Forecast Discussions mentioning any of "HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 03/12/14


AREA FORECAST DISCUSSION
NWS JACKSONVILLE FL
840 PM EDT TUE MAR 11 2014 .UPDATE...APPROACH OF UPPER TROUGH ALONG THE CENTRAL GULF COAST WILL MOVE EAST AND WEAKEN AS IT REACHES NE FL/SE GA AROUND 12Z WED. RUC MODEL SHOWS RAIN REACHING WESTERN ZONES AROUND 04Z... SPREADING EASTWARD TO THE EAST COAST AROUND 08Z. ISOLATED THUNDER WILL BE POSSIBLE AFTER MIDNIGHT INTO EARLY WEDNESDAY MORNING AS WEAK ELEVATED INSTABILITY DEVELOPS AS SHOWN BY MODEL SOUNDINGS. LOW LEVEL JET WILL INCREASE TO 35 TO 40 KTS AFTER 06Z WITH WARM AND WINDY CONDITIONS EXPECTED ON WEDNESDAY POSSIBLY REQUIRING A LAKE WIND ADVISORY. && .AVIATION... LIGHT RAIN WILL MOVE ACROSS THE AREA DURING THE EARLY MORNING HOURS. THE LATEST MOS GUIDANCE STILL CALLS FOR CEILINGS TO ACTUALLY DROP INTO THE IFR CATEGORY AT ALL AREA TERMINALS LATE TONIGHT...BUT MODEL SOUNDINGS AND THE HRRR FORECAST DO NOT SUPPORT THIS. DUE TO THE LACK OF CONFIDENCE WE WILL MAINTAIN A VFR CEILING AND VISIBILITY FORECAST WITH THE LIGHT RAIN EVENT LATE TONIGHT. HAVE ALSO ADDED LLWS TO ALL TERMINALS LATE TONIGHT TO ACCOUNT FOR STRONG SOUTHWEST WINDS JUST ABOVE THE SURFACE INVERSION. RAIN WILL WIND DOWN WEDNESDAY MORNING AND WINDY CONDITIONS WILL DEVELOP WITH SUSTAINED WINDS OF 20 TO 25 MPH AND GUSTS OVER 30 MPH EXPECTED DURING THE DAY. && .MARINE... SOUTHERLY WINDS OF 10 TO 15 KNOTS WILL VEER TO THE SOUTHWEST AND INCREASE TO 15 KNOTS OVERNIGHT. WINDS ARE STILL ON TRACK TO REACH SMALL CRAFT ADVISORY CONDITIONS OVER THE OFFSHORE ZONES DURING THE DAY ON WEDNESDAY. STRONG GUSTY WINDS OVER THE LAND AREAS MAY ALSO REQUIRE THAT WE EXPAND THE CURRENT SMALL CRAFT ADVISORY TO ALSO INCLUDE THE NEARSHORE WATERS. WILL LET THE MIDNIGHT SHIFT MAKE THE FINAL DECISION ON THIS. && .PRELIMINARY POINT TEMPS/POPS... AMG 58 79 37 59 / 70 60 20 0 SSI 61 77 42 56 / 70 60 20 0 JAX 58 82 41 60 / 60 50 20 0 SGJ 62 80 45 57 / 40 50 20 0 GNV 57 81 42 62 / 60 50 20 0 OCF 59 81 44 63 / 50 50 30 10 && .JAX WATCHES/WARNINGS/ADVISORIES... FL...NONE. GA...NONE. AM...SMALL CRAFT ADVISORY FROM 1 PM WEDNESDAY TO 4 PM EDT THURSDAY FOR ALTAMAHA SOUND GA TO FERNANDINA BEACH FL 20 NM TO 60 NM OFFSHORE-FERNANDINA BEACH TO ST AUGUSTINE FL 20 NM TO 60 NM OFFSHORE-ST AUGUSTINE TO FLAGLER BEACH FL 20 NM TO 60 NM OFFSHORE. && $$ ZIBURA/SHULER/GUILLET
AREA FORECAST DISCUSSION
NWS JACKSONVILLE FL
1049 AM EDT MON MAR 10 2014 ...WARMER TODAY WITH PASSING CLOUDS OVER FL ZONES... .UPDATE... SURFACE HIGH PRESSURE EXTENDING OVER THE EASTERN GULF COAST REGION CONTINUED TO DOMINATE THE LOCAL WEATHER REGIME KEEPING TROUGHING WELL NNE OF THE AREA. A MID LEVEL SHORT WAVE TROUGH NOTED BY AN EXPANSIVE AREA OF STRATOCUMULUS CLOUDS OVER THE EASTERN GULF WILL BRING PERIODS OF CLOUDINESS TO PORTIONS OF OUR FL ZONES TODAY AS IT DRIFTS ESE THROUGH THE PERIOD...AND THESE CLOUDS MAY BRING SLIGHTLY COOLER THAN FORECAST MAX TEMPS ACROSS OUR SOUTHERN TIER COUNTIES FROM FORECAST VALUES IN THE UPPER 70S TO THE MID 70S. DRY CONDITIONS WILL PREVAIL...BUT THOSE UNDER THE STRATUS DECK COULD HAVE A FEW SPRITZ OF NON-MEASURABLE DRIZZLE WHICH THE HRRR MODEL ADVERTISED ACROSS LEVY AND MARION COUNTIES MIDDAY. && .AVIATION...PREVAILING VFR TODAY WITH MVFR DUE TO GROUND FOG POSSIBLE TONIGHT AT GNV. && .MARINE...TWEAKED THE WAVE HEIGHTS DOWNWARD BY AROUND 1 FT BASED ON OBSERVATIONS...WITH FORECAST HEIGHTS OF 1-2 FT NEARSHORE TODAY TO 2-3 FT OFFSHORE. LIGHT WNW WINDS 10 KTS WILL PREVAIL. WINDS BEGIN TO INCREASE FROM THE SOUTH TUESDAY AS THE GRADIENT STRENGTHENS AHEAD OF APPROACHING FRONTAL SYSTEM. RIP CURRENTS: MODERATE RISK TODAY DUE TO PERSISTENT EASTERLY GROUND SWELLS NEAR 1 FT WITH PERIODS OF 11 SECONDS. && .PRELIMINARY POINT TEMPS/POPS... AMG 79 52 81 56 / 0 10 20 60 SSI 75 56 75 58 / 0 0 10 50 JAX 78 52 81 56 / 0 10 10 40 SGJ 74 55 77 59 / 0 10 10 40 GNV 79 50 80 56 / 0 10 20 50 OCF 79 50 81 57 / 0 10 10 50 && .JAX WATCHES/WARNINGS/ADVISORIES... FL...NONE. GA...NONE. AM...NONE. && $$ ENYEDI/GUILLET
AREA FORECAST DISCUSSION
NWS POCATELLO ID
115 PM MDT MON MAR 10 2014 .SHORT TERM...TONIGHT THROUGH WEDNESDAY. A STRONG STORM CONTINUES TO SLOWLY PUSH EAST ACROSS THE WEST. AS THE SYSTEM MOVES OVER IDAHO...IT WILL ACTUALLY BEGIN TO DIG MORE SOUTH AND SETTLE OVER SOUTHERN UTAH AND NEVADA BY TOMORROW AFTERNOON. SNOW LEVELS WILL CONTINUE TO FALL AS A COLD FRONT WORKS ACROSS THE AREA...AND FALL TO THE VALLEY FLOORS AREAWIDE BY MORNING. STRONG WINDS WILL CONTINUE IN THE HIGHER ELEVATIONS AND ALSO ACROSS THE SNAKE PLAIN THIS EVENING. WE ARE ALREADY SEEING LOCALIZED GUSTS IN EXCESS OF 60MPH ACROSS THE PLAIN...BUT MOST GUSTS WILL NOT EXCEED 55MPH. THE WIND ADVISORY REMAINS IN EFFECT FOR THE SNAKE PLAIN UNTIL 9PM. HOWEVER...THERE IS SOME INDICATION THAT WE MAY NEED TO EXTEND THAT UNTIL MIDNIGHT AND PERHAPS EXTEND IT INTO THE SOUTHERN HIGHLANDS ESPECIALLY AS THE WINDS SWITCH TO THE NORTHWEST. IN TERMS OF PRECIPITATION...THE PATTERN BECOMES RATHER COMPLEX THIS EVENING. IN TERMS OF THE MOUNTAINS...WE WILL SEE TWO DISTINCT AREAS OF ENHANCED MOISTURE. THE FIRST IS ACROSS THE UPPER SNAKE HIGHLANDS AND SOUTHWARD TOWARD BEAR LAKE. THE OTHER IS IN NORTHWEST FLOW ACROSS CENTRAL MOUNTAINS FROM CHALLIS TO GALENA SUMMIT. THE BIGGER AMOUNTS OVERALL WILL FALL OVER THE EAST. THE THIRD AREA IS A COMBINATION OF CONVERGENCE AND UPSLOPE. BY MORNING...AN AREA OF CONVERGENCE WILL LIE ACROSS THE SNAKE PLAIN NORTH AND EAST OF CRATERS TO POCATELLO LINE. UPSLOPE WILL ENHANCE THIS MOISTURE BAND ACROSS THE BENCHES AND ADJACENT MOUNTAINS FROM NEAR ST. ANTHONY TO AROUND POCATELLO. SNOW LEVELS WILL HOVER AROUND 4500-5000FT SO THESE AREAS WILL SEE AT LEAST MIX DOWN LOW AND ALL SNOW ABOVE THE BENCHES. IN TERMS OF ADDITIONAL PRECIPITATION OVERNIGHT...THE MOUNTAINS WILL SEE 0.10-0.20 INCHES ACROSS THE WEST AND 0.20-0.50 INCHES IN THE EAST. SNOWFALL AMOUNTS WILL BE A TRACE TO 3 INCHES IN THE MOUNTAINS. SOME BLOWING/DRIFTING IS POSSIBLE IN THE MOUNTAINS BUT WILL NOT BE WIDESPREAD IT APPEARS. WE MAY SEE A DUSTING ACROSS THE SNAKE PLAIN ESPECIALLY EAST OF I-15 BUT IT WILL NOT STICK AROUND LONG. IN TERMS OF WINTER AND FLOOD HEADLINES...WE WILL LET ALL WATCHES AND WARNINGS RIDE AND WILL LET THE EVENING SHIFT DECIDE IF ANYTHING NEEDS TO BE EXTENDED. BY TUESDAY AFTERNOON...WE WILL SEE ANY RAIN OR SNOW CONFINED TO AROUND BEAR LAKE AND DRIER AIR AND HIGH PRESSURE BUILDS INTO IDAHO. WE WILL SEE GUSTY NORTH TO NORTHEAST WINDS ACROSS THE ENTIRE AREA. IT WILL BE A BIT COOLER TOMORROW AS WELL. TUESDAY NIGHT AND WEDNESDAY WILL BE VERY DRY. WITH THE DRY AREA MOVING IN...THIS SHOULD ALLOW FOR A VERY CHILLY NIGHT ACROSS THE AREA AND A DECENT WARMUP ON WEDNESDAY. LOWS WILL LIKELY DROP INTO THE SINGLE DIGITS FOR HIGHER VALLEYS AND ISLAND PARK...WITH 10S AND 20S ELSEWHERE. GUIDANCE ACTUALLY POINTS TO EVEN COLDER TEMPERATURES BUT FOR NOW TRENDED ONLY PARTIALLY THAT DIRECTION. HIGHS BOUNCE BACK INTO 40S/LOWS 50S IN THE VALLEYS AND LOW/MID 30S AT RIDGETOP. KEYES .LONG TERM...THU NIGHT THROUGH NEXT MON NIGHT. LONGWAVE PATTERN INDICATES A HIGH AMPLITUDE RIDGE TO THE WEST OF IDAHO THAT SLOWLY DE-AMPLIFIES AND SHIFTS TO THE COAST STARTING SAT NIGHT. THERE ARE A COUPLE OF WEAK TROUGHS THAT MOVE DOWN THE BACKSIDE OF THE RIDGE...THE MOST LIKELY ONE TO AFFECT THE FORECAST AREA IS A FRI NIGHT/SAT SHORTWAVE. ZERO TO LITTLE EFFECT IS EXPECTED SOUTH OF POCATELLO...AND ONLY LITTLE EFFECT NORTH OF THIS. THE MAIN FORECAST PROBLEM IS HOW WARM IT WILL GET...WITH THE ECMWF BEING COLDER AND CLOUDIER. HAVE SPLIT THE DIFFERENCE...WHICH GETS LARGE BEYOND THE FRI NIGHT TROUGH. NO REAL SIGNIFICANT WIND WITH TEMPS GENERALLY ABOVE SEASONAL NORMALS. MESSICK && .AVIATION...WIND HAVING A HARD TIME DEVELOPING...AND SUN VALLEY JUST BELOW FIELD MINIMUMS. LOWEST CIGS EXPECTED WITH FRONTAL PASSAGE DURING THE MID- TO LATE AFTERNOON. FOR ALL AIRDROMES. LOWEST CIGS EXPECTED ARE MARGINAL VFR. HRRR GUIDANCE OF LATE NOW SUGGESTS STRONG WINDS SHORTLY AFTER 11/01Z IN THE KPIH AREA. SHOULDN`T BE MUCH OF A PROBLEM SINCE THEY ARE ALIGNED WITH THE RUNWAY. SKIES SHOULD CLEAR DURING THE LATE EVENING HOURS. MESSICK && .HYDROLOGY...MODERATE TO HEAVY RAINFALL BELOW 6500 FEET COMBINED WITH MELTING SNOW WILL CREATE AN INCREASED THREAT OF FLOODING FOR SMALL STREAMS AND LOW LYING AREAS IN THE BIG AND LITTLE WOOD RIVER REGION AND THE UPPER SNAKE HIGHLANDS FOR THE NEXT SEVERAL HOURS. THESE AREAS INCLUDE THE CITIES OF KETCHUM...HAILEY... ASHTON AND ST ANTHONY. A FLOOD WATCH REMAINS IN EFFECT FOR THESE AREAS. FLOODING IS NOT EXPECTED FOR THE MAIN STEM RIVERS AT THIS TIME. WYATT && .PIH WATCHES/WARNINGS/ADVISORIES... WIND ADVISORY UNTIL 9 PM MDT THIS EVENING IDZ017-020-021. FLOOD WATCH UNTIL 6 PM MDT THIS EVENING BELOW 6500 FEET FOR THE IDZ031. WINTER STORM WARNING UNTIL 6 PM MDT THIS EVENING ABOVE 7500 FEET FOR THE IDZ018-031. FLOOD WATCH UNTIL MIDNIGHT MDT TONIGHT BELOW 6500 FEET FOR THE IDZ019. WINTER STORM WARNING UNTIL MIDNIGHT MDT TONIGHT ABOVE 7000 FEET FOR THE IDZ019. && $$
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
922 PM CDT Tue Mar 11 2014 .UPDATE... ISSUED AT 921 PM CDT TUE MAR 11 2014 Did a quick update and extended the high wind warning further east based off obs and HRRR guidance. && .SHORT TERM...(This evening through Wednesday) ISSUED AT 316 PM CDT TUE MAR 11 2014 A strong upper level system will pass across western Kansas this evening. Just ahead of this feature, a mid level baroclinic zone will develop, and there will be just enough mid level moisture and lift to help generate some light precipitation, mainly along interstate 70. Rain can be expected at the onset as a nearly dry adiabatic layer will extend 2000 ft below the freezing level. However, continued cold advection and wet bulbing will cool the boundary layer enough for snow to reach the ground near or after 00z. Some accumulation of snow is possible, but due to the brevity of the event, amounts should remain less than an inch at Hays and Wakeeney. Due to the high winds, measuring this snow will be difficult at best. A high wind warning is still in effect for much of western Kansas, with a wind advisory further east. Temperatures will drop into the mid 20s to near 30 degrees by Wednesday morning. In the wake of the upper level system, Wednesday will still be breezy, with mostly sunny skies and highs in the lower 50s. .LONG TERM...(Wednesday night through Tuesday) ISSUED AT 309 PM CDT TUE MAR 11 2014 A relatively active spring-like pattern is in store with frequent frontal passages through the extended (days 3-7) period, which will result in temperature fluctuations and chances for rain or snow by the weekend. Thursday will bring warm dry and breezy if not borderline windy conditions as mixing ensues by late morning and early afternoon. Warmer temperatures will be achieved largely to downslope winds with warmest temperatures approaching 70 degrees perhaps focused farther north across west central Kansas counties where the 850 mb thermal ridge will be. Temperatures elsewhere should be at least 65 degrees and up by the afternoon. Temperatures overnight Thursday and Friday morning will be influenced by a relatively warm boundary layer to begin with, clear skies and at least some mixing near the surface, which could result in mild lows barely falling into the upper 30s in the far west. Once the dry frontal passage occurs, temperatures will likely moderate slightly upward again on Saturday back into the 60s, with yet another surface frontal boundary affecting the area Saturday night or early Sunday. A shortwave digging into the southern High Plains is indicated will bring an upper deformation zone across the area with potential for a weakly organized band of rain and rain or snow depending on the thermal profiles realized. The remainder of the period heading into Monday appears continued slightly normal or near normal conditions with highs the 60s and lows in the 30s. && .AVIATION...(For the 00Z TAFS through 00Z Wednesday evening) ISSUED AT 600 PM CDT TUE MAR 11 2014 Two concerns for the TAFs... 1) winds and 2) MVFR cigs. First, winds will be northerly 30-35 kt with gusts to 50 kt early and then decrease 10-18 kt overnight. An increase of NW 15-20 kt is expected tomorrow by late morning. MVFR cigs will be possible tonight with VFR conditions expected after 04Z. && .PRELIMINARY POINT TEMPS/POPS... DDC 28 53 26 66 / 20 0 0 0 GCK 27 52 24 66 / 20 0 0 0 EHA 28 50 28 65 / 10 0 0 0 LBL 27 52 25 66 / 10 0 0 0 HYS 28 52 24 67 / 60 0 0 0 P28 31 54 28 67 / 20 0 0 0 && .DDC WATCHES/WARNINGS/ADVISORIES... HIGH WIND WARNING until 11 PM CDT /10 PM MDT/ this evening FOR KSZ043>046-061>066-074>081-084>090. WIND ADVISORY until 11 PM CDT this evening FOR KSZ030-031. && $$ UPDATE...Sugden SHORT TERM...Finch LONG TERM...Russell AVIATION...Sugden
AREA FORECAST DISCUSSION
NWS TOPEKA KS
639 PM CDT Tue Mar 11 2014 ...Update to aviation forecast discussion and to add thunderstorm chances in the east for a few hours this evening... .SHORT TERM...(This Evening through Tonight) Issued at 322 PM CDT TUE MAR 11 2014 Late this afternoon, surface boundary bisects the CWA stretching just west of Wichita to the northeast to Topeka and further east north of KMCI. Several convergence zones ahead this boundary, with strongest axis stretching along the I-35/335 corridor. Will need to watch for potential development of convection along this corridor through 6pm as primary cold front moves east. Instability along and head of this front remains meager, with RAP analysis only indicating CAPE values 100-300 J/KG. If storms would happen to develop, the main impact would be small hail with the longevity of convection in the CWA minimal. The other concern heading into the overnight hours will be strong gradient winds. We`re already seeing advisory level winds in the far NW portion of the CWA at this hour, and as the surface boundary settles southeast, these strong gradient winds will swing through the CWA. By midnight, sfc pressure gradient should begin to weaken as the developing sfc low moves through the MO bootheel. The shortwave responsible for these strong winds and increasing precipitation chances is just beginning to enter the Western Plains this afternoon. A linear band of mid-level frontogenesis across NE/IA slopes back to western KS at 3pm. Short term model guidance continues to suggest that this band will slowly move southeast this evening. While the western flank of the mid-level lift should hold together the further southeast it tracks, the eastern areas of precip across NE/IA will dissipate as a new baroclinic zone is reestablished further south across eastern KS and northern Missouri. Precipitation should blossom shortly after 00Z along the eastern edges of the CWA. Given the position of the shortwave and how the wave pivots eastward, the majority of the heavy precipitation should take place just east of the CWA. Latest hopWRF, HRRR, RAP support the idea of a brief window of 3-5 hrs of a rain/snow mixture bisecting the CWA with most of the activity diminishing or moving east by 1am. Accumulations should remain light given the warm grounds, but could see up to an inch of snow in some spots where efficient rates can overtake boundary layer temps. .LONG TERM...(Wednesday Night through Tuesday) Issued at 322 PM CDT TUE MAR 11 2014 After the past two days, Wednesday will feel chilly with temperatures rebounding into the upper 40s to lower 50s. Will watch for an increase in low-level clouds late morning, as a secondary wave rotates southward into the area. A quick rebound above normal is expected by Thursday and Friday ahead of yet another shortwave pivoting through the southern Rockies. Temperatures on Thursday will rebound into the 60s, with a front dropping southward on Friday lowering readings a few degrees. Saturday-Monday: The aforementioned shortwave should pass far enough to the south Friday night to have minimal impact on the CWA leaving conditions pleasant for Saturday. A slightly more amplified flow pattern will drop colder air southward again on Sunday, but this cooldown should last no longer than a day as increasing southwesterly flow ushers above normal temperatures into the region to begin next week. Have bumped up temperatures for Monday. && .AVIATION...(For the 00Z TAFs through 00Z Wednesday Evening) Issued at 633 PM CDT TUE MAR 11 2014 Strong winds continue through midnight and only come down a few knots after that. Rain/Thunder chances in the TOP/FOE area in the next hour or so with a heavier shower possible 02-06z. Precipitation moves very quickly eastward after midnight and will set TAF back to vfr conditions at that time. Thunder chances expected to stay east of MHK. && .TOP WATCHES/WARNINGS/ADVISORIES... WIND ADVISORY until 1 AM CDT Wednesday FOR KSZ011-012-022>024- 026-036>040-054>056-058-059. WIND ADVISORY until 10 PM CDT this evening FOR KSZ008>010-020- 021-034-035. && $$ SHORT TERM...DUX LONG TERM...DUX AVIATION...67
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
222 PM CDT Mon Mar 10 2014 ...Updated long term discussion... .SHORT TERM...(Today and tonight) ISSUED AT 345 AM CDT MON MAR 10 2014 The large scale zonal flow pattern across much of the central and northern CONUS will lead to continued lower-mid tropospheric downslope conditions for the Western Plains today. A very warm lower troposphere is already in place just off the surface (850mb temperatures of +16 to +18C per the RAP analysis yesterday evening across the northwestern portion of Kansas). Overnight temperatures through 08Z have been rather mild with upper 30s to mid 40s quite common across much of southwestern and west central Kansas. The aforementioned very warm lower troposphere and a warm start to the day will lead to the already advertised very warm afternoon. We went ahead and adjusted the afternoon temperatures up another degree or two with some 80-degree highs now forecast for the Hays area as well as the Red Hills region near the Oklahoma border. 75 to 78F for highs will be common elsewhere. Winds will be very light today with the MSLP gradient quite relaxed across western Kansas thanks to several mesoscale low pressure perturbations across the Western and Central Plains embedded within a larger synoptic scale lee trough across much of the Great Plains. An upper level trough will be forming across the Intermountain West and Northern Rockies late tonight, and this will allow a more prominent surface low to form across far northwestern Kansas. This will increase the pressure gradient some overnight leading to increased overnight winds around 11 to 14 knots. Lows will again be fairly mild by early-mid March standards in the upper 30s to lower 40s. .LONG TERM...(Tuesday night through Monday) ISSUED AT 221 PM CDT MON MAR 10 2014 Very windy conditions will continue early Tuesday night based on the tight surface pressure gradient located near the Oklahoma border and the surface to 850mb winds forecast from the latest model soundings. In addition to the strong winds, low level moisture will be on the increase Tuesday evening. Based on the depth of this moisture early Tuesday night there still appears to be a chance for light precipitation, especially across north central Kansas. Will retain the higher chances early Tuesday night near the I-70 corridor based on the depth of the low level moisture along with some mid level forcing forecast to be present at 00z Wednesday ahead of an upper level trough. As for precipitation type Tuesday evening will favor mainly drizzle/rain given the 12z BUFR soundings in the Hays area. A mix of drizzle and light snow is still not out of the question for a few hours prior to the precipitation chances shifting east as the upper level trough moves across central Kansas. Further south will lower precipitation chances but kept a mention of patchy light drizzle going until around 03z. Gusty winds are expected to decrease into the 10 to 15 mph range after midnight as a surface and 850mb high begins to build into western Kansas. Skies are also expected to clear from north to south. On Wednesday the surface to 850mb high will move into the southern plains and a northwesterly downslope flow will improve across western Kansas. This downslope flow will continue on Thursday. 850mb temperature from 00z Thursday to 00z Friday across all of western Kansas warm around 10c and based on this warming trend and the 850mb temperatures at 00z Thursday forecast to range from 10C to 15c will continue to favor highs rebounding from the 50s on Wednesday with 60s for highs on Thursday. A weak upper level disturbance will cross the central plains Thursday night/early Friday as a cold front crosses western Kansas. At this time it appears only mid level moisture will accompany this upper wave so at this time only mention an increase in cloud cover. By the start of the weekend period models begin to diverge on the development of an upper level ridge axis across the western United States along with several subtle upper level disturbance rotating around this upper ridge and out into the plains. At this time given a persistent northwest flow will continue to favor the latest CRExtendFcst_Init with keeping temperatures at or slightly above the seasonal normals from Friday through Sunday. && .AVIATION...(For the 18Z TAFS through 18Z Tuesday afternoon) ISSUED AT 1257 PM CDT MON MAR 10 2014 A weak surface trough will develop in the lee of the Rockies though tonight, resulting in a resumption of southerly winds. A strong cold front will pass across KGCK/KDDC/KHYS between 12-15z Tuesday, resulting in increasing northwesterly winds. VFR conditions will persist in the absence of low level moisture. && .PRELIMINARY POINT TEMPS/POPS... DDC 40 57 26 53 / 0 20 10 0 GCK 39 55 24 52 / 0 20 10 0 EHA 41 58 26 50 / 0 10 10 0 LBL 39 58 25 52 / 0 10 10 0 HYS 39 55 26 52 / 0 30 30 0 P28 41 62 29 54 / 0 20 10 0 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...Umscheid LONG TERM...Burgert AVIATION...Finch
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
102 PM CDT Mon Mar 10 2014 ...Updated for aviation discussion... .SHORT TERM...(Today and tonight) ISSUED AT 345 AM CDT MON MAR 10 2014 The large scale zonal flow pattern across much of the central and northern CONUS will lead to continued lower-mid tropospheric downslope conditions for the Western Plains today. A very warm lower troposphere is already in place just off the surface (850mb temperatures of +16 to +18C per the RAP analysis yesterday evening across the northwestern portion of Kansas). Overnight temperatures through 08Z have been rather mild with upper 30s to mid 40s quite common across much of southwestern and west central Kansas. The aforementioned very warm lower troposphere and a warm start to the day will lead to the already advertised very warm afternoon. We went ahead and adjusted the afternoon temperatures up another degree or two with some 80-degree highs now forecast for the Hays area as well as the Red Hills region near the Oklahoma border. 75 to 78F for highs will be common elsewhere. Winds will be very light today with the MSLP gradient quite relaxed across western Kansas thanks to several mesoscale low pressure perturbations across the Western and Central Plains embedded within a larger synoptic scale lee trough across much of the Great Plains. An upper level trough will be forming across the Intermountain West and Northern Rockies late tonight, and this will allow a more prominent surface low to form across far northwestern Kansas. This will increase the pressure gradient some overnight leading to increased overnight winds around 11 to 14 knots. Lows will again be fairly mild by early-mid March standards in the upper 30s to lower 40s. .LONG TERM...(Tuesday through Sunday) ISSUED AT 345 AM CDT MON MAR 10 2014 Medium range models indicate an upper level shortwave digging southeast across the Colorado Rockies into the Western High Plains Tuesday setting up precip chances for portions of western and central Kansas late Tuesday afternoon and evening. A strong attendant cold front ahead of the approaching system will push southeast across western Kansas by Tuesday afternoon creating ample forcing near the surface. Meanwhile, an +90kt upper level jet axis is projected to shift southeast across western Kansas Tuesday afternoon/evening as it streams northeast out of the trough axis in the Desert Southwest. As a result, light rain is expected to develop across some areas of central and western Kansas with a possible brief switchover so snow overnight as the upper level system quickly moves through. However, lacking moisture availability in the lower/mid levels may hinder much in the way of measurable precip across the area. Dry conditions are then likely through at least Thursday as the flow aloft becomes more westerly while moisture remains generally absent. Temperatures will cool off quite a bit Tuesday as arctic air spills southward into western Kansas in wake of the cold front moving through by early afternoon. Although high temperatures are likely to occur earlier in the day, highs are still expected up into the 50s(F) across central and west central Kansas with temperatures only down into the 40s(F) first thing Tuesday morning. The lower to possibly the mid 60s(F) are still likely across south central Kansas before the front moves through. More seasonal temperatures are then forecast through the end of the week as the flow aloft becomes more zonal. && .AVIATION...(For the 18Z TAFS through 18Z Tuesday afternoon) ISSUED AT 1257 PM CDT MON MAR 10 2014 A weak surface trough will develop in the lee of the Rockies though tonight, resulting in a resumption of southerly winds. A strong cold front will pass across KGCK/KDDC/KHYS between 12-15z Tuesday, resulting in increasing northwesterly winds. VFR conditions will persist in the absence of low level moisture. && .PRELIMINARY POINT TEMPS/POPS... DDC 78 40 57 26 / 0 0 20 10 GCK 76 39 55 24 / 0 0 20 10 EHA 77 41 58 26 / 0 0 10 10 LBL 77 39 58 25 / 0 0 10 10 HYS 80 39 55 26 / 0 0 30 30 P28 79 41 62 29 / 0 0 20 10 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...Umscheid LONG TERM...JJohnson AVIATION...Finch
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
603 AM CDT Mon Mar 10 2014 ...UPDATE TO AVIATION... .SHORT TERM...(Today and tonight) ISSUED AT 345 AM CDT MON MAR 10 2014 The large scale zonal flow pattern across much of the central and northern CONUS will lead to continued lower-mid tropospheric downslope conditions for the Western Plains today. A very warm lower troposphere is already in place just off the surface (850mb temperatures of +16 to +18C per the RAP analysis yesterday evening across the northwestern portion of Kansas). Overnight temperatures through 08Z have been rather mild with upper 30s to mid 40s quite common across much of southwestern and west central Kansas. The aforementioned very warm lower troposphere and a warm start to the day will lead to the already advertised very warm afternoon. We went ahead and adjusted the afternoon temperatures up another degree or two with some 80-degree highs now forecast for the Hays area as well as the Red Hills region near the Oklahoma border. 75 to 78F for highs will be common elsewhere. Winds will be very light today with the MSLP gradient quite relaxed across western Kansas thanks to several mesoscale low pressure perturbations across the Western and Central Plains embedded within a larger synoptic scale lee trough across much of the Great Plains. An upper level trough will be forming across the Intermountain West and Northern Rockies late tonight, and this will allow a more prominent surface low to form across far northwestern Kansas. This will increase the pressure gradient some overnight leading to increased overnight winds around 11 to 14 knots. Lows will again be fairly mild by early-mid March standards in the upper 30s to lower 40s. .LONG TERM...(Tuesday through Sunday) ISSUED AT 345 AM CDT MON MAR 10 2014 Medium range models indicate an upper level shortwave digging southeast across the Colorado Rockies into the Western High Plains Tuesday setting up precip chances for portions of western and central Kansas late Tuesday afternoon and evening. A strong attendant cold front ahead of the approaching system will push southeast across western Kansas by Tuesday afternoon creating ample forcing near the surface. Meanwhile, an +90kt upper level jet axis is projected to shift southeast across western Kansas Tuesday afternoon/evening as it streams northeast out of the trough axis in the Desert Southwest. As a result, light rain is expected to develop across some areas of central and western Kansas with a possible brief switchover so snow overnight as the upper level system quickly moves through. However, lacking moisture availability in the lower/mid levels may hinder much in the way of measurable precip across the area. Dry conditions are then likely through at least Thursday as the flow aloft becomes more westerly while moisture remains generally absent. Temperatures will cool off quite a bit Tuesday as arctic air spills southward into western Kansas in wake of the cold front moving through by early afternoon. Although high temperatures are likely to occur earlier in the day, highs are still expected up into the 50s(F) across central and west central Kansas with temperatures only down into the 40s(F) first thing Tuesday morning. The lower to possibly the mid 60s(F) are still likely across south central Kansas before the front moves through. More seasonal temperatures are then forecast through the end of the week as the flow aloft becomes more zonal. && .AVIATION...(For the 12Z TAFS through 12Z Tuesday morning) ISSUED AT 600 AM CDT MON MAR 10 2014 VFR conditions will prevail at all TAF sites through late this evening. As for winds, a lee side trough of low pressure will persist across southeastern Colorado into northwestern Kansas through tonight resulting in light southwesterly winds across central Kansas to more light and variable winds closer to the Colorado border. && .PRELIMINARY POINT TEMPS/POPS... DDC 78 40 57 27 / 0 0 20 20 GCK 76 39 55 26 / 0 0 20 20 EHA 77 41 58 27 / 0 0 10 20 LBL 77 39 58 27 / 0 0 10 20 HYS 80 39 55 27 / 0 0 30 40 P28 79 41 62 30 / 0 0 20 20 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...Umscheid LONG TERM...JJohnson AVIATION...JJohnson
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
348 AM CDT Mon Mar 10 2014 ...Updated Short Term and Long Term sections... .SHORT TERM...(Today and tonight) ISSUED AT 345 AM CDT MON MAR 10 2014 The large scale zonal flow pattern across much of the central and northern CONUS will lead to continued lower-mid tropospheric downslope conditions for the Western Plains today. A very warm lower troposphere is already in place just off the surface (850mb temperatures of +16 to +18C per the RAP analysis yesterday evening across the northwestern portion of Kansas). Overnight temperatures through 08Z have been rather mild with upper 30s to mid 40s quite common across much of southwestern and west central Kansas. The aforementioned very warm lower troposphere and a warm start to the day will lead to the already advertised very warm afternoon. We went ahead and adjusted the afternoon temperatures up another degree or two with some 80-degree highs now forecast for the Hays area as well as the Red Hills region near the Oklahoma border. 75 to 78F for highs will be common elsewhere. Winds will be very light today with the MSLP gradient quite relaxed across western Kansas thanks to several mesoscale low pressure perturbations across the Western and Central Plains embedded within a larger synoptic scale lee trough across much of the Great Plains. An upper level trough will be forming across the Intermountain West and Northern Rockies late tonight, and this will allow a more prominent surface low to form across far northwestern Kansas. This will increase the pressure gradient some overnight leading to increased overnight winds around 11 to 14 knots. Lows will again be fairly mild by early-mid March standards in the upper 30s to lower 40s. .LONG TERM...(Tuesday through Sunday) ISSUED AT 345 AM CDT MON MAR 10 2014 Medium range models indicate an upper level shortwave digging southeast across the Colorado Rockies into the Western High Plains Tuesday setting up precip chances for portions of western and central Kansas late Tuesday afternoon and evening. A strong attendant cold front ahead of the approaching system will push southeast across western Kansas by Tuesday afternoon creating ample forcing near the surface. Meanwhile, an +90kt upper level jet axis is projected to shift southeast across western Kansas Tuesday afternoon/evening as it streams northeast out of the trough axis in the Desert Southwest. As a result, light rain is expected to develop across some areas of central and western Kansas with a possible brief switchover so snow overnight as the upper level system quickly moves through. However, lacking moisture availability in the lower/mid levels may hinder much in the way of measurable precip across the area. Dry conditions are then likely through at least Thursday as the flow aloft becomes more westerly while moisture remains generally absent. Temperatures will cool off quite a bit Tuesday as arctic air spills southward into western Kansas in wake of the cold front moving through by early afternoon. Although high temperatures are likely to occur earlier in the day, highs are still expected up into the 50s(F) across central and west central Kansas with temperatures only down into the 40s(F) first thing Tuesday morning. The lower to possibly the mid 60s(F) are still likely across south central Kansas before the front moves through. More seasonal temperatures are then forecast through the end of the week as the flow aloft becomes more zonal. && .AVIATION...(For the 06Z TAFS through 06Z Monday night) ISSUED AT 1146 PM CDT SUN MAR 9 2014 The downslope pattern we are in will lead to continued VFR conditions through Tuesday evening. Given the overall broad low pressure across the the western plains, there will be very little pressure gradient leading to light winds at less than 8 knots during much of the day Tuesday. && .PRELIMINARY POINT TEMPS/POPS... DDC 78 40 57 27 / 0 0 20 20 GCK 76 39 55 26 / 0 0 20 20 EHA 77 41 58 27 / 0 0 10 20 LBL 77 39 58 27 / 0 0 10 20 HYS 80 39 55 27 / 0 0 30 40 P28 79 41 62 30 / 0 0 20 20 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...Umscheid LONG TERM...JJohnson AVIATION...Umscheid
AREA FORECAST DISCUSSION
NWS LAKE CHARLES LA
407 PM CDT MON MAR 10 2014 .DISCUSSION... LATEST WATER VAPOR SATELLITE IMAGERY/UPPER AIR ANALYSIS SHOWED AND UPPER LOW DRIFTING EAST ACROSS NORTHERN MEXICO...WITH AN UPSTREAM SHORTWAVE TROF TRANSLATING THROUGH THE PAC NW. AT THE SFC...BROAD HIGH PRESSURE STRETCHED ACROSS THE NORTHERN GULF COAST. AFTER CONTENDING WITH AREAS OF DENSE FOG THIS MORNING...A RATHER PLEASANT DAY HAS UNFOLDED ACROSS THE REGION...WITH PLENTY OF SUN RESULTING IN TEMPERATURES CLIMBING INTO THE LOWER TO MID 70S. THE AREA OF SURFACE HIGH PRESSURE IS PROGGED TO CONTINUE SHIFTING OFF A LITTLE TO THE EAST INTO TONIGHT...ALLOWING FOR AT LEAST A WEAK RETURN FLOW TO SET UP. WITH SHELF WATER TEMPERATURES STILL IN THE MID/UPPER 50S...AREAS OF SEA FOG ARE EXPECTED TO DEVELOP THIS EVENING AS AIR CHARACTERIZED BY LOWER 60S DEWPOINTS BEGINS TO ADVECT ATOP IT. LATEST HRRR AND RUC FCSTS INDICATE FOG DEVELOPING OVER THE NEARSHORE WATERS WEST OF CAMERON...THEN DEVELOPING FARTHER NORTH/INLAND DURING THE OVERNIGHT HOURS. DREW IN AREAS OF FOG THAT GENERALLY MATCHES THIS EVOLUTION...BUT AM A LITTLE HESITANT TO ISSUE AN ADVISORY AT THIS TIME. WOULD PREFER TO LET THE EVENING CREW SEE HOW THE SITUATION BEGINS TO EVOLVE. THE UPPER LOW TO THE WEST IS EXPECTED TO CONTINUE EASTWARD...WITH SHOWERS AND THUNDERSTORMS EXPECTED TO FORM ALONG AND AHEAD OF AN ASSOCIATED N-S LOW PRESSURE TROF. MOST OF THIS ACTIVITY CONTINUES TO BE PROGGED TO OCCUR OVER THE GULF WATERS AND COASTAL AREAS ROUGHLY ALONG AND SOUTH OF I-10...AND SO THE HIGHEST POPS WERE RETAINED IN THESE AREAS. RAINFALL IS FCST TO END FROM WEST TO EAST DURING THE AFTERNOON HOURS...BUT IT IS POSSIBLE THAT ANY SEA FOG WILL PERSIST AND PERHAPS EVEN SPREAD FARTHER EAST AMID WINDS BECOMING MORE FROM THE SW. ON THE HEELS OF THIS LEAD SYSTEM...A RELATIVELY STRONG COLD FRONT IS STILL ON TRACK TO SWEEP THROUGH THE REGION LATE TUESDAY NIGHT INTO EARLY WED. THIS WILL CERTAINLY BRING AN END TO ANY SEA FOG...AND WITH SIGNIFICANT MOISTURE HAVING BEEN SHUNTED EASTWARD BY THE LEAD SYSTEM...THE PASSAGE IS EXPECTED TO BE A DRY ONE. AMID BRISK NORTH WINDS...MUCH COOLER AND DRIER AIR WILL SPILL INTO THE REGION...WITH TEMPERATURES BY THURSDAY MORNING EXPECTED TO RANGE FROM THE MID 30S OVER INTERIOR EAST TEXAS AND CENTRAL LOUISIANA TO NEAR 40 ALONG THE COAST AS THE POST-FRONTAL HIGH SETTLES SOUTH INTO TEXAS. COOL TEMPERATURES ARE EXPECTED TO CONTINUE THROUGH THURSDAY...WITH HIGHS STRUGGLING TO REACH 60 FOR MUCH OF THE AREA. AS THE HIGH SHIFTS TO THE EAST THURSDAY NIGHT...TEMPERATURES WILL BEGIN TO MODERATE...WITH A WARMING TREND CONTINUING INTO THE START OF THE WEEKEND. THE FORECAST OVER THE WEEKEND AND INTO EARLY NEXT WEEK CONTINUES TO BE ONE OF LOW CONFIDENCE...AND GENERALLY A BLEND OF THE PREVIOUS FORECAST AND LATEST WPC GUIDANCE WAS USED. 13 && .MARINE... WEAK TO OCCASIONALLY MODERATE EASTERLY FLOW IS EXPECTED AHEAD OF AN UPPER LEVEL LOW THAT WILL BRING SHOWERS AND THUNDERSTORMS TO THE NORTHERN GULF TONIGHT AND TUESDAY. AREAS OF FOG ARE EXPECTED TO DEVELOP OVER THE NEARSHORE WATERS FROM CAMERON TO HIGH ISLAND THIS EVENING...THEN SUBSEQUENTLY SPREAD INTO SABINE AND CALCASIEU LAKES. A STRONG COLD FRONT WILL MOVE THROUGH AREA ON WEDNESDAY. INCREASED OFFSHORE FLOW IS FORECAST FOR WEDNESDAY AND WEDNESDAY NIGHT. WINDS AND SEAS WILL LIKELY BE WITHIN SMALL CRAFT ADVISORY RANGE WEDNESDAY AND WEDNESDAY NIGHT. WINDS WILL DIMINISH ON THURSDAY AS HIGH PRESSURE SETTLES OVER THE REGION. 13 && .PRELIMINARY POINT TEMPS/POPS... KLCH 57 71 57 65 / 50 50 10 10 KBPT 56 74 57 66 / 60 40 10 10 KAEX 55 74 56 62 / 20 40 10 10 KLFT 58 70 57 66 / 40 80 10 10 && .LCH WATCHES/WARNINGS/ADVISORIES... LA...NONE. TX...NONE. GM...NONE. && $$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
644 AM EDT MON MAR 10 2014 .SYNOPSIS... WHILE SOME SCATTERED SPRINKLES ARE POSSIBLE THIS AFTERNOON...THE REGION SHOULD REMAIN DRY UNTIL A POTENT LOW PRESSURE SYSTEM SPREADS RAIN AND SNOW OVER THE REGION TUESDAY NIGHT INTO WEDNESDAY. && .NEAR TERM /THROUGH TONIGHT/... SYNOPTIC MODELS INDICATE A SHORTWAVE WILL MOVE JUST NORTH OF THE FORECAST AREA DURING THE MORNING AND EARLY AFTERNOON HOURS. CURRENT THINKING IS THAT ANY PRECIPITATION WITH THIS SHORTWAVE SHOULD MISS THE FORECAST AREA. A SECOND WEAKER SHORTWAVE IS EXPECTED TO TRACK ACROSS THE CENTER OF THE FORECAST AREA...WITH SEVERAL HIGH-RES MODELS...INCLUDING THE RAP AND HRRR...PUTTING OUT A SMALL STRIPE OF PRECIPITATION. CONSIDERING HOW DRY THE 00Z PIT SOUNDING WAS...HAVE DECIDED TO JUST ADD SCATTERED SPRINKLES INTO THE FORECAST WITH MEASUREABLE RAIN NOT EXPECTED. SOUTHERLY WINDS AND WARM ADVECTION SHOULD RAISE TEMPERATURES INTO THE UPPER 40S AND 50S DESPITE CLOUD COVER. HIGH PRESSURE MAY NOSE IN FROM THE SOUTH OVERNIGHT. WIND SPEEDS WILL REMAIN UP OVERNIGHT...AND WITH SKIES ONLY PARTIALLY CLEARING...THINK THAT TONIGHT COULD BE RATHER WARM. WHILE LOCATIONS NORTH OF THE PENNSYLVANIA TURNPIKE THAT MAY STILL HAVE SOME SNOW COVER SHOULD DROP TOWARDS THE FREEZING MARK...REST OF THE REGION IS EXPECTED TO ONLY DROP INTO THE LOWER 40S. && .SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... A FRONTAL BOUNDARY WILL SAG ACROSS THE GREAT LAKES TUESDAY...ARRIVING LOCALLY TUESDAY EVENING. WHILE SOME LIGHT PRECIPITATION WILL BE POSSIBLE ALONG THE FRONT TUESDAY NIGHT...MORE SUBSTANTIAL PRECIPITATION IS NOT EXPECTED UNTIL LATE TUESDAY NIGHT INTO WEDNESDAY AS LOW PRESSURE ADVANCES ALONG THE FRONT. LOW PRESSURE SYSTEM WILL MOVE QUICKLY...PASSING FROM KENTUCKY WEDNESDAY MORNING TO THE NEW JERSEY COAST BY WEDNESDAY EVENING. BULK OF PRECIPITATION WILL FALL WEDNESDAY...WITH PRECIP RAPIDLY DIMINISHING FROM WEST TO EAST WEDNESDAY EVENING. THERE ARE STILL PLENTY OF DETAILS THAT WILL BRING CHANGES TO THE FORECAST. 00Z MODELS HAVE TRENDED SLIGHTLY COLDER...WHICH SHOULD ALLOW PRECIPITATION IN MOST LOCATIONS TO CHANGE FROM RAIN TO SNOW SLIGHTLY QUICKER. COUPLED JET IS MOST APPARENT IN 00Z NAM...ALTHOUGH GFS AND ECMWF BOTH SHOWED THIS SIGNATURE TO A LESSER EXTENT. CURRENT TIMING SUGGESTS HIGHEST RATES COULD OCCUR AS PRECIPITATION IS GENERALLY CHANGING FROM RAIN TO SNOW IN THE EARLY AFTERNOON. WARMER AIR ALOFT COULD ALSO ALLOW FOR A BRIEF PERIOD OF FREEZING RAIN. OVERALL...FEEL THAT SOUTHERNMOST LOCATIONS COULD PICK UP AROUND AN INCH OF WET SNOW DURING THE LATE AFTERNOON AND EVENING HOURS...WHILE LOCATIONS ALONG THE INTERSTATE 80 CORRIDOR COULD PICK UP SEVERAL INCHES OF SNOW DEPENDING ON JUST HOW LONG IT TAKES FOR PRECIPITATION TO CHANGE FROM RAIN TO SNOW IN THE MORNING. WILL ADD MENTION OF THE STORM IN THE HAZARDOUS WEATHER OUTLOOK BUT DO NOT HAVE ENOUGH CONFIDENCE IN ANY GIVEN SCENARIO TO ISSUE A WINTER STORM WATCH. MUCH COLDER AIR WILL MOVE IN BEHIND THE LOW PRESSURE SYSTEM WEDNESDAY NIGHT...AND TEMPERATURES WILL TAKE A TUMBLE ALL THE WAY INTO THE SINGLE DIGITS UP NORTH AND LOWER TEENS ELSEWHERE. && .LONG TERM /THURSDAY THROUGH SUNDAY/... HIGH PRESSURE WILL QUICKLY BUILD IN THURS. COLD AIR WONT LINGER LONG AS STRONG WAA KICKS IN BY THURS EVENING AS A WEAK SYSTEM APPROACHES FROM THE NW. THE COLDER THAN AVG TEMPS THURS WILL GIVE WAY TO SLIGHTLY WARMER THAN AVG TEMPS FRI BEFORE ANOTHER...WEAK COLD FRONT PUSHES THROUGH IN THE EARLY PORTION OF THE WEEKEND. TIMING OF THE FRONT REMAINS IN QUESTION AS MODELS HAVE SPED UP THE FEATURE SIGNIFICANTLY FROM EARLIER RUNS. COLDER AIR LINGERS THROUGH THE WEEKEND AS A BROAD TROUGH REMAINS ENTRENCHED OVER ERN CANADA. && .AVIATION /12Z MONDAY THROUGH FRIDAY/... A WEAK DISTURBANCE MAY BRING A BRIEF SHOWER THIS MORNING...BUT PRIMARILY THICKER CLOUD COVER. STILL EXPECTING MOSTLY VFR THROUGH MON WITH GUSTY SW WINDS DEVELOPING. CLOUDS DISSIPATE MON AFTN AND EVENING. LOW LEVEL MOISTURE COULD GENERATE SOME BORDERLINE MVFR STRATUS FOR ERN TERMINALS. .OUTLOOK.../MONDAY NIGHT THROUGH FRIDAY/... WIDESPREAD RESTRICTIONS ARE EXPECTED TUE NIGHT INTO WED EVENING AS LOW PRESSURE TRACKS ACROSS THE UPPER OH VALLEY. && .HYDROLOGY... THROUGH WEDNESDAY...THE BREEZY COMBINATION OF WARMTH WITH INCRSG DEWPOINTS FOLLOWED BY RAIN WL ELIMINATE ANY RMNG SNOW IN THE RIDGES. WITH THE QPF OF THE WEDNESDAY SYSTEM ON THE ORDER OF THREE QUARTERS TO AN INCH...FLOODING CONCERNS SHOULD BE LOCAL...HOWEVER...RIDGE ZONE CREEKS AND THE MONONGAHELA RIVER BASINS WL HAVE TO BE MONITORED AS THE RMNG WATER EQUIVALENT IS ACTIVATED. && .PBZ WATCHES/WARNINGS/ADVISORIES... MD...NONE. OH...NONE. PA...NONE. WV...NONE. && $$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
425 AM EDT MON MAR 10 2014 .SYNOPSIS... WHILE SOME SCATTERED SPRINKLES ARE POSSIBLE THIS AFTERNOON...THE REGION SHOULD REMAIN DRY UNTIL A POTENT LOW PRESSURE SYSTEM SPREADS RAIN AND SNOW OVER THE REGION TUESDAY NIGHT INTO WEDNESDAY. && .NEAR TERM /THROUGH TONIGHT/... SYNOPTIC MODELS INDICATE A SHORTWAVE WILL MOVE JUST NORTH OF THE FORECAST AREA DURING THE MORNING AND EARLY AFTERNOON HOURS. CURRENT THINKING IS THAT ANY PRECIPITATION WITH THIS SHORTWAVE SHOULD MISS THE FORECAST AREA. A SECOND WEAKER SHORTWAVE IS EXPECTED TO TRACK ACROSS THE CENTER OF THE FORECAST AREA...WITH SEVERAL HIGH-RES MODELS...INCLUDING THE RAP AND HRRR...PUTTING OUT A SMALL STRIPE OF PRECIPITATION. CONSIDERING HOW DRY THE 00Z PIT SOUNDING WAS...HAVE DECIDED TO JUST ADD SCATTERED SPRINKLES INTO THE FORECAST WITH MEASUREABLE RAIN NOT EXPECTED. SOUTHERLY WINDS AND WARM ADVECTION SHOULD RAISE TEMPERATURES INTO THE UPPER 40S AND 50S DESPITE CLOUD COVER. HIGH PRESSURE MAY NOSE IN FROM THE SOUTH OVERNIGHT. WIND SPEEDS WILL REMAIN UP OVERNIGHT...AND WITH SKIES ONLY PARTIALLY CLEARING...THINK THAT TONIGHT COULD BE RATHER WARM. WHILE LOCATIONS NORTH OF THE PENNSYLVANIA TURNPIKE THAT MAY STILL HAVE SOME SNOW COVER SHOULD DROP TOWARDS THE FREEZING MARK...REST OF THE REGION IS EXPECTED TO ONLY DROP INTO THE LOWER 40S. && .SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... A FRONTAL BOUNDARY WILL SAG ACROSS THE GREAT LAKES TUESDAY...ARRIVING LOCALLY TUESDAY EVENING. WHILE SOME LIGHT PRECIPITATION WILL BE POSSIBLE ALONG THE FRONT TUESDAY NIGHT...MORE SUBSTANTIAL PRECIPITATION IS NOT EXPECTED UNTIL LATE TUESDAY NIGHT INTO WEDNESDAY AS LOW PRESSURE ADVANCES ALONG THE FRONT. LOW PRESSURE SYSTEM WILL MOVE QUICKLY...PASSING FROM KENTUCKY WEDNESDAY MORNING TO THE NEW JERSEY COAST BY WEDNESDAY EVENING. BULK OF PRECIPITATION WILL FALL WEDNESDAY...WITH PRECIP RAPIDLY DIMINISHING FROM WEST TO EAST WEDNESDAY EVENING. THERE ARE STILL PLENTY OF DETAILS THAT WILL BRING CHANGES TO THE FORECAST. 00Z MODELS HAVE TRENDED SLIGHTLY COLDER...WHICH SHOULD ALLOW PRECIPITATION IN MOST LOCATIONS TO CHANGE FROM RAIN TO SNOW SLIGHTLY QUICKER. COUPLED JET IS MOST APPARENT IN 00Z NAM...ALTHOUGH GFS AND ECMWF BOTH SHOWED THIS SIGNATURE TO A LESSER EXTENT. CURRENT TIMING SUGGESTS HIGHEST RATES COULD OCCUR AS PRECIPITATION IS GENERALLY CHANGING FROM RAIN TO SNOW IN THE EARLY AFTERNOON. WARMER AIR ALOFT COULD ALSO ALLOW FOR A BRIEF PERIOD OF FREEZING RAIN. OVERALL...FEEL THAT SOUTHERNMOST LOCATIONS COULD PICK UP AROUND AN INCH OF WET SNOW DURING THE LATE AFTERNOON AND EVENING HOURS...WHILE LOCATIONS ALONG THE INTERSTATE 80 CORRIDOR COULD PICK UP SEVERAL INCHES OF SNOW DEPENDING ON JUST HOW LONG IT TAKES FOR PRECIPITATION TO CHANGE FROM RAIN TO SNOW IN THE MORNING. WILL ADD MENTION OF THE STORM IN THE HAZARDOUS WEATHER OUTLOOK BUT DO NOT HAVE ENOUGH CONFIDENCE IN ANY GIVEN SCENARIO TO ISSUE A WINTER STORM WATCH. MUCH COLDER AIR WILL MOVE IN BEHIND THE LOW PRESSURE SYSTEM WEDNESDAY NIGHT...AND TEMPERATURES WILL TAKE A TUMBLE ALL THE WAY INTO THE SINGLE DIGITS UP NORTH AND LOWER TEENS ELSEWHERE. && .LONG TERM /THURSDAY THROUGH SUNDAY/... HIGH PRESSURE WILL QUICKLY BUILD IN THURS. COLD AIR WONT LINGER LONG AS STRONG WAA KICKS IN BY THURS EVENING AS A WEAK SYSTEM APPROACHES FROM THE NW. THE COLDER THAN AVG TEMPS THURS WILL GIVE WAY TO SLIGHTLY WARMER THAN AVG TEMPS FRI BEFORE ANOTHER...WEAK COLD FRONT PUSHES THROUGH IN THE EARLY PORTION OF THE WEEKEND. TIMING OF THE FRONT REMAINS IN QUESTION AS MODELS HAVE SPED UP THE FEATURE SIGNIFICANTLY FROM EARLIER RUNS. COLDER AIR LINGERS THROUGH THE WEEKEND AS A BROAD TROUGH REMAINS ENTRENCHED OVER ERN CANADA. && .AVIATION /08Z MONDAY THROUGH FRIDAY/... A WEAK DISTURBANCE MAY BRING A BRIEF RAIN OR SNOW SHOWER EARLY TODAY...HOWEVER...VFR CONDITIONS ARE EXPECTED TO CONTINUE THROUGH THE DAY...WITH GUSTY SW WINDS DEVELOPING. EVENTUAL CLEARING OCCURS LATER MON EVENING. .OUTLOOK.../MONDAY NIGHT THROUGH FRIDAY/... WDSPRD RSTRNS ARE EXPD TUE NGT INTO WED EVE AS LOW PRES TRACKS ACRS THE UPR OH VLY RGN. && .HYDROLOGY... THROUGH WEDNESDAY...THE BREEZY COMBINATION OF WARMTH WITH INCRSG DEWPOINTS FOLLOWED BY RAIN WL ELIMINATE ANY RMNG SNOW IN THE RIDGES. WITH THE QPF OF THE WEDNESDAY SYSTEM ON THE ORDER OF THREE QUARTERS TO AN INCH...FLOODING CONCERNS SHOULD BE LOCAL...HOWEVER...RIDGE ZONE CREEKS AND THE MONONGAHELA RIVER BASINS WL HAVE TO BE MONITORED AS THE RMNG WATER EQUIVALENT IS ACTIVATED. && .PBZ WATCHES/WARNINGS/ADVISORIES... MD...NONE. OH...NONE. PA...NONE. WV...NONE. && $$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
121 PM EDT MON MAR 10 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 500 AM EDT MON MAR 10 2014 WV IMAGERY AND RUC ANALYSIS INDICATED WNW MID/UPPER LEVEL FLOW ACROSS SRN CANADA AND THE NRN CONUS WHICH HAS ALLOWED MILDER PACIFIC AIR TO SPREAD INTO THE PLAINS AND TOWARD THE WRN GREAT LAKES. A SHORTWAVE TROUGH NEAR LAKE WINNIPEG WAS MOVING INTO NW ONTARIO. AT THE SFC...LOW PRES WAS LOCATED OVER NRN MANITOBA WITH A FRONT EXTENDING TO THE SE INTO LAKE SUPERIOR. MILD CONDITIONS PREVAILED ACROSS THE REGION WITH TEMPS OVERNIGHT ONLY IN THE UPPER 20S AND LOWER 30S. TODAY...PCPN WITH THE FRONTAL BOUNDARY AND ASSOCIATED ISENTROPIC LIFT IS EXPECTED TO REMAIN NORTH OF UPPER MICHIGAN. OTHERWISE...AREAS OF MID CLOUDS THIS MORNING SHOULD GIVE WAY TO CLEARING BY AFTERNOON BOOSTING LOW LEVEL MIXING AND WARMING. WITH 925 MB TEMPS CLIMBING INTO THE 3C TO 6C THIS AFTERNOON...EXPECT HIGH TEMPS TOWARD THE HIGHER END OF GUIDANCE RANGING FROM THE MID 40S TO AROUND 50 OVER MOST OF THE CWA. TONIGHT...DRY CONDITIONS WILL PREVAIL WITH SUBSIDENCE AND 700-50 MB QVECTOR PREVAILING AS THE NRN ONTARIO SHRTWV MOVES EAST OF THE AREA. AS THE SFC LOW PRES MOVES INTO QUEBEC...WINDS WILL GRADUALLY VEER TO THE NW WITH SLIGHTLY COLDER AIR MOVING IN OVERNIGHT. HOWEVER...TEMPS WILL REMAIN ABOVE NORMAL WITH MIN READINGS ONLY IN THE MID TO UPPER 20S. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 350 AM EDT MON MAR 10 2014 THE EASTERN CANADIAN TROUGH THAT HAS AFFECTED THE EASTERN CONUS FOR MUCH OF THE WINTER WILL REMAIN IN PLACE FOR THE LONG TERM PERIOD AND...FROM THE LOOKS OF THE CFS AND OTHER LONG TERM OUTLOOKS...THROUGH THE REST OF MARCH. FORTUNATELY FOR THOSE LOOKING FOR ANY SIGNS OF SPRING...WE ARE IN THE MIDST OF A WEAK DISRUPTION OF THE UPPER TROUGH BY MILDER PACIFIC AIR AND ANOTHER IS EXPECTED FOR THE END OF THE WORK WEEK. BUT THESE ARE FAIRLY SHORT LIVED AND OTHERWISE BELOW NORMAL TEMPERATURES ARE EXPECTED...ESPECIALLY WEDNESDAY AND AGAIN THIS WEEKEND INTO THE START OF NEXT WEEK. TO START THE LONG TERM PERIOD...THE CLIPPER SYSTEM THAT WILL BE MOVING NORTH OF THE CWA THIS AFTERNOON AND EVENING WILL CONTINUE EAST THROUGH QUEBEC ON TUESDAY. A STEADY SURGE OF COLD AIR WILL START MOVING SOUTHEAST ACROSS THE CWA LATE TONIGHT AND CONTINUE ALL OF THE WAY THROUGH WEDNESDAY MORNING WHEN 850MB TEMPS BOTTOM OUT AT -21C. WITH THIS STEADY COLD AIR ADVECTION AND NORTHWEST TO EVENTUALLY NORTHERLY FLOW OVER THE AREA...WOULD EXPECT HIGHS ON TUESDAY TO OCCUR DURING THE FIRST PART OF THE DAYTIME PERIOD AND THEN STEADILY FALL LATER IN THE AFTERNOON AND THROUGH THE NIGHT. WITH THE COLD AIR...IT DOES APPEAR THAT MOISTURE WILL BE ON THE INCREASE DURING THE AFTERNOON AND WHEN COMBINED WITH STEEPENING LOW LEVEL LAPSE RATES...THERE MAY BE SOME DIURNAL SNOW SHOWERS IN THE AFTERNOON. BUFKIT SOUNDINGS FROM NAM/GFS AND LOCAL WRF INDICATE THE MOISTURE BEING FAIRLY SHALLOW...SO WILL LIMIT POPS TO SLIGHT CHANCES. BIGGEST SURGE OF COLD AIR COMES DURING THE EVENING...AS ANOTHER TROUGH DROPS ACROSS THE AREA AND SHIFTS LOW LEVEL WINDS TO THE NORTHEAST. THE EXPECTED INCREASE IN LOW LEVEL MOISTURE...UPSLOPE FLOW AND SOME HEAT FLUXES OFF THE MAINLY ICE COVERED LAKE SUPERIOR SHOULD SUPPORT UPSLOPE SNOWFALL IN NORTH CENTRAL UPPER MICHIGAN. WINDS WILL BEGIN BACKING NORTHERLY DURING THE EVENING...SO ATTEMPTED TO SHOW A TRANSITION UP IN POPS DURING THAT TIME FRAME TO THE PEAK DURING THE OVERNIGHT HOURS WHEN THE FLOW BECOMES PERSISTENT OUT OF THE NORTHEAST. OVERALL THE SETUP LOOKS TO BE SIMILAR TO THIS PAST FRIDAY EVENING INTO SATURDAY MORNING...BUT ABOUT 10C COLDER ALOFT WITH A LITTLE LESS MOISTURE. THOSE COLDER TEMPERATURES WILL QUICKLY PUSH THE CLOUD LAYER OUT OF THE DGZ AND WITH INVERSION HEIGHTS ONLY 3-4KFT...WOULDN/T EXPECT SNOW AMOUNTS TO BE MUCH MORE THAN AN INCH OR TWO IN THE TRADITIONAL HIGHER TERRAIN OF MARQUETTE/BARAGA COUNTIES. THE REST OF THE AREA WILL LIKELY SEE OCCASIONAL LIGHT SNOW SHOWERS OR FLURRIES...BUT WITH LIMITED TERRAIN LIFT ACCUMULATIONS SHOULD REMAIN LIGHT. AN AREA OF HIGH PRESSURE SLIDING SOUTHEAST FROM LAKE WINNIPEG ON WEDNESDAY MORNING WILL BRING DRIER AIR INTO THE AREA AND LEAD TO BACKING WINDS TO THE NORTH THROUGH THE DAY. THIS SHOULD GRADUALLY TAPER OFF THE SNOW SHOWERS IN THE NORTH CENTRAL THROUGH THE DAY...ESPECIALLY SINCE THEY HELD ON THROUGH MUCH OF THE DAY THIS PAST SATURDAY AS NORTHEAST WINDS WEAKENED. CONTINUE TO TREND HIGHS DOWN ON WEDNESDAY SINCE MODELS ARE CONSISTENT ON VALUES IN THE UPPER SINGLE DIGITS ABOVE ZERO OVER THE NORTH AND THE LOW-MID TEENS OVER THE SOUTH. THAT SEEMS ENTIRELY REASONABLE...ESPECIALLY OVER THE NORTH CENTRAL WHERE THE CLOUDS WILL LIMIT ANY INFLUENCE OF THE WARM MARCH SUN. THE RECORD LOW HIGH TEMP FOR MARCH 12TH IS 15 DEGREES AND DURING THE DAY THAT WILL BE EASILY SURPASSED. BUT BREAKING IT WILL DEPEND ON TEMPERATURES AT MIDNIGHT...SINCE CURRENT FOREAST IS RIGHT IN THE MID TEENS AT THAT TIME. THE HIGH WILL BE QUICKLY SLIDING SOUTHEAST ACROSS THE CWA ON WEDNESDAY EVENING AND EARLY OVERNIGHT HOURS. THIS WILL ALLOW WINDS TO BECOME LIGHT AND WITH PWATS AROUND 15-20 PERCENT OF NORMAL AND CLEAR SKIES...TEMPS WILL REALLY DROP. GOING FORECAST IS IN DECENT SHAPE WITH LOWS IN THE SINGLE DIGITS BELOW ZERO OVER THE WEST HALF AND -10 TO -15 BELOW OVER THE EAST. THAT MATCHES UP WELL WITH THE GREAT PERFORMING GEM (ON RADIATIONAL COOLING NIGHTS) AND ONLY MADE MINOR ADJUSTMENTS TO SOME OF THE COLDER SPOTS. COULD BREAK A RECORD LOW AT MANISTIQUE (-7 IN 1948) AND MAYBE MUNISING (-10 IN 1926)...BUT THINK NEWBERRY/S -23 IN 1905 MAY BE OUT OF REACH. WITH THE HIGH SHIFTING EAST ON THURSDAY MORNING...AREA WILL COME UNDER ANOTHER WARM AIR ADVECTION REGIME AS A CLIPPER SYSTEM APPROACHES FROM THE NORTHWEST. THIS WILL LEAD TO RISING TEMPS OVER THE WEST LATE WEDNESDAY NIGHT AND COULD BRING SOME LIGHT PRECIPITATION TO THE WESTERN HALF OF THE CWA IN THE MORNING WITH THE STRONG/BROAD 850-700MB WAA. MODELS SEEM TO BECOMING LESS EXCITED ON QPF AMOUNTS AS IT SHIFTS EAST AND FORCING BROADENS...SO WILL CONTINUE JUST THE SLIGHT CHANCE POPS OVER THE WEST AND THEN DIMINISH AS THEY HEAD EAST IN THE AFTERNOON. THE WAA WILL LEAD TO TEMPERATURES QUICKLY REBOUNDING OVER THE WEST HALF OF THE CWA AND RISING INTO THE LOWER 30S. THE CLIPPER SYSTEM THEN DIVES SOUTHEAST ACROSS LAKE SUPERIOR AND UPPER MICHIGAN THURSDAY NIGHT INTO FRIDAY MORNING. THIS TRACK WILL LIKELY KEEP MUCH OF THE PRECIPITATION TO THE NORTH OF UPPER MICHIGAN AND HAVE CONTINUED TO SHOW THE HIGHEST POPS THERE. IF THE LOW TRACKS A LITTLE FARTHER NORTH LIKE THE TRENDS IN GEM/GFS...COULD SEE TEMPS INTO THE 40S OVER MUCH OF THE CWA. BASED OFF THE PATTERN...WILL PROBABLY SEE SOME BREEZY WESTERLY WINDS FOR A PERIOD ON FRIDAY BEHIND THE INITIAL TROUGH AND BEFORE THE COLD FRONT MOVES THROUGH DURING THE EVENING. ONCE THAT COLD FRONT MOVES THROUGH...EXPECT ANOTHER OPPORTUNITY FOR SNOW SHOWERS FRIDAY NIGHT AND A TRANSITION BACK TO BELOW NORMAL TEMPERATURES FOR THE WEEKEND (HIGHS IN THE TEENS TO MID 20S). 850MB TEMPS THIS WEEKEND WILL BE BETWEEN -12C AND -15C...SO IF ANY LARGER AREAS OF WATER OPEN UP ON LAKE SUPERIOR THERE COULD BE LIGHT LAKE EFFECT. OTHERWISE...HIGH PRESSURE WILL GRADUALLY BUILD OVER THE AREA THROUGH SUNDAY AND KEEP NORTHERLY FLOW IN PLACE. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 120 PM EDT MON MAR 10 2014 VFR CONDITIONS WILL DOMINATE AT ALL 3 TAFS SITES THROUGH TONIGHT BEFORE A COLD FRONT MOVES THROUGH TUE MORNING. ONCE THIS FRONT MOVES THROUGH...MVFR CIGS WITH SOME SHALLOW MOISTURE WILL FORM AT ALL SITES. WINDS WILL GET GUSTY THIS AFTERNOON FOLLOWING THE PASSAGE OF A LOW PRES TROF IN THE PRESENCE OF DAYTIME HEATING/MIXING. THE GUSTY WINDS WILL DIMINISH THIS EVENING WITH THE LOSS OF DAYTIME HEATING. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 500 AM EDT MON MAR 10 2014 WEST WINDS ARE EXPECTED TO INCREASE TO 20 TO 25 KNOTS BY THIS AFTERNOON AS LOW PRES MOVES TO THE NORTH OF LAKE SUPERIOR. A COLD FRONT WILL MOVE THROUGH THE AREA TUE WITH NW TO N WINDS INCREASING TO 20 TO 30 KNOTS OVER ERN LAKE SUPERIOR TUE AFTERNOON INTO TUE NIGHT. WINDS WILL DIMINISH WED INTO WED NIGHT AS HIGH PRES BUILDS OVER THE NRN LAKES. WINDS WILL REMAIN AT OR BELOW 20 KNOTS UNTIL FRIDAY WHEN ANOTHER LOW PRES SYSTEM JUST TO THE NORTH OF LAKE SUPERIOR BRINGS WEST WINDS OF 20 TO 30 KNOTS. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLB LONG TERM...SRF AVIATION...07 MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
809 AM EDT MON MAR 10 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 500 AM EDT MON MAR 10 2014 WV IMAGERY AND RUC ANALYSIS INDICATED WNW MID/UPPER LEVEL FLOW ACROSS SRN CANADA AND THE NRN CONUS WHICH HAS ALLOWED MILDER PACIFIC AIR TO SPREAD INTO THE PLAINS AND TOWARD THE WRN GREAT LAKES. A SHORTWAVE TROUGH NEAR LAKE WINNIPEG WAS MOVING INTO NW ONTARIO. AT THE SFC...LOW PRES WAS LOCATED OVER NRN MANITOBA WITH A FRONT EXTENDING TO THE SE INTO LAKE SUPERIOR. MILD CONDITIONS PREVAILED ACROSS THE REGION WITH TEMPS OVERNIGHT ONLY IN THE UPPER 20S AND LOWER 30S. TODAY...PCPN WITH THE FRONTAL BOUNDARY AND ASSOCIATED ISENTROPIC LIFT IS EXPECTED TO REMAIN NORTH OF UPPER MICHIGAN. OTHERWISE...AREAS OF MID CLOUDS THIS MORNING SHOULD GIVE WAY TO CLEARING BY AFTERNOON BOOSTING LOW LEVEL MIXING AND WARMING. WITH 925 MB TEMPS CLIMBING INTO THE 3C TO 6C THIS AFTERNOON...EXPECT HIGH TEMPS TOWARD THE HIGHER END OF GUIDANCE RANGING FROM THE MID 40S TO AROUND 50 OVER MOST OF THE CWA. TONIGHT...DRY CONDITIONS WILL PREVAIL WITH SUBSIDENCE AND 700-50 MB QVECTOR PREVAILING AS THE NRN ONTARIO SHRTWV MOVES EAST OF THE AREA. AS THE SFC LOW PRES MOVES INTO QUEBEC...WINDS WILL GRADUALLY VEER TO THE NW WITH SLIGHTLY COLDER AIR MOVING IN OVERNIGHT. HOWEVER...TEMPS WILL REMAIN ABOVE NORMAL WITH MIN READINGS ONLY IN THE MID TO UPPER 20S. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 350 AM EDT MON MAR 10 2014 THE EASTERN CANADIAN TROUGH THAT HAS AFFECTED THE EASTERN CONUS FOR MUCH OF THE WINTER WILL REMAIN IN PLACE FOR THE LONG TERM PERIOD AND...FROM THE LOOKS OF THE CFS AND OTHER LONG TERM OUTLOOKS...THROUGH THE REST OF MARCH. FORTUNATELY FOR THOSE LOOKING FOR ANY SIGNS OF SPRING...WE ARE IN THE MIDST OF A WEAK DISRUPTION OF THE UPPER TROUGH BY MILDER PACIFIC AIR AND ANOTHER IS EXPECTED FOR THE END OF THE WORK WEEK. BUT THESE ARE FAIRLY SHORT LIVED AND OTHERWISE BELOW NORMAL TEMPERATURES ARE EXPECTED...ESPECIALLY WEDNESDAY AND AGAIN THIS WEEKEND INTO THE START OF NEXT WEEK. TO START THE LONG TERM PERIOD...THE CLIPPER SYSTEM THAT WILL BE MOVING NORTH OF THE CWA THIS AFTERNOON AND EVENING WILL CONTINUE EAST THROUGH QUEBEC ON TUESDAY. A STEADY SURGE OF COLD AIR WILL START MOVING SOUTHEAST ACROSS THE CWA LATE TONIGHT AND CONTINUE ALL OF THE WAY THROUGH WEDNESDAY MORNING WHEN 850MB TEMPS BOTTOM OUT AT -21C. WITH THIS STEADY COLD AIR ADVECTION AND NORTHWEST TO EVENTUALLY NORTHERLY FLOW OVER THE AREA...WOULD EXPECT HIGHS ON TUESDAY TO OCCUR DURING THE FIRST PART OF THE DAYTIME PERIOD AND THEN STEADILY FALL LATER IN THE AFTERNOON AND THROUGH THE NIGHT. WITH THE COLD AIR...IT DOES APPEAR THAT MOISTURE WILL BE ON THE INCREASE DURING THE AFTERNOON AND WHEN COMBINED WITH STEEPENING LOW LEVEL LAPSE RATES...THERE MAY BE SOME DIURNAL SNOW SHOWERS IN THE AFTERNOON. BUFKIT SOUNDINGS FROM NAM/GFS AND LOCAL WRF INDICATE THE MOISTURE BEING FAIRLY SHALLOW...SO WILL LIMIT POPS TO SLIGHT CHANCES. BIGGEST SURGE OF COLD AIR COMES DURING THE EVENING...AS ANOTHER TROUGH DROPS ACROSS THE AREA AND SHIFTS LOW LEVEL WINDS TO THE NORTHEAST. THE EXPECTED INCREASE IN LOW LEVEL MOISTURE...UPSLOPE FLOW AND SOME HEAT FLUXES OFF THE MAINLY ICE COVERED LAKE SUPERIOR SHOULD SUPPORT UPSLOPE SNOWFALL IN NORTH CENTRAL UPPER MICHIGAN. WINDS WILL BEGIN BACKING NORTHERLY DURING THE EVENING...SO ATTEMPTED TO SHOW A TRANSITION UP IN POPS DURING THAT TIME FRAME TO THE PEAK DURING THE OVERNIGHT HOURS WHEN THE FLOW BECOMES PERSISTENT OUT OF THE NORTHEAST. OVERALL THE SETUP LOOKS TO BE SIMILAR TO THIS PAST FRIDAY EVENING INTO SATURDAY MORNING...BUT ABOUT 10C COLDER ALOFT WITH A LITTLE LESS MOISTURE. THOSE COLDER TEMPERATURES WILL QUICKLY PUSH THE CLOUD LAYER OUT OF THE DGZ AND WITH INVERSION HEIGHTS ONLY 3-4KFT...WOULDN/T EXPECT SNOW AMOUNTS TO BE MUCH MORE THAN AN INCH OR TWO IN THE TRADITIONAL HIGHER TERRAIN OF MARQUETTE/BARAGA COUNTIES. THE REST OF THE AREA WILL LIKELY SEE OCCASIONAL LIGHT SNOW SHOWERS OR FLURRIES...BUT WITH LIMITED TERRAIN LIFT ACCUMULATIONS SHOULD REMAIN LIGHT. AN AREA OF HIGH PRESSURE SLIDING SOUTHEAST FROM LAKE WINNIPEG ON WEDNESDAY MORNING WILL BRING DRIER AIR INTO THE AREA AND LEAD TO BACKING WINDS TO THE NORTH THROUGH THE DAY. THIS SHOULD GRADUALLY TAPER OFF THE SNOW SHOWERS IN THE NORTH CENTRAL THROUGH THE DAY...ESPECIALLY SINCE THEY HELD ON THROUGH MUCH OF THE DAY THIS PAST SATURDAY AS NORTHEAST WINDS WEAKENED. CONTINUE TO TREND HIGHS DOWN ON WEDNESDAY SINCE MODELS ARE CONSISTENT ON VALUES IN THE UPPER SINGLE DIGITS ABOVE ZERO OVER THE NORTH AND THE LOW-MID TEENS OVER THE SOUTH. THAT SEEMS ENTIRELY REASONABLE...ESPECIALLY OVER THE NORTH CENTRAL WHERE THE CLOUDS WILL LIMIT ANY INFLUENCE OF THE WARM MARCH SUN. THE RECORD LOW HIGH TEMP FOR MARCH 12TH IS 15 DEGREES AND DURING THE DAY THAT WILL BE EASILY SURPASSED. BUT BREAKING IT WILL DEPEND ON TEMPERATURES AT MIDNIGHT...SINCE CURRENT FOREAST IS RIGHT IN THE MID TEENS AT THAT TIME. THE HIGH WILL BE QUICKLY SLIDING SOUTHEAST ACROSS THE CWA ON WEDNESDAY EVENING AND EARLY OVERNIGHT HOURS. THIS WILL ALLOW WINDS TO BECOME LIGHT AND WITH PWATS AROUND 15-20 PERCENT OF NORMAL AND CLEAR SKIES...TEMPS WILL REALLY DROP. GOING FORECAST IS IN DECENT SHAPE WITH LOWS IN THE SINGLE DIGITS BELOW ZERO OVER THE WEST HALF AND -10 TO -15 BELOW OVER THE EAST. THAT MATCHES UP WELL WITH THE GREAT PERFORMING GEM (ON RADIATIONAL COOLING NIGHTS) AND ONLY MADE MINOR ADJUSTMENTS TO SOME OF THE COLDER SPOTS. COULD BREAK A RECORD LOW AT MANISTIQUE (-7 IN 1948) AND MAYBE MUNISING (-10 IN 1926)...BUT THINK NEWBERRY/S -23 IN 1905 MAY BE OUT OF REACH. WITH THE HIGH SHIFTING EAST ON THURSDAY MORNING...AREA WILL COME UNDER ANOTHER WARM AIR ADVECTION REGIME AS A CLIPPER SYSTEM APPROACHES FROM THE NORTHWEST. THIS WILL LEAD TO RISING TEMPS OVER THE WEST LATE WEDNESDAY NIGHT AND COULD BRING SOME LIGHT PRECIPITATION TO THE WESTERN HALF OF THE CWA IN THE MORNING WITH THE STRONG/BROAD 850-700MB WAA. MODELS SEEM TO BECOMING LESS EXCITED ON QPF AMOUNTS AS IT SHIFTS EAST AND FORCING BROADENS...SO WILL CONTINUE JUST THE SLIGHT CHANCE POPS OVER THE WEST AND THEN DIMINISH AS THEY HEAD EAST IN THE AFTERNOON. THE WAA WILL LEAD TO TEMPERATURES QUICKLY REBOUNDING OVER THE WEST HALF OF THE CWA AND RISING INTO THE LOWER 30S. THE CLIPPER SYSTEM THEN DIVES SOUTHEAST ACROSS LAKE SUPERIOR AND UPPER MICHIGAN THURSDAY NIGHT INTO FRIDAY MORNING. THIS TRACK WILL LIKELY KEEP MUCH OF THE PRECIPITATION TO THE NORTH OF UPPER MICHIGAN AND HAVE CONTINUED TO SHOW THE HIGHEST POPS THERE. IF THE LOW TRACKS A LITTLE FARTHER NORTH LIKE THE TRENDS IN GEM/GFS...COULD SEE TEMPS INTO THE 40S OVER MUCH OF THE CWA. BASED OFF THE PATTERN...WILL PROBABLY SEE SOME BREEZY WESTERLY WINDS FOR A PERIOD ON FRIDAY BEHIND THE INITIAL TROUGH AND BEFORE THE COLD FRONT MOVES THROUGH DURING THE EVENING. ONCE THAT COLD FRONT MOVES THROUGH...EXPECT ANOTHER OPPORTUNITY FOR SNOW SHOWERS FRIDAY NIGHT AND A TRANSITION BACK TO BELOW NORMAL TEMPERATURES FOR THE WEEKEND (HIGHS IN THE TEENS TO MID 20S). 850MB TEMPS THIS WEEKEND WILL BE BETWEEN -12C AND -15C...SO IF ANY LARGER AREAS OF WATER OPEN UP ON LAKE SUPERIOR THERE COULD BE LIGHT LAKE EFFECT. OTHERWISE...HIGH PRESSURE WILL GRADUALLY BUILD OVER THE AREA THROUGH SUNDAY AND KEEP NORTHERLY FLOW IN PLACE. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING) ISSUED AT 809 AM EDT MON MAR 10 2014 SINCE THE LOW LEVEL DRY AIRMASS IS EXPECTED TO REMAIN IN PLACE ...VFR CONDITIONS WILL PREDOMINATE AT ALL 3 TAFS SITES AFTER THS SHALLO RADIATION FOG DISSIPATES AT CMX. AS A LO PRES MOVES SOUTHEAST THRU ONTARIO...EXPECT A GUSTY W TO NW WIND TO DEVELOP FOLLOWING THE PASSAGE OF THE ASSOCIATED LOW PRES TROF IN THE PRESENCE OF DAYTIME HEATING/MIXING. THE MORE EXPOSED CMX LOCATION SHOULD SEE THE STRONGEST WINDS WITH LAKE BREEZE WIND COMPONENT ENHANCING THE FLOW. SINCE THE INCOMING AIRMASS WL BE DRY...VFR WX WILL CONTINUE TO BE THE RULE. THE GUSTY WINDS WILL DIMINISH THIS EVENING WITH THE LOSS OF DAYTIME HEATING. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 500 AM EDT MON MAR 10 2014 WEST WINDS ARE EXPECTED TO INCREASE TO 20 TO 25 KNOTS BY THIS AFTERNOON AS LOW PRES MOVES TO THE NORTH OF LAKE SUPERIOR. A COLD FRONT WILL MOVE THROUGH THE AREA TUE WITH NW TO N WINDS INCREASING TO 20 TO 30 KNOTS OVER ERN LAKE SUPERIOR TUE AFTERNOON INTO TUE NIGHT. WINDS WILL DIMINISH WED INTO WED NIGHT AS HIGH PRES BUILDS OVER THE NRN LAKES. WINDS WILL REMAIN AT OR BELOW 20 KNOTS UNTIL FRIDAY WHEN ANOTHER LOW PRES SYSTEM JUST TO THE NORTH OF LAKE SUPERIOR BRINGS WEST WINDS OF 20 TO 30 KNOTS. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLB LONG TERM...SRF AVIATION...JLB MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
