIS MORNING (THOUGH NOT EXPECTED TO BE TOO ACTIVE) BEFORE DEVELOPING/TRANSITIONING FURTHER INLAND. SO CUT POPS DOWN FOR THE ATLANTIC COAST THIS AFTERNOON AS COMPARED TO THE MODEL BLEND OUTPUT. LAPSE RATES REMAIN POOR AS WARMING OCCURS IN THE MID LEVELS...SO THE MAIN TSTORM IMPACT TODAY...AND THE NEXT FEW DAYS FOR THAT MATTER...WILL BE LIGHTNING STRIKES. BY MID-LATE NEXT WEEK...THE CUT OFF LOW LOOKS TO OPEN UP AND HEAD EAST. GFS IS WEAKER WITH THE TROUGH AND FURTHER NORTH WITH MORE RIDGING ACROSS SOUTH FL WHILE THE ECMWF HAS A SHARPER TROUGH ACROSS NORTH FL INTO THE EASTERN GULF OF MEXICO WITH MORE CONVECTION ACROSS SOUTH FL. SO THE PATTERN FOR THE EXTENDED PERIOD IS UNCERTAIN. TIDES ACROSS SOUTH FL ARE CURRENTLY RUNNING 0.8 FEET ABOVE PREDICTED. MINOR TIDAL FLOODING WAS OBSERVED AT NAPLES AND MIAMI BEACH YESTERDAY...AND AS TIDES RISE TOWARDS A PEAK MONDAY MORNING...ADDITIONAL TIDAL FLOODING IS ALMOST CERTAIN IN THE TYPICALLY PRONE AREAS AT EACH TIDE CYCLE. THE NEXT HIGH TIDES FOR THE ATLANTIC COAST IS NEAR SUNRISE THEN BETWEEN 7-8 PM THIS EVENING. FOR NAPLES THE NEXT HIGH TIDE IS AT AROUND NOON TIME THEN SHORTLY AFTER MIDNIGHT TONIGHT. /GREGORIA && .MARINE... AN EASTERLY WIND FLOW WILL CONTINUE...PREVAILING AT 5-10 KT THEN INCREASING JUST A TAD EARLY NEXT WEEK. SEAS WILL PREVAIL AT 4 FT OR LESS WITH A SMALL NORTH SWELL ATLANTIC WATERS. A SOMEWHAT LARGER SWELL ARRIVES MONDAY ACROSS THE ATLANTIC WATERS, ESPECIALLY OFF PALM BEACH COUNTY WITH WAVES PERHAPS TO 5 FT, WITH AREA OF LOW PRESSURE OFF THE CAROLINA COAST. SURFACE WINDS MAY VEER SOMEWHAT INTO EARLY NEXT WEEK. && .PRELIMINARY POINT TEMPS/POPS... WEST PALM BEACH 89 76 89 77 / 30 20 30 20 FORT LAUDERDALE 89 78 89 78 / 20 20 30 20 MIAMI 90 78 89 78 / 30 20 30 20 NAPLES 90 76 91 76 / 40 40 40 30 && .MFL WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. GM...NONE. && $$
AREA FORECAST DISCUSSION
NWS MIAMI FL
158 AM EDT SAT SEP 26 2015 .AVIATION... NOT MUCH CHANGE FROM YESTERDAY. LIGHT AND VARIABLE CONDITIONS THIS MORNING WILL ONCE AGAIN GIVE WAY TO EASTERLY WIND IN THE LATE MORNING TO EARLY AFTERNOON. CONVECTIVE SHOWERS AND STORMS WILL BEGIN TO DEVELOP IN THE EARLY AFTERNOON AS WELL. HAVE VCTS IN ALL TAFS TO REFLECT THIS. OTHERWISE VFR CONDITIONS THROUGH THE TAF PERIOD, WITH THE EXCEPTION OF BRIEF IFR UNDER ANY HEAVY SHOWERS. && .PREV DISCUSSION... /ISSUED 806 PM EDT FRI SEP 25 2015/ UPDATE... MOST SHOWERS AND THUNDERSTORMS HAVE DISSIPATED THIS EVENING. STILL THE POSSIBILITY FOR AN ISOLATED SHOWER OR STORM OVER THE NEXT FEW HOURS, CONSIDERING THE IMMEDIATE EAST COAST WAS UNTOUCHED THIS AFTERNOON. ONSHORE FLOW LATE TONIGHT AND NEAR DAWN CAN ONCE AGAIN PRODUCE SHOWERS MOVING ACROSS THE BEACHES, WHICH MAY LEAD WATER TO ISSUES ALONG MIAMI BEACH AGAIN, CONSIDERING HIGH TIDE IS AROUND 7AM. PREV DISCUSSION... /ISSUED 346 PM EDT FRI SEP 25 2015/ SHORT TERM (TONIGHT-MON NIGHT)... COASTAL FLOOD STATEMENT CONTINUES THROUGH MONDAY NIGHT, NOW FOR WEST AND EAST COASTS. ANY RAINFALL THIS WEEKEND, EVEN MORE SO AROUND HIGH TIDE, WILL EXACERBATE THE SITUATION. LESS HIGH CLOUDS TODAY, HAS ALLOWED FOR BETTER THUNDERSTORM DEVELOPMENT THIS AFTERNOON. THE EAST COAST SEA BREEZE HAS ALREADY PROGRESSED INLAND, SUCH THAT MOST ACTIVITY MAY BE OVER THE INTERIOR OR FAR WESTERN SUBURBS. WITH WEAK WIND PROFILE STILL IN PLACE, AND SHOWERS CURRENTLY DRIFTING TO THE NORTHEAST, HRRR SHOWS THE POSSIBILITY OF A FEW STORMS MOVING BACK TOWARDS THE METRO AND BEACHES INTO EARLY EVENING. THIS PROCESS MAY HAPPEN A LITTLE EARLIER THOUGH THROUGH PALM BEACH COUNTY, WITH MORE WESTERLY COMPONENT IN THE MEAN WIND/STORM MOTION THERE. HEAVY RAINFALL AGAIN APPEARS TO BE THE MAIN THREAT CONSIDERING MOVEMENT. MITIGATING FACTOR FOR ANY STRONGER STORMS TODAY WILL BE A NOTABLE MID LEVEL INVERSION FROM THIS MORNING`S RAOB. MODEL SOUNDING FORECASTED AFTERNOON CAPE ISN`T VERY IMPRESSIVE. TONIGHT-SATURDAY...AS PERSISTENT SURFACE TROUGH OVER CENTRAL FL CONTINUES TO WASH OUT, EASTERLY COMPONENT WILL BECOME SOMEWHAT DEEPER, ALTHOUGH SPEEDS WILL REMAIN RATHER LIGHT. SHOWERS AND A FEW STORMS WILL REMAIN POSSIBLE LATE NIGHT AND THROUGH THE MORNING HOURS. WITH SIMILAR PROGRESSION OF THE SEA BREEZE EXPECTED SATURDAY, MOST STORMS ARE EXPECTED TO BE INTERIOR AND OFF THE COAST INTO THE AFTERNOON HOURS. PERHAPS A SMALLER CHC OF ACTIVITY BLEEDING BACK TOWARDS THE EAST COAST THAN TODAY. INSTABILITY IS NOTHING TO GET EXCITED ABOUT WITH SIMILAR H7-H5 LAPSE RATES AND H5 TEMPS TO TODAY. IF MID LEVEL INVERSION FROM THIS MORNING`S SOUNDING REMAINS, THAT COULD RESTRICT ACTIVITY AGAIN. PWATS THOUGH REMAIN ABOVE 2" AND DEEP MOISTURE REMAINS. SUNDAY-MONDAY... EASTERLY FLOW TRIES TO BECOME A LITTLE DEEPER AND STRONGER, ALTHOUGH LARGE SURFACE HIGH MOVING OFF THE MID ATLANTIC COAST IS HAVING PROBLEMS EXERTING INFLUENCE, WITH WEAK LOW PRESSURE/SURFACE TROUGH STUCK ALONG THE CAROLINA COAST SUNDAY. H5 TEMP PERHAPS WARMS ABOVE -6C. FOCUS FOR AFTERNOON STORMS WILL CONTINUE TO BE INTERIOR, WITH COVERAGE INCREASING OVER THE WEST COAST ALSO. OPERATIONAL GFS CONTINUES TO BE THE MOST AGGRESSIVE WITH AREA OF LOW PRESSURE MOVING INTO THE WESTERN OR CENTRAL GULF OF MEXICO SUNDAY AND MONDAY. THE ECMWF IS A LITTLE FARTHER EAST THAN PREVIOUS RUNS, BUT CONTINUES WEAKER. NHC CONTINUES TO INDICATE A NOT PARTICULARLY FAVORABLE ENVIRONMENT FOR ANY DEVELOPMENT IN THEIR 5 DAY OUTLOOK AS THE AREA OF LOW PRESSURE POSSIBLY CONTINUES ON A NORTHERLY TRACK THROUGH THE GULF OF MEXICO AFTER IT CROSSES THE YUCATAN PENINSULA. AS THIS OCCURS, WINDS WILL VEER THROUGH THE COLUMN, BECOMING MORE SSE AT THE SURFACE AND SSW ALOFT. THUS, STORMS MAY BECOME MORE FAVORABLE ALONG THE EAST COAST WITH THE CHANGE IN WIND DIRECTION. HOWEVER, WITH AN H5 RIDGE STRETCHING FURTHER ACROSS THE WESTERN ATLANTIC THAN THIS WEEKEND, H5 TEMPS CONTINUE TO WARM WITH RATHER UNFAVORABLE MID LEVEL LAPSE RATES. MODEL/BLENDED POPS MAY BE DRIVEN BY THE DEEP MOIST SOUTHERLY FLOW EVOLVING AT ALL LEVELS, THAN TYPICAL AFTERNOON THUNDERSTORMS. LONG TERM (TUE-FRI)... WE WILL STILL NEED TO WATCH MOVEMENT OF LOW PRESSURE AND HOW FAR EAST DEEP TROPICAL MOISTURE AND HEAVY RAINFALL SPREADS TOWARDS OUR GULF COAST REGION, ALTHOUGH CURRENT GUIDANCE POSSIBLY HAS THE LOW STAYING WELL NORTH AND WEST OF SOUTH FLORIDA. CLOSED MID AND UPPER LEVEL LOW OVER TX/LA EARLY NEXT WEEK, OPENS UP AS A TROUGH MOVES TOWARDS THE EASTERN SEABOARD TOWARDS THE MIDDLE AND END OF NEXT WEEK. ECMWF/GFS DIFFER ON THE DEPTH AND STRENGTH OF THIS TROUGH. THE GFS ACTUALLY HAS A GOOD CHUNK OF MID LEVEL DRY AIR ARRIVING INTO WEDNESDAY, ASSOCIATED WITH STRONGER RIDGING AND SUBSIDENCE OVER SOUTH FLORIDA. THIS MAY MITIGATE A WIND FIELD WHICH MAY BECOME MORE FAVORABLE FOR STORMS FOCUSED THROUGH THE INTERIOR AND EAST COAST PER THE DEEPER ECMWF LATE NEXT WEEK. MARINE... AN EASTERLY WIND FLOW WILL CONTINUE...PREVAILING AT 5-10 KT THEN INCREASING JUST A TAD EARLY NEXT WEEK. SEAS WILL PREVAIL AT 4 FT OR LESS WITH A SMALL NORTH SWELL ATLANTIC WATERS. A SOMEWHAT LARGER SWELL ARRIVES MONDAY ACROSS THE ATLANTIC WATERS, ESPECIALLY OFF PALM BEACH COUNTY WITH WAVES PERHAPS TO 5 FT, WITH AREA OF LOW PRESSURE OFF THE CAROLINA COAST. SURFACE WINDS MAY VEER SOMEWHAT INTO EARLY NEXT WEEK. && .PRELIMINARY POINT TEMPS/POPS... WEST PALM BEACH 89 77 89 77 / 40 20 40 20 FORT LAUDERDALE 88 78 89 79 / 30 20 30 20 MIAMI 90 78 90 78 / 50 20 40 20 NAPLES 90 76 90 76 / 40 20 50 30 && .MFL WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. GM...NONE. && $$ SHORT TERM...21/KM LONG TERM....21/KM AVIATION...13/SI
AREA FORECAST DISCUSSION
NWS BOISE ID
924 AM MDT SAT SEP 26 2015 .DISCUSSION...FORECAST WAS UPDATED TO REMOVE THUNDERSTORMS IN OUR REGION THIS MORNING. OVERNIGHT SHOWERS ATTEMPTED TO BECOME CONVECTIVE AROUND 4 AM MDT BUT QUICKLY LOST STRENGTH. SHOWERS SHOULD CONTINUE FOR THE NEXT HOUR...ENDING MID-MORNING. WE WILL HAVE SOME PASSING MID TO HIGH LEVEL CLOUDS THIS MORNING WITH AN EXPECTED AFTERNOON CLEARING. OTHERWISE...FORECAST IS ON TRACK. && .AVIATION...VFR. MOSTLY CLEAR IN SE OREGON. MOSTLY CLOUDY WITH SCT- BKN MID-HIGH LEVEL CLOUDS ALONG WITH ISOLATED -SHRA IN SW IDAHO THIS MORNING...THEN CLOUDS DECREASING IN THE AFTERNOON. SURFACE WINDS... VARIABLE 10 KNOTS OR LESS BECOMING SOUTHWEST-NORTHWEST 5-15 KNOTS WITH LOCAL GUSTS TO 20 KNOTS AFTER 18Z. WINDS ALOFT...SOUTHWEST 20- 30 KNOTS UP THROUGH 10K FEET MSL. SUNDAY OUTLOOK...VFR WITH SCT-BKN MID AND HIGH LEVEL CLOUDS. SURFACE WINDS GENERALLY 10 KNOTS OR LESS. && .PREV DISCUSSION... SHORT TERM...TODAY THROUGH SUNDAY...6Z GFS NAILED THE SMALL AREA OF SHOWERS AND THUNDERSTORMS ACROSS SW IDAHO AS OF 425 AM SO WILL UPDATE WITH THAT AND HRRR FOR CELLS LIFTING NE THROUGH MID MORNING. /END UPDATE/...CLOUDINESS THIS MORNING OVER SW IDAHO /WITH A COLD FRONT/ WILL EXIT E LEAVING MOSTLY SUNNY CONDITIONS WITH TWO EXCEPTIONS. HIGH BASED CU IS EXPECTED NEAR THE OREGON BLUE MTNS THIS AFTERNOON/EVENING AND SOME CLOUDS WILL LINGER OVER S CENTRAL IDAHO NEAR THE DRY COLD FRONT. PRECIP NO LONGER EXPECTED FOR SRN TWF COUNTY BUT RATHER FARTHER S/E. WAVY COLD FRONT IS EXPECTED TO REMAIN S AND E OF OUR AREA THROUGH SUNDAY...WITH CLOUDINESS ALONG THE ID-NV BORDER AGAIN SUNDAY AFTERNOON...BUT NO PRECIPITATION. NAM/EC KEEP A BIT STRONGER UPPER RIDGE OVER US...ABOUT 30M LESS HEIGHT FALLS THAN GFS...SO NUDGED HIGH TEMPS UP A LITTLE THIS WEEKEND. THIS IS A DRIER AND SLIGHTLY WARMER FORECAST THAN PREVIOUSLY. LOW LAYER 0-3KM WINDS UP TO 30 MPH YESTERDAY WILL WEAKEN THROUGH THE WEEKEND. SO EXPOSED/WELL MIXED AREAS WILL HAVE GUSTS UP TO 25 MPH TODAY AND 20 MPH SUNDAY AFTERNOON...WHILE MOST AREAS HAVE LIGHT DIURNAL WINDS UP TO 10 MPH. LONG TERM...SUNDAY NIGHT THROUGH SATURDAY...SOUTHWESTERLY FLOW WILL CONTINUE THROUGH WEDNESDAY. COOLER TEMPERATURES ALOFT WILL MOVE OVER THE REGION WITH A GRADUAL COOLING TREND EXPECTED. A CHANCE OF SHOWERS AND THUNDERSTORMS /MAINLY OVER THE HIGHER TERRAIN/ AS A SERIES OF SHORTWAVES MOVES ACROSS THE REGION TUESDAY/WEDNESDAY AFTERNOON. ZONAL FLOW WILL DEVELOP BEHIND THIS SHORTWAVE FRIDAY AND SATURDAY WITH DRY AIR MOVING ACROSS THE REGION AND SEASONABLE TEMPERATURES FOR THE REMAINDER OF THE PERIOD. && .BOI WATCHES/WARNINGS/ADVISORIES... ID...NONE. OR...NONE. && $$ WEATHER.GOV/BOISE DISCUSSION...AB AVIATION.....BW PREV SHORT TERM...VM PREV LONG TERM....KA
AREA FORECAST DISCUSSION...CORRECTED
NWS BOISE ID
323 AM MDT SAT SEP 26 2015 .SHORT TERM...TODAY THROUGH SUNDAY...6Z GFS NAILED THE SMALL AREA OF SHOWERS AND THUNDERSTORMS ACROSS SW IDAHO AS OF 425 AM SO WILL UPDATE WITH THAT AND HRRR FOR CELLS LIFTING NE THROUGH MIOD MORNING. /END UPDATE/...CLOUDINESS THIS MORNING OVER SW IDAHO /WITH A COLD FRONT/ WILL EXIT E LEAVING MOSTLY SUNNY CONDITIONS WITH TWO EXCEPTIONS. HIGH BASED CU IS EXPECTED NEAR THE OREGON BLUE MTNS THIS AFTERNOON/EVENING AND SOME CLOUDS WILL LINGER OVER S CENTRAL IDAHO NEAR THE DRY COLD FRONT. PRECIP NO LONGER EXPECTED FOR SRN TWF COUNTY BUT RATHER FARTHER S/E. WAVY COLD FRONT IS EXPECTED TO REMAIN S AND E OF OUR AREA THROUGH SUNDAY...WITH CLOUDINESS ALONG THE ID-NV BORDER AGAIN SUNDAY AFTERNOON...BUT NO PRECIPITATION. NAM/EC KEEP A BIT STRONGER UPPER RIDGE OVER US...ABOUT 30M LESS HEIGHT FALLS THAN GFS...SO NUDGED HIGH TEMPS UP A LITTLE THIS WEEKEND. THIS IS A DRIER AND SLIGHTLY WARMER FORECAST THAN PREVIOUSLY. LOW LAYER 0-3KM WINDS UP TO 30 MPH YESTERDAY WILL WEAKEN THROUGH THE WEEKEND. SO EXPOSED/WELL MIXED AREAS WILL HAVE GUSTS UP TO 25 MPH TODAY AND 20 MPH SUNDAY AFTERNOON...WHILE MOST AREAS HAVE LIGHT DIURNAL WINDS UP TO 10 MPH. .LONG TERM...SUNDAY NIGHT THROUGH SATURDAY...SOUTHWESTERLY FLOW WILL CONTINUE THROUGH WEDNESDAY. COOLER TEMPERATURES ALOFT WILL MOVE OVER THE REGION WITH A GRADUAL COOLING TREND EXPECTED. A CHANCE OF SHOWERS AND THUNDERSTORMS /MAINLY OVER THE HIGHER TERRAIN/ AS A SERIES OF SHORTWAVES MOVES ACROSS THE REGION TUESDAY/WEDNESDAY AFTERNOON. ZONAL FLOW WILL DEVELOP BEHIND THIS SHORTWAVE FRIDAY AND SATURDAY WITH DRY AIR MOVING ACROSS THE REGION AND SEASONABLE TEMPERATURES FOR THE REMAINDER OF THE PERIOD. && .AVIATION...VFR. SCATTERED MID-HIGH CLOUDS. SURFACE WINDS VARIABLE 12KT OR LESS BECOMING SOUTHWEST 5-15KT WITH GUSTS TO 20KT IN SOUTHEAST OREGON AND CENTRAL IDAHO MOUNTAINS THIS AFTERNOON. WINDS ALOFT AT 10K FT MSL...SW 20-30KT. SUNDAY OUTLOOK...SCT-BKN HIGH AND MID CLOUDS. SURFACE WINDS GENERALLY 10KT OR LESS...BECOMING NW 5-15KT SUNDAY AFTERNOON. && .BOI WATCHES/WARNINGS/ADVISORIES... ID...NONE. OR...NONE. && $$ WEATHER.GOV/BOISE SHORT TERM...VM LONG TERM....KA AVIATION.....KA
AREA FORECAST DISCUSSION
NWS LINCOLN IL
900 PM CDT SUN SEP 27 2015 .UPDATE... ISSUED AT 900 PM CDT SUN SEP 27 2015 Still a lot of clouds over the area but see some breaks in the east. Not enough breaks to make me want to change the sky cover forecast as still expecting mostly cloudy skies. If skies become more partly cloudy later, then will have to update then...just not yet. Overall forecast looks good this evening and see no reason to update at this time. && .SHORT TERM...(TONIGHT) ISSUED AT 246 PM CDT SUN SEP 27 2015 Cloud cover remains fairly extensive across the area today, with the earlier breaks near the I-74 corridor quickly filling in late morning with diurnal cumulus. A few showers have been tracking northwest out of southern Illinois, associated with what is left of the upper low over the Tennessee Valley. Forecast soundings not really showing much in the way of clearing this evening, with skies mainly partly to mostly cloudy. A feature of interest is overnight, with the last few runs of the RAP showing a surge of stratus advecting northeast into our area after midnight and covering most of the state, along with some dense fog late in the night. The latest NAM model favors more of a patchy fog scenario, which would seem more likely given the lack of widespread clearing plus not much of a wind field to advect the low clouds into this area, so will continue with mention of patchy fog for now. .LONG TERM...(Monday THROUGH Sunday) ISSUED AT 246 PM CDT SUN SEP 27 2015 While by no means certain at this point, a bit more clarity has started to develop in the forecast for the remainder of the week. Above normal temperatures are expected to linger for a couple more days, then trend toward normal in the wake of Tuesday`s cold front, with below normal temperatures possible by the weekend as some degree of upper troffing develops across eastern North America. The model consensus has also trended back toward a drier solution for the week, with the best chances of rainfall occurring in the vicinity of the frontal passage on Tuesday. Maintained a very low chance for rainfall on Monday as weak disturbances track northeast up the Ohio River Valley from the Gulf of Mexico. However, the very modest forcing and instability support little more than we are currently seeing across southern Illinois today as far as coverage and intensity. A cold front, currently extending from northern Ontario into the central Plains, will sink southeast across the forecast area later Monday night into Tuesday. This front will not have much going for it as far as support for precipitation production. The best forcing will remain across Canada with the faster upper-level flow, with the best moisture bottled up with a system along the Gulf coast. So, plan to keep PoPs on the low side with fropa, and it is entirely possible that most locations will remain dry. However, this appears to be our best shot for widespread rainfall this week. A Canadian surface high builds into the area behind the cold front, which should help shave several degrees of the daily max/min temperatures. Aloft, the flow across North America is expected to transition from mostly zonal to more of a troffy pattern. However, exactly how the upper pattern will look by late week and how we`ll get there is still very much up for debate. Model spread remain significant, with the spaghetti plots looking much like a pile of spaghetti. There does not appear to be a strong signal for rainfall at any one time, although there is some consensus that it is possible over the weekend. Expect the weekend to be more dry than not, but there will certainly be some risk of rain. We`ll have to see how the models eventually resolve the coming pattern shift to pin point the threat better. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z Monday EVENING) ISSUED AT 613 PM CDT SUN SEP 27 2015 ...Correction here to mention scattered pcpn on radar... Based on satellite loops, looks like broken clouds will remain over the area tonight and possibly the entire 24hr TAF period. Could be some breaks this evening and overnight, but not very optimistic at this time. Cigs are VFR levels and believe this will continue this evening. Models continue to show MVFR cigs later tonight, after midnight. And believe this still possible. So will keep MVFR cigs around 2.5kft at all sites starting after midnight with scattered clouds below 1kft. Then expecting cigs to get higher tomorrow during the morning hours and then last through the day. Radar also shows some very light and scattered pcpn this evening. Believe this will continue for several more hours, but do not think it warrants mention in the TAFs as it should be very, very brief and should not affect cigs or vis. Light southeast winds expected to become southerly overnight. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...Auten SHORT TERM...Geelhart LONG TERM...Bak AVIATION...Auten
AREA FORECAST DISCUSSION
NWS LINCOLN IL
613 PM CDT SUN SEP 27 2015 .SHORT TERM...(TONIGHT) ISSUED AT 246 PM CDT SUN SEP 27 2015 Cloud cover remains fairly extensive across the area today, with the earlier breaks near the I-74 corridor quickly filling in late morning with diurnal cumulus. A few showers have been tracking northwest out of southern Illinois, associated with what is left of the upper low over the Tennessee Valley. Forecast soundings not really showing much in the way of clearing this evening, with skies mainly partly to mostly cloudy. A feature of interest is overnight, with the last few runs of the RAP showing a surge of stratus advecting northeast into our area after midnight and covering most of the state, along with some dense fog late in the night. The latest NAM model favors more of a patchy fog scenario, which would seem more likely given the lack of widespread clearing plus not much of a wind field to advect the low clouds into this area, so will continue with mention of patchy fog for now. .LONG TERM...(Monday THROUGH Sunday) ISSUED AT 246 PM CDT SUN SEP 27 2015 While by no means certain at this point, a bit more clarity has started to develop in the forecast for the remainder of the week. Above normal temperatures are expected to linger for a couple more days, then trend toward normal in the wake of Tuesday`s cold front, with below normal temperatures possible by the weekend as some degree of upper troffing develops across eastern North America. The model consensus has also trended back toward a drier solution for the week, with the best chances of rainfall occurring in the vicinity of the frontal passage on Tuesday. Maintained a very low chance for rainfall on Monday as weak disturbances track northeast up the Ohio River Valley from the Gulf of Mexico. However, the very modest forcing and instability support little more than we are currently seeing across southern Illinois today as far as coverage and intensity. A cold front, currently extending from northern Ontario into the central Plains, will sink southeast across the forecast area later Monday night into Tuesday. This front will not have much going for it as far as support for precipitation production. The best forcing will remain across Canada with the faster upper-level flow, with the best moisture bottled up with a system along the Gulf coast. So, plan to keep PoPs on the low side with fropa, and it is entirely possible that most locations will remain dry. However, this appears to be our best shot for widespread rainfall this week. A Canadian surface high builds into the area behind the cold front, which should help shave several degrees of the daily max/min temperatures. Aloft, the flow across North America is expected to transition from mostly zonal to more of a troffy pattern. However, exactly how the upper pattern will look by late week and how we`ll get there is still very much up for debate. Model spread remain significant, with the spaghetti plots looking much like a pile of spaghetti. There does not appear to be a strong signal for rainfall at any one time, although there is some consensus that it is possible over the weekend. Expect the weekend to be more dry than not, but there will certainly be some risk of rain. We`ll have to see how the models eventually resolve the coming pattern shift to pin point the threat better. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z Monday EVENING) ISSUED AT 613 PM CDT SUN SEP 27 2015 Based on satellite loops, looks like broken clouds will remain over the area tonight and possibly the entire 24hr TAF period. Could be some breaks this evening and overnight, but not very optimistic at this time. Cigs are VFR levels and believe this will continue this evening. Models continue to show MVFR cigs later tonight, after midnight. And believe this still possible. So will keep MVFR cigs around 2.5kft at all sites starting after midnight with scattered clouds below 1kft. Then expecting cigs to get higher tomorrow during the morning hours and then last through the day. Light southeast winds expected to become southerly overnight. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...Geelhart LONG TERM...Bak AVIATION...Auten
AREA FORECAST DISCUSSION
NWS GOODLAND KS
236 AM MDT SAT SEP 26 2015 .UPDATE... ISSUED AT 125 AM MDT SAT SEP 26 2015 FOG DEVELOPMENT OVER WESTERN PORTIONS OF THE TRI STATE REGION HAS DROPPED DOWN TO LESS THAN A MILE OVER PAST COUPLE HOURS... PROMPTING ISSUANCE OF A DENSE FOG ADVISORY THROUGH ABOUT 15Z SATURDAY. THIS WILL FOCUS ON AREAS FROM GOODLAND WESTWARD. AREAS TO THE EAST ARE SEEING SOME REDUCTION TO VISIBILITY BUT WILL BE MONITORED TO SEE IF DOWNTREND PUSHES TOWARDS ADVISORY CRITERIA. && .SHORT TERM...(THIS EVENING THROUGH SATURDAY) ISSUED AT 1245 PM MDT FRI SEP 25 2015 AN UPPER LEVEL LOW PRESSURE AREA CURRENTLY SPINNING OVER NORTHEAST KANSAS IS FORECAST MOVE SOUTHWEST TONIGHT REACHING WEST CENTRAL OKLAHOMA BY MORNING. DURING THE AFTERNOON HOURS THE LOW CONTINUES SOUTH-SOUTHWEST WITH A SHARP UPPER RIDGE AXIS JUST WEST OF THE AREA. MAIN WEATHER CONCERNS TONIGHT THROUGH MID MORNING SATURDAY WILL BE INCREASING BOUNDARY LAYER MOISTURE RESULTING IN WIDESPREAD LOW CLOUDS AND FOG. HAVE FOLLOWED THE HRRR REGARDING PLACEMENT AND LOWEST VISIBILITIES OF FOG WHICH FAVOR THE WESTERN 2/3 OF THE AREA. CURRENTLY HAVE VISIBILITIES DOWN TO 1/2 MILE IN THIS AREA. IF THE MODEL GUIDANCE IS RIGHT DENSE FOG WITH VISIBILITIES 1/4 MILE OR LESS WILL DEVELOP. WILL LET EVENING SHIFT GET ANOTHER LOOK AT 18Z AND 00Z MODEL DATA IN HOPES OF FINE TUNING AREAS UNDER THE GUN FOR DENSE FOG AND POSSIBLY ISSUE AN ADVISORY. LOW TEMPERATURES TONIGHT GENERALLY IN THE UPPER 40S TO MID 50S. HIGHS ON SATURDAY GENERALLY IN THE MID 70S TO LOW 80S. .LONG TERM...(TUESDAY THROUGH FRIDAY) ISSUED AT 235 AM MDT SAT SEP 26 2015 MODEL FORECASTS INDICATE A SMALL SUBTLE SHORTWAVE TROUGH WILL MOVE ACROSS THE HIGH PLAINS TUESDAY MORNING...WHICH WILL BRING CHANCES FOR SHOWERS AND THUNDERSTORMS MAINLY NORTH OF INTERSTATE 70. ONCE THE SHORTWAVE TROUGH MOVES EASTWARD...AN UPPER LEVEL RIDGE WILL AMPLIFY ACROSS THE FORECAST AREA TUESDAY NIGHT THROUGH THURSDAY. MODEL AGREEMENT HAS BECOME BETTER FOR THE CURRENT FORECAST ISSUANCE WITH ALIGNING WITH THE PREVIOUS ECMWF FORECAST. AS A RESULT...STILL LEANING ON THE ECMWF OUTPUT TO KEEP THE TRI STATE AREA DRY THROUGH THIS PERIOD. TEMPERATURES WILL WARM FROM THE UPPER 70S ON TUESDAY TO THE UPPER 80S ON THURSDAY UNDER THE RIDGE. MODEL SOLUTIONS DIVERGE A BIT ON FRIDAY AND BEYOND. BECAUSE OF THE CONSISTENCY WITH THE ECMWF...DECIDED TO ADJUST PRECIPITATION FORECAST TOWARDS THE DRY SIDE FOR FRIDAY. HOWEVER...A PROMINENT SHORTWAVE TROUGH ALOFT WILL MOVE INTO THE CENTRAL HIGH PLAINS FROM THE WEST...SO EXPECTING PRECIPITATION TO DEVELOP AND MOVE INTO THE REGION FROM THE WEST. WITH ECMWF CAPE VALUES ABOVE 1000 J/KG AND 0- 6 KM BULK SHEAR VALUES APPROACHING 50 KTS...A BOUT OF SEVERE WEATHER COULD DEVELOP. CHANCES FOR PRECIPITATION WILL LIKELY OCCUR FRIDAY LATE AFTERNOON AND EVENING. AFTER THE PASSAGE OF THE SHORTWAVE TROUGH AND ASSOCIATED SURFACE COLD FRONT...A SHORTWAVE RIDGE BUILDS BEHIND THE EXITING SYSTEM AND WILL BRING DRY WEATHER FOR THE BEGINNING OF NEXT WEEKEND. TEMPERATURES WILL COOL BACK TO NORMAL IN THE MID TO UPPER 70S. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 1119 PM MDT FRI SEP 25 2015 VFR TO IFR CONDITIONS FORECAST FOR THE 6Z TAFS. THIS SET OF TAFS WILL BE MORE STRAIGHT FORWARD DUE TO IFR CONDITIONS ALREADY OCCURRING AT BOTH SITES. EXPECT CONDITIONS TO CHANGE VERY LITTLE UNTIL AFTER 12Z. DUE TO THE MOIST ENVIRONMENT IN PLACE...EXPECT THE FOG/STRATUS TO BURN OFF A BIT MORE SLOWLY THAN NORMAL...SIMILAR TO YESTERDAY OR POSSIBLY AN HOUR OR SO LONGER. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...DENSE FOG ADVISORY UNTIL 9 AM MDT /10 AM CDT/ THIS MORNING FOR KSZ001-013-027. CO...DENSE FOG ADVISORY UNTIL 9 AM MDT THIS MORNING FOR COZ090>092. NE...NONE. && $$ UPDATE...JN SHORT TERM...99 LONG TERM...MK AVIATION...JTL
AREA FORECAST DISCUSSION
NWS GOODLAND KS
125 AM MDT SAT SEP 26 2015 .UPDATE... ISSUED AT 125 AM MDT SAT SEP 26 2015 FOG DEVELOPMENT OVER WESTERN PORTIONS OF THE TRI STATE REGION HAS DROPPED DOWN TO LESS THAN A MILE OVER PAST COUPLE HOURS... PROMPTING ISSUANCE OF A DENSE FOG ADVISORY THROUGH ABOUT 15Z SATURDAY. THIS WILL FOCUS ON AREAS FROM GOODLAND WESTWARD. AREAS TO THE EAST ARE SEEING SOME REDUCTION TO VISIBILITY BUT WILL BE MONITORED TO SEE IF DOWNTREND PUSHES TOWARDS ADVISORY CRITERIA. && .SHORT TERM...(THIS EVENING THROUGH SATURDAY) ISSUED AT 1245 PM MDT FRI SEP 25 2015 AN UPPER LEVEL LOW PRESSURE AREA CURRENTLY SPINNING OVER NORTHEAST KANSAS IS FORECAST MOVE SOUTHWEST TONIGHT REACHING WEST CENTRAL OKLAHOMA BY MORNING. DURING THE AFTERNOON HOURS THE LOW CONTINUES SOUTH-SOUTHWEST WITH A SHARP UPPER RIDGE AXIS JUST WEST OF THE AREA. MAIN WEATHER CONCERNS TONIGHT THROUGH MID MORNING SATURDAY WILL BE INCREASING BOUNDARY LAYER MOISTURE RESULTING IN WIDESPREAD LOW CLOUDS AND FOG. HAVE FOLLOWED THE HRRR REGARDING PLACEMENT AND LOWEST VISIBILITIES OF FOG WHICH FAVOR THE WESTERN 2/3 OF THE AREA. CURRENTLY HAVE VISIBILITIES DOWN TO 1/2 MILE IN THIS AREA. IF THE MODEL GUIDANCE IS RIGHT DENSE FOG WITH VISIBILITIES 1/4 MILE OR LESS WILL DEVELOP. WILL LET EVENING SHIFT GET ANOTHER LOOK AT 18Z AND 00Z MODEL DATA IN HOPES OF FINE TUNING AREAS UNDER THE GUN FOR DENSE FOG AND POSSIBLY ISSUE AN ADVISORY. LOW TEMPERATURES TONIGHT GENERALLY IN THE UPPER 40S TO MID 50S. HIGHS ON SATURDAY GENERALLY IN THE MID 70S TO LOW 80S. .LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY) ISSUED AT 136 PM MDT FRI SEP 25 2015 UPPER RIDGE CENTERED OVER THE FOUR CORNERS WILL HOLD FIRM THROUGH MOST OF THE UPCOMING WEEK...WITH THE NEXT SHORTWAVE TROUGH CROSSING THE CENTRAL ROCKIES ON FRIDAY BRINGING WITH IT A CHANCE FOR THUNDERSTORMS. UNTIL THEN...DRY CONDITIONS AND ABOVE NORMAL TEMPERATURES ARE EXPECTED. LOW CLOUDS AND AREAS OF FOG WILL ALSO PERSIST IN THE OVERNIGHT HOURS SATURDAY NIGHT/SUNDAY MORNING AND POSSIBLY AGAIN SUNDAY NIGHT/MONDAY MORNING WITH PLENTIFUL LOW LEVEL MOISTURE. THERE WILL BE A WEAK COLD FRONT ATTEMPTING TO SLIP SOUTHWARD INTO THE AREA MONDAY AFTERNOON AND EVENING WITH INCREASING CLOUDS. HOWEVER...UPPER SUPPORT WILL BE DISPLACED FAR TO THE NORTH RULING OUT MOST IF NOT ALL PRECIPITATION CHANCES BUT REINFORCING MOIST LOW LEVELS WITH A POST FRONTAL UPSLOPE FLOW THROUGH TUESDAY. FOR THE LATE WEEK SYSTEM...INSTABILITY CURRENTLY LOOKS RATHER MEAGER BUT DEEP LAYER SHEAR WILL BE EXCELLENT ON FRIDAY...ON THE ORDER OF 50KTS...SO A SEVERE THREAT CANNOT BE RULED OUT JUST YET. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 1119 PM MDT FRI SEP 25 2015 VFR TO IFR CONDITIONS FORECAST FOR THE 6Z TAFS. THIS SET OF TAFS WILL BE MORE STRAIGHT FORWARD DUE TO IFR CONDITIONS ALREADY OCCURRING AT BOTH SITES. EXPECT CONDITIONS TO CHANGE VERY LITTLE UNTIL AFTER 12Z. DUE TO THE MOIST ENVIRONMENT IN PLACE...EXPECT THE FOG/STRATUS TO BURN OFF A BIT MORE SLOWLY THAN NORMAL...SIMILAR TO YESTERDAY OR POSSIBLY AN HOUR OR SO LONGER. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...DENSE FOG ADVISORY UNTIL 9 AM MDT /10 AM CDT/ THIS MORNING FOR KSZ001-013-027. CO...DENSE FOG ADVISORY UNTIL 9 AM MDT THIS MORNING FOR COZ090>092. NE...NONE. && $$ UPDATE...JN SHORT TERM...99 LONG TERM...024 AVIATION...JTL
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1127 PM MDT FRI SEP 25 2015 .SHORT TERM...(THIS EVENING THROUGH SATURDAY) ISSUED AT 1245 PM MDT FRI SEP 25 2015 AN UPPER LEVEL LOW PRESSURE AREA CURRENTLY SPINNING OVER NORTHEAST KANSAS IS FORECAST MOVE SOUTHWEST TONIGHT REACHING WEST CENTRAL OKLAHOMA BY MORNING. DURING THE AFTERNOON HOURS THE LOW CONTINUES SOUTH-SOUTHWEST WITH A SHARP UPPER RIDGE AXIS JUST WEST OF THE AREA. MAIN WEATHER CONCERNS TONIGHT THROUGH MID MORNING SATURDAY WILL BE INCREASING BOUNDARY LAYER MOISTURE RESULTING IN WIDESPREAD LOW CLOUDS AND FOG. HAVE FOLLOWED THE HRRR REGARDING PLACEMENT AND LOWEST VISIBILITIES OF FOG WHICH FAVOR THE WESTERN 2/3 OF THE AREA. CURRENTLY HAVE VISIBILITIES DOWN TO 1/2 MILE IN THIS AREA. IF THE MODEL GUIDANCE IS RIGHT DENSE FOG WITH VISIBILITIES 1/4 MILE OR LESS WILL DEVELOP. WILL LET EVENING SHIFT GET ANOTHER LOOK AT 18Z AND 00Z MODEL DATA IN HOPES OF FINE TUNING AREAS UNDER THE GUN FOR DENSE FOG AND POSSIBLY ISSUE AN ADVISORY. LOW TEMPERATURES TONIGHT GENERALLY IN THE UPPER 40S TO MID 50S. HIGHS ON SATURDAY GENERALLY IN THE MID 70S TO LOW 80S. .LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY) ISSUED AT 136 PM MDT FRI SEP 25 2015 UPPER RIDGE CENTERED OVER THE FOUR CORNERS WILL HOLD FIRM THROUGH MOST OF THE UPCOMING WEEK...WITH THE NEXT SHORTWAVE TROUGH CROSSING THE CENTRAL ROCKIES ON FRIDAY BRINGING WITH IT A CHANCE FOR THUNDERSTORMS. UNTIL THEN...DRY CONDITIONS AND ABOVE NORMAL TEMPERATURES ARE EXPECTED. LOW CLOUDS AND AREAS OF FOG WILL ALSO PERSIST IN THE OVERNIGHT HOURS SATURDAY NIGHT/SUNDAY MORNING AND POSSIBLY AGAIN SUNDAY NIGHT/MONDAY MORNING WITH PLENTIFUL LOW LEVEL MOISTURE. THERE WILL BE A WEAK COLD FRONT ATTEMPTING TO SLIP SOUTHWARD INTO THE AREA MONDAY AFTERNOON AND EVENING WITH INCREASING CLOUDS. HOWEVER...UPPER SUPPORT WILL BE DISPLACED FAR TO THE NORTH RULING OUT MOST IF NOT ALL PRECIPITATION CHANCES BUT REINFORCING MOIST LOW LEVELS WITH A POST FRONTAL UPSLOPE FLOW THROUGH TUESDAY. FOR THE LATE WEEK SYSTEM...INSTABILITY CURRENTLY LOOKS RATHER MEAGER BUT DEEP LAYER SHEAR WILL BE EXCELLENT ON FRIDAY...ON THE ORDER OF 50KTS...SO A SEVERE THREAT CANNOT BE RULED OUT JUST YET. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 1119 PM MDT FRI SEP 25 2015 VFR TO IFR CONDITIONS FORECAST FOR THE 6Z TAFS. THIS SET OF TAFS WILL BE MORE STRAIGHT FORWARD DUE TO IFR CONDITIONS ALREADY OCCURRING AT BOTH SITES. EXPECT CONDITIONS TO CHANGE VERY LITTLE UNTIL AFTER 12Z. DUE TO THE MOIST ENVIRONMENT IN PLACE...EXPECT THE FOG/STRATUS TO BURN OFF A BIT MORE SLOWLY THAN NORMAL...SIMILAR TO YESTERDAY OR POSSIBLY AN HOUR OR SO LONGER. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...99 LONG TERM...024 AVIATION...JTL
AREA FORECAST DISCUSSION
NWS JACKSON KY
127 PM EDT SAT SEP 26 2015 .UPDATE... ISSUED AT 1123 AM EDT SAT SEP 26 2015 WSR-88D RADAR CONTINUES TO SHOW AREA OF MOST ROBUST SHOWERS MOVING NORTHWEST INTO CENTRAL KY THIS LATE MORNING HOUR. DID KEEP NUMEROUS POPS NEARER THE LMK CWA BORDER...BUT BRING MORE IN THE WAY OF SCATTERED SHOWER FOR MUCH OF THE REGION. GIVEN DOWN STREAM RETURNS BEING LOWER THIS SEEMED THE BEST OVERALL APPROACH. OVERALL CONSSHORT AND HRRR SEEM TO HAVE THE BETTER HANDLE ON THIS...SO LEANED IN THAT DIRECTION. HOWEVER THE HRRR WANTED TO INCREASE THE INTENSITY OF SCATTERED AREA OF SHOWERS SE OF JACKSON. RIGHT NOW NOT REALLY SEEING THIS BEING ALL THAT REALISTIC BUT WILL CONTINUE TO MONITOR THAT. ALSO UPDATED THE WINDS PARTICULARLY IN THE RIDGES AND BLUEGRASS AREAS. THIS IS IN PART DUE TO A DECENT 925MB JET COMING ACROSS PORTIONS OF THE REGION THIS MORNING...WITH SYM HAVING SOME DECENT GUSTS INTO THE 13 TO 16 KNOT RANGE THIS MORNING. UPDATED TEMPS/DEWS/WINDS WITH LATEST OBS AND TRENDS AS WELL. UPDATE ISSUED AT 732 AM EDT SAT SEP 26 2015 SHOWERS ARE TURNING A BIT MORE ROBUST THAN IT LOOKED LIKE THEY WOULD BE EARLIER. THUS...HAVE WENT AHEAD AND INCREASED POPS AREAWIDE. NO OTHER CHANGES MADE AT THIS TIME. && .SHORT TERM...(TODAY THROUGH SUNDAY) ISSUED AT 315 AM EDT SAT SEP 26 2015 AN UPPER LEVEL LOW REMAINS OVER THE SOUTHERN APPALACHIANS THIS MORNING WITH POCKETS OF RAIN CONTINUING TO WRAP AROUND ACROSS THE SOUTHEAST...BACK INTO THE OHIO RIVER VALLEY. A FEW SHOWERS STILL AFFECTING AREAS JUST NORTH OF I-64 THIS MORNING...BUT THESE SHOULD PUSH OFF TO THE NORTH BY DAYBREAK. THE REST OF EASTERN KENTUCKY REMAINS UNDER THE INFLUENCE OF STRONG DOWNSLOPING EAST/SOUTHEAST WINDS. THIS HAS KEPT MUCH OF THE AREA DRY OVER THE LAST 3 TO 6 HOURS. AS THE UPPER LEVEL LOW LIFTS INTO SOUTH CENTRAL KENTUCKY THIS MORNING...WE MAY SEE SOME SHOWERS BECOME A BIT MORE WIDESPREAD ACROSS SOUTHERN KENTUCKY...STRETCHING UP THE I-75 CORRIDOR. THUS...WILL PLAN TO GO WITH HIGH SCATTERED TO NUMEROUS SHOWERS FOR OUR SOUTHWESTERN COUNTIES. FARTHER NORTHEAST...NOT MUCH SUPPORT FOR SHOWERS THROUGH THE DAY AS FORCING REMAINS WEAK. THE COMBINATION OF WEAK FORCING AND THE DOWNSLOPING FLOW WILL KEEP THINGS IN CHECK TODAY. THUS...WILL JUST GO WITH ISOLATED SHOWERS FOR MUCH OF THE AREA THROUGH THE DAY. TONIGHT...NOT MUCH CHANGE EXPECTED...EXCEPT THE UPPER LEVEL LOW LIFT FARTHER NORTH. BEST CHANCE OF RAIN WILL REMAIN TO THE EAST...BUT AGAIN RAIN CHANCES WILL REMAIN LOW. AS THE LOW CONTINUES TO EXIT SUNDAY...RAIN CHANCES WILL TAPER OFF COMPLETELY. HIGHS WILL REMAIN COOL TODAY...STRUGGLING TO REACH 70 ONCE AGAIN WITH ALL THE CLOUD COVER. CLOUDS MAY THIN A BIT ON SUNDAY...ALLOWING A BETTER RECOVER FOR TEMPERATURES...SO WILL GO WITH MID 70S FOR HIGHS. .LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY) ISSUED AT 420 AM EDT SAT SEP 26 2015 THE EXTENDED PORTION OF THE FORECAST BEGINS ON SUNDAY NIGHT WITH A RIDGE OVER THE NORTHEASTERN CONUS SHIFT TO THE EAST AS A STRONG TROUGH BEGINS TO DIVE SOUTHEAST THROUGH THE UPPER PLAINS AND INTO THE OH VALLEY BY TUESDAY. MEANWHILE DURING THIS TIME...A COUPLE TROPICAL DISTURBANCES WILL REMAIN OVER THE SOUTHEASTERN CONUS CONTINUING TO BRING SOME MOISTURE INTO THE AREA IN SOUTHEASTERLY FLOW. THE MENTIONED TROUGH WILL PUSH THROUGH THE OH VALLEY AND OFF TO THE EAST BY WEDNESDAY. A SECONDARY TROUGH WILL PUSH SOUTHEAST THROUGH THE AREA BY THURSDAY INTO FRIDAY AS THE PATTERN TAKES ON A MORE AMPLIFIED LOOK WITH A DIGGING TROUGH IN THE EAST AND BUILDING RIDGE OVER THE PLAINS. CLOSER TO THE SURFACE...THE SOUTHEASTERLY FLOW ACROSS THE APPALACHIAN MOUNTAINS WILL CONTINUE TO BRING MOISTURE INTO EASTERN KENTUCKY THROUGH SUNDAY NIGHT AND MONDAY NIGHT PROVIDING A CONTINUED SLIGHT CHANCE OF SHOWERS. WITH A STOUT CAP IN PLACE...ANY INSTABILITY WILL CERTAINLY NOT BE ENOUGH FOR ANY THUNDERSTORM DEVELOPMENT. THIS CHANGES HOWEVER BY TUESDAY AFTERNOON AS AN APPROACHING COLD FRONT FROM THE NORTHWEST MOVES INTO THE AREA. WITH THE MOISTURE IN PLACE AND FORCING FROM THE FRONT...INSTABILITY WILL BE ENOUGH FOR SOME THUNDERSTORM DEVELOPMENT SO HAVE PUT SOME THUNDER INTO THE FORECAST. THE FRONT THAT PUSHES THROUGH STALLS ACROSS KY BY WEDNESDAY AND THURSDAY LEAVING A DECENT GRADIENT ACROSS THE STATE AND WILL PROVIDE A CONTINUED AREA OF SHOWER DEVELOPMENT. WITH THIS...AN ADDITIONAL SHORTWAVE WILL PUSH THROUGH THE AREA ON FRIDAY. GIVEN THE FACT OF SOME RAINFALL THAT HAS ALREADY OCCURRED OVER THE AREA...THE SLIGHT INCONSISTENCY IN THE MODELS STILL ALLOWS FOR SOME PRECIP IN THE EXTENDED. THUS HAVE STAYED WITH THE SUPERBLEND SOLUTION FOR POPS THROUGH THE EXTENDED. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 128 PM EDT SAT SEP 26 2015 OVERALL SCATTERED RAIN SHOWERS REMAINS THE STORY FOR THE UPCOMING TAF PERIOD...THEREFORE HAVE KEPT THE MENTION OF SHRA AND VCSH THROUGH THE PERIOD. THIS HAS BEEN BROUGHT ON BY A UPPER LEVEL FEATURE THAT HAS CONTINUED TO RETROGRADE TO THE NW OVER THE PAST COUPLE OF DAYS. RIGHT NOW VIS SAT AND OBS ARE SHOWING IMPROVING CONDITIONS...BUT OCCASIONAL MVFR OR LOWER CANNOT BE RULED OUT IN ANY RAIN SHOWER ACTIVITY. WHILE MODEL SOUNDINGS CONTINUE TO BE DIVERGENT WITH THE OVERNIGHT CLOUDS...DID OPT TO INTRODUCE A HIGH MVFR DECK OVERNIGHT. THAT SAID THINK THE CIGS SHOULD BE SIMILAR TO TODAY WITH AFTERNOON VFR CONDITIONS. WINDS WILL BE GUSTIEST AT SYM WHERE WE HAVE SEEN SOME 15 PLUS KNOT GUST...OTHER SITES SEEING FAIRLY LIGHT WINDS. THE AREAS THAT WILL HAVE THE HIGHER WINDS WILL BE THE RIDGES AND THE BLUEGRASS...HOWEVER THIS IS EXPECTED TO DIMINISH OVERNIGHT. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...DJ SHORT TERM...KAS LONG TERM...SHALLENBERGER AVIATION...DJ
AREA FORECAST DISCUSSION
NWS JACKSON KY
1123 AM EDT SAT SEP 26 2015 .UPDATE... ISSUED AT 1123 AM EDT SAT SEP 26 2015 WSR-88D RADAR CONTINUES TO SHOW AREA OF MOST ROBUST SHOWERS MOVING NORTHWEST INTO CENTRAL KY THIS LATE MORNING HOUR. DID KEEP NUMEROUS POPS NEARER THE LMK CWA BORDER...BUT BRING MORE IN THE WAY OF SCATTERED SHOWER FOR MUCH OF THE REGION. GIVEN DOWN STREAM RETURNS BEING LOWER THIS SEEMED THE BEST OVERALL APPROACH. OVERALL CONSSHORT AND HRRR SEEM TO HAVE THE BETTER HANDLE ON THIS...SO LEANED IN THAT DIRECTION. HOWEVER THE HRRR WANTED TO INCREASE THE INTENSITY OF SCATTERED AREA OF SHOWERS SE OF JACKSON. RIGHT NOW NOT REALLY SEEING THIS BEING ALL THAT REALISTIC BUT WILL CONTINUE TO MONITOR THAT. ALSO UPDATED THE WINDS PARTICULARLY IN THE RIDGES AND BLUEGRASS AREAS. THIS IS IN PART DUE TO A DECENT 925MB JET COMING ACROSS PORTIONS OF THE REGION THIS MORNING...WITH SYM HAVING SOME DECENT GUSTS INTO THE 13 TO 16 KNOT RANGE THIS MORNING. UPDATED TEMPS/DEWS/WINDS WITH LATEST OBS AND TRENDS AS WELL. UPDATE ISSUED AT 732 AM EDT SAT SEP 26 2015 SHOWERS ARE TURNING A BIT MORE ROBUST THAN IT LOOKED LIKE THEY WOULD BE EARLIER. THUS...HAVE WENT AHEAD AND INCREASED POPS AREAWIDE. NO OTHER CHANGES MADE AT THIS TIME. && .SHORT TERM...(TODAY THROUGH SUNDAY) ISSUED AT 315 AM EDT SAT SEP 26 2015 AN UPPER LEVEL LOW REMAINS OVER THE SOUTHERN APPALACHIANS THIS MORNING WITH POCKETS OF RAIN CONTINUING TO WRAP AROUND ACROSS THE SOUTHEAST...BACK INTO THE OHIO RIVER VALLEY. A FEW SHOWERS STILL AFFECTING AREAS JUST NORTH OF I-64 THIS MORNING...BUT THESE SHOULD PUSH OFF TO THE NORTH BY DAYBREAK. THE REST OF EASTERN KENTUCKY REMAINS UNDER THE INFLUENCE OF STRONG DOWNSLOPING EAST/SOUTHEAST WINDS. THIS HAS KEPT MUCH OF THE AREA DRY OVER THE LAST 3 TO 6 HOURS. AS THE UPPER LEVEL LOW LIFTS INTO SOUTH CENTRAL KENTUCKY THIS MORNING...WE MAY SEE SOME SHOWERS BECOME A BIT MORE WIDESPREAD ACROSS SOUTHERN KENTUCKY...STRETCHING UP THE I-75 CORRIDOR. THUS...WILL PLAN TO GO WITH HIGH SCATTERED TO NUMEROUS SHOWERS FOR OUR SOUTHWESTERN COUNTIES. FARTHER NORTHEAST...NOT MUCH SUPPORT FOR SHOWERS THROUGH THE DAY AS FORCING REMAINS WEAK. THE COMBINATION OF WEAK FORCING AND THE DOWNSLOPING FLOW WILL KEEP THINGS IN CHECK TODAY. THUS...WILL JUST GO WITH ISOLATED SHOWERS FOR MUCH OF THE AREA THROUGH THE DAY. TONIGHT...NOT MUCH CHANGE EXPECTED...EXCEPT THE UPPER LEVEL LOW LIFT FARTHER NORTH. BEST CHANCE OF RAIN WILL REMAIN TO THE EAST...BUT AGAIN RAIN CHANCES WILL REMAIN LOW. AS THE LOW CONTINUES TO EXIT SUNDAY...RAIN CHANCES WILL TAPER OFF COMPLETELY. HIGHS WILL REMAIN COOL TODAY...STRUGGLING TO REACH 70 ONCE AGAIN WITH ALL THE CLOUD COVER. CLOUDS MAY THIN A BIT ON SUNDAY...ALLOWING A BETTER RECOVER FOR TEMPERATURES...SO WILL GO WITH MID 70S FOR HIGHS. .LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY) ISSUED AT 420 AM EDT SAT SEP 26 2015 THE EXTENDED PORTION OF THE FORECAST BEGINS ON SUNDAY NIGHT WITH A RIDGE OVER THE NORTHEASTERN CONUS SHIFT TO THE EAST AS A STRONG TROUGH BEGINS TO DIVE SOUTHEAST THROUGH THE UPPER PLAINS AND INTO THE OH VALLEY BY TUESDAY. MEANWHILE DURING THIS TIME...A COUPLE TROPICAL DISTURBANCES WILL REMAIN OVER THE SOUTHEASTERN CONUS CONTINUING TO BRING SOME MOISTURE INTO THE AREA IN SOUTHEASTERLY FLOW. THE MENTIONED TROUGH WILL PUSH THROUGH THE OH VALLEY AND OFF TO THE EAST BY WEDNESDAY. A SECONDARY TROUGH WILL PUSH SOUTHEAST THROUGH THE AREA BY THURSDAY INTO FRIDAY AS THE PATTERN TAKES ON A MORE AMPLIFIED LOOK WITH A DIGGING TROUGH IN THE EAST AND BUILDING RIDGE OVER THE PLAINS. CLOSER TO THE SURFACE...THE SOUTHEASTERLY FLOW ACROSS THE APPALACHIANMOUNTAINS WILL CONTINUE TO BRING MOISTURE INTO EASTERN KENTUCKY THROUGH SUNDAY NIGHT AND MONDAY NIGHT PROVIDING A CONTINUED SLIGHT CHANCE OF SHOWERS. WITH A STOUT CAP IN PLACE...ANY INSTABILITY WILL CERTAINLY NOT BE ENOUGH FOR ANY THUNDERSTORM DEVELOPMENT. THIS CHANGES HOWEVER BY TUESDAY AFTERNOON AS AN APPROACHING COLD FRONT FROM THE NORTHWEST MOVES INTO THE AREA. WITH THE MOISTURE IN PLACE AND FORCING FROM THE FRONT...INSTABILITY WILL BE ENOUGH FOR SOME THUNDERSTORM DEVELOPMENT SO HAVE PUT SOME THUNDER INTO THE FORECAST. THE FRONT THAT PUSHES THROUGH STALLS ACROSS KY BY WEDNESDAY AND THURSDAY LEAVING A DECENT GRADIENT ACROSS THE STATE AND WILL PROVIDE A CONTINUED AREA OF SHOWER DEVELOPMENT. WITH THIS...AN ADDITIONAL SHORTWAVE WILL PUSH THROUGH THE AREA ON FRIDAY. GIVEN THE FACT OF SOME RAINFALL THAT HAS ALREADY OCCURRED OVER THE AREA...THE SLIGHT INCONSISTENCY IN THE MODELS STILL ALLOWS FOR SOME PRECIP IN THE EXTENDED. THUS HAVE STAYED WITH THE SUPERBLEND SOLUTION FOR POPS THROUGH THE EXTENDED. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 732 AM EDT SAT SEP 26 2015 A MIXTURE OF IFR/MVFR CONDITIONS WILL BE SEEN THIS MORNING AS RAIN SHOWERS DEVELOP AND SPREAD ACROSS THE REGION. CIGS SHOULD INCREASE TO VFR BY EARLY THIS AFTERNOON...BUT RAIN SHOWER ACTIVITY WILL CONTINUE. STILL A LITTLE UNCERTAIN IF WE WILL STAY AT VFR TONIGHT...OR GO BACK DOWN AGAIN. MODEL GUIDANCE IS ALL OVER THE PLACE AND ITS CERTAINLY A DIFFICULT FORECAST EVEN 12 TO 18 HOURS OUT. FOR NOW...WILL JUST GO VFR AND SEE WHAT THE 12Z MODEL GUIDANCE HAS BEFORE INTRODUCING MORE LOW CLOUDS TONIGHT. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...DJ SHORT TERM...KAS LONG TERM...SHALLENBERGER AVIATION...KAS
AREA FORECAST DISCUSSION
NWS JACKSON KY
159 AM EDT SAT SEP 26 2015 .UPDATE... ISSUED AT 159 AM EDT SAT SEP 26 2015 A FEW SHOWERS HANGING ON ACROSS OUR FAR NORTHERN AND NORTHEAST COUNTIES OF KENTUCKY. REST OF THE AREA REMAINS DRY AS DOWNSLOPING FLOW HAS TAKEN OVER ONCE AGAIN. THE SHOWERS IN THE NORTH SHOULD DISSIPATE AS THEY MOVE NORTH OVER THE NEXT FEW HOURS. THEN THE DRY CONDITIONS WILL LIKELY PREVAIL THROUGH DAYBREAK. A FEW SHOWERS MAY CREEP INTO SOUTHERN KENTUCKY...WHERE THE EFFECTS OF THE DOWNSLOPING MAY BE A BIT WEAKER. NOT SURE HOW MUCH ACTIVITY WILL EXIST THROUGH THE DAY ON SATURDAY AS NOT MUCH CHANGE IS EXPECTED. THUS...WE COULD BE LOOKING AT DRY CONDITIONS FOR MOST OF THE AREA THROUGH THE DAY. WILL LIKELY KEEP AN ISOLATED POP IN THE FORECAST TO ACCOUNT FOR A FEW LIGHT SHOWERS MAKING IT OVER THE PEAKS OF THE APPALACHIANS. UPDATE HAS BEEN SAVED AND SENT. UPDATE ISSUED AT 1214 AM EDT SAT SEP 26 2015 BAND OF RAIN CONTINUES TO EXIT NORTHWARD WITH DRIER CONDITIONS SPREADING BACK INTO EASTERN KENTUCKY. WILL GO AHEAD AND BACK DOWN ON POPS FOR THE REST OF THE NIGHT AS DOWNSLOPING FLOW AND LACK OF FORCING WILL LIKELY KEEP THE WEATHER MUCH QUIETER THROUGH THE SECOND HALF OF THE NIGHT. SOME WEAK FORCING MAY SPREAD BACK TOWARDS THE TENNESSEE BORDER TOWARDS 12Z...SO WILL BRING BACK SOME BETTER POPS AROUND THIS TIME...AND ESPECIALLY AFTER DAYBREAK. UPDATE ISSUED AT 1050 PM EDT FRI SEP 25 2015 RAIN SHOWERS CONTINUE TO MOVE ACROSS THE AREA THIS EVENING. THE BULK OF PRECIPITATION IS OCCURRING ALONG AND NORTH OF THE MOUNTAIN PARKWAY. THESE SHOWERS WILL CONTINUE TO MOVE OFF TO THE NORTHWEST AND EVENTUALLY OUT OF THE AREA OVERNIGHT. ISOLATED TO SCATTERED RAIN SHOWERS ARE EXPECTED TO MOVE BACK INTO OUR SOUTHEASTERN COUNTIES OVERNIGHT...AND EVENTUALLY ACROSS ALL OF EASTERN KENTUCKY...AS ADDITIONAL WAVES OF MOISTURE AND UPPER LEVEL ENERGY MOVE IN FROM THE SOUTHEAST. ONLY VERY LIGHT RAIN AMOUNTS ARE EXPECTED FROM THE ACTIVITY LATER TONIGHT. AN UPDATED ZONE FORECAST TEXT PRODUCT HAS BEEN CREATED AND SENT OUT ALREADY WITH THE UPDATES MENTIONED ABOVE. UPDATE ISSUED AT 742 PM EDT FRI SEP 25 2015 MADE A NUMBER OF UPDATES TO THE FORECAST FOR THE REST OF TONIGHT. BASED ON CURRENT RADAR TRENDS...RAIN SHOWERS SOUTHEAST OF THE WEATHER OFFICE HAVE TAPERED OFF QUITE A BIT OVER THE PAST COUPLE OF HOURS...MAKING THE PREVIOUS PRECIPITATION PROBABILITIES TOO HIGH WHEN COMPARED TO REALITY. WIDESPREAD RAIN SHOWERS ARE ONGOING ACROSS A LARGE PORTION OF THE AREA...GENERAL ALONG AND NORTHWEST OF A LINE EXTENDING FROM WAYNE COUNTY NORTHEASTWARD INTO WEST CENTRAL PIKE COUNTY. THESE SHOWERS WILL CONTINUE TRACKING SLOWLY OFF TO THE NORTHWEST AS THE EVENING WEARS ON. BY 2 OR 3Z IT APPEARS THAT...BASED ON CURRENT RADAR TRENDS AND THE LATEST RUN OF THE HRRR MODEL...THAT THE RAIN SHOWERS WILL BECOME SCATTERED DURING THE OVERNIGHT PERIOD...DUE MAINLY TO A LACK OF RENEWED FORCING ALOFT COMING IN FROM THE SOUTHEAST. REGIONAL RADAR MOSAIC DOES SHOW SCATTERED SHOWERS CONTINUE TO FORM ACROSS EASTERN TENNESSEE AND THE CAROLINAS. THESE SHOWERS ARE WHAT WE EXPECT TO MOVE INTO OUR AREA THROUGHOUT THE EVENING AND OVERNIGHT PERIOD. THE POPS...QPF...POP12...AND WEATHER TYPE GRIDS HAVE BEEN UPDATED THROUGH 11Z SATURDAY...REFLECTING THE CHANGES MENTIONED ABOVE. A NEW SET OF ZONES WILL BE ISSUED SHORTLY. && .SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT) ISSUED AT 349 PM EDT FRI SEP 25 2015 18Z SFC ANALYSIS SHOWS LOW PRESSURE SPREADING NORTH INTO KENTUCKY BENEATH A DEVELOPING UPPER LOW. THIS IS SUPPORTING WAVES OF LIGHT TO MODERATE SHOWERS WORKING EAST TO WEST THROUGH EASTERN KENTUCKY. SO FAR...THE MORE SUBSTANTIAL RAIN HAS BEEN HELD UP OVER MUCH OF THE AREA DUE TO INITIAL DRY AIR AND DOWNSLOPING ON EAST TO NORTHEAST WINDS COMING OFF THE HIGHER TERRAIN. THE CLOUDS AND RAIN HAVE KEPT TEMPERATURES CAPPED THIS DAY WITH READINGS CURRENTLY IN THE LOW TO MID 60S THROUGHOUT EAST KENTUCKY. THE INCREASING SHOWERS HAVE HELPED TO SATURATE MUCH OF THE AREA WITH LOW 60S ACROSS SOUTHEAST PARTS OF THE CWA WHILE MID AND LOW 50S ARE NOTED TO THE NORTHWEST. WINDS...MEANWHILE...ARE GENERALLY FROM THE EAST AT 5 TO 10 KTS WITH OCCASIONAL GUSTS TO 15 KTS. THE MODELS REMAIN IN PRETTY GOOD AGREEMENT ALOFT AS THEY ALL DEPICT A CLOSED LOW FORMING OVER THE TENNESSEE VALLEY...AMID A REGION OF HIGH HEIGHTS...INTO SATURDAY MORNING. THIS UPPER LOW WILL THEN DRIFT NORTH INTO KENTUCKY THROUGH SUNDAY MORNING WHILE AMPLE AMOUNTS OF ENERGY SWIRLS AROUND ITS CENTER. THIS LOW WILL COMMENCE FILLING FOR THE LATTER PART OF THE SHORT TERM PERIOD... LESSENING ITS IMPACT ON SENSIBLE WEATHER FOR THE JKL CWA. GIVEN THE SIMILARITIES AMONG THE MODELS HAVE AGAIN FAVORED THE HIGHER RESOLUTION ONES LIKE THE RAP13 AND HRRR FOR WEATHER SPECIFICS... ALONG WITH THE NAM12 FROM LATER SATURDAY INTO SUNDAY MORNING. SENSIBLE WEATHER WILL FEATURE WAVES OF LIGHT TO MODERATE SHOWERS PUSHING ACROSS EAST KENTUCKY THROUGH THE NIGHT. THESE WILL STILL BE SOMEWHAT LIMITED BY DOWNSLOPING...BUT EVEN SO THERE WILL BE PLACES THAT MAKE OUT A BIT BETTER WITH UP TO THREE QUARTERS OF AN INCH POSSIBLE...LIKE PARTS OF HARLAN COUNTY. OTHERWISE...MOST PLACES WILL FALL IN THE QUARTER TO HALF INCH RANGE THROUGH SATURDAY MORNING. THE SHOWERS WILL LIKELY SLACKEN THROUGH THE DAY SATURDAY AS THE SFC LOW STARTS TO FALL APART AND THE UPPER SUPPORT WANES. THERE WILL STILL BE A THREAT OF LIGHT SHOWERS THROUGH THE NIGHT AND INTO SUNDAY MORNING...THOUGH...BUT QPF WILL LIKELY BE ALMOST NEGLIGIBLE...RUNNING AT A TENTH OF AN INCH OR LESS FOR MOST PLACES. GIVEN THE SATURATION THROUGH SUNDAY MORNING EXPECT FAIRLY UNIFORM TEMPERATURES AND A NARROW DIURNAL RANGE FOR THE BULK OF THE WEEKEND. USED THE SHORTBLEND INITIALLY FOR TEMPERATURES AND DEWPOINTS ONCE AGAIN...INTO THE FIRST PART OF THE DAY SATURDAY WITH THE SUPERBLEND TO FOLLOW THROUGH THE SUNDAY MORNING. DID MAKE SOME POINT BASED ADJUSTMENTS TO HIGHS AND LOWS THROUGH SATURDAY NIGHT. AS FOR POPS...ENDED UP SIMILAR TO A BLEND OF THE WETTER MAV AND DRIER MET MOS THROUGH THE PERIOD. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 350 PM EDT FRI SEP 25 2015 UPPER LEVEL LOW THAT RETROGRADES EAST THIS WEEKEND WILL EVENTUALLY BECOME MORE DIFFUSE AS WE MOVE INTO SUNDAY. AFTER THIS WEAK HEIGHT RISES OCCURS AHEAD OF MID WEEK TROUGHING. THE MODELS CONTINUE TO DIVERGE AS WE MOVE THROUGH THE LONG TERM PERIOD IN RELATION TO HEIGHTS AND OVERALL PATTERN. THE ECMWF WANTS TO ESTABLISH A DEEPER TROUGH...WHILE THE GFS REMAINS MUCH FLATTER WITH THE PATTERN. THIS OF COURSE WILL INTRODUCE ADDITIONAL COMPLICATIONS TO THE SURFACE. HOWEVER WOULD SEEM LIKE SURFACE FEATURES WILL LACKING THROUGH THE PERIOD...THEREFORE THE WEAKER WAVES WILL BE THE BEST SUPPORT. RIGHT NOW WILL LEAN TOWARD THE BLEND JUST GIVEN THAT CONFIDENCE REMAINS LOWER THROUGH THE LONG TERM PERIOD. BEST CHANCES OF RAIN LOOK TO BE TUESDAY THROUGH WEDNESDAY TIME FRAME WITH UPPER SHORTWAVE AND ENERVATED FRONT WEDNESDAY. TEMPERATURES THROUGH THE PERIOD WILL BE NEAR NORMAL...HOWEVER DEPENDING ON THE DEPTH OF THE TROUGHING TOWARD LATE NEXT WEEK COULD BRING TEMPS TO BELOW NORMAL VALUES. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 159 AM EDT SAT SEP 26 2015 VFR CONDITIONS HAVE SPREAD BACK INTO EASTERN KENTUCKY WITH EAST/SOUTHEAST DOWNSLOPING FLOW OFF THE HIGHER PEAKS OF THE APPALACHIANS. THIS WILL KEEP THE LOW CIGS FROM AFFECTING MUCH OF THE AREA THROUGH THE MORNING HOURS. THE FLOW WILL SLOWLY TURN MORE SOUTHEASTERLY THROUGH THE DAY AND TONIGHT...BEFORE TURNING SOUTH ON SUNDAY. GIVEN THIS FLOW...WE MAY SEE CONDITIONS STAY VFR THROUGH THE PERIOD...EXCEPT WHERE A FEW SHOWERS CAN GET GOING. BEST CHANCES FOR THESE SHOWERS MAY BE ACROSS FAR NORTHEAST KENTUCKY...OR FAR SOUTHERN KENTUCKY. OVERALL...IMPACTS TO AVIATION SHOULD NOT BE THAT GREAT THROUGH THE FORECAST PERIOD. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...KAS SHORT TERM...GREIF LONG TERM...DJ AVIATION...KAS
AREA FORECAST DISCUSSION
NWS JACKSON KY
1214 AM EDT SAT SEP 26 2015 .UPDATE... ISSUED AT 1214 AM EDT SAT SEP 26 2015 BAND OF RAIN CONTINUES TO EXIT NORTHWARD WITH DRIER CONDITIONS SPREADING BACK INTO EASTERN KENTUCKY. WILL GO AHEAD AND BACK DOWN ON POPS FOR THE REST OF THE NIGHT AS DOWNSLOPING FLOW AND LACK OF FORCING WILL LIKELY KEEP THE WEATHER MUCH QUIETER THROUGH THE SECOND HALF OF THE NIGHT. SOME WEAK FORCING MAY SPREAD BACK TOWARDS THE TENNESSEE BORDER TOWARDS 12Z...SO WILL BRING BACK SOME BETTER POPS AROUND THIS TIME...AND ESPECIALLY AFTER DAYBREAK. UPDATE ISSUED AT 1050 PM EDT FRI SEP 25 2015 RAIN SHOWERS CONTINUE TO MOVE ACROSS THE AREA THIS EVENING. THE BULK OF PRECIPITATION IS OCCURRING ALONG AND NORTH OF THE MOUNTAIN PARKWAY. THESE SHOWERS WILL CONTINUE TO MOVE OFF TO THE NORTHWEST AND EVENTUALLY OUT OF THE AREA OVERNIGHT. ISOLATED TO SCATTERED RAIN SHOWERS ARE EXPECTED TO MOVE BACK INTO OUR SOUTHEASTERN COUNTIES OVERNIGHT...AND EVENTUALLY ACROSS ALL OF EASTERN KENTUCKY...AS ADDITIONAL WAVES OF MOISTURE AND UPPER LEVEL ENERGY MOVE IN FROM THE SOUTHEAST. ONLY VERY LIGHT RAIN AMOUNTS ARE EXPECTED FROM THE ACTIVITY LATER TONIGHT. AN UPDATED ZONE FORECAST TEXT PRODUCT HAS BEEN CREATED AND SENT OUT ALREADY WITH THE UPDATES MENTIONED ABOVE. UPDATE ISSUED AT 742 PM EDT FRI SEP 25 2015 MADE A NUMBER OF UPDATES TO THE FORECAST FOR THE REST OF TONIGHT. BASED ON CURRENT RADAR TRENDS...RAIN SHOWERS SOUTHEAST OF THE WEATHER OFFICE HAVE TAPERED OFF QUITE A BIT OVER THE PAST COUPLE OF HOURS...MAKING THE PREVIOUS PRECIPITATION PROBABILITIES TOO HIGH WHEN COMPARED TO REALITY. WIDESPREAD RAIN SHOWERS ARE ONGOING ACROSS A LARGE PORTION OF THE AREA...GENERAL ALONG AND NORTHWEST OF A LINE EXTENDING FROM WAYNE COUNTY NORTHEASTWARD INTO WEST CENTRAL PIKE COUNTY. THESE SHOWERS WILL CONTINUE TRACKING SLOWLY OFF TO THE NORTHWEST AS THE EVENING WEARS ON. BY 2 OR 3Z IT APPEARS THAT...BASED ON CURRENT RADAR TRENDS AND THE LATEST RUN OF THE HRRR MODEL...THAT THE RAIN SHOWERS WILL BECOME SCATTERED DURING THE OVERNIGHT PERIOD...DUE MAINLY TO A LACK OF RENEWED FORCING ALOFT COMING IN FROM THE SOUTHEAST. REGIONAL RADAR MOSAIC DOES SHOW SCATTERED SHOWERS CONTINUE TO FORM ACROSS EASTERN TENNESSEE AND THE CAROLINAS. THESE SHOWERS ARE WHAT WE EXPECT TO MOVE INTO OUR AREA THROUGHOUT THE EVENING AND OVERNIGHT PERIOD. THE POPS...QPF...POP12...AND WEATHER TYPE GRIDS HAVE BEEN UPDATED THROUGH 11Z SATURDAY...REFLECTING THE CHANGES MENTIONED ABOVE. A NEW SET OF ZONES WILL BE ISSUED SHORTLY. && .SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT) ISSUED AT 349 PM EDT FRI SEP 25 2015 18Z SFC ANALYSIS SHOWS LOW PRESSURE SPREADING NORTH INTO KENTUCKY BENEATH A DEVELOPING UPPER LOW. THIS IS SUPPORTING WAVES OF LIGHT TO MODERATE SHOWERS WORKING EAST TO WEST THROUGH EASTERN KENTUCKY. SO FAR...THE MORE SUBSTANTIAL RAIN HAS BEEN HELD UP OVER MUCH OF THE AREA DUE TO INITIAL DRY AIR AND DOWNSLOPING ON EAST TO NORTHEAST WINDS COMING OFF THE HIGHER TERRAIN. THE CLOUDS AND RAIN HAVE KEPT TEMPERATURES CAPPED THIS DAY WITH READINGS CURRENTLY IN THE LOW TO MID 60S THROUGHOUT EAST KENTUCKY. THE INCREASING SHOWERS HAVE HELPED TO SATURATE MUCH OF THE AREA WITH LOW 60S ACROSS SOUTHEAST PARTS OF THE CWA WHILE MID AND LOW 50S ARE NOTED TO THE NORTHWEST. WINDS...MEANWHILE...ARE GENERALLY FROM THE EAST AT 5 TO 10 KTS WITH OCCASIONAL GUSTS TO 15 KTS. THE MODELS REMAIN IN PRETTY GOOD AGREEMENT ALOFT AS THEY ALL DEPICT A CLOSED LOW FORMING OVER THE TENNESSEE VALLEY...AMID A REGION OF HIGH HEIGHTS...INTO SATURDAY MORNING. THIS UPPER LOW WILL THEN DRIFT NORTH INTO KENTUCKY THROUGH SUNDAY MORNING WHILE AMPLE AMOUNTS OF ENERGY SWIRLS AROUND ITS CENTER. THIS LOW WILL COMMENCE FILLING FOR THE LATTER PART OF THE SHORT TERM PERIOD... LESSENING ITS IMPACT ON SENSIBLE WEATHER FOR THE JKL CWA. GIVEN THE SIMILARITIES AMONG THE MODELS HAVE AGAIN FAVORED THE HIGHER RESOLUTION ONES LIKE THE RAP13 AND HRRR FOR WEATHER SPECIFICS... ALONG WITH THE NAM12 FROM LATER SATURDAY INTO SUNDAY MORNING. SENSIBLE WEATHER WILL FEATURE WAVES OF LIGHT TO MODERATE SHOWERS PUSHING ACROSS EAST KENTUCKY THROUGH THE NIGHT. THESE WILL STILL BE SOMEWHAT LIMITED BY DOWNSLOPING...BUT EVEN SO THERE WILL BE PLACES THAT MAKE OUT A BIT BETTER WITH UP TO THREE QUARTERS OF AN INCH POSSIBLE...LIKE PARTS OF HARLAN COUNTY. OTHERWISE...MOST PLACES WILL FALL IN THE QUARTER TO HALF INCH RANGE THROUGH SATURDAY MORNING. THE SHOWERS WILL LIKELY SLACKEN THROUGH THE DAY SATURDAY AS THE SFC LOW STARTS TO FALL APART AND THE UPPER SUPPORT WANES. THERE WILL STILL BE A THREAT OF LIGHT SHOWERS THROUGH THE NIGHT AND INTO SUNDAY MORNING...THOUGH...BUT QPF WILL LIKELY BE ALMOST NEGLIGIBLE...RUNNING AT A TENTH OF AN INCH OR LESS FOR MOST PLACES. GIVEN THE SATURATION THROUGH SUNDAY MORNING EXPECT FAIRLY UNIFORM TEMPERATURES AND A NARROW DIURNAL RANGE FOR THE BULK OF THE WEEKEND. USED THE SHORTBLEND INITIALLY FOR TEMPERATURES AND DEWPOINTS ONCE AGAIN...INTO THE FIRST PART OF THE DAY SATURDAY WITH THE SUPERBLEND TO FOLLOW THROUGH THE SUNDAY MORNING. DID MAKE SOME POINT BASED ADJUSTMENTS TO HIGHS AND LOWS THROUGH SATURDAY NIGHT. AS FOR POPS...ENDED UP SIMILAR TO A BLEND OF THE WETTER MAV AND DRIER MET MOS THROUGH THE PERIOD. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 350 PM EDT FRI SEP 25 2015 UPPER LEVEL LOW THAT RETROGRADES EAST THIS WEEKEND WILL EVENTUALLY BECOME MORE DIFFUSE AS WE MOVE INTO SUNDAY. AFTER THIS WEAK HEIGHT RISES OCCURS AHEAD OF MID WEEK TROUGHING. THE MODELS CONTINUE TO DIVERGE AS WE MOVE THROUGH THE LONG TERM PERIOD IN RELATION TO HEIGHTS AND OVERALL PATTERN. THE ECMWF WANTS TO ESTABLISH A DEEPER TROUGH...WHILE THE GFS REMAINS MUCH FLATTER WITH THE PATTERN. THIS OF COURSE WILL INTRODUCE ADDITIONAL COMPLICATIONS TO THE SURFACE. HOWEVER WOULD SEEM LIKE SURFACE FEATURES WILL LACKING THROUGH THE PERIOD...THEREFORE THE WEAKER WAVES WILL BE THE BEST SUPPORT. RIGHT NOW WILL LEAN TOWARD THE BLEND JUST GIVEN THAT CONFIDENCE REMAINS LOWER THROUGH THE LONG TERM PERIOD. BEST CHANCES OF RAIN LOOK TO BE TUESDAY THROUGH WEDNESDAY TIME FRAME WITH UPPER SHORTWAVE AND ENERVATED FRONT WEDNESDAY. TEMPERATURES THROUGH THE PERIOD WILL BE NEAR NORMAL...HOWEVER DEPENDING ON THE DEPTH OF THE TROUGHING TOWARD LATE NEXT WEEK COULD BRING TEMPS TO BELOW NORMAL VALUES. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING) ISSUED AT 742 PM EDT FRI SEP 25 2015 WIDESPREAD RAIN SHOWERS WILL CONTINUE TO MOVE NORTHWEST ACROSS PORTIONS OF EASTERN KENTUCKY THIS EVENING AS AN A WEAK TROUGH OF LOW PRESSURE ALOFT SPINS OVER THE SOUTHEASTERN CONUS. THE RAIN SHOWERS HAVE BEGUN TO TAPER OFF ACROSS AN AREA ALONG AND SOUTHEAST OF A LINE EXTENDING FROM WAYNE COUNTY TO WEST CENTRAL PIKE COUNTY. THIS TREND IS EXPECTED TO CONTINUE THROUGH OUT THE EVENING...WITH SCATTERED SHOWERS EXPECTED ACROSS THE ENTIRE AREA BASED ON THE LATEST RADAR TRENDS AND SHORT TERM MODEL DATA. THE TAF SITES WILL EXPERIENCE FLUCTUATING CONDITIONS VARYING BETWEEN MVFR AND IFR THIS EVENING AND OVERNIGHT. THE RAIN SHOWERS SHOULD EXPAND IN COVERAGE A BIT TOWARDS DAWN...AS A SECOND LOBE OF ENERGY ROTATES AROUND A TROUGH OF LOW PRESSURE ALOFT AND INTO THE EASTERN TENNESSEE VALLEY AND EVENTUALLY EASTERN KENTUCKY. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...KAS SHORT TERM...GREIF LONG TERM...DJ AVIATION...AR
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
939 PM CDT SUN SEP 27 2015 .DISCUSSION... REMOVED ANY MENTION OF THUNDER OVERNIGHT AS INSTABILITY ALL NEAR COASTLINE AND SWD. ASIDE FROM THAT...MADE MINOR ADJUSTMENTS ON POPS...INCLUDING ADDING 20 PERCENT NORTH OF I-30...EVEN THOUGH RAIN SO LGT ACROSS NORTHERN STRETCHES OF AREA...MAY OR MAY NOT EXCEED TRACE AMOUNTS./VII/. && .PREV DISCUSSION... /ISSUED 703 PM CDT SUN SEP 27 2015/ AVIATION... EXTENSIVE ELEVATED CLOUD COVER IS IN PLACE ACROSS THE REGION THIS EVENING...WITH THIS WRAP-AROUND MOISTURE LINGERING NEAR AND N OF A CLOSED UPPER LOW ALONG THE SE TX COAST. THIS CLOUD COVER WILL PERSIST THROUGH MUCH OF THE TAF PERIOD...AS THE LOW REMAINS NEARLY STATIONARY ALONG THE COAST. AN EXTENSIVE AREA OF SHRA WITH EMBEDDED TSRA OFFSHORE NEAR THE CENTER OF THE SFC CIRCULATION ABOUT 100NM S OF SABINE PASS...SHOULD CONTINUE TO SLOWLY SPREAD NNW MAINLY INTO DEEP E TX/LOWER TOLEDO BEND COUNTRY OF WCNTRL LA THIS EVENING...PRIMARILY AFFECTING THE E TX TERMINALS OVERNIGHT. HAVE TEMPOED MENTION OF SHRA FOR THIS AREA FROM MID-EVENING THROUGH A PORTION OF THE OVERNIGHT HOURS FOR LFK ONLY...WITH MENTION OF VCSH FOR TYR/GGG LATE...ALTHOUGH ISOLATED -SHRA CAN/T BE RULED OUT OVER NW LA TONIGHT. HOWEVER...GIVEN THE ELEVATED CIGS AND VERY LIGHT NATURE OF THE RAIN...HAVE NOT MENTIONED VCSH FOR SHV ATTM. DRY SLOTTING ON THE E SIDE OF THE UPPER LOW OVER ECNTRL LA SHOULD LIMIT THE EXTENT OF SHRA DEVELOPMENT OVER THIS AREA THROUGH MONDAY AFTERNOON...WITH SCT SHRA POSSIBLE FARTHER W OVER WRN LA/E TX/SW AR NEAR THE ATTENDENT UPPER TROUGH AXIS. COULD ALSO SEE IFR/LOW MVFR CIGS DEVELOP/SPREAD W INTO SCNTRL AR/NCNTRL LA BY/AFTER 12Z MONDAY...AS WELL AS NEAR LFK...CLOSER TO THE RAIN AREA AS THE AIR MASS CONTINUES TO SATURATE. SHOULD SEE A SLOW IMPROVEMENT TO VFR CIGS BY MIDDAY MONDAY WHERE THE LOW CIGS DO FORM. LIGHT E/LT AND VRB WINDS TONIGHT WILL BECOME ENE 5-8KTS AFTER 15Z. /15/ PREV DISCUSSION... /ISSUED 356 PM CDT SUN SEP 27 2015/ DISCUSSION... AIR TEMPS ARE IN THE MID TO UPPER 80S LAST HOUR WITH SOME VARIABLE WINDS...BUT MOSTLY NE WINDS 5 TO 15 MPH. OUR 88D RADAR IS SHOWING A GOOD BOUNDARY LOW LEVEL FORCING OR COOL POOL OF 70S IF YOUR WILL TO OUR SOUTH...MIXING WARMER AS IT MOVES NW. A FEW SHOWERS IN OUR AREA ARE OVER DEEP EAST TEXAS AND SOME BETTER COVERAGE OF SHOWERS OVER TOLEDO BEND MOVING NW IN SAM RAYBURN. THE CORE OF THE UPPER LOW IS OVER THE TEXAS COASTAL BEND...ELONGATING OVER THE COAST. VERY HEAVY RAIN SHOWERS ARE PILING INTO THE SABINE PASS. WE WILL KEEP ON AN EYE ON THIS PROGRESS INTO THE EVENING HOURS. VISIBLE SATELLITE HAS A GREAT DEAL MORE PANCAKING CUMULUS ALONG I-30 NOW UNDER THE WARM NOSE...WHILE MULTI DECKS ARE PILING INTO THE I-20 CORRIDOR ERODING THE CAP. IT WILL BE INTERESTING TO SEE OUR NEXT SOUNDING. THE UPPER LOW THAT WAS OVER SW OKLAHOMA YESTERDAY IS NOW PRETTY MUCH THE NEW BASE OF THE TROUGH IN THE WEST GULF AS UNFOLDING PATTERN REMAINS AT THIS TIME. THE MODELS CLOSE OFF THE LOW TONIGHT WITH REALLY GOOD AGREEMENT AROUND 5780M OR SO FOR THE 500 MB LEVEL. SOME NOCTURNAL COVERAGE MAY BE POSSIBLE AROUND THE CORE WHICH COULD BRUSH OUR SOUTHERN TIER WITH CONVERGENCE DEVELOPING THE LOWER LEVELS. AS LONG AS THE UPPER LOW KEEPS WRAPPING UP TO THE SOUTHWEST...THE TROPICAL MOISTURE WILL PILE IN...AND ERODED THE CAP. FORCING IS FAIR TO DECENT WITH A DEEPENING SOUTHEAST FLOW BOUND TO BE PRODUCTIVE SOMEWHERE...EVEN UNDER THE INVERSION IF IT CAN BE LIFTED. SO WE HAVE KEPT POPS IN THE OVERNIGHT WITH HRRR MODEL SPOTTY ALONG AND SOUTH OF I-20 WITH SOME ISOLATED EVEN ALONG I-30. ALL THE MODELS AND WPC QPF LOOK ENCOURAGING. THE OVER RAIN CHANCE LOOKS FAIR TO AWESOME FOR A LUCKY FEW AT LEAST. HOPEFULLY...AS THE LOW WORKS BACK NORTHEASTWARD OVER THE AREA WE CAN MAKE MOST OF THAT NOCTURNAL WINDOW OF OPPORTUNITY. WE HAVE SLIGHT TO HIGH CHANCE POPS FOR MUCH OF THE AREA ALONG AND SOUTH OF I-20 FOR THE NEXT DAY OR TWO AS THE LOW WRAPS UP. THE FLY IN THE OINTMENT IS THE DRY SLOT AND ALL THE DRY AIR OVER THE WESTERN GULF WHICH IS SCOURING OUT THE GOOD TROPICAL MOISTURE IN THE MID AND UPPER LEVELS. THE WATER VAPOR WILL BE INDICATIVE AS THE SURFACE FLOW TRIES TO HANG ON TO NE WINDS. OUR 88D VAD IS SHOWING ENE TO 7KFT AND THEN ALL SOUTHEAST ALOFT...HOWEVER MAINTAINING RIGHT AT THAT CAP THIS AFTERNOON. SOMEWHAT OF AN OVERRUNNING PRECIP TYPE MAY UNFOLD IF THE CAP ERODES WITH ONLY A SHALLOW NE SFC FLOW LEFT DURING THE OVERNIGHT HOURS...THUS THE LUCKY FEW AT LEAST. OUR HOPE IS TO JUST GO AHEAD BLOW THE DRIEST MONTH RECORD AND SEE THE WPC QPF AND MORE AS THE WARM AND DRY WEATHER WILL RETURN TO THE FOUR STATE AREA ALL TO SOON BY MIDWEEK. /24/ && .PRELIMINARY POINT TEMPS/POPS... SHV 70 87 70 87 / 30 50 30 50 MLU 70 85 69 86 / 40 60 30 50 DEQ 65 86 67 86 / 20 20 20 40 TXK 67 85 68 85 / 20 40 30 40 ELD 66 84 66 84 / 30 50 30 50 TYR 69 87 69 87 / 20 40 20 40 GGG 68 86 69 88 / 20 40 30 40 LFK 67 85 69 87 / 30 50 30 40 && .SHV WATCHES/WARNINGS/ADVISORIES... AR...NONE. LA...NONE. OK...NONE. TX...NONE. && $$
AREA FORECAST DISCUSSION...UPDATED
NWS SHREVEPORT LA
703 PM CDT SUN SEP 27 2015 .AVIATION... EXTENSIVE ELEVATED CLOUD COVER IS IN PLACE ACROSS THE REGION THIS EVENING...WITH THIS WRAP-AROUND MOISTURE LINGERING NEAR AND N OF A CLOSED UPPER LOW ALONG THE SE TX COAST. THIS CLOUD COVER WILL PERSIST THROUGH MUCH OF THE TAF PERIOD...AS THE LOW REMAINS NEARLY STATIONARY ALONG THE COAST. AN EXTENSIVE AREA OF SHRA WITH EMBEDDED TSRA OFFSHORE NEAR THE CENTER OF THE SFC CIRCULATION ABOUT 100NM S OF SABINE PASS...SHOULD CONTINUE TO SLOWLY SPREAD NNW MAINLY INTO DEEP E TX/LOWER TOLEDO BEND COUNTRY OF WCNTRL LA THIS EVENING...PRIMARILY AFFECTING THE E TX TERMINALS OVERNIGHT. HAVE TEMPOED MENTION OF SHRA FOR THIS AREA FROM MID-EVENING THROUGH A PORTION OF THE OVERNIGHT HOURS FOR LFK ONLY...WITH MENTION OF VCSH FOR TYR/GGG LATE...ALTHOUGH ISOLATED -SHRA CAN/T BE RULED OUT OVER NW LA TONIGHT. HOWEVER...GIVEN THE ELEVATED CIGS AND VERY LIGHT NATURE OF THE RAIN...HAVE NOT MENTIONED VCSH FOR SHV ATTM. DRY SLOTTING ON THE E SIDE OF THE UPPER LOW OVER ECNTRL LA SHOULD LIMIT THE EXTENT OF SHRA DEVELOPMENT OVER THIS AREA THROUGH MONDAY AFTERNOON...WITH SCT SHRA POSSIBLE FARTHER W OVER WRN LA/E TX/SW AR NEAR THE ATTENDENT UPPER TROUGH AXIS. COULD ALSO SEE IFR/LOW MVFR CIGS DEVELOP/SPREAD W INTO SCNTRL AR/NCNTRL LA BY/AFTER 12Z MONDAY...AS WELL AS NEAR LFK...CLOSER TO THE RAIN AREA AS THE AIR MASS CONTINUES TO SATURATE. SHOULD SEE A SLOW IMPROVEMENT TO VFR CIGS BY MIDDAY MONDAY WHERE THE LOW CIGS DO FORM. LIGHT E/LT AND VRB WINDS TONIGHT WILL BECOME ENE 5-8KTS AFTER 15Z. /15/ && .PREV DISCUSSION... /ISSUED 356 PM CDT SUN SEP 27 2015/ DISCUSSION... AIR TEMPS ARE IN THE MID TO UPPER 80S LAST HOUR WITH SOME VARIABLE WINDS...BUT MOSTLY NE WINDS 5 TO 15 MPH. OUR 88D RADAR IS SHOWING A GOOD BOUNDARY LOW LEVEL FORCING OR COOL POOL OF 70S IF YOUR WILL TO OUR SOUTH...MIXING WARMER AS IT MOVES NW. A FEW SHOWERS IN OUR AREA ARE OVER DEEP EAST TEXAS AND SOME BETTER COVERAGE OF SHOWERS OVER TOLEDO BEND MOVING NW IN SAM RAYBURN. THE CORE OF THE UPPER LOW IS OVER THE TEXAS COASTAL BEND...ELONGATING OVER THE COAST. VERY HEAVY RAIN SHOWERS ARE PILING INTO THE SABINE PASS. WE WILL KEEP ON AN EYE ON THIS PROGRESS INTO THE EVENING HOURS. VISIBLE SATELLITE HAS A GREAT DEAL MORE PANCAKING CUMULUS ALONG I-30 NOW UNDER THE WARM NOSE...WHILE MULTI DECKS ARE PILING INTO THE I-20 CORRIDOR ERODING THE CAP. IT WILL BE INTERESTING TO SEE OUR NEXT SOUNDING. THE UPPER LOW THAT WAS OVER SW OKLAHOMA YESTERDAY IS NOW PRETTY MUCH THE NEW BASE OF THE TROUGH IN THE WEST GULF AS UNFOLDING PATTERN REMAINS AT THIS TIME. THE MODELS CLOSE OFF THE LOW TONIGHT WITH REALLY GOOD AGREEMENT AROUND 5780M OR SO FOR THE 500 MB LEVEL. SOME NOCTURNAL COVERAGE MAY BE POSSIBLE AROUND THE CORE WHICH COULD BRUSH OUR SOUTHERN TIER WITH CONVERGENCE DEVELOPING THE LOWER LEVELS. AS LONG AS THE UPPER LOW KEEPS WRAPPING UP TO THE SOUTHWEST...THE TROPICAL MOISTURE WILL PILE IN...AND ERODED THE CAP. FORCING IS FAIR TO DECENT WITH A DEEPENING SOUTHEAST FLOW BOUND TO BE PRODUCTIVE SOMEWHERE...EVEN UNDER THE INVERSION IF IT CAN BE LIFTED. SO WE HAVE KEPT POPS IN THE OVERNIGHT WITH HRRR MODEL SPOTTY ALONG AND SOUTH OF I-20 WITH SOME ISOLATED EVEN ALONG I-30. ALL THE MODELS AND WPC QPF LOOK ENCOURAGING. THE OVER RAIN CHANCE LOOKS FAIR TO AWESOME FOR A LUCKY FEW AT LEAST. HOPEFULLY...AS THE LOW WORKS BACK NORTHEASTWARD OVER THE AREA WE CAN MAKE MOST OF THAT NOCTURNAL WINDOW OF OPPORTUNITY. WE HAVE SLIGHT TO HIGH CHANCE POPS FOR MUCH OF THE AREA ALONG AND SOUTH OF I-20 FOR THE NEXT DAY OR TWO AS THE LOW WRAPS UP. THE FLY IN THE OINTMENT IS THE DRY SLOT AND ALL THE DRY AIR OVER THE WESTERN GULF WHICH IS SCOURING OUT THE GOOD TROPICAL MOISTURE IN THE MID AND UPPER LEVELS. THE WATER VAPOR WILL BE INDICATIVE AS THE SURFACE FLOW TRIES TO HANG ON TO NE WINDS. OUR 88D VAD IS SHOWING ENE TO 7KFT AND THEN ALL SOUTHEAST ALOFT...HOWEVER MAINTAINING RIGHT AT THAT CAP THIS AFTERNOON. SOMEWHAT OF AN OVERRUNNING PRECIP TYPE MAY UNFOLD IF THE CAP ERODES WITH ONLY A SHALLOW NE SFC FLOW LEFT DURING THE OVERNIGHT HOURS...THUS THE LUCKY FEW AT LEAST. OUR HOPE IS TO JUST GO AHEAD BLOW THE DRIEST MONTH RECORD AND SEE THE WPC QPF AND MORE AS THE WARM AND DRY WEATHER WILL RETURN TO THE FOUR STATE AREA ALL TO SOON BY MIDWEEK. /24/ && .PRELIMINARY POINT TEMPS/POPS... SHV 70 87 70 87 / 30 50 30 50 MLU 70 85 69 86 / 30 60 30 50 DEQ 65 86 67 86 / 10 20 20 40 TXK 67 85 68 85 / 20 40 30 40 ELD 66 84 66 84 / 30 50 30 50 TYR 69 87 69 87 / 20 40 20 40 GGG 68 86 69 88 / 20 40 30 40 LFK 67 85 69 87 / 40 50 30 40 && .SHV WATCHES/WARNINGS/ADVISORIES... AR...NONE. LA...NONE. OK...NONE. TX...NONE. && $$ 15
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
830 PM EDT SUN SEP 27 2015 .SYNOPSIS... HIGH PRESSURE WILL MOVE OFF THE NEW ENGLAND COAST THROUGH TUESDAY WHILE AND EASTERLY FLOW CONTINUES OVER THE AREA. A COLD FRONT WILL PASS THROUGH THE AREA TUESDAY NIGHT INTO WEDNESDAY. LOW PRESSURE WILL DEVELOP ALONG THE BOUNDARY TO OUR SOUTH...POSSIBLY IMPACTING THE AREA DURING THE LATTER PORTION OF NEXT WEEK. && .NEAR TERM /THROUGH MONDAY/... HIGH PRESSURE WILL SLOWLY MOVE OFF THE NEW ENGLAND COAST TONIGHT. MOISTURE WILL INCREASE FROM SOUTH TO NORTH. THERE MAY BE SOME BREAKS IN THE CLOUDS THIS EVENING...ESPECIALLY ACROSS THE WASHINGTON AND BALTIMORE METROPOLITAN AREAS TO THE MARYLAND CHESAPEAKE BAY. THIS IS BECAUSE DAYTIME MIXING WILL HAVE DISSIPATED AND THE DEEPER MOISTURE SHOULD STILL BE TO THE SOUTH. AS MOISTURE INCREASES OVERNIGHT...PLENTY OF LOW CLOUDS ARE EXPECTED. PATCHY DRIZZLE IS POSSIBLE TOWARD MORNING...ESPECIALLY OVER THE HIGHER TERRAIN. MODEL SOUNDINGS FROM BOTH THE NAM AND GFS AS WELL AS LAMP MODEL CLOUD CEILINGS ALL SHOW CLOUDS LOWERING OVERNIGHT. BASED ON RADAR OBS AND HRRR SHORT RANGE FORECAST... INCLUDED SCT SHOWERS FOR E WV W MD AND W CENTRAL VA...ISOLATED SHOWERS EAST TO CENTRAL MD AND NOVA...AND KEPT IT DRY FOR THE OVERNIGHT FOR THE EAST. AN EAST TO SOUTHEAST FLOW WILL CONTINUE MONDAY AROUND THE DEPARTING HIGH. POPUP SHOWERS ARE EXPECTED POSSIBLE LATER MONDAY MORNING THROUGH MONDAY AFTERNOON ACROSS ALL LOCATIONS. AN ISOLATED THUNDERSTORM CANNOT BE RULED OUT...ESPECIALLY IF THERE ARE SOME MORE BREAKS OF SUNSHINE THEN CURRENTLY ANTICIPATED. MONDAY WILL TURN OUT WARMER AND NOTICEABLY MORE HUMID WITH MAX TEMPS IN THE UPPER 70S TO LOWER 80S NEAR WASHINGTON AND BALTIMORE. && .SHORT TERM /MONDAY NIGHT THROUGH TUESDAY NIGHT/... A SOUTHEAST FLOW WILL CONTINUE TO USHER IN PLENTY OF MOISTURE MONDAY NIGHT. WARM AND HUMID CONDITIONS ARE EXPECTED ALONG WITH LOW CLOUDS AND AREAS OF FOG. LOCALLY DENSE FOG IS EXPECTED ACROSS THE HIGHER TERRAIN. MORE SHOWERS ARE POSSIBLE AS WELL DUE TO THE DEEP MOISTURE AND A STRENGTHENING LOW-LEVEL WIND FIELD. TUESDAY...UPR LOW/TROUGH EJECTS NE FROM TX. MEANWHILE AN UPR TROUGH SWINGS EAST ACROSS THE NRN GREAT LAKES AND THE SFC TROUGH AMPLIFIES UP THE MID-ATLANTIC COAST. THE SFC HIGH WEDGE IS EXPECTED TO DIMINISH THROUGH THE DAY WITH SFC WINDS SHIFTING FROM NELY TO SELY...PARTICULARLY ALONG THE COAST. THINKING A DIURNAL TREND IN POPS WITH CHANCES IN THE MORNING AND LIKELIES IN THE AFTERNOON AND EVENING. ELEVATED SKINNY INSTABILITY WARRANTS LOW CHANCES FOR THUNDER LATE MORNING INTO THE EVENING. TUESDAY NIGHT...12Z GFS AND ECMWF DEVELOP A WEAK COASTAL FLOW OVER THE DELMARVA BY LATE IN THE NIGHT. THIS WOULD SHIFT WINDS TO NWLY AND INCREASE ELEVATED LIFT. LOWERED POPS TO CHC THROUGH THE NIGHT...BUT ONGOING RAIN (POSSIBLY HEAVY AT TIMES) MAY LAST ALL NIGHT. SHORT TERM GUIDANCE HAS HAD DIFFICULTY OVER THE PAST FEW DAYS...SO CONFIDENCE IN TUESDAY NIGHT IS STILL LOWER THAN NORMAL. THAT SAID...WITH ENSEMBLES SHOWING HIGH PRECIPITABLE WATER AND A BOUNDARY MOVING THROUGH...WE HAVE MENTIONED A POTENTIAL FOR HEAVY RAIN AND FLOODING IN OUR HAZARDOUS WEATHER OUTLOOK AND WPC HAS MUCH OF OUR AREA IN THEIR EXCESSIVE RAINFALL DISCUSSION FOR TUE. && .LONG TERM /WEDNESDAY THROUGH SUNDAY/... AN UPPER-LEVEL TROUGH AXIS WILL REMAIN OVER THE REGION DURING THE SECOND HALF OF THE WEEK. MEANWHILE AT THE SURFACE...A COLD FRONT WILL STALL JUST SOUTHEAST OF THE AREA. THIS WILL TEND TO KEEP CLOUDS AND THE POTENTIAL FOR PERIODS OF RAIN OVER THE AREA. IT DOES NOT LOOK LIKE A COMPLETE WASH OUT BUT THERE SHOULD BE AT LEAST ONE OR TWO PERIODS OF RAIN DURING THE WEDNESDAY-FRIDAY TIMEFRAME. THE LATEST GUIDANCE HAS ALMOST UNANIMOUSLY SHIFTED WESTWARD AND DEEPER WITH AN UPPER-TROUGH/EVENTUAL CUTOFF LOW THAT APPROACHES THE MID-ATLANTIC BY THE END OF THE WEEK AND INTO THE WEEKEND...THANKS IN LARGE PART TO A PERSISTENT BLOCKING HIGH OVER SOUTHEASTERN CANADA. TRENDED SKY COVER AND POPS UP A BIT BUT DID NOT GO ABOVE CHANCE GIVEN THERE IS STILL SPREAD ON THE AMPLITUDE OF THE TROUGH AND THE WESTWARD SHIFT WAS ONLY JUST NOTED AFTER THE LAST MODEL CYCLE OR TWO. POTENTIAL DOES EXIST HOWEVER FOR A PERIOD OF SOAKING...WIND- DRIVEN RAIN. TEMPERATURES LOOK TO BE BELOW NORMAL DURING THE SECOND HALF OF THE WEEK AS NORTHERLY TO NORTHEASTERLY FLOW ORIGINATING FROM COOL HIGH PRESSURE OVER CANADA PERSISTS. && .AVIATION /00Z MONDAY THROUGH FRIDAY/... LIFR TO IFR LOW CLOUDS ARE EXPECTED TO DEVELOP ACROSS MUCH OF THE AREA LATE TONIGHT INTO MONDAY MORNING. CIGS ARE EXPECTED TO LIFT A BIT MONDAY AFTERNOON...BUT SCATTERED SHOWERS ARE POSSIBLE AS WELL. AN ISOLATED THUNDERSTORM CANNOT BE RULED OUT DURING THE AFTERNOON AND EVENING HOURS. WIDESPREAD LOW CLOUDS AND AREAS OF FOG ARE EXPECTED MONDAY NIGHT. MAINLY VFR/MVFR CIGS TUESDAY AS NELY FLOW VEERS SELY. LIKELY RAIN WITH MVFR VSBY EXPECTED IN MODERATE INTENSITY. LOW CHANCES FOR THUNDER DEVELOPS THROUGH THE DAY AS LOW PRESSURE DEVELOPS OVER DELMARVA. RAIN AND REDUCED FLIGHT CONDITIONS CONTINUES INTO THE NIGHT...POSSIBLY THROUGH THE NIGHT. SUB-VFR PSBL IN LOW CIGS/PDS OF -RA WED-THU. NLY FLOW 10-15 KT. && .MARINE... HIGH PRESSURE WILL MOVE OFF THE NEW ENGLAND COAST BUT IT WILL REMAIN CLOSE ENOUGH TO KEEP AN EASTERLY FLOW OVER THE AREA. A SMALL CRAFT ADVISORY IS IN EFFECT FOR THE S BAY AND LOWER POTOMAC UNTIL MIDNIGHT WHERE GUSTS HAVE BEEN AROUND 20 KT. THE GRADIENT CONTINUES TO SLOWLY WEAKEN...SO HAVE WINDS BELOW ADVISORY LEVELS AFTER MIDNIGHT. HOWEVER...WIND GUSTS MAY COME CLOSE TO SCA CRITERIA FOR PORTIONS OF THE BAY AND LOWER TIDAL POTOMAC RIVER. ONSHORE FLOW CONTINUES TUESDAY...THOUGH GUSTS LOOK TO BE 15 KT MAX. WIND SHIFTS NORTHERLY TUESDAY NIGHT AS LOW PRESSURE PASSES. GUSTS AROUND 20 KT IN A DECENT PRESSURE GRADIENT WITH SCA LIKELY FOR MOST WATERS. PERSISTENT NORTHEASTERLY WINDS IN A GRADIENT BETWEEN STRONG HIGH PRESSURE TO THE NORTH AND WAVES OF LOW PRESSURE PASSING TO THE SOUTH WILL LIKELY RESULT IN WIND GUSTS AT OR ABOVE SMALL CRAFT ADVISORY FOR PORTIONS OF THE WATERS DURING MUCH OF THE SECOND HALF OF THE WEEK. && .TIDES/COASTAL FLOODING... TIDES ARE CONTINUING TO RUN A FOOT TO A FOOT AND A HALF ABOVE NORMAL WITH THE EAST WINDS. EXPECT THE NEXT SEVERAL HIGH TIDES TO BE SIMILAR WITH MANY AREAS EXPERIENCING MINOR TIDAL FLOODING AROUND HIGH TIDE TIMES. STRAITS POINT IN ST MARYS COUNTY IS THE ONE GAUGE THAT WILL BE FLIRTING WITH MODERATE FLOODING THAT WOULD NECESSITATE A WARNING...INSTEAD OF THE ADVISORY THAT COVERS MOST OF OUR TIDAL SHORES. AT THIS POINT THOUGH...SINCE LOW TIDE AT STRAITS CAME IN A LITTLE LOWER THERE THAN THE LAST...EXPECT HIGH TIDE TO BE JUST UNDER THE MODERATE THRESHOLD. WINDS EASE AND TURN NLY ON THE WATERS TUESDAY NIGHT...WITH WATER LEVEL ANOMALIES DECREASING. THE PATTERN WITH A BLOCKING HIGH PRESSURE TO THE NORTH AND WAVES OF LOW PRESSURE PASSING TO THE SOUTH MAY RESULT IN PERIODIC COASTAL FLOODING DURING MUCH OF THE SECOND HALF OF THE WEEK. ULTIMATELY IT WILL DEPEND ON WHETHER THE WIND TAKES ON A MORE NORTHERLY COMPONENT (DRIVING WATER OUT OF THE BAY WITH LESS RISK FOR FLOODING) OR EASTERLY COMPONENT (KEEPING WATER PILED UP ALONG THE SHORE AND INCREASING THE RISK OF FLOODING). && .LWX WATCHES/WARNINGS/ADVISORIES... DC...COASTAL FLOOD ADVISORY UNTIL 6 AM EDT MONDAY FOR DCZ001. MD...COASTAL FLOOD ADVISORY UNTIL 6 AM EDT MONDAY FOR MDZ011-013- 014-017-018. VA...COASTAL FLOOD ADVISORY UNTIL 6 AM EDT MONDAY FOR VAZ053-054. WV...NONE. MARINE...COASTAL FLOOD ADVISORY UNTIL 6 AM EDT MONDAY FOR ANZ535-538- 542. SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR ANZ533-534- 537-543. && $$ SYNOPSIS...BJL NEAR TERM...BJL/CAS SHORT TERM...BAJ/BJL/CAS LONG TERM...BAJ/BJL/DFH AVIATION...BAJ/BJL/CAS/DFH MARINE...BAJ/BJL/CAS/DFH TIDES/COASTAL FLOODING...CAS/BJL/BAJ
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1159 PM EDT SUN SEP 27 2015 .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 412 PM EDT SUN SEP 27 2015 WATER VAPOR IMAGERY AND RAP ANALYSIS SHOW A MID/UPPER RIDGE EXTENDING FROM THE DESERT SW TO SE CANADA WHILE A TROF IS PROGRESSING THRU WRN CANADA. AT THE SFC...THE TROF IS SUPPORTING A COLD FRONT EXTENDING FROM CNTRL SD ACROSS FAR NW MN TO HUDSON BAY. SW FLOW BTWN THE COLD FRONT AND SFC HIGH PRES CENTERED JUST OFF THE NEW ENGLAND COAST HAS LED TO ANOTHER UNSEASONABLY WARM LATE SEPT DAY TODAY. TEMPS ARE CURRENTLY WELL INTO THE 70S ACROSS MOST OF UPPER MI WITH A FEW LOCATIONS...MAINLY IN THE DOWNSLOPE AREAS NEAR LAKE SUPERIOR...AROUND 80F. FOG/STRATUS THAT WAS OVER CNTRL UPPER MI EARLY THIS MORNING BURNED OFF BY LATE MORNING. STRATOCU THAT WAS OVER IL/SE WI/LAKE MI EARLY TODAY HAS SPREAD N. WHILE STILL S OF KMNM...THE AREA OF MOISTURE HAS LED TO MORE CLOUD COVER FROM AROUND KISQ/KERY EASTWARD. OTHERWISE...SKIES ARE MOSTLY SUNNY. DURING THE SHORT TERM...FOCUS WILL BE ON CLOUD TRENDS THIS EVENING FOR VIEWING LUNAR ECLIPSE AND THEN PCPN POTENTIAL AS WRN CANADA TROF CONTINUES EASTWARD...PUSHING SFC COLD FRONT ACROSS THE AREA MON. WITH COLD FRONT APPROACHING...MODELS SHOW WINDS IN THE APPROACHING CLOUD BEARING LAYER (ROUGHLY 875-850MB) VEERING SOME TONIGHT. THUS...THE DIRECTION OF MOVEMENT OF THE STRATOCU APPROACHING FROM S SHOULD TEND TO TAKE ON MORE OF AN EASTERLY COMPONENT WITH TIME. AT THIS POINT...IT APPEARS LOCATIONS ROUGHLY EAST OF AN IRON MTN TO MUNISING LINE WILL HAVE THE MOST CLOUD COVER...POTENTIALLY OBSCURING MUCH OF THE LUNAR ECLIPSE THIS EVENING AT A FEW LOCATIONS. NAM IN PARTICULAR IS AGGRESSIVE IN MOISTENING LOWER LEVELS BLO STRATOCU LAYER FARTHER TO THE W...BUT DON`T THINK THIS WILL TRANSLATE TO LOW CLOUD DEVELOPMENT THIS EVENING EVEN IF IT IS CORRECT WITH THE MOISTURE. ATTENTION THEN TURNS TO APPROACHING COLD FRONT. THERE ARE ONLY VERY MINOR DIFFERENCES IN THE MODELS IN TIMING FRONT ACROSS THE AREA... REACHING THE W EARLY MON MORNING AND EXITING THE SE LATE AFTN. GUIDANCE SUPPORTS SCT/CHC POPS LATE TONIGHT OVER THE W. BIGGER UNCERTAINTY CONTINUES TO BE WHETHER THE UPPER JET CONFIGURATION WITH RIGHT ENTRANCE UPPER DIVERGENCE AND LOW/MID LEVEL FGEN UNDERNEATH WILL BE SUFFICENT TO HELP DEVELOP A HEAVIER/MORE SOLID BAND OF SHRA JUST BEHIND THE FRONT AS IT MOVES SE ACROSS THE AREA MON. THE MAJORITY OF GUIDANCE SUPPORTS THE IDEA OF IMPROVED FORCING LEADING TO AN INCREASE IN SHRA COVERAGE ACROSS AT LEAST THE SCNTRL AND ERN FCST AREA MON AFTN. WITH THE LAST FEW HRS OF THE LATEST RAP RUN ENDING AT 12Z MON APPEARING TO SUPPORT THAT IDEA AS IT HAS STRONGER FORCING DEVELOPING TO THE W AT THE END OF THE MODEL RUN...WILL RAISE POPS FOR MON...ESPECIALLY SCNTRL AND E WHERE LIKELY/NMRS WILL BE UTILIZED LATE. NOT OUT OF THE QUESTION THAT THERE COULD BE A FEW RUMBLES OF THUNDER...BUT POTENTIAL IS TOO LOW AT THIS POINT TO INCLUDE MENTION. .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 158 PM EDT SUN SEP 27 2015 AN UPPER TROUGH WILL BE BEARING DOWN ON THE AREA MON NIGHT...BUT AN EMBEDDED SHORTWAVE TROUGH WILL BE THE FOCUS FOR SOME SHOWERS THAT MAY GRAZE FAR SERN UPPER MI IN THE FEW FEW HOURS AFTER 00Z TUE. THESE SHOWERS WILL QUICKLY EXIT AS SFC HIGH PRESSURE MOVES IN FROM THE W AND THE UPPER TROUGH AXIS MOVES OVERHEAD ON TUE. 18Z 850MB TEMPS WILL BE NEAR OR BELOW 0C...WHICH WILL MAKE FOR HIGHS IN THE MID 50S TO AROUND 60. NW WINDS GUSTING TO 20-25MPH NEAR LAKE SUPERIOR AND E WILL MAKE THAT FEEL A BIT CHILLIER. WILL INCREASE CLOUD COVER OVER THE E NEAR LAKE SUPERIOR AS LAKE EFFECT CLOUDS SHOULD RESULT...BUT WILL ALSO SHOW CLOUDS DECREASING IN THE AFTERNOON AS HIGH AIR CONTINUES TO INTRUDE. THE SFC HIGH MOVES OVER TUE NIGHT AS 850MB TEMPS REMAIN AROUND 0C. PWATS DROP TO AROUND 0.25 INCHES AND WINDS WILL BE LIGHT...SO RADIATIONAL COOLING AFTER AN ALREADY COOL DAY WILL MAKE FOR VERY COLD LOW TEMPS MAINLY IN THE 20S AND 30S...COLDEST INTERIOR OF COURSE. WILL NOT MAKE SIGNIFICANT CHANGES TO THE GOING FORECAST AS VALUES ARE ON THE LOW END OF GUIDANCE...WHICH LOOKS GOOD. FROST APPEARS LIKELY FOR MUCH OF THE AREA...EVEN SOME SHORELINE AREAS. THE HIGH WILL MOVE E ON WED...AS WILL THE 850MB THERMAL TROUGH...ALLOWING FOR 1-2 DEGREE WARMER MAX TEMPS THAN ON TUE...HIGHS AROUND 60. CONTINUED TO NOTE WHAT THE PREVIOUS SHIFT SAW IN MODEL TRENDS...DRYER WEATHER FOR THE LAST HALF OF THE WEEK. CAN NOT BE TOO CONFIDENT...THOUGH...GIVEN VERY POOR RUN TO RUN CONTINUITY IN THE PATTERN OVER THE LAST FEW MODEL RUNS. WILL CONTINUE TO RELY ON CONSENSUS GUIDANCE...WHICH WILL TREND THE FORECAST DRYER. TEMPS LOOK TO TOP OUT IN THE 60S FOR THE LAST HALF. MIN TEMPS WILL BE TRICKIER GIVEN THE GREATER RELIANCE ON CLOUD COVER...WHICH IS QUITE UNCERTAIN...BUT IT LOOKS LIKE WED NIGHT WILL BE COLDEST WITH LOWS POSSIBLY IN THE MID TO UPPER 30S INLAND AND WARMER NEAR THE SHORE. COULD SEE SOME PATCHY FROST WED NIGHT...BUT WILL HAVE TO GET CLOSER BEFORE ADDING THAT TO THE FORECAST. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 1150 PM EDT SUN SEP 27 2015 VFR CONDITIONS WILL GRADUALLY GIVE WAY TO MVFR CIGS AND SCATTERED SHOWERS LATE TONIGHT INTO EARLY MONDAY MORNING AND LATE MON MORNING AT KSAW ALONG/AHEAD OF AN ADVANCING COLD FRONT. SHOWERS WILL ONLY LAST A FEW HOURS AT EACH TERMINAL WITH IMPROVING CONDITIONS FROM THE WEST THROUGH THE DAY ON MONDAY AS NW WINDS BRING DRIER AIR INTO THE REGION. LLWS IS EXPECTED AT ALL SITES THROUGH AT LEAST 12Z MON. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 412 PM EDT SUN SEP 27 2015 AHEAD OF AN APPROACHING COLD FRONT...S TO SW WINDS ACROSS LAKE SUPERIOR WILL GUST TO AROUND 25KT TONIGHT...BUT UP TO 30KT AT THE HIGHEST OBS PLATFORMS. THE FRONT WILL CROSS LAKE SUPERIOR LATE TONIGHT AND MON...BRINGING A WIND SHIFT TO THE W TO NW WITH SPEEDS GENERALLY UNDER 20KT. AN UPTICK IN WINDS IS EXPECTED MON NIGHT/TUE TO 20-30KT...ESPECIALLY OVER CNTRL AND EASTERN LAKE SUPERIOR AS INSTABILITY INCREASES WITH INCREASINGLY COLDER AIR FLOWING OVER THE LAKE AHEAD OF APPROACHING HIGH PRES. WINDS WILL THEN DIMINISH TO UNDER 15KT W TO E TUE NIGHT AS HIGH PRES SETTLES OVER THE UPPER LAKES. THE HIGH PRES WILL THEN DRIFT TO THE ENE WED THRU FRI...BUT WILL MAINTAIN RIDGING BACK INTO THE UPPER LAKES. AS A RESULT...WHILE WINDS WILL INCREASE SOME...SPEEDS SHOULD REMAIN MOSTLY 20KT OR LESS DURING THE LAST HALF OF THE WEEK. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...ROLFSON LONG TERM...TITUS AVIATION...VOSS MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS GAYLORD MI
1011 PM EDT SUN SEP 27 2015 .UPDATE... ISSUED AT 1011 PM EDT SUN SEP 27 2015 LOW CLOUDS (UNFORTUNATELY) CONTINUE TO HANG OVER ALMOST ALL OF OUR CWA LATE THIS EVENING...WITH THE EXCEPTION OF FAR WRN SECTIONS OF CHIPPEWA AND MACKINAC COUNTIES RIGHT ALONG THE NW EDGE OF THIS LOW CLOUD DECK. BAD TIMING TO HAVE A CLOUDY NIGHT GIVEN THE RARE SUPERMOON LUNAR ECLIPSE HAPPENING AS I WRITE. EXPECT THESE CLOUDS WILL REMAIN IN PLACE ALL NIGHT. A FEW REGION OBS HAVE ACTUALLY REPORTED SOME VERY LIGHT SHOWER ACTIVITY...AND HAVE ADDED THIS TO THE FORECAST FOR THE BALANCE OF THE NIGHT. BOTH THE LATEST RAP13 AND HRRR SUPPORT THIS NOTION. TEMPS WILL ONLY FALL A FEW DEGREES AS WE HEAD INTO THE OVERNIGHT HOURS...WITH LOW TEMPS COOLING INTO THE UPPER 50S AND LOWER 60S. && .NEAR TERM...(THIS EVENING THROUGH TONIGHT) ISSUED AT 414 PM EDT SUN SEP 27 2015 ...SORRY FOR THE CLOUDS LUNAR ECLIPSE VIEWERS... MID LEVEL MOISTURE CONTINUES TO STREAM NORTHWARD INTO NORTHERN MICHIGAN. THIS HAS RESULTED IN MOSTLY CLOUDY SKIES ACROSS THE REGION AS EXPECTED. HOWEVER THERE IS AT LEAST A LITTLE HOPE ON THE HORIZON AS SATELLITE IMAGERY DOES SHOW A FEW HOLES IN THE CLOUD COVER UPSTREAM. SO ALTHOUGH IT MAY BE TOUGH TO SEE THE LUNAR ECLIPSE...A FEW OCCASIONAL GLIMPSES ARE STILL POSSIBLE AT TIMES THIS EVENING...DESPITE THE ABUNDANT CLOUD COVER. THERE ARE QUESTIONS OVERNIGHT ABOUT THE EXTENT OF CLOUD COVER AS MOISTURE BEGINS TO DIMINISH (1000-500 MB RH FALLS FROM BETWEEN 60 AND 80 PERCENT TO BETWEEN 50 AND 70 PERCENT)...BUT ANY PARTIAL CLEARING WILL LIKELY LEAD TO AREAS OF STRATUS FORMATION. MILDER WITH SOUTH WINDS KEEPING LOWS IN THE UPPER 50S TO MIDDLE 60S. && .SHORT TERM...(MONDAY THROUGH WEDNESDAY) ISSUED AT 414 PM EDT SUN SEP 27 2015 ...HEADLINES.. HIGH IMPACT WEATHER POTENTIAL: NON-SEVERE CONVECTION MONDAY AFTERNOON/EVENING. FROST POSSIBLE WEDNESDAY MORNING. PATTERN SYNOPSIS/FORECAST: MAIN WESTERLIES DISPLACED WELL NORTH ACROSS CANADA...WITH WEAK UPPER LEVEL FLOW AND EMBEDDED DISTURBANCES ACROSS THE SOUTHERN/EASTERN CONTINENTAL U.S. NORTHERN PORTION OF A SPLITTING TROUGH CROSSING WESTERN/CENTRAL CANADA...WITH A PIECE OF ENERGY LEFT BEHIND AROUND 140W. MEANWHILE...DISTURBANCES CAUGHT IN WEAK FLOW INCLUDE ONE OVER TEXAS/WESTERN GULF OF MEXICO...A SUBTROPICAL DISTURBANCE SOUTH OF BERMUDA NEAR 60W...AND A WEAKENING FEATURE OVER THE MID ATLANTIC STATES. AT THE SURFACE...1034MB HIGH STRETCHING ACROSS NEW ENGLAND/NOVA SCOTIA RIDGING WEST INTO THE GREAT LAKES/OHIO VALLEY. PLENTY OF MOISTURE OVER THE SOUTHEAST QUADRANT OF THE COUNTRY...WITH 60S DEW POINTS/BOUNDARY LAYER MIXING RATIOS >10G/KG CREEPING AROUND THE PERIPHERY OF THE ANTICYCLONE AND INTO ILLINOIS/INDIANA/SOUTHWEST LOWER MICHIGAN. COLD FRONT EXTENDS FROM NORTHWEST ONTARIO INTO THE DAKOTAS/NORTHERN WYOMING. HEIGHT FALLS ASSOCIATED WITH THE SHORT WAVE TROUGH OVER WESTERN CANADA WILL HAVE THE BIGGEST SHORT TERM FORECAST IMPACT ON THE GREAT LAKES FOR THE EARLY PART OF THIS WEEK...AS SOUTHERN PORTION OF THIS WAVE WILL CLIP MICHIGAN IN THE MONDAY-TUESDAY TIME FRAME BEFORE LIFTING OUT BY MIDWEEK WITH THE POSSIBILITY OF ANOTHER WEAKNESS DEVELOPING OVER THE OHIO/TENNESSEE VALLEYS AND SOUTHEASTERN STATES BY THURSDAY. UPSTREAM COLD FRONT WILL ARRIVE ACROSS NORTHERN MICHIGAN MONDAY AFTERNOON...AND IS EXPECTED TO DROP INTO SOUTHERN LOWER MICHIGAN AFTER MIDNIGHT TUESDAY WITH DECENT COLD ADVECTION IN ITS WAKE. HIGH PRESSURE THEN BUILDS INTO MICHIGAN TUESDAY NIGHT/ WEDNESDAY. PRIMARY FORECAST CONCERNS: PRECIPITATION CHANCES/AMOUNTS WITH COLD FRONT MONDAY/MONDAY NIGHT...CHILLY TEMPERATURES WEDNESDAY MORNING? MONDAY...COLD FRONT NOT EXPECTED TO ARRIVE ACROSS EASTERN UPPER UNTIL MID AFTERNOON...BUT INCREASING LOW LEVEL MOISTURE AHEAD OF THE FRONT WITH DEW POINTS CLIMBING INTO THE LOWER-MID 60S. SOME INDICATIONS OF INSTABILITY DEVELOPING AHEAD OF THE FRONT ESPECIALLY IN THE NAM-WRF WHICH IS (AS USUAL) BULLISH ON PULLING HIGHER DEW POINTS INTO NORTHERN LOWER. THINK WHAT MAY OCCUR IS A MOSTLY POST- FRONTAL RAIN BAND MOVING INTO EASTERN UPPER DURING MID/LATE AFTERNOON...WHILE PRE-FRONTAL CONVECTION DEVELOPS ACROSS INTERIOR NORTHERN LOWER DURING THE AFTERNOON. POSSIBLE THAT FAR SOUTHWEST PORTIONS OF THE FORECAST AREA (MBL/FKS/TVC) MAY STAY DRY THROUGH THE AFTERNOON. ONE LAST WARM AFTERNOON EXPECTED WITH HIGHS IN THE 70S. RAIN BAND SHOULD THEN PROGRESS SOUTHWARD ACROSS NORTHERN MICHIGAN MONDAY NIGHT...AIDED BY RIGHT ENTRANCE REGION JET FORCING. RAIN SHOULD PUSH SOUTH OF THE UPPER PENINSULA DURING THE EARLY MORNING HOURS OF TUESDAY. GENERAL RAINFALL TOTALS OF 0.25-0.50 INCH EXPECTED THROUGH TUESDAY MORNING. TUESDAY...WILL BE FIRMLY IN POST-COLD FRONT AIR MASS TUESDAY MORNING...MOST OF THE PRECIPITATION SHOULD BE SOUTH OF THE FORECAST AREA BUT CAN`T RULE OUT SOME LINGERING SHOWERS ACROSS SOUTHEAST QUARTER OF THE FORECAST AREA ALLOWING FOR UNCERTAINTY IN FRONTAL SPEED. BUT SHOULD BE CLEARING OUT BEYOND THAT AS COOLER/DRIER AIR SPILL ACROSS NORTHERN MICHIGAN...AND MUCH COOLER THAN RECENT DAYS WITH HIGHS IN THE UPPER 50S-MID 60S EXPECTED WITH A NORTHWEST BREEZE. HIGH PRESSURE THEN BUILDS INTO MICHIGAN TUESDAY NIGHT ALONG WITH A FLATTENING PRESSURE GRADIENT. POSSIBILITY OF GOOD RADIATIONAL COOLING CONDITIONS MAY SET THE STAGE FOR A PRETTY GOOD FROST ACROSS INTERIOR EASTERN UPPER/NORTHERN LOWER MICHIGAN WEDNESDAY MORNING. WEDNESDAY...SURFACE HIGH PRESSURE WILL REMAIN IN CONTROL WEDNESDAY...SO ANOTHER NICE DAY ON TAP THOUGH TEMPERATURES WILL REMAIN A FEW DEGREES BELOW END OF SEPTEMBER NORMALS. && .LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY) ISSUED AT 414 PM EDT SUN SEP 27 2015 A FAIRLY QUIET EXTENDED PERIOD IS ON TAP ACROSS NORTHERN MICHIGAN AS SURFACE HIGH PRESSURE DOMINATES...PROVIDING DRY CONDITIONS AND COOLER TEMPERATURES THROUGH AT LEAST SATURDAY. RECENT TRENDS HAVE SLOWED NEXT WEEKEND`S DEVELOPMENT OF LOW PRESSURE OVER THE PLAINS BEFORE SLIDING NORTHEASTWARD TOWARD THE GREAT LAKES. AT THIS POINT...THERE`S FAIRLY LOW CONFIDENCE IN HOW THE DETAILS WILL PLAY OUT FOR THE END OF NEXT WEEKEND AS INTERACTIONS...FROM BOTH THE AFOREMENTIONED HIGH PRESSURE AND ANOTHER DEVELOPING LOW PRESSURE CENTER OVER THE EASTERN SEABOARD...REMAIN UNCLEAR. IT`S SAFE TO SAY THE AREA WILL RETURN TO TEMPERATURES MUCH MORE REPRESENTATIVE OF CLIMATOLOGICAL NORMAL FOR THE FIRST WEEK OF OCTOBER. HIGH TEMPS ARE EXPECTED TO RANGE FROM THE UPPER 50S TO LOWER 60S WITH LOWS IN THE 30S TO LOW 40S THROUGHOUT THE PERIOD. HAVE GONE AHEAD AND ADDED PATCHY FROST ON WEDNESDAY NIGHT FOR THE TYPICAL COOLER/INTERIOR SPOTS IN NORTHERN LOWER. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING) ISSUED AT 700 PM EDT SUN SEP 27 2015 LOW VFR/HIGH MVFR CIGS WILL HOLD OVER ALL NRN LWR MICHIGAN TAF SITES THRU MONDAY EVENING ALONG THE NORTHWESTERN EDGE OF THE MOISTURE SHIELD ASSOCIATED WITH LOW PRESSURE OFF THE ATLANTIC COAST. LLWS WILL DEVELOP LATE TONIGHT AND CONTINUE INTO EARLY MONDAY. SURFACE WINDS WILL REMAIN FROM THE S/SW AOB 10 KTS THRU THE TAF FORECAST PERIOD. && .MARINE... ISSUED AT 414 PM EDT SUN SEP 27 2015 A WEAK UPPER LEVEL SYSTEM FLOATING AROUND THE MID ATLANTIC WILL CONTINUE MOSTLY CLOUDY SKIES THROUGH TONIGHT. A COLD FRONT WITH STRENGTHENING SW WINDS AHEAD OF IT FOR TONIGHT INTO MONDAY MORNING WILL BRING SOME LOW END ADVISORY LEVEL WINDS WITH SMALL CRAFT ADVISORIES REMAINING POSTED. THE FRONT ARRIVES BY MONDAY EVENING...BRINGING AT LEAST SOME LIGHT RAIN THAT MAY LINGER INTO TUESDAY MORNING. NORTH NORTHWEST WINDS WILL LIKELY BECOME GUSTY TUESDAY WITH ANOTHER ROUND OF SMALL CRAFT ADVISORIES POSSIBLE. && .APX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LH...SMALL CRAFT ADVISORY UNTIL 11 AM EDT MONDAY FOR LHZ347>349. LM...SMALL CRAFT ADVISORY UNTIL 11 AM EDT MONDAY FOR LMZ341-342- 344>346. LS...NONE. && $$ UPDATE...MLR NEAR TERM...SULLIVAN SHORT TERM...JPB LONG TERM...GILLEN AVIATION...MLR MARINE...SULLIVAN
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
730 PM EDT SUN SEP 27 2015 .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 412 PM EDT SUN SEP 27 2015 WATER VAPOR IMAGERY AND RAP ANALYSIS SHOW A MID/UPPER RIDGE EXTENDING FROM THE DESERT SW TO SE CANADA WHILE A TROF IS PROGRESSING THRU WRN CANADA. AT THE SFC...THE TROF IS SUPPORTING A COLD FRONT EXTENDING FROM CNTRL SD ACROSS FAR NW MN TO HUDSON BAY. SW FLOW BTWN THE COLD FRONT AND SFC HIGH PRES CENTERED JUST OFF THE NEW ENGLAND COAST HAS LED TO ANOTHER UNSEASONABLY WARM LATE SEPT DAY TODAY. TEMPS ARE CURRENTLY WELL INTO THE 70S ACROSS MOST OF UPPER MI WITH A FEW LOCATIONS...MAINLY IN THE DOWNSLOPE AREAS NEAR LAKE SUPERIOR...AROUND 80F. FOG/STRATUS THAT WAS OVER CNTRL UPPER MI EARLY THIS MORNING BURNED OFF BY LATE MORNING. STRATOCU THAT WAS OVER IL/SE WI/LAKE MI EARLY TODAY HAS SPREAD N. WHILE STILL S OF KMNM...THE AREA OF MOISTURE HAS LED TO MORE CLOUD COVER FROM AROUND KISQ/KERY EASTWARD. OTHERWISE...SKIES ARE MOSTLY SUNNY. DURING THE SHORT TERM...FOCUS WILL BE ON CLOUD TRENDS THIS EVENING FOR VIEWING LUNAR ECLIPSE AND THEN PCPN POTENTIAL AS WRN CANADA TROF CONTINUES EASTWARD...PUSHING SFC COLD FRONT ACROSS THE AREA MON. WITH COLD FRONT APPROACHING...MODELS SHOW WINDS IN THE APPROACHING CLOUD BEARING LAYER (ROUGHLY 875-850MB) VEERING SOME TONIGHT. THUS...THE DIRECTION OF MOVEMENT OF THE STRATOCU APPROACHING FROM S SHOULD TEND TO TAKE ON MORE OF AN EASTERLY COMPONENT WITH TIME. AT THIS POINT...IT APPEARS LOCATIONS ROUGHLY EAST OF AN IRON MTN TO MUNISING LINE WILL HAVE THE MOST CLOUD COVER...POTENTIALLY OBSCURING MUCH OF THE LUNAR ECLIPSE THIS EVENING AT A FEW LOCATIONS. NAM IN PARTICULAR IS AGGRESSIVE IN MOISTENING LOWER LEVELS BLO STRATOCU LAYER FARTHER TO THE W...BUT DON`T THINK THIS WILL TRANSLATE TO LOW CLOUD DEVELOPMENT THIS EVENING EVEN IF IT IS CORRECT WITH THE MOISTURE. ATTENTION THEN TURNS TO APPROACHING COLD FRONT. THERE ARE ONLY VERY MINOR DIFFERENCES IN THE MODELS IN TIMING FRONT ACROSS THE AREA... REACHING THE W EARLY MON MORNING AND EXITING THE SE LATE AFTN. GUIDANCE SUPPORTS SCT/CHC POPS LATE TONIGHT OVER THE W. BIGGER UNCERTAINTY CONTINUES TO BE WHETHER THE UPPER JET CONFIGURATION WITH RIGHT ENTRANCE UPPER DIVERGENCE AND LOW/MID LEVEL FGEN UNDERNEATH WILL BE SUFFICENT TO HELP DEVELOP A HEAVIER/MORE SOLID BAND OF SHRA JUST BEHIND THE FRONT AS IT MOVES SE ACROSS THE AREA MON. THE MAJORITY OF GUIDANCE SUPPORTS THE IDEA OF IMPROVED FORCING LEADING TO AN INCREASE IN SHRA COVERAGE ACROSS AT LEAST THE SCNTRL AND ERN FCST AREA MON AFTN. WITH THE LAST FEW HRS OF THE LATEST RAP RUN ENDING AT 12Z MON APPEARING TO SUPPORT THAT IDEA AS IT HAS STRONGER FORCING DEVELOPING TO THE W AT THE END OF THE MODEL RUN...WILL RAISE POPS FOR MON...ESPECIALLY SCNTRL AND E WHERE LIKELY/NMRS WILL BE UTILIZED LATE. NOT OUT OF THE QUESTION THAT THERE COULD BE A FEW RUMBLES OF THUNDER...BUT POTENTIAL IS TOO LOW AT THIS POINT TO INCLUDE MENTION. .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 158 PM EDT SUN SEP 27 2015 AN UPPER TROUGH WILL BE BEARING DOWN ON THE AREA MON NIGHT...BUT AN EMBEDDED SHORTWAVE TROUGH WILL BE THE FOCUS FOR SOME SHOWERS THAT MAY GRAZE FAR SERN UPPER MI IN THE FEW FEW HOURS AFTER 00Z TUE. THESE SHOWERS WILL QUICKLY EXIT AS SFC HIGH PRESSURE MOVES IN FROM THE W AND THE UPPER TROUGH AXIS MOVES OVERHEAD ON TUE. 18Z 850MB TEMPS WILL BE NEAR OR BELOW 0C...WHICH WILL MAKE FOR HIGHS IN THE MID 50S TO AROUND 60. NW WINDS GUSTING TO 20-25MPH NEAR LAKE SUPERIOR AND E WILL MAKE THAT FEEL A BIT CHILLIER. WILL INCREASE CLOUD COVER OVER THE E NEAR LAKE SUPERIOR AS LAKE EFFECT CLOUDS SHOULD RESULT...BUT WILL ALSO SHOW CLOUDS DECREASING IN THE AFTERNOON AS HIGH AIR CONTINUES TO INTRUDE. THE SFC HIGH MOVES OVER TUE NIGHT AS 850MB TEMPS REMAIN AROUND 0C. PWATS DROP TO AROUND 0.25 INCHES AND WINDS WILL BE LIGHT...SO RADIATIONAL COOLING AFTER AN ALREADY COOL DAY WILL MAKE FOR VERY COLD LOW TEMPS MAINLY IN THE 20S AND 30S...COLDEST INTERIOR OF COURSE. WILL NOT MAKE SIGNIFICANT CHANGES TO THE GOING FORECAST AS VALUES ARE ON THE LOW END OF GUIDANCE...WHICH LOOKS GOOD. FROST APPEARS LIKELY FOR MUCH OF THE AREA...EVEN SOME SHORELINE AREAS. THE HIGH WILL MOVE E ON WED...AS WILL THE 850MB THERMAL TROUGH...ALLOWING FOR 1-2 DEGREE WARMER MAX TEMPS THAN ON TUE...HIGHS AROUND 60. CONTINUED TO NOTE WHAT THE PREVIOUS SHIFT SAW IN MODEL TRENDS...DRYER WEATHER FOR THE LAST HALF OF THE WEEK. CAN NOT BE TOO CONFIDENT...THOUGH...GIVEN VERY POOR RUN TO RUN CONTINUITY IN THE PATTERN OVER THE LAST FEW MODEL RUNS. WILL CONTINUE TO RELY ON CONSENSUS GUIDANCE...WHICH WILL TREND THE FORECAST DRYER. TEMPS LOOK TO TOP OUT IN THE 60S FOR THE LAST HALF. MIN TEMPS WILL BE TRICKIER GIVEN THE GREATER RELIANCE ON CLOUD COVER...WHICH IS QUITE UNCERTAIN...BUT IT LOOKS LIKE WED NIGHT WILL BE COLDEST WITH LOWS POSSIBLY IN THE MID TO UPPER 30S INLAND AND WARMER NEAR THE SHORE. COULD SEE SOME PATCHY FROST WED NIGHT...BUT WILL HAVE TO GET CLOSER BEFORE ADDING THAT TO THE FORECAST. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING) ISSUED AT 725 PM EDT SUN SEP 27 2015 THRU TONIGHT...VFR CONDITIONS WILL CONTINUE TO BE THE RULE AT KIWD/KCMX/KSAW. GUSTY WINDS WILL DIMINISH THIS EVENING WITH NOCTURNAL COOLING AND THE RESULTANT STABILIZATION WILL RESULT IN LLWS DEVELOPING AT ALL TERMINALS. APPROACHING COLD FRONT WILL THEN MOVE ACROSS THE AREA MON MORNING AND EARLY AFTN...BRINGING THE POTENTIAL OF -SHRA. AROUND THE TIME OF FROPA OR JUST AFTER...EXPECT A PERIOD OF MVFR CIGS. SHOULDN`T LAST MUCH MORE THAN A FEW HRS AT EACH TERMINAL. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 412 PM EDT SUN SEP 27 2015 AHEAD OF AN APPROACHING COLD FRONT...S TO SW WINDS ACROSS LAKE SUPERIOR WILL GUST TO AROUND 25KT TONIGHT...BUT UP TO 30KT AT THE HIGHEST OBS PLATFORMS. THE FRONT WILL CROSS LAKE SUPERIOR LATE TONIGHT AND MON...BRINGING A WIND SHIFT TO THE W TO NW WITH SPEEDS GENERALLY UNDER 20KT. AN UPTICK IN WINDS IS EXPECTED MON NIGHT/TUE TO 20-30KT...ESPECIALLY OVER CNTRL AND EASTERN LAKE SUPERIOR AS INSTABILITY INCREASES WITH INCREASINGLY COLDER AIR FLOWING OVER THE LAKE AHEAD OF APPROACHING HIGH PRES. WINDS WILL THEN DIMINISH TO UNDER 15KT W TO E TUE NIGHT AS HIGH PRES SETTLES OVER THE UPPER LAKES. THE HIGH PRES WILL THEN DRIFT TO THE ENE WED THRU FRI...BUT WILL MAINTAIN RIDGING BACK INTO THE UPPER LAKES. AS A RESULT...WHILE WINDS WILL INCREASE SOME...SPEEDS SHOULD REMAIN MOSTLY 20KT OR LESS DURING THE LAST HALF OF THE WEEK. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...ROLFSON LONG TERM...TITUS AVIATION...VOSS MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
1100 PM CDT SUN SEP 27 2015 .UPDATED FOR 06Z AVIATION DISCUSSION... ISSUED AT 1057 PM CDT SUN SEP 27 2015 && .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 323 PM CDT SUN SEP 27 2015 AS OF 3PM THIS AFTERNOON...THE APPROACHING COLD FRONT WAS JUST NORTHWEST OF ALEXANDRIA. BASED ON LATEST HI-RES GUIDANCE AND CURRENT POSITION...SLIGHTLY SLOWED THE APPROACH OF THE FRONT TONIGHT THROUGH TOMORROW MORNING IN THE GOING FORECAST...BY JUST AN HOUR OR TWO. AS FAR AS CLOUD COVER FOR VIEWING THE ECLIPSE IS CONCERNED...STILL LOOKS LIKE A FEW CLOUDS COULD REACH THE METRO CLOSER TO 11PM-12AM...BUT SKIES SHOULD BE PARTLY CLOUDY FOR VIEWING. THE LATEST HRRR RUN SEEMS TO HAVE A GOOD HANDLE ON THE CLOUD COVER. BASED ON ITS TREND...AREAS FROM REDWOOD FALLS THROUGH ST CLOUD AND WEST OF THERE WILL HAVE TO CONTEND WITH CLOUDY SKIES DURING THE ECLIPSE. SOME OF THE CAMS SHOWED DECENT AGREEMENT IN KEEPING THE MINNESOTA PORTION OF THE FA DRY TONIGHT...WITH THE MOISTURE FINALLY ENOUGH IN WESTERN WI AFTER MIDNIGHT TO SEE SOME SHOWERS DEVELOP...THEN LIGHTING UP THE FRONTAL BOUNDARY TOMORROW AFTERNOON WITH ADDITION SHOWERS...MAINLY FROM WEST CENTRAL WI NEAR EAU CLAIRE...THROUGH SOUTH CENTRAL MN /NEAR ALBERT LEA/. NAM SHOWED BEST LI`S BECOMING NEGATIVE DURING THE AFTERNOON AND MODEL SOUNDINGS INDICATED A SMALL AREA OF CAPE...ENOUGH FOR ADDING A MENTION OF ISOLATED THUNDER TO THE FORECAST FOR TOMORROW. MEANWHILE...A STRONG HIGH WILL BE POISED TO PLUNGE INTO OUR AREA WITH RAPID DRYING AND CLEARING SKIES IN CENTRAL MN BY TOMORROW AFTERNOON. THE DROP IN DEW POINTS WILL LAG A BIT BEHIND THE FRONT...BUT BY LATE TOMORROW AFTERNOON...DEW POINTS WILL BE NEAR 40 NEAR ALEXANDRIA...WITH UPPER 40S DEW POINTS WORKING INTO THE METRO...MAKING IT FEEL MUCH MORE LIKE FALL BY THE END OF THE SHORT TERM PERIOD. .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 323 PM CDT SUN SEP 27 2015 ONE THING THAT HAS NOT CHANGED IN THE EXTENDED IS THE LACK OF RUN-TO- RUN CONSISTENCY WITH ANY OF THE MODELS AS SPLIT FLOW DEVELOPS ACROSS THE CONUS. THE MAIN POLAR JET WILL WEAKEN CONSIDERABLY AS IT RETREATS TO THE NORTH UP ACROSS THE CANADIAN ARCTIC...WITH A WEAK SUBTROPICAL JET SLIDING ACROSS THE CENTRAL/SRN CONUS. THIS WEAKENING OF THE JETS RESULTS IN A WEAKLY FORCED PATTERN IN WHICH THE GUIDANCE IS STRUGGLING TO HANDLE WHERE UPPER HIGHS/LOWS WILL BE CUT-OFF FROM THE FLOW. IN GENERAL THOUGH THE DEFINITE TREND WE HAVE SEEN WITH THE MODELS IS THAT NEXT WEEK WILL BE DRY. THE GFS/ECMWF SHOW A TROUGH DEVELOPING OVER HUDSON BAY INTO QUEBEC AS A CLOSED HIGH DEVELOPS OVER NRN MANITOBA INTO NW ONTARIO. THIS BECOMES THE PERFECT UPPER AIR SETUP FOR DEVELOPING A HUDSON HIGH AT THE SFC...WHICH IS WHAT BOTH MODELS SHOW. THIS WILL KEEP US IN A VERY DRY SE FLOW MUCH OF NEXT WEEK...KEEPING THE PRECIP WEST AND SOUTHWEST THROUGH THE WEEKEND. AS A RESULT...BIGGEST CHANGE TO THE FORECAST FOR TODAY WAS TO START CONSIDERABLY CUTTING BACK POPS FOR THE END OF NEXT WEEK INTO NEXT WEEKEND...THOUGH IF THE 00Z MODELS CONTINUE DOWN THE SAME ROAD...WE COULD PROBABLY CUT THEM EVEN FURTHER WITH THE NEXT UPDATE. FOR THE FRONT DROPPING ACROSS THE AREA TOMORROW...THERE STILL LOOKS TO BE LINGERING PRECIP BEHIND THE FRONT. THE 12Z MODELS THOUGH ARE IN GOOD AGREEMENT WITH MOVING THAT AREA OF PRECIP OUT OF THE AREA PRETTY QUICK MONDAY EVENING...SO WENT PRETTY MUCH DRY WITH THE FORECAST AFTER 3Z TUESDAY. BEHIND THIS FRONT...WE WILL SEE A COOL AND DRY HIGH PRESSURE DROPPING DOWN FROM CANADA. DEWPOINTS WILL BE FALLING BACK INTO AT LEAST THE 30S AND WE WILL LIKELY MIX SOME 20S DOWN TUESDAY AFTERNOON. THIS HIGH WILL LEAD TO OUR COOLEST MORNING OF THE FALL THUS FAR WEDNESDAY MORNING AS WRN WI /CLOSEST TO THE HIGH CENTER/ WILL LIKELY SEE LOWS DROP INTO THE LOW/MID 30S...WITH THE FIRST FREEZE OF THE SEASON LOOKING LIKE A POSSIBILITY OUT AROUND LADYSMITH. FOR THE REST OF THE WEEK...OUR H85 TEMPS LOOK TO HANG OUT BETWEEN +4 AND +8C WHICH TRANSLATES NICELY TO HIGHS IN THE 60S. BEING UNDER THE INFLUENCE OF THE HUDSON HIGH...WE WILL ALSO SEE COOL MORNINGS...WITH LOWS LIKELY DIPPING DOWN INTO THE 30S AND 40S EVERY NIGHT...WITH MORE CHANCES FOR FROST COMING DEPENDING ON WHERE THE RIDGE AXIS SETS UP ON A NIGHTLY BASIS. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 1057 PM CDT SUN SEP 27 2015 VFR CONDITIONS THROUGHOUT...BUT DID ADD SHRA AT A FEW LOCATIONS. MODELS ARE TRENDING A LITTLE HEAVIER ON THE PRECIP...AND IR SATELLITE IMAGERY SHOWS COOLING CLOUD TOPS TO THE WEST...SO THINK A FEW RAIN SHOWERS WILL MOVE THROUGH MONDAY MORNING. KMSP... ADDED VFR SHOWERS FOR THE MORNING PUSH. CLOUD BASES WILL BE ABOVE 3000FT...AND NOT ANTICIPATING AND VISBY RESTRICTIONS. /OUTLOOK FOR KMSP/ TUE...VFR. WIND N AT 5-10KT. WED...VFR. WIND SE AT 5-10KT. THU...VFR. WIND ESE AT 5-10KT. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. && $$ SHORT TERM...SPD LONG TERM...MPG AVIATION...JRB
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
647 PM CDT SUN SEP 27 2015 .UPDATED FOR 00Z AVIATION DISCUSSION... ISSUED AT 639 PM CDT SUN SEP 27 2015 && .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 323 PM CDT SUN SEP 27 2015 AS OF 3PM THIS AFTERNOON...THE APPROACHING COLD FRONT WAS JUST NORTHWEST OF ALEXANDRIA. BASED ON LATEST HI-RES GUIDANCE AND CURRENT POSITION...SLIGHTLY SLOWED THE APPROACH OF THE FRONT TONIGHT THROUGH TOMORROW MORNING IN THE GOING FORECAST...BY JUST AN HOUR OR TWO. AS FAR AS CLOUD COVER FOR VIEWING THE ECLIPSE IS CONCERNED...STILL LOOKS LIKE A FEW CLOUDS COULD REACH THE METRO CLOSER TO 11PM-12AM...BUT SKIES SHOULD BE PARTLY CLOUDY FOR VIEWING. THE LATEST HRRR RUN SEEMS TO HAVE A GOOD HANDLE ON THE CLOUD COVER. BASED ON ITS TREND...AREAS FROM REDWOOD FALLS THROUGH ST CLOUD AND WEST OF THERE WILL HAVE TO CONTEND WITH CLOUDY SKIES DURING THE ECLIPSE. SOME OF THE CAMS SHOWED DECENT AGREEMENT IN KEEPING THE MINNESOTA PORTION OF THE FA DRY TONIGHT...WITH THE MOISTURE FINALLY ENOUGH IN WESTERN WI AFTER MIDNIGHT TO SEE SOME SHOWERS DEVELOP...THEN LIGHTING UP THE FRONTAL BOUNDARY TOMORROW AFTERNOON WITH ADDITION SHOWERS...MAINLY FROM WEST CENTRAL WI NEAR EAU CLAIRE...THROUGH SOUTH CENTRAL MN /NEAR ALBERT LEA/. NAM SHOWED BEST LI`S BECOMING NEGATIVE DURING THE AFTERNOON AND MODEL SOUNDINGS INDICATED A SMALL AREA OF CAPE...ENOUGH FOR ADDING A MENTION OF ISOLATED THUNDER TO THE FORECAST FOR TOMORROW. MEANWHILE...A STRONG HIGH WILL BE POISED TO PLUNGE INTO OUR AREA WITH RAPID DRYING AND CLEARING SKIES IN CENTRAL MN BY TOMORROW AFTERNOON. THE DROP IN DEW POINTS WILL LAG A BIT BEHIND THE FRONT...BUT BY LATE TOMORROW AFTERNOON...DEW POINTS WILL BE NEAR 40 NEAR ALEXANDRIA...WITH UPPER 40S DEW POINTS WORKING INTO THE METRO...MAKING IT FEEL MUCH MORE LIKE FALL BY THE END OF THE SHORT TERM PERIOD. .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 323 PM CDT SUN SEP 27 2015 ONE THING THAT HAS NOT CHANGED IN THE EXTENDED IS THE LACK OF RUN-TO- RUN CONSISTENCY WITH ANY OF THE MODELS AS SPLIT FLOW DEVELOPS ACROSS THE CONUS. THE MAIN POLAR JET WILL WEAKEN CONSIDERABLY AS IT RETREATS TO THE NORTH UP ACROSS THE CANADIAN ARCTIC...WITH A WEAK SUBTROPICAL JET SLIDING ACROSS THE CENTRAL/SRN CONUS. THIS WEAKENING OF THE JETS RESULTS IN A WEAKLY FORCED PATTERN IN WHICH THE GUIDANCE IS STRUGGLING TO HANDLE WHERE UPPER HIGHS/LOWS WILL BE CUT-OFF FROM THE FLOW. IN GENERAL THOUGH THE DEFINITE TREND WE HAVE SEEN WITH THE MODELS IS THAT NEXT WEEK WILL BE DRY. THE GFS/ECMWF SHOW A TROUGH DEVELOPING OVER HUDSON BAY INTO QUEBEC AS A CLOSED HIGH DEVELOPS OVER NRN MANITOBA INTO NW ONTARIO. THIS BECOMES THE PERFECT UPPER AIR SETUP FOR DEVELOPING A HUDSON HIGH AT THE SFC...WHICH IS WHAT BOTH MODELS SHOW. THIS WILL KEEP US IN A VERY DRY SE FLOW MUCH OF NEXT WEEK...KEEPING THE PRECIP WEST AND SOUTHWEST THROUGH THE WEEKEND. AS A RESULT...BIGGEST CHANGE TO THE FORECAST FOR TODAY WAS TO START CONSIDERABLY CUTTING BACK POPS FOR THE END OF NEXT WEEK INTO NEXT WEEKEND...THOUGH IF THE 00Z MODELS CONTINUE DOWN THE SAME ROAD...WE COULD PROBABLY CUT THEM EVEN FURTHER WITH THE NEXT UPDATE. FOR THE FRONT DROPPING ACROSS THE AREA TOMORROW...THERE STILL LOOKS TO BE LINGERING PRECIP BEHIND THE FRONT. THE 12Z MODELS THOUGH ARE IN GOOD AGREEMENT WITH MOVING THAT AREA OF PRECIP OUT OF THE AREA PRETTY QUICK MONDAY EVENING...SO WENT PRETTY MUCH DRY WITH THE FORECAST AFTER 3Z TUESDAY. BEHIND THIS FRONT...WE WILL SEE A COOL AND DRY HIGH PRESSURE DROPPING DOWN FROM CANADA. DEWPOINTS WILL BE FALLING BACK INTO AT LEAST THE 30S AND WE WILL LIKELY MIX SOME 20S DOWN TUESDAY AFTERNOON. THIS HIGH WILL LEAD TO OUR COOLEST MORNING OF THE FALL THUS FAR WEDNESDAY MORNING AS WRN WI /CLOSEST TO THE HIGH CENTER/ WILL LIKELY SEE LOWS DROP INTO THE LOW/MID 30S...WITH THE FIRST FREEZE OF THE SEASON LOOKING LIKE A POSSIBILITY OUT AROUND LADYSMITH. FOR THE REST OF THE WEEK...OUR H85 TEMPS LOOK TO HANG OUT BETWEEN +4 AND +8C WHICH TRANSLATES NICELY TO HIGHS IN THE 60S. BEING UNDER THE INFLUENCE OF THE HUDSON HIGH...WE WILL ALSO SEE COOL MORNINGS...WITH LOWS LIKELY DIPPING DOWN INTO THE 30S AND 40S EVERY NIGHT...WITH MORE CHANCES FOR FROST COMING DEPENDING ON WHERE THE RIDGE AXIS SETS UP ON A NIGHTLY BASIS. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING) ISSUED AT 639 PM CDT SUN SEP 27 2015 VFR CONDITIONS THROUGHOUT. A COLD FRONT WILL SLOWLY PASS THROUGH THE REGION AND BRING MID LEVEL CLOUDS. THERE IS NOT ENOUGH MOISTURE FOR WIDESPREAD PRECIP...SO ONLY MENTIONED VCSH AT THE WISCONSIN SITES. WINDS WILL BE NORTH NORTHEASTERLY BEHIND THE FRONT. KMSP... VFR CONDITIONS THROUGHOUT. HIRES MODELS ARE SLOWER WITH THE WIND SHIFT BEHIND THE FRONT...SO PUSHED BACK THE TIMING IN THE TAF. NOT EXPECTING ANY PRECIPITATION WITH THIS WEAK FRONTAL BOUNDARY. /OUTLOOK FOR KMSP/ TUE...VFR. WIND N AT 5-10KT. WED...VFR. WIND SE AT 5-10KT. THU...VFR. WIND ESE AT 5-10KT. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. && $$ SHORT TERM...SPD LONG TERM...MPG AVIATION...JRB
AREA FORECAST DISCUSSION
NWS DULUTH MN
1239 AM CDT SAT SEP 26 2015 .UPDATE... ISSUED AT 1240 AM CDT SAT SEP 26 2015 UPDATED FOR 06Z TAF DISCUSSION. UPDATE ISSUED AT 918 PM CDT FRI SEP 25 2015 STRATUS/FOG REMAIN SOCKED IN ACROSS MOST OF THE DULUTH CWA AS OF MID EVENING. AFTER SIGNIFICANT EROSION ON THE EDGES LATE THIS AFTERNOON..AS WELL AS FOG/CEILINGS LIFTING SUBSTANTIALLY.. NIGHTTIME IR SAT IMAGERY CLEARLY SHOWS THE WESTERN EDGE OF THE STRATUS EXPANDING TO THE SOUTH AND WEST ONCE AGAIN THE PAST FEW HOURS. WITH LIGHT EAST/SOUTHEAST FLOW PERSISTING..AND THE INVERSION SLOWLY STRENGTHENING OVERNIGHT..WE EXPECT THIS EXPANSION TREND TO CONTINUE OVERNIGHT..WITH STRATUS AND FOG SPREADING BACK ACROSS MOST OF THE REMAINDER OF THE DULUTH CWA WHERE IT ALREADY HAS NOT. WHILE WIDESPREAD DENSE FOG HAS YET TO REFORM AS OF 9 PM ALONG THE NORTH SHORE AND OVER AREAS AT THE SOUTHWEST TIP OF LK SUPERIOR..VISIBILITIES HAVE BEEN SLOWLY LOWERING ALONG THE I35 CORRIDOR FROM MOOSE LAKE TO DULUTH..AND CEILINGS HAVE BEEN GRADUALLY LOWERING. AGAIN..WITH THE WEAK EAST FLOW/UPSLOPE IN VICINITY OF THE NORTH SHORE TERRAIN RIDGE..WE HAVE NO COMPELLING REASON TO PART WITH THE DAYSHIFT-ISSUED DENSE FOG ADVISORY THAT JUST WENT INTO EFFECT. WE STILL EXPECT AT LEAST PATCHY..IF NOT WIDESPREAD DENSE FOG TO REFORM OVER THE NEXT 1-3 HOURS. SOME DRIZZLE IS ALSO POSSIBLE IN THE IMMEDIATE UPSLOPE AREAS FROM DULUTH TO TWO HARBORS AND SILVER BAY. TIGHTENING SOUTHERLY GRADIENT ON SATURDAY SHOULD FINALLY RESULT IN SUFFICIENT FLOW FOR THE LOW LEVEL MOISTURE TO MIX OUT..EVENTUALLY. WE WOULD NOT BE SURPRISED TO SEE LOW CLOUDS/FOG HANG ON INTO THE AFTERNOON IN THE IMMEDIATE VICINITY OF THE NORTH SHORE TERRAIN RIDGE..AS IT WILL BE EARLY-MID AFTERNOON BEFORE FLOW CAN REALLY INCREASE AN BECOME SOUTHERLY IN THESE AREAS PER LATEST CONSENSUS GUIDANCE. && .SHORT TERM...(THIS EVENING THROUGH SATURDAY) ISSUED AT 303 PM CDT FRI SEP 25 2015 WEAK HIGH PRESSURE HAS LED TO A DRY DAY ACROSS THE NORTHLAND...BUT PLENTY OF CLOUDS REMAINED OVER EXTREME NORTHERN WISCONSIN INTO MUCH OF NORTHEAST MINNESOTA. THE FLOW HAS BEEN WEAK AS SEEN WITH KDLH VWP ONLY SHOWING WINDS OF LESS THAN 10 KT AT 925MB/850MB. THERE WILL LIKELY BE SOME ADDITIONAL CLEARING OVER NORTHERN WISCONSIN INTO PARTS OF NORTHERN MINNESOTA...BUT THE RAP SUGGESTS LOWER CLOUDS WILL EXPAND AGAIN OVERNIGHT AS THE INVERSION STRENGTHENS. FOG WILL AGAIN BE POSSIBLE...ESPECIALLY ADJACENT TO LAKE SUPERIOR WHERE AN ONSHORE FLOW WILL CONTINUE. WE ISSUED A DENSE FOG ADVISORY FOR THE NORTH SHORE DOWN INTO THE TWIN PORTS REGION LATER THIS EVENING THROUGH SATURDAY MORNING. FOG MAY BE DENSE ELSEWHERE...ESPECIALLY IN AREAS THAT HAVE CLEARED OUT. LATER SHIFTS MAY NEED TO EXPAND THE ADVISORY. AS THE WEAK HIGH DEPARTS...THE GRADIENT WILL TIGHTEN AS A COLD FRONT/LOW PRESSURE SYSTEM MOVE INTO THE NORTHERN PLAINS. WE EXPECT THE CLOUDS/FOG TO SCOUR OUT MOST AREAS SATURDAY DUE TO STRONGER WINDS AND BETTER MIXING. THE NORTH SHORE WILL BE LAST TO SEE THE CLOUDS/FOG LIFT. SOUTHERLY WINDS WILL KEEP TEMPERATURES IN THE SIXTIES ALONG THE NORTH SHORE...BUT THE REST OF THE NORTHLAND WILL SEE HIGHS FROM 70 TO 76. .LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY) ISSUED AT 303 PM CDT FRI SEP 25 2015 THE FOCUS IN THE LONG TERM IS ON PCPN ASSOCIATED WITH A COLD FRONT EXPECTED TO MOVE THROUGH THE NORTHLAND LATE SUNDAY AND MONDAY. THE LATEST GFS/GEM/ECMWF APPEAR TO BE IN GOOD AGREEMENT WITH THE TIMING OF THE FRONT AND PCPN...AND GENERALLY FASTER THAN THEIR EARLIER RUNS. THEREFORE...WAS CONFIDENT ENOUGH TO SPEED UP THE TIMING OF THE SHOWERS. STILL HAVE LOW CHANCES OF SHOWERS FOR TUESDAY NIGHT INTO THURSDAY...BUT MIGHT BE ABLE TO CUT BACK ON THIS WITH SUBSEQUENT FORECASTS SINCE THE MODELS ARE TRENDING TOWARDS HIGH PRESSURE AND A DRIER FORECAST FOR THIS THE MIDDLE OF THE WEEK. SUNDAY...THERE WILL BE SUNNY SKIES AND WARM SOUTHERLY FLOW ACROSS THE NORTHLAND AS A COLD FRONT IN CANADA APPROACHES THE NW FORECAST AREA. THE GFS BUFR AND NAM12 MODEL SOUNDINGS ARE IN GOOD AGREEMENT...HAVING 25 TO 30 KNOTS OF WIND SPEED IN THE MIXING LAYER IN BOTH MODELS. THEREFORE...CONFIDENT ENOUGH TO INCREASE THE WIND SPEEDS FOR THE AFTERNOON. WIDESPREAD WIND GUSTS OF 20 TO 25 MPH ARE LIKELY...AND MIGHT NEED TO INCREASE THIS TO NEARLY 30 MPH WITH SUBSEQUENT FORECASTS. IT WILL BE THE WARMEST DAY OF THE PERIOD...AND PROBABLY OF NEXT WEEK...WITH HIGHS REACHING THE MIDDLE 70S. LATE SUNDAY INTO MONDAY NIGHT...A COLD FRONT WILL PASS THROUGH THE NORTHLAND...GENERALLY FROM NW TO SE...DURING THIS TIME. THE FRONT WILL BEGIN TO BRING A SUBSTANTIAL DROP IN TEMPERATURE...WHICH WILL NOT BE FULLY REALIZED UNTIL TUESDAY. LIGHT RAIN IS POSSIBLE ALONG AND IN THE WAKE OF THE FRONT...ESPECIALLY ACROSS THE SOUTHERN FORECAST AREA LATE MONDAY AFTERNOON AND INTO MONDAY NIGHT. THE PREVIOUS FORECAST HAD THUNDER...BUT THE GFS AND SREF INDICATE LITTLE IF NO MOST UNSTABLE CAPE...SO FELT COMFORTABLE REMOVING THUNDER FROM THE FORECAST. TUESDAY...HIGH PRESSURE WILL SETTLE OVER THE NORTHLAND...RESULTING IN SUNNY SKIES...BUT TEMPERATURES WILL BE MUCH COOLER THAN JUST A COUPLE DAYS BEFORE. HIGHS WILL LIKELY BE IN THE 50S. THIS LATEST FORECAST HAS MIDDLE 50S OVER THE NORTH TO NEAR 60 OVER THE SOUTH...BUT MIGHT NEED TO LOWER THIS SEVERAL DEGREES. TUESDAY NIGHT...CLEAR SKIES AND VERY LIGHT WINDS WITH THE PASSING HIGH PRESSURE WILL PROMOTE STRONG RADIATIONAL COOLING. THE MODELS ARE TRENDING COLDER...AND MIGHT NEED TO LOWER THE FORECAST MUCH MORE THAN WE CURRENTLY HAVE IN THE FORECAST. NORTHERN MINNESOTA COULD FACE THE THREAT OF FROST. WEDNESDAY AND THURSDAY...THE HIGH PRESSURE WILL SHIFT EAST OF THE NORTHLAND AND LIGHT SOUTHERLY RETURN FLOW WILL DEVELOP ACROSS THE REGION. THIS WILL BRING A SLIGHT WARMING TREND INTO THURSDAY. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 1240 AM CDT SAT SEP 26 2015 LIFR TO IFR CONDITIONS EXPECTED THROUGH THE MORNING HOURS AT MOST TAF SITES...THEN IMPROVING TO VFR BY LATE MORNING. IFR/LIFR FOG/STRATUS HAS DEVELOPED ACROSS NORTHEAST MINNESOTA AND NORTHWEST WISCONSIN THIS EVENING AND WILL PERSIST THROUGH THE MORNING...WITH THE LOWEST VISIBILITIES AT DLH WHERE THE MOIST MARINE LAYER IS RESULTING IN VISIBILITY BELOW A QUARTER MILE. IMPROVEMENT FROM WEST TO EAST MID MORNING TOMORROW...MOST SITES IMPROVE TO VFR BY 14-15Z. DLH MAY REMAIN IFR TO MVFR THROUGH THE LATE MORNING...BUT HAVE CONFIDENCE CONDITIONS IMPROVE TO VFR BY THE AFTERNOON. SATURDAY AFTERNOON AS SKIES CLEAR OUT WINDS WILL PICK UP DUE TO AN INCREASING PRESSURE GRADIENT...SOUTH WINDS GUSTING TO 20-25 KTS AT INL AND 15-20KTS ELSEWHERE IN NORTHEAST MINNESOTA. WINDS BECOME LIGHT BY THE EVENING HOURS...WITH THE POSSIBILITY FOR MVFR CEILINGS AT DLH...AND POSSIBLY SOME FOG DEVELOPING AGAIN. ALSO...LOW LEVEL WIND SHEAR IS EXPECTED AT INL AS A STRONG NOCTURNAL LOW LEVEL JET DEVELOPS DUE TO A COLD FRONT ADVANCING FROM THE NORTHWEST...WINDS UP TO AROUND 45KTS AT 2KFT AGL AFTER 03Z. && .PRELIMINARY POINT TEMPS/POPS... DLH 56 74 56 69 / 0 0 20 20 INL 58 75 50 64 / 0 40 30 0 BRD 59 77 57 70 / 0 0 10 20 HYR 56 76 58 71 / 0 0 10 30 ASX 56 76 58 70 / 0 0 10 30 && .DLH WATCHES/WARNINGS/ADVISORIES... WI...DENSE FOG ADVISORY UNTIL 10 AM CDT THIS MORNING FOR WIZ001. MN...DENSE FOG ADVISORY UNTIL 10 AM CDT THIS MORNING FOR MNZ020-021- 037. LS...NONE. && $$ UPDATE...JJM/MILLER SHORT TERM...MELDE LONG TERM...GROCHOCINSKI AVIATION...JJM
AREA FORECAST DISCUSSION...UPDATED
NWS BILLINGS MT
857 PM MDT SUN SEP 27 2015 .UPDATE... ACTIVITY CONTINUES ACROSS THE FROM MILES CITY TO HARDIN AND OVER TO LIVINGSTON AS SOME FRONTOGENESIS CONTINUES TO PUSH ACROSS THE AREA. MODELS HAVE BEEN SLOW TO PICK UP ON THIS...BUT HAVE NOW BEGUN TO HANDLE IT BETTER. HAVE UP POPS ACROSS SOUTH CENTRAL MONTANA. REIMER && .SHORT TERM...VALID FOR MON AND TUE... HEIGHTS STILL FALLING ACROSS THE AREA AS AN UPPER LEVEL TROUGH MOVES FROM ALBERTA INTO SASKATCHEWAN. HIGH PRESSURE BUILDING INTO NORTHERN MONTANA WITH THIS TROUGH MOVEMENT IS BRINGING EASTERLY LOW LEVEL FLOW AND MUCH COOLER TEMPERATURES. WATER VAPOR SHOWS MOISTURE MOVING OVER THE AREA BUT DEEPER TAP IS OVER WYOMING AND CURRENT RADAR DOES SO ANY PRECIPITATION IS LIMITED TO THE HIGHER TERRAIN OVER THE PARK AND THE BIG HORNS. WITH DEWPOINTS ON THE RISE HRRR CONTINUES TO INDICATE CLOUD COVER WILL INCREASE OVER SOUTHERN MONTANA AND LIGHT SHOWERS DEVELOPING AFTER 9 PM. UNFORTUNATELY THIS TIMING MAY IMPACT LUNAR ECLIPSE VIEWING FOR PEOPLE. MONDAY IS MOSTLY DRY WITH A CONTINUED COOLING TREND WITH HEIGHTS BUILDING WEAKLY OVER THE AREA. MONDAY NIGHT ANOTHER ROUND OF SHOWERS BECOMES POSSIBLE FOR SOUTHERN PORTIONS OF SOUTHEAST MONTANA AS A WEAK SHORTWAVE MOVES THROUGH THE AREA AND MOISTURE IS PULLED INTO THAT AREA AROUND SURFACE HIGH PRESSURE OVER THE EASTERN DAKOTAS. STILL NOT A BUNCH OF MOISTURE EXPECTED. TUESDAY HEIGHTS BUILD UPSTREAM WITH DOWNSLOPE SURFACE FLOW DEVELOPING. THIS WILL BRING A REBOUND IN TEMPERATURES AND DRYING BUT NO WHERE NEAR THE SUMMERTIME CONDITIONS SEEN EARLIER THIS WEEKEND. BORSUM .LONG TERM...VALID FOR WED...THU...FRI...SAT...SUN... EXTENDED DETERMINISTIC MODELS WERE SHOWING AGREEMENT EARLY...WHILE THE EURO ENSEMBLES CONTINUED TO SHOW UNCERTAINTY WITH THE PATTERN THROUGH THE PERIOD...AND THE GEFS SHOWED GOOD AGREEMENT UNTIL 00Z FRI. NOTED THAT DETERMINISTIC MODELS START FALLING OUT OF AGREEMENT ON FRI WITH POTENIALLY POTENT APPROACHING WEST-COAST SYSTEM. UPPER RIDGING SHOULD DOMINATE THROUGH THURSDAY AFTERNOON... TO THEN BE REPLACED BY PACIFIC TROUGH WHEN MODEL QPF BEGINS TO INCREASE WITH ASSOCIATED FORCING IN WESTERN ZONES. THE TROUGH WILL FORM AN UPPER LOW THAT SHIFTS SE DURING FRI... WITH TRENDING RAINFALL ACCUMULATIONS IN THE SAME DIRECTION. ISOLATED TO SCATTERED POPS ARE PRESENT IN THE GRIDS TO COVER THIS CHANCE OF SHOWERS AND THUNDERSTORMS OVER MOST THE AREA ON THURSDAY THROUGH FRIDAY AFTERNOON. CURRENT SOUTHERN EXTENT OF TRACK SHOULD BRING COOLER WEATHER INTO THE AREA GRADUALLY... AS THE FRONTAL COMPLEX AND SFC LOW ALSO REMAINS FURTHER SOUTH. GFS SOLUTION HAS MID-LEVEL TEMPS AND QPF IN FAVOR OF AT LEAST SOME MOUNTAIN SNOWFALL THROUGH SUNDAY AFTERNOON BUT EURO IS SIGNIFICANTLY WARMER AND DRIER IN THE SAME PERIOD. THIS SOLUTION BRINGS AN UPPER LOW ONTO THE CENTRAL CA COST...WHILE THE GFS HAD THE LOW NEARBY BUT MUCH WEAKER..WITH DOWNSTREAM RIDGING IN THE EURO LIKELY THE SOURCE OF WARMER TEMPS. BOTH MODELS THUS HAD VERY DIFFERENT VERSIONS OF FLOW OVER THE REGION BY THE END OF THE PERIOD...WITH SW IN THE EURO AND SOME WEAK CYCLONIC CURVATURE IN THE NW FLOW FROM THE GFS... BUT THE REST OF THE PERIOD WAS DRY IN BOTH MODELS. MROWELL && .AVIATION... ISOLATED TO SCATTERED SHOWERS WILL IMPACT AREAS ALONG AND SOUTH/ EAST OF A KLVM-KBIL-KMLS LINE TONIGHT. VFR SHOULD PREVAIL AT LOWER ELEVATIONS BUT THE BEARTOOTH/ABSAROKA AND BIGHORN MOUNTAINS WILL BE OCCASIONALLY OBSCURED. SHOWERS WILL TAPER OFF FROM WEST TO EAST LATE TONIGHT. IT WILL BE DRY WITH VFR CONDITIONS ACROSS THE AREA ON MONDAY. JKL && .PRELIMINARY POINT TEMP/POPS... MON TUE WED THU FRI SAT SUN ----------------------------------------------------------- BIL 049/068 046/078 051/081 053/072 051/065 047/059 041/063 20/B 00/U 01/U 35/W 53/W 22/W 11/B LVM 041/069 042/078 046/081 048/068 046/064 044/058 039/062 10/U 00/U 01/B 34/W 32/W 22/W 22/W HDN 047/070 044/079 048/084 050/076 048/067 045/062 041/068 20/B 01/B 11/U 35/W 52/W 22/W 11/B MLS 049/068 044/077 048/081 052/077 050/066 046/063 042/066 21/B 01/B 11/U 25/W 43/W 22/W 11/B 4BQ 050/066 046/077 049/082 051/076 049/067 046/064 043/068 21/E 01/B 21/U 13/W 54/W 22/W 21/B BHK 047/064 043/072 047/078 049/073 048/064 044/062 041/064 42/W 01/B 21/U 23/W 44/W 21/B 11/B SHR 046/069 043/079 047/082 048/075 048/067 042/063 039/068 21/B 11/B 11/B 24/W 33/W 22/W 11/B && .BYZ WATCHES/WARNINGS/ADVISORIES... MT...NONE. WY...NONE. && $$ WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION...UPDATED
NWS BILLINGS MT
634 PM MDT SUN SEP 27 2015 .UPDATE... THE ACTIVITY OVER THE BEARTOOTH MOUNTAINS HAVE BEEN A LITTLE MORE ACTIVE THAN THE PREVIOUS FORECAST WOULD SUGGEST. SOME OF THE SHOWERS ARE DRIFTING AS FAR EAST AS YELLOWSTONE COUNTY. HAVE BROUGH A SLIGHT CHANCE INTO SOUTHERN YELLOWSTONE COUNTY AND ADDED A MENTION OF THUNDER OVER THE SOUTHWESTERN ZONES. REIMER && .SHORT TERM...VALID FOR MON AND TUE... HEIGHTS STILL FALLING ACROSS THE AREA AS AN UPPER LEVEL TROUGH MOVES FROM ALBERTA INTO SASKATCHEWAN. HIGH PRESSURE BUILDING INTO NORTHERN MONTANA WITH THIS TROUGH MOVEMENT IS BRINGING EASTERLY LOW LEVEL FLOW AND MUCH COOLER TEMPERATURES. WATER VAPOR SHOWS MOISTURE MOVING OVER THE AREA BUT DEEPER TAP IS OVER WYOMING AND CURRENT RADAR DOES SO ANY PRECIPITATION IS LIMITED TO THE HIGHER TERRAIN OVER THE PARK AND THE BIG HORNS. WITH DEWPOINTS ON THE RISE HRRR CONTINUES TO INDICATE CLOUD COVER WILL INCREASE OVER SOUTHERN MONTANA AND LIGHT SHOWERS DEVELOPING AFTER 9 PM. UNFORTUNATELY THIS TIMING MAY IMPACT LUNAR ECLIPSE VIEWING FOR PEOPLE. MONDAY IS MOSTLY DRY WITH A CONTINUED COOLING TREND WITH HEIGHTS BUILDING WEAKLY OVER THE AREA. MONDAY NIGHT ANOTHER ROUND OF SHOWERS BECOMES POSSIBLE FOR SOUTHERN PORTIONS OF SOUTHEAST MONTANA AS A WEAK SHORTWAVE MOVES THROUGH THE AREA AND MOISTURE IS PULLED INTO THAT AREA AROUND SURFACE HIGH PRESSURE OVER THE EASTERN DAKOTAS. STILL NOT A BUNCH OF MOISTURE EXPECTED. TUESDAY HEIGHTS BUILD UPSTREAM WITH DOWNSLOPE SURFACE FLOW DEVELOPING. THIS WILL BRING A REBOUND IN TEMPERATURES AND DRYING BUT NO WHERE NEAR THE SUMMERTIME CONDITIONS SEEN EARLIER THIS WEEKEND. BORSUM .LONG TERM...VALID FOR WED...THU...FRI...SAT...SUN... EXTENDED DETERMINISTIC MODELS WERE SHOWING AGREEMENT EARLY...WHILE THE EURO ENSEMBLES CONTINUED TO SHOW UNCERTAINTY WITH THE PATTERN THROUGH THE PERIOD...AND THE GEFS SHOWED GOOD AGREEMENT UNTIL 00Z FRI. NOTED THAT DETERMINISTIC MODELS START FALLING OUT OF AGREEMENT ON FRI WITH POTENIALLY POTENT APPROACHING WEST-COAST SYSTEM. UPPER RIDGING SHOULD DOMINATE THROUGH THURSDAY AFTERNOON... TO THEN BE REPLACED BY PACIFIC TROUGH WHEN MODEL QPF BEGINS TO INCREASE WITH ASSOCIATED FORCING IN WESTERN ZONES. THE TROUGH WILL FORM AN UPPER LOW THAT SHIFTS SE DURING FRI... WITH TRENDING RAINFALL ACCUMULATIONS IN THE SAME DIRECTION. ISOLATED TO SCATTERED POPS ARE PRESENT IN THE GRIDS TO COVER THIS CHANCE OF SHOWERS AND THUNDERSTORMS OVER MOST THE AREA ON THURSDAY THROUGH FRIDAY AFTERNOON. CURRENT SOUTHERN EXTENT OF TRACK SHOULD BRING COOLER WEATHER INTO THE AREA GRADUALLY... AS THE FRONTAL COMPLEX AND SFC LOW ALSO REMAINS FURTHER SOUTH. GFS SOLUTION HAS MID-LEVEL TEMPS AND QPF IN FAVOR OF AT LEAST SOME MOUNTAIN SNOWFALL THROUGH SUNDAY AFTERNOON BUT EURO IS SIGNIFICANTLY WARMER AND DRIER IN THE SAME PERIOD. THIS SOLUTION BRINGS AN UPPER LOW ONTO THE CENTRAL CA COST...WHILE THE GFS HAD THE LOW NEARBY BUT MUCH WEAKER..WITH DOWNSTREAM RIDGING IN THE EURO LIKELY THE SOURCE OF WARMER TEMPS. BOTH MODELS THUS HAD VERY DIFFERENT VERSIONS OF FLOW OVER THE REGION BY THE END OF THE PERIOD...WITH SW IN THE EURO AND SOME WEAK CYCLONIC CURVATURE IN THE NW FLOW FROM THE GFS... BUT THE REST OF THE PERIOD WAS DRY IN BOTH MODELS. MROWELL && .AVIATION... ISOLATED TO SCATTERED SHOWERS WILL IMPACT AREAS ALONG AND SOUTH/ EAST OF A KLVM-KBIL-KMLS LINE TONIGHT. VFR SHOULD PREVAIL AT LOWER ELEVATIONS BUT THE BEARTOOTH/ABSAROKA AND BIGHORN MOUNTAINS WILL BE OCCASIONALLY OBSCURED. SHOWERS WILL TAPER OFF FROM WEST TO EAST LATE TONIGHT. IT WILL BE DRY WITH VFR CONDITIONS ACROSS THE AREA ON MONDAY. JKL && .PRELIMINARY POINT TEMP/POPS... MON TUE WED THU FRI SAT SUN ----------------------------------------------------------- BIL 049/068 046/078 051/081 053/072 051/065 047/059 041/063 20/B 00/U 01/U 35/W 53/W 22/W 11/B LVM 041/069 042/078 046/081 048/068 046/064 044/058 039/062 10/U 00/U 01/B 34/W 32/W 22/W 22/W HDN 047/070 044/079 048/084 050/076 048/067 045/062 041/068 10/B 01/B 11/U 35/W 52/W 22/W 11/B MLS 049/068 044/077 048/081 052/077 050/066 046/063 042/066 21/B 01/B 11/U 25/W 43/W 22/W 11/B 4BQ 050/066 046/077 049/082 051/076 049/067 046/064 043/068 21/E 01/B 21/U 13/W 54/W 22/W 21/B BHK 047/064 043/072 047/078 049/073 048/064 044/062 041/064 42/W 01/B 21/U 23/W 44/W 21/B 11/B SHR 046/069 043/079 047/082 048/075 048/067 042/063 039/068 21/B 11/B 11/B 24/W 33/W 22/W 11/B && .BYZ WATCHES/WARNINGS/ADVISORIES... MT...NONE. WY...NONE. && $$ WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION...UPDATED
NWS BILLINGS MT
356 PM MDT SAT SEP 26 2015 .SHORT TERM...VALID FOR TDY AND SUN... COLD FRONT MOVING THROUGH LEWISTOWN ON TRACK FOR AN EVENING PASSAGE THROUGH SOUTHERN MONTANA AND NORTH CENTRAL WYOMING. RADAR SHOWS SOME WEAK RETURNS WITH HRRR CONTINUING TO ADVERTISE A LITTLE BIT OF DEVELOPMENT ALONG THE FRONTAL BOUNDARY MAINLY NORTH OF THE YELLOWSTONE RIVER SO KEPT AN ISOLATED MENTION BUT DO NOT EXPECT MUCH IN THE WAY OF MOISTURE. DO EXPECT A PERIOD OF 15 TO 20 MPH NORTHERLY WINDS BEHIND THE FRONT ESPECIALLY AS IT HEADS SOUTH OF BILLINGS TOWARDS SHERIDAN. COOLER DAY ON SUNDAY BUT MAINLY DRY UNTIL A WEAK DISTURBANCE APPROACHES LATE IN THE DAY. COULD SEE A FEW MOUNTAIN SHOWERS BUT EXPECT SLIGHTLY BETTER CHANCE FOR SHOWERS OVER SOUTHEAST MONTANA WHERE EASTERLY SURFACE FLOW DEVELOPS AROUND THE LEADING EDGE OF HIGH PRESSURE BEHIND THE FRONT GENERATING A BIT OF UPSLOPE. AGAIN MUCH PRECIPITATION IS NOT EXPECTED BUT CHANCES INCREASE AS THE EVENING PROGRESSES AS MOISTURE DEEPENS AS THE NIGHT GOES ON. CONTINUED COOLING TREND ON MONDAY AS THE EASTERLIES SPREAD WESTWARD AND A BIT OF MIDLEVEL WARMING PROVIDES WEAK LIFT. NOT ENOUGH TO GENERATE MOISTURE FOR THE CENTRAL AND WESTERN ZONES BUT SOUTHEAST MONTANA STILL HAS A CHANCE FOR A SHOWER. BORSUM .LONG TERM...VALID FOR MON...TUE...WED...THU...FRI... LONG TERM PERIOD WILL BEGIN WITH ABOVE NORMAL TEMPERATURES THROUGH WEDNESDAY AFTERNOON BEFORE ANOTHER WEAK DISTURBANCE MOVES IN AND HOPEFULLY RETURNS OUR FORECAST AREA TO SEASONABLE AND COOLER TEMPERATURES. THERE IS MUCH UNCERTAINTY IN THE FORECAST BEYOND FRIDAY WITH A VARIETY OF SOLUTIONS. LONG TERM PERIOD BEGINS WITH A RIDGE AXIS THROUGH THE CENTRAL PARTS OF THE STATES. WARM 850MB TEMPS WILL ALLOW CONDITIONS TO WARM UP VERY WELL WITH UPPER 70S TO LOW 80S EXPECTED ON TUESDAY AND WEDNESDAY AFTERNOONS. CONDITIONS WILL BE MOSTLY DRY ON TUESDAY BUT AS UPPER LEVEL MOISTURE MOVES IN WEDNESDAY AFTERNOON WE COULD SEE SOME SHOWERS AND ISOLATED THUNDERSTORMS WEST OF MILES CITY. NOT WIDESPREAD SHOWERS WITH THIS UPPER LEVEL DISTURBANCE UNTIL THURSDAY. TEMPERATURES BEGIN TO COOL OFF THURSDAY AS THE UPPER LEVEL DISTURBANCE PASSES OVERHEAD. SOME UNCERTAINTY REMAINS IN RAIN AMOUNTS...BUT FOR THE MOST PART THURSDAY APPEARS TO BE A MUCH COOLER AND CLOUDIER DAY AS GOOD FORCING FOR SHOWERS AND ISOLATED THUNDERSTORMS MOVES IN THROUGH THE DAY. IN ADDITION...LEE-SIDE CYCLOGENESIS SHOULD ALLOW ADDITIONAL WRAP AROUND MOISTURE TO PRODUCE SOME HIGHER RAIN AMOUNTS IN EXTREME EASTERN PORTIONS OF THE FORECAST AREA. THE GFS REMAINS THE MOST PROGRESSIVE WHILE THE EURO IS A LITTLE SLOWER MOVING THE SYSTEM OUT SO KEPT SLIGHT CHANCES OF RAIN IN THE FORECAST FRIDAY MORNING BEFORE THE DISTURBANCE MOVES OUT. TEMPERATURES AROUND 70 CAN BE EXPECTED. BEGINNING ON SATURDAY MUCH UNCERTAINTY MOVES INTO THE FORECAST. THE GLOBAL MODELS ARE HAVING TROUBLE HANDLING THE INTERACTION OF A PACIFIC UPPER LEVEL LOW WITH ANOTHER AMPLIFYING SYSTEM LATE IN THE WEEK. THE LATEST GFS ENSEMBLES SHOW MUCH COOLER CONDITIONS WHILE THE 12Z DETERMINISTIC RUN WANTED TO BUILD ANOTHER RIDGE. GIVEN THAT THIS WAS A PRETTY SIGNIFICANT SHIFT FROM THE LAST FEW RUNS LEANED MORE TOWARDS THE ENSEMBLE SOLUTION WHICH WOULD KEEP OUR AREA NEAR OR JUST BELOW SEASONABLE TEMPERATURES FOR SATURDAY. ONE SHOULD NOTE THIS FORECAST IS HIGHLY UNCERTAIN SO SHIFTS IN THE CURRENT FORECAST ARE LIKELY. DOBBS && .AVIATION... VFR CONDITIONS WILL PREVAIL ACROSS THE AREA TONIGHT. THERE WILL CONTINUE TO BE A SLIGHT CHANCE OF SHOWERS AND ISOLATED THUNDERSTORMS OVER THE WESTERN MOUNTAINS THIS AFTERNOON. LOCALIZED OBSCURATIONS ARE POSSIBLE IN ANY SHOWERS. A COLD FRONT WILL PUSH SE THROUGH THE AREA TONIGHT SHIFTING SURFACE WINDS TO THE NW. LOW-LEVEL WIND SHEAR IS POSSIBLE OVER KMLS AT 06Z TONIGHT AND COULD LAST UNTIL ABOUT 13Z TOMORROW. DOBBS && .PRELIMINARY POINT TEMP/POPS... TDY SUN MON TUE WED THU FRI ------------------------------------------------------- BIL 093 055/072 048/070 046/076 053/079 052/073 048/070 0/B 11/B 11/B 11/B 12/W 33/W 32/W LVM 086 047/073 042/071 043/075 046/077 046/069 043/070 1/B 21/B 11/B 11/U 12/W 33/W 21/B HDN 097 052/074 046/072 045/077 049/082 049/076 045/071 0/B 11/B 21/B 11/B 12/W 34/W 42/W MLS 095 057/074 047/069 045/077 050/082 051/075 048/070 0/B 01/B 22/W 11/B 12/W 34/W 43/T 4BQ 096 056/076 049/071 047/077 050/082 052/076 048/071 0/U 00/B 22/T 22/W 21/B 34/W 43/T BHK 091 054/073 047/066 044/071 048/079 050/073 047/067 0/U 00/B 32/T 21/B 21/B 34/W 43/T SHR 094 052/076 046/073 045/076 046/080 049/074 044/070 0/U 00/B 22/T 21/B 22/W 23/W 32/W && .BYZ WATCHES/WARNINGS/ADVISORIES... MT...NONE. WY...NONE. && $$ WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS BILLINGS MT
319 PM MDT SAT SEP 26 2015 .SHORT TERM...VALID FOR SUN AND MON... COLD FRONT MOVING THROUGH LEWISTOWN ON TRACK FOR AN EVENING PASSAGE THROUGH SOUTHERN MONTANA AND NORTH CENTRAL WYOMING. RADAR SHOWS SOME WEAK RETURNS WITH HRRR CONTINUING TO ADVERTISE A LITTLE BIT OF DEVELOPMENT ALONG THE FRONTAL BOUNDARY MAINLY NORTH OF THE YELLOWSTONE RIVER SO KEPT AN ISOLATED MENTION BUT DO NOT EXPECT MUCH IN THE WAY OF MOISTURE. DO EXPECT A PERIOD OF 15 TO 20 MPH NORTHERLY WINDS BEHIND THE FRONT ESPECIALLY AS IT HEADS SOUTH OF BILLINGS TOWARDS SHERIDAN. COOLER DAY ON SUNDAY BUT MAINLY DRY UNTIL A WEAK DISTURBANCE APPROACHES LATE IN THE DAY. COULD SEE A FEW MOUNTAIN SHOWERS BUT EXPECT SLIGHTLY BETTER CHANCE FOR SHOWERS OVER SOUTHEAST MONTANA WHERE EASTERLY SURFACE FLOW DEVELOPS AROUND THE LEADING EDGE OF HIGH PRESSURE BEHIND THE FRONT GENERATING A BIT OF UPSLOPE. AGAIN MUCH PRECIPITATION IS NOT EXPECTED BUT CHANCES INCREASE AS THE EVENING PROGRESSES AS MOISTURE DEEPENS AS THE NIGHT GOES ON. CONTINUED COOLING TREND ON MONDAY AS THE EASTERLIES SPREAD WESTWARD AND A BIT OF MIDLEVEL WARMING PROVIDES WEAK LIFT. NOT ENOUGH TO GENERATE MOISTURE FOR THE CENTRAL AND WESTERN ZONES BUT SOUTHEAST MONTANA STILL HAS A CHANCE FOR A SHOWER. BORSUM .LONG TERM...VALID FOR TUE...WED...THU...FRI...SAT... LONG TERM PERIOD WILL BEGIN WITH ABOVE NORMAL TEMPERATURES THROUGH WEDNESDAY AFTERNOON BEFORE ANOTHER WEAK DISTURBANCE MOVES IN AND HOPEFULLY RETURNS OUR FORECAST AREA TO SEASONABLE AND COOLER TEMPERATURES. THERE IS MUCH UNCERTAINTY IN THE FORECAST BEYOND FRIDAY WITH A VARIETY OF SOLUTIONS. LONG TERM PERIOD BEGINS WITH A RIDGE AXIS THROUGH THE CENTRAL PARTS OF THE STATES. WARM 850MB TEMPS WILL ALLOW CONDITIONS TO WARM UP VERY WELL WITH UPPER 70S TO LOW 80S EXPECTED ON TUESDAY AND WEDNESDAY AFTERNOONS. CONDITIONS WILL BE MOSTLY DRY ON TUESDAY BUT AS UPPER LEVEL MOISTURE MOVES IN WEDNESDAY AFTERNOON WE COULD SEE SOME SHOWERS AND ISOLATED THUNDERSTORMS WEST OF MILES CITY. NOT WIDESPREAD SHOWERS WITH THIS UPPER LEVEL DISTURBANCE UNTIL THURSDAY. TEMPERATURES BEGIN TO COOL OFF THURSDAY AS THE UPPER LEVEL DISTURBANCE PASSES OVERHEAD. SOME UNCERTAINTY REMAINS IN RAIN AMOUNTS...BUT FOR THE MOST PART THURSDAY APPEARS TO BE A MUCH COOLER AND CLOUDIER DAY AS GOOD FORCING FOR SHOWERS AND ISOLATED THUNDERSTORMS MOVES IN THROUGH THE DAY. IN ADDITION...LEE-SIDE CYCLOGENESIS SHOULD ALLOW ADDITIONAL WRAP AROUND MOISTURE TO PRODUCE SOME HIGHER RAIN AMOUNTS IN EXTREME EASTERN PORTIONS OF THE FORECAST AREA. THE GFS REMAINS THE MOST PROGRESSIVE WHILE THE EURO IS A LITTLE SLOWER MOVING THE SYSTEM OUT SO KEPT SLIGHT CHANCES OF RAIN IN THE FORECAST FRIDAY MORNING BEFORE THE DISTURBANCE MOVES OUT. TEMPERATURES AROUND 70 CAN BE EXPECTED. BEGINNING ON SATURDAY MUCH UNCERTAINTY MOVES INTO THE FORECAST. THE GLOBAL MODELS ARE HAVING TROUBLE HANDLING THE INTERACTION OF A PACIFIC UPPER LEVEL LOW WITH ANOTHER AMPLIFYING SYSTEM LATE IN THE WEEK. THE LATEST GFS ENSEMBLES SHOW MUCH COOLER CONDITIONS WHILE THE 12Z DETERMINISTIC RUN WANTED TO BUILD ANOTHER RIDGE. GIVEN THAT THIS WAS A PRETTY SIGNIFICANT SHIFT FROM THE LAST FEW RUNS LEANED MORE TOWARDS THE ENSEMBLE SOLUTION WHICH WOULD KEEP OUR AREA NEAR OR JUST BELOW SEASONABLE TEMPERATURES FOR SATURDAY. ONE SHOULD NOTE THIS FORECAST IS HIGHLY UNCERTAIN SO SHIFTS IN THE CURRENT FORECAST ARE LIKELY. DOBBS && .AVIATION... VFR CONDITIONS WILL PREVAIL ACROSS THE AREA TONIGHT. THERE WILL CONTINUE TO BE A SLIGHT CHANCE OF SHOWERS AND ISOLATED THUNDERSTORMS OVER THE WESTERN MOUNTAINS THIS AFTERNOON. LOCALIZED OBSCURATIONS ARE POSSIBLE IN ANY SHOWERS. A COLD FRONT WILL PUSH SE THROUGH THE AREA TONIGHT SHIFTING SURFACE WINDS TO THE NW. LOW-LEVEL WIND SHEAR IS POSSIBLE OVER KMLS AND KSHR AFTER 06Z TONIGHT AND WILL LAST UNTIL ABOUT 13Z TOMORROW. DOBBS && .PRELIMINARY POINT TEMP/POPS... SUN MON TUE WED THU FRI SAT ----------------------------------------------------------- BIL 055/072 048/070 046/076 053/079 052/073 048/070 047/063 11/B 11/B 11/B 12/W 33/W 32/W 11/B LVM 047/073 042/071 043/075 046/077 046/069 043/070 042/065 21/B 11/B 11/U 12/W 33/W 21/B 22/W HDN 052/074 046/072 045/077 049/082 049/076 045/071 044/067 11/B 21/B 11/B 12/W 34/W 42/W 11/B MLS 057/074 047/069 045/077 050/082 051/075 048/070 045/065 01/B 22/W 11/B 12/W 34/W 43/T 12/W 4BQ 056/076 049/071 047/077 050/082 052/076 048/071 046/067 00/B 22/T 22/W 21/B 34/W 43/T 12/W BHK 054/073 047/066 044/071 048/079 050/073 047/067 045/063 00/B 32/T 21/B 21/B 34/W 43/T 12/W SHR 052/076 046/073 045/076 046/080 049/074 044/070 040/066 00/B 22/T 21/B 22/W 23/W 32/W 22/W && .BYZ WATCHES/WARNINGS/ADVISORIES... MT...NONE. WY...NONE. && $$ WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS HASTINGS NE