501 AM EDT MON MAR 10 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 500 AM EDT MON MAR 10 2014 WV IMAGERY AND RUC ANALYSIS INDICATED WNW MID/UPPER LEVEL FLOW ACROSS SRN CANADA AND THE NRN CONUS WHICH HAS ALLOWED MILDER PACIFIC AIR TO SPREAD INTO THE PLAINS AND TOWARD THE WRN GREAT LAKES. A SHORTWAVE TROUGH NEAR LAKE WINNIPEG WAS MOVING INTO NW ONTARIO. AT THE SFC...LOW PRES WAS LOCATED OVER NRN MANITOBA WITH A FRONT EXTENDING TO THE SE INTO LAKE SUPERIOR. MILD CONDITIONS PREVAILED ACROSS THE REGION WITH TEMPS OVERNIGHT ONLY IN THE UPPER 20S AND LOWER 30S. TODAY...PCPN WITH THE FRONTAL BOUNDARY AND ASSOCIATED ISENTROPIC LIFT IS EXPECTED TO REMAIN NORTH OF UPPER MICHIGAN. OTHERWISE...AREAS OF MID CLOUDS THIS MORNING SHOULD GIVE WAY TO CLEARING BY AFTERNOON BOOSTING LOW LEVEL MIXING AND WARMING. WITH 925 MB TEMPS CLIMBING INTO THE 3C TO 6C THIS AFTERNOON...EXPECT HIGH TEMPS TOWARD THE HIGHER END OF GUIDANCE RANGING FROM THE MID 40S TO AROUND 50 OVER MOST OF THE CWA. TONIGHT...DRY CONDITIONS WILL PREVAIL WITH SUBSIDENCE AND 700-50 MB QVECTOR PREVAILING AS THE NRN ONTARIO SHRTWV MOVES EAST OF THE AREA. AS THE SFC LOW PRES MOVES INTO QUEBEC...WINDS WILL GRADUALLY VEER TO THE NW WITH SLIGHTLY COLDER AIR MOVING IN OVERNIGHT. HOWEVER...TEMPS WILL REMAIN ABOVE NORMAL WITH MIN READINGS ONLY IN THE MID TO UPPER 20S. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 350 AM EDT MON MAR 10 2014 THE EASTERN CANADIAN TROUGH THAT HAS AFFECTED THE EASTERN CONUS FOR MUCH OF THE WINTER WILL REMAIN IN PLACE FOR THE LONG TERM PERIOD AND...FROM THE LOOKS OF THE CFS AND OTHER LONG TERM OUTLOOKS...THROUGH THE REST OF MARCH. FORTUNATELY FOR THOSE LOOKING FOR ANY SIGNS OF SPRING...WE ARE IN THE MIDST OF A WEAK DISRUPTION OF THE UPPER TROUGH BY MILDER PACIFIC AIR AND ANOTHER IS EXPECTED FOR THE END OF THE WORK WEEK. BUT THESE ARE FAIRLY SHORT LIVED AND OTHERWISE BELOW NORMAL TEMPERATURES ARE EXPECTED...ESPECIALLY WEDNESDAY AND AGAIN THIS WEEKEND INTO THE START OF NEXT WEEK. TO START THE LONG TERM PERIOD...THE CLIPPER SYSTEM THAT WILL BE MOVING NORTH OF THE CWA THIS AFTERNOON AND EVENING WILL CONTINUE EAST THROUGH QUEBEC ON TUESDAY. A STEADY SURGE OF COLD AIR WILL START MOVING SOUTHEAST ACROSS THE CWA LATE TONIGHT AND CONTINUE ALL OF THE WAY THROUGH WEDNESDAY MORNING WHEN 850MB TEMPS BOTTOM OUT AT -21C. WITH THIS STEADY COLD AIR ADVECTION AND NORTHWEST TO EVENTUALLY NORTHERLY FLOW OVER THE AREA...WOULD EXPECT HIGHS ON TUESDAY TO OCCUR DURING THE FIRST PART OF THE DAYTIME PERIOD AND THEN STEADILY FALL LATER IN THE AFTERNOON AND THROUGH THE NIGHT. WITH THE COLD AIR...IT DOES APPEAR THAT MOISTURE WILL BE ON THE INCREASE DURING THE AFTERNOON AND WHEN COMBINED WITH STEEPENING LOW LEVEL LAPSE RATES...THERE MAY BE SOME DIURNAL SNOW SHOWERS IN THE AFTERNOON. BUFKIT SOUNDINGS FROM NAM/GFS AND LOCAL WRF INDICATE THE MOISTURE BEING FAIRLY SHALLOW...SO WILL LIMIT POPS TO SLIGHT CHANCES. BIGGEST SURGE OF COLD AIR COMES DURING THE EVENING...AS ANOTHER TROUGH DROPS ACROSS THE AREA AND SHIFTS LOW LEVEL WINDS TO THE NORTHEAST. THE EXPECTED INCREASE IN LOW LEVEL MOISTURE...UPSLOPE FLOW AND SOME HEAT FLUXES OFF THE MAINLY ICE COVERED LAKE SUPERIOR SHOULD SUPPORT UPSLOPE SNOWFALL IN NORTH CENTRAL UPPER MICHIGAN. WINDS WILL BEGIN BACKING NORTHERLY DURING THE EVENING...SO ATTEMPTED TO SHOW A TRANSITION UP IN POPS DURING THAT TIME FRAME TO THE PEAK DURING THE OVERNIGHT HOURS WHEN THE FLOW BECOMES PERSISTENT OUT OF THE NORTHEAST. OVERALL THE SETUP LOOKS TO BE SIMILAR TO THIS PAST FRIDAY EVENING INTO SATURDAY MORNING...BUT ABOUT 10C COLDER ALOFT WITH A LITTLE LESS MOISTURE. THOSE COLDER TEMPERATURES WILL QUICKLY PUSH THE CLOUD LAYER OUT OF THE DGZ AND WITH INVERSION HEIGHTS ONLY 3-4KFT...WOULDN/T EXPECT SNOW AMOUNTS TO BE MUCH MORE THAN AN INCH OR TWO IN THE TRADITIONAL HIGHER TERRAIN OF MARQUETTE/BARAGA COUNTIES. THE REST OF THE AREA WILL LIKELY SEE OCCASIONAL LIGHT SNOW SHOWERS OR FLURRIES...BUT WITH LIMITED TERRAIN LIFT ACCUMULATIONS SHOULD REMAIN LIGHT. AN AREA OF HIGH PRESSURE SLIDING SOUTHEAST FROM LAKE WINNIPEG ON WEDNESDAY MORNING WILL BRING DRIER AIR INTO THE AREA AND LEAD TO BACKING WINDS TO THE NORTH THROUGH THE DAY. THIS SHOULD GRADUALLY TAPER OFF THE SNOW SHOWERS IN THE NORTH CENTRAL THROUGH THE DAY...ESPECIALLY SINCE THEY HELD ON THROUGH MUCH OF THE DAY THIS PAST SATURDAY AS NORTHEAST WINDS WEAKENED. CONTINUE TO TREND HIGHS DOWN ON WEDNESDAY SINCE MODELS ARE CONSISTENT ON VALUES IN THE UPPER SINGLE DIGITS ABOVE ZERO OVER THE NORTH AND THE LOW-MID TEENS OVER THE SOUTH. THAT SEEMS ENTIRELY REASONABLE...ESPECIALLY OVER THE NORTH CENTRAL WHERE THE CLOUDS WILL LIMIT ANY INFLUENCE OF THE WARM MARCH SUN. THE RECORD LOW HIGH TEMP FOR MARCH 12TH IS 15 DEGREES AND DURING THE DAY THAT WILL BE EASILY SURPASSED. BUT BREAKING IT WILL DEPEND ON TEMPERATURES AT MIDNIGHT...SINCE CURRENT FOREAST IS RIGHT IN THE MID TEENS AT THAT TIME. THE HIGH WILL BE QUICKLY SLIDING SOUTHEAST ACROSS THE CWA ON WEDNESDAY EVENING AND EARLY OVERNIGHT HOURS. THIS WILL ALLOW WINDS TO BECOME LIGHT AND WITH PWATS AROUND 15-20 PERCENT OF NORMAL AND CLEAR SKIES...TEMPS WILL REALLY DROP. GOING FORECAST IS IN DECENT SHAPE WITH LOWS IN THE SINGLE DIGITS BELOW ZERO OVER THE WEST HALF AND -10 TO -15 BELOW OVER THE EAST. THAT MATCHES UP WELL WITH THE GREAT PERFORMING GEM (ON RADIATIONAL COOLING NIGHTS) AND ONLY MADE MINOR ADJUSTMENTS TO SOME OF THE COLDER SPOTS. COULD BREAK A RECORD LOW AT MANISTIQUE (-7 IN 1948) AND MAYBE MUNISING (-10 IN 1926)...BUT THINK NEWBERRY/S -23 IN 1905 MAY BE OUT OF REACH. WITH THE HIGH SHIFTING EAST ON THURSDAY MORNING...AREA WILL COME UNDER ANOTHER WARM AIR ADVECTION REGIME AS A CLIPPER SYSTEM APPROACHES FROM THE NORTHWEST. THIS WILL LEAD TO RISING TEMPS OVER THE WEST LATE WEDNESDAY NIGHT AND COULD BRING SOME LIGHT PRECIPITATION TO THE WESTERN HALF OF THE CWA IN THE MORNING WITH THE STRONG/BROAD 850-700MB WAA. MODELS SEEM TO BECOMING LESS EXCITED ON QPF AMOUNTS AS IT SHIFTS EAST AND FORCING BROADENS...SO WILL CONTINUE JUST THE SLIGHT CHANCE POPS OVER THE WEST AND THEN DIMINISH AS THEY HEAD EAST IN THE AFTERNOON. THE WAA WILL LEAD TO TEMPERATURES QUICKLY REBOUNDING OVER THE WEST HALF OF THE CWA AND RISING INTO THE LOWER 30S. THE CLIPPER SYSTEM THEN DIVES SOUTHEAST ACROSS LAKE SUPERIOR AND UPPER MICHIGAN THURSDAY NIGHT INTO FRIDAY MORNING. THIS TRACK WILL LIKELY KEEP MUCH OF THE PRECIPITATION TO THE NORTH OF UPPER MICHIGAN AND HAVE CONTINUED TO SHOW THE HIGHEST POPS THERE. IF THE LOW TRACKS A LITTLE FARTHER NORTH LIKE THE TRENDS IN GEM/GFS...COULD SEE TEMPS INTO THE 40S OVER MUCH OF THE CWA. BASED OFF THE PATTERN...WILL PROBABLY SEE SOME BREEZY WESTERLY WINDS FOR A PERIOD ON FRIDAY BEHIND THE INITIAL TROUGH AND BEFORE THE COLD FRONT MOVES THROUGH DURING THE EVENING. ONCE THAT COLD FRONT MOVES THROUGH...EXPECT ANOTHER OPPORTUNITY FOR SNOW SHOWERS FRIDAY NIGHT AND A TRANSITION BACK TO BELOW NORMAL TEMPERATURES FOR THE WEEKEND (HIGHS IN THE TEENS TO MID 20S). 850MB TEMPS THIS WEEKEND WILL BE BETWEEN -12C AND -15C...SO IF ANY LARGER AREAS OF WATER OPEN UP ON LAKE SUPERIOR THERE COULD BE LIGHT LAKE EFFECT. OTHERWISE...HIGH PRESSURE WILL GRADUALLY BUILD OVER THE AREA THROUGH SUNDAY AND KEEP NORTHERLY FLOW IN PLACE. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 123 AM EDT MON MAR 10 2014 SINCE THE LATEST SFC OBS AND 00Z RAOBS INDICATE THE LLVL AIRMASS WL REMAIN RELATIVELY DRY...EXPECT VFR CONDITIONS TO PREDOMINATE AT ALL 3 TAFS SITES THRU THIS MRNG. BEST CHC FOR SOME MVFR CONDITIONS WOULD BE AT CMX AS A LO PRES TROF SETTLES OVER THAT LOCATION AND ENHANCES LLVL CNVGC. AS A LO PRES MOVES SOUTHEAST THRU ONTARIO...EXPECT A GUSTY W TO NW WIND TO DEVELOP FOLLOWING THE PASSAGE OF ATTENDANT LO PRES TROF IN THE PRESENCE OF DAYTIME HEATING/MIXING. THE MORE EXPOSED CMX LOCATION SHOULD SEE THE STRONGEST WINDS WITH LAKE BREEZE WIND COMPONENT ENHANCING THE FLOW. SINCE THE INCOMING AIRMASS WL BE DRY...VFR WX WL BE THE RULE. THE GUSTY WINDS WL DIMINISH THIS EVNG WITH THE LOSS OF DAYTIME HEATING. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 500 AM EDT MON MAR 10 2014 WEST WINDS ARE EXPECTED TO INCREASE TO 20 TO 25 KNOTS BY THIS AFTERNOON AS LOW PRES MOVES TO THE NORTH OF LAKE SUPERIOR. A COLD FRONT WILL MOVE THROUGH THE AREA TUE WITH NW TO N WINDS INCREASING TO 20 TO 30 KNOTS OVER ERN LAKE SUPERIOR TUE AFTERNOON INTO TUE NIGHT. WINDS WILL DIMINISH WED INTO WED NIGHT AS HIGH PRES BUILDS OVER THE NRN LAKES. WINDS WILL REMAIN AT OR BELOW 20 KNOTS UNTIL FRIDAY WHEN ANOTHER LOW PRES SYSTEM JUST TO THE NORTH OF LAKE SUPERIOR BRINGS WEST WINDS OF 20 TO 30 KNOTS. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLB LONG TERM...SRF AVIATION...KC MARINE...JLB
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
352 PM EDT MON MAR 10 2014 .SYNOPSIS... AN AREA OF LOW PRESSURE WILL MOVE ACROSS THE NORTH COUNTRY TONIGHT PRODUCING A MIX OF LIGHT SNOW AND RAIN. HIGH PRESSURE THEN BUILDS BRIEFLY INTO THE AREA FOR SOME OF TUESDAY...ONLY TO BE FOLLOWED BY A COASTAL LOW THAT WILL AFFECT THE REGION WEDNESDAY INTO THURSDAY. HIGH PRESSURE FOR FRIDAY WITH A CHANCE FOR PRECIPITATION TO START THE UPCOMING WEEKEND. && .NEAR TERM /THROUGH TUESDAY/... AS OF 334 PM EDT MONDAY...STILL SEEING SOME BREAKS IN THE OVERCAST THIS AFTERNOON AHEAD OF A SFC WARM FRONT POSITIONED NEAR THE CENTRAL ADIRONDACKS. RATHER WIDE VARIATION IN TEMPERATURES RANGING FROM THE UPPER 20S/AROUND 30 FOR THE NORTHEAST KINGDOM...NORTHERN GREENS AND EASTERN VERMONT TO THE UPPER 30S AND LOW 40S THIS AFTERNOON IN THE SOUTHERN CHAMPLAIN AND SAINT LAWRENCE VALLEY AREAS. EXPECT AN INCREASE IN CLOUDS AND SOUTHERLY WINDS AS A DEVELOPING SFC LOW NOW OVER THE NORTHERN GREAT LAKES SLIDES SOUTHEASTWARD ACROSS THE NORTH COUNTRY THIS EVENING. A BURST OF LOW-LEVEL WARM AIR ADVECTION AND CYCLONIC VORTICITY ADVECTION WILL PROVIDE ENOUGH SYNOPTIC LIFT TO GENERATE WIDESPREAD LIGHT PRECIPITATION BEGINNING THIS EVENING INTO THE OVERNIGHT HOURS. CURRENT INDICATIONS ARE THAT PRECIPITATION WILL BEGIN AS SOON AS 7 PM OR SO IN THE SAINT LAWRENCE VALLEY AND TOWARDS 10 PM IN THE CHAMPLAIN VALLEY AND THE REST OF VERMONT. THIS IS REFLECTED IN PRECIPITATION PROBABILITIES BECOMING LIKELY TO CATEGORICAL WITH A GRADUAL TAPER DOWN FROM WEST TO EAST TOWARD MORNING. HI-RES MODEL REFLECTIVITY PROGS SUCH AS THE BTV WRF RUNS AND RECENT HRRR SHOW GOOD AGREEMENT WITH A STEADY BAND OF PRECIPITATION MOVING ACROSS THE NORTHERN AND EASTERN THIRD OF VERMONT AND NORTHERN NEW YORK DURING THE OVERNIGHT. THIS CLIPPER SYSTEM WILL ALSO HAVE A LITTLE MORE MOISTURE TO WORK WITH THAN LAST NIGHT...WITH QPF UP TO .20-.25" IN NORTHEAST VERMONT. THERE ARE A FEW LIMITING FACTORS FOR SNOW ACCUMULATIONS: (1) MARGINAL SFC TEMPERATURES FOR THE CHAMPLAIN AND SAINT LAWRENCE VALLEYS RESULTING IN P-TYPES OF RAIN OR RAIN/SNOW MIX FOR AT LEAST PART OF THE EVENT AND (2) LOWER THAN AVERAGE SLR`S (NEAR 10:1 THOUGH A BIT HIGHER AT ELEVATION). PRECIPITATION EXPECTED TO STAY ALL SNOW THE LONGEST ACROSS EASTERN AND NORTHEAST VERMONT WHERE GROUND TEMPS ARE SUB-FREEZING. THAT SAID...I`VE OPTED TO GO WITH SNOW ACCUMULATIONS RANGING FROM A DUSTING TO AN INCH IN THE CHAMPLAIN AND SAINT LAWRENCE VALLEYS...UP TO 2" IN NORTHEAST VERMONT...AND 2-4" FOR THE HIGHER TERRAIN INCLUDING AREAS SUCH AS JAY PEAK AND MT MANSFIELD. LOWS FROM THE MID 20S TO AROUND 30...NOT FALLING MUCH FROM CURRENT VALUES GIVEN OVERCAST SKIES. LOOKING AT SOME LINGERING SNOW SHOWERS INTO THE EARLY PART OF TUESDAY FOR THE NORTHERN GREENS AND ADIRONDACKS...BUT CONDITIONS DO BEGIN TO IMPROVE WITH WEAK SUBSIDENCE ALOFT. 850 MB TEMPERATURES FALL TO AROUND -6C TUESDAY IN THE WAKE OF THE CLIPPER SYSTEM BUT MORE SUNSHINE SHOULD ALLOW FOR HIGHS ON TUESDAY SIMILAR TO TODAY...MAINLY MID 30S TO THE LOW 40S. && .SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/... AS OF 345 PM EST MONDAY... ...SIGNIFICANT WINTER STORM WL IMPACT THE ENTIRE NORTH COUNTRY WEDS INTO THURS WITH 10 TO 20 INCHES OF SNOW POSSIBLE... WINTER STORM WATCH CONTINUES FOR THE SAINT LAWRENCE VALLEY...WHILE WATCH HAS BEEN UPGRADED TO WARNING FOR THE DACKS...CPV...CENTRAL AND NORTHERN VT. WATER VAPOR SHOWS SYSTEM OF INTEREST NOW ACRS THE NW CONUS WITH NORTHERN STREAM ENERGY STILL LOCATED ACRS NORTH/CENTRAL CANADA. THESE TWO PIECES OF ENERGY WL QUICKLY MOVE INTO THE CENTRAL CONUS BY 12Z WEDS...WITH SFC LOW PRES DEVELOPING ACRS THE OHIO VALLEY. FULL LATITUDE TROF IS EXPECTED TO DEVELOP ACRS THE EASTERN CONUS WITH 5H/7H CIRCULATIONS BECOMING CLOSED OFF ACRS EASTERN NY INTO SNE. THE COMBINATION OF A DUAL 25H JET STRUCTURE AND POTENT S/W ENERGY DIVING INTO THE TROF...WL RESULT IN RAPID INTENSIFICATION OF SYSTEM. BOTH GFS/NAM SHOW RRQ OF 120 JET LIFTING ACRS SOUTHERN CANADA WHILE LFQ OF SUB-TROPICAL JET IS STREAKING ACRS THE SOUTHERN CONUS INTO THE MID ATLANTIC STATES. THIS DUAL STRUCTURE WL PROMOTE DEEP LAYER LIFT AND RAPID CYCLOGENESIS TO OCCUR AS SFC LOW PRES TRACKS FROM NEAR PITTSBURGH PA TO CAPE COD. THE EXACT TIMING AND LOCATION OF THIS OCCURRING WL PLAY A HUGE ROLE IN THE AMOUNT OF SNOWFALL/QPF ACRS OUR CWA...IF IT OCCURS TO OUR EAST...MUCH LESS IMPACTS. THE UKMET/GEM STILL HINT AT THIS POTENTIAL...BUT HAVE BEEN TRENDING STRONGER/DEEPER. THE LATEST 12Z NAM/GFS/ECMWF SHOW THIS PHASING OCCURRING FASTER AND DEEPER THAN PREVIOUS RUNS...RESULTING IN MUCH GREATER IMPACTS ACRS OUR CWA. THIS PLACES OUR CWA IN THE FAVORABLE FRONT SIDE WAA LIFT/MOISTURE ON WEDS AND BACKSIDE DEFORMATION/UPSLOPE PRECIP ON THURSDAY. ALSO...HAVE NOTED A SLIGHTLY FURTHER NORTH TRACK IN SFC LOW ...WHICH DOES PLACE PTYPE AN ISSUE ACRS OUR EXTREME SOUTHERN CWA. BOTH NAM/GFS SHOW CRITICAL THICKNESS VALUES VERY CLOSE TO A MIX...ESPECIALLY THE 12Z GFS WITH THE 540 LINE INTO CENTRAL VT. GFS SOUNDING AT VSF SHOWS 825MB TEMP AROUND 3C...WHICH WOULD SUPPORT A MIX WITH RAIN POSSIBLE ON WEDS EVENING. WL MENTION SOME MIX ACRS OUR EXTREME SOUTHERN ZNS AND IN WSW TEXT PRODUCT. USING A BLEND BTWN THE ECMWF/GFS AND NAM SHOWS INITIAL SURGE OF WAA FGEN FORCING DEVELOPING BTWN 12Z-15Z WEDS...WITH STRONGEST 850 TO 700MB FORCING/UVVS ON 1ST PART OF THE SYSTEM OCCURRING ON WEDS AFTN/EVENING. GIVEN THE AVAILABLE MOISTURE WITH PWS SURGING ABOVE 0.50" OR 150% OF NORMAL AND STRONG DYNAMICS...THINKING SNOWFALL RATES OF 1 TO 2 INCHES PER HOUR WL BE POSSIBLE FOR A PERIOD OF TIME ON WEDS EVENING. DIFFICULT TO DETERMINE AMOUNT OF SHADOWING/IMPACTS OF TRRN ASSOCIATED WITH EAST TO NORTHEAST WINDS AT 35 TO 45 KNOTS ON WEDS. THINKING TRRN IMPACTS WL BE MINIMAL AS DIRECTION IS MORE NORTHERLY...THEN EAST...BUT WL NEED TO BE WATCHED CAREFULLY FOR SOME SHADOWING ALONG THE WESTERN SLOPES. INITIAL WAA LIFT/MOISTURE AND ASSOCIATED THERMAL PROFILES WL RESULT IN SNOW RATIOS BTWN 10 AND 14 TO 1...WITH TOTAL QPF BTWN 0.20 AND 0.50 ACRS OUR CWA...RESULTING IN A GENERAL 3 TO 8 INCHES OF SNOW. SOME HIGHER AMOUNTS NEAR 10" POSSIBLE ON THE SE UPSLOPE REGIONS OF THE GREEN MTNS FROM KILLINGTON TO STOWE AND EASTERN DACKS. THE 2ND PART IMPACTS OUR REGION LATE WEDS NIGHT INTO MOST OF THURSDAY NOW...WITH VERY FAVORABLE BACKSIDE DEFORMATION/UPSLOPE FLW. BOTH NAM/GFS SHOW GOOD RIBBON OF ENHANCED 850 TO 500MB RH...STRONG 850 TO 700MB FGEN ASSOCIATED WITH SECONDARY WARM AIR CONVEYOR ALOFT AND DEVELOPING LLVL CAA ON NORTHERLY WINDS. THIS COMBINED WITH THE SYSTEM DEEPENING AND BECOMING VERTICALLY STACKED...WL RESULT IN A SLOWER SHIFT EASTWARD AND PROLONGED UPSLOPE FLW. ADDITIONAL BACKSIDE QPF/UPSLOPE FLW QPF WL RANGE FROM 0.25" SLV/LWR CT RIVER VALLEY TO 0.50 TO 0.75"...WESTERN SLOPES/DACKS/CPV/NEK. AS GUSTY NORTH WINDS DEVELOP...STRONG LLVL CAA WL OCCUR AND OUR SNOW RATIOS ASSOCIATED WITH BACKSIDE DEFORMATION ZN WL JUMP BTWN 20 AND 30 TO 1. THE QPF COMBINED WITH HIGH FLUFF FACTOR SHOULD RESULT IN ADDITIONAL 4 TO 8 INCHES SLV/LWR CT RIVER VALLEY...6 TO 12 INCHES DACKS/NEK/CPV...AND 10 TO 16 INCHES WESTERN SLOPES. SO ADDING BOTH PARTS TOGETHER RESULTS IN A WIDESPREAD 10 TO 20 INCH EVENT WITH LOCALIZED HIGHER AMOUNTS IN THE CENTRAL/NORTHERN GREEN MTNS BY LATE THURSDAY. WATCH CONTS FOR UNCERTAINTY ACRS THE SLV...THINKING A GENERAL 6 TO 12 POSSIBLE. AS 975MB LOW PRES TRACKS INTO THE GULF OF MAINE ON WEDS NIGHT/THURSDAY ...THE PRES GRADIENT WL TIGHTEN ACRS OUR CWA...WITH VERY GUSTY NORTH WINDS ANTICIPATED. HAVE NOTED BOTH THE GFS/NAM SHOWING 925MB WINDS OF 40 TO 50 KNOTS...LATE WEDS INTO THURS...WITH WELL ALIGNED FLW ACRS THE SLV/CPV...DUE TO TRRN. THIS WL PRODUCE SFC WIND GUSTS BTWN 20 AND 30 MPH WITH AREAS OF BLOWING AND DRIFTING SNOW...ALONG WITH NEAR WHITEOUT CONDITIONS POSSIBLE AT TIMES IN THE OPEN/EXPOSED AREAS. THESE NORTH WINDS WL ALSO QUICKLY ADVECT BITTERLY COLD TEMPS INTO OUR REGION LATE WEDS INTO THURS WITH PROGGED 85H TEMPS BTWN -20 AND -24C. WL TREND TWD THE COLDEST GUIDANCE ON THURS WITH HIGHS NEAR ZERO MTNS TO SINGLES/TEENS WARMER VALLEYS. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... AS OF 315 PM EDT MONDAY...LINGERING SNOW SHOWERS/FLURRIES OVER THE MOUNTAINS OF NORTHERN VERMONT THURSDAY EVENING. OTHERWISE...DRIER CONDITIONS EXPECTED AS THE LOW DEPARTS AND SURFACE RIDGE AXIS SLIDES EAST FROM GREAT LAKES AND CRESTS OVER FORECAST AREA EARLY FRIDAY. EXPECT CLEARING SKIES WITH BRISK NORTHWEST WINDS DIMINISHING OVERNIGHT. THIS COMBINED WITH ANTICIPATED FRESH SNOWPACK SHOULD ALLOW FOR GOOD RADIATIONAL COOLING. MINS THURSDAY NIGHT GENERALLY 5 ABOVE TO 5 BELOW ZERO...EXCEPT LOWER READINGS IN THE NORMALLY COLDER MOUNTAIN LOCALES...ESPECIALLY THE ADIRONDACKS. A CLIPPER SYSTEM WILL RACE EASTWARD ACROSS CENTRAL ONTARIO INTO QUEBEC FRIDAY INTO FRIDAY NIGHT...BRINGING A CHANCE OF SNOW SHOWERS FRIDAY NIGHT. STILL CHANCE FEW SNOW SHOWERS SATURDAY AS COLD FRONT ASSOCIATED WITH THIS LOW MOVES ACROSS THE AREA. HAVE GONE WITH 30-40 POPS FOR FRIDAY NIGHT/SATURDAY. ANY SNOW ACCUMULATIONS SHOULD BE LIGHT...AND MAINLY OVER THE HIGHER TERRAIN. UPPER TROUGH OVER THE REGION SUNDAY...SO A FEW MOUNTAIN SNOW SHOWERS STILL POSSIBLE. AS FOR TEMPS...EXPECT HIGHS FRIDAY IN THE UPPER 20S AND LOWER 30S...WARMING TO THE UPPER 30S AND LOWER 40S SATURDAY...AND COOLING SEVERAL DEGREES ON SUNDAY. LARGE DIFFERENCES BETWEEN GFS AND ECMWF MONDAY. GFS INDICATING A PUSH OF ARCTIC AIR INTO REGION WHILE ECMWF HAS FORECAST AREA ON THE NORTHERN EDGE OF A STORM SYSTEM WELL TO OUR SOUTH. HAVE GONE WITH A COMPROMISE...NOT AS COLD AS THE GFS WOULD INDICATE...AND INCLUDED THE MENTION OF A 30 POP FOR SNOW SHOWERS. && .AVIATION /20Z MONDAY THROUGH SATURDAY/... THROUGH 18Z TUESDAY...MAINLY VFR CONDITIONS THIS AFTERNOON. CONDITIONS THEN DETERIORATE ONCE AGAIN THIS EVENING. LIGHT SNOW DEVELOPS AROUND 01-02Z THIS EVENING AT MSS/SLK AND 02-04Z AT THE REMAINING TAF SITES WITH NEXT CLIPPER SYSTEM. SEVERAL HOURS OF IFR CONDITIONS ARE EXPECTED TONIGHT AT ALL TAF LOCATIONS. CONDITIONS GRADUALLY IMPROVE TO MOSTLY VFR DURING TUESDAY ALTHOUGH THERE WILL BE SOME LINGERING SNOW SHOWERS AND MVFR CONDITIONS THROUGH MIDDAY...ESPECIALLY SLK/MPV. WINDS S-SW 5-10 KTS THIS AFTERNOON...BECOMING WESTERLY 8-15 KTS TUESDAY. OUTLOOK 18Z TUESDAY THROUGH SATURDAY... 18Z TUE - 12Z WED...MAINLY VFR WITH PSBL MVFR IN SNOW SHWRS. 12Z WED - 18Z THU...IFR IN MODERATE TO HEAVY SNOW DUE DEEPENING LOW PRESSURE TRACKING FROM PITTSBURGH PA WEDNESDAY MORNING INTO GULF OF MAINE THURSDAY AFTERNOON. 18Z THU - 00Z FRI...IMPROVING TO VFR. NORTH WINDS GUSTING 30 KTS. 00Z FRI - 00Z SAT...MAINLY VFR. S-SW WINDS 15-25 KTS FRIDAY AFTN. 00Z SAT - 00Z SUN...MVFR WITH PSBL IFR VSBY AT TIMES IN SNOW SHWRS. && .BTV WATCHES/WARNINGS/ADVISORIES... VT...WINTER STORM WARNING FROM 8 AM WEDNESDAY TO 8 PM EDT THURSDAY FOR VTZ001>012-016>019. NY...WINTER STORM WARNING FROM 8 AM WEDNESDAY TO 8 PM EDT THURSDAY FOR NYZ028>031-034-035. WINTER STORM WATCH FROM WEDNESDAY MORNING THROUGH THURSDAY AFTERNOON FOR NYZ026-027-087. && $$ SYNOPSIS...LOCONTO NEAR TERM...LOCONTO SHORT TERM...TABER LONG TERM...RJS AVIATION...RJS
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
334 PM EDT MON MAR 10 2014 .SYNOPSIS... AN AREA OF LOW PRESSURE WILL MOVE ACROSS THE NORTH COUNTRY TONIGHT PRODUCING A MIX OF LIGHT SNOW AND RAIN. HIGH PRESSURE THEN BUILDS BRIEFLY INTO THE AREA FOR SOME OF TUESDAY...ONLY TO BE FOLLOWED BY A COASTAL LOW THAT WILL AFFECT THE REGION WEDNESDAY INTO THURSDAY. HIGH PRESSURE FOR FRIDAY WITH A CHANCE FOR PRECIPITATION TO START THE UPCOMING WEEKEND. && .NEAR TERM /THROUGH TUESDAY/... AS OF 334 PM EDT MONDAY...STILL SEEING SOME BREAKS IN THE OVERCAST THIS AFTERNOON AHEAD OF A SFC WARM FRONT POSITIONED NEAR THE CENTRAL ADIRONDACKS. RATHER WIDE VARIATION IN TEMPERATURES RANGING FROM THE UPPER 20S/AROUND 30 FOR THE NORTHEAST KINGDOM...NORTHERN GREENS AND EASTERN VERMONT TO THE UPPER 30S AND LOW 40S THIS AFTERNOON IN THE SOUTHERN CHAMPLAIN AND SAINT LAWRENCE VALLEY AREAS. EXPECT AN INCREASE IN CLOUDS AND SOUTHERLY WINDS AS A DEVELOPING SFC LOW NOW OVER THE NORTHERN GREAT LAKES SLIDES SOUTHEASTWARD ACROSS THE NORTH COUNTRY THIS EVENING. A BURST OF LOW-LEVEL WARM AIR ADVECTION AND CYCLONIC VORTICITY ADVECTION WILL PROVIDE ENOUGH SYNOPTIC LIFT TO GENERATE WIDESPREAD LIGHT PRECIPITATION BEGINNING THIS EVENING INTO THE OVERNIGHT HOURS. CURRENT INDICATIONS ARE THAT PRECIPITATION WILL BEGIN AS SOON AS 7 PM OR SO IN THE SAINT LAWRENCE VALLEY AND TOWARDS 10 PM IN THE CHAMPLAIN VALLEY AND THE REST OF VERMONT. THIS IS REFLECTED IN PRECIPITATION PROBABILITIES BECOMING LIKELY TO CATEGORICAL WITH A GRADUAL TAPER DOWN FROM WEST TO EAST TOWARD MORNING. HI-RES MODEL REFLECTIVITY PROGS SUCH AS THE BTV WRF RUNS AND RECENT HRRR SHOW GOOD AGREEMENT WITH A STEADY BAND OF PRECIPITATION MOVING ACROSS THE NORTHERN AND EASTERN THIRD OF VERMONT AND NORTHERN NEW YORK DURING THE OVERNIGHT. THIS CLIPPER SYSTEM WILL ALSO HAVE A LITTLE MORE MOISTURE TO WORK WITH THAN LAST NIGHT...WITH QPF UP TO .20-.25" IN NORTHEAST VERMONT. THERE ARE A FEW LIMITING FACTORS FOR SNOW ACCUMULATIONS: (1) MARGINAL SFC TEMPERATURES FOR THE CHAMPLAIN AND SAINT LAWRENCE VALLEYS RESULTING IN P-TYPES OF RAIN OR RAIN/SNOW MIX FOR AT LEAST PART OF THE EVENT AND (2) LOWER THAN AVERAGE SLR`S (NEAR 10:1 THOUGH A BIT HIGHER AT ELEVATION). PRECIPITATION EXPECTED TO STAY ALL SNOW THE LONGEST ACROSS EASTERN AND NORTHEAST VERMONT WHERE GROUND TEMPS ARE SUB-FREEZING. THAT SAID...I`VE OPTED TO GO WITH SNOW ACCUMULATIONS RANGING FROM A DUSTING TO AN INCH IN THE CHAMPLAIN AND SAINT LAWRENCE VALLEYS...UP TO 2" IN NORTHEAST VERMONT...AND 2-4" FOR THE HIGHER TERRAIN INCLUDING AREAS SUCH AS JAY PEAK AND MT MANSFIELD. LOWS FROM THE MID 20S TO AROUND 30...NOT FALLING MUCH FROM CURRENT VALUES GIVEN OVERCAST SKIES. LOOKING AT SOME LINGERING SNOW SHOWERS INTO THE EARLY PART OF TUESDAY FOR THE NORTHERN GREENS AND ADIRONDACKS...BUT CONDITIONS DO BEGIN TO IMPROVE WITH WEAK SUBSIDENCE ALOFT. 850 MB TEMPERATURES FALL TO AROUND -6C TUESDAY IN THE WAKE OF THE CLIPPER SYSTEM BUT MORE SUNSHINE SHOULD ALLOW FOR HIGHS ON TUESDAY SIMILAR TO TODAY...MAINLY MID 30S TO THE LOW 40S. && .SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/... AS OF 423 PM EST MONDAY...SCT -SW GOING INTO TUESDAY WILL GIVE WAY TO DECENT DAY ACROSS THE AREA AS EXITING LOW GIVES WAY TO HIGH PRESSURE...ALBEIT FOR A SHORT TIME. ANY REMAINING -SW DURING THE DAY WILL BE MAINLY CONFINED TO HIR TRRN W/ LITTLE TO NONE IN VALLEY LOCALES. SFC HIGH PRESSURE OVER THE REGION GOING INTO TUESDAY NIGHT WILL GIVE WAY TO UPCOMING STORM SYSTEM...WHICH MDLS HAVE BEEN TRACKING ALONG THE SOUTHERN NEW ENGLAND COAST FOR PAST FEW DAYS. PRECIP SET TO BEGIN OVER AREA BY 12Z-15Z WED AS LOW TRACKS THRU APPALACHIANS AND THEN BLOSSOMS SHARPLY AS LOW MVS OFFSHORE LATER IN DAY TOWARDS EVENING HRS. MDLS SHOW QPF RANGING FROM 0.25" UP TO ALMOST 0.75" AND BASED ON TRACK...SEEING ENTIRE CWA TO SEE A LARGE DOSE OF HEAVY/WET SNOW. CURRENT RUNS FOR SNOW AMTS HAVE CWA SEEING A RANGE OF 5 TO 9 INCHES THRU 00Z THURSDAY. LOWEST TOTALS IN SLV AND HIGHEST POTENTIAL OVER SE VT BASE DON TRACK AND EXPECTED ESE FLOW OVER AREA. ADDITIONAL AMTS GOING INTO THE OVERNGT HRS. BASED ON THIS WITH MDL CONSISTENCY IN PAST FEW RUNS...WILL BE GOING WITH A WINTER STORM WATCH FOR ENTIRE REGION. TEMPS FOR THIS TIME FRAME WILL RANGE FOR HIGHS IN THE 30S TUESDAY WITH SPOT 40S...THEN MAINLY IN THE 20S FOR WEDNESDAY AS COLDER AIR WRAPS INTO AREA WITH STORM APPROACH. OVERNGT LOWS WILL RANGE FROM THE TEENS TO LOW/MID 20S. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... AS OF 315 PM EDT MONDAY...LINGERING SNOW SHOWERS/FLURRIES OVER THE MOUNTAINS OF NORTHERN VERMONT THURSDAY EVENING. OTHERWISE...DRIER CONDITIONS EXPECTED AS THE LOW DEPARTS AND SURFACE RIDGE AXIS SLIDES EAST FROM GREAT LAKES AND CRESTS OVER FORECAST AREA EARLY FRIDAY. EXPECT CLEARING SKIES WITH BRISK NORTHWEST WINDS DIMINISHING OVERNIGHT. THIS COMBINED WITH ANTICIPATED FRESH SNOWPACK SHOULD ALLOW FOR GOOD RADIATIONAL COOLING. MINS THURSDAY NIGHT GENERALLY 5 ABOVE TO 5 BELOW ZERO...EXCEPT LOWER READINGS IN THE NORMALLY COLDER MOUNTAIN LOCALES...ESPECIALLY THE ADIRONDACKS. A CLIPPER SYSTEM WILL RACE EASTWARD ACROSS CENTRAL ONTARIO INTO QUEBEC FRIDAY INTO FRIDAY NIGHT...BRINGING A CHANCE OF SNOW SHOWERS FRIDAY NIGHT. STILL CHANCE FEW SNOW SHOWERS SATURDAY AS COLD FRONT ASSOCIATED WITH THIS LOW MOVES ACROSS THE AREA. HAVE GONE WITH 30-40 POPS FOR FRIDAY NIGHT/SATURDAY. ANY SNOW ACCUMULATIONS SHOULD BE LIGHT...AND MAINLY OVER THE HIGHER TERRAIN. UPPER TROUGH OVER THE REGION SUNDAY...SO A FEW MOUNTAIN SNOW SHOWERS STILL POSSIBLE. AS FOR TEMPS...EXPECT HIGHS FRIDAY IN THE UPPER 20S AND LOWER 30S...WARMING TO THE UPPER 30S AND LOWER 40S SATURDAY...AND COOLING SEVERAL DEGREES ON SUNDAY. LARGE DIFFERENCES BETWEEN GFS AND ECMWF MONDAY. GFS INDICATING A PUSH OF ARCTIC AIR INTO REGION WHILE ECMWF HAS FORECAST AREA ON THE NORTHERN EDGE OF A STORM SYSTEM WELL TO OUR SOUTH. HAVE GONE WITH A COMPROMISE...NOT AS COLD AS THE GFS WOULD INDICATE...AND INCLUDED THE MENTION OF A 30 POP FOR SNOW SHOWERS. && .AVIATION /20Z MONDAY THROUGH SATURDAY/... THROUGH 18Z TUESDAY...MAINLY VFR CONDITIONS THIS AFTERNOON. CONDITIONS THEN DETERIORATE ONCE AGAIN THIS EVENING. LIGHT SNOW DEVELOPS AROUND 01-02Z THIS EVENING AT MSS/SLK AND 02-04Z AT THE REMAINING TAF SITES WITH NEXT CLIPPER SYSTEM. SEVERAL HOURS OF IFR CONDITIONS ARE EXPECTED TONIGHT AT ALL TAF LOCATIONS. CONDITIONS GRADUALLY IMPROVE TO MOSTLY VFR DURING TUESDAY ALTHOUGH THERE WILL BE SOME LINGERING SNOW SHOWERS AND MVFR CONDITIONS THROUGH MIDDAY...ESPECIALLY SLK/MPV. WINDS S-SW 5-10 KTS THIS AFTERNOON...BECOMING WESTERLY 8-15 KTS TUESDAY. OUTLOOK 18Z TUESDAY THROUGH SATURDAY... 18Z TUE - 12Z WED...MAINLY VFR WITH PSBL MVFR IN SNOW SHWRS. 12Z WED - 18Z THU...IFR IN MODERATE TO HEAVY SNOW DUE DEEPENING LOW PRESSURE TRACKING FROM PITTSBURGH PA WEDNESDAY MORNING INTO GULF OF MAINE THURSDAY AFTERNOON. 18Z THU - 00Z FRI...IMPROVING TO VFR. NORTH WINDS GUSTING 30 KTS. 00Z FRI - 00Z SAT...MAINLY VFR. S-SW WINDS 15-25 KTS FRIDAY AFTN. 00Z SAT - 00Z SUN...MVFR WITH PSBL IFR VSBY AT TIMES IN SNOW SHWRS. && .BTV WATCHES/WARNINGS/ADVISORIES... VT...WINTER STORM WARNING FROM 8 AM WEDNESDAY TO 8 PM EDT THURSDAY FOR VTZ001>012-016>019. NY...WINTER STORM WARNING FROM 8 AM WEDNESDAY TO 8 PM EDT THURSDAY FOR NYZ028>031-034-035. WINTER STORM WATCH FROM WEDNESDAY MORNING THROUGH THURSDAY AFTERNOON FOR NYZ026-027-087. && $$ SYNOPSIS...LOCONTO NEAR TERM...LOCONTO SHORT TERM...JN LONG TERM...RJS AVIATION...RJS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1014 PM CDT TUE MAR 11 2014 .UPDATE... ISSUED AT 1014 PM CDT TUE MAR 11 2014 ONLY A FEW MINOR UPDATES TO THE LATE EVENING FORECAST. AREA OF LOW VFR-MVFR CLOUDS CONTINUES TO DROP SOUTHEAST FROM CANADA INTO THE SOURIS RIVER VALLEY AND DEVILS LAKE BASIN. THIS IS FORECAST TO DROP SOUTHEAST INTO THE JAMES RIVER VALLEY LATE TONIGHT. A FEW WANING SHOWERS IN THE FAR SOUTH CENTRAL OTHERWISE MOSTLY CLEAR ALONG AND WEST OF THE HIGHWAY 83 CORRIDOR. WITH THE LATE EVENING UPDATED WE TRIMMED THE WESTERN EXTENT OF SNOW DROPPING SOUTH FROM CANADA...KEEPING IT CONFINED TO ONLY EASTERN PORTIONS OF CENTRAL NORTH DAKOTA. WILL HAVE TO KEEP AN EYE ON TEMPERATURES IN THE WEST AS SKIES HAVE CLEARED...BUT DEW POINT TEMPERATURES REMAIN IN THE MID 20S. LOWERED MINS IN THE FAR SOUTHWEST A COUPLE DEGREES. UPDATE ISSUED AT 727 PM CDT TUE MAR 11 2014 A WEAK INVERTED TROUGH REMAINS OVER CENTRAL NORTH DAKOTA WITH HIGH PRESSURE SITUATED TO THE WEST AND EAST OF THE TROUGH. ISOLATED DIURNAL CONVECTION OVER THE WEST CENTRAL AND SOUTHWEST WILL CONTINUE TO DIMINISH EARLY THIS EVENING. DID EXTEND ISOLATED SHOWERS INTO THE EARLY EVENING HOURS. TO THE EAST...VERY LIGHT REFLECTIVITIES IN SOUTHWEST MANITOBA WILL MOVE INTO THE FAR NORTHEAST CWA WITHING THE NEXT HOUR. OTHERWISE LITTLE IN THE WAY OF PRECIPITATION NOTED. WILL TREND LOWER ON POPS THIS EVENING OVER THE NORTHEAST CWA. LATEST 22Z HRRR AND 23Z RAP INDICATE MORE WIDESPREAD REFLECTIVITIES MID TO LATE EVENING. UPDATE ISSUED AT 518 PM CDT TUE MAR 11 2014 QUICK UPDATE TO ADD SOME LATE AFTERNOON SHOWERS ACROSS THE WEST. AN AREA OF CONVECTIVE SHOWERS HAD DEVELOPED FROM AROUND WILLISTON SOUTH THROUGH DICKINSON TO BOWMAN AND HETTINGER. THESE SHOULD DISSIPATE QUICKLY EARLY THIS EVENING. TEXT PRODUCTS HAVE BEEN SENT. && .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 339 PM CDT TUE MAR 11 2014 THE MAIN FORECAST ISSUE CONCERNING THE WEATHER IS TEMPS TONIGHT/WEDNESDAY AND LIGHT SNOW POTENTIAL EAST TONIGHT. OPERATIONALLY...THE MAIN CONCERN WILL CONTINUE TO BE THE ONGOING FLOODING FROM SNOW MELT AND ISOLATED ICE JAMES. SEE HYDRO DISCUSSION BELOW FOR ADDITIONAL DETAILS. FOR TONIGHT...THERE IS GOOD MODEL CONSENSUS TO SUPPORT LIGHT SNOW ALONG THE EASTERN FRINGE OF THE FORECAST AREA...FROM THE TURTLE MOUNTAINS THROUGH THE JAMES RIVER VALLEY. WPC QPF AND SNOW RATIOS AROUND 15:1 INDICATE SNOWFALL AMOUNTS AROUND AN INCH OR SO. THE FAMILIAR RECENT TEMPERATURE PATTERN IS EXPECTED TO CONTINUE OVERNIGHT AND WEDNESDAY...WARMER SOUTHWEST WITH NO SNOW COVER...COLDER NORTH AND EAST WITH LINGERING SNOW PACK. HAVE LEANED TOWARD THE BIAS-CORRECTED GUIDANCE WHICH IS DOING A BETTER JOB HANDLING THE SNOW COVER VARIATIONS. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 339 PM CDT TUE MAR 11 2014 ABOVE NORMAL TEMPERATURES WILL HIGHLIGHT THE MAJORITY OF THE EXTENDED FORECAST. THE 12 UTC DETERMINISTIC AND ENSEMBLE SUITE IS IN GOOD AGREEMENT ON A BROAD UPPER LEVEL RIDGE ACROSS THE WESTERN AND CENTRAL CONUS WEDNESDAY AND THURSDAY...WITH A BRIEF BREAK DOWN FRIDAY INTO SATURDAY...BEFORE THE RIDGE BUILDS AGAIN SUNDAY INTO NEXT WEEK. THIS SUPPORTS A GENERALLY DRY OVERALL PATTERN WITH ABOVE NORMAL TEMPERATURES...FOLLOWING THE WARMER EDGE OF GUIDANCE WHICH HAS VERIFIED BEST WITH THE PATTERN CHANGE TO MILDER WEATHER AND THE LOSS OF SNOW. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT) ISSUED AT 1014 PM CDT TUE MAR 11 2014 A WEAK TROUGH OF LOW PRESSURE ACROSS CENTRAL NORTH DAKOTA WILL BE THE FOCUS FOR POSSIBLE MVFR CEILINGS AND VISIBILITIES LATER THIS EVENING AND OVERNIGHT. LOW LEVEL MOISTURE CONVERGING ALONG THIS BOUNDARY IS EXPECTED TO RESULT IN MVFR CEILINGS ALONG AND EAST OF THE JAMES RIVER VALLEY. TO THE WEST OF THIS...CLEAR SKIES AND LIGHT WINDS MAY RESULT IN AREAS OF FOG. UNCERTAINTY IS HIGH AT THIS TIME ABOUT MVFR CEILINGS AND VISIBILITIES AT KMOT AND KBIS AND THEREFORE WILL LEAVE THEM OUT. HIGHER CONFIDENCE FARTHER EAST SO WILL MENTION A PERIOD OF MVFR CEILINGS AND 6SM IN FOG. IF THIS AREA SETS UP FARTHER WEST KBIS AND KMOT COULD BOTH SEE MVFR CEILINGS AND VISIBILITIES. AN UPPER LEVEL IMPULSE DROPPING SOUTH WILL ALSO PRODUCE SCATTERED SNOW SHOWERS AT KJMS LATE THIS EVENING AND OVERNIGHT. AT THIS TIME...THE SNOW IS EXPECTED TO REMAIN EAST OF KMOT AND KBIS. VFR CONDITIONS EXPECTED AT KISN AND KDIK. && .HYDROLOGY... ISSUED AT 339 PM CDT TUE MAR 11 2014 MULTIPLE FLOOD HEADLINES REMAIN IN EFFECT ACROSS THE MISSOURI BASIN. WET...DEEPLY FROZEN SOILS HAVE LEAD TO VERY HIGH RUNOFF RATES OF THE MINIMAL SNOWPACK INTO THE AREA RIVERS AND STREAMS...RESULTING IN ICE BREAK UP AND JAMS. A FLOOD WATCH HAS BEEN ISSUED FOR THE HEART RIVER NEAR MANDAN THROUGH FRIDAY EVENING. AS FLOWS INCREASE AND ICE FROM UPSTREAM MAKES ITS WAY INTO THE AREA...THE RISK OF ICE JAMS NEAR MANDAN WILL INCREASE. THE MISSOURI NEAR WILLISTON AT THIS TIME IS FORECAST TO RISE TO NEAR 21.5 FEET WEDNESDAY NIGHT...SHY OF THE 22 FT FLOOD STAGE. HOWEVER...THIS WILL HAVE TO BE CLOSELY MONITORED AS BROKEN ICE IN THE SIDNEY AND FAIRVIEW STRETCHES OF THE YELLOWSTONE RIVER ARE TRANSPORTED INTO THE WILLISTON AREA. WIDESPREAD RUNOFF...RIVER AND STREAM RISES AND ICE JAM POTENTIAL WILL INCREASE ACROSS THE SOURIS AND JAMES BASINS THROUGH THE END OF THE WEEK AS MILDER WEATHER RETURNS TO THE AREA ONCE AGAIN. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...WAA SHORT TERM...RK LONG TERM...AYD AVIATION...WAA HYDROLOGY...AYD
AREA FORECAST DISCUSSION
NWS BISMARCK ND
727 PM CDT TUE MAR 11 2014 .UPDATE... ISSUED AT 727 PM CDT TUE MAR 11 2014 A WEAK INVERTED TROUGH REMAINS OVER CENTRAL NORTH DAKOTA WITH HIGH PRESSURE SITUATED TO THE WEST AND EAST OF THE TROUGH. ISOLATED DIURNAL CONVECTION OVER THE WEST CENTRAL AND SOUTHWEST WILL CONTINUE TO DIMINISH EARLY THIS EVENING. DID EXTEND ISOLATED SHOWERS INTO THE EARLY EVENING HOURS. TO THE EAST...VERY LIGHT REFLECTIVITIES IN SOUTHWEST MANITOBA WILL MOVE INTO THE FAR NORTHEAST CWA WITHING THE NEXT HOUR. OTHERWISE LITTLE IN THE WAY OF PRECIPITATION NOTED. WILL TREND LOWER ON POPS THIS EVENING OVER THE NORTHEAST CWA. LATEST 22Z HRRR AND 23Z RAP INDICATE MORE WIDESPREAD REFLECTIVITIES MID TO LATE EVENING. UPDATE ISSUED AT 518 PM CDT TUE MAR 11 2014 QUICK UPDATE TO ADD SOME LATE AFTERNOON SHOWERS ACROSS THE WEST. AN AREA OF CONVECTIVE SHOWERS HAD DEVELOPED FROM AROUND WILLISTON SOUTH THROUGH DICKINSON TO BOWMAN AND HETTINGER. THESE SHOULD DISSIPATE QUICKLY EARLY THIS EVENING. TEXT PRODUCTS HAVE BEEN SENT. && .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 339 PM CDT TUE MAR 11 2014 THE MAIN FORECAST ISSUE CONCERNING THE WEATHER IS TEMPS TONIGHT/WEDNESDAY AND LIGHT SNOW POTENTIAL EAST TONIGHT. OPERATIONALLY...THE MAIN CONCERN WILL CONTINUE TO BE THE ONGOING FLOODING FROM SNOW MELT AND ISOLATED ICE JAMES. SEE HYDRO DISCUSSION BELOW FOR ADDITIONAL DETAILS. FOR TONIGHT...THERE IS GOOD MODEL CONSENSUS TO SUPPORT LIGHT SNOW ALONG THE EASTERN FRINGE OF THE FORECAST AREA...FROM THE TURTLE MOUNTAINS THROUGH THE JAMES RIVER VALLEY. WPC QPF AND SNOW RATIOS AROUND 15:1 INDICATE SNOWFALL AMOUNTS AROUND AN INCH OR SO. THE FAMILIAR RECENT TEMPERATURE PATTERN IS EXPECTED TO CONTINUE OVERNIGHT AND WEDNESDAY...WARMER SOUTHWEST WITH NO SNOW COVER...COLDER NORTH AND EAST WITH LINGERING SNOW PACK. HAVE LEANED TOWARD THE BIAS-CORRECTED GUIDANCE WHICH IS DOING A BETTER JOB HANDLING THE SNOW COVER VARIATIONS. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 339 PM CDT TUE MAR 11 2014 ABOVE NORMAL TEMPERATURES WILL HIGHLIGHT THE MAJORITY OF THE EXTENDED FORECAST. THE 12 UTC DETERMINISTIC AND ENSEMBLE SUITE IS IN GOOD AGREEMENT ON A BROAD UPPER LEVEL RIDGE ACROSS THE WESTERN AND CENTRAL CONUS WEDNESDAY AND THURSDAY...WITH A BRIEF BREAK DOWN FRIDAY INTO SATURDAY...BEFORE THE RIDGE BUILDS AGAIN SUNDAY INTO NEXT WEEK. THIS SUPPORTS A GENERALLY DRY OVERALL PATTERN WITH ABOVE NORMAL TEMPERATURES...FOLLOWING THE WARMER EDGE OF GUIDANCE WHICH HAS VERIFIED BEST WITH THE PATTERN CHANGE TO MILDER WEATHER AND THE LOSS OF SNOW. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING) ISSUED AT 727 PM CDT TUE MAR 11 2014 A WEAK TROUGH OF LOW PRESSURE ACROSS CENTRAL NORTH DAKOTA WILL BE THE FOCUS FOR POSSIBLE MVFR CEILINGS AND VISIBILITIES LATER THIS EVENING AND OVERNIGHT. LOW LEVEL MOISTURE CONVERGING ALONG THIS BOUNDARY IS EXPECTED TO RESULT IN MVFR CEILINGS ALONG AND EAST OF THE JAMES RIVER VALLEY. TO THE WEST OF THIS...CLEAR SKIES AND LIGHT WINDS MAY RESULT IN AREAS OF FOG. UNCERTAINTY IS HIGH AT THIS TIME ABOUT MVFR CEILINGS AND VISIBILITIES AT KMOT AND KBIS AND THEREFORE WILL LEAVE THEM OUT. HIGHER CONFIDENCE FARTHER EAST SO WILL MENTION A PERIOD OF MVFR CEILINGS AND 6SM IN FOG. IF THIS AREA SETS UP FARTHER WEST KBIS AND KMOT COULD BOTH SEE MVFR CEILINGS AND VISIBILITIES. AN UPPER LEVEL IMPULSE DROPPING SOUTH WILL ALSO PRODUCE SCATTERED SNOW SHOWERS AT KJMS LATE THIS EVENING AND OVERNIGHT. AT THIS TIME...THE SNOW IS EXPECTED TO REMAIN EAST OF KMOT AND KBIS. VFR CONDITIONS EXPECTED AT KISN AND KDIK. && .HYDROLOGY... ISSUED AT 339 PM CDT TUE MAR 11 2014 MULTIPLE FLOOD HEADLINES REMAIN IN EFFECT ACROSS THE MISSOURI BASIN. WET...DEEPLY FROZEN SOILS HAVE LEAD TO VERY HIGH RUNOFF RATES OF THE MINIMAL SNOWPACK INTO THE AREA RIVERS AND STREAMS...RESULTING IN ICE BREAK UP AND JAMS. A FLOOD WATCH HAS BEEN ISSUED FOR THE HEART RIVER NEAR MANDAN THROUGH FRIDAY EVENING. AS FLOWS INCREASE AND ICE FROM UPSTREAM MAKES ITS WAY INTO THE AREA...THE RISK OF ICE JAMS NEAR MANDAN WILL INCREASE. THE MISSOURI NEAR WILLISTON AT THIS TIME IS FORECAST TO RISE TO NEAR 21.5 FEET WEDNESDAY NIGHT...SHY OF THE 22 FT FLOOD STAGE. HOWEVER...THIS WILL HAVE TO BE CLOSELY MONITORED AS BROKEN ICE IN THE SIDNEY AND FAIRVIEW STRETCHES OF THE YELLOWSTONE RIVER ARE TRANSPORTED INTO THE WILLISTON AREA. WIDESPREAD RUNOFF...RIVER AND STREAM RISES AND ICE JAM POTENTIAL WILL INCREASE ACROSS THE SOURIS AND JAMES BASINS THROUGH THE END OF THE WEEK AS MILDER WEATHER RETURNS TO THE AREA ONCE AGAIN. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...TWH SHORT TERM...RK LONG TERM...AYD AVIATION...TWH HYDROLOGY...AYD
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
155 PM EDT MON MAR 10 2014 .SYNOPSIS... A LOW WILL MOVE ACROSS ONTARIO TODAY WITH A COLD FRONT MOVING ACROSS THE REGION LATE THIS AFTERNOON INTO THE EVENING. THIS FRONT WILL STALL ACROSS SOUTHERN OHIO AND BECOME THE TRACK FOR LOW PRESSURE THAT WILL MOVE EASTWARD ALONG THE OHIO RIVER VALLEY ON WEDNESDAY. HIGH PRESSURE WILL BRIEFLY RIDGE ACROSS THE AREA ON THURSDAY BEFORE ANOTHER LOW MOVES ACROSS ONTARIO ON FRIDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... UPDATE...CHANGES MOST AREAS TO PARTLY SUNNY SINCE CLOUDS ARE BREAKING A BIT. BELIEVE THE TREND WILL CONTINUE. ADJUSTED HOURLY TEMPS USING MODIFIED HRRR AS GUIDANCE. PREVIOUS DISCUSSION... A COUPLE PIECES OF JET ENERGY WILL MOVE ACROSS THE AREA TODAY. THE FIRST IS MOVING INTO WESTERN NY NOW WITH SOME LIFT OVER THE REGION. THE PRECIPITATION ON RADAR IS LIKELY NOT REACHING THE SURFACE BECAUSE OF THE DRY LAYER IN THE 00Z SOUNDINGS. HAVE MENTIONED SOME SPRINKLES FOR A DECENT PORTION OF THE AREA. THERE COULD BE A FEW FLURRIES ACROSS EXTREME NE OHIO INTO INLAND NW PA. LOW PRESSURE WILL THEN MOVE ACROSS ONTARIO THROUGH THE DAY WITH BREEZY CONDITIONS EXPECTED THROUGH THE AFTERNOON. AS IT APPROACHES LIFT WILL INCREASE BUT BELIEVE ANY RAIN WILL BE LIGHT. THE SOUTHWESTERLY WINDS WILL ALLOW THE REGION TO WARM NICELY WITH HIGHS ABOVE AVERAGE FOR A CHANGE. MOST LOCATIONS WILL WARM INTO THE 50S...EXCEPT WHERE THERE IS MORE SNOWPACK ACROSS THE TOLEDO AREA AND NW PA. THESE LOCATIONS WILL LIKELY REMAIN IN THE 40S. && .SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY NIGHT/... AS A WEAK FRONTAL BOUNDARY PASSES THIS EVENING WE COULD SEE SOME LAKE INDUCED LIGHT RAIN/SPRINKLES FROM THE CENTRAL LAKESHORE COUNTIES NORTHEAST INTO NW PA. IT MAY END UP JUST BEING SOME INCREASED CLOUD COVER OFF OF THE LAKES. TEMPERATURES WILL REMAIN ABOVE AVERAGE IN THE WAKE OF THE FRONT TONIGHT WITH LOWS GENERALLY IN THE MIDDLE AND UPPER 30S. TUESDAY WILL BE ANOTHER WARM DAY AS THE NEXT STORM SYSTEM TAKES SHAPE ACROSS THE SOUTHERN PLAINS. HIGHS SHOULD ONCE AGAIN REACH THE 50S FOR MOST INLAND LOCATIONS. COOLER NEAR THE LAKE WITH THE LIKELIHOOD OF A LAKE BREEZE. CLOUD COVER WILL THICKEN AND LOWER TUESDAY NIGHT AS THE LOW MOVES UP THE OHIO RIVER VALLEY. THIS SHOULD HELP TO KEEP IN SOME OF THE AFTERNOON WARMTH OVER THE REGION THROUGH MUCH OF TUESDAY NIGHT. SO WITH THAT SAID WE BELIEVE MOST OF THE REGION WILL SEE RAIN INTO THE OVERNIGHT HOURS OF TUESDAY NIGHT. HOWEVER BY SUNRISE ON WEDNESDAY THE COLDER AIR WILL BE READY TO SPREAD ACROSS THE REGION IN THE WAKE OF THE LOW. WRAP AROUND MOISTURE WILL FLOW INTO THE COLDER AIR AND PRODUCE A PERIOD OF MODERATE TO MAYBE HEAVY SNOWFALL. THE SNOW WILL MOVE INTO NW OHIO FIRST THEN SPREAD EASTWARD INTO THE AFTERNOON. AT THIS POINT IT APPEARS THAT THE HEAVIEST SWATH OF SNOW WILL BE NEAR AND NORTH OF A LINE FROM FINDLAY TO MEADVILLE. STILL ENOUGH UNCERTAINTY WITH THE TRACK AND PRECIPITATION TYPE TO KEEP US FROM PINPOINTING SNOW AMOUNTS. HOWEVER 4+ INCHES OF SNOW WILL BE POSSIBLE IN THE SWATH OF HEAVIER SNOW. MODEL TRENDS THIS WINTER SEASON HAVE BEEN TOO FAR SOUTH WITH SEVERAL OF THE STORM SYSTEMS. THIS COMBINED WITH SOME OF THE ENSEMBLE GUIDANCE INDICATING A FURTHER NORTH TRACK OF THE 850 MB LOW MAKE US THINK THAT MUCH OF THE EASTERN HALF OF THE COUNTY WARNING AREA COULD BE RAIN INTO MID MORNING ON WEDNESDAY. STAY TUNED FOR MORE DETAILS OVER THE NEXT 24 HOURS. THE LOW SHOULD BE EAST OF THE REGION BY WEDNESDAY NIGHT WITH SOME LAKE EFFECT SNOW SHOWERS LINGERING INTO AT LEAST THURSDAY MORNING. IT WILL BE MUCH COLDER WITH LOWS INTO THE SINGLE DIGITS BY THURSDAY MORNING. IF THE REGION CAN GET SOME SUNSHINE ON THURSDAY THEN MOST LOCATIONS WILL BE ABLE TO WARM INTO THE 20S. && .LONG TERM /FRIDAY THROUGH SUNDAY/... SOUTHWESTERLY FLOW AND WARM ADVECTION WILL RAMP UP ON FRIDAY AHEAD OF A LOW PRESSURE SYSTEM DROPPING SOUTH OUT OF CANADA. HIGHS SHOULD REACH 40 DEGREES AGAIN ALL AREAS...UPPER 40S IN OUR SOUTHERN COUNTIES. THE COLD FRONT ASSOCIATED WITH THE LOW WILL MOVE SOUTH ACROSS THE AREA LATE FRIDAY NIGHT BRINGING A CHANCE OF SNOW SHOWERS AND TEMPERATURES DROPPING BACK BELOW NORMAL FOR THE WEEKEND. THE INITIAL SURGE OF COLD AIR IS NOT THAT STRONG...BUT A SECONDARY PUSH WILL ARRIVE LATE IN THE WEEKEND WITH HIGHS ON MONDAY STRUGGLING TO REACH 30 DEGREES. && .AVIATION /18Z MONDAY THROUGH SATURDAY/... THE WEAK SHORT WAVE IS SOUTHEAST OF THE AREA. PATCHES OF MID CLOUDS WILL MOVE EAST BY LATE AFTERNOON. HIGH CLOUDS WILL BEGIN TO INCREASE AGAIN TONIGHT. WINDS MY LIGHTEN UP ENOUGH FOR PATCHY FOG...MAINLY ACROSS NORTHWEST OHIO EARLY TUESDAY MORNING. MID AND HIGH CLOUDS WILL INCREASE ON TUESDAY BUT CONDITIONS WILL REMAIN VFR. .OUTLOOK...NON VFR DEVELOPING TUESDAY NIGHT WITH RAIN CHANGING TO SNOW. NON-VFR WITH ACCUMULATING SNOW ON WEDNESDAY. && .MARINE... SOUTHWESTERLY WINDS OF 15 TO 20 KNOTS WILL CONTINUE ON THE LAKE TODAY...SHIFTING TO WESTERLY AND INCREASING TO 25 KNOTS ON THE EAST END OF THE LAKE WITH THE PASSAGE OF A TROUGH THIS EVENING. WINDS WILL DROP OFF BY TUESDAY MORNING TO 5 TO 15 KNOTS AS LOW PRESSURE PULLS AWAY TO THE EAST AND WEAK RIDGING BUILDS OVER THE LAKE. BY MIDWEEK WE WILL BE WATCHING A LOW PRESSURE SYSTEM THAT WILL STRENGTHEN AS IT TRACKS NORTHEAST THROUGH THE OHIO VALLEY. THERE IS SOME POTENTIAL FOR NORTH WINDS TO APPROACH GALE FORCE FOR A BRIEF PERIOD OF TIME ON WEDNESDAY AS THIS SYSTEM PASSES TO THE SOUTH BUT WILL KEEP WINDS AT 30 KNOTS IN THE FORECAST FOR NOW. UNCERTAINTY REMAINS IN THE EXACT TRACK AND STRENGTH OF THIS STORM SYSTEM. HIGH PRESSURE WILL BUILD OVER THE LAKE ON THURSDAY FOLLOWED BY INCREASING SOUTHWESTERLY FLOW AHEAD OF LOW PRESSURE APPROACHING FROM THE NORTH ON FRIDAY. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...NONE. PA...NONE. MARINE...NONE. && $$ SYNOPSIS...MULLEN NEAR TERM...TK/MULLEN SHORT TERM...MULLEN LONG TERM...KEC AVIATION...KOSARIK MARINE...KEC
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
1214 PM EDT MON MAR 10 2014 .SYNOPSIS... A LOW WILL MOVE ACROSS ONTARIO TODAY WITH A COLD FRONT MOVING ACROSS THE REGION LATE THIS AFTERNOON INTO THE EVENING. THIS FRONT WILL STALL ACROSS SOUTHERN OHIO AND BECOME THE TRACK FOR LOW PRESSURE THAT WILL MOVE EASTWARD ALONG THE OHIO RIVER VALLEY ON WEDNESDAY. HIGH PRESSURE WILL BRIEFLY RIDGE ACROSS THE AREA ON THURSDAY BEFORE ANOTHER LOW MOVES ACROSS ONTARIO ON FRIDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... UPDATE...CHANGES MOST AREAS TO PARTLY SUNNY SINCE CLOUDS ARE BREAKING A BIT. BELIEVE THE TREND WILL CONTINUE. ADJUSTED HOURLY TEMPS USING MODIFIED HRRR AS GUIDANCE. PREVIOUS DISCUSSION... A COUPLE PIECES OF JET ENERGY WILL MOVE ACROSS THE AREA TODAY. THE FIRST IS MOVING INTO WESTERN NY NOW WITH SOME LIFT OVER THE REGION. THE PRECIPITATION ON RADAR IS LIKELY NOT REACHING THE SURFACE BECAUSE OF THE DRY LAYER IN THE 00Z SOUNDINGS. HAVE MENTIONED SOME SPRINKLES FOR A DECENT PORTION OF THE AREA. THERE COULD BE A FEW FLURRIES ACROSS EXTREME NE OHIO INTO INLAND NW PA. LOW PRESSURE WILL THEN MOVE ACROSS ONTARIO THROUGH THE DAY WITH BREEZY CONDITIONS EXPECTED THROUGH THE AFTERNOON. AS IT APPROACHES LIFT WILL INCREASE BUT BELIEVE ANY RAIN WILL BE LIGHT. THE SOUTHWESTERLY WINDS WILL ALLOW THE REGION TO WARM NICELY WITH HIGHS ABOVE AVERAGE FOR A CHANGE. MOST LOCATIONS WILL WARM INTO THE 50S...EXCEPT WHERE THERE IS MORE SNOWPACK ACROSS THE TOLEDO AREA AND NW PA. THESE LOCATIONS WILL LIKELY REMAIN IN THE 40S. && .SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY NIGHT/... AS A WEAK FRONTAL BOUNDARY PASSES THIS EVENING WE COULD SEE SOME LAKE INDUCED LIGHT RAIN/SPRINKLES FROM THE CENTRAL LAKESHORE COUNTIES NORTHEAST INTO NW PA. IT MAY END UP JUST BEING SOME INCREASED CLOUD COVER OFF OF THE LAKES. TEMPERATURES WILL REMAIN ABOVE AVERAGE IN THE WAKE OF THE FRONT TONIGHT WITH LOWS GENERALLY IN THE MIDDLE AND UPPER 30S. TUESDAY WILL BE ANOTHER WARM DAY AS THE NEXT STORM SYSTEM TAKES SHAPE ACROSS THE SOUTHERN PLAINS. HIGHS SHOULD ONCE AGAIN REACH THE 50S FOR MOST INLAND LOCATIONS. COOLER NEAR THE LAKE WITH THE LIKELIHOOD OF A LAKE BREEZE. CLOUD COVER WILL THICKEN AND LOWER TUESDAY NIGHT AS THE LOW MOVES UP THE OHIO RIVER VALLEY. THIS SHOULD HELP TO KEEP IN SOME OF THE AFTERNOON WARMTH OVER THE REGION THROUGH MUCH OF TUESDAY NIGHT. SO WITH THAT SAID WE BELIEVE MOST OF THE REGION WILL SEE RAIN INTO THE OVERNIGHT HOURS OF TUESDAY NIGHT. HOWEVER BY SUNRISE ON WEDNESDAY THE COLDER AIR WILL BE READY TO SPREAD ACROSS THE REGION IN THE WAKE OF THE LOW. WRAP AROUND MOISTURE WILL FLOW INTO THE COLDER AIR AND PRODUCE A PERIOD OF MODERATE TO MAYBE HEAVY SNOWFALL. THE SNOW WILL MOVE INTO NW OHIO FIRST THEN SPREAD EASTWARD INTO THE AFTERNOON. AT THIS POINT IT APPEARS THAT THE HEAVIEST SWATH OF SNOW WILL BE NEAR AND NORTH OF A LINE FROM FINDLAY TO MEADVILLE. STILL ENOUGH UNCERTAINTY WITH THE TRACK AND PRECIPITATION TYPE TO KEEP US FROM PINPOINTING SNOW AMOUNTS. HOWEVER 4+ INCHES OF SNOW WILL BE POSSIBLE IN THE SWATH OF HEAVIER SNOW. MODEL TRENDS THIS WINTER SEASON HAVE BEEN TOO FAR SOUTH WITH SEVERAL OF THE STORM SYSTEMS. THIS COMBINED WITH SOME OF THE ENSEMBLE GUIDANCE INDICATING A FURTHER NORTH TRACK OF THE 850 MB LOW MAKE US THINK THAT MUCH OF THE EASTERN HALF OF THE COUNTY WARNING AREA COULD BE RAIN INTO MID MORNING ON WEDNESDAY. STAY TUNED FOR MORE DETAILS OVER THE NEXT 24 HOURS. THE LOW SHOULD BE EAST OF THE REGION BY WEDNESDAY NIGHT WITH SOME LAKE EFFECT SNOW SHOWERS LINGERING INTO AT LEAST THURSDAY MORNING. IT WILL BE MUCH COLDER WITH LOWS INTO THE SINGLE DIGITS BY THURSDAY MORNING. IF THE REGION CAN GET SOME SUNSHINE ON THURSDAY THEN MOST LOCATIONS WILL BE ABLE TO WARM INTO THE 20S. && .LONG TERM /FRIDAY THROUGH SUNDAY/... SOUTHWESTERLY FLOW AND WARM ADVECTION WILL RAMP UP ON FRIDAY AHEAD OF A LOW PRESSURE SYSTEM DROPPING SOUTH OUT OF CANADA. HIGHS SHOULD REACH 40 DEGREES AGAIN ALL AREAS...UPPER 40S IN OUR SOUTHERN COUNTIES. THE COLD FRONT ASSOCIATED WITH THE LOW WILL MOVE SOUTH ACROSS THE AREA LATE FRIDAY NIGHT BRINGING A CHANCE OF SNOW SHOWERS AND TEMPERATURES DROPPING BACK BELOW NORMAL FOR THE WEEKEND. THE INITIAL SURGE OF COLD AIR IS NOT THAT STRONG...BUT A SECONDARY PUSH WILL ARRIVE LATE IN THE WEEKEND WITH HIGHS ON MONDAY STRUGGLING TO REACH 30 DEGREES. && .AVIATION /12Z MONDAY THROUGH FRIDAY/... REGIONAL RADARS SHOW PRECIPITATION TRYING TO INCREASE IN COVERAGE HOWEVER LITTLE OF THIS HAS BEEN REACHING THE GROUND WITH A DRY SUB-CLOUD LAYER. A LIGHT SHOWER OR SPRINKLE IS POSSIBLE AT THE TAF SITES...MAINLY THROUGH 16Z...BEFORE DRIER AIR SPREADS IN FROM THE WEST. CONDITIONS SHOULD REMAIN VFR IN LIGHT SHOWERS WITH CEILINGS BRIEFLY DROPPING TO 4-5K FEET. OTHERWISE SOUTHWEST WINDS NEAR 10-12 KNOTS THIS MORNING WILL GUST TO 20-25 KNOTS THIS AFTERNOON... DESPITE A STRONG LOW LEVEL INVERSION WITH STRONGER WINDS ALOFT. SITES IN NE OH/NW PA MAY SEE MVFR CLOUDS DEVELOP DOWNWIND OF LAKE ERIE WITH THE PASSAGE OF A TROUGH TONIGHT. .OUTLOOK...NON VFR LIKELY TUESDAY NIGHT IN RAIN WITH ACCUMULATING SNOW ON WEDNESDAY. && .MARINE... SOUTHWESTERLY WINDS OF 15 TO 20 KNOTS WILL CONTINUE ON THE LAKE TODAY...SHIFTING TO WESTERLY AND INCREASING TO 25 KNOTS ON THE EAST END OF THE LAKE WITH THE PASSAGE OF A TROUGH THIS EVENING. WINDS WILL DROP OFF BY TUESDAY MORNING TO 5 TO 15 KNOTS AS LOW PRESSURE PULLS AWAY TO THE EAST AND WEAK RIDGING BUILDS OVER THE LAKE. BY MIDWEEK WE WILL BE WATCHING A LOW PRESSURE SYSTEM THAT WILL STRENGTHEN AS IT TRACKS NORTHEAST THROUGH THE OHIO VALLEY. THERE IS SOME POTENTIAL FOR NORTH WINDS TO APPROACH GALE FORCE FOR A BRIEF PERIOD OF TIME ON WEDNESDAY AS THIS SYSTEM PASSES TO THE SOUTH BUT WILL KEEP WINDS AT 30 KNOTS IN THE FORECAST FOR NOW. UNCERTAINTY REMAINS IN THE EXACT TRACK AND STRENGTH OF THIS STORM SYSTEM. HIGH PRESSURE WILL BUILD OVER THE LAKE ON THURSDAY FOLLOWED BY INCREASING SOUTHWESTERLY FLOW AHEAD OF LOW PRESSURE APPROACHING FROM THE NORTH ON FRIDAY. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...NONE. PA...NONE. MARINE...NONE. && $$ SYNOPSIS...MULLEN NEAR TERM...TK/MULLEN SHORT TERM...MULLEN LONG TERM...KEC AVIATION...KEC MARINE...KEC
AREA FORECAST DISCUSSION
NWS NORMAN OK
835 PM CDT TUE MAR 11 2014 .UPDATE... UPDATE TO TEMPS... WINDS OVERNIGHT... && .DISCUSSION... 12/01Z SFC ANALYSIS SHOWS THE LEADING WIND SHIFT OF THE COLD FRONT HAS FINALLY CLEARED SOUTH CENTRAL OKLAHOMA. GUSTY N/NW WINDS HAVE SPREAD ACROSS ALL OF CENTRAL AND WRN OK... AND WRN N TX. SUSTAINED WINDS OF 25 TO 30 MPH... WITH GUSTS 35 TO 40 WILL CONTINUE THROUGH THE EARLY MORNING HOURS. THIS IS BASED ON UPSTREAM OBS... WHERE WINDS HAVE REMAINED STOUT ACROSS WRN KS... SUSTAINED 3O TO 35... GUSTING 40 TO 50 MPH. THIS IS SUPPORTED BY THE STRONG PRESSURE CHANGES BEHIND THE FRONT... 3HR PRESSURE CHANGES FROM THE RAP AND H-TRIP SHOW 5 TO 8MB CHANGES ACROSS THE REGION... NOT TO MENTION 0-1KM LAPSE RATES OF 7 TO 9 C/KM. THE STRONGEST SIGNAL EXISTS THROUGH 06Z... WHEN WINDS WILL SLOWLY EASE... WITH SUSTAINED WINDS OF 15 TO 25... AND GUSTS 25 TO 30 MPH THROUGH SUNRISE. WINDS WILL REMAIN OUT OF THE NORTH AND BREEZY THROUGH THE EARLY AFTN WEDNESDAY. ALSO ADJUSTED TEMPS... AS LOCATIONS ACROSS NWRN OK HAVE DROPPED INTO THE MID 40S A TAD FASTER THAN EARLIER EXPECTED. JTK && .PRELIMINARY POINT TEMPS/POPS... OKLAHOMA CITY OK 34 54 30 66 / 10 0 0 0 HOBART OK 33 56 30 66 / 10 0 0 0 WICHITA FALLS TX 37 58 32 68 / 0 10 0 0 GAGE OK 30 53 26 67 / 10 0 0 0 PONCA CITY OK 33 53 27 67 / 10 0 0 0 DURANT OK 38 56 35 66 / 0 10 0 0 && .OUN WATCHES/WARNINGS/ADVISORIES... OK...WIND ADVISORY UNTIL 7 AM CDT WEDNESDAY FOR OKZ004>048-050>052. TX...WIND ADVISORY UNTIL 7 AM CDT WEDNESDAY FOR TXZ083>090. && $$ 17/04
AREA FORECAST DISCUSSION...UPDATED
NWS CORPUS CHRISTI TX
1242 AM CDT MON MAR 10 2014 .DISCUSSION...UPDATED FOR THE 06Z AVIATION DISCUSSION. && .AVIATION...MIXTURE OF IFR/MVFR THROUGH MID MORNING...WITH POCKETS OF VFR AT TIMES FOR LRD-ALI-CRP...MAINTAINING A MVFR CONDITIONS THROUGH THE REST OF THE TAF PERIOD. SHOULD MAINTAIN MOSTLY VFR AROUND VCT WITH PERIODS OF MVFR POSSIBLE. UPPER LOW WILL SWING EAST THROUGH MONDAY WITH VCSH EXPECTED THROUGH MUCH OF THE TAF PERIOD...WITH THUNDER POSSIBLE DURING THE AFTERNOON AS THE UPPER LOW TREKS OVERHEAD. SHOULD SEE A PERIOD OF QUIET ACTIVITY BETWEEN 12Z-18Z. CLEARING SHOULD DEVELOP LATE IN THE TAF PERIOD FROM WEST TO EAST. WINDS WILL MAINTAIN A 5-10KT NORTHERLY FLOW THROUGH MUCH OF THE DAY TAKING ON AN EASTERLY COMPONENT DURING THE LATE AFTN/EVNG. && .PREV DISCUSSION... /ISSUED 922 PM CDT SUN MAR 9 2014/ DISCUSSION...NEWEST 00Z NAM12 AND HRRR COMING IN DRIER OVERNIGHT... WITH BULK OF PRECIP SOUTH OF THE AREA WITH LEAD SHORTWAVE. HOWEVER... BEGINNING TO SEE AXIS OF WAA INCREASING FROM BROOKS NORTHWEST INTO WEBB COUNTY AND WIDELY SCATTERED SHOWERS AND PATCHY RAIN DEVELOPING. IN ADDITION...ELEVATED SHOWERS SEEN SOUTHWEST OF WEBB COUNTY ACROSS TAMPAULIPAS AND NUEVO LEON MEXICO MOVING NORTHEAST. FOR NOW WILL LEAVE POPS AS IS...WITH MAIN CHANCES OVERNIGHT SOUTH AND WEST OF I-37 AND LOW TO NO CHANCES NORTHEAST OF I-37. MODEST ELEVATED INSTABILITY MAY LEAD TO ISOLATED THUNDER. DID MAKE SOME CHANGES TO TEMPS OVERNIGHT...WITH MOST LOCATIONS ACROSS THE COASTAL BEND HOLDING IN THE LOWS 50S...AND ACROSS THE WESTERN CWA HOLDING IN THE UPPER 40S TO EVEN RISING TO AROUND 50. AFTER A POSSIBLE LULL IN PRECIP MONDAY MORNING...STILL ON TRACK FOR MAIN FORCING WITH APPROACHING UPPER LEVEL LOW TO SPREAD INTO WESTERN CWA MONDAY AFTERNOON...WITH PRECIP CHANCES DEVELOPING ACROSS THE RIO GRANDE PLAINS AND WESTERN BRUSH COUNTRY...THEN MOVING EAST INTO THE EASTERN BRUSH COUNTRY...VICTORIA CROSSROADS...AND COASTAL PLAINS LATE MONDAY AFTERNOON AND EVENING. PREV DISCUSSION... /ISSUED 632 PM CDT SUN MAR 9 2014/ DISCUSSION...UPDATE FOR 00Z AVIATION DISCUSSION. AVIATION...MIX OF MVFR/IFR VSBYS/CIGS NEXT 24 HRS ALONG WITH PRECIP AT TIMES. CIGS ARE PROG TO FLUCTUATE BETWEEN LOW END MVFR AND IFR THIS EVENING /MAY PREVAIL AT MVFR LONGER AT KCRP AND KVCT/. SHRA WILL BE POSSIBLE THIS EVENING AT PRIMARILY KLRD/KALI/KCOT WITH PERHAPS BETTER AREAL COVERAGE BETWEEN APPROX 6Z TO 10Z...ALSO EXPANDING CLOSER TO KCRP B/W 6Z TO 10Z AS WELL. VSBYS/CIGS SHOULD LOWER TO IFR DRNG PRECIP /IF NOT AT IFR ALREADY/ WITH BRIEF LIFR VSBYS POSSIBLE IF PRECIP IS HEAVY ENOUGH. KVCT IS CURRENTLY XPCTD TO REMAIN DRY TONIGHT...FOR THE MOST PART. A MORE PRONOUNCED LULL IN PRECIP MAY EXIST AT ALL TERMINALS FROM LATE NIGHT THRU THE MRNG HRS MONDAY...BUT PERSISTENT MVFR/IFR VSBYS/CIGS WILL PREVAIL. AN ADDITIONAL ROUND OF SHRA AND PERHAPS TSRA XPCTD TO DVLP VCNTY KLRD/KCOT MIDDAY/EARLY AFTN MONDAY AND THEN SPREAD EWRD DRNG THE AFTN. HAVE MENTION OF PRECIP AGAIN FOR ALL TERMINALS MON AFTN. GENERALLY LIGHT NNWRLY WINDS XPCTD THRU THE TAF PERIOD...SHIFTNG SLIGHTLY MORE NERLY ON MONDAY. AMENDMENTS TO TAFS MAY BE REQUIRED THRU THE TAF PERIOD BASED OFF FUTURE RADAR RETURNS AND PRECIP DVLPMNT. && .PRELIMINARY POINT TEMPS/POPS... CORPUS CHRISTI 52 76 55 65 45 / 60 10 10 0 10 VICTORIA 52 77 52 63 40 / 60 10 10 0 10 LAREDO 51 86 55 69 44 / 30 10 10 0 0 ALICE 50 80 53 66 42 / 50 10 10 0 10 ROCKPORT 54 73 55 65 47 / 70 10 10 0 10 COTULLA 48 83 52 66 40 / 30 10 10 0 0 KINGSVILLE 51 78 55 65 43 / 50 10 10 0 10 NAVY CORPUS 54 74 56 65 49 / 60 10 10 0 10 && .CRP WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...NONE. && $$ CB/85...AVIATION
FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION
VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP (ALL LOWER CASE)
AREA FORECAST DISCUSSION
NWS SPOKANE WA
212 PM PDT Mon Mar 10 2014 .SYNOPSIS... Rain and snow will be ending overnight Monday. Quieter weather is expected through Thursday. A weak weather front will bring light rain to the area on Friday, with another chance of rain late Sunday into next Monday. && .DISCUSSION... Tonight...cold pool and its associated instability located behind a passing cold front all exit to the southeast and east tonight. Small scale triggers rotating around the edges of a small scale low pressure area nested in this same cooler air will act as triggers. Additionally there is an increase in instability due to surface heating allowed by sun breaks across parts of the lowlands between the east side of the Cascades and the Idaho Panhandle. For all these reasons and a number of HRRR model runs depicting just such a scenario the forecast holds onto showers along with very low wet bulb zero heights allowing for a typical spring rain/snow/graupel/soft-hail mix of precipitation for mid-slope down to valley and lowland locations with the expectation that any accumulation associated with most intense convective cells will be on the order of minutes rather than hours if at all. Thunderstorm mention remains southeast third of Washington and southern half of North Idaho into early evening with idea that they will be weak, low topped, single or multicell type with potential to produce heavy rain and small soft hail/collapsed snow and gusty wind. Storm motion should be southeast at about 25-35 mph. /Pelatti Tuesday through next Monday: High pressure builds into the area on Tuesday for drier conditions. We will likely see some late night/morning fog and low clouds in the valleys, but otherwise should be nice weather. A minor weather system clips by to our north on Wednesday evening but we don`t expect much weather from this, other than some perhaps some mountain wind. The next real good chance of precipitation arrives on Friday. This system has a decent moisture tap. But the westerly flow will keep the precipitation largely confined to the Cascades and Panhandle mountains. ECMWF is slightly slower and wetter than the GFS. Snow levels will remain high (6000` south, 5000` north) so there will be little if any impact from this system. Does not look like enough rain to cause any flooding concerns. The weather system on it`s heels looks a little more formidable. This wave has a narrow but well-defined moisture plume associated with it. Initially it looks impressive with heavy rain pointed into Vancouver Island and NW Washington. But as it moves eastward, the GFS model spins up a low along this front well to our south (west of San Francisco). This cuts off the moisture supply and we are left with a dying frontal passage. The ECMWF meanwhile doesn`t show this, and has a more consolidated wet front moving through on Sunday night. Temperatures ahead of this front have the potential to be the warmest of the season so far, nearing 60F in the Spokane area. But it won`t take much change in the timing to render a cooler and wetter day for Sunday than currently forecast. Snow levels will be very high (7000-8000`) so the passes will be all rain. The snow levels lower by Monday morning and continue to lower during the day. RJ && .AVIATION... 18Z TAFS: A wet cold front has passed through a good portion of the aviation area and behind it is a smaller low pressure system that utilizing the unstable and moist atmosphere behind it to keep convective showers and perhaps a few thunderstorms going through a good part of the day and early evening...precipitation in the form of rain and non accumulating snow and/or soft hail may occur near more intense convection and produce IFR ceilings at times. This activity will translate to the south and east and exit majority of the aviation area near 2Z Tuesday which will then allow for improvement with increasing ceilings and decreased cloud cover and wind with VFR conditions more prevalent. /Pelatti && .PRELIMINARY POINT TEMPS/POPS... Spokane 30 48 27 53 32 55 / 20 0 0 0 0 0 Coeur d`Alene 29 47 26 52 30 54 / 20 0 0 0 0 0 Pullman 32 48 28 54 34 55 / 70 0 0 0 0 0 Lewiston 35 54 33 60 36 62 / 60 0 0 0 0 0 Colville 29 53 26 54 27 55 / 20 0 0 0 0 0 Sandpoint 28 45 24 47 28 50 / 20 0 0 0 10 10 Kellogg 30 45 29 49 31 50 / 60 10 0 0 0 0 Moses Lake 32 55 30 57 33 60 / 10 0 0 0 0 0 Wenatchee 32 53 32 55 33 57 / 0 0 0 0 0 0 Omak 28 52 28 53 30 56 / 0 0 0 0 0 0 && .OTX WATCHES/WARNINGS/ADVISORIES... ID...None. WA...None. && $$
AREA FORECAST DISCUSSION
NWS SPOKANE WA
1103 AM PDT Mon Mar 10 2014 .SYNOPSIS... Another wet day for southeastern Washington and north Idaho is expected today...with showers and possibly a few thunderstorms over much of eastern Washington. Flooding once again may be an issue with this very wet storm. Snow levels will remain high enough to not pose a significant threat to any passes or higher elevation routes. High pressure will then build in after today for drier and mild conditions. Following this dry period will be an increased threat of valley rain and mountain snow beginning Friday. && .DISCUSSION... 2nd update this morning to cool todays forecast max temperatures a few degrees based primarily on the expectation of cooling produced by the convection addressed in the earlier update. Additionally the mention of non accumulating snow over most locations mid-slope down to valleys is utilized to address the soft hail or collapsed snowflakes produced by the convection. Discussion concerning earlier update involving increased pops and QPF remains below in the 2nd paragraph. Increased pops with a morning update primarily based on how the past two to three HRRR model runs have been depicting a mesoscale low circulation centered in Eastern Washington this morning, which is behind the cloud shield associated with a larger low pressure system, is expected to act as a lifting trigger. It will utilized the cold pool instability over the area today and into this early evening and promote continued showers and possibly some thunderstorms during the early parts of the day. Storm motion of any afternoon/early evening thunderstorms that form should take them to the southeast at about 25-35 mph. The type of thunderstorms that may occur are the weak, low topped, single or multicell type, that could produce heavy rain and small soft hail but the gusty wind due to the quick storm motion would be the bigger nuisance. /Pelatti && .AVIATION... 18Z TAFS: A wet cold front has passed through a good portion of the aviation area and behind it is a smaller low pressure system that utilizing the unstable and moist atmosphere behind it to keep convective showers and perhaps a few thunderstorms going through a good part of the day and early evening...precipitation in the form of rain and non accumulating snow and/or soft hail may occur near more intense convection and produce IFR ceilings at times. This activity will translate to the south and east and exit majority of the aviation area near 2Z Tuesday which will then allow for improvement with increasing ceilings and decreased cloud cover and wind with VFR conditions more prevalent. /Pelatti && .PRELIMINARY POINT TEMPS/POPS... Spokane 48 30 46 27 51 32 / 100 20 0 0 0 0 Coeur d`Alene 47 29 45 26 51 29 / 100 20 0 0 0 0 Pullman 48 32 47 30 53 33 / 100 40 0 0 0 0 Lewiston 52 35 53 33 59 36 / 100 50 0 0 0 0 Colville 51 29 54 26 54 28 / 100 20 0 0 0 0 Sandpoint 47 28 44 25 47 27 / 100 20 0 0 0 10 Kellogg 44 30 46 29 50 31 / 100 40 10 0 0 0 Moses Lake 58 32 53 30 55 32 / 100 10 0 0 0 0 Wenatchee 55 32 52 32 54 34 / 100 0 0 0 0 0 Omak 55 28 50 28 52 30 / 70 0 0 0 0 0 && .OTX WATCHES/WARNINGS/ADVISORIES... ID...None. WA...None. && $$
AREA FORECAST DISCUSSION
NWS SPOKANE WA
854 AM PDT Mon Mar 10 2014 .SYNOPSIS... Another wet day for southeastern Washington and north Idaho is expected today...with showers and possibly a few thunderstorms over much of eastern Washington. Flooding once again may be an issue with this very wet storm. Snow levels will remain high enough to not pose a significant threat to any passes or higher elevation routes. High pressure will then build in after today for drier and mild conditions. Following this dry period will be an increased threat of valley rain and mountain snow beginning Friday. && .DISCUSSION... 2nd update this morning to cool todays forecast max temperatures a few degrees based primarily on the expectation of cooling produced by the convection addressed in the earlier update. Additionally the mention of non accumulating snow over most locations mid-slope down to valleys is utilized to address the soft hail or collapsed snowflakes produced by the convection. Discussion concerning earlier update involving increased pops and QPF remains below in the 2nd paragraph. Increased pops with a morning update primarily based on how the past two to three HRRR model runs have been depicting a mesoscale low circulation centered in Eastern Washington this morning, which is behind the cloud shield associated with a larger low pressure system, is expected to act as a lifting trigger. It will utilized the cold pool instability over the area today and into this early evening and promote continued showers and possibly some thunderstorms during the early parts of the day. Storm motion of any afternoon/early evening thunderstorms that form should take them to the southeast at about 25-35 mph. The type of thunderstorms that may occur are the weak, low topped, single or multicell type, that could produce heavy rain and small soft hail but the gusty wind due to the quick storm motion would be the bigger nuisance. /Pelatti && .AVIATION... 12Z TAFS: The first 6-8 hours of the forecast period will feature widespread MVFR ceilings and vis in -RA over the eastern TAF sites as a moist occluded front transits the region. The KMWH and KEAT TAF sites will be largely skipped by this weather system for mainly VFR conditions. After 18Z-20Z steady pcpn will taper off to scattered to numerous showers. Instability generated by the passage of a cool upper trough this afternoon will create a risk of isolated TSRA east of a line from KOMK to KALW. Conditions will improve to mainly VFR but a chance of brief MVFR ceilings in shower cores. Beginning after 00Z and continuing through the end of the TAF period dry continental air will invade the region and bring clearing skies with VFR conditions to all TAF sites. /MJF && .PRELIMINARY POINT TEMPS/POPS... Spokane 48 30 46 27 51 32 / 100 20 0 0 0 0 Coeur d`Alene 47 29 45 26 51 29 / 100 20 0 0 0 0 Pullman 48 32 47 30 53 33 / 100 40 0 0 0 0 Lewiston 52 35 53 33 59 36 / 100 50 0 0 0 0 Colville 51 29 54 26 54 28 / 100 20 0 0 0 0 Sandpoint 47 28 44 25 47 27 / 100 20 0 0 0 10 Kellogg 44 30 46 29 50 31 / 100 40 10 0 0 0 Moses Lake 58 32 53 30 55 32 / 100 10 0 0 0 0 Wenatchee 55 32 52 32 54 34 / 100 0 0 0 0 0 Omak 55 28 50 28 52 30 / 70 0 0 0 0 0 && .OTX WATCHES/WARNINGS/ADVISORIES... ID...None. WA...None. && $$