225 PM CDT SAT SEP 26 2015 .UPDATE... ISSUED AT 1102 AM CDT SAT SEP 26 2015 ANOTHER UPDATE HAS POSTED. STRATUS CONTS TO LINGER W OF HWY 183. SKY FCST HAS BEEN TRENDED MORE PESSIMISTIC IN THIS AREA...BUT EXPECT GRADUAL IMPROVEMENT AS BREAKS IN THE OVERCAST INCREASE WITH THE STRATUS LIFTING INTO A DECK OF STRATOCU. HIGH TEMPS WERE LOWERED 3-5F W OF HWY 183 WHERE CLOUDS WILL LIMIT HEATING. FOR THE REST OF THE FCST AREA...A VERY NICE DAY IS IN PROGRESS. ENJOY IT! WE WILL BE EVALUATING POTENTIAL FOR FOG REDEVELOPMENT OVER THE W HALF OF THE FCST AREA. TOP/OAX 12Z SOUNDINGS SHOW LOW-LVL DRIER AIR ADVECTING IN FROM THE E. SO IT MIGHT NOT BE A PROBLEM. UPDATE ISSUED AT 728 AM CDT SAT SEP 26 2015 SENT A QUICK UPDATE TO TEMPS/DWPTS/WINDS THRU NOON. OBSERVED TEMPS/DWPTS WERE SVRL DEGS BELOW THE FCST OVER THE NE 1/2 OF THE FCST AREA WHERE SKIES WERE M/CLEAR AND WERE ABOVE THE FCST OVER THE SW 1/2 DUE TO CLOUD COVER. FCST NOW BETTER REFLECTS REALITY. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 345 AM CDT SAT SEP 26 2015 SATELLITE AND OBSERVATIONS SHOW STRATUS ACROSS THE WESTERN TWO THIRDS OF THE FORECAST AREA EARLY THIS MORNING. SO FAR THERE HAVE BEEN A FEW LOCATIONS THAT TEMPORARILY DROP TO LESS THAN A MILE VISIBILITY...BUT THESE SEEM TO BE SHORT LIVED AND AT LEAST SOMEWHAT SPORADIC. THE FIRST CONCERN FOR THE MORNING WILL BE THE FOG. HAVE SOME CONCERN NEAR THE EASTERN EDGE OF THE STRATUS DECK THAT FOG COULD FORM. THE DEW POINT SPREAD IS ONLY A COUPLE OF DEGREES...THE CLEARING SHOULD ALLOW TEMPERATURES TO FALL OFF AND WINDS ARE LIGHT FROM THE EAST. ON THE OTHER HAND...TO THE EAST OF THE STRATUS DECK HAS LOWER DEW POINTS AND A GREATER DEW POINT SPREAD. WINDS ARE STILL LIGHT AND GENERALLY FROM THE EAST. THE LATEST HRRR HAS A SMALL AREA OF LOWER VISIBILITIES A COUPLE HOURS AROUND SUN RISE. THIS AREA IS NEAR THE PROJECTED EDGE OF THE STRATUS AROUND 12Z. WILL CONTINUE TO KEEP THE AREAS OF FOG IN. VISIBILITIES COULD BE AROUND A MILE OR SO AND WILL KEEP IT FOR THE ENTIRE AREA INSTEAD OF GETTING TOO SPECIFIC. THE SHOWERS ACROSS NORTH CENTRAL KANSAS AND FAR SOUTHERN NEBRASKA HAVE ENDED. THERE MAY BE A SPRINKLE OR SO IN A FEW AREAS...BUT DO NOT EXPECT THERE TO BE MUCH OF ANYTHING. WILL REMOVE THE SHOWER CHANCES. A WEAKENING UPPER LEVEL WAVE HAS BEEN DRIFTING TO THE SOUTH OVERNIGHT AND WILL CONTINUE TO MOVE OUT OF THE AREA TODAY. A SURFACE HIGH TO THE EAST WILL CONTINUE TO MOVE TO THE EAST. THE PRESSURE GRADIENT WILL TIGHTEN A LITTLE TODAY AND WINDS WILL TURN TO THE SOUTH AND INCREASE DURING THE DAY. THEY WILL STILL BE FAIRLY LIGHT MAINLY 5 TO 15 MPH. THE MOISTURE WILL DIMINISH AND THE CLOUDS OUT THERE NOW WILL GRADUALLY DIMINISH AND LEAVE MOSTLY SUNNY SKIES. TEMPERATURES THIS AFTERNOON SHOULD BE A LITTLE WARMER THAN YESTERDAY WITH THE SUNSHINE. SKIES WILL REMAIN MOSTLY CLEAR THROUGH THE NIGHT. WINDS WILL BE LIGHT AND DEW POINTS WILL BE LOWER. TEMPERATURES WILL BE A LITTLE COOLER TONIGHT...BUT STILL ABOVE NORMAL FOR THIS TIME OF YEAR. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 401 AM CDT SAT SEP 26 2015 PRIMARY FORECAST CONCERN LIES WITH PRECIPITATION CHANCES. STILL LOOKING AT A DRY END TO THE WEEKEND...WITH MODELS REMAINING IN GOOD AGREEMENT ON SUNDAY...SHOWING THE MAIN UPPER LEVEL RIDGE AXIS CONTINUING TO BE THE MAIN PLAYER ACROSS THE REGION. THIS RIDGE AXIS...SET UP BETWEEN LOW PRESSURE OVER TX AND SHORTWAVE ENERGY MOVING THROUGH THE PAC NW/NRN ROCKIES...EXTENDS FROM HIGH PRESSURE LOCATED OVER THE BAJA THROUGH THE CENTRAL PLAINS. AT THE SFC...EXPECTING SOUTHERLY WINDS TO BE IN PLACE DURING THE DAY...AS THE CWA SITS AHEAD OF AN APPROACHING FRONTAL BOUNDARY. SPEEDS LOOK TO BE ON THE BREEZY SIDE DURING THE AFTERNOON...WITH SPEEDS IN THE 15 TO 20 MPH RANGE. WITH SOME WARMER AIR ALOFT WORKING ITS WAY BACK EAST INTO THE AREA...EXPECTING A BUMP UP IN HIGHS...INTO THE LOWER/MID 80S. STARTING SUNDAY NIGHT AND CONTINUING INTO THE FIRST FEW DAYS OF THE WORK WEEK...UPPER LEVEL ENERGY ASSOCIATED WITH A LOW PRESSURE SYSTEM SLIDING EAST INTO THE HUDSON BAY AREA FURTHER BREAKS DOWN THE MAIN RIDGE AXIS AND STARTS PUSHING IT FURTHER SOUTH. GENERAL AGREEMENT AMONG MODELS SHOW IT LOCATED OVER FAR SRN PORTIONS OF THE CWA/IF NOT JUST SOUTH OF OUR SRN BORDER BY 12Z TUESDAY...WITH MORE ZONAL UPPER LEVEL FLOW IN PLACE BY THEN. THIS SYSTEM WILL ALSO BE PUSHING THAT ABOVE MENTIONED SFC FRONT SOUTH...WITH MODELS NOT IN TOO BAD OF AGREEMENT SHOWING IT BY 12Z MONDAY HAVING MOVED THROUGH A GOOD CHUNK OF OUR SC NEB COUNTIES...AND BY 12Z TUESDAY IS IN THE I-70 AREA OF NRN KS. INCREASED LIFT WITH THIS DISTURBANCE MOVING THROUGH...ALONG WITH MODELS SHOWING MORE FAVORABLE POSITIONING OF UPPER LEVEL JET ENERGY MOVING INTO THE REGION...LOOKS TO BRING PRECIPITATION CHANCES TO THE CWA THROUGH ROUGHLY THE FIRST HALF OF THE WORK WEEK. KEPT THE MAIN AREA OF POPS ACROSS OUR SC NEB COUNTIES...WITH MODELS NOT SHOWING A WHOLE LOT MOVING THROUGH NC KS. HAVE A THUNDER MENTION IN PLACE...WHILE MODELS ARE CERTAINLY NOT SHOWING AN ABUNDANCE OF INSTABILITY...ITS NOT ZERO EITHER. HIGH TEMPERATURES ON MONDAY ARE A BIT TRICKY WITH THAT SFC BOUNDARY CONTINUING TO MOVE SOUTH THROUGH THE DAY...AS WELL AS ON TUESDAY WITH THE POTENTIAL FOR INCREASED CLOUD COVER/PRECIP AFFECTING A GOOD CHUNK OF THE CWA. MODELS SHOWING WARMER TEMPS ALOFT ARE SLOW TO MOVE OUT OF ESP SRN PORTIONS OF THE CWA ON MONDAY...AND HAVE TEMPS RANGING FROM THE MID/UPPER 70S IN THE NORTH TO UPPER 80S SOUTH. TUESDAY LOOKS TO BE COOLER WITH HIGHS IN THE UPPER 60S NORTH TO UPPER 70S SOUTH. HAVE SOME LINGERING 20 POPS IN PLACE ON WED ACROSS NERN PORTIONS OF THE CWA...BUT CONFIDENCE IN WHETHER THEY NEED TO BE THERE AT ALL OR NOT IS NOT HIGH. MODELS ARE SHOWING THAT UPPER LEVEL RIDGING IS STARTING TO BUILD BACK NORTH ACROSS THE ROCKIES/HIGH PLAINS DURING THE DAY...AS HIGH PRESSURE MOVES INTO THE NM/MEX BORDER AREA. THIS RIDGING SLIDES EAST ONTO THE PLAINS AS WE GET INTO THURSDAY...BEING PUSHED BY ANOTHER UPPER LEVEL DISTURBANCE DIGGING SOUTH INTO THE ROCKIES. EXPECTING ANOTHER BUMP BACK UP IN TEMPS...INTO THE UPPER 70S TO MID 80S BY THURSDAY. LOOKING TO THE VERY END OF THIS FORECAST PERIOD THURS NIGHT/FRI...THIS SYSTEM WILL BE LOOKING TO BRING THE NEXT CHANCE FOR PRECIPITATION TO THE REGION...BUT TIMING/LOCATION DETAILS HAVE SOME DETAILS TO BE WORKED OUT IN THE COMING DAYS. && .AVIATION...(FOR THE 21Z KGRI/KEAR TAFS THROUGH 21Z SUN AFTERNOON) ISSUED AT 224 PM CDT SAT SEP 26 2015 THIS AFTERNOON: VFR WITH JUST A FEW STRATOCU AROUND 4K FT. SE WINDS 8-12 KTS. CONFIDENCE: HIGH TONIGHT: VFR SKC. SE WINDS UNDER 10 KTS BECOME S. CONFIDENCE: HIGH SUN THRU 18Z: VFR SKC. SSW WINDS INCREASE AND GUST UP TO 25 KTS AFTER 15Z. CONFIDENCE: HIGH && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$ UPDATE...HALBLAUB SHORT TERM...JCB LONG TERM...ADP AVIATION...HALBLAUB
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1102 AM CDT SAT SEP 26 2015 .UPDATE... ISSUED AT 1102 AM CDT SAT SEP 26 2015 ANOTHER UPDATE HAS POSTED. STRATUS CONTS TO LINGER W OF HWY 183. SKY FCST HAS BEEN TRENDED MORE PESSIMISTIC IN THIS AREA...BUT EXPECT GRADUAL IMPROVEMENT AS BREAKS IN THE OVERCAST INCREASE WITH THE STRATUS LIFTING INTO A DECK OF STRATOCU. HIGH TEMPS WERE LOWERED 3-5F W OF HWY 183 WHERE CLOUDS WILL LIMIT HEATING. FOR THE REST OF THE FCST AREA...A VERY NICE DAY IS IN PROGRESS. ENJOY IT! WE WILL BE EVALUATING POTENTIAL FOR FOG REDEVELOPMENT OVER THE W HALF OF THE FCST AREA. TOP/OAX 12Z SOUNDINGS SHOW LOW-LVL DRIER AIR ADVECTING IN FROM THE E. SO IT MIGHT NOT BE A PROBLEM. UPDATE ISSUED AT 728 AM CDT SAT SEP 26 2015 SENT A QUICK UPDATE TO TEMPS/DWPTS/WINDS THRU NOON. OBSERVED TEMPS/DWPTS WERE SVRL DEGS BELOW THE FCST OVER THE NE 1/2 OF THE FCST AREA WHERE SKIES WERE M/CLEAR AND WERE ABOVE THE FCST OVER THE SW 1/2 DUE TO CLOUD COVER. FCST NOW BETTER REFLECTS REALITY. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 345 AM CDT SAT SEP 26 2015 SATELLITE AND OBSERVATIONS SHOW STRATUS ACROSS THE WESTERN TWO THIRDS OF THE FORECAST AREA EARLY THIS MORNING. SO FAR THERE HAVE BEEN A FEW LOCATIONS THAT TEMPORARILY DROP TO LESS THAN A MILE VISIBILITY...BUT THESE SEEM TO BE SHORT LIVED AND AT LEAST SOMEWHAT SPORADIC. THE FIRST CONCERN FOR THE MORNING WILL BE THE FOG. HAVE SOME CONCERN NEAR THE EASTERN EDGE OF THE STRATUS DECK THAT FOG COULD FORM. THE DEW POINT SPREAD IS ONLY A COUPLE OF DEGREES...THE CLEARING SHOULD ALLOW TEMPERATURES TO FALL OFF AND WINDS ARE LIGHT FROM THE EAST. ON THE OTHER HAND...TO THE EAST OF THE STRATUS DECK HAS LOWER DEW POINTS AND A GREATER DEW POINT SPREAD. WINDS ARE STILL LIGHT AND GENERALLY FROM THE EAST. THE LATEST HRRR HAS A SMALL AREA OF LOWER VISIBILITIES A COUPLE HOURS AROUND SUN RISE. THIS AREA IS NEAR THE PROJECTED EDGE OF THE STRATUS AROUND 12Z. WILL CONTINUE TO KEEP THE AREAS OF FOG IN. VISIBILITIES COULD BE AROUND A MILE OR SO AND WILL KEEP IT FOR THE ENTIRE AREA INSTEAD OF GETTING TOO SPECIFIC. THE SHOWERS ACROSS NORTH CENTRAL KANSAS AND FAR SOUTHERN NEBRASKA HAVE ENDED. THERE MAY BE A SPRINKLE OR SO IN A FEW AREAS...BUT DO NOT EXPECT THERE TO BE MUCH OF ANYTHING. WILL REMOVE THE SHOWER CHANCES. A WEAKENING UPPER LEVEL WAVE HAS BEEN DRIFTING TO THE SOUTH OVERNIGHT AND WILL CONTINUE TO MOVE OUT OF THE AREA TODAY. A SURFACE HIGH TO THE EAST WILL CONTINUE TO MOVE TO THE EAST. THE PRESSURE GRADIENT WILL TIGHTEN A LITTLE TODAY AND WINDS WILL TURN TO THE SOUTH AND INCREASE DURING THE DAY. THEY WILL STILL BE FAIRLY LIGHT MAINLY 5 TO 15 MPH. THE MOISTURE WILL DIMINISH AND THE CLOUDS OUT THERE NOW WILL GRADUALLY DIMINISH AND LEAVE MOSTLY SUNNY SKIES. TEMPERATURES THIS AFTERNOON SHOULD BE A LITTLE WARMER THAN YESTERDAY WITH THE SUNSHINE. SKIES WILL REMAIN MOSTLY CLEAR THROUGH THE NIGHT. WINDS WILL BE LIGHT AND DEW POINTS WILL BE LOWER. TEMPERATURES WILL BE A LITTLE COOLER TONIGHT...BUT STILL ABOVE NORMAL FOR THIS TIME OF YEAR. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 401 AM CDT SAT SEP 26 2015 PRIMARY FORECAST CONCERN LIES WITH PRECIPITATION CHANCES. STILL LOOKING AT A DRY END TO THE WEEKEND...WITH MODELS REMAINING IN GOOD AGREEMENT ON SUNDAY...SHOWING THE MAIN UPPER LEVEL RIDGE AXIS CONTINUING TO BE THE MAIN PLAYER ACROSS THE REGION. THIS RIDGE AXIS...SET UP BETWEEN LOW PRESSURE OVER TX AND SHORTWAVE ENERGY MOVING THROUGH THE PAC NW/NRN ROCKIES...EXTENDS FROM HIGH PRESSURE LOCATED OVER THE BAJA THROUGH THE CENTRAL PLAINS. AT THE SFC...EXPECTING SOUTHERLY WINDS TO BE IN PLACE DURING THE DAY...AS THE CWA SITS AHEAD OF AN APPROACHING FRONTAL BOUNDARY. SPEEDS LOOK TO BE ON THE BREEZY SIDE DURING THE AFTERNOON...WITH SPEEDS IN THE 15 TO 20 MPH RANGE. WITH SOME WARMER AIR ALOFT WORKING ITS WAY BACK EAST INTO THE AREA...EXPECTING A BUMP UP IN HIGHS...INTO THE LOWER/MID 80S. STARTING SUNDAY NIGHT AND CONTINUING INTO THE FIRST FEW DAYS OF THE WORK WEEK...UPPER LEVEL ENERGY ASSOCIATED WITH A LOW PRESSURE SYSTEM SLIDING EAST INTO THE HUDSON BAY AREA FURTHER BREAKS DOWN THE MAIN RIDGE AXIS AND STARTS PUSHING IT FURTHER SOUTH. GENERAL AGREEMENT AMONG MODELS SHOW IT LOCATED OVER FAR SRN PORTIONS OF THE CWA/IF NOT JUST SOUTH OF OUR SRN BORDER BY 12Z TUESDAY...WITH MORE ZONAL UPPER LEVEL FLOW IN PLACE BY THEN. THIS SYSTEM WILL ALSO BE PUSHING THAT ABOVE MENTIONED SFC FRONT SOUTH...WITH MODELS NOT IN TOO BAD OF AGREEMENT SHOWING IT BY 12Z MONDAY HAVING MOVED THROUGH A GOOD CHUNK OF OUR SC NEB COUNTIES...AND BY 12Z TUESDAY IS IN THE I-70 AREA OF NRN KS. INCREASED LIFT WITH THIS DISTURBANCE MOVING THROUGH...ALONG WITH MODELS SHOWING MORE FAVORABLE POSITIONING OF UPPER LEVEL JET ENERGY MOVING INTO THE REGION...LOOKS TO BRING PRECIPITATION CHANCES TO THE CWA THROUGH ROUGHLY THE FIRST HALF OF THE WORK WEEK. KEPT THE MAIN AREA OF POPS ACROSS OUR SC NEB COUNTIES...WITH MODELS NOT SHOWING A WHOLE LOT MOVING THROUGH NC KS. HAVE A THUNDER MENTION IN PLACE...WHILE MODELS ARE CERTAINLY NOT SHOWING AN ABUNDANCE OF INSTABILITY...ITS NOT ZERO EITHER. HIGH TEMPERATURES ON MONDAY ARE A BIT TRICKY WITH THAT SFC BOUNDARY CONTINUING TO MOVE SOUTH THROUGH THE DAY...AS WELL AS ON TUESDAY WITH THE POTENTIAL FOR INCREASED CLOUD COVER/PRECIP AFFECTING A GOOD CHUNK OF THE CWA. MODELS SHOWING WARMER TEMPS ALOFT ARE SLOW TO MOVE OUT OF ESP SRN PORTIONS OF THE CWA ON MONDAY...AND HAVE TEMPS RANGING FROM THE MID/UPPER 70S IN THE NORTH TO UPPER 80S SOUTH. TUESDAY LOOKS TO BE COOLER WITH HIGHS IN THE UPPER 60S NORTH TO UPPER 70S SOUTH. HAVE SOME LINGERING 20 POPS IN PLACE ON WED ACROSS NERN PORTIONS OF THE CWA...BUT CONFIDENCE IN WHETHER THEY NEED TO BE THERE AT ALL OR NOT IS NOT HIGH. MODELS ARE SHOWING THAT UPPER LEVEL RIDGING IS STARTING TO BUILD BACK NORTH ACROSS THE ROCKIES/HIGH PLAINS DURING THE DAY...AS HIGH PRESSURE MOVES INTO THE NM/MEX BORDER AREA. THIS RIDGING SLIDES EAST ONTO THE PLAINS AS WE GET INTO THURSDAY...BEING PUSHED BY ANOTHER UPPER LEVEL DISTURBANCE DIGGING SOUTH INTO THE ROCKIES. EXPECTING ANOTHER BUMP BACK UP IN TEMPS...INTO THE UPPER 70S TO MID 80S BY THURSDAY. LOOKING TO THE VERY END OF THIS FORECAST PERIOD THURS NIGHT/FRI...THIS SYSTEM WILL BE LOOKING TO BRING THE NEXT CHANCE FOR PRECIPITATION TO THE REGION...BUT TIMING/LOCATION DETAILS HAVE SOME DETAILS TO BE WORKED OUT IN THE COMING DAYS. && .AVIATION...(FOR THE 12Z KGRI/KEAR TAFS THROUGH 12Z SUN MORNING) ISSUED AT 551 AM CDT SAT SEP 26 2015 STRATUS HAS CONTINUED TO MOVE TO THE WEST OVERNIGHT. KGRI HAS CLEARED OUT AND HAVE REMOVED FOG FROM THE TAF. THE EDGE OF THE STRATUS REMAINS NEAR THE KEAR TERMINAL. THE VISIBILITY HAS BEEN LOWER EARLY THIS MORNING. EXPECT THAT IT SHOULD START TO LIFT AFTER THE SUN COMES UP THIS MORNING. STRATUS SHOULD CONTINUE TO MOVE TO THE WEST AND DISSIPATE THROUGH THE MORNING HOURS. && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$ UPDATE...HALBLAUB SHORT TERM...JCB LONG TERM...ADP AVIATION...JCB
AREA FORECAST DISCUSSION
NWS HASTINGS NE
728 AM CDT SAT SEP 26 2015 .UPDATE... ISSUED AT 728 AM CDT SAT SEP 26 2015 SENT A QUICK UPDATE TO TEMPS/DWPTS/WINDS THRU NOON. OBSERVED TEMPS/DWPTS WERE SVRL DEGS BELOW THE FCST OVER THE NE 1/2 OF THE FCST AREA WHERE SKIES WERE M/CLEAR AND WERE ABOVE THE FCST OVER THE SW 1/2 DUE TO CLOUD COVER. FCST NOW BETTER REFLECTS REALITY. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 345 AM CDT SAT SEP 26 2015 SATELLITE AND OBSERVATIONS SHOW STRATUS ACROSS THE WESTERN TWO THIRDS OF THE FORECAST AREA EARLY THIS MORNING. SO FAR THERE HAVE BEEN A FEW LOCATIONS THAT TEMPORARILY DROP TO LESS THAN A MILE VISIBILITY...BUT THESE SEEM TO BE SHORT LIVED AND AT LEAST SOMEWHAT SPORADIC. THE FIRST CONCERN FOR THE MORNING WILL BE THE FOG. HAVE SOME CONCERN NEAR THE EASTERN EDGE OF THE STRATUS DECK THAT FOG COULD FORM. THE DEW POINT SPREAD IS ONLY A COUPLE OF DEGREES...THE CLEARING SHOULD ALLOW TEMPERATURES TO FALL OFF AND WINDS ARE LIGHT FROM THE EAST. ON THE OTHER HAND...TO THE EAST OF THE STRATUS DECK HAS LOWER DEW POINTS AND A GREATER DEW POINT SPREAD. WINDS ARE STILL LIGHT AND GENERALLY FROM THE EAST. THE LATEST HRRR HAS A SMALL AREA OF LOWER VISIBILITIES A COUPLE HOURS AROUND SUN RISE. THIS AREA IS NEAR THE PROJECTED EDGE OF THE STRATUS AROUND 12Z. WILL CONTINUE TO KEEP THE AREAS OF FOG IN. VISIBILITIES COULD BE AROUND A MILE OR SO AND WILL KEEP IT FOR THE ENTIRE AREA INSTEAD OF GETTING TOO SPECIFIC. THE SHOWERS ACROSS NORTH CENTRAL KANSAS AND FAR SOUTHERN NEBRASKA HAVE ENDED. THERE MAY BE A SPRINKLE OR SO IN A FEW AREAS...BUT DO NOT EXPECT THERE TO BE MUCH OF ANYTHING. WILL REMOVE THE SHOWER CHANCES. A WEAKENING UPPER LEVEL WAVE HAS BEEN DRIFTING TO THE SOUTH OVERNIGHT AND WILL CONTINUE TO MOVE OUT OF THE AREA TODAY. A SURFACE HIGH TO THE EAST WILL CONTINUE TO MOVE TO THE EAST. THE PRESSURE GRADIENT WILL TIGHTEN A LITTLE TODAY AND WINDS WILL TURN TO THE SOUTH AND INCREASE DURING THE DAY. THEY WILL STILL BE FAIRLY LIGHT MAINLY 5 TO 15 MPH. THE MOISTURE WILL DIMINISH AND THE CLOUDS OUT THERE NOW WILL GRADUALLY DIMINISH AND LEAVE MOSTLY SUNNY SKIES. TEMPERATURES THIS AFTERNOON SHOULD BE A LITTLE WARMER THAN YESTERDAY WITH THE SUNSHINE. SKIES WILL REMAIN MOSTLY CLEAR THROUGH THE NIGHT. WINDS WILL BE LIGHT AND DEW POINTS WILL BE LOWER. TEMPERATURES WILL BE A LITTLE COOLER TONIGHT...BUT STILL ABOVE NORMAL FOR THIS TIME OF YEAR. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 401 AM CDT SAT SEP 26 2015 PRIMARY FORECAST CONCERN LIES WITH PRECIPITATION CHANCES. STILL LOOKING AT A DRY END TO THE WEEKEND...WITH MODELS REMAINING IN GOOD AGREEMENT ON SUNDAY...SHOWING THE MAIN UPPER LEVEL RIDGE AXIS CONTINUING TO BE THE MAIN PLAYER ACROSS THE REGION. THIS RIDGE AXIS...SET UP BETWEEN LOW PRESSURE OVER TX AND SHORTWAVE ENERGY MOVING THROUGH THE PAC NW/NRN ROCKIES...EXTENDS FROM HIGH PRESSURE LOCATED OVER THE BAJA THROUGH THE CENTRAL PLAINS. AT THE SFC...EXPECTING SOUTHERLY WINDS TO BE IN PLACE DURING THE DAY...AS THE CWA SITS AHEAD OF AN APPROACHING FRONTAL BOUNDARY. SPEEDS LOOK TO BE ON THE BREEZY SIDE DURING THE AFTERNOON...WITH SPEEDS IN THE 15 TO 20 MPH RANGE. WITH SOME WARMER AIR ALOFT WORKING ITS WAY BACK EAST INTO THE AREA...EXPECTING A BUMP UP IN HIGHS...INTO THE LOWER/MID 80S. STARTING SUNDAY NIGHT AND CONTINUING INTO THE FIRST FEW DAYS OF THE WORK WEEK...UPPER LEVEL ENERGY ASSOCIATED WITH A LOW PRESSURE SYSTEM SLIDING EAST INTO THE HUDSON BAY AREA FURTHER BREAKS DOWN THE MAIN RIDGE AXIS AND STARTS PUSHING IT FURTHER SOUTH. GENERAL AGREEMENT AMONG MODELS SHOW IT LOCATED OVER FAR SRN PORTIONS OF THE CWA/IF NOT JUST SOUTH OF OUR SRN BORDER BY 12Z TUESDAY...WITH MORE ZONAL UPPER LEVEL FLOW IN PLACE BY THEN. THIS SYSTEM WILL ALSO BE PUSHING THAT ABOVE MENTIONED SFC FRONT SOUTH...WITH MODELS NOT IN TOO BAD OF AGREEMENT SHOWING IT BY 12Z MONDAY HAVING MOVED THROUGH A GOOD CHUNK OF OUR SC NEB COUNTIES...AND BY 12Z TUESDAY IS IN THE I-70 AREA OF NRN KS. INCREASED LIFT WITH THIS DISTURBANCE MOVING THROUGH...ALONG WITH MODELS SHOWING MORE FAVORABLE POSITIONING OF UPPER LEVEL JET ENERGY MOVING INTO THE REGION...LOOKS TO BRING PRECIPITATION CHANCES TO THE CWA THROUGH ROUGHLY THE FIRST HALF OF THE WORK WEEK. KEPT THE MAIN AREA OF POPS ACROSS OUR SC NEB COUNTIES...WITH MODELS NOT SHOWING A WHOLE LOT MOVING THROUGH NC KS. HAVE A THUNDER MENTION IN PLACE...WHILE MODELS ARE CERTAINLY NOT SHOWING AN ABUNDANCE OF INSTABILITY...ITS NOT ZERO EITHER. HIGH TEMPERATURES ON MONDAY ARE A BIT TRICKY WITH THAT SFC BOUNDARY CONTINUING TO MOVE SOUTH THROUGH THE DAY...AS WELL AS ON TUESDAY WITH THE POTENTIAL FOR INCREASED CLOUD COVER/PRECIP AFFECTING A GOOD CHUNK OF THE CWA. MODELS SHOWING WARMER TEMPS ALOFT ARE SLOW TO MOVE OUT OF ESP SRN PORTIONS OF THE CWA ON MONDAY...AND HAVE TEMPS RANGING FROM THE MID/UPPER 70S IN THE NORTH TO UPPER 80S SOUTH. TUESDAY LOOKS TO BE COOLER WITH HIGHS IN THE UPPER 60S NORTH TO UPPER 70S SOUTH. HAVE SOME LINGERING 20 POPS IN PLACE ON WED ACROSS NERN PORTIONS OF THE CWA...BUT CONFIDENCE IN WHETHER THEY NEED TO BE THERE AT ALL OR NOT IS NOT HIGH. MODELS ARE SHOWING THAT UPPER LEVEL RIDGING IS STARTING TO BUILD BACK NORTH ACROSS THE ROCKIES/HIGH PLAINS DURING THE DAY...AS HIGH PRESSURE MOVES INTO THE NM/MEX BORDER AREA. THIS RIDGING SLIDES EAST ONTO THE PLAINS AS WE GET INTO THURSDAY...BEING PUSHED BY ANOTHER UPPER LEVEL DISTURBANCE DIGGING SOUTH INTO THE ROCKIES. EXPECTING ANOTHER BUMP BACK UP IN TEMPS...INTO THE UPPER 70S TO MID 80S BY THURSDAY. LOOKING TO THE VERY END OF THIS FORECAST PERIOD THURS NIGHT/FRI...THIS SYSTEM WILL BE LOOKING TO BRING THE NEXT CHANCE FOR PRECIPITATION TO THE REGION...BUT TIMING/LOCATION DETAILS HAVE SOME DETAILS TO BE WORKED OUT IN THE COMING DAYS. && .AVIATION...(FOR THE 12Z KGRI/KEAR TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 551 AM CDT SAT SEP 26 2015 STRATUS HAS CONTINUED TO MOVE TO THE WEST OVERNIGHT. KGRI HAS CLEARED OUT AND HAVE REMOVED FOG FROM THE TAF. THE EDGE OF THE STRATUS REMAINS NEAR THE KEAR TERMINAL. THE VISIBILITY HAS BEEN LOWER EARLY THIS MORNING. EXPECT THAT IT SHOULD START TO LIFT AFTER THE SUN COMES UP THIS MORNING. STRATUS SHOULD CONTINUE TO MOVE TO THE WEST AND DISSIPATE THROUGH THE MORNING HOURS. && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$ UPDATE...HALBLAUB SHORT TERM...JCB LONG TERM...ADP AVIATION...JCB
AREA FORECAST DISCUSSION
NWS HASTINGS NE
555 AM CDT SAT SEP 26 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 345 AM CDT SAT SEP 26 2015 SATELLITE AND OBSERVATIONS SHOW STRATUS ACROSS THE WESTERN TWO THIRDS OF THE FORECAST AREA EARLY THIS MORNING. SO FAR THERE HAVE BEEN A FEW LOCATIONS THAT TEMPORARILY DROP TO LESS THAN A MILE VISIBILITY...BUT THESE SEEM TO BE SHORT LIVED AND AT LEAST SOMEWHAT SPORADIC. THE FIRST CONCERN FOR THE MORNING WILL BE THE FOG. HAVE SOME CONCERN NEAR THE EASTERN EDGE OF THE STRATUS DECK THAT FOG COULD FORM. THE DEW POINT SPREAD IS ONLY A COUPLE OF DEGREES...THE CLEARING SHOULD ALLOW TEMPERATURES TO FALL OFF AND WINDS ARE LIGHT FROM THE EAST. ON THE OTHER HAND...TO THE EAST OF THE STRATUS DECK HAS LOWER DEW POINTS AND A GREATER DEW POINT SPREAD. WINDS ARE STILL LIGHT AND GENERALLY FROM THE EAST. THE LATEST HRRR HAS A SMALL AREA OF LOWER VISIBILITIES A COUPLE HOURS AROUND SUN RISE. THIS AREA IS NEAR THE PROJECTED EDGE OF THE STRATUS AROUND 12Z. WILL CONTINUE TO KEEP THE AREAS OF FOG IN. VISIBILITIES COULD BE AROUND A MILE OR SO AND WILL KEEP IT FOR THE ENTIRE AREA INSTEAD OF GETTING TOO SPECIFIC. THE SHOWERS ACROSS NORTH CENTRAL KANSAS AND FAR SOUTHERN NEBRASKA HAVE ENDED. THERE MAY BE A SPRINKLE OR SO IN A FEW AREAS...BUT DO NOT EXPECT THERE TO BE MUCH OF ANYTHING. WILL REMOVE THE SHOWER CHANCES. A WEAKENING UPPER LEVEL WAVE HAS BEEN DRIFTING TO THE SOUTH OVERNIGHT AND WILL CONTINUE TO MOVE OUT OF THE AREA TODAY. A SURFACE HIGH TO THE EAST WILL CONTINUE TO MOVE TO THE EAST. THE PRESSURE GRADIENT WILL TIGHTEN A LITTLE TODAY AND WINDS WILL TURN TO THE SOUTH AND INCREASE DURING THE DAY. THEY WILL STILL BE FAIRLY LIGHT MAINLY 5 TO 15 MPH. THE MOISTURE WILL DIMINISH AND THE CLOUDS OUT THERE NOW WILL GRADUALLY DIMINISH AND LEAVE MOSTLY SUNNY SKIES. TEMPERATURES THIS AFTERNOON SHOULD BE A LITTLE WARMER THAN YESTERDAY WITH THE SUNSHINE. SKIES WILL REMAIN MOSTLY CLEAR THROUGH THE NIGHT. WINDS WILL BE LIGHT AND DEW POINTS WILL BE LOWER. TEMPERATURES WILL BE A LITTLE COOLER TONIGHT...BUT STILL ABOVE NORMAL FOR THIS TIME OF YEAR. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 401 AM CDT SAT SEP 26 2015 PRIMARY FORECAST CONCERN LIES WITH PRECIPITATION CHANCES. STILL LOOKING AT A DRY END TO THE WEEKEND...WITH MODELS REMAINING IN GOOD AGREEMENT ON SUNDAY...SHOWING THE MAIN UPPER LEVEL RIDGE AXIS CONTINUING TO BE THE MAIN PLAYER ACROSS THE REGION. THIS RIDGE AXIS...SET UP BETWEEN LOW PRESSURE OVER TX AND SHORTWAVE ENERGY MOVING THROUGH THE PAC NW/NRN ROCKIES...EXTENDS FROM HIGH PRESSURE LOCATED OVER THE BAJA THROUGH THE CENTRAL PLAINS. AT THE SFC...EXPECTING SOUTHERLY WINDS TO BE IN PLACE DURING THE DAY...AS THE CWA SITS AHEAD OF AN APPROACHING FRONTAL BOUNDARY. SPEEDS LOOK TO BE ON THE BREEZY SIDE DURING THE AFTERNOON...WITH SPEEDS IN THE 15 TO 20 MPH RANGE. WITH SOME WARMER AIR ALOFT WORKING ITS WAY BACK EAST INTO THE AREA...EXPECTING A BUMP UP IN HIGHS...INTO THE LOWER/MID 80S. STARTING SUNDAY NIGHT AND CONTINUING INTO THE FIRST FEW DAYS OF THE WORK WEEK...UPPER LEVEL ENERGY ASSOCIATED WITH A LOW PRESSURE SYSTEM SLIDING EAST INTO THE HUDSON BAY AREA FURTHER BREAKS DOWN THE MAIN RIDGE AXIS AND STARTS PUSHING IT FURTHER SOUTH. GENERAL AGREEMENT AMONG MODELS SHOW IT LOCATED OVER FAR SRN PORTIONS OF THE CWA/IF NOT JUST SOUTH OF OUR SRN BORDER BY 12Z TUESDAY...WITH MORE ZONAL UPPER LEVEL FLOW IN PLACE BY THEN. THIS SYSTEM WILL ALSO BE PUSHING THAT ABOVE MENTIONED SFC FRONT SOUTH...WITH MODELS NOT IN TOO BAD OF AGREEMENT SHOWING IT BY 12Z MONDAY HAVING MOVED THROUGH A GOOD CHUNK OF OUR SC NEB COUNTIES...AND BY 12Z TUESDAY IS IN THE I-70 AREA OF NRN KS. INCREASED LIFT WITH THIS DISTURBANCE MOVING THROUGH...ALONG WITH MODELS SHOWING MORE FAVORABLE POSITIONING OF UPPER LEVEL JET ENERGY MOVING INTO THE REGION...LOOKS TO BRING PRECIPITATION CHANCES TO THE CWA THROUGH ROUGHLY THE FIRST HALF OF THE WORK WEEK. KEPT THE MAIN AREA OF POPS ACROSS OUR SC NEB COUNTIES...WITH MODELS NOT SHOWING A WHOLE LOT MOVING THROUGH NC KS. HAVE A THUNDER MENTION IN PLACE...WHILE MODELS ARE CERTAINLY NOT SHOWING AN ABUNDANCE OF INSTABILITY...ITS NOT ZERO EITHER. HIGH TEMPERATURES ON MONDAY ARE A BIT TRICKY WITH THAT SFC BOUNDARY CONTINUING TO MOVE SOUTH THROUGH THE DAY...AS WELL AS ON TUESDAY WITH THE POTENTIAL FOR INCREASED CLOUD COVER/PRECIP AFFECTING A GOOD CHUNK OF THE CWA. MODELS SHOWING WARMER TEMPS ALOFT ARE SLOW TO MOVE OUT OF ESP SRN PORTIONS OF THE CWA ON MONDAY...AND HAVE TEMPS RANGING FROM THE MID/UPPER 70S IN THE NORTH TO UPPER 80S SOUTH. TUESDAY LOOKS TO BE COOLER WITH HIGHS IN THE UPPER 60S NORTH TO UPPER 70S SOUTH. HAVE SOME LINGERING 20 POPS IN PLACE ON WED ACROSS NERN PORTIONS OF THE CWA...BUT CONFIDENCE IN WHETHER THEY NEED TO BE THERE AT ALL OR NOT IS NOT HIGH. MODELS ARE SHOWING THAT UPPER LEVEL RIDGING IS STARTING TO BUILD BACK NORTH ACROSS THE ROCKIES/HIGH PLAINS DURING THE DAY...AS HIGH PRESSURE MOVES INTO THE NM/MEX BORDER AREA. THIS RIDGING SLIDES EAST ONTO THE PLAINS AS WE GET INTO THURSDAY...BEING PUSHED BY ANOTHER UPPER LEVEL DISTURBANCE DIGGING SOUTH INTO THE ROCKIES. EXPECTING ANOTHER BUMP BACK UP IN TEMPS...INTO THE UPPER 70S TO MID 80S BY THURSDAY. LOOKING TO THE VERY END OF THIS FORECAST PERIOD THURS NIGHT/FRI...THIS SYSTEM WILL BE LOOKING TO BRING THE NEXT CHANCE FOR PRECIPITATION TO THE REGION...BUT TIMING/LOCATION DETAILS HAVE SOME DETAILS TO BE WORKED OUT IN THE COMING DAYS. && .AVIATION...(FOR THE 12Z KGRI/KEAR TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 551 AM CDT SAT SEP 26 2015 STRATUS HAS CONTINUED TO MOVE TO THE WEST OVERNIGHT. KGRI HAS CLEARED OUT AND HAVE REMOVED FOG FROM THE TAF. THE EDGE OF THE STRATUS REMAINS NEAR THE KEAR TERMINAL. THE VISIBILITY HAS BEEN LOWER EARLY THIS MORNING. EXPECT THAT IT SHOULD START TO LIFT AFTER THE SUN COMES UP THIS MORNING. STRATUS SHOULD CONTINUE TO MOVE TO THE WEST AND DISSIPATE THROUGH THE MORNING HOURS. && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$ SHORT TERM...JCB LONG TERM...ADP AVIATION...JCB
AREA FORECAST DISCUSSION
NWS HASTINGS NE
408 AM CDT SAT SEP 26 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 345 AM CDT SAT SEP 26 2015 SATELLITE AND OBSERVATIONS SHOW STRATUS ACROSS THE WESTERN TWO THIRDS OF THE FORECAST AREA EARLY THIS MORNING. SO FAR THERE HAVE BEEN A FEW LOCATIONS THAT TEMPORARILY DROP TO LESS THAN A MILE VISIBILITY...BUT THESE SEEM TO BE SHORT LIVED AND AT LEAST SOMEWHAT SPORADIC. THE FIRST CONCERN FOR THE MORNING WILL BE THE FOG. HAVE SOME CONCERN NEAR THE EASTERN EDGE OF THE STRATUS DECK THAT FOG COULD FORM. THE DEW POINT SPREAD IS ONLY A COUPLE OF DEGREES...THE CLEARING SHOULD ALLOW TEMPERATURES TO FALL OFF AND WINDS ARE LIGHT FROM THE EAST. ON THE OTHER HAND...TO THE EAST OF THE STRATUS DECK HAS LOWER DEW POINTS AND A GREATER DEW POINT SPREAD. WINDS ARE STILL LIGHT AND GENERALLY FROM THE EAST. THE LATEST HRRR HAS A SMALL AREA OF LOWER VISIBILITIES A COUPLE HOURS AROUND SUN RISE. THIS AREA IS NEAR THE PROJECTED EDGE OF THE STRATUS AROUND 12Z. WILL CONTINUE TO KEEP THE AREAS OF FOG IN. VISIBILITIES COULD BE AROUND A MILE OR SO AND WILL KEEP IT FOR THE ENTIRE AREA INSTEAD OF GETTING TOO SPECIFIC. THE SHOWERS ACROSS NORTH CENTRAL KANSAS AND FAR SOUTHERN NEBRASKA HAVE ENDED. THERE MAY BE A SPRINKLE OR SO IN A FEW AREAS...BUT DO NOT EXPECT THERE TO BE MUCH OF ANYTHING. WILL REMOVE THE SHOWER CHANCES. A WEAKENING UPPER LEVEL WAVE HAS BEEN DRIFTING TO THE SOUTH OVERNIGHT AND WILL CONTINUE TO MOVE OUT OF THE AREA TODAY. A SURFACE HIGH TO THE EAST WILL CONTINUE TO MOVE TO THE EAST. THE PRESSURE GRADIENT WILL TIGHTEN A LITTLE TODAY AND WINDS WILL TURN TO THE SOUTH AND INCREASE DURING THE DAY. THEY WILL STILL BE FAIRLY LIGHT MAINLY 5 TO 15 MPH. THE MOISTURE WILL DIMINISH AND THE CLOUDS OUT THERE NOW WILL GRADUALLY DIMINISH AND LEAVE MOSTLY SUNNY SKIES. TEMPERATURES THIS AFTERNOON SHOULD BE A LITTLE WARMER THAN YESTERDAY WITH THE SUNSHINE. SKIES WILL REMAIN MOSTLY CLEAR THROUGH THE NIGHT. WINDS WILL BE LIGHT AND DEW POINTS WILL BE LOWER. TEMPERATURES WILL BE A LITTLE COOLER TONIGHT...BUT STILL ABOVE NORMAL FOR THIS TIME OF YEAR. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 401 AM CDT SAT SEP 26 2015 PRIMARY FORECAST CONCERN LIES WITH PRECIPITATION CHANCES. STILL LOOKING AT A DRY END TO THE WEEKEND...WITH MODELS REMAINING IN GOOD AGREEMENT ON SUNDAY...SHOWING THE MAIN UPPER LEVEL RIDGE AXIS CONTINUING TO BE THE MAIN PLAYER ACROSS THE REGION. THIS RIDGE AXIS...SET UP BETWEEN LOW PRESSURE OVER TX AND SHORTWAVE ENERGY MOVING THROUGH THE PAC NW/NRN ROCKIES...EXTENDS FROM HIGH PRESSURE LOCATED OVER THE BAJA THROUGH THE CENTRAL PLAINS. AT THE SFC...EXPECTING SOUTHERLY WINDS TO BE IN PLACE DURING THE DAY...AS THE CWA SITS AHEAD OF AN APPROACHING FRONTAL BOUNDARY. SPEEDS LOOK TO BE ON THE BREEZY SIDE DURING THE AFTERNOON...WITH SPEEDS IN THE 15 TO 20 MPH RANGE. WITH SOME WARMER AIR ALOFT WORKING ITS WAY BACK EAST INTO THE AREA...EXPECTING A BUMP UP IN HIGHS...INTO THE LOWER/MID 80S. STARTING SUNDAY NIGHT AND CONTINUING INTO THE FIRST FEW DAYS OF THE WORK WEEK...UPPER LEVEL ENERGY ASSOCIATED WITH A LOW PRESSURE SYSTEM SLIDING EAST INTO THE HUDSON BAY AREA FURTHER BREAKS DOWN THE MAIN RIDGE AXIS AND STARTS PUSHING IT FURTHER SOUTH. GENERAL AGREEMENT AMONG MODELS SHOW IT LOCATED OVER FAR SRN PORTIONS OF THE CWA/IF NOT JUST SOUTH OF OUR SRN BORDER BY 12Z TUESDAY...WITH MORE ZONAL UPPER LEVEL FLOW IN PLACE BY THEN. THIS SYSTEM WILL ALSO BE PUSHING THAT ABOVE MENTIONED SFC FRONT SOUTH...WITH MODELS NOT IN TOO BAD OF AGREEMENT SHOWING IT BY 12Z MONDAY HAVING MOVED THROUGH A GOOD CHUNK OF OUR SC NEB COUNTIES...AND BY 12Z TUESDAY IS IN THE I-70 AREA OF NRN KS. INCREASED LIFT WITH THIS DISTURBANCE MOVING THROUGH...ALONG WITH MODELS SHOWING MORE FAVORABLE POSITIONING OF UPPER LEVEL JET ENERGY MOVING INTO THE REGION...LOOKS TO BRING PRECIPITATION CHANCES TO THE CWA THROUGH ROUGHLY THE FIRST HALF OF THE WORK WEEK. KEPT THE MAIN AREA OF POPS ACROSS OUR SC NEB COUNTIES...WITH MODELS NOT SHOWING A WHOLE LOT MOVING THROUGH NC KS. HAVE A THUNDER MENTION IN PLACE...WHILE MODELS ARE CERTAINLY NOT SHOWING AN ABUNDANCE OF INSTABILITY...ITS NOT ZERO EITHER. HIGH TEMPERATURES ON MONDAY ARE A BIT TRICKY WITH THAT SFC BOUNDARY CONTINUING TO MOVE SOUTH THROUGH THE DAY...AS WELL AS ON TUESDAY WITH THE POTENTIAL FOR INCREASED CLOUD COVER/PRECIP AFFECTING A GOOD CHUNK OF THE CWA. MODELS SHOWING WARMER TEMPS ALOFT ARE SLOW TO MOVE OUT OF ESP SRN PORTIONS OF THE CWA ON MONDAY...AND HAVE TEMPS RANGING FROM THE MID/UPPER 70S IN THE NORTH TO UPPER 80S SOUTH. TUESDAY LOOKS TO BE COOLER WITH HIGHS IN THE UPPER 60S NORTH TO UPPER 70S SOUTH. HAVE SOME LINGERING 20 POPS IN PLACE ON WED ACROSS NERN PORTIONS OF THE CWA...BUT CONFIDENCE IN WHETHER THEY NEED TO BE THERE AT ALL OR NOT IS NOT HIGH. MODELS ARE SHOWING THAT UPPER LEVEL RIDGING IS STARTING TO BUILD BACK NORTH ACROSS THE ROCKIES/HIGH PLAINS DURING THE DAY...AS HIGH PRESSURE MOVES INTO THE NM/MEX BORDER AREA. THIS RIDGING SLIDES EAST ONTO THE PLAINS AS WE GET INTO THURSDAY...BEING PUSHED BY ANOTHER UPPER LEVEL DISTURBANCE DIGGING SOUTH INTO THE ROCKIES. EXPECTING ANOTHER BUMP BACK UP IN TEMPS...INTO THE UPPER 70S TO MID 80S BY THURSDAY. LOOKING TO THE VERY END OF THIS FORECAST PERIOD THURS NIGHT/FRI...THIS SYSTEM WILL BE LOOKING TO BRING THE NEXT CHANCE FOR PRECIPITATION TO THE REGION...BUT TIMING/LOCATION DETAILS HAVE SOME DETAILS TO BE WORKED OUT IN THE COMING DAYS. && .AVIATION...(FOR THE 06Z KGRI/KEAR TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 1221 AM CDT SAT SEP 26 2015 LOW CEILINGS AND VISIBILITIES WILL BE THE MAIN CONCERN. MODELS HAVE SOME DIFFERENCES IN HOW LOW IT WILL GO. THEY ARE CONSISTENT THAT THE LIKELIHOOD OF LOWER CONDITIONS SHOULD BE MORE WEST. HAVE LOWER VISIBILITY AND CEILING FOR KEAR THAN FOR KGRI. WILL HAVE TO WATCH TO SEE WHAT HAPPENS. && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$ SHORT TERM...JCB LONG TERM...ADP AVIATION...JCB
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1133 PM CDT FRI SEP 25 2015 .SHORT TERM...(TONIGHT THROUGH MONDAY) ISSUED AT 230 PM CDT FRI SEP 25 2015 UPPER SYSTEM THAT HAS BEEN RESPONSIBLE FOR DRENCHING RAINS THE PAST FEW DAYS WAS LOCATED OVER NORTHEAST KANSAS AT 19Z. THE SYSTEM WILL CONTINUE TO DRIFT SLOWLY SOUTH TONIGHT BEFORE DISSIPATING OVER THE SOUTHERN PLAINS BY SATURDAY MORNING. CLEARING SKIES ARE EXPECTED TO DEVELOP ACROSS EASTERN NEBRASKA AS THE SYSTEM MOVES OFF AND WEAKENS. LATEST RAP INDICATES LIMITED POTENTIAL FOR FOG SO HAVE REMOVED MENTION FROM FORECAST. GENERAL RIDGING THEN COVERS THE REGION FOR THE WEEKEND WITH FAIR SKIES AND WARM TEMPERATURES EXPECTED ACROSS THE FORECAST AREA. MODELS SIMILAR IN MOVING A COLD FRONT INTO THE REGION ON MONDAY STRETCHING FROM NORTHWEST IOWA INTO SOUTHWEST NEBRASKA BY MONDAY EVENING. LOOKS DRY FOR NOW AHEAD OF THE FRONT ON MONDAY WITH MODELS SHOWING POST FRONTAL SHOWERS FOR MONDAY NIGHT. .LONG TERM...(MONDAY NIGHT THROUGH FRIDAY) ISSUED AT 230 PM CDT FRI SEP 25 2015 PERIODS OF SHOWERS AND THUNDERSTORMS LIKELY MONDAY NIGHT THROUGH TUESDAY AS THE FRONT PUSHES SOUTH. BEYOND THIS TIME THE FORECAST BECOMES LESS CONFIDENT AS GFS AND EURO SHOWING LARGE DIFFERENCES IN SOLUTIONS. EURO BUILDS A RIDGE ACROSS THE CENTRAL PLAINS INTO SOUTHERN CANADA WHILE GFS MAINTAINS A MORE ZONAL FLOW OVER THE MIDDLE OF THE COUNTRY. SMALL POPS COVER MOST OF THE EXTENDED PERIOD AFTER TUESDAY BASED ON MODEL BLENDS. && .AVIATION...(06Z TAFS FOR KOFK...KLNK AND KOMA.) ISSUED AT 1132 PM CDT FRI SEP 25 2015 MAINLY CLEAR SKIES AND LIGHT EAST TO SOUTHEAST WINDS WILL PREVAIL THROUGH THE TAF PERIOD. A BRIEF PERIOD OF MVFR COULD AFFECT TAF SITES AROUND 12Z...BUT SHOULD BE PATCHY AT BEST. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && $$ SHORT TERM...FOBERT LONG TERM...FOBERT AVIATION...DERGAN
AREA FORECAST DISCUSSION
NWS RALEIGH NC
120 AM EDT SAT SEP 26 2015 .SYNOPSIS...DEEP ATLANTIC MOISTURE PUMPING INTO THE REGION... BETWEEN STRONG CANADIAN HIGH PRESSURE TO OUR NORTH AND A LOW PRESSURE TROUGH NEAR THE SOUTHEAST COAST... WILL PRODUCE WET AND UNSETTLED CONDITIONS TODAY AND TONIGHT. GRADUAL DRYING WILL TAKE PLACE SUNDAY AS THE HIGH PRESSURE AREA MOVES OUT OVER THE ATLANTIC. && .NEAR TERM /THROUGH TONIGHT/... AS OF 300 PM FRIDAY... BEST CHANCE OF RAIN THROUGH TONIGHT WILL REMAIN ALONG AND NORTH OF THE I40 CORRIDOR. THE UPPER LEVEL JET STREAK NOW EXTENDING FROM UPSTATE SC INTO SWRN NC WILL TRACK SLOWLY NORTHWARD AND WEAKEN THROUGH TONIGHT... AS THE MID LEVEL LOW TRACKS FROM NW GA NORTHWESTWARD INTO CENTRAL TN WITH LOWERING DPVA OVER CENTRAL NC. ASSOCIATED POTENT UPPER DIVERGENCE WILL SLOWLY DECREASE FROM SW TO NE BUT REMAIN ENHANCED OVER THE FAR NE CWA. WITH A STEADY INFLUX OF DEEP ATLANTIC MOISTURE INTO THIS AREA IN PARTICULAR (INCLUDING A STOUT 925-850 MB JETLET FROM THE ESE) PERSISTING INTO THE NIGHT AND PW VALUES REMAINING WELL ABOVE NORMAL... WILL RETAIN CATEGORICAL POPS IN THE NE CWA... ROUGHLY ALONG AND NORTH/NE OF A LINE FROM INT TO RDU TO GSB. WILL HAVE SLIGHTLY LOWER POPS TO THE SW OF HERE... WITH CONTINUED 295K-305K MOIST ISENTROPIC UPGLIDE AND HIGH MOISTURE INFLUX BUT WANING UPPER LEVEL SUPPORT. THE NSSL-WRF / HRRR / 3KM NAMRR ALL SUPPORT THIS TREND... BOOSTING CONFIDENCE. ADDITIONAL RAINFALL IN THE NE CWA COULD APPROACH AN INCH... BUT IN GENERAL THE WIDESPREAD RAINFALL AMOUNTS WILL BE LIGHT THROUGH TONIGHT... ALBEIT WITH ISOLATED HIGHER TOTALS MAINLY OVER THE NRN CWA. PRECIP SHOULD TREND TO MORE DRIZZLE THAN LIGHT RAIN OVER THE WRN/SRN CWA AS THE AIR DRIES OUT ABOVE -10C... NOTED BY THE RELATIVE DRY SLOT IN WATER VAPOR IMAGERY NOW OVER SC AND WRN NC. THICK CLOUD COVER WILL CONTINUE TO LIMIT THE DIURNAL TEMP RANGE... AND EXPECT LOWS TONIGHT TO BE JUST A CATEGORY OR TWO LOWER THAN CURRENT VALUES... FROM AROUND 60 TO THE UPPER 60S NW TO SE. -GIH && .SHORT TERM /SATURDAY AND SATURDAY NIGHT/... AS OF 325 PM FRIDAY... THE MID LEVEL LOW WILL TRACK FROM CENTRAL TN INTO WRN KY WHILE FILLING AND BECOMING ABSORBED INTO THE BROADER TROUGH EXTENDING FROM THE GREAT LAKES TO A DEVELOPING LOW OVER TX AND NE MEXICO. THIS WILL RESULT IN A TREND FROM A WEAK CYCLONIC MID LEVEL FLOW FROM THE S AND SE TO A MORE ANTICYCLONIC WEAK FLOW FROM THE WSW... WITH DPVA AND UPPER DIVERGENCE BOTH WEAKENING AND SHIFTING NORTH THROUGH SAT NIGHT. MODELS STILL DEPICT ABOVE NORMAL PW... FROM 1.5" NW TO OVER 2.0" EAST OF I95... AND MOIST UPGLIDE CONTINUES BUT TO A BIT LESSER DEGREE (DEPENDING ON THE MODEL)... SO THE THREAT OF PATCHY RAIN SHOULD PERSIST. OVERALL AMOUNTS AND SNAPSHOT COVERAGE SHOULD BE LOWER THAN TODAY HOWEVER... MEANING THAT WHILE MOST PLACES SHOULD SEE MEASURABLE RAIN... IT WON`T BE AS STEADY OR WITH QUITE THE INTENSITY AS WE`VE GOT TODAY. THE EXCEPTION MAY BE OVER COASTAL NC NEAR THE PERSISTENT INVERTED TROUGH... AND WELL TO OUR NW OVER THE SW VA MOUNTAINS WHERE TERRAIN UPLIFT WILL COME INTO PLAY... BUT OTHERWISE CENTRAL NC SHOULD SEE IMPROVING CONDITIONS IN TERMS OF RAINFALL. WILL HAVE CATEGORICAL POPS NE TO LIKELY SW TO START THE DAY... FOLLOWED BY A DOWNWARD TREND TO LIKELY NE AND GOOD CHANCE SW OF LIGHT RAIN AND DRIZZLE LATE SAT INTO SAT NIGHT. ALL INDICATIONS ARE THAT WE`LL STILL HAVE ABUNDANT LOW LEVEL MOISTURE IN PLACE... RESISTANT TO MIXING IN THE VERTICAL (LACK OF BOTH CONVECTION AND SUBSIDENCE) AND HORIZONTALLY (DUE TO THE IN SITU STABLE POOL BEING LOCKED IN OVER THE PIEDMONT/FOOTHILLS BY TERRAIN... THE COASTAL TROUGH... AND LIGHT SURFACE WINDS TO INHIBIT STIRRING). AS SUCH... MOSTLY CLOUDY SKIES WILL REMAIN THE RULE SAT AND SAT NIGHT WITH ONLY A LUCKY FEW (PROBABLY IN THE SE CWA) HAVING A CHANCE FOR SOME SUNSHINE). EXPECT HIGHS MINIMALLY HIGHER THAN TODAY... FROM THE MID 60S TO THE MID 70S NW TO SE. LOWS SAT NIGHT 60-68 WITH WIDESPREAD STRATUS AND LIGHT FOG. -GIH && .LONG TERM /SUNDAY THROUGH THURSDAY/... AS OF 320 PM FRIDAY... IT DOES NOT APPEAR THAT THAT THERE WILL BE A TREMENDOUS AMOUNT OF IMPROVEMENT IN THE SENSIBLE WEATHER ON SUNDAY WITH A SLIGHT IMPROVEMENT FINALLY ARRIVING ON MONDAY. WHILE THE CLOSED LOW ALOFT SHIFTS WEST AND HEIGHTS RISE SLIGHTLY OVER OUR REGION...THE AIRMASS OVER CENTRAL NC REMAINS MOIST THROUGH MONDAY WITH PW VALUES STILL AT OR ABOVE 1.75 INCHES WHICH SHOULD MAINTAIN CONSIDERABLE CLOUDINESS. WIDESPREAD PRECIPITATION SHOULD BE DIMINISHING WITH TIME AND SHIFTING NORTH AS THE BEST FORCING FOR ASCENT CONTINUES TO LIFT INTO THE MID ATLANTIC. WILL HOLD ONTO CHANCE POPS IN AN ARC FROM THE SOUTHERN COASTAL PLAIN NORTHWEST INTO THE VA BORDER COUNTIES WITH SLIGHT CHANCE POPS TO THE SOUTHWEST. HIGHS SUNDAY MAY BE A COUPLE OF DEGREES WARMER THAN SATURDAY BUT HAVE UNDERCUT GUIDANCE SEVERAL DEGREES...ESPECIALLY IN THE TRIAD WHERE A WEDGE AIRMASS REMAINS ESTABLISHED. SUNDAYS HIGHS WILL RANGE IN THE UPPER 60S TO UPPER 70S. HIGHS WILL MODERATE SOME ON MONDAY...ESPECIALLY IN THE NORTHWEST AND NORTHERN PIEDMONT WITH HIGHS IN THE MID 70S NORTHWEST TO LOWER 80S SOUTHEAST. MORNING LOWS ON MONDAY AND TUESDAY MORNING WILL RANGE IN THE 60S. A PERIOD OF SHORT WAVE RIDGING ALOFT ALONG WITH CENTRAL NC BEING LOCATED IN BETWEEN A DEPARTING COASTAL STORM SYSTEM AND A LOW PRESSURE AREA OVER THE GULF OF MEXICO SHOULD LEAD TO A PERIOD OF GENERALLY FAIR WEATHER FOR LATE MONDAY INTO LATE TUESDAY. WE SHOULD SEE SOME BREAKS IN THE OVERCAST WITH JUST A SLIGHT CHANCE OF A SHOWER. THIS SHOULD BE THE DRIEST PERIOD OF THE NEXT 7 DAYS. HIGHS IN THE MID 70S TO AROUND 80 LOOK GOOD. THE WESTERLIES BEGIN TO DROP SOUTH ON WEDNESDAY AND INTO THE LATE WEEK AS THE TROUGH AXIS EXTENDING FROM THE WESTERN GREAT LAKES TO THE WESTERN GULF OF MEXICO BEGINS SHIFTING EAST. THIS SHOULD RESULT IN ANOTHER PERIOD OF UNSETTLED WEATHER LATE WEDNESDAY INTO LATE THURSDAY. HPC GUIDANCE POPS HAVE TRENDED UP NOTABLY AND WE WILL FOLLOW THAT TREND WITH CHANCE POPS AND SLIGHTLY COOLER TEMPERATURES. FRIDAYS FORECAST APPEARS RATHER UNCERTAIN WITH THE NEW OPERATIONAL ECMWF DEVELOPING A SIGNIFICANT COASTAL LOW NEAR THE CAROLINA COAST THE SLOWLY MOVES NORTH ON FRIDAY. THE GFS AND THE GEFS ENSEMBLE MEMBERS DON`T SUPPORT THAT SOLUTION. WILL NEED TO WAIT AND SEE. - BLAES && .AVIATION /06Z SATURDAY THROUGH WEDNESDAY/... AS OF 120 AM SATURDAY... THERE IS A HIGH PROBABILITY THAT SUB VFR CONDITIONS DUE TO CEILINGS AND AREAS OF LIGHT RAIN AND/OR DRIZZLE WILL PERSIST ACROSS CENTRAL NC THROUGH EARLY SUNDAY. IN ADDITION...A STRONG ELY LOW LEVEL JET WILL MAINTAIN A THREAT FOR LOW LEVEL WIND SHEAR THROUGH THIS EVENING AS SFC WINDS REMAIN OUT OF THE NE 8-13KTS. TODAY...WIDESPREAD IFR-LIFR CEILINGS EXPECTED THIS MORNING WITH MAINLY IFR-LOW END MVFR CEILINGS ANTICIPATED FOR THE MID-LATE AFTERNOON HOURS BEFORE LIFR-IFR CEILINGS REDEVELOP AROUND SUNSET. LIGHT RAIN AND/OR DRIZZLE ANTICIPATED TODAY AND TONIGHT. PRECIP INTENSITY AND COVERAGE IS NOT EXPECTED TO BE AS HEAVY OR AS WIDESPREAD AS FRIDAY. THE MURKY AIR MASS EXPECTED TO PERSIST INTO SUNDAY AS WELL WITH LIFR- IFR CEILINGS SUNDAY MORNING SLOWLY IMPROVING TO MVFR BY AFTERNOON. AGAIN...PATCHES OF LIGHT RAIN OR DRIZZLE SHOULD OCCUR...MAINLY IN THE MORNING. A GRADUAL IMPROVEMENT IN AVIATION CONDITIONS EXPECTED MONDAY THROUGH WEDNESDAY...THOUGH PROLONGED PERIODS OF MVFR/IFR CONDITIONS WILL DOMINATE SINCE THE AIR MASS WILL NOT TOTALLY DRY OUT. VFR CONDITIONS WILL BE MOST PROBABLE DURING THE AFTERNOON-EARLY EVENING HOURS. && .HYDROLOGY... AS OF 330 PM FRIDAY... WE`RE STILL GETTING RAINFALL REPORTS IN... BUT BY RADAR ESTIMATION... WE`VE HAD ANYWHERE FROM A QUARTER INCH TO AN INCH AND A HALF ACROSS CENTRAL NC... ENOUGH TO CAUSE SOME TRAFFIC SNARLS AND CONSIDERABLE PONDING OF WATER ON ROADS... BUT NO NOTABLE RIVER OR CREEK FLOODING. ADDITIONAL AMOUNTS COULD APPROACH AN INCH... MAINLY IN THE NRN CWA... BUT OVERALL ANY ADDITIONAL RAIN IS UNLIKELY TO CAUSE FLOODING CONCERNS. THE WET ROADS AND PONDING OF WATER HOWEVER WILL REMAIN A TRAVEL ISSUE THROUGH TONIGHT. -GIH && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...HARTFIELD NEAR TERM...HARTFIELD SHORT TERM...HARTFIELD LONG TERM...BLAES AVIATION...WSS HYDROLOGY...HARTFIELD
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
116 AM EDT SAT SEP 26 2015 .SYNOPSIS... A WEAK TROUGH WILL LINGER NEAR THE COAST THROUGH THE WEEKEND. THE AIRMASS WILL BE RELUCTANT TO DRY OUT UNTIL THE PASSAGE OF A COLD FRONT LATE NEXT WEEK. THIS WILL KEEP SKIES CONSIDERABLY CLOUDY WITH A DAILY RISK FOR SHOWERS FOR MUCH OF THE PERIOD. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... AS OF 130 AM SATURDAY...NO CHANGES TO THE FORECAST WITH THE LATEST UPDATE. PREVIOUS DISCUSSIONS FOLLOW: NO SIGNIFICANT CHANGES WERE MADE WITH THIS UPDATE. TWEAKED PRECIP TO FIT EXTRAPOLATED TRENDS FROM THE CURRENT RADAR...AND ADJUSTED CLOUD COVER DOWN FOR THE NEXT COUPLE OF HOURS NEAR THE SANTEE RIVER WHERE SKIES ARE PROBABLY PARTLY CLOUDY AT WORST CURRENTLY. NO SIGNIFICANT CHANGES WERE MADE TO TEMPERATURES EITHER. DISCUSSION FROM 730 PM FOLLOWS... THE UPPER LEVEL LOW OVER NORTH GEORGIA IS BEGINNING TO RETROGRADE TOWARD CENTRAL TENNESSEE...MAINTAINING A SOUTHERLY MID AND UPPER LEVEL FLOW ACROSS THE AREA. THE SURFACE LOW THAT CAME ASHORE IN SOUTH CAROLINA EARLIER THIS MORNING IS DISSIPATING ACROSS EAST- CENTRAL GEORGIA. A NEW TROUGH OF LOW PRESSURE HAS DEVELOPED OVER EASTERN SOUTH CAROLINA EXTENDING EASTWARD OFF THE COAST SOUTH OF CAPE FEAR. THIS FEATURE WILL BE WITH US MUCH OF THE WEEKEND...HELPING MAINTAIN SHOWER CHANCES. THE PRESSURE GRADIENT IS QUITE TIGHT ACROSS NORTHERN AND CENTRAL NORTH CAROLINA DUE TO LARGE HIGH PRESSURE CENTERED OVER SOUTHERN HUDSON BAY CANADA. THIS HIGH IS ATTEMPTING TO BUILD SOUTHWARD BUT IS BEING HELD BACK BY THE OLD LOW OVER GEORGIA AND THE OFFSHORE TROUGH. THE HIGH SHOULD BUILD A LITTLE FARTHER SOUTH OVERNIGHT BRINGING SOME OF THE NORTHEASTERLY BREEZES DOWN INTO NORTHERNMOST SOUTH CAROLINA OVERNIGHT. ALONG THE BEACHES WIND GUSTS OVER 20 MPH ARE EXPECTED...ESPECIALLY NORTH OF CAPE FEAR. SHOWERS ARE CURRENTLY MOST WIDESPREAD WELL NORTH OF THE TROUGH WHERE SHALLOW ISENTROPIC LIFT ALONG THE 300K THETA SURFACE EXISTS. ITS INTERESTING THAT THE FLOW CHANGES DIRECTION CONSIDERABLY BETWEEN THE 300K AND 305K SURFACES...EASTERLY VS. SOUTHEASTERLY... HELPING EXPLAIN THE DIFFERENCE IN OBSERVED MOVEMENT BETWEEN THE SHALLOW LIGHT SHOWERS AND THE DEEPER CONVECTIVE COLUMNS THAT HAVE A MORE NORTHWARD MOVEMENT. THE HRRR/RUC MODELS SHOW THE BETTER POTENTIAL FOR SHOWERS CONTINUING ACROSS SE NORTH CAROLINA PLUS THE NORTHERN PEE DEE REGION OF SOUTH CAROLINA...AND POPS ACROSS THIS REGION ARE IN THE 60-80 PERCENT RANGE. POPS ARE LESS...20-40 PERCENT...NEAR AND SOUTH OF MYRTLE BEACH AND LAKE CITY. LOWS TONIGHT SHOULD REMAIN RATHER WARM FOR THIS LATE IN THE YEAR...NEAR 68-70 WITH LOWER 70S AT THE COAST. && .SHORT TERM /6 AM THIS MORNING THROUGH SUNDAY NIGHT/... AS OF 300 PM FRIDAY...THE MAIN JET WILL REMAIN ALONG AND NORTH OF THE CANADIAN BORDER THROUGH THE PERIOD. AN UPPER LOW ACROSS GEORGIA TODAY WILL REMAIN W OF THE EASTERN CAROLINAS...ENDING UP NEAR THE TEXAS COAST SUNDAY. WEAK RIDING ALOFT WILL POKE INTO THE CAROLINAS SUN...AN EXTENSION OF ATLANTIC HIGH PRESSURE. A STRONG SURFACE HIGH OVER NEW ENGLAND WILL WEDGE ACROSS THE WESTERN CAROLINAS. HOWEVER...A WEAK FRONT/TROUGH WILL REMAIN NEAR THE CAROLINA COAST THROUGH THE WEEKEND. GIVEN THE PERSISTENT ONSHORE FLOW THROUGH 25 KFT OR SO...EXPECT CLOUDS WILL BE PLENTIFUL. HOWEVER DEVELOPING BREAKS IN THE CLOUDS SHOULD HELP TO INCREASE INSTABILITY...AND MODELS DO SHOW CAPE VALUES INCREASING TO 500 J/KG OR GREATER ACROSS PORTIONS OF THE AREA. PRECIPITABLE WATER VALUES WILL REMAIN HIGH...1.75 TO 2 INCHES THROUGH THE PERIOD. THE MOISTURE DEPTH WILL BE DEEPEST NEARER TO THE COAST..ESPECIALLY ON SAT. THE BEST ISENTROPIC LIFT WILL BE N OF THE FORECAST AREA SAT AND SIGNIFICANT SHORTWAVE ENERGY WILL BE ROTATING AROUND UPPER LOW...WELL TO OUR W AND THIS SUGGESTS LESS IN THE WAY OF RAINFALL. AT THIS TIME...WILL CARRY LOWEST POPS ACROSS THE PEE DEE REGION...CHANCE ON SAT AND HIGHEST POPS ACROSS THE CAPE FEAR COAST...MAINLY LIKELY. WILL THEN TREND POPS LOWER THROUGH THE REMAINDER OF THE WEEKEND AS SOMEWHAT DRIER AIR STRUGGLES TO MAKE INROADS THIS FAR EAST. THAT BEING SAID...CAN NOT KEEP MENTION OF SHOWERS OUT OF THE FORECAST FOR SUNDAY AND STILL EXPECT CONSIDERABLE CLOUD COVER. CLOUDS AND ONSHORE FLOW WILL SHRINK THE DIURNAL RANGE WITH HIGHS IN THE UPPER 70S TO AROUND 80 AND LOWS IN THE MID 60S TO NEAR 70. && .LONG TERM /MONDAY THROUGH FRIDAY/... AS OF 300 PM FRIDAY...THE MID LEVEL PATTERN WILL BE RELATIVELY WEAK THROUGH THE FIRST PART OF THE PERIOD...MONDAY THROUGH WEDNESDAY AS THE LOW PRESSURE THAT IS CURRENTLY IN THE TENNESSEE VALLEY RETROGRADES AND DEVELOPS INTO A LARGER SYSTEM OVER TEXAS. THE BERMUDA RIDGE WILL BUILD IN FROM THE EAST. BY LATER WEDNESDAY THIS LOW PHASES WITH A WEAK SHORTWAVE TO THE NORTH AND MOVES TO THE EAST ALONG WITH THE ATTENDANT COLD FRONT. THIS FRONT SHOULD MOVE ACROSS LATE THURSDAY INTO FRIDAY. POPS ARE IN THE PICTURE EACH DAY WITH THE SOUTHERLY FLOW BETWEEN SYSTEMS MONDAY THROUGH WEDNESDAY WITH SLIGHTLY HIGHER VALUES WEDNESDAY AND THURSDAY. BY FRIDAY POPS DROP CONSIDERABLY BUT WILL MAINTAIN A SLIGHT CHANCE TO ADDRESS INHERENT UNCERTAINTY WITH THE TIMING OF THE FRONT. NO REAL HEADLINERS OR DRAMATIC CHANGES FOR TEMPERATURES WHICH WILL REMAIN SOMEWHAT ABOVE CLIMATOLOGY FOR OVERNIGHT LOWS AND NEAR SEASONAL VALUES FOR DAYTIME HIGHS. && .AVIATION /06Z SATURDAY THROUGH WEDNESDAY/... AS OF 06Z...BROAD UPPER LOW QUITE VISIBLE ON WATER VAPOR MOVING SLOWLY NORTH NORTHWEST INTO TENNESSEE. A BROAD BAND OF DEEP MOISTURE IS EXTENDING SOUTH SOUTHEASTWARD FROM THE UPPER LOW. MODELS ARE IN REASONABLE AGREEMENT IN THAT THIS LARGE BAND OF MOISTURE WILL ONLY AFFECT THE EXTREME NORTHEASTERN PORTION OF THE CWA THROUGH THE NEXT 24 HOURS. A VCSH MENTION WOULD LIKELY SUFFICE FOR ALL TERMINALS...BUT THERE PROBABLY WILL BE AN ISOLATED SHOWER OR TWO AT ONE OR MORE OF THE TERMINALS. NEAR IFR CONDITIONS WILL LIKELY BECOME SOLIDLY IFR AS WE HEAD FURTHER INTO THE EVENING...WITH IFR CONDITIONS THROUGH THE OVERNIGHT HOURS. SATURDAY...IFR CEILINGS WILL SLOWLY LIFT TO MVFR...WITH STILL A THREAT OF ISOLATED TO SCATTERED CONVECTION. AGAIN IF WE HEAT UP WITH SOME SOLAR INSOLATION...MORE CONVECTION IS POSSIBLE PARTICULARLY OVER THE NORTHEAST PORTION OF THE CWA. CONTINUED NORTHEAST FLOW THROUGH THE PERIOD. EXTENDED OUTLOOK...INTERMITTENT IFR CONDITIONS ARE POSSIBLE THROUGH SATURDAY EVENING. IMPROVING CONDITIONS SUNDAY AND MONDAY WITH DETERIORATING CONDITIONS AGAIN LATE TUESDAY THROUGH WEDNESDAY. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 130 AM SATURDAY...NO CHANGES TO THE FORECAST WITH THE LATEST UPDATE. PREVIOUS DISCUSSION FOLLOWS: LATEST WIND GUSTS ARE STILL EXCEEDING 20 KNOTS ALONG THE BEACHES NORTH OF CAPE FEAR. WE`RE REALLY MISSING THAT WAVE HEIGHT DATA FROM THE NEARSHORE WRIGHTSVILLE BEACH BUOY (NOAA ID 41038) WHICH WAS DAMAGED BY A FISHING BOAT A MONTH OR SO AGO. LATEST HRRR AND RUC STILL HAVE THE TRENDS RIGHT AND VERY FEW CHANGES WERE NEEDED TO THE FORECAST. I DID INCREASE WIND SPEEDS TO 15-20 KT SUSTAINED NORTH OF CAPE FEAR. DISCUSSION FROM 730 PM FOLLOWS... WE ARE ALREADY BEGINNING TO SEE SIGNS THAT A NOCTURNAL NORTHEASTERLY SURGE IS TAKING SHAPE AGAIN BETWEEN CAPE FEAR AND CAPE LOOKOUT. FOR EACH OF THE PAST THREE NIGHTS WIND SPEEDS HAVE ACCELERATED WELL BEYOND MODEL FORECASTS AT ALL COASTAL OBSERVATION PLATFORMS IN ONSLOW BAY. I HAVE INCREASED WIND SPEED FORECASTS TO A SOLID 15 KNOTS IN THIS AREA WITH SEAS HOLDING AT A CHOPPY 4 FEET. SOUTH OF CAPE FEAR EAST TO NORTHEAST WINDS 10-15 KT SHOULD PREDOMINATE WITH SEAS 2-4 FEET. A WEAK TROUGH OF LOW PRESSURE OFFSHORE IS COMPRESSING THE PRESSURE GRADIENT UP AGAINST A LARGE CANADIAN HIGH CENTERED OVER SOUTHERN HUDSON BAY IN CANADA. THIS PATTERN SHOULD CONTINUE THROUGH MOST OF THE WEEKEND. SHOWER ACTIVITY IS VERY LIGHT...BUT A CONDITIONALLY UNSTABLE AND VERY MOIST AIRMASS COULD DEVELOP SCATTERED SHOWERS AT ALMOST ANY TIME THROUGH THE NIGHT. THE BEST POTENTIAL FOR SHOWERS IS NORTH OF CAPE FEAR. SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/... AS OF 300 PM FRIDAY...A TROUGH/WEAK FRONT WILL PERSIST NEAR THE WATERS AND MAY OSCILLATE ACROSS THE WATERS WITH HEATING. THE WIND DIRECTION WILL BE EASTERLY...ENE TO ESE THROUGH THE PERIOD. THE PRESSURE GRADIENT STILL DOES NOT APPEAR SIGNIFICANT ACROSS THE WATERS AND THIS SHOULD KEEP WIND SPEEDS NEAR OR BELOW 15 KT THROUGH THE PERIOD. THE PERSISTENT EASTERLY FLOW WILL INCREASE SWELL ENERGY AND WITH THAT...SEAS WILL REMAIN 3 TO 5 FT THROUGH THE PERIOD ACROSS THE NORTHERN WATERS AND 3 TO 4 FT ACROSS THE SOUTHERN WATERS. SMALL CRAFT SHOULD EXERCISE CAUTION CONDITIONS ARE POSSIBLE. LONG TERM /MONDAY THROUGH WEDNESDAY/... AS OF 300 PM FRIDAY...GENERALLY LIGHT WIND FIELDS THROUGH THE PERIOD AND THE SYNOPTIC DIRECTION WILL BE FROM THE NORTHEAST AS WEAK HIGH PRESSURE CONTINUES TO NOSE DOWN INTO THE AREA. THE WEAKLY FORCED WINDS WILL LEAD TO SEA BREEZE CIRCULATIONS EACH AFTERNOON WITH THE DIRECTION TURNING TO EASTERLY AND POSSIBLY TO THE SOUTHEAST FOR A FEW HOURS. ALL SPEEDS SHOULD BE ON THE LOWER END OF A 10-15 KNOT RANGE. SIGNIFICANT SEAS WILL BE 2-3 FEET. && .TIDES/COASTAL FLOODING... AS OF 1030 PM FRIDAY...HIGH TIDES ASSOCIATED WITH THE FULL MOON AND NORTHEAST WINDS REACHED 5.99 FEET MLLW AT WRIGHTSVILLE BEACH...7.39 FEET MLLW AT MYRTLE BEACH...AND 5.82 FEET MLLW AT DOWNTOWN WILMINGTON ON THE CAPE FEAR RIVER. TIDES WILL REMAIN HIGHER THAN NORMAL FOR THE NEXT FEW DAYS...WITH MINOR COASTAL FLOODING POSSIBLE WITH EACH OF THE EVENING HIGH TIDES THROUGH MONDAY. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...NONE. && $$ SYNOPSIS...RJD NEAR TERM...REK/TRA SHORT TERM...RJD LONG TERM...SHK AVIATION...DL MARINE...REK/RJD/TRA/SHK TIDES/COASTAL FLOODING...99
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1232 PM CDT SAT SEP 26 2015 .UPDATE... ISSUED AT 1235 PM CDT SAT SEP 26 2015 NO MAJOR CHANGES NEEDED. SOUTHERLY WINDS CONTINUE TO SLOWLY INCREASE WITH FULL SUNSHINE EXPECTED TODAY. && .SHORT TERM...(TODAY THROUGH SUNDAY) ISSUED AT 333 AM CDT SAT SEP 26 2015 PRETTY STABLE SITUATION EARLY THIS MORNING. WESTERN EDGE OF LOWER CLOUDS THAT MOVED BACK WEST LAST EVENING LOCATED NEAR BAUDETTE TO BEMIDJI TO PARK RAPIDS. THE WESTERN EDGE HASNT MOVED MUCH SINCE 06Z AND IN LINE WITH THE LATEST HRRR MODEL PROG. SOUTHERLY WINDS 10 TO 20 KTS IN THE RRV AND ERN ND KEEPING TEMPS QUITE MILD FOR THIS TIME OF YEAR. SOME CIRRUS MOVING OVER TOP OF THE UPPER RIDGE THRU THE AREA...THOUGH MORE SCATTERED AND THIN. TODAY WILL BE A WARM DAY AND IT WILL BE WINDY. 925 MB WINDS PICK UP TO 35 TO 40 KTS IN THE NRN VALLEY MIDDAY-AFTN. SOUTHERLY FLOW AND CURRENT SFC PATTERN FAVORS HIGHEST WINDS TODAY IN THE NRN VALLEY...CENTERED ON HALLOCK TO WINNIPEG. BASED ON HIGHER WIND SPEEDS GIVEN BY GFS MOS AND LAV MOS GUIDANCE...ISSUED A WIND ADVISORY 17Z-00Z FOR THE NRN RRV. WINDS ELSEWHERE LOOK TO HOLD JUST SHY OF ADVISORY LEVELS. SOME CIRRUS AT TIMES TODAY BUT OTHERWISE ONCE THE LOW CLOUDS BURN OFF IN THE FAR EAST....LOTS OF SUN TODAY. WENT WITH A BIT WARMER GUIDANCE WHICH SHOWS 80-84 IN RRV AND ERN ND. WINDS TO HOLD UP TONIGHT AHEAD OF SFC COLD FRONT WHICH WILL ENTER NW ND/SW MANITOBA OVERNIGHT. THE COLD FRONT WILL MOVE EAST AND SOUTHEAST SUNDAY THROUGH THE AREA. MOISTURE IS LIMITED TO ALONG THE INTL BORDER AND INTO CANADA. WILL MAINTAIN CHC POPS MAINLY ALONG AND NORTH OF HWY 2. SOME WEAK CAPE AND SHOWALTERS AROUND ZERO AND SPC DAY 2 T-STORM OUTLOOK ALL LEAD TO MENTION OF ISOLD THUNDER IN NW MN/NRN RRV SUN AFTN. OVERALL THOUGH A MINOR PRECIP EVENT. .LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY) ISSUED AT 333 AM CDT SAT SEP 26 2015 SIGNIFICANTLY COOLER AIR TO FOLLOW SUNDAY NIGHT INTO MONDAY AS HIGH PRESSURE BUILD SOUTH. CONSENSUS FROM 00Z MODELS IS NOW TO KEEP ALL PRECIP TO OUR SOUTH MONDAY-MONDAY NIGHT AS HIGH SETTLES OVER THE AREA. THUS COORD WITH OTHER OFFICES LED TO REMOVAL OF ANY POPS MON-MON NIGHT. MONDAY NIGHT-EARLY TUESDAY MORNING MAY WELL BRING A FROST TO SOME AREAS AS LOWS IN THE MID 30S MAY WELL BE PRETTY COMMON IN NE ND/NW MN. LEFT OUT FROST WORDING FOR NOW AS SO MANY VARIABLES AT PLAY YET. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 1235 PM CDT SAT SEP 26 2015 VFR CONDITIONS EXPECTED THROUGH THE PERIOD. STRONG SOUTHERLY WINDS GUSTING NEAR OR ABOVE 30 KTS EXPECTED THIS AFTERNOON...HIGHEST RRV WESTWARD...WITH WINDS REMAINING BREEZY TO GUSTY TONIGHT. A COLD FRONT WILL MOVE THROUGH KDVL SUNDAY MORNING...AND APPROACH KGFK/KTVF/KFAR NEAR THE END OF THIS TAF PERIOD. PRECIP CHANCES WITH THE FRONTAL PASSAGE APPEAR TOO LOW TO MENTION. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...WIND ADVISORY UNTIL 7 PM CDT THIS EVENING FOR NDZ006>008-014>016- 024-026>030-054. MN...WIND ADVISORY UNTIL 7 PM CDT THIS EVENING FOR MNZ001-004-007. && $$ UPDATE...DK SHORT TERM...RIDDLE LONG TERM...WJB/RIDDLE AVIATION...MAKOWSKI
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1012 AM CDT SAT SEP 26 2015 .UPDATE... ISSUED AT 1010 AM CDT SAT SEP 26 2015 WE HAVE EXPANDED THE WIND ADVISORY TO INCLUDE THE DEVILS LAKE BASIN AND GRIGGS COUNTY. THERE WILL BE ABOUT 40KT TO MIX EFFICIENTLY IN THE ADVISORY AREA...WITH GUSTS TO NEAR 50 MPH AT TIMES. THE REST OF THE FORECAST LOOKS GOOD TODAY. && .SHORT TERM...(TODAY THROUGH SUNDAY) ISSUED AT 333 AM CDT SAT SEP 26 2015 PRETTY STABLE SITUATION EARLY THIS MORNING. WESTERN EDGE OF LOWER CLOUDS THAT MOVED BACK WEST LAST EVENING LOCATED NEAR BAUDETTE TO BEMIDJI TO PARK RAPIDS. THE WESTERN EDGE HASNT MOVED MUCH SINCE 06Z AND IN LINE WITH THE LATEST HRRR MODEL PROG. SOUTHERLY WINDS 10 TO 20 KTS IN THE RRV AND ERN ND KEEPING TEMPS QUITE MILD FOR THIS TIME OF YEAR. SOME CIRRUS MOVING OVER TOP OF THE UPPER RIDGE THRU THE AREA...THOUGH MORE SCATTERED AND THIN. TODAY WILL BE A WARM DAY AND IT WILL BE WINDY. 925 MB WINDS PICK UP TO 35 TO 40 KTS IN THE NRN VALLEY MIDDAY-AFTN. SOUTHERLY FLOW AND CURRENT SFC PATTERN FAVORS HIGHEST WINDS TODAY IN THE NRN VALLEY...CENTERED ON HALLOCK TO WINNIPEG. BASED ON HIGHER WIND SPEEDS GIVEN BY GFS MOS AND LAV MOS GUIDANCE...ISSUED A WIND ADVISORY 17Z-00Z FOR THE NRN RRV. WINDS ELSEWHERE LOOK TO HOLD JUST SHY OF ADVISORY LEVELS. SOME CIRRUS AT TIMES TODAY BUT OTHERWISE ONCE THE LOW CLOUDS BURN OFF IN THE FAR EAST....LOTS OF SUN TODAY. WENT WITH A BIT WARMER GUIDANCE WHICH SHOWS 80-84 IN RRV AND ERN ND. WINDS TO HOLD UP TONIGHT AHEAD OF SFC COLD FRONT WHICH WILL ENTER NW ND/SW MANITOBA OVERNIGHT. THE COLD FRONT WILL MOVE EAST AND SOUTHEAST SUNDAY THROUGH THE AREA. MOISTURE IS LIMITED TO ALONG THE INTL BORDER AND INTO CANADA. WILL MAINTAIN CHC POPS MAINLY ALONG AND NORTH OF HWY 2. SOME WEAK CAPE AND SHOWALTERS AROUND ZERO AND SPC DAY 2 T-STORM OUTLOOK ALL LEAD TO MENTION OF ISOLD THUNDER IN NW MN/NRN RRV SUN AFTN. OVERALL THOUGH A MINOR PRECIP EVENT. .LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY) ISSUED AT 333 AM CDT SAT SEP 26 2015 SIGNIFICANTLY COOLER AIR TO FOLLOW SUNDAY NIGHT INTO MONDAY AS HIGH PRESSURE BUILD SOUTH. CONSENSUS FROM 00Z MODELS IS NOW TO KEEP ALL PRECIP TO OUR SOUTH MONDAY-MONDAY NIGHT AS HIGH SETTLES OVER THE AREA. THUS COORD WITH OTHER OFFICES LED TO REMOVAL OF ANY POPS MON-MON NIGHT. MONDAY NIGHT-EARLY TUESDAY MORNING MAY WELL BRING A FROST TO SOME AREAS AS LOWS IN THE MID 30S MAY WELL BE PRETTY COMMON IN NE ND/NW MN. LEFT OUT FROST WORDING FOR NOW AS SO MANY VARIABLES AT PLAY YET. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 657 AM CDT SAT SEP 26 2015 VFR THRU THE FCST PD. LOW CLOUDS EXITING BEMIDJI AT 12Z. SOUTH WINDS TO TAKE CONTROL TODAY AND INCREASE TO THE 15 TO 30 KT RANGE IN THE RED RIVER VALLEY AND EASTERN ND. SOME CIRRUS AT TIMES THIS AFTN AND TONIGHT. WINDS LIKELY TO REMAIN GUSTY INTO TONIGHT. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...WIND ADVISORY UNTIL 7 PM CDT THIS EVENING FOR NDZ006>008-014>016- 024-026>030-054. MN...WIND ADVISORY UNTIL 7 PM CDT THIS EVENING FOR MNZ001-004-007. && $$ UPDATE...DK SHORT TERM...RIDDLE LONG TERM...WJB/RIDDLE AVIATION...RIDDLE
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
659 AM CDT SAT SEP 26 2015 .UPDATE... ISSUED AT 657 AM CDT SAT SEP 26 2015 LOW CLOUDS CLEARING OUT OF THE FAR EASTERN FCST AREA....SO UPDATED SKY COVER TO REFLECT FASTER CLEARING. OTHERWISE MAINLY CLEAR SKY THIS MORNING. NO OTHER CHANGES. && .SHORT TERM...(TODAY THROUGH SUNDAY) ISSUED AT 333 AM CDT SAT SEP 26 2015 PRETTY STABLE SITUATION EARLY THIS MORNING. WESTERN EDGE OF LOWER CLOUDS THAT MOVED BACK WEST LAST EVENING LOCATED NEAR BAUDETTE TO BEMIDJI TO PARK RAPIDS. THE WESTERN EDGE HASNT MOVED MUCH SINCE 06Z AND IN LINE WITH THE LATEST HRRR MODEL PROG. SOUTHERLY WINDS 10 TO 20 KTS IN THE RRV AND ERN ND KEEPING TEMPS QUITE MILD FOR THIS TIME OF YEAR. SOME CIRRUS MOVING OVER TOP OF THE UPPER RIDGE THRU THE AREA...THOUGH MORE SCATTERED AND THIN. TODAY WILL BE A WARM DAY AND IT WILL BE WINDY. 925 MB WINDS PICK UP TO 35 TO 40 KTS IN THE NRN VALLEY MIDDAY-AFTN. SOUTHERLY FLOW AND CURRENT SFC PATTERN FAVORS HIGHEST WINDS TODAY IN THE NRN VALLEY...CENTERED ON HALLOCK TO WINNIPEG. BASED ON HIGHER WIND SPEEDS GIVEN BY GFS MOS AND LAV MOS GUIDANCE...ISSUED A WIND ADVISORY 17Z-00Z FOR THE NRN RRV. WINDS ELSWHERE LOOK TO HOLD JUST SHY OF ADVISORY LEVELS. SOME CIRRUS AT TIMES TODAY BUT OTHERWISE ONCE THE LOW CLOUDS BURN OFF IN THE FAR EAST....LOTS OF SUN TODAY. WENT WITH A BIT WARMER GUIDANCE WHICH SHOWS 80-84 IN RRV AND ERN ND. WINDS TO HOLD UP TONIGHT AHEAD OF SFC COLD FRONT WHICH WILL ENTER NW ND/SW MANITOBA OVERNIGHT. THE COLD FRONT WILL MOVE EAST AND SOUTHEAST SUNDAY THROUGH THE AREA. MOISTURE IS LIMITED TO ALONG THE INTL BORDER AND INTO CANADA. WILL MAINTAIN CHC POPS MAINLY ALONG AND NORTH OF HWY 2. SOME WEAK CAPE AND SHOWWALTERS AROUND ZERO AND SPC DAY 2 T-STORM OUTLOOK ALL LEAD TO MENTION OF ISOLD THUNDER IN NW MN/NRN RRV SUN AFTN. OVERALL THOUGH A MINOR PRECIP EVENT. .LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY) ISSUED AT 333 AM CDT SAT SEP 26 2015 SIGNIFICANTLY COOLER AIR TO FOLLOW SUNDAY NIGHT INTO MONDAY AS HIGH PRESSURE BUILD SOUTH. CONSENSUS FROM 00Z MODELS IS NOW TO KEEP ALL PRECIP TO OUR SOUTH MONDAY-MONDAY NIGHT AS HIGH SETTLES OVER THE AREA. THUS COORD WITH OTHER OFFICES LED TO REMOVAL OF ANY POPS MON-MON NIGHT. MONDAY NIGHT-EARLY TUESDAY MORNING MAY WELL BRING A FROST TO SOME AREAS AS LOWS IN THE MID 30S MAY WELL BE PRETTY COMMON IN NE ND/NW MN. LEFT OUT FROST WORDING FOR NOW AS SO MANY VARIABLES AT PLAY YET. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 657 AM CDT SAT SEP 26 2015 VFR THRU THE FCST PD. LOW CLOUDS EXITING BEMIDJI AT 12Z. SOUTH WINDS TO TAKE CONTROL TODAY AND INCREASE TO THE 15 TO 30 KT RANGE IN THE RED RIVER VALLEY AND EASTERN ND. SOME CIRRUS AT TIMES THIS AFTN AND TONIGHT. WINDS LIKELY TO REMAIN GUSTY INTO TONIGHT. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...WIND ADVISORY FROM NOON TODAY TO 7 PM CDT THIS EVENING FOR NDZ007-008-016-026-027-029-030-054. MN...WIND ADVISORY FROM NOON TODAY TO 7 PM CDT THIS EVENING FOR MNZ001-004-007. && $$ UPDATE...RIDDLE SHORT TERM...RIDDLE LONG TERM...WJB/RIDDLE AVIATION...RIDDLE
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
342 AM CDT SAT SEP 26 2015 .SHORT TERM...(TODAY THROUGH SUNDAY) ISSUED AT 333 AM CDT SAT SEP 26 2015 PRETTY STABLE SITUATION EARLY THIS MORNING. WESTERN EDGE OF LOWER CLOUDS THAT MOVED BACK WEST LAST EVENING LOCATED NEAR BAUDETTE TO BEMIDJI TO PARK RAPIDS. THE WESTERN EDGE HASNT MOVED MUCH SINCE 06Z AND IN LINE WITH THE LATEST HRRR MODEL PROG. SOUTHERLY WINDS 10 TO 20 KTS IN THE RRV AND ERN ND KEEPING TEMPS QUITE MILD FOR THIS TIME OF YEAR. SOME CIRRUS MOVING OVER TOP OF THE UPPER RIDGE THRU THE AREA...THOUGH MORE SCATTERED AND THIN. TODAY WILL BE A WARM DAY AND IT WILL BE WINDY. 925 MB WINDS PICK UP TO 35 TO 40 KTS IN THE NRN VALLEY MIDDAY-AFTN. SOUTHERLY FLOW AND CURRENT SFC PATTERN FAVORS HIGHEST WINDS TODAY IN THE NRN VALLEY...CENTERED ON HALLOCK TO WINNIPEG. BASED ON HIGHER WIND SPEEDS GIVEN BY GFS MOS AND LAV MOS GUIDANCE...ISSUED A WIND ADVISORY 17Z-00Z FOR THE NRN RRV. WINDS ELSWHERE LOOK TO HOLD JUST SHY OF ADVISORY LEVELS. SOME CIRRUS AT TIMES TODAY BUT OTHERWISE ONCE THE LOW CLOUDS BURN OFF IN THE FAR EAST....LOTS OF SUN TODAY. WENT WITH A BIT WARMER GUIDANCE WHICH SHOWS 80-84 IN RRV AND ERN ND. WINDS TO HOLD UP TONIGHT AHEAD OF SFC COLD FRONT WHICH WILL ENTER NW ND/SW MANITOBA OVERNIGHT. THE COLD FRONT WILL MOVE EAST AND SOUTHEAST SUNDAY THROUGH THE AREA. MOISTURE IS LIMITED TO ALONG THE INTL BORDER AND INTO CANADA. WILL MAINTAIN CHC POPS MAINLY ALONG AND NORTH OF HWY 2. SOME WEAK CAPE AND SHOWWALTERS AROUND ZERO AND SPC DAY 2 T-STORM OUTLOOK ALL LEAD TO MENTION OF ISOLD THUNDER IN NW MN/NRN RRV SUN AFTN. OVERALL THOUGH A MINOR PRECIP EVENT. .LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY) ISSUED AT 333 AM CDT SAT SEP 26 2015 SIGNIFICANTLY COOLER AIR TO FOLLOW SUNDAY NIGHT INTO MONDAY AS HIGH PRESSURE BUILD SOUTH. CONSENSUS FROM 00Z MODELS IS NOW TO KEEP ALL PRECIP TO OUR SOUTH MONDAY-MONDAY NIGHT AS HIGH SETTLES OVER THE AREA. THUS COORD WITH OTHER OFFICES LED TO REMOVAL OF ANY POPS MON-MON NIGHT. MONDAY NIGHT-EARLY TUESDAY MORNING MAY WELL BRING A FROST TO SOME AREAS AS LOWS IN THE MID 30S MAY WELL BE PRETTY COMMON IN NE ND/NW MN. LEFT OUT FROST WORDING FOR NOW AS SO MANY VARIABLES AT PLAY YET. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 1142 PM CDT FRI SEP 25 2015 NEW TAF SET CONTINUES TO HAVE LIFR CIGS AT KBJI THROUGH 15Z. LATEST HRRR MODEL TRIES TO PUSH CLOUDS OUT OF KBJI BEFORE 15Z...BUT NEW NAM MOS BREAKS IT OUT BETWEEN 15Z AND 18Z. OTHERWISE...WINDS INCREASE WITH GUSTS OVER 30 KTS POSSIBLE AT KTVF AND WEST DURING THE DAY SATURDAY. FOR TUESDAY THROUGH FRIDAY...PROGRESSION OF SEVERAL MID LEVEL RIDGE/TROUGH COUPLETS INDICATED DURING OUR EXTENDED FORECAST PERIOD AS MEAN FLOW REMAINS ESSENTIALLY ZONAL. BEST CHCS FOR PCPN WOULD APPEAR TO BE ON WED AND FRI AS SHORTWVS MEANDER THROUGH. TUESDAY WILL FEATURE CANADIAN HIGH PRESSURE...OFFERING DRY WEATHER WITH LOWS IN THE FROSTY 30S RECOVERING TO AFTN HIGHS CLOSE TO SEASONAL. BY THURS ABV AVG VALUES ONCE AGAIN IN PLACE UNDER SHORTWV RIDGE AS A BROADER UPSTREAM TROUGH LURKS OVER INTERMOUNTAIN REGION POISED TO POUNCE ON NORTHERN PLAINS BY END OF PERIOD/FRI. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...WIND ADVISORY FROM NOON TODAY TO 7 PM CDT THIS EVENING FOR NDZ007-008-016-026-027-029-030-054. MN...WIND ADVISORY FROM NOON TODAY TO 7 PM CDT THIS EVENING FOR MNZ001-004-007. && $$ SHORT TERM...RIDDLE LONG TERM...WJB/RIDDLE AVIATION...KNUTSVIG
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1234 AM CDT SAT SEP 26 2015 .UPDATE... ISSUED AT 1234 AM CDT SAT SEP 26 2015 NO SIGNIFICANT CHANGES FOR THIS EARLY MORNING UPDATE. TIGHT PRESSURE GRADIENT...ESPECIALLY OVER WESTERN NORTH DAKOTA...KEEPING SOUTHERLY WIND SPEEDS AT 10 TO 20 MPH MOST AREAS WITH 20 TO 25 MPH IN THE SOUTHWEST WITH GUSTS TO 25-30 MPH AT MIDNIGHT. THE WINDS WERE KEEPING THE SURFACE LAYER WELL MIXED...WITH VERY MILD CONDITIONS AT MIDNIGHT WITH TEMPERATURES IN THE 60S. EXPECT SURFACE WINDS TO MAINTAIN AT 10 TO 20 MPH MOST AREAS...WITH TEMPERATURES FALLING GRADUALLY. ADJUSTED EXPECTED MINIMUM TEMPERATURES UP A TAD...BUT STILL EXPECT OVERNIGHT LOWS IN THE 50S. AS IN PREVIOUS DISCUSSION...CANNOT RULE OUT SOME LOW STRATUS CLOUDS MOVING NORTHWARD FROM WESTERN NEBRASKA. CONFIDENCE IS LOW AS TO WHETHER THIS WILL OCCUR. THE LATEST SATELLITE LOOPS INDICATE THOSE LOW CLOUDS EXPANDING SOMEWHAT AND MOVING NORTHWARD ACROSS THE NE/SD BORDER. THE NAM MODEL INDICATES SUFFICIENT MOVEMENT NORTHWARD OR FORMATION OF CLOUDS...BUT THE LATEST HRRR ITERATION WOULD SUGGEST ONLY A HINT OF LOW LEVEL MOISTURE MOVING NORTHWARD INTO THE JAMES VALLEY. WILL CONTINUE TO MONITOR CLOSELY REGARDING THE POSSIBILITY FOR MORNING LOW CLOUDS OR FOG FORMATION. UPDATE ISSUED AT 927 PM CDT FRI SEP 25 2015 NO SIGNIFICANT CHANGES FOR THE EVENING UPDATE. SCATTERED CIRRUS CONTINUES TO TRACK WEST TO EAST ACROSS THE FORECAST AREA. LOW CLOUDS FROM WESTERN NEBRASKA INTO SOUTHWEST SOUTH DAKOTA HAVE SHOWN NO PROGRESSION NORTHWARD AS OF YET. STILL CAN NOT RULE OUT SOME LOW STRATUS MAKING IT UP INTO SOUTHWEST/SOUTH CENTRAL ND TOWARD MORNING. BUT AT THIS TIME NOT EXPECTING THE WIDESPREAD FOG/STRATUS WE EXPERIENCED THIS MORNING. WITH WINDS OF 10 TO 20 MPH OVERNIGHT EXPECT MILD LOWS IN THE 50S TO LOWER 60S. UPDATE ISSUED AT 616 PM CDT FRI SEP 25 2015 SURFACE AND UPPER LEVEL HIGH PRESSURE RIDGING EXTENDS FROM THE SOUTHERN AND CENTRAL ROCKIES INTO THE NORTHERN PLAINS IS PROVIDING FOR MOSTLY SUNNY SKIES THIS LATE FRIDAY AFTERNOON. ONLY A FEW HIGH CIRRUS SKIRTING ALONG THE INTERNATIONAL BORDER. A SHORTWAVE TROUGH WELL TO OUR NORTH WITH A SURFACE COLD FRONT INTO NORTHWEST MONTANA WILL APPROACH THE FORECAST AREA TONIGHT BRINGING AN INCREASING SOUTHERLY FLOW ALOFT...WITH A SURFACE FLOW REMAINING AROUND 10 TO 20 MPH. MOISTURE FROM A FILLING UPPER LOW OVER THE CENTRAL PLAINS WILL BE ADVECTED NORTH TONIGHT AND COULD BRING ANOTHER ROUND OF LOW STRATUS INTO WESTERN AND CENTRAL NORTH DAKOTA LATE TONIGHT. OTHERWISE TEMPERATURES WILL REMAIN MILD WITH LOWS MAINLY IN THE 50S. NO SIGNIFICANT CHANGES TO THE LATE AFTERNOON UPDATE OTHER THAN ADJUSTING SKY COVER BASED ON LATEST SATELLITE IMAGERY AND UPDATING LATEST SENSIBLE WEATHER ELEMENTS. && .SHORT TERM...(THIS EVENING THROUGH SATURDAY) ISSUED AT 300 PM CDT FRI SEP 25 2015 MAIN ISSUES FOR THE SHORT TERM WILL BE CLOUDS TONIGHT AND TEMPERATURES FOR SATURDAY. IN SITU MOISTURE FROM A WEAK UPPER LOW MEANDERING ABOUT IN THE CENTRAL PLAINS OF OKLAHOMA AND NEBRASKA WILL GET PULLED NORTH INTO THE NORTHERN PLAINS TONIGHT AS DEPICTED BY THE NAM/GFS. AS THE LOW LEVEL JET INCREASES AFTER SUNSET MORE OF THE MOISTURE WILL MOVE NORTH. ADDED CLOUDS TONIGHT SOUTH CENTRAL SUFFICIENT FOR PARTLY CLOUDY BUT WILL MEED TO MONITOR. ON SATURDAY AN H850 THERMAL RIDGE EXTENDS ACROSS WESTERN NORTH DAKOTA. WILL LIKELY SEE 90 DEGREES SOUTHWEST...AND MID TO UPPER 80S MOST OF WESTERN NORTH DAKOTA AS WELL. THIS CURRENTLY IS BELOW RECORD HIGHS BY ABOUT 3 TO 7 DEGREES BUT WILL BE A WARM LATE SEPTEMBER DAY. KEPT THE FORECAST DRY. .LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY) ISSUED AT 300 PM CDT FRI SEP 25 2015 UPPER LEVEL JET STREAM MIGRATES SLOWLY SOUTHWARD SATURDAY NIGHT INTO EARLY NEXT WEEK AND WILL STEER SEVERAL EMBEDDED MID LEVEL WAVES THROUGH THE LOCAL REGION...GIVING US A CHANCE FOR SHOWERS SAT NIGHT THROUGH MONDAY. THE JET ITSELF WILL PROVIDE UPPER LEVEL DIVERGENCE IN ITS RIGHT ENTRANCE REGION. COOLER TEMPERATURES SUNDAY COMPARED TO SATURDAY...BUT STILL ABOVE SEASONAL NORMALS FOR LATE SEPTEMBER/EARLY OCTOBER IN THE 70S. AS THE UPPER JET EXITS THE REGION...STRONG HIGH PRESSURE MOVES INTO THE NORTHERN PLAINS MONDAY NIGHT BRINGING DRY CONDITIONS AND NEAR NORMAL HIGHS IN THE 60S BOTH MONDAY AND TUESDAY. THERE WILL BE A POTENTIAL FOR WIDESPREAD FROST MONDAY NIGHT...ESPECIALLY NORTH. TEMPERATURE MODERATE WED-FRI WITH RETURN FLOW AT THE SURFACE AND ZONAL FLOW ALOFT. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 1234 AM CDT SAT SEP 26 2015 SOUTH TO SOUTHWEST SURFACE FLOW WILL CONTINUE THROUGH THE FORECAST PERIOD. WITH AN INCREASING SURFACE GRADIENT SOUTHERLY WINDS WILL REMAIN GENERALLY 10 TO 20 MPH...WITH STRONGER SOUTH WINDS OF 15 TO 25 MPH AT KDIK. VERY STRONG SOUTHERLY WINDS ALOFT OVER WESTERN NORTH DAKOTA WITH WINDS NEAR 2000 FT AGL AROUND 40 KNOTS...THUS KEPT THE WIND SHEAR GROUP AT KISN WITH SOUTH WINDS OF AROUND 8-12 KTS AT THE SURFACE EXPECTED THROUGH THE EARLY MORNING HOURS. THE SOUTHERLY WINDS COULD ADVECT LOW LEVEL MOISTURE CURRENTLY OVER THE CENTRAL PLAINS...INTO WESTERN AND CENTRAL NORTH DAKOTA EARLY THIS SATURDAY MORNING. THE THREAT OF WIDESPREAD FOG SEEMS UNLIKELY...BUT A STRATUS CLOUD DECK FORMING IS NOT OUT OF THE QUESTION. FOR NOW HAVE KEPT A SCATTERED LAYER AROUND 1000 FT AT KDIK AND KBIS AROUND 09Z-15Z WITH A TEMPO GROUP WITH LIGHT FOG AND WILL CONTINUE TO MONITOR LATEST TRENDS. SOUTHERLY FLOW BECOMES STRONG SATURDAY AFTERNOON - WITH WINDS OF 15 TO 30 MPH. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...JV SHORT TERM...WAA LONG TERM...NH AVIATION...JV
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1142 PM CDT FRI SEP 25 2015 .UPDATE... ISSUED AT 1142 PM CDT FRI SEP 25 2015 EXPANDED LOW CLOUDS FROM BEMIDJI TO PARK RAPIDS FURTHER WEST INTO CLEARWATER...BECKER...AND OTTER TAIL COUNTIES. EXPECT SOME LIGHT FOG/MIST WITH THE LOWER CLOUDS IN SOME AREAS...WITH THICKER FOG POSSIBLE AS WELL. LOW CLOUDS SHOULD DISSIPATE BY LATE MORNING. UPDATE ISSUED AT 930 PM CDT FRI SEP 25 2015 FRESHENED UP CLOUD COVER A BIT WITH THIS UPDATE...OTHERWISE FORECAST LOOKS ON TRACK. UPDATE ISSUED AT 657 PM CDT FRI SEP 25 2015 UPDATED FORECAST TO INCREASE CLOUD COVER IN THE EAST THROUGH TOMORROW MORNING. LEANED ON SATELLITE TRENDS AND HRRR/NAM MOS DATA FOR SKY CONDITIONS IN THE EAST TONIGHT. ALSO ADDED PATCHY FOG IN THE PARTS OF THE FAR EAST. && .SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT) ISSUED AT 300 PM CDT FRI SEP 25 2015 THE MAIN CHALLENGE WILL BE WINDS...TEMPS AND LOW CHANCES FOR PRECIP. MODELS ARE IN GOOD AGREEMENT...AND PREFER THE GFS THAT SEEMS TO HAVE A GOOD HANDLE ON MOISTURE FIELDS. FOR TONIGHT...SOUTHERLY WINDS SHOULD REMAIN HIGH ENOUGH TO PRECLUDE LOW CLOUD/FOG FORMATION. CAN/T RULE OUT SOME FOG PERHAPS IN THE FAR EAST...FOR NOW HAVE NOT MENTIONED THIS BUT SOMETHING WE WILL MONITOR THIS EVENING. TEMPS SHOULD BE FAIRLY WARM WITH WINDS AND VERY WARM MID LEVEL TEMPS. ON SATURDAY...IT WILL BE WARM AND WINDY WITH HIGHS AROUND 80 OR PERHAPS EVEN INTO THE LOW 80S. THERE WILL BE 40KT TO MIX FROM 850MB FROM THE VALLEY WEST...SO HAVE INCREASED WINDS TO NEAR ADVISORY LEVELS FOR THE VALLEY AND POINTS WEST BY AFTERNOON. FOR SAT NIGHT...IT WILL BE MILD AND DRY AS WE REMAIN IN THE WARM SECTOR. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 300 PM CDT FRI SEP 25 2015 ON SUNDAY...A COLD FRONT WILL MOVE FROM WEST TO EAST THROUGH THE DAY. THERE WILL BE A FAIRLY STRONG CAP IN PLACE...WITH THE BEST CHANCE FOR SHOWERS IN THE NORTH. NOT EXPECTING TOO MUCH OVERALL COVERAGE...BUT SHOWALTERS TO GET SLIGHTLY NEGATIVE SO A FEW RUMBLES CAN/T BE RULED OUT. HAVE JUST MENTIONED SHOWERS FOR NOW THOUGH GIVEN STRONG CAP AND LACK OF DEEPER MOISTURE. FOR MONDAY...IT WILL BE MUCH COOLER WITH THE THREAT OF A FEW SHOWERS MAINLY IN THE SOUTH. FOR MONDAY NIGHT...THE UPPER TROF CONTINUES TO SAG SOUTH ACROSS THE REGION WITH COOLER AND MORE SEASONABLE TEMPERATURES...ALONG WITH A CHANCE FOR LIGHT PCPN. WITH NW FLOW ALOFT...EXPECT A FEW UPPER DISTURBANCES TO MOVE THRU THE FLOW BRINGING MORE CHANCES FOR LIGHT PCPN. SFC HIGH PRESSURE SLIDES ACROSS THE DAKS/MN LATE MON INTO TUE WITH MORE TRANQUIL CONDITIONS...BEFORE SHIFTING E AND RETURN FLOW BRINGS THE START OF A WARMING TREND FOR THE END OF THE PERIOD. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 1142 PM CDT FRI SEP 25 2015 NEW TAF SET CONTINUES TO HAVE LIFR CIGS AT KBJI THROUGH 15Z. LATEST HRRR MODEL TRIES TO PUSH CLOUDS OUT OF KBJI BEFORE 15Z...BUT NEW NAM MOS BREAKS IT OUT BETWEEN 15Z AND 18Z. OTHERWISE...WINDS INCREASE WITH GUSTS OVER 30 KTS POSSIBLE AT KTVF AND WEST DURING THE DAY SATURDAY. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ UPDATE...KNUTSVIG SHORT TERM...DK LONG TERM...HOPKINS/DK AVIATION...KNUTSVIG
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
605 PM EDT SAT SEP 26 2015 .SYNOPSIS... A LARGE AREA OF HIGH PRESSURE OVER NEW ENGLAND WILL MOVE EAST OFF THE COAST ON SUNDAY. MEANWHILE WEAK LOW PRESSURE OFF THE CAROLINA COAST WILL REMAIN NEARLY STATIONARY. THE FLOW BETWEEN THESE TWO SYSTEMS WILL CONTINUE TO FUNNEL ATLANTIC MOISTURE ACROSS THE MID ATLANTIC STATES AND INTO THE OHIO VALLEY THROUGH MONDAY. && .NEAR TERM /THROUGH TONIGHT/... MODELS CONTINUE TO POINT TO INCREASING MID AND LOWER LEVEL MOISTURE FROM THE SOUTH AND SE. THE QUESTION REMAINS HOW MUCH PRECIP SURVIVES THE DOWNSLOPE OFF THE APPALACHIANS. THE HRRR SHOWS NO MEASURABLE PRECIP INTO THE CWA UNTIL AT LEAST 06Z THEN A SURGE OF SCT LIGHT SHRA FOCUSED NNW UP THRU THE CENTRAL PART OF THE CWA TOWARD THE ISLANDS BY DAYBREAK. THE RAP LATEST RUN NOW SHOWS NOTHING MEASURABLE UNTIL ABOUT 12Z. NOT LOOKING FOR MUCH BUT BELIEVE IT DESERVES A MENTION. MAV LOWS WERE A FEW DEGREES TOO LOW LAST NIGHT GIVEN THE CLOUD COVER AND WHILE OUR BIAS GUIDANCE SHOULD BE CATCHING UP HAVE ADDED A DEGREE OR TWO TO LOWS. && .SHORT TERM /SUNDAY THROUGH TUESDAY NIGHT/... GUIDANCE ALL OVER THE PLACE FOR SUNDAY WITH THE NAM SHOWING CATEGORICAL POPS FROM YNG TO ERI DOWN TO LOW CHANCE POPS WEST. MEANWHILE THE MAV IS MORE CONSERVATIVE AND CONSISTENT WITH CHANCE POPS ACROSS THE REGION WITH THE EXCEPTION OF LIKELY AT MNN AND FDY. DIFFERENCES PERSIST INTO SUNDAY NIGHT AND MONDAY AS WELL WITH THE MET WETTER ON BALANCE SUNDAY NIGHT AND THE MAV WETTER MONDAY. THROUGH MONDAY WILL GO WITH THE SREF KEEPING THE BEST CHANCES TO THE EAST HALF OF THE AREA WHERE THE BEST MOISTURE SHOULD BE. FOR NOW WILL KEEP POPS IN THE CHANCE CATEGORY EAST AND CENTRAL COUNTIES AND SLIGHT CHANCE FURTHER WEST. MONDAY NIGHT MOISTURE MOVES EAST SO WILL BACK OFF TO SLIGHT CHANCE. TUESDAY MAIN CONCERN WILL BE THE APPROACHING COLD FRONT FROM THE NORTHWEST AND THE INTERACTION BETWEEN THAT AND THE LEFTOVER MOISTURE. WILL HAVE CHANCE POPS IN PLACE FOR TUESDAY AND ADD THUNDER FOR THE DAY. WILL CONTINUE CHANCE POPS FOR SHOWERS LASTING INTO TUESDAY EVENING...LOWERING POPS AFTER MIDNIGHT. TEMPS CONTINUE FAIRLY MILD. && .LONG TERM /WEDNESDAY THROUGH SATURDAY/... HIGH PRESSURE SHOULD BE BUILDING INTO THE REGION WEDNESDAY MORNING. IT LOOKS RATHER DRY IN THE WAKE OF THE COLD FRONT BUT THE COOLER AIR FLOWING ACROSS LAKE ERIE WILL LIKELY ALLOW SOME CLOUD COVER TO LINGER THROUGH WEDNESDAY MORNING. HIGH PRESSURE SHOULD THEN DOMINATE THE REGION INTO THURSDAY. THE MODELS THEN DIVERGE BEYOND THIS POINT WITH THE ECMWF STILL TRYING TO DIG AN UPPER LOW INTO THE CENTRAL GREAT LAKES. INTERESTING HOW THIS SEEMS TO BOUNCE BETWEEN MODEL RUNS. HAVE CONTINUED TO LEAN CLOSER TO THE GFS FOR NOW. IT WILL BE COOLER THROUGH THE LONG TERM BUT IT WILL NOT BE ALL THAT FAR FROM SEASONAL AVERAGES. && .AVIATION /18Z SATURDAY THROUGH THURSDAY/... VFR CONDITIONS THROUGH TONIGHT. HOWEVER THERE MAY BE SOME LIGHT SPRINKLES OR BRIEF SHOWERS TOWARD SUNRISE FOR THE SOUTHERN AND WESTERN TAF SITES. THIS AREA OF SPRINKLES AND BRIEF SHOWERS WILL THEN DRIFT EASTWARD THROUGH THE AFTERNOON. CONFIDENCE IN THE TIMING OF THE SHOWERS IS LOW AND IF THEY DO OCCUR CONDITIONS WILL SHOULD REMAIN VFR. EASTERLY WINDS WILL BECOME SOUTHEAST LATER TONIGHT AND CONTINUE INTO SUNDAY AFTERNOON. WINDS MAY BE GUSTY AT TIMES THIS INTO THE EVENING HOURS AND THEN AGAIN ACROSS THE EASTERN TAFS SITES ON SUNDAY. GUSTS SHOULD NOT EXCEED 20 KNOTS. OUTLOOK...NON VFR POSSIBLE IN SCATTERED SHOWERS SUNDAY AFTERNOON INTO MONDAY MORNING. NON VFR POSSIBLE IN SHOWERS TUESDAY AFTERNOON/EVENING. && .MARINE... HIGH PRESSURE WILL CONTINUE TO RIDGE BACK INTO THE AREA FROM THE NEW ENGLAND COAST INTO SUNDAY. IT WILL BE DRIFTING EASTWARD AS THE UPPER LEVEL LOW OVER THE CENTRAL APPALACHIANS WEAKENS. THIS SHOULD ALLOW THE PRESSURE GRADIENT TO DECREASE BY SUNDAY NIGHT. EASTERLY WINDS THIS EVENING WILL LIKELY BE IN THE 15 TO 20 KNOT RANGE WITH WAVES BUILDING A BIT AND COULD HOVER CLOSE TO 4 FEET THROUGH 03Z. SO AGAIN IT IS VERY CLOSE TO SMALL CRAFT ADVISORY LEVELS BUT SINCE IT LOOKS TO BE SHORT LIVED WE WILL HOLD OFF ON ANY HEADLINES. WINDS WILL BEGIN TO SHIFT TO TO THE SOUTHEAST AND SOUTH ON SUNDAY WHICH WILL DIRECT THE LARGER WAVES TOWARD THE CANADIAN SHORELINE. WINDS WILL WEAKEN MONDAY INTO MONDAY NIGHT. A COLD FRONT WILL THEN MOVE INTO THE REGION ON TUESDAY WITH INCREASED SOUTHWESTERLY FLOW AHEAD OF IT. NORTHERLY WINDS ARE EXPECTED IN ITS WAKE BUT IT IS NOT ALL THAT COLD. WE WILL HAVE TO MONITOR FOR SOME LARGER WAVES FROM THE LONGER FETCH OF THE WIND BUT AT THIS POINT WIND SPEEDS DO NOT LOOK TO BE MUCH OVER 15 KNOTS. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...NONE. PA...NONE. MARINE...NONE. && $$ SYNOPSIS...TK NEAR TERM...TK/ADAMS SHORT TERM...TK LONG TERM...MULLEN AVIATION...MULLEN MARINE...MULLEN
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
305 PM EDT SAT SEP 26 2015 .SYNOPSIS... A LARGE AREA OF HIGH PRESSURE OVER NEW ENGLAND WILL MOVE EAST OFF THE COAST ON SUNDAY. MEANWHILE WEAK LOW PRESSURE OFF THE CAROLINA COAST WILL REMAIN NEARLY STATIONARY. THE FLOW BETWEEN THESE TWO SYSTEMS WILL CONTINUE TO FUNNEL ATLANTIC MOISTURE ACROSS THE MID ATLANTIC STATES AND INTO THE OHIO VALLEY THROUGH MONDAY. && .NEAR TERM /THROUGH TONIGHT/... FOR THIS EVENING AND THE OVERNIGHT...MODELS CONTINUE TO POINT TO INCREASING MOISTURE FROM THE SOUTH. THE QUESTION REMAINS HOW MUCH PRECIP SURVIVES THE DOWNSLOPE OFF THE APPALACHIANS. AT THIS TIME THERE IS AT LEAST A FEW SHOWERS IN SRN OHIO AND ERN KY THAT APPEAR TO BE REACHING THE GROUND BUT FOR THE MOST PART IT IS DRY. THE HRRR ALSO SHOWS DRY CONDITIONS LASTING THROUGH THE EVENING BEFORE ANY SHOWERS REACH THE SOUTHERN TIER OF COUNTIES. WILL BEGIN THE EVENING DRY AND THEN BRING IN THE SLIGHT CHANCE TO THE SOUTH MID EVENING. OVERNIGHT WILL HAVE POPS INCREASE TO LOW CHANCE FROM THE SOUTHEAST ACROSS THE CENTRAL HIGHLANDS TO THE CENTRAL LAKESHORE. NOT LOOKING FOR MUCH BUT BELIEVE IT DESERVES A MENTION. MAV LOWS WERE A FEW DEGREES TOO LOW LAST NIGHT GIVEN THE CLOUD COVER AND WHILE OUR BIAS GUIDANCE SHOULD BE CATCHING UP WILL ADD A DEGREE OR TWO TO LOWS. && .SHORT TERM /SUNDAY THROUGH TUESDAY NIGHT/... GUIDANCE ALL OVER THE PLACE FOR SUNDAY WITH THE NAM SHOWING CATEGORICAL POPS FROM YNG TO ERI DOWN TO LOW CHANCE POPS WEST. MEANWHILE THE MAV IS MORE CONSERVATIVE AND CONSISTENT WITH CHANCE POPS ACROSS THE REGION WITH THE EXCEPTION OF LIKELY AT MNN AND FDY. DIFFERENCES PERSIST INTO SUNDAY NIGHT AND MONDAY AS WELL WITH THE MET WETTER ON BALANCE SUNDAY NIGHT AND THE MAV WETTER MONDAY. THROUGH MONDAY WILL GO WITH THE SREF KEEPING THE BEST CHANCES TO THE EAST HALF OF THE AREA WHERE THE BEST MOISTURE SHOULD BE. FOR NOW WILL KEEP POPS IN THE CHANCE CATEGORY EAST AND CENTRAL COUNTIES AND SLIGHT CHANCE FURTHER WEST. MONDAY NIGHT MOISTURE MOVES EAST SO WILL BACK OFF TO SLIGHT CHANCE. TUESDAY MAIN CONCERN WILL BE THE APPROACHING COLD FRONT FROM THE NORTHWEST AND THE INTERACTION BETWEEN THAT AND THE LEFTOVER MOISTURE. WILL HAVE CHANCE POPS IN PLACE FOR TUESDAY AND ADD THUNDER FOR THE DAY. WILL CONTINUE CHANCE POPS FOR SHOWERS LASTING INTO TUESDAY EVENING...LOWERING POPS AFTER MIDNIGHT. TEMPS CONTINUE FAIRLY MILD. && .LONG TERM /WEDNESDAY THROUGH SATURDAY/... HIGH PRESSURE SHOULD BE BUILDING INTO THE REGION WEDNESDAY MORNING. IT LOOKS RATHER DRY IN THE WAKE OF THE COLD FRONT BUT THE COOLER AIR FLOWING ACROSS LAKE ERIE WILL LIKELY ALLOW SOME CLOUD COVER TO LINGER THROUGH WEDNESDAY MORNING. HIGH PRESSURE SHOULD THEN DOMINATE THE REGION INTO THURSDAY. THE MODELS THEN DIVERGE BEYOND THIS POINT WITH THE ECMWF STILL TRYING TO DIG AN UPPER LOW INTO THE CENTRAL GREAT LAKES. INTERESTING HOW THIS SEEMS TO BOUNCE BETWEEN MODEL RUNS. HAVE CONTINUED TO LEAN CLOSER TO THE GFS FOR NOW. IT WILL BE COOLER THROUGH THE LONG TERM BUT IT WILL NOT BE ALL THAT FAR FROM SEASONAL AVERAGES. && .AVIATION /18Z SATURDAY THROUGH THURSDAY/... VFR CONDITIONS THROUGH TONIGHT. HOWEVER THERE MAY BE SOME LIGHT SPRINKLES OR BRIEF SHOWERS TOWARD SUNRISE FOR THE SOUTHERN AND WESTERN TAF SITES. THIS AREA OF SPRINKLES AND BRIEF SHOWERS WILL THEN DRIFT EASTWARD THROUGH THE AFTERNOON. CONFIDENCE IN THE TIMING OF THE SHOWERS IS LOW AND IF THEY DO OCCUR CONDITIONS WILL SHOULD REMAIN VFR. EASTERLY WINDS WILL BECOME SOUTHEAST LATER TONIGHT AND CONTINUE INTO SUNDAY AFTERNOON. WINDS MAY BE GUSTY AT TIMES THIS INTO THE EVENING HOURS AND THEN AGAIN ACROSS THE EASTERN TAFS SITES ON SUNDAY. GUSTS SHOULD NOT EXCEED 20 KNOTS. OUTLOOK...NON VFR POSSIBLE IN SCATTERED SHOWERS SUNDAY AFTERNOON INTO MONDAY MORNING. NON VFR POSSIBLE IN SHOWERS TUESDAY AFTERNOON/EVENING. && .MARINE... HIGH PRESSURE WILL CONTINUE TO RIDGE BACK INTO THE AREA FROM THE NEW ENGLAND COAST INTO SUNDAY. IT WILL BE DRIFTING EASTWARD AS THE UPPER LEVEL LOW OVER THE CENTRAL APPALACHIANS WEAKENS. THIS SHOULD ALLOW THE PRESSURE GRADIENT TO DECREASE BY SUNDAY NIGHT. EASTERLY WINDS THIS EVENING WILL LIKELY BE IN THE 15 TO 20 KNOT RANGE WITH WAVES BUILDING A BIT AND COULD HOVER CLOSE TO 4 FEET THROUGH 03Z. SO AGAIN IT IS VERY CLOSE TO SMALL CRAFT ADVISORY LEVELS BUT SINCE IT LOOKS TO BE SHORT LIVED WE WILL HOLD OFF ON ANY HEADLINES. WINDS WILL BEGIN TO SHIFT TO TO THE SOUTHEAST AND SOUTH ON SUNDAY WHICH WILL DIRECT THE LARGER WAVES TOWARD THE CANADIAN SHORELINE. WINDS WILL WEAKEN MONDAY INTO MONDAY NIGHT. A COLD FRONT WILL THEN MOVE INTO THE REGION ON TUESDAY WITH INCREASED SOUTHWESTERLY FLOW AHEAD OF IT. NORTHERLY WINDS ARE EXPECTED IN ITS WAKE BUT IT IS NOT ALL THAT COLD. WE WILL HAVE TO MONITOR FOR SOME LARGER WAVES FROM THE LONGER FETCH OF THE WIND BUT AT THIS POINT WIND SPEEDS DO NOT LOOK TO BE MUCH OVER 15 KNOTS. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...NONE. PA...NONE. MARINE...NONE. && $$ SYNOPSIS...TK NEAR TERM...TK SHORT TERM...TK LONG TERM...MULLEN AVIATION...MULLEN MARINE...MULLEN
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1152 PM EDT SUN SEP 27 2015 .SYNOPSIS... HIGH PRESSURE IS OFF THE COAST AND WINDS ARE MORE-SOUTHERLY. A COLD FRONT WILL PUSH SOUTH ACROSS PENNSYLVANIA LATE TUESDAY...THEN STALL OUT SOUTH OF THE STATE. A SLOW MOVING COASTAL LOW WILL AFFECT PORTIONS OF THE MID ATLANTIC REGION LATE IN THE WEEK. COOLER TEMPERATURES WILL PREVAIL FOR THE SECOND PART OF THE WEEK. && .NEAR TERM /UNTIL 7 AM MONDAY MORNING/... 1015 PM UPDATE... AS EXPECTED...THE NRN TIER IS HAVING A GREAT EVENING WITH RESPECT TO BEING ABLE TO SEE THE ECLIPSE. HOWEVER...CLOUDS ROLLED INTO STATE COLLEGE JUST IN TIME TO BLOCK OUT A REALLY GOOD VIEW. JUST A PASSING BREAK IN THE CLOUDS HERE AND THERE. THE CLOUDS SHOULD CONTINUE TO GRADUALLY THICKEN/LOWER/ADVANCE NORTHWARD. HAVE INCREASED POPS IN THE NWRN COS SINCE THE HRRR AND CURRENT RADAR TRENDS POINT TO A BLOSSOMING AREA OF SHOWERS OVER WRN PA SLIDING UP INTO THEM FROM THE SSW. TEMPS ARE RIGHT ON TRACK. 645 PM UPDATE... MOST OF THE CLOUDS HAVE BRIEFLY DISSIPATED OVER THE NRN HALF OF THE AREA. HOWEVER...THE MORE-CONTINUOUS AND LOW-BASED CLOUD COVER IS SPREADING IT/S WAY NORTHWARD INTO CENTRAL PA. THESE CLOUDS SHOULD CONTINUE TO SPREAD NORTHWARD THROUGH THE NEXT FEW HOURS...AND MAY MAKE THE VIEWING OF THE ECLIPSE DIFFICULT FOR MOST OF THE AREA. IT IS ALMOST A CERTAINTY THAT THE SRN HALF OF THE AREA WILL BE MOSTLY TO ENTIRELY CLOUDY AND ONLY A FEW CRACKS IN THE CLOUDS WILL APPEAR TO CATCH A BRIEF GLIMPSE OF THE MOON/ECLIPSE. RIGHT ALONG THE NY BORDER STILL LOOKING LIKE THE PART OF CENTRAL PA WHICH COULD HAVE A DECENT VIEW OF THE ECLIPSE. BUT THE CLOUDS ARE EXPANDING...ESPECIALLY THE LOWER DECKS AROUND 3KFT. WHILE THE HIGHER CLOUDS AT OR ABOVE 12KFT MAY BE THIN ENOUGH TO SEE THROUGH AT TIMES...THE LOWER CLOUDS ARE MORE OPAQUE. A FEW SPRINKLES ALONG THE MD BORDER ARE ALSO POSSIBLE THIS EVENING. ON THE WHOLE...JUST MINOR TWEAKS TO THE SKY FCST. PREV... LATEST MESOSCALE MODELS IN GOOD AGREEMENT WITH LATEST RADAR TRENDS IN REDUCING ISOLATED SHOWERS ACROSS THE SOUTHERN THIRD OF CENTRAL PA THIS AFTERNOON INTO THIS EVENING...AS UPPER TROF LIFTS NORTHWARD THIS AFTERNOON AND INTO NY STATE. ADDITIONAL ISOLATED ACTIVITY ACROSS WV AND VA LIFTING NORTHWARD IN THE ANOMALOUS ESE FLOW WILL KEEP AT LEAST ISOLATED COVERAGE OF SHOWERS GOING. HRRR NOW SHOWS COVERAGE OF SHOWERS WELL SOUTHWEST OF MY CWA THIS EVENING OVER WV AND VA. BEST CHC OF SHOWERS REMAINS ACROSS THE SOUTH CENTRAL MOUNTAINS INTO THIS EVENING. DESPITE THICKENING AND LOWERING CLOUDS...LATEST GUIDANCE CONTINUES TO SUPPORT A MAINLY DRY FCST ACROSS THE EASTERN HALF OF THE STATE...WHERE SFC RIDGE AND LOW PWAT AIR MASS WILL LIE. LINGERING FETCH INTO THE ALLEGHENY PLATEAU WILL KEEP A BIT OF SHOWER ACTIVITY THERE...BUT IT WILL BE LIGHT. WIDESPREAD CLOUDS WILL KEEP THINGS MILDER NIGHT THAN LAST NIGHT WITH MINS WITH MINS IN THE MID TO UPPER 50S. && .SHORT TERM /7 AM MONDAY MORNING THROUGH 6 PM MONDAY/... OFFSHORE HIGH RETREATS FARTHER OFFSHORE ON MONDAY...WITH EASTERLY FETCH DECREASING AS A RESULT. DEEP LAYER MOISTURE PLUME INCREASES OVER PA AS A RESULT OF THE AMPLIFIED SOUTHERLY FLOW ALOFT. FORCING REMAINS WEAK ON MONDAY...BUT THE SERLY LOW LVL FLOW AND ASSOC OROGRAPHIC FORCING WILL KEEP THINGS CLOUDY FOR MOST. WEAK UPPER TROF APPROACHES IN THE AFTERNOON TO PRODUCE ISOLD TO SCT SHOWERS...ESP ACROSS THE WEST. HIGHS WILL RANGE FROM THE MID TO UPPER 60S NORTH TO THE MID TO UPPER 60S SOUTHEAST. && .LONG TERM /MONDAY NIGHT THROUGH SUNDAY/... MID SHIFT DID EDGE POPS UP SOME FOR THE LATER PART OF THE WEEK. THUS DID NOT MAKE ANY LARGE CHANGES TO THIS PART OF THE FCST. MAIN CHANGE WAS TO EDGE POPS DOWN JUST A LITTLE ON THE WESTERN AND NORTHERN EDGES. FIRST PROBLEM IS THE COLD FRONT FOR LATE TUE. DID UP POPS TO LIKELY. AS NOTED YESTERDAY...KEY TO FCST THE RATHER DRY AIR BEING ADVECTED INTO THE AREA THE LAST FEW DAYS. ANYWAY...NOT SOLD ON A LOT OF RAIN. MODELS HINT AT SOME MODERATE QPF. WILL HAVE TO ADVECT HIGHER DEWPOINT/PW AIR IN FROM THE SE COAST TO GET MUCH RAIN. LEFT THUNDER OUT FOR NOW. LATER WED AND THU STILL LOOK MAINLY DRY. FOR FRIDAY AND SAT...MODELS SHOW A LOW BACKING IN FROM THE COAST...AND A STRONG EASTERLY FLOW BETWEEN A LARGE HIGH OVER EASTERN CANADA AND THE LOW TO THE SOUTH. LOOKS LIKE THE MODELS TRY TO PHASE THE LONGWAVE ENERGY WITH A WARM CORE LOW. A LOT OF SPREAD IN SOLUTIONS FROM DAY TO DAY. LOOKS LIKE THE TIMING WOULD TAKE THE BULK OF THE RAIN TO THE NE BY LATER SAT. FOR NOW...LEFT SUNDAY DRY. NOT LOOKING AT FROST AT THIS POINT...BUT SOME RATHER COLD AIR WELL NORTH OF PA WITH SFC HIGH. ALTHOUGH MUCH UNCERTAINTY REMAINS WITH REGARDS TO LATE WEEK RAIN...THERE IS A GOOD DEAL OF CONFIDENCE IN TEMPS TAKING TUMBLE AFTER A VERY MILD MON-TUE. NORTHERLY FLOW/LOW LVL CAA IN WAKE OF COLD FRONT...COMBINED WITH POSSIBLE RAIN...SHOULD TRANSLATE TO TEMPS AOB CLIMO LATE NEXT WEEK...ESP DURING THE DAYTIME. && .AVIATION /04Z MONDAY THROUGH FRIDAY/... LLVL MOISTURE WILL SLOWLY INCREASE OVERNIGHT...THROUGH THE DAY MONDAY AS THE FLOWS GRADUALLY VEERS FROM FROM EASTERLY TO SOUTHERLY WITHIN ABOUT THE LOWEST 5 KFT AGL. THIS WILL MAINTAIN LAYERS OF DRY AIR ABOVE THE OTHERWISE EXPANDING/LOWERING DECK OF STRATO CU AND STRATUS. THE CURRENT MAINLY MVFR STRATO CU/STRATUS DECK EXTENDING FROM KBFD TO KUNV AND KAOO HAS LOWERED TO IFR ACROSS THE LAUREL HIGHLANDS. THE CLOUDS WILL CONTINUE TO GRADUALLY LOWER FROM SW TO NE OVERNIGHT WITH ISOLATED TO SCATTERED -SHRA AFFECTING PRIMARILY THE SWRN THIRD-HALF OF PENN. AREAS OF IFR CIGS /WITH SOME DRIZZLE OR SCATTERED -SHRA/ WILL OCCUR ACROSS THE CENTRAL AND WRN MTNS OF PENN LATE TONIGHT AND MONDAY MORNING...ESPECIALLY INVOF KJST WHERE THE SERLY LLVL UPSLOPE FLOW IS MAXIMIZED. SURFACE WINDS WILL BE FROM THE EAST TO SOUTHEAST AT SPEEDS OF GENERALLY 5-10MPH. LOW CIGS PERSIST INTO MON...WITH BEST CHANCE FOR IMPROVEMENT BEING OVER THE LOWER SUSQ. CONDITIONS COULD STAY IN THE LOW MVFR /OR EVEN UPPER IFR/ RANGE FOR MUCH OF THE DAY ACROSS NW HALF OF OUR FCST AREA WITH LIGHT RAIN SHOWERS AROUND. OUTLOOK... MON...INCREASING LIKELIHOOD OF LIGHT RAIN/LOW CIGS...FOCUSED MAINLY ACROSS WESTERN MTNS OF PENN. TUE...LOW CIGS/SHOWERS LIKELY...ESP NW HALF. TUE NIGHT...LOW CIGS/SCT SHOWERS. WED...LOW CIGS NW MTNS EARLY. CHC SHOWERS SOUTH. THU...NO SIG WX. FRI...CHC OF SHOWERS. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...DEVOIR/MARTIN NEAR TERM...DANGELO/DEVOIR SHORT TERM...DEVOIR LONG TERM...FITZGERALD/MARTIN AVIATION...LAMBERT/MARTIN
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NWS RAPID CITY SD
1058 AM MDT SAT SEP 26 2015 .SHORT TERM...TODAY THROUGH SUNDAY NIGHT ISSUED AT 245 AM MDT SAT SEP 26 2015 LONG WAVE RIDGE AXIS WILL REMAIN OVER THE NORTHERN PLAINS TODAY AND WILL BEGIN TO SHIFT EAST TONIGHT INTO SUN AS A DEEP WESTERN NOAM TROUGH SHIFTS EAST ACROSS SOUTHERN CANADA. LEE SIDE TROUGH AND ASSOCIATED SFC LOW WILL PUSH EAST TONIGHT WITH THIS SYSTEM...SUPPORTING A COLD FRONT INTO THE REGION SUNDAY...ALTHOUGH THE BULK OF CAA WILL REMAIN NORTH OF THE FA. NORTHERN STEAM TROUGH AND ITS SOUTHERN PERIPHERY IMPULSE MAY SUPPORT ENOUGH LIFT FOR A FEW SHRA SUNDAY NIGHT...OTHERWISE...DRY WX WILL CONTINUE ACROSS THE REGION. TODAY...MORNING FOG AND LOW CLOUDS CAN BE EXPECTED ACROSS THE SOUTHERN ZONES AS PERSISTENT SOUTHERLY FLOW ADVECTS LL MOISTURE NORTH ACROSS THE PLAINS. MOSTLY SUNNY SKIES EXPECTED BY AFTERNOON ALL PLACES WITH GUSTY SOUTHERLY WINDS ON THE SD PLAINS. EXPECTED SOUTHERN WINDS OF 15 TO 25 MPH WITH GUSTS TO AROUND 35 AT TIMES...ESP OVER CENTRAL SD. WARMER DAY FORECAST ALL PLACES...WARMEST ON THE WY PLAINS WHERE PROXIMITY TO THE THERMAL RIDGE AND DEEP MIXING ARE EXPECTED TO SUPPORT 90S. TONIGHT...SFC TROUGH WILL SHIFT EAST WITH SUSTAINED SOUTHERLY FLOW EXPECTED GIVEN ONGOING PRESSURE FALLS. DOWNSLOPING AND RESULTANT DOWNWARD TRANSPORT WILL SUPPORT WARM CONDS IN THE LEE OF THE BLACK HILLS...ESP THE EASTERN FOOTHILLS. SUNDAY...SFC TROUGH/COLD FRONT WILL SHIFT SE SUNDAY WITH COOLER CONDS EXPECTED ALL BUT SCENTRAL SD WHERE TIMING OF THE THE FRONT WILL SUPPORT WARMER HIGHS THAN SAT. LINGERING LL MOISTURE/DIURNAL HEATING AND DEVELOPING SOUTHERN HILLS EDDY CONVERGENCE MAY SUPPORT AN AFTERNOON SHOWER/TS OVER THE SOUTHERN/CENTRAL BLACK HILLS...BUT GIVEN WEAK INSTABILITY PROGS AND LACK OF MODEL SUPPORT...HAVE LEFT SUNDAY AFTERNOON DRY THERE. A LITTLE BETTER CHANCES FOR SHRA ARE EXPECTED SUNDAY NIGHT AS THE BULK OF LSA AND FGEN ARRIVE...COUPLED WITH THE RR ENTRANCE REGION OF AN UPPER JET STREAK. HAVE BUMPED POPS UP A BIT IN LINE WITH MODEL TRENDS. MUCH COOLER TEMPS EXPECTED SUN NIGHT...ESP WHERE RAIN AND RESULTANT WETBULBING OCCURS. .LONG TERM...MONDAY THROUGH FRIDAY ISSUED AT 245 AM MDT SAT SEP 26 2015 WRLY UPPER FLOW WILL DEVELOP EARLY NEXT WEEK ACROSS THE NORTHERN PLAINS. SEVERAL WEAK SHORT-WAVES ARE PROGGED TO CROSS THE REGION BRINGING CHANCES FOR SHOWERS AND THUNDERSTORMS TO THE AREA. THE BEST CHANCES AT THIS POINT APPEAR TO BE MONDAY NIGHT INTO TUESDAY ALTHOUGH THE GFS/ECM ARE STILL TRYING TO FIGURE OUT THE TRACK AND TIMING OF WAVES. MODELS ARE NOW SHOWING A POTENTIALLY STRONG SHORTWAVE TROUGH CROSSING THE NRN PLAINS LATER IN THE WORK WEEK. DROPPED MAX TEMPS QUITE A BIT MONDAY AS IT NOW LOOKS LIKE DECENT COLD AIR ADVECTION MOVING INTO THE REGION EARLY MONDAY. A WARMING TREND IS THEN EXPECTED TOWARD MIDWEEK AS RETURN FLOW SETS UP. SLIGHTLY COOLER AND MORE SEASONABLE TEMPS POSSIBLE LATER IN THE WORK WEEK AS CHANCES OF PRECIP INCREASE AGAIN. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY) ISSUED AT 1056 AM MDT SAT SEP 26 2015 VFR CONDITIONS ARE EXPECTED THROUGH 18Z SUNDAY. GUSTY SOUTH WINDS WILL PERSIST ACROSS THE WRN/CNTRL SD PLAINS THROUGH THIS EVENING...WITH A COLD FRONT ENTERING NERN WY/NWRN SD AROUND 06Z. THIS FRONT WILL BRING GUSTY NORTHWEST WINDS FOR THE WRN SD PLAINS ON SUNDAY. && .UNR WATCHES/WARNINGS/ADVISORIES... SD...NONE. WY...NONE. && $$ SHORT TERM...JC LONG TERM...13 AVIATION...BUNKERS
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NWS RAPID CITY SD
248 AM MDT SAT SEP 26 2015 .SHORT TERM...TODAY THROUGH SUNDAY NIGHT ISSUED AT 245 AM MDT SAT SEP 26 2015 LONG WAVE RIDGE AXIS WILL REMAIN OVER THE NORTHERN PLAINS TODAY AND WILL BEGIN TO SHIFT EAST TONIGHT INTO SUN AS A DEEP WESTERN NOAM TROUGH SHIFTS EAST ACROSS SOUTHERN CANADA. LEE SIDE TROUGH AND ASSOCIATED SFC LOW WILL PUSH EAST TONIGHT WITH THIS SYSTEM...SUPPORTING A COLD FRONT INTO THE REGION SUNDAY...ALTHOUGH THE BULK OF CAA WILL REMAIN NORTH OF THE FA. NORTHERN STEAM TROUGH AND ITS SOUTHERN PERIPHERY IMPULSE MAY SUPPORT ENOUGH LIFT FOR A FEW SHRA SUNDAY NIGHT...OTHERWISE...DRY WX WILL CONTINUE ACROSS THE REGION. TODAY...MORNING FOG AND LOW CLOUDS CAN BE EXPECTED ACROSS THE SOUTHERN ZONES AS PERSISTENT SOUTHERLY FLOW ADVECTS LL MOISTURE NORTH ACROSS THE PLAINS. MOSTLY SUNNY SKIES EXPECTED BY AFTERNOON ALL PLACES WITH GUSTY SOUTHERLY WINDS ON THE SD PLAINS. EXPECTED SOUTHERN WINDS OF 15 TO 25 MPH WITH GUSTS TO AROUND 35 AT TIMES...ESP OVER CENTRAL SD. WARMER DAY FORECAST ALL PLACES...WARMEST ON THE WY PLAINS WHERE PROXIMITY TO THE THERMAL RIDGE AND DEEP MIXING ARE EXPECTED TO SUPPORT 90S. TONIGHT...SFC TROUGH WILL SHIFT EAST WITH SUSTAINED SOUTHERLY FLOW EXPECTED GIVEN ONGOING PRESSURE FALLS. DOWNSLOPING AND RESULTANT DOWNWARD TRANSPORT WILL SUPPORT WARM CONDS IN THE LEE OF THE BLACK HILLS...ESP THE EASTERN FOOTHILLS. SUNDAY...SFC TROUGH/COLD FRONT WILL SHIFT SE SUNDAY WITH COOLER CONDS EXPECTED ALL BUT SCENTRAL SD WHERE TIMING OF THE THE FRONT WILL SUPPORT WARMER HIGHS THAN SAT. LINGERING LL MOISTURE/DIURNAL HEATING AND DEVELOPING SOUTHERN HILLS EDDY CONVERGENCE MAY SUPPORT AN AFTERNOON SHOWER/TS OVER THE SOUTHERN/CENTRAL BLACK HILLS...BUT GIVEN WEAK INSTABILITY PROGS AND LACK OF MODEL SUPPORT...HAVE LEFT SUNDAY AFTERNOON DRY THERE. A LITTLE BETTER CHANCES FOR SHRA ARE EXPECTED SUNDAY NIGHT AS THE BULK OF LSA AND FGEN ARRIVE...COUPLED WITH THE RR ENTRANCE REGION OF AN UPPER JET STREAK. HAVE BUMPED POPS UP A BIT IN LINE WITH MODEL TRENDS. MUCH COOLER TEMPS EXPECTED SUN NIGHT...ESP WHERE RAIN AND RESULTANT WETBULBING OCCURS. .LONG TERM...MONDAY THROUGH FRIDAY ISSUED AT 245 AM MDT SAT SEP 26 2015 WRLY UPPER FLOW WILL DEVELOP EARLY NEXT WEEK ACROSS THE NORTHERN PLAINS. SEVERAL WEAK SHORT-WAVES ARE PROGGED TO CROSS THE REGION BRINGING CHANCES FOR SHOWERS AND THUNDERSTORMS TO THE AREA. THE BEST CHANCES AT THIS POINT APPEAR TO BE MONDAY NIGHT INTO TUESDAY ALTHOUGH THE GFS/ECM ARE STILL TRYING TO FIGURE OUT THE TRACK AND TIMING OF WAVES. MODELS ARE NOW SHOWING A POTENTIALLY STRONG SHORTWAVE TROUGH CROSSING THE NRN PLAINS LATER IN THE WORK WEEK. DROPPED MAX TEMPS QUITE A BIT MONDAY AS IT NOW LOOKS LIKE DECENT COLD AIR ADVECTION MOVING INTO THE REGION EARLY MONDAY. A WARMING TREND IS THEN EXPECTED TOWARD MIDWEEK AS RETURN FLOW SETS UP. SLIGHTLY COOLER AND MORE SEASONABLE TEMPS POSSIBLE LATER IN THE WORK WEEK AS CHANCES OF PRECIP INCREASE AGAIN. && .AVIATION...FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING ISSUED AT 245 AM MDT SAT SEP 26 2015 MVFR/IFR CIGS AND VSBY EXPECTED ACROSS PORTIONS OF THE WRN SD PLAINS BEFORE DISSIPATING BY MID MORNING. OTHERWISE VFR CONDITIONS ARE EXPECTED TODAY AND TONIGHT. && .UNR WATCHES/WARNINGS/ADVISORIES... SD...NONE. WY...NONE. && $$ SHORT TERM...JC LONG TERM...13 AVIATION...13
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
933 PM CDT SUN SEP 27 2015 .UPDATE... MAIN UPDATE TO THE FORECAST THIS EVENING WAS TO SLOW THE ONSET OF SHOWERS/LIGHT RAINFALL. THE CLOUD SHIELD ASSOCIATED WITH THE BROAD GULF LOW PRESSURE SYSTEM IS SPREADING NORTH BUT THE RAINFALL ASSOCIATED WITH IT HAS BEEN RELEGATED WELL SOUTH THUS FAR. TIME- HEIGHTS SUGGEST PRECIP WILL NOT REACH AREAS ALONG I-40 UNTIL LATE MONDAY MORNING...THEREFORE UPDATED THE FORECAST TO REFLECT THIS. OTHERWISE...TEMPERATURE TRENDS AND THE REST OF THE FORECAST REMAINS ON TRACK. TVT && .PREV DISCUSSION... /ISSUED 649 PM CDT SUN SEP 27 2015/ UPDATE... UPDATED FOR 00Z AVIATION DISCUSSION BELOW. PREV DISCUSSION... /ISSUED 336 PM CDT SUN SEP 27 2015/ DISCUSSION...WATER VAPOR SATELLITE TRENDS THIS AFTERNOON PLACE AN UPPER LEVEL LOW CENTERED JUST OFF THE TEXAS GULF COAST NEAR CORPUS CHRISTI TEXAS. A SHORTWAVE TROUGH ROTATING AROUND THIS UPPER LEVEL LOW IS PRODUCING SHOWERS AND THUNDERSTORMS ACROSS PORTIONS OF SOUTHERN MISSISSIPPI THIS AFTERNOON AND A FEW ISOLATED/SCATTERED RAIN SHOWERS BEGINNING TO APPROACH PORTIONS OF NORTHEAST MISSISSIPPI SOUTH OF TUPELO LATE THIS AFTERNOON. AS OF 3 PM CDT...TEMPERATURES ACROSS THE MID SOUTH ARE IN THE UPPER 70S TO LOWER 80S AT MOST LOCATIONS. SHORT TERM MODEL TRENDS INDICATE THE UPPER LEVEL LOW OFF THE TEXAS GULF COAST WILL REMAIN NEARLY STATIONARY FOR THE NEXT 24 HOURS. SEVERAL SHORTWAVE TROUGHS ROTATING AROUND THIS UPPER LEVEL LOW WILL BRING INCREASING CHANCES FOR SHOWERS AND THUNDERSTORMS TO THE MID SOUTH. BEST CHANCES FOR SHOWERS AND THUNDERSTORMS STILL APPEARS TO BE MONDAY NIGHT INTO TUESDAY AS THE UPPER LEVEL LOW WEAKENS AND BECOMES ABSORBED INTO AN UPPER LEVEL TROUGH AXIS AND SHIFTS EAST TOWARDS THE TENNESSEE VALLEY BY WEDNESDAY. THIS WILL ALSO RESULT IN RAIN CHANCES GRADUALLY SHIFTING EAST ON WEDNESDAY. COOLER TEMPERATURES ARE EXPECTED FOR THE REMAINDER OF THE WEEK WITH THE EASTERN UNITED STATES BEING UNDER THE INFLUENCE OF THE UPPER LEVEL TROUGH. LONG TERM RUN TO RUN CONTINUITY ISSUES PERSIST FOR NEXT WEEKEND AS GFS/ECMWF MODELS DIFFER WITH RESPECT TO DEPTH OF THE EASTERN UNITED STATES TROUGH AXIS AND THE POTENTIAL FOR ANY PRECIPITATION ASSOCIATED WITH SHORTWAVES MOVING ALONG THE PERIPHERY OF THE UPPER LEVEL TROUGH AXIS. THUS...WILL GO WITH A PRECIPITATION FREE FORECAST FOR THE LONG TERM UNTIL MODELS COME INTO BETTER AGREEMENT. CJC .AVIATION... 00Z TAFS LOW/MID LEVEL MOISTURE WILL FLOW NORTH INTO THE MIDSOUTH TONIGHT...AHEAD OF AN UPPER LOW CENTERED OVER THE SOUTHEAST TX COAST. MVFR CHANCES WILL INCREASE FIRST AT TUP THIS EVENING...AND MEM/MKL/JBR DURING THE OVERNIGHT. LATEST NAM AND HRRR GUIDANCE SUGGESTED DELAYING THE ONSET OF SHRA AND MVFR FROM EARLIER SOLUTIONS AND 00Z TAFS REFLECT THIS. PWB && .MEG WATCHES/WARNINGS/ADVISORIES... AR...NONE. MO...NONE. MS...NONE. TN...NONE. && $$
AREA FORECAST DISCUSSION...UPDATED
NWS MEMPHIS TN
649 PM CDT SUN SEP 27 2015 .UPDATE... UPDATED FOR 00Z AVIATION DISCUSSION BELOW. && .PREV DISCUSSION... /ISSUED 336 PM CDT SUN SEP 27 2015/ DISCUSSION...WATER VAPOR SATELLITE TRENDS THIS AFTERNOON PLACE AN UPPER LEVEL LOW CENTERED JUST OFF THE TEXAS GULF COAST NEAR CORPUS CHRISTI TEXAS. A SHORTWAVE TROUGH ROTATING AROUND THIS UPPER LEVEL LOW IS PRODUCING SHOWERS AND THUNDERSTORMS ACROSS PORTIONS OF SOUTHERN MISSISSIPPI THIS AFTERNOON AND A FEW ISOLATED/SCATTERED RAIN SHOWERS BEGINNING TO APPROACH PORTIONS OF NORTHEAST MISSISSIPPI SOUTH OF TUPELO LATE THIS AFTERNOON. AS OF 3 PM CDT...TEMPERATURES ACROSS THE MID SOUTH ARE IN THE UPPER 70S TO LOWER 80S AT MOST LOCATIONS. SHORT TERM MODEL TRENDS INDICATE THE UPPER LEVEL LOW OFF THE TEXAS GULF COAST WILL REMAIN NEARLY STATIONARY FOR THE NEXT 24 HOURS. SEVERAL SHORTWAVE TROUGHS ROTATING AROUND THIS UPPER LEVEL LOW WILL BRING INCREASING CHANCES FOR SHOWERS AND THUNDERSTORMS TO THE MID SOUTH. BEST CHANCES FOR SHOWERS AND THUNDERSTORMS STILL APPEARS TO BE MONDAY NIGHT INTO TUESDAY AS THE UPPER LEVEL LOW WEAKENS AND BECOMES ABSORBED INTO AN UPPER LEVEL TROUGH AXIS AND SHIFTS EAST TOWARDS THE TENNESSEE VALLEY BY WEDNESDAY. THIS WILL ALSO RESULT IN RAIN CHANCES GRADUALLY SHIFTING EAST ON WEDNESDAY. COOLER TEMPERATURES ARE EXPECTED FOR THE REMAINDER OF THE WEEK WITH THE EASTERN UNITED STATES BEING UNDER THE INFLUENCE OF THE UPPER LEVEL TROUGH. LONG TERM RUN TO RUN CONTINUITY ISSUES PERSIST FOR NEXT WEEKEND AS GFS/ECMWF MODELS DIFFER WITH RESPECT TO DEPTH OF THE EASTERN UNITED STATES TROUGH AXIS AND THE POTENTIAL FOR ANY PRECIPITATION ASSOCIATED WITH SHORTWAVES MOVING ALONG THE PERIPHERY OF THE UPPER LEVEL TROUGH AXIS. THUS...WILL GO WITH A PRECIPITATION FREE FORECAST FOR THE LONG TERM UNTIL MODELS COME INTO BETTER AGREEMENT. CJC && .AVIATION... 00Z TAFS LOW/MID LEVEL MOISTURE WILL FLOW NORTH INTO THE MIDSOUTH TONIGHT...AHEAD OF AN UPPER LOW CENTERED OVER THE SOUTHEAST TX COAST. MVFR CHANCES WILL INCREASE FIRST AT TUP THIS EVENING...AND MEM/MKL/JBR DURING THE OVERNIGHT. LATEST NAM AND HRRR GUIDANCE SUGGESTED DELAYING THE ONSET OF SHRA AND MVFR FROM EARLIER SOLUTIONS AND 00Z TAFS REFLECT THIS. PWB && .MEG WATCHES/WARNINGS/ADVISORIES... AR...NONE. MO...NONE. MS...NONE. TN...NONE. && $$
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
333 PM CDT SAT SEP 26 2015 .SHORT TERM... WV IMAGERY SHOWS AN UPPER LEVEL TROF QUICKLY PUSHING SOUTHWARD ACROSS THE WESTERN OK/WEST TX REGION. THIS TROF HAS BROUGHT WITH IT A COOL FRONT AS WELL AS SHOWERS AND THUNDERSTORMS. RAIN SHOWERS HAVE BEEN ONGOING ACROSS THE NORTHERN ROLLING PLAINS SINCE EARLY THIS MORNING AND ARE CONTINUING INTO THE AFTERNOON HOURS. THESE SHOWERS HAVE BEEN DRIVEN MORE SO BY WEAK ISENTROPIC UPGLIDE AND VERY WEAK INSTABILITY ALOFT DUE TO STEEPENING LAPSE RATES CAUSED BY THE OVERHEAD TROF. AIR COOLED RAIN IN ADDITION TO CLOUD COVER HAVE KEPT THE NORTHERN ROLLING PLAINS RATHER COOL WITH CHILDRESS SHOWING A TEMP OF 71F AS OF 19Z. TEMPS IN AREAS WHERE SKIES ARE MUCH CLEARER AND ARE AHEAD OF THE COOL FRONT HAVE REACHED INTO THE LOW TO MID 80S. THE FRONT IS CURRENTLY STALLED ALONG A LINE FROM DIMMITT TO POST COMPLETELY DISSECTING THE CITY OF LUBBOCK. ONE OF THE MAIN QUESTIONS WITH THE FRONT IS THE POSSIBILITY/DEVELOPMENT OF THUNDERSTORMS. SOME STORMS HAVE ALREADY DEVELOPED ACROSS MUCH OF GARZA COUNTY WHILE MOST STORMS HAVE STAYED JUST SOUTH OF THE FA. SOME LIGHT ECHOES ARE CURRENTLY SHOWING UP ON RADAR IN AND AROUND THE LUBBOCK AREA...EVEN AS FAR NORTH AS DIMMITT...BUT HAVE YET TO DO MORE THAN SPIT A DROP OR TWO OF RAIN. CU FIELD ON VIS IMAGERY CONTINUES TO INCREASE AS THE TROF CONTINUES TO STEEPEN LAPSE RATES ALOFT. MODEL SOUNDINGS FROM THE RAP ARE SHOWING THIS WELL AND...ALONG WITH THE HRRR...DEVELOP CONVECTION ALONG THE FRONT BY 20Z. SHOWERS AND THUNDERSTORMS WILL PUSH SOUTH TO SOUTHEASTWARD BY THE EARLY EVENING AS THE TROF PUSHES AWAY LEAVING THE BEST CHANCES FOR RAIN ACROSS THE ROLLING PLAINS OVERNIGHT INTO EARLY TOMORROW MORNING. WINDS WILL TURN BACK TO THE SOUTHEAST TOMORROW AS LIGHT RIDGING BUILDS BACK IN FROM THE WEST HELPING TO PREVENT ANY DECENT CHANCES FOR SHOWERS OR THUNDERSTORMS. TOMORROW AFTERNOON/S TEMPS WILL BE SIMILAR TO TODAY/S WITH THE EXCEPTION OF THE NORTHERN ROLLING PLAINS WHO SHOULD BE BACK INTO THE 80S. .LONG TERM... A DRY AND MILD FORECAST IS STILL ON TRACK FOR MOST OF NEXT WEEK AS AN UPPER RIDGE CENTERED OVER THE DESERT SOUTHWEST AND NORTHWEST MEXICO VERY GRADUALLY EXPANDS NORTHEASTWARD INTO THE SOUTHERN PLAINS. WE/LL SEE A PERSISTENT EASTERLY COMPONENT TO THE LOW- LEVEL WINDS THROUGH AT LEAST WEDNESDAY THOUGH WHICH SHOULD HELP KEEP TEMPS FROM WARMING MUCH ABOVE AVERAGE FOR LATE AUGUST...HIGHS IN THE 80S SHOULD BE THE RULE. SOUTH-SOUTHWEST FLOW WILL BE ON THE INCREASE THURSDAY INTO FRIDAY AS A MID-LEVEL TROUGH MOVES ACROSS THE INTER-MOUNTAIN REGION AND THIS MAY HELP PUSH TEMPS INTO THE UPPER 80S TO LOWER 90S RANGE. MEDIUM RANGE GUIDANCE BEGINS TO DIVERGE GREATLY BY NEXT WEEKEND...DUE TO THEIR DIFFERENCE IN HANDLING OF THE FAIRLY VIGOROUS TROUGH AS IT EMERGES INTO THE PLAINS...AS WELL AS THE NEXT SYSTEM MOVING THROUGH THE WEST. IT IS POSSIBLE THAT A COLD FRONT COULD BE SENT INTO THE AREA OR THE COLD AIR COULD REMAIN BOTTLED UP TO OUR NORTH. && .PRELIMINARY POINT TEMPS/POPS... FRIONA 53 82 56 84 / 10 0 0 0 TULIA 58 83 57 84 / 10 0 0 0 PLAINVIEW 59 83 57 85 / 10 10 0 0 LEVELLAND 58 85 58 85 / 20 0 0 0 LUBBOCK 59 84 60 86 / 20 10 0 0 DENVER CITY 58 85 57 85 / 20 0 0 0 BROWNFIELD 59 85 59 86 / 20 10 0 0 CHILDRESS 64 87 63 89 / 20 0 0 0 SPUR 63 86 61 87 / 20 10 0 0 ASPERMONT 64 89 63 89 / 30 10 0 0 && .LUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 51/33
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AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
951 PM EDT SUN SEP 27 2015 .SYNOPSIS... A COMPLEX AREA OF LOW PRESSURE ACROSS THE REGION WILL MAINTAIN A STRONG ONSHORE FLOW OF MOISTURE INTO THE AREA OVERNIGHT. THIS WILL COMBINE WITH A STRONG WEDGE OF HIGH PRESSURE ALONG THE APPALACHIANS AND LEAD TO CONTINUED WIDESPREAD RAIN OR DRIZZLE UNDER GUSTY NORTHEAST WINDS AND COOL TEMPERATURES. WEAK HIGH PRESSURE WILL BUILD INTO THE AREA ON MONDAY...BEFORE LOW PRESSURE APPROACHES FROM THE GULF COAST REGION BY MIDWEEK...POSSIBLY BRINGING ANOTHER ROUND OF HEAVIER RAINFALL BY TUESDAY. && .NEAR TERM /THROUGH MONDAY/... AS OF 951 PM EDT SUNDAY... HIGH PRESSURE REMAINS WEDGED AGAINST THE EASTERN SLOPES OF THE APPALACHIANS TONIGHT...MAINTAINING A COOL NORTHEAST WIND. AT THE SAME TIME...LOW PRESSURE OFF THE COAST CONTINUES TO PUSH DEEP MOISTURE INTO THE HIGHER TERRAIN. PERIODS OF RAIN...DRIZZLE AND FOG WILL CONTINUE OVERNIGHT INTO MONDAY MORNING. HEAVIER BANDS OF RAIN ARE DEVELOPING AND LIFT NORTH. RAINFALL OVERNIGHT WILL BE ENHANCE ALONG THE BLUE RIDGE WITH THE HEAVIEST AMOUNTS EXPECTED ALONG THE SOUTHERN BLUE RIDGE. ADJUSTED TEMPERATURES THIS EVENING INTO TONIGHT WITH THE LATEST OBS AND MODEL TRENDS. TEMPERATURES RUNNING COOLER IN SEVERAL AREAS THIS EVENING WITH RAIN AND CLOUDS. SHAPED THE NEXT COUPLE OF HOURS FOR POPS TOWARDS HIRESW-ARW- EAST...RUC AND HRRR WITH THE AXIS ON THE WEST. INCREASED QPF FOR TONIGHT ALONG SOUTHERN BLUE RIDGE AND WESTERN MOUNTAINS. WITH SATURATED GROUNDS...WE WILL HAVE TO WATCH FOR LOCALIZED FLOODING ISSUES OVERNIGHT INTO MONDAY MORNING. AS OF 650 PM EDT SUNDAY... MADE SOME MINOR ADJUSTMENTS IN TEMPERATURES AND DEW POINTS FOR THIS EVENING INTO TONIGHT. AS OF 330 PM EDT SUNDAY... FOR THIS EVENING AND TONIGHT...EXPECT LITTLE CHANGE FROM CURRENT CONDITIONS AS HIGH PRESSURE REMAINS WEDGED AGAINST THE EASTERN FACE OF THE APPALACHIANS...MAINTAINING A COOL NORTHEAST WINDFLOW ACROSS THE MID ATLANTIC. AT THE SAME TIME...LOW PRESSURE OFF THE COAST CONTINUES TO PUSH DEEP MOISTURE INTO THE HIGHER TERRAIN... RESULTING IN WIDESPREAD LOW CLOUDS AND SCATTERED BANDS OF RAIN. RAIN WILL CONTINUE AREAWIDE...REMAINING HEAVIEST/MOST PERSISTENT IN THE VICINITY OF THE BLUE RIDGE WHERE THE UPSLOPE CONDITIONS WILL AMPLIFY RAINFALL INTENSITY. AS SUCH...MAY SEE AN ADDITIONAL ONE TO TWO INCHES OF RAINFALL NEAR THE BLUE RIDGE PARKWAY THROUGH MONDAY MORNING. THE DEEP MOISTURE AND LOW CLOUDS WILL NOT ALLOW FOR MUCH COOLING OVERNIGHT HOWEVER...WITH OVERNIGHT LOWS EXPECTED TO RANGE FROM THE UPPER 50S TO THE LOW 60S. RAINFALL WILL BE MORE SPOTTY ON MONDAY AS HIGH PRESSURE WEDGING WEAKENS...AND ONSHORE FLOW OF MOISTURE DIMINISHES...MAKING MOISTURE MORE SHALLOW ACROSS OUR AREA. THAT STATED...EXPECT WE WILL STILL SEE SPOTTY BANDS OF RAIN MAKE THEIR WAY ACROSS THE AREA FROM THE COAST. WITH THE CONTINUED UPSLOPE FLOW...PERSISTENT AND OCCASIONALLY HEAVY RAINFALL CAN AGAIN BE EXPECTED ALONG THE BLUE RIDGE AND OTHER EAST FACING SLOPES. NEEDLESS TO SAY...DO NOT EXPECT WE WILL SEE CLOUDS BREAK OUT ANYWHERE OUTSIDE OF WESTERN TAZEWELL COUNTY...WHERE A FEW RAYS OF SUNSHINE MAY BE POSSIBLE DURING THE AFTERNOON. REGARDLESS...WITH LESS RAINFALL EXPECTED... BELIEVE AFTERNOON TEMPERATURES WILL BE WARMER...ALTHOUGH BELOW THE COOLER MAV GUIDANCE. MONDAY AFTERNOON HIGHS WILL RANGE FROM THE LOW/MID 60S ALONG THE RIDGES...TO THE LOW 70S ACROSS THE PIEDMONT. && .SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/... AS OF 330 PM EDT SUNDAY... OVERALL PATTERN DOES NOT CHANGE APPRECIABLY IN THE EARLY TO MID-WEEK PATTERN WITH UPPER LEVEL TROUGH TO THE WEST MAINTAINING VERY MOIST SOUTHERLY FLOW ALOFT INTO THE SOUTHERN APPALACHIANS AND MID-ATLANTIC REGION. HIGH PRESSURE OVER SOUTHEAST CANADA WILL ALSO KEEP SOME SEMBLANCE OF A WEDGE ACROSS THE AREA WITH EAST TO NORTHEAST FLOW IN THE LOWER LEVELS. SUN SEEKERS SHOULD DEFINITELY LOOK ELSEWHERE AS OVERCAST SKIES AND CHANCES FOR RAINFALL ARE VERY LIKELY TO PERSIST RIGHT INTO MID-WEEK AND BEYOND. A SLOW-MOVING COLD FRONT OVER THE MIDWEST AT THE OUTSET OF THE PERIOD WILL PUSH SLOWLY SOUTHEAST AND ACROSS THE FORECAST AREA TUESDAY...WITH INCREASING CHANCES FOR ORGANIZED RAINFALL AHEAD OF AND ALONG THE FRONT TUESDAY INTO WEDNESDAY. MODEL QPFS PER EURO/GFS RANGE FROM 1 TO 3+ INCHES FROM LATE MONDAY INTO LATE WEDNESDAY WHICH SUGGESTS A POSSIBILITY FOR RIVER FLOODING (SEE HYDRO SECTION BELOW) ACROSS BASINS WHICH HAVE BECOME MUCH MORE SATURATED WITH THIS WEEKENDS RAINFALL. TEMPS WILL HAVE NARROW DIURNAL RANGES DURING THE PERIOD WITH THE EXTENSIVE CLOUD COVER MAINLY FROM UPPER 50S/LOW 60S AT NIGHT TO UPPER 60S/LOW 70S IN THE DAY. && .LONG TERM /THURSDAY THROUGH SUNDAY/... AS OF 330 PM EDT SUNDAY... THE COLD FRONT SHOULD STALL OFF THE EAST COAST BY EARLY THURSDAY WITH ONE OR MORE WAVES OF LOW PRESSURE POSSIBLY DEVELOPING ALONG THIS BOUNDARY. TOO EARLY TO TELL EXACT POSITIONING AND EFFECTS OF ANY SUCH DEVELOPMENT...BUT 12Z GFS IS ACTUALLY QUITE WET ACROSS EVEN CENTRAL AND WESTERN CWA ON FRIDAY INTO EARLY SATURDAY SO AT LEAST CHANCE POPS ARE HELD IN THE GRIDS THROUGH SATURDAY ALTHOUGH STILL HAVE HIGHEST CHANCES IN THE EAST AND TRENDING TOWARD ONLY SLIGHT CHANCE IN THE FAR WEST. TEMPS SHOULD BE SLIGHTLY COOLER BEHIND THE FRONT WITH LOW 60S NW TO UPPER 60S SE FOR HIGHS AND MID 40S TO LOW 50S FOR LOWS. && .AVIATION /02Z MONDAY THROUGH FRIDAY/... AS OF 723 PM EDT SUNDAY... POOR FLYING CONDITIONS EXPECTED DURING THE PERIOD WITH LOW CLOUDS AND RAIN. HIGH PRESSURE CONTINUES TO MEANDER ALONG THE NEW ENGLAND COASTLINE...AS REMNANTS FROM THE SURFACE LOW CONTINUE TO DIP SOUTH ALONG THE SOUTHEASTERN SEABOARD. EASTERLY TO NORTHEASTERLY FLOW CONTINUES TO PUSH LOW TO MID LEVEL MOISTURE INLAND...KEEPING CEILINGS LOW AND THE AREA FAIRLY SATURATED. EXPECT MAINLY MVFR TO IFR VARIABLE CEILINGS THROUGH THE 28/00Z TAF PERIOD AREAWIDE...WITH VARIATIONS STEMMING FROM RAIN BANDS PASSING OVERHEAD. VISIBILITY VALUES WILL ALSO REMAIN VARIABLE. FOG AND DRIZZLE WILL FURTHER REDUCE THE VISIBILITY...ESPECIALLY ALONG THE BLUE RIDGE AND OTHER EAST FACING MOUNTAIN SLOPES. EAST TO NORTHEAST WINDS WILL REMAIN STRONG THROUGH THE OVERNIGHT WITH POTENTIAL GUSTS TO 25 KTS...ESPECIALLY ALONG THE RIDGES. KLWB/KBLF WILL CONTINUE TO SEE MINOR VARIATIONS IN WIND DIRECTION THROUGH THE PERIOD...SHIFTING MAINLY FROM EASTERLY TO SOUTHEASTERLY. HEAVIER BANDS OF RAIN AND POCKETS OF DENSE FOG WILL PRODUCE LOCAL LIFR CONDITIONS OVERNIGHT INTO MONDAY MORNING. FOR MONDAY...CEILINGS WILL REMAIN GENERALLY IFR IN MOST LOCATIONS...HOWEVER RAINFALL WILL BE MORE ON THE SCATTERED SIDE...WITH LIGHTER INTENSITY EXPECTED AS SOMEWHAT DRIER AIR WORKS INTO THE AREA...MAKING MOISTURE MORE SHALLOW. THE EXCEPTION WILL BE ALONG THE BLUE RIDGE...WHERE UPSLOPE FLOW WILL CONTINUE TO ENHANCE RAINFALL INTENSITY/AMOUNTS LOCALLY. FOG AND DRIZZLE WILL STILL BE AN ISSUE AS WELL...ESPECIALLY ALONG EAST FACING SLOPES. MEDIUM CONFIDENCE IN CEILINGS...VISIBILITIES AND WINDS DURING THE PERIOD. EXTENDED AVIATION DISCUSSION... IFR/LOW END MVFR CONDITIONS WILL REMAIN ACROSS THE AREA MONDAY EVENING INTO EARLY TUESDAY...IN ADDITION TO SPOTTY RAINFALL AND POCKETS OF DRIZZLE. ANOTHER STORM SYSTEM WILL APPROACH LATE TUESDAY...BRINGING ANOTHER ROUND OF POTENTIALLY HEAVY RAIN...AS WELL AS SUB VFR CEILINGS/VISIBILITIES INTO WEDNESDAY. DRIER AIR WILL ATTEMPT TO PUSH THE DEEPER MOISTURE OFFSHORE ON THURSDAY AS A COLD FRONT PASSES TO THE SOUTHEAST. HOWEVER...A DEVELOPING WEDGE MAY KEEP MVFR CEILINGS IN PLACE FOR LATE IN THE WEEK. && .HYDROLOGY... AS OF 345 PM EDT SUNDAY... SMALLER STREAMS AND CREEKS HAVE CRESTED FOR THE MOST PART WITH NOTHING HAVING REACHED EVEN ACTION STAGE DESPITE WIDESPREAD 1 TO 4 INCHES IN 72 HOURS AND UP TO 8 OR MORE INCHES OF IN ISOLATED PARTS OF THE BLUE RIDGE. THE HEAVIEST RAIN FELL IN THE UPPER REACHES OF THE DAN AND SMITH RIVER BASINS AND WHATEVER RUNOFF OCCURRED WILL BE MAKING ITS WAY DOWNSTREAM. PHILPOTT RESERVOIR CAUGHT A SUBSTANTIAL PORTION OF THE SMITH RIVER BASIN RUNOFF WITH THE RESERVOIR ELEVATION CLIMBING OVER 2 FEET OVER THE PAST TWO DAYS. FURTHER DOWNSTREAM THE DAN IS STILL RISING ALONG ITS ENTIRE REACH BUT IS STILL CURRENTLY FORECAST TO CREST BELOW ACTION STAGE EVEN AT FLOOD-PRONE SOUTH BOSTON. WITH MORE RAIN ON THE WAY SOME OF IT POSSIBLY HEAVY... ESPECIALLY TUESDAY INTO WEDNESDAY AND POSSIBLY AGAIN LATER IN THE WEEK IT WOULD BE PRUDENT TO PAY CLOSE ATTENTION TO RIVER FORECASTS AS THEY WILL LIKELY BE UPDATED FREQUENTLY. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ SYNOPSIS...NF NEAR TERM...KK/NF SHORT TERM...PC LONG TERM...AMS/PC AVIATION...JM/KK/NF HYDROLOGY...JH/MBS
AREA FORECAST DISCUSSION...CORRECTED
NWS MILWAUKEE/SULLIVAN WI
326 PM CDT SAT SEP 26 2015 .SHORT TERM... TONIGHT - CONFIDENCE...MEDIUM SURFACE FRONT MOVES INTO THE DAKOTAS WITH HIGH PRESSURE ACROSS THE EAST COAST. LINGERING ANTICYCLONIC CURVATURE IN THE LOW LEVELS WILL KEEP THINGS QUIET. SURFACE/925 FLOW STARTS TO TURN FROM THE EAST MORE TO SOUTH OR SE AS THE NIGHT WEARS ON. WEAK VORT AXIS SHIFTS NORTH FROM IN/OH INTO LWR MI. LLVL RH PROGS SHOW MOISTURE ON THE INCREASE FROM SE TO NW ACRS THE CWA ESP AFTER 6Z. THIS EVIDENT ON VSBL SATL IMGRY ACRS SRN IL INTO IN AND OH WITH A NW DRIFT/EXPANSION OF THE CLOUD SHIELD. THE NAM IS STILL A BIT FEISTY WITH FOG AND VRY LOW STRATUS DEVELOPING ACROSS THE EAST...ESP NEAR THE LAKE. GFS IS MUCH DRIER. RAP AND NAM SOUNDINGS SHOWING SHALLOW SATURATION BY MID EVENING ...BRIEF ON THE RAP BUT LONGER ON THE NAM. DO HAVE FOG MENTIONED BUT TIMING TRICKY ESP WITH CLOUD COVER ADVANCING FROM THE SE. MOS AND SREF DO SHOW SPOTTY COVERAGE TO ANY DENSE POCKETS WITH OVERALL LESS PROB OF DENSE THAN LAST NIGHT...BUT WILL HAVE TO KEEP AN EYE NEAR THE LAKE MI SHORE WITH A MIDGE HIGHER DEW POINTS THERE IN THE U50S/L60S. .SUNDAY - CONFIDENCE...MEDIUM BROAD ANTICYCLONIC LOW LEVEL FLOW CONTINUES WITH AN OVERALL SRLY FLOW BETWEEN THE EASTERN HIGH AND COLD FRONT PUSHING EAST FROM THE DAKOTAS. THE MODELS HAVE BEEN CONSISTENT WITH THE LLVL MOISTURE PUSH NORTHWARD THROUGH THE AREA AND EXPECT A GOOD DEAL OF CLOUD COVER BUT FOR NOW NOT SEEING THE FORCING OR DEPTH OF MOISTURE TO JUSTIFY THE 20-35 POPS BEING GENERATED BY MOS. SO WILL KEEP DRY FCST IN PLACE. .LONG TERM... SUNDAY NIGHT AND MONDAY... FORECAST CONFIDENCE HIGH. LOW LEVEL MOISTURE IS EXPECTED TO LINGER OVER SOUTHERN WI SUNDAY NIGHT. FORECAST SOUNDINGS ARE SHOWING ELEVATED WINDS JUST ABOVE THE SURFACE INVERSION SO NOT EXPECTING MUCH FOG. THE BIG QUESTION IS WHETHER OR NOT SKIES WILL SCATTER/CLEAR OUT SUNDAY EVENING TO VIEW THE LUNAR ECLIPSE. WITH LACK OF ANY UPWARD FORCING... I TRENDED THE FORECAST TOWARD LOWER SKY COVER. SOUTH CENTRAL WI WILL HAVE A BETTER CHANCE TO SEE BREAKS IN THE CLOUDS THAN SOUTHEAST WI. SCATTERED SUNSHINE AND WEAK WARM AIR ADVECTION ACROSS SOUTHERN WI ON MONDAY AHEAD OF AN APPROACHING FRONT WILL ALLOW TEMPS TO RISE INTO THE UPPER 70S. THERE IS FAIRLY GOOD AGREEMENT IN MODELS FOR A DRY FORECAST IN THE MKX AREA THROUGH MONDAY AFTERNOON. MONDAY NIGHT AND TUESDAY... FORECAST CONFIDENCE MEDIUM. THE SURFACE COLD FRONT WILL SLIDE SOUTH THROUGH SOUTHERN WI MONDAY NIGHT. THE SHOWERS ASSOCIATED WITH THE FRONT WILL BE POST-FRONTAL DUE TO A SHORTWAVE SLIDING ACROSS WI WITHIN THE 850MB BAROCLINIC ZONE THAT LAGS JUST BEHIND THE SURFACE FRONT. MODELS HAVE COME INTO BETTER AGREEMENT WITH THE TIMING... BUT PRECIP AMOUNTS STILL DIFFER. EXPECTING ONLY A BRIEF TIME PERIOD FOR SHOWERS... SO AMOUNTS WILL BE ON THE LIGHTER SIDE. INSTABILITY LOOKS VERY WEAK AND THE FRONT WILL BE MOVING THROUGH DURING THE NIGHT SO REMOVED MENTION OF THUNDER. HIGHS TUESDAY WILL BE IN THE 60S. TUESDAY NIGHT WILL BE CHILLY WITH EXPECTED CLEAR SKIES AND COLD AIR ADVECTION. LEANED TOWARD THE COOLER SIDE OF GUIDANCE. WEDNESDAY THROUGH SATURDAY... FORECAST CONFIDENCE MEDIUM. SURFACE HIGH PRESSURE WILL SET UP OVER THE WESTERN GREAT LAKES THROUGH THURSDAY. THE WEATHER SHOULD BE DRY DURING THIS TIME ALTHOUGH SMALL POPS LINGER IN THE FORECAST DUE TO A PREVIOUSLY WETTER FORECAST. THEN AN UPPER LOW PRESSURE TROUGH IS EXPECTED TO IMPACT WI THU NIGHT INTO FRI WITH POSSIBLE SHOWERS. THERE ARE LARGE DIFFERENCES IN THE UPPER LEVEL PATTERNS OF THE MODELS LATER IN THE WEEK INTO NEXT WEEKEND... BUT THERE IS NO GOOD SIGNAL FOR A DECENT CHANCE FOR PRECIP. && .AVIATION/00Z TAFS/...INLAND CU FILED TO DISSIPATE DIURNALLY WITH SHORELINE STRATUS DECK NORTH OF KMKE GRADUALLY ERODING. SREF CIG/VIS PROB PROG SHOWS BETTER FOG POTENTIAL TONIGHT ACROSS NW CWA WITH INCREASING MOISTURE WITH WAVE RIDING NWWD FROM THE OH VLY. SOME MVFR CIGS POSSIBLE WITH THIS ON SUNDAY. MET MOS/NAM SHOWING IFR CIG POTENTIAL FOR SUNDAY MORNING THOUGH MOISTURE FIELDS MAY BE OVERDONE ON THE NAM. WILL HAVE TO KEEP AN EYE NEAR THE LAKE AS SLIGHTLY HIGHER DEW POINTS FOUND THERE. && .MKX WATCHES/WARNINGS/ADVISORIES... WI...NONE. LM...NONE. && $$ TONIGHT/SUNDAY AND AVIATION/MARINE...COLLAR SUNDAY NIGHT THROUGH SATURDAY...MRC
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
1134 PM MDT SUN SEP 27 2015 .UPDATE... ISSUED AT 956 PM MDT SUN SEP 27 2015 SOME THIN HIGH CLOUD ACROSS THE FORECAST AREA...BUT MUCH OF THE REGION IS ABLE TO OBSERVE THE SUPERMOON ECLIPSE. THE HRRR MAY BE OVERDOING THE THREAT OF PRECIPITATION OVER THE UINTA MOUNTAINS TONIGHT. DO NOT SEE ANY EVIDENCE THAT SHOWERS ARE FORMING ON SALT LAKE`S RADAR OUR OURS...SO TEMPERED THE POP GRIDS A BIT IN THE EVENING UPDATE. APPEARED THAT SHOWERS DID FORM ALONG THE NRN BORDER OF DAGGETT COUNTY BEFORE SUNSET...BUT THESE HAVE SINCE DISSIPATED. && .SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT) ISSUED AT 326 PM MDT SUN SEP 27 2015 THE UPPER RIDGE THAT HAS BEEN OVER THE REGION WILL CONTINUE TO FLATTEN AND SHIFT TO THE SOUTHWEST DURING THE NEXT COUPLE OF DAYS. AS A RESULT THE FLOW WILL BECOME MORE WESTERLY AND CARRY A COUPLE OF WEAK WAVES FROM WEST TO EAST...MAINLY NORTH OF OUR FORECAST AREA. THE TAIL END OF ONE WAVE WILL BRUSH OUR NORTHERN EDGE TONIGHT. AS A RESULT WE HAVE SEEN A BETTER CUMULUS DEVELOPMENT OVER THE UINTA...FLATTOPS AND PARK RANGES THIS AFTERNOON. A FEW SHOWERS AND THUNDERSTORMS MAY ALSO DEVELOP LATE THIS AFTERNOON AND EARLY THIS EVENING. OF MOST INTEREST FOR TONIGHT`S FORECAST WILL BE THE AMOUNT OF EXPECTED CLOUD COVER FOR THE LUNAR ECLIPSE THIS EVENING. IT APPEARS SOME HIGH CLOUDS MAY FILTER THE VIEW FOR MUCH OF THE AREA...BUT THESE CLOUDS WILL GENERALLY BE THIN. THE EXCEPTION WILL BE FROM AROUND THE TAVAPUTS PLATEAU/FLATTOPS AND NORTH...WHERE CLOUDS MAY BE A LITTLE THICKER. BUT EVEN THERE THE MOON SHOULD BE SOMEWHAT VISIBLE. OVERNIGHT TEMPS ARE EXPECTED TO BE A LITTLE WARMER DUE TO THE BETTER CLOUDS. ENERGY WILL CONTINUE TO ROUND THE TOP OF THE RIDGE AND BRUSH THE NORTHERN EDGE OF OUR FORECAST AREA THROUGH MON NIGHT. THEREFORE A FEW SHOWERS AND LATE DAY THUNDERSTORMS WILL CONTINUE TO BE POSSIBLE ACROSS THE NORTH...FAVORING THE HIGHER TERRAIN. LITTLE CHANGE IS EXPECTED IN AFTERNOON HIGH TEMPERATURES ON MONDAY... WITH LOWS INCREASING JUST A LITTLE MONDAY NIGHT. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 326 PM MDT SUN SEP 27 2015 A FEW SHOWERS AND THUNDERSTORMS WILL CONTINUE OVER THE NORTH ON TUESDAY...POSSIBLY LINGERING OVERNIGHT AS ANOTHER WAVE BRUSHES THE FORECAST AREA. ON WED THE RIDGE WILL REBOUND ALONG THE UT/CO BORDER...PUMPED UP BY THE NEXT LOW PRESSURE TROUGH APPROACHING THE WEST COAST. WHILE THE MID TERM MODELS ARE IN FAIR AGREEMENT ON THE BIG PICTURE...THERE CONTINUES TO BE SOME RATHER SIGNIFICANT TIMING DIFFERENCES IN WHEN THIS LOW PRESSURE SYSTEM AND ITS ASSOCIATED COLD FRONT WILL REACH THE FORECAST AREA...AND IN HOW QUICK THE TROUGH EXITS TO THE EAST. IN ANY CASE...THE RIDGE WILL DOMINATE WED AND THU AHEAD OF THE TROUGH. SOUTHWEST WINDS WILL PICK UP ON THU AS THE GRADIENT TIGHTENS AHEAD OF THE SYSTEM AS IT MOVES INTO THE GREAT BASIN. THE ECMWF IS FASTER BY AROUND 12 HOURS...WITH THE COLD FRONT JUST ABOUT TO OUR NORTHWEST CORNER AT 00Z FRI. THE EC ALSO SHOWS THE LOW CENTER QUICKLY BRUSHING OUR NORTHERN EDGE EARLY FRIDAY AND EAST OF THE FORECAST AREA BY THE AFTERNOON. A SHORTWAVE RIDGE THEN FOLLOWS FOR SUN. AS MENTIONED ABOVE...THE GFS IS AROUND 12 HOURS SLOWER...WITH THE FRONT REACHING THE NORTHWEST CORNER AT AROUND 12Z FRI. IN THIS SOLUTION THE LOW CENTER WILL MOVE OVER NE UT/NW CO/SW WY FRI EVENING...AND LINGER OVER NORTHWEST CO THROUGH EARLY SAT. ENERGY THEN SPLITS OFF THE MAIN LOW AND RETROGRADES...LEAVING GENERAL TROUGHINESS OVER WY TO THE GREAT BASIN THROUGH SUN. FOR NOW HAVE KEPT THE BEST CHANCE OF SHOWERS/THUNDERSTORMS ON FRI AFTERNOON...WITH A DOWNTURN AFTER THAT. EXPECT THAT THE FORECAST WILL CONTINUE TO BE ADJUSTED AS THIS SYSTEM NEARS AND MODEL SOLUTIONS EVOLVE. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 1130 PM MDT SUN SEP 27 2015 ISOLATED SHOWERS AND THUNDERSTORMS WILL DEVELOP OVER THE MOUNTAINS AFTER 19Z MONDAY AND LINGER THROUGH 02Z MONDAY EVENING. STORMS WILL PRODUCE GUSTY OUTFLOW WINDS TO 35 MPH AND ONLY LIGHT RAINFALL AMOUNTS. OTHERWISE...VFR CONDITIONS WILL BE HOLDING IN PLACE THROUGH MONDAY NIGHT WITH SFC WINDS GENERALLY UNDER 15 KTS. && .GJT WATCHES/WARNINGS/ADVISORIES... CO...NONE. UT...NONE. && $$ UPDATE...PF SHORT TERM...EH LONG TERM...EH AVIATION...JDC
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
521 AM EDT MON SEP 28 2015 ...A CLOSE CALL FOR HEAVY RAINFALL ALONG THE FLORIDA WEST COAST LATER TODAY THROUGH TUESDAY MORNING... ...FLOOD WATCH IN EFFECT FOR COASTAL COUNTIES FROM SARASOTA NORTHWARD TO LEVY... .SYNOPSIS... 08Z WATER VAPOR AND H4 RAP ANALYSIS SHOWS A VERY STAGNANT UPPER LEVEL SYNOPTIC PATTERN IN PLACE ACROSS THE CONUS EARLY THIS MORNING. THE MAIN FEATURES OF NOTE HAVE NOT MOVED MUCH SINCE EARLY SUNDAY MORNING. THE MAIN NORTHERN STREAM FLOW REMAINS CONFINED OVER SOUTHERN CANADA...AS IT RIDES UP AND OVER AN UPPER RIDGE IN PLACE ACROSS THE DESERT SOUTHWEST. THE UPPER LEVEL PATTERN FURTHER TO THE EAST AND SOUTH OVER OUR REGION IS QUITE COMPLEX. A DEEP TROUGH ANCHORED BY A LARGE CLOSED UPPER LOW FEATURE OVER THE TEXAS COAST REMAINS STALLED TO OUR WEST...WHILE THESE HEIGHT FALLS HAVE PROMOTED A STRENGTHENING UPPER RIDGE OFF THE FLORIDA EAST COAST. THE HEIGHT GRADIENT BETWEEN THESE FEATURES IS ALLOWING A DEEP...AND MOIST...SOUTH TO SOUTHWEST FLOW FROM THE CENTRAL GULF OF MEXICO TO THE WESTERN FLORIDA PENINSULA. WV IMAGERY SHOWS A DEEP MOISTURE PLUME OUT OF THE NW CARIBBEAN MOVING OVER OUR HEADS...AND THE 28/12Z KTBW SOUNDING PROFILE AGAIN SAMPLED A COLUMN WITH AN OVER 2" PW VALUE. THE MEASURED VALUE OF 2.12" IS MORE THAN THE 90TH PERCENTILE OF VALUES FOR THE END OF SEPTEMBER. PERIODIC WEAK IMPULSES EMBEDDED WITHIN THE SOUTHERLY FLOW ALOFT HAVE BEEN PROVIDING THE FOCUS FOR CLUSTERS OF SHWRS/STORMS WORKING ALONG/JUST OFF THE SUNCOAST EARLY THIS MORNING. ALTHOUGH THE FORCING WITH THESE FEATURES IS WEAK...THE DEEP MOISTURE IN THE COLUMN AND GENERAL WEAK DIFFLUENCE ALOFT IS COMBINING TO PRODUCE EFFICIENT CONVECTION AHEAD OF EACH IMPULSE. AT THE SURFACE...A WEAK AREA OF LOW PRESSURE HAS EMERGED OFF THE YUCATAN PENINSULA AND IS SLOWLY MOVING NORTHWARD THROUGH THE CENTRAL GULF OF MEXICO. OUR LOW LEVEL FLOW IS GENERALLY A LIGHT INFLOW FROM THE EAST/ESE RIGHT NOW...BUT WILL BE VEERING TOWARD THE SOUTH TODAY AS THE LOW CONTINUES TO TRACK NORTHWARD TOWARD THE NORTH-CENTRAL GULF COAST. THE TRACK OF THIS LOW CONTINUES TO BE QUITE PROBLEMATIC FOR OUR FORECAST. FOR SEVERAL DAYS THE NWP GUIDANCE HAS SUGGESTED THIS SYSTEM WOULD PLACE THE FL WEST COAST ON THE VERY EDGE OF THE BEST SYNOPTIC FORCING/HEAVY RAIN POTENTIAL. WE WERE HOPING THAT AS THE EVENT DREW NEAR...A TREND EAST OR WEST WOULD OCCUR...MAKING THE FORECAST MORE DEFINITIVE TOWARD WET OR DRY. HOWEVER...THIS DEVIATION TOWARD THE LEFT OR RIGHT HAS NOT OCCURRED IN THE SIMULATIONS...AND THE GUIDANCE CONSENSUS HOLDS ONTO THE "MIDDLE OF THE ROAD" TRACK AND ORGANIZATION STRUCTURE. UNFORTUNATELY...THIS RESULTS IN THE FORECAST TODAY AGAIN BEING OF LOWER CONFIDENCE THAN USUAL...DUE TO THE IMPLICATIONS THAT ONLY SMALL DEVIATIONS IN TRACK OR ORGANIZATION OF THE LOW MAY HAVE FOR OUR LOCAL WEATHER (HEAVIER RAIN POTENTIAL ALONG THE COAST VS. STAYING JUST OFFSHORE). && .SHORT TERM (TODAY THROUGH TUESDAY)... AS MENTIONED IN THE SYNOPSIS ABOVE...THE MAIN FORECAST DILEMMA FOR THE SHORT TERM IS THE POTENTIAL FOR PERIODS OF HEAVY RAINFALL ALONG THE COAST ASSOCIATED WITH A WEAK AREA OF LOW PRESSURE MOVING NORTHWARD THROUGH THE CENTRAL/EASTERN GULF. ALREADY SEEING LOTS OF STORMS ACROSS THE EASTERN GULF OF MEXICO ASSOCIATED WITH THIS SYSTEM...AND THESE WILL BE APPROACHING THE COAST LATER THIS MORNING. ALMOST ALL THE GUIDANCE SUGGESTS A VERY CLOSE CALL AS TO WHETHER OR NOT THE HEAVIER AND MORE PROLONGED RAINFALL REACHES THE COAST OR STAYS JUST OFFSHORE. THE ISSUE AT HAND IS THAT IF THE STORM TRACKS A BIT FURTHER EAST AND THE BANDS BECOME ESTABLISHED ALONG THE COAST...THE AVAILABLE MOISTURE IN THE COLUMN IS VERY HIGH...AND THE SQUALLS/BANDS ARE LIKELY TO BE VERY EFFICIENT AT PRODUCING HEAVY RAINFALL. THERE IS UNCERTAINTY IN THIS FORECAST DUE TO THE LIKELY TIGHT SPATIAL GRADIENT IN RAINFALL...BUT THE POTENTIAL FOR SOME LOCATIONS TO SEE HEFTY RAINFALL AMOUNTS... COMBINED WITH ALREADY ELEVATED RIVER LEVELS...WARRANTS THE ISSUANCE OF A FLOOD WATCH. THIS FLOOD WATCH IS FOR ONLY THE COASTAL COUNTIES FROM SARASOTA NORTHWARD TO LEVY. PERHAPS WE WILL LUCK OUT AND THE FLOODING TYPE RAINS TEASE US JUST OFFSHORE...AND NEVER REALLY MAKE IT TO OUR LAND ZONES. WILL BE MONITORING RADAR AND NWP GUIDANCE TRENDS. EVEN IF "HEAVY" RAINFALL TOTALS DO NOT MATERIALIZE...THE RAIN CHANCES ARE GOING TO BE HIGH FOR THE REGION DUE TO BOTH THE GULF LOW...AND THE HIGH COLUMN MOISTURE FORCING DIURNALLY PRODUCED STORMS. THEREFORE...MOST LOCATIONS ARE FORECAST WITH LIKELY POPS. DEPENDING ON THE EVOLUTION OF THE BANDS...MAY VERY WELL HAVE TO FURTHER INCREASE THESE RAIN CHANCES TO CATEGORICAL ACROSS THE FLOOD WATCH AREA WITH FUTURE FORECAST UPDATES. AT LEAST FOR NOW...MOST OF THE MORNING SHOULD BE ON THE DRY SIDE...OUTSIDE OF A FEW ISOLATED SPRINKLES. THE REAL THREAT FOR HEAVY RAINFALL (IF IT MATERIALIZES) WILL BE LATER THIS AFTERNOON INTO TONIGHT. DO NOT EXPECT MUCH IN THE WAY OF SUN TODAY...DEEP TROPICAL MOISTURE WILL BE STREAMING OVERHEAD ALL DAY...KEEPING OUR SKIES MOSTLY CLOUDY. THESE CLOUDS WILL ALSO KEEP TEMPERATURES DOWN IN THE 80S FOR MOST SPOTS TODAY. THE MAJORITY OF THE GUIDANCE GIVES THE BEST PUSH OF RAIN/STORM POTENTIAL ASSOCIATED WITH THE LOW INTO THE COASTAL AREAS TONIGHT. THE HIGH POPS OF LIKELY TO CATEGORICAL WILL CONTINUE ALONG THE COAST. LATE TONIGHT...CONDITIONS IN THE LOWER LEVELS OVER THE NORTHEAST GULF OF MEXICO AND ALONG THE COAST FROM TAMPA NORTHWARD WILL FEATURE DECENT VALUES BETWEEN 20-25KTS OF 0-1KM AND 0-3KM SHEAR. WILL HAVE TO MONITOR STORMS APPROACHING THE COAST VERY CLOSELY...AS THIS SHEAR WILL HELP INDUCE SOME ROTATION/ENHANCED UPDRAFTS. IT DOES APPEAR THAT CONDITIONS WILL SUPPORT A SMALL THREAT FOR A FEW WATERSPOUTS OR WEAK TORNADOES WITH STRONGER STORM MOVING ASHORE. WILL BE WATCHING THIS POTENTIAL WITH LATER GUIDANCE PACKAGES. HOWEVER...WIDESPREAD SEVERE WEATHER IS NOT EXPECTED...AND HOPEFULLY ANY ROTATING STORM WILL BE ISOLATED IN NATURE...AND REMAIN OFFSHORE. TUESDAY THE LOW IS EXPECTED TO MOVE ASHORE NEAR THE FLORIDA PANHANDLE...WEAKEN AND EVENTUALLY SHEAR OUT TO OUR NORTH. AS THE LOW GOES BY OUR LATITUDES...THE FLOW WILL VEER TO THE SOUTHWEST THROUGH A DEEP LAYER OF THE ATMOSPHERE. THIS SOUTHWEST FLOW AND STILL VERY HIGH COLUMN MOISTURE WILL CONTINUE TO HELP PROMOTE SHOWERS AND STORMS TO MOVE ASHORE ALONG WESTERN FLORIDA. THE BANDS DO NOT LOOK TO BE AS WIDESPREAD ON TUESDAY AS THEY MAY BE LATER TODAY AND TONIGHT...HOWEVER...SMALLER SCALE CONVERGENCE ZONES WOULD SUGGEST THE THREAT FOR LOCALIZED TRAINING OF STORMS OVER CERTAIN LOCATIONS. THEREFORE...THE FLOOD WATCH WILL BE ALLOWED TO CONTINUE INTO EARLY TUESDAY AFTERNOON. LATER IN THE DAY TUESDAY...THERE ARE SOME INDICATIONS THAT THINGS MAY TRY TO DRY OUT ACROSS THE NATURE COAST...AND HAVE TRENDED POPS DOWN TO THE NORTH OF THE I-4 CORRIDOR AFTER 18Z. BETTER CHANCES FOR CONTINUED SHOWERS OFF THE GULF WILL BE FROM TAMPA SOUTHWARD ALONG THE SUNCOAST. IT IS HIGHLY LIKELY THAT MOST AREAS WILL SEE A WETTING RAIN DURING THE NEXT 24 TO 30 HOURS. HOWEVER...INLAND AREA WILL EXPERIENCE MORE OF A SUMMER-LIKE PATTERN OF PASSING SHOWER AND STORMS. IT IS THE IMMEDIATE COAST WHERE THE THREAT FOR PROLONGED RAIN LOOKS HIGHEST. HAVE A GREAT MONDAY EVERYONE! && .LONG TERM (WEDNESDAY THROUGH NEXT SUNDAY)... U/L TROUGH WILL PERSIST OVER THE EASTERN U.S. WEDNESDAY...WITH S/W ENERGY DIGGING THROUGH THE OHIO RIVER VALLEY THURSDAY REINFORCING THE TROUGH OVER THE REGION. NEXT UPSTREAM S/W WILL DIG FURTHER WEST OVER THE CENTRAL ROCKIES WHICH WILL KICK OUT THE TROUGH OVER THE SOUTHEAST...WITH ZONAL U/L FLOW DEVELOPING ACROSS THE SOUTHERN TIER OF THE U.S. SATURDAY AND SUNDAY. AT THE SURFACE...AREA OF LOW PRESSURE WILL BE OFF THE SOUTHEAST U.S. COAST WEDNESDAY WITH BOUNDARY EXTENDING ACROSS SOUTH FLORIDA WITH SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS OVER THE CENTRAL AND SOUTHERN FORECAST AREA...WITH GREATEST AREAL COVERAGE OVER SOUTHWEST FLORIDA. DEEP TROPICAL MOISTURE WILL REMAIN OVER THE REGION WITH PCPW VALUES ABOVE 2 INCHES ACROSS THE CENTRAL AND SOUTHERN PENINSULA WHICH WILL CONTINUE THE THREAT FOR LOCALLY HEAVY RAIN. SIMILAR SET- UP ON THURSDAY HOWEVER THE DEEP LAYER MOISTURE WILL SLOWLY BE SUPPRESSED TO THE SOUTH THROUGH THE DAY. THE AREA OF LOW PRESSURE OFF THE SOUTHEAST COAST WILL LIFT SLOWLY OUT FRIDAY NIGHT AND SATURDAY WITH DRIER AIR SURFACE AND ALOFT ADVECTING DOWN THE BACKSIDE OVER WEST CENTRAL AND SOUTHWEST FLORIDA OVER THE WEEKEND...WITH DEW POINTS DROPPING INTO THE 60S AND SLIGHTLY COOLER TEMPERATURES. && .AVIATION... VFR CONDITIONS PREVAIL ACROSS WEST-CENTRAL AND SOUTHWEST FLORIDA EARLY THIS MORNING. OTHER THAN SOME LIGHT SPRINKLES...ANY SIGNIFICANT RAINFALL SHOULD STAY OFFSHORE THROUGH 15Z. THEREAFTER INCREASING CHANCES FOR SHOWER AND STORMS WILL ENTER THE FORECAST FOR ALL TAF SITES. THE BEST POTENTIAL FOR LONGER DURATION RAINFALL WILL BE AT KTPA/KPIE/KSRQ AFTER 16Z. PERIODIC SHOWER AND STORMS WILL MOVE ASHORE FROM THE GULF OF MEXICO INTO TUESDAY MORNING WITH MVFR CIG/VIS RESTRICTIONS ACCOMPANYING THE BANDS. && .MARINE... A WEAK AREA OF LOW PRESSURE WILL MOVE NORTHWARD THROUGH THE CENTRAL AND EASTERN GULF OF MEXICO THROUGH TONIGHT. SOUTHEAST TO SOUTH WINDS TO THE EAST OF THIS LOW WILL REACH CAUTIONARY LEVELS AT TIMES THROUGH TONIGHT...ESPECIALLY AWAY FROM THE COAST. IN ADDITION NUMEROUS SHOWER AND THUNDERSTORM SQUALL ARE EXPECTED OVER THE COASTAL WATERS WHERE WIND AND SEAS MY BE MORE ROUGH. THE LOW WILL WEAKEN AND MOVE AWAY FROM THE REGION LATE TUESDAY INTO WEDNESDAY...WITH A LIGHTER WEST OR SOUTHWEST FLOW DEVELOPING ACROSS THE EASTERN GULF OF MEXICO. && .FIRE WEATHER... THE FORECAST WILL FEATURE ABUNDANT LOW LEVEL MOISTURE THROUGH THE EARLY PORTION OF THE WEEK. RELATIVE HUMIDITY VALUES WILL BE WELL ABOVE CRITICAL VALUES AND MOST SPOTS WILL RECEIVE WETTING RAINFALL BOTH MONDAY AND TUESDAY. THE HEAVIEST RAINFALL AND LONGEST DURATION RAINFALL IS LIKELY TO BE ALONG THE IMMEDIATE COAST THE NEXT COUPLE OF DAYS. FOG POTENTIAL... NO SIGNIFICANT FOG OR REDUCED VISIBILITY IS EXPECTED THE NEXT SEVERAL DAYS. && .PRELIMINARY POINT TEMPS/POPS... TPA 86 76 86 77 / 60 60 70 30 FMY 89 77 87 75 / 50 50 60 40 GIF 88 75 87 75 / 60 50 60 30 SRQ 85 78 85 77 / 60 70 70 30 BKV 86 74 86 74 / 70 60 70 30 SPG 86 77 85 78 / 60 70 70 40 && .TBW WATCHES/WARNINGS/ADVISORIES... FL...FLOOD WATCH FROM 2 PM EDT THIS AFTERNOON THROUGH TUESDAY AFTERNOON FOR COASTAL CITRUS-COASTAL HERNANDO-COASTAL HILLSBOROUGH-COASTAL LEVY-COASTAL MANATEE-COASTAL PASCO-COASTAL SARASOTA-INLAND CITRUS-INLAND HERNANDO- INLAND HILLSBOROUGH-INLAND LEVY-INLAND MANATEE-INLAND PASCO-INLAND SARASOTA-PINELLAS. GULF WATERS...NONE. && $$ SYNOPSIS/SHORT TERM/AVIATION/MARINE/FIRE WX...MROCZKA LONG TERM...13/OGLESBY