AREA FORECAST DISCUSSION
NWS SPOKANE WA
832 AM PDT Mon Mar 10 2014 .SYNOPSIS... Another wet day for southeastern Washington and north Idaho is expected today...with showers and possibly a few thunderstorms over much of eastern Washington. Flooding once again may be an issue with this very wet storm. Snow levels will remain high enough to not pose a significant threat to any passes or higher elevation routes. High pressure will then build in after today for drier and mild conditions. Following this dry period will be an increased threat of valley rain and mountain snow beginning Friday. && .DISCUSSION... Increased pops with a morning update primarily based on how the past two to three HRRR model runs have been depicting a mesoscale low circulation centered in Eastern Washington this morning, which is behind the cloud shield associated with a larger low pressure system, is expected to act as a lifting trigger. It will utilized the cold pool instability over the area today and into this early evening and promote continued showers and possibly some thunderstorms during the early parts of the day. Storm motion of any afternoon/early evening thunderstorms that form should take them to the southeast at about 25-35 mph. The type of thunderstorms that may occur are the weak, low topped, single or multicell type, that could produce heavy rain and small soft hail but the gusty wind due to the quick storm motion would be the bigger nuisance. /Pelatti && .AVIATION... 12Z TAFS: The first 6-8 hours of the forecast period will feature widespread MVFR ceilings and vis in -RA over the eastern TAF sites as a moist occluded front transits the region. The KMWH and KEAT TAF sites will be largely skipped by this weather system for mainly VFR conditions. After 18Z-20Z steady pcpn will taper off to scattered to numerous showers. Instability generated by the passage of a cool upper trough this afternoon will create a risk of isolated TSRA east of a line from KOMK to KALW. Conditions will improve to mainly VFR but a chance of brief MVFR ceilings in shower cores. Beginning after 00Z and continuing through the end of the TAF period dry continental air will invade the region and bring clearing skies with VFR conditions to all TAF sites. /MJF && .PRELIMINARY POINT TEMPS/POPS... Spokane 52 30 46 27 51 32 / 100 20 0 0 0 0 Coeur d`Alene 50 29 45 26 51 29 / 100 20 0 0 0 0 Pullman 49 32 47 30 53 33 / 100 40 0 0 0 0 Lewiston 56 35 53 33 59 36 / 100 50 0 0 0 0 Colville 53 29 54 26 54 28 / 100 20 0 0 0 0 Sandpoint 47 28 44 25 47 27 / 100 20 0 0 0 10 Kellogg 44 30 46 29 50 31 / 100 40 10 0 0 0 Moses Lake 60 32 53 30 55 32 / 100 10 0 0 0 0 Wenatchee 58 32 52 32 54 34 / 100 0 0 0 0 0 Omak 56 28 50 28 52 30 / 70 0 0 0 0 0 && .OTX WATCHES/WARNINGS/ADVISORIES... ID...None. WA...None. && $$
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1041 PM CDT TUE MAR 11 2014 .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 309 PM CDT TUE MAR 11 2014 THE MAIN FOCUS THROUGH TOMORROW IS WITH HOW FAST THE BAND OF PRECIPITATION SHIFTS TO THE SOUTH TONIGHT FOLLOWED BY SNOW SHOWER CHANCES TOMORROW MORNING ALONG WITH HOW COLD IT WILL BE. SURFACE/LOW LEVEL TEMPERATURES PROVED TO BE A TAD TOO WARM TODAY TO CAUSE MUCH IF ANY SNOW TO DEVELOP ALONG THE BAND OF PRECIPITATION. 11.17Z RAP SOUNDINGS CONTINUE TO SHOW THAT THE LOW LEVELS SHOULD STAY WARM ENOUGH INTO THIS EVENING TO MAINLY YIELD RAIN WITH A BRIEF TRANSITION TO SNOW ON THE BACK/NORTH SIDE OF THE BAND. THE 17.12Z HRRR/RAP SHOW THIS BAND GETTING SOUTH OF DUBUQUE BY MID EVENING. AS A DEEPENING SURFACE LOW TRACKS TO THE SOUTHEAST OF THE REGION OVERNIGHT INTO TOMORROW MORNING...AN INVERTED SURFACE TROUGH WILL ROTATE FROM EAST TO WEST ACROSS THE REGION AS A SHORT WAVE MID LEVEL TROUGH DROPS DOWN FROM ONTARIO. WITH COLDER AIR MOVING IN WITH THIS TROUGH A SATURATED LAYER SHOULD DEVELOP IN THE ICE NUCLEATION ZONE BELOW -8C WITH JUST ENOUGH LIFT FROM THE SURFACE TROUGH TO PRODUCE SOME SNOW SHOWERS. 11.12Z WRF-ARW/NMM REFLECTIVITY GUIDANCE SHOWS A BAND OF SNOW SHOWERS DEVELOPING IN EASTERN WISCONSIN OVERNIGHT AND TRACKING TO THE SOUTHWEST THROUGH THE REGION TOMORROW MORNING. SUBSIDENCE THEN TAKES OVER AND SHOULD HELP TO CLEAR SKIES OUT A BIT GOING INTO THE AFTERNOON...BUT TEMPERATURES WILL STRUGGLE TO CLIMB MUCH WITH 850MB TEMPERATURES AROUND -15C. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 309 PM CDT TUE MAR 11 2014 THE NEXT CHANCE FOR SOME LIGHT SNOW COMES IN ON WEDNESDAY NIGHT/EARLY THURSDAY MORNING AS A RIDGE OF HIGH PRESSURE PUSHES TO THE EAST AND SOME LOW LEVEL WARM AIR ADVECTION SWINGS THROUGH THE REGION. THERE ARE SOME DIFFERING OPINIONS BETWEEN THE 11.12Z NAM/GFS/ECMWF/GEM WITH THIS BAND AND HOW STRONG THE WAA WILL BE. THE GFS IS THE FASTEST WITH HAVING THE SNOW COME IN ON WEDNESDAY EVENING WHILE THE NAM IS A TAD SLOWER AND STRONGER WITH THE WAA AND PRODUCES A LITTLE MORE QPF. THE ECMWF/GEM ARE BOTH MUCH WEAKER WITH THIS SYSTEM AND HARDLY SHOW ANY QPF AT ALL...SO THERE IS SOME UNCERTAINTY WITH WHETHER ANYTHING WILL OCCUR FROM THIS. COBB DATA FROM THE GFS/NAM WOULD SAY A HALF INCH OF ACCUMULATION OR LESS IF THE SNOW DOES OCCUR. TEMPERATURES WILL CLIMB BACK TOWARD NORMAL THURSDAY WITH SOUTHWESTERLY SURFACE WINDS. A WEAK COLD FRONT WILL COME THROUGH ON FRIDAY THOUGH TEMPERATURES SHOULD NOT DROP MUCH UNTIL THE WEEKEND COMES AND NORTHWESTERLY FLOW ALOFT SETS UP. REMOVED THE CHANCES FOR PRECIPITATION ON SUNDAY AS IT LOOKS LIKE THE SHORT WAVE TROUGH DIVING SOUTH OUT OF SOUTH CENTRAL CANADA WILL RUN TO THE WEST OF THE REGION. THE BETTER CHANCES APPEAR TO COME ON TUESDAY AS THE 11.12Z ECMWF BRINGS A SYSTEM OUT OF THE PLAINS AND TO THE SOUTH OF THE UPPER MISSISSIPPI RIVER VALLEY. THE 11.12Z GFS IS MUCH FURTHER TO THE NORTH WITH THIS SYSTEM AND WOULD BRING WARMER AIR INTO THE REGION. QUITE A BIT OF UNCERTAINTY OUT THERE...BUT ENOUGH TO WARRANT SOME CHANCES FOR PRECIPITATION ON TUESDAY. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT) ISSUED AT 1041 PM CDT TUE MAR 11 2014 CLOUDS EXTENDING ACROSS NORTHERN MINNESOTA...NORTHERN WISCONSIN AND UPPER MICHIGAN CONTINUE TO MARCH SOUTHWARD TOWARDS THE TAF SITES...BROUGHT SOUTH ON A NORTHERLY BREEZE. ONE CHANGE IS THAT ALL OBSERVATION SITES ARE REPORTING VFR CONDITIONS WITH THESE CLOUDS. BELIEVE THIS IS A RESULT OF DRIER AIR ACCOMPANYING THE BREEZE WHICH IS EVIDENT BY FALLING DEWPOINTS. THEREFORE...THE TAF FORECAST STILL REFLECTS THE LOWER CLOUDS COMING THROUGH BUT BASES ARE NOW VFR. THE VFR CONDITIONS ARE LIKELY TO PERSIST THROUGH THE EVENING HOURS. TOWARDS 06Z WEDNESDAY NIGHT...THERE ARE INDICATIONS OF SOME SNOW THAT COULD MOVE INTO RST FROM THE WEST...BUT THE BULK OF THE PRECIPITATION LOOKS TO HOLD OFF UNTIL AFTER THE TAF PERIOD. REGARDING WINDS...SPEEDS WILL STAY SUSTAINED 10 TO 15 KT TODAY...STRONGEST THIS MORNING...DUE TO A RELATIVELY TIGHT PRESSURE GRADIENT IN PLACE. EXPECT THE WINDS TO DIMINISH THIS AFTERNOON AND EVENING AS HIGH PRESSURE BRIEFLY BUILDS IN. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...HALBACH LONG TERM...HALBACH AVIATION...AJ
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
612 PM CDT TUE MAR 11 2014 .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 309 PM CDT TUE MAR 11 2014 THE MAIN FOCUS THROUGH TOMORROW IS WITH HOW FAST THE BAND OF PRECIPITATION SHIFTS TO THE SOUTH TONIGHT FOLLOWED BY SNOW SHOWER CHANCES TOMORROW MORNING ALONG WITH HOW COLD IT WILL BE. SURFACE/LOW LEVEL TEMPERATURES PROVED TO BE A TAD TOO WARM TODAY TO CAUSE MUCH IF ANY SNOW TO DEVELOP ALONG THE BAND OF PRECIPITATION. 11.17Z RAP SOUNDINGS CONTINUE TO SHOW THAT THE LOW LEVELS SHOULD STAY WARM ENOUGH INTO THIS EVENING TO MAINLY YIELD RAIN WITH A BRIEF TRANSITION TO SNOW ON THE BACK/NORTH SIDE OF THE BAND. THE 17.12Z HRRR/RAP SHOW THIS BAND GETTING SOUTH OF DUBUQUE BY MID EVENING. AS A DEEPENING SURFACE LOW TRACKS TO THE SOUTHEAST OF THE REGION OVERNIGHT INTO TOMORROW MORNING...AN INVERTED SURFACE TROUGH WILL ROTATE FROM EAST TO WEST ACROSS THE REGION AS A SHORT WAVE MID LEVEL TROUGH DROPS DOWN FROM ONTARIO. WITH COLDER AIR MOVING IN WITH THIS TROUGH A SATURATED LAYER SHOULD DEVELOP IN THE ICE NUCLEATION ZONE BELOW -8C WITH JUST ENOUGH LIFT FROM THE SURFACE TROUGH TO PRODUCE SOME SNOW SHOWERS. 11.12Z WRF-ARW/NMM REFLECTIVITY GUIDANCE SHOWS A BAND OF SNOW SHOWERS DEVELOPING IN EASTERN WISCONSIN OVERNIGHT AND TRACKING TO THE SOUTHWEST THROUGH THE REGION TOMORROW MORNING. SUBSIDENCE THEN TAKES OVER AND SHOULD HELP TO CLEAR SKIES OUT A BIT GOING INTO THE AFTERNOON...BUT TEMPERATURES WILL STRUGGLE TO CLIMB MUCH WITH 850MB TEMPERATURES AROUND -15C. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 309 PM CDT TUE MAR 11 2014 THE NEXT CHANCE FOR SOME LIGHT SNOW COMES IN ON WEDNESDAY NIGHT/EARLY THURSDAY MORNING AS A RIDGE OF HIGH PRESSURE PUSHES TO THE EAST AND SOME LOW LEVEL WARM AIR ADVECTION SWINGS THROUGH THE REGION. THERE ARE SOME DIFFERING OPINIONS BETWEEN THE 11.12Z NAM/GFS/ECMWF/GEM WITH THIS BAND AND HOW STRONG THE WAA WILL BE. THE GFS IS THE FASTEST WITH HAVING THE SNOW COME IN ON WEDNESDAY EVENING WHILE THE NAM IS A TAD SLOWER AND STRONGER WITH THE WAA AND PRODUCES A LITTLE MORE QPF. THE ECMWF/GEM ARE BOTH MUCH WEAKER WITH THIS SYSTEM AND HARDLY SHOW ANY QPF AT ALL...SO THERE IS SOME UNCERTAINTY WITH WHETHER ANYTHING WILL OCCUR FROM THIS. COBB DATA FROM THE GFS/NAM WOULD SAY A HALF INCH OF ACCUMULATION OR LESS IF THE SNOW DOES OCCUR. TEMPERATURES WILL CLIMB BACK TOWARD NORMAL THURSDAY WITH SOUTHWESTERLY SURFACE WINDS. A WEAK COLD FRONT WILL COME THROUGH ON FRIDAY THOUGH TEMPERATURES SHOULD NOT DROP MUCH UNTIL THE WEEKEND COMES AND NORTHWESTERLY FLOW ALOFT SETS UP. REMOVED THE CHANCES FOR PRECIPITATION ON SUNDAY AS IT LOOKS LIKE THE SHORT WAVE TROUGH DIVING SOUTH OUT OF SOUTH CENTRAL CANADA WILL RUN TO THE WEST OF THE REGION. THE BETTER CHANCES APPEAR TO COME ON TUESDAY AS THE 11.12Z ECMWF BRINGS A SYSTEM OUT OF THE PLAINS AND TO THE SOUTH OF THE UPPER MISSISSIPPI RIVER VALLEY. THE 11.12Z GFS IS MUCH FURTHER TO THE NORTH WITH THIS SYSTEM AND WOULD BRING WARMER AIR INTO THE REGION. QUITE A BIT OF UNCERTAINTY OUT THERE...BUT ENOUGH TO WARRANT SOME CHANCES FOR PRECIPITATION ON TUESDAY. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING) ISSUED AT 612 PM CDT TUE MAR 11 2014 AN AREA OF MVFR CLOUDS OVER NORTHERN MINNESOTA ARE SUGGESTED BY MODELS TO DROP SOUTH ACROSS THE TAF SITES LATE TONIGHT INTO EARLY WEDNESDAY MORNING. THE CAUSE IS RELATED TO AN INCREASING NORTHERLY WIND TONIGHT WHICH SUSTAINED COULD PEAK AROUND 15 KT. GIVEN LACK OF SNOW OCCURRING OUT OF THESE CLOUDS AND SHALLOW EXTENT TO THEM...HAVE REMOVED ANY PRECIPITATION MENTION FROM THE TAFS. OTHERWISE...DRY AIR AHEAD OF AND BEHIND THESE CLOUDS WILL KEEP CONDITIONS VFR. LOOK FOR WINDS TO DIMINISH LATE WEDNESDAY AS HIGH PRESSURE BEGINS TO BUILD INTO THE TAF SITES. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...HALBACH LONG TERM...HALBACH AVIATION...AJ
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
1104 PM MDT TUE MAR 11 2014 .UPDATE... ISSUED AT 1055 PM MDT TUE MAR 11 2014 THE NEW COLDER AIR MASS CONTINUES TO BE REINFORCED FROM THE NE TONIGHT. SKIES HAVE CLEARED ACROSS THE FORECAST AREA EXCEPT IN THE NW SAN JUAN MTNS. THE 03Z RAP SHOWS ENHANCED VORTICITY IN THE DEFORMATION AXIS THAT IS STRETCHED ACROSS SOUTHERN UTAH AND SW COLORADO. LIGHT SNOW AND OBSCURED MTNS LIKELY TO CONTINUE UNTIL 3AM OR SO THEN CLEAR THERE TOO. THE WESTERN PORTION OF THE SHEARED TROUGH CLOSES JUST TO THE NW OF LAS VEGAS ON WEDNESDAY. A WEAK DEFORMATION ZONE REMAINS STRETCHED ACROSS THE CENTRAL FORECAST AREA THAT MAY PRODUCE SOME CLOUDS BUT NO SNOW. AFTER A COLD MORNING AFTERNOON TEMPERATURES WILL BE JUST A FEW DEGREES BELOW NORMAL. && .SHORT TERM...(TONIGHT THROUGH WEDNESDAY NIGHT) ISSUED AT 319 PM MDT TUE MAR 11 2014 SHEARING E-W ORIENTED TROF IS DROPPING ACROSS NORTHERN COLORADO AND UTAH THIS AFTERNOON. WATER VAPOR IS SHOWING TWO CIRCULATIONS BECOMING MORE DEFINED IN WATER VAPOR THIS AFTERNOON...ONE RETROGRADING TOWARD SALT LAKE CITY AND ANOTHER DROPPING ACROSS THE CHEYENNE RIDGE OF THE FRONT RANGE. DECENT COLD POOL ARCING SOUTHWARD BETWEEN THESE TWO FEATURES WITH THE DELTA T OR INSTABILITY AXIS LINING UP WELL WITH MOST ROBUST CONVECTION THIS AFTERNOON. DRY AIR IN THE LOW LAYERS AND THE CONVECTIVE NATURE IS HELPING SNOW MAKE IT TO THE GROUND WITH SURFACE TEMPERATURES WELL INTO THE 40S. LOOKING AT SNOW STAKES AND SNOTELS A GOOD 6 TO 10 INCHES LOOKS TO HAVE FALLEN ACROSS THE ADVISORY AREA WITH LOCALLY HIGHER AMOUNTS AIDED BY THE INSTABILITY. STILL EXPECT A RATHER QUICK DOWNTURN TO THE PRECIPITATION THIS EVENING WITH THE LOSS OF SURFACE HEATING. THE TWO CIRCULATIONS WILL CONTINUE TO DIVERGE WITH THE WESTERN CIRCULATION LIKELY FORMING A CLOSED LOW IN THE MID LEVELS BY WEDNESDAY AFTERNOON OVER SOUTHERN NEVADA. THIS WILL BECOME A REX LOW AS THE UPPER RIDGE BUILDS ACROSS THE NORTHERN ROCKIES AND KEEPS THINGS MORE QUIET FOR WEDNESDAY. MOSTLY SUNNY SKIES SHOULD BE IN PLACE WITH JUST A FEW HIGH BASED CLOUDS AND SHOWERS POPPING OVER THE HIGH PEAKS OF THE SAN JUANS WHERE THE INSTABILITY WILL BE THE HIGHEST. WITH CLEARING SKIES TONIGHT TEMPERATURES WILL BE QUITE A BIT COOLER THAN LAST NIGHT WITH LOWS DROPPING BACK INTO THE SINGLE DIGITS OVER THE HIGHER VALLEYS AND BASINS. TOMORROW/S HIGHS SHOULD BE A TAD WARMER BUT THEY STILL LOOK LIKE THEY/LL END UP ON THE COLD SIDE OF NORMAL. THE UPPER LOW WILL BEGIN TO GET A KICK EASTWARD WEDNESDAY NIGHT AS STRONGER ENERGY WORKS IT/S WAY THROUGH THE RIDGE. MOISTURE TRANSPORT VECTORS AROUND 300K SHOW THIS LOW PULLING IN THE PACIFIC MOISTURE TAP OFF THE BAJA COAST WHICH IT LOOKS TO USE FOR INCREASED PRECIPITATION CHANCES GOING INTO THURSDAY. .LONG TERM...(THURSDAY THROUGH TUESDAY) ISSUED AT 319 PM MDT TUE MAR 11 2014 THE UPPER LEVEL LOW AFOREMENTIONED BEGINS TO PROPAGATE EASTWARD ON THURSDAY WITH THE HELP OF AN UPPER LEVEL TROUGH COMING ONSHORE OVER THE PACIFIC NW AND MOVING EAST OVER THE NORTHERN ROCKIES. THOUGH THE CENTER OF ENERGY FROM THIS UPPER LEVEL LOW WILL MAINLY STAY TO THE SOUTH OF THE GRAND JUNCTION CWA...WE ARE EXPECTING A FEW AFTERNOON AND EARLY EVENING THUNDERSTORMS DUE TO INSTABILITY AND WRAP-AROUND MOISTURE ON THURSDAY IN THE FOUR CORNERS REGION. THE BEST FORCING ON THURSDAY IS FORECAST TO STAY JUST SOUTH OF THE FOUR CORNERS BUT CONVECTIVE SHOWERS AND THUNDERSTORMS ARE EXPECTED AS FAR NORTH AS THE UNCOMPAHGRE AND POTENTIALLY INTO THE CENTRAL MTNS. ONCE THIS DISTURBANCE PASSES...THE REGION REMAINS IN NORTHWEST FLOW WITH A JET MAX OVERHEAD WHICH MEANS THE RECENT PATTERN OF ACTIVE WEATHER EVERY FEW DAYS IS LIKELY TO CONTINUE THROUGH AT LEAST THE WEEKEND. BOTH THE GFS AND EC BRING THE NEXT WEATHER DISTURBANCE INTO WESTERN COLORADO ON SATURDAY WHICH HAS THE POTENTIAL TO CAUSE MAJOR IMPACTS ALONG COLORADO HIGHWAYS SATURDAY MORNING THROUGH SATURDAY NIGHT. AT THIS TIME...THIS DISTURBANCE IS FAIRLY PROGRESSIVE SO SHOULD SWING THROUGH WESTERN COLORADO QUICKLY AND NOT CAUSE PROBLEMS INTO SUNDAY MORNING. THIS TIMING COULD CHANGE BUT CONFIDENCE IS MODERATE AS MODELS THIS FAR OUT AGREE ON A SIMILAR SOLUTION. FROM SUNDAY ON IS WHEN MODEL CONFIDENCE DECREASES. THE LATEST 12Z EC HAS DRASTICALLY CHANGED FROM THE PREVIOUS 00Z RUN TO LINE UP MORE CLOSELY WITH THE 00Z AND 12Z GFS RUNS WHICH BUILD HIGH PRESSURE OVER THE GREAT BASIN. THE EC DOES KEEP NORTH CENTRAL COLORADO IN NORTHWEST FLOW AND SUGGESTS A DISTURBANCE COMES THROUGH MID WEEK BUT THIS DISTURBANCE LOOKS VERY WEAK AT THIS TIME. TEMPERATURES WILL REMAIN NEAR NORMAL OR SLIGHTLY ABOVE NORMAL THROUGHOUT NEXT WEEK. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY EVENING) ISSUED AT 1055 PM MDT TUE MAR 11 2014 VFR CONDITIONS WILL DOMINATE THROUGH WEDNESDAY NIGHT WITH ONE EXCEPTION. IN THE NW SAN JUAN MTNS UNTIL 10Z TONIGHT....FROM KTEX EAST TO SLUMGULLION PASS...MVFR TO LOCAL IFR CIGS IN -SHSN WITH MTN TOPS FREQUENTLY OBSCURED. && .GJT WATCHES/WARNINGS/ADVISORIES... CO...NONE. UT...NONE. && $$ UPDATE...JOE SHORT TERM...15 LONG TERM...JAM AVIATION...TGR
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
420 AM EDT WED MAR 12 2014 .SYNOPSIS... LOW PRESSURE IN THE MID MISSISSIPPI VALLEY WILL INTENSIFY RAPIDLY AS IT ARRIVES IN SOUTHERN OHIO THIS MORNING, THEN ACROSS NORTHERN NEW JERSEY LATER THIS EVENING. A VERY STRONG COLD FRONT WILL WHIP ACROSS OUR AREA WEDNESDAY EVENING, WITH THE STORM THEN RACING TO NOVA SCOTIA THURSDAY MORNING. LOW PRESSURE IN EASTERN CANADA FRIDAY AND SATURDAY WILL SEND ANOTHER COLD FRONT THROUGH THE MID ATLANTIC STATES EARLY SUNDAY. LOW PRESSURE THEN DEVELOPS ALONG THE SOUTHEAST COAST OF THE UNITED STATES NEXT MONDAY AND TUESDAY AND COULD PASS CLOSE TO OUR REGION. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... HIGH RESOLUTION MODELS SUCH AS THE HRRR SHOW THE PRIMARY AXIS OF PRECIPITATION ASSOCIATED WITH THE WAA GENERALLY NW OF OUR REGION THROUGH ABOUT 18Z. AFTER 18Z, COULD START TO SEE SHOWERS SPREADING FROM DELMARVA AND POCONOS ACROSS THE REST OF THE REGION. HOWEVER, GIVEN THE LIMITED INSTABILITY, IT STILL LOOKS LIKE THE MAIN SHOW WILL BE WITH THE COLD FRONT. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 AM THURSDAY/... COLD FRONT SHOULD SWEEP THROUGH THE REGION BETWEEN 22 AND 03Z. FORCING WITH THE COLD FRONT SHOULD BE ENOUGH TO OVERCOME THE STRONGLY SHEARED ENVIRONMENT FOR LINEAR CONVECTIVE SYSTEM. THINK THE SEVERE RISK WILL BE PRIMARILY OVER DELMARVA, FAR SE PA, AND S NJ WHERE THE CLOUDS WILL BE LAST TO ARRIVE, THUS WILL HAVE A BIT MORE HEATING TO ENHANCE THE INSTABILITY. THEN THE ATTENTION TURNS TO THE WINDS. THE STRONGEST WINDS ON LAND ARE EXPECTED IN THE POCONOS, WHERE TERRAIN EFFECTS WILL HELP MIXING, AND IN THE SOUTHERN HALF OF THE CWA WHERE THE ISALLOBARIC WIND COMPONENT IS EXPECTED TO BE THE STRONGEST. HAVE ISSUED A WIND ADVISORY FOR THESE LOCATIONS. THERE IS SOME RISK OF HIGH WIND WARNING FOR CAPE MAY AND COASTAL SUSSEX DUE TO THE FUNNELING EFFECTS THROUGH THE BAY, BUT WILL HOLD OFF ON THAT FOR NOW UNTIL WE SEE THE TREND OF UPSTREAM OBS BEHIND THE FRONT. && .LONG TERM /THURSDAY THROUGH TUESDAY/... AT THE START OF THE LONGTERM WE WILL BE DEALING WITH THE RAPID COOL-DOWN BEHIND THE INTENSE COLD FRONT AS IT MOVES WELL TO OUR EAST. WE WILL BE DRY BUT WITH LINGERING GUSTS AROUND 25 TO 30MPH AND TEMPERATURES NEARLY 20 DEGREES COLDER THAN NORMAL, WIND CHILL VALUES WILL REMAIN IN THE SINGLE DIGITS, POSSIBLY BELOW ZERO ACROSS THE NORTHERN ZONES, FOR MOST OF THE DAY. THE GOOD NEWS IS WE REALLY ONLY HAVE ONE DAY TO DEAL WITH THE ABRUPT COLD SHOT, THE BAD NEWS IS THAT THE WARMING TREND INTO THE WEEKEND LOOKS TO BE FLEETING, CREATING ANOTHER ROLLER COASTER EFFECT AS WE HEAD INTO THE NEW WORK WEEK. SOUTHWEST WINDS AHEAD OF THE NEXT COLD FRONT, PROGGED TO MOVE THROUGH LATER ON SATURDAY, WILL ALLOW TEMPERATURES TO CLIMB CLOSER TO NORMAL ON FRIDAY AND EVEN SLIGHTLY HIGHER ON SATURDAY. MUCH LIKE LAST WEEKEND, THE FRONTAL BOUNDARY ON SATURDAY IS NOT ALL THAT STRONG WITH LIMITED MOISTURE WITH MORE SPLIT FLOW EXPECTED. DO CARRY SLIGHT CHANCE POPS ACROSS THE NORTH WITH A FEW HUNDREDTHS OF PRECIPITATION POSSIBLE. THERMAL FIELDS WOULD ALLOW FOR SOME LIGHT SNOW SHOWERS ACROSS THE HIGHER TERRAIN AND A MIX CHANGING TO RAIN FURTHER SOUTH. SREF AND GEFS PROBS KEEP THE SOUTHERN HALF OF THE CWA DRY AT THIS TIME. SUNDAY WILL FEATURE AMPLE SUNSHINE AND A NEW COOLER AIRMASS. HIGH PRESSURE ACROSS THE UPPER MID-WEST SLIDES TO OUR NORTH HELPING TO REINFORCE COOLER TEMPERATURES. THIS WILL YIELD HIGHS SLIGHTLY BELOW AVERAGE. THE NEXT SYSTEM OF INTEREST BEGINS TO DEVELOP ALONG THE FRONTAL BOUNDARY THAT JUST DRAPED THROUGH THE REGION. THERE IS STILL A LOT OF UNCERTAINTY WITH THIS SYSTEM AS THE MID-LEVEL PATTERN DOESN`T PROVIDE A GOOD CONSENSUS AMONGST THE MID-RANGE GUIDANCE. LEANED HEAVILY ON THE WPC GUIDANCE AT THIS POINT BRINGING CHANCE POPS INTO THE REGION LATE SUNDAY NIGHT INTO MONDAY. THERMAL PROFILES AT THIS POINT WOULD INDICATE WIDESPREAD SNOW ACROSS THE NORTHERN HALF OF THE CWA WITH A BIT MORE MIXING ACROSS THE SOUTH. STILL PLENTY OF TIME TO FIGURE OUT HOW THIS SYSTEM WILL TRACK. && .AVIATION /08Z WEDNESDAY THROUGH SUNDAY/... THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY AND SURROUNDING AREAS. STARTING OFF WITH VFR CONDITIONS, BUT EXPECT MVFR CEILINGS TO MOVE IN FROM WEST TO EAST THROUGH THE DAY. ALSO MVFR VISIBILITIES WILL BE POSSIBLE WITH SHRA THROUGH THE DAY. THERE IS A RISK FOR ISOLATED TSRA THROUGH 21Z, BUT COVERAGE IS EXPECTED TO BE TOO LIMITED TO INCLUDE IN THE TAFS FOR NOW. TSRA IS MORE LIKELY WITH AND JUST BEHIND THE COLD FRONT THAT SHOULD BE SWEEPING THROUGH THE REGION BETWEEN 22 AND 03Z. THE COLD FRONT WILL ALSO BRING AN ABRUPT SHIFT FROM BREEZY S OR SE WINDS TO GUSTY NW WINDS. CONDITIONS SHOULD IMPROVE TO VFR WITHIN A FEW HOURS OF THE FRONT, BUT WINDS MAY NOT DIMINISH UNTIL NEAR SUNRISE. OUTLOOK... THURSDAY...VFR. GUSTY NORTHWEST WINDS AROUND 30 TO 35 KNOTS POSSIBLE. FRIDAY...VFR. WINDS VEER TOWARDS THE SOUTHWEST AND COULD BE GUSTY AT TIMES. SATURDAY...MOSTLY VFR. COLD FRONT WILL CROSS THE REGION ON SATURDAY WITH SUB-VFR POSSIBLE IN RAIN SHOWERS. SUNDAY...VFR. && .MARINE... WINDS AND SEAS WILL CONTINUE TO INCREASE THROUGH THE DAY. HOWEVER, THE STRONGEST WINDS ARE EXPECTED WITH AND BEHIND THE COLD FRONT WHICH SHOULD ARRIVE THIS EVENING. WINDS WILL STAY UP FOR MUCH OF THE NIGHT. GALES ARE EXPECTED ACROSS THE REGION, AND STORM FORCE WINDS POSSIBLE IN THE LOWER DE BAY AND ADJACENT OCEAN WATERS DUE TO THE FUNNELING EFFECTS. WINDS ARE NOT EXPECTED TO SUBSTANTIALLY SUBSIDE OVERNIGHT. OUTLOOK... THURSDAY...CONTINUATION OF GALES THROUGH THE EVENING HOURS DROPPING TO SCA THEREAFTER. FRIDAY...SCA LIKELY WITH WINDS VEERING TOWARDS THE SOUTHWEST. SATURDAY - SUNDAY...SUB-SCA CONDITIONS EXPECTED BY LATE SATURDAY MORNING. WINDS SHIFT BACK TOWARDS THE WEST-NORTHWEST BEHIND A COLD FRONT LATER ON SATURDAY. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...WIND ADVISORY FROM 6 PM THIS EVENING TO 11 AM EDT THURSDAY FOR PAZ054-055-060>062-070-071-101>104. NJ...WIND ADVISORY FROM 6 PM THIS EVENING TO 11 AM EDT THURSDAY FOR NJZ016>018-021>025. DE...WIND ADVISORY FROM 6 PM THIS EVENING TO 11 AM EDT THURSDAY FOR DEZ001>004. MD...WIND ADVISORY FROM 6 PM THIS EVENING TO 11 AM EDT THURSDAY FOR MDZ008-012-015-019-020. MARINE...GALE WARNING FROM 7 PM THIS EVENING TO 1 AM EDT FRIDAY FOR ANZ450>452. STORM WARNING FROM 11 PM THIS EVENING TO 11 AM EDT THURSDAY FOR ANZ431-453>455. GALE WARNING FROM 7 PM THIS EVENING TO 8 PM EDT THURSDAY FOR ANZ430. && $$ SYNOPSIS...DRAG/GORSE NEAR TERM...JOHNSON SHORT TERM...JOHNSON LONG TERM...HEAVENER AVIATION...HEAVENER/JOHNSON MARINE...HEAVENER/JOHNSON
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
201 AM EDT WED MAR 12 2014 .SYNOPSIS... AN UPPER DISTURBANCE AND PRE-FRONTAL TROUGH OF LOW PRESSURE WILL MOVE EAST TOWARD THE SOUTHERN ATLANTIC COAST OVERNIGHT BRINGING SHOWERS TO MUCH OF SOUTHEAST GEORGIA AND SOUTHERN SOUTH CAROLINA. A STRONG COLD FRONT WILL THEN MOVE WEDNESDAY NIGHT...FOLLOWED BY MUCH COOLER HIGH PRESSURE THROUGH FRIDAY. ANOTHER COLD FRONT WILL MOVE THROUGH OVER THE WEEKEND AND WILL STALL NOT FAR OFFSHORE. A WAVE OF LOW PRESSURE WILL RIDE ALONG THE FRONT EARLY NEXT WEEK...AS A HIGH PRESSURE WEDGE DEVELOPS INLAND. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... THROUGH SUNRISE...WIDESPREAD RAINFALL WILL CONTINUE TO FILL IN ACROSS THE FORECAST AREA FROM THE SOUTHWEST. THIS AREA OF PRECIPITATION IS BEING DRIVEN BY A NOTABLE SOUTHERN STREAM SHORTWAVE THAT IS BEGINNING TO DAMPEN OUT AS IT PUSHES FURTHER EASTWARD. POPS HAVE BEEN INCREASED SUCH THAT ALL LOCATIONS GET CATEGORICAL POPS THROUGH SUNRISE. THIS FEATURE IS MOVING FAIRLY QUICKLY AND THE RAP APPEARS TO HAVE THE BEST BEAT ON ITS TIMING MOVING FORWARD. THIS WILL BE A RELATIVELY QUICK SHOT OF RAINFALL AND WILL BE EXITING THE FORECAST AREA NOT TOO LONG AFTER SUNRISE. TEMPERATURES WILL NOT LIKELY FALL VERY MUCH THROUGH THE REST OF THE NIGHT...WITH LOWS ONLY BOTTOMING OUT IN THE LOW 60S TO AROUND 60. && .SHORT TERM /6 AM THIS MORNING THROUGH FRIDAY/... A POTENT UPPER SHORTWAVE WILL SHIFT ACROSS THE OHIO VALLEY AND INTO THE NORTHEAST UNITED STATES WEDNESDAY AND WEDNESDAY NIGHT. A SOUTHERN STREAM VORTICITY CENTER WILL MOVE ACROSS THE SOUTHEAST STATES WEDNESDAY MORNING AND OFF THE COAST BY EARLY AFTERNOON. ANY LINGERING PRECIPITATION WILL SHIFT OFFSHORE WITH THE SHORTWAVE... AFTER WHICH THE LOW AND MID LEVEL FLOW VEERS TO WESTERLY. MEANWHILE A STRONG COLD FRONT ASSOCIATED WITH THE NORTHERN SHORTWAVE WILL PUSH INTO OUR AREA WEDNESDAY EVENING. AHEAD OF THE FRONT BUT BEHIND THE SHORTWAVE WE EXPECT PARTIAL CLEARING DURING THE AFTERNOON ALONG WITH STRONG PRE-FRONTAL COMPRESSION. NUMERICAL GUIDANCE HAS INCREASED A FEW DEGREES FOR AFTERNOON HIGH TEMPS...ESPECIALLY ACROSS SOUTHEAST GA WHERE SKIES MAY CLEAR A BIT EARLIER. WE NUDGED HIGH TEMPS UP TO SHOW 80-83F ACROSS THE SOUTHEASTERN HALF OF THE AREA WITH UPPER 70S FARTHER INLAND. A SUBSTANTIAL LOW-LEVEL JET WILL DEVELOP LATE WEDNESDAY MORNING AS THE UPPER TROUGH AXIS APPROACHES. 850 MB WINDS INCREASE TO 40-50 KT BETWEEN 18-00Z DEPENDING ON WHICH MODEL YOU ANALYZE. WITH STRONG WARMING THE MIXED LAYER MAY EXPAND AS HIGH AS 825 MB WHICH WILL TAP INTO THESE STRONG WINDS ALOFT. THUS A WINDY DAY IS IN STORE FOR MUCH OF THE AREA. AT THIS POINT WE ARE SHOWING BOTH SUSTAINED WINDS AND GUSTS REMAINING BELOW WIND ADVISORY CRITERIA BUT LATER SHIFTS MAY NEED TO CONSIDER AN ADVISORY IN SOME AREAS IF WIND PROGS INCREASE FURTHER. CLEARING SKIES AND COLD ADVECTION EXPECTED WEDNESDAY NIGHT WITH LOW TEMPS DROPPING INTO THE MIDDLE TO UPPER 30S. A FAIRLY STRONG GRADIENT THROUGH THE NIGHT WILL PRECLUDE FROST ISSUES BUT MAKE FOR CHILLY CONDITIONS BY DAYBREAK THURSDAY. THE LOW-LEVEL RIDGE AXIS WILL SHIFT TOWARD THE AREA ON THURSDAY WHILE COLD ADVECTION PERSISTS. DOWNSLOPE WARMING WILL PUSH TEMPS UPWARD A TAD BUT HIGH TEMPS WILL ONLY REACH THE UPPER 50S DESPITE FULL SUNSHINE. DEEP LAYERED RIDGING THURSDAY NIGHT WILL ALLOW FOR CLEAR SKIES AND A DECOUPLING BOUNDARY LAYER...YIELDING OPTIMAL RADIATIONAL COOLING CONDITIONS. A COLD NIGHT IS THUS IN STORE...WITH A FREEZE OCCURRING MANY AREAS AWAY FROM THE COAST. WE ARE STILL SHOWING UPPER 20S TO LOWER 30S FOR LOW TEMPS WHICH WILL EVENTUALLY REQUIRE A FREEZE WATCH. FRIDAY BEGINS A WARM UP AS THE RIDGE AXIS SHIFTS EAST OF THE AREA AND WARM ADVECTION COMMENCES. HIGH TEMPS WILL PUSH INTO THE 60S WITH DRY CONDITIONS. LAKE WINDS...GUSTY WINDS WILL DEVELOP ON LAKE MOULTRIE LATE WEDNESDAY MORNING AHEAD OF A STRONG COLD FRONT AND WITH A STRENGTHENING LOW-LEVEL JET. WE ISSUED A LAKE WIND ADVISORY STARTING AT 10 AM WEDNESDAY. GUSTY WINDS WILL PERSIST THROUGH THURSDAY MORNING BEFORE QUICKLY IMPROVING. && .LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/... THE ATLANTIC HIGH LATE IN THE WEEK GIVES WAY TO OUR NEXT COLD FRONT. THAT FRONT LIMPS THROUGH THE AREA OVER THE WEEKEND AS IT BECOMES PARALLEL TO THE THE QUASI-ZONAL FLOW UPSTAIRS. ALTHOUGH THERE IS A DECENT RETURN OF MOISTURE...FORCING REMAINS IN DOUBT SO WE DON/T SEE TOO MUCH IN THE WAY OF SHOWERS JUST YET. THE FRONT FINALLY SHIFTS THROUGH AND STALLS OUT OVER THE NEARBY ATLANTIC EARLY NEXT WEEK...AWAITING FOR THE POTENTIAL FORMATION OF A SURFACE WAVE TO RIDE NE ALONG THE FRONT AS A HIGH PRESSURE WEDGE DEVELOPS INLAND. SINCE THERE IS MUCH CONCERN ON EXACTLY HOW THIS EVOLVES WE COULD GO ANYWHERE FROM SOME SIGNIFICANT RAINFALL TO A DRY FORECAST...WE HAVE PLAYED A CLIMATOLOGICAL FORECAST OF NO MORE THAN CHANCE POPS. TEMPS WILL NOT STRAY FAR FROM MID MARCH AVERAGES THROUGH THE WEEKEND...THEN SHOULD DROP BELOW NORMALS MONDAY AND TUESDAY PROVIDED THE SCENARIO WE JUST MENTIONED PANS OUT. && .AVIATION /06Z WEDNESDAY THROUGH SUNDAY/... WIDESPREAD PRECIPITATION CONTINUES TO FILL IN ACROSS THE FORECAST AREA FROM THE SOUTHWEST AND WILL FIRST IMPACT KSAV FOLLOWED BY KCHS. LOOKING AT UPSTREAM OBSERVATIONS...MOST SITES ARE NOT SEEING VISIBILITIES REDUCED BELOW VFR LEVELS WITH THE RAINFALL...THOUGH THERE ARE SOME CEILING RESTRICTIONS NOTED. IN FACT...GUIDANCE FEATURES MVFR CEILINGS BEGINNING AROUND 08-09Z AT KSAV AND THAT IS WHAT I HAVE TIMED INTO THE FORECAST. SIMILAR CONDITIONS ARE EXPECTED AT KCHS...THOUGH AN HOUR OR TWO LATER. THERE IS STILL A LOW END POTENTIAL FOR SHORT LIVED IFR CEILINGS...BUT THERE ISN/T MUCH NOTED IN UPSTREAM OBSERVATIONS SO I HAVE KEPT THE FORECAST MVFR AT WORST. PRECIPITATION WILL LARGELY WRAP UP IN THE MID/LATE MORNING HOURS AND THE REST OF THE DAY IS EXPECTED TO BE DRY. LINGERING MVFR CEILINGS WILL SCATTER OUT AND VFR CONDITIONS ARE IN PLACE THE REST OF THE PERIOD. WINDS WILL INCREASE STARTING IN THE MID MORNING AND WILL PEAK WITH WIND GUSTS APPROACHING 30 KTS IN THE AFTERNOON FROM THE SOUTHWEST. WINDS WILL REMAIN ELEVATED AND GUSTY THROUGH THE EARLY THURSDAY MORNING HOURS AS THE FRONT PUSHES THROUGH AND WINDS VEER AROUND TO WESTERLY. EXTENDED AVIATION OUTLOOK...VFR LATE THURSDAY MORNING THROUGH SATURDAY. MVFR CEILINGS AND/OR VSBYS POSSIBLE SATURDAY NIGHT AND SUNDAY WITH A COLD FRONT. GUSTY WINDS EXPECTED WEDNESDAY AFTERNOON THROUGH THURSDAY MORNING...THEN AGAIN SATURDAY AFTERNOON. && .MARINE... OVERNIGHT...LOW PRESSURE WILL STRENGTHEN WELL NORTHWEST OF THE REGION AND THE SURFACE PRESSURE GRADIENT/LOW LEVEL WINDS WILL INTENSIFY ACCORDINGLY...SUPPORTING INCREASING SOUTHWEST WINDS. AFTER MIDNIGHT...THE POTENTIAL FOR GUSTS TO 25 KT WILL INCREASE BEYOND 20 NM. ELSEWHERE...WINDS WILL STEADILY INCREASE. EVENING SEAS 1-2 FT WITHIN NEARSHORE WATERS AND 2-3 FT BEYOND 20 NM WILL WILL BUILD IN RESPONSE TO THE INCREASING WINDS...BECOMING 3-4 FT WITHIN 20 NM AND 4-5 FT BEYOND. CANNOT RULE OUT PATCHY SEA FOG WITHIN NEARSHORE WATERS/OUTSIDE CHARLESTON HARBOR TOWARD DAYBREAK AS LOW-LEVEL MOISTURE INCREASES. HOWEVER...THE CHANCE FOR SIGNIFICANT SEA FOG IS TOO LOW AT THIS TIME TO MENTION. WEDNESDAY WE EXPECT INCREASING SOUTHWESTERLY FLOW AHEAD OF A COLD FRONT BEFORE WINDS SHIFT TO WNW BEHIND THE FRONT WEDNESDAY NIGHT. A WARM ADVECTION REGIME ON WEDNESDAY ACROSS COLD ATLANTIC WATERS WILL NOT SUPPORT GALE CONDITIONS THOUGH WE DO ANTICIPATE SOLID SMALL CRAFT ADVISORIES ALL WATERS. BY WEDNESDAY NIGHT THE COLD ADVECTION BEHIND THE COLD FRONT AND GEOSTROPHIC WINDS INCREASING TO 40-50 KT WILL SUPPORT POSSIBLE GALES FOR THE SC NEARSHORE AND GA OFFSHORE WATERS SO WE ISSUED A GALE WATCH FOR THOSE WATERS. ELSEWHERE SOLID SMALL CRAFT CONDITIONS WILL CONTINUE. CONDITIONS IMPROVE DRASTICALLY THURSDAY MORNING AS THE UPPER SHORTWAVE SHIFTS EAST AND THE COLD ADVECTION DIMINISHES. THURSDAY NIGHT THROUGH SUNDAY...WE ANTICIPATE THE APPROACH OF A WEAK COLD FRONT LATER SATURDAY THAT STRUGGLES TO MOVE INTO AND THROUGH THE WATERS SUNDAY...STALLING OVER OR NEAR THE WATERS THROUGH MONDAY. A HIGH PRESSURE WEDGE WILL FORM INLAND BEHIND THE FRONT...AND PRESSURE PINCHING WILL TAKE PLACE FOR EARLY NEXT WEEK. SMALL CRAFT ADVISORIES ARE YET AGAIN POSSIBLE DURING THAT TIME. && .CHS WATCHES/WARNINGS/ADVISORIES... GA...NONE. SC...LAKE WIND ADVISORY FROM 10 AM THIS MORNING TO NOON EDT THURSDAY FOR SCZ045. MARINE...GALE WATCH FROM THIS EVENING THROUGH THURSDAY MORNING FOR AMZ350-352-374. SMALL CRAFT ADVISORY FROM 11 AM THIS MORNING TO 6 PM EDT THIS EVENING FOR AMZ352. SMALL CRAFT ADVISORY FROM 8 AM THIS MORNING TO 6 PM EDT THIS EVENING FOR AMZ350. SMALL CRAFT ADVISORY FROM NOON TODAY TO NOON EDT THURSDAY FOR AMZ354. SMALL CRAFT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR AMZ374. SMALL CRAFT ADVISORY FROM 11 AM THIS MORNING TO 2 PM EDT THURSDAY FOR AMZ330. && $$ SYNOPSIS... NEAR TERM...BSH SHORT TERM...JRL LONG TERM... AVIATION...BSH MARINE...JRL/SPR
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
427 AM CDT WED MAR 12 2014 .MESOSCALE DISCUSSION... 350 AM CDT HAVE MADE SOME ADJUSTMENTS TO HEADLINES...NAMELY TO BRING UP EXPIRATION TIMES...INCLUDING WARNING FOR THE CHICAGO AREA. ALSO DID DOWNGRADE THE WARNING IN A HANDFUL OF COUNTIES THAT EITHER 1. RECEIVED CONSIDERABLY LESS SNOWFALL THAN ORIGINALLY FORECAST OR 2. WILL HAVE AN EARLIER END TIME WITH LESS BLOWING SNOW THAN INITIALLY THOUGHT AND THUS IMPACTS AFTER SUNRISE WILL BE CONSIDERABLY LESS...SO DID NOT FEEL WARNING WAS ANY LONGER APPROPRIATE FOR THOSE AREAS. THE VERY WELL-DEFINED UPPER LOW IS ENTERING WESTERN IL AS OF 330 AM WITH FURTHER AMPLIFICATION OCCURRING AS NORTHERN STREAM SHORT WAVE FROM MN DIGS SOUTHEAST TOWARD/INTO THIS SYSTEM. THE DEFORMATION AREA SEEMS TO BE FOLLOWING SUIT...WITH INCREASED REFLECTIVITY SINCE 300 AM IN A SOUTHWEST TO NORTHEAST CORRIDOR ALIGNING WITH FRONTOGENESIS...INCLUDING OVER CHICAGO. HAVE HAD A COUPLE LIGHTNING STRIKES NEAR PONTIAC IN THE PAST COUPLE HOURS AND JUST PRIOR TO THAT SEVERAL REPORTS THROUGH SOCIAL MEDIA OF HEARING THUNDER. SO SOME EMBEDDED HEAVIER RATES ARE LIKELY WITHIN THIS AXIS GIVEN REFLECTIVITY AND JUST WHAT IS OCCURRING OUT THE WINDOW IN ROMEOVILLE...INCLUDING WITH LARGE FLAKES COMMON OF HIGH MIXING RATIO SCENARIOS. CONTINUE THE WARNING FOR THE CHICAGO METRO AREA AND FAR NORTHWEST INDIANA BUT MOVE UP THE EXPIRATION TIME TO 11 AM...AND IT COULD END UP BEING CANCELLED EVEN EARLIER IF BLOWING SNOW AND ATTENDANT IMPACTS ARE DETERMINED TO BE LESS. FURTHER TO THE SOUTHEAST...MAINLY SOUTH OF A PONTIAC TO RENSSELAER LINE...GREATER ELEVATED INSTABILITY IS PRESENT PER LOOK OF RADAR ECHOES AND RAP ANALYSIS. MUCH OF THIS AREA HOWEVER CHANGED OVER TO ALL SNOW ONLY AT 2-330 AM AND THUS ACCUMULATIONS LOOK LIMITED...WHICH WE KNEW WOULD COULD OCCUR. SOME OF THE HEAVIEST CONVECTION JUST MISSED OVERRIDING THIS AREA HAS NOW SKIRTED INTO NORTHERN INDIANA. SO FOR THAT REASON AND REPORTS RECEIVED THROUGH DISPATCH...HAVE DOWNGRADED THOSE SOUTHERN AREAS...AS BLOWING SNOW SHOULD BE QUITE LIMITED THIS MORNING. REST OF TODAY... THE PRIMARY CHANGES IN THE FORECAST WERE A QUICKER DIMINISHING OF ANY LIGHT SNOW CHANCES AS WELL AS TO BUMP UP TEMPERATURES NAMELY THIS MORNING. DEEP DRY AIR AND SUPPRESSION LOOK TO MOVE QUICKLY INTO THE AREA BY LATE MORNING BEHIND THIS SYSTEM. CONTINUING LOW- LEVEL CYCLOGENESIS OFF TO THE EAST WILL DRIVE COLD AIR ADVECTION INTO THE REGION...AND PROFILES WILL BE SUPPORTIVE OF KEEPING STRATOCU AND MAYBE SOME FLURRIES INTO EARLY TO MID AFTERNOON. TEMPERATURES ARE FAIRLY HOMOGENEOUS UP TO CENTRAL/SOUTHERN WI EARLY THIS MORNING...SO LOW-LEVEL THERMAL ADVECTION LOOKS TO BE NEUTRAL THROUGH DAYBREAK AND THEN SLIGHT COLD AIR ADVECTION THIS MORNING. TEMPERATURES SHOULD LEVEL OUT THIS AFTERNOON AS AT LEAST SOME MARCH SUNSHINE OFFSETS ANY COLD AIR ADVECTION. WITH NOT AS COLD OF AIR QUICKLY COMING INTO THE AREA...THE POSSIBILITY OF LAKE EFFECT SNOW SHOWERS INTO NORTHWEST INDIANA LOOKS QUITE SMALL...BUT POSSIBLY SOME CLOUDS GENERATING INTO LAKE AND PORTER COUNTIES THIS AFTERNOON. TONIGHT... HIGH PRESSURE WILL MOVE OVER THE REGION TONIGHT AND SET THE STAGE FOR A COLD NIGHT BY MID-MARCH STANDARDS. HIGH CLOUDS DO LOOK TO SPILL INTO THE WESTERN FORECAST AREA AS THE NIGHT PROGRESSES AS A SHEARED WEAK SHORTWAVE DROPS SOUTHWARD ON THE BACKSIDE OF THE DEVELOPING LONGWAVE TROUGH. BUT IT LOOKS TO BE A LITTLE TOO LATE TO STOP TEMPERATURES FROM DROPPING NICELY OVER FRESH SNOW COVER THIS EVE INTO EARLY OVERNIGHT. FORECAST TEMPERATURES WITH MODEST CONFIDENCE ARE SINGLE DIGITS IN OUTLYING AREAS TO 10 TO 15 IN THE CHICAGO METRO. THAT LINES UP WITH THE 850MB TEMPERATURES OF -12C TO -15C ACROSS THE FORECAST AREA BY TONIGHT...WHICH ARE WELL BELOW CLIMO. IF CLOUDS WERE TO MOVE IN QUICKER IT WOULD RESULT IN MINS POTENTIALLY QUITE A BIT WARMER. THURSDAY AND BEYOND... WHILE THE UPPER FLOW PATTERN BECOMES NORTHWEST AND REMAINS DECENTLY ACTIVE THROUGH THE REST OF THE FORECAST PERIOD...WE REMAIN ON THE ANTICYCLONIC SIDE. THUS WE LOOK TO FREQUENTLY MISS THE BEST FORCING AND DEEPER SATURATION OF EACH QUICK-MOVING SYSTEM. IT DOES MAKE FOR A CHALLENGE WITH TEMPERATURES...ESPECIALLY WEIGHING RECENT SNOW COVER AND OCCASIONALLY PASSING CLOUD COVER. DO MAINTAIN A SMALL CHANCE FOR LIGHT SNOW THURSDAY MORNING IN NORTHERN AREAS AS WARM AIR ADVECTION ALOFT MOVES IN BEHIND THE TROUGH. SATURATION LOOKS TO BE A PROBLEM...BUT THE ISENTROPIC ASCENT IS PRETTY STRONG AND SATURATION ON BOTH THE NAM AND GFS IS DEPICTED TO BE LOW ENOUGH FOR SOME LIGHT SNOW TO REACH THE GROUND...IF IT CAN MATERIALIZE. FRIDAY LOOKS MILD WITH TEMPERATURES POTENTIALLY PUSHING 50 DEGREES AS WEST SOUTHWEST LOW-LEVEL FLOW BRING A WARM SECTOR OF ONE OF THE QUICK-MOVING SYSTEMS INTO OUR AREA. HAVE GONE WITH AN GFS/EC BLEND FOR THE WEEKEND INTO EARLY NEXT WEEK. THE GFS IS CONSIDERABLY COLDER FOR SUNDAY AND SUNDAY NIGHT WITH A STRONG CANADIAN HIGH PASSING OVER THE AREA...WHILE THE EC FAVORS THIS FEATURE TO BE MUCH FURTHER NORTH AND WEAKER. MTF && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 06Z... * HEAVY SNOW THROUGH 10Z-11Z WITH VLIFR CIGS/VIS. * STRONG/GUSTY NORTHERLY WINDS THROUGH MID/LATE AFTERNOON. * MVFR CIGS AFTER SNOW ENDS THROUGH MID AFTERNOON. CMS //DISCUSSION...UPDATED 06Z... PRECIPITATION HAS TRANSITIONED TO A WET SNOW ACROSS THE CHICAGO TERMINALS WITH A MIX OF RAIN STILL POSSIBLE ALONG A GYY/JOT LINE. LARGE AREA OF SNOW OVER SOUTHEAST IA/NORTHERN MO AND WESTERN IL WILL CONTINUE EAST/NORTHEAST ACROSS THE TERMINALS THROUGH THE EARLY MORNING HOURS WITH PREVAILING MODERATE SNOW EXPECTED. PERIODS/BURSTS OF HEAVY SNOW ALSO POSSIBLE AND MAINTAINED PREVIOUS TEMPO. WITH A SHARP EDGE EXPECTED ALONG THE NORTHERN EDGE OF THE SNOW...PREVAILING VISIBILITIES AT ORD/DPA COULD BE A BIT HIGHER THAN ADVERTISED AND WILL NEED TO MONITOR TRENDS OVER THE NEXT FEW HOURS. STILL A FEW LIGHTNING STRIKES...AT TIMES...WHICH WILL BE POSSIBLE IN THE BURSTS OF HEAVIER SNOW BUT EXPECTED COVERAGE TOO LOW FOR MENTION IN THE FORECAST. SHORT TERM/HI RES GUIDANCE IN GOOD AGREEMENT WITH THE HEAVIEST SNOW SHIFTING EAST OF THE CHICAGO TERMINALS 10Z-11Z WITH RAPID IMPROVEMENT IN BOTH CIGS AND VIS EXPECTED IN THE 11Z-13Z TIME PERIOD. FURTHER NORTHWEST AT RFD...PERIOD OF LIGHT SNOW STILL POSSIBLE FOR A FEW HOURS...BUT HEAVIER SNOW AND LOWER CONDITIONS APPEAR TO REMAIN SOUTH OF RFD. NORTH/NORTHEAST WINDS HAVE BEEN GUSTING INTO THE 20-25KT RANGE AT TIMES BUT ONE MINUTE DATA AT ORD/MDW HAVE BEEN RELATIVELY GUST FREE SINCE PRECIP HAS CHANGED OVER TO SNOW. WINDS WILL INCREASE OVERNIGHT...BUT NOT QUITE AS FAST OR STRONG AS PREVIOUSLY EXPECTED. STRONGEST WINDS LIKELY TO OCCUR AFTER SNOW ENDS AND CONTINUE FOR MUCH OF THE DAY WITH NORTHERLY DIRECTIONS. SNOW IS FAIRLY WET WITH TEMPS STILL IN THE LOWER 30S AND WITH EXPECTED LOWER SPEEDS/GUSTS DURING MUCH OF THE FALLING SNOW...HAVE REMOVED BLOWING SNOW...WHICH MAY STILL BE POSSIBLE WITH ANY LIGHTER/DRIER SNOW THAT FALLS AS SNOWFALL IS ENDING TOWARD DAYBREAK. CMS //ORD AND MDW CONFIDENCE...UPDATED 06Z... * HIGH FOR SNOW/CIG/VIS TRENDS. * MEDIUM FOR WIND SPEEDS/GUSTS/DIRECTIONS AND TIMING. * MEDIUM FOR MVFR CIGS INTO THIS AFTERNOON. CMS //OUTLOOK FOR ORD/MDW FOR 12Z THURSDAY-12Z TUESDAY...UPDATED 00Z... * THURSDAY...DRY/VFR. GUSTY SOUTHWEST WINDS. * FRIDAY...DRY/VFR. GUSTY WESTERLY WINDS. * SATURDAY...DRY/VFR. * SUNDAY...SLIGHT CHANCE OF SNOW. * MONDAY...DRY/VFR. KJB && .MARINE... 210 PM CDT LOW PRESSURE OVER THE CENTRAL PLAINS WILL CONTINUE TO DEEPEN AS IT TRACKS EAST ACROSS SOUTHERN ILLINOIS TONIGHT AND INTO THE OHIO VALLEY WEDNESDAY. AS THE LOW TRACKS SOUTH AND THEN SOUTHEAST OF THE LAKE...HIGH PRESSURE WILL ALSO BUILD ACROSS THE UPPER GREAT LAKES REGION...SETTING UP STRONG NORTH WINDS. THE COMBINATION OF A STRONG GRADIENT AND STRONG COLD ADVECTION WILL LEAD TO WINDS QUICKLY INCREASING TO GALES BY LATE THIS EVENING. THE LATEST GUIDANCE HAS BEEN RELATIVELY CONSISTENT IN INDICATING THE POTENTIAL FOR HIGH END GALES BY LATE WEDNESDAY MORNING AND EARLY AFTERNOON...WITH THE STRONGEST GALES OVER THE SOUTHERN PORTIONS OF THE LAKE...INCLUDING THE NEARSHORE WATERS. BY WEDNESDAY EVENING...THE HIGH PRESSURE WILL BEGIN TO SPREAD ACROSS LAKE MICHIGAN ALLOWING WINDS TO SUBSIDE BELOW GALE FORCE. BY THURSDAY NIGHT...THE HIGH WILL PUSH TO THE SOUTHEAST OF THE LAKE AS A CLIPPER DROPS OUT OF NORTHERN ALBERTA AND SWINGS JUST NORTH OF THE UPPER GREAT LAKES ON FRIDAY. WITH THE SFC HIGH SAGGING OFF THE SERN COAST...A PERIOD OF SWLY WINDS WILL DEVELOP AHEAD OF AN APPROACHING COLD FRONT TRAILING FROM THE CLIPPER. ANTICIPATE A PERIOD OF BRISK SLY TO SWLY WINDS FOR THURSDAY NIGHT THROUGH FRIDAY...BUT MORE GALES ARE NOT EXPECTED AT THIS TIME. AS THE CLIPPER TURNS NEWD INTO QUEBEC...IT WILL DRAG A WEAK COLD FRONT DOWN THE LAKE WITH ANOTHER ARCTIC HIGH BUILDING IN BEHIND THE FRONT. 25-30KT NORTH WINDS WILL SET UP FOLLOWING THE FROPA FOR SATURDAY NIGHT AND SUNDAY...BUT AS THE HIGH SPREADS ACROSS THE GREAT LAKES SUNDAY NIGHT...WINDS SHOULD BECOME MORE LIGHT AND VARIABLE. KREIN && .LOT WATCHES/WARNINGS/ADVISORIES... IL...WINTER STORM WARNING...ILZ013-ILZ014-ILZ020-ILZ021-ILZ022-ILZ023 UNTIL 11 AM WEDNESDAY. WINTER WEATHER ADVISORY...ILZ006-ILZ011-ILZ012 UNTIL 7 AM WEDNESDAY. WINTER WEATHER ADVISORY...ILZ019-ILZ032-ILZ033-ILZ039 UNTIL 11 AM WEDNESDAY. IN...WINTER STORM WARNING...INZ001-INZ002 UNTIL 11 AM WEDNESDAY. WINTER WEATHER ADVISORY...INZ010-INZ011-INZ019 UNTIL 11 AM WEDNESDAY. LM...GALE WARNING...LMZ080-LMZ669-LMZ671-LMZ673-LMZ675-LMZ740-LMZ741- LMZ742-LMZ743-LMZ744-LMZ745-LMZ777-LMZ779-LMZ870-LMZ872- LMZ874-LMZ876-LMZ878 UNTIL 10 PM WEDNESDAY. GALE WARNING...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-LMZ567- LMZ868 UNTIL 7 PM WEDNESDAY. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
410 AM CDT WED MAR 12 2014 .MESOSCALE DISCUSSION... 350 AM CDT HAVE MADE SOME ADJUSTMENTS TO HEADLINES...NAMELY TO BRING UP EXPIRATION TIMES...INCLUDING WARNING FOR THE CHICAGO AREA. ALSO DID DOWNGRADE THE WARNING IN A HANDFUL OF COUNTIES THAT EITHER 1. RECEIVED CONSIDERABLY LESS SNOWFALL THAN ORIGINALLY FORECAST OR 2. WILL HAVE AN EARLIER END TIME WITH LESS BLOWING SNOW THAN INITIALLY THOUGHT AND THUS IMPACTS AFTER SUNRISE WILL BE CONSIDERABLY LESS...SO DID NOT FEEL WARNING WAS ANY LONGER APPROPRIATE FOR THOSE AREAS. THE VERY WELL-DEFINED UPPER LOW IS ENTERING WESTERN IL AS OF 330 AM WITH FURTHER AMPLIFICATION OCCURRING AS NORTHERN STREAM SHORT WAVE FROM MN DIGS SOUTHEAST TOWARD/INTO THIS SYSTEM. THE DEFORMATION AREA SEEMS TO BE FOLLOWING SUIT...WITH INCREASED REFLECTIVITY SINCE 300 AM IN A SOUTHWEST TO NORTHEAST CORRIDOR ALIGNING WITH FRONTOGENESIS...INCLUDING OVER CHICAGO. HAVE HAD A COUPLE LIGHTNING STRIKES NEAR PONTIAC IN THE PAST COUPLE HOURS AND JUST PRIOR TO THAT SEVERAL REPORTS THROUGH SOCIAL MEDIA OF HEARING THUNDER. SO SOME EMBEDDED HEAVIER RATES ARE LIKELY WITHIN THIS AXIS GIVEN REFLECTIVITY AND JUST WHAT IS OCCURRING OUT THE WINDOW IN ROMEOVILLE...INCLUDING WITH LARGE FLAKES COMMON OF HIGH MIXING RATIO SCENARIOS. CONTINUE THE WARNING FOR THE CHICAGO METRO AREA AND FAR NORTHWEST INDIANA BUT MOVE UP THE EXPIRATION TIME TO 11 AM...AND IT COULD END UP BEING CANCELLED EVEN EARLIER IF BLOWING SNOW AND ATTENDANT IMPACTS ARE DETERMINED TO BE LESS. FURTHER TO THE SOUTHEAST...MAINLY SOUTH OF A PONTIAC TO RENSSELAER LINE...GREATER ELEVATED INSTABILITY IS PRESENT PER LOOK OF RADAR ECHOES AND RAP ANALYSIS. MUCH OF THIS AREA HOWEVER CHANGED OVER TO ALL SNOW ONLY AT 2-330 AM AND THUS ACCUMULATIONS LOOK LIMITED...WHICH WE KNEW WOULD COULD OCCUR. SOME OF THE HEAVIEST CONVECTION JUST MISSED OVERRIDING THIS AREA HAS NOW SKIRTED INTO NORTHERN INDIANA. SO FOR THAT REASON AND REPORTS RECEIVED THROUGH DISPATCH...HAVE DOWNGRADED THOSE SOUTHERN AREAS...AS BLOWING SNOW SHOULD BE QUITE LIMITED THIS MORNING. REMAINDER OF DISCUSSION FORTHCOMING... MTF && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 09Z... * MODERATE/HEAVY SNOW THROUGH 10Z-11Z WITH VLIFR CIGS/VIS. * LIGHT SNOW THROUGH 12Z-14Z. * STRONG/GUSTY NORTHERLY WINDS THROUGH MID/LATE AFTERNOON. * MVFR CIGS AFTER SNOW ENDS THROUGH MID AFTERNOON. CMS //DISCUSSION...UPDATED 09Z... NO SIGNIFICANT CHANGES WITH THE 09Z UPDATE. BACK EDGE OF MODERATE TO HEAVY SNOW NOW ALONG A MDW/JOT/C09 LINE AND SHIFTING EAST. BEHIND THIS LINE WILL BE A 2-3 HOUR PERIOD OF LIGHT SNOW WITH VIS GENERALLY AROUND 1SM. END OF THE SNOW NOW PUSHING ACROSS NORTHWEST IL AND WILL PASS ACROSS THE CHICAGO AREA TERMINALS BETWEEN 12Z-14Z. WINDS HAVE INCREASED WITH GUSTS ON ONE MINUTE DATA AT ORD/MDW CURRENTLY IN THE UPPER 20KT RANGE. SO GUSTS AROUND 30KTS ON TRACK FOR MUCH OF THE MORNING HOURS. CMS PREVIOUS 06Z DISCUSSION... PRECIPITATION HAS TRANSITIONED TO A WET SNOW ACROSS THE CHICAGO TERMINALS WITH A MIX OF RAIN STILL POSSIBLE ALONG A GYY/JOT LINE. LARGE AREA OF SNOW OVER SOUTHEAST IA/NORTHERN MO AND WESTERN IL WILL CONTINUE EAST/NORTHEAST ACROSS THE TERMINALS THROUGH THE EARLY MORNING HOURS WITH PREVAILING MODERATE SNOW EXPECTED. PERIODS/BURSTS OF HEAVY SNOW ALSO POSSIBLE AND MAINTAINED PREVIOUS TEMPO. WITH A SHARP EDGE EXPECTED ALONG THE NORTHERN EDGE OF THE SNOW...PREVAILING VISIBILITIES AT ORD/DPA COULD BE A BIT HIGHER THAN ADVERTISED AND WILL NEED TO MONITOR TRENDS OVER THE NEXT FEW HOURS. STILL A FEW LIGHTNING STRIKES...AT TIMES...WHICH WILL BE POSSIBLE IN THE BURSTS OF HEAVIER SNOW BUT EXPECTED COVERAGE TOO LOW FOR MENTION IN THE FORECAST. SHORT TERM/HI RES GUIDANCE IN GOOD AGREEMENT WITH THE HEAVIEST SNOW SHIFTING EAST OF THE CHICAGO TERMINALS 10Z-11Z WITH RAPID IMPROVEMENT IN BOTH CIGS AND VIS EXPECTED IN THE 11Z-13Z TIME PERIOD. FURTHER NORTHWEST AT RFD...PERIOD OF LIGHT SNOW STILL POSSIBLE FOR A FEW HOURS...BUT HEAVIER SNOW AND LOWER CONDITIONS APPEAR TO REMAIN SOUTH OF RFD. NORTH/NORTHEAST WINDS HAVE BEEN GUSTING INTO THE 20-25KT RANGE AT TIMES BUT ONE MINUTE DATA AT ORD/MDW HAVE BEEN RELATIVELY GUST FREE SINCE PRECIP HAS CHANGED OVER TO SNOW. WINDS WILL INCREASE OVERNIGHT...BUT NOT QUITE AS FAST OR STRONG AS PREVIOUSLY EXPECTED. STRONGEST WINDS LIKELY TO OCCUR AFTER SNOW ENDS AND CONTINUE FOR MUCH OF THE DAY WITH NORTHERLY DIRECTIONS. SNOW IS FAIRLY WET WITH TEMPS STILL IN THE LOWER 30S AND WITH EXPECTED LOWER SPEEDS/GUSTS DURING MUCH OF THE FALLING SNOW...HAVE REMOVED BLOWING SNOW...WHICH MAY STILL BE POSSIBLE WITH ANY LIGHTER/DRIER SNOW THAT FALLS AS SNOWFALL IS ENDING TOWARD DAYBREAK. CMS //ORD AND MDW CONFIDENCE...UPDATED 09Z... * HIGH FOR SNOW/CIG/VIS TRENDS. * MEDIUM FOR WIND SPEEDS/GUSTS/DIRECTIONS AND TIMING. * MEDIUM FOR MVFR CIGS INTO THIS AFTERNOON. CMS //OUTLOOK FOR ORD/MDW FOR 12Z THURSDAY-12Z TUESDAY...UPDATED 00Z... * THURSDAY...DRY/VFR. GUSTY SOUTHWEST WINDS. * FRIDAY...DRY/VFR. GUSTY WESTERLY WINDS. * SATURDAY...DRY/VFR. * SUNDAY...SLIGHT CHANCE OF SNOW. * MONDAY...DRY/VFR. KJB && .MARINE... 410 AM...LOW PRESSURE OVER SOUTHERN INDIANA WILL DEEPEN THROUGH TONIGHT WHEN IT REACHES NEW ENGLAND. THE GRADIENT WILL REMAIN TIGHT AS HIGH PRESSURE BUILDS ACROSS THE UPPER MIDWEST AND ONTARIO. GALE FORCE WINDS WILL SLOWLY DIMINISH FROM THE NORTH THIS AFTERNOON TO THE SOUTH EARLY THIS EVENING. WINDS THEN QUICKLY DIMINISH AFTER MIDNIGHT AS THE RIDGE PASSES OVER THE LAKE. WINDS TURN BACK SOUTHWESTERLY ON THE BACK SIDE OF THE DEPARTING HIGH WITH A PERIOD OF 30KTS EXPECTED THURSDAY INTO THURSDAY NIGHT AS LOW PRESSURE MOVES ACROSS THE UPPER LAKES THURSDAY NIGHT INTO FRIDAY. A TRAILING COLD FRONT WILL PUSH ACROSS THE LAKES FRIDAY AFTERNOON. A LARGE HIGH WILL SETTLE ACROSS THE LAKES REGION SUNDAY INTO SUNDAY NIGHT. CMS && .LOT WATCHES/WARNINGS/ADVISORIES... IL...WINTER STORM WARNING...ILZ013-ILZ014-ILZ020-ILZ021-ILZ022-ILZ023 UNTIL 11 AM WEDNESDAY. WINTER WEATHER ADVISORY...ILZ006-ILZ011-ILZ012 UNTIL 7 AM WEDNESDAY. WINTER WEATHER ADVISORY...ILZ019-ILZ032-ILZ033-ILZ039 UNTIL 11 AM WEDNESDAY. IN...WINTER STORM WARNING...INZ001-INZ002 UNTIL 11 AM WEDNESDAY. WINTER WEATHER ADVISORY...INZ010-INZ011-INZ019 UNTIL 11 AM WEDNESDAY. LM...GALE WARNING...LMZ080-LMZ669-LMZ671-LMZ673-LMZ675-LMZ740-LMZ741- LMZ742-LMZ743-LMZ744-LMZ745-LMZ777-LMZ779-LMZ870-LMZ872- LMZ874-LMZ876-LMZ878 UNTIL 10 PM WEDNESDAY. GALE WARNING...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-LMZ567- LMZ868 UNTIL 7 PM WEDNESDAY. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
351 AM CDT WED MAR 12 2014 .MESOSCALE DISCUSSION... 350 AM CDT HAVE MADE SOME ADJUSTMENTS TO HEADLINES...NAMELY TO BRING UP EXPIRATION TIMES...INCLUDING WARNING FOR THE CHICAGO AREA. ALSO DID DOWNGRADE THE WARNING IN A HANDFUL OF COUNTIES THAT EITHER 1. RECEIVED CONSIDERABLY LESS SNOWFALL THAN ORIGINALLY FORECAST OR 2. WILL HAVE AN EARLIER END TIME WITH LESS BLOWING SNOW THAN INITIALLY THOUGHT AND THUS IMPACTS AFTER SUNRISE WILL BE CONSIDERABLY LESS...SO DID NOT FEEL WARNING WAS ANY LONGER APPROPRIATE FOR THOSE AREAS. THE VERY WELL-DEFINED UPPER LOW IS ENTERING WESTERN IL AS OF 330 AM WITH FURTHER AMPLIFICATION OCCURRING AS NORTHERN STREAM SHORT WAVE FROM MN DIGS SOUTHEAST TOWARD/INTO THIS SYSTEM. THE DEFORMATION AREA SEEMS TO BE FOLLOWING SUIT...WITH INCREASED REFLECTIVITY SINCE 300 AM IN A SOUTHWEST TO NORTHEAST CORRIDOR ALIGNING WITH FRONTOGENESIS...INCLUDING OVER CHICAGO. HAVE HAD A COUPLE LIGHTNING STRIKES NEAR PONTIAC IN THE PAST COUPLE HOURS AND JUST PRIOR TO THAT SEVERAL REPORTS THROUGH SOCIAL MEDIA OF HEARING THUNDER. SO SOME EMBEDDED HEAVIER RATES ARE LIKELY WITHIN THIS AXIS GIVEN REFLECTIVITY AND JUST WHAT IS OCCURRING OUT THE WINDOW IN ROMEOVILLE...INCLUDING WITH LARGE FLAKES COMMON OF HIGH MIXING RATIO SCENARIOS. CONTINUE THE WARNING FOR THE CHICAGO METRO AREA AND FAR NORTHWEST INDIANA BUT MOVE UP THE EXPIRATION TIME TO 11 AM...AND IT COULD END UP BEING CANCELLED EVEN EARLIER IF BLOWING SNOW AND ATTENDANT IMPACTS ARE DETERMINED TO BE LESS. FURTHER TO THE SOUTHEAST...MAINLY SOUTH OF A PONTIAC TO RENSSELAER LINE...GREATER ELEVATED INSTABILITY IS PRESENT PER LOOK OF RADAR ECHOES AND RAP ANALYSIS. MUCH OF THIS AREA HOWEVER CHANGED OVER TO ALL SNOW ONLY AT 2-330 AM AND THUS ACCUMULATIONS LOOK LIMITED...WHICH WE KNEW WOULD COULD OCCUR. SOME OF THE HEAVIEST CONVECTION JUST MISSED OVERRIDING THIS AREA HAS NOW SKIRTED INTO NORTHERN INDIANA. SO FOR THAT REASON AND REPORTS RECEIVED THROUGH DISPATCH...HAVE DOWNGRADED THOSE SOUTHERN AREAS...AS BLOWING SNOW SHOULD BE QUITE LIMITED THIS MORNING. REMAINDER OF DISCUSSION FORTHCOMING... MTF && .DISCUSSION... 905 PM CDT NO CHANGES PLANNED WITH THE CURRENT HEADLINES. THE LOW PRESSURE HAS PUSHED EAST INTO CENTRAL MISSOURI THIS EVENING...AND CONTINUES TO SLOWLY SLIDE EAST TO NORTHEAST. PRECIPITATION HAS TAKEN JUST A LITTLE LONGER TO DEVELOP...HOWEVER LOCAL RADAR INDICATES SEVERAL AREAS BEGINNING TO DEVELOP. IN ADDITION SOME CONVECTION HAS DEVELOPED THIS EVENING AS WELL ACROSS THE FORECAST AREA...MAINLY SOUTH OF I-88 IN NORTHERN IL. DUE TO THE LOW TOPPED NATURE OF THESE THUNDERSTORMS...REPORTS OF PEA SIZE HAIL. TEMPERATURES WILL BEGIN TO FALL...WHICH WILL LIKELY ALLOW A TRANSITION TOWARDS SNOW LATER THIS EVENING. ONE ITEM THAT HAS BEEN UPDATED FOR TONIGHT WAS TO INCLUDE THE MENTION OF SLT CHC THUNDER FOR AREAS ALONG AND SOUTH OF I-80 IN NORTHERN IL/NORTHWEST IN. IT IS POSSIBLE THAT ONCE THE STEADY HEAVY SNOW GETS GOING...THAT GIVEN HOW UNSTABLE THE ENVIRONMENT REMAINS...THAT THUNDERSNOW MAY OCCUR IN A FEW LOCATIONS ACROSS NORTHEAST IL/NORTHWEST IN...JUST SOUTH OF CHICAGO. BEACHLER //PREV DISCUSSION... 355 PM CDT HEADLINES...UPGRADED THE SOUTHEASTERN COUNTIES FROM A WINTER STORM WATCH TO A WINTER STORM WARNING. OTHERWISE NO CHANGES WERE MADE TO THE HEADLINES. REST OF TODAY THROUGH WEDNESDAY AFTERNOON... AN UPPER LEVEL TROUGH AXIS STRETCHES FROM HUDSON BAY THROUGH THE NORTHERN ROCKIES...WITH ANOTHER WEAK SHORTWAVE IS MOVING INTO NORTH DAKOTA AND NORTHERN MINNESOTA. THE SURFACE LOW IS OVER SOUTHEASTERN KANSAS AND IS BEGINNING TO DEEPEN. A STATIONARY FRONT IS OVER THE FAR SOUTHERN SECTION OF THE CWA...AND STRETCHING FROM NORTHERN MO THROUGH LOGANSPORT INDIANA. TEMPS HAVE BEEN RATHER IMPRESSIVE TODAY GIVEN THE CLOUD COVER. EVERYWHERE JUMPED TO AT LEAST 40 WITH AREAS SOUTH OF I-88 REACHING INTO THE UPPER 40S TO AROUND 60 IN CENTRAL IL. EVEN SEEING 40 DEGREE TEMPS THROUGHOUT SOUTHERN WI DESPITE THE NORTHERLY WINDS. AS WINDS BECOME NORTH ACROSS THE CWA WILL SEE TEMPS START TO FALL THIS AFTERNOON. MAY HAVE TOO QUICK OF A TREND IN THE GRIDS...BUT EXPECTING TEMPS TO FALL PRETTY QUICKLY. THE LOW WILL CONTINUE TO DEEPEN AS IT CROSSES OVER SOUTHERN IL AND CONTINUES EAST INTO THE UPPER OHIO RIVER VALLEY TOMORROW AFTERNOON. HIGH PRESSURE IS CENTERED OVER MANITOBA AND IT WILL MOVE OVER SW ONTARIO BY TOMORROW MORNING. AS SUCH THE PRESSURE GRADIENT WILL TIGHTEN OVERNIGHT RESULTING IN STRONG WINDS. IN GENERAL WINDS WILL BE 20-30 MPH WITH GUSTS UP TO 40 MPH. THE STRONGEST GUSTS...UP TO 45 MPH...WILL BE ALONG THE LAKESHORE. RIGHT NOW THERE IS A BAND OF LIGHT RAIN OVER SOUTHERN WI AND A FEW STRAY ECHOES OVER NW ILLINOIS. EXPECTING THAT BAND TO SLOWLY SHIFT SOUTH INTO NORTHERN IL LATE THIS AFTERNOON AND INITIALLY FALL AS RAIN. EXPECTING SNOW TO SPREAD ACROSS THE CENTRAL AND SOUTHWESTERN PORTIONS OF THE CWA THIS EVENING AS THE LOW MOVES OVER SOUTHERN IL. AT THE SAME TIME...THE MAIN TROUGH AXIS AND ASSOCIATED VORT STREAMER WILL BE MOVING OVER THE MISSISSIPPI RIVER BRINGING IMPRESSIVE FORCING TO THE REGION. GUIDANCE INDICATES THERE WILL BE A BAND OF FRONTOGENESIS ASSOCIATED WITH NEGATIVE EPV ROUGHLY ALONG THE I-55 CORRIDOR. ADDITIONAL FORCING WILL BE PROVIDED BY THE UPPER LEVEL JET. WE WILL BE UNDER THE LEFT EXIT REGION OF THE JET STREAK ASSOCIATED WITH THE DEEPENING LOW...AND THEN AT THE NOSE OF THE JET PUSHING IN FROM THE NORTH. ALL OF THIS FORCING IS OVER THE DGZ...WHICH VARIES FROM 100MB TO 200MB DEEP. THEREFORE...KEPT THE SAME IDEA AS THE PREVIOUS FORECAST WITH THE MAJORITY OF SNOW FALLING OVERNIGHT TONIGHT. RATES OF 1-2 INCHES PER HOUR ARE EXPECTED ALONG AND EAST OF I-55. LEFT THUNDERSNOW OUT OF THE FORECAST BECAUSE DO NOT HAVE ENOUGH CONFIDENCE IN IT. FORECAST SOUNDINGS FEATURE MINIMUM CAPE VALUES...LESS THAN 50 J/KG. MAY SEE A RANDOM STRIKE OF LIGHTNING ASSOCIATED WITH THE HEAVY SNOW...BUT NOT EXPECTING AN ABUNDANCE OF THUNDERSNOW. THEREFORE THE WINTER STORM WARNING IS FOR PERIODS OF HEAVY SNOW AND NEAR BLIZZARD LIKE CONDITIONS WITH THE GUSTY WINDS. VISIBILITIES AT OR BELOW A QUARTER OF A MILE ARE POSSIBLE OVERNIGHT AND INTO THE PRE-DAWN HOURS WEDNESDAY MORNING. THE MORNING COMMUTE WILL PROBABLY BE IMPACTED BY THE LINGERING SNOW AND GUSTY WINDS. EVEN IF IT IS NOT SNOWING THAT HARD DURING THE COMMUTE...THE GUSTY WINDS WILL LIKELY BE BLOWING SNOW AROUND AND REDUCING VISIBILITY. SNOW INTENSITY DWINDLES TOMORROW MORNING AS FORCING AND SATURATION IN THE DGZ BOTH DIMINISH. AS THE TROUGH MOVES THROUGH...THE SNOW ENDS FROM WEST TO EAST. MAY SEE SOME LIGHT SNOW PERSIST OVER NORTHWEST INDIANA AFTER THE WARNING EXPIRES...BUT THINKING THE MAIN SHOW WILL BE OVER. SNOW TOTALS WILL VARY FROM 2 TO 4 INCHES ACROSS THE IL/WI STATE LINE TO 4 TO 8 INCHES ALONG AND SOUTH OF I-88. MAY SEE A FEW LOCALLY HIGHER TOTALS ESPECIALLY IF WE SEE SOME THUNDERSNOW. WINDS WILL BE DUE NORTH DOWN THE LAKE AND MAY SEE A FEW LIGHT SNOW SHOWERS PRIMARILY OVER NORTHWEST INDIANA IN THE AFTERNOON. DO NOT THINK THE SHOWERS WILL AMOUNT TO MUCH WITH THE EXTENSIVE ICE COVER OVER THE LAKE. ALSO MAY SEE A FEW STRAY LIGHT SNOW SHOWERS OVER THE WESTERN CWA LATE WEDNESDAY MORNING INTO EARLY WEDNESDAY AFTERNOON AS ANOTHER VORT STREAMER MOVES THROUGH THE REGION. CONFIDENCE IS LOW WITH THESE SNOW SHOWERS AS THE FORCING AND MOISTURE DO NOT LOOK OVERLY IMPRESSIVE AT THIS TIME. AS MENTIONED ABOVE...TEMPS WILL FALL LATER THIS AFTERNOON THROUGH THIS EVENING WITH OVERNIGHT LOWS IN THE 20S. WITH THE STRONG WINDS...WIND CHILLS WILL BE IN THE SINGLE DIGITS TONIGHT. TEMPS WILL NOT REBOUND MUCH TOMORROW WITH THE HIGH TEMP BEING REACHED IN THE MORNING. THE COLD AIR ASSOCIATED WITH THE TROUGH MOVES OVER THE REGION DURING THE DAY...SO HIGH TEMPS WILL BE IN THE 20S. WIND CHILLS WILL MAKE IT FEEL LIKE +10 OR LOWER. WEDNESDAY NIGHT AND THURSDAY... THE TROUGH SHIFTS EAST WEDNESDAY NIGHT AND UPPER LEVEL TEMPS BEGIN TO RISE. OVERNIGHT LOWS WILL BE IN THE SINGLE DIGITS...EXCEPT 10-15 DEGREES OVER THE CITY. WIND CHILLS WILL BE AROUND ZERO WITH SOME OUTLYING AREAS GETTING AS LOW AS -5. THERE IS A SLIGHT CHANCE OF LIGHT SNOW NORTH OF I-88 THURSDAY MORNING AS A WEAK WARM FRONT MOVES INTO THE REGION. FORCING DOES NOT LOOK IMPRESSIVE WITH THE FRONT SO HAVE LOW CONFIDENCE IN THIS CHANCE OF SNOW. HIGH TEMPS ON THURSDAY WILL BE IN THE 30S DUE TO WAA ASSOCIATED WITH THE FRONT. THE WARMING TREND CONTINUES OVERNIGHT WITH LOWS AROUND 30. JEE && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 06Z... * HEAVY SNOW THROUGH 10Z-11Z WITH VLIFR CIGS/VIS. * STRONG/GUSTY NORTHERLY WINDS THROUGH MID/LATE AFTERNOON. * MVFR CIGS AFTER SNOW ENDS THROUGH MID AFTERNOON. CMS //DISCUSSION...UPDATED 06Z... PRECIPITATION HAS TRANSITIONED TO A WET SNOW ACROSS THE CHICAGO TERMINALS WITH A MIX OF RAIN STILL POSSIBLE ALONG A GYY/JOT LINE. LARGE AREA OF SNOW OVER SOUTHEAST IA/NORTHERN MO AND WESTERN IL WILL CONTINUE EAST/NORTHEAST ACROSS THE TERMINALS THROUGH THE EARLY MORNING HOURS WITH PREVAILING MODERATE SNOW EXPECTED. PERIODS/BURSTS OF HEAVY SNOW ALSO POSSIBLE AND MAINTAINED PREVIOUS TEMPO. WITH A SHARP EDGE EXPECTED ALONG THE NORTHERN EDGE OF THE SNOW...PREVAILING VISIBILITIES AT ORD/DPA COULD BE A BIT HIGHER THAN ADVERTISED AND WILL NEED TO MONITOR TRENDS OVER THE NEXT FEW HOURS. STILL A FEW LIGHTNING STRIKES...AT TIMES...WHICH WILL BE POSSIBLE IN THE BURSTS OF HEAVIER SNOW BUT EXPECTED COVERAGE TOO LOW FOR MENTION IN THE FORECAST. SHORT TERM/HI RES GUIDANCE IN GOOD AGREEMENT WITH THE HEAVIEST SNOW SHIFTING EAST OF THE CHICAGO TERMINALS 10Z-11Z WITH RAPID IMPROVEMENT IN BOTH CIGS AND VIS EXPECTED IN THE 11Z-13Z TIME PERIOD. FURTHER NORTHWEST AT RFD...PERIOD OF LIGHT SNOW STILL POSSIBLE FOR A FEW HOURS...BUT HEAVIER SNOW AND LOWER CONDITIONS APPEAR TO REMAIN SOUTH OF RFD. NORTH/NORTHEAST WINDS HAVE BEEN GUSTING INTO THE 20-25KT RANGE AT TIMES BUT ONE MINUTE DATA AT ORD/MDW HAVE BEEN RELATIVELY GUST FREE SINCE PRECIP HAS CHANGED OVER TO SNOW. WINDS WILL INCREASE OVERNIGHT...BUT NOT QUITE AS FAST OR STRONG AS PREVIOUSLY EXPECTED. STRONGEST WINDS LIKELY TO OCCUR AFTER SNOW ENDS AND CONTINUE FOR MUCH OF THE DAY WITH NORTHERLY DIRECTIONS. SNOW IS FAIRLY WET WITH TEMPS STILL IN THE LOWER 30S AND WITH EXPECTED LOWER SPEEDS/GUSTS DURING MUCH OF THE FALLING SNOW...HAVE REMOVED BLOWING SNOW...WHICH MAY STILL BE POSSIBLE WITH ANY LIGHTER/DRIER SNOW THAT FALLS AS SNOWFALL IS ENDING TOWARD DAYBREAK. CMS //ORD AND MDW CONFIDENCE...UPDATED 06Z... * HIGH FOR SNOW/CIG/VIS TRENDS. * MEDIUM FOR WIND SPEEDS/GUSTS/DIRECTIONS AND TIMING. * MEDIUM FOR MVFR CIGS INTO THIS AFTERNOON. CMS //OUTLOOK FOR ORD/MDW FOR 12Z THURSDAY-12Z TUESDAY...UPDATED 00Z... * THURSDAY...DRY/VFR. GUSTY SOUTHWEST WINDS. * FRIDAY...DRY/VFR. GUSTY WESTERLY WINDS. * SATURDAY...DRY/VFR. * SUNDAY...SLIGHT CHANCE OF SNOW. * MONDAY...DRY/VFR. KJB && .MARINE... 210 PM CDT LOW PRESSURE OVER THE CENTRAL PLAINS WILL CONTINUE TO DEEPEN AS IT TRACKS EAST ACROSS SOUTHERN ILLINOIS TONIGHT AND INTO THE OHIO VALLEY WEDNESDAY. AS THE LOW TRACKS SOUTH AND THEN SOUTHEAST OF THE LAKE...HIGH PRESSURE WILL ALSO BUILD ACROSS THE UPPER GREAT LAKES REGION...SETTING UP STRONG NORTH WINDS. THE COMBINATION OF A STRONG GRADIENT AND STRONG COLD ADVECTION WILL LEAD TO WINDS QUICKLY INCREASING TO GALES BY LATE THIS EVENING. THE LATEST GUIDANCE HAS BEEN RELATIVELY CONSISTENT IN INDICATING THE POTENTIAL FOR HIGH END GALES BY LATE WEDNESDAY MORNING AND EARLY AFTERNOON...WITH THE STRONGEST GALES OVER THE SOUTHERN PORTIONS OF THE LAKE...INCLUDING THE NEARSHORE WATERS. BY WEDNESDAY EVENING...THE HIGH PRESSURE WILL BEGIN TO SPREAD ACROSS LAKE MICHIGAN ALLOWING WINDS TO SUBSIDE BELOW GALE FORCE. BY THURSDAY NIGHT...THE HIGH WILL PUSH TO THE SOUTHEAST OF THE LAKE AS A CLIPPER DROPS OUT OF NORTHERN ALBERTA AND SWINGS JUST NORTH OF THE UPPER GREAT LAKES ON FRIDAY. WITH THE SFC HIGH SAGGING OFF THE SERN COAST...A PERIOD OF SWLY WINDS WILL DEVELOP AHEAD OF AN APPROACHING COLD FRONT TRAILING FROM THE CLIPPER. ANTICIPATE A PERIOD OF BRISK SLY TO SWLY WINDS FOR THURSDAY NIGHT THROUGH FRIDAY...BUT MORE GALES ARE NOT EXPECTED AT THIS TIME. AS THE CLIPPER TURNS NEWD INTO QUEBEC...IT WILL DRAG A WEAK COLD FRONT DOWN THE LAKE WITH ANOTHER ARCTIC HIGH BUILDING IN BEHIND THE FRONT. 25-30KT NORTH WINDS WILL SET UP FOLLOWING THE FROPA FOR SATURDAY NIGHT AND SUNDAY...BUT AS THE HIGH SPREADS ACROSS THE GREAT LAKES SUNDAY NIGHT...WINDS SHOULD BECOME MORE LIGHT AND VARIABLE. KREIN && .LOT WATCHES/WARNINGS/ADVISORIES... IL...WINTER STORM WARNING...ILZ013-ILZ014-ILZ020-ILZ021-ILZ022-ILZ023 UNTIL 11 AM WEDNESDAY. WINTER WEATHER ADVISORY...ILZ006-ILZ011-ILZ012 UNTIL 7 AM WEDNESDAY. WINTER WEATHER ADVISORY...ILZ019-ILZ032-ILZ033-ILZ039 UNTIL 11 AM WEDNESDAY. IN...WINTER STORM WARNING...INZ001-INZ002 UNTIL 11 AM WEDNESDAY. WINTER WEATHER ADVISORY...INZ010-INZ011-INZ019 UNTIL 11 AM WEDNESDAY. LM...GALE WARNING...LMZ080-LMZ669-LMZ671-LMZ673-LMZ675-LMZ740-LMZ741- LMZ742-LMZ743-LMZ744-LMZ745-LMZ777-LMZ779-LMZ870-LMZ872- LMZ874-LMZ876-LMZ878 UNTIL 10 PM WEDNESDAY. GALE WARNING...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-LMZ567- LMZ868 UNTIL 7 PM WEDNESDAY. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS TOPEKA KS
1159 PM CDT Tue Mar 11 2014 ...Update to aviation forecast discussion... .SHORT TERM...(This Evening through Tonight) Issued at 322 PM CDT TUE MAR 11 2014 Late this afternoon, surface boundary bisects the CWA stretching just west of Wichita to the northeast to Topeka and further east north of KM CI. Several convergence zones ahead this boundary, with strongest axis stretching along the I-35/335 corridor. Will need to watch for potential development of convection along this corridor through 6pm as primary cold front moves east. Instability along and head of this front remains meager, with RAP analysis only indicating CAPE values 100-300 J/KG. If storms would happen to develop, the main impact would be small hail with the longevity of convection in the CWA minimal. The other concern heading into the overnight hours will be strong gradient winds. We`re already seeing advisory level winds in the far NW portion of the CWA at this hour, and as the surface boundary settles southeast, these strong gradient winds will swing through the CWA. By midnight, sfc pressure gradient should begin to weaken as the developing sfc low moves through the MO bootheel. The shortwave responsible for these strong winds and increasing precipitation chances is just beginning to enter the Western Plains this afternoon. A linear band of mid-level frontogenesis across NE/IA slopes back to western KS at 3pm. Short term model guidance continues to suggest that this band will slowly move southeast this evening. While the western flank of the mid-level lift should hold together the further southeast it tracks, the eastern areas of precip across NE/IA will dissipate as a new baroclinic zone is reestablished further south across eastern KS and northern Missouri. Precipitation should blossom shortly after 00Z along the eastern edges of the CWA. Given the position of the shortwave and how the wave pivots eastward, the majority of the heavy precipitation should take place just east of the CWA. Latest hopWRF, HRRR, RAP support the idea of a brief window of 3-5 hrs of a rain/snow mixture bisecting the CWA with most of the activity diminishing or moving east by 1am. Accumulations should remain light given the warm grounds, but could see up to an inch of snow in some spots where efficient rates can overtake boundary layer temps. .LONG TERM...(Wednesday Night through Tuesday) Issued at 322 PM CDT TUE MAR 11 2014 After the past two days, Wednesday will feel chilly with temperatures rebounding into the upper 40s to lower 50s. Will watch for an increase in low-level clouds late morning, as a secondary wave rotates southward into the area. A quick rebound above normal is expected by Thursday and Friday ahead of yet another shortwave pivoting through the southern Rockies. Temperatures on Thursday will rebound into the 60s, with a front dropping southward on Friday lowering readings a few degrees. Saturday-Monday: The aforementioned shortwave should pass far enough to the south Friday night to have minimal impact on the CWA leaving conditions pleasant for Saturday. A slightly more amplified flow pattern will drop colder air southward again on Sunday, but this cooldown should last no longer than a day as increasing southwesterly flow ushers above normal temperatures into the region to begin next week. Have bumped up temperatures for Monday. && .AVIATION...(For the 06Z TAFs through 06Z Wednesday Night) Issued at 1141 PM CDT TUE MAR 11 2014 Kept mention of light rain/snow mix at TOP and FOE for another hour as last band progged to pass through in that timeframe. Low cigs also move out quickly and brought vfr back to sites by 07z as well. Winds remain northwest with some gusts overnight but can likely be diminished and backed with the next taf issuance late in the forecast period. && .TOP WATCHES/WARNINGS/ADVISORIES... WIND ADVISORY until 1 AM CDT Wednesday FOR KSZ011-012-022>024- 026-036>040-054>056-058-059. && $$ SHORT TERM...DUX LONG TERM...DUX AVIATION...67