AREA FORECAST DISCUSSION
NWS TALLAHASSEE FL
331 AM EDT MON SEP 28 2015 ...Flash Flood Watch Now in Effect for Parts of the Region... .Near Term [Through Today]... The 1 am EDT regional surface analysis, with the help of a midnight ASCAT pass, showed an elongated cyclonic circulation centered roughly 100 miles north of the Yucatan Peninsula. The nearest deep moist convection remained 100 miles east of the ill-defined center, owing to 30 KT of southwest shear over this region. There was another weak low centered off the TX-LA coast, associated with a mid- upper tropospheric low over east TX. A zone of frontogenesis extended east of this low across central FL. Vapor imagery and upper air data showed deep southerly flow from the western Caribbean Sea through our forecast area, with precip water values 50% above climo. The forecast challenge today isn`t will it rain, but how much. The global models` highest QPF values are south and west of our forecast area. While our local ensemble of Convection Allowing Models (ECAM) show this as well to some degree, they still forecast high QPF values across our FL zones. It appears that the global models are precipitating out most of the tropospheric moisture along the developing east-west frontal boundary, while the CAMs allow convection to occur north of this boundary. The ECAM has shown considerable skill at forecasting heavy rain events in our region the past few years, and we have followed it closely for this forecast. Based on this, we will issue a Flash Flood Watch for the southern half of our forecast area. We are forecasting a storm total of 2 to 4 inches in this region, but isolated amounts could reach 8 inches. The bulk of this rain will occur today and tonight. The 0-1 km vertical bulk shear and SBCAPE will be sufficient for relatively shallow, "mini-supercells" over the Gulf coastal waters today, capable of producing damaging wind gusts and even isolated, brief tornadoes. This threat will gradually spread to the coast and just inland, but storms will likely become elevated in GA and AL, where the threat is lower. .Short Term [Tonight Through Wednesday]... The upper low near the northwest Gulf Coast will begin to move east and open up during this period. The approaching surface low that has garnered so much attention should lift northeast across the FL Panhandle coast somewhere between Apalachicola and Pensacola Tuesday morning. Categorical PoPs and areas of heavy rain will continue through much of the night along with the flash flood threat, particularly if we can get a north-south oriented band to set up. The low will then further weaken as it tracks northeast across the forecast area on Tuesday. This should end the flood threat. A cold front will approach from the northwest on Wednesday maintaining PoPs across the region, albeit lower than what we will see in the near term. .Long Term [Wednesday Night Through Monday]... A long wave trough will remain over the Southeast through the end of the work week and then pivot off to the northeast for the weekend. The front will also finally push through the area by that time setting us up for a classic October weekend, weather wise. Look for negligible PoPs from Friday night onward with max temps in the upper 70s to lower 80s and mins in the lower 60s. && .Aviation... [Through 06Z Tuesday] GFS/NAM MOS continue to maintain IFR or lower cigs through the period, while the HRRR and other high-resolution NWP guidance have mainly MVFR levels. Our forecast is a compromise, with predominantly low-end MVFR cigs (1-2k ft AGL) through the period. Periods of light to moderate RA are expected at all terminals, beginning at KECP early, eventually reaching KABY and KVLD later this afternoon. Brief periods of heavy rain with IFR vis/cigs as well as TSRA are also expected through tonight. && .Marine... We are still not quite getting into solid advisory conditions and we will let the exercise caution headline take care of things for the time being. Obviously if the approaching low gets stronger than anticipated, advisories will become necessary. && .Fire Weather... Wet flag conditions are likely through Tuesday, making controlled burns nearly impossible. && .Hydrology... For a QPF discussion, reference the near-term section above. With the heaviest amounts predicted nearer to the coast, area rivers will be able to handle this event without reaching flood stage given the recent dry conditions. With current streamflows, we`d need several inches of rain to get into the upper portions of many of the larger rivers and streams to produce river flooding, which still do not anticipate during this particular event. && .Preliminary Point Temps/PoPs... Tallahassee 82 74 86 73 88 / 80 80 60 30 40 Panama City 81 75 83 75 85 / 100 80 50 30 40 Dothan 78 70 82 69 85 / 80 80 60 40 50 Albany 81 72 83 71 85 / 80 80 70 40 50 Valdosta 83 72 84 72 85 / 70 70 70 30 40 Cross City 85 74 85 75 86 / 80 70 70 30 40 Apalachicola 81 73 84 72 85 / 100 80 50 30 40 && .TAE WATCHES/WARNINGS/ADVISORIES... FL...FLASH FLOOD WATCH through Tuesday morning FOR Calhoun-Central Walton-Coastal Bay-Coastal Dixie-Coastal Franklin-Coastal Gulf-Coastal Jefferson-Coastal Taylor-Coastal Wakulla- Gadsden-Holmes-Inland Bay-Inland Dixie-Inland Franklin- Inland Gulf-Inland Jefferson-Inland Taylor-Inland Wakulla- Jackson-Lafayette-Leon-Liberty-Madison-North Walton-South Walton-Washington. GA...FLASH FLOOD WATCH through Tuesday morning FOR Brooks-Decatur- Grady-Lowndes-Seminole-Thomas. AL...FLASH FLOOD WATCH through Tuesday morning FOR Geneva-Houston. GM...NONE. && $$ NEAR TERM...FOURNIER SHORT TERM...WOOL LONG TERM...WOOL AVIATION...FOURNIER MARINE...WOOL FIRE WEATHER...WOOL HYDROLOGY...GODSEY
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1151 PM CDT SUN SEP 27 2015 .UPDATE... ISSUED AT 900 PM CDT SUN SEP 27 2015 Still a lot of clouds over the area but see some breaks in the east. Not enough breaks to make me want to change the sky cover forecast as still expecting mostly cloudy skies. If skies become more partly cloudy later, then will have to update then...just not yet. Overall forecast looks good this evening and see no reason to update at this time. && .SHORT TERM...(TONIGHT) ISSUED AT 246 PM CDT SUN SEP 27 2015 Cloud cover remains fairly extensive across the area today, with the earlier breaks near the I-74 corridor quickly filling in late morning with diurnal cumulus. A few showers have been tracking northwest out of southern Illinois, associated with what is left of the upper low over the Tennessee Valley. Forecast soundings not really showing much in the way of clearing this evening, with skies mainly partly to mostly cloudy. A feature of interest is overnight, with the last few runs of the RAP showing a surge of stratus advecting northeast into our area after midnight and covering most of the state, along with some dense fog late in the night. The latest NAM model favors more of a patchy fog scenario, which would seem more likely given the lack of widespread clearing plus not much of a wind field to advect the low clouds into this area, so will continue with mention of patchy fog for now. .LONG TERM...(Monday THROUGH Sunday) ISSUED AT 246 PM CDT SUN SEP 27 2015 While by no means certain at this point, a bit more clarity has started to develop in the forecast for the remainder of the week. Above normal temperatures are expected to linger for a couple more days, then trend toward normal in the wake of Tuesday`s cold front, with below normal temperatures possible by the weekend as some degree of upper troffing develops across eastern North America. The model consensus has also trended back toward a drier solution for the week, with the best chances of rainfall occurring in the vicinity of the frontal passage on Tuesday. Maintained a very low chance for rainfall on Monday as weak disturbances track northeast up the Ohio River Valley from the Gulf of Mexico. However, the very modest forcing and instability support little more than we are currently seeing across southern Illinois today as far as coverage and intensity. A cold front, currently extending from northern Ontario into the central Plains, will sink southeast across the forecast area later Monday night into Tuesday. This front will not have much going for it as far as support for precipitation production. The best forcing will remain across Canada with the faster upper-level flow, with the best moisture bottled up with a system along the Gulf coast. So, plan to keep PoPs on the low side with fropa, and it is entirely possible that most locations will remain dry. However, this appears to be our best shot for widespread rainfall this week. A Canadian surface high builds into the area behind the cold front, which should help shave several degrees of the daily max/min temperatures. Aloft, the flow across North America is expected to transition from mostly zonal to more of a troffy pattern. However, exactly how the upper pattern will look by late week and how we`ll get there is still very much up for debate. Model spread remain significant, with the spaghetti plots looking much like a pile of spaghetti. There does not appear to be a strong signal for rainfall at any one time, although there is some consensus that it is possible over the weekend. Expect the weekend to be more dry than not, but there will certainly be some risk of rain. We`ll have to see how the models eventually resolve the coming pattern shift to pin point the threat better. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z Monday NIGHT) ISSUED AT 1151 PM CDT SUN SEP 27 2015 Still plenty of clouds around the area this evening and am expecting them to continue overnight. Some breaks in the east and northeast, but am expecting them to be filled in next couple of hours after TAF issuance time. HiRes models continue to show lower MVFR clouds and an increase in fog across the area, and this seems somewhat reasonable given we had some light showers move across the area earlier this evening. Guidance also gives IFR clouds during early morning hours and since winds are lighter and we have had some breaks in the clouds, dewpoints have come up so believe this is possible. So will have MVFR cigs with some light fog later tonight and add a TEMPO group for a few hours during the morning with cigs below 1kft and vis below 2sm. Things should improve during the later morning with VFR cigs around 4kft. Then during the evening, expecting lower clouds to dissipate and just have cirrus clouds. Winds will be southeast and then become south to southwest tomorrow...then light and variable tomorrow evening. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...Auten SHORT TERM...Geelhart LONG TERM...Bak AVIATION...Auten
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
420 AM EDT MON SEP 28 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 419 AM EDT MON SEP 28 2015 00Z RAOBS/LATEST WV IMAGERY AND RAP ANALYSIS SHOW ZONAL FLOW ALONG THE CNDN BORDER AS RATHER SHEARED SHRTWV STRETCHING FM THE NRN PLAINS INTO NW ONTARIO HAS WEAKENED THE UPR RDG THAT HAS BEEN SO PERSISTENT RECENTLY OVER ERN NAMERICA. THIS SHRTWV IS SUPPORTING A SFC COLD FNT THAT IS MOVING E THRU WRN LK SUP EARLY THIS MRNG. SINCE THIS DISTURBANCE IS SHEARED OUT AND THE MSTR INFLOW IN THE SW FLOW AHEAD OF THE FNT IS RATHER MODEST...SHOWER COVERAGE AHEAD OF THE INCOMING FNT IS RATHER LIMITED...WITH SCT COVERAGE LIMITED BY THE HIER STABILITY/DRY MID LVLS SHOWN ON THE 00Z MPX RAOB. CLDS IN ADVANCE OF THE FNT ARE PUSHING THRU THE WRN CWA...BUT THERE IS AN AXIS OF MOCLR SKIES OVER THE CENTRAL TO W OF SOME LO CLDS ACRS THE SE HALF OF THE CWA ASSOCIATED WITH LLVL MSTR SHOWN ON THE 00Z GRB/APX RAOBS. STEADY SW WINDS IN THE WARM SECTOR ARE KEEPING TEMPS WELL ABOVE NORMAL NOT FAR FM 60 EVEN WHERE THE SKY IS MOCLR. LOOKING FARTHER TO THE W...THE 00Z ABERDEEN SDAKOTA ROAB SHOWS A VERY DRY AIRMASS IS UNDER SFC HI PRES RDG TRAILING THE SFC COLD FNT. BUT FARTHER TO THE W...THERE IS AN AREA OF COLDER CLD TOPS/SHOWERS/EVEN SOME LTG STRIKES MOVING THRU THE NRN PLAINS. MODELS SHOW AREA OF UPR DVGC/MID LVL FGEN IN RRQ OF 100KT H3 JET MAX SUPPORTING THE NW ONTARIO SHRTWV IS OVER THIS AREA OF COLDER CLD TOPS. ANOTHER SHRTWV IS DIGGING THRU SCENTRAL CANADA AND DEEPENING AN UPR TROF THERE. MAIN FCST CONCERNS IN THE SHORT TERM FOCUS ON POPS ASSOCIATED WITH COLD FNT THAT WL BE CROSSING UPR MI TODAY. TODAY...LATEST SHORT TERM GUIDANCE IS IN GOOD AGREEMENT SHOWING SFC COLD FNT CROSSING UPR MI TODAY AND REACHING LK MI ARND 21Z. SINCE UPR DVGC/AXIS OF MID LVL FGEN SUPPORTING AREA OF DISTURBED WX IN THE NRN PLAINS IS FCST TO MOVE OVER THE UPR LKS WHILE THE FNT IS CROSSING THE CWA...MOST OF THE MODELS SHOW SHOWER COVERAGE EXPANDING WITH TIME. SINCE THE DRY AIR SHOWN ON THE ABERDEEN RAOB AND TRAILING THE FNT IS MOST LIKELY TO IMPACT THE WRN CWA BEFORE THE ARRIVAL...WL FCST THE HIEST LIKELY POPS OVER THE SE HALF OF UPR MI THIS AFTN. ALTHOUGH THERE HAVE BEEN SOME LTG STRIKES OBSVD UPSTREAM...MODEL FCST MUCAPES NO HIER THAN ABOUT 100 J/KG OVER THE CWA SUPPORT LEAVING TS OUT OF THE FCST FOR NOW. WITH EARLIER COLD FROPA OVER THE W...TEMPS THERE WL BE MUCH LOWER THAN YDAY. TNGT...MODELS DIFFER ON HOW QUICKLY THE SHOWERS EXIT THE SE CWA THIS EVNG. THE 00Z NAM IS QUITE A BIT SLOWER THAN THE REST OF THE GUIDANCE...BUT FAVOR THE FASTER DRYING TREND SHOWN BY THE MAJORITY OF THE OTHER MODELS GIVEN DRYNESS OF THE TRAILING AIRMASS DEPICTED ON THE 00Z ABERDEEN RAOB. THESE MODELS FAVOR SOME LINGERING HIER LIKELY POPS EARLY IN THE EVNG OVER THE SE BEFORE VIGOROUS DRYING BRINGS A CLRG TREND EVEN THOUGH ANOTHER COLD FNT ASSOCIATED WITH SHRTWV NOW DIGGING THRU SCENTRAL CANADA IS PROGGED TO PASS OVERNGT. H85 TEMPS DROPPING TO ARND 0C OVER THE KEWEENAW BY 12Z TUE WL RESULT IN A MUCH COOLER OVERNGT WITH MIN TEMPS DIPPING TO ARND 40 AND PERHAPS THE UPR 30S AT SOME OF THE HIER TERRAIN LOCATIONS. STRONG NW FLOW OVER THE RELATIVELY WARM LK WATERS WL LIMIT THE TEMP DROP. ALTHOUGH THE SFC-H85 DELTA T BTWN THE RELATIVELY WARM LK WATERS /MID TO UPR 50S F/IS SUFFICIENT FOR LK CLDS/PCPN...THE INCOMING AIRMASS WL BE TOO DRY AND THE LLVL FLOW TOO ACYC TO SUPPORT MORE THAN SCT CLDS OVER THE HIER TERRAIN. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 409 AM EDT MON SEP 28 2015 UPPER LEVEL TROUGH FROM HUDSON BAY TO UPPER GREAT LAKES SLIDES TO EASTERN CANADA LATE THIS WEEK WHILE HEIGHTS SLOWLY REBOUND FM NORTHERN PLAINS TO UPPER GREAT LAKES. TROUGH WILL ENSURE A COOLER WEEK WITH FROST/FREEZE OVER PARTS OF CWA TUE NIGHT AND MAYBE WED NIGHT AS WELL. ON TUESDAY...COOLER AIR ARRIVES WITH H85 TEMPS DOWN TO 0C TO -1C BY AFTN. NORTHWEST WINDS COULD BE GUSTY UP TO 25 MPH...ESPECIALLY CLOSER TO LK SUPERIOR. THOUGH APPROACHING HIGH IS THE DOMINANT FACTOR...NAM/GFS/GEM-REGIONAL INDICATE HIGHER H85 RH MOVING ACROSS LK SUPERIOR BY 12Z AND EXPANDING BY 18Z AS THE COOLER AIR ARRIVES. ENVISION FEW-SCT STRATOCU CLOUDS EXPANDING INTO A STRATOCU/CUMULUS DECK MAINLY CNTRL CWA BY AFTN...THEN DIMINISHING THROUGH THE REST OF AFTN. WITH THE CLOUDS AND COLD AIR ADVECTION...TEMPS WILL ONLY REACH LOW TO MID 50S NEAR LK SUPERIOR AND MAY TOUCH 60 DEGREES IN THE FAR SCNTRL. EVEN THOUGH SWIM RISK WILL BE HIGH ALONG MARQUETTE AND ALGER COUNTIES...AIR TEMPERATURES BELOW 55 DEGREES WILL PROHIBIT THE ISSUANCE OF A BEACH HAZARDS STATEMENT. NEXT UP IS TUE NIGHT AND THE FROST/FREEZE POTENTIAL. UPSHOT IS THE FROST/FREEZE POTENTIAL...AT LEAST AWAY FM THE INTERIOR WEST...IS NOT AS CLEAR CUT AS IT LOOKED THE LAST FEW DAYS. RECENTLY IN THE MODELS...IT APPEARED THAT THE APPROACHING HIGH WOULD SETTLE RIGHT OVERHEAD TUESDAY NIGHT. NOW...RIDGE AXIS STAYS MAINLY OVER WESTERN UPR MICHIGAN WHILE A LIGHT BUT PERSISTENT NE LOW-LEVEL FLOW AFFECTS EAST HALF OF CWA /SEE THIS AS 950-900MB WINDS OVER 10 KTS FM NCNTRL INTO EASTERN CWA. ALSO...WITH H85 TEMPS STAYING AROUND -1C OVERNIGHT TUESDAY NIGHT AND MORE OF AN ONSHORE WIND WITH SOME 875MB-850MB MOISTURE SHOWN ON GFS/NAM SOUNDINGS...MAY HAVE TO CONTEND WITH SCT- BKN LAKE EFFECT CLOUDS AS DELTA T VALUES WILL BE OVER 15C. BEST CHANCE FOR BKN CLOUDS WOULD BE OVER FAR NCNTRL UPR MICHIGAN AND ACROSS THE KEWEENAW. ADJUSTED SKY GRIDS TO BUMP UP CLOUD COVER FOR THERE AREAS...ESPECIALLY FOR THE KEWEENAW. FOR TEMPS...USED GUIDANCE THAT SHOWED LOWEST TEMPS IN THE UPR 20S OVER INTERIOR WEST BUT KEPT READINGS MAINLY MID-UPR 30S WHERE CLOUDS MAY DISRUPT COOLING. AFTER A MOSTLY SUNNY BUT COOL DAY ON WED...ANOTHER CHILLY NIGHT WITH SOME FROST SEEMS PROBABLE FOR WED NIGHT. SETUP IS NO BETTER THAN TUE NIGHT THOUGH AS HIGH CENTER IS MORE OVER QUEBEC AND THAT LEAVES A LIGHT EASTERLY FLOW ACROSS UPR MICHIGAN. EVEN SO...MIN TEMPS MAY BE AT LEAST IN LOWER 30S...ESPECIALLY OVER INLAND AREAS. DAYTIME HIGHS WED INTO THU SHOULD STAY IN THE 50S TO AROUND 60 DEGREES. THESE VALUES ARE PRETTY SEASONABLE FOR LATE SEPTEMBER...THOUGH MUCH COOLER THAN THE WELL ABOVE NORMAL TEMPS SEEN MUCH OF THIS MONTH. AFTER SOME RAIN TODAY...DRIER TREND THAT BEGAN TO SHOW UP IN THE MODELS LAST COUPLE DAYS CONTINUES AS HIGH PRESSURE BUILDING IN BEHIND COLD FRONTAL PASSAGE TODAY EXPANDS ACROSS THE UPPER GREAT LAKES ON WED AND BUILDS FURTHER TO OVER 1040MB IN QUEBEC ON FRIDAY. RIDGE FM THE HIGH EXPANDS WESTWARD ACROSS THE UPPER GREAT LAKES AND AS FAR WEST AS SASKATCHEWAN AND MANITOBA. AT FIRST GLANCE...THIS SHOULD KEEP MAJORITY OF REGION DRY THROUGH THE UPCOMING WEEKEND. HOWEVER...GFS AND 12Z ECMWF INDICATE THAT DECENT STRENGTH SHORTWAVE TROUGH BREAKING FREE FM THE LARGER SCALE TROUGH OVER EASTERN CANADA WILL SLIDE OVER UPR GREAT LAKES FRIDAY INTO THE WEEKEND. 00Z ECMWF NOT NEAR AS DEEP WITH TROUGH AS IT SHOWED WITH 12Z RUN THOUGH. DEEP MOISTURE APPEARS SPOTTY BUT THERE ARE HINTS THERE MAY BE ENOUGH FORCING AND MOISTURE TO SUPPORT SOME SHOWERS. OVERALL MOST CWA WILL REMAIN DRY THROUGH NEXT WEEKEND AS UPPER LEVEL TROUGH WILL BE LACKING LOW-LEVEL SUPPORT AS THE SFC HIGH REMAINS THE DOMINANT WEATHER FEATURE. IF THERE ENDS UP BEING BETTER CYCLONIC FLOW IN LOW- LEVELS AS 12Z ECMWF INDICATED...COULD SEE HELP FM LK SUPERIOR FOR PRECIP AS H85 TEMPS ARE FORECAST TO BE AS LOW AS -3C WITH THE UPPER TROUGH OVERHEAD. DAYTIME HIGHS SHOULD SETTLE BACK INTO THE 50S FRIDAY AND SATURDAY WITH THE COOLER TEMPS ALOFT. FINALLY...GFS IS MUCH MORE AGGRESSIVE THAN ECMWF WITH SECONDARY STRONGER SHORTWAVE TROUGH MOVING THROUGH IN MORE TYPICAL NW TO SE PROGRESSION LATE NEXT WEEKEND INTO EARLY NEXT WEEK /DAYS 8-10/. H85 TEMPS AS LOW AS -9C IN THE CORE OF THE COLDEST AIR OVER ONTARIO WITH AROUND -5C OVER UPR MICHIGAN LAST TWO RUNS. NEITHER THE 12Z RUN OR MOST RECENT 00Z RUN OF ECMWF SHOWED ADDITIONAL TROUGHING THOUGH WITH RIDGING RE APPEARING INTO NEXT WEEK IN WAKE OF THE WEEKEND TROUGHING. ECMWF DOES INDICATE TROUGHING AND SIMILAR DEGREE OF COLD AIR...BUT IT STAYS WELL UPSTREAM OVER NORTHWEST CANADA MOST OF THE WEEK. FOR THE FORECAST...CONSENSUS SHOULD COVER IT ATTM. USUALLY DO NOT GET TOO CONCERNED WITH THESE TYPE OF DETAILS IN THE FAR REACHES OF EXTENDED AND BEYOND...BUT GIVEN THE VERY WARM SEPTEMBER ABOUT TO CONCLUDE /POTENTIALLY RECORD WARMEST AT SOME LOCATIONS ACROSS UPR MICHIGAN/...IT IS NOTABLE THAT SOME MODELS ARE HINTING AT COOLER AIRMASSES CLOSE BY AS FIRST FULL WEEK OF OCTOBER ARRIVES. OFFICIAL 8-14 DAY AND EXPERIMENTAL 3-4 WEEK FORECASTS FM CPC STILL INDICATING WARMER THAN NORMAL TEMPERATURES SHOULD PREVAIL OVERALL THROUGH MUCH OF NEXT MONTH. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 1150 PM EDT SUN SEP 27 2015 VFR CONDITIONS WILL GRADUALLY GIVE WAY TO MVFR CIGS AND SCATTERED SHOWERS LATE TONIGHT INTO EARLY MONDAY MORNING AND LATE MON MORNING AT KSAW ALONG/AHEAD OF AN ADVANCING COLD FRONT. SHOWERS WILL ONLY LAST A FEW HOURS AT EACH TERMINAL WITH IMPROVING CONDITIONS FROM THE WEST THROUGH THE DAY ON MONDAY AS NW WINDS BRING DRIER AIR INTO THE REGION. LLWS IS EXPECTED AT ALL SITES THROUGH AT LEAST 12Z MON. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 419 AM EDT MON SEP 28 2015 SW WINDS UP TO 25 KTS THIS MRNG AHEAD OF A COLD FRONT MOVING THRU WESTERN LAKE SUPERIOR EARLY THIS MORNING WILL SHIFT TO THE W-NW UP TO 20 KTS FOLLOWING THE FRONTAL PASSAGE BY EARLY AFTERNOON OVER THE FAR EAST. ANOTHER COLD FRONT WILL SWING ACROSS THE LAKE TONIGHT. EXPECT NNW WINDS TO INCREASE UP TO 25-30 KTS IN ITS WAKE LATE TONIGHT/TUE. AS A TRAILING HIGH PRESSURE CLOSES IN ON THE AREA ON TUE NIGHT/WED...WINDS WILL DIMINISH TO UNDER 15-20 KTS. ONCE THE HIGH SHIFTS INTO QUEBEC LATER IN THE WEEK...E WINDS UP TO 20 KTS WILL DOMINATE. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...KC LONG TERM...JLA AVIATION...VOSS MARINE...KC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
410 AM EDT MON SEP 28 2015 .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 412 PM EDT SUN SEP 27 2015 WATER VAPOR IMAGERY AND RAP ANALYSIS SHOW A MID/UPPER RIDGE EXTENDING FROM THE DESERT SW TO SE CANADA WHILE A TROF IS PROGRESSING THRU WRN CANADA. AT THE SFC...THE TROF IS SUPPORTING A COLD FRONT EXTENDING FROM CNTRL SD ACROSS FAR NW MN TO HUDSON BAY. SW FLOW BTWN THE COLD FRONT AND SFC HIGH PRES CENTERED JUST OFF THE NEW ENGLAND COAST HAS LED TO ANOTHER UNSEASONABLY WARM LATE SEPT DAY TODAY. TEMPS ARE CURRENTLY WELL INTO THE 70S ACROSS MOST OF UPPER MI WITH A FEW LOCATIONS...MAINLY IN THE DOWNSLOPE AREAS NEAR LAKE SUPERIOR...AROUND 80F. FOG/STRATUS THAT WAS OVER CNTRL UPPER MI EARLY THIS MORNING BURNED OFF BY LATE MORNING. STRATOCU THAT WAS OVER IL/SE WI/LAKE MI EARLY TODAY HAS SPREAD N. WHILE STILL S OF KMNM...THE AREA OF MOISTURE HAS LED TO MORE CLOUD COVER FROM AROUND KISQ/KERY EASTWARD. OTHERWISE...SKIES ARE MOSTLY SUNNY. DURING THE SHORT TERM...FOCUS WILL BE ON CLOUD TRENDS THIS EVENING FOR VIEWING LUNAR ECLIPSE AND THEN PCPN POTENTIAL AS WRN CANADA TROF CONTINUES EASTWARD...PUSHING SFC COLD FRONT ACROSS THE AREA MON. WITH COLD FRONT APPROACHING...MODELS SHOW WINDS IN THE APPROACHING CLOUD BEARING LAYER (ROUGHLY 875-850MB) VEERING SOME TONIGHT. THUS...THE DIRECTION OF MOVEMENT OF THE STRATOCU APPROACHING FROM S SHOULD TEND TO TAKE ON MORE OF AN EASTERLY COMPONENT WITH TIME. AT THIS POINT...IT APPEARS LOCATIONS ROUGHLY EAST OF AN IRON MTN TO MUNISING LINE WILL HAVE THE MOST CLOUD COVER...POTENTIALLY OBSCURING MUCH OF THE LUNAR ECLIPSE THIS EVENING AT A FEW LOCATIONS. NAM IN PARTICULAR IS AGGRESSIVE IN MOISTENING LOWER LEVELS BLO STRATOCU LAYER FARTHER TO THE W...BUT DON`T THINK THIS WILL TRANSLATE TO LOW CLOUD DEVELOPMENT THIS EVENING EVEN IF IT IS CORRECT WITH THE MOISTURE. ATTENTION THEN TURNS TO APPROACHING COLD FRONT. THERE ARE ONLY VERY MINOR DIFFERENCES IN THE MODELS IN TIMING FRONT ACROSS THE AREA... REACHING THE W EARLY MON MORNING AND EXITING THE SE LATE AFTN. GUIDANCE SUPPORTS SCT/CHC POPS LATE TONIGHT OVER THE W. BIGGER UNCERTAINTY CONTINUES TO BE WHETHER THE UPPER JET CONFIGURATION WITH RIGHT ENTRANCE UPPER DIVERGENCE AND LOW/MID LEVEL FGEN UNDERNEATH WILL BE SUFFICENT TO HELP DEVELOP A HEAVIER/MORE SOLID BAND OF SHRA JUST BEHIND THE FRONT AS IT MOVES SE ACROSS THE AREA MON. THE MAJORITY OF GUIDANCE SUPPORTS THE IDEA OF IMPROVED FORCING LEADING TO AN INCREASE IN SHRA COVERAGE ACROSS AT LEAST THE SCNTRL AND ERN FCST AREA MON AFTN. WITH THE LAST FEW HRS OF THE LATEST RAP RUN ENDING AT 12Z MON APPEARING TO SUPPORT THAT IDEA AS IT HAS STRONGER FORCING DEVELOPING TO THE W AT THE END OF THE MODEL RUN...WILL RAISE POPS FOR MON...ESPECIALLY SCNTRL AND E WHERE LIKELY/NMRS WILL BE UTILIZED LATE. NOT OUT OF THE QUESTION THAT THERE COULD BE A FEW RUMBLES OF THUNDER...BUT POTENTIAL IS TOO LOW AT THIS POINT TO INCLUDE MENTION. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 409 AM EDT MON SEP 28 2015 UPPER LEVEL TROUGH FROM HUDSON BAY TO UPPER GREAT LAKES SLIDES TO EASTERN CANADA LATE THIS WEEK WHILE HEIGHTS SLOWLY REBOUND FM NORTHERN PLAINS TO UPPER GREAT LAKES. TROUGH WILL ENSURE A COOLER WEEK WITH FROST/FREEZE OVER PARTS OF CWA TUE NIGHT AND MAYBE WED NIGHT AS WELL. ON TUESDAY...COOLER AIR ARRIVES WITH H85 TEMPS DOWN TO 0C TO -1C BY AFTN. NORTHWEST WINDS COULD BE GUSTY UP TO 25 MPH...ESPECIALLY CLOSER TO LK SUPERIOR. THOUGH APPROACHING HIGH IS THE DOMINANT FACTOR...NAM/GFS/GEM-REGIONAL INDICATE HIGHER H85 RH MOVING ACROSS LK SUPERIOR BY 12Z AND EXPANDING BY 18Z AS THE COOLER AIR ARRIVES. ENVISION FEW-SCT STRATOCU CLOUDS EXPANDING INTO A STRATOCU/CUMULUS DECK MAINLY CNTRL CWA BY AFTN...THEN DIMINISHING THROUGH THE REST OF AFTN. WITH THE CLOUDS AND COLD AIR ADVECTION...TEMPS WILL ONLY REACH LOW TO MID 50S NEAR LK SUPERIOR AND MAY TOUCH 60 DEGREES IN THE FAR SCNTRL. EVEN THOUGH SWIM RISK WILL BE HIGH ALONG MARQUETTE AND ALGER COUNTIES...AIR TEMPERATURES BELOW 55 DEGREES WILL PROHIBIT THE ISSUANCE OF A BEACH HAZARDS STATEMENT. NEXT UP IS TUE NIGHT AND THE FROST/FREEZE POTENTIAL. UPSHOT IS THE FROST/FREEZE POTENTIAL...AT LEAST AWAY FM THE INTERIOR WEST...IS NOT AS CLEAR CUT AS IT LOOKED THE LAST FEW DAYS. RECENTLY IN THE MODELS...IT APPEARED THAT THE APPROACHING HIGH WOULD SETTLE RIGHT OVERHEAD TUESDAY NIGHT. NOW...RIDGE AXIS STAYS MAINLY OVER WESTERN UPR MICHIGAN WHILE A LIGHT BUT PERSISTENT NE LOW-LEVEL FLOW AFFECTS EAST HALF OF CWA /SEE THIS AS 950-900MB WINDS OVER 10 KTS FM NCNTRL INTO EASTERN CWA. ALSO...WITH H85 TEMPS STAYING AROUND -1C OVERNIGHT TUESDAY NIGHT AND MORE OF AN ONSHORE WIND WITH SOME 875MB-850MB MOISTURE SHOWN ON GFS/NAM SOUNDINGS...MAY HAVE TO CONTEND WITH SCT- BKN LAKE EFFECT CLOUDS AS DELTA T VALUES WILL BE OVER 15C. BEST CHANCE FOR BKN CLOUDS WOULD BE OVER FAR NCNTRL UPR MICHIGAN AND ACROSS THE KEWEENAW. ADJUSTED SKY GRIDS TO BUMP UP CLOUD COVER FOR THERE AREAS...ESPECIALLY FOR THE KEWEENAW. FOR TEMPS...USED GUIDANCE THAT SHOWED LOWEST TEMPS IN THE UPR 20S OVER INTERIOR WEST BUT KEPT READINGS MAINLY MID-UPR 30S WHERE CLOUDS MAY DISRUPT COOLING. AFTER A MOSTLY SUNNY BUT COOL DAY ON WED...ANOTHER CHILLY NIGHT WITH SOME FROST SEEMS PROBABLE FOR WED NIGHT. SETUP IS NO BETTER THAN TUE NIGHT THOUGH AS HIGH CENTER IS MORE OVER QUEBEC AND THAT LEAVES A LIGHT EASTERLY FLOW ACROSS UPR MICHIGAN. EVEN SO...MIN TEMPS MAY BE AT LEAST IN LOWER 30S...ESPECIALLY OVER INLAND AREAS. DAYTIME HIGHS WED INTO THU SHOULD STAY IN THE 50S TO AROUND 60 DEGREES. THESE VALUES ARE PRETTY SEASONABLE FOR LATE SEPTEMBER...THOUGH MUCH COOLER THAN THE WELL ABOVE NORMAL TEMPS SEEN MUCH OF THIS MONTH. AFTER SOME RAIN TODAY...DRIER TREND THAT BEGAN TO SHOW UP IN THE MODELS LAST COUPLE DAYS CONTINUES AS HIGH PRESSURE BUILDING IN BEHIND COLD FRONTAL PASSAGE TODAY EXPANDS ACROSS THE UPPER GREAT LAKES ON WED AND BUILDS FURTHER TO OVER 1040MB IN QUEBEC ON FRIDAY. RIDGE FM THE HIGH EXPANDS WESTWARD ACROSS THE UPPER GREAT LAKES AND AS FAR WEST AS SASKATCHEWAN AND MANITOBA. AT FIRST GLANCE...THIS SHOULD KEEP MAJORITY OF REGION DRY THROUGH THE UPCOMING WEEKEND. HOWEVER...GFS AND 12Z ECMWF INDICATE THAT DECENT STRENGTH SHORTWAVE TROUGH BREAKING FREE FM THE LARGER SCALE TROUGH OVER EASTERN CANADA WILL SLIDE OVER UPR GREAT LAKES FRIDAY INTO THE WEEKEND. 00Z ECMWF NOT NEAR AS DEEP WITH TROUGH AS IT SHOWED WITH 12Z RUN THOUGH. DEEP MOISTURE APPEARS SPOTTY BUT THERE ARE HINTS THERE MAY BE ENOUGH FORCING AND MOISTURE TO SUPPORT SOME SHOWERS. OVERALL MOST CWA WILL REMAIN DRY THROUGH NEXT WEEKEND AS UPPER LEVEL TROUGH WILL BE LACKING LOW-LEVEL SUPPORT AS THE SFC HIGH REMAINS THE DOMINANT WEATHER FEATURE. IF THERE ENDS UP BEING BETTER CYCLONIC FLOW IN LOW- LEVELS AS 12Z ECMWF INDICATED...COULD SEE HELP FM LK SUPERIOR FOR PRECIP AS H85 TEMPS ARE FORECAST TO BE AS LOW AS -3C WITH THE UPPER TROUGH OVERHEAD. DAYTIME HIGHS SHOULD SETTLE BACK INTO THE 50S FRIDAY AND SATURDAY WITH THE COOLER TEMPS ALOFT. FINALLY...GFS IS MUCH MORE AGGRESSIVE THAN ECMWF WITH SECONDARY STRONGER SHORTWAVE TROUGH MOVING THROUGH IN MORE TYPICAL NW TO SE PROGRESSION LATE NEXT WEEKEND INTO EARLY NEXT WEEK /DAYS 8-10/. H85 TEMPS AS LOW AS -9C IN THE CORE OF THE COLDEST AIR OVER ONTARIO WITH AROUND -5C OVER UPR MICHIGAN LAST TWO RUNS. NEITHER THE 12Z RUN OR MOST RECENT 00Z RUN OF ECMWF SHOWED ADDITIONAL TROUGHING THOUGH WITH RIDGING RE APPEARING INTO NEXT WEEK IN WAKE OF THE WEEKEND TROUGHING. ECMWF DOES INDICATE TROUGHING AND SIMILAR DEGREE OF COLD AIR...BUT IT STAYS WELL UPSTREAM OVER NORTHWEST CANADA MOST OF THE WEEK. FOR THE FORECAST...CONSENSUS SHOULD COVER IT ATTM. USUALLY DO NOT GET TOO CONCERNED WITH THESE TYPE OF DETAILS IN THE FAR REACHES OF EXTENDED AND BEYOND...BUT GIVEN THE VERY WARM SEPTEMBER ABOUT TO CONCLUDE /POTENTIALLY RECORD WARMEST AT SOME LOCATIONS ACROSS UPR MICHIGAN/...IT IS NOTABLE THAT SOME MODELS ARE HINTING AT COOLER AIRMASSES CLOSE BY AS FIRST FULL WEEK OF OCTOBER ARRIVES. OFFICIAL 8-14 DAY AND EXPERIMENTAL 3-4 WEEK FORECASTS FM CPC STILL INDICATING WARMER THAN NORMAL TEMPERATURES SHOULD PREVAIL OVERALL THROUGH MUCH OF NEXT MONTH. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 1150 PM EDT SUN SEP 27 2015 VFR CONDITIONS WILL GRADUALLY GIVE WAY TO MVFR CIGS AND SCATTERED SHOWERS LATE TONIGHT INTO EARLY MONDAY MORNING AND LATE MON MORNING AT KSAW ALONG/AHEAD OF AN ADVANCING COLD FRONT. SHOWERS WILL ONLY LAST A FEW HOURS AT EACH TERMINAL WITH IMPROVING CONDITIONS FROM THE WEST THROUGH THE DAY ON MONDAY AS NW WINDS BRING DRIER AIR INTO THE REGION. LLWS IS EXPECTED AT ALL SITES THROUGH AT LEAST 12Z MON. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 412 PM EDT SUN SEP 27 2015 AHEAD OF AN APPROACHING COLD FRONT...S TO SW WINDS ACROSS LAKE SUPERIOR WILL GUST TO AROUND 25KT TONIGHT...BUT UP TO 30KT AT THE HIGHEST OBS PLATFORMS. THE FRONT WILL CROSS LAKE SUPERIOR LATE TONIGHT AND MON...BRINGING A WIND SHIFT TO THE W TO NW WITH SPEEDS GENERALLY UNDER 20KT. AN UPTICK IN WINDS IS EXPECTED MON NIGHT/TUE TO 20-30KT...ESPECIALLY OVER CNTRL AND EASTERN LAKE SUPERIOR AS INSTABILITY INCREASES WITH INCREASINGLY COLDER AIR FLOWING OVER THE LAKE AHEAD OF APPROACHING HIGH PRES. WINDS WILL THEN DIMINISH TO UNDER 15KT W TO E TUE NIGHT AS HIGH PRES SETTLES OVER THE UPPER LAKES. THE HIGH PRES WILL THEN DRIFT TO THE ENE WED THRU FRI...BUT WILL MAINTAIN RIDGING BACK INTO THE UPPER LAKES. AS A RESULT...WHILE WINDS WILL INCREASE SOME...SPEEDS SHOULD REMAIN MOSTLY 20KT OR LESS DURING THE LAST HALF OF THE WEEK. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...ROLFSON LONG TERM...JLA AVIATION...VOSS MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS GAYLORD MI
233 AM EDT MON SEP 28 2015 .UPDATE... ISSUED AT 1011 PM EDT SUN SEP 27 2015 LOW CLOUDS (UNFORTUNATELY) CONTINUE TO HANG OVER ALMOST ALL OF OUR CWA LATE THIS EVENING...WITH THE EXCEPTION OF FAR WRN SECTIONS OF CHIPPEWA AND MACKINAC COUNTIES RIGHT ALONG THE NW EDGE OF THIS LOW CLOUD DECK. BAD TIMING TO HAVE A CLOUDY NIGHT GIVEN THE RARE SUPERMOON LUNAR ECLIPSE HAPPENING AS I WRITE. EXPECT THESE CLOUDS WILL REMAIN IN PLACE ALL NIGHT. A FEW REGION OBS HAVE ACTUALLY REPORTED SOME VERY LIGHT SHOWER ACTIVITY...AND HAVE ADDED THIS TO THE FORECAST FOR THE BALANCE OF THE NIGHT. BOTH THE LATEST RAP13 AND HRRR SUPPORT THIS NOTION. TEMPS WILL ONLY FALL A FEW DEGREES AS WE HEAD INTO THE OVERNIGHT HOURS...WITH LOW TEMPS COOLING INTO THE UPPER 50S AND LOWER 60S. && .NEAR TERM...(THIS EVENING THROUGH TONIGHT) ISSUED AT 414 PM EDT SUN SEP 27 2015 ...SORRY FOR THE CLOUDS LUNAR ECLIPSE VIEWERS... MID LEVEL MOISTURE CONTINUES TO STREAM NORTHWARD INTO NORTHERN MICHIGAN. THIS HAS RESULTED IN MOSTLY CLOUDY SKIES ACROSS THE REGION AS EXPECTED. HOWEVER THERE IS AT LEAST A LITTLE HOPE ON THE HORIZON AS SATELLITE IMAGERY DOES SHOW A FEW HOLES IN THE CLOUD COVER UPSTREAM. SO ALTHOUGH IT MAY BE TOUGH TO SEE THE LUNAR ECLIPSE...A FEW OCCASIONAL GLIMPSES ARE STILL POSSIBLE AT TIMES THIS EVENING...DESPITE THE ABUNDANT CLOUD COVER. THERE ARE QUESTIONS OVERNIGHT ABOUT THE EXTENT OF CLOUD COVER AS MOISTURE BEGINS TO DIMINISH (1000-500 MB RH FALLS FROM BETWEEN 60 AND 80 PERCENT TO BETWEEN 50 AND 70 PERCENT)...BUT ANY PARTIAL CLEARING WILL LIKELY LEAD TO AREAS OF STRATUS FORMATION. MILDER WITH SOUTH WINDS KEEPING LOWS IN THE UPPER 50S TO MIDDLE 60S. && .SHORT TERM...(MONDAY THROUGH WEDNESDAY) ISSUED AT 414 PM EDT SUN SEP 27 2015 ...HEADLINES.. HIGH IMPACT WEATHER POTENTIAL: NON-SEVERE CONVECTION MONDAY AFTERNOON/EVENING. FROST POSSIBLE WEDNESDAY MORNING. PATTERN SYNOPSIS/FORECAST: MAIN WESTERLIES DISPLACED WELL NORTH ACROSS CANADA...WITH WEAK UPPER LEVEL FLOW AND EMBEDDED DISTURBANCES ACROSS THE SOUTHERN/EASTERN CONTINENTAL U.S. NORTHERN PORTION OF A SPLITTING TROUGH CROSSING WESTERN/CENTRAL CANADA...WITH A PIECE OF ENERGY LEFT BEHIND AROUND 140W. MEANWHILE...DISTURBANCES CAUGHT IN WEAK FLOW INCLUDE ONE OVER TEXAS/WESTERN GULF OF MEXICO...A SUBTROPICAL DISTURBANCE SOUTH OF BERMUDA NEAR 60W...AND A WEAKENING FEATURE OVER THE MID ATLANTIC STATES. AT THE SURFACE...1034MB HIGH STRETCHING ACROSS NEW ENGLAND/NOVA SCOTIA RIDGING WEST INTO THE GREAT LAKES/OHIO VALLEY. PLENTY OF MOISTURE OVER THE SOUTHEAST QUADRANT OF THE COUNTRY...WITH 60S DEW POINTS/BOUNDARY LAYER MIXING RATIOS >10G/KG CREEPING AROUND THE PERIPHERY OF THE ANTICYCLONE AND INTO ILLINOIS/INDIANA/SOUTHWEST LOWER MICHIGAN. COLD FRONT EXTENDS FROM NORTHWEST ONTARIO INTO THE DAKOTAS/NORTHERN WYOMING. HEIGHT FALLS ASSOCIATED WITH THE SHORT WAVE TROUGH OVER WESTERN CANADA WILL HAVE THE BIGGEST SHORT TERM FORECAST IMPACT ON THE GREAT LAKES FOR THE EARLY PART OF THIS WEEK...AS SOUTHERN PORTION OF THIS WAVE WILL CLIP MICHIGAN IN THE MONDAY-TUESDAY TIME FRAME BEFORE LIFTING OUT BY MIDWEEK WITH THE POSSIBILITY OF ANOTHER WEAKNESS DEVELOPING OVER THE OHIO/TENNESSEE VALLEYS AND SOUTHEASTERN STATES BY THURSDAY. UPSTREAM COLD FRONT WILL ARRIVE ACROSS NORTHERN MICHIGAN MONDAY AFTERNOON...AND IS EXPECTED TO DROP INTO SOUTHERN LOWER MICHIGAN AFTER MIDNIGHT TUESDAY WITH DECENT COLD ADVECTION IN ITS WAKE. HIGH PRESSURE THEN BUILDS INTO MICHIGAN TUESDAY NIGHT/ WEDNESDAY. PRIMARY FORECAST CONCERNS: PRECIPITATION CHANCES/AMOUNTS WITH COLD FRONT MONDAY/MONDAY NIGHT...CHILLY TEMPERATURES WEDNESDAY MORNING? MONDAY...COLD FRONT NOT EXPECTED TO ARRIVE ACROSS EASTERN UPPER UNTIL MID AFTERNOON...BUT INCREASING LOW LEVEL MOISTURE AHEAD OF THE FRONT WITH DEW POINTS CLIMBING INTO THE LOWER-MID 60S. SOME INDICATIONS OF INSTABILITY DEVELOPING AHEAD OF THE FRONT ESPECIALLY IN THE NAM-WRF WHICH IS (AS USUAL) BULLISH ON PULLING HIGHER DEW POINTS INTO NORTHERN LOWER. THINK WHAT MAY OCCUR IS A MOSTLY POST- FRONTAL RAIN BAND MOVING INTO EASTERN UPPER DURING MID/LATE AFTERNOON...WHILE PRE-FRONTAL CONVECTION DEVELOPS ACROSS INTERIOR NORTHERN LOWER DURING THE AFTERNOON. POSSIBLE THAT FAR SOUTHWEST PORTIONS OF THE FORECAST AREA (MBL/FKS/TVC) MAY STAY DRY THROUGH THE AFTERNOON. ONE LAST WARM AFTERNOON EXPECTED WITH HIGHS IN THE 70S. RAIN BAND SHOULD THEN PROGRESS SOUTHWARD ACROSS NORTHERN MICHIGAN MONDAY NIGHT...AIDED BY RIGHT ENTRANCE REGION JET FORCING. RAIN SHOULD PUSH SOUTH OF THE UPPER PENINSULA DURING THE EARLY MORNING HOURS OF TUESDAY. GENERAL RAINFALL TOTALS OF 0.25-0.50 INCH EXPECTED THROUGH TUESDAY MORNING. TUESDAY...WILL BE FIRMLY IN POST-COLD FRONT AIR MASS TUESDAY MORNING...MOST OF THE PRECIPITATION SHOULD BE SOUTH OF THE FORECAST AREA BUT CAN`T RULE OUT SOME LINGERING SHOWERS ACROSS SOUTHEAST QUARTER OF THE FORECAST AREA ALLOWING FOR UNCERTAINTY IN FRONTAL SPEED. BUT SHOULD BE CLEARING OUT BEYOND THAT AS COOLER/DRIER AIR SPILL ACROSS NORTHERN MICHIGAN...AND MUCH COOLER THAN RECENT DAYS WITH HIGHS IN THE UPPER 50S-MID 60S EXPECTED WITH A NORTHWEST BREEZE. HIGH PRESSURE THEN BUILDS INTO MICHIGAN TUESDAY NIGHT ALONG WITH A FLATTENING PRESSURE GRADIENT. POSSIBILITY OF GOOD RADIATIONAL COOLING CONDITIONS MAY SET THE STAGE FOR A PRETTY GOOD FROST ACROSS INTERIOR EASTERN UPPER/NORTHERN LOWER MICHIGAN WEDNESDAY MORNING. WEDNESDAY...SURFACE HIGH PRESSURE WILL REMAIN IN CONTROL WEDNESDAY...SO ANOTHER NICE DAY ON TAP THOUGH TEMPERATURES WILL REMAIN A FEW DEGREES BELOW END OF SEPTEMBER NORMALS. && .LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY) ISSUED AT 414 PM EDT SUN SEP 27 2015 A FAIRLY QUIET EXTENDED PERIOD IS ON TAP ACROSS NORTHERN MICHIGAN AS SURFACE HIGH PRESSURE DOMINATES...PROVIDING DRY CONDITIONS AND COOLER TEMPERATURES THROUGH AT LEAST SATURDAY. RECENT TRENDS HAVE SLOWED NEXT WEEKEND`S DEVELOPMENT OF LOW PRESSURE OVER THE PLAINS BEFORE SLIDING NORTHEASTWARD TOWARD THE GREAT LAKES. AT THIS POINT...THERE`S FAIRLY LOW CONFIDENCE IN HOW THE DETAILS WILL PLAY OUT FOR THE END OF NEXT WEEKEND AS INTERACTIONS...FROM BOTH THE AFOREMENTIONED HIGH PRESSURE AND ANOTHER DEVELOPING LOW PRESSURE CENTER OVER THE EASTERN SEABOARD...REMAIN UNCLEAR. IT`S SAFE TO SAY THE AREA WILL RETURN TO TEMPERATURES MUCH MORE REPRESENTATIVE OF CLIMATOLOGICAL NORMAL FOR THE FIRST WEEK OF OCTOBER. HIGH TEMPS ARE EXPECTED TO RANGE FROM THE UPPER 50S TO LOWER 60S WITH LOWS IN THE 30S TO LOW 40S THROUGHOUT THE PERIOD. HAVE GONE AHEAD AND ADDED PATCHY FROST ON WEDNESDAY NIGHT FOR THE TYPICAL COOLER/INTERIOR SPOTS IN NORTHERN LOWER. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 233 AM EDT MON SEP 28 2015 LOW VFR/HIGH MVFR CIGS WILL PERSIST ACROSS NRN LOWER MICHIGAN OVERNIGHT AND THROUGH MUCH OF THE DAY MONDAY...ALTHOUGH THERE WILL BE BREAKS AT TIMES IN THE CLOUDS. DAYTIME HEATING ON MONDAY MIGHT BUBBLE UP A FEW SHOWERS/ISOLATED THUNDER ACROSS NE LOWER MICHIGAN IN THE AFTERNOON...RESULTING IN A LOWER END CHANCE FOR SHOWERS AT APN. BUT A SLOW MOVING COLD FRONT WILL SAG INTO THE REGION LATE MONDAY AFTERNOON/MONDAY NIGHT. EXPECT A QUICK LOWERING OF CLOUD COVER TO MVFR WITH THE FRONT AS COOLER AIR BLEEDS INTO THE REGION. HOWEVER...THERE WILL ALSO BE A NARROW BAND OF MORE WIDESPREAD RAINFALL DEVELOPING BEHIND THE FRONT THAT WILL SLOWLY FOLD INTO NRN LOWER MICHIGAN DURING THE COURSE OF THE NIGHT. WINDS...SW 10 KNOTS OR LESS OVERNIGHT THROUGH MONDAY WITH SOME LLWS OVERNIGHT. WINDS TURN INTO THE N/NW MONDAY EVENING WITH PASSAGE OF THE FRONT...WITH SOME GUSTINESS ANTICIPATED. && .MARINE... ISSUED AT 414 PM EDT SUN SEP 27 2015 A WEAK UPPER LEVEL SYSTEM FLOATING AROUND THE MID ATLANTIC WILL CONTINUE MOSTLY CLOUDY SKIES THROUGH TONIGHT. A COLD FRONT WITH STRENGTHENING SW WINDS AHEAD OF IT FOR TONIGHT INTO MONDAY MORNING WILL BRING SOME LOW END ADVISORY LEVEL WINDS WITH SMALL CRAFT ADVISORIES REMAINING POSTED. THE FRONT ARRIVES BY MONDAY EVENING...BRINGING AT LEAST SOME LIGHT RAIN THAT MAY LINGER INTO TUESDAY MORNING. NORTH NORTHWEST WINDS WILL LIKELY BECOME GUSTY TUESDAY WITH ANOTHER ROUND OF SMALL CRAFT ADVISORIES POSSIBLE. && .APX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LH...SMALL CRAFT ADVISORY UNTIL 11 AM EDT THIS MORNING FOR LHZ347>349. LM...SMALL CRAFT ADVISORY UNTIL 11 AM EDT THIS MORNING FOR LMZ341-342- 344>346. LS...NONE. && $$ UPDATE...MLR NEAR TERM...SULLIVAN SHORT TERM...JPB LONG TERM...GILLEN AVIATION...ADAM MARINE...SULLIVAN
AREA FORECAST DISCUSSION
NWS DULUTH MN
305 AM CDT MON SEP 28 2015 .SHORT TERM...(TODAY THROUGH TUESDAY) ISSUED AT 304 AM CDT MON SEP 28 2015 A WEAK COLD FRONT IS SLOWLY SLIDING SOUTHEAST ACROSS THE FORECAST AREA EARLY THIS MORNING...GENERALLY DRAPED FROM LAKE SUPERIOR SOUTHEAST ACROSS CENTRAL MINNESOTA AND ON INTO SOUTH DAKOTA. SOME SCATTERED SHOWERS ARE AFFECTING NORTHWEST WISCONSIN OUT AHEAD OF IT...BUT NOT BRINGING MUCH IN THE WAY OF PRECIPITATION. SOME FOG HAS FORMED BEHIND THE FRONT...BUT VISIBILITIES ARE STILL IN THE 3-5 MILE RANGE AND DO NOT EXPECT CONDITIONS TO GET MUCH WORSE. THE FRONT WILL CONTINUE TO SLIDE SOUTHEAST THIS MORNING...AND SHOULD BE SOUTHEAST OF THE FORECAST AREA BY MID DAY. OF INTEREST ON SATELLITE IMAGERY THIS MORNING IS A SHORTWAVE MOVING OUT OF WYOMING AND INTO SOUTH DAKOTA...WITH SOME DECENTLY COLD CLOUD TOPS AND A FAIR AMOUNT OF LIGHTNING WITH IT...SOMEWHAT UNUSUAL FOR THIS TIME OF YEAR AND DAY. THUS...EXPECT THAT THIS PARTICULAR FEATURES IS PROBABLY STRONGER THAN MOST OF THE MODELS SHOW...AND EXPECT IT TO CONTINUE TO RIPPLE EAST ALONG THE COLD FRONT DURING THE DAY TODAY. BASED ON THIS STRONGER FEATURE HAVE GONE WITH HIGHER POPS ACROSS MY SOUTHEASTERN CWA DURING THE DAY TODAY...USING THE 06Z HRRR RUN FOR THE GENERAL PLAN AND HAVE MADE SOME OTHER TWEAKS TO PLACE A BAND OF SHOWERS AND ISOLATED THUNDERSTORMS ACROSS MY NW WISCONSIN COUNTIES DURING THE DAYTIME TODAY...GENERALLY FROM 15Z TO 21Z. OTHERWISE...IT SHOULD BE A FAIRLY DECENT DAY WITH HIGHS IN THE 60S MOST LOCATIONS AND LIGHT WINDS. TONIGHT THE FRONT DROPS FAR ENOUGH SOUTH THAT THE RIDGE OF HIGH PRESSURE CAN BUILD INTO THE AREA FOR TONIGHT AND TUESDAY. THIS SHOULD SET US UP FOR A GOOD RADIATIONAL COOLING NIGHT WITH CLEAR OR NEARLY CLEAR SKIES AND COLD TEMPERATURES ALOFT TO ACCOMPANY THE COLD AIRMASS MOVING INTO THE AREA. LATEST GUIDANCE INDICATES THAT WE WILL HAVE SOME 850MB TEMPS IN THE -3 C RANGE BY 12Z. THIS SHOULD SET US UP FOR SOME CHILLY TEMPERATURES TONIGHT...WITH LOWS DIPPING INTO EVEN THE UPPER 20S IN SOME OF OUR COLD SPOTS AND 30S ELSEWHERE. FROST IS A REAL POSSIBILITY. HAVE LEFT IT TO THE DAY SHIFT TO SEND OUT A FROST/FREEZE ADVISORY AS SPECIFIC LOCATIONS ARE STILL SOMEWHAT IN QUESTION...BUT ANTICIPATE THAT WE WILL NEED ONE OR BOTH FOR AT LEAST PARTS OF THE FORECAST AREA. TUESDAY TO REMAIN CHILLY WITH HIGHS ONLY IN THE 50S IN THIS CHILLY AIRMASS...AND THE DRY AIR TO BRING OUR MIN RH VALUES DOWN INTO THE 20 PERCENT RANGE DURING THE AFTERNOON. .LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY) ISSUED AT 304 AM CDT MON SEP 28 2015 LOW CONFIDENCE IN THE PATTERN LATE WEEK INTO THE WEEKEND DUE TO A WIDE RANGE IN MODEL SOLUTIONS...BUT SOME NOTABLE TRENDS ARE BEGINNING TO EMERGE. A COOL TUESDAY NIGHT WITH TEMPERATURES FALLING TO NEAR FREEZING IN SOME LOCATIONS...THEN GENERALLY SEASONABLE TEMPERATURES WITH LOW CHANCES FOR PRECIPITATION THROUGH THE REST OF THE PERIOD. ON THE SYNOPTIC SCALE THE LONG TERM PERIOD BEGINS WITH AN AMPLIFIED RIDGE ACROSS THE INTERMOUNTAIN WEST AND BROAD TROUGH OVER THE SOUTHEAST. AN AREA OF HIGH PRESSURE WILL BE DRIFTING EASTWARD WITH WEST/SOUTHWEST FLOW AT LOW/MID LEVELS DEVELOPING ON WEDNESDAY. AS THIS HIGH DEPARTS TUESDAY NIGHT TEMPS ARE EXPECTED TO FALL TO NEAR FREEZING...MAINLY ACROSS INLAND NORTHWEST WISCONSIN BUT ALSO IN POCKETS ACROSS THE IRON RANGE AND MN ARROWHEAD. AN EMBEDDED SHORTWAVE TROUGH JUST AHEAD OF THE RIDGE AXIS WILL DIVE SOUTHWARD FROM SASKATCHEWAN/MANITOBA INTO THE NORTHERN PLAINS. WHILE THE BEST UPPER LEVEL FORCING WILL BE IN SOUTHERN MANITOBA...WITH WARM AIR ADVECTION AND A FAIRLY DEEP LAYER OF MOISTURE IN PLACE THERE IS A CHANCE FOR SHOWERS LATE WED/WED NIGHT ACROSS NORTHWEST TO EVEN NORTH CENTRAL MINNESOTA...WITH THE BEST CHANCE TOWARDS THE BORDERLAND. WHILE CLOUDS WILL BE PRESENT ACROSS MUCH OF NORTHERN MINNESOTA WEDNESDAY...THEY SHOULD BEGIN TO CLEAR OUT THURSDAY AS EASTERLY LOW LEVEL WINDS PREVAIL DUE TO AN 850/700 MB HIGH OVER ONTARIO. FOR THE WEEKEND GUIDANCE IS ALL OVER THE PLACE WITH THE SYNOPTIC PATTERN...EVEN DISREGARDING THE CANADIAN MODEL WHICH HAS RECENTLY SHOWN POOR RUN TO RUN CONTINUITY. ONE INTERESTING FEATURE ON THE 00Z GFS IS A LOW THAT DROPS OUT OF EASTERN CANADA AND MOVES WESTWARD TOWARDS THE UPPER GREAT LAKES FRIDAY INTO SATURDAY. WHILE THE LATEST ECMWF DOES NOT SHOW THIS AS STRONGLY...PREVIOUS RUNS HAVE DEPICTED SUCH A FEATURE. ONE CONSISTENT FEATURE IS A 850MB HIGH OVER FAR NORTHWEST ONTARIO WHICH COULD BRING AS COLD AS 0C AIR OVER THE UPPER GREAT LAKES THIS WEEKEND. EASTERLY FLOW THIS COLD OVER A RELATIVELY WARM LAKE COULD PRODUCE SOME LAKE EFFECT /RAIN/ SHOWERS...BUT WITH QUESTIONS ABOUT THE UPPER PATTERN THROUGH THIS PERIOD CONFIDENCE REMAINS LOW. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 1233 AM CDT MON SEP 28 2015 VFR TO MVFR CONDITIONS EXPECTED THROUGH THE TAF PERIOD...WITH AS LOW AS IFR CONDITIONS AT INL AND HIB EARLY THIS MORNING. A WEAK COLD FRONT WILL CONTINUE TO MOVE ACROSS THE NORTHLAND THIS MORNING...SLOWING AS IT MOVES ACROSS NORTHWEST WISCONSIN. A FEW SHOWERS ARE POSSIBLE ALONG AND AHEAD OF THE FRONT TONIGHT INTO EARLY TOMORROW...BUT CONDITIONS SHOULD GENERALLY REMAIN VFR. BEHIND THE FRONT FOG HAS DEVELOPED IN NORTHEAST MINNESOTA INCLUDING AT HIB AND INL...AND ADDITIONAL DEVELOPMENT IS POSSIBLE AT DLH AND BRD TOWARDS MORNING. ANOTHER NIGHT OF LOW LEVEL WIND SHEAR FOR MOST TAF SITES AS WELL. BY MONDAY MORNING FOG/STRATUS SHOULD DISSIPATE WITH VFR CONDITIONS PREVAILING THROUGH THE DAY AND INTO THE EVENING WITH A LIGHT WEST WIND. && .PRELIMINARY POINT TEMPS/POPS... DLH 65 40 55 37 / 10 0 0 0 INL 61 30 55 33 / 0 0 0 0 BRD 67 39 59 38 / 20 0 0 0 HYR 67 37 58 29 / 60 0 0 0 ASX 68 40 57 34 / 30 0 0 0 && .DLH WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. LS...NONE. && $$ SHORT TERM...LE LONG TERM...JJM AVIATION...JJM
AREA FORECAST DISCUSSION
NWS JACKSON MS
454 AM CDT MON SEP 28 2015 .DISCUSSION... TODAY THROUGH TUESDAY NIGHT... MODEL CONSENSUS IS THAT THE MID/UPPER LEVEL LOW WILL MEANDER NORTHEASTWARD FROM SOUTHEAST TEXAS INTO LOUISIANA BEFORE OPENING UP AND SHEARING OUT AS IT EVENTUALLY GETS ABSORBED BY A FRONTAL BOUNDARY IN THE WESTERLIES. FOR NOW HOWEVER...DEEP CYCLONIC FLOW CONTINUES TO FUNNEL IN AN IMPRESSIVE PLUME OF TROPICAL MOISTURE FROM THE WESTERN CARIBBEAN REGION NORTHWARD TOWARD THE CENTRAL GULF COAST REGION (PRECIPITABLE WATER APPROACHING 2.5 INCHES). PER NHC GUIDANCE...IT APPEARS ANY HYBRID TROPICAL SYSTEM DEVELOPMENT ASSOCIATED WITH THE MOISTURE CHANNEL WILL BE FAR ENOUGH EAST TO NOT POSE CONCERNS FOR THE ARKLAMISS. THE HRRR DID A GOOD JOB YESTERDAY MORNING IN SIGNALING OR THE INLAND DEVELOPMENT OF HEAVIER CONVECTION ALONG THE I-59 CORRIDOR (KMEI OBSERVED > 2.5 INCHES OF RAINFALL) AND HAVE FOLLOWED IT AGAIN FOR TODAY. RECENT RUNS SUGGEST THAT THE CURRENT MESOSCALE VORTEX OVER WESTERN AL WILL CONTINUE TO SUPPORT WIDESPREAD RAINFALL THAT COULD IMPACT EASTERN MS OVER THE NEXT FEW HOURS...BUT ADDITIONAL RAINFALL AND SHOWER/TSTM DEVELOPMENT IS EXPECTED TO BE SCATTERED AND HAVE CUT BACK ON GUIDANCE POPS JUST A BIT. WEAK MID LAPSE RATES AND LIMITED DAYTIME HEATING DUE TO EXTENSIVE CLOUD COVER WILL LIMIT OVERALL TSTM POTENTIAL. AS THE SYSTEM BEGINS TO SHEAR OUT TUESDAY...RAIN CHANCES SHOULD DROP OFF SIGNIFICANTLY WITH DRIER AIR MOVING INTO THE REGION. OTHERWISE...EXPECT DAYTIME TEMPERATURES WILL CONTINUE TO BE ON THE MILD SIDE IN THIS WETTER/CLOUDIER REGIME. /EC/ WEDNESDAY THROUGH NEXT SUNDAY... THERE IS SOME UNCERTAINTY WITH REGARD TO THE SPECIFICS OF HYBRID GULF LOW DEVELOPMENT IN THE GULF OF MEXICO (OR VICINITY) IN THE COMING SEVERAL DAYS. HOWEVER...MODEL CONSENSUS IS QUITE GOOD THAT DEVELOPMENT EITHER IN THE EASTERN GULF OF MEXICO OR JUST OFF THE SOUTHEAST COAST WILL STRENGTHEN A BUILDING UPPER TROUGH DEEP DOWN INTO THE EASTERN CONUS THURSDAY AND FRIDAY. SUCH A PATTERN SHOULD HELP DRIVE A COLD FRONT THROUGH THE REGION WEDNESDAY AND PUSH ALL BUT MINUSCULE PRECIP CHANCES EAST OF OUR REGION BY THURSDAY. DESPITE THE LACK OF A TRULY CHILLY AIR MASS UP NORTH TO LATCH ONTO...THE PATTERN DEFINITELY HAS A COOL LOOK AND SHOULD BRING MOST OF THE REGION BELOW NORMAL READINGS FOR AT LEAST A FEW DAYS IN THE LONG TERM PERIOD. ONE CONCERN WHICH WILL BARE WATCHING IN THE COMING DAYS IS THE POTENTIAL FOR AN ENHANCED FIRE WEATHER RISK THURSDAY AND FRIDAY OWING TO INCREASED WINDS...RATHER LOW AFTERNOON HUMIDITY...AND THE CONTINUED DRY STRETCH OF WEATHER IN MANY LOCATIONS. OF COURSE...IF WE ARE FORTUNATE...THERE WILL BE WIDESPREAD SIGNIFICANT RAINS AROUND THE AREA OVER NEXT FEW DAYS TO ALLEVIATE MUCH OF THIS CONCERN FOR THURSDAY AND FRIDAY. DUE TO THIS FACET OF UNCERTAINTY THE HWO WILL BE LEFT CLEAR IN THIS REGARD FOR THE TIME BEING. BY NEXT WEEKEND THE NORTH AMERICAN CIRCULATION PATTERN SEEMS TO HOLD MORE THAN AN AVERAGE AMOUNT OF CHAOS THAT REMAINS TO BE WORKED OUT WITH SUFFICIENT CONFIDENCE BY NWP MODELS. REGARDLESS...POTENTIAL OF A WARMING TREND AND SLOWLY INCREASING RAIN CHANCES IS STILL DECENT OVER THIS STRETCH. /BB/ && .AVIATION...OVERALL...FLYING CONDITIONS WILL BE RATHER POOR AS WIDESPREAD MVFR/IFR CATEGORY STRATUS WILL PREVAIL FOR MUCH OF THE FORECAST PERIOD. A VERY MOIST AIRMASS ASSOCIATED WITH A LARGE AREA OF LOW PRESSURE WILL PRODUCE SCATTERED SHRA WHICH COULD IMPACT ALL TAF SITES AT SOME POINT...BUT CONFIDENCE ON EXACT TIMING IS UNUSUALLY LOW. /EC/ && .PRELIMINARY POINT TEMPS/POPS... JACKSON 77 69 83 69 / 49 41 51 29 MERIDIAN 76 68 83 67 / 68 66 51 37 VICKSBURG 82 67 84 67 / 47 40 49 27 HATTIESBURG 80 70 85 69 / 66 43 40 21 NATCHEZ 81 69 83 67 / 48 40 44 23 GREENVILLE 81 68 82 68 / 42 42 44 28 GREENWOOD 80 68 81 67 / 46 59 53 33 && .JAN WATCHES/WARNINGS/ADVISORIES... MS...NONE. LA...NONE. AR...NONE. && $$ /EC/BB/
AREA FORECAST DISCUSSION...UPDATED
NWS BILLINGS MT
1038 PM MDT SUN SEP 27 2015 .UPDATE... UPDATED FORECAST LATE THIS EVENING TO SPREAD POPS TO COVER ENTIRE FORECAST AREA THROUGH MIDNIGHT AND TO EXPAND AND ENHANCE POPS FOR THE OVERNIGHT PERIOD. RADAR SHOWING ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS ACROSS THE REGION THIS EVENING. COVERAGE IS MORE WIDESPREAD THAN MODEL FORCING WOULD SUGGEST THUS THE UPDATE. BEST CHANCES FOR PRECIPITATION OVERNIGHT WILL BE SOUTH OF A MILES CITY TO BILLINGS LINE AS ISENTROPIC LIFT AND RIGHT REAR QUAD JET ENERGY COMBINE TO ENHANCE LIFT. PRECIPITATION STILL LOOKS LIGHT AT LESS THAN A TENTH OF AN INCH IN GENERAL. CHAMBERS && .SHORT TERM...VALID FOR MON AND TUE... HEIGHTS STILL FALLING ACROSS THE AREA AS AN UPPER LEVEL TROUGH MOVES FROM ALBERTA INTO SASKATCHEWAN. HIGH PRESSURE BUILDING INTO NORTHERN MONTANA WITH THIS TROUGH MOVEMENT IS BRINGING EASTERLY LOW LEVEL FLOW AND MUCH COOLER TEMPERATURES. WATER VAPOR SHOWS MOISTURE MOVING OVER THE AREA BUT DEEPER TAP IS OVER WYOMING AND CURRENT RADAR DOES SO ANY PRECIPITATION IS LIMITED TO THE HIGHER TERRAIN OVER THE PARK AND THE BIG HORNS. WITH DEWPOINTS ON THE RISE HRRR CONTINUES TO INDICATE CLOUD COVER WILL INCREASE OVER SOUTHERN MONTANA AND LIGHT SHOWERS DEVELOPING AFTER 9 PM. UNFORTUNATELY THIS TIMING MAY IMPACT LUNAR ECLIPSE VIEWING FOR PEOPLE. MONDAY IS MOSTLY DRY WITH A CONTINUED COOLING TREND WITH HEIGHTS BUILDING WEAKLY OVER THE AREA. MONDAY NIGHT ANOTHER ROUND OF SHOWERS BECOMES POSSIBLE FOR SOUTHERN PORTIONS OF SOUTHEAST MONTANA AS A WEAK SHORTWAVE MOVES THROUGH THE AREA AND MOISTURE IS PULLED INTO THAT AREA AROUND SURFACE HIGH PRESSURE OVER THE EASTERN DAKOTAS. STILL NOT A BUNCH OF MOISTURE EXPECTED. TUESDAY HEIGHTS BUILD UPSTREAM WITH DOWNSLOPE SURFACE FLOW DEVELOPING. THIS WILL BRING A REBOUND IN TEMPERATURES AND DRYING BUT NO WHERE NEAR THE SUMMERTIME CONDITIONS SEEN EARLIER THIS WEEKEND. BORSUM .LONG TERM...VALID FOR WED...THU...FRI...SAT...SUN... EXTENDED DETERMINISTIC MODELS WERE SHOWING AGREEMENT EARLY...WHILE THE EURO ENSEMBLES CONTINUED TO SHOW UNCERTAINTY WITH THE PATTERN THROUGH THE PERIOD...AND THE GEFS SHOWED GOOD AGREEMENT UNTIL 00Z FRI. NOTED THAT DETERMINISTIC MODELS START FALLING OUT OF AGREEMENT ON FRI WITH POTENTIALLY POTENT APPROACHING WEST-COAST SYSTEM. UPPER RIDGING SHOULD DOMINATE THROUGH THURSDAY AFTERNOON... TO THEN BE REPLACED BY PACIFIC TROUGH WHEN MODEL QPF BEGINS TO INCREASE WITH ASSOCIATED FORCING IN WESTERN ZONES. THE TROUGH WILL FORM AN UPPER LOW THAT SHIFTS SE DURING FRI... WITH TRENDING RAINFALL ACCUMULATIONS IN THE SAME DIRECTION. ISOLATED TO SCATTERED POPS ARE PRESENT IN THE GRIDS TO COVER THIS CHANCE OF SHOWERS AND THUNDERSTORMS OVER MOST THE AREA ON THURSDAY THROUGH FRIDAY AFTERNOON. CURRENT SOUTHERN EXTENT OF TRACK SHOULD BRING COOLER WEATHER INTO THE AREA GRADUALLY... AS THE FRONTAL COMPLEX AND SFC LOW ALSO REMAINS FURTHER SOUTH. GFS SOLUTION HAS MID-LEVEL TEMPS AND QPF IN FAVOR OF AT LEAST SOME MOUNTAIN SNOWFALL THROUGH SUNDAY AFTERNOON BUT EURO IS SIGNIFICANTLY WARMER AND DRIER IN THE SAME PERIOD. THIS SOLUTION BRINGS AN UPPER LOW ONTO THE CENTRAL CA COST...WHILE THE GFS HAD THE LOW NEARBY BUT MUCH WEAKER..WITH DOWNSTREAM RIDGING IN THE EURO LIKELY THE SOURCE OF WARMER TEMPS. BOTH MODELS THUS HAD VERY DIFFERENT VERSIONS OF FLOW OVER THE REGION BY THE END OF THE PERIOD...WITH SW IN THE EURO AND SOME WEAK CYCLONIC CURVATURE IN THE NW FLOW FROM THE GFS... BUT THE REST OF THE PERIOD WAS DRY IN BOTH MODELS. MROWELL && .AVIATION... ISOLATED TO SCATTERED SHOWERS WILL IMPACT AREAS ALONG AND SOUTH/ EAST OF A KLVM-KBIL-KMLS LINE TONIGHT. VFR SHOULD PREVAIL AT LOWER ELEVATIONS BUT THE BEARTOOTH/ABSAROKA AND BIGHORN MOUNTAINS WILL BE OCCASIONALLY OBSCURED. SHOWERS WILL TAPER OFF FROM WEST TO EAST LATE TONIGHT. IT WILL BE DRY WITH VFR CONDITIONS ACROSS THE AREA ON MONDAY. JKL && .PRELIMINARY POINT TEMP/POPS... MON TUE WED THU FRI SAT SUN ----------------------------------------------------------- BIL 049/068 046/078 051/081 053/072 051/065 047/059 041/063 20/B 00/U 01/U 35/W 53/W 22/W 11/B LVM 041/069 042/078 046/081 048/068 046/064 044/058 039/062 20/U 00/U 01/B 34/W 32/W 22/W 22/W HDN 047/070 044/079 048/084 050/076 048/067 045/062 041/068 30/B 01/B 11/U 35/W 52/W 22/W 11/B MLS 049/068 044/077 048/081 052/077 050/066 046/063 042/066 21/B 01/B 11/U 25/W 43/W 22/W 11/B 4BQ 050/066 046/077 049/082 051/076 049/067 046/064 043/068 41/E 01/B 21/U 13/W 54/W 22/W 21/B BHK 047/064 043/072 047/078 049/073 048/064 044/062 041/064 32/W 01/B 21/U 23/W 44/W 21/B 11/B SHR 046/069 043/079 047/082 048/075 048/067 042/063 039/068 31/B 11/B 11/B 24/W 33/W 22/W 11/B && .BYZ WATCHES/WARNINGS/ADVISORIES... MT...NONE. WY...NONE. && $$ WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS BUFFALO NY
445 AM EDT MON SEP 28 2015 .SYNOPSIS... A SOUTHERLY FLOW OF MOIST AIR WILL BRING SCATTERED SHOWERS TO THE ENTIRE REGION TODAY. MORE WIDESPREAD SHOWERS WILL MOVE INTO THE AREA TUESDAY WITH THE APPROACH OF A COLD FRONT. MUCH COOLER AND DRIER AIR WILL ARRIVE WEDNESDAY BEHIND THE FRONT AND LAST THROUGH THE END OF THE WEEK. && .NEAR TERM /THROUGH TONIGHT/... AN INCREASINGLY MOIST AIR MASS WILL FED INTO OUR REGION FROM THE OHIO VALLEY AND MID ATLANTIC STATES TODAY. AN AREA OF SCATTERED SHOWERS WILL PUSH ACROSS THE AREA TODAY AS A SUBTLE MID LEVEL VORTICITY MAXIMA MOVES NORTHWARD AND INCREASES LARGE SCALE ASCENT. LATEST HRRR QPF FIELDS SUGGESTING THAT THE BULK OF THE SHOWER ACTIVITY WILL OCCUR DURING THE FIRST HALF OF THE DAY AS THE UPPER SUPPORT CROSSES THE REGION FOLLOWED BY A DIMINISHING TREND THIS AFTERNOON AND TONIGHT. THE INCOMING WARMER AIRMASS WILL ALLOW HIGHS TO REACH THE LOWER TO MID 70S ON THE LAKE PLAINS TODAY WITH AN ADDED BOOST FROM A FAVORABLE DOWNSLOPE FLOW. THE HIGHER TERRAIN OF THE SOUTHERN TIER WILL STAY IN THE MID TO UPPER 60S WITH THICKER...LOWER CLOUD COVER. && .SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... A PLUME OF DEEP ATLANTIC MOISTURE CHARACTERIZED BY PRECIPITABLE WATER VALUES NEAR 1.5IN /MORE THAN 2SD ABOVE NORMAL/ WILL LIE ACROSS NEW YORK STATE INTO TUESDAY. THIS MOISTURE WILL BE CIRCULATING AROUND A HIGH PRESSURE CENTER OFF THE NEW ENGLAND COAST WHILE A BROAD 500MB TROUGH AND SURFACE COLD FRONT APPROACH FROM THE WESTERN GREAT LAKES. A COMBINATION OF SURFACE MOISTURE CONVERGENCE AND SERIES OF UPPER LEVEL VORTICITY MAXIMA EXITING THE BASE OF THE 500MB TROUGH WILL LIKELY CONTRIBUTE TO SEVERAL ROUNDS OF HIT AND MISS SHOWERS AND EXTENSIVE CLOUD COVER INTO TUESDAY AHEAD OF THE APPROACHING COLD FRONT. INSTABILITY AND SHEAR ARE FORECAST TO INCREASE TUESDAY AFTERNOON WITH CAPE VALUES RISING OVER 1000 J/KG AND BULK SHEAR OF 30-35 KTS. THIS SHOULD PROMOTE SOME THUNDERSTORM ACTIVITY AHEAD OF AND ALONG THE COLD FRONT AS IT IS FORECAST TO CROSS WESTERN AND CENTRAL NEW YORK TUESDAY AFTERNOON AND EVENING. THE HIGH MOISTURE AIRMASS WILL KEEP MILD TEMPERATURES IN PLACE WITH HIGHS ON TUESDAY INTO THE 70S WITH A BREEZY SOUTHERLY FLOW AHEAD OF THE COLD FRONT. DOWNSLOPING ACROSS THE ONTARIO LAKE PLAINS AND GENESEE RIVER VALLEY SHOULD SUPPORT MID 70S IN THESE WARMER LOCATIONS. A BROAD CANADIAN SURFACE HIGH WILL BUILD IN BEHIND THE COLD FRONT TUESDAY NIGHT THROUGH THE END OF THE WEEK. THIS WILL BRING A PUNCH OF DRY CONTINENTAL POLAR AIR SOUTH ACROSS THE GREAT LAKES CLEARING SKIES AND KNOCKING BACK TEMPERATURES TO MORE SEASONABLE LEVELS. THE INITIAL SURGE OF COLD ADVECTION RIGHT BEHIND THE FRONT WILL MIX GUSTY WINDS OF 20-30 MPH TO THE SURFACE OVERNIGHT TUESDAY INTO WEDNESDAY AND THE NORTHERLY FLOW ACROSS LAKE ONTARIO MAY LINGER LOW CLOUDS ACROSS WESTERN NEW YORK WITH CLEARING FIRST EAST OF LAKE ONTARIO. TEMPERATURES WILL FEEL MORE FALL-LIKE WEDNESDAY WITH HIGHS ONLY RISING INTO THE UPPER 50S TO LOWER 60S WITH DEWPOINTS SLIPPING BACK TO AROUND 40. LOWS WEDNESDAY NIGHT WILL SLIP TO THE MID TO UPPER 40S FOR LOWER ELEVATIONS AND URBAN AREAS...WITH LOW 40S TO UPPER 30S ACROSS HIGHER TERRAIN OF THE SOUTHERN TIER AND ACROSS THE EASTERN LAKE ONTARIO REGION. && .LONG TERM /THURSDAY THROUGH SUNDAY/... BROAD SURFACE HIGH PRESSURE WILL BE FOUND ACROSS THE GREAT LAKES AND EASTERN CANADA THROUGH THE END OF THE WEEK WHILE SPLIT SUBTROPICAL AND POLAR JETS DIG STACKED TROUGHS ACROSS EASTERN NORTH AMERICA. THIS PATTERN WILL KEEP SEASONABLY COOL AND DRY WEATHER IN PLACE ACROSS WESTERN AND NORTH CENTRAL NEW YORK THURSDAY AND FRIDAY. 12Z ECMWF AND GFS MODELS SHOW VASTLY DIFFERENT SOLUTIONS FOR THE WEATHER NEXT WEEKEND WITH BOTH MODELS SHOWING CUT OFF LOWS DEVELOPING. THE EC LOW JUST NORTH OF THE EASTERN GREAT LAKES KEEPS ATLANTIC MOISTURE EAST AND NORTH OF THE FORECAST AREA LEAVING WESTERN AND CENTRAL NEW YORK COOL BUT MAINLY DRY WHILE THE GFS LOW OVER THE SOUTHEAST STATES WOULD ADVECT DEEP ATLANTIC MOISTURE NORTH ACROSS OUR REGION WHICH WOULD YIELD WETTER AND WARMER WEATHER. THERE IS A LOT OF ROOM AND TIME FOR MODELS TO BECOME BETTER ALIGNED FOR NEXT WEEKEND SO JUST INCLUDED A SLIGHT CHANCE OF SHOWERS FOR NOW. HIGH TEMPERATURES THROUGH THE LONG TERM PERIOD LOOK TO ONLY TOP OUT AROUND 60 WITH COOL OVERNIGHT LOWS DIPPING INTO THE 40S. && .AVIATION /09Z MONDAY THROUGH FRIDAY/... EARLY THIS MORNING...INCREASING MOISTURE WILL BE ADVECTED INTO OUR REGION FROM THE OHIO VALLEY AND MID ATLANTIC STATES. THIS WILL RESULT IN INCREASING/THICKENING CLOUDS FROM SOUTHWEST TO NORTHEAST...WITH SCATTERED SHOWERS ACROSS FAR WESTERN NEW YORK WITH THE ARRIVAL OF DEEPER MOISTURE AND A WEAK MID LEVEL SHORTWAVE. LATER TODAY...SKIES WILL REMAIN MOSTLY CLOUDY...WHILE THE SCATTERED SHOWERS OVERSPREAD THE REMAINDER OF THE REGION. IN TERMS OF CIGS...ACROSS THE LOWER ELEVATIONS THESE WILL DEVELOP AND LOWER THROUGH THE VFR RANGE THIS MORNING...THOUGH WILL LIKELY NOT DROP BELOW THAT DUE TO THE PREVAILING SOUTHERLY DOWNSLOPE FLOW AT THE LOWER LEVELS. ACROSS THE HIGHER TERRAIN...INCREASING LOW LEVEL MOISTURE SHOULD LEAD TO THE DEVELOPMENT OF MVFR CIGS WHICH SHOULD PERSIST THROUGH A GOOD CHUNK OF TODAY...WITH SOME IFR CIGS NOT OUT OF THE QUESTION THIS MORNING. AS FOR VSBYS...WITH THE SHOWER ACTIVITY EXPECTED TO REMAIN ON THE LIGHT AND SCATTERED SIDE...EXPECT THESE TO LARGELY REMAIN VFR THROUGH THE PERIOD. OUTLOOK... TUESDAY...VFR/MVFR WITH SHOWERS LIKELY AND POSSIBLY A THUNDERSTORM. WEDNESDAY THROUGH FRIDAY...VFR. && .MARINE... SOUTHERLY WINDS MOSTLY IN THE 10 TO 15 KNOT RANGE WILL CONTINUE TODAY...THROUGH AT LEAST THE FIRST PART OF TUESDAY AS HIGH PRESSURE WILL BE LARGELY ANCHORED OFF THE NEW ENGLAND COAST. WHILE SOME AREAS OVER THE OPEN WATERS OF BOTH LAKES WILL SEE WINDS INCREASING TO THE 15-20 KNOT RANGE FOR A PERIOD TODAY...THE RESULTANT HIGHER WAVES WILL PREDOMINANTLY REMAIN OVER CANADIAN WATERS. AFTER THAT...A COLD FRONT WILL THEN CROSS THE LOWER LAKES TUESDAY AFTERNOON AND EVENING. INCREASING NORTHERLIES BEHIND THIS FRONT WILL LIKELY BRING A ROUND OF ADVISORY CONDITIONS TO BOTH LAKES FOR THE MIDDLE OF THE WEEK. && .BUF WATCHES/WARNINGS/ADVISORIES... NY...NONE. MARINE...NONE. && $$ SYNOPSIS...TMA NEAR TERM...TMA SHORT TERM...WCH LONG TERM...SMITH AVIATION...HITCHCOCK/JJR/TMA MARINE...TMA
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
419 AM EDT MON SEP 28 2015 .SYNOPSIS... SHOWERS WILL BE POSSIBLE TODAY, MAINLY OVER THE FINGER LAKES AND CENTRAL NEW YORK. SHOWERS WILL BECOME MORE LIKELY ON TUESDAY INTO WEDNESDAY, AS A COLD FRONT PUSHES INTO THE REGION. && .NEAR TERM /THROUGH TONIGHT/... 400 AM UPDATE... AFTER GETTING LUCKY FOR MOST OF THE AREA LAST NIGHT BEING CLEAR ENOUGH TO VIEW THE ECLIPSE, REALITY IS SETTING IN WITH THICK CLOUDS ON OUR DOORSTEPS WITH SOME SHOWERS NOT FAR BEHIND. FOLLOWED LATEST HRRR QPF FIELDS AND INCREASED TO LIKELY POPS THROUGH MID MORNING FROM THE WESTERN SOUTHERN TIER UP THROUGH FINGER LAKES. PRECIP SHOULD MAKE IT TO CNY BUT MAY BREAK UP A BIT BY THE TIME THAT HAPPENS. LATER TODAY AND THROUGH TONIGHT RAIN CHANCES DON`T LOOK ALL THAT GREAT BUT WE CAN`T RULE ANYTHING OUT, ESPECIALLY IN PRETTY MUCH THE SAME AREAS JUST MENTIONED ABOVE. FARTHER SOUTH ESPECIALLY INTO PA, MAINLY DRY WEATHER IS EXPECTED. && .SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... 4 AM UPDATE... ALTHOUGH MY GARDEN IS WINDING DOWN DUE TO THE LOSS OF DAYLIGHT/LOW SUN ANGLE, I AM GETTING EXCITED ABOUT THE POSSIBILITY OF SOME RAIN AROUND HERE! RAIN CHANCES GO UP FOR OUR AREA BY TUESDAY AFTERNOON AS A COLD FRONT APPROACHES. CONTINUE TO MENTION SOME ISOLATED THUNDER THROUGH EARLY TUESDAY NIGHT TO MATCH WELL WITH OTHER OFFICES ALONG WITH THE FACT LI`S ARE NEAR OR BELOW ZERO. UNLIKE PAST RAIN EVENTS WITH EACH MODEL RUN WE ARE LOOKING AT INCREASING CHANCES FOR HIGHER RAINFALL AMOUNTS INSTEAD OF LOWER ONES. IN FACT THE MAIN TREND OF THE 0Z RUNS OF BOTH THE EURO AND GFS NOT ONLY RAISE RAINFALL AMOUNTS, THE PROGRESSION OF THE COLD FRONT THROUGH OUR AREA IS MUCH SLOWER. ACCORDINGLY I RAISED POPS ABOVE 70% FOR THE ENTIRE AREA TUESDAY NIGHT. IN FACT THROUGH MUCH OF WEDNESDAY NOW, WE HAVE POPS ABOVE 60% FROM NEAR BINGHAMTON SOUTH AND EAST. DRIER WEATHER NOW HOLDS OFF UNTIL WED NIGHT. AT EARLY LOOK AT TOTAL RAINFALL AMOUNTS WOULD BE A HALF OF AN INCH UP ACROSS THE FINGER LAKES, BUT EXCEEDING AN INCH FROM NEAR BINGHAMTON SOUTH AND EAST, WHERE PRECIP LINGERS THE LONGEST. && .LONG TERM /THURSDAY THROUGH SUNDAY/... 200 PM SUNDAY UPDATE... THOUGH DIFFERING ON DETAILS...MODELS ARE STARTING TO GET INTO BETTER LARGE SCALE AGREEMENT...ON THE IDEA OF AN UNSETTLED TROUGHY PATTERN TAKING SHAPE BY NEXT WEEKEND. ONSHORE FLOW...CUTOFF LOW EVOLUTION...AS WELL AS POTENTIAL COASTAL SURFACE LOW...MAY ALLOW MOISTURE TO START CREEPING IN AS EARLY AS FRIDAY AFTERNOON- NIGHT...BUT THE END RESULT DOES APPEAR TO BE COOL AND WET PERIODS INTO NEXT WEEKEND. BEFORE THEN...MAINLY DRY WITH TEMPERATURES SLIGHTLY BELOW CLIMATOLOGY THANKS TO FEED OF AIR FROM SURFACE HIGH PRESSURE IN QUEBEC. A FRONTAL ZONE WILL BE STALLED OUT NOT TOO FAR SOUTHEAST OF US...SO THAT WILL NEED TO BE MONITORED...BUT KEEPING FORECAST GENERALLY DRY FOR NOW WEDNESDAY NIGHT THROUGH THURSDAY NIGHT. && .AVIATION /08Z MONDAY THROUGH FRIDAY/... HIPRES OVER NEW ENG WILL ALLOW AN ELY FLOW OF MOISTURE INTO THE AREA. THIS WILL RESULT IN SOME MVFR CLD CIGS THIS MRNG...SLOWLY RETURNING TO VFR IN THE LATE MRNG AS HTG ERODES THE CLDS. OTRW...LTL IN THE WAY OF WX FOR THE NEST 24 HRS. .OUTLOOK... MONDAY NIGHT-TUESDAY NIGHT...CHC -SHRA AND ASSOCIATED RESTRICTIONS. BEST CHANCE WITH FRONTAL PASSAGE TUE-TUE NGT. WEDNESDAY-FRIDAY...MAINLY VFR EXCEPT FOR LOCAL RESTRICTIONS DUE TO VALLEY FOG /MAINLY KELM/. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...NONE. NY...NONE. && $$ SYNOPSIS...HEDEN NEAR TERM...HEDEN SHORT TERM...HEDEN LONG TERM...MDP AVIATION...DGM/DJP
AREA FORECAST DISCUSSION
NWS RALEIGH NC