AREA FORECAST DISCUSSION
NWS GRAY ME
358 AM EDT WED MAR 12 2014 .SYNOPSIS... LOW PRESSURE WILL MOVE NORTHEAST OUT OF THE OHIO VALLEY TODAY AND WILL RAPIDLY INTENSIFY AS IT MOVES OFF THE NEW ENGLAND COAST OVERNIGHT. LOW PRESSURE WILL CONTINUE NORTHEAST THROUGH THE MARITIMES ON THURSDAY. A RIDGE OF HIGH PRESSURE WILL BUILD IN FROM THE WEST THURSDAY NIGHT. HIGH PRESSURE WILL MOVE OFFSHORE ON FRIDAY AS A WARM FRONT LIFTS INTO THE REGION FROM THE SOUTHWEST. A COLD FRONT WILL APPROACH FROM THE WEST FRIDAY NIGHT AND SATURDAY AND WILL SLOWLY CROSS THE REGION SATURDAY NIGHT. HIGH PRESSURE WILL GRADUALLY BUILD IN FROM THE WEST SUNDAY THROUGH MONDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... VERY TRICKY AND LOW CONFIDENCE FORECAST CONTINUES FOR THE COASTAL PLAIN TODAY. MUCH OF THE 00Z GUIDANCE HAS WARMED FOR TODAY...BASICALLY CATCHING UP TO WHAT THE ECMWF HAS BEEN SHOWING FOR AWHILE NOW. THIS HAS RESULTED IN THE ADJUSTMENT OF THE TIMING OF SOME OF THE WARNINGS AND ADVISORIES. AS A RESULT OF THE COLUMN WARNING ACROSS SOUTHERN AREAS TODAY...THE MID LEVEL FRONTOGENETICAL ZONE WILL BE PUSHED NORTH. THE RESULT SHOULD BE A NORTHWARD PUSH OF THE MODERATE TO HEAVY PRECIPITATION INTO THE MOUNTAINS AND FOOTHILLS FOR MUCH OF THE DAY. IN FACT...THE LATEST HRRR AND RAP HAVE LITTLE IN THE WAY OF PRECIPITATION TODAY ACROSS SOUTHERNMOST PORTIONS OF NH AND ME THROUGH AT LEAST 21Z. THEREFORE...THE LIGHT NATURE OF THE PRECIPITATION COMBINED WITH A WARMING COLUMN SHOULD NOT ALLOW FOR WIDESPREAD HAZARDOUS WEATHER CONDITIONS THERE DURING MUCH OF THE DAY TODAY NEAR THE COAST. IN FACT...JUST A LIGHT TO OCCASIONALLY MODERATE RAIN MIXED WITH SNOW AND SLEET AT TIMES SEEMS TO BE THE MOST LIKELY SCENARIO ALONG COASTAL ME SOUTHWESTWARD TO MUCH OF SOUTHERN NH. CONSIDERED DOWNGRADING THE WARNINGS TO ADVISORIES IN THESE AREAS...BUT SINCE COLD AIR IS EXPECTED TO RAPIDLY MOVE IN TONIGHT RESULTING IN A HEAVY MIXED BAG OF SNOW...SLEET...AND FREEZING RAIN COMBINED WITH STRONG WINDS...FELT IS WAS BEST TO KEEP THE WARNINGS GOING. A FLASH FREEZE WILL BE POSSIBLE THIS EVENING AT LOCATIONS THAT HOLD ONTO ABOVE FREEZING TEMPS TODAY. WE/VE RADIATED DOWN TO AROUND FREEZING EARLY THIS WEDNESDAY MORNING...AND THIS SHOULD RESULT IN SOME FROZEN/FREEZING PRECIPITATION EARLY ON. MAY ADDRESS THIS WITH AN SPS DEPENDING ON HOW THE RADAR LOOKS IN A FEW HOURS. IN THE MOUNTAINS AND FOOTHILLS...EXPECT HEAVY SNOW TODAY...POSSIBLY MIXED WITH SLEET. IN THE TRANSITION AREA BETWEEN THE FOOTHILLS AND THE COASTAL PLAIN /EG...INTERIOR CUMBERLAND COUNTY ME/...EXPECT OSCILLATING PRECIPITATION TYPES MAKING FOR HAZARDOUS DRIVING CONDITIONS TODAY. A VERY CHANGEABLE SITUATION IS EXPECTED TODAY...AND THEREFORE FORECAST ADJUSTMENTS ARE LIKELY. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/... AS STRONG LOW PRESSURE PULLS INTO THE GULF OF MAINE TONIGHT...LOW LEVEL COLD AIR SHOULD RACE SOUTHEASTWARD TOWARD THE COAST. THIS SHOULD CHANGE ANY RAIN OR RAIN/SLEET MIX TO A MIX OF SNOW...SLEET...AND FREEZING RAIN. CURRENTLY FORECASTING UP TO A QUARTER INCH OF ICE FOR THE COASTAL PLAIN TONIGHT BEFORE THE COLUMN COOLS ENOUGH TO SUPPORT ALL SNOW. WINDS ARE EXPECTED TO INCREASE THIS EVENING AND GUST UP TO 45 MPH. THEREFORE...AREAS THAT SEE A WET SNOW AND/OR FREEZING RAIN MAY HAVE TO DEAL WITH POWER OUTAGES AS THE NIGHT WEARS ON. THD SNOW SHOULD TAPER OFF THURSDAY MORNING AND END BY EARLY AFTERNOON...LEAVING VERY COLD AIR IN THE STORMS WAKE FOR THE BALANCE OF THE DAY. && .LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/... LOW PRESSURE WILL PULL AWAY THURSDAY NIGHT FOLLOWED BY A NARROW RIDGE OF HIGH PRESSURE. EXPECT ANY LINGERING SNOW SHOWERS TO QUICKLY COME TO AN END THURSDAY EVENING AND SKIES WILL CLEAR AS HIGH PRESSURE BUILDS IN FROM THE WEST. TEMPERATURES WILL ONCE AGAIN END UP WELL BELOW NORMAL WITH LOWS OF ZERO TO AROUND 10 BELOW IN THE NORTH AND 5 BELOW TO 5 ABOVE IN THE SOUTH. LOW PRESSURE CROSSING SOUTHERN CANADA FRIDAY WILL LIFT A WARM FRONT INTO THE REGION IN THE AFTERNOON. WILL SEE INCREASING CLOUDS WITH A CHANCE OF SNOW SHOWERS...MAINLY IN NORTHWEST ZONES DURING THE LATE MORNING AND AFTERNOON. HIGH TEMPS WILL RANGE THROUGH THE 20S NORTH AND IN THE LOWER TO MID 30S SOUTH. PRE-FRONTAL TROUGH WILL BRING A CHANCE SNOW SHOWERS IN THE NORTH AND RAIN SHOWERS OR MIXED PRECIP IN THE SOUTH FRIDAY NIGHT. NOT A LOT FORCING WITH THIS BOUNDARY SO NOT LOOKING FOR MUCH IN THE WAY OF QPF. TROUGH PUSHES OFFSHORE EARLY SATURDAY MORNING AND SKIES SHOULD BECOME PARTLY TO MOSTLY SUNNY. COLD FRONT APPROACHING FROM THE NORTHWEST WILL BRING MORE CLOUDS INTO NORTHWEST ZONES IN THE AFTERNOON. EXPECT HIGHS RANGING THROUGH THE 40S. COLD FRONT WILL SLOWLY CROSS THE REGION SATURDAY NIGHT WITH LITTLE IF ANY FANFARE. WILL SEE THICKENING CLOUDS AND A CHANCE OF SNOW SHOWERS IN THE MOUNTAINS AND JUST VARIABLE CLOUDINESS ELSEWHERE. TEMPERATURES BY SUNDAY MORNING WILL RANGE FROM THE TEENS NORTH TO THE LOWER TO MID 20S SOUTH. SUNDAY LOOKING BREEZY AND COOLER BEHIND THE FRONT AS HIGH PRESSURE BUILDING IN FROM THE WEST SETS UP A TIGHT NORTHWESTERLY GRADIENT ACROSS THE REGION. EXPECT CLOUDS TO HANG TOUGH IN THE CONNECTICUT VALLEY AND THE MOUNTAINS THROUGH THE DAY WITH A MIX OF SUN AND CLOUDS ELSEWHERE. HIGH PRESSURE WILL CONTINUE TO BUILD IN FROM THE WEST SUNDAY NIGHT THROUGH MONDAY. HIGH PRESSURE WILL GRADUALLY SLIP OFFSHORE SOUTH OF NEW ENGLAND MONDAY NIGHT AS A WEAK WARM FRONT LIFTS NORTH INTO SOUTHERN CANADA NORTHWEST OF THE FORECAST AREA. WILL SEE INCREASING CLOUDS OVERNIGHT AND POSSIBLY A FEW SNOW SHOWERS ON TUESDAY AS WEAK OVER-RUNNING BRUSHES NORTHWEST ZONES. && .AVIATION /07Z WEDNESDAY THROUGH SUNDAY/... SHORT TERM...VFR CONDITIONS WILL DETERIORATE TO IFR OR LOWER BY THIS AFTERNOON IN SNOW OR MIXED PRECIPITATION. LIFR CONDITIONS ARE EXPECTED THROUGH TONIGHT INTO THURSDAY MORNING. WIND GUSTS UP TO 40 KT ARE EXPECTED TONIGHT WHICH WILL RESULT IN MECHANICAL TURBULENCE. LONG TERM...VFR THURSDAY NIGHT THROUGH SUNDAY. && .MARINE... SHORT TERM...GALES THIS AFTERNOON THROUGH THURSDAY IN ASSOCIATION WITH COASTAL STORM. LONG TERM...SCA`S LIKELY THURSDAY NIGHT AND FRIDAY NIGHT. GALES POSSIBLE SUNDAY NIGHT. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...WINTER STORM WARNING FROM 8 AM THIS MORNING TO NOON EDT THURSDAY FOR MEZ007>009-012>014. WINTER STORM WARNING FROM 11 AM THIS MORNING TO NOON EDT THURSDAY FOR MEZ018>022. WINTER STORM WARNING FROM 6 PM THIS EVENING TO NOON EDT THURSDAY FOR MEZ024>028. WINTER WEATHER ADVISORY FROM 6 PM THIS EVENING TO NOON EDT THURSDAY FOR MEZ023. NH...WINTER STORM WARNING FROM 8 AM THIS MORNING TO NOON EDT THURSDAY FOR NHZ001>007-009. WINTER STORM WARNING FROM 6 PM THIS EVENING TO NOON EDT THURSDAY FOR NHZ008-010. WINTER WEATHER ADVISORY FROM 6 PM THIS EVENING TO NOON EDT THURSDAY FOR NHZ013-014. MARINE...GALE WARNING FROM 4 PM THIS AFTERNOON TO 8 PM EDT THURSDAY FOR ANZ150>154. && $$ NEAR/SHORT TERM...MLE
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
514 AM EDT WED MAR 12 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 403 AM EDT WED MAR 12 2014 THE COLD FRONT THAT SHIFTED SOUTH ACROSS UPPER MICHIGAN LATE YESTERDAY AFTERNOON AND EVENING PRODUCED SNOW SHOWERS OVER MUCH OF WESTERN AND CENTRAL UPPER MICHIGAN...WITH THE STRONGEST SHOWERS SEEN OVER NORTH CENTRAL UPPER MICHIGAN. THIS WAS DUE TO THE NORTH TO NORTHEAST WINDS PROVIDING TERRAIN ENHANCEMENT TO THE LIGHTER SNOW SHOWERS AND ENDED UP PRODUCING ABOUT AN INCH OF SNOW AT OUR OFFICE THROUGH 2AM. THE INTENSITY HAS REALLY DIMINISHED OVER THE LAST HOUR OR TWO DUE TO THE DRY AIR (ASSOCIATED WITH THE HIGH OVER NORTHWEST ONTARIO) THAT HAS BEEN SURGING SOUTH ACROSS LAKE SUPERIOR ON IR SATELLITE. WITH LIMITED BREAKS IN THE ICE...THE COLD AIR (RAP ANALYZED 900MB TEMPERATURES OF -17C) HAS ONLY BEEN ABLE TO PRODUCE A COUPLE LAKE EFFECT CLOUD STREAMERS OFF THE OPEN AREA NEAR ISLE ROYALE AND THAT IS STRETCHING TOWARDS AREAS SOUTHWEST OF THE PORCUPINE MOUNTAINS. THIS DRYING ABOVE 900MB HAS LED TO SIGNIFICANT ADJUSTMENTS TO THE GOING FORECAST. SINCE THE HIGH WILL CONTINUE TO SLIDE SOUTHEAST OVER THE AREA THROUGH THE DAY TODAY...HAVE TRENDED THE FORECAST TOWARDS A FASTER END TO THE SNOW. WOULD EXPECT THE CLOUDS AND LIGHT SNOW SHOWERS OR FLURRIES TO REMAIN THE LONGEST OVER THE NORTH CENTRAL U.P. WHERE THE NORTHEAST WINDS WILL REMAIN MOST FAVORABLE. LOOKING AT 00Z NAM/GFS SOUNDINGS THEY DO HOLD ONTO MOISTURE RIGHT BELOW THAT INVERSION INTO THE AFTERNOON FOR KSAW...BUT THE LAST SEVERAL RAP RUNS REALLY SCOUR THAT MOISTURE OUT. THUS...WILL KEEP THE TREND TOWARDS PARTLY CLOUDY SKIES BY AFTERNOON OVER THE NORTH CENTRAL AND PARTLY CLOUDY TO MOSTLY SUNNY ELSEWHERE AWAY FROM THE UPSLOPE FLOW. AS FOR THE SNOW SHOWERS...HAVE CUT THAT BACK SIGNIFICANTLY...WITH THEM MAINLY BEING CONFINED TO THE NORTH CENTRAL FOR THE NEXT FEW HOURS AND THEN QUICKLY DIMINISHING DURING THE MORNING WITH THE WINDS STARTING TO BACK MORE TO THE NORTH-NORTHWEST. WILL MONITOR CLOUD/SNOW TRENDS THROUGH DAY BREAK AND MAY NEED TO DIMINISH THEM EVEN EARLIER THAN THE GOING FORECAST. WITH THE COLD AIR ALOFT THAT IS MOVING OVER THE AREA...EXPECT THE EARLY MORNING TEMPERATURES TO CONTINUE TO SLOWLY FALL. THE 3AM OBS (RANGING FROM 9 DEGREES IN COPPER HARBOR AND 27 IN MENOMINEE) WILL LIKELY BE THE WARMEST VALUES FOR THE RESPECTIVE LOCATIONS AND ONLY HAVE HIGHS IN THE UPPER SINGLE DIGITS TO THE NORTH AND THE MID TEENS TO THE SOUTH. AM A LITTLE CONCERNED THE WARM MARCH SUN THIS AFTERNOON COULD PRODUCE HIGHS A LITTLE WARMER THAN EXPECTED AND DID ADJUST INLAND WEST AREAS UP A COUPLE DEGREES TO ACCOUNT FOR THIS. FOR SEVERAL COOP SITES OVER THE WEST THAT REPORT ON A 7AM-7AM CYCLE...DAYTIME HIGHS TODAY COULD BE NEAR OR BREAK RECORD LOW HIGHS FOR THE OBS THAT WILL BE REPORTED ON MARCH 13TH. WITH THE HIGH BEING OVER DIRECTLY OVER THE U.P. THIS EVENING AND CLEAR SKIES...EXPECT TEMPERATURES TO QUICKLY DROP OVER THE WEST AND CENTRAL INITIALLY WITH THE LIGHT WINDS. THOSE AREAS SHOULD SEE THEIR LOWS EARLIER THAN THE EAST DUE TO THE HIGH SHIFTING SOUTHEAST OF THE AREA LATE TONIGHT AND ALLOWING SOUTHERLY FLOW TO DEVELOP. IN ADDITION...MID CLOUDS WILL BE ARRIVING OVER THE WEST LATE IN RESPONSE TO INCREASING WARM AIR ADVECTION ALOFT AND COULD EVEN LEAD TO SOME LIGHT SNOW SHOWERS OVER THE WESTERN QUARTER OF LAKE SUPERIOR BEFORE 12Z. OVER THE EAST...THE LATER WEAKENING OF THE WINDS SHOULDN/T HAVE MUCH AFFECT ON THE LOWS AND EXPECT THE LONGER RADIATIONAL COOLING TIME TO ALLOW LOWS TO EASILY FALL INTO THE TEENS BELOW ZERO. WILL CONTINUE TO FOLLOW THE NH/REGIONAL CANADIAN MODEL FOR TEMPERATURES OVER THE EAST...DUE TO IT/S GREAT PERFORMANCE THIS WINTER ON THESE TYPES OF NIGHTS. DID TREND LOWS DOWN A LITTLE FOR SOME OF THE TRADITIONAL COLD SPOTS (RAWS SITES LIKE DOE LAKE AND SPINCICH LAKE)...WHICH WILL LIKELY SEE VALUES FALLING INTO THE LOWER -20S. CURRENT FORECAST HAS LOWS NEARING/BREAKING RECORDS FOR MANISTIQUE (-7 IN 1948) AND MUNISING (-10 IN 1926). .LONG TERM...(THURSDAY THROUGH TUESDAY) ISSUED AT 513 AM EDT WED MAR 12 2014 THE OVERALL PATTERN WILL CONTINUE TO BE INFLUENCED BY RIDGING OVER WRN NOAM AND THE RESULTING DOWNSTREAM TROUGH INTO THE GREAT LAKES AND NERN CONUS...KEEPING TEMPS MAINLY BELOW NORMAL. A CLIPPER SHORTWAVE AND LOW MOVING THROUGH THE REGION WILL BRING A WARMUP FRIDAY WITH A CHANCE OF SOME LIGHT PCPN BUT WILL DRAG MUCH COLDER AIR INTO THE REGION IN ITS WAKE FOR THE WEEKEND. THU...AS ARCTIC HIGH PRES SHIFTS TO THE EAST AND MID LEVEL RIDGING BUILDS TOWARD THE UPPER MS VALLEY...WAA WILL SPREAD CLOUDS THROUGH UPPER MICHIGAN. ONLY SLIGHT CHANCE POPS FOR LIGHT SNOW WERE INCLUDED GIVEN ONLY LIMITED MOISTURE AVAILABILITY AND RELATIVELY SMALL NET ISENTROPIC LIFT AS THE 850-700 MB LAYER WARMS. A LARGE SPREAD OF HIGH TEMPS IS EXPECTED WITH READINGS RANGING FROM AROUND 20 NEAR ERY TO 40 AT IWD. THU NIGHT INTO FRI...THE GEM AND ECMWF HAVE REMAINED FARTHER SOUTH WITH THE TRACK OF THE CLIPPER SHRTWV COMPARED TO THE NAM AND GFS. EVEN THOUGH THERE IS LINGERING MODEL UNCERTAINTY...THERE SHOULD BE ENOUGH 700-300 MB QVECTOR CONV WITH THIS FEATURE TO SUPPORT AT LEAST LOW END PCPN CHANCES OVER MOST OF THE CWA FRI...ESPECIALLY OVER THE NORTH HALF. ALTHOUGH THERE MAY BE ENOUGH WARM AIR IN THE WARM SECTOR TO SUPPORT SOME LIGHT RAIN...WET-BULB ZERO HEIGHTS FAVOR MAINLY SNOW. HIGHS SHOULD STILL CLIMB ABOVE NORMAL INTO THE MID AND UPPER 30S. FRI NIGHT AND SAT...THE LOW PRESSURE SYSTEM WILL DRAG A COLD FRONT THROUGH UPPER MI WITH 850 MB TEMPS FALLING TO NEAR -14C BY 12Z/SAT AND -20C BY 00Z/SUN. THE MOST FAVORABLE PERIOD FOR SNOW SHOWERS... AIDED BY HEAT/MOISTURE FLUX ACROSS SOME GAPS IN THE ICE COVER AND UPSLOPE FLOW INTO THE HIGHER TERRAIN...WILL BE BETWEEN 06Z-18Z WHEN THE GREATER 850-700 MB MOISTURE AND IS PRESENT. ANY SNOW SHOWERS STILL BE LIGHT...GENERALLY ONLY AN INCH OR TWO AT MOST. TEMPS WILL STRUGGLE TO AROUND 20 NORTH BUT MAY CLIMB TO THE UPPER 20S SOUTH. SUN-TUE...AS THE ARCTIC HIGH SETTLES INTO THE REGION SUN...HIGHS WILL REMAIN IN THE TEENS UNDER MOSTLY SUNNY SKIES AFTER MORNING LOWS AT OR JUST BELOW ZERO. MODEL DIFFERENCES ARE MUCH GREATER BY MON-TUE AS THE ECMWF KEEPS MORE TROUGHING AND COLD AIR OVER THE GREAT LAKES COMPARED TO THE GFS/GEM WHICH KEEPS MOST OF THE PCPN WITH A SHRTWV AND LOW TO THE SOUTH AND WEST OF UPPER MICHIGAN. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING) ISSUED AT 727 PM EDT TUE MAR 11 2014 COLDER AIR CONTINUES TO MOVE INTO THE REGION THIS EVENING WITH STRATOCU DECK IMPACTING THE THREE TAF SITES. KSAW CIGS HOLDING IN MVFR RANGE WHILE KIWD AND KCMX ARE EXPECTED TO DROP INTO MVFR LEVELS BY 3Z. PASSAGE OF A WEAK DISTURBANCE IN THE FLOW ALOFT COMBINED WITH VERY COLD AIR FLOWING OVER SOME GAPS IN THE ICE COVER ON LAKE SUPERIOR TO INITIATE -SHSN. VISIBILITIES TO STAY VFR EXCEPT AT KSAW WHERE THERE WILL BE A PERIOD OF MVFR VISIBILITIES WITH BETTER UPSLOPE FLOW THERE IN NNE WINDS. DRIER AIR BEGINS MOVING INTO THE AREA WEDNESDAY MORNING AND WILL SCATTER OUT THE CLOUDS OVER THE WESTERN TAF SITES BY 12Z AND KSAW BY 15Z...WITH VFR PREVAILING THROUGH THE LATTER HALF OF THE FORECAST. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 403 AM EDT WED MAR 12 2014 COLD AIR SURGING SOUTH ACROSS LAKE SUPERIOR THIS PAST EVENING LED TO A PERIOD OF NORTHERLY GUSTS TO 25-30KTS OVER MUCH OF THE LAKE. THESE WINDS ARE EXPECTED TO QUICKLY DIMINISH TODAY AS AN AREA OF HIGH PRESSURE IN NORTHWEST ONTARIO QUICKLY SHIFTS SOUTHEAST OVER THE UPPER GREAT LAKES REGION. THIS HIGH WILL EXIT THE AREA LATE TONIGHT AND THURSDAY MORNING ALLOWING SOUTHWESTERLY WINDS TO START TO INCREASE AHEAD OF THE NEXT CLIPPER SYSTEM THAT WILL MOVE ACROSS LAKE SUPERIOR THURSDAY NIGHT AND FRIDAY MORNING. SOUTHWEST WINDS MAY INCREASE TO 15-25KTS AHEAD OF THIS LOW...THEN SHIFT TO THE NORTHWEST AT SIMILAR VALUES ON THE BACK SIDE OF THE LOW. HIGH PRESSURE WILL THEN BUILD SOUTH FROM CANADA SATURDAY AFTERNOON INTO SUNDAY AND PRODUCE WEAKENING WINDS. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...SRF LONG TERM...JLB AVIATION...RJT MARINE...SRF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
403 AM EDT WED MAR 12 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 403 AM EDT WED MAR 12 2014 THE COLD FRONT THAT SHIFTED SOUTH ACROSS UPPER MICHIGAN LATE YESTERDAY AFTERNOON AND EVENING PRODUCED SNOW SHOWERS OVER MUCH OF WESTERN AND CENTRAL UPPER MICHIGAN...WITH THE STRONGEST SHOWERS SEEN OVER NORTH CENTRAL UPPER MICHIGAN. THIS WAS DUE TO THE NORTH TO NORTHEAST WINDS PROVIDING TERRAIN ENHANCEMENT TO THE LIGHTER SNOW SHOWERS AND ENDED UP PRODUCING ABOUT AN INCH OF SNOW AT OUR OFFICE THROUGH 2AM. THE INTENSITY HAS REALLY DIMINISHED OVER THE LAST HOUR OR TWO DUE TO THE DRY AIR (ASSOCIATED WITH THE HIGH OVER NORTHWEST ONTARIO) THAT HAS BEEN SURGING SOUTH ACROSS LAKE SUPERIOR ON IR SATELLITE. WITH LIMITED BREAKS IN THE ICE...THE COLD AIR (RAP ANALYZED 900MB TEMPERATURES OF -17C) HAS ONLY BEEN ABLE TO PRODUCE A COUPLE LAKE EFFECT CLOUD STREAMERS OFF THE OPEN AREA NEAR ISLE ROYALE AND THAT IS STRETCHING TOWARDS AREAS SOUTHWEST OF THE PORCUPINE MOUNTAINS. THIS DRYING ABOVE 900MB HAS LED TO SIGNIFICANT ADJUSTMENTS TO THE GOING FORECAST. SINCE THE HIGH WILL CONTINUE TO SLIDE SOUTHEAST OVER THE AREA THROUGH THE DAY TODAY...HAVE TRENDED THE FORECAST TOWARDS A FASTER END TO THE SNOW. WOULD EXPECT THE CLOUDS AND LIGHT SNOW SHOWERS OR FLURRIES TO REMAIN THE LONGEST OVER THE NORTH CENTRAL U.P. WHERE THE NORTHEAST WINDS WILL REMAIN MOST FAVORABLE. LOOKING AT 00Z NAM/GFS SOUNDINGS THEY DO HOLD ONTO MOISTURE RIGHT BELOW THAT INVERSION INTO THE AFTERNOON FOR KSAW...BUT THE LAST SEVERAL RAP RUNS REALLY SCOUR THAT MOISTURE OUT. THUS...WILL KEEP THE TREND TOWARDS PARTLY CLOUDY SKIES BY AFTERNOON OVER THE NORTH CENTRAL AND PARTLY CLOUDY TO MOSTLY SUNNY ELSEWHERE AWAY FROM THE UPSLOPE FLOW. AS FOR THE SNOW SHOWERS...HAVE CUT THAT BACK SIGNIFICANTLY...WITH THEM MAINLY BEING CONFINED TO THE NORTH CENTRAL FOR THE NEXT FEW HOURS AND THEN QUICKLY DIMINISHING DURING THE MORNING WITH THE WINDS STARTING TO BACK MORE TO THE NORTH-NORTHWEST. WILL MONITOR CLOUD/SNOW TRENDS THROUGH DAY BREAK AND MAY NEED TO DIMINISH THEM EVEN EARLIER THAN THE GOING FORECAST. WITH THE COLD AIR ALOFT THAT IS MOVING OVER THE AREA...EXPECT THE EARLY MORNING TEMPERATURES TO CONTINUE TO SLOWLY FALL. THE 3AM OBS (RANGING FROM 9 DEGREES IN COPPER HARBOR AND 27 IN MENOMINEE) WILL LIKELY BE THE WARMEST VALUES FOR THE RESPECTIVE LOCATIONS AND ONLY HAVE HIGHS IN THE UPPER SINGLE DIGITS TO THE NORTH AND THE MID TEENS TO THE SOUTH. AM A LITTLE CONCERNED THE WARM MARCH SUN THIS AFTERNOON COULD PRODUCE HIGHS A LITTLE WARMER THAN EXPECTED AND DID ADJUST INLAND WEST AREAS UP A COUPLE DEGREES TO ACCOUNT FOR THIS. FOR SEVERAL COOP SITES OVER THE WEST THAT REPORT ON A 7AM-7AM CYCLE...DAYTIME HIGHS TODAY COULD BE NEAR OR BREAK RECORD LOW HIGHS FOR THE OBS THAT WILL BE REPORTED ON MARCH 13TH. WITH THE HIGH BEING OVER DIRECTLY OVER THE U.P. THIS EVENING AND CLEAR SKIES...EXPECT TEMPERATURES TO QUICKLY DROP OVER THE WEST AND CENTRAL INITIALLY WITH THE LIGHT WINDS. THOSE AREAS SHOULD SEE THEIR LOWS EARLIER THAN THE EAST DUE TO THE HIGH SHIFTING SOUTHEAST OF THE AREA LATE TONIGHT AND ALLOWING SOUTHERLY FLOW TO DEVELOP. IN ADDITION...MID CLOUDS WILL BE ARRIVING OVER THE WEST LATE IN RESPONSE TO INCREASING WARM AIR ADVECTION ALOFT AND COULD EVEN LEAD TO SOME LIGHT SNOW SHOWERS OVER THE WESTERN QUARTER OF LAKE SUPERIOR BEFORE 12Z. OVER THE EAST...THE LATER WEAKENING OF THE WINDS SHOULDN/T HAVE MUCH AFFECT ON THE LOWS AND EXPECT THE LONGER RADIATIONAL COOLING TIME TO ALLOW LOWS TO EASILY FALL INTO THE TEENS BELOW ZERO. WILL CONTINUE TO FOLLOW THE NH/REGIONAL CANADIAN MODEL FOR TEMPERATURES OVER THE EAST...DUE TO IT/S GREAT PERFORMANCE THIS WINTER ON THESE TYPES OF NIGHTS. DID TREND LOWS DOWN A LITTLE FOR SOME OF THE TRADITIONAL COLD SPOTS (RAWS SITES LIKE DOE LAKE AND SPINCICH LAKE)...WHICH WILL LIKELY SEE VALUES FALLING INTO THE LOWER -20S. CURRENT FORECAST HAS LOWS NEARING/BREAKING RECORDS FOR MANISTIQUE (-7 IN 1948) AND MUNISING (-10 IN 1926). .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 449 PM EDT TUE MAR 11 2014 THE COLDEST PERIOD IN THE NEAR FUTURE WILL BE THURSDAY MORNING...WITH TEMPS BOTTOMING OUT IN THE SINGLE DIGITS BELOW 0F OVER THE W HALF...AND IN THE TEENS BELOW IN THE TRADITIONAL LOW SPOTS OVER THE E HALF. A COUPLE OF SITES DO HAVE WIND CHILLS FALLING TO -20 TO -28F AROUND DAYBREAK THURSDAY. ON A POSITIVE NOTE...WINDS WILL BE VERY RELAXED AS THE SFC HIGH STRETCHING FROM JAMES BAY THROUGH IA AND N TX AS 00Z THURSDAY MOVES OVER LAKE MI AND LOWER BY BY 12Z THURSDAY. WITH THE RETURN OF WAA...DOWNSLOPE SSW WINDS THURSDAY WILL LIKELY BRING TEMPS AT IWD TO RIGHT AROUND 40F...WHILE OUT E THEY WILL STRUGGLE TO GET INTO THE MID 20S. THE SFC LOW ACROSS MUCH OF MANITOBA AT 18Z THURSDAY WILL SHIFT ALONG THE MN/ONTARIO BORDER AROUND 06Z FRIDAY..AND EXIT ACROSS E LAKE SUPERIOR/E UPPER MI AROUND 18Z FRIDAY. LIGHT WARM FRONT PRECIP WILL STILL BE POSSIBLE THURSDAY AHEAD OF THE LOW /IN THE FORM OF SNOW/. THE BEST CHANCE OF MIXED PRECIP WILL LIKELY BE DURING THE DAY FRIDAY OVER S UPPER MI WHEN 850MB TEMPS ARE BEGINNING TO FALL BACK FROM THE 2C READINGS EARLIER IN THE DAY TO AROUND -4 TO -6C. EVEN THEN IT WILL BE LIGHT...AS THE BEST SWATH OF MOISTURE STAYS ON THE N SIDE OF THE LOW...ACROSS LAKE SUPERIOR AND JUST N OF LAKE SUPERIOR IN ONTARIO. SIGNIFICANT DIFFERENCES STILL REMAIN...ALTHOUGH THE TRACK OF THE SFC LOW IS ONLY APPROX 100MI APART FRIDAY OVER THE AREA...INSTEAD OF THE 200MI IT WAS YESTERDAY. THE POSSIBILITY STILL EXISTS FOR SOME LAKE ENHANCED/EFFECT SNOW FRIDAY NIGHT INTO SATURDAY WITH THE GAPS IN THE ICE OVER W LAKE SUPERIOR. OTHERWISE...NO MAJOR CHANGES HAVE BEEN DONE TO THE FCST BEYOND SATURDAY. COLD HIGH PRESSURE WILL BE THE RULE...SINKING OVER THE CWA THROUGH SUNDAY NIGHT. ONLY MINIMAL LES POPS KEPT IN FOR THE COLD N WINDS. BY MONDAY THE HIGH WILL SHIFT E...WITH WARMER AIR SURGING IN MONDAY NIGHT/TUE AHEAD OF THE NEXT LOW FROM S CENTRAL CANADA. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING) ISSUED AT 727 PM EDT TUE MAR 11 2014 COLDER AIR CONTINUES TO MOVE INTO THE REGION THIS EVENING WITH STRATOCU DECK IMPACTING THE THREE TAF SITES. KSAW CIGS HOLDING IN MVFR RANGE WHILE KIWD AND KCMX ARE EXPECTED TO DROP INTO MVFR LEVELS BY 3Z. PASSAGE OF A WEAK DISTURBANCE IN THE FLOW ALOFT COMBINED WITH VERY COLD AIR FLOWING OVER SOME GAPS IN THE ICE COVER ON LAKE SUPERIOR TO INITIATE -SHSN. VISIBILITIES TO STAY VFR EXCEPT AT KSAW WHERE THERE WILL BE A PERIOD OF MVFR VISIBILITIES WITH BETTER UPSLOPE FLOW THERE IN NNE WINDS. DRIER AIR BEGINS MOVING INTO THE AREA WEDNESDAY MORNING AND WILL SCATTER OUT THE CLOUDS OVER THE WESTERN TAF SITES BY 12Z AND KSAW BY 15Z...WITH VFR PREVAILING THROUGH THE LATTER HALF OF THE FORECAST. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 403 AM EDT WED MAR 12 2014 COLD AIR SURGING SOUTH ACROSS LAKE SUPERIOR THIS PAST EVENING LED TO A PERIOD OF NORTHERLY GUSTS TO 25-30KTS OVER MUCH OF THE LAKE. THESE WINDS ARE EXPECTED TO QUICKLY DIMINISH TODAY AS AN AREA OF HIGH PRESSURE IN NORTHWEST ONTARIO QUICKLY SHIFTS SOUTHEAST OVER THE UPPER GREAT LAKES REGION. THIS HIGH WILL EXIT THE AREA LATE TONIGHT AND THURSDAY MORNING ALLOWING SOUTHWESTERLY WINDS TO START TO INCREASE AHEAD OF THE NEXT CLIPPER SYSTEM THAT WILL MOVE ACROSS LAKE SUPERIOR THURSDAY NIGHT AND FRIDAY MORNING. SOUTHWEST WINDS MAY INCREASE TO 15-25KTS AHEAD OF THIS LOW...THEN SHIFT TO THE NORTHWEST AT SIMILAR VALUES ON THE BACK SIDE OF THE LOW. HIGH PRESSURE WILL THEN BUILD SOUTH FROM CANADA SATURDAY AFTERNOON INTO SUNDAY AND PRODUCE WEAKENING WINDS. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...SRF LONG TERM...KF AVIATION...RJT MARINE...SRF
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
353 AM EDT WED MAR 12 2014 .SHORT TERM... TODAY AND TONIGHT A HIGH IMPACT WINTER STORM SYSTEM REMAINS ON TRACK FOR THE SOUTH HALF OF SE MICHIGAN WITH THE PEAK OF THE EVENT DURING THE MORNING COMMUTE ALONG AND SOUTH OF THE I-69 CORRIDOR. THE SYSTEM WILL BRING HEAVY SNOW AND STRONG WIND OVER THE REGION DURING THE MORNING BEFORE DIMINISHING DURING EARLY AFTERNOON. HEADLINE ADJUSTMENTS CONSIST OF A WARNING UPGRADE TO LIVINGSTON, SHIAWASSEE, GENESEE, AND LAPEER. THE CHARACTER OF THIS EVENT CONTINUES TO EXHIBIT A SHARP SNOWFALL GRADIENT ON THE NORTH FLANK TO THE DEGREE THAT THE NORTHERN REACHES OF MIDLAND AND BAY COUNTIES WILL SEE JUST A DUSTING OF ACCUMULATION WHILE LOCATIONS ALONG THE I-69 CORRIDOR COULD SEE 6 INCHES IN 9 HOURS, AND LOCATIONS CLOSE TO THE OHIO BORDER COULD APPROACH 10 INCHES IF MESOSCALE ELEMENTS LINE UP JUST RIGHT. IN ADDITION, STRONG NORTHERLY WIND GUSTS COULD PRODUCE NEAR BLIZZARD CONDITIONS AT TIMES. AIDING IN THE DETERMINATION OF HEADLINE ADJUSTMENTS IS THE 00Z MODEL SUITE COMING IN WITH SOLID AGREEMENT ON THE TRACK OF THE SURFACE LOW DIRECTLY ALONG THE OHIO RIVER TO THE SOUTHWEST PENNSYLVANIA/WEST VIRGINIA BORDER BY NOON. THAT HELPS ADD CONFIDENCE TO THE LOCATION, INTENSITY, AND DURATION OF MESOSCALE FORCING FEATURES TARGETED FOR THE SLIGHT NORTHWARD EXPANSION OF THE WARNING AREA. IT ALSO REINFORCES THE IDEA OF HIGHLIGHTING THE WIND FOR HURON AND SANILAC COUNTIES GIVEN THE SHARP GRADIENT OF MEANINGFUL SNOW ACCUMULATION THERE. SURFACE OBSERVATIONS AND RADAR DEPICTION AROUND THE MIDNIGHT HOUR REVEALED THE TENDENCY FOR A RAPID CHANGE TO ALL SNOW IN REGIONS OF HIGHER PRECIPITATION RATE WITHIN THE LEADING ARM OF MID LEVEL FRONTAL FORCING. AFTER A BRIEF LULL, AND WITH ADDITIONAL LOW LEVEL COLD ADVECTION, IT IS NO SURPRISE THAT THIS REGION OF THE SYSTEM HAS LIT UP AGAIN WITH ALL SNOW AS THE PRIMARY MOISTURE SURGE ARRIVES. A CLOSED CIRCULATION AND TRUE TROWAL STRUCTURE WILL BE ABSENT FROM THE SYSTEM BUT A DEEP AND DYNAMIC DEFORMATION ZONE ON THE NW FLANK OF THE LOW WILL ENSURE A STRONG MESOSCALE RESPONSE TO FORCING AS THE SYSTEM MOVES THROUGH SE MICHIGAN. THE FIRST SIGNS OF THIS PROCESS IS THE RAPID CLOUD TOP COOLING IN IR SATELLITE IMAGERY BETWEEN MIDNIGHT AND 3 AM WITH RADAR COMPOSITE INDICATING A WIDE BAND OF HEAVY PRECIPITATION FROM NORTHERN MISSOURI INTO OUR AREA ALONG THE I-69 CORRIDOR. CONVECTIVE ELEMENTS TO THE SOUTH ARE MORE INDICATIVE OF CONVECTIVE INSTABILITY IN THE FRONTAL ZONE BELOW 850 MB, AND THIS IS WHERE LIGHTNING STRIKES SHOULD REMAIN, BUT SOME THUNDER SNOW WITHIN THE DEFORMATION AXIS IS NOT OUT OF THE QUESTION AS FAR NORTH AS METRO DETROIT. MODEL CROSS SECTIONS INDICATE IMPRESSIVE CONVECTIVE INSTABILITY IN THE 700-500 MB LAYER MATCHING UP WELL WITH THE OBSERVED BAND FILLING IN OVER THE SOUTH HALF OF SE MICHIGAN. THIS, ALONG WITH SPECIFIC HUMIDITY OF 3-4 G/KG WILL MAKE MAXIMUM USE OF A DEEP WEDGE OF FRONTOGENESIS EXCEEDING 100 UNITS. SIMILAR DEPICTION IN THE LATEST RAP OUTPUT INDICATES THE BURST OF HEAVY SNOWFALL RATES FROM HIGHER ALTITUDE AND WITH HIGHER SNOW RATIO PERSISTING THROUGH CENTRAL SECTIONS OF THE REGION WITH A PIVOT OCCURRING IN THE 12-15Z TIME PERIOD BEFORE MIGRATING SOUTHWARD AND EASTWARD DURING THE LATE MORNING. THIS IS THE SUSPECTED SOURCE OF OVERACHIEVEMENT IN SNOWFALL TOTALS ON THE NORTHERN FRINGES OF THE WARNING AREA. FARTHER SOUTH, THE GOING 6 TO 9 INCH FORECAST LOOKS SOLID AS THE MID LEVEL FRONTAL ZONE AND DEFORMATION ZONE FILL IN TO FORM ONE SOLID NW FLANK OF THE SYSTEM WITH 1-2 INCH PER HOUR PEAK RATES FOR LONGER DURATION THAN POINTS NORTH. THE SYSTEM WILL EXIT THE AREA BY MID AFTERNOON WITH TRAILING NORTHERLY FLOW CARRYING IN ANOTHER ROUND OF ARCTIC AIR. DEPENDING ON THE CLEARING TREND, BELOW ZERO MIN TEMPS ARE ON TARGET WITH FRESH SNOW COVER BY SUNRISE THURSDAY. && .LONG TERM...THURSDAY THROUGH TUESDAY A QUICK LOOK AT THE LONGWAVE PATTERN THROUGH THE NEXT WEEK SHOW SPLIT FLOW OVER THE WEST COAST WITH THE TROUGH STILL HOLDING ON OVER THE EASTERN CONUS. THE JET STREAM IS VERY ACTIVE/ENERGETIC...BOTH NORTHERN AND SOUTHERN STREAMS...BUT AT THIS POINT IT LOOKS LIKE THE MAJORITY OF THE PRECIP WILL TRY TO STEER CLEAR OF SOUTHERN MI. THE GOOD NEWS IS THAT WE ARE STILL GETTING SURGES OF SOUTHERLY FLOW EVERY THIRD DAY OR SO...BUT THE BAD NEWS IS THAT THESE WARM UPS INTO THE LOW 40S ARE STRUGGLING TO REACH MID MARCH AVERAGE HIGH TEMPS WHICH ARE IN THE MID 40S. TO SUM IT UP...THE MARCH ROLLER COASTER/WAVE TRAIN WILL CONTINUE FOR THE FORESEEABLE FUTURE. WILL NOW HIT ON A FEW FEATURES OF NOTE IN THE EXTENDED PERIOD. THURSDAY WILL BE A COLD DAY AS THE MID/UPPER LEVEL ARCTIC TROUGH REMAINS IN CONTROL WITH NORTHERN EXTENSION OF A HIGH PRESSURE SYSTEM AT THE SURFACE THAT SLIDE SOUTH BEHIND WEDNESDAYS BIG SYSTEM. NORTHERLY WINDS WILL BACK TO WESTERLY AS HEIGHTS BUILD THROUGH THE DAY BUT WE STILL ONLY GET TO 542DAM AT 500MB BY THURSDAY EVENING SO WE WILL NOT REALIZE THAT INCREASE AT THE SFC DURING DAYLIGHT HOURS. FRIDAY WE FIND OURSELVES IN BETWEEN THE EXITING HIGH AND A CLIPPER TRACKING EASTWARD OVER NORTHERN LAKE SUPERIOR. SW TO NE PRESSURE GRADIENT WILL SET UP GOOD SW FLOW AND WAA. LL JET AT 850MB WILL PEAK AROUND 45 KNOTS DURING THE AFTERNOON ALTHOUGH WE ONLY LOOK TO MIX UP TO AROUND 900MB. SHOULD STILL BE FAIRLY BREEZY OUT IN THE AFTERNOON WITH GUSTS REACHING 20-30 MPH. HIGHS SHOULD REACH INTO THE 40S ONCE AGAIN. THERE IS A SLIGHT CHANCE THAT A FEW RAIN/SNOW SHOWERS COULD POP UP LATE FRIDAY OR OVERNIGHT BUT THERE IS NOT MUCH MOISTURE IN THE COLUMN TO WORK WITH SO WILL CONTINUE TO LEAN TOWARD A DRY FORECAST. THIS CLIPPER WILL PULL A PAIR OF COLD FRONTS THROUGH THE REGION WHICH WILL CAUSE TEMPS TO DROP BOTH SATURDAY AND SUNDAY AS COLDER AND COLDER AIR WORKS INTO THE AREA. SAME HOLDS TRUE FOR SAT/SUN THAT MODELS ARE TRYING TO POP A FEW SHOWERS BUT DOMINATE AREA OF HIGH PRESSURE BUILDING IN FROM CANADA WILL CONTINUE TO KEEP VERY DRY AIR IN PLACE MAKING IT HARD FOR ANYTHING TO DEVELOP. EARLY NEXT WEEK IT LOOKS LIKE THE NORTHERN AND SOUTHERN STREAMS OF THE JETS WILL PHASE AGAIN PRODUCING ANOTHER STRONG LOW PRESSURE SYSTEM. ALL INDICATIONS AT THIS POINT ARE THAT THE STORM WILL DEVELOP MUCH FURTHER SOUTH AND EAST OF MI. && .MARINE... A STRONG LOW PRESSURE SYSTEM WILL DEEPEN AS IT TRACKS ALONG THE OHIO RIVER THROUGH THIS AFTERNOON. THE TRACK OF THE STORM PLACES THE EASTERN GREAT LAKES IN THE TIGHT NORTHEAST TO SOUTHWEST PRESSURE GRADIENT FIELD WHICH WILL RESULT IN GALE FORCE WINDS TODAY. GALE WARNINGS ARE IN EFFECT FOR LAKE HURON...LAKE ERIE AND LAKE ST CLAIR THROUGH THIS EVENING. SEE CURRENT MARINE HEADLINES FOR THE LATEST INFORMATION. A HIGH PRESSURE SYSTEM WILL THEN DROP THROUGH THE GREAT LAKES FROM CANADA ALLOWING THE WINDS TO SUBSIDE. YET ANOTHER LOW PRESSURE SYSTEM WILL MOVE ACROSS NORTHERN LAKE SUPERIOR ON FRIDAY BRING A RETURN OF MODERATE SOUTHWEST FLOW AND MILDER AIR. && .AVIATION...ISSUED 1159 PM EDT TUE MAR 11 2014 //DISCUSSION... CONDITIONS ARE SLOWLY GOING DOWN TO MVFR AS THE FIRST BATCH OF LIGHT RAIN EXITS THE REGION. CONDITIONS WILL CONTINUE TO DETERIORATE WITH THE ONSET OF STEADIER SNOW AFTER MIDNIGHT WITH HEAVY SNOWFALL RATES LIKELY TO BRING IFR TO LIFR CONDITIONS TO KPTK AND POINTS SOUTH BETWEEN ROUGHLY 09Z AND 15Z. NORTHERLY WINDS WILL GUST TO 30 KNOTS OR HIGHER DURING THE DAY ON WEDNESDAY WHICH WILL ADD THE COMPLICATING FACTOR OF BLOWING SNOW WHICH MAY CONTINUE TO IMPEDE VISIBILITY EVEN AS SNOW WINDS DOWN MIDDAY WEDNESDAY. FOR DTW...RAPIDLY DETERIORATING CONDITIONS CAN THEN BE EXPECTED WITH VISIBILITIES FALLING TO 1/4 MILE OR LESS BETWEEN 09Z AND 15Z. ONCE STEADY SNOW BEGINS AFTER MIDNIGHT...PTYPE WILL REMAIN ALL SNOW THROUGH THE EVENT. ACCUMULATIONS OF 6 TO 8 INCHES CAN BE EXPECTED...THE BULK OF WHICH WILL ACCUMULATE DURING THE AFOREMENTIONED PEAK PERIOD. THE PREDOMINANTLY NORTHERLY WIND DIRECTION IS EXPECTED TO LIMIT CROSSWIND CONCERNS. //DTW THRESHOLD THREATS... * HIGH CONFIDENCE ON CEILING BELOW 5000 FEET TONIGHT AND WEDNESDAY. * HIGH CONFIDENCE IN PTYPE OF SNOW AFTER 08Z && .DTX WATCHES/WARNINGS/ADVISORIES... MI...WINTER STORM WARNING...MIZ060-MIZ061-MIZ062-MIZ063-MIZ068-MIZ069- MIZ070-MIZ075-MIZ076-MIZ082-MIZ083...UNTIL 3 PM WEDNESDAY. WINTER WEATHER ADVISORY...MIZ053-MIZ054-MIZ055...UNTIL 3 PM WEDNESDAY. WIND ADVISORY...MIZ049-MIZ055...FROM 8 AM WEDNESDAY TO 6 PM WEDNESDAY. LAKE HURON... GALE WARNING...LHZ363-LHZ421-LHZ422-LHZ441-LHZ442-LHZ443-LHZ462- LHZ463-LHZ464...UNTIL 8 PM WEDNESDAY. LAKE ST CLAIR... GALE WARNING...FROM 8 AM WEDNESDAY TO 8 PM WEDNESDAY. MI WATERS OF LAKE ERIE... GALE WARNING...FROM 8 AM WEDNESDAY TO 8 PM WEDNESDAY. && $$ SHORT TERM...BT LONG TERM....DRK MARINE.......DRK AVIATION.....KURIMSKI YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1157 PM CDT TUE MAR 11 2014 .UPDATE... ISSUED AT 1157 PM CDT TUE MAR 11 2014 LATEST SURFACE MAP SHOWS A BACKDOOR COLD FRONT STRETCHED FROM SOUTHEAST SASKATCHEWAN SOUTHEAST INTO WESTHOPE...DRAKE...AND ELLENDALE. COLDER AIR TO THE EAST OF THIS FRONT WITH ISOLATED SNOWSHOWERS IN THE NORTHERN PORTION OF THE JAMES RIVER VALLEY WILL WANE OVERNIGHT AS VERTICAL MOTION ENDS AND SHIFT EAST. PATCHY FOG POSSIBLE ALONG/NEAR THE FRONTAL BOUNDARY OVERNIGHT SO WILL KEEP SOME MENTION OF THIS IN THE FORECAST. LATEST FOG/STRATUS LOOP OUTLINES THE SURFACE COLD FRONT WELL WITH OVERCAST CONDITIONS ALONG AND EAST OF THE FRONT. WITH NORTHWEST UPPER FLOW PARALLELING THE SURFACE COLD FRONT...THE FRONT WILL STALL OUT OVERNIGHT IN ITS CURRENT POSITION AND THEN BEGIN TO MOVE EAST WEDNESDAY IN THE FORM OF A WARM FRONT. VERTICAL MOTION INDUCED WITH WARM AIR ADVECTION IN THE 850MB TO 700MB LAYER PER TIME HEIGHT CROSS SECTIONS WILL BE FAVORABLE FOR SCT TO BKN CLOUDS WEDNESDAY...BUT DRY CONDITIONS PREVAIL. THE MAIN FORECAST ELEMENTS HARE IN GOOD SHAPE WITH LITTLE OR NO UPDATES PLANNED AT THIS TIME. UPDATE ISSUED AT 1014 PM CDT TUE MAR 11 2014 ONLY A FEW MINOR UPDATES TO THE LATE EVENING FORECAST. AREA OF LOW VFR-MVFR CLOUDS CONTINUES TO DROP SOUTHEAST FROM CANADA INTO THE SOURIS RIVER VALLEY AND DEVILS LAKE BASIN. THIS IS FORECAST TO DROP SOUTHEAST INTO THE JAMES RIVER VALLEY LATE TONIGHT. A FEW WANING SHOWERS IN THE FAR SOUTH CENTRAL OTHERWISE MOSTLY CLEAR ALONG AND WEST OF THE HIGHWAY 83 CORRIDOR. WITH THE LATE EVENING UPDATED WE TRIMMED THE WESTERN EXTENT OF SNOW DROPPING SOUTH FROM CANADA...KEEPING IT CONFINED TO ONLY EASTERN PORTIONS OF CENTRAL NORTH DAKOTA. WILL HAVE TO KEEP AN EYE ON TEMPERATURES IN THE WEST AS SKIES HAVE CLEARED...BUT DEW POINT TEMPERATURES REMAIN IN THE MID 20S. LOWERED MINS IN THE FAR SOUTHWEST A COUPLE DEGREES. UPDATE ISSUED AT 727 PM CDT TUE MAR 11 2014 A WEAK INVERTED TROUGH REMAINS OVER CENTRAL NORTH DAKOTA WITH HIGH PRESSURE SITUATED TO THE WEST AND EAST OF THE TROUGH. ISOLATED DIURNAL CONVECTION OVER THE WEST CENTRAL AND SOUTHWEST WILL CONTINUE TO DIMINISH EARLY THIS EVENING. DID EXTEND ISOLATED SHOWERS INTO THE EARLY EVENING HOURS. TO THE EAST...VERY LIGHT REFLECTIVITIES IN SOUTHWEST MANITOBA WILL MOVE INTO THE FAR NORTHEAST CWA WITHING THE NEXT HOUR. OTHERWISE LITTLE IN THE WAY OF PRECIPITATION NOTED. WILL TREND LOWER ON POPS THIS EVENING OVER THE NORTHEAST CWA. LATEST 22Z HRRR AND 23Z RAP INDICATE MORE WIDESPREAD REFLECTIVITIES MID TO LATE EVENING. UPDATE ISSUED AT 518 PM CDT TUE MAR 11 2014 QUICK UPDATE TO ADD SOME LATE AFTERNOON SHOWERS ACROSS THE WEST. AN AREA OF CONVECTIVE SHOWERS HAD DEVELOPED FROM AROUND WILLISTON SOUTH THROUGH DICKINSON TO BOWMAN AND HETTINGER. THESE SHOULD DISSIPATE QUICKLY EARLY THIS EVENING. TEXT PRODUCTS HAVE BEEN SENT. && .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 339 PM CDT TUE MAR 11 2014 THE MAIN FORECAST ISSUE CONCERNING THE WEATHER IS TEMPS TONIGHT/WEDNESDAY AND LIGHT SNOW POTENTIAL EAST TONIGHT. OPERATIONALLY...THE MAIN CONCERN WILL CONTINUE TO BE THE ONGOING FLOODING FROM SNOW MELT AND ISOLATED ICE JAMES. SEE HYDRO DISCUSSION BELOW FOR ADDITIONAL DETAILS. FOR TONIGHT...THERE IS GOOD MODEL CONSENSUS TO SUPPORT LIGHT SNOW ALONG THE EASTERN FRINGE OF THE FORECAST AREA...FROM THE TURTLE MOUNTAINS THROUGH THE JAMES RIVER VALLEY. WPC QPF AND SNOW RATIOS AROUND 15:1 INDICATE SNOWFALL AMOUNTS AROUND AN INCH OR SO. THE FAMILIAR RECENT TEMPERATURE PATTERN IS EXPECTED TO CONTINUE OVERNIGHT AND WEDNESDAY...WARMER SOUTHWEST WITH NO SNOW COVER...COLDER NORTH AND EAST WITH LINGERING SNOW PACK. HAVE LEANED TOWARD THE BIAS-CORRECTED GUIDANCE WHICH IS DOING A BETTER JOB HANDLING THE SNOW COVER VARIATIONS. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 339 PM CDT TUE MAR 11 2014 ABOVE NORMAL TEMPERATURES WILL HIGHLIGHT THE MAJORITY OF THE EXTENDED FORECAST. THE 12 UTC DETERMINISTIC AND ENSEMBLE SUITE IS IN GOOD AGREEMENT ON A BROAD UPPER LEVEL RIDGE ACROSS THE WESTERN AND CENTRAL CONUS WEDNESDAY AND THURSDAY...WITH A BRIEF BREAK DOWN FRIDAY INTO SATURDAY...BEFORE THE RIDGE BUILDS AGAIN SUNDAY INTO NEXT WEEK. THIS SUPPORTS A GENERALLY DRY OVERALL PATTERN WITH ABOVE NORMAL TEMPERATURES...FOLLOWING THE WARMER EDGE OF GUIDANCE WHICH HAS VERIFIED BEST WITH THE PATTERN CHANGE TO MILDER WEATHER AND THE LOSS OF SNOW. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT) ISSUED AT 1157 PM CDT TUE MAR 11 2014 MVFR TO LOW VFR CIGS ACROSS KJMS WILL CONTINUE UNTIL 17Z WEDNESDAY. ISOLATED SNOW SHOWERS WILL REMAIN A THREAT AT KJMS UNTIL 09Z WEDNESDAY BEFORE ENDING. THE CURRENT SATELLITE IMAGERY AND RELATIVE HUMIDITY FOREACST SUGGESTS THAT KMOT AND KBIS WILL REMAIN JUST FAR ENOUGH WEST OF THE MVFR CIGS OVERNIGHT...BUT WILL MONITOR AND ADJUST IF THIS CHANGES. KDIK/KISN WILL REMAIN VFR THROUGH THE OVERNIGHT WITH ALL TERMINALS IN VFR STATUS WEDNESDAY INTO WENDESDAY NIGHT. && .HYDROLOGY... ISSUED AT 339 PM CDT TUE MAR 11 2014 MULTIPLE FLOOD HEADLINES REMAIN IN EFFECT ACROSS THE MISSOURI BASIN. WET...DEEPLY FROZEN SOILS HAVE LEAD TO VERY HIGH RUNOFF RATES OF THE MINIMAL SNOWPACK INTO THE AREA RIVERS AND STREAMS...RESULTING IN ICE BREAK UP AND JAMS. A FLOOD WATCH HAS BEEN ISSUED FOR THE HEART RIVER NEAR MANDAN THROUGH FRIDAY EVENING. AS FLOWS INCREASE AND ICE FROM UPSTREAM MAKES ITS WAY INTO THE AREA...THE RISK OF ICE JAMS NEAR MANDAN WILL INCREASE. THE MISSOURI NEAR WILLISTON AT THIS TIME IS FORECAST TO RISE TO NEAR 21.5 FEET WEDNESDAY NIGHT...SHY OF THE 22 FT FLOOD STAGE. HOWEVER...THIS WILL HAVE TO BE CLOSELY MONITORED AS BROKEN ICE IN THE SIDNEY AND FAIRVIEW STRETCHES OF THE YELLOWSTONE RIVER ARE TRANSPORTED INTO THE WILLISTON AREA. WIDESPREAD RUNOFF...RIVER AND STREAM RISES AND ICE JAM POTENTIAL WILL INCREASE ACROSS THE SOURIS AND JAMES BASINS THROUGH THE END OF THE WEEK AS MILDER WEATHER RETURNS TO THE AREA ONCE AGAIN. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...KS SHORT TERM...RK LONG TERM...AYD AVIATION...KS HYDROLOGY...AYD
AREA FORECAST DISCUSSION
NWS NORMAN OK
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
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
601 AM EDT WED MAR 12 2014 .SYNOPSIS... A STRONG LATE-WINTER STORM WILL IMPACT THE AREA TODAY...FOLLOWED BY COLD AND BLUSTERY CONDITIONS WITH WELL-BELOW NORMAL TEMPERATURES FOR THURSDAY. TEMPERATURES WILL REBOUND TO NEAR SEASONAL LEVELS FRIDAY INTO THE WEEKEND...AHEAD OF A FRONTAL SYSTEM PUSHING SOUTHEAST FROM THE GREAT LAKES. THIS FRONT MAY PRODUCE SOME RAIN OR SNOW SHOWERS ON SATURDAY. && .NEAR TERM /THROUGH TONIGHT/... LOTS OF ACTION THIS PERIOD WITH RAIN ALREADY STRAFING THE NRN BORDER. MORE RADAR RETURN OVER CENTRAL OH ARE MOVING QUICKLY THIS WAY. THE FRONTAL BOUNDARY IS LAID OUT FROM PHL ALONG THE MASON- DIXON LINE TO KDAY AND KIND. SFC LOW IS CONSOLIDATING OVER THE WABASH AND IS ABOUT 995MB AT 08Z. GUSTS ON THE BACKSIDE OF THE LOW ARE ALREADY INTO THE 20S AND 30S. STRONG WARM ADVECTION OVER THE STATE IS KEEPING TEMPS IN THE 40S...EXCEPT ALONG THE NY BORDER WITH 30S NUDGING IN ON LIGHT N/NE WIND. DEWPOINTS HAVE RISEN SLIGHTLY AND ARE GENERALLY IN THE 30S. WET BULBS IN THE NRN MTS WILL STILL LIKELY YIELD RAIN AT FIRST...BUT NAM/RUC PROFILES DO MAKE IT MAINLY ISOTHERMAL FOR THE LOWEST FEW KFT THIS MORNING. THUS...IT COULD BE ANYTHING FOR THE FIRST FEW HOURS. THEN...IT GETS COLD AS PRECIP INTENSITY SHOULD PICK UP LATER THIS MORNING. COUPLED JET STRUCTURE STILL LOOKING LIKE A CLASSIC EXAMPLE...AND INTERACTION SHOULD DROP THE PRESSURE OF THE MAIN SFC LOW AS IT TRAVERSES THE PA TURNPIKE THROUGH THE LATE MORNING AND INTO THE EVENING. IT WILL TAKE IT/S OWN TOLL BY BRINGING MODERATE TO HEAVY RAIN TO MOST OF THE STATE TODAY...BUT RUC POINTS TO A LOWERING OF THE LI/S AND TRUE INSTABILITY ACROSS THE SRN THIRD/HALF OF THE AREA LATE THIS AFTN AND EARLY THIS EVENING. SPC HAS A SLIGHT RISK AREA COVERING THAT ROUGH AREA...AND HAVE ADDED GUSTY WIND WORDING TO THE GRIDS FOR THAT TIME FRAME - RIGHT AS THE LOW PASSES OVERHEAD. THE SNOW WILL BE HEAVIEST IN THE N IN THE MID DAY AND AFTERNOON. QPF IS IMPRESSIVE BUT MAY BE TAINTED BY CONVECTIVE FEEDBACK ON SOME MDL SOLUTIONS. STILL...THE OVERALL PICTURE OF 1-1.25 INCHES N AND 0.5-0.75 S IS LOOKING GOOD. THUS...WITH THE BULK OF THE PRECIP FALLING AS SNOW ALONG THE NY BORDER...ESP WARREN AND MCKEAN COS...THE GOING STORM TOTALS LOOK SOLID WITH 8-10 THERE. THE SNOW ACCUMULATION GRADIENT WILL BE TIGHT - ESP DURING THE DAYTIME - WITH ALMOST NO SNOW SOUTH OF ROUTE 6 IN THE MORNING AND NOT FAR S OF THE NRN TIER OF COS THIS AFTERNOON...DESPITE FALLING TEMPS. THE WARM AIR ALOFT IS JUST TOO MUCH AND SUN ANGLE NOW HIGH ENOUGH TO MAKE THE SNOW FORECAST A REAL TROUBLE. AS THE TEMPS GET COLD THIS AFTERNOON/EVENING...THERE IS A DANGER OF THE RAIN-WET ROADS BECOMING ICY QUICKLY AS THE PRECIP TYPE CHANGE OVER OCCURS FROM N TO S. THE SFC LOW SHOULD CONTINUE TO DEEPEN AS IT MOVES INTO NJ THIS EVENING. THE PRECIP SHOULD TAPER RATHER ABRUPTLY IN THE CENTRAL AND SERN ZONES THIS EVENING. BY 01Z...LITTLE IF ANY PRECIP IS LEFT THERE. SO BY THE TIME THE PROFILES GET COLD ENOUGH FOR SNOW THERE...IT SHOULD BE ENDING. WILL KEEP ALL SNOW TOTALS AND TIMING AS IS WITH JUST MINOR EDITING. THE WINDS WILL GET STRONG/GUSTY IN THE NORTHERN MTS LATE THIS MORNING...BUT THE PASSAGE OF THE LOW AND ANY STORMS IN THE SOUTH WILL KICK THEM UP THERE IN THE EARLY EVENING. && .SHORT TERM /THURSDAY/... THE SNOW SHOULD BE TAPERING OFF TO SCT SHSN IN THE EVENING ACROSS THE NRN AND WRN MTS...BUT WILL KEEP CURRENT TIMING ON WSW FLAGS TO ALLOW FOR LINGERING SNOW AND BLOWING SNOW PROBLEMS. LOW PRESSURE CONTINUES TO DEEPEN AS IT MOVES AWAY AND CREATES WIND PROBLEMS FOR THE LOCAL AREA. THE WINDS WILL GET FASTER ACROSS THE SRN HALF OF THE AREA TONIGHT AND SUSTAINED SPEEDS AND GUSTS MAY BOTH REACH WIND ADVY CRITERIA. HAVE THUS POSTED AN ADVY FOR THOSE AREAS THROUGH THURSDAY NOON. WHILE WINDS WILL BE STRONGEST THERE IN THE SOUTH...THE TEMPS DO NOT DROP FAST ENOUGH TO GET WIND CHILLS BELOW ADVY THE LINE OF -15F. WILL ISSUE AN ADVY FOR THE NW HALF AS THE CRITERIA SHOULD EASILY BE MET. IF THE TIMING OF THE SNOW WERE TO BE ENDING LATER THURS MORNING...WE MAY HAVE BEEN ABLE TO FORGO A WIND CHILL ADVY AND JUST WRAP IT INTO THE WSW. BUT THE CHILLS WILL LAST MUCH LONGER THAN THE ACCUMULATING SNOW...THROUGH THE ENTIRE MORNING...WHEREAS THE SNOW SHOULD BE VIRTUALLY DONE BY 2 AM/06Z. THURSDAY SHOULD BE ONE OF THE COLDEST WE HAVE SEEN YET THIS WINTER. THIS IS EVEN MORE IMPRESSIVE GIVEN THE MID-MARCH TIMING. 8H TEMPS DROP INTO THE MINUS 20S C IN THE MORNING...BUT THIS NASTINESS GETS DRAGGED THROUGH THE AREA RATHER QUICKLY DUE TO THE SHARPNESS OF THE TROUGH AND PROGRESSIVE NATURE OF THE FLOW ALOFT. LITTLE BREAKS IN THE CLOUDS OVER THE S/SE OVERNIGHT SHOULD LEAD TO GREATER BREAKS IN THE MORNING OVER THE SRN TIER AND SERN AREAS COULD CLEAR UP TOTALLY BY THE END OF THE MORNING. WILL PLAY IT MORE-CLOUDY THAN THAT FOR NOW. EVEN WITH THE SUN AND DOWNSLOPE...THE MAXES IN THE SE WILL ONLY BE IN THE M/U20S. THAT WOULD BE WELCOME IN THE NRN TIER WHERE MAXES MAY NOT MAKE IT INTO THE TWEENS /10-12F/. THE GUSTY WINDS WILL GRADUALLY SUBSIDE DURING THE DAY THURS WITH DAYTIME HIGHS 25-30F BELOW NORMAL. DAILY RECORD LOW/MINI-MAXES ARE IN JEOPARDY. IN ADDITION...LOW TEMPS THURS MORNING ACRS WRN PA WILL ALSO BE NEAR DAILY RECORD. SUFFICE IT TO SAY...IT MAY NOT BE THIS COLD AGAIN /ESPECIALLY DURING THE DAYLIGHT HOURS/ UNTIL NEXT WINTER. && .LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/... THE GOOD NEWS IS THAT THE COLD BLAST WILL BE SHORT-LIVED...WITH A RAPID MODERATION OCCURRING ON FRIDAY. BREEZY SW RETURN FLOW IN ADVANCE OF NRN CLIPPER SFC LOW TRACKING ACRS THE UPPER GREAT LAKES AND DOWNSLOPING SHOULD HELP TO BOOST TEMPS INTO THE 40S NORTH AND 50S SOUTH. THE MODELS TURN THE LOW TO THE NORTHEAST UP THE ST. LAWRENCE VLY ON DAY 5/SAT...DRAGGING A TRAILING/WEAK COLD FRONT ACRS THE NORTHEAST AND MID-ATL STATES. MODEL CONSENSUS INDICATES SOME LGT PCPN IS POSSIBLE WITH CHC POPS AS THE FRONT SHIFTS SEWD ACRS THE CWA. GEFS/EC ENSEMBLE MEANS SHOW THE LARGE SCALE PATTERN REVERTING BACK TO A WRN RIDGE/ERN TROUGH CONFIGURATION INTO EARLY NEXT WEEK. THIS HAS BEEN THE FAVORED/PREVAILING FLOW REGIME THIS WINTER...WITH A COLD POLAR VORTEX OVER EASTERN CANADA. A STRONG SFC HIGH PUSHING SEWD FROM THE UPPER MS VLY SHOULD DIRECT COLDER AIR INTO THE REGION BEHIND A REINFORCING FROPA ON SUNDAY...WITH TEMPS LKLY TRENDING LOWER BY DAY 7/MON. THE NON-NCEP OPRNL MODELS /12Z CMC AND ECMWF/ ARE MORE BULLISH ON CYCLOGENESIS INVOF THE GULF STREAM JUST EAST OF THE CAROLINAS...WITH THE NW EDGE OF POTNL PCPN SHIELD POSSIBLY REACHING SRN/SERN PA ON ST. PATRICK`S DAY. CONFIDENCE IS LOW GIVEN THE LARGE SPREAD BTWN THE GFS AND ECMWF/CMC. SOMETHING TO MONITOR IN THE DAYS TO COME. && .AVIATION /10Z WEDNESDAY THROUGH SUNDAY/... CIGS COMING DOWN ACROSS THE NW...BFD AREA. 09Z TAFS SENT. EARLIER DISCUSSION BELOW. AS NOTED BELOW...VFR CONDITIONS WILL PREVAIL FOR A WHILE LONGER...MAIN AREA OF RAIN NORTH PA BORDER. 06Z TAFS SENT. EARLIER DISCUSSION BELOW. VFR CONDITIONS WILL CONTINUE THROUGH THE FIRST HALF OF THE OVERNIGHT PERIOD. SAT SHOWS LOW TO MID CLOUDS STREAMING THROUGH WITH CEILINGS AT MOST TAF SITES. THESE WILL SLOWLY LOWER AS THE NIGHT CONTINUES AND RESTRICTIONS WILL ARRIVE AS LIGHT RAIN /AND POSS SNOW NORTH/ AROUND 06Z IN THE NW...AND HEAVIER AREA OF PRECIP ARRIVING STARTING AROUND 12Z WED. BULK OF HEAVIER PRECIPITATION WILL BE BETWEEN LATE WED MORNING AND EARLY WEDNESDAY EVENING. WIDESPREAD ADVERSE CONDITIONS ON WED...WITH RAIN ACROSS MUCH OF THE AREA...SNOW ACROSS THE FAR NORTH...AND SOME RISK OF STRONG TSTMS NEAR THE MD BORDER. BY AFTERNOON...STRONG WIND FIELDS WILL BRING INCREASING NORTHERLY FLOW...LLWS...AND GUSTY WINDS UP TO 40 MPH. THESE CONTINUE THROUGH THE FIRST HALF OF THU AS VERY COLD AIR STAMPEDES INTO PA. WITH STRONG STORM DYNAMICS...CONCERN EXISTS FOR A BURST OF HEAVY WET CONVECTIVE SNOW /AND POSS THUNDER/ NEAR THE CENTER OF THE LOW WED/WED NIGHT. HAVE UPDATED TAFS WITH LLWS AT ALL CENTRAL AND WESTERN TAF SITES FROM 16Z TO AROUND 22Z. OUTLOOK... WED...WIDESPREAD MVFR- IFR RESTRICTIONS IN RAIN AND SNOW. STRONG N/NW WINDS DEVELOPING. LLWS. THU...STRONG/GUSTY N/NW WINDS...GRADUALLY DIMINISHING IN THE AFTERNOON. FRI-SUN...NO SIG WX EXPECTED. && .HYDROLOGY... WITH WARMER TEMPERATURES RAINFALL TODAY...WE EXPECT MODERATE RISES ON RIVERS AND STREAMS. THERE IS STILL ENOUGH ICE IN SPOTS TO LEAD TO ICE JAMS...THOUGH SIGNIFICANT DECAY HAS OCCURRED AT MANY LOCATIONS DUE TO THE RECENTLY WARM WEATHER. ANY ICE JAMS WILL BE ISOLATED IN NATURE. MONITOR WATER LEVELS CLOSELY FOR THE REST OF THE WEEK. && .CTP WATCHES/WARNINGS/ADVISORIES... WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO NOON EDT THURSDAY FOR PAZ004>006-010>012-017-018-024-033-037-041-042. WINTER WEATHER ADVISORY FROM 3 PM THIS AFTERNOON TO 8 AM EDT THURSDAY FOR PAZ017-024-033. WIND ADVISORY FROM 5 PM THIS AFTERNOON TO NOON EDT THURSDAY FOR PAZ025>028-034>036-056>059-063>066. WINTER WEATHER ADVISORY UNTIL 8 AM EDT THURSDAY FOR PAZ006-010- 011-037. WINTER STORM WARNING UNTIL 8 AM EDT THURSDAY FOR PAZ004-005. && $$ SYNOPSIS...DANGELO/LA CORTE NEAR TERM...DANGELO SHORT TERM...DANGELO LONG TERM...STEINBUGL AVIATION...CERU/MARTIN/RXR HYDROLOGY...CR
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
425 AM EDT WED MAR 12 2014 .SYNOPSIS... A STRONG LATE-WINTER STORM WILL IMPACT THE AREA TODAY...FOLLOWED BY COLD AND BLUSTERY CONDITIONS WITH WELL-BELOW NORMAL TEMPERATURES FOR THURSDAY. TEMPERATURES WILL REBOUND TO NEAR SEASONAL LEVELS FRIDAY INTO THE WEEKEND...AHEAD OF A FRONTAL SYSTEM PUSHING SOUTHEAST FROM THE GREAT LAKES. THIS FRONT MAY PRODUCE SOME RAIN OR SNOW SHOWERS ON SATURDAY. && .NEAR TERM /THROUGH TODAY/... LOTS OF ACTION THIS PERIOD WITH RAIN ALREADY STRAFING THE NRN BORDER. MORE RADAR RETURN OVER CENTRAL OH ARE MOVING QUICKLY THIS WAY. THE FRONTAL BOUNDARY IS LAID OUT FROM PHL ALONG THE MASON- DIXON LINE TO KDAY AND KIND. SFC LOW IS CONSOLIDATING OVER THE WABASH AND IS ABOUT 995MB AT 08Z. GUSTS ON THE BACKSIDE OF THE LOW ARE ALREADY INTO THE 20S AND 30S. STRONG WARM ADVECTION OVER THE STATE IS KEEPING TEMPS IN THE 40S...EXCEPT ALONG THE NY BORDER WITH 30S NUDGING IN ON LIGHT N/NE WIND. DEWPOINTS HAVE RISEN SLIGHTLY AND ARE GENERALLY IN THE 30S. WET BULBS IN THE NRN MTS WILL STILL LIKELY YIELD RAIN AT FIRST...BUT NAM/RUC PROFILES DO MAKE IT MAINLY ISOTHERMAL FOR THE LOWEST FEW KFT THIS MORNING. THUS...IT COULD BE ANYTHING FOR THE FIRST FEW HOURS. THEN...IT GETS COLD AS PRECIP INTENSITY SHOULD PICK UP LATER THIS MORNING. COUPLED JET STRUCTURE STILL LOOKING LIKE A CLASSIC EXAMPLE...AND INTERACTION SHOULD DROP THE PRESSURE OF THE MAIN SFC LOW AS IT TRAVERSES THE PA TURNPIKE THROUGH THE LATE MORNING AND INTO THE EVENING. IT WILL TAKE IT/S OWN TOLL BY BRINGING MODERATE TO HEAVY RAIN TO MOST OF THE STATE TODAY...BUT RUC POINTS TO A LOWERING OF THE LI/S AND TRUE INSTABILITY ACROSS THE SRN THIRD/HALF OF THE AREA LATE THIS AFTN AND EARLY THIS EVENING. SPC HAS A SLIGHT RISK AREA COVERING THAT ROUGH AREA...AND HAVE ADDED GUSTY WIND WORDING TO THE GRIDS FOR THAT TIME FRAME - RIGHT AS THE LOW PASSES OVERHEAD. THE SNOW WILL BE HEAVIEST IN THE N IN THE MID DAY AND AFTERNOON. QPF IS IMPRESSIVE BUT MAY BE TAINTED BY CONVECTIVE FEEDBACK ON SOME MDL SOLUTIONS. STILL...THE OVERALL PICTURE OF 1-1.25 INCHES N AND 0.5-0.75 S IS LOOKING GOOD. THUS...WITH THE BULK OF THE PRECIP FALLING AS SNOW ALONG THE NY BORDER...ESP WARREN AND MCKEAN COS...THE GOING STORM TOTALS LOOK SOLID WITH 8-10 THERE. THE SNOW ACCUMULATION GRADIENT WILL BE TIGHT - ESP DURING THE DAYTIME - WITH ALMOST NO SNOW SOUTH OF ROUTE 6 IN THE MORNING AND NOT FAR S OF THE NRN TIER OF COS THIS AFTERNOON...DESPITE FALLING TEMPS. THE WARM AIR ALOFT IS JUST TOO MUCH AND SUN ANGLE NOW HIGH ENOUGH TO MAKE THE SNOW FORECAST A REAL TROUBLE. AS THE TEMPS GET COLD THIS AFTERNOON/EVENING...THERE IS A DANGER OF THE RAIN-WET ROADS BECOMING ICY QUICKLY AS THE PRECIP TYPE CHANGE OVER OCCURS FROM N TO S. THE SFC LOW SHOULD CONTINUE TO DEEPEN AS IT MOVES INTO NJ THIS EVENING. THE PRECIP SHOULD TAPER RATHER ABRUPTLY IN THE CENTRAL AND SERN ZONES THIS EVENING. BY 01Z...LITTLE IF ANY PRECIP IS LEFT THERE. SO BY THE TIME THE PROFILES GET COLD ENOUGH FOR SNOW THERE...IT SHOULD BE ENDING. WILL KEEP ALL SNOW TOTALS AND TIMING AS IS WITH JUST MINOR EDITING. THE WINDS WILL GET STRONG/GUSTY IN THE NORTHERN MTS LATE THIS MORNING...BUT THE PASSAGE OF THE LOW AND ANY STORMS IN THE SOUTH WILL KICK THEM UP THERE IN THE EARLY EVENING. && .SHORT TERM /TONIGHT THROUGH 6 PM THURSDAY/... THE SNOW SHOULD BE TAPERING OFF TO SCT SHSN IN THE EVENING ACROSS THE NRN AND WRN MTS...BUT WILL KEEP CURRENT TIMING ON WSW FLAGS TO ALLOW FOR LINGERING SNOW AND BLOWING SNOW PROBLEMS. LOW PRESSURE CONTINUES TO DEEPEN AS IT MOVES AWAY AND CREATES WIND PROBLEMS FOR THE LOCAL AREA. THE WINDS WILL GET FASTER ACROSS THE SRN HALF OF THE AREA TONIGHT AND SUSTAINED SPEEDS AND GUSTS MAY BOTH REACH WIND ADVY CRITERIA. HAVE THUS POSTED AN ADVY FOR THOSE AREAS THROUGH THURSDAY NOON. WHILE WINDS WILL BE STRONGEST THERE IN THE SOUTH...THE TEMPS DO NOT DROP FAST ENOUGH TO GET WIND CHILLS BELOW ADVY THE LINE OF -15F. WILL ISSUE AN ADVY FOR THE NW HALF AS THE CRITERIA SHOULD EASILY BE MET. IF THE TIMING OF THE SNOW WERE TO BE ENDING LATER THURS MORNING...WE MAY HAVE BEEN ABLE TO FORGO A WIND CHILL ADVY AND JUST WRAP IT INTO THE WSW. BUT THE CHILLS WILL LAST MUCH LONGER THAN THE ACCUMULATING SNOW...THROUGH THE ENTIRE MORNING...WHEREAS THE SNOW SHOULD BE VIRTUALLY DONE BY 2 AM/06Z. THURSDAY SHOULD BE ONE OF THE COLDEST WE HAVE SEEN YET THIS WINTER. THIS IS EVEN MORE IMPRESSIVE GIVEN THE MID-MARCH TIMING. 8H TEMPS DROP INTO THE MINUS 20S C IN THE MORNING...BUT THIS NASTINESS GETS DRAGGED THROUGH THE AREA RATHER QUICKLY DUE TO THE SHARPNESS OF THE TROUGH AND PROGRESSIVE NATURE OF THE FLOW ALOFT. LITTLE BREAKS IN THE CLOUDS OVER THE S/SE OVERNIGHT SHOULD LEAD TO GREATER BREAKS IN THE MORNING OVER THE SRN TIER AND SERN AREAS COULD CLEAR UP TOTALLY BY THE END OF THE MORNING. WILL PLAY IT MORE-CLOUDY THAN THAT FOR NOW. EVEN WITH THE SUN AND DOWNSLOPE...THE MAXES IN THE SE WILL ONLY BE IN THE M/U20S. THAT WOULD BE WELCOME IN THE NRN TIER WHERE MAXES MAY NOT MAKE IT INTO THE TWEENS /10-12F/. THE GUSTY WINDS WILL GRADUALLY SUBSIDE DURING THE DAY THURS WITH DAYTIME HIGHS 25-30F BELOW NORMAL. DAILY RECORD LOW/MINI-MAXES ARE IN JEOPARDY. IN ADDITION...LOW TEMPS THURS MORNING ACRS WRN PA WILL ALSO BE NEAR DAILY RECORD. SUFFICE IT TO SAY...IT MAY NOT BE THIS COLD AGAIN /ESPECIALLY DURING THE DAYLIGHT HOURS/ UNTIL NEXT WINTER. && .LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/... THE GOOD NEWS IS THAT THE COLD BLAST WILL BE SHORT-LIVED...WITH A RAPID MODERATION OCCURRING ON FRIDAY. BREEZY SW RETURN FLOW IN ADVANCE OF NRN CLIPPER SFC LOW TRACKING ACRS THE UPPER GREAT LAKES AND DOWNSLOPING SHOULD HELP TO BOOST TEMPS INTO THE 40S NORTH AND 50S SOUTH. THE MODELS TURN THE LOW TO THE NORTHEAST UP THE ST. LAWRENCE VLY ON DAY 5/SAT...DRAGGING A TRAILING/WEAK COLD FRONT ACRS THE NORTHEAST AND MID-ATL STATES. MODEL CONSENSUS INDICATES SOME LGT PCPN IS POSSIBLE WITH CHC POPS AS THE FRONT SHIFTS SEWD ACRS THE CWA. GEFS/EC ENSEMBLE MEANS SHOW THE LARGE SCALE PATTERN REVERTING BACK TO A WRN RIDGE/ERN TROUGH CONFIGURATION INTO EARLY NEXT WEEK. THIS HAS BEEN THE FAVORED/PREVAILING FLOW REGIME THIS WINTER...WITH A COLD POLAR VORTEX OVER EASTERN CANADA. A STRONG SFC HIGH PUSHING SEWD FROM THE UPPER MS VLY SHOULD DIRECT COLDER AIR INTO THE REGION BEHIND A REINFORCING FROPA ON SUNDAY...WITH TEMPS LKLY TRENDING LOWER BY DAY 7/MON. THE NON-NCEP OPRNL MODELS /12Z CMC AND ECMWF/ ARE MORE BULLISH ON CYCLOGENESIS INVOF THE GULF STREAM JUST EAST OF THE CAROLINAS...WITH THE NW EDGE OF POTNL PCPN SHIELD POSSIBLY REACHING SRN/SERN PA ON ST. PATRICK`S DAY. CONFIDENCE IS LOW GIVEN THE LARGE SPREAD BTWN THE GFS AND ECMWF/CMC. SOMETHING TO MONITOR IN THE DAYS TO COME. && .AVIATION /07Z WEDNESDAY THROUGH SUNDAY/... AS NOTED BELOW...VFR CONDITIONS WILL PREVAIL FOR A WHILE LONGER...MAIN AREA OF RAIN NORTH PA BORDER. 06Z TAFS SENT. EARLIER DISCUSSION BELOW. VFR CONDITIONS WILL CONTINUE THROUGH THE FIRST HALF OF THE OVERNIGHT PERIOD. SAT SHOWS LOW TO MID CLOUDS STREAMING THROUGH WITH CEILINGS AT MOST TAF SITES. THESE WILL SLOWLY LOWER AS THE NIGHT CONTINUES AND RESTRICTIONS WILL ARRIVE AS LIGHT RAIN /AND POSS SNOW NORTH/ AROUND 06Z IN THE NW...AND HEAVIER AREA OF PRECIP ARRIVING STARTING AROUND 12Z WED. BULK OF HEAVIER PRECIPITATION WILL BE BETWEEN LATE WED MORNING AND EARLY WEDNESDAY EVENING. WIDESPREAD ADVERSE CONDITIONS ON WED...WITH RAIN ACROSS MUCH OF THE AREA...SNOW ACROSS THE FAR NORTH...AND SOME RISK OF STRONG TSTMS NEAR THE MD BORDER. BY AFTERNOON...STRONG WIND FIELDS WILL BRING INCREASING NORTHERLY FLOW...LLWS...AND GUSTY WINDS UP TO 40 MPH. THESE CONTINUE THROUGH THE FIRST HALF OF THU AS VERY COLD AIR STAMPEDES INTO PA. WITH STRONG STORM DYNAMICS...CONCERN EXISTS FOR A BURST OF HEAVY WET CONVECTIVE SNOW /AND POSS THUNDER/ NEAR THE CENTER OF THE LOW WED/WED NIGHT. HAVE UPDATED TAFS WITH LLWS AT ALL CENTRAL AND WESTERN TAF SITES FROM 16Z TO AROUND 22Z. OUTLOOK... WED...WIDESPREAD MVFR- IFR RESTRICTIONS IN RAIN AND SNOW. STRONG N/NW WINDS DEVELOPING. LLWS. THU...STRONG/GUSTY N/NW WINDS...GRADUALLY DIMINISHING IN THE AFTERNOON. FRI-SUN...NO SIG WX EXPECTED. && .HYDROLOGY... WITH WARMER TEMPERATURES RAINFALL TODAY...WE EXPECT MODERATE RISES ON RIVERS AND STREAMS. THERE IS STILL ENOUGH ICE IN SPOTS TO LEAD TO ICE JAMS...THOUGH SIGNIFICANT DECAY HAS OCCURRED AT MANY LOCATIONS DUE TO THE RECENTLY WARM WEATHER. ANY ICE JAMS WILL BE ISOLATED IN NATURE. MONITOR WATER LEVELS CLOSELY FOR THE REST OF THE WEEK. && .CTP WATCHES/WARNINGS/ADVISORIES... WINTER STORM WARNING FROM 8 AM THIS MORNING TO 8 AM EDT THURSDAY FOR PAZ004-005. WINTER WEATHER ADVISORY FROM 8 AM THIS MORNING TO 8 AM EDT THURSDAY FOR PAZ006-010-011-037. WINTER WEATHER ADVISORY FROM 3 PM THIS AFTERNOON TO 8 AM EDT THURSDAY FOR PAZ017-024-033. && $$ SYNOPSIS...DANGELO/LA CORTE NEAR TERM...DANGELO SHORT TERM...DANGELO LONG TERM...STEINBUGL AVIATION...CERU/MARTIN/RXR HYDROLOGY...CTP
AREA FORECAST DISCUSSION
NWS BROWNSVILLE TX
1213 AM CDT WED MAR 12 2014 .DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW. && .AVIATION...A LITTLE DISAGREEMENT IN THE MODELS WRT LOW CIG AND VIS IN THE OVERNIGHT HOURS. 11-3.9 IMAGERY HINTING AT SOME CLOUD DEVELOPMENT SOUTH OF THE AREA AND HRRR AND NAM CONTINUE TO SHOW IFR DEVELOPING OVERNIGHT. NOT VERY CONFIDENT IN THIS SCENARIO BUT WILL SIDE WITH WORST CASE AND SHOW IFR CONDS 08-13Z. FRONT STILL ON TAP INTO THE VALLEY 12-13Z ACCORDING TO THE NAM WITH STRONG NORTHERLY WINDS EXPECTED BEHIND THE FRONT FOR MOST OF THE DAY. NO MOISTURE FOR THE FRONT SO NO PRECIPITATION EXPECTED WITH THE PASSAGE. CONDS IMPROVE AFTER SUNSET WITH WINDS FALLING TO 10 KTS OR LESS AFT 02Z. && .PREV DISCUSSION... /ISSUED 804 PM CDT TUE MAR 11 2014/ DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW. AVIATION...VFR CONDITIONS WILL PREVAIL EARLY IN THE TAF PERIOD AS THE S-SE LOW LEVEL FLOW BRINGS IN WAA WHICH ERODED AWAY THE MORNING CLD COVER AND FOG EARLIER TODAY. EXPECT SOME LOW CLDS AND FOG TO REFORM LATER TONIGHT AS FORECAST SOUNDINGS NEAR THE COASTLINE INDICATE THAT A FAIRLY SATURATED LOW LEVEL INVERSION WILL REFORM. THE FROPA EXPECTED EARLY TOMORROW MORNING WILL BRING AROUND SOLID VFR CONDITIONS THROUGH 00Z TOMORROW EVENING AS DRIER NORTHERLY LOW LEVEL FLOW ERODES AWAY ANY LINGERING FOG/LOW CLDS. THE EVENING TAF ISSUANCE LEANS MORE TOWARDS THE NAM GUIDANCE VERSUS THE GFS. PREV DISCUSSION... /ISSUED 301 PM CDT TUE MAR 11 2014/ .BIG WINDS TO WELCOME WEDNESDAY... SHORT TERM /NOW THROUGH WEDNESDAY NIGHT/...STRATUS LAYER IS LIFTING AND SCATTERING OVER ITS FINAL STRONGHOLD IN CAMERON COUNTY. OVER THE GULF IT WILL BE A LITTLE MORE PERSISTENT BUT SHOULD BEGIN TO CLEAR BY 4 PM OR SO. A TROUGH IS DIGGING INTO THE CENTRAL PLAINS THAT IS SENDING ANOTHER COLD FRONT TO THE SOUTH ACROSS NORTH CENTRAL TEXAS AND THAT WILL TAKE AIM ON THE AREA EARLY WEDNESDAY. TEMPERATURES ARE ON THEIR WAY UP INTO THE UPPER 70S TO PERHAPS LOW 80S AFTER A SLOW START AMID SOUTHWESTERLY SURFACE WINDS AND FULL SUNSHINE. TONIGHT...PATCHY FOG IS THE PRIMARY FORECAST CONCERN TONIGHT AS WINDS SLACKEN AHEAD OF THE APPROACHING FRONT. SOUTHWEST WINDS WILL BE A LITTLE HIGH FOR RADIATION FOG BUT SUSPECT WINDS WILL LAY DOWN MORE THAN PROGGED IN THE ARW/NMM GUIDANCE AND CONTINUED A PATCHY MENTION IN THE FORECAST. FOR NOW THE PROSPECTS OF DENSE FOG APPEAR PRETTY LOW. WEDNESDAY...ANOTHER FRONT WILL BLAST THROUGH THE AREA IN THE MORNING HOURS ON WEDNESDAY PROVIDING STRONG NORTH WINDS AND MUCH DRIER AIR. WIND VALUES APPROACH ADVISORY CRITERIA FOR MOST OF THE AREA AND MEET OR EXCEED IT IN THE COASTAL COUNTIES. WILL HOWEVER ALLOW THE EVENING SHIFT TO MAKE THE FINAL DETERMINATION ON IF AND WHERE THE ADVISORY SHOULD BE HOISTED. STRONG NORTH WINDS WILL ROUGHEN SEAS AND LEAD TO A HIGH RISK OF RIP CURRENTS AND WILL SEND A RIP CURRENT STATEMENT WITH THIS FORECAST PACKAGE FOR THE WILLACY AND CAMERON COUNTY BEACHES TO HIGHLIGHT AWARENESS DURING POPULAR SPRING BREAK TIMES ALTHOUGH WATER TEMPS IN THE UPPER 50S WILL LIKELY BE A GOOD DETRACTOR FROM SPENDING MUCH TIME IN THE WATER TOMORROW. HIGH TEMPERATURES SHOULD OCCUR EARLY IN THE DAY ON WEDNESDAY ALTHOUGH SKIES WILL CLEAR OUT BY MID TO LATE MORNING SO A LITTLE WARMING DURING THE AFTERNOON IS LIKELY DESPITE COLD AIR ADVECTION. WITH VERY LITTLE AVAILABLE MOISTURE KEPT RAINFALL CHANCES OUT OF THE FORECAST. WEDNESDAY NIGHT...MUCH COOLER FOR THE NIGHTTIME WEDNESDAY BUT NORTH WINDS WILL KEEP UP AT 5 TO 10 MPH THROUGH THE OVERNIGHT WITH LOWS IN THE LOW TO MID 40S DESPITE GENERALLY CLEAR SKIES. LONG TERM /THURSDAY THROUGH TUESDAY/...DETERMINISTIC FORECAST INCREASES IN DIFFICULTY TOWARD THE END OF THE PERIOD AS THE SPLIT- FLOW PATTERN CONTINUES TO WREAK HAVOC WITH GLOBAL MODEL DEPICTION OF THE SENSIBLE WEATHER FROM LATE WEEKEND INTO EARLY NEXT WEEK. IN THE MEANTIME...THE AFOREMENTIONED FLOW ENSURES NO SIGNIFICANT DEVELOPMENT OF A WARMING SPRINGTIME ATMOSPHERIC RIDGE...AND CONFIDENCE IS INCREASING FOR A FIFTH CONSECUTIVE MONTH WITH BELOW NORMAL TEMPERATURES FOR THE VALLEY. THE FORECAST FOR THURSDAY THROUGH SATURDAY IS LARGELY UNCHANGED. ZONAL FLOW ALOFT AND A QUICK RETURN TO EAST/NORTHEAST FLOW AT THE SURFACE ALLOWS A CHILLY START TO MODERATE NICELY ON THURSDAY. HOWEVER...GUT FEELING...MODEL TRENDS...WELL BELOW AVERAGE NEARSHORE WATER TEMPERATURES...AND RECENT EVENTS SUGGEST THIS SAME LOW LEVEL FLOW WILL BRING A QUICK RETURN OF A BROKEN TO PERHAPS OVERCAST DECK AT 4-5K FEET WHICH MAY PUT A LID ON JUST HOW HIGH TEMPERATURES CAN GO THURSDAY AFTERNOON. HAVE LEFT MAINLY MID TO HIGH 60S WHICH IS SOME 10-12 DEGREES BELOW AVERAGE FOR MARCH 13TH. THE CLOUDS WILL HANG AROUND AND SPREAD ACROSS THE ENTIRE REGION THURSDAY NIGHT AND FRIDAY AS SURFACE HUMIDITY PICKS UP AND MODERATION CONTINUES. NAM RAW TEMPERATURE DATA FOR FRIDAY MORNING WAS TOSSED AS THE CLOUDS AND SOUTHEAST FLOW WILL INSULATE...BUT WITH STILL RELATIVELY LOW DEWPOINTS EXPECT VALUES TO FALL SOME 5-10 DEGREES WITH LOWS RANGING THROUGH THE 50S BEFORE RECOVERING WELL INTO THE 70S TO AROUND 80 WITH SOME INCREASE IN SOUTHEAST WINDS FRIDAY AFTERNOON. ZONAL/WEST SOUTHWEST FLOW AT 500 MB ARRIVES SATURDAY WITH THE ECMWF A BIT MORE PRONOUNCED WITH LEAD SHORT WAVE AND SOME PRECIPITATION ACROSS EAST AND SOUTHEAST TEXAS. GFS A BIT MORE WESTERLY WITH ZONAL FLOW DOMINATING...AND THIS MAY BE THE BETTER SOLUTION. IN EITHER CASE...EXPECT CONSIDERABLE CLOUDS TO CONTINUE WITH A WARMER START (LOW TO MID 60S) AND TEMPERATURES JUST A HAIR ABOVE THOSE ON FRIDAY. THE MUDDLED FORECAST BEGINS BY SUNDAY. IN THE BIG PICTURE...BOTH ECMWF AND GFS DIVE A SHORT WAVE FROM NEW MEXICO THROUGH EL PASO ON INTO NORTH CENTRAL MEXICO BETWEEN SATURDAY NIGHT AND SUNDAY NIGHT. THE DIVERGENCE BEGINS THEREAFTER WITH THE ECMWF HOLDING ITS COURSE DIGGING THE TROUGH ALL THE WAY TO BAJA CALIFORNIA...WHILE THE GFS OPENS THE WAVE UP IN DURANGO WHILE EJECTING WAVES NORTHEAST THROUGH SOUTH TEXAS SUNDAY NIGHT THROUGH MONDAY NIGHT. DIFFERENCE APPEARS TO BE IN HANDLING/STRENGTH OF THE NEXT EASTERN U.S. TROUGH. THE GFS HAS A FLATTER SOLUTION WHICH OPENS THE DOOR FOR THE MORE ACTIVE SUBTROPICAL JET WHILE THE ECMWF BRINGS ENOUGH NORTHWEST FLOW ALOFT TO NUDGE AWAY ALL THE DEEP MOISTURE AND BEGIN A DRYING AND WARMING TREND. WHICH TO CHOOSE? VERY HARD TO SAY. GFS ENSEMBLES ARE IN GOOD AGREEMENT WITH THE OPEN WAVE THOUGH A FEW MEMBERS FOLLOW THE GFS INTO THE BAJA CUTOFF `GRAVEYARD` AS IT WERE. ALSO...VERY HARD TO COMPLETELY "FLIP" FROM A VERY LOW RAIN CHANCE NEXT MONDAY TO A 80 PERCENT CHANCE WITH QPF NEARING 2 INCHES...JUST YET. FOLLOWING THE MORE CONSISTENT ECMWF BUT OWING TO SOME ENERGY EJECTING TOWARD THE VALLEY...SIMILAR TO RECENT EVENTS...HAVE EXTENDED RAIN CHANCES INTO SUNDAY NIGHT AND EARLY MONDAY (NEAR THE RIVER). ALSO...THE GFS TEMPORARY PERIOD OF STRONG EAST WINDS /15 TO 25 MPH/ DOESN`T SEEM LIKELY AS `BRIDGING` HIGH PRESSURE CELLS ARE VERY UNCOMMON FOR DEEP SOUTH TEXAS. TEMPERATURES ARE DIFFICULT...BUT GIVEN THE NORTHERLY FLOW AND CLOUD COVER HAVE NUDGED BOTH SUNDAY AND MONDAY UP TO 10 DEGREES BELOW AVERAGE AND KEPT TUESDAY A FEW DEGREES BELOW AVERAGE (AVERAGES BY THEN RANGE FROM THE UPPER 70S TO MID 80S ON MARCH 18). MARINE...NOW THROUGH WEDNESDAY...MODERATE SOUTHEAST WINDS ARE EXPECTED THROUGH THE REST OF THE AFTERNOON AND TONIGHT. PATCHY FOG MAY REFORM AGAIN TONIGHT. A COLD FRONT WILL SWEEP ACROSS THE LOWER TEXAS COAST TONIGHT AND IS EXPECTED TO PRODUCE FREQUENT GALE FORCE GUSTS FOR AROUND 6 HOURS AND A GALE WARNING HAS BEEN ISSUED FOR ALL LOWER TEXAS COASTAL WATERS DURING THIS TIME. SMALL CRAFT ADVISORIES WILL LIKELY BE REQUIRED THROUGH THE REST OF THE AFTERNOON INTO WEDNESDAY NIGHT DUE TO PERSISTING NORTH WINDS AND ROUGH SEAS. THURSDAY THROUGH SUNDAY...MODERATE SEAS SUBSIDE TOWARD LIGHT TO MODERATE LEVELS THURSDAY AND CONTINUE THROUGH SATURDAY...WITH HEIGHTS AVERAGING IN THE 3-4 FOOT RANGE THROUGH THE PERIOD. NORTHEAST WINDS 15 KNOTS OR LESS VEER TO SOUTHEAST AT SIMILAR OR LOWER SPEEDS...PARTICULARLY NEAR THE COAST WHERE ROBUST MARINE LAYER HOLDS SWAY OVER THE VERY COOL WATERS FOR THIS TIME OF YEAR. FORECAST SUNDAY IS HIGHLY UNCERTAIN. GFS EASTERLY SURGE WAS THROWN OUT...WITH LIGHT WINDS SHIFTING NORTH AND INCREASING TOWARD ADVISORY /20 KNOT/ LEVELS SOMETIME DURING THE DAY WITH AN EQUIVALENT UPTICK IN SEAS. SHOULD BE ABLE TO GET A BETTER HANDLE ON SITUATION AS WE MOVE TOWARD THE WEEKEND. FIRE WEATHER...FORTUNATELY...GREENUP HAS BEGUN FOR MOST AREAS IN DEEP SOUTH TEXAS COURTESY OF THE LATE FEBRUARY WARMUP AND RECENT RAINS HAVE REPLENISHED/SUPPLEMENTED SOIL MOISTURE. THAT WILL BE ENOUGH TO KEEP THE THREAT OF RAPID FIRE SPREAD DOWN BEHIND WEDNESDAY`S SURGING NORTH WINDS AND LOWERING HUMIDITY. WE`RE EXPECTING SOME AREAS TO LAND IN THE 20-25% RH/25 MPH SUSTAINED WIND ZONE...BUT FUEL DRYNESS BEGINS ABOVE AVERAGE AND WILL NOT RECOVER IN JUST A DAY. THAT SAID...NOT A GREAT TIME TO BURN WITHIN 3-5 HOURS OF THE FRONT WITH GUSTS AT OR ABOVE 35 MPH. CLIMATE...AFTER NEARLY ONE THIRD OF MARCH...TEMPERATURES WERE RUNNING SOME 7 TO 10 DEGREES BELOW AVERAGE. WITH RECOVERY STALLED BY THE WEDNESDAY FRONT AND PERHAPS A DAY OR TWO AT OR JUST ABOVE AVERAGE FOLLOWED BY ANOTHER POTENTIAL COOLDOWN HEADING INTO THE 17TH/18TH...THE DEPARTURES WILL LIKELY REMAIN AT 5 TO 7 DEGREES WITH MORE THAN HALF OF THE MONTH GONE. AT THAT POINT...DAILY HIGH TEMPERATURES WOULD HAVE TO RUN 85 TO 90 WITH RELATIVELY MUGGY NIGHTS TO CATCH UP TO ZERO AND WHILE NOT OUT OF THE QUESTION BECOMES A HIGHLY UNLIKELY PROPOSITION ESPECIALLY WITH AN ACTIVE SPLIT JET EXPECTED TO CONTINUE. TIME WILL TELL...BUT MARCH COULD BE THE FIFTH CONSECUTIVE BELOW NORMAL MONTH FOR THE VALLEY. STAY TUENED. && .BRO WATCHES/WARNINGS/ADVISORIES... TX...HIGH RIP CURRENT RISK FROM 8 AM CDT THIS MORNING THROUGH THIS AFTERNOON FOR TXZ256-257. GM...GALE WARNING FROM 8 AM THIS MORNING TO 5 PM CDT THIS AFTERNOON FOR GMZ130-132-135-150-155-170-175. && $$ THIS PRODUCT IS ALSO AVAILABLE ON THE WEB AT: HTTP://WEATHER.GOV/RGV 55