340 AM EDT MON SEP 28 2015 .SYNOPSIS...DEEP ATLANTIC MOISTURE WILL CONTINUE TO PUMP INTO THE REGION TODAY... BETWEEN CANADIAN HIGH PRESSURE TO OUR NORTHEAST AND LOW PRESSURE JUST OFF THE SOUTHEAST COAST. THESE FEATURES WILL WEAKEN TONIGHT INTO TUESDAY... RESULTING IN A BRIEF IMPROVEMENT IN WEATHER CONDITIONS... HOWEVER A SURGE OF GULF MOISTURE AHEAD OF AN APPROACHING COLD FRONT WILL BRING A RETURN TO WET AND UNSETTLED WEATHER LATE TUESDAY THROUGH THURSDAY. && .NEAR TERM /TODAY THROUGH TONIGHT/... AS OF 320 AM MONDAY... COLUMN REMAINS VERY MOIST THIS MORNING... ALTHOUGH THE EXTENT OF MOISTURE THROUGH THE COLUMN IS NOT QUITE WHAT IT`S BEEN THE LAST COUPLE OF DAYS. WE`RE IN GRADUAL TRANSITION AWAY FROM THE DYING WEDGE REGIME TO AN ATYPICALLY HUMID (ESP FOR LATE SEPTEMBER) AIR MASS. THE PARENT HIGH WHICH BROUGHT THE DAMMING OVER THE WEEKEND IS NOW CENTERED WELL OUT OVER THE NW ATLANTIC YET STILL NOSING WEST AND SW INTO THE WRN CAROLINAS. THE STABLE POOL OVER THE WRN PIEDMONT HAS WEAKENED... AND THE AIR MASS HAS BECOME MORE HOMOGENEOUS ACROSS THE CWA... DEMONSTRATED BY TEMP/DEWPOINT RANGES OF JUST AROUND 4 DEGREES ACROSS CENTRAL NC... AND UNIFORM OBSERVED LIFTED INDICES AND CINH. MUCH OF THIS PAST EVENING`S LIGHT PRECIP DRIVEN BY ISENTROPIC UPGLIDE HAS SHIFTED WELL NW OUT OF THE AREA... LEAVING JUST WIDESPREAD STRATUS AND PERHAPS A FEW ISOLATED DRIZZLE PATCHES. THIS RELATIVE LULL IN PRECIP WILL CONTINUE THROUGH THE MID MORNING HOURS... HOWEVER AREAS OF SHOWERS NOW JUST OFF THE NC COAST ARE ON TRACK TO TRANSLATE WEST OR WNW INTO THE COASTAL PLAIN AND THEN INTO THE PIEDMONT FROM MID/LATE MORNING THROUGH THE AFTERNOON... WITH COVERAGE FILLING IN AS HEATING ALLOWS FOR A FEW HOLES IN THE CLOUDS AND SUBSEQUENT (WEAK) DESTABILIZATION... WITH LIFT POTENTIALLY AUGMENTED BY A WEAK WAVE TRACKING NE OVER ERN NC THIS AFTERNOON. EXPECT LOW POPS THIS MORNING... TRENDING UP TO LIKELY EAST AND CHANCE WEST... WITH HIGHER POPS THEN PUSHING WNW INTO THE WRN PIEDMONT AS WE GET INTO THE EVENING HOURS... A PATTERN SUGGESTED BY RECENT RUNS OF BOTH LARGE SCALE AND CONVECTION ALLOWING MODELS INCLUDING THE SREF/GFS/3 KM NAMRR AND THE LATEST HRRR RUNS. FORECAST SOUNDINGS SHOW A DEEP WARM LAYER THIS AFTERNOON WITH AN LCL-TO- FREEZING-LEVEL DEPTH OVER 4 KM... ALONG WITH PW VALUES OF 2.0-2.3 INCHES... SO ANY SHOWERS FORMING TODAY WILL BE CAPABLE OF DROPPING BRIEF HEAVY RAIN. FORECAST MUCAPE FOR TODAY IS UNIMPRESSIVE (UNDER 1000 J/KG... MOST OF WHICH IS BELOW THE -10C LEVEL) WITH GENERALLY SUB-20-KT DEEP LAYER BULK SHEAR... SO WILL NOT MENTION THUNDER AT THIS TIME... ALTHOUGH A STRIKE OR TWO IS CERTAINLY POSSIBLE IN THE COASTAL PLAIN. EXPECT THE AREA OF BETTER SHOWER COVERAGE TO CONTINUE SHIFTING WNW TOWARD THE FOOTHILLS DURING THE EVENING... SO WILL TREND POPS DOWN FROM EAST TO WEST TONIGHT... RESULTING IN 30-40% CHANCES NORTHWEST TRANSITIONING DOWN TO JUST ISOLATED SHOWERS EAST OF HIGHWAY 1 OVERNIGHT. STRATUS REDEVELOPMENT APPEARS LIKELY LATE TONIGHT GIVEN THE LOW LEVEL MOISTURE AND TRAJECTORIES ALONG WITH PERSISTENCE... ALTHOUGH A LIGHT BREEZE FROM THE NE -- AS MODELS SUGGEST -- MAY INHIBIT FOG DEVELOPMENT. WILL LEAVE IN A MENTION OF PATCHY FOG FOR NOW. EXPECT HIGHS FROM THE MID 70S NW (WHERE THE AIR IS STILL A BIT MORE STABLE AND MORE RESISTANT TO MIXING AND THUS SHOULD SEE LESS SUNSHINE) TO AROUND 80-82 EAST OF HIGHWAY 1... WITH MOSTLY CLOUDY SKIES. MILD LOWS TONIGHT OF 67-71... AROUND 10 DEG ABOVE NORMAL. -GIH && .SHORT TERM /TUESDAY THROUGH TUESDAY NIGHT/... AS OF 330 AM MONDAY... CONTINUED MOIST WITH A GOOD CHANCE OF SHOWERS... AND PERHAPS A STORM OR TWO. THE MID LEVEL TROUGH FROM THE LOWER GREAT LAKES THROUGH THE LOWER MISS VALLEY TO LA WILL CONTINUE TO TILT SLOWLY... RESULTING IN A GRADUAL INCREASE IN MID LEVEL VORTICITY MOVING FROM THE NW GULF INTO THE CAROLINAS ON WEAK SOUTHWESTERLY MID LEVEL FLOW. THE LOW LEVEL ATLANTIC INFLOW SHOULD BE ON THE DECREASE WITH A REDUCED FETCH... A FUNCTION OF WHAT IS NOW TD #11 AS IT PUSHES SLOWLY NW/NNW ON ITS ANTICIPATED TRACK TOWARD THE OFFSHORE WATERS OF NC. PW IS PROJECTED TO REMAIN VERY HIGH AT 2.0-2.3 INCHES... WELL ABOVE SEASONAL NORMALS... AND MODELS SHOW SLIGHTLY BETTER POTENTIAL FOR INSTABILITY TUE AFTERNOON WITHIN PERSISTENT HIGH THETA-E ADVECTION IN THE LOW LEVELS. DESPITE THE WEAK WIND FIELD AND MARGINAL DPVA... WE SHOULD SEE DECENT UPPER DIVERGENCE OVER THE AREA IN THE LEFT EXIT REGION OF THE BROAD JET FROM THE GULF INTO THE TN VALLEY. WILL TREND POPS UP TO LIKELY OVER MUCH OF THE CWA BY AFTERNOON... WANING GRADUALLY IN THE EVENING/NIGHTTIME BUT STAYING AT 30-50%... WITH BETTER SHOWER CHANCES SHIFTING WNW INTO THE NW PIEDMONT AND FOOTHILLS WITH TIME. SLIGHTLY BETTER CAPE AND SHEAR ARE EXPECTED... STILL MARGINAL THOUGH... SO HAVE INCLUDED JUST A MENTION OF ISOLATED THUNDER IN THE AFTERNOON. HIGHS 75-83 AND LOWS 66-71... BOTH ABOVE NORMAL... WITH MOSTLY CLOUDY SKIES HOLDING FIRM. -GIH && .LONG TERM /WEDNESDAY THROUGH SUNDAY/... AS OF 327 AM MONDAY... UNCERTAINTY IN THE FORECAST IS ABOUT AS HIGH AS CAN BE ADVERTISED FROM MID WEEK INTO THE WEEKEND. THE OPERATIONAL MODELS CONTINUE TO SHOW PLENTY OF SPREAD AND EVEN THE ENSEMBLE MEANS ARE CONFLICTING ON THE PLACEMENT OF THE IMPORTANT WEATHER PRODUCING SYSTEMS. THE MAIN WEATHER HAZARDS SHOULD BE LIMITED TO A LOW END HEAVY RAIN THREAT... BUT SIGNIFICANT RAINFALL MAY BE MORE OF A HELP TO CURRENT DROUGHT STATUS THAN IT WOULD BE A THREAT FOR FLOODING. THE QPF MID TO LATE WEEK IS THE MAIN QUESTION AS ABOUT 30 PERCENT OF THE MODELS INDICATE THE HEAVIEST RAIN INLAND WITH OVERRUNNING RAINS AGAIN THU NIGHT INTO SATURDAY... WHICH 70 PERCENT OF THE MODELS SUPPORT THE HEAVY SWATH OF QPF ALONG OR JUST OFF THE MID-ATLANTIC COAST. ONE THING SEEMS TO BE MORE CERTAIN SHOULD BE THE COOLER TEMPERATURES AGAIN AS ANOTHER STRONG SURFACE HIGH IS EXPECTED TO BUILD SOUTH INTO NC/SC THURSDAY INTO THE WEEKEND. THIS OCCURS AS A TROUGH ALOFT AND LINGERING LOW LEVEL BOUNDARY CONTINUE TO BE FORECAST BY MOST MODELS TO BRING A CONTINUATION OF THE UNSETTLED PATTERN THAT BEGAN LATE LAST WEEK. A RETURN TO A PROLONGED NE FLOW... CONSIDERABLE CLOUDINESS... AND POSSIBLY SIGNIFICANT RAIN IS EXPECTED THU-SAT. && .AVIATION /06Z MONDAY THROUGH FRIDAY/... AS OF 115 AM MONDAY... MOIST AND DEEP LOW LEVEL FLOW FROM THE EAST WILL CONTINUE TO BRING MOSTLY ADVERSE AVIATION CONDITIONS TODAY... ESPECIALLY AT INT/GSO... WHERE IFR/LIFR CIGS AND MVFR/IFR VSBYS ARE LIKELY TO HOLD THROUGH 13Z... ALONG WITH PATCHY DRIZZLE. FARTHER EAST AT RDU/RWI/FAY... MVFR CIGS SHOULD HOLD THROUGH 13Z... ALTHOUGH RWI MAY BREAK OUT TO VFR FOR A SHORT TIME... AND RDU COULD DROP TO IFR IN THE PREDAWN HOURS. SOON AFTER 13Z... CIGS AT ALL LOCATIONS SHOULD START TO SLOWLY LIFT TO MVFR... LASTING UNTIL AROUND 18Z OR 19Z WHEN SOME BREAKS IN THE CLOUDS ARE EXPECTED... ALTHOUGH ANY SCT/BKN CLOUDS ARE STILL LIKELY TO BE BASED AT 2500-3000 FT AGL. A TREND BACK TO MVFR TO IFR CIGS IS EXPECTED BY MID EVENING (AFTER 00Z TUE). THE LLWS THREAT OF PREVIOUS NIGHTS IS MUCH LOWER AS THE EASTERLY WINDS JUST OFF THE SURFACE (AT 1000-2000 FT AGL) HAVE WEAKENED. A FEW SHOWERS ARE POSSIBLE THIS AFTERNOON AND COULD PRODUCE A PERIOD OF SUB-VFR VSBYS. LOOKING BEYOND 06Z TUE: IFR CONDITIONS ARE EXPECTED TO RULE OVERNIGHT THROUGH DAYBREAK TUE... ALTHOUGH RWI MAY STAY MVFR FOR MUCH OF THE NIGHT WITH PATCHY FOG. INT/GSO SHOULD STAY IFR OR MVFR THROUGH TUE BUT RDU/RWI/FAY SHOULD LIFT TO MVFR THEN PERHAPS LOW-END VFR TUE AFTERNOON. IFR/LIFR CONDITIONS IN FOG ARE EXPECTED TO RETURN LATE TUE EVENING THROUGH DAYBREAK WED. VFR CONDITIONS THROUGH MIDDAY WED BUT SHOWERS AND STORMS AHEAD OF A COLD FRONT MAY BRING SUB-VFR CONDITIONS WED/WED NIGHT. THIS FRONT WILL MOVE THROUGH WED NIGHT AND STALL TO OUR SE INTO FRI... POTENTIALLY BRINGING A RETURN TO PREDOMINANTLY POOR AVIATION CONDITIONS WITHIN AREAS OF RAIN/DRIZZLE. -GIH && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...HARTFIELD NEAR TERM...HARTFIELD SHORT TERM...HARTFIELD LONG TERM...BADGETT AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1236 AM EDT MON SEP 28 2015 .SYNOPSIS... A COASTAL TROUGH WILL WEAKEN AND DISSIPATE TODAY. A FRONT WILL REACH THE AREA ON WEDNESDAY AND THEN STALL JUST OFFSHORE. DEEP MOISTURE STREAMING NORTH FROM THE GULF OF MEXICO MAY BRING A WIDESPREAD RAIN EVENT TO THE AREA LATE TUESDAY THROUGH THURSDAY. LOW PRESSURE DEVELOPING OFFSHORE MAY CREATE MORE UNSETTLED WEATHER FRIDAY AND SATURDAY. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... AS OF 1230 AM MONDAY...IMPRESSIVE CONVERGENCE BAND NEAR CAPE FEAR CONTINUES TO FEED SHOWERS WESTWARD ALONG THE BRUNSWICK COUNTY COAST TO JUST NORTH OF MYRTLE BEACH. LATEST HRRR MODEL INDICATES THIS FEATURE MAY BE WITH US FOR ANOTHER 3-5 HOURS...SO FORECAST POPS HAVE BEEN RAISED TO 60-80 PERCENT FROM SOUTHPORT THROUGH LITTLE RIVER. OTHERWISE...NO SIGNIFICANT CHANGES WERE MADE TO THE FORECAST AT THIS TIME. DISCUSSION FROM 1000 PM SUNDAY FOLLOWS... RADAR CONTINUES TO SHOW SCATTERED SHOWERS MOVING ONSHORE IN EASTERLY FLOW. TENDENCY THIS EVENING HAS BEEN FOR THEM TO WEAKEN AS THEY MOVE ON THE COAST AND COVERAGE HAS BEEN ON A SLOW DOWN TREND. HAVE TRENDED POPS BACK TOWARD CHANCE/SLIGHT CHANCE CATEGORIES FOR MUCH OF THE NIGHT WITH LOWS INVOF 70 UNDER A MAINLY CLOUDY SKY. && .SHORT TERM /6 AM THIS MORNING THROUGH TUESDAY NIGHT/... AS OF 300 PM SUNDAY...A COASTAL TROUGH WILL REMAIN IN CLOSE PROXIMITY AND MAY EVEN MOVE ONSHORE FOR A TIME ON MON BEFORE FINALLY LIFTING OUT DURING TUE. VERY HIGH PRECIPITABLE WATER VALUES...99TH PERCENTILE...REMAIN ACROSS THE AREA ON MON WITH SOME SLIGHT DRYING ON TUE AS THE PREVAILING LOW-LEVEL FLOW...WHICH HAS BEEN EASTERLY FOR DAYS...BECOMES SOUTH AND SOUTHWEST. NORMALLY...THIS WOULD SIGNAL A CHANCE TO DRY OUT AND ALLOW FOR MORE IN THE WAY OF SUNSHINE. HOWEVER...DEEP MOISTURE FROM THE GULF OF MEXICO WILL BE STREAMING NORTHWARD AS TROPICAL LOW PRESSURE MAKES A RUN FOR THE NE GULF COAST. THIS MAY NECESSITATE EVEN HIGHER POPS FOR TUE THAN ON MON AND OVER THE ENTIRE FORECAST AREA. THUS...WILL BE KEEPING POPS ELEVATED AND AS HIGH AS LIKELY AND INCLUDE A MENTION OF ISOLATED THUNDERSTORMS TUE/TUE NIGHT AS MIXED LAYER CAPE VALUES BEGIN TO INCREASE IN DEEPENING SW FLOW AND WE BEGIN TO SEE SIGNIFICANT LIFT DEVELOP THROUGH A MUCH DEEPER LAYER LATE IN PERIOD AND ON WED. CONSIDERABLE CLOUD COVER WILL CONTINUE...ALTHOUGH FORESEE MORE IN THE WAY OF BREAKS OF PARTIAL SUNSHINE DEVELOPING AS COMPARED TO THE PAST SEVERAL DAYS AS WEDGE WEAKENS AND IS DISPLACED WESTWARD. THEREFORE...TEMPS SHOULD BE CLOSER TO CLIMATOLOGY THROUGHOUT AND WILL FORECAST MORE WIDESPREAD LOWER 80S FOR HIGHS BOTH DAYS. LOWS MAINLY IN THE UPPER 60S TO AROUND 70...WHICH WILL BE SEVERAL DEGREES ABOVE NORMAL. && .LONG TERM /WEDNESDAY THROUGH MONDAY/... AS OF 300 PM SUNDAY...THE MEDIUM RANGE FORECAST LOOKS TO BE DOMINATED BY WEAK TROUGHING AT THE MID LEVELS ACROSS THE EASTERN U.S. THE GUIDANCE IS WAVERING BETWEEN CLOSED LOW PRESSURE DEVELOPING IN THE EAST OR WEAK TROUGHING. REGARDLESS AT THE SURFACE...MASSIVE HIGH PRESSURE WILL DEVELOP WELL TO THE NORTHEAST AND REMAIN ENTRENCHED ACROSS THE SOUTHEAST THROUGH SATURDAY. LINGERING LOW PRESSURE WHICH NEVER GETS SWEPT OUT INTO THE ATLANTIC RETROGRADES SLIGHTLY SATURDAY AND SUNDAY. THE HIGHEST POPS OCCUR WEDNESDAY AS A 500MB TROUGH MOVES ACROSS PICKING UP LINGERING MOISTURE AND DYNAMICS FROM THE GULF OF MEXICO. THE ATTENDANT FRONT WILL MOVE SLOWLY ACROSS SLOWLY BY LATER THURSDAY WITH SOME LINGERING DRIZZLE OR LIGHT RAIN THURSDAY INTO FRIDAY. OVERALL THE TEMPERATURE FORECAST IS CHARACTERIZED BY LIMITED DIURNAL RANGES WITH EXPECTED CLOUD COVER AND POSSIBLE SHOWERS AND DRIZZLE. && .AVIATION /06Z MONDAY THROUGH FRIDAY/... AS OF 06Z...SHOWERS ARE STILL STREAMING ONSHORE JUST NORTH OF MYRTLE BEACH AND THIS SHOULD CONTINUE THROUGH THE PRE-DAWN HOURS THIS MORNING. WHERE CIGS ARE NOT IFR...THEY SHOULD DROP TO IFR SHORTLY...REMAINING THERE THROUGH 13-15Z. COMPUTER MODELS INDICATE DRY AIR ARRIVING IN THE MID LAYERS BY DAYBREAK...SO DO NOT THINK SHOWERS WILL BE AS PREVALENT AFTER DAYBREAK. GOOD CHANCE FOR VFR IN THE AFTERNOON...BUT RETURNING TO IFR TOWARD 06Z TUESDAY. EXTENDED OUTLOOK...DETERIORATING CONDITIONS TUESDAY...WITH SHOWERS AND INTERMITTENT IFR CONDITIONS THROUGH THE EXTENDED. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 1230 AM MONDAY...BUMPED WIND SPEEDS UP TO 20-25 KT BASED ON BUOY DATA AND WIND OBSERVATIONS FROM MERCER PIER AT WRIGHTSVILLE BEACH AND A MESONET OBSERVATION FROM TOPSAIL BEACH. OTHERWISE NO SIGNIFICANT CHANGES WERE MADE WITH THIS UPDATE. DISCUSSION FROM 1000 PM SUNDAY FOLLOWS... SMALL CRAFT ADVISORY FOR NORTHERN WATERS AMZ250...CONTINUED INTO EARLY MON MORNING WITH HIGHEST SEAS IN THE NORTHERN OUTER WATERS. SCEC WILL CONTINUE CAPE FEAR TO LITTLE RIVER FORE SEAS INVOF 5 FT AT 20 NM. WHILE 15 TO 20 KT WINDS ARE POSSIBLE NORTHERN WATERS UNTIL AROUND MIDNIGHT...NE WINDS SHOULD DIMINISH TO 10 TO 15 KT OVER ALL WATERS BY DAYBREAK. SEAS SHOULD FALL BELOW SCA OR SCEC LEVELS LATE TONIGHT OR EARLY MONDAY. SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/... AS OF 300 PM SUNDAY...PERSISTENT COASTAL TROUGH WILL BE IN PLACE MON THEN SLOWLY LIFT OUT DURING TUE. THE EASTERLY FLOW AROUND STRONG NEW ENGLAND HIGH PRESSURE LOOKS LIKE IT SHOULD WEAKEN MON AS THE TIGHTER PRESSURE GRADIENT PROPAGATES NORTH. THE LOW-LEVEL FLOW IS EXPECTED TO BECOME MORE SOUTHERLY DURING TUE AND TUE NIGHT...BUT THE FLOW WILL BE WEAK. THE 10 TO 11 SECOND EASTERLY SWELL WILL REMAIN SIGNIFICANT INTO TUE AND THIS WILL KEEP SEAS ELEVATED. HOWEVER...THE WEAKER WINDS SHOULD ALLOW SEAS TO DROP ABOUT A FOOT OR SO. WIND SPEEDS THROUGH THE PERIOD WILL BE 10 KT OR LESS. SEAS UP TO 4 TO 5 FT ACROSS THE NORTHERN WATERS AND 3 TO 4 FT ACROSS THE SOUTHERN WATERS MON WILL DROP TO 2 TO 4 FT THROUGHOUT BY TUE. LONG TERM /WEDNESDAY THROUGH FRIDAY/... AS OF 300 PM SUNDAY...LIGHT WIND FIELDS EARLY ON WILL GIVE WAY TO A BETTER DEFINED NORTHEAST FLOW LATE WEDNESDAY. ESSENTIALLY LIGHT AND VARIABLE WINDS THROUGH EARLY AFTERNOON WEDNESDAY BEFORE A FRONT CROSSES THE WATERS. BEYOND THIS A NORTHEAST FLOW OF 10-15 KNOTS DEVELOPS AND STRENGTHENS TO 15-20 BY THURSDAY. THIS WILL CONTINUE INTO FRIDAY. SIGNIFICANT SEAS WILL INCREASE FROM 2-4 FEET WEDNESDAY TO 4-7 FEET LATER THURSDAY AND CONTINUE THROUGH THE DAY FRIDAY. && .TIDES/COASTAL FLOODING... AS OF 300 PM SUNDAY...A COASTAL FLOOD ADVISORY WILL BE ISSUED FOR A FEW HOURS THIS EVENING SURROUNDING PERIOD OF THE HIGH TIDE. THIS WILL IMPACT THE BEACHES FROM SURF CITY TO THE SOUTH SANTEE RIVER AND ALONG THE CAPE FEAR RIVER IN DOWNTOWN WILMINGTON. PERSISTENT ON SHORE WINDS AND LONG PERIOD EASTERLY SWELLS ALONG WITH HIGH ASTRONOMICAL TIDES HAVE RAISED TIDAL LEVELS TO GREATER THAN A FOOT ABOVE NORMAL. WE CAN EXPECT THIS TO PERSIST AT LEAST THROUGH THE NEXT DAY OR SO...BUT SLOWLY WANE AS WE PASS THE FULL MOON TONIGHT. THE NEXT HIGH TIDE FOR LOCAL BEACHES WILL BE BETWEEN 7 AND 8 PM THIS EVENING AND FOR THE CAPE FEAR RIVER IT WILL OCCUR AROUND 10 PM. THIS WILL COINCIDE VERY CLOSELY WITH THE FULL MOON AT 1050 PM THIS EVENING. THERE IS ALSO A HIGH RISK OF RIP CURRENTS FOR PENDER AND NEW HANOVER COUNTY BEACHES INTO TONIGHT AND FOR ALL BEACHES ON MONDAY. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...HIGH RIP CURRENT RISK FROM 8 AM EDT THIS MORNING THROUGH THIS EVENING FOR SCZ054-056. NC...HIGH RIP CURRENT RISK FROM 8 AM EDT THIS MORNING THROUGH THIS EVENING FOR NCZ106-108-110. MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EDT EARLY THIS MORNING FOR AMZ250. && $$ SYNOPSIS... NEAR TERM...TRA SHORT TERM...RJD LONG TERM...SHK AVIATION...TRA/DL
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
327 AM EDT MON SEP 28 2015 .SYNOPSIS... HIGH PRESSURE IS OFF THE COAST AND WINDS ARE MORE SOUTHERLY. A COLD FRONT WILL PUSH SOUTH ACROSS PENNSYLVANIA LATE TUESDAY...THEN STALL OUT SOUTH OF THE STATE. A SLOW MOVING COASTAL LOW WILL AFFECT PORTIONS OF THE MID ATLANTIC REGION LATE IN THE WEEK. COOLER TEMPERATURES WILL PREVAIL FOR THE SECOND PART OF THE WEEK. && .NEAR TERM /UNTIL 7 AM THIS MORNING/... WEAK SHORTWAVE RIDING ACROSS THE GRT LKS IS SUPPORTING AN AREA OF RAIN ACROSS NW PA AT 06Z. RADAR TRENDS AND LATEST HRRR IMPLY THE RAIN WILL TAPER OFF TOWARDS DAWN ACROSS THE NW COUNTIES...AS SHORTWAVE LIFTS OUT. HOWEVER...PLUME OF ANOMALOUS PWATS WILL REMAIN OVR THE WESTERN HALF OF THE STATE...SUPPORTING THE CHC OF LINGERING SHOWERS ACROSS THE NW MTNS THRU MID MORNING AND SPOTTY DRIZZLE WHERE MOIST SE FLOW ASCENDS THE LAUREL HIGHLANDS. WILL MAINTAIN A DRY OVERNIGHT FCST ACROSS THE EASTERN HALF OF THE STATE...WHERE SFC RIDGE AND LOWER PWAT AIR MASS WILL LIE. MAINLY OVERCAST SKIES AND INCREASING LOW LVL MOISTURE WILL TRANSLATE TO A MILDER NIGHT THAN LAST NIGHT WITH MIN TEMPS BTWN 55-60F. && .SHORT TERM /7 AM THIS MORNING THROUGH 6 PM TUESDAY/... OFFSHORE HIGH RETREATS FARTHER OFFSHORE ON MONDAY...WITH EASTERLY FETCH DECREASING AS A RESULT. DEEP LAYER MOISTURE PLUME INCREASES OVER PA AS A RESULT OF THE AMPLIFIED SOUTHERLY FLOW ALOFT. FORCING REMAINS WEAK ON MONDAY...BUT THE SERLY LOW LVL FLOW AND ASSOC OROGRAPHIC FORCING WILL KEEP THINGS CLOUDY FOR MOST. WEAK UPPER TROF LIFTING THRU WILL PRODUCE SCT SHOWERS...ESP ACROSS THE WEST. HIGHS WILL RANGE FROM THE MID TO UPPER 60S OVR THE ALLEGHENY PLATEAU TO THE U70S SOUTHEAST. && .LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/... MID SHIFT DID EDGE POPS UP SOME FOR THE LATER PART OF THE WEEK. THUS DID NOT MAKE ANY LARGE CHANGES TO THIS PART OF THE FCST. MAIN CHANGE WAS TO EDGE POPS DOWN JUST A LITTLE ON THE WESTERN AND NORTHERN EDGES. FIRST PROBLEM IS THE COLD FRONT FOR LATE TUE. DID UP POPS TO LIKELY. AS NOTED YESTERDAY...KEY TO FCST THE RATHER DRY AIR BEING ADVECTED INTO THE AREA THE LAST FEW DAYS. ANYWAY...NOT SOLD ON A LOT OF RAIN. MODELS HINT AT SOME MODERATE QPF. WILL HAVE TO ADVECT HIGHER DEWPOINT/PW AIR IN FROM THE SE COAST TO GET MUCH RAIN. LEFT THUNDER OUT FOR NOW. LATER WED AND THU STILL LOOK MAINLY DRY. FOR FRIDAY AND SAT...MODELS SHOW A LOW BACKING IN FROM THE COAST...AND A STRONG EASTERLY FLOW BETWEEN A LARGE HIGH OVER EASTERN CANADA AND THE LOW TO THE SOUTH. LOOKS LIKE THE MODELS TRY TO PHASE THE LONGWAVE ENERGY WITH A WARM CORE LOW. A LOT OF SPREAD IN SOLUTIONS FROM DAY TO DAY. LOOKS LIKE THE TIMING WOULD TAKE THE BULK OF THE RAIN TO THE NE BY LATER SAT. FOR NOW...LEFT SUNDAY DRY. NOT LOOKING AT FROST AT THIS POINT...BUT SOME RATHER COLD AIR WELL NORTH OF PA WITH SFC HIGH. ALTHOUGH MUCH UNCERTAINTY REMAINS WITH REGARDS TO LATE WEEK RAIN...THERE IS A GOOD DEAL OF CONFIDENCE IN TEMPS TAKING TUMBLE AFTER A VERY MILD MON-TUE. NORTHERLY FLOW/LOW LVL CAA IN WAKE OF COLD FRONT...COMBINED WITH POSSIBLE RAIN...SHOULD TRANSLATE TO TEMPS AOB CLIMO LATE NEXT WEEK...ESP DURING THE DAYTIME. && .AVIATION /07Z MONDAY THROUGH FRIDAY/... LLVL MOISTURE WILL SLOWLY INCREASE OVERNIGHT THROUGH THE DAY MONDAY AS THE FLOW CONTINUES TO BECOME MORE SOUTHERLY IN THE LOWEST 5KFT AGL. A LAYER OF DRY AIR WILL REMAIN ABOVE THAT. RESTRICTIONS FROM AN EXPANDING/LOWERING DECK OF STRATOCU AND STRATUS IMPACTING ALL OF CENTRAL PA AT 07Z. THE CLOUDS WILL CONTINUE TO GRADUALLY LOWER FROM SW TO NE OVERNIGHT...WITH MOST NUMEROUS -SHRA AFFECTING PRIMARILY THE NW THIRD OF CWA...WITH MORE ISOLATED -SHRA DRIFTING ACROSS THE SW. AREAS OF IFR CIGS /WITH SOME DRIZZLE OR SCATTERED -SHRA/ WILL OCCUR ACROSS THE CENTRAL AND WRN MTNS OF PENN LATE TONIGHT AND MONDAY MORNING...ESPECIALLY INVOF KJST WHERE THE SERLY LLVL UPSLOPE FLOW IS MAXIMIZED. SURFACE WINDS WILL BE FROM THE EAST TO SOUTHEAST AT SPEEDS OF GENERALLY 5-10MPH. LOW CIGS PERSIST INTO MON...WITH BEST CHANCE FOR IMPROVEMENT BEING OVER THE LOWER SUSQ. CONDITIONS COULD STAY IN THE LOW MVFR /OR EVEN UPPER IFR/ RANGE FOR MUCH OF THE DAY ACROSS NW HALF OF OUR FCST AREA WITH LIGHT RAIN SHOWERS AROUND. OUTLOOK... MON...INCREASING LIKELIHOOD OF LIGHT RAIN/LOW CIGS...FOCUSED MAINLY ACROSS WESTERN MTNS OF PENN. TUE...LOW CIGS/SHOWERS LIKELY...ESP NW HALF. TUE NIGHT...LOW CIGS/SCT SHOWERS. WED...LOW CIGS NW MTNS EARLY. CHC SHOWERS SOUTH. THU...NO SIG WX. FRI...CHC OF SHOWERS. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...DEVOIR/MARTIN NEAR TERM...FITZGERALD SHORT TERM...DEVOIR/FITZGERALD LONG TERM...FITZGERALD/MARTIN AVIATION...RXR
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
220 AM EDT MON SEP 28 2015 .SYNOPSIS... HIGH PRESSURE IS OFF THE COAST AND WINDS ARE MORE-SOUTHERLY. A COLD FRONT WILL PUSH SOUTH ACROSS PENNSYLVANIA LATE TUESDAY...THEN STALL OUT SOUTH OF THE STATE. A SLOW MOVING COASTAL LOW WILL AFFECT PORTIONS OF THE MID ATLANTIC REGION LATE IN THE WEEK. COOLER TEMPERATURES WILL PREVAIL FOR THE SECOND PART OF THE WEEK. && .NEAR TERM /UNTIL 7 AM THIS MORNING/... WEAK SHORTWAVE RIDING ACROSS THE GRT LKS IS SUPPORTING AN AREA OF RAIN ACROSS NW PA AT 06Z. RADAR TRENDS AND LATEST HRRR IMPLY THE RAIN WILL TAPER OFF TOWARDS DAWN ACROSS THE NW COUNTIES...AS SHORTWAVE LIFTS OUT. HOWEVER...PLUME OF ANOMALOUS PWATS WILL REMAIN OVR THE WESTERN HALF OF THE STATE...SUPPORTING THE CHC OF LINGERING SHOWERS ACROSS THE NW MTNS THRU MID MORNING AND SPOTTY DRIZZLE WHERE MOIST SE FLOW ASCENDS THE LAUREL HIGHLANDS. WILL MAINTAIN A DRY OVERNIGHT FCST ACROSS THE EASTERN HALF OF THE STATE...WHERE SFC RIDGE AND LOWER PWAT AIR MASS WILL LIE. MAINLY OVERCAST SKIES AND INCREASING LOW LVL MOISTURE WILL TRANSLATE TO A MILDER NIGHT THAN LAST NIGHT WITH MIN TEMPS BTWN 55-60F. && .SHORT TERM /7 AM THIS MORNING THROUGH 6 PM TUESDAY/... OFFSHORE HIGH RETREATS FARTHER OFFSHORE ON MONDAY...WITH EASTERLY FETCH DECREASING AS A RESULT. DEEP LAYER MOISTURE PLUME INCREASES OVER PA AS A RESULT OF THE AMPLIFIED SOUTHERLY FLOW ALOFT. FORCING REMAINS WEAK ON MONDAY...BUT THE SERLY LOW LVL FLOW AND ASSOC OROGRAPHIC FORCING WILL KEEP THINGS CLOUDY FOR MOST. WEAK UPPER TROF LIFTING THRU WILL PRODUCE SCT SHOWERS...ESP ACROSS THE WEST. HIGHS WILL RANGE FROM THE MID TO UPPER 60S OVR THE ALLEGHENY PLATEAU TO THE U70S SOUTHEAST. && .LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/... MID SHIFT DID EDGE POPS UP SOME FOR THE LATER PART OF THE WEEK. THUS DID NOT MAKE ANY LARGE CHANGES TO THIS PART OF THE FCST. MAIN CHANGE WAS TO EDGE POPS DOWN JUST A LITTLE ON THE WESTERN AND NORTHERN EDGES. FIRST PROBLEM IS THE COLD FRONT FOR LATE TUE. DID UP POPS TO LIKELY. AS NOTED YESTERDAY...KEY TO FCST THE RATHER DRY AIR BEING ADVECTED INTO THE AREA THE LAST FEW DAYS. ANYWAY...NOT SOLD ON A LOT OF RAIN. MODELS HINT AT SOME MODERATE QPF. WILL HAVE TO ADVECT HIGHER DEWPOINT/PW AIR IN FROM THE SE COAST TO GET MUCH RAIN. LEFT THUNDER OUT FOR NOW. LATER WED AND THU STILL LOOK MAINLY DRY. FOR FRIDAY AND SAT...MODELS SHOW A LOW BACKING IN FROM THE COAST...AND A STRONG EASTERLY FLOW BETWEEN A LARGE HIGH OVER EASTERN CANADA AND THE LOW TO THE SOUTH. LOOKS LIKE THE MODELS TRY TO PHASE THE LONGWAVE ENERGY WITH A WARM CORE LOW. A LOT OF SPREAD IN SOLUTIONS FROM DAY TO DAY. LOOKS LIKE THE TIMING WOULD TAKE THE BULK OF THE RAIN TO THE NE BY LATER SAT. FOR NOW...LEFT SUNDAY DRY. NOT LOOKING AT FROST AT THIS POINT...BUT SOME RATHER COLD AIR WELL NORTH OF PA WITH SFC HIGH. ALTHOUGH MUCH UNCERTAINTY REMAINS WITH REGARDS TO LATE WEEK RAIN...THERE IS A GOOD DEAL OF CONFIDENCE IN TEMPS TAKING TUMBLE AFTER A VERY MILD MON-TUE. NORTHERLY FLOW/LOW LVL CAA IN WAKE OF COLD FRONT...COMBINED WITH POSSIBLE RAIN...SHOULD TRANSLATE TO TEMPS AOB CLIMO LATE NEXT WEEK...ESP DURING THE DAYTIME. && .AVIATION /06Z MONDAY THROUGH FRIDAY/... LLVL MOISTURE WILL SLOWLY INCREASE OVERNIGHT...THROUGH THE DAY MONDAY AS THE FLOWS GRADUALLY VEERS FROM FROM EASTERLY TO SOUTHERLY WITHIN ABOUT THE LOWEST 5 KFT AGL. THIS WILL MAINTAIN LAYERS OF DRY AIR ABOVE THE OTHERWISE EXPANDING/LOWERING DECK OF STRATO CU AND STRATUS. THE CURRENT MAINLY MVFR STRATO CU/STRATUS DECK EXTENDING FROM KBFD TO KUNV AND KAOO HAS LOWERED TO IFR ACROSS THE LAUREL HIGHLANDS. THE CLOUDS WILL CONTINUE TO GRADUALLY LOWER FROM SW TO NE OVERNIGHT WITH ISOLATED TO SCATTERED -SHRA AFFECTING PRIMARILY THE SWRN THIRD-HALF OF PENN. AREAS OF IFR CIGS /WITH SOME DRIZZLE OR SCATTERED -SHRA/ WILL OCCUR ACROSS THE CENTRAL AND WRN MTNS OF PENN LATE TONIGHT AND MONDAY MORNING...ESPECIALLY INVOF KJST WHERE THE SERLY LLVL UPSLOPE FLOW IS MAXIMIZED. SURFACE WINDS WILL BE FROM THE EAST TO SOUTHEAST AT SPEEDS OF GENERALLY 5-10MPH. LOW CIGS PERSIST INTO MON...WITH BEST CHANCE FOR IMPROVEMENT BEING OVER THE LOWER SUSQ. CONDITIONS COULD STAY IN THE LOW MVFR /OR EVEN UPPER IFR/ RANGE FOR MUCH OF THE DAY ACROSS NW HALF OF OUR FCST AREA WITH LIGHT RAIN SHOWERS AROUND. OUTLOOK... MON...INCREASING LIKELIHOOD OF LIGHT RAIN/LOW CIGS...FOCUSED MAINLY ACROSS WESTERN MTNS OF PENN. TUE...LOW CIGS/SHOWERS LIKELY...ESP NW HALF. TUE NIGHT...LOW CIGS/SCT SHOWERS. WED...LOW CIGS NW MTNS EARLY. CHC SHOWERS SOUTH. THU...NO SIG WX. FRI...CHC OF SHOWERS. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...DEVOIR/MARTIN NEAR TERM...FITZGERALD SHORT TERM...DEVOIR/FITZGERALD LONG TERM...FITZGERALD/MARTIN AVIATION...LAMBERT/MARTIN
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
320 AM CDT MON SEP 28 2015 .SHORT TERM...IT WAS A MOSTLY CLOUDY AND MUGGY NIGHT ACROSS MID TN...WITH A FEW LIGHT SHOWERS OVER THE PLATEAU. WX FEATURES WE ARE WATCHING FOR THIS FORECAST INCLUDE AN UPPER LEVEL LOW PRESSURE SYSTEM ALONG THE TX GULF COAST...AND A TROPICAL LOW OVER THE GULF OF MEXICO. SATELLITE AND RADAR LOOPS SHOWED DEEP TROPICAL MOISTURE AND SHOWERS STREAMING NORTHWARD FROM THE GULF. FOR TODAY...CLOUDS WILL THICKEN AND THE COVERAGE OF SHOWERS WILL INCREASE THROUGH THE DAY...ESPECIALLY FOR OUR SOUTHERN COUNTIES. HIGHS WILL RANGE IN THE UPPER 70S TO LOWER 80S WITH MUGGY DEW POINTS IN THE 60S. FOR TONIGHT THROUGH TUESDAY...A SURGE OF DEEP TROPICAL MOISTURE WILL PUSH INTO TN. PRECIPITABLE WATER VALUES WILL REACH AROUND 2 INCHES BY TUESDAY MORNING. AT THE SAME TIME...IMPULSES WILL LIFT NORTHWARD AHEAD OF THE TX UPPER LEVEL LOW...AND A DISTURBANCE WILL APPROACH FROM THE NORTHWEST. THE TROPICAL LOW WILL TRACK ACROSS NORTH FL TOWARD THE CAROLINA COAST...BUT MOISTURE WITH THIS SYSTEM WILL SPREAD WELL NWWD TO THE TN VALLEY. THESE INGREDIENTS WILL LEAD TO WIDESPREAD SHOWERS AND A FEW THUNDERSTORMS LATE TONIGHT THROUGH TUESDAY. AVERAGE RAINFALL AMOUNTS THROUGH TUESDAY ARE EXPECTED TO RANGE FROM AROUND ONE HALF INCH OVER OUR NORTHWEST COUNTIES TO MORE THAN 1 INCH OVER THE SOUTH. LOCALLY GREATER AMOUNTS WITH HEAVY DOWNPOURS ARE LIKELY OVER THE SOUTH AND PLATEAU AS WELL. UPPER LEVEL WINDS WILL TURN NORTHWEST TUESDAY NIGHT INTO WEDNESDAY WITH A COLD FRONT PASSAGE. THE COVERAGE AND INTENSITY OF SHOWERS WILL DECREASE. .LONG TERM...COOLER AIR WILL MOVE IN FOR THE EXTENDED FORECAST. OVERNIGHT LOWS WILL BE DIPPING INTO THE 50S WITH HIGHS MAINLY IN THE UPPER 60S TO LOWER 70S...WHICH WOULD BE JUST A COUPLE OF DEGREES COOLER THAN NORMAL. MODELS SUGGEST AN UPPER TROUGH WILL LINGER...POSSIBLY KEEPING SOME SHOWERS AROUND FOR THE UPPER CUMBERLAND REGION LATE WEEK THROUGH THE WEEKEND. ANOTHER SYSTEM MAY BRING SCATTERED SHOWERS ACROSS THE AREA INTO EARLY NEXT WEEK...BUT CONFIDENCE IS LOW REGARDING THE DETAILS. 13 && .PREV DISCUSSION... /ISSUED 1142 PM CDT SUN SEP 27 2015/ AVIATION UPDATE... RAIN ACTIVITY HAS BEEN UNDERWHELMING THIS EVENING AND HRRR DOES NOT PAINT A WET PICTURE FOR THE REST OF THE OVERNIGHT HOURS. TOOK OUT VCSH AT ALL THREE TERMINALS UNTIL MORNING WHERE GUIDANCE BUMPS POPS SLIGHTLY. BR WILL BE AN ISSUE AT CKV AND CSV OVERNIGHT. THE MORE SIGNIFICANT OMEGA AND RAIN CHANCES WILL HOLD OFF UNTIL AFTER THE END OF THE TAF PERIOD. WINDS WILL BE E/SE UNDER 5 KTS DURING THE TAF PERIOD. && .PRELIMINARY POINT TEMPS/POPS... NASHVILLE 81 66 78 65 / 40 80 90 50 CLARKSVILLE 81 66 78 63 / 30 60 80 40 CROSSVILLE 77 64 74 63 / 30 80 100 60 COLUMBIA 80 65 79 65 / 40 80 90 50 LAWRENCEBURG 79 65 79 65 / 50 80 90 50 WAVERLY 81 65 79 64 / 30 70 80 40 && .OHX WATCHES/WARNINGS/ADVISORIES...NONE. && $$
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
1142 PM CDT SUN SEP 27 2015 .AVIATION UPDATE... RAIN ACTIVITY HAS BEEN UNDERWHELMING THIS EVENING AND HRRR DOES NOT PAINT A WET PICTURE FOR THE REST OF THE OVERNIGHT HOURS. TOOK OUT VCSH AT ALL THREE TERMINALS UNTIL MORNING WHERE GUIDANCE BUMPS POPS SLIGHTLY. BR WILL BE AN ISSUE AT CKV AND CSV OVERNIGHT. THE MORE SIGNIFICANT OMEGA AND RAIN CHANCES WILL HOLD OFF UNTIL AFTER THE END OF THE TAF PERIOD. WINDS WILL BE E/SE UNDER 5 KTS DURING THE TAF PERIOD. && .PREV DISCUSSION... /ISSUED 842 PM CDT SUN SEP 27 2015/ UPDATE... WEAK ISENTROPIC UPGLIDE WILL KEEP CLOUDS AND LIGHT SHOWER CHANCES GOING THROUGH THE OVERNIGHT AND DURING THE DAY MONDAY. CURRENTLY SPOTTY LIGHT SHOWERS ARE CONTINUING TO WORK NORTHWARD FROM ALABAMA INTO MIDDLE TENNESSEE. LOOKS LIKE CLOUDS WILL ALSO CONTINUE TO THICKEN UP AS WE GO THROUGH THE EVENING AND OVERNIGHT...THEREFORE IT DOESNT LOOK GOOD FOR ECLIPSE VIEWING. TEMPS SHOULD BE IN THE LOW TO MIDDLE 60S FOR OVERNIGHT MINS. && .PRELIMINARY POINT TEMPS/POPS... NASHVILLE 66 81 67 81 / 30 30 30 60 CLARKSVILLE 64 81 65 81 / 20 20 30 60 CROSSVILLE 63 76 64 74 / 30 30 60 70 COLUMBIA 65 80 65 79 / 40 30 40 60 LAWRENCEBURG 65 79 66 78 / 40 40 40 60 WAVERLY 65 81 65 80 / 20 20 30 60 && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 10
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
157 AM EDT MON SEP 28 2015 .SYNOPSIS... A COMPLEX AREA OF LOW PRESSURE ACROSS THE REGION WILL MAINTAIN A STRONG ONSHORE FLOW OF MOISTURE INTO THE AREA OVERNIGHT. THIS WILL COMBINE WITH A STRONG WEDGE OF HIGH PRESSURE ALONG THE APPALACHIANS AND LEAD TO CONTINUED WIDESPREAD RAIN OR DRIZZLE UNDER GUSTY NORTHEAST WINDS AND COOL TEMPERATURES. WEAK HIGH PRESSURE WILL BUILD INTO THE AREA ON MONDAY...BEFORE LOW PRESSURE APPROACHES FROM THE GULF COAST REGION BY MIDWEEK...POSSIBLY BRINGING ANOTHER ROUND OF HEAVIER RAINFALL BY TUESDAY. && .NEAR TERM /THROUGH TODAY/... AS OF 951 PM EDT SUNDAY... HIGH PRESSURE REMAINS WEDGED AGAINST THE EASTERN SLOPES OF THE APPALACHIANS TONIGHT...MAINTAINING A COOL NORTHEAST WIND. AT THE SAME TIME...LOW PRESSURE OFF THE COAST CONTINUES TO PUSH DEEP MOISTURE INTO THE HIGHER TERRAIN. PERIODS OF RAIN...DRIZZLE AND FOG WILL CONTINUE OVERNIGHT INTO MONDAY MORNING. HEAVIER BANDS OF RAIN ARE DEVELOPING AND LIFT NORTH. RAINFALL OVERNIGHT WILL BE ENHANCE ALONG THE BLUE RIDGE WITH THE HEAVIEST AMOUNTS EXPECTED ALONG THE SOUTHERN BLUE RIDGE. ADJUSTED TEMPERATURES THIS EVENING INTO TONIGHT WITH THE LATEST OBS AND MODEL TRENDS. TEMPERATURES RUNNING COOLER IN SEVERAL AREAS THIS EVENING WITH RAIN AND CLOUDS. SHAPED THE NEXT COUPLE OF HOURS FOR POPS TOWARDS HIRESW-ARW- EAST...RUC AND HRRR WITH THE AXIS ON THE WEST. INCREASED QPF FOR TONIGHT ALONG SOUTHERN BLUE RIDGE AND WESTERN MOUNTAINS. WITH SATURATED GROUNDS...WE WILL HAVE TO WATCH FOR LOCALIZED FLOODING ISSUES OVERNIGHT INTO MONDAY MORNING. AS OF 650 PM EDT SUNDAY... MADE SOME MINOR ADJUSTMENTS IN TEMPERATURES AND DEW POINTS FOR THIS EVENING INTO TONIGHT. AS OF 330 PM EDT SUNDAY... FOR THIS EVENING AND TONIGHT...EXPECT LITTLE CHANGE FROM CURRENT CONDITIONS AS HIGH PRESSURE REMAINS WEDGED AGAINST THE EASTERN FACE OF THE APPALACHIANS...MAINTAINING A COOL NORTHEAST WINDFLOW ACROSS THE MID ATLANTIC. AT THE SAME TIME...LOW PRESSURE OFF THE COAST CONTINUES TO PUSH DEEP MOISTURE INTO THE HIGHER TERRAIN... RESULTING IN WIDESPREAD LOW CLOUDS AND SCATTERED BANDS OF RAIN. RAIN WILL CONTINUE AREAWIDE...REMAINING HEAVIEST/MOST PERSISTENT IN THE VICINITY OF THE BLUE RIDGE WHERE THE UPSLOPE CONDITIONS WILL AMPLIFY RAINFALL INTENSITY. AS SUCH...MAY SEE AN ADDITIONAL ONE TO TWO INCHES OF RAINFALL NEAR THE BLUE RIDGE PARKWAY THROUGH MONDAY MORNING. THE DEEP MOISTURE AND LOW CLOUDS WILL NOT ALLOW FOR MUCH COOLING OVERNIGHT HOWEVER...WITH OVERNIGHT LOWS EXPECTED TO RANGE FROM THE UPPER 50S TO THE LOW 60S. RAINFALL WILL BE MORE SPOTTY ON MONDAY AS HIGH PRESSURE WEDGING WEAKENS...AND ONSHORE FLOW OF MOISTURE DIMINISHES...MAKING MOISTURE MORE SHALLOW ACROSS OUR AREA. THAT STATED...EXPECT WE WILL STILL SEE SPOTTY BANDS OF RAIN MAKE THEIR WAY ACROSS THE AREA FROM THE COAST. WITH THE CONTINUED UPSLOPE FLOW...PERSISTENT AND OCCASIONALLY HEAVY RAINFALL CAN AGAIN BE EXPECTED ALONG THE BLUE RIDGE AND OTHER EAST FACING SLOPES. NEEDLESS TO SAY...DO NOT EXPECT WE WILL SEE CLOUDS BREAK OUT ANYWHERE OUTSIDE OF WESTERN TAZEWELL COUNTY...WHERE A FEW RAYS OF SUNSHINE MAY BE POSSIBLE DURING THE AFTERNOON. REGARDLESS...WITH LESS RAINFALL EXPECTED... BELIEVE AFTERNOON TEMPERATURES WILL BE WARMER...ALTHOUGH BELOW THE COOLER MAV GUIDANCE. MONDAY AFTERNOON HIGHS WILL RANGE FROM THE LOW/MID 60S ALONG THE RIDGES...TO THE LOW 70S ACROSS THE PIEDMONT. && .SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/... AS OF 330 PM EDT SUNDAY... OVERALL PATTERN DOES NOT CHANGE APPRECIABLY IN THE EARLY TO MID-WEEK PATTERN WITH UPPER LEVEL TROUGH TO THE WEST MAINTAINING VERY MOIST SOUTHERLY FLOW ALOFT INTO THE SOUTHERN APPALACHIANS AND MID-ATLANTIC REGION. HIGH PRESSURE OVER SOUTHEAST CANADA WILL ALSO KEEP SOME SEMBLANCE OF A WEDGE ACROSS THE AREA WITH EAST TO NORTHEAST FLOW IN THE LOWER LEVELS. SUN SEEKERS SHOULD DEFINITELY LOOK ELSEWHERE AS OVERCAST SKIES AND CHANCES FOR RAINFALL ARE VERY LIKELY TO PERSIST RIGHT INTO MID-WEEK AND BEYOND. A SLOW-MOVING COLD FRONT OVER THE MIDWEST AT THE OUTSET OF THE PERIOD WILL PUSH SLOWLY SOUTHEAST AND ACROSS THE FORECAST AREA TUESDAY...WITH INCREASING CHANCES FOR ORGANIZED RAINFALL AHEAD OF AND ALONG THE FRONT TUESDAY INTO WEDNESDAY. MODEL QPFS PER EURO/GFS RANGE FROM 1 TO 3+ INCHES FROM LATE MONDAY INTO LATE WEDNESDAY WHICH SUGGESTS A POSSIBILITY FOR RIVER FLOODING (SEE HYDRO SECTION BELOW) ACROSS BASINS WHICH HAVE BECOME MUCH MORE SATURATED WITH THIS WEEKENDS RAINFALL. TEMPS WILL HAVE NARROW DIURNAL RANGES DURING THE PERIOD WITH THE EXTENSIVE CLOUD COVER MAINLY FROM UPPER 50S/LOW 60S AT NIGHT TO UPPER 60S/LOW 70S IN THE DAY. && .LONG TERM /THURSDAY THROUGH SUNDAY/... AS OF 330 PM EDT SUNDAY... THE COLD FRONT SHOULD STALL OFF THE EAST COAST BY EARLY THURSDAY WITH ONE OR MORE WAVES OF LOW PRESSURE POSSIBLY DEVELOPING ALONG THIS BOUNDARY. TOO EARLY TO TELL EXACT POSITIONING AND EFFECTS OF ANY SUCH DEVELOPMENT...BUT 12Z GFS IS ACTUALLY QUITE WET ACROSS EVEN CENTRAL AND WESTERN CWA ON FRIDAY INTO EARLY SATURDAY SO AT LEAST CHANCE POPS ARE HELD IN THE GRIDS THROUGH SATURDAY ALTHOUGH STILL HAVE HIGHEST CHANCES IN THE EAST AND TRENDING TOWARD ONLY SLIGHT CHANCE IN THE FAR WEST. TEMPS SHOULD BE SLIGHTLY COOLER BEHIND THE FRONT WITH LOW 60S NW TO UPPER 60S SE FOR HIGHS AND MID 40S TO LOW 50S FOR LOWS. && .AVIATION /06Z MONDAY THROUGH FRIDAY/... AS OF 155 AM EDT MONDAY... POOR FLYING CONDITIONS EXPECTED TODAY AND TONIGHT. DEEP SOUTHEAST WINDS AROUND A HIGH CENTERED OFF OF THE NEW ENGLAND COAST WILL RESULT IN WIDESPREAD LIFR TO MVFR CEILINGS TODAY AND TONIGHT. AREAS OF DRIZZLE...FOG AND LIGHT RAIN ARE EXPECTED THROUGH MID MORNING WITH VISIBILITIES MAINLY IN THE MVFR RANGE. BUFKIT AND MODEL FORECASTS SHOWED A 30 TO 35 KNOT SOUTHEAST LOW LEVEL JET AT THE 06Z/2AM START OF THE TAF PERIOD OVER SOUTHEAST WEST VIRGINIA. HIGH CONFIDENCE OF OCCASIONAL WIND GUSTS OF 20 TO 25 KNOTS AT KBLF UNTIL 12Z WHEN THE JET BECOMES WEAKER. AFTER SUNRISE CEILINGS WILL GRADUALLY IMPROVE A FEW HUNDRED FEET AND AS THE SOUTHEAST UPSLOPE WINDS WEAKEN...FOG AND DRIZZLE WILL BECOME MORE PATCHY AND LESS WIDESPREAD. MODERATE CONFIDENCE AS TO HOW MUCH CEILINGS WILL RISE TODAY...ESPECIALLY AT KLYH/KROA AND KBCB. CEILINGS WILL LOWER AGAIN AFTER SUNSET BACK TO IFR AND LIFR VALUES. EXTENDED AVIATION DISCUSSION... ANOTHER STORM SYSTEM WILL APPROACH LATE TUESDAY...BRINGING ANOTHER ROUND OF POTENTIALLY HEAVY RAIN...AS WELL AS SUB VFR CEILINGS/VISIBILITIES INTO WEDNESDAY. A DEVELOPING WEDGE MAY KEEP MVFR CEILINGS IN PLACE FOR LATE IN THE WEEK. && .HYDROLOGY... AS OF 345 PM EDT SUNDAY... SMALLER STREAMS AND CREEKS HAVE CRESTED FOR THE MOST PART WITH NOTHING HAVING REACHED EVEN ACTION STAGE DESPITE WIDESPREAD 1 TO 4 INCHES IN 72 HOURS AND UP TO 8 OR MORE INCHES OF IN ISOLATED PARTS OF THE BLUE RIDGE. THE HEAVIEST RAIN FELL IN THE UPPER REACHES OF THE DAN AND SMITH RIVER BASINS AND WHATEVER RUNOFF OCCURRED WILL BE MAKING ITS WAY DOWNSTREAM. PHILPOTT RESERVOIR CAUGHT A SUBSTANTIAL PORTION OF THE SMITH RIVER BASIN RUNOFF WITH THE RESERVOIR ELEVATION CLIMBING OVER 2 FEET OVER THE PAST TWO DAYS. FURTHER DOWNSTREAM THE DAN IS STILL RISING ALONG ITS ENTIRE REACH BUT IS STILL CURRENTLY FORECAST TO CREST BELOW ACTION STAGE EVEN AT FLOOD-PRONE SOUTH BOSTON. WITH MORE RAIN ON THE WAY SOME OF IT POSSIBLY HEAVY... ESPECIALLY TUESDAY INTO WEDNESDAY AND POSSIBLY AGAIN LATER IN THE WEEK IT WOULD BE PRUDENT TO PAY CLOSE ATTENTION TO RIVER FORECASTS AS THEY WILL LIKELY BE UPDATED FREQUENTLY. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ SYNOPSIS...NF NEAR TERM...KK/NF SHORT TERM...PC LONG TERM...AMS/PC AVIATION...AMS HYDROLOGY...JH/MBS
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
333 AM MDT MON SEP 28 2015 .SHORT TERM...(TODAY THROUGH WEDNESDAY NIGHT) ISSUED AT 325 AM MDT MON SEP 28 2015 CURRENT SURFACE OBS ACROSS THE AREA SHOW A WEAK COLD FRONT NEAR THE NORTH PLATTE RIVER VALLEY EXTENDING FROM NEAR DOUGLAS WYOMING SOUTHEAST INTO THE SOUTHERN NEBRASKA PANHANDLE. WINDS HAVE STARTED TO SHIFT INTO THE NORTHEAST ACROSS NIOBRARA COUNTY AND MOST OF THE NORTHERN NEBRASKA PANHANDLE. THE FRONT WILL STALL NEAR THE MOUNTAINS THIS AFTERNOON AND REMAIN NEARLY STATIONARY JUST WEST OF THE LARAMIE RANGE INTO TUESDAY. THE JET STREAM WILL BECOME MORE ACTIVE TODAY AS WELL...AS A 90 KNOT JET STREAK IS FORECAST TO PUSH ACROSS WYOMING TODAY. THE COMBINATION OF THE FRONT AND A MORE ACTIVE JET WILL SET THE STAGE FOR A BETTER CHANCE OF SHOWERS AND TSTORMS TODAY AND TUESDAY AS SOME LLVL INSTABILITY WILL BE PRESENT. EXPECT BANDS OF SHOWERS WITH EMBEDDED TSTORMS TO DEVELOP ACROSS THE MOUNTAINS OF CENTRAL WYOMING AND QUICKLY MOVE EASTWARD INTO THE HIGH PLAINS TODAY AND INTO TONIGHT...ESPECIALLY BETWEEN 3 PM AND MIDNIGHT TONIGHT WHEN MODELS INDICATE THE BEST LIFT ASSOCIATED WITH THE JET STREAK WILL BE OVER THE FORECAST AREA. WITH GOOD UPSLOPE FLOW AND A DECENT CHANCE OF RAINFALL...LOW STRATUS AND PATCHY FOG IS POSSIBLE LATE TONIGHT AND EARLY TUESDAY ALONG AND EAST OF THE LARAMIE RANGE. HIGH TEMPERATURES TODAY WILL BE 15 TO 20 DEGREES COOLER COMPARED TO SATURDAY/SUNDAY WITH HIGHS IN THE MID 60S TO MID 70S EXPECTED. TUESDAYS FORECAST WILL BE TRICKY SINCE MODELS INDICATE LOW STRATUS CLOUDS HANGING ON EAST OF THE LARAMIE RANGE THROUGH THE DAY. THIS MAY RESULT IN HIGH TEMPERATURES STRUGGLING TO REACH 60 DEGREES OVER MOST OF WESTERN NEBRASKA AND PORTIONS OF SOUTHEAST WYOMING TUESDAY AFTERNOON. JUST TO THE WEST...WINDS WILL GRADUALLY SHIFT INTO THE WEST ALLOWING SOME DRY AIR TO PUSH INTO THE AREA. HOWEVER...SUNSHINE WILL INCREASE LLVL INSTABILITY AND ALLOW SHOWERS AND TSTORMS TO REDEVELOP. KEPT POP BETWEEN 25 TO 40 PERCENT ACROSS THE MOUNTAINS FOR SHOWERS AND A FEW TSTORMS. MODEL SOUNDINGS DO SHOW AMPLE INSTABILITY ACROSS SOUTHEAST WYOMING WITH CAPE VALUES AROUND 1000 J/KG IN ADDITION TO MODERATE LOW TO MIDLEVEL SHEAR. WILL NEED TO WATCH AREAS ALONG AND WEST OF I25 FOR STRONG TSTORMS. FOR WEDNESDAY...MODELS ALL SHOW AN UPPER LEVEL RIDGE AXIS AMPLIFYING ALONG THE CONTINENTAL DIVIDE. LITTLE TO NO CHANCE OF CONVECTION DUE TO MIDLEVEL SUBSIDENCE AND DRIER AIR. HIGH TEMPERATURES WILL REBOUND INTO THE MID 70S TO LOW 80S ACROSS THE AREA...WARMEST JUST EAST OF THE LARAMIE RANGE. .LONG TERM...(THURSDAY THROUGH SUNDAY) ISSUED AT 236 AM MDT MON SEP 28 2015 MODELS HAVE COME INTO PRETTY GOOD AGREEMENT WITH REGARD TO THE STORM SYSTEM THAT WILL IMPACT THE REGION BY FRI/SAT. MIDLVL RIDGE AXIS WILL BE OVERHEAD ON THURS AND IT WILL LIKELY BE THE WARMEST DAY WITH HIGHS MOSTLY IN THE 70S. UPPER TROUGH WILL MOVE EASTWARD FROM THE GREAT BASIN ON THURS AND BE LOCATED NEAR WYOMING BY FRI. LLVL MOISTURE ADVECTION WILL OCCUR ON THURS NIGHT WITH SOUTHEASTERLY UPSLOPE WINDS ACROSS THE PLAINS. BOTH THE GFS AND ECMWF SHOW THE BEST UPPER LEVEL DIVERGENCE/LARGE SCALE ASCENT DURING THE DAY ON FRI. WITH CLOUDY SKIES AND RAINFALL OCCURRING...DROPPED HIGHS A FEW DEGREES ON FRI. SNOW COULD BE POSSIBLE IN THE HIGHEST MTNS ON FRI (ABOVE AROUND 11000 FT). THE GFS AND ECMWF BEGIN TO DIVERGE BY SAT. THE GFS WEAKENS THE UPPER TROUGH BUT DROPS IT SOUTHEAST INTO COLORADO. THIS KEEPS LIGHT PRECIP MAINLY FROM LLVL UPSLOPE GOING THROUGH THE DAY ALONG WITH COLD AIR ADVECTION (700MB TEMPS DROP TO -2C). THE ECMWF ON THE OTHER HAND IS PROGRESSIVE WITH THE TROUGH SWINGING INTO NEBRASKA. REGARDLESS OF THE SOLN IT WILL BE A RATHER COOL DAY WITH HIGHS STRUGGLING TO GET OUT OF THE MID 50S (EVEN COLDER ON THE GFS). HEIGHTS ALOFT RISE BY SUNDAY BUT IT WILL STILL BE COOL. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 1037 PM MDT SUN SEP 27 2015 VFR CONDITIONS FOR ALL SOUTHEAST WYOMING AND NEBRASKA PANHANDLE AIRPORTS TONIGHT INTO MONDAY MORNING. HRRR GUIDANCE BEGINNING TO INDICATE SOME FOG/IFR IN THE PLATTE RIVER VALLEY NEAR KBFF TOWARDS 12Z. NOT A FAVORABLE WIND DIRECTION THOUGH...SO DID NOT INCLUDE IN THE 06Z TAF FOR KBFF. WILL SEE A CHANGE THOUGH MONDAY AFTERNOON AS WE SEE NORTHEASTERLY UPSLOPING WINDS EAST OF THE LARAMIE RANGE. CONTINUED THE TREND DOWN ON CEILINGS MONDAY AFTERNOON. WILL LIKELY SEE IFR/LIFR CONDITIONS MONDAY EVENING FOR MUCH OF THE PANHANDLE AND AIRPORTS EAST OF THE LARAMIE RANGE THROUGH TUESDAY. && .FIRE WEATHER... ISSUED AT 236 AM MDT MON SEP 28 2015 FIRE WEATHER CONCERNS WILL BE LOW THROUGH THIS WEEK DUE TO RELATIVELY LIGHT WINDS AND DAYTIME HUMIDITIES ABOVE 20 PERCENT IN MOST LOCATIONS. WEDNESDAY WILL BE THE DRIEST DAY WITH DAYTIME RELATIVE HUMIDITIES POTENTIALLY LOWERING TO 15 PERCENT ACROSS SOUTHEAST WYOMING BEFORE A STRONG COLD FRONT MOVES ACROSS THE AREA LATE IN THE WEEK. WIDESPREAD WETTING RAINFALL AND MOUNTAIN SNOWS ARE POSSIBLE FRIDAY AND SATURDAY AS A PACIFIC STORM SYSTEM MOVES ACROSS THE AREA. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...NONE. NE...NONE. && $$ SHORT TERM...TJT LONG TERM...ZF AVIATION...GCC FIRE WEATHER...TJT
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1039 PM MDT SUN SEP 27 2015 .SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT) ISSUED AT 152 PM MDT SUN SEP 27 2015 LATEST SATELLITE IMAGERY SHOWS CLOUDS DEVELOPING THROUGH MOST OF SOUTHEASTERN WYOMING WITH THE SFC TROUGH MOVING CONTINUING TO MOVE TO THE EAST OUT OF THE CWA. CURRENTLY RADAR IS SHOWING SHOWERS/TSTORM STAYING WELL NORTH OF THE CWA...BUT POPS ARE POSSIBLE INTO THIS EVENING ESPECIALLY EAST OF THE LARAMIE RANGE AND INTO CONVERSE AND NIOBRARA COUNTIES. CLOUDS WILL LINGER INTO TONIGHT KEEPING TEMPERATURES SLIGHTLY WARMER. TOMORROW AN UPPER LEVEL JET OVER SOUTHERN WYOMING WILL PROVIDE SOME UPWARD MOTION INTO THE AFTERNOON AND EVENING HOURS. COMBINED WITH UPSLOPE FLOW FROM EASTERLY WINDS NEAR THE SURFACE COULD PRODUCE ISOLATED THUNDERSTORMS. GFS AND ECMWF SHOW AN INCREASE IN QPF OVER THE SIERRA MADRES AND SNOWY RANGES EARLY IN THE DAY AND THEN MOVING EASTWARD INTO THE NEBRASKA PANHANDLE. HIGHS TOMORROW WILL BE SLIGHTLY COOLER WITH CLOUDS KEEPING TEMPERATURES DOWN FOR MOST OF SOUTHEASTERN WYOMING AND THE NEBRASKA PANHANDLE. ALTHOUGH...WEST OF THE LARAMIE RANGE TEMPERATURES ARE EXPECTED TO BE WARMER WITH CLEARER SKIES. SOME STRATUS CLOUDS COULD DEVELOP MONDAY NIGHT OVER THE NEBRASKA PANHANDLE MOVING DOWN FROM THE NORTH WITH THE PASSAGE OF A WEAK FRONTAL BOUNDARY. TUESDAY CLOUDS WILL REMAIN OVER WESTERN WYOMING AND THE NEBRASKA PANHANDLE INTO THE AFTERNOON. POPS WILL DECREASE WITH A STABLE AIRMASS SLIDING INTO THE CWA. .LONG TERM...(WEDNESDAY THROUGH SUNDAY) ISSUED AT 152 PM MDT SUN SEP 27 2015 WEDNESDAY-THURSDAY: THE MODELS ARE IN PRETTY GOOD AGREEMENT DURING THIS TIMEFRAME WITH THE UPPER LEVEL RIDGE SNEAKING IN BETWEEN THE UPPER LEVEL TROF IN THE EAST AND THE TROF IN THE PACIFIC NORTHWEST. THIS WILL CONTINUE TO PROVIDE MILD CONDITIONS TO THE AREA WITH LITTLE OR NO CHANCES OF PRECIP. THE WIND IS EXPECTED TO BE LIGHT AND VARIABLE ON WEDNESDAY...BUT THE WIND/DEWPOINTS WILL BEGIN TO INCREASE FROM THE EAST-SOUTHEAST ON THURSDAY AS THE PACIFIC UPPER LEVEL WAVE APPROACHES IDAHO AND NORTHERN UTAH. FRIDAY-SUNDAY: LOTS OF UNCERTAINTY ON HOW THINGS ARE GOING TO PAN OUT DURING THIS TIMEFRAME. THE MAIN QUESTION WILL BE WHETHER OR NOT THIS PACIFIC TROF WILL SHEAR OUT AS IT MOVES INTO THE ROCKIES. CURRENTLY...THE CANADIAN SOLUTION IS PROGGING THIS WAVE TO LIFT NORTHEAST INTO NORTHERN PLAINS FRIDAY INTO SATURDAY. THE ECMWF/GFS SOLUTIONS ARE SHOWING THE WAVE STALLING OVER WYOMING/NORTHERN COLORADO/WESTERN NEBRASKA AND THEN SPENDING MOST OF ITS TIME BRINGING BENEFICIAL RAINFALL TO THE AREA FRIDAY AND SATURDAY. MEANWHILE...THE GEFS/NAEFS SOLUTIONS ARE SHOWING THE WAVE LIFTING NORTHEAST TO THE NORTHERN PLAINS SIMILAR TO THE CANADIAN SOLUTION WHICH MAY KEEP THE BEST CHANCES OF RAIN IN OUR NORTHERN ZONES. AT THIS POINT...WE ARE FAVORING THE ENSEMBLE APPROACH WHICH KEEPS THE BEST CHANCES OF PRECIP. ALONG AND NORTHEAST OF A DOUGLAS TO SCOTTSBLUFF LINE. THIS MAY ALSO BRING MORE WIND TO THE AREA IF THIS SYSTEM STAYS FURTHER NORTH. HOWEVER...IF THIS SYSTEM DIGS FURTHER SOUTH AS THE GFS SUGGESTS WE MAY END UP WITH VERY COOL AND RAINY CONDITIONS THIS WEEKEND WITH PERHAPS SOME SNOW IN THE MOUNTAINS. REGARDLESS OF WHERE THE TRACK IS...CLOUDY AND COOLER CONDITIONS ARE ON TAP FOR THIS WEEKEND WITH HIGHS IN THE LOW TO MID 60S WITH EVEN 50S IN THE LARAMIE RANGE. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 1037 PM MDT SUN SEP 27 2015 VFR CONDITIONS FOR ALL SOUTHEAST WYOMING AND NEBRASKA PANHANDLE AIRPORTS TONIGHT INTO MONDAY MORNING. HRRR GUIDANCE BEGINNING TO INDICATE SOME FOG/IFR IN THE PLATTE RIVER VALLEY NEAR KBFF TOWARDS 12Z. NOT A FAVORABLE WIND DIRECTION THOUGH...SO DID NOT INCLUDE IN THE 06Z TAF FOR KBFF. WILL SEE A CHANGE THOUGH MONDAY AFTERNOON AS WE SEE NORTHEASTERLY UPSLOPING WINDS EAST OF THE LARAMIE RANGE. CONTINUED THE TREND DOWN ON CEILINGS MONDAY AFTERNOON. WILL LIKELY SEE IFR/LIFR CONDITIONS MONDAY EVENING FOR MUCH OF THE PANHANDLE AND AIRPORTS EAST OF THE LARAMIE RANGE THROUGH TUESDAY. && .FIRE WEATHER... ISSUED AT 342 PM MDT SUN SEP 27 2015 FIRE WEATHER CONCERNS WILL BE MINIMAL THROUGH THIS WEEK. A COLD FRONT WILL BRING COOLER TEMPERATURES TO THE AREA TOMORROW AND TUESDAY ALONG WITH HIGHER MINIMUM RELATIVE HUMIDITIES. WINDS WILL ALSO GENERALLY BE ON THE LIGHTER SIDE BOTH MONDAY AND TUESDAY. WARMER MIDWEEK WITH BREEZY CONDITIONS. MINIMUM RELATIVE HUMIDITY VALUES MAY DROP TO AROUND 20 PERCENT THURSDAY AFTERNOON WEST OF THE LARAMIE RANGE WITH NEAR CRITICAL FIRE WEATHER CONDITIONS. BY FRIDAY AND SATURDAY IT IS LOOKING MORE LIKELY THAT A WEATHER DISTURBANCE WILL BRING WIDESPREAD PRECIPITATION TO THE AREA WITH SNOW INTO THE MOUNTAINS OF SOUTHEAST WYOMING. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...NONE. NE...NONE. && $$ SHORT TERM...SML/KC LONG TERM...REC AVIATION...GCC FIRE WEATHER...SML
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
928 AM EDT MON SEP 28 2015 .SYNOPSIS... HIGH PRESSURE EXTENDED FROM THE NORTHEASTERN STATES OUT OVER THE ATLANTIC EARLY THIS MORNING AND WEAK LOW PRESSURE WAS LOCATED OFF THE SOUTHEAST COAST. THE HIGH WILL CONTINUE TO MOVE FARTHER OUT TO SEA AND THE LOW SHOULD DRIFT NORTHWARD THROUGH TUESDAY NIGHT. A COLD FRONT IS FORECAST TO APPROACH FROM THE NORTHWEST AND IT SHOULD PASS THROUGH OUR REGION ON WEDNESDAY. THE BOUNDARY IS EXPECTED TO STALL OFF THE COAST FOR THURSDAY AND FRIDAY AS AREAS OF LOW PRESSURE MOVE NORTHWARD ALONG IT. ONE OF THE LOWS IS ANTICIPATED TO STRENGTHEN AS IT REACHES EASTERN CANADA OVER THE WEEKEND, PULLING THE FRONT FARTHER OUT TO SEA AND ALLOWING HIGH PRESSURE TO BEGIN BUILDING INTO OUR REGION. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... SURFACE HIGH PRESSURE RIDGE REMAINS ENTRENCHED ALONG THE APPALACHIANS. LOW LEVEL MOISTURE DUE TO THE CONTINUED ONSHORE FLOW AND A WEAKER PRESSURE GRADIENT HAS ALLOWED FOG TO DEVELOP THIS MORNING, ESPECIALLY CLOSER TO THE COAST. EXPECT THE FOG TO DISSIPATE BY LATE MORNING, WITH CONSIDERABLE CLOUDINESS FOR THE REMAINDER OF THE DAY. THERE IS GREATER MOISTURE IN THE COLUMN COMPARED TO YESTERDAY, BUT THERE IS NOT MUCH IN THE WAY OF LIFT, SO EXPECTING A DRY DAY. THE ONLY EXCEPTION WILL BE ALONG THE COAST WHERE THE NAM AND HRRR INDICATE SOME LIGHT RAIN SHOWERS MOVING ONSHORE. CURRENT RADAR AND SATELLITE TRENDS SUPPORT THIS, SO HAVE INSERTED A SLIGHT CHANCE OF RAIN SHOWERS INTO THE FORECAST ALONG THE COAST. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 AM TUESDAY/... THE DRY AIR CONTINUES TO BE REPLACED BY EVEN MORE MOIST AIR OVERNIGHT TONIGHT AS THE HIGH PULLS FARTHER AWAY FROM THE AREA. WITH ADDITIONAL VORTICITY IMPULSES WITHIN THE SOUTHWEST FLOW ALOFT, RAIN CHANCES CONTINUE TO INCREASE OVERNIGHT. ADDITIONALLY, THERE COULD BE SOME FOG DEVELOP ONCE AGAIN, ESPECIALLY FOR HIGHER ELEVATIONS ACROSS NORTHEAST PENNSYLVANIA AND NORTHWEST NEW JERSEY. WE`VE INCLUDED FOG ONCE AGAIN IN THE GRIDS ACROSS THOSE AREAS WHERE VISIBILITIES MAY BE LOWER. OVERNIGHT LOWS ARE EXPECTED TO BE SEVERAL DEGREES ABOVE NORMAL, AS CLOUDS SHOULD PREVENT ANY RADIATIONAL COOLING. && .LONG TERM /TUESDAY THROUGH SUNDAY/... THE HIGH OFF THE COAST WILL CONTINUE TO LOSE ITS INFLUENCE OVER OUR REGION ON TUESDAY. WARM HUMID AIR IS ANTICIPATED TO SETTLE INTO OUR REGION WITH MAXIMUM TEMPERATURES EXPECTED TO BE MAINLY IN THE UPPER 70S AND LOWER 80S. THE POTENTIAL FOR RAIN SHOWERS WILL BE ON THE INCREASE THROUGH THE DAY, ESPECIALLY IN OUR COUNTIES IN EASTERN PENNSYLVANIA AS A COLD FRONT BEGINS TO APPROACH FROM THE NORTHWEST. THE MODEL GUIDANCE HAS BEEN TRENDING TOWARD A LESS PROGRESSIVE SOLUTION WITH THE COLD FRONT. IT NOW APPEARS AS THOUGH IT WILL PASS THROUGH OUR FORECAST AREA ON WEDNESDAY BEFORE STALLING OFF THE COAST FOR THURSDAY AND FRIDAY. PRECIPITABLE WATER VALUES ARE FORECAST TO REACH AND EXCEED 2 INCHES IN MOST OF OUR FORECAST AREA AHEAD OF THE COLD FRONT. AS A RESULT, WE WILL CONTINUE TO MENTION THE POTENTIAL FOR HEAVY RAINFALL. ALSO, WE HAVE INCLUDED A CHANCE OF THUNDERSTORMS AS THE LIFT WITH AND AHEAD OF THE FRONT SEEMS FAIRLY ROBUST. GENERAL RAINFALL AMOUNTS OF AN INCH OR TWO SEEM POSSIBLE FOR MUCH OF OUR REGION. BEING THAT ANTECEDENT CONDITIONS HAVE BEEN QUITE DRY, OUR THINKING IS THAT WE WILL SEE SOME LOCALIZED FLOODING IN AREAS OF POOR DRAINAGE BUT THE POSSIBILITY OF WIDESPREAD FLOODING IS LOW. CLOUDS AND A CHANCE OF LIGHT RAIN SHOULD LINGER DURING THE LATE WEEK PERIOD WITH THE FRONT STALLED OFF THE COAST. THE TIMING AND STRENGTH OF LOW PRESSURE WAVES MOVING ALONG THE BOUNDARY REMAINS QUITE UNCERTAIN AT THIS TIME, SO THE DETAILS OF THE FORECAST REMAIN LOW CONFIDENCE AT THIS POINT. WE WILL GO WITH THE IDEA OF A STRENGTHENING LOW FINALLY BEGINNING TO PULL THE FRONT FARTHER OFF THE COAST OVER THE WEEKEND. IT MAY ALLOW HIGH PRESSURE AND SOME CLEARING TO BEGIN WORKING INTO OUR REGION FROM THE WEST AT THAT TIME. DAYTIME TEMPERATURES SHOULD FALL BELOW NORMAL FOR THE LATE WEEK PERIOD INTO THE WEEKEND IN THE WAKE OF THE COLD FRONT. && .AVIATION /13Z MONDAY THROUGH FRIDAY/... THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY AND SURROUNDING AREAS. CEILINGS HAVE LOWERED TO IFR AT DAYBREAK. FOG HAS ALSO DEVELOPED, WITH THE LOWEST CEILINGS NEAR THE COAST, WHERE ACY HAS BEEN DOWN TO 1/4SM ATTMS. THE FOG SHOULD DIMINISH AROUND 15Z. HOWEVER, THE LOW CLOUDS ARE EXPECTED TO REMAIN ACROSS THE SITES THROUGH MID MORNING, THEN BEGIN LIFTING TO MVFR, THEN VFR BY THE AFTERNOON. AFTER A PERIOD OF VFR FOR THE AFTERNOON INTO THE EARLY EVENING, CIGS ARE EXPECTED TO LOWER BACK TO MVFR DURING THE EVENING HOURS, AND EVENTUALLY BACK TO IFR/LIFR OVERNIGHT. IN ADDITION, FOG MAY BE MORE EXTENSIVE TONIGHT AND TUESDAY MORNING. NORTHEASTERLY WINDS EARLY IN THE DAY ARE EXPECTED TO BECOME MORE EASTERLY, THEN SOUTHEASTERLY LATER IN THE DAY AND CONTINUE INTO THE OVERNIGHT HOURS. WIND SPEEDS ARE EXPECTED TO BE 5-10 KNOTS THROUGH THE PERIOD. OUTLOOK... TUESDAY...IFR AND MVFR CONDITIONS IN THE MORNING GRADUALLY IMPROVING TO MAINLY VFR FOR THE AFTERNOON. A CHANCE OF SHOWERS. TUESDAY NIGHT AND WEDNESDAY...RAIN DEVELOPING AND BECOMING HEAVY AT TIMES ALONG WITH A CHANCE OF THUNDERSTORMS. MVFR AND IFR CONDITIONS ARE LIKELY. WEDNESDAY NIGHT...MAINLY VFR WITH A CHANCE OF RAIN. THURSDAY...MAINLY VFR. A CHANCE OF RAIN, MOSTLY TO THE SOUTH AND SOUTHEAST OF KPHL. THURSDAY NIGHT...MAINLY VFR. FRIDAY...MAINLY VFR WITH A CHANCE OF RAIN. && .MARINE... AS THE FLOW RELAXES ACROSS THE AREA, WINDS HAVE DROPPED BELOW 25 KNOTS. HOWEVER, SEAS REMAIN ELEVATED ACROSS THE WATERS. THEREFORE WE WILL KEEP THE SMALL CRAFT ADVISORY, BUT HAVE CONVERTED IT TO SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS. OUTLOOK... TUESDAY AND TUESDAY NIGHT...A SMALL CRAFT ADVISORY REMAINS IN EFFECT FOR OUR OCEAN WATERS WITH WAVE HEIGHTS EXPECTED TO RANGE FROM 4 TO 6 FEET. WEDNESDAY THROUGH FRIDAY...SMALL CRAFT ADVISORY CONDITIONS WILL LIKELY CONTINUE ON OUR OCEAN WATERS AND ON DELAWARE BAY DUE TO AN INCREASING NORTHEAST WIND. WAVE HEIGHTS ON OUR OCEAN WATERS ARE FORECAST TO BUILD TO 6 TO 12 FEET. GALE FORCE GUSTS ARE POSSIBLE ON OUR OCEAN WATERS FROM WEDNESDAY NIGHT INTO FRIDAY. && .TIDES/COASTAL FLOODING... TIDES WILL CONTINUE TO RUN HIGH TODAY INTO TONIGHT AND APPROACH THE MINOR FLOOD LEVEL. HOWEVER, WE DO NOT EXPECT THE LEVELS TO REACH CRITERIA REQUIRED TO ISSUE A FLOOD ADVISORY. A STRONG NORTHEASTERLY SURFACE FLOW IS FORECAST TO REDEVELOP DURING THE SECOND HALF OF THE WORK WEEK. AS A RESULT, WE MAY SEE ANOTHER ROUND OF MINOR TIDAL FLOODING AT THAT TIME. ALSO, BEACH EROSION IS POSSIBLE. && .RIP CURRENTS... THE COMBINATION OF HIGH WAVES, MODERATE PERIOD SWELL, AND A STEADY EASTERLY FLOW WILL CONTINUE TO CREATE A HIGH RISK FOR THE DEVELOPMENT OF DANGEROUS RIP CURRENTS THROUGH THIS EVENING. AFTER TODAY, THERE MAY BE A WEAK ENOUGH FLOW ON TUESDAY AND WEDNESDAY TO HAVE THE DANGEROUS RIP CURRENT RISK LESS THAN HIGH. THE SURF ZONE FORECAST ENDS WITH THE MORNING FORECAST ON WEDNESDAY THE 30TH. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...NONE. NJ...HIGH RIP CURRENT RISK UNTIL 8 PM EDT THIS EVENING FOR NJZ014- 024>026. DE...HIGH RIP CURRENT RISK UNTIL 8 PM EDT THIS EVENING FOR DEZ004. MD...NONE. MARINE...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 6 AM EDT WEDNESDAY FOR ANZ450>455. && $$ SYNOPSIS...IOVINO NEAR TERM...FRANCK SHORT TERM...ROBERTSON LONG TERM...IOVINO AVIATION...FRANCK/IOVINO/ROBERTSON MARINE...IOVINO/ROBERTSON TIDES/COASTAL FLOODING... RIP CURRENTS...
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
731 AM EDT MON SEP 28 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 419 AM EDT MON SEP 28 2015 00Z RAOBS/LATEST WV IMAGERY AND RAP ANALYSIS SHOW ZONAL FLOW ALONG THE CNDN BORDER AS RATHER SHEARED SHRTWV STRETCHING FM THE NRN PLAINS INTO NW ONTARIO HAS WEAKENED THE UPR RDG THAT HAS BEEN SO PERSISTENT RECENTLY OVER ERN NAMERICA. THIS SHRTWV IS SUPPORTING A SFC COLD FNT THAT IS MOVING E THRU WRN LK SUP EARLY THIS MRNG. SINCE THIS DISTURBANCE IS SHEARED OUT AND THE MSTR INFLOW IN THE SW FLOW AHEAD OF THE FNT IS RATHER MODEST...SHOWER COVERAGE AHEAD OF THE INCOMING FNT IS RATHER LIMITED...WITH SCT COVERAGE LIMITED BY THE HIER STABILITY/DRY MID LVLS SHOWN ON THE 00Z MPX RAOB. CLDS IN ADVANCE OF THE FNT ARE PUSHING THRU THE WRN CWA...BUT THERE IS AN AXIS OF MOCLR SKIES OVER THE CENTRAL TO W OF SOME LO CLDS ACRS THE SE HALF OF THE CWA ASSOCIATED WITH LLVL MSTR SHOWN ON THE 00Z GRB/APX RAOBS. STEADY SW WINDS IN THE WARM SECTOR ARE KEEPING TEMPS WELL ABOVE NORMAL NOT FAR FM 60 EVEN WHERE THE SKY IS MOCLR. LOOKING FARTHER TO THE W...THE 00Z ABERDEEN SDAKOTA ROAB SHOWS A VERY DRY AIRMASS IS UNDER SFC HI PRES RDG TRAILING THE SFC COLD FNT. BUT FARTHER TO THE W...THERE IS AN AREA OF COLDER CLD TOPS/SHOWERS/EVEN SOME LTG STRIKES MOVING THRU THE NRN PLAINS. MODELS SHOW AREA OF UPR DVGC/MID LVL FGEN IN RRQ OF 100KT H3 JET MAX SUPPORTING THE NW ONTARIO SHRTWV IS OVER THIS AREA OF COLDER CLD TOPS. ANOTHER SHRTWV IS DIGGING THRU SCENTRAL CANADA AND DEEPENING AN UPR TROF THERE. MAIN FCST CONCERNS IN THE SHORT TERM FOCUS ON POPS ASSOCIATED WITH COLD FNT THAT WL BE CROSSING UPR MI TODAY. TODAY...LATEST SHORT TERM GUIDANCE IS IN GOOD AGREEMENT SHOWING SFC COLD FNT CROSSING UPR MI TODAY AND REACHING LK MI ARND 21Z. SINCE UPR DVGC/AXIS OF MID LVL FGEN SUPPORTING AREA OF DISTURBED WX IN THE NRN PLAINS IS FCST TO MOVE OVER THE UPR LKS WHILE THE FNT IS CROSSING THE CWA...MOST OF THE MODELS SHOW SHOWER COVERAGE EXPANDING WITH TIME. SINCE THE DRY AIR SHOWN ON THE ABERDEEN RAOB AND TRAILING THE FNT IS MOST LIKELY TO IMPACT THE WRN CWA BEFORE THE ARRIVAL...WL FCST THE HIEST LIKELY POPS OVER THE SE HALF OF UPR MI THIS AFTN. ALTHOUGH THERE HAVE BEEN SOME LTG STRIKES OBSVD UPSTREAM...MODEL FCST MUCAPES NO HIER THAN ABOUT 100 J/KG OVER THE CWA SUPPORT LEAVING TS OUT OF THE FCST FOR NOW. WITH EARLIER COLD FROPA OVER THE W...TEMPS THERE WL BE MUCH LOWER THAN YDAY. TNGT...MODELS DIFFER ON HOW QUICKLY THE SHOWERS EXIT THE SE CWA THIS EVNG. THE 00Z NAM IS QUITE A BIT SLOWER THAN THE REST OF THE GUIDANCE...BUT FAVOR THE FASTER DRYING TREND SHOWN BY THE MAJORITY OF THE OTHER MODELS GIVEN DRYNESS OF THE TRAILING AIRMASS DEPICTED ON THE 00Z ABERDEEN RAOB. THESE MODELS FAVOR SOME LINGERING HIER LIKELY POPS EARLY IN THE EVNG OVER THE SE BEFORE VIGOROUS DRYING BRINGS A CLRG TREND EVEN THOUGH ANOTHER COLD FNT ASSOCIATED WITH SHRTWV NOW DIGGING THRU SCENTRAL CANADA IS PROGGED TO PASS OVERNGT. H85 TEMPS DROPPING TO ARND 0C OVER THE KEWEENAW BY 12Z TUE WL RESULT IN A MUCH COOLER OVERNGT WITH MIN TEMPS DIPPING TO ARND 40 AND PERHAPS THE UPR 30S AT SOME OF THE HIER TERRAIN LOCATIONS. STRONG NW FLOW OVER THE RELATIVELY WARM LK WATERS WL LIMIT THE TEMP DROP. ALTHOUGH THE SFC-H85 DELTA T BTWN THE RELATIVELY WARM LK WATERS /MID TO UPR 50S F/IS SUFFICIENT FOR LK CLDS/PCPN...THE INCOMING AIRMASS WL BE TOO DRY AND THE LLVL FLOW TOO ACYC TO SUPPORT MORE THAN SCT CLDS OVER THE HIER TERRAIN. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 409 AM EDT MON SEP 28 2015 UPPER LEVEL TROUGH FROM HUDSON BAY TO UPPER GREAT LAKES SLIDES TO EASTERN CANADA LATE THIS WEEK WHILE HEIGHTS SLOWLY REBOUND FM NORTHERN PLAINS TO UPPER GREAT LAKES. TROUGH WILL ENSURE A COOLER WEEK WITH FROST/FREEZE OVER PARTS OF CWA TUE NIGHT AND MAYBE WED NIGHT AS WELL. ON TUESDAY...COOLER AIR ARRIVES WITH H85 TEMPS DOWN TO 0C TO -1C BY AFTN. NORTHWEST WINDS COULD BE GUSTY UP TO 25 MPH...ESPECIALLY CLOSER TO LK SUPERIOR. THOUGH APPROACHING HIGH IS THE DOMINANT FACTOR...NAM/GFS/GEM-REGIONAL INDICATE HIGHER H85 RH MOVING ACROSS LK SUPERIOR BY 12Z AND EXPANDING BY 18Z AS THE COOLER AIR ARRIVES. ENVISION FEW-SCT STRATOCU CLOUDS EXPANDING INTO A STRATOCU/CUMULUS DECK MAINLY CNTRL CWA BY AFTN...THEN DIMINISHING THROUGH THE REST OF AFTN. WITH THE CLOUDS AND COLD AIR ADVECTION...TEMPS WILL ONLY REACH LOW TO MID 50S NEAR LK SUPERIOR AND MAY TOUCH 60 DEGREES IN THE FAR SCNTRL. EVEN THOUGH SWIM RISK WILL BE HIGH ALONG MARQUETTE AND ALGER COUNTIES...AIR TEMPERATURES BELOW 55 DEGREES WILL PROHIBIT THE ISSUANCE OF A BEACH HAZARDS STATEMENT. NEXT UP IS TUE NIGHT AND THE FROST/FREEZE POTENTIAL. UPSHOT IS THE FROST/FREEZE POTENTIAL...AT LEAST AWAY FM THE INTERIOR WEST...IS NOT AS CLEAR CUT AS IT LOOKED THE LAST FEW DAYS. RECENTLY IN THE MODELS...IT APPEARED THAT THE APPROACHING HIGH WOULD SETTLE RIGHT OVERHEAD TUESDAY NIGHT. NOW...RIDGE AXIS STAYS MAINLY OVER WESTERN UPR MICHIGAN WHILE A LIGHT BUT PERSISTENT NE LOW-LEVEL FLOW AFFECTS EAST HALF OF CWA /SEE THIS AS 950-900MB WINDS OVER 10 KTS FM NCNTRL INTO EASTERN CWA. ALSO...WITH H85 TEMPS STAYING AROUND -1C OVERNIGHT TUESDAY NIGHT AND MORE OF AN ONSHORE WIND WITH SOME 875MB-850MB MOISTURE SHOWN ON GFS/NAM SOUNDINGS...MAY HAVE TO CONTEND WITH SCT- BKN LAKE EFFECT CLOUDS AS DELTA T VALUES WILL BE OVER 15C. BEST CHANCE FOR BKN CLOUDS WOULD BE OVER FAR NCNTRL UPR MICHIGAN AND ACROSS THE KEWEENAW. ADJUSTED SKY GRIDS TO BUMP UP CLOUD COVER FOR THERE AREAS...ESPECIALLY FOR THE KEWEENAW. FOR TEMPS...USED GUIDANCE THAT SHOWED LOWEST TEMPS IN THE UPR 20S OVER INTERIOR WEST BUT KEPT READINGS MAINLY MID-UPR 30S WHERE CLOUDS MAY DISRUPT COOLING. AFTER A MOSTLY SUNNY BUT COOL DAY ON WED...ANOTHER CHILLY NIGHT WITH SOME FROST SEEMS PROBABLE FOR WED NIGHT. SETUP IS NO BETTER THAN TUE NIGHT THOUGH AS HIGH CENTER IS MORE OVER QUEBEC AND THAT LEAVES A LIGHT EASTERLY FLOW ACROSS UPR MICHIGAN. EVEN SO...MIN TEMPS MAY BE AT LEAST IN LOWER 30S...ESPECIALLY OVER INLAND AREAS. DAYTIME HIGHS WED INTO THU SHOULD STAY IN THE 50S TO AROUND 60 DEGREES. THESE VALUES ARE PRETTY SEASONABLE FOR LATE SEPTEMBER...THOUGH MUCH COOLER THAN THE WELL ABOVE NORMAL TEMPS SEEN MUCH OF THIS MONTH. AFTER SOME RAIN TODAY...DRIER TREND THAT BEGAN TO SHOW UP IN THE MODELS LAST COUPLE DAYS CONTINUES AS HIGH PRESSURE BUILDING IN BEHIND COLD FRONTAL PASSAGE TODAY EXPANDS ACROSS THE UPPER GREAT LAKES ON WED AND BUILDS FURTHER TO OVER 1040MB IN QUEBEC ON FRIDAY. RIDGE FM THE HIGH EXPANDS WESTWARD ACROSS THE UPPER GREAT LAKES AND AS FAR WEST AS SASKATCHEWAN AND MANITOBA. AT FIRST GLANCE...THIS SHOULD KEEP MAJORITY OF REGION DRY THROUGH THE UPCOMING WEEKEND. HOWEVER...GFS AND 12Z ECMWF INDICATE THAT DECENT STRENGTH SHORTWAVE TROUGH BREAKING FREE FM THE LARGER SCALE TROUGH OVER EASTERN CANADA WILL SLIDE OVER UPR GREAT LAKES FRIDAY INTO THE WEEKEND. 00Z ECMWF NOT NEAR AS DEEP WITH TROUGH AS IT SHOWED WITH 12Z RUN THOUGH. DEEP MOISTURE APPEARS SPOTTY BUT THERE ARE HINTS THERE MAY BE ENOUGH FORCING AND MOISTURE TO SUPPORT SOME SHOWERS. OVERALL MOST CWA WILL REMAIN DRY THROUGH NEXT WEEKEND AS UPPER LEVEL TROUGH WILL BE LACKING LOW-LEVEL SUPPORT AS THE SFC HIGH REMAINS THE DOMINANT WEATHER FEATURE. IF THERE ENDS UP BEING BETTER CYCLONIC FLOW IN LOW- LEVELS AS 12Z ECMWF INDICATED...COULD SEE HELP FM LK SUPERIOR FOR PRECIP AS H85 TEMPS ARE FORECAST TO BE AS LOW AS -3C WITH THE UPPER TROUGH OVERHEAD. DAYTIME HIGHS SHOULD SETTLE BACK INTO THE 50S FRIDAY AND SATURDAY WITH THE COOLER TEMPS ALOFT. FINALLY...GFS IS MUCH MORE AGGRESSIVE THAN ECMWF WITH SECONDARY STRONGER SHORTWAVE TROUGH MOVING THROUGH IN MORE TYPICAL NW TO SE PROGRESSION LATE NEXT WEEKEND INTO EARLY NEXT WEEK /DAYS 8-10/. H85 TEMPS AS LOW AS -9C IN THE CORE OF THE COLDEST AIR OVER ONTARIO WITH AROUND -5C OVER UPR MICHIGAN LAST TWO RUNS. NEITHER THE 12Z RUN OR MOST RECENT 00Z RUN OF ECMWF SHOWED ADDITIONAL TROUGHING THOUGH WITH RIDGING RE APPEARING INTO NEXT WEEK IN WAKE OF THE WEEKEND TROUGHING. ECMWF DOES INDICATE TROUGHING AND SIMILAR DEGREE OF COLD AIR...BUT IT STAYS WELL UPSTREAM OVER NORTHWEST CANADA MOST OF THE WEEK. FOR THE FORECAST...CONSENSUS SHOULD COVER IT ATTM. USUALLY DO NOT GET TOO CONCERNED WITH THESE TYPE OF DETAILS IN THE FAR REACHES OF EXTENDED AND BEYOND...BUT GIVEN THE VERY WARM SEPTEMBER ABOUT TO CONCLUDE /POTENTIALLY RECORD WARMEST AT SOME LOCATIONS ACROSS UPR MICHIGAN/...IT IS NOTABLE THAT SOME MODELS ARE HINTING AT COOLER AIRMASSES CLOSE BY AS FIRST FULL WEEK OF OCTOBER ARRIVES. OFFICIAL 8-14 DAY AND EXPERIMENTAL 3-4 WEEK FORECASTS FM CPC STILL INDICATING WARMER THAN NORMAL TEMPERATURES SHOULD PREVAIL OVERALL THROUGH MUCH OF NEXT MONTH. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING) ISSUED AT 731 AM EDT MON SEP 28 2015 A COLD FNT THAT IS APRCHG CMX AND IWD WL PRESS SEWD AND BY SAW BY NOON. SOME -SHRA ASSOCIATED WITH A WAVE OF LO PRES RUNNING ALONG THIS BNDRY WL IMPACT SAW AND PERHAPS IWD...WITH SOME MVFR CONDITIONS PSBL AT THOSE SITES WHEN THE -SHRA ARE MOST LIKELY AT THOSE PLACES FM LATE THIS MRNG INTO THE AFTN. CMX IS MOST LIKELY TO MISS THIS PCPN AND REMAIN VFR. THE ARRIVAL OF DRIER AIR IN THE AFTN WL BRING A RETURN TO VFR CONDITIONS AT IWD AND THEN SAW. ALTHOUGH ANOTHER COLD FNT WL SWING THRU TNGT WITH A STRONGER NNW WIND IN ITS WAKE...THE AIRMASS WL BE TOO DRY FOR MORE THAN A FEW CLDS. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 419 AM EDT MON SEP 28 2015 SW WINDS UP TO 25 KTS THIS MRNG AHEAD OF A COLD FRONT MOVING THRU WESTERN LAKE SUPERIOR EARLY THIS MORNING WILL SHIFT TO THE W-NW UP TO 20 KTS FOLLOWING THE FRONTAL PASSAGE BY EARLY AFTERNOON OVER THE FAR EAST. ANOTHER COLD FRONT WILL SWING ACROSS THE LAKE TONIGHT. EXPECT NNW WINDS TO INCREASE UP TO 25-30 KTS IN ITS WAKE LATE TONIGHT/TUE. AS A TRAILING HIGH PRESSURE CLOSES IN ON THE AREA ON TUE NIGHT/WED...WINDS WILL DIMINISH TO UNDER 15-20 KTS. ONCE THE HIGH SHIFTS INTO QUEBEC LATER IN THE WEEK...E WINDS UP TO 20 KTS WILL DOMINATE. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...KC LONG TERM...JLA AVIATION...KC MARINE...KC
AREA FORECAST DISCUSSION
NWS DULUTH MN
634 AM CDT MON SEP 28 2015 .SHORT TERM...(TODAY THROUGH TUESDAY) ISSUED AT 304 AM CDT MON SEP 28 2015 A WEAK COLD FRONT IS SLOWLY SLIDING SOUTHEAST ACROSS THE FORECAST AREA EARLY THIS MORNING...GENERALLY DRAPED FROM LAKE SUPERIOR SOUTHEAST ACROSS CENTRAL MINNESOTA AND ON INTO SOUTH DAKOTA. SOME SCATTERED SHOWERS ARE AFFECTING NORTHWEST WISCONSIN OUT AHEAD OF IT...BUT NOT BRINGING MUCH IN THE WAY OF PRECIPITATION. SOME FOG HAS FORMED BEHIND THE FRONT...BUT VISIBILITIES ARE STILL IN THE 3-5 MILE RANGE AND DO NOT EXPECT CONDITIONS TO GET MUCH WORSE. THE FRONT WILL CONTINUE TO SLIDE SOUTHEAST THIS MORNING...AND SHOULD BE SOUTHEAST OF THE FORECAST AREA BY MID DAY. OF INTEREST ON SATELLITE IMAGERY THIS MORNING IS A SHORTWAVE MOVING OUT OF WYOMING AND INTO SOUTH DAKOTA...WITH SOME DECENTLY COLD CLOUD TOPS AND A FAIR AMOUNT OF LIGHTNING WITH IT...SOMEWHAT UNUSUAL FOR THIS TIME OF YEAR AND DAY. THUS...EXPECT THAT THIS PARTICULAR FEATURES IS PROBABLY STRONGER THAN MOST OF THE MODELS SHOW...AND EXPECT IT TO CONTINUE TO RIPPLE EAST ALONG THE COLD FRONT DURING THE DAY TODAY. BASED ON THIS STRONGER FEATURE HAVE GONE WITH HIGHER POPS ACROSS MY SOUTHEASTERN CWA DURING THE DAY TODAY...USING THE 06Z HRRR RUN FOR THE GENERAL PLAN AND HAVE MADE SOME OTHER TWEAKS TO PLACE A BAND OF SHOWERS AND ISOLATED THUNDERSTORMS ACROSS MY NW WISCONSIN COUNTIES DURING THE DAYTIME TODAY...GENERALLY FROM 15Z TO 21Z. OTHERWISE...IT SHOULD BE A FAIRLY DECENT DAY WITH HIGHS IN THE 60S MOST LOCATIONS AND LIGHT WINDS. TONIGHT THE FRONT DROPS FAR ENOUGH SOUTH THAT THE RIDGE OF HIGH PRESSURE CAN BUILD INTO THE AREA FOR TONIGHT AND TUESDAY. THIS SHOULD SET US UP FOR A GOOD RADIATIONAL COOLING NIGHT WITH CLEAR OR NEARLY CLEAR SKIES AND COLD TEMPERATURES ALOFT TO ACCOMPANY THE COLD AIRMASS MOVING INTO THE AREA. LATEST GUIDANCE INDICATES THAT WE WILL HAVE SOME 850MB TEMPS IN THE -3 C RANGE BY 12Z. THIS SHOULD SET US UP FOR SOME CHILLY TEMPERATURES TONIGHT...WITH LOWS DIPPING INTO EVEN THE UPPER 20S IN SOME OF OUR COLD SPOTS AND 30S ELSEWHERE. FROST IS A REAL POSSIBILITY. HAVE LEFT IT TO THE DAY SHIFT TO SEND OUT A FROST/FREEZE ADVISORY AS SPECIFIC LOCATIONS ARE STILL SOMEWHAT IN QUESTION...BUT ANTICIPATE THAT WE WILL NEED ONE OR BOTH FOR AT LEAST PARTS OF THE FORECAST AREA. TUESDAY TO REMAIN CHILLY WITH HIGHS ONLY IN THE 50S IN THIS CHILLY AIRMASS...AND THE DRY AIR TO BRING OUR MIN RH VALUES DOWN INTO THE 20 PERCENT RANGE DURING THE AFTERNOON. .LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY) ISSUED AT 304 AM CDT MON SEP 28 2015 LOW CONFIDENCE IN THE PATTERN LATE WEEK INTO THE WEEKEND DUE TO A WIDE RANGE IN MODEL SOLUTIONS...BUT SOME NOTABLE TRENDS ARE BEGINNING TO EMERGE. A COOL TUESDAY NIGHT WITH TEMPERATURES FALLING TO NEAR FREEZING IN SOME LOCATIONS...THEN GENERALLY SEASONABLE TEMPERATURES WITH LOW CHANCES FOR PRECIPITATION THROUGH THE REST OF THE PERIOD. ON THE SYNOPTIC SCALE THE LONG TERM PERIOD BEGINS WITH AN AMPLIFIED RIDGE ACROSS THE INTERMOUNTAIN WEST AND BROAD TROUGH OVER THE SOUTHEAST. AN AREA OF HIGH PRESSURE WILL BE DRIFTING EASTWARD WITH WEST/SOUTHWEST FLOW AT LOW/MID LEVELS DEVELOPING ON WEDNESDAY. AS THIS HIGH DEPARTS TUESDAY NIGHT TEMPS ARE EXPECTED TO FALL TO NEAR FREEZING...MAINLY ACROSS INLAND NORTHWEST WISCONSIN BUT ALSO IN POCKETS ACROSS THE IRON RANGE AND MN ARROWHEAD. AN EMBEDDED SHORTWAVE TROUGH JUST AHEAD OF THE RIDGE AXIS WILL DIVE SOUTHWARD FROM SASKATCHEWAN/MANITOBA INTO THE NORTHERN PLAINS. WHILE THE BEST UPPER LEVEL FORCING WILL BE IN SOUTHERN MANITOBA...WITH WARM AIR ADVECTION AND A FAIRLY DEEP LAYER OF MOISTURE IN PLACE THERE IS A CHANCE FOR SHOWERS LATE WED/WED NIGHT ACROSS NORTHWEST TO EVEN NORTH CENTRAL MINNESOTA...WITH THE BEST CHANCE TOWARDS THE BORDERLAND. WHILE CLOUDS WILL BE PRESENT ACROSS MUCH OF NORTHERN MINNESOTA WEDNESDAY...THEY SHOULD BEGIN TO CLEAR OUT THURSDAY AS EASTERLY LOW LEVEL WINDS PREVAIL DUE TO AN 850/700 MB HIGH OVER ONTARIO. FOR THE WEEKEND GUIDANCE IS ALL OVER THE PLACE WITH THE SYNOPTIC PATTERN...EVEN DISREGARDING THE CANADIAN MODEL WHICH HAS RECENTLY SHOWN POOR RUN TO RUN CONTINUITY. ONE INTERESTING FEATURE ON THE 00Z GFS IS A LOW THAT DROPS OUT OF EASTERN CANADA AND MOVES WESTWARD TOWARDS THE UPPER GREAT LAKES FRIDAY INTO SATURDAY. WHILE THE LATEST ECMWF DOES NOT SHOW THIS AS STRONGLY...PREVIOUS RUNS HAVE DEPICTED SUCH A FEATURE. ONE CONSISTENT FEATURE IS A 850MB HIGH OVER FAR NORTHWEST ONTARIO WHICH COULD BRING AS COLD AS 0C AIR OVER THE UPPER GREAT LAKES THIS WEEKEND. EASTERLY FLOW THIS COLD OVER A RELATIVELY WARM LAKE COULD PRODUCE SOME LAKE EFFECT /RAIN/ SHOWERS...BUT WITH QUESTIONS ABOUT THE UPPER PATTERN THROUGH THIS PERIOD CONFIDENCE REMAINS LOW. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING) ISSUED AT 633 AM CDT MON SEP 28 2015 EARLY THIS MORNING AREAS OF FOG ARE RESULTING IN IFR OR WORSE CONDITIONS AT INL AND HIB...BUT THESE WILL IMPROVE RAPIDLY TOWARDS SUNRISE. MID TO HIGH LEVEL VFR CLOUDS TODAY WITH NORTHWEST WINDS TODAY GUSTING TO NEAR 20KTS AT TIMES IN NORTHEAST MINNESOTA. IN NORTHWEST WISCONSIN A WEAK COLD FRONT WILL STALL OUT AND WITH AN UPPER LEVEL DISTURBANCE MOVING IN FROM THE WEST SCATTERED SHOWERS AND POSSIBLY A THUNDERSTORMS ARE EXPECTED. JUST WENT WITH VCSH AT HYR FOR NOW BASED ON CURRENT RADAR AS THE BEST CHANCES FOR THUNDER APPEAR FARTHER SOUTH. SKIES CLEAR OUT TONIGHT EVERYWHERE. && .PRELIMINARY POINT TEMPS/POPS... DLH 65 40 55 37 / 10 0 0 0 INL 61 30 55 33 / 0 0 0 0 BRD 67 39 59 38 / 20 0 0 0 HYR 67 37 58 29 / 60 0 0 0 ASX 68 40 57 34 / 30 0 0 0 && .DLH WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. LS...NONE. && $$ SHORT TERM...LE LONG TERM...JJM AVIATION...JJM