AREA FORECAST DISCUSSION
NWS TAUNTON MA
1047 AM EDT WED MAR 12 2014 .SYNOPSIS... AN INTENSIFYING LOW PRESSURE SYSTEM APPROACHING FROM THE WEST WILL RESULT IN STEADY RAIN DEVELOPING THIS AFTERNOON. RAIN WILL TRANSITION TO FREEZING RAIN/SLEET THEN SNOW LATER TONIGHT AS TEMPERATURES CRASH ALLOWING FOR A FLASH FREEZE. BITTERLY COLD AIR AND STRONG WINDS ARE EXPECTED ON THURSDAY AS LINGERING SNOW SHOWERS TAPER OFF DURING THE AFTERNOON. MILDER WEATHER RETURNS FRI AND SAT...BEFORE ANOTHER INSTALLMENT OF COLDER AIR ARRIVES SUNDAY INTO EARLY NEXT WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... ***STEADY RAIN WILL NOT AFFECT MOST LOCATIONS UNTIL THIS AFTERNOON AND POSSIBLY NOT REACHING THE COASTAL PLAIN UNTIL EARLY EVENING*** 1045 AM UPDATE... 12/12Z OBSERVED SOUNDINGS INDICATE A PRONOUNCED WARM NOSE ALREADY IN PLACE ACROSS SOUTHERN NEW ENGLAND. REGIONAL RADARS SHOWING PRECIPITATION ON OUR DOORSTEP...BUT DRYING UP SOMEWHAT AS IT MOVES EAST. 12/14Z OBSERVATIONS STILL HAD RATHER LARGE DEW POINT DEPRESSIONS...PARTICULARLY TOWARD SOUTHEAST MA AND RI. EXPECTING THESE CONDITIONS TO CHANGE AS THE AFTERNOON PROGRESSES. DID ADJUST THE ARRIVAL TIME OF RAINFALL LATER THIS AFTERNOON...LEANING HEAVILY UPON THE 12/12Z NAM AND 12/13Z RAP GUIDANCE. OTHERWISE...MADE SOME MINOR TWEAKS TO NEAR TERM CONDITIONS TO KEEP THEM IN LINE WITH OBSERVED TRENDS. NO CHANGES TO EXISTING HEADLINES AT THIS TIME. PREVIOUS DISCUSSION FOLLOWS... LOW PRESSURE ACROSS THE OHIO VALLEY WILL MOVE EAST NORTHEAST TODAY AS IT INTENSIFIES. THE BULK OF THE FORCING/LIFT WILL BE WELL TO OUR NORTHWEST THIS MORNING. THEREFORE...OTHER THAN SCATTERED SHOWERS ACROSS THE INTERIOR THIS MORNING..MAINLY DRY WEATHER WILL PREVAIL. PTYPE SHOULD BE LIQUID ACROSS MOST OF THE REGION THIS MORNING...BUT A FEW WET SNOW FLAKES ARE POSSIBLE ACROSS THE HIGHER TERRAIN OF SOUTHWEST NH BUT NO ACCUMULATIONS ARE EXPECTED. STEADY RAIN WILL MOVE INTO AREAS NORTHWEST OF I-95 DURING THE MID TO LATE AFTERNOON. IT MAY TAKE UNTIL EARLY EVENING FOR THE STEADY RAIN TO REACH THE COASTAL PLAIN. GIVEN THE TRACK OF THE STORM...BULK OF THE MID LEVEL FORCING/FRONTOGENESIS WILL BE ACROSS THE INTERIOR THIS AFTERNOON. AS FOR PTYPE...MODELS SOUNDINGS INDICATE IT WILL BE WARM ENOUGH FOR RAIN FOR MUCH OF THE AFTERNOON FOR SOUTHERN NEW ENGLAND. HOWEVER...WILL HAVE TO WATCH FOR SOME POCKETS OF SLEET/FREEZING RAIN DEVELOPING BY LATE AFTERNOON IN SOUTHWEST NH/NORTHWEST MA AS SHALLOW COLD AIR BEGINS TO WORK INTO THE AREA. ACROSS THE REST OF THE REGION HIGH TEMPS WILL MAINLY BE IN THE 40S BUT SOME LOWER TO MIDDLE 50S ARE POSSIBLE IN THE WARM SECTION OF INTERIOR RHODE ISLAND/SOUTHEAST MA. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/... ***RAIN CHANGES TO BRIEF PERIOD OF SLEET/FREEZING RAIN AND THEN TO SNOW FROM NORTHWEST TO SOUTHEAST TONIGHT*** ***FLASH FREEZE OVERNIGHT WITH IMPACT ON THURSDAY AM RUSH HOUR A MUCH BIGGER CONCERN THAN SNOW ACCUMULATIONS*** INTENSE LOW PRESSURE WILL TRACK ACROSS RHODE ISLAND AND SOUTHEAST MA TONIGHT. ONCE THE LOW PASSES TO THE EAST...TEMPERATURES WILL CRASH AN RAIN WILL CHANGE TO SNOW. THE COLD AIR INITIALLY COMES DOWN SHALLOW...SO A BRIEF PERIOD OF SLEET/FREEZING RAIN IS POSSIBLE ESPECIALLY NORTH OF THE MA TURNPIKE. THE RAIN SHOULD CHANGE TO SLEET/FREEZING THEN SNOW ACROSS SOUTHWEST NH/WESTERN MA BY LATE EVENING...THEN BETWEEN 11 PM AND 3 AM ON THE COASTAL PLAIN. THE MID LEVEL CENTERS OF THE STORM TRACK TO THE WEST OF OUR REGION. THAT MEANS THAT THE VERY HEAVY SNOW AMOUNTS WILL CONFINED TO NORTHERN NEW ENGLAND. THE ONE THING WILL HAVE TO WATCH IS NORTHERN CHESHIRE/NORTHWEST HILLSBOROUGH COUNTIES WHERE SOME 6+ INCH SNOW AMOUNTS ARE POSSIBLE. WE WERE NOT CONFIDENT ENOUGH THAT THESE AMOUNTS WOULD COVER A LARGE ENOUGH PORTION OF THE COUNTIES FOR AN UPGRADE TO A WARNING...BUT SOMETHING LATER SHIFTS MAY HAVE TO CONSIDER. BEST CHANCE FOR THAT WILL BE ACROSS CHESHIRE COUNTY. ACROSS MOST OTHER AREAS...HAVE HOISTED A WINTER WEATHER ADVISORY EXCEPT FOR THE SOUTH COAST/CAPE AND ISLANDS. FOR MOST LOCATIONS WERE JUST EXPECTING 1 TO 2 INCHES OF SNOW...WITH PERHAPS 2 TO 4 INCHES NORTH OF ROUTE 2. HOWEVER...GIVEN THE POTENTIAL FOR A BRIEF PERIOD OF SLEET/FREEZING RAIN AND FLASH FREEZE WITH TEMPS EXPECTED TO CRASH INTO THE TEENS AND LOWER 20S...FELT AN ADVISORY WAS WORTH IT. ESPECIALLY WITH AN IMPACT EXPECTED ON THE THURSDAY AM RUSH HOUR. VERY IMPRESSIVE TEMPERATURE FALL AS SOME LOCATIONS IN RHODE ISLAND/SOUTHEAST MA MAY BE NEAR 50 THIS EVENING AND INTO THE UPPER TEENS LOWER 20S BY EARLY THU AM! THURSDAY... ***BITTERLY COLD WITH NORTHWEST WIND GUSTS OF 40 TO 50 MPH*** POTENT UPPER TROUGH WILL BE LAGGING BEHIND SURFACE LOW PRESSURE. THEREFORE...EXPECT SNOW SHOWERS TO CONTINUE THROUGHOUT THE MORNING BEFORE TAPERING OFF DURING THE AFTERNOON. TEMPERATURES WILL REMAIN IN THE UPPER TEENS AND LOWER 20S ALL DAY...WHICH IS VERY IMPRESSIVE COLD FOR THIS TIME OF YEAR. WIND CHILLS WILL BE BELOW ZERO. IN ADDITION...NORTHWEST WIND GUSTS OF 40 TO 50 MPH IN STRONG COLD ADVECTION WILL LIKELY REQUIRE THE NEED FOR A WIND ADVISORY. SINCE ITS A 3RD PERIOD EVENT AND THERE IS A LOT GOING ON WILL LET THE NEXT SHIFT HANDLE. && .LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/... *** TYPICAL MARCH WEATHER WITH A MIX OF SPRING AND WINTER-LIKE TEMPS THIS PERIOD *** OVERVIEW AND MODEL PREFERENCES... 12.00Z MODEL GUIDANCE SUITE IS IN FAIRLY GOOD SYNOPTIC SCALE AGREEMENT THROUGH THE WEEKEND AT LEAST BUT THEN BEGINS TO SHOW TYPICAL SPREAD/BIASES BY EARLY TO MID NEXT WEEK. THE KEY TO THE EXTENDED PERIOD WILL BE AN ARCTIC CUTOFF...THAT IS A PIECE OF THE POLAR VORTEX WHICH WILL GRADUALLY SETTLE ACROSS NORTHERN QUEBEC. THIS WILL BE EMBEDDED WITHIN A GENERAL POSITIVE NAO/AO REGIME...SUGGESTING A PROGRESSIVE STORM TRACK FROM THE ERN CONUS INTO THE NRN ATLANTIC. THEREFORE...THE KEY TO THE ULTIMATE STORM TRACK FOR EARLY NEXT WEEK WILL BE EXACTLY WHERE THE VORTEX AND ITS LONGWAVE TROF EXTENSION INTO THE ERN CONUS SETS UP. LATEST ECMWF AS WELL AS SOME OF THE GEFS/ECENS MEMBERS SUGGEST A SLIGHTLY LESS PROGRESSIVE TRACK...ALLOWING THE TROF TO SET UP MAINLY FROM THE GREAT LAKES INTO THE GULF OF MEXICO...PICKING UP ENERGY AND MOISTURE AS IT DOES. IT IS THIS SOLUTION THAT WOULD BRING THE BEST SHOT AT ANOTHER COASTAL STORM FOR EARLY NEXT WEEK. THE GFS SOLUTION IS MORE PROGRESSIVE AND SUPPRESSED TO THE S. ONCE AGAIN THOUGH...ASIDE FROM THE LONGWAVE TROF IT WILL REQUIRE ADDITIONAL SHORTWAVE ENERGY...BOTH FROM ARCTIC THE NRN PACIFIC. EACH OF THESE WAVES WILL NOT BE IN AN OBSERVATION RICH AREA FOR ABOUT 48+ HOURS...SO EXPECT THE TRACK TO SETTLE BETTER BY THE WEEKEND. FOR NOW...WILL BLEND OPERATIONAL GUIDANCE TO TAKE INTO ACCOUNT ALL POSSIBILITIES. DETAILS... THU NIGHT INTO FRI NIGHT... MAINLY DRY WX THROUGH THE PERIOD AS A RIDGE OF HIGH PRES NOSES OVER THE REGION FROM THE S. THU NIGHT IS EXPECTED TO START COLD...WITH AMBIENT MINS DROPPING INTO THE SINGLE DIGITS AND LOW TEENS. THIS WILL BE COMBINED WITH GUSTY NW WINDS AND MAY YIELD WIND CHILLS APPROACHING -10F TO -15F...SO NOT OUT OF THE QUESTION WIND CHILL ADVISORIES MAY BE NEEDED. OTHERWISE...TEMPERATURES REBOUND BY FRI...SHIFTING INTO THE LOW TO UPPER 30S AND ONLY DROPPING BACK INTO THE MID 20S TO LOW 30S THANKS TO INCREASING CLOUDS FRI NIGHT. SAT INTO SUN NIGHT... MODERATING TEMPERATURES EXPECTED UNDER WEAK WARM ADVECTION AHEAD OF A COLD FRONT SAT. THIS SHOULD ALLOW HIGHS TO REACH INTO THE MID 40S TO LOW 50S. THE COLD FRONT IS EXPECTED TO SLIDE THROUGH BY AFTERNOON...LIFT WITH IT IS WEAK...MAINLY FROM THE ISENTROPIC SUPPORT WITHIN THE WARM ADVECTION AHEAD OF IT. MOISTURE IS ALSO LACKING...WITH ONLY ABOUT A QUARTER TO HALF INCH PWAT VALUES. SO...A FEW SHOWERS MAY ACCOMPANY THIS FRONT AS IT PASSES...BUT CERTAINLY NOT A WASHOUT AND SOME AREAS MAY STAY DRY ALTOGETHER. COLD AND DRIER AIR SETTLES IN BEHIND THE FRONT SAT NIGHT INTO SUN NIGHT. LOWS IN THE LOW TO UPPER 20S EXPECTED SAT NIGHT UNDER CLOUD COVER AND HIGHS SUN ONLY IN THE 30S. ANOTHER ROUND OF COLD MINS SUN NIGHT...SETTLING IN THE TEENS AND LOW 20S. MON INTO TUE... THE COLD FRONT SETTLES OFFSHORE SUN...ORIENTING ALONG THE MEAN STORM TRACK...WHICH REMAINS A BIT IN QUESTION BASED ON THE OVERVIEW DISCUSSION ABOVE. THERE ARE INGREDIENTS FOR ANOTHER COASTAL WAVE OF LOW PRES TO DEVELOP...BUT ITS POTENCY AND TRACK ARE UNCERTAIN. AS MENTIONED ABOVE...CURRENT ECMWF /AS WELL AS GEFS/ECENS MEMBERS AND EVEN THE GLOBAL CMC/ SUGGEST IT MAY MAKE A CLOSE ENOUGH PASS FOR SOME WRAP-AROUND SNOWS ACROSS SRN NEW ENGLAND...BUT THE MORE PROGRESSIVE PATTERN /GFS AND SOME ENSEMBLE MEMBERS/ WOULD KEEP IT TOO FAR OFFSHORE. WILL NEED TO MONITOR ONCE SHORTWAVE ENERGY IN THE PACIFIC AND ARCTIC ARE BETTER SAMPLED. TOWARD THE MIDDLE OF NEXT WEEK... IN EITHER CASE...ANOTHER ROUND OF ARCTIC HIGH PRES LOOKS TO SETTLE ACROSS THE REGION AS ANY STORM SYSTEM MOVES FURTHER OFFSHORE...SO A PERIOD OF TEMPERATURES BELOW NORMAL LOOKS POSSIBLE. && .AVIATION /15Z WEDNESDAY THROUGH SUNDAY/... LOW...LESS THAN 30 PERCENT. MODERATE...30 TO 60 PERCENT. HIGH...GREATER THAN 60 PERCENT. SHORT TERM...THROUGH THURSDAY. TODAY...HIGH CONFIDENCE IN TRENDS...LOWER CONFIDENCE IN EXACT TIMING. VFR TO START THE MORNING. A FEW LIGHT SHOWERS POSSIBLE MAINLY TERMINALS N OF ROUTE 2 THIS MORNING...BUT SUSPECT BULK OF THE MORNING REMAINS DRY. EXPECTING CONDITIONS TO GRADUALLY LOWER TO MVFR THIS AFTERNOON...THEN TO IFR FROM ABOUT 17Z-21Z ACROSS THE WESTERN HALF OF SOUTHERN NEW ENGLAND AS RAIN ARRIVES. RAINFALL BECOMES HEAVIER THIS EVENING WITH MOST LOCATIONS SEEING IFR CONDITIONS AFTER 22Z. MAY SEE POCKETS OF LLWS OUT OF THE S AT TIMES THIS AFTERNOON...MOSTLY CAPE/ISLAND TERMINALS. TONIGHT...ASIDE FROM SLIGHT ADJUSTMENTS TO TIMING...MOSTLY ON TRACK FOR 12Z UPDATE....MAINLY IFR WITH SOME MVFR CONDITIONS. RAIN TRANSITIONS TO SNOW FROM NORTHWEST TO SOUTHEAST AS THE NIGHT WEARS ON. A BRIEF PERIOD OF SLEET/FREEZING RAIN IS POSSIBLE DURING THE TRANSITION ESPECIALLY NORTH OF THE MA TURNPIKE. NORTHERLY WINDS WILL GUST BETWEEN 20 AND 30 KNOTS BEHIND THE STORM BY LATE EVENING INTO THE OVERNIGHT HOURS. SOME LLWS POSSIBLE AS WINDS SHIFT TO THE NW RAPIDLY. THURSDAY...MVFR TO IFR CONDITIONS IN SNOW SHOWERS IN THE MORNING SHOULD IMPROVE SOME DURING THE AFTERNOON FROM WEST TO EAST. EXPECT CONDITIONS TO IMPROVE TO MVFR IF NOT VFR BY MID TO LATE AFTERNOON. NORTHWEST WIND GUSTS OF 30 TO 45 KNOTS EXPECTED. PRELIMINARY SNOWFALL FORECAST... BOS...1 TO 2 INCHES OVERNIGHT/THU AM PVD...1/2 TO 2 INCHES OVERNIGHT/THU AM BDL...1/2 TO 2 INCHES OVERNIGHT/THU AM ORH...1-3 INCHES LATE OVERNIGHT/THU AM MHT...2-5 INCHES LATE OVERNIGHT/THU AM KBOS TERMINAL...HIGH CONFIDENCE IN TAF THROUGH 18Z TODAY. MODERATE CONFIDENCE THEREAFTER. RAIN TRANSITIONS TO A BRIEF PERIOD OF SLEET/FREEZING RAIN BETWEEN 04Z AND 06Z TONIGHT. THEN A CHANGE TO ALL SNOW BETWEEN 06Z AND 08Z. KBDL TERMINAL...HIGH CONFIDENCE IN TAF THROUGH 18Z TODAY. MODERATE CONFIDENCE THEREAFTER. RAIN TRANSITIONS TO SNOW BETWEEN 02Z AND 05Z TONIGHT WITH A BRIEF PERIOD OF SLEET/FREEZING RAIN POSSIBLE DURING THE TRANSITION. OUTLOOK...THURSDAY NIGHT THROUGH SUNDAY. THU NIGHT THROUGH FRI NIGHT...HIGH CONFIDENCE. MAINLY VFR. STRONG NW WINDS DIMINISH THU NIGHT THEN SHIFT BACK TO THE SW ON FRI AND FRI NIGHT. SAT...MODERATE CONFIDENCE. MAINLY VFR...BUT OCCASIONAL MVFR POSSIBLE IN LIGHT RAIN/SNOW SHOWERS AHEAD OF A COLD FRONT. SUN...MODERATE CONFIDENCE. MAINLY VFR...BUT LOW PROBABILITY OF A LATE DAY OCEAN LOW PRES LEADING TO SOME SNOW SHOWERS PARTICULARLY SE MASS. MVFR/IFR WOULD BE POSSIBLE SHOULD THIS OCCUR. && .MARINE... FORECASTER CONFIDENCE LEVELS... LOW...LESS THAN 30 PERCENT. MODERATE...30 TO 60 PERCENT. HIGH...GREATER THAN 60 PERCENT. SHORT TERM /TONIGHT THROUGH THURSDAY/...HIGH CONFIDENCE. TODAY...WINDS/SEAS WILL BE BELOW SCA THRESHOLDS THROUGH THE MORNING. SOUTHERLY FLOW AHEAD OF LOW PRESSURE WILL RESULT IN 20 TO 25 KNOT GUSTS AND 3 TO 6 FOOT SEAS DEVELOP DURING THE AFTERNOON ACROSS THE SOUTHERN ATLANTIC WATERS. TONIGHT AND THURSDAY...NORTHWEST GALE FORCE WIND GUSTS OF 40 KNOTS DEVELOP LATE TONIGHT AND THURSDAY AS INTENSE LOW PRESSURE PASSES TO OUR EAST. IN ADDITION...MODERATE FREEZING SPRAY WILL DEVELOP DURING THU AFTERNOON AS AN USUALLY COLD AIR MASS FOR MID MARCH INVADES THE REGION. LATER SHIFTS WILL LIKELY NEED TO ISSUE A FREEZING SPRAY ADVISORY. IN ADDITION...SEAS ACROSS THE EASTERN ATLANTIC WATERS WILL BUILD TO BETWEEN 7 AND 13 FEET ON THURSDAY. OUTLOOK...THURSDAY NIGHT THROUGH SUNDAY... THURSDAY NIGHT...MODERATE CONFIDENCE NW GALES LIKELY ALONG WITH MODERATE FREEZING SPRAY POSSIBLE BY LATE DAY THU. VSBY REDUCED IN LIGHT SNOW DURING THE DAY. VERY ROUGH SEAS ESPECIALLY SOUTH WATERS FROM LEFTOVER SOUTH SWELLS COMBINING WITH NEW NW WIND WAVES. FRI...MODERATE CONFIDENCE. NW WIND BECOMING SW DURING THE AFTERNOON. A FEW GUSTS TO 25 KT POSSIBLE DURING THE AFTERNOON...WITH SEAS REMAINING ELEVATED ABOVE 5 FT ESPECIALLY ON THE OCEAN WATERS. FRI NIGHT INTO SAT...MODERATE CONFIDENCE. SW WINDS SHIFT TO THE W DURING THE DAY SATE. GUSTS SHOULD GENERALLY REMAIN BELOW SMALL CRAFT CRITERIA BUT A BUILDING SWELL OF 5-7 FT EXPECTED ON THE OCEAN WATERS. SUN... MODEST NW WIND MAY INCREASE BY SUN EVENING. DRY AND GOOD VSBY. && .TIDES/COASTAL FLOODING... NO FLOODING EXPECTED GIVEN RELATIVELY LOW ASTRO TIDES AND NOT MUCH WIND AND SURGE ANTICIPATED AS TRACK OF SURFACE LOW PRESSURE LOOKS TO BE DIRECTLY OVER SRN NEW ENGLAND. THIS WILL LIMIT THE ABILITY FOR FETCH IN ANY ONE DIRECTION. && .CLIMATE... NEAR RECORD COLD POSSIBLE THU NIGHT INTO EARLY FRIDAY. HERE ARE RECORD LOW TEMPERATURES FOR FRIDAY MARCH 14TH... BOSTON.......12/1896...FORECAST LOW...14 PROVIDENCE...12/1948...FORECAST LOW...13 BRADLEY ARPT..7/1948...FORECAST LOW...9 WORCESTER.....4/1948...FORECAST LOW...8 && .BOX WATCHES/WARNINGS/ADVISORIES... CT...WINTER WEATHER ADVISORY FROM 10 PM THIS EVENING TO NOON EDT THURSDAY FOR CTZ002>004. MA...WINTER WEATHER ADVISORY FROM 4 PM THIS AFTERNOON TO NOON EDT THURSDAY FOR MAZ002-003. WINTER WEATHER ADVISORY FROM 10 PM THIS EVENING TO NOON EDT THURSDAY FOR MAZ004>019-026. NH...WINTER WEATHER ADVISORY FROM 4 PM THIS AFTERNOON TO NOON EDT THURSDAY FOR NHZ011-012-015. RI...WINTER WEATHER ADVISORY FROM 10 PM THIS EVENING TO NOON EDT THURSDAY FOR RIZ001>005. MARINE...GALE WARNING FROM 8 AM TO 8 PM EDT THURSDAY FOR ANZ232>235-237- 254>256. GALE WARNING FROM 5 AM TO 8 PM EDT THURSDAY FOR ANZ230-236. GALE WARNING FROM 2 AM TO 8 PM EDT THURSDAY FOR ANZ231-250-251. && $$ SYNOPSIS...FRANK/DOODY NEAR TERM...BELK/FRANK/DOODY SHORT TERM...FRANK LONG TERM...DOODY AVIATION...BELK/FRANK/DOODY MARINE...FRANK/DOODY TIDES/COASTAL FLOODING...STAFF CLIMATE...STAFF
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
927 AM EDT WED MAR 12 2014 .SYNOPSIS... LOW PRESSURE IN SOUTHERN OHIO LATE THIS MORNING WILL INTENSIFY VERY RAPIDLY AS IT CROSSES NORTHERN NEW JERSEY THIS EVENING. IT WILL WHIP A VERY STRONG COLD FRONT ACROSS OUR AREA WITH THE STORM THEN RACING TO NOVA SCOTIA THURSDAY MORNING. LOW PRESSURE IN EASTERN CANADA FRIDAY AND SATURDAY WILL SEND ANOTHER COLD FRONT THROUGH THE MID ATLANTIC STATES EARLY SUNDAY. LOW PRESSURE THEN DEVELOPS ALONG THE SOUTHEAST COAST OF THE UNITED STATES NEXT MONDAY AND TUESDAY AND COULD PASS CLOSE TO OUR REGION. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... HIGH RESOLUTION MODELS SUCH AS THE HRRR SHOW THE PRIMARY AXIS OF PRECIPITATION ASSOCIATED WITH THE WAA GENERALLY NW OF OUR REGION THROUGH ABOUT 18Z. AFTER 18Z, COULD START TO SEE SHOWERS SPREADING FROM DELMARVA AND POCONOS ACROSS THE REST OF THE REGION. HOWEVER, GIVEN THE LIMITED INSTABILITY, IT STILL LOOKS LIKE THE MAIN SHOW WILL BE WITH THE COLD FRONT. GUSTY SSW WINDS TO 25 MPH POSSIBLE PHL AREA SOUTHWARD AFTER 3 PM. IAD 12Z SOUNDING OFFERS 73F FOR FULL SS. OUR FCST MAX TEMPS LOOK GOOD AT THIS TIME. AT 1030AM WE MAY ISSUE A FLASH FREEZE SPS FOR THE POCONOS TO BEGIN IN THE 7 PM TIME FRAME AS SHOWERY RAINS CHANGE TO FREEZING PRECIPITATION AND END BUT MOISTURE ON ROADS QUICKLY ICES OVER. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 AM THURSDAY/... COLD FRONT SHOULD SWEEP THROUGH THE REGION BETWEEN 22 AND 03Z. FORCING WITH THE COLD FRONT SHOULD BE ENOUGH TO OVERCOME THE STRONGLY SHEARED ENVIRONMENT FOR LINEAR CONVECTIVE SYSTEM. THINK THE SEVERE RISK WILL BE PRIMARILY OVER DELMARVA, FAR SE PA, AND S NJ WHERE THE CLOUDS WILL BE LAST TO ARRIVE, THUS WILL HAVE A BIT MORE HEATING TO ENHANCE THE INSTABILITY. THEN THE ATTENTION TURNS TO THE WINDS. THE STRONGEST WINDS ON LAND ARE EXPECTED IN THE POCONOS, WHERE TERRAIN EFFECTS WILL HELP MIXING, AND IN THE SOUTHERN HALF OF THE CWA WHERE THE ISALLOBARIC WIND COMPONENT IS EXPECTED TO BE THE STRONGEST. HAVE ISSUED A WIND ADVISORY FOR THESE LOCATIONS. THERE IS SOME RISK OF HIGH WIND WARNING FOR CAPE MAY AND COASTAL SUSSEX DUE TO THE FUNNELING EFFECTS THROUGH THE BAY, BUT WILL HOLD OFF ON THAT FOR NOW UNTIL WE SEE THE TREND OF UPSTREAM OBS BEHIND THE FRONT. && .LONG TERM /THURSDAY THROUGH TUESDAY/... AT THE START OF THE LONGTERM WE WILL BE DEALING WITH THE RAPID COOL-DOWN BEHIND THE INTENSE COLD FRONT AS IT MOVES WELL TO OUR EAST. WE WILL BE DRY BUT WITH LINGERING GUSTS AROUND 25 TO 30MPH AND TEMPERATURES NEARLY 20 DEGREES COLDER THAN NORMAL, WIND CHILL VALUES WILL REMAIN IN THE SINGLE DIGITS, POSSIBLY BELOW ZERO ACROSS THE NORTHERN ZONES, FOR MOST OF THE DAY. THE GOOD NEWS IS WE REALLY ONLY HAVE ONE DAY TO DEAL WITH THE ABRUPT COLD SHOT, THE BAD NEWS IS THAT THE WARMING TREND INTO THE WEEKEND LOOKS TO BE FLEETING, CREATING ANOTHER ROLLER COASTER EFFECT AS WE HEAD INTO THE NEW WORK WEEK. SOUTHWEST WINDS AHEAD OF THE NEXT COLD FRONT, PROGGED TO MOVE THROUGH LATER ON SATURDAY, WILL ALLOW TEMPERATURES TO CLIMB CLOSER TO NORMAL ON FRIDAY AND EVEN SLIGHTLY HIGHER ON SATURDAY. MUCH LIKE LAST WEEKEND, THE FRONTAL BOUNDARY ON SATURDAY IS NOT ALL THAT STRONG WITH LIMITED MOISTURE WITH MORE SPLIT FLOW EXPECTED. DO CARRY SLIGHT CHANCE POPS ACROSS THE NORTH WITH A FEW HUNDREDTHS OF PRECIPITATION POSSIBLE. THERMAL FIELDS WOULD ALLOW FOR SOME LIGHT SNOW SHOWERS ACROSS THE HIGHER TERRAIN AND A MIX CHANGING TO RAIN FURTHER SOUTH. SREF AND GEFS PROBS KEEP THE SOUTHERN HALF OF THE CWA DRY AT THIS TIME. SUNDAY WILL FEATURE AMPLE SUNSHINE AND A NEW COOLER AIRMASS. HIGH PRESSURE ACROSS THE UPPER MID-WEST SLIDES TO OUR NORTH HELPING TO REINFORCE COOLER TEMPERATURES. THIS WILL YIELD HIGHS SLIGHTLY BELOW AVERAGE. THE NEXT SYSTEM OF INTEREST BEGINS TO DEVELOP ALONG THE FRONTAL BOUNDARY THAT JUST DRAPED THROUGH THE REGION. THERE IS STILL A LOT OF UNCERTAINTY WITH THIS SYSTEM AS THE MID-LEVEL PATTERN DOESN`T PROVIDE A GOOD CONSENSUS AMONGST THE MID-RANGE GUIDANCE. LEANED HEAVILY ON THE WPC GUIDANCE AT THIS POINT BRINGING CHANCE POPS INTO THE REGION LATE SUNDAY NIGHT INTO MONDAY. THERMAL PROFILES AT THIS POINT WOULD INDICATE WIDESPREAD SNOW ACROSS THE NORTHERN HALF OF THE CWA WITH A BIT MORE MIXING ACROSS THE SOUTH. STILL PLENTY OF TIME TO FIGURE OUT HOW THIS SYSTEM WILL TRACK. && .AVIATION /13Z WEDNESDAY THROUGH SUNDAY/... THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY AND SURROUNDING AREAS. REMAINDER OF TODAY...VFR CIGS MOSTLY AOA 10000 FT BUT EXPECT MVFR CEILINGS TO MOVE IN FROM WEST TO EAST DURING THE AFTERNOON. MVFR VISIBILITIES WILL BE POSSIBLE WITH SHRA LATE IN THE DAY. THERE IS A RISK FOR ISOLATED TSRA BETWEEN 22Z AND 02Z NEAR THE COLD FRONTAL PASSAGE. OTHERWISE THE GRADIENT SSW WIND MAY GUST 25 KT AFTER 20Z KPHL REGION SOUTHWARD OTRW SE WINDS BECOMING S ELSEWHERE. TONIGHT...THE COLD FRONT THIS EVENING WILL BRING AN ABRUPT WIND SHIFT TO NW WITH GUSTS 30-40 KT. CONDITIONS SHOULD IMPROVE TO MAINLY VFR CIGS AOA 3000 FT WITHIN A FEW HOURS OF THE WIND SHIFT TO WEST NORTHWEST. OUTLOOK... THURSDAY...VFR. GUSTY NORTHWEST WINDS AROUND 30 TO 35 KNOTS POSSIBLE. FRIDAY...VFR. WINDS VEER TOWARDS THE SOUTHWEST AND COULD BE GUSTY AT TIMES. SATURDAY...MOSTLY VFR. COLD FRONT WILL CROSS THE REGION ON SATURDAY WITH SUB-VFR POSSIBLE IN RAIN SHOWERS. SUNDAY...VFR. && .MARINE... WINDS AND SEAS WILL CONTINUE TO INCREASE THROUGH THE DAY. HOWEVER, THE STRONGEST WINDS ARE EXPECTED WITH AND BEHIND THE COLD FRONT WHICH SHOULD ARRIVE THIS EVENING. WINDS WILL STAY UP FOR MUCH OF THE NIGHT. GALES ARE EXPECTED ACROSS THE REGION, AND STORM FORCE WINDS POSSIBLE IN THE LOWER DE BAY AND ADJACENT OCEAN WATERS DUE TO THE FUNNELING EFFECTS. WINDS ARE NOT EXPECTED TO SUBSTANTIALLY SUBSIDE OVERNIGHT. OUTLOOK... THURSDAY...CONTINUATION OF GALES THROUGH THE EVENING HOURS DROPPING TO SCA THEREAFTER. FRIDAY...SCA LIKELY WITH WINDS VEERING TOWARDS THE SOUTHWEST. SATURDAY - SUNDAY...SUB-SCA CONDITIONS EXPECTED BY LATE SATURDAY MORNING. WINDS SHIFT BACK TOWARDS THE WEST-NORTHWEST BEHIND A COLD FRONT LATER ON SATURDAY. && .HYDROLOGY... OPERATIONAL QPF AMOUNTS ARE NOT EXPECTED TO MAKE ANY OF OUR RIVERS REACH FLOOD LEVELS, THERE WILL BE RISES DUE TO THE COMBINED RAINFALL AND MELT OFF OF THE SNOW ACROSS THE NORTHERN HALF OF THE AREA. WITH ANY THUNDERSTORMS LATE IN THE DAY, THERE COULD ALSO BE SOME HEAVY RAINFALL THAT COULD PRODUCE URBAN AND POOR DRAINAGE TYPE FLOODING. SOMETHING TO KEEP AN EYE...PER THE HYDRO ENSEMBLES, WHICH ARE RUNNING WITH MORE RAINFALL THAN OPERATIONAL SOLUTIONS, 1.00 TO 1.50 INCHES OF BASIN-WIDE RAINFALL WOULD INCREASE THE FLOOD THREAT ACROSS THE NORTHERN HALF OF THE HSA. LUCKILY, WE DO HAVE SOME WIGGLE ROOM WITH 0.50 TO 0.75 INCHES IN THE FORECAST. && .EQUIPMENT... NWR...NO TONE ALERT TEST TODAY DUE TO POTENTIAL FOR REAL TIME WATCHES AND WARNING ISSUANCE`S THIS AFTERNOON. NWR TONE ALERT POSTPONED TIL THURSDAY FORENOON. PNS AND FB POSTED AS WELL. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...WIND ADVISORY FROM 6 PM THIS EVENING TO 11 AM EDT THURSDAY FOR PAZ054-055-060>062-070-071-101>104. NJ...WIND ADVISORY FROM 6 PM THIS EVENING TO 11 AM EDT THURSDAY FOR NJZ016>018-021>025. DE...WIND ADVISORY FROM 6 PM THIS EVENING TO 11 AM EDT THURSDAY FOR DEZ001>004. MD...WIND ADVISORY FROM 6 PM THIS EVENING TO 11 AM EDT THURSDAY FOR MDZ008-012-015-019-020. MARINE...GALE WARNING FROM 7 PM THIS EVENING TO 1 AM EDT FRIDAY FOR ANZ450>452. STORM WARNING FROM 11 PM THIS EVENING TO 11 AM EDT THURSDAY FOR ANZ431-453>455. GALE WARNING FROM 7 PM THIS EVENING TO 8 PM EDT THURSDAY FOR ANZ430. && $$ SYNOPSIS...DRAG 927 NEAR TERM...DRAG/JOHNSON 927 SHORT TERM...JOHNSON LONG TERM...HEAVENER AVIATION...DRAG/HEAVENER/JOHNSON 927 MARINE...DRAG/HEAVENER/JOHNSON HYDROLOGY...927 EQUIPMENT...GAINES/GORSE 927
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
950 AM EDT WED MAR 12 2014 .DISCUSSION... ...WINDY AND VERY WARM TODAY WITH SHOWERS AND A FEW STORMS... CURRENT...DEEPENING WINTER STORM OVER THE OH VALLEY CONTINUES TO MOVE ENE TOWARD THE MID ATLC STATES...WITH A WEAK SURFACE TROUGH OVER THE SERN CONUS BISECTING THE FL PANHANDLE THIS MORNING. THE TIGHTENING LCL PGRAD IS CAUSING SW SFC WINDS TO STRENGTHEN OVER THE PENINSULA. WATERVAPOR IMAGERY AND RUC ANLYS FIELDS SHOW A RAPIDLY DEFORMING MID-UPPER LEVEL TROUGH OVER NORTH FL...WHICH IS POISED TO QUICKLY MOVE ENE-NE OFF THE SERN SEABOARD BY AROUND NOON. LOCAL 88D DATA SHOWS SHOWERS AND A FEW TS WHICH DEVELOPED OVERNIGHT INTO THIS MORNING IN FAVORABLE MID LEVEL PVA/FORCED ASCENT MOVING RAPIDLY E TO ENE ACROSS THE NORTHERN HALF CWA. MORNING RAOBS HAVE CAPTURED THE MID LEVEL COOL POCKET WELL...WITH H50 TEMPS -13C TO -14C CREATING H85-H50 LAPSE RATES SUPPORTIVE OF SPORADIC CONVECTIVE CELLS BECOMING DEEP ENOUGH TO PRODUCE TS/LTG. IN ADDITION...DEEP LAYER WIND FIELDS HAVE ALSO STRENGTHENED TO WHERE STEERING WINDS ARE IN THE 40-50KT (45-55+MPH) RANGE FOR PRECIP. FORTUNATELY...DOWNDRAFTS DO NOT APPEAR TO BE VIGOROUS GIVEN THE TIME OF DAY AS HAVEN`T SEEN SFC STRONG CONVECTIVE GUSTS BENEATH ANY CELLS AS OF YET. REST OF TODAY...TROUGH EXITS STAGE RIGHT AS DIURNAL HEATING HEADS TOWARD IT PEAK. THIS PUTS THE TWO PRIMARY CONVECTIVE PARAMETERS ABOUT 4-6HR OUT OF PHASE FROM WORKING IN TANDEM TO PRODUCE A PRETTY DECENT EVENT. WHILE WIND FIELDS WILL REMAIN ROBUST...THE WEAKENING/ DEPARTING TROUGH WILL SPELL RISING MID LEVEL HGTS/TEMPS..WEAKENING THE SFC TROUGH AND ASCD CONVGC ZONE. ADDITIONALLY...H25 DIVG HAS ALREADY PUSHED OFFSHORE. THIS ALL PORTENDS AN INCREASINGLY UNFAVORABLE DYNAMICAL ENVIRONMENT FOR ISOLD STORMS BECOMING STRONG BY THIS AFTERNOON. ALL IN ALL...THE EVENT HAS BEEN WELL-HANDLED BY THE LAST COUPLE DAYS OF FORECASTS. LAKE WIND ADVISORY IS ALREADY UP...AND THAT LOOKS TO VERIFY NICELY. ABOUT THE ONLY TWEAK NEEDED WILL BE TO NUDGE POPS ACROSS THE NORTH AND CENTRAL UPWARD TO ACCOUNT FOR ONGOING ACTIVITY. && .AVIATION...CONVECTIVE SHOWERS AND A FEW TS TO PRODUCE LCL IFR CONDITIONS...BUT COVERAGE PROBABLY WARRANTS TEMPO MVFR CIGS/VSBYS FROM ABOUT MLB NWD. && .MARINE...NO CHGS NEEDED AS THE CAUTIONARY STMT BEYOND 20NM OFFSHORE WILL BE FOLLOWED BY AN SCA BY THIS EVENING. THE SCA WILL EXPAND TO COVER THE ENTIRE MAOR BY 03Z/11PM TONIGHT. && SHORT TERM/AVIATION...CRISTALDI LONG TERM/IMPACT WX/RADAR...SEDLOCK && .PREV DISCUSSION... /ISSUED 417 AM EDT WED MAR 12 2014/ ...STRONG COLD FRONT TONIGHT WILL BRING MUCH COOLER WEATHER THROUGH THURSDAY NIGHT... ...HAZARDOUS MARINE CONDITIONS DEVELOPING TONIGHT INTO THURSDAY... TONIGHT...WESTERLY FLOW IN THE EVENING WILL BECOME NW OVERNIGHT AS THE COLD FRONT MOVES INTO E CENTRAL FL TOWARD MIDNIGHT ACROSS NRN SECTIONS AND THEN THROUGH THE AREA OVERNIGHT. SHOULD SEE SOME CLOUDINESS ALONG THE FRONTAL BOUNDARY BUT MOISTURE DEPTH LOOKS TOO SCANT TO INCLUDE SHOWER MENTION. LOWS WILL RANGE FROM 45-50 ACROSS NRN LAKE AND VOLUSIA COUNTIES TO THE UPPER 50S ACROSS INLAND ST LUCIE AND MARTIN COUNTIES. THU-FRI... QUIET WX PATTERN THRU THE LATTER HALF OF THE WEEK AS THE POST FRONTAL HI PRES RIDGE BUILDS ACRS THE GOMEX/DEEP SOUTH. TIGHT PGRAD ACRS THE FL PENINSULA ON THU WILL GENERATE A BREEZY N/NW FLOW... RESULTING IN A STRONG COLD AIR ADVECTION THAT WILL KEEP MAX TEMPS ACRS MOST OF THE CWA AOB 70F...A 15-20F DEG DROP FROM WED. TEMPS WILL BEGIN TO RECOVER THU NIGHT AS THE RIDGE AXIS BUILDS OFF THE MID ATLC/SERN SEABOARD AND WINDS VEER TO E/NE. OCEAN MODIFIED AIR WILL KEEP MIN TEMPS IN THE L/M50S ALONG THE IMMEDIATE COAST. INTERIOR TEMPS...HOWEVER...WILL FALL INTO THE L/M40S ONCE AGAIN AS THE ONSHORE BREEZE WILL NOT HAVE SUFFICIENT TIME TO PUSH THE MODIFIED AIR MUCH FARTHER E THAN THE I-95 CORRIDOR. AIRMASS MODIFICATION WILL CONTINUE INTO FRI AS THE RIDGE BUILDS INTO THE W ATLC...FORCING WINDS TO VEER TO THE E/SE. MAX TEMPS IN THE U60S/L70S ALONG THE COAST AND M70S INTERIOR. SAT-TUE... ZONAL JET PATTERN ACRS THE SRN TIER STATES WILL GRADUALLY TRANSITION TO A LIFTING ORIENTATION OVER THE WEEKEND IN ADVANCE OF THE NEXT FRONTAL TROF. WITH RIDGING OVER THE W ATLC ALREADY IN PLACE...THE STAGE WILL BE SET FOR ANOTHER SLOW MOVING FRONTAL BNDRY THRU CENTRAL FL THAT WILL REQUIRE AN EXTENDED PD OF PRECIP IN THE FCST INTO EARLY NEXT WEEK. AS THE FRONT STALLS OVER THE PANHANDLE AND WINDS VEER TO THE S/SW... A WARM AIR ADVECTION PATTERN WILL DVLP THAT WILL PUSH TEMPS INTO THE U70S/L80S ON SAT...THEN INTO THE L/M80S AREAWIDE ON SUN. AS THE FRONT SLIDES INTO THE NRN PENINSULA...CLOUDS AND PERIODIC SHRAS WILL KEEP MAX TEMPS IN THE M/U70S...WHILE PREFRONTAL TEMPS OVER THE SRN CWA REMAIN IN THE L/M80S. MIN TEMPS GENERALLY IN THE U50S/L60S... EXCEPT L/M60S ALONG THE TREASURE COAST WHILE THIS PARTICULAR WX PATTERN USUALLY DOES NOT GENERATE LARGE OUTBREAKS OF STRONG/SVR WX...CANNOT RULE TSRAS OUT COMPLETELY ESP ACRS THE SRN CWA WHERE TEMPS WILL WARM INTO THE L/M80S DURING THE HEAT OF THE DAY. WILL GO WITH A MIX OF SHRAS/TSRAS THRU THE PD... CAPPING POPS ARND 40PCT SUN NIGHT INTO TUE. && .AVIATION...MAINLY VFR OUTSIDE OF SCATTERED SHRA ACTIVITY TODAY. GUSTY WSW WINDS THIS AFTERNOON WILL BECOME BREEZY FROM THE NW LATE TONIGHT. EXPECT VFR CONDS TO CONTINUE TONIGHT WITH A FRONTAL PASSAGE AT KMCO AROUND 07Z TONIGHT. && .MARINE... SW WINDS TO 15-20 KNOTS OFFSHORE WILL BECOME WEST BY THIS EVENING AND THEN STRONG AND GUSTY FROM THE NW OVERNIGHT. SMALL CRAFT ADVISORIES WILL BEGIN ACROSS THE OFFSHORE WATERS THIS EVENING AND NEAR SHORE WATERS BY 10 PM TONIGHT AS WINDS STRENGTHEN FROM THE NW AFTER MIDNIGHT. SEAS WILL BUILD TO 8-9 FT OFFSHORE. THU-THU NIGHT...HAZARDOUS BOATING CONDITIONS WILL CONTINUE BUT WILL IMPROVE SLOWLY AS THE POST FRONTAL HI PRES RIDGE BUILDS ACRS THE GOMEX/DEEP SOUTH AND ALLOWS THE LCL PGRAD TO SLACKEN. SFC/BNDRY LYR WINDS TO DIMINISH FROM A FRESH TO STRONG NW BREEZE AT SUNRISE TO A MODERATE TO FRESH NRLY BREEZE AT SUNSET...THEN TO A GENTLE TO MODERATE E/NE BREEZE OVERNIGHT. SEAS SUBSIDING FROM 6-8FT NEARSHORE AND 8-10FT OFFSHORE TO 3-5FT NEARSHORE AND 4-6FT OFFSHORE. FRI-FRI NIGHT...WINDS BCMG A GENTLE TO MODERATE ERLY BREEZE THRU THE AFTN...THEN E/SE OVERNIGHT AS THE HI PRES RIDGE BUILDS ACRS THE FL PENINSULA AND INTO THE SW ATLC. SEAS TO 3-4FT NEARSHORE AND 4-6FT OFFSHORE SUBSIDING TO 2-4FT NEARSHORE AND 3-5FT OFFSHORE. SAT-SUN...ATLC HI PRES RIDGE WILL BE THE DOMINANT WX FEATURE THRU THE UPCOMING WEEKEND AS A NEW COLD FRONT PUSHES INTO THE DEEP SOUTH AND STALLS OVER THE FL PANHANDLE. INTERACTION BTWN THESE TWO SYSTEMS WILL GENERATE A GENTLE TO MODERATE S/SERLY BREEZE WITH SEAS 2-4FT ON SAT SUBSIDING TO 2-3FT SUN. CHC SHRAS ON SUN N OF SEBASTIAN INLET... SLGT CHC S OF THE INLET. && .FIRE WEATHER... MIN RHS FROM 45-50 PERCENT TODAY...BUT GUSTY WINDS FROM THE SW/WSW IN THE AFTERNOON AND BECOMING NW OVERNIGHT WILL POSE A FIRE WX CONCERN. THU...STRONG POST FRONTAL DRY AIR ADVECTION WITH BREEZY N/NW SFC/TRANSPORT WINDS...MIN RH VALUES ARND 20-25PCT INTERIOR FROM OSCEOLA COUNTY NWD AND 30-35PCT ALONG THE COAST AND OKEECHOBEE COUNTY. FRI...HI PRES WILL BUILD ACRS THE FL PENINSULA AND INTO THE W ATLC...ALLOWING WINDS TO VEER TO THE E. THE ONSHORE FLOW WILL MODIFY THE DRY AIR...THOUGH RH VALUES BLO 35PCT WILL LINGER ALONG AND N OF THE I-4 CORRIDOR. && .CLIMATE... RECORD HIGH TEMPS FOR TODAY... DAB 90 1935 MCO 89 2001 MLB 90 1962 VRB 88 1962 && .PRELIMINARY POINT TEMPS/POPS... DAB 83 47 63 47 / 40 10 10 0 MCO 84 51 68 45 / 40 10 10 10 MLB 85 54 65 51 / 40 10 10 10 VRB 86 58 66 52 / 40 10 10 10 LEE 83 45 66 42 / 40 10 10 0 SFB 83 50 67 45 / 40 10 10 0 ORL 83 51 67 46 / 40 10 10 10 FPR 86 60 67 53 / 40 10 10 10 && .MLB WATCHES/WARNINGS/ADVISORIES... FL...LAKE WIND ADVISORY FROM 1 PM THIS AFTERNOON TO 8 PM EDT THIS EVENING FOR COASTAL VOLUSIA-INDIAN RIVER-INLAND VOLUSIA- MARTIN-NORTHERN BREVARD-NORTHERN LAKE-OKEECHOBEE-ORANGE- OSCEOLA-SEMINOLE-SOUTHERN BREVARD-SOUTHERN LAKE-ST. LUCIE. AM...SMALL CRAFT ADVISORY FROM 11 PM THIS EVENING TO 10 PM EDT THURSDAY FOR COASTAL WATERS FROM FLAGLER BEACH TO VOLUSIA BREVARD COUNTY LINE OUT 20 NM-COASTAL WATERS FROM SEBASTIAN INLET TO JUPITER INLET OUT 20 NM-COASTAL WATERS FROM VOLUSIA BREVARD COUNTY LINE TO SEBASTIAN INLET OUT 20 NM. SMALL CRAFT ADVISORY FROM 8 PM THIS EVENING TO 4 AM EDT FRIDAY FOR WATERS FROM FLAGLER BEACH TO VOLUSIA BREVARD COUNTY LINE 20 TO 60 NM OFFSHORE-WATERS FROM SEBASTIAN INLET TO JUPITER INLET 20 TO 60 NM OFFSHORE-WATERS FROM VOLUSIA BREVARD COUNTY LINE TO SEBASTIAN INLET 20 TO 60 NM OFFSHORE. && $$
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
933 AM EDT WED MAR 12 2014 .SYNOPSIS... A STRONG COLD FRONT WILL APPROACH THE AREA FROM THE WEST TODAY AND WILL MOVE THROUGH TONIGHT...FOLLOWED BY UNSEASONABLY COOL HIGH PRESSURE THROUGH FRIDAY. ANOTHER COLD FRONT WILL MOVE SOUTH OVER THE WEEKEND...LIKELY PUSHING INTO SOUTHEAST SOUTH CAROLINA AND SOUTHEAST GEORGIA SUNDAY. THE FRONT WILL EITHER STALL OVER THE AREA OR CONTINUE PUSHING SOUTH INTO FLORIDA EARLY NEXT WEEK. AT LEAST ONE WAVE OF LOW PRESSURE WILL DEVELOP ALONG THIS FRONT. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... THROUGH MIDDAY/EARLY AFTERNOON...EXPECT BRIEF PERIODS OF SUNSHINE EAST OF I-95... BUT WIDESPREAD WRAP-AROUND CLOUDS AND ISOLATED/SCATTERED SHOWERS WILL PUSH THROUGH THE REGION. OVERALL...CLOUD COVER WILL HOLD TEMPS DOWN THROUGH MIDDAY/EARLY AFTERNOON. THEN...DEEP LAYER DRYING COULD RESULT IN DECREASING CLOUD COVER ALLOWING TEMPERATURES WILL PUSH TO AROUND 80F BY LATE AFTERNOON. HOWEVER...LATEST RUC SOUNDINGS SUGGESTS THAT CLOUDS WILL PERSIST. IF THIS OCCURS...WE WILL HAVE TO LOWER TEMPERATURES THIS AFTERNOON. ALSO...AS SURFACE LOW PRESSURE DEEPENS NORTH OF THE REGION...THE SURFACE PRESSURE GRADIENT WILL TIGHTEN AND LOW-LEVEL WINDS WILL STRENGTHEN. THIS WILL TRANSLATE TO GUSTY W/SW WINDS ACROSS THE FORECAST AREA. EVEN WITH CLOUD COVER...GUSTS 30-35 MPH SHOULD OCCUR. IF CLOUDS BREAK UP AND ALLOW FOR WARMER TEMPS AND A DEEPER MIXED LAYER...GUSTS AS HIGH AS 35-40 MPH COULD OCCUR. AS OF LATE WEDNESDAY MORNING...NO PLANS TO ISSUE A WIND ADVISORY. LAKE WINDS...SOUTHWEST WINDS WILL INCREASE TODAY INTO THE 20-25 KT RANGE AHEAD OF AN APPROACHING COLD FRONT. A LAKE WIND ADVISORY STARTS AT 10 AM AND RUNS THROUGH THE DAY. && .SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY/... TONIGHT...THE STRONG COLD FRONT APPROACHING FROM THE WEST WILL PUSH INTO THE AREA AND IS CURRENTLY PROGGED TO PASS THROUGH IN THE 8PM TO MIDNIGHT TIME FRAME. CANNOT RULE OUT A FEW SHOWERS WITH FROPA. OTHERWISE...WINDS WILL VEER TO W/NW AND REMAIN QUITE GUSTY THROUGH MUCH OF THE OVERNIGHT IN THE STOUT COLD ADVECTION. MODELS SHOW AT LEAST A BAND OF LOW/MID LEVEL CLOUDS ALONG THE FRONT...WITH VERY LIGHT PRECIPITATION. I HAVE KEPT THE FORECAST DRY DUE TO THE LACK OF MOISTURE DEPTH. SKIES WILL RAPIDLY CLEAR BEHIND THE FRONT AND TEMPERATURES WILL QUICKLY FALL. THE FORECAST HAS LOWS FALLING INTO THE 30S FOR MOST OF THE FORECAST AREA...WITH SOME MID 30S FAR INLAND. THIS IS A DECREASING TREND FROM PREVIOUS MODEL RUNS...SO THERE IS A VERY LOW CHANCE FOR AN ADVECTIVE FREEZE IN THESE FAR INLAND AREAS. THE PROBABILITY IS LOW ENOUGH TO NOT MENTION IN THE HWO...BUT IT IS SOMETHING TO KEEP AN EYE ON. THURSDAY...HIGH PRESSURE WILL BUILD FROM THE WEST AS THE UPPER TROUGH SHIFTS OFFSHORE. HOWEVER...A LINGERING CHILLY AIR MASS WILL KEEP TEMPS WELL BELOW NORMAL IN THE MID TO UPPER 50S WITH DIMINISHING WINDS THROUGH THE DAY. TEMPS WILL DROP QUICKLY THURSDAY NIGHT DUE TO RATHER IDEAL RADIATIONAL COOLING CONDITIONS AS HIGH PRESSURE SLIDES EAST AND BECOMES CENTERED OVER SOUTHEAST NORTH CAROLINA. BY DAYBREAK FRIDAY TEMPERATURES SHOULD FREEZING OR SLIGHTLY BELOW FOR MOST AREAS...ESPECIALLY WEST OF HIGHWAY 17 IN SOUTH CAROLINA CLOSER TO THE CENTER OF THE HIGH. THUS...A FREEZE WATCH WILL LIKELY BE ISSUED FOR THESE AREAS LATER TODAY. FRIDAY...TEMPS WILL MODERATE AS HIGH PRESSURE SLIDES INTO THE ATLANTIC ALLOWING A MILDER SOUTH/SOUTHEAST FLOW TO SET UP. HIGHS SHOULD REACH THE LOWER TO MID 60S...EXCEPT LIKELY STRUGGLING TO REACH 60 AT THE COAST DUE TO THE ONSHORE WINDS OFF THE COOLER ATLANTIC WATERS...STILL BELOW NORMAL FOR THIS TIME OF YEAR. DRY WEATHER WILL CONTINUE FRIDAY NIGHT ALTHOUGH CLOUDS WILL BE ON THE INCREASE WHICH WILL KEEP LOW TEMPS CLOSER TO THE MID/UPPER 40S...WARMEST ALONG THE COAST. SATURDAY...ATLANTIC HIGH PRESSURE WILL BEGIN TO WEAKEN AS A COLD FRONT APPROACHES FROM THE NORTHWEST. DESPITE INCREASING CLOUDS AND POSSIBLY A FEW SHOWERS TEMPERATURES SHOULD REACH NEAR 70 DEGREES MOST LOCALES WITH SOME MID 70S POSSIBLE DEPENDING ON THE AMOUNT OF CLOUD COVER. LAKE WINDS...WINDS WILL INCREASE TONIGHT IMMEDIATELY BEHIND THE FRONT...WITH GUSTS TO AROUND OR JUST ABOVE 30 KTS IN THE EARLY MORNING HOURS. A LAKE WIND ADVISORY RUNS THROUGH THE NIGHT UNTIL MIDDAY THURSDAY. && .LONG TERM /SATURDAY NIGHT THROUGH TUESDAY/... CONDITIONS LOOK UNSETTLED THROUGH EARLY NEXT WEEK AS A COLD FRONT IS EXPECTED TO PUSH SOUTH INTO SOUTHERN SOUTH CAROLINA SUNDAY AND THEN EITHER STALL OUT OR CONTINUE TO PUSH SOUTH INTO FLORIDA SUNDAY NIGHT INTO MONDAY. HIGH PRESSURE SHOULD THEN BUILD IN THROUGH WEDNESDAY WITH GENERALLY DRY CONDITIONS AND MODERATING TEMPS. && .AVIATION /13Z WEDNESDAY THROUGH SUNDAY/... THIS MORNING...LOW LEVEL MOISTURE WILL SUPPORT AT LEAST OCCASIONAL FLIGHT RESTRICTIONS INCLUDING LIFR CEILINGS AND MVFR/IFR VISIBILITY. ADDITIONAL SHOWERS WILL ALSO PUSH THROUGH THE REGION...ESPECIALLY THE KCHS AREA. THIS AFTERNOON...VFR WITH W/SW WINDS GUSTING TO AROUND 30 KT. LOW PROBABILITY FOR MVFR CEILINGS EARLY. THIS EVENING...COLD FROPA WILL BRING A WIND SHIFT TO THE WNW ACCOMPANIED BY GUSTS TO AT LEAST 30 KT...WITH A LOW PROBABILITY FOR MVFR CEILINGS. 06Z OF LATER...GUSTS SETTLE BACK TO AROUND 25 KT...AND THE PROBABILITY FOR VFR CONDITIONS IS HIGH. EXTENDED AVIATION OUTLOOK...VFR THURSDAY THROUGH SATURDAY. MVFR CEILINGS AND/OR VSBYS LIKELY SATURDAY NIGHT INTO AT LEAST EARLY MONDAY ALONG WITH SHOWERS DUE TO A COLD FRONT. GUSTY WINDS EXPECTED INTO THURSDAY AFTERNOON. && .MARINE... TODAY AND TONIGHT...GUSTY SW WINDS WILL CREATE SCA CONDITIONS TODAY. THEN...CONDITIONS ACROSS THE LOCAL WATERS WILL QUICKLY DETERIORATE TONIGHT AS A STRONG COLD FRONT MOVES THROUGH FROM THE WEST. WINDS WILL INCREASE FURTHER AS THE INITIAL PUNCH OF THE COLD FRONT THIS EVENING. WINDS WILL TURN MORE W/NW AND FREQUENT GUSTS TO 35 KTS ARE EXPECTED ACROSS ALL NEARSHORE WATERS...AND GUSTS TO 40 KTS FOR THE OUTER WATERS. GALE WARNINGS HAVE BEEN HOISTED FOR ALL ZONES OUTSIDE OF THE CHARLESTON HARBOR STARTING THIS EVENING AND RUNNING THROUGH THURSDAY MORNING. THE CHARLESTON HARBOR MAY SEE AN ISOLATED GUST TO 35 KTS IMMEDIATELY BEHIND THE FRONT...BUT WINDS OF THIS STRENGTH ARE EXPECTED TO BE TEMPORARY ENOUGH TO NOT GO WITH A GALE WARNING THERE. THE DAY SHIFT MAY NEED TO REEVALUATE LATER FOR POSSIBLE UPGRADE. DANGEROUS MARINE CONDITIONS ARE EXPECTED TONIGHT WITH THE COMBINATION OF THE GALES AND BUILDING SEAS. SEAS WILL BE AS HIGH AS 6-7 FT RIGHT AROUND 20 NM AND UP TO 9-10 FT BEYOND 20 NM. THURSDAY THROUGH MONDAY...CONDITIONS WILL IMPROVE DRASTICALLY THURSDAY AS THE PRESSURE GRADIENT...LOW-LEVEL JET AND COLD ADVECTION WANE. ALL HEADLINES FOR THE NEARSHORE WATERS SHOULD COME DOWN IN THE MORNING WITH THE OUTER WATERS FOLLOWING IN THE AFTERNOON. GENERALLY TRANQUIL CONDITIONS THEN EXPECTED THURSDAY NIGHT THROUGH SATURDAY BEFORE THINGS LIKELY GO DOWNHILL EARLY NEXT WEEK AS A COLD FRONT PUSHES INTO THE AREA FROM THE NORTH SUNDAY WITH THE WORST CONDITIONS LIKELY SUNDAY NIGHT AND/OR MONDAY AS LOW PRESSURE PUSHES OFFSHORE AND HIGH PRESSURE BUILDS FROM THE NORTH. && .CHS WATCHES/WARNINGS/ADVISORIES... GA...NONE. SC...LAKE WIND ADVISORY UNTIL NOON EDT THURSDAY FOR SCZ045. MARINE...SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR AMZ352- 354. GALE WARNING FROM 8 PM THIS EVENING TO 8 AM EDT THURSDAY FOR AMZ350-352-354-374. SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR AMZ350- 374. SMALL CRAFT ADVISORY UNTIL NOON EDT THURSDAY FOR AMZ330. && $$ SYNOPSIS... NEAR TERM...SPR SHORT TERM...RJB LONG TERM...RJB AVIATION...SPR MARINE...BSH/RJB/SPR
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1053 AM CDT WED MAR 12 2014 .DISCUSSION... 700 AM CDT HAVE LET THE FEW NORTHERN PARTS OF THE ADVISORY EXPIRE AT 7 AM WITH NO OTHER CHANGES TO CURRENT HEADLINES. SOME MINOR ADJUSTMENTS MADE TO THE MORNING FORECAST. THE PRIMARY UPPER WAVE IS VERY WELL-DEFINED ON SATELLITE AND RADAR THIS MORNING AND ITS CENTER CONTINUES TO MOVE EAST INTO INDIANA. THE SYSTEM DEFORMATION CONTINUES TO INTENSIFY WITH THE COLD CONVEYOR BELT STRENGTHENING INTO THE SYSTEM WITH COPIOUS AMOUNTS OF MOISTURE CONTINUING TO BE WRAPPED INTO THE BACKSIDE. ALSO HIGHLIGHTING THIS IS A BLOSSOMING OF REFLECTIVITY ACROSS EAST CENTRAL ILLINOIS AS OF 700 AM WITH LIKELY SOME 1 IN/HR RATES TEMPORARILY SEEN WITH THIS AS IT MOVES EAST THROUGH 9 AM. FROM MONITORING LOCAL MEDIA AND BASED ON A PLETHORA OF REPORTS...BLOWING SNOW IS OCCURRING IN MANY PLACES DUE TO THE WINDS. SO CONCERNS ABOUT THE SNOW COMPOSITION POTENTIALLY BEING TOO WET SEEM TO BE PUT TO REST IN MANY PLACES THANKS TO THE HIGHER END DEGREE OF GUSTS. IN ADDITION...THE NORTHERN STREAM SHORT WAVE CONTINUES TO DIG SOUTH AND HAVE INFLUENCE ON THE MAIN SYSTEM. THIS WAVE IN ITSELF IS PRODUCING LIGHT PRECIP IN THE FORM OF MAINLY FLURRIES BUT ALSO SOME FREEZING DRIZZLE. THIS IS ASSOCIATED WITH FOCUSED ASCENT WITHIN/ABOVE LOW-LEVEL CONVERGENCE. THESE ELEMENTS ON THE RAP DROP SOUTHWARD INTO NORTHERN ILLINOIS THIS MORNING AND HIGH RES GUIDANCE SUCH AS THE LOCAL ARW AND THE HOPWRF ENSEMBLE BRING LIGHT PRECIP SOUTH AS WELL. HAVE INCREASED THE COVERAGE OF FLURRIES IN THE FORECAST AND ADDED FREEZING DRIZZLE MENTION AS FORECAST PROFILES REMAIN BORDERLINE FOR EITHER...WHICH LINES UP WITH OBSERVATIONAL TRENDS. HAVE KEPT THE FREEZING DRIZZLE MENTION WEST OF CHICAGO FOR THE TIME BEING BASED ON EXTRAPOLATION OF ONGOING REPORTS. MTF //PREV DISCUSSION... 350 AM CDT REST OF TODAY... THE PRIMARY CHANGES IN THE FORECAST WERE A QUICKER DIMINISHING OF ANY LIGHT SNOW CHANCES AS WELL AS TO BUMP UP TEMPERATURES NAMELY THIS MORNING. DEEP DRY AIR AND SUPPRESSION LOOK TO MOVE QUICKLY INTO THE AREA BY LATE MORNING BEHIND THIS SYSTEM. CONTINUING LOW- LEVEL CYCLOGENESIS OFF TO THE EAST WILL DRIVE COLD AIR ADVECTION INTO THE REGION...AND PROFILES WILL BE SUPPORTIVE OF KEEPING STRATOCU AND MAYBE SOME FLURRIES INTO EARLY TO MID AFTERNOON. TEMPERATURES ARE FAIRLY HOMOGENEOUS UP TO CENTRAL/SOUTHERN WI EARLY THIS MORNING...SO LOW-LEVEL THERMAL ADVECTION LOOKS TO BE NEUTRAL THROUGH DAYBREAK AND THEN SLIGHT COLD AIR ADVECTION THIS MORNING. TEMPERATURES SHOULD LEVEL OUT THIS AFTERNOON AS AT LEAST SOME MARCH SUNSHINE OFFSETS ANY COLD AIR ADVECTION. WITH NOT AS COLD OF AIR QUICKLY COMING INTO THE AREA...THE POSSIBILITY OF LAKE EFFECT SNOW SHOWERS INTO NORTHWEST INDIANA LOOKS QUITE SMALL...BUT POSSIBLY SOME CLOUDS GENERATING INTO LAKE AND PORTER COUNTIES THIS AFTERNOON. TONIGHT... HIGH PRESSURE WILL MOVE OVER THE REGION TONIGHT AND SET THE STAGE FOR A COLD NIGHT BY MID-MARCH STANDARDS. HIGH CLOUDS DO LOOK TO SPILL INTO THE WESTERN FORECAST AREA AS THE NIGHT PROGRESSES AS A SHEARED WEAK SHORTWAVE DROPS SOUTHWARD ON THE BACKSIDE OF THE DEVELOPING LONGWAVE TROUGH. BUT IT LOOKS TO BE A LITTLE TOO LATE TO STOP TEMPERATURES FROM DROPPING NICELY OVER FRESH SNOW COVER THIS EVE INTO EARLY OVERNIGHT. FORECAST TEMPERATURES WITH MODEST CONFIDENCE ARE SINGLE DIGITS IN OUTLYING AREAS TO 10 TO 15 IN THE CHICAGO METRO. THAT LINES UP WITH THE 850MB TEMPERATURES OF -12C TO -15C ACROSS THE FORECAST AREA BY TONIGHT...WHICH ARE WELL BELOW CLIMO. IF CLOUDS WERE TO MOVE IN QUICKER IT WOULD RESULT IN MINS POTENTIALLY QUITE A BIT WARMER. THURSDAY AND BEYOND... WHILE THE UPPER FLOW PATTERN BECOMES NORTHWEST AND REMAINS DECENTLY ACTIVE THROUGH THE REST OF THE FORECAST PERIOD...WE REMAIN ON THE ANTICYCLONIC SIDE. THUS WE LOOK TO FREQUENTLY MISS THE BEST FORCING AND DEEPER SATURATION OF EACH QUICK-MOVING SYSTEM. IT DOES MAKE FOR A CHALLENGE WITH TEMPERATURES...ESPECIALLY WEIGHING RECENT SNOW COVER AND OCCASIONALLY PASSING CLOUD COVER. DO MAINTAIN A SMALL CHANCE FOR LIGHT SNOW THURSDAY MORNING IN NORTHERN AREAS AS WARM AIR ADVECTION ALOFT MOVES IN BEHIND THE TROUGH. SATURATION LOOKS TO BE A PROBLEM...BUT THE ISENTROPIC ASCENT IS PRETTY STRONG AND SATURATION ON BOTH THE NAM AND GFS IS DEPICTED TO BE LOW ENOUGH FOR SOME LIGHT SNOW TO REACH THE GROUND...IF IT CAN MATERIALIZE. FRIDAY LOOKS MILD WITH TEMPERATURES POTENTIALLY PUSHING 50 DEGREES AS WEST SOUTHWEST LOW-LEVEL FLOW BRING A WARM SECTOR OF ONE OF THE QUICK-MOVING SYSTEMS INTO OUR AREA. HAVE GONE WITH AN GFS/EC BLEND FOR THE WEEKEND INTO EARLY NEXT WEEK. THE GFS IS CONSIDERABLY COLDER FOR SUNDAY AND SUNDAY NIGHT WITH A STRONG CANADIAN HIGH PASSING OVER THE AREA...WHILE THE EC FAVORS THIS FEATURE TO BE MUCH FURTHER NORTH AND WEAKER. MTF && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 16Z... * MVFR CIGS THIS MORNING AND EARLY AFTERNOON. * GUSTY NORTH WINDS WITH MAX GUSTS ARND 30KT THIS MORNING...DIMINISHING AND BECOMING NNW EARLY THIS AFTN. GUSTS ARND 25 KT EXPECTED THIS AFTN. JEE //DISCUSSION...UPDATED 12Z... BACK EDGE OF LIGHT SNOW WILL BE MOVING EAST OF MDW/GYY BY 13Z. STILL THE POTENTIAL FOR SOME FLURRIES OR VERY LIGHT SNOW THROUGH MID MORNING BUT NOT EXPECTING ANY VIS/CIGS RESTRICTIONS. BLOWING SNOW/LOW DRIFTING SNOW WILL CONTINUE INTO THIS AFTERNOON. ONCE SNOW ENDS...MVFR CIGS WILL CONTINUE INTO THIS AFTERNOON THEN SCATTER OUT BY EVENING WITH SKC EXPECTED TONIGHT. STRONG/GUSTY NORTHERLY WINDS WILL CONTINUE THROUGH MUCH OF THE DAY WITH GUSTS AS HIGH AS 30KTS FOR THE NEXT FEW HOURS...THEN GUSTS WILL DIMINISH INTO THE MID/UPPER 20KT RANGE BY LATE MORNING... SLOWLY AND STEADILY DIMINISHING THROUGH AFTERNOON WITH GUSTS ENDING WITH SUNSET. WINDS WILL BECOME LIGHT AND VARIABLE OVERNIGHT AS A RIDGE OF HIGH PRESSURE MOVES ACROSS THE AREA. CMS //ORD AND MDW CONFIDENCE...UPDATED 16Z... * HIGH CONFIDENCE IN CIG TRENDS...MEDIUM-HIGH CONFIDENCE IN WHEN MVFR CIGS LIFT TO VFR. * HIGH CONFIDENCE IN ALL OTHER FORECAST ELEMENTS. JEE //OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z... * THURSDAY NIGHT...DRY/VFR. * FRIDAY...DRY/VFR. GUSTY WESTERLY WINDS. * SATURDAY THROUGH SUNDAY...DRY/VFR. * TUESDAY...CHANCE OF RAIN/SNOW. MVFR POSSIBLE. && .MARINE... 210 PM CDT LOW PRESSURE OVER THE CENTRAL PLAINS WILL CONTINUE TO DEEPEN AS IT TRACKS EAST ACROSS SOUTHERN ILLINOIS TONIGHT AND INTO THE OHIO VALLEY WEDNESDAY. AS THE LOW TRACKS SOUTH AND THEN SOUTHEAST OF THE LAKE...HIGH PRESSURE WILL ALSO BUILD ACROSS THE UPPER GREAT LAKES REGION...SETTING UP STRONG NORTH WINDS. THE COMBINATION OF A STRONG GRADIENT AND STRONG COLD ADVECTION WILL LEAD TO WINDS QUICKLY INCREASING TO GALES BY LATE THIS EVENING. THE LATEST GUIDANCE HAS BEEN RELATIVELY CONSISTENT IN INDICATING THE POTENTIAL FOR HIGH END GALES BY LATE WEDNESDAY MORNING AND EARLY AFTERNOON...WITH THE STRONGEST GALES OVER THE SOUTHERN PORTIONS OF THE LAKE...INCLUDING THE NEARSHORE WATERS. BY WEDNESDAY EVENING...THE HIGH PRESSURE WILL BEGIN TO SPREAD ACROSS LAKE MICHIGAN ALLOWING WINDS TO SUBSIDE BELOW GALE FORCE. BY THURSDAY NIGHT...THE HIGH WILL PUSH TO THE SOUTHEAST OF THE LAKE AS A CLIPPER DROPS OUT OF NORTHERN ALBERTA AND SWINGS JUST NORTH OF THE UPPER GREAT LAKES ON FRIDAY. WITH THE SFC HIGH SAGGING OFF THE SERN COAST...A PERIOD OF SWLY WINDS WILL DEVELOP AHEAD OF AN APPROACHING COLD FRONT TRAILING FROM THE CLIPPER. ANTICIPATE A PERIOD OF BRISK SLY TO SWLY WINDS FOR THURSDAY NIGHT THROUGH FRIDAY...BUT MORE GALES ARE NOT EXPECTED AT THIS TIME. AS THE CLIPPER TURNS NEWD INTO QUEBEC...IT WILL DRAG A WEAK COLD FRONT DOWN THE LAKE WITH ANOTHER ARCTIC HIGH BUILDING IN BEHIND THE FRONT. 25-30KT NORTH WINDS WILL SET UP FOLLOWING THE FROPA FOR SATURDAY NIGHT AND SUNDAY...BUT AS THE HIGH SPREADS ACROSS THE GREAT LAKES SUNDAY NIGHT...WINDS SHOULD BECOME MORE LIGHT AND VARIABLE. KREIN && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...GALE WARNING...LMZ080-LMZ669-LMZ671-LMZ673-LMZ675-LMZ740-LMZ741- LMZ742-LMZ743-LMZ744-LMZ745-LMZ777-LMZ779-LMZ870-LMZ872- LMZ874-LMZ876-LMZ878 UNTIL 10 PM WEDNESDAY. GALE WARNING...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-LMZ567- LMZ868 UNTIL 7 PM WEDNESDAY. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
920 AM CDT WED MAR 12 2014 .DISCUSSION... 700 AM CDT HAVE LET THE FEW NORTHERN PARTS OF THE ADVISORY EXPIRE AT 7 AM WITH NO OTHER CHANGES TO CURRENT HEADLINES. SOME MINOR ADJUSTMENTS MADE TO THE MORNING FORECAST. THE PRIMARY UPPER WAVE IS VERY WELL-DEFINED ON SATELLITE AND RADAR THIS MORNING AND ITS CENTER CONTINUES TO MOVE EAST INTO INDIANA. THE SYSTEM DEFORMATION CONTINUES TO INTENSIFY WITH THE COLD CONVEYOR BELT STRENGTHENING INTO THE SYSTEM WITH COPIOUS AMOUNTS OF MOISTURE CONTINUING TO BE WRAPPED INTO THE BACKSIDE. ALSO HIGHLIGHTING THIS IS A BLOSSOMING OF REFLECTIVITY ACROSS EAST CENTRAL ILLINOIS AS OF 700 AM WITH LIKELY SOME 1 IN/HR RATES TEMPORARILY SEEN WITH THIS AS IT MOVES EAST THROUGH 9 AM. FROM MONITORING LOCAL MEDIA AND BASED ON A PLETHORA OF REPORTS...BLOWING SNOW IS OCCURRING IN MANY PLACES DUE TO THE WINDS. SO CONCERNS ABOUT THE SNOW COMPOSITION POTENTIALLY BEING TOO WET SEEM TO BE PUT TO REST IN MANY PLACES THANKS TO THE HIGHER END DEGREE OF GUSTS. IN ADDITION...THE NORTHERN STREAM SHORT WAVE CONTINUES TO DIG SOUTH AND HAVE INFLUENCE ON THE MAIN SYSTEM. THIS WAVE IN ITSELF IS PRODUCING LIGHT PRECIP IN THE FORM OF MAINLY FLURRIES BUT ALSO SOME FREEZING DRIZZLE. THIS IS ASSOCIATED WITH FOCUSED ASCENT WITHIN/ABOVE LOW-LEVEL CONVERGENCE. THESE ELEMENTS ON THE RAP DROP SOUTHWARD INTO NORTHERN ILLINOIS THIS MORNING AND HIGH RES GUIDANCE SUCH AS THE LOCAL ARW AND THE HOPWRF ENSEMBLE BRING LIGHT PRECIP SOUTH AS WELL. HAVE INCREASED THE COVERAGE OF FLURRIES IN THE FORECAST AND ADDED FREEZING DRIZZLE MENTION AS FORECAST PROFILES REMAIN BORDERLINE FOR EITHER...WHICH LINES UP WITH OBSERVATIONAL TRENDS. HAVE KEPT THE FREEZING DRIZZLE MENTION WEST OF CHICAGO FOR THE TIME BEING BASED ON EXTRAPOLATION OF ONGOING REPORTS. MTF //PREV DISCUSSION... 350 AM CDT REST OF TODAY... THE PRIMARY CHANGES IN THE FORECAST WERE A QUICKER DIMINISHING OF ANY LIGHT SNOW CHANCES AS WELL AS TO BUMP UP TEMPERATURES NAMELY THIS MORNING. DEEP DRY AIR AND SUPPRESSION LOOK TO MOVE QUICKLY INTO THE AREA BY LATE MORNING BEHIND THIS SYSTEM. CONTINUING LOW- LEVEL CYCLOGENESIS OFF TO THE EAST WILL DRIVE COLD AIR ADVECTION INTO THE REGION...AND PROFILES WILL BE SUPPORTIVE OF KEEPING STRATOCU AND MAYBE SOME FLURRIES INTO EARLY TO MID AFTERNOON. TEMPERATURES ARE FAIRLY HOMOGENEOUS UP TO CENTRAL/SOUTHERN WI EARLY THIS MORNING...SO LOW-LEVEL THERMAL ADVECTION LOOKS TO BE NEUTRAL THROUGH DAYBREAK AND THEN SLIGHT COLD AIR ADVECTION THIS MORNING. TEMPERATURES SHOULD LEVEL OUT THIS AFTERNOON AS AT LEAST SOME MARCH SUNSHINE OFFSETS ANY COLD AIR ADVECTION. WITH NOT AS COLD OF AIR QUICKLY COMING INTO THE AREA...THE POSSIBILITY OF LAKE EFFECT SNOW SHOWERS INTO NORTHWEST INDIANA LOOKS QUITE SMALL...BUT POSSIBLY SOME CLOUDS GENERATING INTO LAKE AND PORTER COUNTIES THIS AFTERNOON. TONIGHT... HIGH PRESSURE WILL MOVE OVER THE REGION TONIGHT AND SET THE STAGE FOR A COLD NIGHT BY MID-MARCH STANDARDS. HIGH CLOUDS DO LOOK TO SPILL INTO THE WESTERN FORECAST AREA AS THE NIGHT PROGRESSES AS A SHEARED WEAK SHORTWAVE DROPS SOUTHWARD ON THE BACKSIDE OF THE DEVELOPING LONGWAVE TROUGH. BUT IT LOOKS TO BE A LITTLE TOO LATE TO STOP TEMPERATURES FROM DROPPING NICELY OVER FRESH SNOW COVER THIS EVE INTO EARLY OVERNIGHT. FORECAST TEMPERATURES WITH MODEST CONFIDENCE ARE SINGLE DIGITS IN OUTLYING AREAS TO 10 TO 15 IN THE CHICAGO METRO. THAT LINES UP WITH THE 850MB TEMPERATURES OF -12C TO -15C ACROSS THE FORECAST AREA BY TONIGHT...WHICH ARE WELL BELOW CLIMO. IF CLOUDS WERE TO MOVE IN QUICKER IT WOULD RESULT IN MINS POTENTIALLY QUITE A BIT WARMER. THURSDAY AND BEYOND... WHILE THE UPPER FLOW PATTERN BECOMES NORTHWEST AND REMAINS DECENTLY ACTIVE THROUGH THE REST OF THE FORECAST PERIOD...WE REMAIN ON THE ANTICYCLONIC SIDE. THUS WE LOOK TO FREQUENTLY MISS THE BEST FORCING AND DEEPER SATURATION OF EACH QUICK-MOVING SYSTEM. IT DOES MAKE FOR A CHALLENGE WITH TEMPERATURES...ESPECIALLY WEIGHING RECENT SNOW COVER AND OCCASIONALLY PASSING CLOUD COVER. DO MAINTAIN A SMALL CHANCE FOR LIGHT SNOW THURSDAY MORNING IN NORTHERN AREAS AS WARM AIR ADVECTION ALOFT MOVES IN BEHIND THE TROUGH. SATURATION LOOKS TO BE A PROBLEM...BUT THE ISENTROPIC ASCENT IS PRETTY STRONG AND SATURATION ON BOTH THE NAM AND GFS IS DEPICTED TO BE LOW ENOUGH FOR SOME LIGHT SNOW TO REACH THE GROUND...IF IT CAN MATERIALIZE. FRIDAY LOOKS MILD WITH TEMPERATURES POTENTIALLY PUSHING 50 DEGREES AS WEST SOUTHWEST LOW-LEVEL FLOW BRING A WARM SECTOR OF ONE OF THE QUICK-MOVING SYSTEMS INTO OUR AREA. HAVE GONE WITH AN GFS/EC BLEND FOR THE WEEKEND INTO EARLY NEXT WEEK. THE GFS IS CONSIDERABLY COLDER FOR SUNDAY AND SUNDAY NIGHT WITH A STRONG CANADIAN HIGH PASSING OVER THE AREA...WHILE THE EC FAVORS THIS FEATURE TO BE MUCH FURTHER NORTH AND WEAKER. MTF && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 14Z... * MVFR CIGS THIS MORNING AND EARLY AFTERNOON. * GUSTY NORTH WINDS WITH MAX GUSTS ARND 30KT THIS MORNING...DIMINISHING AND BECOMING NNW EARLY THIS AFTN. GUSTS ARND 25 KT EXPECTED THIS AFTN. JEE //DISCUSSION...UPDATED 12Z... BACK EDGE OF LIGHT SNOW WILL BE MOVING EAST OF MDW/GYY BY 13Z. STILL THE POTENTIAL FOR SOME FLURRIES OR VERY LIGHT SNOW THROUGH MID MORNING BUT NOT EXPECTING ANY VIS/CIGS RESTRICTIONS. BLOWING SNOW/LOW DRIFTING SNOW WILL CONTINUE INTO THIS AFTERNOON. ONCE SNOW ENDS...MVFR CIGS WILL CONTINUE INTO THIS AFTERNOON THEN SCATTER OUT BY EVENING WITH SKC EXPECTED TONIGHT. STRONG/GUSTY NORTHERLY WINDS WILL CONTINUE THROUGH MUCH OF THE DAY WITH GUSTS AS HIGH AS 30KTS FOR THE NEXT FEW HOURS...THEN GUSTS WILL DIMINISH INTO THE MID/UPPER 20KT RANGE BY LATE MORNING... SLOWLY AND STEADILY DIMINISHING THROUGH AFTERNOON WITH GUSTS ENDING WITH SUNSET. WINDS WILL BECOME LIGHT AND VARIABLE OVERNIGHT AS A RIDGE OF HIGH PRESSURE MOVES ACROSS THE AREA. CMS //ORD AND MDW CONFIDENCE...UPDATED 14Z... * HIGH CONFIDENCE IN CIG TRENDS...MEDIUM-HIGH CONFIDENCE IN WHEN MVFR CIGS LIFT TO VFR. * HIGH CONFIDENCE IN ALL OTHER FORECAST ELEMENTS. JEE //OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z... * THURSDAY NIGHT...DRY/VFR. * FRIDAY...DRY/VFR. GUSTY WESTERLY WINDS. * SATURDAY THROUGH SUNDAY...DRY/VFR. * TUESDAY...CHANCE OF RAIN/SNOW. MVFR POSSIBLE. && .MARINE... 210 PM CDT LOW PRESSURE OVER THE CENTRAL PLAINS WILL CONTINUE TO DEEPEN AS IT TRACKS EAST ACROSS SOUTHERN ILLINOIS TONIGHT AND INTO THE OHIO VALLEY WEDNESDAY. AS THE LOW TRACKS SOUTH AND THEN SOUTHEAST OF THE LAKE...HIGH PRESSURE WILL ALSO BUILD ACROSS THE UPPER GREAT LAKES REGION...SETTING UP STRONG NORTH WINDS. THE COMBINATION OF A STRONG GRADIENT AND STRONG COLD ADVECTION WILL LEAD TO WINDS QUICKLY INCREASING TO GALES BY LATE THIS EVENING. THE LATEST GUIDANCE HAS BEEN RELATIVELY CONSISTENT IN INDICATING THE POTENTIAL FOR HIGH END GALES BY LATE WEDNESDAY MORNING AND EARLY AFTERNOON...WITH THE STRONGEST GALES OVER THE SOUTHERN PORTIONS OF THE LAKE...INCLUDING THE NEARSHORE WATERS. BY WEDNESDAY EVENING...THE HIGH PRESSURE WILL BEGIN TO SPREAD ACROSS LAKE MICHIGAN ALLOWING WINDS TO SUBSIDE BELOW GALE FORCE. BY THURSDAY NIGHT...THE HIGH WILL PUSH TO THE SOUTHEAST OF THE LAKE AS A CLIPPER DROPS OUT OF NORTHERN ALBERTA AND SWINGS JUST NORTH OF THE UPPER GREAT LAKES ON FRIDAY. WITH THE SFC HIGH SAGGING OFF THE SERN COAST...A PERIOD OF SWLY WINDS WILL DEVELOP AHEAD OF AN APPROACHING COLD FRONT TRAILING FROM THE CLIPPER. ANTICIPATE A PERIOD OF BRISK SLY TO SWLY WINDS FOR THURSDAY NIGHT THROUGH FRIDAY...BUT MORE GALES ARE NOT EXPECTED AT THIS TIME. AS THE CLIPPER TURNS NEWD INTO QUEBEC...IT WILL DRAG A WEAK COLD FRONT DOWN THE LAKE WITH ANOTHER ARCTIC HIGH BUILDING IN BEHIND THE FRONT. 25-30KT NORTH WINDS WILL SET UP FOLLOWING THE FROPA FOR SATURDAY NIGHT AND SUNDAY...BUT AS THE HIGH SPREADS ACROSS THE GREAT LAKES SUNDAY NIGHT...WINDS SHOULD BECOME MORE LIGHT AND VARIABLE. KREIN && .LOT WATCHES/WARNINGS/ADVISORIES... IL...WINTER STORM WARNING...ILZ013-ILZ014-ILZ020-ILZ021-ILZ022-ILZ023 UNTIL 11 AM WEDNESDAY. WINTER WEATHER ADVISORY...ILZ019-ILZ032-ILZ033-ILZ039 UNTIL 11 AM WEDNESDAY. IN...WINTER STORM WARNING...INZ001-INZ002 UNTIL 11 AM WEDNESDAY. WINTER WEATHER ADVISORY...INZ010-INZ011-INZ019 UNTIL 11 AM WEDNESDAY. LM...GALE WARNING...LMZ080-LMZ669-LMZ671-LMZ673-LMZ675-LMZ740-LMZ741- LMZ742-LMZ743-LMZ744-LMZ745-LMZ777-LMZ779-LMZ870-LMZ872- LMZ874-LMZ876-LMZ878 UNTIL 10 PM WEDNESDAY. GALE WARNING...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-LMZ567- LMZ868 UNTIL 7 PM WEDNESDAY. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION...UPDATED
NWS CHICAGO/ROMEOVILLE IL
706 AM CDT WED MAR 12 2014 .DISCUSSION... 700 AM CDT HAVE LET THE FEW NORTHERN PARTS OF THE ADVISORY EXPIRE AT 7 AM WITH NO OTHER CHANGES TO CURRENT HEADLINES. SOME MINOR ADJUSTMENTS MADE TO THE MORNING FORECAST. THE PRIMARY UPPER WAVE IS VERY WELL-DEFINED ON SATELLITE AND RADAR THIS MORNING AND ITS CENTER CONTINUES TO MOVE EAST INTO INDIANA. THE SYSTEM DEFORMATION CONTINUES TO INTENSIFY WITH THE COLD CONVEYOR BELT STRENGTHENING INTO THE SYSTEM WITH COPIOUS AMOUNTS OF MOISTURE CONTINUING TO BE WRAPPED INTO THE BACKSIDE. ALSO HIGHLIGHTING THIS IS A BLOSSOMING OF REFLECTIVITY ACROSS EAST CENTRAL ILLINOIS AS OF 700 AM WITH LIKELY SOME 1 IN/HR RATES TEMPORARILY SEEN WITH THIS AS IT MOVES EAST THROUGH 9 AM. FROM MONITORING LOCAL MEDIA AND BASED ON A PLETHORA OF REPORTS...BLOWING SNOW IS OCCURRING IN MANY PLACES DUE TO THE WINDS. SO CONCERNS ABOUT THE SNOW COMPOSITION POTENTIALLY BEING TOO WET SEEM TO BE PUT TO REST IN MANY PLACES THANKS TO THE HIGHER END DEGREE OF GUSTS. IN ADDITION...THE NORTHERN STREAM SHORT WAVE CONTINUES TO DIG SOUTH AND HAVE INFLUENCE ON THE MAIN SYSTEM. THIS WAVE IN ITSELF IS PRODUCING LIGHT PRECIP IN THE FORM OF MAINLY FLURRIES BUT ALSO SOME FREEZING DRIZZLE. THIS IS ASSOCIATED WITH FOCUSED ASCENT WITHIN/ABOVE LOW-LEVEL CONVERGENCE. THESE ELEMENTS ON THE RAP DROP SOUTHWARD INTO NORTHERN ILLINOIS THIS MORNING AND HIGH RES GUIDANCE SUCH AS THE LOCAL ARW AND THE HOPWRF ENSEMBLE BRING LIGHT PRECIP SOUTH AS WELL. HAVE INCREASED THE COVERAGE OF FLURRIES IN THE FORECAST AND ADDED FREEZING DRIZZLE MENTION AS FORECAST PROFILES REMAIN BORDERLINE FOR EITHER...WHICH LINES UP WITH OBSERVATIONAL TRENDS. HAVE KEPT THE FREEZING DRIZZLE MENTION WEST OF CHICAGO FOR THE TIME BEING BASED ON EXTRAPOLATION OF ONGOING REPORTS. MTF && .PREV DISCUSSION... 350 AM CDT REST OF TODAY... THE PRIMARY CHANGES IN THE FORECAST WERE A QUICKER DIMINISHING OF ANY LIGHT SNOW CHANCES AS WELL AS TO BUMP UP TEMPERATURES NAMELY THIS MORNING. DEEP DRY AIR AND SUPPRESSION LOOK TO MOVE QUICKLY INTO THE AREA BY LATE MORNING BEHIND THIS SYSTEM. CONTINUING LOW- LEVEL CYCLOGENESIS OFF TO THE EAST WILL DRIVE COLD AIR ADVECTION INTO THE REGION...AND PROFILES WILL BE SUPPORTIVE OF KEEPING STRATOCU AND MAYBE SOME FLURRIES INTO EARLY TO MID AFTERNOON. TEMPERATURES ARE FAIRLY HOMOGENEOUS UP TO CENTRAL/SOUTHERN WI EARLY THIS MORNING...SO LOW-LEVEL THERMAL ADVECTION LOOKS TO BE NEUTRAL THROUGH DAYBREAK AND THEN SLIGHT COLD AIR ADVECTION THIS MORNING. TEMPERATURES SHOULD LEVEL OUT THIS AFTERNOON AS AT LEAST SOME MARCH SUNSHINE OFFSETS ANY COLD AIR ADVECTION. WITH NOT AS COLD OF AIR QUICKLY COMING INTO THE AREA...THE POSSIBILITY OF LAKE EFFECT SNOW SHOWERS INTO NORTHWEST INDIANA LOOKS QUITE SMALL...BUT POSSIBLY SOME CLOUDS GENERATING INTO LAKE AND PORTER COUNTIES THIS AFTERNOON. TONIGHT... HIGH PRESSURE WILL MOVE OVER THE REGION TONIGHT AND SET THE STAGE FOR A COLD NIGHT BY MID-MARCH STANDARDS. HIGH CLOUDS DO LOOK TO SPILL INTO THE WESTERN FORECAST AREA AS THE NIGHT PROGRESSES AS A SHEARED WEAK SHORTWAVE DROPS SOUTHWARD ON THE BACKSIDE OF THE DEVELOPING LONGWAVE TROUGH. BUT IT LOOKS TO BE A LITTLE TOO LATE TO STOP TEMPERATURES FROM DROPPING NICELY OVER FRESH SNOW COVER THIS EVE INTO EARLY OVERNIGHT. FORECAST TEMPERATURES WITH MODEST CONFIDENCE ARE SINGLE DIGITS IN OUTLYING AREAS TO 10 TO 15 IN THE CHICAGO METRO. THAT LINES UP WITH THE 850MB TEMPERATURES OF -12C TO -15C ACROSS THE FORECAST AREA BY TONIGHT...WHICH ARE WELL BELOW CLIMO. IF CLOUDS WERE TO MOVE IN QUICKER IT WOULD RESULT IN MINS POTENTIALLY QUITE A BIT WARMER. THURSDAY AND BEYOND... WHILE THE UPPER FLOW PATTERN BECOMES NORTHWEST AND REMAINS DECENTLY ACTIVE THROUGH THE REST OF THE FORECAST PERIOD...WE REMAIN ON THE ANTICYCLONIC SIDE. THUS WE LOOK TO FREQUENTLY MISS THE BEST FORCING AND DEEPER SATURATION OF EACH QUICK-MOVING SYSTEM. IT DOES MAKE FOR A CHALLENGE WITH TEMPERATURES...ESPECIALLY WEIGHING RECENT SNOW COVER AND OCCASIONALLY PASSING CLOUD COVER. DO MAINTAIN A SMALL CHANCE FOR LIGHT SNOW THURSDAY MORNING IN NORTHERN AREAS AS WARM AIR ADVECTION ALOFT MOVES IN BEHIND THE TROUGH. SATURATION LOOKS TO BE A PROBLEM...BUT THE ISENTROPIC ASCENT IS PRETTY STRONG AND SATURATION ON BOTH THE NAM AND GFS IS DEPICTED TO BE LOW ENOUGH FOR SOME LIGHT SNOW TO REACH THE GROUND...IF IT CAN MATERIALIZE. FRIDAY LOOKS MILD WITH TEMPERATURES POTENTIALLY PUSHING 50 DEGREES AS WEST SOUTHWEST LOW-LEVEL FLOW BRING A WARM SECTOR OF ONE OF THE QUICK-MOVING SYSTEMS INTO OUR AREA. HAVE GONE WITH AN GFS/EC BLEND FOR THE WEEKEND INTO EARLY NEXT WEEK. THE GFS IS CONSIDERABLY COLDER FOR SUNDAY AND SUNDAY NIGHT WITH A STRONG CANADIAN HIGH PASSING OVER THE AREA...WHILE THE EC FAVORS THIS FEATURE TO BE MUCH FURTHER NORTH AND WEAKER. MTF && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 12Z... * LIGHT SNOW ENDING BY 13Z. * BLOWING SNOW THIS MORNING. * MVFR CIGS THROUGH THIS AFTERNOON. * STRONG/GUSTY NORTHERLY WINDS THROUGH MID/LATE AFTERNOON. CMS //DISCUSSION...UPDATED 12Z... BACK EDGE OF LIGHT SNOW WILL BE MOVING EAST OF MDW/GYY BY 13Z. STILL THE POTENTIAL FOR SOME FLURRIES OR VERY LIGHT SNOW THROUGH MID MORNING BUT NOT EXPECTING ANY VIS/CIGS RESTRICTIONS. BLOWING SNOW/LOW DRIFTING SNOW WILL CONTINUE INTO THIS AFTERNOON. ONCE SNOW ENDS...MVFR CIGS WILL CONTINUE INTO THIS AFTERNOON THEN SCATTER OUT BY EVENING WITH SKC EXPECTED TONIGHT. STRONG/GUSTY NORTHERLY WINDS WILL CONTINUE THROUGH MUCH OF THE DAY WITH GUSTS AS HIGH AS 30KTS FOR THE NEXT FEW HOURS...THEN GUSTS WILL DIMINISH INTO THE MID/UPPER 20KT RANGE BY LATE MORNING... SLOWLY AND STEADILY DIMINISHING THROUGH AFTERNOON WITH GUSTS ENDING WITH SUNSET. WINDS WILL BECOME LIGHT AND VARIABLE OVERNIGHT AS A RIDGE OF HIGH PRESSURE MOVES ACROSS THE AREA. CMS //ORD AND MDW CONFIDENCE...UPDATED 12Z... * HIGH FOR SNOW END TIMING. * HIGH FOR CIG TRENDS. * HIGH FOR WINDS SPEEDS/GUSTS/DIRECTIONS. CMS //OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z... * THURSDAY NIGHT...DRY/VFR. * FRIDAY...DRY/VFR. GUSTY WESTERLY WINDS. * SATURDAY THROUGH SUNDAY...DRY/VFR. * TUESDAY...CHANCE OF RAIN/SNOW. MVFR POSSIBLE. && .MARINE... 210 PM CDT LOW PRESSURE OVER THE CENTRAL PLAINS WILL CONTINUE TO DEEPEN AS IT TRACKS EAST ACROSS SOUTHERN ILLINOIS TONIGHT AND INTO THE OHIO VALLEY WEDNESDAY. AS THE LOW TRACKS SOUTH AND THEN SOUTHEAST OF THE LAKE...HIGH PRESSURE WILL ALSO BUILD ACROSS THE UPPER GREAT LAKES REGION...SETTING UP STRONG NORTH WINDS. THE COMBINATION OF A STRONG GRADIENT AND STRONG COLD ADVECTION WILL LEAD TO WINDS QUICKLY INCREASING TO GALES BY LATE THIS EVENING. THE LATEST GUIDANCE HAS BEEN RELATIVELY CONSISTENT IN INDICATING THE POTENTIAL FOR HIGH END GALES BY LATE WEDNESDAY MORNING AND EARLY AFTERNOON...WITH THE STRONGEST GALES OVER THE SOUTHERN PORTIONS OF THE LAKE...INCLUDING THE NEARSHORE WATERS. BY WEDNESDAY EVENING...THE HIGH PRESSURE WILL BEGIN TO SPREAD ACROSS LAKE MICHIGAN ALLOWING WINDS TO SUBSIDE BELOW GALE FORCE. BY THURSDAY NIGHT...THE HIGH WILL PUSH TO THE SOUTHEAST OF THE LAKE AS A CLIPPER DROPS OUT OF NORTHERN ALBERTA AND SWINGS JUST NORTH OF THE UPPER GREAT LAKES ON FRIDAY. WITH THE SFC HIGH SAGGING OFF THE SERN COAST...A PERIOD OF SWLY WINDS WILL DEVELOP AHEAD OF AN APPROACHING COLD FRONT TRAILING FROM THE CLIPPER. ANTICIPATE A PERIOD OF BRISK SLY TO SWLY WINDS FOR THURSDAY NIGHT THROUGH FRIDAY...BUT MORE GALES ARE NOT EXPECTED AT THIS TIME. AS THE CLIPPER TURNS NEWD INTO QUEBEC...IT WILL DRAG A WEAK COLD FRONT DOWN THE LAKE WITH ANOTHER ARCTIC HIGH BUILDING IN BEHIND THE FRONT. 25-30KT NORTH WINDS WILL SET UP FOLLOWING THE FROPA FOR SATURDAY NIGHT AND SUNDAY...BUT AS THE HIGH SPREADS ACROSS THE GREAT LAKES SUNDAY NIGHT...WINDS SHOULD BECOME MORE LIGHT AND VARIABLE. KREIN && .LOT WATCHES/WARNINGS/ADVISORIES... IL...WINTER STORM WARNING...ILZ013-ILZ014-ILZ020-ILZ021-ILZ022-ILZ023 UNTIL 11 AM WEDNESDAY. WINTER WEATHER ADVISORY...ILZ006-ILZ011-ILZ012 UNTIL 7 AM WEDNESDAY. WINTER WEATHER ADVISORY...ILZ019-ILZ032-ILZ033-ILZ039 UNTIL 11 AM WEDNESDAY. IN...WINTER STORM WARNING...INZ001-INZ002 UNTIL 11 AM WEDNESDAY. WINTER WEATHER ADVISORY...INZ010-INZ011-INZ019 UNTIL 11 AM WEDNESDAY. LM...GALE WARNING...LMZ080-LMZ669-LMZ671-LMZ673-LMZ675-LMZ740-LMZ741- LMZ742-LMZ743-LMZ744-LMZ745-LMZ777-LMZ779-LMZ870-LMZ872- LMZ874-LMZ876-LMZ878 UNTIL 10 PM WEDNESDAY. GALE WARNING...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-LMZ567- LMZ868 UNTIL 7 PM WEDNESDAY. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
645 AM CDT WED MAR 12 2014 .DISCUSSION... 350 AM CDT HAVE MADE SOME ADJUSTMENTS TO HEADLINES...NAMELY TO BRING UP EXPIRATION TIMES...INCLUDING WARNING FOR THE CHICAGO AREA. ALSO DID DOWNGRADE THE WARNING IN A HANDFUL OF COUNTIES THAT EITHER 1. RECEIVED CONSIDERABLY LESS SNOWFALL THAN ORIGINALLY FORECAST OR 2. WILL HAVE AN EARLIER END TIME WITH LESS BLOWING SNOW THAN INITIALLY THOUGHT AND THUS IMPACTS AFTER SUNRISE WILL BE CONSIDERABLY LESS...SO DID NOT FEEL WARNING WAS ANY LONGER APPROPRIATE FOR THOSE AREAS. THE VERY WELL-DEFINED UPPER LOW IS ENTERING WESTERN IL AS OF 330 AM WITH FURTHER AMPLIFICATION OCCURRING AS NORTHERN STREAM SHORT WAVE FROM MN DIGS SOUTHEAST TOWARD/INTO THIS SYSTEM. THE DEFORMATION AREA SEEMS TO BE FOLLOWING SUIT...WITH INCREASED REFLECTIVITY SINCE 300 AM IN A SOUTHWEST TO NORTHEAST CORRIDOR ALIGNING WITH FRONTOGENESIS...INCLUDING OVER CHICAGO. HAVE HAD A COUPLE LIGHTNING STRIKES NEAR PONTIAC IN THE PAST COUPLE HOURS AND JUST PRIOR TO THAT SEVERAL REPORTS THROUGH SOCIAL MEDIA OF HEARING THUNDER. SO SOME EMBEDDED HEAVIER RATES ARE LIKELY WITHIN THIS AXIS GIVEN REFLECTIVITY AND JUST WHAT IS OCCURRING OUT THE WINDOW IN ROMEOVILLE...INCLUDING WITH LARGE FLAKES COMMON OF HIGH MIXING RATIO SCENARIOS. CONTINUE THE WARNING FOR THE CHICAGO METRO AREA AND FAR NORTHWEST INDIANA BUT MOVE UP THE EXPIRATION TIME TO 11 AM...AND IT COULD END UP BEING CANCELLED EVEN EARLIER IF BLOWING SNOW AND ATTENDANT IMPACTS ARE DETERMINED TO BE LESS. FURTHER TO THE SOUTHEAST...MAINLY SOUTH OF A PONTIAC TO RENSSELAER LINE...GREATER ELEVATED INSTABILITY IS PRESENT PER LOOK OF RADAR ECHOES AND RAP ANALYSIS. MUCH OF THIS AREA HOWEVER CHANGED OVER TO ALL SNOW ONLY AT 2-330 AM AND THUS ACCUMULATIONS LOOK LIMITED...WHICH WE KNEW WOULD COULD OCCUR. SOME OF THE HEAVIEST CONVECTION JUST MISSED OVERRIDING THIS AREA HAS NOW SKIRTED INTO NORTHERN INDIANA. SO FOR THAT REASON AND REPORTS RECEIVED THROUGH DISPATCH...HAVE DOWNGRADED THOSE SOUTHERN AREAS...AS BLOWING SNOW SHOULD BE QUITE LIMITED THIS MORNING. REST OF TODAY... THE PRIMARY CHANGES IN THE FORECAST WERE A QUICKER DIMINISHING OF ANY LIGHT SNOW CHANCES AS WELL AS TO BUMP UP TEMPERATURES NAMELY THIS MORNING. DEEP DRY AIR AND SUPPRESSION LOOK TO MOVE QUICKLY INTO THE AREA BY LATE MORNING BEHIND THIS SYSTEM. CONTINUING LOW- LEVEL CYCLOGENESIS OFF TO THE EAST WILL DRIVE COLD AIR ADVECTION INTO THE REGION...AND PROFILES WILL BE SUPPORTIVE OF KEEPING STRATOCU AND MAYBE SOME FLURRIES INTO EARLY TO MID AFTERNOON. TEMPERATURES ARE FAIRLY HOMOGENEOUS UP TO CENTRAL/SOUTHERN WI EARLY THIS MORNING...SO LOW-LEVEL THERMAL ADVECTION LOOKS TO BE NEUTRAL THROUGH DAYBREAK AND THEN SLIGHT COLD AIR ADVECTION THIS MORNING. TEMPERATURES SHOULD LEVEL OUT THIS AFTERNOON AS AT LEAST SOME MARCH SUNSHINE OFFSETS ANY COLD AIR ADVECTION. WITH NOT AS COLD OF AIR QUICKLY COMING INTO THE AREA...THE POSSIBILITY OF LAKE EFFECT SNOW SHOWERS INTO NORTHWEST INDIANA LOOKS QUITE SMALL...BUT POSSIBLY SOME CLOUDS GENERATING INTO LAKE AND PORTER COUNTIES THIS AFTERNOON. TONIGHT... HIGH PRESSURE WILL MOVE OVER THE REGION TONIGHT AND SET THE STAGE FOR A COLD NIGHT BY MID-MARCH STANDARDS. HIGH CLOUDS DO LOOK TO SPILL INTO THE WESTERN FORECAST AREA AS THE NIGHT PROGRESSES AS A SHEARED WEAK SHORTWAVE DROPS SOUTHWARD ON THE BACKSIDE OF THE DEVELOPING LONGWAVE TROUGH. BUT IT LOOKS TO BE A LITTLE TOO LATE TO STOP TEMPERATURES FROM DROPPING NICELY OVER FRESH SNOW COVER THIS EVE INTO EARLY OVERNIGHT. FORECAST TEMPERATURES WITH MODEST CONFIDENCE ARE SINGLE DIGITS IN OUTLYING AREAS TO 10 TO 15 IN THE CHICAGO METRO. THAT LINES UP WITH THE 850MB TEMPERATURES OF -12C TO -15C ACROSS THE FORECAST AREA BY TONIGHT...WHICH ARE WELL BELOW CLIMO. IF CLOUDS WERE TO MOVE IN QUICKER IT WOULD RESULT IN MINS POTENTIALLY QUITE A BIT WARMER. THURSDAY AND BEYOND... WHILE THE UPPER FLOW PATTERN BECOMES NORTHWEST AND REMAINS DECENTLY ACTIVE THROUGH THE REST OF THE FORECAST PERIOD...WE REMAIN ON THE ANTICYCLONIC SIDE. THUS WE LOOK TO FREQUENTLY MISS THE BEST FORCING AND DEEPER SATURATION OF EACH QUICK-MOVING SYSTEM. IT DOES MAKE FOR A CHALLENGE WITH TEMPERATURES...ESPECIALLY WEIGHING RECENT SNOW COVER AND OCCASIONALLY PASSING CLOUD COVER. DO MAINTAIN A SMALL CHANCE FOR LIGHT SNOW THURSDAY MORNING IN NORTHERN AREAS AS WARM AIR ADVECTION ALOFT MOVES IN BEHIND THE TROUGH. SATURATION LOOKS TO BE A PROBLEM...BUT THE ISENTROPIC ASCENT IS PRETTY STRONG AND SATURATION ON BOTH THE NAM AND GFS IS DEPICTED TO BE LOW ENOUGH FOR SOME LIGHT SNOW TO REACH THE GROUND...IF IT CAN MATERIALIZE. FRIDAY LOOKS MILD WITH TEMPERATURES POTENTIALLY PUSHING 50 DEGREES AS WEST SOUTHWEST LOW-LEVEL FLOW BRING A WARM SECTOR OF ONE OF THE QUICK-MOVING SYSTEMS INTO OUR AREA. HAVE GONE WITH AN GFS/EC BLEND FOR THE WEEKEND INTO EARLY NEXT WEEK. THE GFS IS CONSIDERABLY COLDER FOR SUNDAY AND SUNDAY NIGHT WITH A STRONG CANADIAN HIGH PASSING OVER THE AREA...WHILE THE EC FAVORS THIS FEATURE TO BE MUCH FURTHER NORTH AND WEAKER. MTF && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 12Z... * LIGHT SNOW ENDING BY 13Z. * BLOWING SNOW THIS MORNING. * MVFR CIGS THROUGH THIS AFTERNOON. * STRONG/GUSTY NORTHERLY WINDS THROUGH MID/LATE AFTERNOON. CMS //DISCUSSION...UPDATED 12Z... BACK EDGE OF LIGHT SNOW WILL BE MOVING EAST OF MDW/GYY BY 13Z. STILL THE POTENTIAL FOR SOME FLURRIES OR VERY LIGHT SNOW THROUGH MID MORNING BUT NOT EXPECTING ANY VIS/CIGS RESTRICTIONS. BLOWING SNOW/LOW DRIFTING SNOW WILL CONTINUE INTO THIS AFTERNOON. ONCE SNOW ENDS...MVFR CIGS WILL CONTINUE INTO THIS AFTERNOON THEN SCATTER OUT BY EVENING WITH SKC EXPECTED TONIGHT. STRONG/GUSTY NORTHERLY WINDS WILL CONTINUE THROUGH MUCH OF THE DAY WITH GUSTS AS HIGH AS 30KTS FOR THE NEXT FEW HOURS...THEN GUSTS WILL DIMINISH INTO THE MID/UPPER 20KT RANGE BY LATE MORNING... SLOWLY AND STEADILY DIMINISHING THROUGH AFTERNOON WITH GUSTS ENDING WITH SUNSET. WINDS WILL BECOME LIGHT AND VARIABLE OVERNIGHT AS A RIDGE OF HIGH PRESSURE MOVES ACROSS THE AREA. CMS //ORD AND MDW CONFIDENCE...UPDATED 12Z... * HIGH FOR SNOW END TIMING. * HIGH FOR CIG TRENDS. * HIGH FOR WINDS SPEEDS/GUSTS/DIRECTIONS. CMS //OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z... * THURSDAY NIGHT...DRY/VFR. * FRIDAY...DRY/VFR. GUSTY WESTERLY WINDS. * SATURDAY THROUGH SUNDAY...DRY/VFR. * TUESDAY...CHANCE OF RAIN/SNOW. MVFR POSSIBLE. && .MARINE... 210 PM CDT LOW PRESSURE OVER THE CENTRAL PLAINS WILL CONTINUE TO DEEPEN AS IT TRACKS EAST ACROSS SOUTHERN ILLINOIS TONIGHT AND INTO THE OHIO VALLEY WEDNESDAY. AS THE LOW TRACKS SOUTH AND THEN SOUTHEAST OF THE LAKE...HIGH PRESSURE WILL ALSO BUILD ACROSS THE UPPER GREAT LAKES REGION...SETTING UP STRONG NORTH WINDS. THE COMBINATION OF A STRONG GRADIENT AND STRONG COLD ADVECTION WILL LEAD TO WINDS QUICKLY INCREASING TO GALES BY LATE THIS EVENING. THE LATEST GUIDANCE HAS BEEN RELATIVELY CONSISTENT IN INDICATING THE POTENTIAL FOR HIGH END GALES BY LATE WEDNESDAY MORNING AND EARLY AFTERNOON...WITH THE STRONGEST GALES OVER THE SOUTHERN PORTIONS OF THE LAKE...INCLUDING THE NEARSHORE WATERS. BY WEDNESDAY EVENING...THE HIGH PRESSURE WILL BEGIN TO SPREAD ACROSS LAKE MICHIGAN ALLOWING WINDS TO SUBSIDE BELOW GALE FORCE. BY THURSDAY NIGHT...THE HIGH WILL PUSH TO THE SOUTHEAST OF THE LAKE AS A CLIPPER DROPS OUT OF NORTHERN ALBERTA AND SWINGS JUST NORTH OF THE UPPER GREAT LAKES ON FRIDAY. WITH THE SFC HIGH SAGGING OFF THE SERN COAST...A PERIOD OF SWLY WINDS WILL DEVELOP AHEAD OF AN APPROACHING COLD FRONT TRAILING FROM THE CLIPPER. ANTICIPATE A PERIOD OF BRISK SLY TO SWLY WINDS FOR THURSDAY NIGHT THROUGH FRIDAY...BUT MORE GALES ARE NOT EXPECTED AT THIS TIME. AS THE CLIPPER TURNS NEWD INTO QUEBEC...IT WILL DRAG A WEAK COLD FRONT DOWN THE LAKE WITH ANOTHER ARCTIC HIGH BUILDING IN BEHIND THE FRONT. 25-30KT NORTH WINDS WILL SET UP FOLLOWING THE FROPA FOR SATURDAY NIGHT AND SUNDAY...BUT AS THE HIGH SPREADS ACROSS THE GREAT LAKES SUNDAY NIGHT...WINDS SHOULD BECOME MORE LIGHT AND VARIABLE. KREIN && .LOT WATCHES/WARNINGS/ADVISORIES... IL...WINTER STORM WARNING...ILZ013-ILZ014-ILZ020-ILZ021-ILZ022-ILZ023 UNTIL 11 AM WEDNESDAY. WINTER WEATHER ADVISORY...ILZ006-ILZ011-ILZ012 UNTIL 7 AM WEDNESDAY. WINTER WEATHER ADVISORY...ILZ019-ILZ032-ILZ033-ILZ039 UNTIL 11 AM WEDNESDAY. IN...WINTER STORM WARNING...INZ001-INZ002 UNTIL 11 AM WEDNESDAY. WINTER WEATHER ADVISORY...INZ010-INZ011-INZ019 UNTIL 11 AM WEDNESDAY. LM...GALE WARNING...LMZ080-LMZ669-LMZ671-LMZ673-LMZ675-LMZ740-LMZ741- LMZ742-LMZ743-LMZ744-LMZ745-LMZ777-LMZ779-LMZ870-LMZ872- LMZ874-LMZ876-LMZ878 UNTIL 10 PM WEDNESDAY. GALE WARNING...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-LMZ567- LMZ868 UNTIL 7 PM WEDNESDAY. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
1055 AM EDT WED MAR 12 2014 .UPDATE... ISSUED AT 1055 AM EDT WED MAR 12 2014 14Z SFC ANALYSIS SHOWS A DEEP LOW PRESSURE AREA OFF TO OUR NORTHEAST WHILE ITS SHARP COLD FRONT IS NOW CUTTING INTO EAST KENTUCKY. THIS BOUNDARY SIGNALS THE DROPOFF IN THE TEMPERATURES AND ARRIVAL OF THE HIGHER WIND GUSTS...UP TO 45 MPH...ON WEST TO NORTHWEST WINDS. OVER EAST KENTUCKY THE SOUTHWEST WINDS AHEAD OF THE BOUNDARY HAVE MIXED THE COLDER VALLEYS OUT SO THAT MOST AREAS ARE NOW IN THE UPPER 50S AND LOWER 60S WHICH IS WHERE OUR HIGH TEMPS WILL END UP. DEWPOINTS HAVE SURGED AHEAD OF THE FRONT INTO THE MIDDLE AND UPPER 50S...AS WELL. THIS MAY BE GIVING JUST ENOUGH ENERGY TO GENERATE A RUMBLE OF THUNDER WITH THE FRONT. THEREAFTER...TEMPERATURES PLUMMET WITH A BIT OF A LULL IN THE STEADIER PCPN...THOUGH ANY LINGERING SHOWERS WILL CHANGE TO SNOW FROM NORTHWEST TO SOUTHEAST LATER THIS AFTERNOON... GENERALLY FROM 3 PM IN THE FAR NORTH TO 5 PM DOWN TO THE HAL ROGERS PARKWAY AND THE HIGHER TERRAIN IN THE FAR EAST. THE REST OF THE CWA SHOULD GO OVER TO SNOW OR BE COLD ENOUGH FOR ALL SNOW AROUND 6 PM. PER THE LATEST HRRR AND NAM12 THE SNOW SHOULD BE RATHER MEAGER THROUGH DARK BUT THEN KICK IN FOR SEVERAL HOURS MOST PLACES INTO MID EVENING BEFORE TAPERING OFF FROM WEST TO EAST. THE WINDS WILL KEEP THE SNOW BLOWING AROUND AND REDUCE VISIBILITY EVEN AS IT HAS TROUBLE ACCUMULATING ON THE STILL TEMPORARILY WARM ROADS. THIS WILL CHANGE WITH TIME...BUT MUCH OF THE SNOW WILL BE GONE BEFORE THE ROAD SFCS ARE COLD ENOUGH TO STICK. EVEN SO...WOULD NOT BE SURPRISED TO HEAR OF SLICK SPOTS AND LOW VISIBILITY ISSUES BETWEEN 7 AND 10 PM FOR MUCH OF THE AREA. THE SPS CURRENTLY HAS THIS ADDRESSED...BUT AN ADVISORY MAY BE WARRANTED IF WE SEE SIGNS OF BEEFIER SNOWS AND BETTER ACCUMULATIONS UPSTREAM. WILL CONTINUE TO MONITOR THIS. THE HIGHEST SNOW ACCUMULATIONS ARE EXPECTED OVER THE HIGHER TERRAIN IN THE FAR SOUTHEAST WITH UP TO 2 INCHES POSSIBLE ON THE PEAKS NEAR VIRGINA. AN ADVISORY THERE WOULD NOT BE A STRETCH AT THIS POINT...EITHER. WILL GIVE THE NEW GFS A GANDER BEFORE MAKING ANY FINAL DECISIONS...THOUGH. THE GRIDS HAVE BEEN UPDATED TO FINE TUNE THE FROPA...WINDS...AND CAA. THESE HAVE BEEN SENT TO THE NDFD AND WEB SERVERS. A ZFP UPDATE CAN BE ANTICIPATED ONCE THE FRONT IS THROUGH THE ENTIRE CWA IN AN HOUR OR SO TO CLEAR UP WORDING AND TIMING. UPDATE ISSUED AT 842 AM EDT WED MAR 12 2014 FRESHENED UP THE HOURLY TEMPERATURES...DEW POINTS...AND POPS ACCORDING TO THE LATEST TRENDS IN OBSERVATIONS AND RADAR. THE SURFACE COLD FRONT LOOKS TO BE ON OUR DOORSTEP JUST BEFORE 11 AM...WITH A DISTINCTIVE BREAK IN THE PRECIP BETWEEN SHOWERS AFFECTING OUR AREA RIGHT NOW AND THE FRONT. THERE IS ALSO ANOTHER BREAK IN THE ACTION BEHIND THE INITIAL COLD FRONT...BEFORE PRECIP FILLS IN ONCE AGAIN AT THE CUSP OF THE COLDER AIR. HAVE ATTEMPTED TO TIME ALL OF THIS A BIT BETTER FOR THE NEXT SEVERAL HOURS. IT DOES APPEAR THAT THE COLD AIR IS LAGGING JUST A TAD LATER. MOST OF THE STRONGER WIND GUSTS ARE OCCURRING ALONG AND BEHIND THE FRONT. UPDATES HAVE BEEN SENT. && .SHORT TERM...(TODAY THROUGH THURSDAY) ISSUED AT 344 AM EDT WED MAR 12 2014 THE LATEST SURFACE MAP FEATURES DEEPENING SURFACE LOW PRESSURE CURRENTLY CENTERED ACROSS SOUTHERN IL/IN. A SHARP COLD FRONT IS DRAPED FROM SOUTHEASTERN MO DOWN THROUGH EASTERN TX. HIGH PRESSURE EXTENDS FROM THE PACIFIC NORTHWEST DOWN ACROSS THE ROCKIES...SETTING UP A TIGHT PRESSURE GRADIENT ACROSS THE PLAINS. ALOFT...A WEAKENING SHORT WAVE TROUGH IS ROTATING OVER THE FLORIDA PANHANDLE. A DEEPER TROUGH IS MOVING INTO THE NORTHERN PLAINS/GREAT LAKES WITH A LEAD SHORT WAVE MOVING THROUGH MO/IL. EASTERN KENTUCKY REMAINS PLANTED IN THE WARM SECTOR...WITH MOST LOCATIONS REPORTING TEMPERATURES IN THE 50S AND LOW 60S...WHILE A FEW SHELTERED VALLEYS REMAIN DECOUPLED...REPORTING IN THE MID AND UPPER 40S. THE MODELS ARE IN GOOD AGREEMENT WITH THE SHORT TERM...WITH THE NORTHERN STREAM TROUGH AMPLIFYING ACROSS THE EASTERN CONUS THROUGH TONIGHT...AND ALLOWING THE SURFACE LOW TO CONTINUE TO INTENSIFY AS IT SLIDES ENE ALONG AND JUST NORTH OF THE OHIO RIVER TODAY...REACHING THE NORTHERN NEW ENGLAND COAST BY EARLY THURSDAY MORNING. THIS STRONG STORM SYSTEM WILL BRING MULTIPLE IMPACTS TO EASTERN KENTUCKY TODAY AND TONIGHT. WIDESPREAD SHOWERS...ALONG WITH AN ISOLATED THUNDERSTORM CAN BE EXPECTED TODAY. SURFACE WINDS WILL ALSO BECOME STRONG DURING THE DAY...FIRST OUT OF THE SOUTHWEST...AND THEN QUICKLY SHIFTING TO THE WEST AND NORTHWEST...AS THE COLD FRONT PLOWS THROUGH THE AREA BETWEEN 12 AND 4 PM. SUSTAINED SPEEDS RANGING FROM 15 TO 30 MPH...WITH GUSTS IN THE 35 TO 45 MPH RANGE STILL LOOK ON TARGET. AS COLDER AIR RUSHES IN BEHIND THE FRONT...RAIN SHOWERS WILL CHANGE OVER TO SNOW SHOWERS. THE MODELS HAVE TRENDED SOMEWHAT SLOWER WITH THE ARRIVAL OF THE COLDER AIR...PARTICULARLY THE NAM. HAVE ADJUSTED THE TIMING BACK A TAD...BUT STILL AHEAD OF THE MODELS...AS THEY TEND TO BE A LITTLE SLOW WITH THESE KINDS OF DYNAMIC SYSTEMS. AS SUCH...EXPECT THE CHANGEOVER CLOSER TO THE 2 TO 3 PM TIME FRAME IN THE BLUEGRASS...AND IN THE 5 TO 6 PM RANGE IN THE SOUTHEAST FOR MOST LOCATIONS. HAVE NOT ADJUSTED AMOUNTS MUCH FROM THE PREVIOUS FORECAST...WITH A HALF INCH OR LESS FOR VALLEYS...AND UP TO AN INCH FOR RIDGETOPS. WILL HAVE TO WATCH THE SOUTHEAST TERRAIN COUNTIES TONIGHT THOUGH...AS THE LATEST NAM IS A LITTLE BEEFIER WITH LIFT AND MOISTURE. FOR NOW...WILL CONTINUE WITH A SPECIAL WEATHER STATEMENT HIGHLIGHTING THE MULTIPLE IMPACTS. SNOW SHOWERS WILL GRADUALLY TAPER OFF FROM NORTHWEST TO SOUTHEAST TONIGHT...LINGERING LONGEST IN THE FAR SOUTHEAST. NORTHWEST WINDS WILL DIMINISH THROUGH THE EVENING...HOWEVER THE COMBINATION OF THE WIND AND TEMPERATURES FALLING INTO THE TEENS...WILL STILL ALLOW FOR SOME SINGLE DIGIT WIND CHILL READINGS LATE TONIGHT INTO EARLY THURSDAY MORNING. HIGH PRESSURE WILL MOVE IN FOR THURSDAY...GRADUALLY BRINGING ANY LINGERING SNOW FLURRIES TO AN END. HIGHS STILL LOOK TO NOT MAKE IT OUT OF THE 30S. .LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY) ISSUED AT 335 AM EDT WED MAR 12 2014 EXTENDED PERIOD WILL BE FAIRLY BENIGN COMPARED TO THE SHORT TERM. HOWEVER...CONFIDENCE IN MODELS IS FAIRLY LOW FROM 0Z SATURDAY ON...AS THEY ARE HAVING A VERY HARD TIME AGREEING ON UPPER LEVEL FLOW...AND AS A RESULT...SURFACE FEATURES TO IMPACT EASTERN KY. WILL RELY ON THE ALLBLEND SOLUTION FOR DAYS 4 THROUGH 7 WITH A GENERAL BLEND OF THE MODELS FOR THIS DISCUSSION. LUCKILY...0Z FRIDAY THROUGH 0Z SATURDAY IS THE ONE PERIOD WHERE SOME CONFIDENCE DOES EXISTS. THE LONGWAVE TROUGH WHICH CONTRIBUTED TO THE RETURN OF WINTER PRECIP AND TEMPS WILL BE EXITING FROM THE REGION...WITH PRESSURE HEIGHTS BUILDING THROUGHOUT THE NIGHT AND BECOMING MORE ZONAL DURING THE DAY FRIDAY. THIS TREND WILL LEAD TO SURFACE HIGH PRESSURE AND DRY...WARMING CONDITIONS AT THE SURFACE THURSDAY NIGHT THROUGH FRIDAY. WHILE HIGHS ON THURSDAY WILL ONLY BE IN THE LOW TO MID 30S...FRIDAY WILL INCREASE QUITE NICELY INTO THE MID AND UPPER 50S FOR HIGHS. MODELS ARE THEN POINTING AT A SHORTWAVE OVER THE SOUTHERN PLAINS BY 06Z SATURDAY. THIS SHORTWAVE WILL HAVE STARTED OFF AS A CLOSED LOW OVER ARIZONA AND NEW MEXICO FRIDAY...AND MOVED ONLY SLIGHTLY BY SATURDAY WHILE LOSING SUBSTANTIAL STRENGTH. MODELS ARE ALL IN AGREEMENT THAT THIS TROUGH WILL CONTINUE TO SLOWLY WEAKEN AS IT MAKES ITS WAY ENE TOWARDS THE OHIO RIVER VALLEY. HOWEVER...THIS IS ABOUT ALL THE AGREE ON. AT THE SURFACE...EXPECT THIS SHORTWAVE TO LEAD TO A SURFACE LOW PRESSURE SYSTEM...WITH SOME IMPACTS TO KENTUCKY AS IT PASSES THROUGH. HOWEVER...EVERY MODEL VARIES GREATLY ON THE EXTENT OF THE IMPACTS AND THE TIMING. THE GFS40 IS THE FASTEST SOLUTION...WITH A LINE OF PRECIP MOVING IN BETWEEN 6 AND 12Z SATURDAY...THE GEM IS ALMOST 24 HOURS LATER...AND THE ECMWF IS ANOTHER 6 HOURS AFTER THAT. AS A RESULT...LEANED ON THE ALLBLEND SOLUTION AS THE BEST COMPROMISE AT THIS POINT. MODELS CONTINUE TO DIVERGE IN SOLUTIONS FROM HERE ON OUT. DO EXPECT ANOTHER FEW SHORTWAVES TO IMPACT THE CWA THROUGH THE REST OF THE EXTENDED...BRINGING MORE CHANCES OF PRECIPITATION...BUT CONFIDENCE IS SO LOW ON WHEN AND WHERE ANYTHING WILL SET UP THAT WILL GO WITH ALLBLEND...AND THEN REDUCE ANY CHANCES THAT ARE WITHIN THE ALLBLEND DOWN TO SLIGHT SO AS NOT TO GIVE PREFERENCE OVER ONE MODEL OR ANOTHER. CHANCES WILL BE INCREASED AS MODELS START TO COME INTO BETTER AGREEMENT OVER THE NEXT FEW FORECAST CYCLES. AS FOR TEMPERATURES AND PRECIPITATION TYPE...SIMILAR PROBLEMS EXIST. HOWEVER...IF UPPER LEVEL HEIGHTS DO FALL...IT WILL NOT BE BY A SIGNIFICANT AMOUNT...SO EXPECT TEMPERATURES TO REMAIN RIGHT AROUND IF NOT SLIGHTLY BELOW NORMAL THROUGH THE REMAINDER OF THE EXTENDED. IF THIS HOLDS TRUE...PRECIP WILL FALL IN THE FORM OF RAIN DURING THE DAY AND OVERNIGHT...WITH THE EXCEPTION OF SUNDAY NIGHT...WHERE TEMPS COULD COOL OFF TO JUST BELOW FREEZING AND CAUSE A RAIN/SNOW MIX ACROSS THE AREA INSTEAD. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING) ISSUED AT 842 AM EDT WED MAR 12 2014 A STRENGTHENING AREA OF LOW PRESSURE WILL TRACK ACROSS NORTHERN KENTUCKY DURING THE DAY...ALLOWING FOR THE REDEVELOPMENT OF SHOWERS ALONG AND JUST BEHIND THE ASSOCIATED COLD FRONT. CEILINGS WILL DROP DOWN TO LOW MVFR/IFR BEHIND THE FRONT...WITH POCKETS OF IFR OCCURRING WITHIN ANY STRONGER SHOWERS. SOUTH TO SOUTHWEST WINDS WILL INCREASE DURING THE DAY WITH GUSTS AS STRONG AS 25 TO 30 KT POSSIBLE AHEAD OF THE FRONT. WINDS WILL SHIFT TO THE WEST AND NORTHWEST BETWEEN 15 AND 18Z...WITH WIND GUSTS INCREASING CLOSER TO THE 30 TO 35 KT RANGE. RAIN SHOWERS WILL CHANGE OVER TO SNOW SHOWERS FROM NORTHWEST TO SOUTHEAST BETWEEN 20 AND 00Z. CEILINGS WILL GRADUALLY IMPROVE TOWARDS DAWN FROM NORTHWEST TO SOUTHEAST. && .JKL WATCHES/WARNINGS/ADVISORIES... WIND ADVISORY UNTIL 10 PM EDT THIS EVENING FOR KYZ044-050>052- 058>060-068-069-079-080-083>088-104-106>120. && $$ UPDATE...GREIF SHORT TERM...GEOGERIAN LONG TERM...JMW AVIATION...GEOGERIAN
AREA FORECAST DISCUSSION...UPDATED
NWS GRAY ME
1041 AM EDT WED MAR 12 2014 .SYNOPSIS... LOW PRESSURE WILL MOVE NORTHEAST OUT OF THE OHIO VALLEY TODAY AND WILL RAPIDLY INTENSIFY AS IT MOVES OFF THE NEW ENGLAND COAST OVERNIGHT. LOW PRESSURE WILL CONTINUE NORTHEAST THROUGH THE MARITIMES ON THURSDAY. A RIDGE OF HIGH PRESSURE WILL BUILD IN FROM THE WEST THURSDAY NIGHT. HIGH PRESSURE WILL MOVE OFFSHORE ON FRIDAY AS A WARM FRONT LIFTS INTO THE REGION FROM THE SOUTHWEST. A COLD FRONT WILL APPROACH FROM THE WEST FRIDAY NIGHT AND SATURDAY AND WILL SLOWLY CROSS THE REGION SATURDAY NIGHT. HIGH PRESSURE WILL GRADUALLY BUILD IN FROM THE WEST SUNDAY THROUGH MONDAY. && .NEAR TERM /THROUGH TONIGHT/... UPDATE...VERY COMPLEX FORECAST TODAY AS LOW PRES RAMPS UP INVOF KPIT ATTM. MID LEVEL FNT IS REALLY STARTING TO STRENGTHEN...AS STRONG WAA DEVELOPS TO THE S OF THE LOW PRES TRACK...AND CAA PRESSES DOWN FROM THE N. ALONG THIS BOUNDARY SIGNIFICANT PCPN IS EXPECTED. LATEST TRENDS SHOW NO REASON TO DEVIATE FROM PREVIOUS SHIFT/S AXIS OF HEAVIEST QPF. CURRENT PCPN ACROSS MOST OF THE CWFA IS A BIT OF A KITCHEN SINK SCENARIO...AS LINGERING WARM LAYERS ARE RESULTING IN SLEET...FZRA...RNFL...AND SNFL. EXPECT THAT AS STRONGER LIFT MOVES OVERHEAD THAT THINGS WILL FLIP TO SNFL...EXCEPT FOR THE IMMEDIATE COAST. THEN AS MID LEVELS WARM THIS AFTERNOON...SNFL WILL TRANSITION BACK TO A MIX FOR CENTRAL AND SRN AREAS. ACROSS THE FAR N...IT IS IMPORTANT TO NOTE THAT COLD FNT IS ALREADY DROPPING INTO PARTS OF NRN NEW ENGLAND. TEMPS AND DEWPOINTS ACROSS NRN VT AND SRN QUEBEC ARE FALLING ATTM. HOW FAR THIS BOUNDARY CAN ADVANCE SWD AHEAD OF THE LOW PRES WILL DETERMINE JUST HOW FAR N THE RNFL WILL MAKE IT INTO NH ESPECIALLY. THOUGH MID LEVELS MAY WARM ABOVE FREEZING...CENTRAL NH SHOULD REMAIN BELOW FREEZING AT THE SURFACE...YIELDING MORE IN THE WAY OF SLEET THAN RA. PREVIOUSLY... VERY TRICKY AND LOW CONFIDENCE FORECAST CONTINUES FOR THE COASTAL PLAIN TODAY. MUCH OF THE 00Z GUIDANCE HAS WARMED FOR TODAY...BASICALLY CATCHING UP TO WHAT THE ECMWF HAS BEEN SHOWING FOR AWHILE NOW. THIS HAS RESULTED IN THE ADJUSTMENT OF THE TIMING OF SOME OF THE WARNINGS AND ADVISORIES. AS A RESULT OF THE COLUMN WARMING ACROSS SOUTHERN AREAS TODAY...THE MID LEVEL FRONTOGENETICAL ZONE WILL BE PUSHED NORTH. THE RESULT SHOULD BE A NORTHWARD PUSH OF THE MODERATE TO HEAVY PRECIPITATION INTO THE MOUNTAINS AND FOOTHILLS FOR MUCH OF THE DAY. IN FACT...THE LATEST HRRR AND RAP HAVE LITTLE IN THE WAY OF PRECIPITATION TODAY ACROSS SOUTHERNMOST PORTIONS OF NH AND ME THROUGH AT LEAST 21Z. THEREFORE...THE LIGHT NATURE OF THE PRECIPITATION COMBINED WITH A WARMING COLUMN SHOULD NOT ALLOW FOR WIDESPREAD HAZARDOUS WEATHER CONDITIONS THERE DURING MUCH OF THE DAY TODAY NEAR THE COAST. IN FACT...JUST A LIGHT TO OCCASIONALLY MODERATE RAIN MIXED WITH SNOW AND SLEET AT TIMES SEEMS TO BE THE MOST LIKELY SCENARIO ALONG COASTAL ME SOUTHWESTWARD TO MUCH OF SOUTHERN NH. CONSIDERED DOWNGRADING THE WARNINGS TO ADVISORIES IN THESE AREAS...BUT SINCE COLD AIR IS EXPECTED TO RAPIDLY MOVE IN TONIGHT RESULTING IN A HEAVY MIXED BAG OF SNOW...SLEET...AND FREEZING RAIN COMBINED WITH STRONG WINDS...FELT IS WAS BEST TO KEEP THE WARNINGS GOING. A FLASH FREEZE WILL BE POSSIBLE THIS EVENING AT LOCATIONS THAT HOLD ONTO ABOVE FREEZING TEMPS TODAY. WE/VE RADIATED DOWN TO AROUND FREEZING EARLY THIS WEDNESDAY MORNING...AND THIS SHOULD RESULT IN SOME FROZEN/FREEZING PRECIPITATION EARLY ON. MAY ADDRESS THIS WITH AN SPS DEPENDING ON HOW THE RADAR LOOKS IN A FEW HOURS. IN THE MOUNTAINS AND FOOTHILLS...EXPECT HEAVY SNOW TODAY...POSSIBLY MIXED WITH SLEET. IN THE TRANSITION AREA BETWEEN THE FOOTHILLS AND THE COASTAL PLAIN /EG...INTERIOR CUMBERLAND COUNTY ME/...EXPECT OSCILLATING PRECIPITATION TYPES MAKING FOR HAZARDOUS DRIVING CONDITIONS TODAY. A VERY CHANGEABLE SITUATION IS EXPECTED TODAY...AND THEREFORE FORECAST ADJUSTMENTS ARE LIKELY. && .SHORT TERM /THURSDAY THROUGH THURSDAY NIGHT/... AS STRONG LOW PRESSURE PULLS INTO THE GULF OF MAINE TONIGHT...LOW LEVEL COLD AIR SHOULD RACE SOUTHEASTWARD TOWARD THE COAST. THIS SHOULD CHANGE ANY RAIN OR RAIN/SLEET MIX TO A MIX OF SNOW...SLEET...AND FREEZING RAIN. CURRENTLY FORECASTING UP TO A QUARTER INCH OF ICE FOR THE COASTAL PLAIN TONIGHT BEFORE THE COLUMN COOLS ENOUGH TO SUPPORT ALL SNOW. WINDS ARE EXPECTED TO INCREASE THIS EVENING AND GUST UP TO 45 MPH. THEREFORE...AREAS THAT SEE A WET SNOW AND/OR FREEZING RAIN MAY HAVE TO DEAL WITH POWER OUTAGES AS THE NIGHT WEARS ON. THE SNOW SHOULD TAPER OFF THURSDAY MORNING AND END BY EARLY AFTERNOON...LEAVING VERY COLD AIR IN THE STORMS WAKE FOR THE BALANCE OF THE DAY. && .LONG TERM /FRIDAY THROUGH TUESDAY/... LOW PRESSURE WILL PULL AWAY THURSDAY NIGHT FOLLOWED BY A NARROW RIDGE OF HIGH PRESSURE. EXPECT ANY LINGERING SNOW SHOWERS TO QUICKLY COME TO AN END THURSDAY EVENING AND SKIES WILL CLEAR AS HIGH PRESSURE BUILDS IN FROM THE WEST. TEMPERATURES WILL ONCE AGAIN END UP WELL BELOW NORMAL WITH LOWS OF ZERO TO AROUND 10 BELOW IN THE NORTH AND 5 BELOW TO 5 ABOVE IN THE SOUTH. LOW PRESSURE CROSSING SOUTHERN CANADA FRIDAY WILL LIFT A WARM FRONT INTO THE REGION IN THE AFTERNOON. WILL SEE INCREASING CLOUDS WITH A CHANCE OF SNOW SHOWERS...MAINLY IN NORTHWEST ZONES DURING THE LATE MORNING AND AFTERNOON. HIGH TEMPS WILL RANGE THROUGH THE 20S NORTH AND IN THE LOWER TO MID 30S SOUTH. PRE-FRONTAL TROUGH WILL BRING A CHANCE SNOW SHOWERS IN THE NORTH AND RAIN SHOWERS OR MIXED PRECIP IN THE SOUTH FRIDAY NIGHT. NOT A LOT OF FORCING WITH THIS BOUNDARY SO NOT LOOKING FOR MUCH IN THE WAY OF QPF. TROUGH PUSHES OFFSHORE EARLY SATURDAY MORNING AND SKIES SHOULD BECOME PARTLY TO MOSTLY SUNNY. COLD FRONT APPROACHING FROM THE NORTHWEST WILL BRING MORE CLOUDS INTO NORTHWEST ZONES IN THE AFTERNOON. EXPECT HIGHS RANGING THROUGH THE 40S. COLD FRONT WILL SLOWLY CROSS THE REGION SATURDAY NIGHT WITH LITTLE IF ANY FANFARE. WILL SEE THICKENING CLOUDS AND A CHANCE OF SNOW SHOWERS IN THE MOUNTAINS AND JUST VARIABLE CLOUDINESS ELSEWHERE. TEMPERATURES BY SUNDAY MORNING WILL RANGE FROM THE TEENS NORTH TO THE LOWER TO MID 20S SOUTH. SUNDAY LOOKING BREEZY AND COOLER BEHIND THE FRONT AS HIGH PRESSURE BUILDING IN FROM THE WEST SETS UP A TIGHT NORTHWESTERLY GRADIENT ACROSS THE REGION. EXPECT CLOUDS TO HANG TOUGH IN THE CONNECTICUT VALLEY AND THE MOUNTAINS THROUGH THE DAY WITH A MIX OF SUN AND CLOUDS ELSEWHERE. HIGH PRESSURE WILL CONTINUE TO BUILD IN FROM THE WEST SUNDAY NIGHT THROUGH MONDAY. HIGH PRESSURE WILL GRADUALLY SLIP OFFSHORE SOUTH OF NEW ENGLAND MONDAY NIGHT AS A WEAK WARM FRONT LIFTS NORTH INTO SOUTHERN CANADA NORTHWEST OF THE FORECAST AREA. WILL SEE INCREASING CLOUDS OVERNIGHT AND POSSIBLY A FEW SNOW SHOWERS ON TUESDAY AS WEAK OVER-RUNNING BRUSHES NORTHWEST ZONES. && .AVIATION /15Z WEDNESDAY THROUGH SUNDAY/... SHORT TERM...VFR CONDITIONS WILL DETERIORATE TO IFR OR LOWER BY THIS AFTERNOON IN SNOW OR MIXED PRECIPITATION. LIFR CONDITIONS ARE EXPECTED THROUGH TONIGHT INTO THURSDAY MORNING. WIND GUSTS UP TO 40 KT ARE EXPECTED TONIGHT WHICH WILL RESULT IN MECHANICAL TURBULENCE. LONG TERM...VFR THURSDAY NIGHT THROUGH SUNDAY. && .MARINE... SHORT TERM...GALES THIS AFTERNOON THROUGH THURSDAY IN ASSOCIATION WITH COASTAL STORM. LONG TERM...SCAS LIKELY THURSDAY NIGHT AND FRIDAY NIGHT. GALES POSSIBLE SUNDAY NIGHT. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...WINTER STORM WARNING UNTIL NOON EDT THURSDAY FOR MEZ007>009- 012>014. WINTER STORM WARNING UNTIL NOON EDT THURSDAY FOR MEZ018>022. WINTER STORM WARNING FROM 6 PM THIS EVENING TO NOON EDT THURSDAY FOR MEZ024>028. WINTER WEATHER ADVISORY FROM 6 PM THIS EVENING TO NOON EDT THURSDAY FOR MEZ023. NH...WINTER STORM WARNING UNTIL NOON EDT THURSDAY FOR NHZ001>007- 009. WINTER STORM WARNING FROM 6 PM THIS EVENING TO NOON EDT THURSDAY FOR NHZ008-010. WINTER WEATHER ADVISORY FROM 6 PM THIS EVENING TO NOON EDT THURSDAY FOR NHZ013-014. MARINE...GALE WARNING FROM 4 PM THIS AFTERNOON TO 8 PM EDT THURSDAY FOR ANZ150>154. && $$ NEAR TERM...LEGRO
AREA FORECAST DISCUSSION...CORRECTED
NWS GRAY ME
945 AM EDT WED MAR 12 2014 .SYNOPSIS... LOW PRESSURE WILL MOVE NORTHEAST OUT OF THE OHIO VALLEY TODAY AND WILL RAPIDLY INTENSIFY AS IT MOVES OFF THE NEW ENGLAND COAST OVERNIGHT. LOW PRESSURE WILL CONTINUE NORTHEAST THROUGH THE MARITIMES ON THURSDAY. A RIDGE OF HIGH PRESSURE WILL BUILD IN FROM THE WEST THURSDAY NIGHT. HIGH PRESSURE WILL MOVE OFFSHORE ON FRIDAY AS A WARM FRONT LIFTS INTO THE REGION FROM THE SOUTHWEST. A COLD FRONT WILL APPROACH FROM THE WEST FRIDAY NIGHT AND SATURDAY AND WILL SLOWLY CROSS THE REGION SATURDAY NIGHT. HIGH PRESSURE WILL GRADUALLY BUILD IN FROM THE WEST SUNDAY THROUGH MONDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... 7 AM UPDATE...NO SIGNIFICANT CHANGES TO THE GOING FORECAST. JUST A FEW MINOR ADJUSTMENTS BASED ON LATEST TRENDS IN OBSERVATIONAL DATA. THINGS SEEM TO BE GOING AS PLANNED AT THE MOMENT. HOWEVER...ITS A VERY CHANGEABLE SITUATION TODAY SOUTH OF THE MOUNTAINS...SO STAY TUNED FOR FORECAST UPDATES. PREVIOUSLY... VERY TRICKY AND LOW CONFIDENCE FORECAST CONTINUES FOR THE COASTAL PLAIN TODAY. MUCH OF THE 00Z GUIDANCE HAS WARMED FOR TODAY...BASICALLY CATCHING UP TO WHAT THE ECMWF HAS BEEN SHOWING FOR AWHILE NOW. THIS HAS RESULTED IN THE ADJUSTMENT OF THE TIMING OF SOME OF THE WARNINGS AND ADVISORIES. AS A RESULT OF THE COLUMN WARMING ACROSS SOUTHERN AREAS TODAY...THE MID LEVEL FRONTOGENETICAL ZONE WILL BE PUSHED NORTH. THE RESULT SHOULD BE A NORTHWARD PUSH OF THE MODERATE TO HEAVY PRECIPITATION INTO THE MOUNTAINS AND FOOTHILLS FOR MUCH OF THE DAY. IN FACT...THE LATEST HRRR AND RAP HAVE LITTLE IN THE WAY OF PRECIPITATION TODAY ACROSS SOUTHERNMOST PORTIONS OF NH AND ME THROUGH AT LEAST 21Z. THEREFORE...THE LIGHT NATURE OF THE PRECIPITATION COMBINED WITH A WARMING COLUMN SHOULD NOT ALLOW FOR WIDESPREAD HAZARDOUS WEATHER CONDITIONS THERE DURING MUCH OF THE DAY TODAY NEAR THE COAST. IN FACT...JUST A LIGHT TO OCCASIONALLY MODERATE RAIN MIXED WITH SNOW AND SLEET AT TIMES SEEMS TO BE THE MOST LIKELY SCENARIO ALONG COASTAL ME SOUTHWESTWARD TO MUCH OF SOUTHERN NH. CONSIDERED DOWNGRADING THE WARNINGS TO ADVISORIES IN THESE AREAS...BUT SINCE COLD AIR IS EXPECTED TO RAPIDLY MOVE IN TONIGHT RESULTING IN A HEAVY MIXED BAG OF SNOW...SLEET...AND FREEZING RAIN COMBINED WITH STRONG WINDS...FELT IS WAS BEST TO KEEP THE WARNINGS GOING. A FLASH FREEZE WILL BE POSSIBLE THIS EVENING AT LOCATIONS THAT HOLD ONTO ABOVE FREEZING TEMPS TODAY. WE/VE RADIATED DOWN TO AROUND FREEZING EARLY THIS WEDNESDAY MORNING...AND THIS SHOULD RESULT IN SOME FROZEN/FREEZING PRECIPITATION EARLY ON. MAY ADDRESS THIS WITH AN SPS DEPENDING ON HOW THE RADAR LOOKS IN A FEW HOURS. IN THE MOUNTAINS AND FOOTHILLS...EXPECT HEAVY SNOW TODAY...POSSIBLY MIXED WITH SLEET. IN THE TRANSITION AREA BETWEEN THE FOOTHILLS AND THE COASTAL PLAIN /EG...INTERIOR CUMBERLAND COUNTY ME/...EXPECT OSCILLATING PRECIPITATION TYPES MAKING FOR HAZARDOUS DRIVING CONDITIONS TODAY. A VERY CHANGEABLE SITUATION IS EXPECTED TODAY...AND THEREFORE FORECAST ADJUSTMENTS ARE LIKELY. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/... AS STRONG LOW PRESSURE PULLS INTO THE GULF OF MAINE TONIGHT...LOW LEVEL COLD AIR SHOULD RACE SOUTHEASTWARD TOWARD THE COAST. THIS SHOULD CHANGE ANY RAIN OR RAIN/SLEET MIX TO A MIX OF SNOW...SLEET...AND FREEZING RAIN. CURRENTLY FORECASTING UP TO A QUARTER INCH OF ICE FOR THE COASTAL PLAIN TONIGHT BEFORE THE COLUMN COOLS ENOUGH TO SUPPORT ALL SNOW. WINDS ARE EXPECTED TO INCREASE THIS EVENING AND GUST UP TO 45 MPH. THEREFORE...AREAS THAT SEE A WET SNOW AND/OR FREEZING RAIN MAY HAVE TO DEAL WITH POWER OUTAGES AS THE NIGHT WEARS ON. THE SNOW SHOULD TAPER OFF THURSDAY MORNING AND END BY EARLY AFTERNOON...LEAVING VERY COLD AIR IN THE STORMS WAKE FOR THE BALANCE OF THE DAY. && .LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/... LOW PRESSURE WILL PULL AWAY THURSDAY NIGHT FOLLOWED BY A NARROW RIDGE OF HIGH PRESSURE. EXPECT ANY LINGERING SNOW SHOWERS TO QUICKLY COME TO AN END THURSDAY EVENING AND SKIES WILL CLEAR AS HIGH PRESSURE BUILDS IN FROM THE WEST. TEMPERATURES WILL ONCE AGAIN END UP WELL BELOW NORMAL WITH LOWS OF ZERO TO AROUND 10 BELOW IN THE NORTH AND 5 BELOW TO 5 ABOVE IN THE SOUTH. LOW PRESSURE CROSSING SOUTHERN CANADA FRIDAY WILL LIFT A WARM FRONT INTO THE REGION IN THE AFTERNOON. WILL SEE INCREASING CLOUDS WITH A CHANCE OF SNOW SHOWERS...MAINLY IN NORTHWEST ZONES DURING THE LATE MORNING AND AFTERNOON. HIGH TEMPS WILL RANGE THROUGH THE 20S NORTH AND IN THE LOWER TO MID 30S SOUTH. PRE-FRONTAL TROUGH WILL BRING A CHANCE SNOW SHOWERS IN THE NORTH AND RAIN SHOWERS OR MIXED PRECIP IN THE SOUTH FRIDAY NIGHT. NOT A LOT OF FORCING WITH THIS BOUNDARY SO NOT LOOKING FOR MUCH IN THE WAY OF QPF. TROUGH PUSHES OFFSHORE EARLY SATURDAY MORNING AND SKIES SHOULD BECOME PARTLY TO MOSTLY SUNNY. COLD FRONT APPROACHING FROM THE NORTHWEST WILL BRING MORE CLOUDS INTO NORTHWEST ZONES IN THE AFTERNOON. EXPECT HIGHS RANGING THROUGH THE 40S. COLD FRONT WILL SLOWLY CROSS THE REGION SATURDAY NIGHT WITH LITTLE IF ANY FANFARE. WILL SEE THICKENING CLOUDS AND A CHANCE OF SNOW SHOWERS IN THE MOUNTAINS AND JUST VARIABLE CLOUDINESS ELSEWHERE. TEMPERATURES BY SUNDAY MORNING WILL RANGE FROM THE TEENS NORTH TO THE LOWER TO MID 20S SOUTH. SUNDAY LOOKING BREEZY AND COOLER BEHIND THE FRONT AS HIGH PRESSURE BUILDING IN FROM THE WEST SETS UP A TIGHT NORTHWESTERLY GRADIENT ACROSS THE REGION. EXPECT CLOUDS TO HANG TOUGH IN THE CONNECTICUT VALLEY AND THE MOUNTAINS THROUGH THE DAY WITH A MIX OF SUN AND CLOUDS ELSEWHERE. HIGH PRESSURE WILL CONTINUE TO BUILD IN FROM THE WEST SUNDAY NIGHT THROUGH MONDAY. HIGH PRESSURE WILL GRADUALLY SLIP OFFSHORE SOUTH OF NEW ENGLAND MONDAY NIGHT AS A WEAK WARM FRONT LIFTS NORTH INTO SOUTHERN CANADA NORTHWEST OF THE FORECAST AREA. WILL SEE INCREASING CLOUDS OVERNIGHT AND POSSIBLY A FEW SNOW SHOWERS ON TUESDAY AS WEAK OVER-RUNNING BRUSHES NORTHWEST ZONES. && .AVIATION /07Z WEDNESDAY THROUGH SUNDAY/... SHORT TERM...VFR CONDITIONS WILL DETERIORATE TO IFR OR LOWER BY THIS AFTERNOON IN SNOW OR MIXED PRECIPITATION. LIFR CONDITIONS ARE EXPECTED THROUGH TONIGHT INTO THURSDAY MORNING. WIND GUSTS UP TO 40 KT ARE EXPECTED TONIGHT WHICH WILL RESULT IN MECHANICAL TURBULENCE. LONG TERM...VFR THURSDAY NIGHT THROUGH SUNDAY. && .MARINE... SHORT TERM...GALES THIS AFTERNOON THROUGH THURSDAY IN ASSOCIATION WITH COASTAL STORM. LONG TERM...SCAS LIKELY THURSDAY NIGHT AND FRIDAY NIGHT. GALES POSSIBLE SUNDAY NIGHT. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...WINTER STORM WARNING FROM 8 AM THIS MORNING TO NOON EDT THURSDAY FOR MEZ007>009-012>014. WINTER STORM WARNING FROM 11 AM THIS MORNING TO NOON EDT THURSDAY FOR MEZ018>022. WINTER STORM WARNING FROM 6 PM THIS EVENING TO NOON EDT THURSDAY FOR MEZ024>028. WINTER WEATHER ADVISORY FROM 6 PM THIS EVENING TO NOON EDT THURSDAY FOR MEZ023. NH...WINTER STORM WARNING FROM 8 AM THIS MORNING TO NOON EDT THURSDAY FOR NHZ001>007-009. WINTER STORM WARNING FROM 6 PM THIS EVENING TO NOON EDT THURSDAY FOR NHZ008-010. WINTER WEATHER ADVISORY FROM 6 PM THIS EVENING TO NOON EDT THURSDAY FOR NHZ013-014. MARINE...GALE WARNING FROM 4 PM THIS AFTERNOON TO 8 PM EDT THURSDAY FOR ANZ150>154. && $$ NEAR/SHORT TERM...MLE
AREA FORECAST DISCUSSION
NWS GRAY ME
710 AM EDT WED MAR 12 2014 .SYNOPSIS... LOW PRESSURE WILL MOVE NORTHEAST OUT OF THE OHIO VALLEY TODAY AND WILL RAPIDLY INTENSIFY AS IT MOVES OFF THE NEW ENGLAND COAST OVERNIGHT. LOW PRESSURE WILL CONTINUE NORTHEAST THROUGH THE MARITIMES ON THURSDAY. A RIDGE OF HIGH PRESSURE WILL BUILD IN FROM THE WEST THURSDAY NIGHT. HIGH PRESSURE WILL MOVE OFFSHORE ON FRIDAY AS A WARM FRONT LIFTS INTO THE REGION FROM THE SOUTHWEST. A COLD FRONT WILL APPROACH FROM THE WEST FRIDAY NIGHT AND SATURDAY AND WILL SLOWLY CROSS THE REGION SATURDAY NIGHT. HIGH PRESSURE WILL GRADUALLY BUILD IN FROM THE WEST SUNDAY THROUGH MONDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... 7 AM UPDATE...NO SIGNIFICANT CHANGES TO THE GOING FORECAST. JUST A FEW MINOR ADJUSTMENTS BASED ON LATEST TRENDS IN OBSERVATIONAL DATA. THINGS SEEM TO BE GOING AS PLANNED AT THE MOMENT. HOWEVER...ITS A VERY CHANGABLE SITUATION TODAY SOUTH OF THE MOUNTAINS...SO STAY TUNED FOR FORECAST UPDATES. PREVIOUSLY... VERY TRICKY AND LOW CONFIDENCE FORECAST CONTINUES FOR THE COASTAL PLAIN TODAY. MUCH OF THE 00Z GUIDANCE HAS WARMED FOR TODAY...BASICALLY CATCHING UP TO WHAT THE ECMWF HAS BEEN SHOWING FOR AWHILE NOW. THIS HAS RESULTED IN THE ADJUSTMENT OF THE TIMING OF SOME OF THE WARNINGS AND ADVISORIES. AS A RESULT OF THE COLUMN WARNING ACROSS SOUTHERN AREAS TODAY...THE MID LEVEL FRONTOGENETICAL ZONE WILL BE PUSHED NORTH. THE RESULT SHOULD BE A NORTHWARD PUSH OF THE MODERATE TO HEAVY PRECIPITATION INTO THE MOUNTAINS AND FOOTHILLS FOR MUCH OF THE DAY. IN FACT...THE LATEST HRRR AND RAP HAVE LITTLE IN THE WAY OF PRECIPITATION TODAY ACROSS SOUTHERNMOST PORTIONS OF NH AND ME THROUGH AT LEAST 21Z. THEREFORE...THE LIGHT NATURE OF THE PRECIPITATION COMBINED WITH A WARMING COLUMN SHOULD NOT ALLOW FOR WIDESPREAD HAZARDOUS WEATHER CONDITIONS THERE DURING MUCH OF THE DAY TODAY NEAR THE COAST. IN FACT...JUST A LIGHT TO OCCASIONALLY MODERATE RAIN MIXED WITH SNOW AND SLEET AT TIMES SEEMS TO BE THE MOST LIKELY SCENARIO ALONG COASTAL ME SOUTHWESTWARD TO MUCH OF SOUTHERN NH. CONSIDERED DOWNGRADING THE WARNINGS TO ADVISORIES IN THESE AREAS...BUT SINCE COLD AIR IS EXPECTED TO RAPIDLY MOVE IN TONIGHT RESULTING IN A HEAVY MIXED BAG OF SNOW...SLEET...AND FREEZING RAIN COMBINED WITH STRONG WINDS...FELT IS WAS BEST TO KEEP THE WARNINGS GOING. A FLASH FREEZE WILL BE POSSIBLE THIS EVENING AT LOCATIONS THAT HOLD ONTO ABOVE FREEZING TEMPS TODAY. WE/VE RADIATED DOWN TO AROUND FREEZING EARLY THIS WEDNESDAY MORNING...AND THIS SHOULD RESULT IN SOME FROZEN/FREEZING PRECIPITATION EARLY ON. MAY ADDRESS THIS WITH AN SPS DEPENDING ON HOW THE RADAR LOOKS IN A FEW HOURS. IN THE MOUNTAINS AND FOOTHILLS...EXPECT HEAVY SNOW TODAY...POSSIBLY MIXED WITH SLEET. IN THE TRANSITION AREA BETWEEN THE FOOTHILLS AND THE COASTAL PLAIN /EG...INTERIOR CUMBERLAND COUNTY ME/...EXPECT OSCILLATING PRECIPITATION TYPES MAKING FOR HAZARDOUS DRIVING CONDITIONS TODAY. A VERY CHANGEABLE SITUATION IS EXPECTED TODAY...AND THEREFORE FORECAST ADJUSTMENTS ARE LIKELY. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/... AS STRONG LOW PRESSURE PULLS INTO THE GULF OF MAINE TONIGHT...LOW LEVEL COLD AIR SHOULD RACE SOUTHEASTWARD TOWARD THE COAST. THIS SHOULD CHANGE ANY RAIN OR RAIN/SLEET MIX TO A MIX OF SNOW...SLEET...AND FREEZING RAIN. CURRENTLY FORECASTING UP TO A QUARTER INCH OF ICE FOR THE COASTAL PLAIN TONIGHT BEFORE THE COLUMN COOLS ENOUGH TO SUPPORT ALL SNOW. WINDS ARE EXPECTED TO INCREASE THIS EVENING AND GUST UP TO 45 MPH. THEREFORE...AREAS THAT SEE A WET SNOW AND/OR FREEZING RAIN MAY HAVE TO DEAL WITH POWER OUTAGES AS THE NIGHT WEARS ON. THD SNOW SHOULD TAPER OFF THURSDAY MORNING AND END BY EARLY AFTERNOON...LEAVING VERY COLD AIR IN THE STORMS WAKE FOR THE BALANCE OF THE DAY. && .LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/... LOW PRESSURE WILL PULL AWAY THURSDAY NIGHT FOLLOWED BY A NARROW RIDGE OF HIGH PRESSURE. EXPECT ANY LINGERING SNOW SHOWERS TO QUICKLY COME TO AN END THURSDAY EVENING AND SKIES WILL CLEAR AS HIGH PRESSURE BUILDS IN FROM THE WEST. TEMPERATURES WILL ONCE AGAIN END UP WELL BELOW NORMAL WITH LOWS OF ZERO TO AROUND 10 BELOW IN THE NORTH AND 5 BELOW TO 5 ABOVE IN THE SOUTH. LOW PRESSURE CROSSING SOUTHERN CANADA FRIDAY WILL LIFT A WARM FRONT INTO THE REGION IN THE AFTERNOON. WILL SEE INCREASING CLOUDS WITH A CHANCE OF SNOW SHOWERS...MAINLY IN NORTHWEST ZONES DURING THE LATE MORNING AND AFTERNOON. HIGH TEMPS WILL RANGE THROUGH THE 20S NORTH AND IN THE LOWER TO MID 30S SOUTH. PRE-FRONTAL TROUGH WILL BRING A CHANCE SNOW SHOWERS IN THE NORTH AND RAIN SHOWERS OR MIXED PRECIP IN THE SOUTH FRIDAY NIGHT. NOT A LOT FORCING WITH THIS BOUNDARY SO NOT LOOKING FOR MUCH IN THE WAY OF QPF. TROUGH PUSHES OFFSHORE EARLY SATURDAY MORNING AND SKIES SHOULD BECOME PARTLY TO MOSTLY SUNNY. COLD FRONT APPROACHING FROM THE NORTHWEST WILL BRING MORE CLOUDS INTO NORTHWEST ZONES IN THE AFTERNOON. EXPECT HIGHS RANGING THROUGH THE 40S. COLD FRONT WILL SLOWLY CROSS THE REGION SATURDAY NIGHT WITH LITTLE IF ANY FANFARE. WILL SEE THICKENING CLOUDS AND A CHANCE OF SNOW SHOWERS IN THE MOUNTAINS AND JUST VARIABLE CLOUDINESS ELSEWHERE. TEMPERATURES BY SUNDAY MORNING WILL RANGE FROM THE TEENS NORTH TO THE LOWER TO MID 20S SOUTH. SUNDAY LOOKING BREEZY AND COOLER BEHIND THE FRONT AS HIGH PRESSURE BUILDING IN FROM THE WEST SETS UP A TIGHT NORTHWESTERLY GRADIENT ACROSS THE REGION. EXPECT CLOUDS TO HANG TOUGH IN THE CONNECTICUT VALLEY AND THE MOUNTAINS THROUGH THE DAY WITH A MIX OF SUN AND CLOUDS ELSEWHERE. HIGH PRESSURE WILL CONTINUE TO BUILD IN FROM THE WEST SUNDAY NIGHT THROUGH MONDAY. HIGH PRESSURE WILL GRADUALLY SLIP OFFSHORE SOUTH OF NEW ENGLAND MONDAY NIGHT AS A WEAK WARM FRONT LIFTS NORTH INTO SOUTHERN CANADA NORTHWEST OF THE FORECAST AREA. WILL SEE INCREASING CLOUDS OVERNIGHT AND POSSIBLY A FEW SNOW SHOWERS ON TUESDAY AS WEAK OVER-RUNNING BRUSHES NORTHWEST ZONES. && .AVIATION /07Z WEDNESDAY THROUGH SUNDAY/... SHORT TERM...VFR CONDITIONS WILL DETERIORATE TO IFR OR LOWER BY THIS AFTERNOON IN SNOW OR MIXED PRECIPITATION. LIFR CONDITIONS ARE EXPECTED THROUGH TONIGHT INTO THURSDAY MORNING. WIND GUSTS UP TO 40 KT ARE EXPECTED TONIGHT WHICH WILL RESULT IN MECHANICAL TURBULENCE. LONG TERM...VFR THURSDAY NIGHT THROUGH SUNDAY. && .MARINE... SHORT TERM...GALES THIS AFTERNOON THROUGH THURSDAY IN ASSOCIATION WITH COASTAL STORM. LONG TERM...SCA`S LIKELY THURSDAY NIGHT AND FRIDAY NIGHT. GALES POSSIBLE SUNDAY NIGHT. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...WINTER STORM WARNING FROM 8 AM THIS MORNING TO NOON EDT THURSDAY FOR MEZ007>009-012>014. WINTER STORM WARNING FROM 11 AM THIS MORNING TO NOON EDT THURSDAY FOR MEZ018>022. WINTER STORM WARNING FROM 6 PM THIS EVENING TO NOON EDT THURSDAY FOR MEZ024>028. WINTER WEATHER ADVISORY FROM 6 PM THIS EVENING TO NOON EDT THURSDAY FOR MEZ023. NH...WINTER STORM WARNING FROM 8 AM THIS MORNING TO NOON EDT THURSDAY FOR NHZ001>007-009. WINTER STORM WARNING FROM 6 PM THIS EVENING TO NOON EDT THURSDAY FOR NHZ008-010. WINTER WEATHER ADVISORY FROM 6 PM THIS EVENING TO NOON EDT THURSDAY FOR NHZ013-014. MARINE...GALE WARNING FROM 4 PM THIS AFTERNOON TO 8 PM EDT THURSDAY FOR ANZ150>154. && $$ NEAR/SHORT TERM...MLE
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1138 AM EDT WED MAR 12 2014 LATEST UPDATE... UPDATE .SYNOPSIS... ISSUED AT 329 AM EDT WED MAR 12 2014 SNOW FALLING ACROSS THE SOUTHERN TWO THIRDS OF THE AREA THIS MORNING WILL GRADUALLY END THIS MORNING AND INTO EARLY THIS AFTERNOON FROM NW TO SE. HIGHEST SNOW ACCUMULATIONS WILL BE FOUND SOUTH OF I-69. SOME BLOWING AND DRIFTING SNOW WILL BE POSSIBLE AS WIND INCREASE THIS MORNING. SNOW AND CLOUDS WILL CLEAR OUT BY TONIGHT...ALLOWING FOR A RECORD COLD NIGHT FOR THE AREA. AFTER ANOTHER COLD DAY ON THURSDAY...TEMPERATURES WILL WARM BACK UP FOR FRIDAY WITH A SMALL CHANCE OF RAIN UP NORTH IN THE AFTERNOON. COLDER AIR AND A CHANCE FOR SNOW SHOWERS WILL MOVE BACK IN FOR SATURDAY. && .UPDATE... ISSUED AT 1138 AM EDT WED MAR 12 2014 I AM PLANNING ON DROPPING THE HEADLINES FOR ALL BUT JACKSON AND INGHAM COUNTIES BY NOON AS THE SNOW HAS ENDED OR NEARLY ENDED IN ALL OTHER COUNTIES. LOOKING AT WEB CAMS AROUND THOSE COUNTIES THE ROADS SEEM EITHER JUST WET AND I SEE NO SIGNIFICANT BLOWING SNOW ISSUES EITHER. THE HEADLINES IN JACKSON AND INGHAM COUNTIES SHOULD BE DONE BY 2 PM (ONE HOUR EARLY). UPDATE ISSUED AT 942 AM EDT WED MAR 12 2014 GREATEST SNOWFALL REPORTS SO FAR HAVE RANGED FROM 6 TO 7.5 INCHES ACROSS VAN BUREN...KALAMAZOO...CALHOUN...AND INGHAM COUNTIES. WE ARE IN THE PROCESS OF SOLICITING REPORTS FROM JACKSON COUNTY. MOST INTENSE SNOWFALL ASSOCIATED WITH A PRONOUNCED FGEN BAND IS EXITING OUR SOUTHEASTERN FORECAST AREA. EXPECT SNOWFALL RATES TO TAPER SIGNIFICANTLY OVER THE NEXT HOUR AS AN UPPER POTENTIAL VORTICITY MAXIMUM SEEN ON WATER VAPOR/IR SATELLITE CHANNELS LIFTS NORTHEAST OUT OF OUR SOUTHEAST FORECAST AREA. LATEST HRRR GUIDANCE INDICATES THE TRAILING EDGE OF PRECIPITATION /CURRENTLY ALONG A MOUNT PLEASANT TO HOLLAND LINE/ WILL EXIT THE FORECAST AREA BY 2 PM. AS SNOW RATES DECREASE WE EXPECT AN UPTICK IN SNOW RATIOS WHICH MAKES BLOWING/DRIFTING SNOW MORE OF A CONCERN AS WINDS INCREASE DURING THE DAY. && .SHORT TERM...(TODAY THROUGH FRIDAY) ISSUED AT 329 AM EDT WED MAR 12 2014 THE MAIN ITEM OF INTEREST IS THE ONGOING SNOW FALLING ACROSS THE SRN PORTION OF THE AREA AND WHAT TO DO WITH THE HEADLINES THIS MORNING. WE WILL HOLD ON TO THE HEADLINES AS THEY ARE FOR NOW AND CONTINUE TO MONITOR THE POSSIBLE NEED TO UPGRADE IN THE NEAR TERM FOR ANY HEAVIER BAND THAT MAY SIT OVER AN AREA FOR A PERIOD. PCPN CHANGED OVER VERY QUICKLY ACROSS THE AREA AROUND 04-06Z THIS MORNING...JUST AS THE MORE WIDESPREAD PCPN BEGAN TO MOVE IN FROM THE SW AND THE COLDER AIR WAS BEING DRAWN DOWN FROM THE NORTH. IT APPEARS THAT WE ARE SEEING THE NRN EXTENT OF THE BETTER PCPN NOW SHAPING UP FROM ROUGHLY GRAND HAVEN TO ALMA. THE SHORT TERM HI-RES MODELS ARE INDICATING THAT THIS EXTENT SHOULD HOLD FOR THE NEXT COUPLE OF HOURS. THIS OCCURS AS WE HAVE THE NRN STREAM AND SRN STREAM THAT WILL BE OFFSETTING EACH OTHERS PUSH. THE NRN STREAM WILL EVENTUALLY DOMINATE AND PUSH THE HEAVIER FGEN SOUTH AND EAST OUT OF THE AREA. THE FAVORED AREA FOR THE HEAVIEST SNOW CONTINUES TO LOOK LIKE IT WILL BE WHERE WE CURRENTLY HAVE THE WARNINGS OUT ACROSS CALHOUN AND JACKSON COUNTIES. THIS IS WHERE THE SNOW WILL BE FALLING THE LONGEST. IT ALSO APPEARS THAT THE HEAVIER BANDS MOVING UP FROM INDIANA WILL ALSO ENHANCE THE SNOW ACROSS THE WARNING AREA. WINDS WILL BE KICKING UP THIS MORNING AS THE STRONGER GRADIENT MOVES OVER THE AREA. THE SNOW WILL INITIALLY BE A LITTLE TOO WET FOR BLOWING AND DRIFTING. AS COLDER AIR CONTINUES TO MOVE IN...THE SNOW WILL BECOME A LITTLE MORE FAVORABLE FOR BLOWING AND DRIFTING. IN THE ADVISORY AREA...WE EXPECT SOME DECENT SNOW RATES TO OCCUR FOR THE NEXT FEW HOURS. WE EXPECT THAT BY 12Z ALREADY THAT THE SNOW WILL BE DIMINISHING IN INTENSITY AND ENDING FROM THE NORTH AND WEST AS THE STRONGEST PHASED MID LEVEL FGEN MIGRATES SE. BLOWING AND DRIFTING SNOW WILL GRADUALLY BECOME MORE LIKELY TOWARD THE END OF THE EVENT IN THIS AREA ALSO. THE THREAT SHOULD DIMINISH ONCE THE SNOW STOPS FALL THIS MORNING. THE WIDESPREAD PCPN IS EXPECTED TO COME TO AN END AT ALL LOCATIONS BY 18Z THIS AFTERNOON. WE HAVE CONTINUED TO LEAVE A SMALL CHC OF SNOW SHOWERS IN THROUGH THE AFTERNOON WITH THE PASSAGE OF THE UPPER TROUGH. STRONG SUBSIDENCE BUILDING IN BEHIND THE TROUGH WILL ALLOW FOR CLEARING TO WORK IN FROM THE NW LATER THIS AFTERNOON. WE CONTINUE TO EXPECT AN ALMOST IDEAL RADIATIONAL COOLING SITUATION FOR TONIGHT. SKIES WILL HAVE CLEARED OUT LATE THIS AFTERNOON...AND THE SFC RIDGE WILL MOVE IN SQUARELY DURING THE OVERNIGHT PERIOD. WITH THE DRY AND COLD ARCTIC AIR MASS EXPECTED TO BE IN PLACE...TEMPS WILL LIKELY FREE FALL TONIGHT AFTER SLOWLY FALLING TEMPS DURING THE DAY TODAY. WE ARE LIKELY LOOKING AT RECORD LOWS FOR 3/13. PLEASE SEE THE CLIMATE SECTION BELOW FOR MORE DETAILS. A FAIRLY QUIET PERIOD CAN THEN BE EXPECTED FOR THE THU THROUGH FRI TIME FRAME WITH MODERATING TEMPS...ESPECIALLY ON FRI. THU CONTINUES TO LOOK LIKE A MUCH BELOW AVERAGE DAY WITH LITTLE TEMP ADVECTION EXPECTED UNTIL LATE IN THE DAY. TEMPS WILL LIKELY RISE THROUGH THU NIGHT AND INTO FRI AS STRONGER WAA TAKES PLACE. IT LOOKS LIKE A BAND OF MID CLOUDS MOVE THROUGH AT THE LEADING EDGE OF THE WARMER AIR ALOFT. A SMALL CHANCE OF PCPN WILL BE POSSIBLE ACROSS THE NRN COUNTIES ON FRI AS LOW PRESSURE MOVES ACROSS LAKE SUPERIOR AND INTO ONTARIO. DEEPER MOISTURE IS SHOWN TO BE PRESENT UP NORTH. .LONG TERM...(FRIDAY NIGHT THROUGH TUESDAY) ISSUED AT 329 AM EDT WED MAR 12 2014 DID NOT MAKE MAJOR CHANGES TO THE GOING LONG TERM FORECAST. GFS AND ECMWF ARE SIMILAR UNTIL EARLY NEXT WEEK. TEMPERATURES THROUGH THE PERIOD WILL GENERALLY BE BELOW NORMAL. AS FOR THE DETAILS...MAINTAINED A CHANCE OF RAIN/SNOW CHANGING TO SNOW FRIDAY NIGHT AS A COLD FRONT DROPS SOUTH INTO THE AREA. 850MB TEMPS COOL TO -5 TO -10 C BY 12Z SATURDAY SO THE CHANGEOVER STILL LOOKS GOOD. THAT SAID...PRECIPITATION DOES NOT LOOK SIGNIFICANT BY ANY MEANS. STILL HAVE 20 PCT POPS FOR SATURDAY AS THERE WILL LIKELY BE SOME SNOW SHOWERS AROUND GIVEN THE NORTHWEST FLOW COLD AIR ADVECTION AND UPPER TROUGHING. AGAIN...LIGHT PRECIPITATION IS EXPECTED. SATURDAY NIGHT THROUGH MONDAY NIGHT MAINTAINED A DRY FORECAST WITH HIGH PRESSURE SHIFTING THROUGH THE GREAT LAKES REGION. MODELS HAVE DIFFERING SOLUTIONS REGARDING THE TUES/WED SYSTEM OF NEXT WEEK. THE GFS IS FARTHER NORTH BRINGING SOUTHERLY FLOW INTO THE AREA...WHILE TH ECMWF IS SOUTH PLACING US NORTH OF A WARM FRONT. HAVE SOME TIME TO GET THIS WORKED OUT...BUT MODELS LEAD TO A LOW CONFIDENCE FORECAST AT THIS POINT FOR MID NEXT WEEK. MIXED PRECIP IN THE FORECAST FOR NOW GIVEN THE UNCERTAINTY. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING) ISSUED AT 747 AM EDT WED MAR 12 2014 LIFR AND IFR CONDITIONS REMAIN IN THE HEAVIER SNOW BANDS EXTENDING FROM THE KAZO AND KBTL AREAS EAST TOWARDS KLAN AND KJXN. THE SNOW WILL QUICKLY LIFT EAST AND DIMINISH THROUGH 16Z THIS MORNING. THIS AFTERNOON...EXPECTING MVFR CEILINGS TO REMAIN WITH VFR VSBY/S IN MANY LOCATIONS. THERE MAY BE SOME BRIEF TIMES WHERE THE STRONG NORTH WINDS OF 15 TO 25 KNOTS CREATE MVFR VSBY/S DUE TO BLOWING SNOW. AT THIS POINT NOT SURE HOW WIDESPREAD THE BLOWING SNOW WILL BE THIS AFTERNOON AS THE SNOW HAS HAD A HIGHER MOISTURE CONTENT. SO...BOTTOM LINE TODAY...IFR/LIFR SNOW THIS MORNING LIFTING OUT TOWARDS MIDDAY DAY. STRONG NORTH WINDS THIS AFTERNOON. VFR CONDITIONS ARE EXPECTED FROM LATE THIS AFTERNOON...AFTER 22Z...THROUGH TONIGHT. SKIES SHOULD ACTUALLY BECOME MOSTLY CLEAR TONIGHT. && .HYDROLOGY... ISSUED AT 302 PM EDT TUE MAR 11 2014 RISES UNDERWAY AND TODAYS WARMER THAN EXPECTED TEMPERATURES ARE ALLOWING FOR SOME ENHANCED RUNOFF. STILL WE ARE NOT EXPECTING ANY HIGHER IMPACTS FROM THIS INITIAL SURGE OF RUNOFF. WITH ICE IN THE RIVERS...WE STILL NEED TO MONITOR FORECAST POINTS CLOSELY. TEMPERATURES WILL FALL WELL BELOW FREEZING ON WEDNESDAY AND THAT SHOULD LOCK UP THE RUNOFF FOR A FEW DAYS. && .CLIMATE... ISSUED AT 329 AM EDT WED MAR 12 2014 THE COLD AIR MASS COMING IN...COMBINED WITH DIMINISHING WINDS AND CLEARING SKIES TONIGHT WILL ALLOW TEMPERATURES TO APPROACH OR EXCEED RECORDS FOR MARCH 13TH. THERE IS EVEN A SLIGHT CHANCE TEMPERATURES COULD FALL QUICK ENOUGH BEFORE THE END OF THE CLIMATE DAY FOR TODAY THAT RECORDS COULD BE APPROACHED FOR THE 12TH. HERE ARE THE RECORDS: 3/12 3/13 GRAND RAPIDS 2 DEGREES - 1993...1948 5 DEGREES - 1926 MUSKEGON 2 DEGREES - 1979 2 DEGREES - 1912 LANSING -3 DEGREES - 1877 -3 DEGREES - 1960 && .GRR WATCHES/WARNINGS/ADVISORIES... MI...WINTER WEATHER ADVISORY UNTIL 3 PM EDT THIS AFTERNOON FOR MIZ057>059-064>067-071-072. WINTER STORM WARNING UNTIL 3 PM EDT THIS AFTERNOON FOR MIZ073- 074. LM...NONE. && $$ UPDATE...WDM SYNOPSIS...NJJ SHORT TERM...NJJ LONG TERM...DUKE AVIATION...DUKE HYDROLOGY...MJS CLIMATE...NJJ
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
942 AM EDT WED MAR 12 2014 LATEST UPDATE... UPDATE .SYNOPSIS... ISSUED AT 329 AM EDT WED MAR 12 2014 SNOW FALLING ACROSS THE SOUTHERN TWO THIRDS OF THE AREA THIS MORNING WILL GRADUALLY END THIS MORNING AND INTO EARLY THIS AFTERNOON FROM NW TO SE. HIGHEST SNOW ACCUMULATIONS WILL BE FOUND SOUTH OF I-69. SOME BLOWING AND DRIFTING SNOW WILL BE POSSIBLE AS WIND INCREASE THIS MORNING. SNOW AND CLOUDS WILL CLEAR OUT BY TONIGHT...ALLOWING FOR A RECORD COLD NIGHT FOR THE AREA. AFTER ANOTHER COLD DAY ON THURSDAY...TEMPERATURES WILL WARM BACK UP FOR FRIDAY WITH A SMALL CHANCE OF RAIN UP NORTH IN THE AFTERNOON. COLDER AIR AND A CHANCE FOR SNOW SHOWERS WILL MOVE BACK IN FOR SATURDAY. && .UPDATE... ISSUED AT 942 AM EDT WED MAR 12 2014 GREATEST SNOWFALL REPORTS SO FAR HAVE RANGED FROM 6 TO 7.5 INCHES ACROSS VAN BUREN...KALAMAZOO...CALHOUN...AND INGHAM COUNTIES. WE ARE IN THE PROCESS OF SOLICITING REPORTS FROM JACKSON COUNTY. MOST INTENSE SNOWFALL ASSOCIATED WITH A PRONOUNCED FGEN BAND IS EXITING OUR SOUTHEASTERN FORECAST AREA. EXPECT SNOWFALL RATES TO TAPER SIGNIFICANTLY OVER THE NEXT HOUR AS AN UPPER POTENTIAL VORTICITY MAXIMUM SEEN ON WATER VAPOR/IR SATELLITE CHANNELS LIFTS NORTHEAST OUT OF OUR SOUTHEAST FORECAST AREA. LATEST HRRR GUIDANCE INDICATES THE TRAILING EDGE OF PRECIPITATION /CURRENTLY ALONG A MOUNT PLEASANT TO HOLLAND LINE/ WILL EXIT THE FORECAST AREA BY 2 PM. AS SNOW RATES DECREASE WE EXPECT AN UPTICK IN SNOW RATIOS WHICH MAKES BLOWING/DRIFTING SNOW MORE OF A CONCERN AS WINDS INCREASE DURING THE DAY. && .SHORT TERM...(TODAY THROUGH FRIDAY) ISSUED AT 329 AM EDT WED MAR 12 2014 THE MAIN ITEM OF INTEREST IS THE ONGOING SNOW FALLING ACROSS THE SRN PORTION OF THE AREA AND WHAT TO DO WITH THE HEADLINES THIS MORNING. WE WILL HOLD ON TO THE HEADLINES AS THEY ARE FOR NOW AND CONTINUE TO MONITOR THE POSSIBLE NEED TO UPGRADE IN THE NEAR TERM FOR ANY HEAVIER BAND THAT MAY SIT OVER AN AREA FOR A PERIOD. PCPN CHANGED OVER VERY QUICKLY ACROSS THE AREA AROUND 04-06Z THIS MORNING...JUST AS THE MORE WIDESPREAD PCPN BEGAN TO MOVE IN FROM THE SW AND THE COLDER AIR WAS BEING DRAWN DOWN FROM THE NORTH. IT APPEARS THAT WE ARE SEEING THE NRN EXTENT OF THE BETTER PCPN NOW SHAPING UP FROM ROUGHLY GRAND HAVEN TO ALMA. THE SHORT TERM HI-RES MODELS ARE INDICATING THAT THIS EXTENT SHOULD HOLD FOR THE NEXT COUPLE OF HOURS. THIS OCCURS AS WE HAVE THE NRN STREAM AND SRN STREAM THAT WILL BE OFFSETTING EACH OTHERS PUSH. THE NRN STREAM WILL EVENTUALLY DOMINATE AND PUSH THE HEAVIER FGEN SOUTH AND EAST OUT OF THE AREA. THE FAVORED AREA FOR THE HEAVIEST SNOW CONTINUES TO LOOK LIKE IT WILL BE WHERE WE CURRENTLY HAVE THE WARNINGS OUT ACROSS CALHOUN AND JACKSON COUNTIES. THIS IS WHERE THE SNOW WILL BE FALLING THE LONGEST. IT ALSO APPEARS THAT THE HEAVIER BANDS MOVING UP FROM INDIANA WILL ALSO ENHANCE THE SNOW ACROSS THE WARNING AREA. WINDS WILL BE KICKING UP THIS MORNING AS THE STRONGER GRADIENT MOVES OVER THE AREA. THE SNOW WILL INITIALLY BE A LITTLE TOO WET FOR BLOWING AND DRIFTING. AS COLDER AIR CONTINUES TO MOVE IN...THE SNOW WILL BECOME A LITTLE MORE FAVORABLE FOR BLOWING AND DRIFTING. IN THE ADVISORY AREA...WE EXPECT SOME DECENT SNOW RATES TO OCCUR FOR THE NEXT FEW HOURS. WE EXPECT THAT BY 12Z ALREADY THAT THE SNOW WILL BE DIMINISHING IN INTENSITY AND ENDING FROM THE NORTH AND WEST AS THE STRONGEST PHASED MID LEVEL FGEN MIGRATES SE. BLOWING AND DRIFTING SNOW WILL GRADUALLY BECOME MORE LIKELY TOWARD THE END OF THE EVENT IN THIS AREA ALSO. THE THREAT SHOULD DIMINISH ONCE THE SNOW STOPS FALL THIS MORNING. THE WIDESPREAD PCPN IS EXPECTED TO COME TO AN END AT ALL LOCATIONS BY 18Z THIS AFTERNOON. WE HAVE CONTINUED TO LEAVE A SMALL CHC OF SNOW SHOWERS IN THROUGH THE AFTERNOON WITH THE PASSAGE OF THE UPPER TROUGH. STRONG SUBSIDENCE BUILDING IN BEHIND THE TROUGH WILL ALLOW FOR CLEARING TO WORK IN FROM THE NW LATER THIS AFTERNOON. WE CONTINUE TO EXPECT AN ALMOST IDEAL RADIATIONAL COOLING SITUATION FOR TONIGHT. SKIES WILL HAVE CLEARED OUT LATE THIS AFTERNOON...AND THE SFC RIDGE WILL MOVE IN SQUARELY DURING THE OVERNIGHT PERIOD. WITH THE DRY AND COLD ARCTIC AIR MASS EXPECTED TO BE IN PLACE...TEMPS WILL LIKELY FREE FALL TONIGHT AFTER SLOWLY FALLING TEMPS DURING THE DAY TODAY. WE ARE LIKELY LOOKING AT RECORD LOWS FOR 3/13. PLEASE SEE THE CLIMATE SECTION BELOW FOR MORE DETAILS. A FAIRLY QUIET PERIOD CAN THEN BE EXPECTED FOR THE THU THROUGH FRI TIME FRAME WITH MODERATING TEMPS...ESPECIALLY ON FRI. THU CONTINUES TO LOOK LIKE A MUCH BELOW AVERAGE DAY WITH LITTLE TEMP ADVECTION EXPECTED UNTIL LATE IN THE DAY. TEMPS WILL LIKELY RISE THROUGH THU NIGHT AND INTO FRI AS STRONGER WAA TAKES PLACE. IT LOOKS LIKE A BAND OF MID CLOUDS MOVE THROUGH AT THE LEADING EDGE OF THE WARMER AIR ALOFT. A SMALL CHANCE OF PCPN WILL BE POSSIBLE ACROSS THE NRN COUNTIES ON FRI AS LOW PRESSURE MOVES ACROSS LAKE SUPERIOR AND INTO ONTARIO. DEEPER MOISTURE IS SHOWN TO BE PRESENT UP NORTH. .LONG TERM...(FRIDAY NIGHT THROUGH TUESDAY) ISSUED AT 329 AM EDT WED MAR 12 2014 DID NOT MAKE MAJOR CHANGES TO THE GOING LONG TERM FORECAST. GFS AND ECMWF ARE SIMILAR UNTIL EARLY NEXT WEEK. TEMPERATURES THROUGH THE PERIOD WILL GENERALLY BE BELOW NORMAL. AS FOR THE DETAILS...MAINTAINED A CHANCE OF RAIN/SNOW CHANGING TO SNOW FRIDAY NIGHT AS A COLD FRONT DROPS SOUTH INTO THE AREA. 850MB TEMPS COOL TO -5 TO -10 C BY 12Z SATURDAY SO THE CHANGEOVER STILL LOOKS GOOD. THAT SAID...PRECIPITATION DOES NOT LOOK SIGNIFICANT BY ANY MEANS. STILL HAVE 20 PCT POPS FOR SATURDAY AS THERE WILL LIKELY BE SOME SNOW SHOWERS AROUND GIVEN THE NORTHWEST FLOW COLD AIR ADVECTION AND UPPER TROUGHING. AGAIN...LIGHT PRECIPITATION IS EXPECTED. SATURDAY NIGHT THROUGH MONDAY NIGHT MAINTAINED A DRY FORECAST WITH HIGH PRESSURE SHIFTING THROUGH THE GREAT LAKES REGION. MODELS HAVE DIFFERING SOLUTIONS REGARDING THE TUES/WED SYSTEM OF NEXT WEEK. THE GFS IS FARTHER NORTH BRINGING SOUTHERLY FLOW INTO THE AREA...WHILE TH ECMWF IS SOUTH PLACING US NORTH OF A WARM FRONT. HAVE SOME TIME TO GET THIS WORKED OUT...BUT MODELS LEAD TO A LOW CONFIDENCE FORECAST AT THIS POINT FOR MID NEXT WEEK. MIXED PRECIP IN THE FORECAST FOR NOW GIVEN THE UNCERTAINTY. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING) ISSUED AT 747 AM EDT WED MAR 12 2014 LIFR AND IFR CONDITIONS REMAIN IN THE HEAVIER SNOW BANDS EXTENDING FROM THE KAZO AND KBTL AREAS EAST TOWARDS KLAN AND KJXN. THE SNOW WILL QUICKLY LIFT EAST AND DIMINISH THROUGH 16Z THIS MORNING. THIS AFTERNOON...EXPECTING MVFR CEILINGS TO REMAIN WITH VFR VSBY/S IN MANY LOCATIONS. THERE MAY BE SOME BRIEF TIMES WHERE THE STRONG NORTH WINDS OF 15 TO 25 KNOTS CREATE MVFR VSBY/S DUE TO BLOWING SNOW. AT THIS POINT NOT SURE HOW WIDESPREAD THE BLOWING SNOW WILL BE THIS AFTERNOON AS THE SNOW HAS HAD A HIGHER MOISTURE CONTENT. SO...BOTTOM LINE TODAY...IFR/LIFR SNOW THIS MORNING LIFTING OUT TOWARDS MIDDAY DAY. STRONG NORTH WINDS THIS AFTERNOON. VFR CONDITIONS ARE EXPECTED FROM LATE THIS AFTERNOON...AFTER 22Z...THROUGH TONIGHT. SKIES SHOULD ACTUALLY BECOME MOSTLY CLEAR TONIGHT. && .HYDROLOGY... ISSUED AT 302 PM EDT TUE MAR 11 2014 RISES UNDERWAY AND TODAYS WARMER THAN EXPECTED TEMPERATURES ARE ALLOWING FOR SOME ENHANCED RUNOFF. STILL WE ARE NOT EXPECTING ANY HIGHER IMPACTS FROM THIS INITIAL SURGE OF RUNOFF. WITH ICE IN THE RIVERS...WE STILL NEED TO MONITOR FORECAST POINTS CLOSELY. TEMPERATURES WILL FALL WELL BELOW FREEZING ON WEDNESDAY AND THAT SHOULD LOCK UP THE RUNOFF FOR A FEW DAYS. && .CLIMATE... ISSUED AT 329 AM EDT WED MAR 12 2014 THE COLD AIR MASS COMING IN...COMBINED WITH DIMINISHING WINDS AND CLEARING SKIES TONIGHT WILL ALLOW TEMPERATURES TO APPROACH OR EXCEED RECORDS FOR MARCH 13TH. THERE IS EVEN A SLIGHT CHANCE TEMPERATURES COULD FALL QUICK ENOUGH BEFORE THE END OF THE CLIMATE DAY FOR TODAY THAT RECORDS COULD BE APPROACHED FOR THE 12TH. HERE ARE THE RECORDS: 3/12 3/13 GRAND RAPIDS 2 DEGREES - 1993...1948 5 DEGREES - 1926 MUSKEGON 2 DEGREES - 1979 2 DEGREES - 1912 LANSING -3 DEGREES - 1877 -3 DEGREES - 1960 && .GRR WATCHES/WARNINGS/ADVISORIES... MI...WINTER WEATHER ADVISORY UNTIL 3 PM EDT THIS AFTERNOON FOR MIZ057>059-064>067-071-072. WINTER STORM WARNING UNTIL 3 PM EDT THIS AFTERNOON FOR MIZ073- 074. LM...NONE. && $$ UPDATE...TJT SYNOPSIS...NJJ SHORT TERM...NJJ LONG TERM...DUKE AVIATION...DUKE HYDROLOGY...MJS CLIMATE...NJJ
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
743 AM EDT WED MAR 12 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 403 AM EDT WED MAR 12 2014 THE COLD FRONT THAT SHIFTED SOUTH ACROSS UPPER MICHIGAN LATE YESTERDAY AFTERNOON AND EVENING PRODUCED SNOW SHOWERS OVER MUCH OF WESTERN AND CENTRAL UPPER MICHIGAN...WITH THE STRONGEST SHOWERS SEEN OVER NORTH CENTRAL UPPER MICHIGAN. THIS WAS DUE TO THE NORTH TO NORTHEAST WINDS PROVIDING TERRAIN ENHANCEMENT TO THE LIGHTER SNOW SHOWERS AND ENDED UP PRODUCING ABOUT AN INCH OF SNOW AT OUR OFFICE THROUGH 2AM. THE INTENSITY HAS REALLY DIMINISHED OVER THE LAST HOUR OR TWO DUE TO THE DRY AIR (ASSOCIATED WITH THE HIGH OVER NORTHWEST ONTARIO) THAT HAS BEEN SURGING SOUTH ACROSS LAKE SUPERIOR ON IR SATELLITE. WITH LIMITED BREAKS IN THE ICE...THE COLD AIR (RAP ANALYZED 900MB TEMPERATURES OF -17C) HAS ONLY BEEN ABLE TO PRODUCE A COUPLE LAKE EFFECT CLOUD STREAMERS OFF THE OPEN AREA NEAR ISLE ROYALE AND THAT IS STRETCHING TOWARDS AREAS SOUTHWEST OF THE PORCUPINE MOUNTAINS. THIS DRYING ABOVE 900MB HAS LED TO SIGNIFICANT ADJUSTMENTS TO THE GOING FORECAST. SINCE THE HIGH WILL CONTINUE TO SLIDE SOUTHEAST OVER THE AREA THROUGH THE DAY TODAY...HAVE TRENDED THE FORECAST TOWARDS A FASTER END TO THE SNOW. WOULD EXPECT THE CLOUDS AND LIGHT SNOW SHOWERS OR FLURRIES TO REMAIN THE LONGEST OVER THE NORTH CENTRAL U.P. WHERE THE NORTHEAST WINDS WILL REMAIN MOST FAVORABLE. LOOKING AT 00Z NAM/GFS SOUNDINGS THEY DO HOLD ONTO MOISTURE RIGHT BELOW THAT INVERSION INTO THE AFTERNOON FOR KSAW...BUT THE LAST SEVERAL RAP RUNS REALLY SCOUR THAT MOISTURE OUT. THUS...WILL KEEP THE TREND TOWARDS PARTLY CLOUDY SKIES BY AFTERNOON OVER THE NORTH CENTRAL AND PARTLY CLOUDY TO MOSTLY SUNNY ELSEWHERE AWAY FROM THE UPSLOPE FLOW. AS FOR THE SNOW SHOWERS...HAVE CUT THAT BACK SIGNIFICANTLY...WITH THEM MAINLY BEING CONFINED TO THE NORTH CENTRAL FOR THE NEXT FEW HOURS AND THEN QUICKLY DIMINISHING DURING THE MORNING WITH THE WINDS STARTING TO BACK MORE TO THE NORTH-NORTHWEST. WILL MONITOR CLOUD/SNOW TRENDS THROUGH DAY BREAK AND MAY NEED TO DIMINISH THEM EVEN EARLIER THAN THE GOING FORECAST. WITH THE COLD AIR ALOFT THAT IS MOVING OVER THE AREA...EXPECT THE EARLY MORNING TEMPERATURES TO CONTINUE TO SLOWLY FALL. THE 3AM OBS (RANGING FROM 9 DEGREES IN COPPER HARBOR AND 27 IN MENOMINEE) WILL LIKELY BE THE WARMEST VALUES FOR THE RESPECTIVE LOCATIONS AND ONLY HAVE HIGHS IN THE UPPER SINGLE DIGITS TO THE NORTH AND THE MID TEENS TO THE SOUTH. AM A LITTLE CONCERNED THE WARM MARCH SUN THIS AFTERNOON COULD PRODUCE HIGHS A LITTLE WARMER THAN EXPECTED AND DID ADJUST INLAND WEST AREAS UP A COUPLE DEGREES TO ACCOUNT FOR THIS. FOR SEVERAL COOP SITES OVER THE WEST THAT REPORT ON A 7AM-7AM CYCLE...DAYTIME HIGHS TODAY COULD BE NEAR OR BREAK RECORD LOW HIGHS FOR THE OBS THAT WILL BE REPORTED ON MARCH 13TH. WITH THE HIGH BEING OVER DIRECTLY OVER THE U.P. THIS EVENING AND CLEAR SKIES...EXPECT TEMPERATURES TO QUICKLY DROP OVER THE WEST AND CENTRAL INITIALLY WITH THE LIGHT WINDS. THOSE AREAS SHOULD SEE THEIR LOWS EARLIER THAN THE EAST DUE TO THE HIGH SHIFTING SOUTHEAST OF THE AREA LATE TONIGHT AND ALLOWING SOUTHERLY FLOW TO DEVELOP. IN ADDITION...MID CLOUDS WILL BE ARRIVING OVER THE WEST LATE IN RESPONSE TO INCREASING WARM AIR ADVECTION ALOFT AND COULD EVEN LEAD TO SOME LIGHT SNOW SHOWERS OVER THE WESTERN QUARTER OF LAKE SUPERIOR BEFORE 12Z. OVER THE EAST...THE LATER WEAKENING OF THE WINDS SHOULDN/T HAVE MUCH AFFECT ON THE LOWS AND EXPECT THE LONGER RADIATIONAL COOLING TIME TO ALLOW LOWS TO EASILY FALL INTO THE TEENS BELOW ZERO. WILL CONTINUE TO FOLLOW THE NH/REGIONAL CANADIAN MODEL FOR TEMPERATURES OVER THE EAST...DUE TO IT/S GREAT PERFORMANCE THIS WINTER ON THESE TYPES OF NIGHTS. DID TREND LOWS DOWN A LITTLE FOR SOME OF THE TRADITIONAL COLD SPOTS (RAWS SITES LIKE DOE LAKE AND SPINCICH LAKE)...WHICH WILL LIKELY SEE VALUES FALLING INTO THE LOWER -20S. CURRENT FORECAST HAS LOWS NEARING/BREAKING RECORDS FOR MANISTIQUE (-7 IN 1948) AND MUNISING (-10 IN 1926). .LONG TERM...(THURSDAY THROUGH TUESDAY) ISSUED AT 513 AM EDT WED MAR 12 2014 THE OVERALL PATTERN WILL CONTINUE TO BE INFLUENCED BY RIDGING OVER WRN NOAM AND THE RESULTING DOWNSTREAM TROUGH INTO THE GREAT LAKES AND NERN CONUS...KEEPING TEMPS MAINLY BELOW NORMAL. A CLIPPER SHORTWAVE AND LOW MOVING THROUGH THE REGION WILL BRING A WARMUP FRIDAY WITH A CHANCE OF SOME LIGHT PCPN BUT WILL DRAG MUCH COLDER AIR INTO THE REGION IN ITS WAKE FOR THE WEEKEND. THU...AS ARCTIC HIGH PRES SHIFTS TO THE EAST AND MID LEVEL RIDGING BUILDS TOWARD THE UPPER MS VALLEY...WAA WILL SPREAD CLOUDS THROUGH UPPER MICHIGAN. ONLY SLIGHT CHANCE POPS FOR LIGHT SNOW WERE INCLUDED GIVEN ONLY LIMITED MOISTURE AVAILABILITY AND RELATIVELY SMALL NET ISENTROPIC LIFT AS THE 850-700 MB LAYER WARMS. A LARGE SPREAD OF HIGH TEMPS IS EXPECTED WITH READINGS RANGING FROM AROUND 20 NEAR ERY TO 40 AT IWD. THU NIGHT INTO FRI...THE GEM AND ECMWF HAVE REMAINED FARTHER SOUTH WITH THE TRACK OF THE CLIPPER SHRTWV COMPARED TO THE NAM AND GFS. EVEN THOUGH THERE IS LINGERING MODEL UNCERTAINTY...THERE SHOULD BE ENOUGH 700-300 MB QVECTOR CONV WITH THIS FEATURE TO SUPPORT AT LEAST LOW END PCPN CHANCES OVER MOST OF THE CWA FRI...ESPECIALLY OVER THE NORTH HALF. ALTHOUGH THERE MAY BE ENOUGH WARM AIR IN THE WARM SECTOR TO SUPPORT SOME LIGHT RAIN...WET-BULB ZERO HEIGHTS FAVOR MAINLY SNOW. HIGHS SHOULD STILL CLIMB ABOVE NORMAL INTO THE MID AND UPPER 30S. FRI NIGHT AND SAT...THE LOW PRESSURE SYSTEM WILL DRAG A COLD FRONT THROUGH UPPER MI WITH 850 MB TEMPS FALLING TO NEAR -14C BY 12Z/SAT AND -20C BY 00Z/SUN. THE MOST FAVORABLE PERIOD FOR SNOW SHOWERS... AIDED BY HEAT/MOISTURE FLUX ACROSS SOME GAPS IN THE ICE COVER AND UPSLOPE FLOW INTO THE HIGHER TERRAIN...WILL BE BETWEEN 06Z-18Z WHEN THE GREATER 850-700 MB MOISTURE AND IS PRESENT. ANY SNOW SHOWERS STILL BE LIGHT...GENERALLY ONLY AN INCH OR TWO AT MOST. TEMPS WILL STRUGGLE TO AROUND 20 NORTH BUT MAY CLIMB TO THE UPPER 20S SOUTH. SUN-TUE...AS THE ARCTIC HIGH SETTLES INTO THE REGION SUN...HIGHS WILL REMAIN IN THE TEENS UNDER MOSTLY SUNNY SKIES AFTER MORNING LOWS AT OR JUST BELOW ZERO. MODEL DIFFERENCES ARE MUCH GREATER BY MON-TUE AS THE ECMWF KEEPS MORE TROUGHING AND COLD AIR OVER THE GREAT LAKES COMPARED TO THE GFS/GEM WHICH KEEPS MOST OF THE PCPN WITH A SHRTWV AND LOW TO THE SOUTH AND WEST OF UPPER MICHIGAN. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING) ISSUED AT 743 AM EDT WED MAR 12 2014 DRY AIR ASSOCIATED WITH AN AREA OF HIGH PRESSURE JUST TO THE NORTHWEST OF LAKE SUPERIOR CONTINUES TO DIMINISH CLOUDS ACROSS LAKE SUPERIOR...ALTHOUGH THERE AREA A COUPLE LAKE EFFECT BANDS OVER THE WESTERN HALF OF THE LAKE FROM OPEN WATER NEAR ISLE ROYALE. WITH THE HIGH MOVING OVER THE U.P. THIS AFTERNOON...EXPECT VFR CONDITIONS TO REMAIN AT KIWD/KCMX THROUGH THE PERIOD. AT KSAW...UPSLOPE NORTHEAST WINDS ARE CAUSING MVFR CLOUDS (AND ISOLATED SNOW SHOWERS) TO LINGER...BUT WOULD EXPECT THOSE TO SCATTER OUT AROUND MID DAY. ONCE THOSE SCATTER OUT VFR CONDITIONS WILL PREVAIL. AN APPROACHING CLIPPER SYSTEM FOR THURSDAY NIGHT WILL BRING INCREASING CLOUDS LATE TONIGHT AND MAYBE A FEW SNOW SHOWERS AT KIWD/KCMX JUST AFTER THE END OF THE TAF PERIOD. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 403 AM EDT WED MAR 12 2014 COLD AIR SURGING SOUTH ACROSS LAKE SUPERIOR THIS PAST EVENING LED TO A PERIOD OF NORTHERLY GUSTS TO 25-30KTS OVER MUCH OF THE LAKE. THESE WINDS ARE EXPECTED TO QUICKLY DIMINISH TODAY AS AN AREA OF HIGH PRESSURE IN NORTHWEST ONTARIO QUICKLY SHIFTS SOUTHEAST OVER THE UPPER GREAT LAKES REGION. THIS HIGH WILL EXIT THE AREA LATE TONIGHT AND THURSDAY MORNING ALLOWING SOUTHWESTERLY WINDS TO START TO INCREASE AHEAD OF THE NEXT CLIPPER SYSTEM THAT WILL MOVE ACROSS LAKE SUPERIOR THURSDAY NIGHT AND FRIDAY MORNING. SOUTHWEST WINDS MAY INCREASE TO 15-25KTS AHEAD OF THIS LOW...THEN SHIFT TO THE NORTHWEST AT SIMILAR VALUES ON THE BACK SIDE OF THE LOW. HIGH PRESSURE WILL THEN BUILD SOUTH FROM CANADA SATURDAY AFTERNOON INTO SUNDAY AND PRODUCE WEAKENING WINDS. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...SRF LONG TERM...JLB AVIATION...SRF MARINE...SRF