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON MS
1016 AM CDT MON SEP 28 2015 .UPDATE... GRIDS ADJUSTED THIS MORNING TO BUMP UP TEMPS...LOWER POPS AND ALLOW FOR A BIT MORE SUNSHINE. && .SHORT TERM... WATER VAPOR IMAGERY THIS MORNING SHOWS A WELL DEFINED UPPER LOW OVER SE TX SUPPORTING A BROAD S/SW FLOW IN THE MID/UPPER LEVELS ACROSS THE GULF COAST REGION. THREE SIGNIFICANT AREAS OF CONVECTION ARE OCCURRING IN THIS AREA: 1) CLOSE TO THE UPPER LOW OVER SE TX/SW LA AND ADJACENT WATERS...2) OVER THE WESTERN FL PANHANDLE IN COUPLED UPPER JET REGION BETWEEN JET MAXIMA OVER LOWER OHIO VALLEY AND WESTERN GULF OF MEXICO...3) IN A BROAD AREA OVER THE EASTERN GULF OF MEXICO ASSOCIATED WITH INVEST 99L. UNFORTUNATELY...FOR THOSE IN THE ARKLAMISS WANTING/NEEDING RAIN...IT APPEARS AS THOUGH THESE AREAS WILL REMAIN THE FOCUS FOR CONVECTIVE DEVELOPMENT TODAY. WATER VAPOR SHOWS ANOTHER DISTURBANCE AND AREA OF ASCENT OVER THE CENTRAL GULF LIFTING NE...BUT EXTRAPOLATION AND THE HRRR KEEPS THE FOCUS FOR NEW DEVELOPMENT ASSOCIATED WITH THIS SYSTEM TO OUR EAST. MORNING KJAN RAOB SHOWS THAT SIGNIFICANT DRYING HAS OCCURRED THROUGHOUT THE COLUMN WITH PW DOWN TO ABOUT 1.6 IN...AND WATER VAPOR IMPLIES THIS DRY AIR PARTICULARY IN MID AND UPPER LEVELS HAS OVERSPREAD MOST OF THE FORECAST AREA. VISIBLE IMAGERY SHOWS WIDESPREAD LOW CLOUDS ACROSS THE AREA...BUT WITH SOME BREAKS. GIVEN DRIER AIR ALOFT AND DECENT LOW/MID LEVEL FLOW EXPECT THAT SOME MIXING WILL CONTINUE TO ERODE BREAKS IN LOW CLOUDS AND ALLOW FOR SOME SUN AT TIMES AND A BIT OF LIMITED DAYTIME HEATING. GIVEN THIS HAVE ADJUSTED CLOUD COVER GRIDS DOWN A BIT FOR TODAY AND RAISED TEMPS A FEW DEGREES. COMBO OF SOME HEATING AND DRIER AIR IN MID/UPPER LEVELS SHOULD YIELD ENOUGH CONVECTIVE INSTABILITY FOR SCT SHRA/ISOLD TSRA THIS AFTERNOON. HOWEVER TRENDS AND RECENT HRRR RUNS IMPLY COVERAGE SHOULD NOT BE OVERLY IMPRESSIVE...AND HAVE HENCE LOWERED POPS EVEN A BIT MORE THAN EARLIER FORECAST. /AEG/ && .AVIATION... EXPECT THE MVFR/IFR CONDITIONS TO CONTINUE ACROSS TAF SITES THROUGH THE PERIOD AS A LARGE AREA OF LOW PRESSURE CENTERED OVER THE NORTHWEST GULF CONTINUES TO ROTATE MOISTURE OVER THE AREA. OCCASIONAL SHOWERS ARE POSSIBLE ACROSS THE AREA ALSO...BUT CONFIDENCE IN THE TIMING OF THESE SHOWERS IS LOW. THE WINDS WILL REMAIN OUT OF THE NORTHEAST TO EAST AT 5-8KTS THROUGH THE PERIOD./15/ && .PREV DISCUSSION... /ISSUED 454 AM CDT MON SEP 28 2015/ DISCUSSION... TODAY THROUGH TUESDAY NIGHT... MODEL CONSENSUS IS THAT THE MID/UPPER LEVEL LOW WILL MEANDER NORTHEASTWARD FROM SOUTHEAST TEXAS INTO LOUISIANA BEFORE OPENING UP AND SHEARING OUT AS IT EVENTUALLY GETS ABSORBED BY A FRONTAL BOUNDARY IN THE WESTERLIES. FOR NOW HOWEVER...DEEP CYCLONIC FLOW CONTINUES TO FUNNEL IN AN IMPRESSIVE PLUME OF TROPICAL MOISTURE FROM THE WESTERN CARIBBEAN REGION NORTHWARD TOWARD THE CENTRAL GULF COAST REGION (PRECIPITABLE WATER APPROACHING 2.5 INCHES). PER NHC GUIDANCE...IT APPEARS ANY HYBRID TROPICAL SYSTEM DEVELOPMENT ASSOCIATED WITH THE MOISTURE CHANNEL WILL BE FAR ENOUGH EAST TO NOT POSE CONCERNS FOR THE ARKLAMISS. THE HRRR DID A GOOD JOB YESTERDAY MORNING IN SIGNALING OR THE INLAND DEVELOPMENT OF HEAVIER CONVECTION ALONG THE I-59 CORRIDOR (KMEI OBSERVED > 2.5 INCHES OF RAINFALL) AND HAVE FOLLOWED IT AGAIN FOR TODAY. RECENT RUNS SUGGEST THAT THE CURRENT MESOSCALE VORTEX OVER WESTERN AL WILL CONTINUE TO SUPPORT WIDESPREAD RAINFALL THAT COULD IMPACT EASTERN MS OVER THE NEXT FEW HOURS...BUT ADDITIONAL RAINFALL AND SHOWER/TSTM DEVELOPMENT IS EXPECTED TO BE SCATTERED AND HAVE CUT BACK ON GUIDANCE POPS JUST A BIT. WEAK MID LAPSE RATES AND LIMITED DAYTIME HEATING DUE TO EXTENSIVE CLOUD COVER WILL LIMIT OVERALL TSTM POTENTIAL. AS THE SYSTEM BEGINS TO SHEAR OUT TUESDAY...RAIN CHANCES SHOULD DROP OFF SIGNIFICANTLY WITH DRIER AIR MOVING INTO THE REGION. OTHERWISE...EXPECT DAYTIME TEMPERATURES WILL CONTINUE TO BE ON THE MILD SIDE IN THIS WETTER/CLOUDIER REGIME. /EC/ WEDNESDAY THROUGH NEXT SUNDAY... THERE IS SOME UNCERTAINTY WITH REGARD TO THE SPECIFICS OF HYBRID GULF LOW DEVELOPMENT IN THE GULF OF MEXICO (OR VICINITY) IN THE COMING SEVERAL DAYS. HOWEVER...MODEL CONSENSUS IS QUITE GOOD THAT DEVELOPMENT EITHER IN THE EASTERN GULF OF MEXICO OR JUST OFF THE SOUTHEAST COAST WILL STRENGTHEN A BUILDING UPPER TROUGH DEEP DOWN INTO THE EASTERN CONUS THURSDAY AND FRIDAY. SUCH A PATTERN SHOULD HELP DRIVE A COLD FRONT THROUGH THE REGION WEDNESDAY AND PUSH ALL BUT MINUSCULE PRECIP CHANCES EAST OF OUR REGION BY THURSDAY. DESPITE THE LACK OF A TRULY CHILLY AIR MASS UP NORTH TO LATCH ONTO...THE PATTERN DEFINITELY HAS A COOL LOOK AND SHOULD BRING MOST OF THE REGION BELOW NORMAL READINGS FOR AT LEAST A FEW DAYS IN THE LONG TERM PERIOD. ONE CONCERN WHICH WILL BARE WATCHING IN THE COMING DAYS IS THE POTENTIAL FOR AN ENHANCED FIRE WEATHER RISK THURSDAY AND FRIDAY OWING TO INCREASED WINDS...RATHER LOW AFTERNOON HUMIDITY...AND THE CONTINUED DRY STRETCH OF WEATHER IN MANY LOCATIONS. OF COURSE...IF WE ARE FORTUNATE...THERE WILL BE WIDESPREAD SIGNIFICANT RAINS AROUND THE AREA OVER NEXT FEW DAYS TO ALLEVIATE MUCH OF THIS CONCERN FOR THURSDAY AND FRIDAY. DUE TO THIS FACET OF UNCERTAINTY THE HWO WILL BE LEFT CLEAR IN THIS REGARD FOR THE TIME BEING. BY NEXT WEEKEND THE NORTH AMERICAN CIRCULATION PATTERN SEEMS TO HOLD MORE THAN AN AVERAGE AMOUNT OF CHAOS THAT REMAINS TO BE WORKED OUT WITH SUFFICIENT CONFIDENCE BY NWP MODELS. REGARDLESS...POTENTIAL OF A WARMING TREND AND SLOWLY INCREASING RAIN CHANCES IS STILL DECENT OVER THIS STRETCH. /BB/ AVIATION...OVERALL...FLYING CONDITIONS WILL BE RATHER POOR AS WIDESPREAD MVFR/IFR CATEGORY STRATUS WILL PREVAIL FOR MUCH OF THE FORECAST PERIOD. A VERY MOIST AIRMASS ASSOCIATED WITH A LARGE AREA OF LOW PRESSURE WILL PRODUCE SCATTERED SHRA WHICH COULD IMPACT ALL TAF SITES AT SOME POINT...BUT CONFIDENCE ON EXACT TIMING IS UNUSUALLY LOW. /EC/ && .PRELIMINARY POINT TEMPS/POPS... JACKSON 79 69 83 69 / 44 41 51 29 MERIDIAN 78 68 83 67 / 63 66 51 37 VICKSBURG 84 67 84 67 / 42 40 49 27 HATTIESBURG 82 70 85 69 / 61 43 40 21 NATCHEZ 83 69 83 67 / 43 40 44 23 GREENVILLE 83 68 82 68 / 37 42 44 28 GREENWOOD 82 68 81 67 / 41 59 53 33 && .JAN WATCHES/WARNINGS/ADVISORIES... MS...NONE. LA...NONE. AR...NONE. && $$ AEG/15
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1135 AM EDT MON SEP 28 2015 .SYNOPSIS... SHOWERS WILL BE POSSIBLE TODAY, MAINLY OVER THE FINGER LAKES AND CENTRAL NEW YORK. SHOWERS WILL BECOME MORE LIKELY ON TUESDAY INTO WEDNESDAY, AS A COLD FRONT PUSHES INTO THE REGION. && .NEAR TERM /THROUGH TONIGHT/... 1130 AM UPDATE... THE CURRENT FORECAST FOR THIS AFTERNOON INTO THE EVENING STILL LOOKS REASONABLE, WITH JUST MINOR TWEAKS REQUIRED AT THIS TIME. SCATTERED SHOWERS WILL CONTINUE TO BE SEEN OVER OUR WESTERN AND NORTHERN ZONES, AS THE BEST MOISTURE FEED IS IN THIS AREA, AROUND THE OUTER PERIPHERY OF THE SLOWLY DEPARTING LOW-LEVEL RIDGE. LITTLE OR NO PRECIPITATION IS ANTICIPATED OVER THE NEAR-TERM, ALONG AND EAST OF THE I-81 CORRIDOR. DESPITE ABUNDANT CLOUD COVER, A MILD AIR MASS, ALONG WITH FURTHER LOW-LEVEL WARM ADVECTION, WILL STILL BRING HIGHS INTO THE 70S OVER MANY AREAS THIS AFTERNOON. PREVIOUS DISCUSSION... 400 AM UPDATE... AFTER GETTING LUCKY FOR MOST OF THE AREA LAST NIGHT BEING CLEAR ENOUGH TO VIEW THE ECLIPSE, REALITY IS SETTING IN WITH THICK CLOUDS ON OUR DOORSTEPS WITH SOME SHOWERS NOT FAR BEHIND. FOLLOWED LATEST HRRR QPF FIELDS AND INCREASED TO LIKELY POPS THROUGH MID MORNING FROM THE WESTERN SOUTHERN TIER UP THROUGH FINGER LAKES. PRECIP SHOULD MAKE IT TO CNY BUT MAY BREAK UP A BIT BY THE TIME THAT HAPPENS. LATER TODAY AND THROUGH TONIGHT RAIN CHANCES DON`T LOOK ALL THAT GREAT BUT WE CAN`T RULE ANYTHING OUT, ESPECIALLY IN PRETTY MUCH THE SAME AREAS JUST MENTIONED ABOVE. FARTHER SOUTH ESPECIALLY INTO PA, MAINLY DRY WEATHER IS EXPECTED. && .SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... 4 AM UPDATE... ALTHOUGH MY GARDEN IS WINDING DOWN DUE TO THE LOSS OF DAYLIGHT/LOW SUN ANGLE, I AM GETTING EXCITED ABOUT THE POSSIBILITY OF SOME RAIN AROUND HERE! RAIN CHANCES GO UP FOR OUR AREA BY TUESDAY AFTERNOON AS A COLD FRONT APPROACHES. CONTINUE TO MENTION SOME ISOLATED THUNDER THROUGH EARLY TUESDAY NIGHT TO MATCH WELL WITH OTHER OFFICES ALONG WITH THE FACT LI`S ARE NEAR OR BELOW ZERO. UNLIKE PAST RAIN EVENTS WITH EACH MODEL RUN WE ARE LOOKING AT INCREASING CHANCES FOR HIGHER RAINFALL AMOUNTS INSTEAD OF LOWER ONES. IN FACT THE MAIN TREND OF THE 0Z RUNS OF BOTH THE EURO AND GFS NOT ONLY RAISE RAINFALL AMOUNTS, THE PROGRESSION OF THE COLD FRONT THROUGH OUR AREA IS MUCH SLOWER. ACCORDINGLY I RAISED POPS ABOVE 70% FOR THE ENTIRE AREA TUESDAY NIGHT. IN FACT THROUGH MUCH OF WEDNESDAY NOW, WE HAVE POPS ABOVE 60% FROM NEAR BINGHAMTON SOUTH AND EAST. DRIER WEATHER NOW HOLDS OFF UNTIL WED NIGHT. AT EARLY LOOK AT TOTAL RAINFALL AMOUNTS WOULD BE A HALF OF AN INCH UP ACROSS THE FINGER LAKES, BUT EXCEEDING AN INCH FROM NEAR BINGHAMTON SOUTH AND EAST, WHERE PRECIP LINGERS THE LONGEST. && .LONG TERM /THURSDAY THROUGH SUNDAY/... 200 PM SUNDAY UPDATE... THOUGH DIFFERING ON DETAILS...MODELS ARE STARTING TO GET INTO BETTER LARGE SCALE AGREEMENT...ON THE IDEA OF AN UNSETTLED TROUGHY PATTERN TAKING SHAPE BY NEXT WEEKEND. ONSHORE FLOW...CUTOFF LOW EVOLUTION...AS WELL AS POTENTIAL COASTAL SURFACE LOW...MAY ALLOW MOISTURE TO START CREEPING IN AS EARLY AS FRIDAY AFTERNOON- NIGHT...BUT THE END RESULT DOES APPEAR TO BE COOL AND WET PERIODS INTO NEXT WEEKEND. BEFORE THEN...MAINLY DRY WITH TEMPERATURES SLIGHTLY BELOW CLIMATOLOGY THANKS TO FEED OF AIR FROM SURFACE HIGH PRESSURE IN QUEBEC. A FRONTAL ZONE WILL BE STALLED OUT NOT TOO FAR SOUTHEAST OF US...SO THAT WILL NEED TO BE MONITORED...BUT KEEPING FORECAST GENERALLY DRY FOR NOW WEDNESDAY NIGHT THROUGH THURSDAY NIGHT. && .AVIATION /16Z MONDAY THROUGH FRIDAY/... UPR WV GENERATE SOME LGT SHWRS THIS MRNG OVER THE ERN SITES WHILE LL MARINE MOISTURE CIRCULATES ARND THE NEW ENG HIPRES. THIS WILL RESULT IN A MVFR CIG OVER MUCH OF THE AREA...WHILE OCNL SHWRS DO NOT RESULT IN VSBY RESTRICTIONS. HTG SHD ALLOW VFR CIGS TO RETURN TO THE AREA IN THE LATE MRNG...WHILE THE WV PASSES LTR IN THE DAY BRINGING THE SHWRS WITH IT. LTR TNGT...MARINE LYR RETURNS THE MVFR CIGS TO MOST STATIONS. SLY OR SELY FLOW CONTS THRU THE PD. .OUTLOOK... TUES-TUES NGT...CHC -SHRA AND ASSOCIATED RESTRICTIONS. BEST CHANCE WITH FRONTAL PASSAGE TUE-TUE NGT. WEDNESDAY-FRIDAY...MAINLY VFR EXCEPT FOR LOCAL RESTRICTIONS DUE TO VALLEY FOG /MAINLY KELM/. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...NONE. NY...NONE. && $$ SYNOPSIS...HEDEN NEAR TERM...HEDEN/MLJ SHORT TERM...HEDEN LONG TERM...MDP AVIATION...DGM
AREA FORECAST DISCUSSION
NWS BUFFALO NY
943 AM EDT MON SEP 28 2015 .SYNOPSIS... A SOUTHERLY FLOW OF MOIST AIR WILL BRING SCATTERED SHOWERS TO THE ENTIRE REGION TODAY. MORE WIDESPREAD SHOWERS WILL MOVE INTO THE AREA TUESDAY WITH THE APPROACH OF A COLD FRONT. MUCH COOLER AND DRIER AIR WILL ARRIVE WEDNESDAY BEHIND THE FRONT AND LAST THROUGH THE END OF THE WEEK. && .NEAR TERM /THROUGH TONIGHT/... AN INCREASINGLY MOIST AIR MASS WILL FED INTO OUR REGION FROM THE OHIO VALLEY AND MID ATLANTIC STATES TODAY. AN AREA OF SCATTERED SHOWERS WILL PUSH ACROSS THE AREA TODAY AS A SUBTLE MID LEVEL VORTICITY MAXIMA MOVES NORTHWARD AND INCREASES LARGE SCALE ASCENT. LATEST HRRR QPF FIELDS SUGGESTING THAT THE BULK OF THE SHOWER ACTIVITY WILL OCCUR DURING THE FIRST HALF OF THE DAY AS THE UPPER SUPPORT CROSSES THE REGION FOLLOWED BY A DIMINISHING TREND THIS AFTERNOON AND TONIGHT. THE INCOMING WARMER AIRMASS WILL ALLOW HIGHS TO REACH THE LOWER TO MID 70S ON THE LAKE PLAINS TODAY WITH AN ADDED BOOST FROM A FAVORABLE DOWNSLOPE FLOW. THE HIGHER TERRAIN OF THE SOUTHERN TIER WILL STAY IN THE MID TO UPPER 60S WITH THICKER...LOWER CLOUD COVER. && .SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... LATEST GUIDANCE CONTINUES TO SHOW A SURFACE FRONT CROSSING THE REGION TUESDAY AND TUESDAY NIGHT. CURRENT FORECAST LOOKS GOOD AND WILL MAKE NO CHANGES. PREVIOUS DISCUSSION... A PLUME OF DEEP ATLANTIC MOISTURE CHARACTERIZED BY PRECIPITABLE WATER VALUES NEAR 1.5IN /MORE THAN 2SD ABOVE NORMAL/ WILL LIE ACROSS NEW YORK STATE INTO TUESDAY. THIS MOISTURE WILL BE CIRCULATING AROUND A HIGH PRESSURE CENTER OFF THE NEW ENGLAND COAST WHILE A BROAD 500MB TROUGH AND SURFACE COLD FRONT APPROACH FROM THE WESTERN GREAT LAKES. A COMBINATION OF SURFACE MOISTURE CONVERGENCE AND SERIES OF UPPER LEVEL VORTICITY MAXIMA EXITING THE BASE OF THE 500MB TROUGH WILL LIKELY CONTRIBUTE TO SEVERAL ROUNDS OF HIT AND MISS SHOWERS AND EXTENSIVE CLOUD COVER INTO TUESDAY AHEAD OF THE APPROACHING COLD FRONT. INSTABILITY AND SHEAR ARE FORECAST TO INCREASE TUESDAY AFTERNOON WITH CAPE VALUES RISING OVER 1000 J/KG AND BULK SHEAR OF 30-35 KTS. THIS SHOULD PROMOTE SOME THUNDERSTORM ACTIVITY AHEAD OF AND ALONG THE COLD FRONT AS IT IS FORECAST TO CROSS WESTERN AND CENTRAL NEW YORK TUESDAY AFTERNOON AND EVENING. THE HIGH MOISTURE AIRMASS WILL KEEP MILD TEMPERATURES IN PLACE WITH HIGHS ON TUESDAY INTO THE 70S WITH A BREEZY SOUTHERLY FLOW AHEAD OF THE COLD FRONT. DOWNSLOPING ACROSS THE ONTARIO LAKE PLAINS AND GENESEE RIVER VALLEY SHOULD SUPPORT MID 70S IN THESE WARMER LOCATIONS. A BROAD CANADIAN SURFACE HIGH WILL BUILD IN BEHIND THE COLD FRONT TUESDAY NIGHT THROUGH THE END OF THE WEEK. THIS WILL BRING A PUNCH OF DRY CONTINENTAL POLAR AIR SOUTH ACROSS THE GREAT LAKES CLEARING SKIES AND KNOCKING BACK TEMPERATURES TO MORE SEASONABLE LEVELS. THE INITIAL SURGE OF COLD ADVECTION RIGHT BEHIND THE FRONT WILL MIX GUSTY WINDS OF 20-30 MPH TO THE SURFACE OVERNIGHT TUESDAY INTO WEDNESDAY AND THE NORTHERLY FLOW ACROSS LAKE ONTARIO MAY LINGER LOW CLOUDS ACROSS WESTERN NEW YORK WITH CLEARING FIRST EAST OF LAKE ONTARIO. TEMPERATURES WILL FEEL MORE FALL-LIKE WEDNESDAY WITH HIGHS ONLY RISING INTO THE UPPER 50S TO LOWER 60S WITH DEWPOINTS SLIPPING BACK TO AROUND 40. LOWS WEDNESDAY NIGHT WILL SLIP TO THE MID TO UPPER 40S FOR LOWER ELEVATIONS AND URBAN AREAS...WITH LOW 40S TO UPPER 30S ACROSS HIGHER TERRAIN OF THE SOUTHERN TIER AND ACROSS THE EASTERN LAKE ONTARIO REGION. && .LONG TERM /THURSDAY THROUGH SUNDAY/... BROAD SURFACE HIGH PRESSURE WILL BE FOUND ACROSS THE GREAT LAKES AND EASTERN CANADA THROUGH THE END OF THE WEEK WHILE SPLIT SUBTROPICAL AND POLAR JETS DIG STACKED TROUGHS ACROSS EASTERN NORTH AMERICA. THIS PATTERN WILL KEEP SEASONABLY COOL AND DRY WEATHER IN PLACE ACROSS WESTERN AND NORTH CENTRAL NEW YORK THURSDAY AND FRIDAY. 12Z ECMWF AND GFS MODELS SHOW VASTLY DIFFERENT SOLUTIONS FOR THE WEATHER NEXT WEEKEND WITH BOTH MODELS SHOWING CUT OFF LOWS DEVELOPING. THE EC LOW JUST NORTH OF THE EASTERN GREAT LAKES KEEPS ATLANTIC MOISTURE EAST AND NORTH OF THE FORECAST AREA LEAVING WESTERN AND CENTRAL NEW YORK COOL BUT MAINLY DRY WHILE THE GFS LOW OVER THE SOUTHEAST STATES WOULD ADVECT DEEP ATLANTIC MOISTURE NORTH ACROSS OUR REGION WHICH WOULD YIELD WETTER AND WARMER WEATHER. THERE IS A LOT OF ROOM AND TIME FOR MODELS TO BECOME BETTER ALIGNED FOR NEXT WEEKEND SO JUST INCLUDED A SLIGHT CHANCE OF SHOWERS FOR NOW. HIGH TEMPERATURES THROUGH THE LONG TERM PERIOD LOOK TO ONLY TOP OUT AROUND 60 WITH COOL OVERNIGHT LOWS DIPPING INTO THE 40S. && .AVIATION /14Z MONDAY THROUGH FRIDAY/... MID LEVEL WAVE LIFTING UP FROM THE OHIO VALLEY GENERATING SHOWERS ACROSS THE AREA THIS MORNING. THIS HAS RESULTED IN DETERIORATING CONDITIONS WITH IFR VSBYS/CIGS AT KJHW AND MVFR CIGS AT KIAG. WHILE IFR CONDITIONS ARE ONLY EXPECTED ALONG THE SOUTHERN TIER...CONDITIONS WILL LIKELY REMAIN OR LOWER TO MVFR AS THE SHOWERS MOVE THROUGH THIS MORNING. VFR CONDITIONS SHOULD RETURN THIS AFTERNOON AND TONIGHT AS THE WAVE EXITS AND THE SHOWER ACTIVITY DIMINISHES. OUTLOOK... TUESDAY...VFR/MVFR WITH SHOWERS LIKELY AND POSSIBLY A THUNDERSTORM. WEDNESDAY THROUGH FRIDAY...VFR. && .MARINE... SOUTHERLY WINDS MOSTLY IN THE 10 TO 15 KNOT RANGE WILL CONTINUE TODAY...THROUGH AT LEAST THE FIRST PART OF TUESDAY AS HIGH PRESSURE WILL BE LARGELY ANCHORED OFF THE NEW ENGLAND COAST. WHILE SOME AREAS OVER THE OPEN WATERS OF BOTH LAKES WILL SEE WINDS INCREASING TO THE 15-20 KNOT RANGE FOR A PERIOD TODAY...THE RESULTANT HIGHER WAVES WILL PREDOMINANTLY REMAIN OVER CANADIAN WATERS. AFTER THAT...A COLD FRONT WILL THEN CROSS THE LOWER LAKES TUESDAY AFTERNOON AND EVENING. INCREASING NORTHERLIES BEHIND THIS FRONT WILL LIKELY BRING A ROUND OF ADVISORY CONDITIONS TO BOTH LAKES FOR THE MIDDLE OF THE WEEK. && .BUF WATCHES/WARNINGS/ADVISORIES... NY...NONE. MARINE...NONE. && $$ SYNOPSIS...TMA NEAR TERM...TMA SHORT TERM...FRANKLIN/WCH LONG TERM...SMITH AVIATION...TMA MARINE...TMA
AREA FORECAST DISCUSSION
NWS BUFFALO NY
725 AM EDT MON SEP 28 2015 .SYNOPSIS... A SOUTHERLY FLOW OF MOIST AIR WILL BRING SCATTERED SHOWERS TO THE ENTIRE REGION TODAY. MORE WIDESPREAD SHOWERS WILL MOVE INTO THE AREA TUESDAY WITH THE APPROACH OF A COLD FRONT. MUCH COOLER AND DRIER AIR WILL ARRIVE WEDNESDAY BEHIND THE FRONT AND LAST THROUGH THE END OF THE WEEK. && .NEAR TERM /THROUGH TONIGHT/... AN INCREASINGLY MOIST AIR MASS WILL FED INTO OUR REGION FROM THE OHIO VALLEY AND MID ATLANTIC STATES TODAY. AN AREA OF SCATTERED SHOWERS WILL PUSH ACROSS THE AREA TODAY AS A SUBTLE MID LEVEL VORTICITY MAXIMA MOVES NORTHWARD AND INCREASES LARGE SCALE ASCENT. LATEST HRRR QPF FIELDS SUGGESTING THAT THE BULK OF THE SHOWER ACTIVITY WILL OCCUR DURING THE FIRST HALF OF THE DAY AS THE UPPER SUPPORT CROSSES THE REGION FOLLOWED BY A DIMINISHING TREND THIS AFTERNOON AND TONIGHT. THE INCOMING WARMER AIRMASS WILL ALLOW HIGHS TO REACH THE LOWER TO MID 70S ON THE LAKE PLAINS TODAY WITH AN ADDED BOOST FROM A FAVORABLE DOWNSLOPE FLOW. THE HIGHER TERRAIN OF THE SOUTHERN TIER WILL STAY IN THE MID TO UPPER 60S WITH THICKER...LOWER CLOUD COVER. && .SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... A PLUME OF DEEP ATLANTIC MOISTURE CHARACTERIZED BY PRECIPITABLE WATER VALUES NEAR 1.5IN /MORE THAN 2SD ABOVE NORMAL/ WILL LIE ACROSS NEW YORK STATE INTO TUESDAY. THIS MOISTURE WILL BE CIRCULATING AROUND A HIGH PRESSURE CENTER OFF THE NEW ENGLAND COAST WHILE A BROAD 500MB TROUGH AND SURFACE COLD FRONT APPROACH FROM THE WESTERN GREAT LAKES. A COMBINATION OF SURFACE MOISTURE CONVERGENCE AND SERIES OF UPPER LEVEL VORTICITY MAXIMA EXITING THE BASE OF THE 500MB TROUGH WILL LIKELY CONTRIBUTE TO SEVERAL ROUNDS OF HIT AND MISS SHOWERS AND EXTENSIVE CLOUD COVER INTO TUESDAY AHEAD OF THE APPROACHING COLD FRONT. INSTABILITY AND SHEAR ARE FORECAST TO INCREASE TUESDAY AFTERNOON WITH CAPE VALUES RISING OVER 1000 J/KG AND BULK SHEAR OF 30-35 KTS. THIS SHOULD PROMOTE SOME THUNDERSTORM ACTIVITY AHEAD OF AND ALONG THE COLD FRONT AS IT IS FORECAST TO CROSS WESTERN AND CENTRAL NEW YORK TUESDAY AFTERNOON AND EVENING. THE HIGH MOISTURE AIRMASS WILL KEEP MILD TEMPERATURES IN PLACE WITH HIGHS ON TUESDAY INTO THE 70S WITH A BREEZY SOUTHERLY FLOW AHEAD OF THE COLD FRONT. DOWNSLOPING ACROSS THE ONTARIO LAKE PLAINS AND GENESEE RIVER VALLEY SHOULD SUPPORT MID 70S IN THESE WARMER LOCATIONS. A BROAD CANADIAN SURFACE HIGH WILL BUILD IN BEHIND THE COLD FRONT TUESDAY NIGHT THROUGH THE END OF THE WEEK. THIS WILL BRING A PUNCH OF DRY CONTINENTAL POLAR AIR SOUTH ACROSS THE GREAT LAKES CLEARING SKIES AND KNOCKING BACK TEMPERATURES TO MORE SEASONABLE LEVELS. THE INITIAL SURGE OF COLD ADVECTION RIGHT BEHIND THE FRONT WILL MIX GUSTY WINDS OF 20-30 MPH TO THE SURFACE OVERNIGHT TUESDAY INTO WEDNESDAY AND THE NORTHERLY FLOW ACROSS LAKE ONTARIO MAY LINGER LOW CLOUDS ACROSS WESTERN NEW YORK WITH CLEARING FIRST EAST OF LAKE ONTARIO. TEMPERATURES WILL FEEL MORE FALL-LIKE WEDNESDAY WITH HIGHS ONLY RISING INTO THE UPPER 50S TO LOWER 60S WITH DEWPOINTS SLIPPING BACK TO AROUND 40. LOWS WEDNESDAY NIGHT WILL SLIP TO THE MID TO UPPER 40S FOR LOWER ELEVATIONS AND URBAN AREAS...WITH LOW 40S TO UPPER 30S ACROSS HIGHER TERRAIN OF THE SOUTHERN TIER AND ACROSS THE EASTERN LAKE ONTARIO REGION. && .LONG TERM /THURSDAY THROUGH SUNDAY/... BROAD SURFACE HIGH PRESSURE WILL BE FOUND ACROSS THE GREAT LAKES AND EASTERN CANADA THROUGH THE END OF THE WEEK WHILE SPLIT SUBTROPICAL AND POLAR JETS DIG STACKED TROUGHS ACROSS EASTERN NORTH AMERICA. THIS PATTERN WILL KEEP SEASONABLY COOL AND DRY WEATHER IN PLACE ACROSS WESTERN AND NORTH CENTRAL NEW YORK THURSDAY AND FRIDAY. 12Z ECMWF AND GFS MODELS SHOW VASTLY DIFFERENT SOLUTIONS FOR THE WEATHER NEXT WEEKEND WITH BOTH MODELS SHOWING CUT OFF LOWS DEVELOPING. THE EC LOW JUST NORTH OF THE EASTERN GREAT LAKES KEEPS ATLANTIC MOISTURE EAST AND NORTH OF THE FORECAST AREA LEAVING WESTERN AND CENTRAL NEW YORK COOL BUT MAINLY DRY WHILE THE GFS LOW OVER THE SOUTHEAST STATES WOULD ADVECT DEEP ATLANTIC MOISTURE NORTH ACROSS OUR REGION WHICH WOULD YIELD WETTER AND WARMER WEATHER. THERE IS A LOT OF ROOM AND TIME FOR MODELS TO BECOME BETTER ALIGNED FOR NEXT WEEKEND SO JUST INCLUDED A SLIGHT CHANCE OF SHOWERS FOR NOW. HIGH TEMPERATURES THROUGH THE LONG TERM PERIOD LOOK TO ONLY TOP OUT AROUND 60 WITH COOL OVERNIGHT LOWS DIPPING INTO THE 40S. && .AVIATION /11Z MONDAY THROUGH FRIDAY/... MID LEVEL WAVE LIFTING UP FROM THE OHIO VALLEY GENERATING SHOWERS ACROSS THE AREA THIS MORNING. THIS HAS RESULTED IN DETERIORATING CONDITIONS WITH IFR VSBYS/CIGS AT KJHW AND MVFR CIGS AT KIAG. WHILE IFR CONDITIONS ARE ONLY EXPECTED ALONG THE SOUTHERN TIER...CONDITIONS WILL LIKELY REMAIN OR LOWER TO MVFR AS THE SHOWERS MOVE THROUGH THIS MORNING. VFR CONDITIONS SHOULD RETURN THIS AFTERNOON AND TONIGHT AS THE WAVE EXITS AND THE SHOWER ACTIVITY DIMINISHES. OUTLOOK... TUESDAY...VFR/MVFR WITH SHOWERS LIKELY AND POSSIBLY A THUNDERSTORM. WEDNESDAY THROUGH FRIDAY...VFR. && .MARINE... SOUTHERLY WINDS MOSTLY IN THE 10 TO 15 KNOT RANGE WILL CONTINUE TODAY...THROUGH AT LEAST THE FIRST PART OF TUESDAY AS HIGH PRESSURE WILL BE LARGELY ANCHORED OFF THE NEW ENGLAND COAST. WHILE SOME AREAS OVER THE OPEN WATERS OF BOTH LAKES WILL SEE WINDS INCREASING TO THE 15-20 KNOT RANGE FOR A PERIOD TODAY...THE RESULTANT HIGHER WAVES WILL PREDOMINANTLY REMAIN OVER CANADIAN WATERS. AFTER THAT...A COLD FRONT WILL THEN CROSS THE LOWER LAKES TUESDAY AFTERNOON AND EVENING. INCREASING NORTHERLIES BEHIND THIS FRONT WILL LIKELY BRING A ROUND OF ADVISORY CONDITIONS TO BOTH LAKES FOR THE MIDDLE OF THE WEEK. && .BUF WATCHES/WARNINGS/ADVISORIES... NY...NONE. MARINE...NONE. && $$ SYNOPSIS...TMA NEAR TERM...TMA SHORT TERM...WCH LONG TERM...SMITH AVIATION...TMA MARINE...TMA
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
646 AM EDT MON SEP 28 2015 .SYNOPSIS... SHOWERS WILL BE POSSIBLE TODAY, MAINLY OVER THE FINGER LAKES AND CENTRAL NEW YORK. SHOWERS WILL BECOME MORE LIKELY ON TUESDAY INTO WEDNESDAY, AS A COLD FRONT PUSHES INTO THE REGION. && .NEAR TERM /THROUGH TONIGHT/... 400 AM UPDATE... AFTER GETTING LUCKY FOR MOST OF THE AREA LAST NIGHT BEING CLEAR ENOUGH TO VIEW THE ECLIPSE, REALITY IS SETTING IN WITH THICK CLOUDS ON OUR DOORSTEPS WITH SOME SHOWERS NOT FAR BEHIND. FOLLOWED LATEST HRRR QPF FIELDS AND INCREASED TO LIKELY POPS THROUGH MID MORNING FROM THE WESTERN SOUTHERN TIER UP THROUGH FINGER LAKES. PRECIP SHOULD MAKE IT TO CNY BUT MAY BREAK UP A BIT BY THE TIME THAT HAPPENS. LATER TODAY AND THROUGH TONIGHT RAIN CHANCES DON`T LOOK ALL THAT GREAT BUT WE CAN`T RULE ANYTHING OUT, ESPECIALLY IN PRETTY MUCH THE SAME AREAS JUST MENTIONED ABOVE. FARTHER SOUTH ESPECIALLY INTO PA, MAINLY DRY WEATHER IS EXPECTED. && .SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... 4 AM UPDATE... ALTHOUGH MY GARDEN IS WINDING DOWN DUE TO THE LOSS OF DAYLIGHT/LOW SUN ANGLE, I AM GETTING EXCITED ABOUT THE POSSIBILITY OF SOME RAIN AROUND HERE! RAIN CHANCES GO UP FOR OUR AREA BY TUESDAY AFTERNOON AS A COLD FRONT APPROACHES. CONTINUE TO MENTION SOME ISOLATED THUNDER THROUGH EARLY TUESDAY NIGHT TO MATCH WELL WITH OTHER OFFICES ALONG WITH THE FACT LI`S ARE NEAR OR BELOW ZERO. UNLIKE PAST RAIN EVENTS WITH EACH MODEL RUN WE ARE LOOKING AT INCREASING CHANCES FOR HIGHER RAINFALL AMOUNTS INSTEAD OF LOWER ONES. IN FACT THE MAIN TREND OF THE 0Z RUNS OF BOTH THE EURO AND GFS NOT ONLY RAISE RAINFALL AMOUNTS, THE PROGRESSION OF THE COLD FRONT THROUGH OUR AREA IS MUCH SLOWER. ACCORDINGLY I RAISED POPS ABOVE 70% FOR THE ENTIRE AREA TUESDAY NIGHT. IN FACT THROUGH MUCH OF WEDNESDAY NOW, WE HAVE POPS ABOVE 60% FROM NEAR BINGHAMTON SOUTH AND EAST. DRIER WEATHER NOW HOLDS OFF UNTIL WED NIGHT. AT EARLY LOOK AT TOTAL RAINFALL AMOUNTS WOULD BE A HALF OF AN INCH UP ACROSS THE FINGER LAKES, BUT EXCEEDING AN INCH FROM NEAR BINGHAMTON SOUTH AND EAST, WHERE PRECIP LINGERS THE LONGEST. && .LONG TERM /THURSDAY THROUGH SUNDAY/... 200 PM SUNDAY UPDATE... THOUGH DIFFERING ON DETAILS...MODELS ARE STARTING TO GET INTO BETTER LARGE SCALE AGREEMENT...ON THE IDEA OF AN UNSETTLED TROUGHY PATTERN TAKING SHAPE BY NEXT WEEKEND. ONSHORE FLOW...CUTOFF LOW EVOLUTION...AS WELL AS POTENTIAL COASTAL SURFACE LOW...MAY ALLOW MOISTURE TO START CREEPING IN AS EARLY AS FRIDAY AFTERNOON- NIGHT...BUT THE END RESULT DOES APPEAR TO BE COOL AND WET PERIODS INTO NEXT WEEKEND. BEFORE THEN...MAINLY DRY WITH TEMPERATURES SLIGHTLY BELOW CLIMATOLOGY THANKS TO FEED OF AIR FROM SURFACE HIGH PRESSURE IN QUEBEC. A FRONTAL ZONE WILL BE STALLED OUT NOT TOO FAR SOUTHEAST OF US...SO THAT WILL NEED TO BE MONITORED...BUT KEEPING FORECAST GENERALLY DRY FOR NOW WEDNESDAY NIGHT THROUGH THURSDAY NIGHT. && .AVIATION /12Z MONDAY THROUGH FRIDAY/... UPR WV GENERATE SOME LGT SHWRS THIS MRNG OVER THE ERN SITES WHILE LL MARINE MOISTURE CIRCULATES ARND THE NEW ENG HIPRES. THIS WILL RESULT IN A MVFR CIG OVER MUCH OF THE AREA...WHILE OCNL SHWRS DO NOT RESULT IN VSBY RESTRICTIONS. HTG SHD ALLOW VFR CIGS TO RETURN TO THE AREA IN THE LATE MRNG...WHILE THE WV PASSES LTR IN THE DAY BRINGING THE SHWRS WITH IT. LTR TNGT...MARINE LYR RETURNSRETURNING THE MVFR CIGS TO MOST STATIONS. SLY OR SELY FLOW CONTS THRU THE PD. .OUTLOOK... TUES-TUES NGT...CHC -SHRA AND ASSOCIATED RESTRICTIONS. BEST CHANCE WITH FRONTAL PASSAGE TUE-TUE NGT. WEDNESDAY-FRIDAY...MAINLY VFR EXCEPT FOR LOCAL RESTRICTIONS DUE TO VALLEY FOG /MAINLY KELM/. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...NONE. NY...NONE. && $$ SYNOPSIS...HEDEN NEAR TERM...HEDEN SHORT TERM...HEDEN LONG TERM...MDP AVIATION...DGM
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1037 AM EDT MON SEP 28 2015 .SYNOPSIS...DEEP ATLANTIC MOISTURE WILL CONTINUE TO PUMP INTO THE REGION TODAY... BETWEEN CANADIAN HIGH PRESSURE TO OUR NORTHEAST AND LOW PRESSURE JUST OFF THE SOUTHEAST COAST. THESE FEATURES WILL WEAKEN TONIGHT INTO TUESDAY... RESULTING IN A BRIEF IMPROVEMENT IN WEATHER CONDITIONS... HOWEVER A SURGE OF GULF MOISTURE AHEAD OF AN APPROACHING COLD FRONT WILL BRING A RETURN TO WET AND UNSETTLED WEATHER LATE TUESDAY THROUGH THURSDAY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 1030 AM MONDAY... NO MAJOR CHANGES TO THE FORECAST THIS MORNING. VERY MOIST AIR MASS REMAINS IN PLACE OVER THE REGION...WITH PWAT VALUES NEAR 2 INCHES PER THE BLENDED TPW IMAGERY. A WEAK WAVE IS PROGGED TO TRACK NORTHEASTWARD OVER EASTERN NC THIS AFTERNOON AND GIVEN SOME WEAK DESTABILIZATION (ALREADY SEEING THIS ACROSS EASTERN NC PER THE SPC MESOSCALE ANALYSIS)...PRECIP CHANCES WILL INCREASE THROUGH THE LATE MORNING/EARLY AFTERNOON HOURS FROM EAST TO WEST (FOLLOWED THE HRRR CLOSELY FOR THE TIMING). THIS AREA OF RAIN/SHOWERS SHOULD GRADUALLY TRANSLATE ACROSS THE FORECAST AREA...WITH THE COASTAL PLAIN SEEING THE BEST CHANCE OF RAIN IN THE NEXT FEW HOURS AND FURTHER WEST BY MID/LATE AFTERNOON. PRECIP SHOULD DIMINISH THROUGH THE EVENING HOURS...BUT LIGHT RAIN/DRIZZLE WILL BE POSSIBLE OVERNIGHT (AS HAS BEEN THE CASE THE LAST SEVERAL DAYS). PREVIOUS DISCUSSION AS OF 3 AM...COLUMN REMAINS VERY MOIST THIS MORNING... ALTHOUGH THE EXTENT OF MOISTURE THROUGH THE COLUMN IS NOT QUITE WHAT IT`S BEEN THE LAST COUPLE OF DAYS. WE`RE IN GRADUAL TRANSITION AWAY FROM THE DYING WEDGE REGIME TO AN ATYPICALLY HUMID (ESP FOR LATE SEPTEMBER) AIR MASS. THE PARENT HIGH WHICH BROUGHT THE DAMMING OVER THE WEEKEND IS NOW CENTERED WELL OUT OVER THE NW ATLANTIC YET STILL NOSING WEST AND SW INTO THE WRN CAROLINAS. THE STABLE POOL OVER THE WRN PIEDMONT HAS WEAKENED... AND THE AIR MASS HAS BECOME MORE HOMOGENEOUS ACROSS THE CWA... DEMONSTRATED BY TEMP/DEWPOINT RANGES OF JUST AROUND 4 DEGREES ACROSS CENTRAL NC... AND UNIFORM OBSERVED LIFTED INDICES AND CINH. MUCH OF THIS PAST EVENING`S LIGHT PRECIP DRIVEN BY ISENTROPIC UPGLIDE HAS SHIFTED WELL NW OUT OF THE AREA... LEAVING JUST WIDESPREAD STRATUS AND PERHAPS A FEW ISOLATED DRIZZLE PATCHES. THIS RELATIVE LULL IN PRECIP WILL CONTINUE THROUGH THE MID MORNING HOURS... HOWEVER AREAS OF SHOWERS NOW JUST OFF THE NC COAST ARE ON TRACK TO TRANSLATE WEST OR WNW INTO THE COASTAL PLAIN AND THEN INTO THE PIEDMONT FROM MID/LATE MORNING THROUGH THE AFTERNOON... WITH COVERAGE FILLING IN AS HEATING ALLOWS FOR A FEW HOLES IN THE CLOUDS AND SUBSEQUENT (WEAK) DESTABILIZATION... WITH LIFT POTENTIALLY AUGMENTED BY A WEAK WAVE TRACKING NE OVER ERN NC THIS AFTERNOON. EXPECT LOW POPS THIS MORNING... TRENDING UP TO LIKELY EAST AND CHANCE WEST... WITH HIGHER POPS THEN PUSHING WNW INTO THE WRN PIEDMONT AS WE GET INTO THE EVENING HOURS... A PATTERN SUGGESTED BY RECENT RUNS OF BOTH LARGE SCALE AND CONVECTION ALLOWING MODELS INCLUDING THE SREF/GFS/3 KM NAMRR AND THE LATEST HRRR RUNS. FORECAST SOUNDINGS SHOW A DEEP WARM LAYER THIS AFTERNOON WITH AN LCL-TO-FREEZING-LEVEL DEPTH OVER 4 KM... ALONG WITH PW VALUES OF 2.0-2.3 INCHES... SO ANY SHOWERS FORMING TODAY WILL BE CAPABLE OF DROPPING BRIEF HEAVY RAIN. FORECAST MUCAPE FOR TODAY IS UNIMPRESSIVE (UNDER 1000 J/KG... MOST OF WHICH IS BELOW THE -10C LEVEL) WITH GENERALLY SUB-20-KT DEEP LAYER BULK SHEAR... SO WILL NOT MENTION THUNDER AT THIS TIME... ALTHOUGH A STRIKE OR TWO IS CERTAINLY POSSIBLE IN THE COASTAL PLAIN. EXPECT THE AREA OF BETTER SHOWER COVERAGE TO CONTINUE SHIFTING WNW TOWARD THE FOOTHILLS DURING THE EVENING... SO WILL TREND POPS DOWN FROM EAST TO WEST TONIGHT... RESULTING IN 30-40% CHANCES NORTHWEST TRANSITIONING DOWN TO JUST ISOLATED SHOWERS EAST OF HIGHWAY 1 OVERNIGHT. STRATUS REDEVELOPMENT APPEARS LIKELY LATE TONIGHT GIVEN THE LOW LEVEL MOISTURE AND TRAJECTORIES ALONG WITH PERSISTENCE... ALTHOUGH A LIGHT BREEZE FROM THE NE -- AS MODELS SUGGEST -- MAY INHIBIT FOG DEVELOPMENT. WILL LEAVE IN A MENTION OF PATCHY FOG FOR NOW. EXPECT HIGHS FROM THE MID 70S NW (WHERE THE AIR IS STILL A BIT MORE STABLE AND MORE RESISTANT TO MIXING AND THUS SHOULD SEE LESS SUNSHINE) TO AROUND 80-82 EAST OF HIGHWAY 1... WITH MOSTLY CLOUDY SKIES. MILD LOWS TONIGHT OF 67-71... AROUND 10 DEG ABOVE NORMAL. -GIH && .SHORT TERM /TUESDAY THROUGH TUESDAY NIGHT/... AS OF 330 AM MONDAY... CONTINUED MOIST WITH A GOOD CHANCE OF SHOWERS... AND PERHAPS A STORM OR TWO. THE MID LEVEL TROUGH FROM THE LOWER GREAT LAKES THROUGH THE LOWER MISS VALLEY TO LA WILL CONTINUE TO TILT SLOWLY... RESULTING IN A GRADUAL INCREASE IN MID LEVEL VORTICITY MOVING FROM THE NW GULF INTO THE CAROLINAS ON WEAK SOUTHWESTERLY MID LEVEL FLOW. THE LOW LEVEL ATLANTIC INFLOW SHOULD BE ON THE DECREASE WITH A REDUCED FETCH... A FUNCTION OF WHAT IS NOW TD #11 AS IT PUSHES SLOWLY NW/NNW ON ITS ANTICIPATED TRACK TOWARD THE OFFSHORE WATERS OF NC. PW IS PROJECTED TO REMAIN VERY HIGH AT 2.0-2.3 INCHES... WELL ABOVE SEASONAL NORMALS... AND MODELS SHOW SLIGHTLY BETTER POTENTIAL FOR INSTABILITY TUE AFTERNOON WITHIN PERSISTENT HIGH THETA-E ADVECTION IN THE LOW LEVELS. DESPITE THE WEAK WIND FIELD AND MARGINAL DPVA... WE SHOULD SEE DECENT UPPER DIVERGENCE OVER THE AREA IN THE LEFT EXIT REGION OF THE BROAD JET FROM THE GULF INTO THE TN VALLEY. WILL TREND POPS UP TO LIKELY OVER MUCH OF THE CWA BY AFTERNOON... WANING GRADUALLY IN THE EVENING/NIGHTTIME BUT STAYING AT 30-50%... WITH BETTER SHOWER CHANCES SHIFTING WNW INTO THE NW PIEDMONT AND FOOTHILLS WITH TIME. SLIGHTLY BETTER CAPE AND SHEAR ARE EXPECTED... STILL MARGINAL THOUGH... SO HAVE INCLUDED JUST A MENTION OF ISOLATED THUNDER IN THE AFTERNOON. HIGHS 75-83 AND LOWS 66-71... BOTH ABOVE NORMAL... WITH MOSTLY CLOUDY SKIES HOLDING FIRM. -GIH && .LONG TERM /WEDNESDAY THROUGH SUNDAY/... AS OF 327 AM MONDAY... UNCERTAINTY IN THE FORECAST IS ABOUT AS HIGH AS CAN BE ADVERTISED FROM MID WEEK INTO THE WEEKEND. THE OPERATIONAL MODELS CONTINUE TO SHOW PLENTY OF SPREAD AND EVEN THE ENSEMBLE MEANS ARE CONFLICTING ON THE PLACEMENT OF THE IMPORTANT WEATHER PRODUCING SYSTEMS. THE MAIN WEATHER HAZARDS SHOULD BE LIMITED TO A LOW END HEAVY RAIN THREAT... BUT SIGNIFICANT RAINFALL MAY BE MORE OF A HELP TO CURRENT DROUGHT STATUS THAN IT WOULD BE A THREAT FOR FLOODING. THE QPF MID TO LATE WEEK IS THE MAIN QUESTION AS ABOUT 30 PERCENT OF THE MODELS INDICATE THE HEAVIEST RAIN INLAND WITH OVERRUNNING RAINS AGAIN THU NIGHT INTO SATURDAY... WHICH 70 PERCENT OF THE MODELS SUPPORT THE HEAVY SWATH OF QPF ALONG OR JUST OFF THE MID-ATLANTIC COAST. ONE THING SEEMS TO BE MORE CERTAIN SHOULD BE THE COOLER TEMPERATURES AGAIN AS ANOTHER STRONG SURFACE HIGH IS EXPECTED TO BUILD SOUTH INTO NC/SC THURSDAY INTO THE WEEKEND. THIS OCCURS AS A TROUGH ALOFT AND LINGERING LOW LEVEL BOUNDARY CONTINUE TO BE FORECAST BY MOST MODELS TO BRING A CONTINUATION OF THE UNSETTLED PATTERN THAT BEGAN LATE LAST WEEK. A RETURN TO A PROLONGED NE FLOW... CONSIDERABLE CLOUDINESS... AND POSSIBLY SIGNIFICANT RAIN IS EXPECTED THU-SAT. && .AVIATION /12Z MONDAY THROUGH FRIDAY/... AS OF 640 AM MONDAY... MOIST AND DEEP LOW LEVEL FLOW FROM THE EAST WILL CONTINUE TO BRING MOSTLY ADVERSE AVIATION CONDITIONS TODAY... ESPECIALLY AT INT/GSO... WHERE IFR/LIFR CIGS AND MVFR/IFR VSBYS ARE LIKELY TO HOLD THROUGH 14Z... ALONG WITH PATCHY DRIZZLE. FARTHER EAST AT RDU/RWI/FAY... MVFR CIGS SHOULD HOLD THROUGH 14Z... ALTHOUGH A SHORT PERIOD OF IFR IS POSSIBLE. SOON AFTER 14Z... CIGS AT ALL LOCATIONS SHOULD SLOWLY BEGIN TO LIFT THROUGH THE MVFR CATEGORY... LASTING UNTIL AROUND 18Z OR 19Z WHEN SOME BREAKS IN THE CLOUDS ARE EXPECTED... ALTHOUGH ANY SCT/BKN CLOUDS ARE STILL LIKELY TO BE BASED AT 2500-3000 FT AGL. A TREND BACK TO MVFR TO IFR CIGS IS EXPECTED BY MID EVENING (AFTER 00Z TUE)... LASTING THROUGH TONIGHT... WITH POTENTIAL IFR/LIFR FOG FORMING OVERNIGHT. A FEW SHOWERS ARE POSSIBLE ESPECIALLY THIS AFTERNOON AND THESE COULD PRODUCE A PERIOD OF SUB-VFR VSBYS. LOOKING BEYOND 12Z TUE: IFR CONDITIONS ARE EXPECTED TO RULE THROUGH DAYBREAK TUE... ALTHOUGH RWI MAY STAY MVFR FOR MUCH OF THE NIGHT WITH PATCHY FOG. INT/GSO SHOULD STAY MVFR THROUGH TUE BUT RDU/RWI/FAY SHOULD LIFT TO MVFR THEN PERHAPS LOW-END VFR TUE AFTERNOON. IFR/LIFR CONDITIONS IN FOG ARE EXPECTED TO RETURN LATE TUE EVENING THROUGH DAYBREAK WED. VFR CONDITIONS THROUGH MIDDAY WED BUT SHOWERS/STORMS AHEAD OF A COLD FRONT MAY BRING SUB-VFR CONDITIONS WED/WED NIGHT. THIS FRONT WILL MOVE THROUGH WED NIGHT AND STALL TO OUR SE INTO FRI... POTENTIALLY BRINGING A RETURN TO PREDOMINANTLY POOR AVIATION CONDITIONS WITHIN AREAS OF RAIN/DRIZZLE. -GIH && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...HARTFIELD NEAR TERM...KRD/HARTFIELD SHORT TERM...HARTFIELD LONG TERM...BADGETT AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS RALEIGH NC
640 AM EDT MON SEP 28 2015 .SYNOPSIS...DEEP ATLANTIC MOISTURE WILL CONTINUE TO PUMP INTO THE REGION TODAY... BETWEEN CANADIAN HIGH PRESSURE TO OUR NORTHEAST AND LOW PRESSURE JUST OFF THE SOUTHEAST COAST. THESE FEATURES WILL WEAKEN TONIGHT INTO TUESDAY... RESULTING IN A BRIEF IMPROVEMENT IN WEATHER CONDITIONS... HOWEVER A SURGE OF GULF MOISTURE AHEAD OF AN APPROACHING COLD FRONT WILL BRING A RETURN TO WET AND UNSETTLED WEATHER LATE TUESDAY THROUGH THURSDAY. && .NEAR TERM /TODAY THROUGH TONIGHT/... AS OF 320 AM MONDAY... COLUMN REMAINS VERY MOIST THIS MORNING... ALTHOUGH THE EXTENT OF MOISTURE THROUGH THE COLUMN IS NOT QUITE WHAT IT`S BEEN THE LAST COUPLE OF DAYS. WE`RE IN GRADUAL TRANSITION AWAY FROM THE DYING WEDGE REGIME TO AN ATYPICALLY HUMID (ESP FOR LATE SEPTEMBER) AIR MASS. THE PARENT HIGH WHICH BROUGHT THE DAMMING OVER THE WEEKEND IS NOW CENTERED WELL OUT OVER THE NW ATLANTIC YET STILL NOSING WEST AND SW INTO THE WRN CAROLINAS. THE STABLE POOL OVER THE WRN PIEDMONT HAS WEAKENED... AND THE AIR MASS HAS BECOME MORE HOMOGENEOUS ACROSS THE CWA... DEMONSTRATED BY TEMP/DEWPOINT RANGES OF JUST AROUND 4 DEGREES ACROSS CENTRAL NC... AND UNIFORM OBSERVED LIFTED INDICES AND CINH. MUCH OF THIS PAST EVENING`S LIGHT PRECIP DRIVEN BY ISENTROPIC UPGLIDE HAS SHIFTED WELL NW OUT OF THE AREA... LEAVING JUST WIDESPREAD STRATUS AND PERHAPS A FEW ISOLATED DRIZZLE PATCHES. THIS RELATIVE LULL IN PRECIP WILL CONTINUE THROUGH THE MID MORNING HOURS... HOWEVER AREAS OF SHOWERS NOW JUST OFF THE NC COAST ARE ON TRACK TO TRANSLATE WEST OR WNW INTO THE COASTAL PLAIN AND THEN INTO THE PIEDMONT FROM MID/LATE MORNING THROUGH THE AFTERNOON... WITH COVERAGE FILLING IN AS HEATING ALLOWS FOR A FEW HOLES IN THE CLOUDS AND SUBSEQUENT (WEAK) DESTABILIZATION... WITH LIFT POTENTIALLY AUGMENTED BY A WEAK WAVE TRACKING NE OVER ERN NC THIS AFTERNOON. EXPECT LOW POPS THIS MORNING... TRENDING UP TO LIKELY EAST AND CHANCE WEST... WITH HIGHER POPS THEN PUSHING WNW INTO THE WRN PIEDMONT AS WE GET INTO THE EVENING HOURS... A PATTERN SUGGESTED BY RECENT RUNS OF BOTH LARGE SCALE AND CONVECTION ALLOWING MODELS INCLUDING THE SREF/GFS/3 KM NAMRR AND THE LATEST HRRR RUNS. FORECAST SOUNDINGS SHOW A DEEP WARM LAYER THIS AFTERNOON WITH AN LCL-TO- FREEZING-LEVEL DEPTH OVER 4 KM... ALONG WITH PW VALUES OF 2.0-2.3 INCHES... SO ANY SHOWERS FORMING TODAY WILL BE CAPABLE OF DROPPING BRIEF HEAVY RAIN. FORECAST MUCAPE FOR TODAY IS UNIMPRESSIVE (UNDER 1000 J/KG... MOST OF WHICH IS BELOW THE -10C LEVEL) WITH GENERALLY SUB-20-KT DEEP LAYER BULK SHEAR... SO WILL NOT MENTION THUNDER AT THIS TIME... ALTHOUGH A STRIKE OR TWO IS CERTAINLY POSSIBLE IN THE COASTAL PLAIN. EXPECT THE AREA OF BETTER SHOWER COVERAGE TO CONTINUE SHIFTING WNW TOWARD THE FOOTHILLS DURING THE EVENING... SO WILL TREND POPS DOWN FROM EAST TO WEST TONIGHT... RESULTING IN 30-40% CHANCES NORTHWEST TRANSITIONING DOWN TO JUST ISOLATED SHOWERS EAST OF HIGHWAY 1 OVERNIGHT. STRATUS REDEVELOPMENT APPEARS LIKELY LATE TONIGHT GIVEN THE LOW LEVEL MOISTURE AND TRAJECTORIES ALONG WITH PERSISTENCE... ALTHOUGH A LIGHT BREEZE FROM THE NE -- AS MODELS SUGGEST -- MAY INHIBIT FOG DEVELOPMENT. WILL LEAVE IN A MENTION OF PATCHY FOG FOR NOW. EXPECT HIGHS FROM THE MID 70S NW (WHERE THE AIR IS STILL A BIT MORE STABLE AND MORE RESISTANT TO MIXING AND THUS SHOULD SEE LESS SUNSHINE) TO AROUND 80-82 EAST OF HIGHWAY 1... WITH MOSTLY CLOUDY SKIES. MILD LOWS TONIGHT OF 67-71... AROUND 10 DEG ABOVE NORMAL. -GIH && .SHORT TERM /TUESDAY THROUGH TUESDAY NIGHT/... AS OF 330 AM MONDAY... CONTINUED MOIST WITH A GOOD CHANCE OF SHOWERS... AND PERHAPS A STORM OR TWO. THE MID LEVEL TROUGH FROM THE LOWER GREAT LAKES THROUGH THE LOWER MISS VALLEY TO LA WILL CONTINUE TO TILT SLOWLY... RESULTING IN A GRADUAL INCREASE IN MID LEVEL VORTICITY MOVING FROM THE NW GULF INTO THE CAROLINAS ON WEAK SOUTHWESTERLY MID LEVEL FLOW. THE LOW LEVEL ATLANTIC INFLOW SHOULD BE ON THE DECREASE WITH A REDUCED FETCH... A FUNCTION OF WHAT IS NOW TD #11 AS IT PUSHES SLOWLY NW/NNW ON ITS ANTICIPATED TRACK TOWARD THE OFFSHORE WATERS OF NC. PW IS PROJECTED TO REMAIN VERY HIGH AT 2.0-2.3 INCHES... WELL ABOVE SEASONAL NORMALS... AND MODELS SHOW SLIGHTLY BETTER POTENTIAL FOR INSTABILITY TUE AFTERNOON WITHIN PERSISTENT HIGH THETA-E ADVECTION IN THE LOW LEVELS. DESPITE THE WEAK WIND FIELD AND MARGINAL DPVA... WE SHOULD SEE DECENT UPPER DIVERGENCE OVER THE AREA IN THE LEFT EXIT REGION OF THE BROAD JET FROM THE GULF INTO THE TN VALLEY. WILL TREND POPS UP TO LIKELY OVER MUCH OF THE CWA BY AFTERNOON... WANING GRADUALLY IN THE EVENING/NIGHTTIME BUT STAYING AT 30-50%... WITH BETTER SHOWER CHANCES SHIFTING WNW INTO THE NW PIEDMONT AND FOOTHILLS WITH TIME. SLIGHTLY BETTER CAPE AND SHEAR ARE EXPECTED... STILL MARGINAL THOUGH... SO HAVE INCLUDED JUST A MENTION OF ISOLATED THUNDER IN THE AFTERNOON. HIGHS 75-83 AND LOWS 66-71... BOTH ABOVE NORMAL... WITH MOSTLY CLOUDY SKIES HOLDING FIRM. -GIH && .LONG TERM /WEDNESDAY THROUGH SUNDAY/... AS OF 327 AM MONDAY... UNCERTAINTY IN THE FORECAST IS ABOUT AS HIGH AS CAN BE ADVERTISED FROM MID WEEK INTO THE WEEKEND. THE OPERATIONAL MODELS CONTINUE TO SHOW PLENTY OF SPREAD AND EVEN THE ENSEMBLE MEANS ARE CONFLICTING ON THE PLACEMENT OF THE IMPORTANT WEATHER PRODUCING SYSTEMS. THE MAIN WEATHER HAZARDS SHOULD BE LIMITED TO A LOW END HEAVY RAIN THREAT... BUT SIGNIFICANT RAINFALL MAY BE MORE OF A HELP TO CURRENT DROUGHT STATUS THAN IT WOULD BE A THREAT FOR FLOODING. THE QPF MID TO LATE WEEK IS THE MAIN QUESTION AS ABOUT 30 PERCENT OF THE MODELS INDICATE THE HEAVIEST RAIN INLAND WITH OVERRUNNING RAINS AGAIN THU NIGHT INTO SATURDAY... WHICH 70 PERCENT OF THE MODELS SUPPORT THE HEAVY SWATH OF QPF ALONG OR JUST OFF THE MID-ATLANTIC COAST. ONE THING SEEMS TO BE MORE CERTAIN SHOULD BE THE COOLER TEMPERATURES AGAIN AS ANOTHER STRONG SURFACE HIGH IS EXPECTED TO BUILD SOUTH INTO NC/SC THURSDAY INTO THE WEEKEND. THIS OCCURS AS A TROUGH ALOFT AND LINGERING LOW LEVEL BOUNDARY CONTINUE TO BE FORECAST BY MOST MODELS TO BRING A CONTINUATION OF THE UNSETTLED PATTERN THAT BEGAN LATE LAST WEEK. A RETURN TO A PROLONGED NE FLOW... CONSIDERABLE CLOUDINESS... AND POSSIBLY SIGNIFICANT RAIN IS EXPECTED THU-SAT. && .AVIATION /12Z MONDAY THROUGH FRIDAY/... AS OF 640 AM MONDAY... MOIST AND DEEP LOW LEVEL FLOW FROM THE EAST WILL CONTINUE TO BRING MOSTLY ADVERSE AVIATION CONDITIONS TODAY... ESPECIALLY AT INT/GSO... WHERE IFR/LIFR CIGS AND MVFR/IFR VSBYS ARE LIKELY TO HOLD THROUGH 14Z... ALONG WITH PATCHY DRIZZLE. FARTHER EAST AT RDU/RWI/FAY... MVFR CIGS SHOULD HOLD THROUGH 14Z... ALTHOUGH A SHORT PERIOD OF IFR IS POSSIBLE. SOON AFTER 14Z... CIGS AT ALL LOCATIONS SHOULD SLOWLY BEGIN TO LIFT THROUGH THE MVFR CATEGORY... LASTING UNTIL AROUND 18Z OR 19Z WHEN SOME BREAKS IN THE CLOUDS ARE EXPECTED... ALTHOUGH ANY SCT/BKN CLOUDS ARE STILL LIKELY TO BE BASED AT 2500-3000 FT AGL. A TREND BACK TO MVFR TO IFR CIGS IS EXPECTED BY MID EVENING (AFTER 00Z TUE)... LASTING THROUGH TONIGHT... WITH POTENTIAL IFR/LIFR FOG FORMING OVERNIGHT. A FEW SHOWERS ARE POSSIBLE ESPECIALLY THIS AFTERNOON AND THESE COULD PRODUCE A PERIOD OF SUB-VFR VSBYS. LOOKING BEYOND 12Z TUE: IFR CONDITIONS ARE EXPECTED TO RULE THROUGH DAYBREAK TUE... ALTHOUGH RWI MAY STAY MVFR FOR MUCH OF THE NIGHT WITH PATCHY FOG. INT/GSO SHOULD STAY MVFR THROUGH TUE BUT RDU/RWI/FAY SHOULD LIFT TO MVFR THEN PERHAPS LOW-END VFR TUE AFTERNOON. IFR/LIFR CONDITIONS IN FOG ARE EXPECTED TO RETURN LATE TUE EVENING THROUGH DAYBREAK WED. VFR CONDITIONS THROUGH MIDDAY WED BUT SHOWERS/STORMS AHEAD OF A COLD FRONT MAY BRING SUB-VFR CONDITIONS WED/WED NIGHT. THIS FRONT WILL MOVE THROUGH WED NIGHT AND STALL TO OUR SE INTO FRI... POTENTIALLY BRINGING A RETURN TO PREDOMINANTLY POOR AVIATION CONDITIONS WITHIN AREAS OF RAIN/DRIZZLE. -GIH && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...HARTFIELD NEAR TERM...HARTFIELD SHORT TERM...HARTFIELD LONG TERM...BADGETT AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1008 AM EDT MON SEP 28 2015 .SYNOPSIS... HIGH PRESSURE CENTERED OFF THE NEW ENGLAND COAST WILL PUSH OUT TO SEA TODAY...WHILE MOISTURE INCREASES AND AN UPPER LEVEL DISTURBANCE FOCUSES SCATTERED SHOWERS ACROSS MAINLY THE WESTERN HALF OF PENNSYLVANIA. A COLD FRONT WILL PUSH SOUTH ACROSS PENNSYLVANIA LATE TUESDAY...THEN STALL OUT SOUTH OF THE STATE. TROPICAL MOISTURE WILL FOCUS ON THE FRONT AND BRING A SOAKING RAIN TO MUCH OF CENTRAL AND EASTERN PENNSYLVANIA TUESDAY NIGHT THROUGH WEDNESDAY NIGHT. UNSETTLED CONDITIONS WILL PREVAIL FOR THE REMAINDER OF THE WEEK...AS A SLOW MOVING COASTAL LOW AFFECTS PORTIONS OF THE MID ATLANTIC REGION LATE IN THE WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... SHEARING 5H TROF LIFTING OVER THE WESTERN PERIPHERY OF THE RETREATING OFFSHORE 5H RIDGE AND ASSOCIATED 850 MB CONVERGENCE ZONE COINCIDENT WITH 25-30KT JET AND PW POOLING TO 1.5" WILL CONTINUE TO FOCUS SHOWERS INTO THIS AFTERNOON ACROSS WESTERN AND CENTRAL PORTIONS. EARLIER HI RES HRRR WAS NOT HANDLING THIS FORCING AND SHOWERS ADEQUATELY AS IT PROPOGATES EASTWARD...BUT HAS NOW CAUGHT UP TO CURRENT RADAR TRENDS. BUMPED POPS AND QPF UPWARD FOR THE CENTRAL AND NORTH CENTRAL MOUNTAINS THROUGH THIS AFTERNOON AS A RESULT. MOST AREAS WILL SEE LESS THAN A TENTH OF AN INCH OVER THE CENTRAL MOUNTAINS...WITH LOCALLY ONE TO TWO TENTHS TOTAL FROM THE LAUREL HIGHLANDS INTO THE WEST CENTRAL MOUNTAINS. THE SHOWERS WILL SLOWLY PROPOGATE EASTWARD THROUGHOUT THE AFTERNOON AS THE UPPER RIDGE IS DISPLACED EASTWARD. THE MOIST SERLY LLVL FLOW AND OROGRAPHIC LIFT WILL KEEP CLOUDY SKIES OVER ALL OF CENTRAL PA. HIGHS WILL RANGE FROM THE MID TO UPPER 60S OVR THE ALLEGHENY PLATEAU TO THE U70S SOUTHEAST. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/... WEAK FORCING...AS INFERRED BY MDL 500-300MB QVEC DIV FIELDS...SHOULD RESULT IN LITTLE IF ANY RAIN TONIGHT...DESPITE POSITIVE PWAT ANOMALIES OF 2SD PER LATEST GEFS. CLOUD COVER AND SURGING DWPT WILL TRANSLATE TO A MILD NIGHT FOR LATE SEPT...WITH MINS BTWN 60-65F. A MORE SIG SHORTWAVE WILL PUSH SE INTO THE GRT LKS ON TUESDAY...PUSHING A COLD FRONT TOWARD NW PA BY LATE IN THE DAY. DEEP SOUTHERLY FLOW AND SURGING PWATS...COMBINED W/APPROACH OF SHORTWAVE...SHOULD PROMOTE NUMEROUS SHRA/TSRA...ESP DURING THE PM HOURS. BASED ON LATEST ENSEMBLE OUTPUT...HAVE RAISED POPS ACROSS THE BOARD. DESPITE OVERCAST SKIES...TEMPS SHOULD AGAIN BE SEVERAL DEG ABV AVERAGE WITH MID SUMMER-LIKE DWPTS MAKING IT FEEL EVEN WARMER. && .LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/... INCREASING CONFIDENCE IN SIG RAINFALL ACROSS PARTS OF CENTRAL PA TUES NIGHT/WED...AS SLOW-MOVING COLD FRONT INTERACTS WITH PLUME OF TROPICAL MOISTURE. PWATS NR 3SD ABV NORMAL...COMBINED WITH MDL INSTABILITY AND SLOW MOVING FRONT SUPPORT THE IDEA OF FAIRLY WIDESPREAD 1+ INCH AMTS...WITH MUCH HIGHER LOCALIZED AMTS. GIVEN THE RECENT DRYNESS...WIDESPREAD FLOODING NOT A CONCERN. HOWEVER...WILL MENTION POTENTIAL OF LOCALIZED FLOODING IN THE HWO. CONFIDENCE IN LINGERING WET WX APPEARS TO BE INCREASING ACROSS CENTRAL PA LATE THIS WEEK...AS ALL MDLS HAVE CONVERGED ON IDEA OF A CUT OFF LOW FORMING OVR THE OHIO VALLEY WITH ASSOC SFC LOW CRAWLING UP THE MID ATL COAST. HAVE INCREASED POPS IN THE THU-SAT TIME FRAME...WITH THE HIGHEST POPS ACROSS THE SOUTHEAST COUNTIES. AFTER A VERY MILD MON-TUE...NORTHERLY FLOW/LOW LVL CAA IN WAKE OF COLD FRONT...COMBINED WITH POSSIBLE RAIN...SHOULD TRANSLATE TO TEMPS BLW CLIMO LATE NEXT WEEK...ESP DURING THE DAYTIME. && .AVIATION /14Z MONDAY THROUGH FRIDAY/... WIDESPREAD IFR/AREAS MVFR COVERING CENTRAL PA THIS MORNING INTO THIS AFTERNOON AS LOW LEVEL MOISTURE IN THE LOWEST 5KFT AGL CONTINUES TO INCREASE ON SOUTHERLY FLOW. THESE RESTRICTIONS WILL REMAIN IN PLACE THE MAJORITY OF THE DAY...ESP WEST WHERE A RELATIVELY SHORT PERIOD OF MVFR CIGS POSS IN THE AFTERNOON. THE LOWER SUSQ WILL IMPROVE MORE DRAMATICALLY...LIKELY REACHING VFR FOR A GOOD PORTION OF THE AFTERNOON. NUMEROUS -SHRA WILL AFFECT PRIMARILY THE WESTERN HALF OF CWA. SURFACE WINDS WILL BE FROM THE EAST TO SOUTHEAST AT SPEEDS OF GENERALLY 5-10MPH. LOW CIGS REDEVELOP AREAWIDE OVERNIGHT...WITH WIDESPREAD IFR REDUCTIONS. LOWER CIGS CONTINUE INTO TUE...WITH AREA OF SHOWERS MOVING IN. OUTLOOK... TUE...LOW CIGS/SHOWERS LIKELY...ESP NW HALF. TUE NIGHT...LOW CIGS/SCT SHOWERS. WED...LOW CIGS NW MTNS EARLY. CHC SHOWERS SOUTH. THU...NO SIG WX. FRI...CHC OF SHOWERS. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...FITZGERALD NEAR TERM...DEVOIR/FITZGERALD SHORT TERM...FITZGERALD LONG TERM...FITZGERALD AVIATION...DEVOIR/RXR
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
624 AM CDT MON SEP 28 2015 .AVIATION UPDATE... 12Z TAFS...OVERCAST VFR CONDITIONS ARE EXPECTED TODAY WITH SCT -SHRA DEVELOPING OVER THE AREA. A SURGE OF TROPICAL MOISTURE WILL BRING WIDESPREAD SHOWERS TONIGHT INTO TUESDAY. CONDITIONS WILL DETERIORATE TONIGHT WITH MAINLY MVFR BY 06Z AND MAINLY IFR CIGS/VSBYS BY 10Z. 13 && .PREV DISCUSSION... /ISSUED 320 AM CDT MON SEP 28 2015/ SHORT TERM...IT WAS A MOSTLY CLOUDY AND MUGGY NIGHT ACROSS MID TN...WITH A FEW LIGHT SHOWERS OVER THE PLATEAU. WX FEATURES WE ARE WATCHING FOR THIS FORECAST INCLUDE AN UPPER LEVEL LOW PRESSURE SYSTEM ALONG THE TX GULF COAST...AND A TROPICAL LOW OVER THE GULF OF MEXICO. SATELLITE AND RADAR LOOPS SHOWED DEEP TROPICAL MOISTURE AND SHOWERS STREAMING NORTHWARD FROM THE GULF. FOR TODAY...CLOUDS WILL THICKEN AND THE COVERAGE OF SHOWERS WILL INCREASE THROUGH THE DAY...ESPECIALLY FOR OUR SOUTHERN COUNTIES. HIGHS WILL RANGE IN THE UPPER 70S TO LOWER 80S WITH MUGGY DEW POINTS IN THE 60S. FOR TONIGHT THROUGH TUESDAY...A SURGE OF DEEP TROPICAL MOISTURE WILL PUSH INTO TN. PRECIPITABLE WATER VALUES WILL REACH AROUND 2 INCHES BY TUESDAY MORNING. AT THE SAME TIME...IMPULSES WILL LIFT NORTHWARD AHEAD OF THE TX UPPER LEVEL LOW...AND A DISTURBANCE WILL APPROACH FROM THE NORTHWEST. THE TROPICAL LOW WILL TRACK ACROSS NORTH FL TOWARD THE CAROLINA COAST...BUT MOISTURE WITH THIS SYSTEM WILL SPREAD WELL NWWD TO THE TN VALLEY. THESE INGREDIENTS WILL LEAD TO WIDESPREAD SHOWERS AND A FEW THUNDERSTORMS LATE TONIGHT THROUGH TUESDAY. AVERAGE RAINFALL AMOUNTS THROUGH TUESDAY ARE EXPECTED TO RANGE FROM AROUND ONE HALF INCH OVER OUR NORTHWEST COUNTIES TO MORE THAN 1 INCH OVER THE SOUTH. LOCALLY GREATER AMOUNTS WITH HEAVY DOWNPOURS ARE LIKELY OVER THE SOUTH AND PLATEAU AS WELL. UPPER LEVEL WINDS WILL TURN NORTHWEST TUESDAY NIGHT INTO WEDNESDAY WITH A COLD FRONT PASSAGE. THE COVERAGE AND INTENSITY OF SHOWERS WILL DECREASE. LONG TERM...COOLER AIR WILL MOVE IN FOR THE EXTENDED FORECAST. OVERNIGHT LOWS WILL BE DIPPING INTO THE 50S WITH HIGHS MAINLY IN THE UPPER 60S TO LOWER 70S...WHICH WOULD BE JUST A COUPLE OF DEGREES COOLER THAN NORMAL. MODELS SUGGEST AN UPPER TROUGH WILL LINGER...POSSIBLY KEEPING SOME SHOWERS AROUND FOR THE UPPER CUMBERLAND REGION LATE WEEK THROUGH THE WEEKEND. ANOTHER SYSTEM MAY BRING SCATTERED SHOWERS ACROSS THE AREA INTO EARLY NEXT WEEK...BUT CONFIDENCE IS LOW REGARDING THE DETAILS. 13 PREV DISCUSSION... /ISSUED 1142 PM CDT SUN SEP 27 2015/ AVIATION UPDATE... RAIN ACTIVITY HAS BEEN UNDERWHELMING THIS EVENING AND HRRR DOES NOT PAINT A WET PICTURE FOR THE REST OF THE OVERNIGHT HOURS. TOOK OUT VCSH AT ALL THREE TERMINALS UNTIL MORNING WHERE GUIDANCE BUMPS POPS SLIGHTLY. BR WILL BE AN ISSUE AT CKV AND CSV OVERNIGHT. THE MORE SIGNIFICANT OMEGA AND RAIN CHANCES WILL HOLD OFF UNTIL AFTER THE END OF THE TAF PERIOD. WINDS WILL BE E/SE UNDER 5 KTS DURING THE TAF PERIOD. && .PRELIMINARY POINT TEMPS/POPS... NASHVILLE 81 66 78 65 / 40 80 90 50 CLARKSVILLE 81 66 78 63 / 30 60 80 40 CROSSVILLE 77 64 74 63 / 30 80 100 60 COLUMBIA 80 65 79 65 / 40 80 90 50 LAWRENCEBURG 79 65 79 65 / 50 80 90 50 WAVERLY 81 65 79 64 / 30 70 80 40 && .OHX WATCHES/WARNINGS/ADVISORIES...NONE. && $$
AREA FORECAST DISCUSSION
NWS PUEBLO CO
335 PM MDT MON SEP 28 2015 .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 335 PM MDT MON SEP 28 2015 ...COOLER WEATHER MOVING INTO THE REGION... CURRENTLY... COOL FRONT WAS MOVING SLOWLY SOUTHWARD ACROSS THE PLAINS EARLY THIS AFTERNOON. WELL DEFINED BOUNDARY WAS NOTED ON KPUX AT 3 PM RUNNING NEARLY E-W FROM JUST N OF KPUB TO JUST N OF EADS. NORTH OF THIS BOUNDARY WINDS WERE GENERALLY FROM THE NORTH WHILE SOUTH OF THIS BOUNDARY EASTERLY WINDS WERE NOTED. A LINE OF WEAK CUMULUS WERE NOTED WITH THE BOUNDARY ACROSS THE PLAINS. A WEAK SHORT WAVE WAS NOTED ACROSS W WY/NW CO THIS AFTERNOON AND IT IS THIS WAVE THAT WILL BRING THE FRONT DOWN THE PLAINS LATER TODAY AND INTO THIS EVENING. REST OF TODAY INTO TONIGHT... WE WILL LIKELY SEE SOME SHOWERS DEVELOP OVER THE PLAINS THIS AFTERNOON INTO THIS EVENING. MODELS VARY ON INTENSITY AND LOCATION...BUT THERES A GOOD CHANCE WE WILL SEE SOME ACTIVITY...WITH THE BEST CHANCES BEING GENERALLY N OF HIGHWAY 50. HRRR IS THE MOST AGGRESSIVE OF THE GUIDANCE WITH A CLUSTER OF WEAK STORMS FORMING UP IN EL PASO COUNTY AND THEN DROPPING EAST-SOUTHEAST ACROSS THE PLAINS. HRRR HAS BEEN HANGING ONTO THIS SOLUTION FOR SEVERAL RUNS...BUT BELIEVE IT MAY BE OVERDONE AS COMPARED TO OTHER GUIDANCE. AS FOR CLOUDS LATER TONIGHT...EXPECT WE WILL SEE A BROKEN DECK DEVELOP BUT BELIEVE ANY CIG WILL MAINLY BE A MID LVL DECK AS PER SOUNDINGS. CANT RULE OUT SOME LOWER CLOUDS UP IN N EL PASO COUNTY AND MAYBE OVER THE FAR E PLAINS. WE WILL LIKELY SEE SOME GUSTY NE WINDS DEVELOP SOON OVER THE EL PASO/PUEBLO COUNTY REGION AND LAST INTO EARLY EVENING AS THE FRONT SURGES SOUTH. TOMORROW... MOS PRODUCTS SHOW RATHER HIGH POPS TOMORROW ACROSS THE REGION...ESPECIALLY ALONG THE MTNS/PLAINS INTERFACE. GIVEN THE UPSLOPE FLOW AND FORCING...PRECIP WILL OCCUR BUT I AM A BIT HESITANT ON GOING AS HIGH AS MOS GUIDANCE. FOR NOW PAINTED THE GREATER I-25 CORRIDOR REGION IN SCATTERED POPS WITH MORE ISOLATED POPS ACROSS THE REST OF THE REGION. AS THE AFTERNOON PROGRESSES...BETTER CHANCE OF PRECIP WILL BE ALONG THE RATON MESA REGION AS FOR TIMING...SHOWERS WILL BE POSSIBLE AS EARLY AS LATE MORNING ACROSS THE PIKES PEAK REGION...AND THE AREA OF PRECIP WILL INCREASE AS IT MOVES SOUTH-SOUTHEAST DOWN THE S MTN RANGE. THE BIG NEWS TOMORROW WILL BE THE SEASONABLE TEMPERATURES THAT WILL FINALLY RETURN TO THE AREA...AS HIGHS WILL ONLY BE IN THE 60S ACROSS N EL PASO COUNTY AND 70S ACROSS THE REST OF THE PLAINS. VALLEYS WILL REMAIN WARMER THAN NORMAL AS COOLER AIR WILL NOT GET INTO THE LARGER VALLEYS. WILL LIKELY SEE QUITE A BIT OF CLOUDINESS OVER THE REGION TOMORROW. /HODANISH .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 335 PM MDT MON SEP 28 2015 .TUESDAY NIGHT...CONVECTION ON THE PLAINS WILL MOVE INTO NEW MEXICO. MODELS TRY TO DEVELOP SOME PRECIPITATION OVER WESTERN KANSAS OVERNIGHT WITH A WEAK DISTURBANCE PASSING TO OUR NORTH. BELIEVE PRECIPITATION WILL STAY TO THE NORTHEAST OF THE CWA AND HAVE ONLY SILENT POPS AFTER MIDNIGHT. .WEDNESDAY...UPSLOPE FLOW WILL PERSIST OVER THE PLAINS WITH DEW POINTS FORECAST TO BE IN THE LOWER 50S. SPC DAY 3 OUTLOOK HAS A MARGINAL RISK FOR PORTIONS OF THE SOUTHEAST PLAINS. MODELS HAVE CAPES AROUND 1000 J/KG. WITH FORECAST 500MB WINDS AROUND 30 KNOTS...THERE WILL BE ENOUGH SHEAR FOR STRONGER STORMS. SHORTWAVE APPEARS TO BE LACKING WHICH CAN HINDER THE DEVELOPMENT OF CONVECTION...GIVEN THE WEAKER AUTUMN SOLAR HEATING. HAVE SOME ISOLATED POPS IN THE GRIDS FOR THE POTENTIAL FOR A FEW STRONGER STORMS TO DEVELOP. .THURSDAY...UPPER RIDGE MOVES OVER THE REGION FOR A DRY AND WARM DAY. .FRIDAY THROUGH MONDAY...MODELS AND ENSEMBLES HAVE A SHORTWAVE MOVING OVER THE REGION FRIDAY INTO SATURDAY. WITH LOW LEVEL UPSLOPE ON THE PLAINS...THERE IS THE POTENTIAL FOR STRATIFORM PRECIPITATION TO DEVELOP OVER THE PLAINS ON FRIDAY INTO FRIDAY NIGHT. BEST FORCING WILL MOSTLY BE OVER THE NORTHERN HALF OF THE STATE. KEPT POPS ONLY IN THE SCATTERED CATEGORY FOR NOW AS AGREEMENT AMONG THE MODELS ON THE SPECIFIC DETAILS ARE LOW. THE MODEL DIFFERENCE BECOME MORE PRONOUNCED STARTING SATURDAY. EC AND CANADIAN HAVE THE LEADING SHORTWAVE MOVE EAST OF THE REGION BY SATURDAY. A MUCH STRONGER DISTURBANCE MOVES INTO THE PACIFIC NORTHWEST SATURDAY...THEN PROGRESSES INTO THE GREAT BASIN BY MONDAY. THIS IS A WARMER SOLUTION WITH MOISTURE FROM HURRICANE MARTY MOVING INTO THE REGION. THE GFS LACKS THE SECOND SHORTWAVE AND IT HAS AN UPPER LOW STALLING OVER COLORADO. THIS WOULD PROVIDE A MUCH COOLER AND WETTER SOLUTION. WPC SOLUTION SEEMS TO BE THE BLEND OF THE TWO AND PREDICTABILITY IS BELOW AVERAGE. CR EXTENDED GRIDS ARE A DECENT COMPROMISE OF THE TWO SOLUTIONS AND ONLY TWEAKED THE GRIDS FOR CONSISTENCY. WITH A TROUGH NEARBY...THIS WEEKEND COULD BE COOLER WITH MORE AUTUMN LIKE TEMPERATURES. --PGW-- --PGW-- && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING) ISSUED AT 335 PM MDT MON SEP 28 2015 OVERALL...VFR CONDITIONS EXPECTED NEXT 24H AT ALL 3 TAF SITES...KPUB...KALS AND KCOS. A COOL FRONT WAS MOVING DOWN THE PLAINS THIS AFTERNOON AND GUSTY NORTH-NORTHEAST WINDS WILL BE LIKELY LATER THIS AFTERNOON AND EARLY EVENING OVER KCOS AND POSSIBLY KPUB. A FEW SHOWERS MAY BE POSSIBLE...ESPECIALLY OVER KCOS THIS AFTERNOON/EARLY EVENING. CIGS WILL LIKELY DEVELOP BUT SHOULD BE PREDOMINANTLY MID LVL. TOMORROW...SHOWERS WITH A FEW ISOLD TSRA ARE LIKELY AT KCOS AND POSSIBLY AT KPUB. SHOWERS WILL FORM RELATIVELY EARLY (LATE MORNING?) AND MOVE SOUTH-SOUTHEAST DOWN THE I-25 CORRIDOR REGION. BEST CHANCE OF PRECIP WILL BE ALONG THE MTNS/PLAINS INTERFACE. KALS WILL REMAIN DRY WITH LIGHT WINDS. && .PUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...HODANISH LONG TERM...PGW AVIATION...HODANISH
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
1231 PM EDT MON SEP 28 2015 .SYNOPSIS... HIGH PRESSURE EXTENDED FROM THE NORTHEASTERN STATES OUT OVER THE ATLANTIC EARLY THIS MORNING AND WEAK LOW PRESSURE WAS LOCATED OFF THE SOUTHEAST COAST. THE HIGH WILL CONTINUE TO MOVE FARTHER OUT TO SEA AND THE LOW SHOULD DRIFT NORTHWARD THROUGH TUESDAY NIGHT. A COLD FRONT IS FORECAST TO APPROACH FROM THE NORTHWEST AND IT SHOULD PASS THROUGH OUR REGION ON WEDNESDAY. THE BOUNDARY IS EXPECTED TO STALL OFF THE COAST FOR THURSDAY AND FRIDAY AS AREAS OF LOW PRESSURE MOVE NORTHWARD ALONG IT. ONE OF THE LOWS IS ANTICIPATED TO STRENGTHEN AS IT REACHES EASTERN CANADA OVER THE WEEKEND, PULLING THE FRONT FARTHER OUT TO SEA AND ALLOWING HIGH PRESSURE TO BEGIN BUILDING INTO OUR REGION. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... SURFACE HIGH PRESSURE RIDGE REMAINS ENTRENCHED ALONG THE APPALACHIANS. LOW LEVEL MOISTURE DUE TO THE CONTINUED ONSHORE FLOW AND A WEAKER PRESSURE GRADIENT HAS ALLOWED FOG TO DEVELOP THIS MORNING, ESPECIALLY CLOSER TO THE COAST. EXPECT THE FOG TO DISSIPATE BY LATE MORNING, WITH CONSIDERABLE CLOUDINESS FOR THE REMAINDER OF THE DAY. THERE IS GREATER MOISTURE IN THE COLUMN COMPARED TO YESTERDAY, BUT THERE IS NOT MUCH IN THE WAY OF LIFT, SO EXPECTING A DRY DAY. THE ONLY EXCEPTION WILL BE ALONG THE COAST WHERE THE NAM AND HRRR INDICATE SOME LIGHT RAIN SHOWERS MOVING ONSHORE. CURRENT RADAR AND SATELLITE TRENDS SUPPORT THIS, SO HAVE INSERTED A SLIGHT CHANCE OF RAIN SHOWERS INTO THE FORECAST ALONG THE COAST. ALSO MADE SOME ADJUSTMENTS TO REDUCE SKY COVER AND INCREASE MAX TEMPS A COUPLE DEGREES SOUTHEAST OF I-95. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 AM TUESDAY/... THE DRY AIR CONTINUES TO BE REPLACED BY EVEN MORE MOIST AIR OVERNIGHT TONIGHT AS THE HIGH PULLS FARTHER AWAY FROM THE AREA. WITH ADDITIONAL VORTICITY IMPULSES WITHIN THE SOUTHWEST FLOW ALOFT, RAIN CHANCES CONTINUE TO INCREASE OVERNIGHT. ADDITIONALLY, THERE COULD BE SOME FOG DEVELOP ONCE AGAIN, ESPECIALLY FOR HIGHER ELEVATIONS ACROSS NORTHEAST PENNSYLVANIA AND NORTHWEST NEW JERSEY. WE`VE INCLUDED FOG ONCE AGAIN IN THE GRIDS ACROSS THOSE AREAS WHERE VISIBILITIES MAY BE LOWER. OVERNIGHT LOWS ARE EXPECTED TO BE SEVERAL DEGREES ABOVE NORMAL, AS CLOUDS SHOULD PREVENT ANY RADIATIONAL COOLING. && .LONG TERM /TUESDAY THROUGH SUNDAY/... THE HIGH OFF THE COAST WILL CONTINUE TO LOSE ITS INFLUENCE OVER OUR REGION ON TUESDAY. WARM HUMID AIR IS ANTICIPATED TO SETTLE INTO OUR REGION WITH MAXIMUM TEMPERATURES EXPECTED TO BE MAINLY IN THE UPPER 70S AND LOWER 80S. THE POTENTIAL FOR RAIN SHOWERS WILL BE ON THE INCREASE THROUGH THE DAY, ESPECIALLY IN OUR COUNTIES IN EASTERN PENNSYLVANIA AS A COLD FRONT BEGINS TO APPROACH FROM THE NORTHWEST. THE MODEL GUIDANCE HAS BEEN TRENDING TOWARD A LESS PROGRESSIVE SOLUTION WITH THE COLD FRONT. IT NOW APPEARS AS THOUGH IT WILL PASS THROUGH OUR FORECAST AREA ON WEDNESDAY BEFORE STALLING OFF THE COAST FOR THURSDAY AND FRIDAY. PRECIPITABLE WATER VALUES ARE FORECAST TO REACH AND EXCEED 2 INCHES IN MOST OF OUR FORECAST AREA AHEAD OF THE COLD FRONT. AS A RESULT, WE WILL CONTINUE TO MENTION THE POTENTIAL FOR HEAVY RAINFALL. ALSO, WE HAVE INCLUDED A CHANCE OF THUNDERSTORMS AS THE LIFT WITH AND AHEAD OF THE FRONT SEEMS FAIRLY ROBUST. GENERAL RAINFALL AMOUNTS OF AN INCH OR TWO SEEM POSSIBLE FOR MUCH OF OUR REGION. BEING THAT ANTECEDENT CONDITIONS HAVE BEEN QUITE DRY, OUR THINKING IS THAT WE WILL SEE SOME LOCALIZED FLOODING IN AREAS OF POOR DRAINAGE BUT THE POSSIBILITY OF WIDESPREAD FLOODING IS LOW. CLOUDS AND A CHANCE OF LIGHT RAIN SHOULD LINGER DURING THE LATE WEEK PERIOD WITH THE FRONT STALLED OFF THE COAST. THE TIMING AND STRENGTH OF LOW PRESSURE WAVES MOVING ALONG THE BOUNDARY REMAINS QUITE UNCERTAIN AT THIS TIME, SO THE DETAILS OF THE FORECAST REMAIN LOW CONFIDENCE AT THIS POINT. WE WILL GO WITH THE IDEA OF A STRENGTHENING LOW FINALLY BEGINNING TO PULL THE FRONT FARTHER OFF THE COAST OVER THE WEEKEND. IT MAY ALLOW HIGH PRESSURE AND SOME CLEARING TO BEGIN WORKING INTO OUR REGION FROM THE WEST AT THAT TIME. DAYTIME TEMPERATURES SHOULD FALL BELOW NORMAL FOR THE LATE WEEK PERIOD INTO THE WEEKEND IN THE WAKE OF THE COLD FRONT. && .AVIATION /18Z MONDAY THROUGH SATURDAY/... THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY AND SURROUNDING AREAS. CEILINGS HAVE LOWERED TO IFR AT DAYBREAK. FOG HAS ALSO DEVELOPED, WITH THE LOWEST CEILINGS NEAR THE COAST, WHERE ACY HAS BEEN DOWN TO 1/4SM ATTMS. THE FOG SHOULD DIMINISH AROUND 15Z. HOWEVER, THE LOW CLOUDS ARE EXPECTED TO REMAIN ACROSS THE SITES THROUGH MID MORNING, THEN BEGIN LIFTING TO MVFR, THEN VFR BY THE AFTERNOON. AFTER A PERIOD OF VFR FOR THE AFTERNOON INTO THE EARLY EVENING, CIGS ARE EXPECTED TO LOWER BACK TO MVFR DURING THE EVENING HOURS, AND EVENTUALLY BACK TO IFR/LIFR OVERNIGHT. IN ADDITION, FOG MAY BE MORE EXTENSIVE TONIGHT AND TUESDAY MORNING. NORTHEASTERLY WINDS EARLY IN THE DAY ARE EXPECTED TO BECOME MORE EASTERLY, THEN SOUTHEASTERLY LATER IN THE DAY AND CONTINUE INTO THE OVERNIGHT HOURS. WIND SPEEDS ARE EXPECTED TO BE 5-10 KNOTS THROUGH THE PERIOD. OUTLOOK... TUESDAY...IFR AND MVFR CONDITIONS IN THE MORNING GRADUALLY IMPROVING TO MAINLY VFR FOR THE AFTERNOON. A CHANCE OF SHOWERS. TUESDAY NIGHT AND WEDNESDAY...RAIN DEVELOPING AND BECOMING HEAVY AT TIMES ALONG WITH A CHANCE OF THUNDERSTORMS. MVFR AND IFR CONDITIONS ARE LIKELY. WEDNESDAY NIGHT...MAINLY VFR WITH A CHANCE OF RAIN. THURSDAY...MAINLY VFR. A CHANCE OF RAIN, MOSTLY TO THE SOUTH AND SOUTHEAST OF KPHL. THURSDAY NIGHT...MAINLY VFR. FRIDAY...MAINLY VFR WITH A CHANCE OF RAIN. && .MARINE... AS THE FLOW RELAXES ACROSS THE AREA, WINDS HAVE DROPPED BELOW 25 KNOTS. HOWEVER, SEAS REMAIN ELEVATED ACROSS THE WATERS. THEREFORE WE WILL KEEP THE SMALL CRAFT ADVISORY, BUT HAVE CONVERTED IT TO SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS. OUTLOOK... TUESDAY AND TUESDAY NIGHT...A SMALL CRAFT ADVISORY REMAINS IN EFFECT FOR OUR OCEAN WATERS WITH WAVE HEIGHTS EXPECTED TO RANGE FROM 4 TO 6 FEET. WEDNESDAY THROUGH FRIDAY...SMALL CRAFT ADVISORY CONDITIONS WILL LIKELY CONTINUE ON OUR OCEAN WATERS AND ON DELAWARE BAY DUE TO AN INCREASING NORTHEAST WIND. WAVE HEIGHTS ON OUR OCEAN WATERS ARE FORECAST TO BUILD TO 6 TO 12 FEET. GALE FORCE GUSTS ARE POSSIBLE ON OUR OCEAN WATERS FROM WEDNESDAY NIGHT INTO FRIDAY. && .TIDES/COASTAL FLOODING... TIDES WILL CONTINUE TO RUN HIGH TODAY INTO TONIGHT AND APPROACH THE MINOR FLOOD LEVEL. HOWEVER, WE DO NOT EXPECT THE LEVELS TO REACH CRITERIA REQUIRED TO ISSUE A FLOOD ADVISORY. A STRONG NORTHEASTERLY SURFACE FLOW IS FORECAST TO REDEVELOP DURING THE SECOND HALF OF THE WORK WEEK. AS A RESULT, WE MAY SEE ANOTHER ROUND OF MINOR TIDAL FLOODING AT THAT TIME. ALSO, BEACH EROSION IS POSSIBLE. && .RIP CURRENTS... THE COMBINATION OF HIGH WAVES, MODERATE PERIOD SWELL, AND A STEADY EASTERLY FLOW WILL CONTINUE TO CREATE A HIGH RISK FOR THE DEVELOPMENT OF DANGEROUS RIP CURRENTS THROUGH THIS EVENING. AFTER TODAY, THERE MAY BE A WEAK ENOUGH FLOW ON TUESDAY AND WEDNESDAY TO HAVE THE DANGEROUS RIP CURRENT RISK LESS THAN HIGH. THE SURF ZONE FORECAST ENDS WITH THE MORNING FORECAST ON WEDNESDAY THE 30TH. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...NONE. NJ...HIGH RIP CURRENT RISK UNTIL 8 PM EDT THIS EVENING FOR NJZ014- 024>026. DE...HIGH RIP CURRENT RISK UNTIL 8 PM EDT THIS EVENING FOR DEZ004. MD...NONE. MARINE...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 6 AM EDT WEDNESDAY FOR ANZ450>455. && $$ SYNOPSIS...IOVINO NEAR TERM...FRANCK/ROBERTSON SHORT TERM...ROBERTSON LONG TERM...IOVINO AVIATION...FRANCK/IOVINO/ROBERTSON MARINE...FRANCK/IOVINO/ROBERTSON TIDES/COASTAL FLOODING... RIP CURRENTS...