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
727 AM EDT WED MAR 12 2014 .AVIATION... //DISCUSSION... VLIFR/LIFR RESTRICTION IN MODERATE TO HEAVY SNOW WILL PERSIST FOR THE BULK OF THE MORNING FROM FNT SOUTHWARD THROUGH THE DTW CORRIDOR. ADD TO THAT A NORTH WIND GUSTING UP AROUND 30 KNOTS TO COMPLICATE CONDITIONS FOR AVIATION OPERATIONS BOTH ON THE GROUND AND IN THE AIR. MBS WILL WAVER BETWEEN IFR AND MVFR AND THESE CONDITIONS WILL SPREAD SOUTHWARD OVER THE REST OF THE SITES AS AN IMPROVEMENT DURING LATE MORNING AND EARLY AFTERNOON AS THE STRONG WINTER STORM SYSTEM EXITS THE AREA. A NEW SURGE OF ARCTIC AIR WILL FOSTER A CLEARING TREND DURING THE EVENING WITH CLEAR AND COLD CONDITIONS IN PLACE AFTER MIDNIGHT THROUGH SUNRISE THURSDAY. FOR DTW... NEAR ZERO VISIBILITY AND SNOWFALL RATES OF 1-2 INCHES PER HOUR WILL PERSIST THROUGH MID MORNING RESULTING IN TOTAL ACCUMULATION CLOSER TO THE 9 INCH END OF THE 6-9 INCH RANGE OF THE FORECAST. IMPROVEMENT WILL THEN BE GRADUAL THROUGH IFR TO MVFR IN BLOWING SNOW BY EARLY AFTERNOON. THIS WILL BE DUE TO NORTH WIND GUSTING NEAR 35 KNOTS AT TIMES UNTIL CLOSE TO SUNSET. //DTW THRESHOLD THREATS... * MODERATE CONFIDENCE IN 1/4SM VISIBILITY AND 200FT CEILING. * HIGH CONFIDENCE ON CEILING BELOW 5000 FEET TODAY. * HIGH CONFIDENCE IN SNOW AS PRECIPITATION TYPE. && .PREV DISCUSSION...ISSUED 353 AM EDT WED MAR 12 2014 SHORT TERM... TODAY AND TONIGHT A HIGH IMPACT WINTER STORM SYSTEM REMAINS ON TRACK FOR THE SOUTH HALF OF SE MICHIGAN WITH THE PEAK OF THE EVENT DURING THE MORNING COMMUTE ALONG AND SOUTH OF THE I-69 CORRIDOR. THE SYSTEM WILL BRING HEAVY SNOW AND STRONG WIND OVER THE REGION DURING THE MORNING BEFORE DIMINISHING DURING EARLY AFTERNOON. HEADLINE ADJUSTMENTS CONSIST OF A WARNING UPGRADE TO LIVINGSTON, SHIAWASSEE, GENESEE, AND LAPEER. THE CHARACTER OF THIS EVENT CONTINUES TO EXHIBIT A SHARP SNOWFALL GRADIENT ON THE NORTH FLANK TO THE DEGREE THAT THE NORTHERN REACHES OF MIDLAND AND BAY COUNTIES WILL SEE JUST A DUSTING OF ACCUMULATION WHILE LOCATIONS ALONG THE I-69 CORRIDOR COULD SEE 6 INCHES IN 9 HOURS, AND LOCATIONS CLOSE TO THE OHIO BORDER COULD APPROACH 10 INCHES IF MESOSCALE ELEMENTS LINE UP JUST RIGHT. IN ADDITION, STRONG NORTHERLY WIND GUSTS COULD PRODUCE NEAR BLIZZARD CONDITIONS AT TIMES. AIDING IN THE DETERMINATION OF HEADLINE ADJUSTMENTS IS THE 00Z MODEL SUITE COMING IN WITH SOLID AGREEMENT ON THE TRACK OF THE SURFACE LOW DIRECTLY ALONG THE OHIO RIVER TO THE SOUTHWEST PENNSYLVANIA/WEST VIRGINIA BORDER BY NOON. THAT HELPS ADD CONFIDENCE TO THE LOCATION, INTENSITY, AND DURATION OF MESOSCALE FORCING FEATURES TARGETED FOR THE SLIGHT NORTHWARD EXPANSION OF THE WARNING AREA. IT ALSO REINFORCES THE IDEA OF HIGHLIGHTING THE WIND FOR HURON AND SANILAC COUNTIES GIVEN THE SHARP GRADIENT OF MEANINGFUL SNOW ACCUMULATION THERE. SURFACE OBSERVATIONS AND RADAR DEPICTION AROUND THE MIDNIGHT HOUR REVEALED THE TENDENCY FOR A RAPID CHANGE TO ALL SNOW IN REGIONS OF HIGHER PRECIPITATION RATE WITHIN THE LEADING ARM OF MID LEVEL FRONTAL FORCING. AFTER A BRIEF LULL, AND WITH ADDITIONAL LOW LEVEL COLD ADVECTION, IT IS NO SURPRISE THAT THIS REGION OF THE SYSTEM HAS LIT UP AGAIN WITH ALL SNOW AS THE PRIMARY MOISTURE SURGE ARRIVES. A CLOSED CIRCULATION AND TRUE TROWAL STRUCTURE WILL BE ABSENT FROM THE SYSTEM BUT A DEEP AND DYNAMIC DEFORMATION ZONE ON THE NW FLANK OF THE LOW WILL ENSURE A STRONG MESOSCALE RESPONSE TO FORCING AS THE SYSTEM MOVES THROUGH SE MICHIGAN. THE FIRST SIGNS OF THIS PROCESS IS THE RAPID CLOUD TOP COOLING IN IR SATELLITE IMAGERY BETWEEN MIDNIGHT AND 3 AM WITH RADAR COMPOSITE INDICATING A WIDE BAND OF HEAVY PRECIPITATION FROM NORTHERN MISSOURI INTO OUR AREA ALONG THE I-69 CORRIDOR. CONVECTIVE ELEMENTS TO THE SOUTH ARE MORE INDICATIVE OF CONVECTIVE INSTABILITY IN THE FRONTAL ZONE BELOW 850 MB, AND THIS IS WHERE LIGHTNING STRIKES SHOULD REMAIN, BUT SOME THUNDER SNOW WITHIN THE DEFORMATION AXIS IS NOT OUT OF THE QUESTION AS FAR NORTH AS METRO DETROIT. MODEL CROSS SECTIONS INDICATE IMPRESSIVE CONVECTIVE INSTABILITY IN THE 700-500 MB LAYER MATCHING UP WELL WITH THE OBSERVED BAND FILLING IN OVER THE SOUTH HALF OF SE MICHIGAN. THIS, ALONG WITH SPECIFIC HUMIDITY OF 3-4 G/KG WILL MAKE MAXIMUM USE OF A DEEP WEDGE OF FRONTOGENESIS EXCEEDING 100 UNITS. SIMILAR DEPICTION IN THE LATEST RAP OUTPUT INDICATES THE BURST OF HEAVY SNOWFALL RATES FROM HIGHER ALTITUDE AND WITH HIGHER SNOW RATIO PERSISTING THROUGH CENTRAL SECTIONS OF THE REGION WITH A PIVOT OCCURRING IN THE 12-15Z TIME PERIOD BEFORE MIGRATING SOUTHWARD AND EASTWARD DURING THE LATE MORNING. THIS IS THE SUSPECTED SOURCE OF OVERACHIEVEMENT IN SNOWFALL TOTALS ON THE NORTHERN FRINGES OF THE WARNING AREA. FARTHER SOUTH, THE GOING 6 TO 9 INCH FORECAST LOOKS SOLID AS THE MID LEVEL FRONTAL ZONE AND DEFORMATION ZONE FILL IN TO FORM ONE SOLID NW FLANK OF THE SYSTEM WITH 1-2 INCH PER HOUR PEAK RATES FOR LONGER DURATION THAN POINTS NORTH. THE SYSTEM WILL EXIT THE AREA BY MID AFTERNOON WITH TRAILING NORTHERLY FLOW CARRYING IN ANOTHER ROUND OF ARCTIC AIR. DEPENDING ON THE CLEARING TREND, BELOW ZERO MIN TEMPS ARE ON TARGET WITH FRESH SNOW COVER BY SUNRISE THURSDAY. LONG TERM...THURSDAY THROUGH TUESDAY A QUICK LOOK AT THE LONGWAVE PATTERN THROUGH THE NEXT WEEK SHOW SPLIT FLOW OVER THE WEST COAST WITH THE TROUGH STILL HOLDING ON OVER THE EASTERN CONUS. THE JET STREAM IS VERY ACTIVE/ENERGETIC...BOTH NORTHERN AND SOUTHERN STREAMS...BUT AT THIS POINT IT LOOKS LIKE THE MAJORITY OF THE PRECIP WILL TRY TO STEER CLEAR OF SOUTHERN MI. THE GOOD NEWS IS THAT WE ARE STILL GETTING SURGES OF SOUTHERLY FLOW EVERY THIRD DAY OR SO...BUT THE BAD NEWS IS THAT THESE WARM UPS INTO THE LOW 40S ARE STRUGGLING TO REACH MID MARCH AVERAGE HIGH TEMPS WHICH ARE IN THE MID 40S. TO SUM IT UP...THE MARCH ROLLER COASTER/WAVE TRAIN WILL CONTINUE FOR THE FORESEEABLE FUTURE. WILL NOW HIT ON A FEW FEATURES OF NOTE IN THE EXTENDED PERIOD. THURSDAY WILL BE A COLD DAY AS THE MID/UPPER LEVEL ARCTIC TROUGH REMAINS IN CONTROL WITH NORTHERN EXTENSION OF A HIGH PRESSURE SYSTEM AT THE SURFACE THAT SLIDE SOUTH BEHIND WEDNESDAYS BIG SYSTEM. NORTHERLY WINDS WILL BACK TO WESTERLY AS HEIGHTS BUILD THROUGH THE DAY BUT WE STILL ONLY GET TO 542DAM AT 500MB BY THURSDAY EVENING SO WE WILL NOT REALIZE THAT INCREASE AT THE SFC DURING DAYLIGHT HOURS. FRIDAY WE FIND OURSELVES IN BETWEEN THE EXITING HIGH AND A CLIPPER TRACKING EASTWARD OVER NORTHERN LAKE SUPERIOR. SW TO NE PRESSURE GRADIENT WILL SET UP GOOD SW FLOW AND WAA. LL JET AT 850MB WILL PEAK AROUND 45 KNOTS DURING THE AFTERNOON ALTHOUGH WE ONLY LOOK TO MIX UP TO AROUND 900MB. SHOULD STILL BE FAIRLY BREEZY OUT IN THE AFTERNOON WITH GUSTS REACHING 20-30 MPH. HIGHS SHOULD REACH INTO THE 40S ONCE AGAIN. THERE IS A SLIGHT CHANCE THAT A FEW RAIN/SNOW SHOWERS COULD POP UP LATE FRIDAY OR OVERNIGHT BUT THERE IS NOT MUCH MOISTURE IN THE COLUMN TO WORK WITH SO WILL CONTINUE TO LEAN TOWARD A DRY FORECAST. THIS CLIPPER WILL PULL A PAIR OF COLD FRONTS THROUGH THE REGION WHICH WILL CAUSE TEMPS TO DROP BOTH SATURDAY AND SUNDAY AS COLDER AND COLDER AIR WORKS INTO THE AREA. SAME HOLDS TRUE FOR SAT/SUN THAT MODELS ARE TRYING TO POP A FEW SHOWERS BUT DOMINATE AREA OF HIGH PRESSURE BUILDING IN FROM CANADA WILL CONTINUE TO KEEP VERY DRY AIR IN PLACE MAKING IT HARD FOR ANYTHING TO DEVELOP. EARLY NEXT WEEK IT LOOKS LIKE THE NORTHERN AND SOUTHERN STREAMS OF THE JETS WILL PHASE AGAIN PRODUCING ANOTHER STRONG LOW PRESSURE SYSTEM. ALL INDICATIONS AT THIS POINT ARE THAT THE STORM WILL DEVELOP MUCH FURTHER SOUTH AND EAST OF MI. MARINE... A STRONG LOW PRESSURE SYSTEM WILL DEEPEN AS IT TRACKS ALONG THE OHIO RIVER THROUGH THIS AFTERNOON. THE TRACK OF THE STORM PLACES THE EASTERN GREAT LAKES IN THE TIGHT NORTHEAST TO SOUTHWEST PRESSURE GRADIENT FIELD WHICH WILL RESULT IN GALE FORCE WINDS TODAY. GALE WARNINGS ARE IN EFFECT FOR LAKE HURON...LAKE ERIE AND LAKE ST CLAIR THROUGH THIS EVENING. SEE CURRENT MARINE HEADLINES FOR THE LATEST INFORMATION. A HIGH PRESSURE SYSTEM WILL THEN DROP THROUGH THE GREAT LAKES FROM CANADA ALLOWING THE WINDS TO SUBSIDE. YET ANOTHER LOW PRESSURE SYSTEM WILL MOVE ACROSS NORTHERN LAKE SUPERIOR ON FRIDAY BRING A RETURN OF MODERATE SOUTHWEST FLOW AND MILDER AIR. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...WINTER STORM WARNING...MIZ060-MIZ061-MIZ062-MIZ063-MIZ068-MIZ069- MIZ070-MIZ075-MIZ076-MIZ082-MIZ083...UNTIL 3 PM WEDNESDAY. WINTER WEATHER ADVISORY...MIZ053-MIZ054-MIZ055...UNTIL 3 PM WEDNESDAY. WIND ADVISORY...MIZ049-MIZ055...UNTIL 6 PM WEDNESDAY. LAKE HURON... GALE WARNING...LHZ363-LHZ421-LHZ422-LHZ441-LHZ442-LHZ443-LHZ462- LHZ463-LHZ464...UNTIL 8 PM WEDNESDAY. LAKE ST CLAIR... GALE WARNING...UNTIL 8 PM WEDNESDAY. MI WATERS OF LAKE ERIE... GALE WARNING...UNTIL 8 PM WEDNESDAY. && $$ AVIATION.....BT SHORT TERM...BT LONG TERM....DRK MARINE.......DRK YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1030 AM EDT WED MAR 12 2014 .SYNOPSIS...A DEEPENING AREA OF LOW PRESSURE OVER THE OHIO VALLEY WILL TRACK EAST-NORTHEASTWARD THROUGH THE MIDDLE ATLANTIC STATES TODAY...WITH ATTENDANT TRAILING COLD FRONT CROSSING CENTRAL NC THIS EVENING. HIGH PRESSURE WILL BUILD INTO THE AREA FOR THE REMAINDER OF THE WEEK. && .NEAR TERM /THROUGH TONIGHT/... AS OF 1030 AM WEDNESDAY... ...A WIND ADVISORY IS IN EFFECT FOR ALL OF CENTRAL NC FOR LATE THIS AFTERNOON THROUGH MIDNIGHT ... THINKING HAS NOT CHANGED MUCH REGARDING CONVECTIVE EVOLUTION AND STRONG WINDS THIS AFTERNOON AND EVENING. LIGHT PRECIP ASSOCIATED WITH A WEAKENING SOUTHERN STREAM WAVE LIGHTING ACROSS THE AREA IS MOVING OFF TO THE NORTHEAST AND WILL FOR THE MOST PART BE OUT OF THE CWA BY JUST AFTER NOON...LEAVING A PERIOD OF NO PRECIP AND POTENTIAL FOR SOME CLEARING/ADDITIONAL HEATING. REGIONAL VIS IMAGERY SHOWS WIDESPREAD CLOUD COVER UPSTREAM...THE WINDOW FOR BREAKS IN CLOUDS IS SHORT BEFORE THE STRONG COLD FRONT SWEEPS ACROSS THE AREA BETWEEN ROUGHLY 4PM AND 11PM. STRONG SOUTHWESTERLY PREFRONTAL WINDS AND 850MB TEMPS OF 10-12C SUPPORT HIGHS IN THE LOWER 70S WEST AND UPPER 70S EAST ONCE PRECIP MOVES OUT OF THE AREA. HAVE MADE SOME MINOR ADJUSTMENTS ACROSS THE NORTH AND NORTHWEST WHERE HEATING WILL BE SHORTEST. THE BIGGEST QUESTION REGARDING CONVECTION ALONG THE COLD FRONT IS DESTABILIZATION...WHICH APPEARS WILL BE SHALLOW AND CONFINED TO IMMEDIATELY ALONG AND AHEAD OF THE FRONT. THE LATEST RAP SHOWS MAYBE 200-400 J/KG OF SBCAPE AT BEST FROM CHARLOTTE TO ROXBORO AND DWINDLING WITH EASTWARD EXTENT. UNIDIRECTIONAL EFFECTIVE SHEAR WOULD SUPPORT A BROKEN LINE OF SHOWERS AND LOW-TOPPED STORMS...WITH BETTER COVERAGE CLOSER TO THE VIRGINIA BORDER WHERE FORCING AND MOISTURE ARE A LITTLE DEEPER. THE BIGGEST CONCERN TODAY WILL BE WINDS AHEAD OF AND BEHIND THE FRONT. INCREASED MIXING THIS AFTERNOON MAY ALLOW SOME OF THE 35- 40KT WIND BETWEEN 925MB AND 850MB TO REACH THE SURFACE...ESPECIALLY WITHIN SHOWERS/STORMS ALONG THE FRONT. THE STRONGEST WINDS WILL COME BEHIND THE FRONT WITH 10-12MB PRESSURE RISES (6HR) ASSOCIATED WITH THE DEEPENING 980MB LOW OVER THE MID-ATLANTIC. THERE IS SOME INHERENT UNCERTAINTY REGARDING NOCTURNAL STABILIZATION LIMITING WINDS...BUT THE STRENGTHENING PRESSURE GRADIENT AND SUBSIDENCE SHOULD AID IN GETTING 40-45KT DOWN TO THE SURFACE IN WHAT WILL BE A MOSTLY WELL-MIXED BOUNDARY LAYER. THUS THE WIND ADVISORY APPEARS TO BE WELL TIMED. LOWS TONIGHT WILL RANGE FROM THE MID-UPPER 20 NW TO LOWER-MID 30S SE. && .SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... AS OF 300 AM WEDNESDAY... AFTER SEVERAL DAYS OF SPRING-LIKE TEMPS...DEEP UPPER TROUGHING OVER THE EAST COAST ON THURSDAY WILL LEAD TO AN ABRUPT CHANGE BACK TO WINTER-LIKE TEMPS...AS HIGHS WILL ONLY BE IN THE 40S...A GOOD 15-20 DEGREES BELOW NORMAL. IN ADDITION...A STRONG GRADIENT BETWEEN THE DEPARTING SURFACE LOW AND THE HIGH BUILDING IN WILL RESULT IN BREEZY CONDITIONS...MAKING IT FEEL EVEN COLDER. THESE BREEZY WINDS...IN ADDITION TO DEWPOINTS IN THE SINGLE DIGITS RESULTING IN RELATIVE HUMIDITY VALUES IN THE TEENS...MAY CAUSE SOME FIRE WEATHER CONCERNS. CONTINUED COORDINATION WILL TAKE PLACE WITH THE FOREST SERVICE LATER THIS MORNING REGARDING THE NEED FOR ANY STATEMENTS. WINDS WILL RELAX THURSDAY NIGHT AS HIGH PRESSURE MOVES OVERHEAD AND WITH CLEAR SKIES...OVERNIGHT LOWS WILL FALL INTO THE MID 20S. THESE WELL BELOW NORMAL TEMPS WILL BE SHORT LIVED THOUGH AS WEAK SHORTWAVE RIDGING BUILDS EAST OVER THE AREA AND THE SURFACE HIGH SLIPS OFFSHORE (SETTING UP RETURN FLOW) ON FRIDAY. ALL OF THIS WILL RESULT IN TEMPS MODERATING INTO THE MID/UPPER 50S...WITH OVERNIGHT LOWS IN THE UPPER 30S TO LOWER 40S. && .LONG TERM /SATURDAY THROUGH TUESDAY/... AS OF 300 AM WEDNESDAY... A NORTHERN STREAM SHORT WAVE TROUGH WILL MOVE ACROSS THE GREAT LAKES AND INTO THE NEW ENGLAND AREA SATURDAY INTO SUNDAY...PROPELLING A COLD FRONT THROUGH OUR AREA LATE SATURDAY NIGHT INTO EARLY SUNDAY MORNING. HOWEVER...THERE CONTINUES TO BE DISAGREEMENT AMONG THE MODELS ON OUR PRECIP CHANCES. THE GFS CONTINUES TO BE THE WETTER MODEL AS IT SHOWS SOME SOUTHERN STREAM ENERGY ALSO TRANSLATING EAST DURING THIS TIME FRAME. THE ECMWF STILL IS VIRTUALLY DRY AS THE SOUTHERN STREAM ENERGY DOES NOT KICK EAST AS FAST. WILL MAINTAIN THE CURRENT FORECAST THINKING UNTIL MODELS COME INTO BETTER AGREEMENT. THEREFORE...WILL HOLD PRECIP CHANCES DOWN...WITH ONLY AN INCREASE IN CLOUD COVER. CONTINUED LOW LEVEL SOUTHERLY FLOW WILL RESULT IN MORE AIR MASS MODIFICATION...WITH HIGHS EXPECTED TO RISE INTO THE MID 60S ON SATURDAY. BRIEF NORTHERLY WINDS BEHIND THE FRONT EARLY ON SUNDAY SHOULD RESULT IN SLIGHTLY LOWER TEMPS...GENERALLY MORE IN THE WAY OF UPPER 50S TO LOWER 60S. CONFIDENCE DECREASES EVEN FURTHER FOR VERY END OF THE WEEKEND AND INTO EARLY NEXT WEEK...BUT THE GENERAL CONSENSUS IS THAT ANOTHER NORTHERN STREAM TROUGH WILL DIG INTO THE SOUTHEAST...WITH YET ANOTHER COASTAL LOW IMPACTING THE REGION AS SOUTHERN STREAM ENERGY MOVES EAST. GIVEN THE HANDLING OF THE SOUTHERN STREAM ENERGY EARLIER IN THE WEEKEND (SEE ABOVE PARAGRAPH)...IT IS NOT SURPRISING THAT THERE CONTINUES TO BE LARGE MODEL SPREAD. THE GFS IS NOT AS DEEP WITH THE NORTHERN STREAM TROUGH AND IS STILL INDICATING MUCH LESS PRECIP FOR CENTRAL NC SUNDAY INTO MONDAY. THE ECMWF SHOWS THE SOUTHERN STREAM ENERGY FINALLY KICKING EAST AND INDICATES A DEEPER TROUGH DIGGING ACROSS THE SOUTHEAST. THE RESULTANT SURFACE LOW TRACKS ACROSS THE SOUTHEAST AND EVENTUALLY OFF THE CAROLINA COAST LATE SUNDAY INTO MONDAY. WILL LEAN MORE TOWARDS THE ECMWF AS IT HAS BEEN THE MORE CONSISTENT MODEL (PER WPC) AND THEREFORE WILL SHOW INCREASING PRECIP CHANCES SUNDAY...WITH HIGHEST POPS CENTERED ON THE SUNDAY NIGHT/MONDAY TIME FRAME. THERE IS STILL A LOT TO BE IRONED OUT...GIVEN THIS IS DAYS 5/6...BUT IF THE ECMWF VERIFIES...IT COULD BE ANOTHER GOOD RAIN EVENT FOR CENTRAL NC. IN ADDITION...THERE WOULD BE A POSSIBILITY OF SOME WINTRY PRECIP (MOST LIKELY A CHANGEOVER TO SNOW AT THE TAIL END)...BUT GIVEN THE TIME OF YEAR AND THE NOT SO FAVORABLE POSITION/STRENGTH OF THE HIGH...WILL MAINTAIN AN ALL LIQUID FORECAST FOR NOW. TEMPS WILL BE NEAR NORMAL FOR MOST OF THE WEEKEND BEFORE FALLING BACK TO BELOW NORMAL EARLY NEXT WEEK. && .AVIATION /12Z WEDNESDAY THROUGH SUNDAY/... AS OF 735 AM WEDNESDAY... 24-HR TAF PERIOD: A QUICK MOVING SOUTHERN STREAM WAVE WILL TRAVERSE THE GULF COAST OVERNIGHT AND WILL MOVE OFF THE SOUTHEAST COAST THIS MORNING. MEANWHILE ACROSS THE CENTRAL US... AN INTENSIFYING LOW PRESSURE SYSTEM WILL TRACK FROM THE OH VALLEY ENE INTO THE MID-ATLANTIC REGION TODAY. MOISTURE WILL RAPIDLY SPREAD NEWD INTO THE AREA THIS MORNING IN ASSOC/W STRENGTHENING 35-40KT LLJ...WITH SCATTERED SHOWERS OVERSPREADING THE BETWEEN 12-15Z. COULD SEE A BRIEF PERIOD OF MVFR CEILINGS...BUT CEILINGS SHOULD REMAIN MOSTLY VFR. BY THE AFTERNOON AS THE BOUNDARY/MIXED LAYER DEEPENS AND GRADIENT INCREASES AS THE INTENSIFYING LOW MOVES INTO THE VIRGINIAS... STRONG SOUTHWESTERLY SURFACE WINDS WILL DEVELOPE...GUSTING TO 35 TO 40 MPH AT TIME. A STRONG COLD FRONT WILL SWEEP EASTWARD ACROSS CENTRAL NC BETWEEN 21Z-03Z. A BROKEN LINE OF SHOWERS...AND ISOLATED LOW-TOPPED THUNDERSTORMS WITH WIND GUSTS IN EXCESS OF 40KTS...WILL LIKELY ACCOMPANY THE COLD FRONT...FOLLOWED BY 35-40KTS OF POST-FRONTAL NORTHWESTERLY WINDS....WHICH COULD RESULT IN CROSSWIND IMPACTS FOR TERMINALS. LOOKING AHEAD: EXPECT PREDOMINATELY VFR CONDITIONS THROUGH SATURDAY. THE NEXT STORM COULD IMPACT THE AREA AS EARLY AS SUNDAY AND INTO EARLY NEXT WEEK. && .RAH WATCHES/WARNINGS/ADVISORIES... WIND ADVISORY FROM 3 PM THIS AFTERNOON TO MIDNIGHT EDT TONIGHT FOR NCZ007>011-021>028-038>043-073>078-083>086-088-089.. && $$ SYNOPSIS...MWS NEAR TERM...CBL/SMITH SHORT TERM...KRD LONG TERM...KRD AVIATION...CBL
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
754 AM EDT WED MAR 12 2014 .SYNOPSIS... A STRONG LATE-WINTER STORM WILL IMPACT THE AREA TODAY...FOLLOWED BY COLD AND BLUSTERY CONDITIONS WITH WELL-BELOW NORMAL TEMPERATURES FOR THURSDAY. TEMPERATURES WILL REBOUND TO NEAR SEASONAL LEVELS FRIDAY INTO THE WEEKEND...AHEAD OF A FRONTAL SYSTEM PUSHING SOUTHEAST FROM THE GREAT LAKES. THIS FRONT MAY PRODUCE SOME RAIN OR SNOW SHOWERS ON SATURDAY. && .NEAR TERM /THROUGH TONIGHT/... STRONG AND FAST MOVING STORM SYSTEM OVER WESTERN OHIO WILL SPREAD SNOW...RAIN...THUNDER AND PERHAPS SEVERE WEATHER TO OUR REGION LATER TODAY. TEMPERATURES IN NW WILL REMAIN IN LOW-MID 30S AND IN SOUTHEASTERN AREAS...THEY SHOULD TOP 60. STRONG BAROCLINIC ZONE. A FRONTAL BOUNDARY IS SAGGING INTO NORTHWESTERN PA WHICH WILL PRODUCE THE QUICK CHANGE OVER TO SNOW IN NW PENNSYLVANIA THIS MORNING. RADAR AND OBSERVATIONS SHOW SNOW OVER SOUTHERN MI AND OH. IMPLIED SNOW BANDS OVER LAKE ERIE. THE TRACK OF THE LOW WILL KEEP THE COLD AIR FROM PUSHING TOO DEEP INTO PENNSYLVANIA THIS MORNING AND EARLY AFTERNOON. THUS WSW FOR HEAVY SNOW CURRENTLY CONFINED TO NORTHWESTERN AREA. WITH ADVISORY TO SOUTH AND EAST AS COLD AIR FILTERS IN. MODELS SUGGEST FAST SYSTEM WITH RAIN AND POTENTIAL THUNDER LATER THIS AFTERNOON/EARLY EVENING IN CENTRAL AND SOUTHEASTERN AREAS. PREVIOUS DISCUSSION... COUPLED JET STRUCTURE STILL LOOKING LIKE A CLASSIC EXAMPLE...AND INTERACTION SHOULD DROP THE PRESSURE OF THE MAIN SFC LOW AS IT TRAVERSES THE PA TURNPIKE THROUGH THE LATE MORNING AND INTO THE EVENING. IT WILL TAKE IT/S OWN TOLL BY BRINGING MODERATE TO HEAVY RAIN TO MOST OF THE STATE TODAY...BUT RUC POINTS TO A LOWERING OF THE LI/S AND TRUE INSTABILITY ACROSS THE SRN THIRD/HALF OF THE AREA LATE THIS AFTN AND EARLY THIS EVENING. SPC HAS A SLIGHT RISK AREA COVERING THAT ROUGH AREA...AND HAVE ADDED GUSTY WIND WORDING TO THE GRIDS FOR THAT TIME FRAME - RIGHT AS THE LOW PASSES OVERHEAD. THE SNOW WILL BE HEAVIEST IN THE N IN THE MID DAY AND AFTERNOON. QPF IS IMPRESSIVE BUT MAY BE TAINTED BY CONVECTIVE FEEDBACK ON SOME MDL SOLUTIONS. STILL...THE OVERALL PICTURE OF 1-1.25 INCHES N AND 0.5-0.75 S IS LOOKING GOOD. THUS...WITH THE BULK OF THE PRECIP FALLING AS SNOW ALONG THE NY BORDER...ESP WARREN AND MCKEAN COS...THE GOING STORM TOTALS LOOK SOLID WITH 8-10 THERE. THE SNOW ACCUMULATION GRADIENT WILL BE TIGHT - ESP DURING THE DAYTIME - WITH ALMOST NO SNOW SOUTH OF ROUTE 6 IN THE MORNING AND NOT FAR S OF THE NRN TIER OF COS THIS AFTERNOON...DESPITE FALLING TEMPS. THE WARM AIR ALOFT IS JUST TOO MUCH AND SUN ANGLE NOW HIGH ENOUGH TO MAKE THE SNOW FORECAST A REAL TROUBLE. AS THE TEMPS GET COLD THIS AFTERNOON/EVENING...THERE IS A DANGER OF THE RAIN-WET ROADS BECOMING ICY QUICKLY AS THE PRECIP TYPE CHANGE OVER OCCURS FROM N TO S. THE SFC LOW SHOULD CONTINUE TO DEEPEN AS IT MOVES INTO NJ THIS EVENING. THE PRECIP SHOULD TAPER RATHER ABRUPTLY IN THE CENTRAL AND SERN ZONES THIS EVENING. BY 01Z...LITTLE IF ANY PRECIP IS LEFT THERE. SO BY THE TIME THE PROFILES GET COLD ENOUGH FOR SNOW THERE...IT SHOULD BE ENDING. WILL KEEP ALL SNOW TOTALS AND TIMING AS IS WITH JUST MINOR EDITING. THE WINDS WILL GET STRONG/GUSTY IN THE NORTHERN MTS LATE THIS MORNING...BUT THE PASSAGE OF THE LOW AND ANY STORMS IN THE SOUTH WILL KICK THEM UP THERE IN THE EARLY EVENING. && .SHORT TERM /THURSDAY/... MADE MINOR CHANGES TO GRIDS WITH OVERNIGHT LOWS MAINLY NEAR 0 IN NW TO TEENS SOUTHEAST. STILL FORECAST TO BE VERY COLD DAY. UPDATED GUIDANCE WAS SIMILAR TO PREVIOUS FORECAST. CHANGES WERE MINOR. PREVIOUS... THE SNOW SHOULD BE TAPERING OFF TO SCT SHSN IN THE EVENING ACROSS THE NRN AND WRN MTS...BUT WILL KEEP CURRENT TIMING ON WSW FLAGS TO ALLOW FOR LINGERING SNOW AND BLOWING SNOW PROBLEMS. LOW PRESSURE CONTINUES TO DEEPEN AS IT MOVES AWAY AND CREATES WIND PROBLEMS FOR THE LOCAL AREA. THE WINDS WILL GET FASTER ACROSS THE SRN HALF OF THE AREA TONIGHT AND SUSTAINED SPEEDS AND GUSTS MAY BOTH REACH WIND ADVY CRITERIA. HAVE THUS POSTED AN ADVY FOR THOSE AREAS THROUGH THURSDAY NOON. WHILE WINDS WILL BE STRONGEST THERE IN THE SOUTH...THE TEMPS DO NOT DROP FAST ENOUGH TO GET WIND CHILLS BELOW ADVY THE LINE OF -15F. WILL ISSUE AN ADVY FOR THE NW HALF AS THE CRITERIA SHOULD EASILY BE MET. IF THE TIMING OF THE SNOW WERE TO BE ENDING LATER THURS MORNING...WE MAY HAVE BEEN ABLE TO FORGO A WIND CHILL ADVY AND JUST WRAP IT INTO THE WSW. BUT THE CHILLS WILL LAST MUCH LONGER THAN THE ACCUMULATING SNOW...THROUGH THE ENTIRE MORNING...WHEREAS THE SNOW SHOULD BE VIRTUALLY DONE BY 2 AM/06Z. THURSDAY SHOULD BE ONE OF THE COLDEST WE HAVE SEEN YET THIS WINTER. THIS IS EVEN MORE IMPRESSIVE GIVEN THE MID-MARCH TIMING. 8H TEMPS DROP INTO THE MINUS 20S C IN THE MORNING...BUT THIS NASTINESS GETS DRAGGED THROUGH THE AREA RATHER QUICKLY DUE TO THE SHARPNESS OF THE TROUGH AND PROGRESSIVE NATURE OF THE FLOW ALOFT. LITTLE BREAKS IN THE CLOUDS OVER THE S/SE OVERNIGHT SHOULD LEAD TO GREATER BREAKS IN THE MORNING OVER THE SRN TIER AND SERN AREAS COULD CLEAR UP TOTALLY BY THE END OF THE MORNING. WILL PLAY IT MORE-CLOUDY THAN THAT FOR NOW. EVEN WITH THE SUN AND DOWNSLOPE...THE MAXES IN THE SE WILL ONLY BE IN THE M/U20S. THAT WOULD BE WELCOME IN THE NRN TIER WHERE MAXES MAY NOT MAKE IT INTO THE TWEENS /10-12F/. THE GUSTY WINDS WILL GRADUALLY SUBSIDE DURING THE DAY THURS WITH DAYTIME HIGHS 25-30F BELOW NORMAL. DAILY RECORD LOW/MINI-MAXES ARE IN JEOPARDY. IN ADDITION...LOW TEMPS THURS MORNING ACRS WRN PA WILL ALSO BE NEAR DAILY RECORD. SUFFICE IT TO SAY...IT MAY NOT BE THIS COLD AGAIN /ESPECIALLY DURING THE DAYLIGHT HOURS/ UNTIL NEXT WINTER. && .LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/... THE GOOD NEWS IS THAT THE COLD BLAST WILL BE SHORT-LIVED...WITH A RAPID MODERATION OCCURRING ON FRIDAY. BREEZY SW RETURN FLOW IN ADVANCE OF NRN CLIPPER SFC LOW TRACKING ACRS THE UPPER GREAT LAKES AND DOWNSLOPING SHOULD HELP TO BOOST TEMPS INTO THE 40S NORTH AND 50S SOUTH. THE MODELS TURN THE LOW TO THE NORTHEAST UP THE ST. LAWRENCE VLY ON DAY 5/SAT...DRAGGING A TRAILING/WEAK COLD FRONT ACRS THE NORTHEAST AND MID-ATL STATES. MODEL CONSENSUS INDICATES SOME LGT PCPN IS POSSIBLE WITH CHC POPS AS THE FRONT SHIFTS SEWD ACRS THE CWA. GEFS/EC ENSEMBLE MEANS SHOW THE LARGE SCALE PATTERN REVERTING BACK TO A WRN RIDGE/ERN TROUGH CONFIGURATION INTO EARLY NEXT WEEK. THIS HAS BEEN THE FAVORED/PREVAILING FLOW REGIME THIS WINTER...WITH A COLD POLAR VORTEX OVER EASTERN CANADA. A STRONG SFC HIGH PUSHING SEWD FROM THE UPPER MS VLY SHOULD DIRECT COLDER AIR INTO THE REGION BEHIND A REINFORCING FROPA ON SUNDAY...WITH TEMPS LKLY TRENDING LOWER BY DAY 7/MON. THE NON-NCEP OPRNL MODELS /12Z CMC AND ECMWF/ ARE MORE BULLISH ON CYCLOGENESIS INVOF THE GULF STREAM JUST EAST OF THE CAROLINAS...WITH THE NW EDGE OF POTNL PCPN SHIELD POSSIBLY REACHING SRN/SERN PA ON ST. PATRICK`S DAY. CONFIDENCE IS LOW GIVEN THE LARGE SPREAD BTWN THE GFS AND ECMWF/CMC. SOMETHING TO MONITOR IN THE DAYS TO COME. && .AVIATION /12Z WEDNESDAY THROUGH SUNDAY/... CONDITIONS NOW IFR ACROSS THE NW. STEADIER RAIN ACROSS THE NW. EXPECT CONDITIONS TO TO GO DOWN HILL ACROSS THE REST OF THE AREA...AS RAIN BECOMES MORE WIDESPREAD. THE BIG CONCERN IS STRONG WINDS AND LLWS...ALONG WITH HEAVY RAIN...AND PERHAPS SOME STRONG TO SEVERE THUNDERSTORMS ALONG THE MD LINE. ALSO SNOW ACROSS THE NORTH BY AFT. THEN TONIGHT THE CONCERN IS STILL STRONG WIND GUST...RAPID DROP IN TEMPS...AND MORE SNOW. THU WILL STILL FEATURE GUSTY WINDS...AS A DEEP STORM PULLS AWAY FROM THE AREA. OUTLOOK... THU...STRONG/GUSTY N/NW WINDS...GRADUALLY DIMINISHING IN THE AFTERNOON. FRI-SUN...NO SIG WX EXPECTED. && .HYDROLOGY... WITH WARMER TEMPERATURES RAINFALL TODAY...WE EXPECT MODERATE RISES ON RIVERS AND STREAMS. THERE IS STILL ENOUGH ICE IN SPOTS TO LEAD TO ICE JAMS...THOUGH SIGNIFICANT DECAY HAS OCCURRED AT MANY LOCATIONS DUE TO THE RECENTLY WARM WEATHER. ANY ICE JAMS WILL BE ISOLATED IN NATURE. MONITOR WATER LEVELS CLOSELY FOR THE REST OF THE WEEK. && .CTP WATCHES/WARNINGS/ADVISORIES... WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO NOON EDT THURSDAY FOR PAZ004>006-010>012-017-018-024-033-037-041-042. WINTER WEATHER ADVISORY FROM 3 PM THIS AFTERNOON TO 8 AM EDT THURSDAY FOR PAZ017-024-033. WIND ADVISORY FROM 5 PM THIS AFTERNOON TO NOON EDT THURSDAY FOR PAZ025>028-034>036-056>059-063>066. WINTER WEATHER ADVISORY UNTIL 8 AM EDT THURSDAY FOR PAZ006-010- 011-037. WINTER STORM WARNING UNTIL 8 AM EDT THURSDAY FOR PAZ004-005. && $$ SYNOPSIS...DANGELO/LA CORTE NEAR TERM...GRUMM/DANGELO SHORT TERM...GRUMM/DANGELO LONG TERM...STEINBUGL AVIATION...MARTIN HYDROLOGY...
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
742 AM EDT WED MAR 12 2014 .SYNOPSIS... A STRONG LATE-WINTER STORM WILL IMPACT THE AREA TODAY...FOLLOWED BY COLD AND BLUSTERY CONDITIONS WITH WELL-BELOW NORMAL TEMPERATURES FOR THURSDAY. TEMPERATURES WILL REBOUND TO NEAR SEASONAL LEVELS FRIDAY INTO THE WEEKEND...AHEAD OF A FRONTAL SYSTEM PUSHING SOUTHEAST FROM THE GREAT LAKES. THIS FRONT MAY PRODUCE SOME RAIN OR SNOW SHOWERS ON SATURDAY. && .NEAR TERM /THROUGH TONIGHT/... LOTS OF ACTION THIS PERIOD WITH RAIN ALREADY STRAFING THE NRN BORDER. MORE RADAR RETURN OVER CENTRAL OH ARE MOVING QUICKLY THIS WAY. THE FRONTAL BOUNDARY IS LAID OUT FROM PHL ALONG THE MASON- DIXON LINE TO KDAY AND KIND. SFC LOW IS CONSOLIDATING OVER THE WABASH AND IS ABOUT 995MB AT 08Z. GUSTS ON THE BACKSIDE OF THE LOW ARE ALREADY INTO THE 20S AND 30S. STRONG WARM ADVECTION OVER THE STATE IS KEEPING TEMPS IN THE 40S...EXCEPT ALONG THE NY BORDER WITH 30S NUDGING IN ON LIGHT N/NE WIND. DEWPOINTS HAVE RISEN SLIGHTLY AND ARE GENERALLY IN THE 30S. WET BULBS IN THE NRN MTS WILL STILL LIKELY YIELD RAIN AT FIRST...BUT NAM/RUC PROFILES DO MAKE IT MAINLY ISOTHERMAL FOR THE LOWEST FEW KFT THIS MORNING. THUS...IT COULD BE ANYTHING FOR THE FIRST FEW HOURS. THEN...IT GETS COLD AS PRECIP INTENSITY SHOULD PICK UP LATER THIS MORNING. COUPLED JET STRUCTURE STILL LOOKING LIKE A CLASSIC EXAMPLE...AND INTERACTION SHOULD DROP THE PRESSURE OF THE MAIN SFC LOW AS IT TRAVERSES THE PA TURNPIKE THROUGH THE LATE MORNING AND INTO THE EVENING. IT WILL TAKE IT/S OWN TOLL BY BRINGING MODERATE TO HEAVY RAIN TO MOST OF THE STATE TODAY...BUT RUC POINTS TO A LOWERING OF THE LI/S AND TRUE INSTABILITY ACROSS THE SRN THIRD/HALF OF THE AREA LATE THIS AFTN AND EARLY THIS EVENING. SPC HAS A SLIGHT RISK AREA COVERING THAT ROUGH AREA...AND HAVE ADDED GUSTY WIND WORDING TO THE GRIDS FOR THAT TIME FRAME - RIGHT AS THE LOW PASSES OVERHEAD. THE SNOW WILL BE HEAVIEST IN THE N IN THE MID DAY AND AFTERNOON. QPF IS IMPRESSIVE BUT MAY BE TAINTED BY CONVECTIVE FEEDBACK ON SOME MDL SOLUTIONS. STILL...THE OVERALL PICTURE OF 1-1.25 INCHES N AND 0.5-0.75 S IS LOOKING GOOD. THUS...WITH THE BULK OF THE PRECIP FALLING AS SNOW ALONG THE NY BORDER...ESP WARREN AND MCKEAN COS...THE GOING STORM TOTALS LOOK SOLID WITH 8-10 THERE. THE SNOW ACCUMULATION GRADIENT WILL BE TIGHT - ESP DURING THE DAYTIME - WITH ALMOST NO SNOW SOUTH OF ROUTE 6 IN THE MORNING AND NOT FAR S OF THE NRN TIER OF COS THIS AFTERNOON...DESPITE FALLING TEMPS. THE WARM AIR ALOFT IS JUST TOO MUCH AND SUN ANGLE NOW HIGH ENOUGH TO MAKE THE SNOW FORECAST A REAL TROUBLE. AS THE TEMPS GET COLD THIS AFTERNOON/EVENING...THERE IS A DANGER OF THE RAIN-WET ROADS BECOMING ICY QUICKLY AS THE PRECIP TYPE CHANGE OVER OCCURS FROM N TO S. THE SFC LOW SHOULD CONTINUE TO DEEPEN AS IT MOVES INTO NJ THIS EVENING. THE PRECIP SHOULD TAPER RATHER ABRUPTLY IN THE CENTRAL AND SERN ZONES THIS EVENING. BY 01Z...LITTLE IF ANY PRECIP IS LEFT THERE. SO BY THE TIME THE PROFILES GET COLD ENOUGH FOR SNOW THERE...IT SHOULD BE ENDING. WILL KEEP ALL SNOW TOTALS AND TIMING AS IS WITH JUST MINOR EDITING. THE WINDS WILL GET STRONG/GUSTY IN THE NORTHERN MTS LATE THIS MORNING...BUT THE PASSAGE OF THE LOW AND ANY STORMS IN THE SOUTH WILL KICK THEM UP THERE IN THE EARLY EVENING. && .SHORT TERM /THURSDAY/... THE SNOW SHOULD BE TAPERING OFF TO SCT SHSN IN THE EVENING ACROSS THE NRN AND WRN MTS...BUT WILL KEEP CURRENT TIMING ON WSW FLAGS TO ALLOW FOR LINGERING SNOW AND BLOWING SNOW PROBLEMS. LOW PRESSURE CONTINUES TO DEEPEN AS IT MOVES AWAY AND CREATES WIND PROBLEMS FOR THE LOCAL AREA. THE WINDS WILL GET FASTER ACROSS THE SRN HALF OF THE AREA TONIGHT AND SUSTAINED SPEEDS AND GUSTS MAY BOTH REACH WIND ADVY CRITERIA. HAVE THUS POSTED AN ADVY FOR THOSE AREAS THROUGH THURSDAY NOON. WHILE WINDS WILL BE STRONGEST THERE IN THE SOUTH...THE TEMPS DO NOT DROP FAST ENOUGH TO GET WIND CHILLS BELOW ADVY THE LINE OF -15F. WILL ISSUE AN ADVY FOR THE NW HALF AS THE CRITERIA SHOULD EASILY BE MET. IF THE TIMING OF THE SNOW WERE TO BE ENDING LATER THURS MORNING...WE MAY HAVE BEEN ABLE TO FORGO A WIND CHILL ADVY AND JUST WRAP IT INTO THE WSW. BUT THE CHILLS WILL LAST MUCH LONGER THAN THE ACCUMULATING SNOW...THROUGH THE ENTIRE MORNING...WHEREAS THE SNOW SHOULD BE VIRTUALLY DONE BY 2 AM/06Z. THURSDAY SHOULD BE ONE OF THE COLDEST WE HAVE SEEN YET THIS WINTER. THIS IS EVEN MORE IMPRESSIVE GIVEN THE MID-MARCH TIMING. 8H TEMPS DROP INTO THE MINUS 20S C IN THE MORNING...BUT THIS NASTINESS GETS DRAGGED THROUGH THE AREA RATHER QUICKLY DUE TO THE SHARPNESS OF THE TROUGH AND PROGRESSIVE NATURE OF THE FLOW ALOFT. LITTLE BREAKS IN THE CLOUDS OVER THE S/SE OVERNIGHT SHOULD LEAD TO GREATER BREAKS IN THE MORNING OVER THE SRN TIER AND SERN AREAS COULD CLEAR UP TOTALLY BY THE END OF THE MORNING. WILL PLAY IT MORE-CLOUDY THAN THAT FOR NOW. EVEN WITH THE SUN AND DOWNSLOPE...THE MAXES IN THE SE WILL ONLY BE IN THE M/U20S. THAT WOULD BE WELCOME IN THE NRN TIER WHERE MAXES MAY NOT MAKE IT INTO THE TWEENS /10-12F/. THE GUSTY WINDS WILL GRADUALLY SUBSIDE DURING THE DAY THURS WITH DAYTIME HIGHS 25-30F BELOW NORMAL. DAILY RECORD LOW/MINI-MAXES ARE IN JEOPARDY. IN ADDITION...LOW TEMPS THURS MORNING ACRS WRN PA WILL ALSO BE NEAR DAILY RECORD. SUFFICE IT TO SAY...IT MAY NOT BE THIS COLD AGAIN /ESPECIALLY DURING THE DAYLIGHT HOURS/ UNTIL NEXT WINTER. && .LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/... THE GOOD NEWS IS THAT THE COLD BLAST WILL BE SHORT-LIVED...WITH A RAPID MODERATION OCCURRING ON FRIDAY. BREEZY SW RETURN FLOW IN ADVANCE OF NRN CLIPPER SFC LOW TRACKING ACRS THE UPPER GREAT LAKES AND DOWNSLOPING SHOULD HELP TO BOOST TEMPS INTO THE 40S NORTH AND 50S SOUTH. THE MODELS TURN THE LOW TO THE NORTHEAST UP THE ST. LAWRENCE VLY ON DAY 5/SAT...DRAGGING A TRAILING/WEAK COLD FRONT ACRS THE NORTHEAST AND MID-ATL STATES. MODEL CONSENSUS INDICATES SOME LGT PCPN IS POSSIBLE WITH CHC POPS AS THE FRONT SHIFTS SEWD ACRS THE CWA. GEFS/EC ENSEMBLE MEANS SHOW THE LARGE SCALE PATTERN REVERTING BACK TO A WRN RIDGE/ERN TROUGH CONFIGURATION INTO EARLY NEXT WEEK. THIS HAS BEEN THE FAVORED/PREVAILING FLOW REGIME THIS WINTER...WITH A COLD POLAR VORTEX OVER EASTERN CANADA. A STRONG SFC HIGH PUSHING SEWD FROM THE UPPER MS VLY SHOULD DIRECT COLDER AIR INTO THE REGION BEHIND A REINFORCING FROPA ON SUNDAY...WITH TEMPS LKLY TRENDING LOWER BY DAY 7/MON. THE NON-NCEP OPRNL MODELS /12Z CMC AND ECMWF/ ARE MORE BULLISH ON CYCLOGENESIS INVOF THE GULF STREAM JUST EAST OF THE CAROLINAS...WITH THE NW EDGE OF POTNL PCPN SHIELD POSSIBLY REACHING SRN/SERN PA ON ST. PATRICK`S DAY. CONFIDENCE IS LOW GIVEN THE LARGE SPREAD BTWN THE GFS AND ECMWF/CMC. SOMETHING TO MONITOR IN THE DAYS TO COME. && .AVIATION /12Z WEDNESDAY THROUGH SUNDAY/... CONDITIONS NOW IFR ACROSS THE NW. STEADIER RAIN ACROSS THE NW. EXPECT CONDITIONS TO TO GO DOWN HILL ACROSS THE REST OF THE AREA...AS RAIN BECOMES MORE WIDESPREAD. THE BIG CONCERN IS STRONG WINDS AND LLWS...ALONG WITH HEAVY RAIN...AND PERHAPS SOME STRONG TO SEVERE THUNDERSTORMS ALONG THE MD LINE. ALSO SNOW ACROSS THE NORTH BY AFT. THEN TONIGHT THE CONCERN IS STILL STRONG WIND GUST...RAPID DROP IN TEMPS...AND MORE SNOW. THU WILL STILL FEATURE GUSTY WINDS...AS A DEEP STORM PULLS AWAY FROM THE AREA. OUTLOOK... THU...STRONG/GUSTY N/NW WINDS...GRADUALLY DIMINISHING IN THE AFTERNOON. FRI-SUN...NO SIG WX EXPECTED. && .HYDROLOGY... WITH WARMER TEMPERATURES RAINFALL TODAY...WE EXPECT MODERATE RISES ON RIVERS AND STREAMS. THERE IS STILL ENOUGH ICE IN SPOTS TO LEAD TO ICE JAMS...THOUGH SIGNIFICANT DECAY HAS OCCURRED AT MANY LOCATIONS DUE TO THE RECENTLY WARM WEATHER. ANY ICE JAMS WILL BE ISOLATED IN NATURE. MONITOR WATER LEVELS CLOSELY FOR THE REST OF THE WEEK. && .CTP WATCHES/WARNINGS/ADVISORIES... WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO NOON EDT THURSDAY FOR PAZ004>006-010>012-017-018-024-033-037-041-042. WINTER WEATHER ADVISORY FROM 3 PM THIS AFTERNOON TO 8 AM EDT THURSDAY FOR PAZ017-024-033. WIND ADVISORY FROM 5 PM THIS AFTERNOON TO NOON EDT THURSDAY FOR PAZ025>028-034>036-056>059-063>066. WINTER WEATHER ADVISORY UNTIL 8 AM EDT THURSDAY FOR PAZ006-010- 011-037. WINTER STORM WARNING UNTIL 8 AM EDT THURSDAY FOR PAZ004-005. && $$ SYNOPSIS...DANGELO/LA CORTE NEAR TERM...DANGELO SHORT TERM...DANGELO LONG TERM...STEINBUGL AVIATION...MARTIN HYDROLOGY...CR
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
1113 AM EDT WED MAR 12 2014 .SYNOPSIS... A COLD FRONT WILL PUSH THROUGH THE FORECAST AREA TODAY WITH COOL HIGH PRESSURE BUILDING IN ON THURSDAY. THE AIRMASS WILL SLOWLY MODERATE WARMER INTO SATURDAY...BEFORE A BROAD AND COLDER UPPER LEVEL TROF BUILDS IN SUNDAY THROUGH MONDAY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 1110 AM...LOW CLOUDS ARE HOLDING ON A LITTLE LONGER THAN EXPECTED OVER THE FOOTHILLS AND PIEDMONT OF THE WRN CAROLINAS AND NE GA THIS MORNING. AND THE LATEST NAM HAS COME IN WITH IT/S GREATEST INSTABILITY JUST A LITTLE EAST OF THE FORECAST AREA AROUND 21 UTC THIS AFTN. THERE IS STILL A LINE FINE OVER ERN TN WHICH REPRESENTS THE SFC COLD FRONT. CONVECTION IS SLOWLY STRENGTHENING ALONG THE NRN PORTION OF THE LINE WHERE THERE IS GREATER FORCING...BUT THE SOUTHERN END SHOULDN/T DEVELOP INTO DEEP CONVECTION UNTIL IT GETS EAST OF THE MOUNTAINS. THE THINKING NOW IS THAT IT WILL STEADILY STRENGTHEN ONCE EAST OF THE MOUNTAINS...BUT THAT THE GREATEST SEVERE POTENTIAL WILL BE A LITTLE EAST OF THE FORECAST AREA. STILL...THE I77 CORRIDOR IS THE AREA MOST UNDER THE GUN THIS AFTN IN OUR FA. ALSO...WINDS IN THE BNDRY LAYER JUST BEHIND THE LINE ARE QUITE STRONG...AND EVEN A RELATIVELY WEAK LINE OF SHOWERS HAS THE POTENTIAL TO PRODUCE DAMAGING WINDS. OVER THE UPSTATE AND NE GA THE ATMOSPHERE LOOKS MORE CAPPED...THOUGH DEWPOINTS WILL BE A LITTLE HIGHER. OVERALL...THE HRRR TREND OF THE LINE OF CONVECTION NOT DEVELOPING VERY FAR INTO THE UPSTATE LOOKS GOOD AND HAS BEEN REFLECTED IN THE GRIDS. BUT EVEN HERE 40 KT GRADIENT WIND GUSTS ARE POSSIBLE AND THE WIND ADVISORY STILL LOOKS VALID. AS OF 630 AM...I WILL UPDATE THE FORECAST WITH THE RECENT OBSERVATIONS ACROSS THE FORECAST AREA. IN ADDITION...I WILL INCREASE POPS EARLY THIS MORNING...BASED OFF OF THE RECENT RADAR DATA. IN ADDITION...I WILL ADD TIMING AND PLACEMENT DETAILS FOR A LINE OF TSRA TO SWEEP ACROSS THE NRN I-77 CORRIDOR THIS AFTERNOON. AS OF 415 AM...A VERY COMPLICATED WEATHER EVENT IN THE OFFING. THE LATEST RADAR IMAGES INDICATED THAT WIDESPREAD LIGHT RAIN WAS SPREADING NORTH ACROSS NE GA AND THE WESTERN CAROLINAS. NAM INDICATES THAT 305-315K ISENTROPIC LIFT WILL INCREASE THROUGH DAYBREAK...THEN BECOMES SCT DURING THE REST OF THE DAY. HOWEVER...A FIELD OF MID LEVEL Q-VECTOR CONVERGENCE WILL SLIDE ACROSS THE FORECAST AREA FROM MID DAY THROUGH SUNSET. I WILL INCREASE POPS TO CATE ACROSS THE MTNS AND FOOTHILLS THROUGH MID DAY. A STRONG COLD FRONT IS EXPECTED TO SWEEP WEST TO EAST BETWEEN 21-00Z. THE STRONG...COLD...MOIST NW H85 WINDS WILL REMAIN ACROSS THE NC MTNS THROUGH TONIGHT. SOUTHWEST WINDS WILL INCREASE ACROSS THE CWA AHEAD OF THE APPROACHING COLD FRONT. THIS AFTERNOON...WINDS ACROSS THE FOOTHILLS AND PIEDMONT WILL INCREASE TO 20 TO 25KTS WITH GUSTS ABOVE 40 KTS DURING THE LATE AFTERNOON AND EVENING. ACROSS THE MTNS...WINDS WILL ALSO INCREASE SHARPLY DURING THE MID DAY. HOWEVER...BOTH THE NAM AND GFS INDICATE THAT H85 WINDS WILL REACH 50-55 KTS BETWEEN 0-6Z. I WILL HIGHLIGHT THE FOOTHILLS AND PIEDMONT WITH A WIND ADVISORY FROM NOON THROUGH MIDNIGHT. ACROSS THE MTNS...THE ADVISORY WILL HIGHLIGHT THE NOON TO 6 AM PERIOD. NRN MTN AREAS WILL SEE GUSTS AROUND 50KTS...HIGHLIGHT WITH A HIGH WIND WARNING FROM NOON TO 6 AM. THE ENVIRONMENT ALONG AND AHEAD OF THE COLD FRONT WILL BE A HIGH SHEAR AND LOW CAPE ENVIRONMENT. THE 0-1 KM HELICITY AHEAD OF THE FRONT ARE FORECAST TO RANGE FROM 250-300 M2/S2. FORECAST SOUNDINGS INDICATE A THIN LAYER OF CAPE BETWEEN 250-300 J/KG. THE GREATEST 0-3 KM EHI...APPROACHING .8 M2/S2...IS EXPECTED TO OCCUR ALONG AND EAST OF THE I-77 CORRIDOR DURING THE LATE AFTERNOON. IN ADDITION...SHERB VALUES WITHIN THE I-77 CORRIDOR IS FORECAST TO EXCEED 1 AROUND 21Z. IT APPEARS THAT A QLCS SVR WIND EVENT MAY OCCUR ACROSS THE I-77 CORRIDOR LATE THIS AFTERNOON. THE SVR TSRA THREAT WILL BE HIGHLIGHTED IN THE HWO. TONIGHT...H85 TEMPERATURES WILL RAPIDLY COOL TO -10 TO -14 C ACROSS THE TN BORDER COUNTIES. THE COMBINATION OF STRONG NW WINDS AND DEEP MOISTURE SHOULD SUPPORT SHSN ALONG THE WESTERN SLOPES OF THE SOUTHERN APPALACHIANS THROUGH TONIGHT. IN ADDITION...WEAK INSTABILITY MAY LINGER WITHIN THE LLVL NW FLOW DURING THE MID EVENING...SUPPORTING MOD SHSN. MIN TEMPERATURES ARE FORECAST TO RANGE FROM THE TEENS TO THE L20S ACROSS THE MTNS...NEAR 30 EAST. THE COLD TEMPERATURES SHOULD YIELD SNOW RATIOS AT LEAST 20 TO 1. EVENT SNOWFALL ACROSS THE TN BORDER COUNTIES IS FORECAST TO RANGE FROM 2-3 INCHES...WILL HIGHLIGHT WITH A WINTER WEATHER ADVISORY. && .SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... AS OF 330 AM WEDNESDAY...STRONG CHANNELED SHORT WAVE CROSSES THE AREA THURSDAY AS AN UPPER TROF MOVES EAST OF THE AREA. ANY LINGERING MTN SNOW SHOWERS WILL DISSIPATE QUICKLY THU MORNING AS LOW LEVEL DRIES UP. TIGHT PRESSURE GRADIENT WILL RELAX THRU THE DAY AS HIGH PRESSURE BUILDS INTO THE AREA. HOWEVER...GUSTY WINDS COULD LINGER THROUGH THE MORNING. VERY LOW RH IS LIKELY AS THE AIR MASS MOVING INTO THE AREA IS VERY DRY. THERE IS SOME CONCERN ON THURSDAY THAT PORTIONS OF THE FCST AREA WILL FLIRT WITH RED FLAG FIRE CONDITIONS BECAUSE OF THE VERY LOW RH IN THE AFTERNOON AND POTENTIALLY LINGERING WIND GUSTS OVER THE MTNS. EXPECT HIGHS 10 TO 15 DEGREES BELOW NORMAL. ZONAL FLOW DEVELOPS THU NITE AND CONTINUES FRI AND FRI NITE. SOME WEAK SHORT WAVES MOVE ACROSS THE AREA THRU THE ZONAL FLOW. AT THE SFC...THE HIGH PRESSURE CENTER MOVES OVER THE AREA THU NITE THEN OFF SHORE FRI. A WEAK FRONTAL SYSTEM DROPS INTO THE OH VALLEY FRI NITE AS A LOW PRESSURE CENTER MOVES INTO THE SRN PLAINS. MOISTURE RETURNS ACROSS THE AREA IN THE DEVELOPING SLY FLOW AS THE HIGH MOVES OFF SHORE. EXPECT MAINLY CLOUDS FROM THIS RETURN MOISTURE. PRECIP SHOULD HOLD OFF UNTIL AFTER FRI NITE. HIGHS FRI WILL RISE TO NEAR NORMAL. LOWS THU NITE AROUND 10 DEGREES BELOW NORMAL WILL RISE A LITTLE ABOVE NORMAL FRI NITE. && .LONG TERM /SATURDAY THROUGH TUESDAY/... AS OF 145 AM EDT WED...THERE IS STILL MUCH UNCERTAINTY IN THE EXT RANGE FCST. THE ULVL PATTERN/ENERGY AND MASS FIELDS ARE NOT WELL AGREED UPON WHICH LEADS TO VARYING SFC SENSIBLE WX SOLNS BTW THE MAIN OP MODELS. THE INCOMING COLD FRONT SAT IS MORE PRONOUNCED AND HAS GREATER GOM MOISTURE FLUX THAN THE CWC/ECMWF. HOWEVER...THERE IS DECENT AGREEMENT WITH THE LLVL THERMAL FIELDS AND WILL COUNT ON MAINLY ALL RAIN IN ISENT WARM SECTOR LIFT. THERE COULD BE BRIEF -SNSH ACROSS THE HIGHEST NC MTN TERRAIN WITH NO SIGFNT ACCUMS THROUGH 14Z SAT. THE BIGGER DIFFERENCE IN THE MODELS OCCURS SUN THROUGH TUE WITH THE EVOLUTION OF THE AFOREMENTIONED SFC BOUNDARY. WHILE THE GFS IS MAINTAINING NEARLY UNIFORM FLOW THROUGH A DEEP LAYER AND THUS A NEARLY STATIONARY COASTAL SFC FRONT...THE ECMWF AND CMC DEVELOP A STRONG ULVL TROF AND COASTAL MILLER/A CYCLOGENESIS SUN NIGHT. THIS LATTER SCENARIO WOULD BRING IN MUCH GREATER MOISTURE AND ALONG WITH SOME MEASURE OF LOWERING PARTIAL THICKNESSES AND DIURNAL COOLING...SN OR A RA/SN MIX SUN AND MON NIGHTS. THIS IDEA WAS GIVEN A LITTLE MORE WEIGHT THAN THE TOTALLY SUPPRESSED AND DRY GFS SOLN. THE GOING MID CHANCE POPS STILL LOOK GOOD SUN NIGHT THROUGH MON NIGHT WITH SNOW ACCUMS ACROSS THE NC MTNS EARLY MON AND PERHAPS LOW END ACCUMULATING SNOW INTO THE NC FOOTHILLS AND PIEDMONT MON NIGHT. TEMPS WILL BEGIN THE PERIOD RIGHT AROUND NORMAL AND LIKELY DROP TO 8-10 DEGREES BELOW NORMAL BY MON WITH WINDS SHIFTING NE/LY AS A CANADIAN HIGH BUILDS TO THE NORTH AND A BROAD ULVL TROF DEVELOPS OVER THE ERN CONUS. && .AVIATION /15Z WEDNESDAY THROUGH SUNDAY/... AT KCLT...THE CENTER OF 990 MB LOW WILL TRACK FROM THE OHIO RIVER VALLEY TO THE NEW ENGLAND COAST THROUGH THE TAF PERIOD. LLVL LIFT AND DEEP MOISTURE WILL SWEEP NORTH AHEAD OF APPROACHING COLD FRONT THIS MORNING AND AFTERNOON. -SHRA WITH IFR CEILINGS IS EXPECTED DURING THE EARLY MORNING DAYLIGHT HOURS. FROPA IS EXPECTED BETWEEN 22-02Z ACROSS THE TERMINAL. AS THE FRONT APPROACHES...SW WILL STRENGTHEN THROUGH THE AFTERNOON...WITH GUSTS NEAR 40 KTS. IN THE WAKE OF THE FRONT...WIND WILL VEER FROM THE NW WITH GUSTS IN THE MID TO UPPER 30 KTS. ELSEWHERE...IFR CEILINGS AND -SHRA WILL INCREASE AHEAD OF AN APPROACHING COLD FRONT THIS MORNING. BY MID DAY...VFR CONDITIONS WITH SW WINDS STRENGTHENING SIGNIFICANTLY...WITH GUSTS IN THE MID TO UPPER 30 KTS. IN THE WAKE OF THE FRONT...WIND WILL VEER FROM THE NW WITH GUSTS IN THE MID TO UPPER 30 KTS. OUTLOOK...DRY HIGH PRESSURE WILL REMAIN OVER THE WESTERN CAROLINAS THROUGH THE REMAINDER OF THE WORK WEEK. CONFIDENCE TABLE... 15-21Z 21-03Z 03-09Z 09-15Z KCLT MED 77% HIGH 100% HIGH 100% HIGH 100% KGSP HIGH 87% HIGH 100% HIGH 100% HIGH 100% KAVL LOW 58% HIGH 88% HIGH 100% HIGH 100% KHKY HIGH 82% HIGH 100% HIGH 100% HIGH 100% KGMU HIGH 86% HIGH 100% HIGH 100% HIGH 100% KAND MED 65% HIGH 100% HIGH 100% HIGH 100% THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE) WWW.WEATHER.GOV/GSP/AVIATION_TABLES && .GSP WATCHES/WARNINGS/ADVISORIES... GA...WIND ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR GAZ010-017-018- 026-028-029. NC...WIND ADVISORY UNTIL 6 AM EDT THURSDAY FOR NCZ048-051>053-058- 059-062>065-501-503-505-507-509. WIND ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR NCZ035>037-056- 057-068>072-082-502-504-506-508-510. WINTER WEATHER ADVISORY FROM 6 PM THIS EVENING TO 6 AM EDT THURSDAY FOR NCZ033-048>052-058. HIGH WIND WARNING UNTIL 6 AM EDT THURSDAY FOR NCZ033-049-050. SC...WIND ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR SCZ001>014-019. && $$ SYNOPSIS...SBK NEAR TERM...MCAVOY/NED SHORT TERM...RWH LONG TERM...SBK AVIATION...NED
AREA FORECAST DISCUSSION...UPDATED
NWS MORRISTOWN TN
957 AM EDT WED MAR 12 2014 .DISCUSSION... A BAND OF SHOWERS MARKS THE POSITION OF THE COLD FRONT...WHICH HAS MOVED TO THE EAST OF OHX. TIMING OF THE FRONT BRINGS IT THROUGH OUR AREA BETWEEN 15Z AND 19Z. BEHIND THE FRONT...NO PRECIP APPEARS ON RADAR...AND THIS TIMING LINES UP WELL WITH THE RUC AND NAM DEPICTIONS OF DRYING ALOFT. AS A RESULT...WILL SPEED UP THE DECREASE IN POPS THIS AFTERNOON. SOME LOW LEVEL MOISTURE AND UPSLOPE NW FLOW WILL KEEP SOME CHANCE POPS GOING IN THE HIGHER ELEVATIONS. ALTHOUGH CURRENTLY THE WINDS ACROSS THE AREA ARE BELOW ADVISORY CRITERIA...BETWEEN 10 AND 20 MPH WITH GUSTS TO 25 MPH...OBS BEHIND THE FRONT SHOW STRONGER WINDS WILL ARRIVE THIS AFTERNOON. THE WIND ADVISORY WILL BE LEFT UNCHANGED. && .PRELIMINARY POINT TEMPS/POPS... CHATTANOOGA AIRPORT, TN 67 28 49 32 / 80 10 0 0 KNOXVILLE MCGHEE TYSON AIRPORT, TN 68 25 43 32 / 90 60 0 0 OAK RIDGE, TN 66 25 43 32 / 80 40 0 0 TRI CITIES AIRPORT, TN 65 21 38 26 / 90 60 20 0 && .MRX WATCHES/WARNINGS/ADVISORIES... NC...WIND ADVISORY UNTIL 11 PM EDT THIS EVENING FOR CHEROKEE-CLAY. TN...WINTER WEATHER ADVISORY FROM 6 PM THIS EVENING TO 4 AM EDT THURSDAY FOR BLOUNT SMOKY MOUNTAINS-COCKE SMOKY MOUNTAINS- JOHNSON-SEVIER SMOKY MOUNTAINS-SOUTHEAST CARTER-SOUTHEAST GREENE-SOUTHEAST MONROE-UNICOI. WIND ADVISORY UNTIL 11 PM EDT /10 PM CDT/ THIS EVENING FOR ANDERSON-BLEDSOE-BLOUNT SMOKY MOUNTAINS-BRADLEY-CAMPBELL- CLAIBORNE-COCKE SMOKY MOUNTAINS-EAST POLK-GRAINGER-HAMBLEN- HAMILTON-HANCOCK-HAWKINS-JEFFERSON-JOHNSON-KNOX-LOUDON- MARION-MCMINN-MEIGS-MORGAN-NW BLOUNT-NORTH SEVIER-NORTHWEST CARTER-NORTHWEST COCKE-NORTHWEST GREENE-NORTHWEST MONROE- RHEA-ROANE-SCOTT TN-SEQUATCHIE-SEVIER SMOKY MOUNTAINS- SOUTHEAST CARTER-SOUTHEAST GREENE-SOUTHEAST MONROE-SULLIVAN- UNICOI-UNION-WASHINGTON TN-WEST POLK. VA...WINTER WEATHER ADVISORY FROM 6 PM THIS EVENING TO 4 AM EDT THURSDAY FOR WISE. WIND ADVISORY UNTIL 11 PM EDT THIS EVENING FOR LEE-RUSSELL-SCOTT- WASHINGTON-WISE. && $$ DGS
AREA FORECAST DISCUSSION
NWS SAN JOAQUIN VALLEY - HANFORD CA
250 PM PDT WED MAR 12 2014 .UPDATE... ADDED SLIGHT CHANCE OF SHOWERS TO THE SOUTHERN SIERRA NEVADA THIS AFTERNOON AND EVENING. && .SYNOPSIS... FEW CLOUDS AND ABOVE NORMAL TEMPERATURES ARE EXPECTED THROUGH MONDAY. AFTERNOONS WILL BE WARMEST SUNDAY AND MONDAY AND WILL APPROACH RECORD LEVELS IN THE SAN JOAQUIN VALLEY AND NEARBY FOOTHILLS. A WEAK LOW PRESSURE SYSTEM WILL APPROACH TUESDAY PUSHING TEMPERATURES BACK DOWN BUT STILL REMAINING ABOVE NORMAL. && .DISCUSSION... UPSLOPE CLOUDS HAVE DEVELOPED OVER THE EAST SLOPES OF THE SOUTHERN SIERRA NEVADA THIS AFTERNOON DUE TO FAVORABLE OROGRAPHICS IN THE EASTERLY FLOW ALOFT. CUMULUS CLOUDS HAVE SPILLED OVER THE CREST INTO THE HIGH COUNTRY...AND HANFORD DOPPLER RADAR HAS DETECTED POSSIBLE ISOLATED SHOWERS NEAR GIANT FOREST. PER DISCUSSION WITH WFO LAS VEGAS...HAVE ADDED A SLIGHT CHANCE OF SHOWERS OVER THE HIGH COUNTRY IN FRESNO AND NORTHERN TULARE COUNTIES FOR THE REMAINDER OF THIS AFTERNOON AND THIS EVENING. && .AVIATION... WINDS WILL BE DECREASING ACROSS THE REGION THIS AFTERNOON AND BY 03Z WILL BE PRIMARILY TERRAIN DRIVEN. NON IMPACTFUL WINDS EXPECTED THURSDAY ALL AREAS. FEW TO SCT CLOUDS NEAR 10KFT AND LOCALIZED MVFR CEILINGS IN THE SIERRA MOUNTAINS AND FOOTHILLS DURING THE AFTERNOON HOURS. && .PREV DISC... /ISSUED 126 PM PDT WED MAR 12 2014/ DISCUSSION... WIND EVENT IS QUICKLY WINDING DOWN ACROSS OUR FORECAST AREA PRETTY MUCH AS EXPECTED. ISOLATED ADVISORY LEVEL GUST STILL POSSIBLE THROUGH 2 PM BUT THE TREND IS DEFINITELY DOWN FOR THE REST OF THE AFTERNOON PER HRRR WIND GRIDS AND MODELED MASS/THERMAL FIELDS. PEAK WIND GUSTS WERE NEAR 50 MPH IN YOSEMITE NP AND IN THE 50S THROUGH THE PASSES OF CENTRAL KERN COUNTY. OTHER INTERESTING FEATURE WAS PATCH OF MID CLOUDS THAT DEVELOPED THIS MORNING AND ARE STILL IN THE PROCESS OF DECAYING. THIS WAS LIKELY DUE TO STRONG EASTERLY FLOW JUST ABOVE THE STABLE LAYER OVER THE SJV CAUSING ENOUGH UPWARD MOVEMENT TO SATURATE THE AIR PARCELS. REALLY GOOD AGREEMENT BETWEEN DETERMINISTIC/ENSEMBLE DATA THROUGH THE WEEKEND AS H5 RIDGE POPS OVER CALIFORNIA. CENTRAL HEIGHTS VARY BUT TIME-AVERAGED DETERMINISTIC GFS PEAKS AT ABOUT 586DM WHICH IS ABOUT 2 STANDARD DEVIATIONS ABOVE CLIMO. THERMAL FIELDS SHOW PERTURBATIONS OF SIMILAR STRENGTH ALL PEAKING SUNDAY /WITH LASTING EFFECTS INTO MONDAY/. LOCAL BIAS-CORRECTED DATA SUGGEST WIDESPREAD 80S ARE IN THE CARDS FOR THE SJV AND LOWER FOOTHILLS SUN-MON WITH SOME 90S EVEN POSSIBLE. THIS IS WELL ABOVE NORMAL /UPPER 60S/ AND APPROACHING RECORD VALUES /SEE WEATHER STORY GRAPHIC ON OUR WEBSITE/. FOR NOW IT APPEARS THE SPRING HEAT WILL BE SHORT LIVED AS A WEAK SHORTWAVE WILL IMPINGE ON THE WESTERN PERIPHERY OF THE ANTI-CYCLONE AND NUDGE IT EASTWARD. QUITE A BIT OF SPREAD IN THE MODEL DATA FOR THIS SHORTWAVE REGARDING STRENGTH/TIMING...THOUGH THAT ISN/T UNUSUAL FOR SOMETHING SEVEN DAYS OUT. MEAN ENSEMBLE DATA HOWEVER DO SUPPORT A TROUGH COMING IN MID-WEEK WHICH WILL SUPPRESS TEMPERATURES A BIT /THOUGH STILL ABOVE AVERAGE/ AND BRING ABOUT A SLIGHT CHANCE OF PRECIPITATION /OPTED FOR NEAR CLIMO POPS/. FWIW THE DETERMINISTIC GFS IS TRENDING A LITTLE DEEPER WITH THE SYSTEM WHILE THE TIMING HAS REMAINED FAIRLY STEADY. REGARDLESS IT DOESN/T LOOK LIKE A LARGE PRECIP MAKER AT ALL. && .AIR QUALITY ISSUES... NONE. && .CERTAINTY... THE LEVEL OF CERTAINTY FOR DAYS 1 AND 2 IS HIGH. THE LEVEL OF CERTAINTY FOR DAYS 3 THROUGH 7 IS HIGH. THIS INFORMATION IS PROVIDED AS PART OF A TRIAL PROJECT CONDUCTED BY THE NATIONAL WEATHER SERVICE SAN JOAQUIN VALLEY - HANFORD. CERTAINTY LEVELS INCLUDE LOW...MEDIUM...AND HIGH. PLEASE VISIT WWW.WEATHER.GOV/HNX/CERTAINTY.PHP /ALL LOWER CASE/ FOR ADDITIONAL INFORMATION AND/OR TO PROVIDE FEEDBACK. && .CLIMATE... RECORDS SITE DATE HI_MAX:YEAR LO_MAX:YEAR HI_MIN:YEAR LO_MIN:YEAR KFAT 03-12 84:1910 50:1952 55:2005 28:1950 KFAT 03-13 84:2007 53:1981 59:1932 31:1950 KFAT 03-14 83:2007 48:1975 55:1995 29:1944 KBFL 03-12 88:1910 51:2006 56:1979 25:1907 KBFL 03-13 88:2007 53:1969 59:1979 21:1907 KBFL 03-14 88:1916 53:1944 62:1900 28:1907 && .HNX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ PUBLIC...SANGER AVN/FW...INIGUEZ PREV DISCUSSION...INIGUEZ SYNOPSIS...INIGUEZ WEATHER.GOV/HANFORD
AREA FORECAST DISCUSSION
NWS SAN JOAQUIN VALLEY - HANFORD CA
126 PM PDT WED MAR 12 2014 .SYNOPSIS... FEW CLOUDS AND ABOVE NORMAL TEMPERATURES ARE EXPECTED THROUGH MONDAY. AFTERNOONS WILL BE WARMEST SUNDAY AND MONDAY AND WILL APPROACH RECORD LEVELS IN THE SAN JOAQUIN VALLEY AND NEARBY FOOTHILLS. A WEAK LOW PRESSURE SYSTEM WILL APPROACH TUESDAY PUSHING TEMPERATURES BACK DOWN BUT STILL REMAINING ABOVE NORMAL. && .DISCUSSION... WIND EVENT IS QUICKLY WINDING DOWN ACROSS OUR FORECAST AREA PRETTY MUCH AS EXPECTED. ISOLATED ADVISORY LEVEL GUST STILL POSSIBLE THROUGH 2 PM BUT THE TREND IS DEFINITELY DOWN FOR THE REST OF THE AFTERNOON PER HRRR WIND GRIDS AND MODELED MASS/THERMAL FIELDS. PEAK WIND GUSTS WERE NEAR 50 MPH IN YOSEMITE NP AND IN THE 50S THROUGH THE PASSES OF CENTRAL KERN COUNTY. OTHER INTERESTING FEATURE WAS PATCH OF MID CLOUDS THAT DEVELOPED THIS MORNING AND ARE STILL IN THE PROCESS OF DECAYING. THIS WAS LIKELY DUE TO STRONG EASTERLY FLOW JUST ABOVE THE STABLE LAYER OVER THE SJV CAUSING ENOUGH UPWARD MOVEMENT TO SATURATE THE AIR PARCELS. REALLY GOOD AGREEMENT BETWEEN DETERMINISTIC/ENSEMBLE DATA THROUGH THE WEEKEND AS H5 RIDGE POPS OVER CALIFORNIA. CENTRAL HEIGHTS VARY BUT TIME-AVERAGED DETERMINISTIC GFS PEAKS AT ABOUT 586DM WHICH IS ABOUT 2 STANDARD DEVIATIONS ABOVE CLIMO. THERMAL FIELDS SHOW PERTURBATIONS OF SIMILAR STRENGTH ALL PEAKING SUNDAY /WITH LASTING EFFECTS INTO MONDAY/. LOCAL BIAS-CORRECTED DATA SUGGEST WIDESPREAD 80S ARE IN THE CARDS FOR THE SJV AND LOWER FOOTHILLS SUN-MON WITH SOME 90S EVEN POSSIBLE. THIS IS WELL ABOVE NORMAL /UPPER 60S/ AND APPROACHING RECORD VALUES /SEE WEATHER STORY GRAPHIC ON OUR WEBSITE/. FOR NOW IT APPEARS THE SPRING HEAT WILL BE SHORT LIVED AS A WEAK SHORTWAVE WILL IMPINGE ON THE WESTERN PERIPHERY OF THE ANTI-CYCLONE AND NUDGE IT EASTWARD. QUITE A BIT OF SPREAD IN THE MODEL DATA FOR THIS SHORTWAVE REGARDING STRENGTH/TIMING...THOUGH THAT ISN/T UNUSUAL FOR SOMETHING SEVEN DAYS OUT. MEAN ENSEMBLE DATA HOWEVER DO SUPPORT A TROUGH COMING IN MID-WEEK WHICH WILL SUPPRESS TEMPERATURES A BIT /THOUGH STILL ABOVE AVERAGE/ AND BRING ABOUT A SLIGHT CHANCE OF PRECIPITATION /OPTED FOR NEAR CLIMO POPS/. FWIW THE DETERMINISTIC GFS IS TRENDING A LITTLE DEEPER WITH THE SYSTEM WHILE THE TIMING HAS REMAINED FAIRLY STEADY. REGARDLESS IT DOESN/T LOOK LIKE A LARGE PRECIP MAKER AT ALL. && .AVIATION... WINDS WILL BE DECREASING ACROSS THE REGION THIS AFTERNOON AND BY 03Z WILL BE PRIMARILY TERRAIN DRIVEN. NON IMPACTFUL WINDS EXPECTED THURSDAY ALL AREAS. FEW TO SCT CLOUDS NEAR 10KFT AND LOCALIZED MVFR CEILINGS IN THE SIERRA MOUNTAINS AND FOOTHILLS DURING THE AFTERNOON HOURS. && .AIR QUALITY ISSUES... NONE. && .CERTAINTY... THE LEVEL OF CERTAINTY FOR DAYS 1 AND 2 IS HIGH. THE LEVEL OF CERTAINTY FOR DAYS 3 THROUGH 7 IS HIGH. THIS INFORMATION IS PROVIDED AS PART OF A TRIAL PROJECT CONDUCTED BY THE NATIONAL WEATHER SERVICE SAN JOAQUIN VALLEY - HANFORD. CERTAINTY LEVELS INCLUDE LOW...MEDIUM...AND HIGH. PLEASE VISIT WWW.WEATHER.GOV/HNX/CERTAINTY.PHP /ALL LOWER CASE/ FOR ADDITIONAL INFORMATION AND/OR TO PROVIDE FEEDBACK. && .CLIMATE... RECORDS SITE DATE HI_MAX:YEAR LO_MAX:YEAR HI_MIN:YEAR LO_MIN:YEAR KFAT 03-12 84:1910 50:1952 55:2005 28:1950 KFAT 03-13 84:2007 53:1981 59:1932 31:1950 KFAT 03-14 83:2007 48:1975 55:1995 29:1944 KBFL 03-12 88:1910 51:2006 56:1979 25:1907 KBFL 03-13 88:2007 53:1969 59:1979 21:1907 KBFL 03-14 88:1916 53:1944 62:1900 28:1907 && .HNX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ PUBLIC...INIGUEZ AVN/FW...INIGUEZ PREV DISCUSSION...INIGUEZ SYNOPSIS...INIGUEZ WEATHER.GOV/HANFORD
AREA FORECAST DISCUSSION
NWS TAUNTON MA
657 PM EDT WED MAR 12 2014 .SYNOPSIS... AN INTENSIFYING LOW PRESSURE WILL CROSS SOUTHERN NEW ENGLAND LATER THIS EVENING AND OVERNIGHT. RAIN WILL TRANSITION TO SNOW AS THIS LOW PRESSURE MOVES BY. TEMPERATURES PLUMMET TONIGHT...ALLOWING FOR A FLASH FREEZE. BITTERLY COLD AIR AND STRONG WINDS EXPECTED THURSDAY WITH LINGERING SNOW SHOWERS TAPER OFF DURING THE AFTERNOON. MILDER WEATHER RETURNS FRI AND SAT...BEFORE COLDER AIR RETURNS SUNDAY INTO EARLY NEXT WEEK. && .NEAR TERM /UNTIL 6 AM THURSDAY MORNING/... 7 PM UPDATE...RAIN HAS BECOME WIDESPREAD ACROSS SOUTHERN NEW ENGLAND THIS EVENING. TWO LOCATIONS TO NOTE...ONE IS A BAND OF HEAVIER RAIN STRETCHED FROM MANCHESTER NEW HAMPSHIRE SOUTHWESTWARD TO HARTFORD CONNECTICUT. SEEING RAINFALL RATES OF A TENTH OF AN INCH PER HOUR WITHIN THIS BAND OF HEAVY RAIN. THE OTHER AREA OF NOTE IS A CLUSTER FOR STRONGER ECHOES EAST OF CAPE COD. AS THIS AREA MOVED OVER NANTUCKET...LIGHTNING AND THUNDER OCCURRED AND A QUICK BURST OF HEAVY RAINFALL. EXPECT THE STRONGER ECHOES EAST OF CAPE COD AND SOUTH OF NANTUCKET TO REMAIN OFFSHORE BUT FOLKS ON NANTUCKET MAY HEAR A FEW RUMBLES OF THUNDER AS THEY PASS THE ISLAND. CAN SEE THE FRONTS PROGRESSION IN THE TEMPERATURES WITH 30S NORTH AND WEST OF A BEVERLY TO WORCESTER TO HARTFORD LINE AND UPPER 40S TO EVEN MID 50S STILL SOUTH AND EAST OF THAT LINE. MADE SOME MINOR MODIFICATIONS TO THE POPS THROUGH EARLY TOMORROW MORNING BASED ON THE LATEST TRENDS AND THE RAP POPS. OTHERWISE...THE FORECAST REMAINS ON TRACK. PREVIOUS DISCUSSION... FOR TONIGHT...EXPECTING RAINFALL TO TRANSITION TO SNOW...WITH A PERIOD OF FREEZING RAIN AND SLEET IN THE MIDDLE. WILL CONTINUE THE WINTER WEATHER ADVISORIES WHERE ALREADY ISSUED. THE MOST SIGNIFICANT CONCERN WILL BE TEMPERATURES FALLING WELL BELOW OVERNIGHT. THIS WILL LEAD TO A FREEZING OF UNTREATED SURFACES. HIGH TEMPERATURE FOR THE DAY THURSDAY SHOULD BE NEAR OR SHORTLY AFTER MIDNIGHT. SNOW ACCUMULATIONS STILL EXPECTED TO REMAIN BELOW WARNING LEVEL. && .SHORT TERM /6 AM THURSDAY MORNING THROUGH 6 PM THURSDAY/... THURSDAY... BITTERLY COLD WITH NORTHWEST WIND GUSTS OF 40 TO 50 MPH EXPECTED TO BE THE CHARACTER OF THE DAY. DESPITE A SURFACE LOW PRESSURE BEING TO OUR EAST...OUR REGION WILL STILL HAVE TO CONTEND WITH A MID LEVEL TROUGH AND SHORTWAVE. STILL THINKING THERE WILL BE SCATTERED TO NUMEROUS SNOW SHOWERS DURING THE MORNING...INCLUDING THE THURSDAY MORNING COMMUTE...MAINLY ACROSS RI AND EASTERN MA. SNOW SHOWERS TAPER OFF FROM WEST TO EAST THROUGH THE DAY. STILL EVALUATING THE NEED FOR WIND ADVISORIES. IT STILL APPEARS RATHER MARGINAL...SO DECIDED TO HOLD OFF AND LET THE NEXT SHIFT TAKE A CLOSER LOOK. STRONG COLD AIR ADVECTION WILL RESULT IN RATHER DEEP MIXING...PARTICULARLY ACROSS THE COASTAL WATERS. TEMPERATURES WILL REMAIN IN THE UPPER TEENS AND LOWER 20S ALL DAY...WHICH IS VERY IMPRESSIVE COLD FOR THIS TIME OF YEAR. WIND CHILL VALUES WILL BE BELOW ZERO. DRY AND COLD CONDITIONS EXPECTED THURSDAY NIGHT. WITH AMBIENT MIN TEMPERATURES IN THE SINGLE DIGITS AND LOW TEENS...COMBINED WITH GUSTY NORTHWEST WINDS...WIND CHILL VALUES MAY APPROACH WIND CHILL ADVISORY LEVELS. STILL TIME TO EVALUATE THAT RISK. && .LONG TERM /THURSDAY NIGHT THROUGH WEDNESDAY/... 12/12Z MODELS ARE IN GOOD AGREEMENT THROUGH THE LONG TERM. THERE ARE SOME DISCREPANCIES OUT TOWARDS THE END OF THE PERIOD BUT OVERALL THE SYNOPTIC PATTERN BOTH ALOFT AND AT THE SURFACE IS IN GOOD AGREEMENT. THERE ARE BASICALLY TWO POTENTIAL PERIODS OF PRECIPITATION IN THE LONG TERM. ONE LATE FRIDAY NIGHT INTO SATURDAY MORNING AND THE OTHER IS TUESDAY NIGHT INTO WEDNESDAY NEXT WEEK. BOTH ASSOCIATED WITH LOW PRESSURE MOVING THROUGH QUEBEC PULLING A COLD FRONT THROUGH SOUTHERN NEW ENGLAND. ASIDE FROM THESE TWO PERIODS OF PRECIPITATION...LOOKING AT DRY WEATHER WITH BELOW NORMAL TEMPERATURES. FRIDAY...LOW PRESSURE MOVES THROUGH THE GREAT LAKES INTO SOUTHERN QUEBEC. WEATHER SHOULD BE QUIET FOR MUCH OF THE DAY THOUGH EXPECT INCREASING CLOUDS FRIDAY NIGHT AHEAD OF A COLD FRONT. SATURDAY AND SUNDAY...COULD SEE A PERIOD OF MIXED PRECIPITATION AHEAD OF THE COLD FRONT BEGINNING EARLY SATURDAY MORNING...MAINLY ACROSS THE NORTHWEST INTERIOR PORTION OF THE AREA. THIS WILL BE SHORT LIVED AND COME TO AN END AS THE FRONT SWEEPS ACROSS SOUTHERN NEW ENGLAND BY MIDDAY SATURDAY. HIGH TEMPERATURES WILL ACTUALLY BE SLIGHTLY ABOVE NORMAL...REACHING INTO THE UPPER 40S TO AROUND 50. DESPITE THE PRECIPITATION...SATURDAY WILL BE THE PICK OF THE WEEKEND IN TERMS OF TEMPERATURES AS COLDER AIR MOVES IN SATURDAY NIGHT. HIGHS SUNDAY ARE EXPECTED TO BE IN THE 30S TO MID 40S AS HIGH PRESSURE BUILDS INTO SOUTHERN NEW ENGLAND. MONDAY...TEMPERATURES JUST BELOW NORMAL WILL CONTINUE AS HIGH PRESSURE CRESTS OVER THE REGION. TUESDAY AND WEDNESDAY...ANOTHER LOW PRESSURE CENTER WILL MOVE THROUGH THE GREAT LAKES INTO SOUTHERN QUEBEC BRINGING ANOTHER CHANCE OF PRECIPITATION /CURRENTLY LOOKING LIKE SNOW TUESDAY NIGHT TRANSITIONING TO RAIN WEDNESDAY/ TO THE REGION. PRECIPITATION WILL COME TO AN END LATE WEDNESDAY AS THE COLD FRONT MOVES THROUGH SOUTHERN NEW ENGLAND. TEMPERATURES REMAIN BELOW NORMAL FOR MID MARCH. && .AVIATION /00Z THURSDAY THROUGH MONDAY/... LOW...LESS THAN 30 PERCENT. MODERATE...30 TO 60 PERCENT. HIGH...GREATER THAN 60 PERCENT. SHORT TERM...THROUGH THURSDAY NIGHT. HIGH CONFIDENCE IN TRENDS...LOWER CONFIDENCE IN EXACT TIMING. TONIGHT...MAINLY IFR WITH SOME MVFR CONDITIONS. RAIN TRANSITIONS TO SNOW FROM NORTHWEST TO SOUTHEAST AS THE NIGHT WEARS ON. A BRIEF PERIOD OF SLEET/FREEZING RAIN IS POSSIBLE DURING THE TRANSITION ESPECIALLY NORTH OF THE MA TURNPIKE. NORTHERLY WINDS WILL GUST BETWEEN 20 AND 30 KNOTS BEHIND THE STORM BY LATE EVENING INTO THE OVERNIGHT HOURS. SOME LLWS POSSIBLE AS WINDS SHIFT TO THE NW RAPIDLY. THURSDAY...MVFR TO IFR CONDITIONS IN SNOW SHOWERS IN THE MORNING SHOULD IMPROVE SOME DURING THE AFTERNOON FROM WEST TO EAST. EXPECTING CONDITIONS TO IMPROVE TO MVFR...IF NOT VFR...BY MID TO LATE AFTERNOON. NORTHWEST WIND GUSTS OF 30 TO 45 KNOTS EXPECTED. THURSDAY NIGHT...HIGH CONFIDENCE VFR. PRELIMINARY SNOWFALL FORECAST... BOS...1 TO 2 INCHES TONIGHT/THU AM PVD...1/2 TO 2 INCHES TONIGHT/THU AM BDL...1/2 TO 2 INCHES TONIGHT/THU AM ORH...1-3 INCHES LATE TONIGHT/THU AM MHT...2-5 INCHES LATE TONIGHT/THU AM KBOS TERMINAL...HIGH CONFIDENCE IN TRENDS...MODERATE CONFIDENCE IN TIMING. KBDL TERMINAL...HIGH CONFIDENCE IN TRENDS...MODERATE CONFIDENCE IN TIMING. OUTLOOK...FRIDAY THROUGH MONDAY. FRIDAY...HIGH CONFIDENCE. VFR. FRIDAY NIGHT INTO SATURDAY MORNING...MODERATE CONFIDENCE. CONDITIONS DETERIORATE TO MVFR/IFR IN A WINTRY MIX OF PRECIP ACROSS THE NW INTERIOR. SATURDAY AFTERNOON THROUGH MONDAY...HIGH CONFIDENCE. VFR. && .MARINE... FORECASTER CONFIDENCE LEVELS... LOW...LESS THAN 30 PERCENT. MODERATE...30 TO 60 PERCENT. HIGH...GREATER THAN 60 PERCENT. SHORT TERM /TONIGHT THROUGH THURSDAY/...HIGH CONFIDENCE. MIXED WIND ACROSS THE WATERS THIS AFTERNOON AND EVENING WITH A BOUNDARY EXTENDING EAST FROM NEAR MARSHFIELD MA ACROSS THE SOUTHERN EXTENT OF STELLWAGEN BANK. EAST TO NORTH WINDS NORTH OF THIS BOUNDARY...WITH STRONG SOUTH WINDS SOUTH OF THIS BOUNDARY. GALE FORCE WIND GUSTS ARE EXPECTED AS A DEVELOPING LOW PRESSURE MOVES EAST ALONG THIS BOUNDARY OVERNIGHT. LOWER VSBYS IN RAIN AND SNOW EXPECTED. MODERATE FREEZING SPRAY WILL DEVELOP DURING THURSDAY AFTERNOON INTO THURSDAY NIGHT AS AN USUALLY COLD AIR MASS FOR MID MARCH ADVANCES OVER THE WATERS. LATER SHIFTS WILL LIKELY NEED TO ISSUE A FREEZING SPRAY ADVISORY. IN ADDITION...SEAS ACROSS THE EASTERN ATLANTIC WATERS WILL BUILD TO BETWEEN 7 AND 13 FEET FOR THURSDAY. WINDS AND SEAS DIMINISH THURSDAY NIGHT. OUTLOOK...FRIDAY THROUGH MONDAY... FRIDAY THROUGH SATURDAY...HIGH CONFIDENCE. SMALL CRAFT ADVISORIES LIKELY NEEDED WITH SOUTHWESTERLY WINDS GUSTING TO 30 KTS AHEAD OF A COLD FRONT MOVING OVER THE WATERS. SEAS INCREASE TO 5 TO 7 FEET ON THE OUTER WATERS. SATURDAY NIGHT...HIGH CONFIDENCE. WINDS SHIFT TO THE NORTHWEST AND WINDS AND SEAS GRADUALLY DIMINISH BEHIND THE COLD FRONT. SUNDAY...MODERATE CONFIDENCE. WINDS AND SEAS SHOULD REMAIN BELOW SMALL CRAFT CRITERIA FOR MOST OF THE PERIOD AS HIGH PRESSURE BUILDS OVER THE WATERS. MONDAY...MODERATE CONFIDENCE. WINDS AND SEAS INCREASE TO JUST OVER SMALL CRAFT CRITERIA ON THE OUTER WATERS. && .CLIMATE... NEAR RECORD COLD POSSIBLE THU NIGHT INTO EARLY FRIDAY. HERE ARE RECORD LOW TEMPERATURES FOR FRIDAY MARCH 14TH... BOSTON.......12/1896...FORECAST LOW...14 PROVIDENCE...12/1948...FORECAST LOW...13 BRADLEY ARPT..7/1948...FORECAST LOW...9 WORCESTER.....4/1948...FORECAST LOW...8 && .BOX WATCHES/WARNINGS/ADVISORIES... CT...WINTER WEATHER ADVISORY FROM 10 PM THIS EVENING TO NOON EDT THURSDAY FOR CTZ002>004. MA...WINTER WEATHER ADVISORY UNTIL NOON EDT THURSDAY FOR MAZ002-003. WINTER WEATHER ADVISORY FROM 10 PM THIS EVENING TO NOON EDT THURSDAY FOR MAZ004>019-026. NH...WINTER WEATHER ADVISORY UNTIL NOON EDT THURSDAY FOR NHZ011-012- 015. RI...WINTER WEATHER ADVISORY FROM 10 PM THIS EVENING TO NOON EDT THURSDAY FOR RIZ001>005. MARINE...GALE WARNING FROM 8 AM TO 8 PM EDT THURSDAY FOR ANZ232>235-237- 254>256. GALE WARNING FROM 5 AM TO 8 PM EDT THURSDAY FOR ANZ230-236. GALE WARNING FROM 2 AM TO 8 PM EDT THURSDAY FOR ANZ231-250-251. && $$ SYNOPSIS...BELK/RLG NEAR TERM...BELK/RLG SHORT TERM...BELK LONG TERM...RLG AVIATION...BELK/RLG MARINE...BELK/RLG CLIMATE...