AREA FORECAST DISCUSSION
NWS LINCOLN IL
603 PM CDT MON SEP 28 2015 .SHORT TERM...(TONIGHT) ISSUED AT 252 PM CDT MON SEP 28 2015 Original shield of lower clouds has been contracting throughout the day, and was basically limited to areas from Peoria to Chicago this afternoon. Remainder of the CWA has seen clouds more of a diurnal nature, which has allowed enough sunshine to get temperatures into the lower 80s. So far the showers have remained extremely isolated. Precipitation threat for the forecast area tonight will be coming from a couple different directions. Across the southeast CWA, some upper level energy will continue to surge northward up the Mississippi River as the upper low over east Texas lifts northeast and starts to open up. Showers should remain isolated this evening, before rain chances start to ramp up late night as the energy gets closer. Could be a rumble or two of thunder in the far southeast late tonight, as the RAP shows lifted index values falling to near zero, but chance is too small at the moment to include in the forecast. Across the northwest CWA, the main player will be the cold front which currently is pushing through northwest Iowa. Arrival of the frontal boundary will be after 3 AM, and most of the rain will be post-frontal, so will only carry some slight 20-30% PoP`s northwest of the Illinois River late tonight. .LONG TERM...(Tuesday THROUGH Monday) ISSUED AT 252 PM CDT MON SEP 28 2015 A cold front will cross from near I-72 to start the day Tuesday to near the southern tip of Illinois by evening. At the same time, low pressure over the south central states will drift toward the southeastern U.S., helping to combine enough moisture, lift, and instability into mainly the southern half of Illinois for showers and isolated thunderstorms. As a result...keeping chances for showers/isolated thunder south of I-72 for Tuesday...with chances of showers diminishing to the north through the day. Highs will feature a strong gradient across central IL, ranging from the upper 60s in Galesburg to near 80 in Lawrenceville as cooler and drier air moves in behind the front. Dewpoints in the low to mid 60s to start the day to slip into the low to mid 50s behind the front over northern counties Tue afternoon. Breezy north-northeast winds behind the front will increase...reaching 10-15 mph with gusts into the 20 mph range. Fairly persistent high pressure will settle into the Great Lakes Region for the remainder of the work week...promoting an extended period of breezy northeast winds and mostly sunny skies. Highs will be in the upper 60s and low 70s through Friday with lows mainly in 40s. There remains fairly poor model agreement over the weekend into early next week...with a weak trough passing through the region in the GFS...but a building ridge into the Plains and upper Midwest in the ECMWF. Neither would have a good chance for precipitation and forecast is therefore dry. Both would feature lighter winds. Temperatures likely will feature minimal trend through the weekend and kept highs in the 60s and lows mid-upper 40s. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z Tuesday EVENING) ISSUED AT 603 PM CDT MON SEP 28 2015 Lots of mid clouds around 8kft still over the area, but based on observation trends and satellite loops, believe the lower mid clouds will dissipate quickly this evening and leave higher mid clouds or high clouds over the area remainder of the night. So will go with mid clouds around 12-15kft for the night with light and variable winds. Then tomorrow, after the front has moved through, scattered showers will be possible at all sites and winds will increase out of the north-northeast...behind the front. With light pcpn and vis decreasing, expecting MVFR cigs below 3kft at all sites during the day tomorrow. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...Geelhart LONG TERM...Onton AVIATION...Auten
AREA FORECAST DISCUSSION
NWS LINCOLN IL
252 PM CDT MON SEP 28 2015 .SHORT TERM...(TONIGHT) ISSUED AT 252 PM CDT MON SEP 28 2015 Original shield of lower clouds has been contracting throughout the day, and was basically limited to areas from Peoria to Chicago this afternoon. Remainder of the CWA has seen clouds more of a diurnal nature, which has allowed enough sunshine to get temperatures into the lower 80s. So far the showers have remained extremely isolated. Precipitation threat for the forecast area tonight will be coming from a couple different directions. Across the southeast CWA, some upper level energy will continue to surge northward up the Mississippi River as the upper low over east Texas lifts northeast and starts to open up. Showers should remain isolated this evening, before rain chances start to ramp up late night as the energy gets closer. Could be a rumble or two of thunder in the far southeast late tonight, as the RAP shows lifted index values falling to near zero, but chance is too small at the moment to include in the forecast. Across the northwest CWA, the main player will be the cold front which currently is pushing through northwest Iowa. Arrival of the frontal boundary will be after 3 AM, and most of the rain will be post-frontal, so will only carry some slight 20-30% PoP`s northwest of the Illinois River late tonight. && .LONG TERM...(Tuesday THROUGH Monday) ISSUED AT 252 PM CDT MON SEP 28 2015 A cold front will cross from near I-72 to start the day Tuesday to near the southern tip of Illinois by evening. At the same time, low pressure over the south central states will drift toward the southeastern U.S., helping to combine enough moisture, lift, and instability into mainly the southern half of Illinois for showers and isolated thunderstorms. As a result...keeping chances for showers/isolated thunder south of I-72 for Tuesday...with chances of showers diminishing to the north through the day. Highs will feature a strong gradient across central IL, ranging from the upper 60s in Galesburg to near 80 in Lawrenceville as cooler and drier air moves in behind the front. Dewpoints in the low to mid 60s to start the day to slip into the low to mid 50s behind the front over northern counties Tue afternoon. Breezy north-northeast winds behind the front will increase...reaching 10-15 mph with gusts into the 20 mph range. Fairly persistent high pressure will settle into the Great Lakes Region for the remainder of the work week...promoting an extended period of breezy northeast winds and mostly sunny skies. Highs will be in the upper 60s and low 70s through Friday with lows mainly in 40s. There remains fairly poor model agreement over the weekend into early next week...with a weak trough passing through the region in the GFS...but a building ridge into the Plains and upper Midwest in the ECMWF. Neither would have a good chance for precipitation and forecast is therefore dry. Both would feature lighter winds. Temperatures likely will feature minimal trend through the weekend and kept highs in the 60s and lows mid-upper 40s. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z Tuesday AFTERNOON) ISSUED AT 1225 PM CDT MON SEP 28 2015 Still a bit of MVFR conditions lingering around KBMI/KPIA, but this area continues to contract and ceilings will lift over the next couple hours. Main concern will be in the period after 10Z, when a cold front arrives from the northwest. Ceilings expected to fall below 3,000 feet with the arrival of the front, and remain that way the remainder of the forecast period. A few showers may precede the front, but most will be after its passage. Winds expected to shift to the north-northeast and increase to near 10 knots Tuesday morning behind the front. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...Geelhart LONG TERM...Onton AVIATION...Geelhart
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
117 PM CDT MON SEP 28 2015 .AVIATION... CIGS CONTINUE TO LIFT ACROSS THE REGION THIS AFTERNOON...AND MOST SITES ARE NOW IN THE VFR FLIGHT CATEGORY. THIS IS EXPECTED TO CONTINUE THROUGH THE DAY AND INTO THE OVERNIGHT HOURS...BEFORE MORE STRATUS DEVELOPS AFTER 06Z. WE MAY SEE SOME IMPROVEMENT FOR THOSE SITES THAT DO SEE STRATUS PRIOR TO THE END OF THE PD...BUT CIGS WILL MOST LIKELY HANG IN THROUGH 18Z TUESDAY. ADDITIONALLY...UPPER LOW PRESSURE SYSTEM ALONG THE GULF COAST WILL KEEP THE POSSIBILITY OF FOR ISOLD TO SCT SHWRS IN FOR OUR TERMINALS THROUGH MOST OF THE PD. OTHERWISE...NELY WINDS 5-10 KTS ARE EXPECTED THROUGH THE PD. /12/ && .PREV DISCUSSION... /ISSUED 1144 AM CDT MON SEP 28 2015/ UPDATE... ADJUST POPS AND WEATHER FOR THE AFTERNOON...EVENING AND OVERNIGHT. DISCUSSION... VERY NICE AND COASTALLY HUMID WITH MID TO UPPER 70S. OUR SKIES ARE MOSTLY CLOUDY TO CLOUDY WITH OUR RADAR FAIRLY QUIET AND GETTING QUIETER. THE OCCASIONALLY CONVERGENT FORCING REMAINS GOOD FOR SOME DEVELOPMENT TO UNFOLD WITH HEATING OF LOW TO MID 80S. HOWEVER...OVERNIGHT MAY TURN OUT TO BE EVEN MORE PRODUCTIVE THAN MODELED AT THIS TIME FOR THE EAST. SOME NEW 12Z DATA IS ENCOURAGING ON HRRR AND NAM. AT ANY RATE THIS SYSTEM IS OCCLUDED AND SURROUNDING ITSELF WITH DRY AIR...CUT OFF NOW FROM THE RICH TROPICAL CONNECTION OF YESTERDAY. RAINFALL AMOUNTS WILL BE TOO LIGHT FOR MOST EVERYONE...BUT WITH LUCKY FEW POSSIBLY SEEING AN INCH OR THREE. IN THE WAKE OF THE SYSTEM THE UPPER PATTERN WILL FALL ALOFT HEIGHT WISE AT LEAST COOLING THE 90 DEGREE HEAT OF LATE. A ZONAL PATTERN WILL ESTABLISH BY THE WEEKEND WITH ANOTHER SLIGHT CHANCE FOR SOME PRECIP IN NEXT MONTHS BUCKET. /24/ && .PRELIMINARY POINT TEMPS/POPS... SHV 70 86 69 88 / 30 40 20 10 MLU 69 85 68 87 / 50 40 20 20 DEQ 66 85 65 87 / 20 30 20 0 TXK 68 84 67 86 / 30 40 20 0 ELD 67 84 66 85 / 40 40 20 10 TYR 69 87 69 89 / 20 30 20 0 GGG 68 86 68 89 / 30 40 20 10 LFK 67 85 68 89 / 30 40 20 10 && .SHV WATCHES/WARNINGS/ADVISORIES... AR...NONE. LA...NONE. OK...NONE. TX...NONE. && $$ 12
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
1144 AM CDT MON SEP 28 2015 .UPDATE... ADJUST POPS AND WEATHER FOR THE AFTERNOON...EVENING AND OVERNIGHT. && .DISCUSSION... VERY NICE AND COASTALLY HUMID WITH MID TO UPPER 70S. OUR SKIES ARE MOSTLY CLOUDY TO CLOUDY WITH OUR RADAR FAIRLY QUIET AND GETTING QUIETER. THE OCCASIONALLY CONVERGENT FORCING REMAINS GOOD FOR SOME DEVELOPMENT TO UNFOLD WITH HEATING OF LOW TO MID 80S. HOWEVER...OVERNIGHT MAY TURN OUT TO BE EVEN MORE PRODUCTIVE THAN MODELED AT THIS TIME FOR THE EAST. SOME NEW 12Z DATA IS ENCOURAGING ON HRRR AND NAM. AT ANY RATE THIS SYSTEM IS OCCLUDED AND SURROUNDING ITSELF WITH DRY AIR...CUT OFF NOW FROM THE RICH TROPICAL CONNECTION OF YESTERDAY. RAINFALL AMOUNTS WILL BE TOO LIGHT FOR MOST EVERYONE...BUT WITH LUCKY FEW POSSIBLY SEEING AN INCH OR THREE. IN THE WAKE OF THE SYSTEM THE UPPER PATTERN WILL FALL ALOFT HEIGHT WISE AT LEAST COOLING THE 90 DEGREE HEAT OF LATE. A ZONAL PATTERN WILL ESTABLISH BY THE WEEKEND WITH ANOTHER SLIGHT CHANCE FOR SOME PRECIP IN NEXT MONTHS BUCKET. /24/ && .PREV DISCUSSION... /ISSUED 634 AM CDT MON SEP 28 2015/ AVIATION... UPPER-LEVEL DISTURBANCE TO ALLOW FOR VCTS CONDITIONS ACROSS AREA TERMINALS TODAY. CONVECTION TO DIMINISH AFTER 29/00Z. MVR/IFR CEILINGS AND VISIBILITES POSSIBLE ACROSS MOST TERMINAL SITES AFTER 29/06Z. OTHERWISE...LIGHT NORTHEAST WINDS TO PREVAIL THROUGH THE TERMINAL FORECAST PERIOD. /05/ && .PREV DISCUSSION... /ISSUED 421 AM CDT MON SEP 28 2015/ .DISCUSSION... CUTOFF UPPER TROUGH IS CENTERED OVER THE TX COAST JUST SW OF GALVESTON WHILE A SFC LOW IS LOCATED JUST TO THE EAST OF THE UPPER TROUGH OVER THE NW GULF OF MEXICO. SHWRS/TSTMS MOVING CYCLONICALLY AROUND THE TROUGH ARE GRADUALLY SPREADING NORTH INTO EAST TEXAS AND THE TOLEDO BEND COUNTRY THIS MORNING. SCATTERED CONVECTION SHOULD CONTINUE TO INCREASE IN COVERAGE AND SPREAD NORTH ACROSS THE CWA TODAY ALTHOUGH THE HIGHEST RAIN CHANCES WILL BE ACROSS DEEP EAST TEXAS AND INTO N CNTRL LA. LATEST WV VAPOR IMAGERY INDICATES SOME MID LVL DRY AIR ENTRAINMENT ON THE ERN FLANK OF THE TROUGH WHICH IS BEING DRAWN UP INTO ERN PORTIONS OF THE CWA. HOWEVER...THE UPPER TROUGH IS EXPECTED TO SLOWLY DRIFT EAST ALONG THE GULF COAST WHICH SHOULD DISPLACE THE DRIER AIR FARTHER EAST. DIURNAL HEATING WILL FUEL A GREAT DEAL OF THE CONVECTION TODAY SO MOST OF THE SHWRS/TSTMS SHOULD DIMINISH AFTER SUNSET ESPECIALLY NORTH OF I-20. REDEVELOPMENT ACROSS MOST OF THE AREA IS LIKELY AGAIN DURING THE DAY ON TUESDAY DURING PEAK HEATING BUT COVERAGE MAY BE SOMEWHAT LESS AS THE TROUGH AXIS WILL BE EAST OF THE CWA. A FEW SHWRS OR TSTMS MAY LINGER INTO WEDNESDAY SE OF A LINE FROM KLFK TO KMLU BUT RAIN CHANCES SHOULD QUICKLY COME TO AN END BY LATE WEDNESDAY AFTERNOON. AN UPPER RIDGE WILL BEGIN TO BUILD EAST INTO THE SRN PLAINS BUT WILL FLATTEN THROUGH THE LATTER HALF OF THE WEEK. FLOW ALOFT WILL TRANSITION TO NWLY BRINGING A COLD FRONT INTO THE AREA DURING THE WEEKEND. NLY FLOW IN THE LOWEST LVLS WILL LIKELY KEEP GULF MOISTURE CUT OFF FROM THE REGION SO CHANCES OF RAIN WITH THIS FRONT DO NOT APPEAR VERY PROMISING AT THIS TIME. HOWEVER...WILL MAINTAIN SLIGHT CHANCE POPS SATURDAY AND SUNDAY WITH THE FROPA. THE AFOREMENTIONED LOW LVL DRY AIR THAT ARRIVES LATE THURSDAY/EARLY FRIDAY...FOLLOWED BY THE REINFORCEMENT OF THE COOLER/DRIER AIR BEHIND THE COLD FRONT DURING THE WEEKEND...SHOULD KEEP TEMPERATURES VERY CLOSE TO SEASONAL NORMS FROM FRIDAY THROUGH THE BEGINNING OF NEXT WEEK. /09/ && .PRELIMINARY POINT TEMPS/POPS... SHV 86 70 86 69 / 50 30 40 20 MLU 82 69 85 68 / 50 50 40 20 DEQ 85 66 85 65 / 30 20 30 20 TXK 84 68 84 67 / 40 30 40 20 ELD 83 67 84 66 / 40 40 40 20 TYR 86 69 87 69 / 40 20 30 20 GGG 85 68 86 68 / 40 30 40 20 LFK 84 67 85 68 / 50 30 40 20 && .SHV WATCHES/WARNINGS/ADVISORIES... AR...NONE. LA...NONE. OK...NONE. TX...NONE. && $$ 24/05/09
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
534 PM EDT MON SEP 28 2015 .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 421 PM EDT MON SEP 28 2015 WATER VAPOR IMAGERY AND RAP ANALYSIS SHOW A TROF PROGRESSING ACROSS CNTRL CANADA. TROF IS SUPPORTING A PAIR OF SFC COLD FRONTS. FIRST IS MOVING ACROSS CNTRL UPPER MI ATTM WHILE THE SECOND WHICH MARKS THE LEADING EDGE OF THE NOTABLY COLDER AIR RUNS FROM JAMES BAY TO JUST W OF LAKE SUPERIOR. IMPROVED UPPER DIVERGENCE ASSOCIATED WITH THE RIGHT ENTRANCE OF UPPER JET AND LOW/MID LEVEL FGEN UNDERNEATH HAS SUPPORTED AN EXPANSION OF SHRA AND A FEW TSRA ALONG/JUST BEHIND THE LEAD COLD FRONT TODAY...THOUGH THERE HASN`T BEEN MUCH THUNDER THIS AFTN AFTER AN INCREASE DURING THE MORNING. MODELS ARE IN GOOD AGREEMENT PUSHING COLD FRONTS AND ASSOCIATED PCPN S AND E THIS EVENING. WITH MODELS IN GOOD AGREEMENT ON PCPN FIELDS...UTILIZED A COMBINATION OF MODEL CONSENSUS AND RADAR TRENDS TO CONSTRUCT POP GRIDS THRU THE EVENING. LINGERING UPPER DIVERGENCE ASSOCIATED WITH UPPER JET STREAK AS WELL AS SECOND SFC COLD FRONT SWEEPING SE MAY GENERATE A FEW -SHRA BEHIND THE MAIN AREA OF PCPN TIED MORE CLOSELY TO FIRST COLD FRONT. THUS...SOME LOW POPS WILL BE CARRIED AS LATE AS THE MID TO LATE EVENING OVER THE FAR SCNTRL/SE. OTHERWISE...COLDER AND MUCH DRIER AIR WILL FLOW INTO THE AREA TONIGHT. 850MB TEMPS CURRENTLY AT 10-13C WILL FALL TO -1C OVER THE KEWEENAW TO 7C FAR SCNTRL BY 12Z TUE. THIS WILL RESULT IN A MUCH COOLER OVERNIGHT WITH MIN TEMPS DIPPING TO AROUND 40F AND PROBABLY INTO THE UPPER 30S AT SOME HIER TERRAIN LOCATIONS OVER W AND NW UPPER MI. HIGHEST MINS WILL BE NEAR LAKE MI...UPPER 40S/AROUND 50F. ALTHOUGH THE SFC-850MB DELTA-T BTWN THE LAKE WATERS STILL IN THE MID/UPR 50S F IS SUFFICIENT FOR LAKE CLOUDS/PCPN...FCST SOUNDINGS SHOW THAT THE INCOMING AIR MASS WILL BE EXTREMELY DRY. SO...THE CHILLY AIR FLOW OVER THE LAKE PROBABLY WON`T SUPPORT MUCH MORE THAN SCT CLOUDS OVER THE HIER TERRAIN LATE TONIGHT. 850MB TEMPS BOTTOM OUT AT -1 TO -2C TUE MORNING. WITH FCST SOUNDINGS STILL SHOWING A VERY DRY AIR MASS FLOWING INTO THE UPPER LAKES...NOT EXPECTING MUCH IN THE WAY OF CLOUD COVER. IF ANYTHING...THE MOISTENING PROVIDED BY THE LAKE MAY PROVIDE AN INCREASE IN CLOUD COVER INLAND FOR A TIME IN THE MORNING AS DAYTIME HEATING WORKS ON THE MOISTURE. SHOULDN`T BE ANYTHING MORE THAN SCT CLOUD COVER. OTHERWISE...THE WEATHER WILL FEEL MUCH MORE LIKE FALL WITH HIGH TEMPS IN THE MID 50S TO AROUND 60F AND A RATHER BRISK NW WIND... ESPECIALLY OVER THE E HALF OF THE FCST AREA. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 533 PM EDT MON SEP 28 2015 HIGHS WILL MAINLY BE IN THE 50S FOR HIGHS THROUGH THE PERIOD...WHICH WILL BE THE FIRST STRETCH OF BELOW NORMAL TEMPERATURES FOR QUITE A WHILE /AT LEAST 10 DAYS/. WE BEGIN AT 00Z WEDNESDAY WITH THE LARGE SFC HIGH ACROSS MUCH OF THE UPPER GREAT LAKES...AND THE MAIN 500MB TROUGH EXTENDING FROM N QUEBEC DOWN THROUGH LOWER MI AND THE MS DELTA. FOR UPPER MI MAINLY ZONAL FLOW IS FIGURED ALOFT THROUGH 00Z THURSDAY. DRY WEATHER WILL DOMINATE MUCH OF THIS PERIOD. THE MAIN WEATHER THREAT WILL LIKELY BE THE COLD TUESDAY NIGHT INTO WEDNESDAY MORNING...AND AGAIN WEDNESDAY NIGHT INTO EARLY THURSDAY MORNING. HAVE ISSUED A FREEZE WATCH FOR THE W HALF...MINUS THE KEWEENAW PENINSULA. FROST ADVISORIES MAY BE POSTED FOR THE REST OF THE CWA IF THE CURRENT FCST HOLDS TRUE. THIS WILL BE THANKS TO LOWS OF 27-35F...WITH THE LOWEST VALUES INLAND FROM LAKE SUPERIOR. STAY TUNED AS WINDS WILL BE CALM...AND THE POTENTIAL EXISTS FOR TEMPS TO FALL ANOTHER COUPLE OF DEGREES FROM THE CURRENT FCST. 850MB TEMPS WILL E IN THE -1C RANGE OVER THE KEWEENAW E THROUGH THE N TIER COUNTIES...TO AS WARM AS 1.5-3C OVER MENOMINEE COUNTY /WARMEST OFF THE GFS/. FCST MODELS DO SHOW AN EMBEDDED SHORTWAVE/TROUGH SET UP ACROSS S MANITOBA AT 00Z THURSDAY...BUT THE OVERALL STRENGTH IS DIFFERENT. THE CONSENSUS IS THAT THIS FEATURE WILL GO ON ITS OWN...AND BEGIN TO RETROGRADE...WITH RIDGING AT THE SFC AND ALOFT OVER THE UPPER GREAT LAKES. ALTHOUGH THE MAIN SFC HIGH WILL SHIFT NE MORE INTO QUEBEC...THE RIDGE WILL BE WELL ESTABLISHED OVERHEAD. ONLY HAVE SLIGHT CHANCE POPS FOR THE KEWEENAW SUNDAY...AND MAINLY JUST ALONG LAKE SUPERIOR SUNDAY NIGHT. THIS LOOKS REASONABLE...BUT WILL NOT INCREASE THE POTENTIAL. MODELS ARE PRETTY CONSISTENT WITH THE OVERALL PATTERN THROUGH WEDNESDAY EVENING. HOWEVER...THE GFS HAS A DEEPER 500MB LOW OVER QUEBEC RETROGRADING AS CLOSE AS THE E HALF OF QUEBEC BY 18Z SATURDAY. THE ECMWF IS NOT AS IMPRESSIVE AND IS MORE FOCUSED ON THE S 500MB LOW SPINNING OVER THE SE STATES. WILL KEEP A GENERAL BLEND UNTIL A MORE CONCRETE SOLUTION APPEARS. EITHER WAY...COOL WEATHER AND A MAINLY N FLOW SHOULD REMAIN ACROSS UPPER MI. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 201 PM EDT MON SEP 28 2015 A COLD FRONT OVER WRN UPPER MI WILL PASS THRU KSAW IN THE NEXT FEW HRS. A SECONDARY COLD FRONT WILL THEN FOLLOW THIS EVENING AND OVERNIGHT. -SHRA ASSOCIATED WITH THE FIRST COLD FRONT WILL AFFECT KSAW FOR MUCH OF THE AFTN WITH MVFR CONDITIONS LIKELY PREVAILING FOR THE NEXT FEW HRS. TO THE W...INCOMING DRIER AIR HAS ALREADY RESULTED IN LOW CLOUDS CLEARING OUT AT KIWD/KCMX...AND VFR CONDITIONS WILL BE THE RULE AT THOSE TERMINALS THIS AFTN. BEHIND THE SECOND COLD FRONT...NW WINDS WILL INCREASE...ESPECIALLY AT KCMX WHERE WINDS WILL LIKELY GUST TO AROUND 25KT. INCOMING CHILLY AIR MASS WILL BE VERY DRY...SO NOT EXPECTING ANYTHING MORE THAN SCT LAKE EFFECT CLOUDS TO DEVELOP LATE TONIGHT/TUE MORNING...ALLOWING VFR CONDITIONS TO PREVAIL AT KIWD/KCMX/KSAW TONIGHT/TUE. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 421 PM EDT MON SEP 28 2015 WITH ONE COLD FRONT EXITING LAKE SUPERIOR NOW...A SECOND COLD FRONT WILL SWEEP ACROSS THE LAKE TONIGHT. PRES RISES ALONG WITH INCREASING OVERWATER INSTABILITY AS COLDER AIR FLOWS INTO THE UPPER LAKES WILL RESULT IN NW WINDS INCREASING TO 20-30KT TONIGHT AFTER THE SECOND COLD FRONT PASSES. WHILE WINDS WILL REMAIN MOSTLY IN THE 20-30KT RANGE OVER ERN LAKE SUPERIOR TUE...WINDS WILL DIMINISH OVER THE WRN LAKE AS HIGH PRES APPROACHES. WINDS WILL THEN DIMINISH TO MOSTLY UNDER 15KT W TO E TUE NIGHT/WED AS HIGH PRES SETTLES OVER THE UPPER LAKES. AS THE HIGH DRIFTS TO THE ENE THRU THE END OF THE WEEK...IT WILL EXTEND A RIDGE BACK TOWARD THE UPPER LAKES. SINCE IT LOOKS LIKE THE RIDGE MAY BE SITUATED A LITTLE FARTHER N THAN PREVIOUSLY EXPECTED...EASTERLY WINDS MAY BECOME BRISK INTO THE 15-25KT RANGE AT TIMES DURING THE LATE WEEK PERIOD. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... FREEZE WATCH FROM LATE TUESDAY NIGHT THROUGH WEDNESDAY MORNING FOR MIZ002-004-009-010-084. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...ROLFSON LONG TERM...KF AVIATION...ROLFSON MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
421 PM EDT MON SEP 28 2015 .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 421 PM EDT MON SEP 28 2015 WATER VAPOR IMAGERY AND RAP ANALYSIS SHOW A TROF PROGRESSING ACROSS CNTRL CANADA. TROF IS SUPPORTING A PAIR OF SFC COLD FRONTS. FIRST IS MOVING ACROSS CNTRL UPPER MI ATTM WHILE THE SECOND WHICH MARKS THE LEADING EDGE OF THE NOTABLY COLDER AIR RUNS FROM JAMES BAY TO JUST W OF LAKE SUPERIOR. IMPROVED UPPER DIVERGENCE ASSOCIATED WITH THE RIGHT ENTRANCE OF UPPER JET AND LOW/MID LEVEL FGEN UNDERNEATH HAS SUPPORTED AN EXPANSION OF SHRA AND A FEW TSRA ALONG/JUST BEHIND THE LEAD COLD FRONT TODAY...THOUGH THERE HASN`T BEEN MUCH THUNDER THIS AFTN AFTER AN INCREASE DURING THE MORNING. MODELS ARE IN GOOD AGREEMENT PUSHING COLD FRONTS AND ASSOCIATED PCPN S AND E THIS EVENING. WITH MODELS IN GOOD AGREEMENT ON PCPN FIELDS...UTILIZED A COMBINATION OF MODEL CONSENSUS AND RADAR TRENDS TO CONSTRUCT POP GRIDS THRU THE EVENING. LINGERING UPPER DIVERGENCE ASSOCIATED WITH UPPER JET STREAK AS WELL AS SECOND SFC COLD FRONT SWEEPING SE MAY GENERATE A FEW -SHRA BEHIND THE MAIN AREA OF PCPN TIED MORE CLOSELY TO FIRST COLD FRONT. THUS...SOME LOW POPS WILL BE CARRIED AS LATE AS THE MID TO LATE EVENING OVER THE FAR SCNTRL/SE. OTHERWISE...COLDER AND MUCH DRIER AIR WILL FLOW INTO THE AREA TONIGHT. 850MB TEMPS CURRENTLY AT 10-13C WILL FALL TO -1C OVER THE KEWEENAW TO 7C FAR SCNTRL BY 12Z TUE. THIS WILL RESULT IN A MUCH COOLER OVERNIGHT WITH MIN TEMPS DIPPING TO AROUND 40F AND PROBABLY INTO THE UPPER 30S AT SOME HIER TERRAIN LOCATIONS OVER W AND NW UPPER MI. HIGHEST MINS WILL BE NEAR LAKE MI...UPPER 40S/AROUND 50F. ALTHOUGH THE SFC-850MB DELTA-T BTWN THE LAKE WATERS STILL IN THE MID/UPR 50S F IS SUFFICIENT FOR LAKE CLOUDS/PCPN...FCST SOUNDINGS SHOW THAT THE INCOMING AIR MASS WILL BE EXTREMELY DRY. SO...THE CHILLY AIR FLOW OVER THE LAKE PROBABLY WON`T SUPPORT MUCH MORE THAN SCT CLOUDS OVER THE HIER TERRAIN LATE TONIGHT. 850MB TEMPS BOTTOM OUT AT -1 TO -2C TUE MORNING. WITH FCST SOUNDINGS STILL SHOWING A VERY DRY AIR MASS FLOWING INTO THE UPPER LAKES...NOT EXPECTING MUCH IN THE WAY OF CLOUD COVER. IF ANYTHING...THE MOISTENING PROVIDED BY THE LAKE MAY PROVIDE AN INCREASE IN CLOUD COVER INLAND FOR A TIME IN THE MORNING AS DAYTIME HEATING WORKS ON THE MOISTURE. SHOULDN`T BE ANYTHING MORE THAN SCT CLOUD COVER. OTHERWISE...THE WEATHER WILL FEEL MUCH MORE LIKE FALL WITH HIGH TEMPS IN THE MID 50S TO AROUND 60F AND A RATHER BRISK NW WIND... ESPECIALLY OVER THE E HALF OF THE FCST AREA. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 415 PM EDT MON SEP 28 2015 HIGHS WILL MAINLY BE IN THE 50S FOR HIGHS THROUGH THE PERIOD...WHICH WILL BE THE FIRST STRETCH OF BELOW NORMAL TEMPERATURES FOR QUITE A WHILE /AT LEAST 10 DAYS/. WE BEGIN AT 00Z WEDNESDAY WITH THE LARGE SFC HIGH ACROSS MUCH OF THE UPPER GREAT LAKES...AND THE MAIN 500MB TROUGH EXTENDING FROM N QUEBEC DOWN THROUGH LOWER MI AND THE MS DELTA. FOR UPPER MI MAINLY ZONAL FLOW IS FIGURED ALOFT THROUGH 00Z THURSDAY. DRY WEATHER WILL DOMINATE MUCH OF THIS PERIOD. THE MAIN WEATHER THREAT WILL LIKELY BE THE COLD TUESDAY NIGHT INTO WEDNESDAY MORNING...AND AGAIN WEDNESDAY NIGHT INTO EARLY THURSDAY MORNING. HAVE ISSUED A FREEZE WATCH FOR THE W HALF...MINUS THE KEWEENAW PENINSULA. WIND CHILL ADVISORIES MAY BE POSTED FOR THE REST OF THE CWA IF THE CURRENT FCST HOLDS TRUE. THIS WILL BE THANKS TO LOWS OF 27-35F...WITH THE LOWEST VALUES INLAND FROM LAKE SUPERIOR. STAY TUNED AS WINDS WILL BE CALM...AND THE POTENTIAL EXISTS FOR TEMPS TO FALL ANOTHER COUPLE OF DEGREES FROM THE CURRENT FCST. 850MB TEMPS WILL E IN THE -1C RANGE OVER THE KEWEENAW E THROUGH THE N TIER COUNTIES...TO AS WARM AS 1.5-3C OVER MENOMINEE COUNTY /WARMEST OFF THE GFS/. FCST MODELS DO SHOW AN EMBEDDED SHORTWAVE/TROUGH SET UP ACROSS S MANITOBA AT 00Z THURSDAY...BUT THE OVERALL STRENGTH IS DIFFERENT. THE CONSENSUS IS THAT THIS FEATURE WILL GO ON ITS OWN...AND BEGIN TO RETROGRADE...WITH RIDGING AT THE SFC AND ALOFT OVER THE UPPER GREAT LAKES. ALTHOUGH THE MAIN SFC HIGH WILL SHIFT NE MORE INTO QUEBEC...THE RIDGE WILL BE WELL ESTABLISHED OVERHEAD. ONLY HAVE SLIGHT CHANCE POPS FOR THE KEWEENAW SUNDAY...AND MAINLY JUST ALONG LAKE SUPERIOR SUNDAY NIGHT. THIS LOOKS REASONABLE...BUT WILL NOT INCREASE THE POTENTIAL. MODELS ARE PRETTY CONSISTENT WITH THE OVERALL PATTERN THROUGH WEDNESDAY EVENING. HOWEVER...THE GFS HAS A DEEPER 500MB LOW OVER QUEBEC RETROGRADING AS CLOSE AS THE E HALF OF QUEBEC BY 18Z SATURDAY. THE ECMWF IS NOT AS IMPRESSIVE AND IS MORE FOCUSED ON THE S 500MB LOW SPINNING OVER THE SE STATES. WILL KEEP A GENERAL BLEND UNTIL A MORE CONCRETE SOLUTION APPEARS. EITHER WAY...COOL WEATHER AND A MAINLY N FLOW SHOULD REMAIN ACROSS UPPER MI. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 201 PM EDT MON SEP 28 2015 A COLD FRONT OVER WRN UPPER MI WILL PASS THRU KSAW IN THE NEXT FEW HRS. A SECONDARY COLD FRONT WILL THEN FOLLOW THIS EVENING AND OVERNIGHT. -SHRA ASSOCIATED WITH THE FIRST COLD FRONT WILL AFFECT KSAW FOR MUCH OF THE AFTN WITH MVFR CONDITIONS LIKELY PREVAILING FOR THE NEXT FEW HRS. TO THE W...INCOMING DRIER AIR HAS ALREADY RESULTED IN LOW CLOUDS CLEARING OUT AT KIWD/KCMX...AND VFR CONDITIONS WILL BE THE RULE AT THOSE TERMINALS THIS AFTN. BEHIND THE SECOND COLD FRONT...NW WINDS WILL INCREASE...ESPECIALLY AT KCMX WHERE WINDS WILL LIKELY GUST TO AROUND 25KT. INCOMING CHILLY AIR MASS WILL BE VERY DRY...SO NOT EXPECTING ANYTHING MORE THAN SCT LAKE EFFECT CLOUDS TO DEVELOP LATE TONIGHT/TUE MORNING...ALLOWING VFR CONDITIONS TO PREVAIL AT KIWD/KCMX/KSAW TONIGHT/TUE. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 421 PM EDT MON SEP 28 2015 WITH ONE COLD FRONT EXITING LAKE SUPERIOR NOW...A SECOND COLD FRONT WILL SWEEP ACROSS THE LAKE TONIGHT. PRES RISES ALONG WITH INCREASING OVERWATER INSTABILITY AS COLDER AIR FLOWS INTO THE UPPER LAKES WILL RESULT IN NW WINDS INCREASING TO 20-30KT TONIGHT AFTER THE SECOND COLD FRONT PASSES. WHILE WINDS WILL REMAIN MOSTLY IN THE 20-30KT RANGE OVER ERN LAKE SUPERIOR TUE...WINDS WILL DIMINISH OVER THE WRN LAKE AS HIGH PRES APPROACHES. WINDS WILL THEN DIMINISH TO MOSTLY UNDER 15KT W TO E TUE NIGHT/WED AS HIGH PRES SETTLES OVER THE UPPER LAKES. AS THE HIGH DRIFTS TO THE ENE THRU THE END OF THE WEEK...IT WILL EXTEND A RIDGE BACK TOWARD THE UPPER LAKES. SINCE IT LOOKS LIKE THE RIDGE MAY BE SITUATED A LITTLE FARTHER N THAN PREVIOUSLY EXPECTED...EASTERLY WINDS MAY BECOME BRISK INTO THE 15-25KT RANGE AT TIMES DURING THE LATE WEEK PERIOD. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... FREEZE WATCH FROM LATE TUESDAY NIGHT THROUGH WEDNESDAY MORNING FOR MIZ002-004-009-010-084. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...ROLFSON LONG TERM...KF AVIATION...ROLFSON MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
420 PM EDT MON SEP 28 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 419 AM EDT MON SEP 28 2015 00Z RAOBS/LATEST WV IMAGERY AND RAP ANALYSIS SHOW ZONAL FLOW ALONG THE CNDN BORDER AS RATHER SHEARED SHRTWV STRETCHING FM THE NRN PLAINS INTO NW ONTARIO HAS WEAKENED THE UPR RDG THAT HAS BEEN SO PERSISTENT RECENTLY OVER ERN NAMERICA. THIS SHRTWV IS SUPPORTING A SFC COLD FNT THAT IS MOVING E THRU WRN LK SUP EARLY THIS MRNG. SINCE THIS DISTURBANCE IS SHEARED OUT AND THE MSTR INFLOW IN THE SW FLOW AHEAD OF THE FNT IS RATHER MODEST...SHOWER COVERAGE AHEAD OF THE INCOMING FNT IS RATHER LIMITED...WITH SCT COVERAGE LIMITED BY THE HIER STABILITY/DRY MID LVLS SHOWN ON THE 00Z MPX RAOB. CLDS IN ADVANCE OF THE FNT ARE PUSHING THRU THE WRN CWA...BUT THERE IS AN AXIS OF MOCLR SKIES OVER THE CENTRAL TO W OF SOME LO CLDS ACRS THE SE HALF OF THE CWA ASSOCIATED WITH LLVL MSTR SHOWN ON THE 00Z GRB/APX RAOBS. STEADY SW WINDS IN THE WARM SECTOR ARE KEEPING TEMPS WELL ABOVE NORMAL NOT FAR FM 60 EVEN WHERE THE SKY IS MOCLR. LOOKING FARTHER TO THE W...THE 00Z ABERDEEN SDAKOTA ROAB SHOWS A VERY DRY AIRMASS IS UNDER SFC HI PRES RDG TRAILING THE SFC COLD FNT. BUT FARTHER TO THE W...THERE IS AN AREA OF COLDER CLD TOPS/SHOWERS/EVEN SOME LTG STRIKES MOVING THRU THE NRN PLAINS. MODELS SHOW AREA OF UPR DVGC/MID LVL FGEN IN RRQ OF 100KT H3 JET MAX SUPPORTING THE NW ONTARIO SHRTWV IS OVER THIS AREA OF COLDER CLD TOPS. ANOTHER SHRTWV IS DIGGING THRU SCENTRAL CANADA AND DEEPENING AN UPR TROF THERE. MAIN FCST CONCERNS IN THE SHORT TERM FOCUS ON POPS ASSOCIATED WITH COLD FNT THAT WL BE CROSSING UPR MI TODAY. TODAY...LATEST SHORT TERM GUIDANCE IS IN GOOD AGREEMENT SHOWING SFC COLD FNT CROSSING UPR MI TODAY AND REACHING LK MI ARND 21Z. SINCE UPR DVGC/AXIS OF MID LVL FGEN SUPPORTING AREA OF DISTURBED WX IN THE NRN PLAINS IS FCST TO MOVE OVER THE UPR LKS WHILE THE FNT IS CROSSING THE CWA...MOST OF THE MODELS SHOW SHOWER COVERAGE EXPANDING WITH TIME. SINCE THE DRY AIR SHOWN ON THE ABERDEEN RAOB AND TRAILING THE FNT IS MOST LIKELY TO IMPACT THE WRN CWA BEFORE THE ARRIVAL...WL FCST THE HIEST LIKELY POPS OVER THE SE HALF OF UPR MI THIS AFTN. ALTHOUGH THERE HAVE BEEN SOME LTG STRIKES OBSVD UPSTREAM...MODEL FCST MUCAPES NO HIER THAN ABOUT 100 J/KG OVER THE CWA SUPPORT LEAVING TS OUT OF THE FCST FOR NOW. WITH EARLIER COLD FROPA OVER THE W...TEMPS THERE WL BE MUCH LOWER THAN YDAY. TNGT...MODELS DIFFER ON HOW QUICKLY THE SHOWERS EXIT THE SE CWA THIS EVNG. THE 00Z NAM IS QUITE A BIT SLOWER THAN THE REST OF THE GUIDANCE...BUT FAVOR THE FASTER DRYING TREND SHOWN BY THE MAJORITY OF THE OTHER MODELS GIVEN DRYNESS OF THE TRAILING AIRMASS DEPICTED ON THE 00Z ABERDEEN RAOB. THESE MODELS FAVOR SOME LINGERING HIER LIKELY POPS EARLY IN THE EVNG OVER THE SE BEFORE VIGOROUS DRYING BRINGS A CLRG TREND EVEN THOUGH ANOTHER COLD FNT ASSOCIATED WITH SHRTWV NOW DIGGING THRU SCENTRAL CANADA IS PROGGED TO PASS OVERNGT. H85 TEMPS DROPPING TO ARND 0C OVER THE KEWEENAW BY 12Z TUE WL RESULT IN A MUCH COOLER OVERNGT WITH MIN TEMPS DIPPING TO ARND 40 AND PERHAPS THE UPR 30S AT SOME OF THE HIER TERRAIN LOCATIONS. STRONG NW FLOW OVER THE RELATIVELY WARM LK WATERS WL LIMIT THE TEMP DROP. ALTHOUGH THE SFC-H85 DELTA T BTWN THE RELATIVELY WARM LK WATERS /MID TO UPR 50S F/IS SUFFICIENT FOR LK CLDS/PCPN...THE INCOMING AIRMASS WL BE TOO DRY AND THE LLVL FLOW TOO ACYC TO SUPPORT MORE THAN SCT CLDS OVER THE HIER TERRAIN. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 415 PM EDT MON SEP 28 2015 HIGHS WILL MAINLY BE IN THE 50S FOR HIGHS THROUGH THE PERIOD...WHICH WILL BE THE FIRST STRETCH OF BELOW NORMAL TEMPERATURES FOR QUITE A WHILE /AT LEAST 10 DAYS/. WE BEGIN AT 00Z WEDNESDAY WITH THE LARGE SFC HIGH ACROSS MUCH OF THE UPPER GREAT LAKES...AND THE MAIN 500MB TROUGH EXTENDING FROM N QUEBEC DOWN THROUGH LOWER MI AND THE MS DELTA. FOR UPPER MI MAINLY ZONAL FLOW IS FIGURED ALOFT THROUGH 00Z THURSDAY. DRY WEATHER WILL DOMINATE MUCH OF THIS PERIOD. THE MAIN WEATHER THREAT WILL LIKELY BE THE COLD TUESDAY NIGHT INTO WEDNESDAY MORNING...AND AGAIN WEDNESDAY NIGHT INTO EARLY THURSDAY MORNING. HAVE ISSUED A FREEZE WATCH FOR THE W HALF...MINUS THE KEWEENAW PENINSULA. WIND CHILL ADVISORIES MAY BE POSTED FOR THE REST OF THE CWA IF THE CURRENT FCST HOLDS TRUE. THIS WILL BE THANKS TO LOWS OF 27-35F...WITH THE LOWEST VALUES INLAND FROM LAKE SUPERIOR. STAY TUNED AS WINDS WILL BE CALM...AND THE POTENTIAL EXISTS FOR TEMPS TO FALL ANOTHER COUPLE OF DEGREES FROM THE CURRENT FCST. 850MB TEMPS WILL E IN THE -1C RANGE OVER THE KEWEENAW E THROUGH THE N TIER COUNTIES...TO AS WARM AS 1.5-3C OVER MENOMINEE COUNTY /WARMEST OFF THE GFS/. FCST MODELS DO SHOW AN EMBEDDED SHORTWAVE/TROUGH SET UP ACROSS S MANITOBA AT 00Z THURSDAY...BUT THE OVERALL STRENGTH IS DIFFERENT. THE CONSENSUS IS THAT THIS FEATURE WILL GO ON ITS OWN...AND BEGIN TO RETROGRADE...WITH RIDGING AT THE SFC AND ALOFT OVER THE UPPER GREAT LAKES. ALTHOUGH THE MAIN SFC HIGH WILL SHIFT NE MORE INTO QUEBEC...THE RIDGE WILL BE WELL ESTABLISHED OVERHEAD. ONLY HAVE SLIGHT CHANCE POPS FOR THE KEWEENAW SUNDAY...AND MAINLY JUST ALONG LAKE SUPERIOR SUNDAY NIGHT. THIS LOOKS REASONABLE...BUT WILL NOT INCREASE THE POTENTIAL. MODELS ARE PRETTY CONSISTENT WITH THE OVERALL PATTERN THROUGH WEDNESDAY EVENING. HOWEVER...THE GFS HAS A DEEPER 500MB LOW OVER QUEBEC RETROGRADING AS CLOSE AS THE E HALF OF QUEBEC BY 18Z SATURDAY. THE ECMWF IS NOT AS IMPRESSIVE AND IS MORE FOCUSED ON THE S 500MB LOW SPINNING OVER THE SE STATES. WILL KEEP A GENERAL BLEND UNTIL A MORE CONCRETE SOLUTION APPEARS. EITHER WAY...COOL WEATHER AND A MAINLY N FLOW SHOULD REMAIN ACROSS UPPER MI. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 201 PM EDT MON SEP 28 2015 A COLD FRONT OVER WRN UPPER MI WILL PASS THRU KSAW IN THE NEXT FEW HRS. A SECONDARY COLD FRONT WILL THEN FOLLOW THIS EVENING AND OVERNIGHT. -SHRA ASSOCIATED WITH THE FIRST COLD FRONT WILL AFFECT KSAW FOR MUCH OF THE AFTN WITH MVFR CONDITIONS LIKELY PREVAILING FOR THE NEXT FEW HRS. TO THE W...INCOMING DRIER AIR HAS ALREADY RESULTED IN LOW CLOUDS CLEARING OUT AT KIWD/KCMX...AND VFR CONDITIONS WILL BE THE RULE AT THOSE TERMINALS THIS AFTN. BEHIND THE SECOND COLD FRONT...NW WINDS WILL INCREASE...ESPECIALLY AT KCMX WHERE WINDS WILL LIKELY GUST TO AROUND 25KT. INCOMING CHILLY AIR MASS WILL BE VERY DRY...SO NOT EXPECTING ANYTHING MORE THAN SCT LAKE EFFECT CLOUDS TO DEVELOP LATE TONIGHT/TUE MORNING...ALLOWING VFR CONDITIONS TO PREVAIL AT KIWD/KCMX/KSAW TONIGHT/TUE. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 419 AM EDT MON SEP 28 2015 SW WINDS UP TO 25 KTS THIS MRNG AHEAD OF A COLD FRONT MOVING THRU WESTERN LAKE SUPERIOR EARLY THIS MORNING WILL SHIFT TO THE W-NW UP TO 20 KTS FOLLOWING THE FRONTAL PASSAGE BY EARLY AFTERNOON OVER THE FAR EAST. ANOTHER COLD FRONT WILL SWING ACROSS THE LAKE TONIGHT. EXPECT NNW WINDS TO INCREASE UP TO 25-30 KTS IN ITS WAKE LATE TONIGHT/TUE. AS A TRAILING HIGH PRESSURE CLOSES IN ON THE AREA ON TUE NIGHT/WED...WINDS WILL DIMINISH TO UNDER 15-20 KTS. ONCE THE HIGH SHIFTS INTO QUEBEC LATER IN THE WEEK...E WINDS UP TO 20 KTS WILL DOMINATE. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... FREEZE WATCH FROM LATE TUESDAY NIGHT THROUGH WEDNESDAY MORNING FOR MIZ002-004-009-010-084. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...KC LONG TERM...KF AVIATION...ROLFSON MARINE...KC
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
320 PM EDT MON SEP 28 2015 LATEST UPDATE... SYNOPSIS/SHORT TERM/LONG TERM/MARINE .SYNOPSIS... ISSUED AT 320 PM EDT MON SEP 28 2015 A COLD FRONT WILL MOVE SOUTH THROUGH THE AREA OVERNIGHT...BRINGING RAIN SHOWERS WITH IT. THIS WILL BE FOLLOWED BY DRY CONDITIONS AND A GRADUAL COOLING TREND WITH HIGH TEMPERATURES STRUGGLING TO REACH 60 BY THE END OF THE WEEK. && .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT) ISSUED AT 320 PM EDT MON SEP 28 2015 NO SIGNIFICANT CHANGES WERE MADE TO THE FORECAST. STILL EXPECT A BAND OF PREDOMINANTLY RAIN SHOWERS TO MOVE THROUGH THE AREA OVERNIGHT. MAIN CHALLENGE IS THE CHARACTER OF PRECIPITATION MOVING THROUGH THE FORECAST AREA OVERNIGHT. SIMULATED REFLECTIVITY FROM THE ESRL EXPERIMENTAL HRRR SHOWS SUBSTANTIALLY LESS COVERAGE THAN THE OPERATIONAL NCEP HRRR DOES. INCLUDED THUNDER FOR OUR NORTHEAST ZONES AS SPC MESOANALYSIS CURRENTLY SHOWS A CORRIDOR OF MUCAPE GREATER THAN 1000 J PER KG EXTENDING FROM NORTHERN LOWER MI INTO SOUTHEASTERN LOWER MI. OVERALL THREAT FOR THUNDER WILL BE LOW AS THE FRONT PASSES THROUGH THE AREA IN THE EARLY MORNING HOURS WELL AFTER PEAK INSOLATION. NO CONCERNS AFTER THIS FOR THE REST OF THE FORECAST PERIOD. .LONG TERM...(THURSDAY THROUGH MONDAY) ISSUED AT 320 PM EDT MON SEP 28 2015 DECIDED TO KEEP THE EXTENDED PERIOD DRY THOUGH THERE ARE SOME CAVEATS TO THIS. FIRST...WITH SOMEWHAT MOIST H1000-H850 NE FLOW OFF LAKE HURON THURSDAY THROUGH SATURDAY COMBINED WITH DECREASING H850 TEMPS...THERE COULD BE A FEW LAKE EFFECT SHOWERS MOVING TOWARD CENTRAL LOWER MI DURING THIS TIME FRAME. MEDIUM RANGE GUIDANCE IS NOT INDICATING ANY MEASURABLE PRECIP COMING OFF THE LAKE...BUT IT IS SOMETHING WE WILL NEED TO FINE TUNE AS WE GET CLOSER. SECOND...THE MODELS HAVE BEEN SENDING MIXED SIGNALS ON A TROPICAL DISTURBANCE PRESENTLY IN THE GULF AS WELL AS TD 11 EAST OF FLORIDA. LAST NIGHT`S GEM SOLUTION BROUGHT THE GULF SYSTEM RIGHT INTO MICHIGAN THURSDAY AND FRIDAY...WHICH IS NOT ON THE 12Z RUN. THE LATEST ECMWF BRINGS TD 11 NORTH AND THEN ABRUPTLY WEST INTO THE MID ATLANTIC REGION BY THE WEEKEND...BRINGING A PRECIP SHIELD AS FAR WEST AS LOWER MI BY SATURDAY. THIS IS A DEVIATION FROM THE PRIOR RUN AS WELL AS OTHER MODEL RUNS. THERE IS NO CONFIDENCE IN ANY SIGNIFICANT RAIN MAKING INTO OUR REGION AT THIS TIME...SO WILL KEEP THINGS DRY. THE GFS AND FIM ARE INDICATING SUSTAINED SFC WINDS OF 15-20 KTS COMING OFF LAKE HURON THURSDAY AND FRIDAY...IMPACTING AREAS ESPECIALLY EAST OF US 131. WITH H850 WINDS OF AROUND 25 KTS...THIS SEEMS TO MAKE SENSE AS WE SHOULD BE MIXING TO AROUND THAT HEIGHT...BUT PROBABLY NO FURTHER GIVEN THE CAA UNDERWAY. HIGH TEMPERATURES MAY NOT MAKE 60 FOR MANY AREAS FRIDAY AND SATURDAY...AND COMBINED WITH SOMEWHAT BREEZY CONDITIONS...IT WILL CERTAINLY FEEL LIKE OCTOBER HAS ARRIVED. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 139 PM EDT MON SEP 28 2015 IFR IS UNLIKELY THROUGH LATE EVENING OUTSIDE OF BRIEF POCKETS OF SUB-1K FT CIGS NEAR MKG AND A LOW THREAT AT GRR. I DO NOT EXPECT THIS TO BE SIGNIFICANT ENOUGH TO MENTION IN THE TAFS. MORE IMPORTANTLY...A PERIOD OF IFR APPEARS LIKELY AS A COLD FRONT MOVES INTO SOUTHERN LOWER MI EARLY TUESDAY MORNING. THIS WOULD MAINLY BE FOR LOWER CIGS...THOUGH SOME LOWER VIS TO 2 MILES OR LESS IS POSSIBLE. CURRENT OBSERVATIONS ALONG THE FRONT IN NORTHERN WI SUPPORT THIS TREND. LIGHT RAIN IS EXPECTED THROUGH THE MORNING PERIOD...WITH TSRA NOT LIKELY. WINDS BEHIND THE FRONT ARE EXPECTED TO BE 10 KNOTS OR GREATER OUT OF THE N/NE. && .MARINE... ISSUED AT 320 PM EDT MON SEP 28 2015 LITTLE CHANGE TO THE PREVIOUS DISCUSSION. A SMALL CRAFT ADVISORY IS IN EFFECT FOR INCREASING WINDS AND WAVES OVERNIGHT. ELEVATED WINDS AND WAVES WILL PERSIST MOST OF TUESDAY. CONFIDENCE WITH RESPECT TO WINDS...WAVES...AND TIMING IS MARGINALLY GOOD. LATEST WAVEWATCH 3 RUN IS PRETTY CONSISTENT WITH THE PREVIOUS RUN. AS NOTED BEFORE... THE WHITEHALL TO GRAND HAVEN AREA MAY BE SHELTERED FROM THE LARGER WAVES BY THE SABLE POINTS TO THE NORTH...SO HAVE LEFT THIS AREA OUT OF THE ADVISORY FOR NOW. THIS ADMITTEDLY MAY BE A BIT TOO PRECISE THIS FAR OUT...SO THIS AREA COULD GET ADDED TO THE ADVISORY WITH FUTURE UPDATES. A LIKELY SCENARIO IS THAT HIGHER WAVES WILL PERSIST CONSIDERABLY LONGER SOUTH OF SOUTH HAVEN WITH THE FAVORABLE FETCH...ALLOWING POINTS FARTHER NORTH TO SEE AN EARLIER CANCELLATION. 3 TO 5 FOOT WAVES COULD END UP PERSISTING WELL INTO WEDNESDAY MORNING AROUND SOUTH HAVEN AND POINTS FARTHER SOUTH...WHICH WOULD REQUIRE AN EXTENSION IN TIME OF THIS ADVISORY. && .HYDROLOGY... ISSUED AT 1223 PM EDT MON SEP 28 2015 CURRENT STREAMFLOW AND SOIL MOISTURE ACROSS SOUTHWEST LOWER MICHIGAN ARE BOTH RUNNING NEAR NORMAL. NO SIGNIFICANT CHANGES ARE FORECAST... AS LESS THAN A HALF INCH OF RAIN IS EXPECTED THROUGH THE WEEK. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...NONE. LM...SMALL CRAFT ADVISORY FROM 8 AM TUESDAY TO 2 AM EDT WEDNESDAY FOR LMZ844>846-848-849. && $$ SYNOPSIS...TJT SHORT TERM...TJT LONG TERM...HOVING AVIATION...HOVING HYDROLOGY...63 MARINE...TJT
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
201 PM EDT MON SEP 28 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 419 AM EDT MON SEP 28 2015 00Z RAOBS/LATEST WV IMAGERY AND RAP ANALYSIS SHOW ZONAL FLOW ALONG THE CNDN BORDER AS RATHER SHEARED SHRTWV STRETCHING FM THE NRN PLAINS INTO NW ONTARIO HAS WEAKENED THE UPR RDG THAT HAS BEEN SO PERSISTENT RECENTLY OVER ERN NAMERICA. THIS SHRTWV IS SUPPORTING A SFC COLD FNT THAT IS MOVING E THRU WRN LK SUP EARLY THIS MRNG. SINCE THIS DISTURBANCE IS SHEARED OUT AND THE MSTR INFLOW IN THE SW FLOW AHEAD OF THE FNT IS RATHER MODEST...SHOWER COVERAGE AHEAD OF THE INCOMING FNT IS RATHER LIMITED...WITH SCT COVERAGE LIMITED BY THE HIER STABILITY/DRY MID LVLS SHOWN ON THE 00Z MPX RAOB. CLDS IN ADVANCE OF THE FNT ARE PUSHING THRU THE WRN CWA...BUT THERE IS AN AXIS OF MOCLR SKIES OVER THE CENTRAL TO W OF SOME LO CLDS ACRS THE SE HALF OF THE CWA ASSOCIATED WITH LLVL MSTR SHOWN ON THE 00Z GRB/APX RAOBS. STEADY SW WINDS IN THE WARM SECTOR ARE KEEPING TEMPS WELL ABOVE NORMAL NOT FAR FM 60 EVEN WHERE THE SKY IS MOCLR. LOOKING FARTHER TO THE W...THE 00Z ABERDEEN SDAKOTA ROAB SHOWS A VERY DRY AIRMASS IS UNDER SFC HI PRES RDG TRAILING THE SFC COLD FNT. BUT FARTHER TO THE W...THERE IS AN AREA OF COLDER CLD TOPS/SHOWERS/EVEN SOME LTG STRIKES MOVING THRU THE NRN PLAINS. MODELS SHOW AREA OF UPR DVGC/MID LVL FGEN IN RRQ OF 100KT H3 JET MAX SUPPORTING THE NW ONTARIO SHRTWV IS OVER THIS AREA OF COLDER CLD TOPS. ANOTHER SHRTWV IS DIGGING THRU SCENTRAL CANADA AND DEEPENING AN UPR TROF THERE. MAIN FCST CONCERNS IN THE SHORT TERM FOCUS ON POPS ASSOCIATED WITH COLD FNT THAT WL BE CROSSING UPR MI TODAY. TODAY...LATEST SHORT TERM GUIDANCE IS IN GOOD AGREEMENT SHOWING SFC COLD FNT CROSSING UPR MI TODAY AND REACHING LK MI ARND 21Z. SINCE UPR DVGC/AXIS OF MID LVL FGEN SUPPORTING AREA OF DISTURBED WX IN THE NRN PLAINS IS FCST TO MOVE OVER THE UPR LKS WHILE THE FNT IS CROSSING THE CWA...MOST OF THE MODELS SHOW SHOWER COVERAGE EXPANDING WITH TIME. SINCE THE DRY AIR SHOWN ON THE ABERDEEN RAOB AND TRAILING THE FNT IS MOST LIKELY TO IMPACT THE WRN CWA BEFORE THE ARRIVAL...WL FCST THE HIEST LIKELY POPS OVER THE SE HALF OF UPR MI THIS AFTN. ALTHOUGH THERE HAVE BEEN SOME LTG STRIKES OBSVD UPSTREAM...MODEL FCST MUCAPES NO HIER THAN ABOUT 100 J/KG OVER THE CWA SUPPORT LEAVING TS OUT OF THE FCST FOR NOW. WITH EARLIER COLD FROPA OVER THE W...TEMPS THERE WL BE MUCH LOWER THAN YDAY. TNGT...MODELS DIFFER ON HOW QUICKLY THE SHOWERS EXIT THE SE CWA THIS EVNG. THE 00Z NAM IS QUITE A BIT SLOWER THAN THE REST OF THE GUIDANCE...BUT FAVOR THE FASTER DRYING TREND SHOWN BY THE MAJORITY OF THE OTHER MODELS GIVEN DRYNESS OF THE TRAILING AIRMASS DEPICTED ON THE 00Z ABERDEEN RAOB. THESE MODELS FAVOR SOME LINGERING HIER LIKELY POPS EARLY IN THE EVNG OVER THE SE BEFORE VIGOROUS DRYING BRINGS A CLRG TREND EVEN THOUGH ANOTHER COLD FNT ASSOCIATED WITH SHRTWV NOW DIGGING THRU SCENTRAL CANADA IS PROGGED TO PASS OVERNGT. H85 TEMPS DROPPING TO ARND 0C OVER THE KEWEENAW BY 12Z TUE WL RESULT IN A MUCH COOLER OVERNGT WITH MIN TEMPS DIPPING TO ARND 40 AND PERHAPS THE UPR 30S AT SOME OF THE HIER TERRAIN LOCATIONS. STRONG NW FLOW OVER THE RELATIVELY WARM LK WATERS WL LIMIT THE TEMP DROP. ALTHOUGH THE SFC-H85 DELTA T BTWN THE RELATIVELY WARM LK WATERS /MID TO UPR 50S F/IS SUFFICIENT FOR LK CLDS/PCPN...THE INCOMING AIRMASS WL BE TOO DRY AND THE LLVL FLOW TOO ACYC TO SUPPORT MORE THAN SCT CLDS OVER THE HIER TERRAIN. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 409 AM EDT MON SEP 28 2015 UPPER LEVEL TROUGH FROM HUDSON BAY TO UPPER GREAT LAKES SLIDES TO EASTERN CANADA LATE THIS WEEK WHILE HEIGHTS SLOWLY REBOUND FM NORTHERN PLAINS TO UPPER GREAT LAKES. TROUGH WILL ENSURE A COOLER WEEK WITH FROST/FREEZE OVER PARTS OF CWA TUE NIGHT AND MAYBE WED NIGHT AS WELL. ON TUESDAY...COOLER AIR ARRIVES WITH H85 TEMPS DOWN TO 0C TO -1C BY AFTN. NORTHWEST WINDS COULD BE GUSTY UP TO 25 MPH...ESPECIALLY CLOSER TO LK SUPERIOR. THOUGH APPROACHING HIGH IS THE DOMINANT FACTOR...NAM/GFS/GEM-REGIONAL INDICATE HIGHER H85 RH MOVING ACROSS LK SUPERIOR BY 12Z AND EXPANDING BY 18Z AS THE COOLER AIR ARRIVES. ENVISION FEW-SCT STRATOCU CLOUDS EXPANDING INTO A STRATOCU/CUMULUS DECK MAINLY CNTRL CWA BY AFTN...THEN DIMINISHING THROUGH THE REST OF AFTN. WITH THE CLOUDS AND COLD AIR ADVECTION...TEMPS WILL ONLY REACH LOW TO MID 50S NEAR LK SUPERIOR AND MAY TOUCH 60 DEGREES IN THE FAR SCNTRL. EVEN THOUGH SWIM RISK WILL BE HIGH ALONG MARQUETTE AND ALGER COUNTIES...AIR TEMPERATURES BELOW 55 DEGREES WILL PROHIBIT THE ISSUANCE OF A BEACH HAZARDS STATEMENT. NEXT UP IS TUE NIGHT AND THE FROST/FREEZE POTENTIAL. UPSHOT IS THE FROST/FREEZE POTENTIAL...AT LEAST AWAY FM THE INTERIOR WEST...IS NOT AS CLEAR CUT AS IT LOOKED THE LAST FEW DAYS. RECENTLY IN THE MODELS...IT APPEARED THAT THE APPROACHING HIGH WOULD SETTLE RIGHT OVERHEAD TUESDAY NIGHT. NOW...RIDGE AXIS STAYS MAINLY OVER WESTERN UPR MICHIGAN WHILE A LIGHT BUT PERSISTENT NE LOW-LEVEL FLOW AFFECTS EAST HALF OF CWA /SEE THIS AS 950-900MB WINDS OVER 10 KTS FM NCNTRL INTO EASTERN CWA. ALSO...WITH H85 TEMPS STAYING AROUND -1C OVERNIGHT TUESDAY NIGHT AND MORE OF AN ONSHORE WIND WITH SOME 875MB-850MB MOISTURE SHOWN ON GFS/NAM SOUNDINGS...MAY HAVE TO CONTEND WITH SCT- BKN LAKE EFFECT CLOUDS AS DELTA T VALUES WILL BE OVER 15C. BEST CHANCE FOR BKN CLOUDS WOULD BE OVER FAR NCNTRL UPR MICHIGAN AND ACROSS THE KEWEENAW. ADJUSTED SKY GRIDS TO BUMP UP CLOUD COVER FOR THERE AREAS...ESPECIALLY FOR THE KEWEENAW. FOR TEMPS...USED GUIDANCE THAT SHOWED LOWEST TEMPS IN THE UPR 20S OVER INTERIOR WEST BUT KEPT READINGS MAINLY MID-UPR 30S WHERE CLOUDS MAY DISRUPT COOLING. AFTER A MOSTLY SUNNY BUT COOL DAY ON WED...ANOTHER CHILLY NIGHT WITH SOME FROST SEEMS PROBABLE FOR WED NIGHT. SETUP IS NO BETTER THAN TUE NIGHT THOUGH AS HIGH CENTER IS MORE OVER QUEBEC AND THAT LEAVES A LIGHT EASTERLY FLOW ACROSS UPR MICHIGAN. EVEN SO...MIN TEMPS MAY BE AT LEAST IN LOWER 30S...ESPECIALLY OVER INLAND AREAS. DAYTIME HIGHS WED INTO THU SHOULD STAY IN THE 50S TO AROUND 60 DEGREES. THESE VALUES ARE PRETTY SEASONABLE FOR LATE SEPTEMBER...THOUGH MUCH COOLER THAN THE WELL ABOVE NORMAL TEMPS SEEN MUCH OF THIS MONTH. AFTER SOME RAIN TODAY...DRIER TREND THAT BEGAN TO SHOW UP IN THE MODELS LAST COUPLE DAYS CONTINUES AS HIGH PRESSURE BUILDING IN BEHIND COLD FRONTAL PASSAGE TODAY EXPANDS ACROSS THE UPPER GREAT LAKES ON WED AND BUILDS FURTHER TO OVER 1040MB IN QUEBEC ON FRIDAY. RIDGE FM THE HIGH EXPANDS WESTWARD ACROSS THE UPPER GREAT LAKES AND AS FAR WEST AS SASKATCHEWAN AND MANITOBA. AT FIRST GLANCE...THIS SHOULD KEEP MAJORITY OF REGION DRY THROUGH THE UPCOMING WEEKEND. HOWEVER...GFS AND 12Z ECMWF INDICATE THAT DECENT STRENGTH SHORTWAVE TROUGH BREAKING FREE FM THE LARGER SCALE TROUGH OVER EASTERN CANADA WILL SLIDE OVER UPR GREAT LAKES FRIDAY INTO THE WEEKEND. 00Z ECMWF NOT NEAR AS DEEP WITH TROUGH AS IT SHOWED WITH 12Z RUN THOUGH. DEEP MOISTURE APPEARS SPOTTY BUT THERE ARE HINTS THERE MAY BE ENOUGH FORCING AND MOISTURE TO SUPPORT SOME SHOWERS. OVERALL MOST CWA WILL REMAIN DRY THROUGH NEXT WEEKEND AS UPPER LEVEL TROUGH WILL BE LACKING LOW-LEVEL SUPPORT AS THE SFC HIGH REMAINS THE DOMINANT WEATHER FEATURE. IF THERE ENDS UP BEING BETTER CYCLONIC FLOW IN LOW- LEVELS AS 12Z ECMWF INDICATED...COULD SEE HELP FM LK SUPERIOR FOR PRECIP AS H85 TEMPS ARE FORECAST TO BE AS LOW AS -3C WITH THE UPPER TROUGH OVERHEAD. DAYTIME HIGHS SHOULD SETTLE BACK INTO THE 50S FRIDAY AND SATURDAY WITH THE COOLER TEMPS ALOFT. FINALLY...GFS IS MUCH MORE AGGRESSIVE THAN ECMWF WITH SECONDARY STRONGER SHORTWAVE TROUGH MOVING THROUGH IN MORE TYPICAL NW TO SE PROGRESSION LATE NEXT WEEKEND INTO EARLY NEXT WEEK /DAYS 8-10/. H85 TEMPS AS LOW AS -9C IN THE CORE OF THE COLDEST AIR OVER ONTARIO WITH AROUND -5C OVER UPR MICHIGAN LAST TWO RUNS. NEITHER THE 12Z RUN OR MOST RECENT 00Z RUN OF ECMWF SHOWED ADDITIONAL TROUGHING THOUGH WITH RIDGING RE APPEARING INTO NEXT WEEK IN WAKE OF THE WEEKEND TROUGHING. ECMWF DOES INDICATE TROUGHING AND SIMILAR DEGREE OF COLD AIR...BUT IT STAYS WELL UPSTREAM OVER NORTHWEST CANADA MOST OF THE WEEK. FOR THE FORECAST...CONSENSUS SHOULD COVER IT ATTM. USUALLY DO NOT GET TOO CONCERNED WITH THESE TYPE OF DETAILS IN THE FAR REACHES OF EXTENDED AND BEYOND...BUT GIVEN THE VERY WARM SEPTEMBER ABOUT TO CONCLUDE /POTENTIALLY RECORD WARMEST AT SOME LOCATIONS ACROSS UPR MICHIGAN/...IT IS NOTABLE THAT SOME MODELS ARE HINTING AT COOLER AIRMASSES CLOSE BY AS FIRST FULL WEEK OF OCTOBER ARRIVES. OFFICIAL 8-14 DAY AND EXPERIMENTAL 3-4 WEEK FORECASTS FM CPC STILL INDICATING WARMER THAN NORMAL TEMPERATURES SHOULD PREVAIL OVERALL THROUGH MUCH OF NEXT MONTH. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 201 PM EDT MON SEP 28 2015 A COLD FRONT OVER WRN UPPER MI WILL PASS THRU KSAW IN THE NEXT FEW HRS. A SECONDARY COLD FRONT WILL THEN FOLLOW THIS EVENING AND OVERNIGHT. -SHRA ASSOCIATED WITH THE FIRST COLD FRONT WILL AFFECT KSAW FOR MUCH OF THE AFTN WITH MVFR CONDITIONS LIKELY PREVAILING FOR THE NEXT FEW HRS. TO THE W...INCOMING DRIER AIR HAS ALREADY RESULTED IN LOW CLOUDS CLEARING OUT AT KIWD/KCMX...AND VFR CONDITIONS WILL BE THE RULE AT THOSE TERMINALS THIS AFTN. BEHIND THE SECOND COLD FRONT...NW WINDS WILL INCREASE...ESPECIALLY AT KCMX WHERE WINDS WILL LIKELY GUST TO AROUND 25KT. INCOMING CHILLY AIR MASS WILL BE VERY DRY...SO NOT EXPECTING ANYTHING MORE THAN SCT LAKE EFFECT CLOUDS TO DEVELOP LATE TONIGHT/TUE MORNING...ALLOWING VFR CONDITIONS TO PREVAIL AT KIWD/KCMX/KSAW TONIGHT/TUE. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 419 AM EDT MON SEP 28 2015 SW WINDS UP TO 25 KTS THIS MRNG AHEAD OF A COLD FRONT MOVING THRU WESTERN LAKE SUPERIOR EARLY THIS MORNING WILL SHIFT TO THE W-NW UP TO 20 KTS FOLLOWING THE FRONTAL PASSAGE BY EARLY AFTERNOON OVER THE FAR EAST. ANOTHER COLD FRONT WILL SWING ACROSS THE LAKE TONIGHT. EXPECT NNW WINDS TO INCREASE UP TO 25-30 KTS IN ITS WAKE LATE TONIGHT/TUE. AS A TRAILING HIGH PRESSURE CLOSES IN ON THE AREA ON TUE NIGHT/WED...WINDS WILL DIMINISH TO UNDER 15-20 KTS. ONCE THE HIGH SHIFTS INTO QUEBEC LATER IN THE WEEK...E WINDS UP TO 20 KTS WILL DOMINATE. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...KC LONG TERM...JLA AVIATION...ROLFSON MARINE...KC
AREA FORECAST DISCUSSION...UPDATED
NWS DULUTH MN
1222 PM CDT MON SEP 28 2015 .SHORT TERM...(TODAY THROUGH TUESDAY) ISSUED AT 304 AM CDT MON SEP 28 2015 A WEAK COLD FRONT IS SLOWLY SLIDING SOUTHEAST ACROSS THE FORECAST AREA EARLY THIS MORNING...GENERALLY DRAPED FROM LAKE SUPERIOR SOUTHEAST ACROSS CENTRAL MINNESOTA AND ON INTO SOUTH DAKOTA. SOME SCATTERED SHOWERS ARE AFFECTING NORTHWEST WISCONSIN OUT AHEAD OF IT...BUT NOT BRINGING MUCH IN THE WAY OF PRECIPITATION. SOME FOG HAS FORMED BEHIND THE FRONT...BUT VISIBILITIES ARE STILL IN THE 3-5 MILE RANGE AND DO NOT EXPECT CONDITIONS TO GET MUCH WORSE. THE FRONT WILL CONTINUE TO SLIDE SOUTHEAST THIS MORNING...AND SHOULD BE SOUTHEAST OF THE FORECAST AREA BY MID DAY. OF INTEREST ON SATELLITE IMAGERY THIS MORNING IS A SHORTWAVE MOVING OUT OF WYOMING AND INTO SOUTH DAKOTA...WITH SOME DECENTLY COLD CLOUD TOPS AND A FAIR AMOUNT OF LIGHTNING WITH IT...SOMEWHAT UNUSUAL FOR THIS TIME OF YEAR AND DAY. THUS...EXPECT THAT THIS PARTICULAR FEATURES IS PROBABLY STRONGER THAN MOST OF THE MODELS SHOW...AND EXPECT IT TO CONTINUE TO RIPPLE EAST ALONG THE COLD FRONT DURING THE DAY TODAY. BASED ON THIS STRONGER FEATURE HAVE GONE WITH HIGHER POPS ACROSS MY SOUTHEASTERN CWA DURING THE DAY TODAY...USING THE 06Z HRRR RUN FOR THE GENERAL PLAN AND HAVE MADE SOME OTHER TWEAKS TO PLACE A BAND OF SHOWERS AND ISOLATED THUNDERSTORMS ACROSS MY NW WISCONSIN COUNTIES DURING THE DAYTIME TODAY...GENERALLY FROM 15Z TO 21Z. OTHERWISE...IT SHOULD BE A FAIRLY DECENT DAY WITH HIGHS IN THE 60S MOST LOCATIONS AND LIGHT WINDS. TONIGHT THE FRONT DROPS FAR ENOUGH SOUTH THAT THE RIDGE OF HIGH PRESSURE CAN BUILD INTO THE AREA FOR TONIGHT AND TUESDAY. THIS SHOULD SET US UP FOR A GOOD RADIATIONAL COOLING NIGHT WITH CLEAR OR NEARLY CLEAR SKIES AND COLD TEMPERATURES ALOFT TO ACCOMPANY THE COLD AIRMASS MOVING INTO THE AREA. LATEST GUIDANCE INDICATES THAT WE WILL HAVE SOME 850MB TEMPS IN THE -3 C RANGE BY 12Z. THIS SHOULD SET US UP FOR SOME CHILLY TEMPERATURES TONIGHT...WITH LOWS DIPPING INTO EVEN THE UPPER 20S IN SOME OF OUR COLD SPOTS AND 30S ELSEWHERE. FROST IS A REAL POSSIBILITY. HAVE LEFT IT TO THE DAY SHIFT TO SEND OUT A FROST/FREEZE ADVISORY AS SPECIFIC LOCATIONS ARE STILL SOMEWHAT IN QUESTION...BUT ANTICIPATE THAT WE WILL NEED ONE OR BOTH FOR AT LEAST PARTS OF THE FORECAST AREA. TUESDAY TO REMAIN CHILLY WITH HIGHS ONLY IN THE 50S IN THIS CHILLY AIRMASS...AND THE DRY AIR TO BRING OUR MIN RH VALUES DOWN INTO THE 20 PERCENT RANGE DURING THE AFTERNOON. .LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY) ISSUED AT 304 AM CDT MON SEP 28 2015 LOW CONFIDENCE IN THE PATTERN LATE WEEK INTO THE WEEKEND DUE TO A WIDE RANGE IN MODEL SOLUTIONS...BUT SOME NOTABLE TRENDS ARE BEGINNING TO EMERGE. A COOL TUESDAY NIGHT WITH TEMPERATURES FALLING TO NEAR FREEZING IN SOME LOCATIONS...THEN GENERALLY SEASONABLE TEMPERATURES WITH LOW CHANCES FOR PRECIPITATION THROUGH THE REST OF THE PERIOD. ON THE SYNOPTIC SCALE THE LONG TERM PERIOD BEGINS WITH AN AMPLIFIED RIDGE ACROSS THE INTERMOUNTAIN WEST AND BROAD TROUGH OVER THE SOUTHEAST. AN AREA OF HIGH PRESSURE WILL BE DRIFTING EASTWARD WITH WEST/SOUTHWEST FLOW AT LOW/MID LEVELS DEVELOPING ON WEDNESDAY. AS THIS HIGH DEPARTS TUESDAY NIGHT TEMPS ARE EXPECTED TO FALL TO NEAR FREEZING...MAINLY ACROSS INLAND NORTHWEST WISCONSIN BUT ALSO IN POCKETS ACROSS THE IRON RANGE AND MN ARROWHEAD. AN EMBEDDED SHORTWAVE TROUGH JUST AHEAD OF THE RIDGE AXIS WILL DIVE SOUTHWARD FROM SASKATCHEWAN/MANITOBA INTO THE NORTHERN PLAINS. WHILE THE BEST UPPER LEVEL FORCING WILL BE IN SOUTHERN MANITOBA...WITH WARM AIR ADVECTION AND A FAIRLY DEEP LAYER OF MOISTURE IN PLACE THERE IS A CHANCE FOR SHOWERS LATE WED/WED NIGHT ACROSS NORTHWEST TO EVEN NORTH CENTRAL MINNESOTA...WITH THE BEST CHANCE TOWARDS THE BORDERLAND. WHILE CLOUDS WILL BE PRESENT ACROSS MUCH OF NORTHERN MINNESOTA WEDNESDAY...THEY SHOULD BEGIN TO CLEAR OUT THURSDAY AS EASTERLY LOW LEVEL WINDS PREVAIL DUE TO AN 850/700 MB HIGH OVER ONTARIO. FOR THE WEEKEND GUIDANCE IS ALL OVER THE PLACE WITH THE SYNOPTIC PATTERN...EVEN DISREGARDING THE CANADIAN MODEL WHICH HAS RECENTLY SHOWN POOR RUN TO RUN CONTINUITY. ONE INTERESTING FEATURE ON THE 00Z GFS IS A LOW THAT DROPS OUT OF EASTERN CANADA AND MOVES WESTWARD TOWARDS THE UPPER GREAT LAKES FRIDAY INTO SATURDAY. WHILE THE LATEST ECMWF DOES NOT SHOW THIS AS STRONGLY...PREVIOUS RUNS HAVE DEPICTED SUCH A FEATURE. ONE CONSISTENT FEATURE IS A 850MB HIGH OVER FAR NORTHWEST ONTARIO WHICH COULD BRING AS COLD AS 0C AIR OVER THE UPPER GREAT LAKES THIS WEEKEND. EASTERLY FLOW THIS COLD OVER A RELATIVELY WARM LAKE COULD PRODUCE SOME LAKE EFFECT /RAIN/ SHOWERS...BUT WITH QUESTIONS ABOUT THE UPPER PATTERN THROUGH THIS PERIOD CONFIDENCE REMAINS LOW. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 1220 PM CDT MON SEP 28 2015 VFR CONDITIONS EXPECTED THROUGH THE NEXT 24 HOURS WITH HIGH CLOUDS STREAMING EWD ACROSS THE AREA THIS AFTERNOON AND CLEARING OUT TONIGHT. WINDS WILL BECOME GUSTY FROM THE NW THIS AFTERNOON AROUND 15 TO 20 KTS...AND REMAIN BREEZY FROM THE N/NW TONIGHT AROUND 5 TO 10 KT. && .PRELIMINARY POINT TEMPS/POPS... DLH 69 40 56 37 / 10 0 0 0 INL 62 29 56 33 / 0 0 0 0 BRD 70 38 60 38 / 20 0 0 0 HYR 70 36 59 29 / 60 0 0 0 ASX 70 40 58 34 / 30 0 0 0 && .DLH WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. LS...NONE. && $$ SHORT TERM...LE LONG TERM...JJM AVIATION...TENTINGER
PREVIOUS FORECAST DISCUSSION ALLUDED TO WILL HAVE TO CLOSELY WATCH
FIRE DANGER POTENTIAL IN THIS TIMEFRAME ESPECIALLY IN WESTERN AREAS
WHERE RH SHOULD BE LOWEST AND ANTECEDENT CONDITIONS ARE DRIEST. HOWEVER...GIVEN UNCERTAINTY IN THE DETAILS OF EVOLVING E COAST LOW PRESSURE AND ULTIMATE EFFECTS ON OUR SURFACE WINDS AND AIR MASS...HAVE NOT PUT ANYTHING IN HWO AS OF YET. MODEL LOW LEVEL TEMP FORECASTS SUGGEST MODEL BLENDS ARE TOO WARM FOR LATE WEEK INTO THE WEEKEND. HOWEVER GIVEN FULL SUN AND GENERALLY DRY GROUND EXCEPT OVER FAR EASTERN MS...AM HESITANT TO LOWER MAX TEMPS. HENCE FOR NOW JUST EXPANDED THE DIURNAL RANGES...GOING WITH MODEL GUIDANCE FOR MAXES BUT CUTTING 3-5 DEG FOR MINS ESPECIALLY FRI AND SAT MORNINGS. /AEG/ && .AVIATION... EXPECT MOSTLY MVFR/IFR CONDITIONS TO CONTINUE ACROSS TAF SITES THROUGH THE PERIOD...AS A LARGE AREA OF LOW PRESSURE CENTERED OVER THE NORTHWEST GULF CONTINUES TO ROTATE MOISTURE OVER THE AREA. SHOWERS ARE ALSO POSSIBLE ACROSS THE AREA WITH THE BEST CHANCE AT GTR/MEI AND HBG. THE WINDS WILL REMAIN OUT OF THE NORTHEAST TO EAST AT 5-8KTS THROUGH THE PERIOD./15/ && .PRELIMINARY POINT TEMPS/POPS... JACKSON 70 85 69 84 / 39 36 29 32 MERIDIAN 69 83 67 83 / 66 39 37 36 VICKSBURG 68 85 67 85 / 35 40 27 24 HATTIESBURG 71 87 69 85 / 36 31 21 46 NATCHEZ 68 83 67 84 / 32 35 23 27 GREENVILLE 68 83 68 84 / 36 43 28 19 GREENWOOD 69 83 67 84 / 53 46 33 26 && .JAN WATCHES/WARNINGS/ADVISORIES... MS...NONE. LA...NONE. AR...NONE. && $$ AEG/15
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
332 PM CDT MON SEP 28 2015 .SHORT TERM: (Through Late Tonight) Issued at 330 PM CDT Mon Sep 28 2015 Forecast area continues to get squeezed between upper level shortwave energy that is retrograding back to the north towards forecast area and next cold front moving in from the northwest. Showers currently trying to move into our far southern counties as of 20z. So will initially see isolated/scattered showers develop and advect north into forecast area through this evening and into the overnight hours. In the meantime, cold front will move closer to region from the northwest, but will not see any precipitation from it until after 12z Tuesday, just an increase in cloud cover. Because of this weather pattern, winds will be light and variable. As for overnight lows, once again to remain about 10 degrees above normal, in the low to mid 60s. Byrd .LONG TERM: (Tuesday through Next Monday) Issued at 330 PM CDT Mon Sep 28 2015 FA will remain on the northern fringes of the upper low drifting into the lower Mississippi Valley tomorrow, while upper trof pushing into the upper Great Lakes will allow cold front that approaching northern sections of the FA late tonight to ooze across the region during the day. Some PoPs will be tied to both these features, but I`m really not sure that the 12z based MOS from either the NAM or GFS have a real good handle on the expected precip threat and/or trends. Mass and moisture fields would certainly suggest that southeast sections of the CWA will be on the northern fringes of the precip associated with the southern system on Tuesday, which also suggests that some MOS numbers in this section of the FA may be a bit too high (and this has certainly been the case for the past several days). However, the last few hours of the last several HRRR runs suggest precip blossoming very late tonight as far north to near the I44-I70 corridor...roughly near the northern trofing associated with the upper low. I have upped PoPs some over the southeast half of the CWA, but ultimately expect a pretty sharp PoP gradient that will be resolved in the nowcast time frame. Meanwhile across the north, expect a fairly large band of showers along and especially north of the cold front just north of our FA early Tuesday, with the showers working southeast and gradually diminishing in coverage with time as the cold front works across the region. Some low post-frontal shower threat will likely linger into the evening hours before the drier air behind the front scours out the low level moisture. The latest 12z guidance is continuing the trend of the last few days of being more bullish deepening the UA trof over the eastern CONUS during the latter half of the week, which in turn allows for a stronger intrusion of the Canadian high into the mid-Mississippi Valley. Based on progged 850MB thermal profiles, temperatures will have a decidely autumn feel...with highs dropping into the 60s and lows tumbling into the 40s across the entire region Friday-Sunday. With the high progged to exert greater dominance in the weather over the region, it would appear that precip chances will be fairly low. Specifics in the medium range UA progs are hard to pin down as solutions are noisy and chaotic to say the least...but there does seem to be some agreement that WAA will develop over the Plains Friday night, with associated shower threat possibly working into western/sw portions of the FA Sat-Sun. Truett && .AVIATION: (For the 18z TAFs through 18z Tuesday Afternoon) Issued at 1228 PM CDT Mon Sep 28 2015 Diurnal mvfr cu has developed across the forecast area so will see mvfr cigs for a few hours before lifting to low end vfr by 20z Monday. Otherwise, light and variable winds. Cold front to move into forecast area during the morning on Tuesday, moving through KUIN by 14z and metro area by 17z Tuesday. Will see winds veer to the north behind the front and pickup to between 10 and 15kts and mvfr cigs move in. Precipitation coverage hard to pin down with this boundary, so kept tafs dry for now. On another note, with some low level moisture lingering, could see some patchy fog towards daybreak on Tuesday in the river valleys, so may need to add mention in later tafs at KSUS and KCPS. Specifics for KSTL: Diurnal mvfr cu has developed across the forecast area so will see mvfr cigs for a few hours before lifting to low end vfr by 20z Monday. Otherwise, light and variable winds. Cold front to move into metro area by 17z Tuesday. Will see winds veer to the north behind the front and pickup to between 10 and 15kts and mvfr cigs move in. Precipitation coverage hard to pin down with this boundary, so kept taf dry for now. On another note, with some low level moisture lingering, could see some patchy fog towards daybreak on Tuesday in the river valleys, so may need to add mention in later tafs at KSUS and KCPS. Byrd && .PRELIMINARY POINT TEMPS/POPS: Saint Louis 67 81 56 73 / 20 30 20 5 Quincy 62 74 48 68 / 10 30 10 5 Columbia 62 80 52 72 / 10 30 20 5 Jefferson City 61 81 55 72 / 10 30 20 5 Salem 65 78 57 72 / 30 40 20 5 Farmington 63 76 56 71 / 30 40 20 5 && .LSX WATCHES/WARNINGS/ADVISORIES: MO...NONE. IL...NONE. && $$ WFO LSX
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
322 PM CDT MON SEP 28 2015 .SYNOPSIS... ISSUED AT 320 PM CDT MON SEP 28 2015 LARGE UPPER LOW OVER THE HUDSON BAY REGION WITH SEVERAL PV ANOMALIES ROTATING AROUND IT. IN ADDITION...POSITIVELY TILTED UPPER LOW OVER THE E PAC WITH AN UPPER LEVEL PV CONNECTION TO THE UPPER LOW OVER THE HUDSON BAY. CLOSER TO HOME...WEAKER PV ANOMALY MOVING ACROSS SRN WY ATTM GENERATING SHRA AND ISOLD TSRA ACROSS ERN WY...WITH ISOLD SHRA/-TSRA IN PORTIONS OF NC NEBR ASSOCIATED WITH WEAKENING MID LEVEL FGEN ACROSS THAT AREA. SFC FRONTAL BOUNDARY NEARLY STALLED FROM NEAR LIMON CO TO NORTH OF GLD TO JUST S OF EAR TO S OF YANKTON SD. && .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 320 PM CDT MON SEP 28 2015 NEW COLD FRONTAL BOUNDARY WILL SLOWLY PUSH SWD OVERNIGHT WITH MOST OF WESTERN AND NC NEBR REMAINING IN THE POST FRONTAL UPSLOPE FLOW LATE TONIGHT INTO EARLY TUESDAY. THIS WILL BE ATTENDANT TO A EWD ADVANCING PV ANOMALY AS MENTIONED WHICH WILL MOVE ACROSS SRN SD/NRN NEBR THROUGH THE NIGHT. SOME MID LEVEL INSTABILITY PRESENT OVERNIGHT BUT UNCERTAINTY IN COVERAGE AREA AS ISENTROPIC LIFT REMAINS PRESENT ON THE 305/310K LEVELS. ELEVATED WEAK TSRA DEVELOPMENT IN THE LAST HOUR ACROSS BROWN...ROCK AND HOLT COUNTIES STILL ASSOCIATED WITH MID LEVEL FGEN WITHIN AN AREA OF MID LEVEL INSTABILITY. INTEGRATING THE VARIOUS SOLUTIONS OVERNIGHT YIELDS AN AREA OF SHRA AND TSRA CURRENTLY OVER SWRN SD TO MOVE ACROSS NRN NEBR BUT THEN SOME MODELS SUGGEST AN AREA OF MID LEVEL FGEN ACROSS CENTRAL NEBRASKA IN THE 06- 09Z TIME FRAME THAT MAY ALLOW REDEVELOPMENT WWD. MEANWHILE THE HRRR SUGGESTS DEVELOPMENT WITH THE SWD ADVANCING FRONT PRIOR TO 06Z AND THEN PUSHING SEWD OVERNIGHT. WITH SEVERAL SMALL SHORT WAVES MOVING THROUGH THE AREA TIMING AND LOCATION OF NEW DEVELOPMENT BECOMES DIFFICULT. HAVE THEREFORE INCLUDED CHANCE POPS MOST LOCATIONS THROUGH THE NIGHT. IN ADDITION TO THE PRECIP...LOW LEVEL UPSLOPE FLOW SHOULD ALLOW FOR DEVELOPMENT OF STRATUS AND AT LEAST PATCHY FOG AFTER MIDNIGHT...THOUGH WINDS ARE CURRENTLY STRONGER THAN WOULD BE FAVORABLE FOR WIDESPREAD LOW VSBYS. HENCE HAVE SIDED ON PATCHY FOG MENTION. ISENTROPIC LIFT CONTINUES OFF AND ON THROUGHOUT THE DAY TUESDAY SO WOULD EXPECT OCCASIONAL REDEVELOPMENT OF SHRA ESPECIALLY IN SWRN NEBR. TEMPS WILL BE HELD DOWN CONSIDERABLY DUE TO LOW CLOUD COVER AND ANY PRECIP THAT DOES DEVELOP. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 320 PM CDT MON SEP 28 2015 MODELS AGAIN COMING IN COOLER. HAVE USED A BLEND OF THE GFS AND NAM FOR THE MID TERM AND GFS AND ECMWF FOR THE LONG TERM. TOMORROW NIGHT UPSLOPE FLOW THROUGH THE PANHANDLE AND SOUTHWEST NEBRASKA WITH A STATIONARY BOUNDARY TO THE WEST SEVERAL WEAK WAVES MOVING THROUGH RIDGE. ISOLATED THUNDER ALONG THE BOUNDARY WITH LLJ AND SOME LIFT. ISOLATED RAINSHOWERS CONTINUING THROUGH THE MORNING WITH DRIZZLE TO THE EAST LATE AFTERNOON INTO THE EVENING. COOLER AIR FILTERING INTO WESTERN NEBRASKA THURSDAY NIGHT THROUGH THE WEEKEND. ECMWF WARMER THAN GFS. STRONG WAVE MOVING OUT OF THE ROCKIES WITH SHARP GRADIENT OVER THE NEBRASKA PANHANDLE. COOL AT THE SURFACE WITH INSTABILITY ALOFT AS WARNER AIR AT THE SURFACE TO THE SOUTH LIFTED OVER THE COOLER AIR. STRONG LOW LEVEL JET OVER NIGHT WITH THUNDERSTORMS LIKELY. TRANSITIONING TO RAINSHOWERS THROUGH THE DAY ON FRIDAY AND CONTINUING THROUGH SATURDAY NIGHT AS UPPER LOW MOVES EAST AND BECOMES NEGATIVELY TILTED. SHOWERS END SUNDAY WITH A WARMUP INTO MONDAY. TEMPERATURES IN THE 60S EAST AND 70S WEST WEDNESDAY AND THURSDAY AND THEN COOLER AIR FOR FRIDAY AND SATURDAY WITH TEMPERATURES IN THE 50S. 50S AND 60S SUNDAY. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 109 PM CDT MON SEP 28 2015 VFR CONDITIONS ARE EXPECTED TO PREVAIL ACROSS THE KLBF AND KVTN TERMINALS UP UNTIL THE 06Z HOUR...HOWEVER...RAIN SHOWERS WILL BE POSSIBLE THROUGH THE 23Z-04Z WHICH COULD LOWER CEILINGS TEMPORARILY TO MVFR. THESE RAIN SHOWERS WILL BE SUPPORTED BY WEAK UPPER LEVEL FORCING AND A SLOWLY SAGGING COLD FRONT ACROSS WESTERN AND NORTH CENTRAL NEBRASKA...WHICH IS REPRESENTED FAIRLY WELL BY CURRENT SHORT TERM MODELS. WINDS PRIOR TO THE 06Z HOUR...ESPECIALLY WITHIN THE KLBF TERMINAL...WILL BE BREEZY FROM THE NORTHEAST. THE FORECAST AFTER 06Z THEN BECOMES TRICKY...AS VARYING SOLUTIONS ARE CURRENTLY BEING PROPOSED BY THE NAM/GFS/RAP/SREF MODELS. THE MAJOR UNCERTAINTY THAT ARISES FROM THE VARYING MODELING SOLUTIONS IS BOTH AREAL COVERAGE OF THE LOWER CEILINGS...IN ADDITION TO THE MAGNITUDE OF THE LOWER CEILINGS. THE CURRENT 12Z NAM SOLUTION IS THE MOST AGGRESSIVE IN AREAL COVERAGE AND MAGNITUDE OF THE LOWER CEILINGS... THE 12Z GFS IS THEN CONSIDERABLY DRIER IN NATURE...WITH THE RAP BEING A MIDDLE OF THE ROAD SOLUTION WITH RESPECT TO THESE CEILINGS. HAVE DECIDED TO SIDE WITH THE NAM SOLUTION WITH RESPECT TO THE KLBF TERMINAL AFTER 06Z...AS THE KLBF TERMINAL WILL BE IN CLOSEST PROXIMITY TO THE COLD FRONT. HAVE THEN SIDED WITH MORE OF A GFS/RAP SOLUTION FOR KVTN...AS THE AFOREMENTIONED COLD FRONT WILL BE DISPLACED FAR ENOUGH TO THE SOUTH...LIMITING THE AMOUNT OF STRATUS. AT THIS TIME...NOT THINKING THAT FOG WILL BE A PROBLEM AT EITHER THE KLBF AND KVTN TERMINALS...AS WINDS WILL REMAIN ABOVE MINIMUM THRESHOLDS CONDUCIVE TO THE FORMATION OF FOG. && .LBF WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...JWS SHORT TERM...JWS LONG TERM...POWER AVIATION...MOLDAN
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
135 PM EDT MON SEP 28 2015 .SYNOPSIS... SHOWERS WILL BE POSSIBLE TODAY, MAINLY OVER THE FINGER LAKES AND CENTRAL NEW YORK. SHOWERS WILL BECOME MORE LIKELY ON TUESDAY INTO WEDNESDAY, AS A COLD FRONT PUSHES INTO THE REGION. && .NEAR TERM /THROUGH TONIGHT/... 1130 AM UPDATE... THE CURRENT FORECAST FOR THIS AFTERNOON INTO THE EVENING STILL LOOKS REASONABLE, WITH JUST MINOR TWEAKS REQUIRED AT THIS TIME. SCATTERED SHOWERS WILL CONTINUE TO BE SEEN OVER OUR WESTERN AND NORTHERN ZONES, AS THE BEST MOISTURE FEED IS IN THIS AREA, AROUND THE OUTER PERIPHERY OF THE SLOWLY DEPARTING LOW-LEVEL RIDGE. LITTLE OR NO PRECIPITATION IS ANTICIPATED OVER THE NEAR-TERM, ALONG AND EAST OF THE I-81 CORRIDOR. DESPITE ABUNDANT CLOUD COVER, A MILD AIR MASS, ALONG WITH FURTHER LOW-LEVEL WARM ADVECTION, WILL STILL BRING HIGHS INTO THE 70S OVER MANY AREAS THIS AFTERNOON. PREVIOUS DISCUSSION... 400 AM UPDATE... AFTER GETTING LUCKY FOR MOST OF THE AREA LAST NIGHT BEING CLEAR ENOUGH TO VIEW THE ECLIPSE, REALITY IS SETTING IN WITH THICK CLOUDS ON OUR DOORSTEPS WITH SOME SHOWERS NOT FAR BEHIND. FOLLOWED LATEST HRRR QPF FIELDS AND INCREASED TO LIKELY POPS THROUGH MID MORNING FROM THE WESTERN SOUTHERN TIER UP THROUGH FINGER LAKES. PRECIP SHOULD MAKE IT TO CNY BUT MAY BREAK UP A BIT BY THE TIME THAT HAPPENS. LATER TODAY AND THROUGH TONIGHT RAIN CHANCES DON`T LOOK ALL THAT GREAT BUT WE CAN`T RULE ANYTHING OUT, ESPECIALLY IN PRETTY MUCH THE SAME AREAS JUST MENTIONED ABOVE. FARTHER SOUTH ESPECIALLY INTO PA, MAINLY DRY WEATHER IS EXPECTED. && .SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... 4 AM UPDATE... ALTHOUGH MY GARDEN IS WINDING DOWN DUE TO THE LOSS OF DAYLIGHT/LOW SUN ANGLE, I AM GETTING EXCITED ABOUT THE POSSIBILITY OF SOME RAIN AROUND HERE! RAIN CHANCES GO UP FOR OUR AREA BY TUESDAY AFTERNOON AS A COLD FRONT APPROACHES. CONTINUE TO MENTION SOME ISOLATED THUNDER THROUGH EARLY TUESDAY NIGHT TO MATCH WELL WITH OTHER OFFICES ALONG WITH THE FACT LI`S ARE NEAR OR BELOW ZERO. UNLIKE PAST RAIN EVENTS WITH EACH MODEL RUN WE ARE LOOKING AT INCREASING CHANCES FOR HIGHER RAINFALL AMOUNTS INSTEAD OF LOWER ONES. IN FACT THE MAIN TREND OF THE 0Z RUNS OF BOTH THE EURO AND GFS NOT ONLY RAISE RAINFALL AMOUNTS, THE PROGRESSION OF THE COLD FRONT THROUGH OUR AREA IS MUCH SLOWER. ACCORDINGLY I RAISED POPS ABOVE 70% FOR THE ENTIRE AREA TUESDAY NIGHT. IN FACT THROUGH MUCH OF WEDNESDAY NOW, WE HAVE POPS ABOVE 60% FROM NEAR BINGHAMTON SOUTH AND EAST. DRIER WEATHER NOW HOLDS OFF UNTIL WED NIGHT. AT EARLY LOOK AT TOTAL RAINFALL AMOUNTS WOULD BE A HALF OF AN INCH UP ACROSS THE FINGER LAKES, BUT EXCEEDING AN INCH FROM NEAR BINGHAMTON SOUTH AND EAST, WHERE PRECIP LINGERS THE LONGEST. && .LONG TERM /THURSDAY THROUGH MONDAY/... 200 PM SUNDAY UPDATE... THOUGH DIFFERING ON DETAILS...MODELS ARE STARTING TO GET INTO BETTER LARGE SCALE AGREEMENT...ON THE IDEA OF AN UNSETTLED TROUGHY PATTERN TAKING SHAPE BY NEXT WEEKEND. ONSHORE FLOW...CUTOFF LOW EVOLUTION...AS WELL AS POTENTIAL COASTAL SURFACE LOW...MAY ALLOW MOISTURE TO START CREEPING IN AS EARLY AS FRIDAY AFTERNOON- NIGHT...BUT THE END RESULT DOES APPEAR TO BE COOL AND WET PERIODS INTO NEXT WEEKEND. BEFORE THEN...MAINLY DRY WITH TEMPERATURES SLIGHTLY BELOW CLIMATOLOGY THANKS TO FEED OF AIR FROM SURFACE HIGH PRESSURE IN QUEBEC. A FRONTAL ZONE WILL BE STALLED OUT NOT TOO FAR SOUTHEAST OF US...SO THAT WILL NEED TO BE MONITORED...BUT KEEPING FORECAST GENERALLY DRY FOR NOW WEDNESDAY NIGHT THROUGH THURSDAY NIGHT. && .AVIATION /18Z MONDAY THROUGH SATURDAY/... MARINE LAYER WITH LOW LEVEL S/SE FLOW WILL CONTINUE TO RESULT IN FAIRLY LOW CIGS THROUGH THE TAF PERIOD. CIGS GENERALLY RISE TO LOW END VFR THIS AFTERNOON BUT THEN DROP AGAIN TO MVFR THIS EVENING. LATE TONIGHT INTO TUESDAY MORNING IFR WILL EVEN BE POSSIBLE AT TIMES...ESPECIALLY FOR KITH/KBGM/KAVP. NOT EXPECTING MUCH OF A RISE IN CIGS FOR TUESDAY WITH SHOWERS MOVING IN BY MID TO LATE MORNING AND HEAVIER PRECIP ARRIVING BEYOND THE TAF PERIOD. EXPECT WINDS GENERALLY S/SE AROUND 5 TO 10 KNOTS THROUGH THE TAF PERIOD. .OUTLOOK... TUES AFT-TUES NGT...SHOWERS, HEAVY AT TIMES, WITH ASSOCIATED RESTRICTIONS. WEDNESDAY...CONTINUING SHOWERS AND ASSOCIATED RESTRICTIONS LIKELY. THURSDAY - SATURDAY...BRIEF RESPITE IN UNSETTLED CONDITIONS POSSIBLE THURSDAY BEFORE MORE RAIN/SHOWERS AND ASSOCIATED RESTRICTIONS ARRIVE BY LATE FRIDAY INTO SATURDAY. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...NONE. NY...NONE. && $$ SYNOPSIS...HEDEN NEAR TERM...HEDEN/MLJ SHORT TERM...HEDEN LONG TERM...MDP AVIATION...PCF
AREA FORECAST DISCUSSION
NWS RALEIGH NC
149 PM EDT MON SEP 28 2015 .SYNOPSIS...DEEP ATLANTIC MOISTURE WILL CONTINUE TO PUMP INTO THE REGION TODAY... BETWEEN CANADIAN HIGH PRESSURE TO OUR NORTHEAST AND LOW PRESSURE JUST OFF THE SOUTHEAST COAST. THESE FEATURES WILL WEAKEN TONIGHT INTO TUESDAY... RESULTING IN A BRIEF IMPROVEMENT IN WEATHER CONDITIONS... HOWEVER A SURGE OF GULF MOISTURE AHEAD OF AN APPROACHING COLD FRONT WILL BRING A RETURN TO WET AND UNSETTLED WEATHER LATE TUESDAY THROUGH THURSDAY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 1030 AM MONDAY... NO MAJOR CHANGES TO THE FORECAST THIS MORNING. VERY MOIST AIR MASS REMAINS IN PLACE OVER THE REGION...WITH PWAT VALUES NEAR 2 INCHES PER THE BLENDED TPW IMAGERY. A WEAK WAVE IS PROGGED TO TRACK NORTHEASTWARD OVER EASTERN NC THIS AFTERNOON AND GIVEN SOME WEAK DESTABILIZATION (ALREADY SEEING THIS ACROSS EASTERN NC PER THE SPC MESOSCALE ANALYSIS)...PRECIP CHANCES WILL INCREASE THROUGH THE LATE MORNING/EARLY AFTERNOON HOURS FROM EAST TO WEST (FOLLOWED THE HRRR CLOSELY FOR THE TIMING). THIS AREA OF RAIN/SHOWERS SHOULD GRADUALLY TRANSLATE ACROSS THE FORECAST AREA...WITH THE COASTAL PLAIN SEEING THE BEST CHANCE OF RAIN IN THE NEXT FEW HOURS AND FURTHER WEST BY MID/LATE AFTERNOON. PRECIP SHOULD DIMINISH THROUGH THE EVENING HOURS...BUT LIGHT RAIN/DRIZZLE WILL BE POSSIBLE OVERNIGHT (AS HAS BEEN THE CASE THE LAST SEVERAL DAYS). PREVIOUS DISCUSSION AS OF 3 AM...COLUMN REMAINS VERY MOIST THIS MORNING... ALTHOUGH THE EXTENT OF MOISTURE THROUGH THE COLUMN IS NOT QUITE WHAT IT`S BEEN THE LAST COUPLE OF DAYS. WE`RE IN GRADUAL TRANSITION AWAY FROM THE DYING WEDGE REGIME TO AN ATYPICALLY HUMID (ESP FOR LATE SEPTEMBER) AIR MASS. THE PARENT HIGH WHICH BROUGHT THE DAMMING OVER THE WEEKEND IS NOW CENTERED WELL OUT OVER THE NW ATLANTIC YET STILL NOSING WEST AND SW INTO THE WRN CAROLINAS. THE STABLE POOL OVER THE WRN PIEDMONT HAS WEAKENED... AND THE AIR MASS HAS BECOME MORE HOMOGENEOUS ACROSS THE CWA... DEMONSTRATED BY TEMP/DEWPOINT RANGES OF JUST AROUND 4 DEGREES ACROSS CENTRAL NC... AND UNIFORM OBSERVED LIFTED INDICES AND CINH. MUCH OF THIS PAST EVENING`S LIGHT PRECIP DRIVEN BY ISENTROPIC UPGLIDE HAS SHIFTED WELL NW OUT OF THE AREA... LEAVING JUST WIDESPREAD STRATUS AND PERHAPS A FEW ISOLATED DRIZZLE PATCHES. THIS RELATIVE LULL IN PRECIP WILL CONTINUE THROUGH THE MID MORNING HOURS... HOWEVER AREAS OF SHOWERS NOW JUST OFF THE NC COAST ARE ON TRACK TO TRANSLATE WEST OR WNW INTO THE COASTAL PLAIN AND THEN INTO THE PIEDMONT FROM MID/LATE MORNING THROUGH THE AFTERNOON... WITH COVERAGE FILLING IN AS HEATING ALLOWS FOR A FEW HOLES IN THE CLOUDS AND SUBSEQUENT (WEAK) DESTABILIZATION... WITH LIFT POTENTIALLY AUGMENTED BY A WEAK WAVE TRACKING NE OVER ERN NC THIS AFTERNOON. EXPECT LOW POPS THIS MORNING... TRENDING UP TO LIKELY EAST AND CHANCE WEST... WITH HIGHER POPS THEN PUSHING WNW INTO THE WRN PIEDMONT AS WE GET INTO THE EVENING HOURS... A PATTERN SUGGESTED BY RECENT RUNS OF BOTH LARGE SCALE AND CONVECTION ALLOWING MODELS INCLUDING THE SREF/GFS/3 KM NAMRR AND THE LATEST HRRR RUNS. FORECAST SOUNDINGS SHOW A DEEP WARM LAYER THIS AFTERNOON WITH AN LCL-TO-FREEZING-LEVEL DEPTH OVER 4 KM... ALONG WITH PW VALUES OF 2.0-2.3 INCHES... SO ANY SHOWERS FORMING TODAY WILL BE CAPABLE OF DROPPING BRIEF HEAVY RAIN. FORECAST MUCAPE FOR TODAY IS UNIMPRESSIVE (UNDER 1000 J/KG... MOST OF WHICH IS BELOW THE -10C LEVEL) WITH GENERALLY SUB-20-KT DEEP LAYER BULK SHEAR... SO WILL NOT MENTION THUNDER AT THIS TIME... ALTHOUGH A STRIKE OR TWO IS CERTAINLY POSSIBLE IN THE COASTAL PLAIN. EXPECT THE AREA OF BETTER SHOWER COVERAGE TO CONTINUE SHIFTING WNW TOWARD THE FOOTHILLS DURING THE EVENING... SO WILL TREND POPS DOWN FROM EAST TO WEST TONIGHT... RESULTING IN 30-40% CHANCES NORTHWEST TRANSITIONING DOWN TO JUST ISOLATED SHOWERS EAST OF HIGHWAY 1 OVERNIGHT. STRATUS REDEVELOPMENT APPEARS LIKELY LATE TONIGHT GIVEN THE LOW LEVEL MOISTURE AND TRAJECTORIES ALONG WITH PERSISTENCE... ALTHOUGH A LIGHT BREEZE FROM THE NE -- AS MODELS SUGGEST -- MAY INHIBIT FOG DEVELOPMENT. WILL LEAVE IN A MENTION OF PATCHY FOG FOR NOW. EXPECT HIGHS FROM THE MID 70S NW (WHERE THE AIR IS STILL A BIT MORE STABLE AND MORE RESISTANT TO MIXING AND THUS SHOULD SEE LESS SUNSHINE) TO AROUND 80-82 EAST OF HIGHWAY 1... WITH MOSTLY CLOUDY SKIES. MILD LOWS TONIGHT OF 67-71... AROUND 10 DEG ABOVE NORMAL. -GIH && .SHORT TERM /TUESDAY THROUGH TUESDAY NIGHT/... AS OF 330 AM MONDAY... CONTINUED MOIST WITH A GOOD CHANCE OF SHOWERS... AND PERHAPS A STORM OR TWO. THE MID LEVEL TROUGH FROM THE LOWER GREAT LAKES THROUGH THE LOWER MISS VALLEY TO LA WILL CONTINUE TO TILT SLOWLY... RESULTING IN A GRADUAL INCREASE IN MID LEVEL VORTICITY MOVING FROM THE NW GULF INTO THE CAROLINAS ON WEAK SOUTHWESTERLY MID LEVEL FLOW. THE LOW LEVEL ATLANTIC INFLOW SHOULD BE ON THE DECREASE WITH A REDUCED FETCH... A FUNCTION OF WHAT IS NOW TD #11 AS IT PUSHES SLOWLY NW/NNW ON ITS ANTICIPATED TRACK TOWARD THE OFFSHORE WATERS OF NC. PW IS PROJECTED TO REMAIN VERY HIGH AT 2.0-2.3 INCHES... WELL ABOVE SEASONAL NORMALS... AND MODELS SHOW SLIGHTLY BETTER POTENTIAL FOR INSTABILITY TUE AFTERNOON WITHIN PERSISTENT HIGH THETA-E ADVECTION IN THE LOW LEVELS. DESPITE THE WEAK WIND FIELD AND MARGINAL DPVA... WE SHOULD SEE DECENT UPPER DIVERGENCE OVER THE AREA IN THE LEFT EXIT REGION OF THE BROAD JET FROM THE GULF INTO THE TN VALLEY. WILL TREND POPS UP TO LIKELY OVER MUCH OF THE CWA BY AFTERNOON... WANING GRADUALLY IN THE EVENING/NIGHTTIME BUT STAYING AT 30-50%... WITH BETTER SHOWER CHANCES SHIFTING WNW INTO THE NW PIEDMONT AND FOOTHILLS WITH TIME. SLIGHTLY BETTER CAPE AND SHEAR ARE EXPECTED... STILL MARGINAL THOUGH... SO HAVE INCLUDED JUST A MENTION OF ISOLATED THUNDER IN THE AFTERNOON. HIGHS 75-83 AND LOWS 66-71... BOTH ABOVE NORMAL... WITH MOSTLY CLOUDY SKIES HOLDING FIRM. -GIH && .LONG TERM /WEDNESDAY THROUGH SUNDAY/... AS OF 327 AM MONDAY... UNCERTAINTY IN THE FORECAST IS ABOUT AS HIGH AS CAN BE ADVERTISED FROM MID WEEK INTO THE WEEKEND. THE OPERATIONAL MODELS CONTINUE TO SHOW PLENTY OF SPREAD AND EVEN THE ENSEMBLE MEANS ARE CONFLICTING ON THE PLACEMENT OF THE IMPORTANT WEATHER PRODUCING SYSTEMS. THE MAIN WEATHER HAZARDS SHOULD BE LIMITED TO A LOW END HEAVY RAIN THREAT... BUT SIGNIFICANT RAINFALL MAY BE MORE OF A HELP TO CURRENT DROUGHT STATUS THAN IT WOULD BE A THREAT FOR FLOODING. THE QPF MID TO LATE WEEK IS THE MAIN QUESTION AS ABOUT 30 PERCENT OF THE MODELS INDICATE THE HEAVIEST RAIN INLAND WITH OVERRUNNING RAINS AGAIN THU NIGHT INTO SATURDAY... WHICH 70 PERCENT OF THE MODELS SUPPORT THE HEAVY SWATH OF QPF ALONG OR JUST OFF THE MID-ATLANTIC COAST. ONE THING SEEMS TO BE MORE CERTAIN SHOULD BE THE COOLER TEMPERATURES AGAIN AS ANOTHER STRONG SURFACE HIGH IS EXPECTED TO BUILD SOUTH INTO NC/SC THURSDAY INTO THE WEEKEND. THIS OCCURS AS A TROUGH ALOFT AND LINGERING LOW LEVEL BOUNDARY CONTINUE TO BE FORECAST BY MOST MODELS TO BRING A CONTINUATION OF THE UNSETTLED PATTERN THAT BEGAN LATE LAST WEEK. A RETURN TO A PROLONGED NE FLOW... CONSIDERABLE CLOUDINESS... AND POSSIBLY SIGNIFICANT RAIN IS EXPECTED THU-SAT. && .AVIATION /18Z MONDAY THROUGH SATURDAY/... AS OF 145 PM MONDAY... ADVERSE AVIATION CONDITIONS ARE EXPECTED TO PERSIST THROUGH THE CURRENT TAF PERIOD AS A VERY MOIST AIR MASS REMAINS ENTRENCHED OVER THE REGION. THERE COULD BE A BRIEF IMPROVEMENT TO VFR THIS AFTERNOON...MAINLY ACROSS THE EAST (KRDU/KFAY/KRWI)...WHILE THE TRIAD (KGSO/KINT) MAY IMPROVE SOME FROM THEIR CURRENT IFR STATE... BUT ONLY TO MVFR. SCATTERED SHOWERS ARE POSSIBLE THIS AFTERNOON AND EVENING AND THESE COULD PRODUCE A BRIEF PERIOD OF SUB-VFR VSBYS. PRECIP WILL DECREASE DURING THE OVERNIGHT HOURS...BUT LIGHT RAIN AND/OR DRIZZLE WILL BE POSSIBLE ALL NIGHT. ALL SITES ARE EXPECTED TO DETERIORATE ONCE AGAIN LATER THIS EVENING AND THEN PERSIST ALL NIGHT...WITH POTENTIAL IFR/LIFR CIGS/VSBYS FORMING OVERNIGHT. TUESDAY WILL BE SIMILAR TO TODAY...AS CONDITIONS WILL SLOWLY IMPROVE THROUGH THE EARLY AFTERNOON HOURS...WITH KRDU/KRWI/KFAY LIFTING TO MVFR THEN PERHAPS LOW-END VFR AND KINT/KGSO LIKELY STAYING MVFR THROUGH TUESDAY AFTERNOON. -KRD OUTLOOK...IFR/LIFR CONDITIONS IN FOG ARE EXPECTED TO RETURN ONE AGAIN LATE TUE EVENING THROUGH DAYBREAK WED. VFR CONDITIONS SHOULD RETURN FOR MIDDAY WED BUT SHOWERS/STORMS AHEAD OF A COLD FRONT MAY BRING SUB-VFR CONDITIONS WED/WED NIGHT. THIS FRONT WILL MOVE THROUGH WED NIGHT AND STALL TO OUR SE INTO THE EARLY WEEKEND...POTENTIALLY BRINGING A RETURN TO PREDOMINANTLY POOR AVIATION CONDITIONS WITHIN AREAS OF RAIN/DRIZZLE. -GIH && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...HARTFIELD NEAR TERM...KRD/HARTFIELD SHORT TERM...HARTFIELD LONG TERM...BADGETT AVIATION...KRD/HARTFIELD