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
256 PM CDT WED MAR 12 2014 .DISCUSSION... 700 AM CDT HAVE LET THE FEW NORTHERN PARTS OF THE ADVISORY EXPIRE AT 7 AM WITH NO OTHER CHANGES TO CURRENT HEADLINES. SOME MINOR ADJUSTMENTS MADE TO THE MORNING FORECAST. THE PRIMARY UPPER WAVE IS VERY WELL-DEFINED ON SATELLITE AND RADAR THIS MORNING AND ITS CENTER CONTINUES TO MOVE EAST INTO INDIANA. THE SYSTEM DEFORMATION CONTINUES TO INTENSIFY WITH THE COLD CONVEYOR BELT STRENGTHENING INTO THE SYSTEM WITH COPIOUS AMOUNTS OF MOISTURE CONTINUING TO BE WRAPPED INTO THE BACKSIDE. ALSO HIGHLIGHTING THIS IS A BLOSSOMING OF REFLECTIVITY ACROSS EAST CENTRAL ILLINOIS AS OF 700 AM WITH LIKELY SOME 1 IN/HR RATES TEMPORARILY SEEN WITH THIS AS IT MOVES EAST THROUGH 9 AM. FROM MONITORING LOCAL MEDIA AND BASED ON A PLETHORA OF REPORTS...BLOWING SNOW IS OCCURRING IN MANY PLACES DUE TO THE WINDS. SO CONCERNS ABOUT THE SNOW COMPOSITION POTENTIALLY BEING TOO WET SEEM TO BE PUT TO REST IN MANY PLACES THANKS TO THE HIGHER END DEGREE OF GUSTS. IN ADDITION...THE NORTHERN STREAM SHORT WAVE CONTINUES TO DIG SOUTH AND HAVE INFLUENCE ON THE MAIN SYSTEM. THIS WAVE IN ITSELF IS PRODUCING LIGHT PRECIP IN THE FORM OF MAINLY FLURRIES BUT ALSO SOME FREEZING DRIZZLE. THIS IS ASSOCIATED WITH FOCUSED ASCENT WITHIN/ABOVE LOW-LEVEL CONVERGENCE. THESE ELEMENTS ON THE RAP DROP SOUTHWARD INTO NORTHERN ILLINOIS THIS MORNING AND HIGH RES GUIDANCE SUCH AS THE LOCAL ARW AND THE HOPWRF ENSEMBLE BRING LIGHT PRECIP SOUTH AS WELL. HAVE INCREASED THE COVERAGE OF FLURRIES IN THE FORECAST AND ADDED FREEZING DRIZZLE MENTION AS FORECAST PROFILES REMAIN BORDERLINE FOR EITHER...WHICH LINES UP WITH OBSERVATIONAL TRENDS. HAVE KEPT THE FREEZING DRIZZLE MENTION WEST OF CHICAGO FOR THE TIME BEING BASED ON EXTRAPOLATION OF ONGOING REPORTS. MTF //PREV DISCUSSION... 350 AM CDT REST OF TODAY... THE PRIMARY CHANGES IN THE FORECAST WERE A QUICKER DIMINISHING OF ANY LIGHT SNOW CHANCES AS WELL AS TO BUMP UP TEMPERATURES NAMELY THIS MORNING. DEEP DRY AIR AND SUPPRESSION LOOK TO MOVE QUICKLY INTO THE AREA BY LATE MORNING BEHIND THIS SYSTEM. CONTINUING LOW- LEVEL CYCLOGENESIS OFF TO THE EAST WILL DRIVE COLD AIR ADVECTION INTO THE REGION...AND PROFILES WILL BE SUPPORTIVE OF KEEPING STRATOCU AND MAYBE SOME FLURRIES INTO EARLY TO MID AFTERNOON. TEMPERATURES ARE FAIRLY HOMOGENEOUS UP TO CENTRAL/SOUTHERN WI EARLY THIS MORNING...SO LOW-LEVEL THERMAL ADVECTION LOOKS TO BE NEUTRAL THROUGH DAYBREAK AND THEN SLIGHT COLD AIR ADVECTION THIS MORNING. TEMPERATURES SHOULD LEVEL OUT THIS AFTERNOON AS AT LEAST SOME MARCH SUNSHINE OFFSETS ANY COLD AIR ADVECTION. WITH NOT AS COLD OF AIR QUICKLY COMING INTO THE AREA...THE POSSIBILITY OF LAKE EFFECT SNOW SHOWERS INTO NORTHWEST INDIANA LOOKS QUITE SMALL...BUT POSSIBLY SOME CLOUDS GENERATING INTO LAKE AND PORTER COUNTIES THIS AFTERNOON. TONIGHT... HIGH PRESSURE WILL MOVE OVER THE REGION TONIGHT AND SET THE STAGE FOR A COLD NIGHT BY MID-MARCH STANDARDS. HIGH CLOUDS DO LOOK TO SPILL INTO THE WESTERN FORECAST AREA AS THE NIGHT PROGRESSES AS A SHEARED WEAK SHORTWAVE DROPS SOUTHWARD ON THE BACKSIDE OF THE DEVELOPING LONGWAVE TROUGH. BUT IT LOOKS TO BE A LITTLE TOO LATE TO STOP TEMPERATURES FROM DROPPING NICELY OVER FRESH SNOW COVER THIS EVE INTO EARLY OVERNIGHT. FORECAST TEMPERATURES WITH MODEST CONFIDENCE ARE SINGLE DIGITS IN OUTLYING AREAS TO 10 TO 15 IN THE CHICAGO METRO. THAT LINES UP WITH THE 850MB TEMPERATURES OF -12C TO -15C ACROSS THE FORECAST AREA BY TONIGHT...WHICH ARE WELL BELOW CLIMO. IF CLOUDS WERE TO MOVE IN QUICKER IT WOULD RESULT IN MINS POTENTIALLY QUITE A BIT WARMER. THURSDAY AND BEYOND... WHILE THE UPPER FLOW PATTERN BECOMES NORTHWEST AND REMAINS DECENTLY ACTIVE THROUGH THE REST OF THE FORECAST PERIOD...WE REMAIN ON THE ANTICYCLONIC SIDE. THUS WE LOOK TO FREQUENTLY MISS THE BEST FORCING AND DEEPER SATURATION OF EACH QUICK-MOVING SYSTEM. IT DOES MAKE FOR A CHALLENGE WITH TEMPERATURES...ESPECIALLY WEIGHING RECENT SNOW COVER AND OCCASIONALLY PASSING CLOUD COVER. DO MAINTAIN A SMALL CHANCE FOR LIGHT SNOW THURSDAY MORNING IN NORTHERN AREAS AS WARM AIR ADVECTION ALOFT MOVES IN BEHIND THE TROUGH. SATURATION LOOKS TO BE A PROBLEM...BUT THE ISENTROPIC ASCENT IS PRETTY STRONG AND SATURATION ON BOTH THE NAM AND GFS IS DEPICTED TO BE LOW ENOUGH FOR SOME LIGHT SNOW TO REACH THE GROUND...IF IT CAN MATERIALIZE. FRIDAY LOOKS MILD WITH TEMPERATURES POTENTIALLY PUSHING 50 DEGREES AS WEST SOUTHWEST LOW-LEVEL FLOW BRING A WARM SECTOR OF ONE OF THE QUICK-MOVING SYSTEMS INTO OUR AREA. HAVE GONE WITH AN GFS/EC BLEND FOR THE WEEKEND INTO EARLY NEXT WEEK. THE GFS IS CONSIDERABLY COLDER FOR SUNDAY AND SUNDAY NIGHT WITH A STRONG CANADIAN HIGH PASSING OVER THE AREA...WHILE THE EC FAVORS THIS FEATURE TO BE MUCH FURTHER NORTH AND WEAKER. MTF && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 20Z... * GUSTY NORTH WINDS WITH MAX GUSTS ARND 25 KT BECOMING NNW AFT 00Z. * SOUTH TO SOUTH-SOUTHEAST WINDS GUSTING TO 15-20 KT TOMORROW AFTERNOON. JEE //DISCUSSION...UPDATED 18Z... THE LOW IS NOW OVER SOUTHWESTERN PA WITH HIGH PRESSURE OVER SOUTHERN ONTARIO. THE BAND OF SNOW THAT IMPACTED RFD HAS SHIFTED SOUTH AND NOT EXPECTING ANY FURTHER PRECIP AT THE TERMINALS. DID NOT MAKE MANY CHANGES TO THE TAFS AS THE PREVIOUS TAFS SEEM ON TRACK. STILL NOT 100 PERCENT CERTAIN ON WHEN THE MVFR CIGS WILL LIFT AS THEY EXTEND UP THROUGH SOUTHERN WI AND CONTINUE TO FILTER INTO NORTHERN IL AND IN. GUIDANCE CONTINUES TO SUGGEST THEY DISSIPATE IN THE EARLY AFTN SO KEPT THE 19-21Z TIMING IN THE TAFS. AS THE LOW CONTINUES OFF TO THE EAST...WINDS WILL BECOME NNW AND BEGIN TO DIMINISH. A HIGH PRESSURE RIDGE MOVES OVER THE REGION TONIGHT WITH LIGHT AND VARIABLE WINDS EXPECTED. WINDS WILL BE SSW BEHIND THE RIDGE TOMORROW MORNING...AND GUST TO 15-20 KT IN THE AFTERNOON. JEE //ORD AND MDW CONFIDENCE...UPDATED 20Z... * HIGH CONFIDENCE IN ALL FORECAST ELEMENTS. JEE //OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z... * THURSDAY NIGHT...DRY/VFR. * FRIDAY...DRY/VFR. GUSTY WESTERLY WINDS. * SATURDAY THROUGH SUNDAY...DRY/VFR. * TUESDAY...CHANCE OF RAIN/SNOW. MVFR POSSIBLE. && .MARINE... 210 PM CDT LOW PRESSURE OVER THE CENTRAL PLAINS WILL CONTINUE TO DEEPEN AS IT TRACKS EAST ACROSS SOUTHERN ILLINOIS TONIGHT AND INTO THE OHIO VALLEY WEDNESDAY. AS THE LOW TRACKS SOUTH AND THEN SOUTHEAST OF THE LAKE...HIGH PRESSURE WILL ALSO BUILD ACROSS THE UPPER GREAT LAKES REGION...SETTING UP STRONG NORTH WINDS. THE COMBINATION OF A STRONG GRADIENT AND STRONG COLD ADVECTION WILL LEAD TO WINDS QUICKLY INCREASING TO GALES BY LATE THIS EVENING. THE LATEST GUIDANCE HAS BEEN RELATIVELY CONSISTENT IN INDICATING THE POTENTIAL FOR HIGH END GALES BY LATE WEDNESDAY MORNING AND EARLY AFTERNOON...WITH THE STRONGEST GALES OVER THE SOUTHERN PORTIONS OF THE LAKE...INCLUDING THE NEARSHORE WATERS. BY WEDNESDAY EVENING...THE HIGH PRESSURE WILL BEGIN TO SPREAD ACROSS LAKE MICHIGAN ALLOWING WINDS TO SUBSIDE BELOW GALE FORCE. BY THURSDAY NIGHT...THE HIGH WILL PUSH TO THE SOUTHEAST OF THE LAKE AS A CLIPPER DROPS OUT OF NORTHERN ALBERTA AND SWINGS JUST NORTH OF THE UPPER GREAT LAKES ON FRIDAY. WITH THE SFC HIGH SAGGING OFF THE SERN COAST...A PERIOD OF SWLY WINDS WILL DEVELOP AHEAD OF AN APPROACHING COLD FRONT TRAILING FROM THE CLIPPER. ANTICIPATE A PERIOD OF BRISK SLY TO SWLY WINDS FOR THURSDAY NIGHT THROUGH FRIDAY...BUT MORE GALES ARE NOT EXPECTED AT THIS TIME. AS THE CLIPPER TURNS NEWD INTO QUEBEC...IT WILL DRAG A WEAK COLD FRONT DOWN THE LAKE WITH ANOTHER ARCTIC HIGH BUILDING IN BEHIND THE FRONT. 25-30KT NORTH WINDS WILL SET UP FOLLOWING THE FROPA FOR SATURDAY NIGHT AND SUNDAY...BUT AS THE HIGH SPREADS ACROSS THE GREAT LAKES SUNDAY NIGHT...WINDS SHOULD BECOME MORE LIGHT AND VARIABLE. KREIN && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...GALE WARNING...LMZ080-LMZ669-LMZ671-LMZ673-LMZ675-LMZ740-LMZ741- LMZ742-LMZ743-LMZ744-LMZ745-LMZ777-LMZ779-LMZ870-LMZ872- LMZ874-LMZ876-LMZ878 UNTIL 10 PM WEDNESDAY. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1248 PM CDT WED MAR 12 2014 .DISCUSSION... 700 AM CDT HAVE LET THE FEW NORTHERN PARTS OF THE ADVISORY EXPIRE AT 7 AM WITH NO OTHER CHANGES TO CURRENT HEADLINES. SOME MINOR ADJUSTMENTS MADE TO THE MORNING FORECAST. THE PRIMARY UPPER WAVE IS VERY WELL-DEFINED ON SATELLITE AND RADAR THIS MORNING AND ITS CENTER CONTINUES TO MOVE EAST INTO INDIANA. THE SYSTEM DEFORMATION CONTINUES TO INTENSIFY WITH THE COLD CONVEYOR BELT STRENGTHENING INTO THE SYSTEM WITH COPIOUS AMOUNTS OF MOISTURE CONTINUING TO BE WRAPPED INTO THE BACKSIDE. ALSO HIGHLIGHTING THIS IS A BLOSSOMING OF REFLECTIVITY ACROSS EAST CENTRAL ILLINOIS AS OF 700 AM WITH LIKELY SOME 1 IN/HR RATES TEMPORARILY SEEN WITH THIS AS IT MOVES EAST THROUGH 9 AM. FROM MONITORING LOCAL MEDIA AND BASED ON A PLETHORA OF REPORTS...BLOWING SNOW IS OCCURRING IN MANY PLACES DUE TO THE WINDS. SO CONCERNS ABOUT THE SNOW COMPOSITION POTENTIALLY BEING TOO WET SEEM TO BE PUT TO REST IN MANY PLACES THANKS TO THE HIGHER END DEGREE OF GUSTS. IN ADDITION...THE NORTHERN STREAM SHORT WAVE CONTINUES TO DIG SOUTH AND HAVE INFLUENCE ON THE MAIN SYSTEM. THIS WAVE IN ITSELF IS PRODUCING LIGHT PRECIP IN THE FORM OF MAINLY FLURRIES BUT ALSO SOME FREEZING DRIZZLE. THIS IS ASSOCIATED WITH FOCUSED ASCENT WITHIN/ABOVE LOW-LEVEL CONVERGENCE. THESE ELEMENTS ON THE RAP DROP SOUTHWARD INTO NORTHERN ILLINOIS THIS MORNING AND HIGH RES GUIDANCE SUCH AS THE LOCAL ARW AND THE HOPWRF ENSEMBLE BRING LIGHT PRECIP SOUTH AS WELL. HAVE INCREASED THE COVERAGE OF FLURRIES IN THE FORECAST AND ADDED FREEZING DRIZZLE MENTION AS FORECAST PROFILES REMAIN BORDERLINE FOR EITHER...WHICH LINES UP WITH OBSERVATIONAL TRENDS. HAVE KEPT THE FREEZING DRIZZLE MENTION WEST OF CHICAGO FOR THE TIME BEING BASED ON EXTRAPOLATION OF ONGOING REPORTS. MTF //PREV DISCUSSION... 350 AM CDT REST OF TODAY... THE PRIMARY CHANGES IN THE FORECAST WERE A QUICKER DIMINISHING OF ANY LIGHT SNOW CHANCES AS WELL AS TO BUMP UP TEMPERATURES NAMELY THIS MORNING. DEEP DRY AIR AND SUPPRESSION LOOK TO MOVE QUICKLY INTO THE AREA BY LATE MORNING BEHIND THIS SYSTEM. CONTINUING LOW- LEVEL CYCLOGENESIS OFF TO THE EAST WILL DRIVE COLD AIR ADVECTION INTO THE REGION...AND PROFILES WILL BE SUPPORTIVE OF KEEPING STRATOCU AND MAYBE SOME FLURRIES INTO EARLY TO MID AFTERNOON. TEMPERATURES ARE FAIRLY HOMOGENEOUS UP TO CENTRAL/SOUTHERN WI EARLY THIS MORNING...SO LOW-LEVEL THERMAL ADVECTION LOOKS TO BE NEUTRAL THROUGH DAYBREAK AND THEN SLIGHT COLD AIR ADVECTION THIS MORNING. TEMPERATURES SHOULD LEVEL OUT THIS AFTERNOON AS AT LEAST SOME MARCH SUNSHINE OFFSETS ANY COLD AIR ADVECTION. WITH NOT AS COLD OF AIR QUICKLY COMING INTO THE AREA...THE POSSIBILITY OF LAKE EFFECT SNOW SHOWERS INTO NORTHWEST INDIANA LOOKS QUITE SMALL...BUT POSSIBLY SOME CLOUDS GENERATING INTO LAKE AND PORTER COUNTIES THIS AFTERNOON. TONIGHT... HIGH PRESSURE WILL MOVE OVER THE REGION TONIGHT AND SET THE STAGE FOR A COLD NIGHT BY MID-MARCH STANDARDS. HIGH CLOUDS DO LOOK TO SPILL INTO THE WESTERN FORECAST AREA AS THE NIGHT PROGRESSES AS A SHEARED WEAK SHORTWAVE DROPS SOUTHWARD ON THE BACKSIDE OF THE DEVELOPING LONGWAVE TROUGH. BUT IT LOOKS TO BE A LITTLE TOO LATE TO STOP TEMPERATURES FROM DROPPING NICELY OVER FRESH SNOW COVER THIS EVE INTO EARLY OVERNIGHT. FORECAST TEMPERATURES WITH MODEST CONFIDENCE ARE SINGLE DIGITS IN OUTLYING AREAS TO 10 TO 15 IN THE CHICAGO METRO. THAT LINES UP WITH THE 850MB TEMPERATURES OF -12C TO -15C ACROSS THE FORECAST AREA BY TONIGHT...WHICH ARE WELL BELOW CLIMO. IF CLOUDS WERE TO MOVE IN QUICKER IT WOULD RESULT IN MINS POTENTIALLY QUITE A BIT WARMER. THURSDAY AND BEYOND... WHILE THE UPPER FLOW PATTERN BECOMES NORTHWEST AND REMAINS DECENTLY ACTIVE THROUGH THE REST OF THE FORECAST PERIOD...WE REMAIN ON THE ANTICYCLONIC SIDE. THUS WE LOOK TO FREQUENTLY MISS THE BEST FORCING AND DEEPER SATURATION OF EACH QUICK-MOVING SYSTEM. IT DOES MAKE FOR A CHALLENGE WITH TEMPERATURES...ESPECIALLY WEIGHING RECENT SNOW COVER AND OCCASIONALLY PASSING CLOUD COVER. DO MAINTAIN A SMALL CHANCE FOR LIGHT SNOW THURSDAY MORNING IN NORTHERN AREAS AS WARM AIR ADVECTION ALOFT MOVES IN BEHIND THE TROUGH. SATURATION LOOKS TO BE A PROBLEM...BUT THE ISENTROPIC ASCENT IS PRETTY STRONG AND SATURATION ON BOTH THE NAM AND GFS IS DEPICTED TO BE LOW ENOUGH FOR SOME LIGHT SNOW TO REACH THE GROUND...IF IT CAN MATERIALIZE. FRIDAY LOOKS MILD WITH TEMPERATURES POTENTIALLY PUSHING 50 DEGREES AS WEST SOUTHWEST LOW-LEVEL FLOW BRING A WARM SECTOR OF ONE OF THE QUICK-MOVING SYSTEMS INTO OUR AREA. HAVE GONE WITH AN GFS/EC BLEND FOR THE WEEKEND INTO EARLY NEXT WEEK. THE GFS IS CONSIDERABLY COLDER FOR SUNDAY AND SUNDAY NIGHT WITH A STRONG CANADIAN HIGH PASSING OVER THE AREA...WHILE THE EC FAVORS THIS FEATURE TO BE MUCH FURTHER NORTH AND WEAKER. MTF && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 18Z... * MVFR CIGS INTO EARLY THIS AFTERNOON. * GUSTY NORTH WINDS WITH MAX GUSTS ARND 30 KT DIMINISHING AND BECOMING NNW EARLY THIS AFTN. GUSTS ARND 25 KT EXPECTED THIS AFTN. * SOUTH TO SOUTH-SOUTHEAST WINDS GUSTING TO 15-20 KT TOMORROW AFTERNOON. JEE //DISCUSSION...UPDATED 18Z... THE LOW IS NOW OVER SOUTHWESTERN PA WITH HIGH PRESSURE OVER SOUTHERN ONTARIO. THE BAND OF SNOW THAT IMPACTED RFD HAS SHIFTED SOUTH AND NOT EXPECTING ANY FURTHER PRECIP AT THE TERMINALS. DID NOT MAKE MANY CHANGES TO THE TAFS AS THE PREVIOUS TAFS SEEM ON TRACK. STILL NOT 100 PERCENT CERTAIN ON WHEN THE MVFR CIGS WILL LIFT AS THEY EXTEND UP THROUGH SOUTHERN WI AND CONTINUE TO FILTER INTO NORTHERN IL AND IN. GUIDANCE CONTINUES TO SUGGEST THEY DISSIPATE IN THE EARLY AFTN SO KEPT THE 19-21Z TIMING IN THE TAFS. AS THE LOW CONTINUES OFF TO THE EAST...WINDS WILL BECOME NNW AND BEGIN TO DIMINISH. A HIGH PRESSURE RIDGE MOVES OVER THE REGION TONIGHT WITH LIGHT AND VARIABLE WINDS EXPECTED. WINDS WILL BE SSW BEHIND THE RIDGE TOMORROW MORNING...AND GUST TO 15-20 KT IN THE AFTERNOON. JEE //ORD AND MDW CONFIDENCE...UPDATED 18Z... * HIGH CONFIDENCE IN CIG TRENDS...MEDIUM-HIGH CONFIDENCE IN WHEN MVFR CIGS LIFT TO VFR. * HIGH CONFIDENCE IN ALL OTHER FORECAST ELEMENTS. JEE //OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z... * THURSDAY NIGHT...DRY/VFR. * FRIDAY...DRY/VFR. GUSTY WESTERLY WINDS. * SATURDAY THROUGH SUNDAY...DRY/VFR. * TUESDAY...CHANCE OF RAIN/SNOW. MVFR POSSIBLE. && .MARINE... 210 PM CDT LOW PRESSURE OVER THE CENTRAL PLAINS WILL CONTINUE TO DEEPEN AS IT TRACKS EAST ACROSS SOUTHERN ILLINOIS TONIGHT AND INTO THE OHIO VALLEY WEDNESDAY. AS THE LOW TRACKS SOUTH AND THEN SOUTHEAST OF THE LAKE...HIGH PRESSURE WILL ALSO BUILD ACROSS THE UPPER GREAT LAKES REGION...SETTING UP STRONG NORTH WINDS. THE COMBINATION OF A STRONG GRADIENT AND STRONG COLD ADVECTION WILL LEAD TO WINDS QUICKLY INCREASING TO GALES BY LATE THIS EVENING. THE LATEST GUIDANCE HAS BEEN RELATIVELY CONSISTENT IN INDICATING THE POTENTIAL FOR HIGH END GALES BY LATE WEDNESDAY MORNING AND EARLY AFTERNOON...WITH THE STRONGEST GALES OVER THE SOUTHERN PORTIONS OF THE LAKE...INCLUDING THE NEARSHORE WATERS. BY WEDNESDAY EVENING...THE HIGH PRESSURE WILL BEGIN TO SPREAD ACROSS LAKE MICHIGAN ALLOWING WINDS TO SUBSIDE BELOW GALE FORCE. BY THURSDAY NIGHT...THE HIGH WILL PUSH TO THE SOUTHEAST OF THE LAKE AS A CLIPPER DROPS OUT OF NORTHERN ALBERTA AND SWINGS JUST NORTH OF THE UPPER GREAT LAKES ON FRIDAY. WITH THE SFC HIGH SAGGING OFF THE SERN COAST...A PERIOD OF SWLY WINDS WILL DEVELOP AHEAD OF AN APPROACHING COLD FRONT TRAILING FROM THE CLIPPER. ANTICIPATE A PERIOD OF BRISK SLY TO SWLY WINDS FOR THURSDAY NIGHT THROUGH FRIDAY...BUT MORE GALES ARE NOT EXPECTED AT THIS TIME. AS THE CLIPPER TURNS NEWD INTO QUEBEC...IT WILL DRAG A WEAK COLD FRONT DOWN THE LAKE WITH ANOTHER ARCTIC HIGH BUILDING IN BEHIND THE FRONT. 25-30KT NORTH WINDS WILL SET UP FOLLOWING THE FROPA FOR SATURDAY NIGHT AND SUNDAY...BUT AS THE HIGH SPREADS ACROSS THE GREAT LAKES SUNDAY NIGHT...WINDS SHOULD BECOME MORE LIGHT AND VARIABLE. KREIN && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...GALE WARNING...LMZ080-LMZ669-LMZ671-LMZ673-LMZ675-LMZ740-LMZ741- LMZ742-LMZ743-LMZ744-LMZ745-LMZ777-LMZ779-LMZ870-LMZ872- LMZ874-LMZ876-LMZ878 UNTIL 10 PM WEDNESDAY. GALE WARNING...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-LMZ567- LMZ868 UNTIL 7 PM WEDNESDAY. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
701 PM EDT WED MAR 12 2014 .UPDATE... THE NEAR TERM SECTION HAS BEEN UPDATED BELOW. && .SYNOPSIS... ISSUED AT 321 PM EDT WED MAR 12 2014 MUCH COLDER AIR WILL RETURN INTO THE REGION TONIGHT WITH HIGH PRESSURE. THE CHILLY WEATHER WILL BE SHORT-LIVED...AS THE PASSAGE OF A WARM FRONT THURSDAY NIGHT WILL USHER IN MILDER TEMPERATURES FRIDAY. AFTER A WEAK COLD FRONT BRINGS A CHANCE FOR LIGHT RAIN FRIDAY NIGHT...COOLER WEATHER WILL RETURN INTO EARLY NEXT WEEK. && .NEAR TERM /TONIGHT/... ISSUED AT 701 PM EDT WED MAR 12 2014 DID A QUICK UPDATE TO ADD FLURRIES PAST 00Z ACROSS THE FAR WESTERN FORECAST AREA AS RADAR SHOWS SNOW SHOWERS AND FLURRIES ACROSS EASTERN ILLINOIS MOVING SOUTHEAST. KEPT MENTIONABLE POPS ACROSS THE FAR SOUTHWEST WHO WILL HAVE THE BEST CHANCE /BUT STILL LOW/ OF SEEING MEASURABLE SNOW. PREVIOUS DISCUSSION FOLLOWS... BACK EDGE OF THE LIGHT SNOW ASSOCIATED WITH THE LOW PRESSURE MOVING ACROSS THE EASTERN HALF OF THE FORECAST AREA AS OF 19Z. ANOTHER AREA OF WHAT APPEARS TO BE CONVECTIVE SNOW SHOWERS OVER NORTHERN/CENTRAL ILLINOIS ASSOCIATED WITH AN UPPER LEVEL WAVE CONTINUES TO MOVE SLOWLY SOUTHEAST. TEMPS HAVE BEEN GENERALLY STEADY-STATE IN THE LOWER/MID 30S OVER THE LAST FEW HOURS. WENT AHEAD AND DROPPED BOTH HEADLINES /WINTER WEATHER AND WIND ADVISORIES/ AS SNOW HAS LIGHTENED CONSIDERABLY AND WIND GUSTS HAVE DROPPED BELOW 40MPH. ADDITIONALLY...WITH A GENERALLY HEAVY WET SNOW IN THE LOCATIONS WHERE SOME ACCUMULATION WAS EXPERIENCED...THE BLOWING SNOW CONCERNS HAVE BEEN GREATLY DIMINISHED. INITIAL ISSUE FOCUSES ON THE AREA OF SNOW OVER ILLINOIS. MOST SHORT RANGE MODEL GUIDANCE STRUGGLING WITH THIS...BUT HRRR HINTS AT BRINGING THE AXIS OF SNOW ACROSS THE LOWER WABASH VALLEY INTO THE EVENING. ADDITIONALLY...RAP SOUNDINGS SHOWING SUBTLE INSTABILITY PRESENT FOR THE NEXT FEW HOURS. WILL PUT LOW CHANCE POPS IN THROUGH MID EVENING FROM TERRE HAUTE TO WASHINGTON AND POINTS WEST. EVEN THOUGH MAY HAVE BRIEF BURSTS OF HEAVIER SNOW SHOWERS WITHIN CONVECTION...SURFACE/GROUND TEMPS ARE ABOVE FREEZING AND EXPECT IMPACTS TO BE MINIMAL. REMAINDER OF THE FORECAST IS QUIET FOR TONIGHT AS WEAK HIGH PRESSURE BUILDS IN OVERNIGHT. EXPECT SKIES TO BECOME CLEAR TONIGHT WITH WIND GUSTS DIMINISHING DURING THE EVENING AS THE SURFACE PRESSURE GRADIENT RELAXES. TEMPS...COLD NIGHT BY MARCH STANDARDS AS CLEAR SKIES WITH A FRESH SNOWPACK OVER NORTHERN COUNTIES SHOULD ENABLE TEMPS TO TUMBLE INTO THE SINGLE DIGITS. EVEN FOR THE REMAINDER OF THE FORECAST AREA THAT IS FREE OF SNOW COVER...EXPECT TEMPS TO BOTTOM OUT IN THE TEENS. GENERALLY WENT WITH WARMER MAVMOS IN SNOW-FREE AREAS...AND MUCH CLOSER TO COLDER METMOS OVER NORTHERN COUNTIES. && .SHORT TERM /THURSDAY THROUGH SATURDAY/... ISSUED AT 321 PM EDT WED MAR 12 2014 FORECAST CHALLENGES FOCUS ON PRECIP CHANCES WITH A WEAK FRONT LATE FRIDAY...AND TEMPS THROUGHOUT THE FORECAST PERIOD. THE FRENETIC PACE TO WEATHER ACROSS THE REGION AS OF LATE WILL CONTINUE THROUGH THE PERIOD...WITH THIS BRIEF RETURN TO WINTER FOLLOWED BY YET ANOTHER REMINDER BY FRIDAY THAT SPRING IS DEFINITELY ON THE HORIZON. COLD BUT SUNNY START ON THURSDAY WITH HIGH PRESSURE RIDGE OVER THE OHIO VALLEY. THE SURFACE RIDGE WILL SHIFT EAST QUICKLY BY THURSDAY AFTERNOON WITH INCREASING LOW LEVEL WARM ADVECTION COMMENCING BY LATE DAY...FOLLOWED BY THE PASSAGE OF A DRY WARM FRONT THURSDAY NIGHT. EXPECT A PERIOD WITH INCREASED MID/HIGH LEVEL CLOUDS THURSDAY AFTERNOON AND EVENING IMMEDIATELY AHEAD OF THE WARM FRONT...WITH SKIES CLEARING OVERNIGHT. RETURN OF RIDGING ALOFT ON FRIDAY AND SOUTHWEST FLOW AHEAD OF AN APPROACHING WEAK COLD FRONT WILL SET THE STAGE FOR A MILD YET WINDY DAY. LOW LEVEL JET WILL OVERSPREAD THE REGION BY FRIDAY AFTERNOON AHEAD OF THE FRONT AND WITH MODEST MIXING LEVELS UP TO ABOUT 3KFT...SHOULD HAVE NO PROBLEM PULLING SOME STRONGER GUSTS TO 30-35MPH DOWN TO THE SURFACE. THE FRONT WILL INITIALLY BE LACKING MOISTURE BUT AS IT MOVES INTO THE OHIO VALLEY FRIDAY EVENING...IT WILL TAP INTO A SLIGHTLY BETTER FETCH OF GULF MOISTURE. COMBINED WITH AN AXIS OF LOW LEVEL CONVERGENCE ALONG THE FRONT AND A BRIEF YET SUBTLE PERIOD OF ISENTROPIC LIFT...EXPECT A FEW LIGHT RAIN SHOWERS TO DEVELOP FRIDAY EVENING...SHIFTING SOUTH OF THE FORECAST AREA PRIOR TO DAYBREAK SATURDAY. THE DEEPER MOISTURE DEPARTS AHEAD OF THE COLDER AIR...SO ANTICIPATE PRECIP TO FALL ENTIRELY AS LIGHT RAIN. WEAK HIGH PRESSURE WILL THEN REESTABLISH FOR SATURDAY WITH DRY WEATHER AND SLIGHTLY COOLER TEMPS. TEMPS...ARRIVAL OF WARM ADVECTION BY AFTERNOON SHOULD ENABLE A NICE RECOVERY THURS WITH HIGHS INTO THE 30S. MAVMOS IN PARTICULAR APPEARS TO BE A LITTLE TOO AGGRESSIVE WITH THE WARMUP...AND UNDERCUT BY A FEW DEGREES IN GENERAL. FOLLOWED THE RECENT TREND OF GOING ABOVE MOS FOR HIGHS FRIDAY AS COMBINATION OF WARM ADVECTION...SOUTHWEST FLOW AND COMPRESSIONAL HEATING AHEAD OF THE FRONT WILL ALLOW TEMPS TO APPROACH 60 ACROSS ALL BUT NORTHERN COUNTIES. MOS LOOKED REASONABLE FOR HIGHS SATURDAY GENERALLY IN THE UPPER 40S AND 50S. BOUNDARY LAYER THERMALS SUPPORTED MOS GUIDANCE FOR LOWS THROUGH THE PERIOD. && .LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/... ISSUED AT 149 PM EDT WED MAR 12 2014 HIGH VARIABILITY AND LOW CONFIDENCE DURING THIS PERIOD AS MODELS SUGGEST SEVERAL WEAKER SYSTEMS PASSING THROUGH THE AREA ALBEIT WITH LIMITED MOISTURE. GFS PUSHES SOME UPPER SUPPORT AND A WEAK TROUGH THROUGH THE AREA ON MONDAY...HOWEVER MOISTURE REMAINS LIMITED AND CONFIDENCE IS LOW AS THE ECMWF PUSHES BETTER SUPPORT THROUGH DEEP SOUTH. A WARMING TREND IS NOTED THROUGH THE PERIOD AS STRONG WARM AIR ADVECTION IS SEEN IN THE GFS ON TUE THROUGH WEDNESDAY. A THERMAL RIDGE ACTUALLY BUILD ACROSS ILLINOIS AND INDIANA WITH 850MB TEMPS RISING TOWARD 11C. THIS SHOULD PRODUCE SOME TEMPS AT OR ABOVE NORMALS. HAVE INCLUDED A CHC FOR RAIN ON WEDNESDAY AS A GFS SUGGEST A COLD FRONTAL PASSAGE...STILL VERY LOW CONFIDENCE. && .AVIATION /DISCUSSION FOR THE 130000Z TAFS/... ISSUED AT 646 PM EDT WED MAR 12 2014 HIGH PRESSURE WILL BUILD ACROSS THE AREA TONIGHT AND SUBSIDENCE RETURNS. ASIDE FROM SOME LINGERING MFVR FOR SITES SUCH AS KIND/KHUF/KLAF THROUGH 02Z...FORECAST SOUNDINGS INDICATE A DRY COLUMN...THUS WILL TREND TOWARD VFR OVERNIGHT. SOME GOOD WARM AIR ADVECTION IS EXPECTED ON THURSDAY AND THIS SHOULD RESULT IN SOME MID TO HIGH CLOUDS ACROSS THE AREA....BUT STILL VFR CONDITIONS. && .IND WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...RYAN NEAR TERM...RYAN/50 SHORT TERM...RYAN LONG TERM....PUMA AVIATION...SMF VISIT US AT HTTP://WWW.WEATHER.GOV/IND FOLLOW US ON TWITTER AND YOUTUBE AT: WWW.TWITTER.COM/NWSINDIANAPOLIS WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
649 PM EDT WED MAR 12 2014 .UPDATE... THE AVIATION SECTION HAS BEEN UPDATED BELOW. && .SYNOPSIS... ISSUED AT 321 PM EDT WED MAR 12 2014 MUCH COLDER AIR WILL RETURN INTO THE REGION TONIGHT WITH HIGH PRESSURE. THE CHILLY WEATHER WILL BE SHORT-LIVED...AS THE PASSAGE OF A WARM FRONT THURSDAY NIGHT WILL USHER IN MILDER TEMPERATURES FRIDAY. AFTER A WEAK COLD FRONT BRINGS A CHANCE FOR LIGHT RAIN FRIDAY NIGHT...COOLER WEATHER WILL RETURN INTO EARLY NEXT WEEK. && .NEAR TERM /TONIGHT/... ISSUED AT 321 PM EDT WED MAR 12 2014 BACK EDGE OF THE LIGHT SNOW ASSOCIATED WITH THE LOW PRESSURE MOVING ACROSS THE EASTERN HALF OF THE FORECAST AREA AS OF 19Z. ANOTHER AREA OF WHAT APPEARS TO BE CONVECTIVE SNOW SHOWERS OVER NORTHERN/CENTRAL ILLINOIS ASSOCIATED WITH AN UPPER LEVEL WAVE CONTINUES TO MOVE SLOWLY SOUTHEAST. TEMPS HAVE BEEN GENERALLY STEADY-STATE IN THE LOWER/MID 30S OVER THE LAST FEW HOURS. WENT AHEAD AND DROPPED BOTH HEADLINES /WINTER WEATHER AND WIND ADVISORIES/ AS SNOW HAS LIGHTENED CONSIDERABLY AND WIND GUSTS HAVE DROPPED BELOW 40MPH. ADDITIONALLY...WITH A GENERALLY HEAVY WET SNOW IN THE LOCATIONS WHERE SOME ACCUMULATION WAS EXPERIENCED...THE BLOWING SNOW CONCERNS HAVE BEEN GREATLY DIMINISHED. INITIAL ISSUE FOCUSES ON THE AREA OF SNOW OVER ILLINOIS. MOST SHORT RANGE MODEL GUIDANCE STRUGGLING WITH THIS...BUT HRRR HINTS AT BRINGING THE AXIS OF SNOW ACROSS THE LOWER WABASH VALLEY INTO THE EVENING. ADDITIONALLY...RAP SOUNDINGS SHOWING SUBTLE INSTABILITY PRESENT FOR THE NEXT FEW HOURS. WILL PUT LOW CHANCE POPS IN THROUGH MID EVENING FROM TERRE HAUTE TO WASHINGTON AND POINTS WEST. EVEN THOUGH MAY HAVE BRIEF BURSTS OF HEAVIER SNOW SHOWERS WITHIN CONVECTION...SURFACE/GROUND TEMPS ARE ABOVE FREEZING AND EXPECT IMPACTS TO BE MINIMAL. REMAINDER OF THE FORECAST IS QUIET FOR TONIGHT AS WEAK HIGH PRESSURE BUILDS IN OVERNIGHT. EXPECT SKIES TO BECOME CLEAR TONIGHT WITH WIND GUSTS DIMINISHING DURING THE EVENING AS THE SURFACE PRESSURE GRADIENT RELAXES. TEMPS...COLD NIGHT BY MARCH STANDARDS AS CLEAR SKIES WITH A FRESH SNOWPACK OVER NORTHERN COUNTIES SHOULD ENABLE TEMPS TO TUMBLE INTO THE SINGLE DIGITS. EVEN FOR THE REMAINDER OF THE FORECAST AREA THAT IS FREE OF SNOW COVER...EXPECT TEMPS TO BOTTOM OUT IN THE TEENS. GENERALLY WENT WITH WARMER MAVMOS IN SNOW-FREE AREAS...AND MUCH CLOSER TO COLDER METMOS OVER NORTHERN COUNTIES. && .SHORT TERM /THURSDAY THROUGH SATURDAY/... ISSUED AT 321 PM EDT WED MAR 12 2014 FORECAST CHALLENGES FOCUS ON PRECIP CHANCES WITH A WEAK FRONT LATE FRIDAY...AND TEMPS THROUGHOUT THE FORECAST PERIOD. THE FRENETIC PACE TO WEATHER ACROSS THE REGION AS OF LATE WILL CONTINUE THROUGH THE PERIOD...WITH THIS BRIEF RETURN TO WINTER FOLLOWED BY YET ANOTHER REMINDER BY FRIDAY THAT SPRING IS DEFINITELY ON THE HORIZON. COLD BUT SUNNY START ON THURSDAY WITH HIGH PRESSURE RIDGE OVER THE OHIO VALLEY. THE SURFACE RIDGE WILL SHIFT EAST QUICKLY BY THURSDAY AFTERNOON WITH INCREASING LOW LEVEL WARM ADVECTION COMMENCING BY LATE DAY...FOLLOWED BY THE PASSAGE OF A DRY WARM FRONT THURSDAY NIGHT. EXPECT A PERIOD WITH INCREASED MID/HIGH LEVEL CLOUDS THURSDAY AFTERNOON AND EVENING IMMEDIATELY AHEAD OF THE WARM FRONT...WITH SKIES CLEARING OVERNIGHT. RETURN OF RIDGING ALOFT ON FRIDAY AND SOUTHWEST FLOW AHEAD OF AN APPROACHING WEAK COLD FRONT WILL SET THE STAGE FOR A MILD YET WINDY DAY. LOW LEVEL JET WILL OVERSPREAD THE REGION BY FRIDAY AFTERNOON AHEAD OF THE FRONT AND WITH MODEST MIXING LEVELS UP TO ABOUT 3KFT...SHOULD HAVE NO PROBLEM PULLING SOME STRONGER GUSTS TO 30-35MPH DOWN TO THE SURFACE. THE FRONT WILL INITIALLY BE LACKING MOISTURE BUT AS IT MOVES INTO THE OHIO VALLEY FRIDAY EVENING...IT WILL TAP INTO A SLIGHTLY BETTER FETCH OF GULF MOISTURE. COMBINED WITH AN AXIS OF LOW LEVEL CONVERGENCE ALONG THE FRONT AND A BRIEF YET SUBTLE PERIOD OF ISENTROPIC LIFT...EXPECT A FEW LIGHT RAIN SHOWERS TO DEVELOP FRIDAY EVENING...SHIFTING SOUTH OF THE FORECAST AREA PRIOR TO DAYBREAK SATURDAY. THE DEEPER MOISTURE DEPARTS AHEAD OF THE COLDER AIR...SO ANTICIPATE PRECIP TO FALL ENTIRELY AS LIGHT RAIN. WEAK HIGH PRESSURE WILL THEN REESTABLISH FOR SATURDAY WITH DRY WEATHER AND SLIGHTLY COOLER TEMPS. TEMPS...ARRIVAL OF WARM ADVECTION BY AFTERNOON SHOULD ENABLE A NICE RECOVERY THURS WITH HIGHS INTO THE 30S. MAVMOS IN PARTICULAR APPEARS TO BE A LITTLE TOO AGGRESSIVE WITH THE WARMUP...AND UNDERCUT BY A FEW DEGREES IN GENERAL. FOLLOWED THE RECENT TREND OF GOING ABOVE MOS FOR HIGHS FRIDAY AS COMBINATION OF WARM ADVECTION...SOUTHWEST FLOW AND COMPRESSIONAL HEATING AHEAD OF THE FRONT WILL ALLOW TEMPS TO APPROACH 60 ACROSS ALL BUT NORTHERN COUNTIES. MOS LOOKED REASONABLE FOR HIGHS SATURDAY GENERALLY IN THE UPPER 40S AND 50S. BOUNDARY LAYER THERMALS SUPPORTED MOS GUIDANCE FOR LOWS THROUGH THE PERIOD. && .LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/... ISSUED AT 149 PM EDT WED MAR 12 2014 HIGH VARIABILITY AND LOW CONFIDENCE DURING THIS PERIOD AS MODELS SUGGEST SEVERAL WEAKER SYSTEMS PASSING THROUGH THE AREA ALBEIT WITH LIMITED MOISTURE. GFS PUSHES SOME UPPER SUPPORT AND A WEAK TROUGH THROUGH THE AREA ON MONDAY...HOWEVER MOISTURE REMAINS LIMITED AND CONFIDENCE IS LOW AS THE ECMWF PUSHES BETTER SUPPORT THROUGH DEEP SOUTH. A WARMING TREND IS NOTED THROUGH THE PERIOD AS STRONG WARM AIR ADVECTION IS SEEN IN THE GFS ON TUE THROUGH WEDNESDAY. A THERMAL RIDGE ACTUALLY BUILD ACROSS ILLINOIS AND INDIANA WITH 850MB TEMPS RISING TOWARD 11C. THIS SHOULD PRODUCE SOME TEMPS AT OR ABOVE NORMALS. HAVE INCLUDED A CHC FOR RAIN ON WEDNESDAY AS A GFS SUGGEST A COLD FRONTAL PASSAGE...STILL VERY LOW CONFIDENCE. && .AVIATION /DISCUSSION FOR THE 130000Z TAFS/... ISSUED AT 646 PM EDT WED MAR 12 2014 HIGH PRESSURE WILL BUILD ACROSS THE AREA TONIGHT AND SUBSIDENCE RETURNS. ASIDE FROM SOME LINGERING MFVR FOR SITES SUCH AS KIND/KHUF/KLAF THROUGH 02Z...FORECAST SOUNDINGS INDICATE A DRY COLUMN...THUS WILL TREND TOWARD VFR OVERNIGHT. SOME GOOD WARM AIR ADVECTION IS EXPECTED ON THURSDAY AND THIS SHOULD RESULT IN SOME MID TO HIGH CLOUDS ACROSS THE AREA....BUT STILL VFR CONDITIONS. && .IND WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...RYAN NEAR TERM...RYAN SHORT TERM...RYAN LONG TERM....PUMA AVIATION...SMF VISIT US AT HTTP://WWW.WEATHER.GOV/IND FOLLOW US ON TWITTER AND YOUTUBE AT: WWW.TWITTER.COM/NWSINDIANAPOLIS WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
422 PM EDT WED MAR 12 2014 .UPDATE... THE AVIATION SECTION HAS BEEN UPDATED BELOW. && .SYNOPSIS... ISSUED AT 321 PM EDT WED MAR 12 2014 MUCH COLDER AIR WILL RETURN INTO THE REGION TONIGHT WITH HIGH PRESSURE. THE CHILLY WEATHER WILL BE SHORT-LIVED...AS THE PASSAGE OF A WARM FRONT THURSDAY NIGHT WILL USHER IN MILDER TEMPERATURES FRIDAY. AFTER A WEAK COLD FRONT BRINGS A CHANCE FOR LIGHT RAIN FRIDAY NIGHT...COOLER WEATHER WILL RETURN INTO EARLY NEXT WEEK. && .NEAR TERM /TONIGHT/... ISSUED AT 321 PM EDT WED MAR 12 2014 BACK EDGE OF THE LIGHT SNOW ASSOCIATED WITH THE LOW PRESSURE MOVING ACROSS THE EASTERN HALF OF THE FORECAST AREA AS OF 19Z. ANOTHER AREA OF WHAT APPEARS TO BE CONVECTIVE SNOW SHOWERS OVER NORTHERN/CENTRAL ILLINOIS ASSOCIATED WITH AN UPPER LEVEL WAVE CONTINUES TO MOVE SLOWLY SOUTHEAST. TEMPS HAVE BEEN GENERALLY STEADY-STATE IN THE LOWER/MID 30S OVER THE LAST FEW HOURS. WENT AHEAD AND DROPPED BOTH HEADLINES /WINTER WEATHER AND WIND ADVISORIES/ AS SNOW HAS LIGHTENED CONSIDERABLY AND WIND GUSTS HAVE DROPPED BELOW 40MPH. ADDITIONALLY...WITH A GENERALLY HEAVY WET SNOW IN THE LOCATIONS WHERE SOME ACCUMULATION WAS EXPERIENCED...THE BLOWING SNOW CONCERNS HAVE BEEN GREATLY DIMINISHED. INITIAL ISSUE FOCUSES ON THE AREA OF SNOW OVER ILLINOIS. MOST SHORT RANGE MODEL GUIDANCE STRUGGLING WITH THIS...BUT HRRR HINTS AT BRINGING THE AXIS OF SNOW ACROSS THE LOWER WABASH VALLEY INTO THE EVENING. ADDITIONALLY...RAP SOUNDINGS SHOWING SUBTLE INSTABILITY PRESENT FOR THE NEXT FEW HOURS. WILL PUT LOW CHANCE POPS IN THROUGH MID EVENING FROM TERRE HAUTE TO WASHINGTON AND POINTS WEST. EVEN THOUGH MAY HAVE BRIEF BURSTS OF HEAVIER SNOW SHOWERS WITHIN CONVECTION...SURFACE/GROUND TEMPS ARE ABOVE FREEZING AND EXPECT IMPACTS TO BE MINIMAL. REMAINDER OF THE FORECAST IS QUIET FOR TONIGHT AS WEAK HIGH PRESSURE BUILDS IN OVERNIGHT. EXPECT SKIES TO BECOME CLEAR TONIGHT WITH WIND GUSTS DIMINISHING DURING THE EVENING AS THE SURFACE PRESSURE GRADIENT RELAXES. TEMPS...COLD NIGHT BY MARCH STANDARDS AS CLEAR SKIES WITH A FRESH SNOWPACK OVER NORTHERN COUNTIES SHOULD ENABLE TEMPS TO TUMBLE INTO THE SINGLE DIGITS. EVEN FOR THE REMAINDER OF THE FORECAST AREA THAT IS FREE OF SNOW COVER...EXPECT TEMPS TO BOTTOM OUT IN THE TEENS. GENERALLY WENT WITH WARMER MAVMOS IN SNOW-FREE AREAS...AND MUCH CLOSER TO COLDER METMOS OVER NORTHERN COUNTIES. && .SHORT TERM /THURSDAY THROUGH SATURDAY/... ISSUED AT 321 PM EDT WED MAR 12 2014 FORECAST CHALLENGES FOCUS ON PRECIP CHANCES WITH A WEAK FRONT LATE FRIDAY...AND TEMPS THROUGHOUT THE FORECAST PERIOD. THE FRENETIC PACE TO WEATHER ACROSS THE REGION AS OF LATE WILL CONTINUE THROUGH THE PERIOD...WITH THIS BRIEF RETURN TO WINTER FOLLOWED BY YET ANOTHER REMINDER BY FRIDAY THAT SPRING IS DEFINITELY ON THE HORIZON. COLD BUT SUNNY START ON THURSDAY WITH HIGH PRESSURE RIDGE OVER THE OHIO VALLEY. THE SURFACE RIDGE WILL SHIFT EAST QUICKLY BY THURSDAY AFTERNOON WITH INCREASING LOW LEVEL WARM ADVECTION COMMENCING BY LATE DAY...FOLLOWED BY THE PASSAGE OF A DRY WARM FRONT THURSDAY NIGHT. EXPECT A PERIOD WITH INCREASED MID/HIGH LEVEL CLOUDS THURSDAY AFTERNOON AND EVENING IMMEDIATELY AHEAD OF THE WARM FRONT...WITH SKIES CLEARING OVERNIGHT. RETURN OF RIDGING ALOFT ON FRIDAY AND SOUTHWEST FLOW AHEAD OF AN APPROACHING WEAK COLD FRONT WILL SET THE STAGE FOR A MILD YET WINDY DAY. LOW LEVEL JET WILL OVERSPREAD THE REGION BY FRIDAY AFTERNOON AHEAD OF THE FRONT AND WITH MODEST MIXING LEVELS UP TO ABOUT 3KFT...SHOULD HAVE NO PROBLEM PULLING SOME STRONGER GUSTS TO 30-35MPH DOWN TO THE SURFACE. THE FRONT WILL INITIALLY BE LACKING MOISTURE BUT AS IT MOVES INTO THE OHIO VALLEY FRIDAY EVENING...IT WILL TAP INTO A SLIGHTLY BETTER FETCH OF GULF MOISTURE. COMBINED WITH AN AXIS OF LOW LEVEL CONVERGENCE ALONG THE FRONT AND A BRIEF YET SUBTLE PERIOD OF ISENTROPIC LIFT...EXPECT A FEW LIGHT RAIN SHOWERS TO DEVELOP FRIDAY EVENING...SHIFTING SOUTH OF THE FORECAST AREA PRIOR TO DAYBREAK SATURDAY. THE DEEPER MOISTURE DEPARTS AHEAD OF THE COLDER AIR...SO ANTICIPATE PRECIP TO FALL ENTIRELY AS LIGHT RAIN. WEAK HIGH PRESSURE WILL THEN REESTABLISH FOR SATURDAY WITH DRY WEATHER AND SLIGHTLY COOLER TEMPS. TEMPS...ARRIVAL OF WARM ADVECTION BY AFTERNOON SHOULD ENABLE A NICE RECOVERY THURS WITH HIGHS INTO THE 30S. MAVMOS IN PARTICULAR APPEARS TO BE A LITTLE TOO AGGRESSIVE WITH THE WARMUP...AND UNDERCUT BY A FEW DEGREES IN GENERAL. FOLLOWED THE RECENT TREND OF GOING ABOVE MOS FOR HIGHS FRIDAY AS COMBINATION OF WARM ADVECTION...SOUTHWEST FLOW AND COMPRESSIONAL HEATING AHEAD OF THE FRONT WILL ALLOW TEMPS TO APPROACH 60 ACROSS ALL BUT NORTHERN COUNTIES. MOS LOOKED REASONABLE FOR HIGHS SATURDAY GENERALLY IN THE UPPER 40S AND 50S. BOUNDARY LAYER THERMALS SUPPORTED MOS GUIDANCE FOR LOWS THROUGH THE PERIOD. && .LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/... ISSUED AT 149 PM EDT WED MAR 12 2014 HIGH VARIABILITY AND LOW CONFIDENCE DURING THIS PERIOD AS MODELS SUGGEST SEVERAL WEAKER SYSTEMS PASSING THROUGH THE AREA ALBEIT WITH LIMITED MOISTURE. GFS PUSHES SOME UPPER SUPPORT AND A WEAK TROUGH THROUGH THE AREA ON MONDAY...HOWEVER MOISTURE REMAINS LIMITED AND CONFIDENCE IS LOW AS THE ECMWF PUSHES BETTER SUPPORT THROUGH DEEP SOUTH. A WARMING TREND IS NOTED THROUGH THE PERIOD AS STRONG WARM AIR ADVECTION IS SEEN IN THE GFS ON TUE THROUGH WEDNESDAY. A THERMAL RIDGE ACTUALLY BUILD ACROSS ILLINOIS AND INDIANA WITH 850MB TEMPS RISING TOWARD 11C. THIS SHOULD PRODUCE SOME TEMPS AT OR ABOVE NORMALS. HAVE INCLUDED A CHC FOR RAIN ON WEDNESDAY AS A GFS SUGGEST A COLD FRONTAL PASSAGE...STILL VERY LOW CONFIDENCE. && .AVIATION /DISCUSSION FOR THE 121800Z TAFS/... ISSUED AT 419 PM EDT WED MAR 12 2014 2020Z UPDATE...KIND IS CURRENTLY VFR AND TRENDS ARE FOR THIS TO BECOME PREDOMINATE OVER THE NEXT FEW HOURS. HOWEVER SOME MFVR CLOUDS MAY CONTINUE TO DRIFT THROUGH BEFORE 00Z SO A BKN DECK AROUND 025 WAS TEMPO/D IN FOR THE NEXT FEW HOURS. OTHER TAFS LOOK GOOD. NO OTHER CHANGES NEEDED AT THIS TIME. PREVIOUS DISCUSSION FOLLOWS. RADAR RETURNS OVER THE AREA SHOW RETURNS DIMINISHING AND QUICKLY MOVING EAST...EXITING THE AREA. AS SNOW WAS EXITING CEILINGS WERE BECOMING MVFR. THUS AS THE BACK EDGE OF THE CLOUD SHIELD WITH THE DEPARTING LOW PASSES ACROSS THE AREA...EXPECT MVFR CEILINGS TO PERSIST THE NEXT 6 HOURS. HIGH PRESSURE IS THEN EXPECTED TO BUILD ACROSS THE AREA TONIGHT AND SUBSIDENCE RETURNS. FORECAST SOUNDINGS INDICATE A DRY COLUMN...THUS WILL TREND TOWARD VFR OVERNIGHT. SOME GOOD WARM AIR ADVECTION IS EXPECTED ON THURSDAY AND THIS SHOULD RESULT IN SOME HIGH CLOUDS ACROSS THE AREA....BUT STILL VFR CONDITIONS. && .IND WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...RYAN NEAR TERM...RYAN SHORT TERM...RYAN LONG TERM....PUMA AVIATION...SMF VISIT US AT HTTP://WWW.WEATHER.GOV/IND FOLLOW US ON TWITTER AND YOUTUBE AT: WWW.TWITTER.COM/NWSINDIANAPOLIS WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
321 PM EDT WED MAR 12 2014 .UPDATE... THE SYNOPSIS...NEAR TERM AND SHORT TERM SECTIONS HAVE BEEN UPDATED BELOW. && .SYNOPSIS... ISSUED AT 321 PM EDT WED MAR 12 2014 MUCH COLDER AIR WILL RETURN INTO THE REGION TONIGHT WITH HIGH PRESSURE. THE CHILLY WEATHER WILL BE SHORT-LIVED...AS THE PASSAGE OF A WARM FRONT THURSDAY NIGHT WILL USHER IN MILDER TEMPERATURES FRIDAY. AFTER A WEAK COLD FRONT BRINGS A CHANCE FOR LIGHT RAIN FRIDAY NIGHT...COOLER WEATHER WILL RETURN INTO EARLY NEXT WEEK. && .NEAR TERM /TONIGHT/... ISSUED AT 321 PM EDT WED MAR 12 2014 BACK EDGE OF THE LIGHT SNOW ASSOCIATED WITH THE LOW PRESSURE MOVING ACROSS THE EASTERN HALF OF THE FORECAST AREA AS OF 19Z. ANOTHER AREA OF WHAT APPEARS TO BE CONVECTIVE SNOW SHOWERS OVER NORTHERN/CENTRAL ILLINOIS ASSOCIATED WITH AN UPPER LEVEL WAVE CONTINUES TO MOVE SLOWLY SOUTHEAST. TEMPS HAVE BEEN GENERALLY STEADY-STATE IN THE LOWER/MID 30S OVER THE LAST FEW HOURS. WENT AHEAD AND DROPPED BOTH HEADLINES /WINTER WEATHER AND WIND ADVISORIES/ AS SNOW HAS LIGHTENED CONSIDERABLY AND WIND GUSTS HAVE DROPPED BELOW 40MPH. ADDITIONALLY...WITH A GENERALLY HEAVY WET SNOW IN THE LOCATIONS WHERE SOME ACCUMULATION WAS EXPERIENCED...THE BLOWING SNOW CONCERNS HAVE BEEN GREATLY DIMINISHED. INITIAL ISSUE FOCUSES ON THE AREA OF SNOW OVER ILLINOIS. MOST SHORT RANGE MODEL GUIDANCE STRUGGLING WITH THIS...BUT HRRR HINTS AT BRINGING THE AXIS OF SNOW ACROSS THE LOWER WABASH VALLEY INTO THE EVENING. ADDITIONALLY...RAP SOUNDINGS SHOWING SUBTLE INSTABILITY PRESENT FOR THE NEXT FEW HOURS. WILL PUT LOW CHANCE POPS IN THROUGH MID EVENING FROM TERRE HAUTE TO WASHINGTON AND POINTS WEST. EVEN THOUGH MAY HAVE BRIEF BURSTS OF HEAVIER SNOW SHOWERS WITHIN CONVECTION...SURFACE/GROUND TEMPS ARE ABOVE FREEZING AND EXPECT IMPACTS TO BE MINIMAL. REMAINDER OF THE FORECAST IS QUIET FOR TONIGHT AS WEAK HIGH PRESSURE BUILDS IN OVERNIGHT. EXPECT SKIES TO BECOME CLEAR TONIGHT WITH WIND GUSTS DIMINISHING DURING THE EVENING AS THE SURFACE PRESSURE GRADIENT RELAXES. TEMPS...COLD NIGHT BY MARCH STANDARDS AS CLEAR SKIES WITH A FRESH SNOWPACK OVER NORTHERN COUNTIES SHOULD ENABLE TEMPS TO TUMBLE INTO THE SINGLE DIGITS. EVEN FOR THE REMAINDER OF THE FORECAST AREA THAT IS FREE OF SNOW COVER...EXPECT TEMPS TO BOTTOM OUT IN THE TEENS. GENERALLY WENT WITH WARMER MAVMOS IN SNOW-FREE AREAS...AND MUCH CLOSER TO COLDER METMOS OVER NORTHERN COUNTIES. && .SHORT TERM /THURSDAY THROUGH SATURDAY/... ISSUED AT 321 PM EDT WED MAR 12 2014 FORECAST CHALLENGES FOCUS ON PRECIP CHANCES WITH A WEAK FRONT LATE FRIDAY...AND TEMPS THROUGHOUT THE FORECAST PERIOD. THE FRENETIC PACE TO WEATHER ACROSS THE REGION AS OF LATE WILL CONTINUE THROUGH THE PERIOD...WITH THIS BRIEF RETURN TO WINTER FOLLOWED BY YET ANOTHER REMINDER BY FRIDAY THAT SPRING IS DEFINITELY ON THE HORIZON. COLD BUT SUNNY START ON THURSDAY WITH HIGH PRESSURE RIDGE OVER THE OHIO VALLEY. THE SURFACE RIDGE WILL SHIFT EAST QUICKLY BY THURSDAY AFTERNOON WITH INCREASING LOW LEVEL WARM ADVECTION COMMENCING BY LATE DAY...FOLLOWED BY THE PASSAGE OF A DRY WARM FRONT THURSDAY NIGHT. EXPECT A PERIOD WITH INCREASED MID/HIGH LEVEL CLOUDS THURSDAY AFTERNOON AND EVENING IMMEDIATELY AHEAD OF THE WARM FRONT...WITH SKIES CLEARING OVERNIGHT. RETURN OF RIDGING ALOFT ON FRIDAY AND SOUTHWEST FLOW AHEAD OF AN APPROACHING WEAK COLD FRONT WILL SET THE STAGE FOR A MILD YET WINDY DAY. LOW LEVEL JET WILL OVERSPREAD THE REGION BY FRIDAY AFTERNOON AHEAD OF THE FRONT AND WITH MODEST MIXING LEVELS UP TO ABOUT 3KFT...SHOULD HAVE NO PROBLEM PULLING SOME STRONGER GUSTS TO 30-35MPH DOWN TO THE SURFACE. THE FRONT WILL INITIALLY BE LACKING MOISTURE BUT AS IT MOVES INTO THE OHIO VALLEY FRIDAY EVENING...IT WILL TAP INTO A SLIGHTLY BETTER FETCH OF GULF MOISTURE. COMBINED WITH AN AXIS OF LOW LEVEL CONVERGENCE ALONG THE FRONT AND A BRIEF YET SUBTLE PERIOD OF ISENTROPIC LIFT...EXPECT A FEW LIGHT RAIN SHOWERS TO DEVELOP FRIDAY EVENING...SHIFTING SOUTH OF THE FORECAST AREA PRIOR TO DAYBREAK SATURDAY. THE DEEPER MOISTURE DEPARTS AHEAD OF THE COLDER AIR...SO ANTICIPATE PRECIP TO FALL ENTIRELY AS LIGHT RAIN. WEAK HIGH PRESSURE WILL THEN REESTABLISH FOR SATURDAY WITH DRY WEATHER AND SLIGHTLY COOLER TEMPS. TEMPS...ARRIVAL OF WARM ADVECTION BY AFTERNOON SHOULD ENABLE A NICE RECOVERY THURS WITH HIGHS INTO THE 30S. MAVMOS IN PARTICULAR APPEARS TO BE A LITTLE TOO AGGRESSIVE WITH THE WARMUP...AND UNDERCUT BY A FEW DEGREES IN GENERAL. FOLLOWED THE RECENT TREND OF GOING ABOVE MOS FOR HIGHS FRIDAY AS COMBINATION OF WARM ADVECTION...SOUTHWEST FLOW AND COMPRESSIONAL HEATING AHEAD OF THE FRONT WILL ALLOW TEMPS TO APPROACH 60 ACROSS ALL BUT NORTHERN COUNTIES. MOS LOOKED REASONABLE FOR HIGHS SATURDAY GENERALLY IN THE UPPER 40S AND 50S. BOUNDARY LAYER THERMALS SUPPORTED MOS GUIDANCE FOR LOWS THROUGH THE PERIOD. && .LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/... ISSUED AT 149 PM EDT WED MAR 12 2014 HIGH VARIABILITY AND LOW CONFIDENCE DURING THIS PERIOD AS MODELS SUGGEST SEVERAL WEAKER SYSTEMS PASSING THROUGH THE AREA ALBEIT WITH LIMITED MOISTURE. GFS PUSHES SOME UPPER SUPPORT AND A WEAK TROUGH THROUGH THE AREA ON MONDAY...HOWEVER MOISTURE REMAINS LIMITED AND CONFIDENCE IS LOW AS THE ECMWF PUSHES BETTER SUPPORT THROUGH DEEP SOUTH. A WARMING TREND IS NOTED THROUGH THE PERIOD AS STRONG WARM AIR ADVECTION IS SEEN IN THE GFS ON TUE THROUGH WEDNESDAY. A THERMAL RIDGE ACTUALLY BUILD ACROSS ILLINOIS AND INDIANA WITH 850MB TEMPS RISING TOWARD 11C. THIS SHOULD PRODUCE SOME TEMPS AT OR ABOVE NORMALS. HAVE INCLUDED A CHC FOR RAIN ON WEDNESDAY AS A GFS SUGGEST A COLD FRONTAL PASSAGE...STILL VERY LOW CONFIDENCE. && .AVIATION /DISCUSSION FOR THE 121800Z TAFS/... ISSUED AT 1250 PM EDT WED MAR 12 2014 RADAR RETURNS OVER THE AREA SHOW RETURNS DIMINISHING AND QUICKLY MOVING EAST...EXITING THE AREA. AS SNOW WAS EXITING CEILINGS WERE BECOMING MVFR. THUS AS THE BACK EDGE OF THE CLOUD SHIELD WITH THE DEPARTING LOW PASSES ACROSS THE AREA...EXPECT MVFR CEILINGS TO PERSIST THE NEXT 6 HOURS. HIGH PRESSURE IS THEN EXPECTED TO BUILD ACROSS THE AREA TONIGHT AND SUBSIDENCE RETURNS. FORECAST SOUNDINGS INDICATE A DRY COLUMN...THUS WILL TREND TOWARD VFR OVERNIGHT. SOME GOOD WARM AIR ADVECTION IS EXPECTED ON THURSDAY AND THIS SHOULD RESULT IN SOME HIGH CLOUDS ACROSS THE AREA....BUT STILL VFR CONDITIONS. && .IND WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SYNOPSIS...RYAN NEAR TERM...RYAN SHORT TERM...RYAN LONG TERM....PUMA AVIATION...JP VISIT US AT HTTP://WWW.WEATHER.GOV/IND FOLLOW US ON TWITTER AND YOUTUBE AT: WWW.TWITTER.COM/NWSINDIANAPOLIS WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
325 PM EDT WED MAR 12 2014 .SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT) ISSUED AT 315 PM EDT WED MAR 12 2014 18Z SFC ANALYSIS SHOWS THE DEEP LOW NOW OVER SOUTHWESTERN PENNSYLVANIA WITH ITS COLD FRONT EAST OF KENTUCKY. THIS FRONT WAS ACCOMPANIED AND TRAILED BY THE HIGHEST WINDS OF THE DAY WITH MANY GUSTS TO 45 AND 50 MPH REPORTED IN ADDITION TO A 54 MPH GUST AT THE KNOTT COUNTY MESONET. THE WINDS WILL CONTINUE GUSTY INTO THE EVENING AS THE COLD AIR CONTINUES TO POUR INTO THIS PART OF THE STATE. THESE WINDS ARE BRINGING IN THE SOON TO BE SUB FREEZING AIR WITH MID 30S ALREADY NOTED IN THE NORTHWEST PARTS OF THE AREA WHILE MID 40S HOLD IN THE FAR EAST...THOUGH BLACK MOUNTAIN IS DOWN TO 38 DEGREES. DEWPOINTS ARE IN THE LOWER 30S NORTH TO THE UPPER 30S ACROSS THE SOUTHEAST. THE UPSLOPE FLOW IS KICKING IN ACROSS THE AREA AND WE CAN SEE THE RAIN SHOWERS REDEVELOPING THROUGH THE HEART OF THE CWA. SOME FLURRIES HAVE BEEN REPORTED WITH THESE HERE AT JKL...AND ALSO IN OUR NORTHERN FRINGES...ON TRACK WITH EXPECTATIONS AND TIMING FROM THE LATEST HRRR. THIS MODEL ALSO HAS BETTER REDEVELOPMENT OF SNOW TOWARD DUSK. AFTER REVIEWING THE LATEST MODEL GUIDANCE...AND IN PARTICULAR THE HRRR...HAVE DECIDED TO HOIST A WINTER WEATHER ADVISORY FOR THREE OF OUR NORTHERN BORDER COUNTIES WITH VIRGINIA FOR A 1 TO 2 INCH SNOWFALL MAINLY AT ELEVATIONS ABOVE 2500 FEET. THE MODELS ARE IN GOOD AGREEMENT ALOFT WITH THE DEEP LATE WINTER TROUGH CROSSING THE OHIO VALLEY TONIGHT. THEY ALL HAVE ENERGY WRAPPING IN HERE THROUGH 12Z THURSDAY BEFORE THE MASS OF IT PULLS OFF THE EAST AND HEIGHTS QUICKLY RISE DURING THE DAY THURSDAY. THESE HEIGHTS FLATTEN OUT LATER THURSDAY NIGHT AS A SHALLOW TROUGH MOVES THIS WAY FROM THE NORTHERN PLAINS. WITH THIS GOOD AGREEMENT...AND THE ONGOING WINTER STORM...HAVE LEANED MOST HEAVILY ON THE HIGHER RESOLUTION NAM12 AND HRRR FOR WEATHER DETAILS. SENSIBLE WEATHER WILL FEATURE THE UPSLOPE RAIN...CHANGING TO SNOW LATE THIS AFTERNOON AND EARLY EVENING AND THEN CONTINUING THROUGH THE EVENING FOR MOST LOCATIONS. THE SNOW WILL LINGER THE LONGEST IN THE FAR EASTERN PARTS OF THE AREA THROUGH THE MIDDLE OF THE NIGHT. LOOKING AT AN INCH OR LESS OF ACCUMULATION FOR MOST AREAS...WITH THOSE HIGHER TOTALS MAINLY ON THE RIDGES. DO EXPECT NEARLY ALL SPOTS TO GET A DUSTING OF SNOW EVEN IN THE VALLEYS...BUT THE LAG IN THE COOLING OF THE ROADS SHOULD KEEP THEM MOSTLY CLEAR. THE FAR SOUTHEAST PARTS OF THE CWA ARE A BIT DIFFERENT...THOUGH...AS THE UPSLOPE WILL HOLD IN LONGER THERE...TEMPERATURES ARE DROPPING OFF QUICKER IN THE HIGHER ELEVATIONS...THE HRRR IS HITTING THEM HARDEST WITH QPF...AND THEY HAVE HIGHER ELEVATION WELL TRAVELED ROADS. FOR THESE REASONS HAVE ISSUED A WSW FOR HARLAN...LETCHER...AND PIKE COUNTIES THROUGH 4Z...MATCHING UP WITH MRX IN WISE COUNTY. THE SNOW WILL TAPER TO FLURRIES AND END LATE TONIGHT AND EARLY THURSDAY MORNING FROM WEST TO EAST. TEMPERATURES WILL BOTTOM OUT IN THE UPPER TEENS MOST PLACES BY DAWN WITH STILL ENOUGH OF A BREEZE TO GENERATE WIND CHILLS IN THE SINGLE DIGITS OR NEAR ZERO ON THE HIGHEST RIDGES. THE LOW CLOUDS WILL CLEAR OUR LATER THURSDAY MORNING WITH SUNSHINE LIKELY EVAPORATING ANY OF THE SNOW FROM THIS SYSTEM BY MID AFTERNOON DESPITE TEMPERATURES STRUGGLING TO GET TOO DEEP INTO THE 30S. A PARTLY CLOUDY SKY ON THURSDAY NIGHT WILL SET THE STAGE FOR A MILDER NIGHT...BUT THIS WILL ALSO REPRESENT A DECENT RIDGE TO VALLEY TEMPERATURE SPLIT SET UP. USED A MODIFIED COLDER VERSION OF THE CONSSHORT FOR TEMPS DURING THE NEXT 24 HOURS AND THEN FAVORED THE NAM12 DIURNAL CURVE WITH ADJUSTED CONSALL MAX AND MIN T STARTING POINTS THROUGH FRIDAY MORNING. ALSO... USED THE BCCONSSHORT FOR TD AND WINDS WITH THE CONSALL AFTER THE FIRST 24 HOURS. THESE WERE MASSAGED FOR THE CURRENT CONDITIONS AND TRENDS. AS FOR POPS...ENDED UP ON THE HIGH SIDE OF ALL GUIDANCE GIVEN ITS POOR HISTORY OF PICKING UP ON LOW QPF UPSLOPE SNOW EVENTS. .LONG TERM...(FRIDAY THROUGH WEDNESDAY) ISSUED AT 325 PM EDT WED MAR 12 2014 SPLIT FLOW PATTERN WILL BE IN PLACE AT THE BEGINNING OF THE LONG TERM PORTION OF THE FORECAST WITH NEAR ZONAL FLOW ACROSS THE OH AND TN VALLEYS. AT THE SURFACE HIGH PRESSURE WILL BE TO OUR SOUTHEAST WITH SOUTHWEST LOW LEVEL FLOW ACROSS OUR AREA. AS A RESULT TEMPERATURES WILL WARM NICELY WITH MAXIMUM TEMPERATURES ON FRIDAY 20 TO 25 DEGREES WARMER THAN ON THURSDAY. AS WE MOVE INTO THE WEEKEND A SOUTHERN STREAM SHORT WAVE WILL EMERGE FROM THE SOUTHERN PLAINS WITH THE ASSOCIATED SURFACE LOW TRACKING ACROSS THE LOWER MS VALLEY AND THE SOUTHEAST UNITED STATES. AT THE SAME TIME A NORTHERN STREAM SHORT WAVE WILL BE DROPPING SE FROM THE NORTHERN PLAINS. THE COMBINED EFFECTS WILL BE TO BRING A CHANCE OF PRECIPITATION TO THE AREA FOR THE WEEKEND. THERE WILL ONLY BE LOW CHANCES OF PRECIPITATION ON SATURDAY...WITH PRECIPITATION CHANCES PEAKING ON SUNDAY. TEMPERATURES WILL BE WARM ENOUGH THAT ANY PRECIPITATION FROM FRIDAY NIGHT INTO SUNDAY WILL BE IN THE FORM OF RAIN. ENOUGH COLD AIR LOOKS TO WORK INTO THE AREA ON THE BACKSIDE OF THE SYSTEM SUNDAY NIGHT INTO EARLY MONDAY MORNING THAT PRECIPITATION COULD END AS SNOW. THERE IS NOT GOOD MODEL AGREEMENT AT THIS POINT IN TIME...BUT SOME LIGHT SNOW ACCUMULATION LOOKS POSSIBLE. THERE IS POOR MODEL AGREEMENT AS WE MOVE INTO NEXT WEEK AND CONFIDENCE IN THE VARIOUS MODEL SOLUTIONS DECREASES. AFTER A COLD START TO THE WEEK...TEMPERATURES WILL WARM...BUT THE WHEN AND WHERE OF THE NEXT SHORT WAVE TO AFFECT THE AREA ARE UNCERTAIN. FOR NOW WILL KEEP THE WEATHER DRY THROUGH TUESDAY NIGHT...AND BRING A SLIGHT CHANCE OF SHOWERS INTO THE FAR WESTERN PART OF THE FORECAST AREA ON WEDNESDAY. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON) ISSUED AT 205 PM EDT WED MAR 12 2014 LOW MVFR/IFR CIGS WILL AFFECT THE AREA INTO THE EVENING BEHIND THE COLD FRONT THAT JUST PASSED THROUGH. WITH THIS FROPA...WINDS HAVE SHIFTED TO THE WEST AND NORTHWEST AT BETWEEN 15 AND 25 KTS WITH WIND GUSTS CLOSER TO 35 KTS. LINGERING RAIN SHOWERS WILL CHANGEOVER TO SNOW SHOWERS FROM NORTHWEST TO SOUTHEAST BETWEEN 20 AND 00Z. FOLLOWING THIS...THERE WILL BE A PERIOD OF SNOW SHOWERS...LASTING LONGEST IN THE NORTHEAST PARTS OF THE FORECAST AREA. DURING THIS... CIGS AND VIS WILL BE IFR OR WORSE...FOR AT TIME. CEILINGS WILL GRADUALLY IMPROVE TOWARDS DAWN FROM WEST TO EAST WITH VFR CONDITIONS POSSIBLE BY MID MORNING THURSDAY. WINDS WILL SLACKEN LATER TONIGHT FROM THE NORTHWEST AND THEN CONTINUE AT 5 TO 10 KTS FROM THE WEST THROUGH THE DAY THURSDAY. && .JKL WATCHES/WARNINGS/ADVISORIES... WIND ADVISORY UNTIL 10 PM EDT THIS EVENING FOR KYZ044-050>052- 058>060-068-069-079-080-083>088-104-106>120. WINTER WEATHER ADVISORY FROM 8 PM THIS EVENING TO 4 AM EDT THURSDAY FOR KYZ088-118-120. && $$ SHORT TERM...GREIF LONG TERM...SBH AVIATION...GREIF
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
210 PM EDT WED MAR 12 2014 .UPDATE... ISSUED AT 210 PM EDT WED MAR 12 2014 DID A QUICK UPDATE TO THE GRIDS AND FORECAST TO REFLECT THE EXITING OF THE COLD FRONT AND REMOVE THE RISK OF THUNDER. ALSO...FINE TUNED POPS/WX AND TEMPERATURES THROUGH THE EVENING. THESE FRESHENED GRIDS HAVE BEEN SENT WITH THE ZFP AND HWO ALSO REVISED. UPDATE ISSUED AT 1055 AM EDT WED MAR 12 2014 14Z SFC ANALYSIS SHOWS A DEEP LOW PRESSURE AREA OFF TO OUR NORTHEAST WHILE ITS SHARP COLD FRONT IS NOW CUTTING INTO EAST KENTUCKY. THIS BOUNDARY SIGNALS THE DROPOFF IN THE TEMPERATURES AND ARRIVAL OF THE HIGHER WIND GUSTS...UP TO 45 MPH...ON WEST TO NORTHWEST WINDS. OVER EAST KENTUCKY THE SOUTHWEST WINDS AHEAD OF THE BOUNDARY HAVE MIXED THE COLDER VALLEYS OUT SO THAT MOST AREAS ARE NOW IN THE UPPER 50S AND LOWER 60S WHICH IS WHERE OUR HIGH TEMPS WILL END UP. DEWPOINTS HAVE SURGED AHEAD OF THE FRONT INTO THE MIDDLE AND UPPER 50S...AS WELL. THIS MAY BE GIVING JUST ENOUGH ENERGY TO GENERATE A RUMBLE OF THUNDER WITH THE FRONT. THEREAFTER...TEMPERATURES PLUMMET WITH A BIT OF A LULL IN THE STEADIER PCPN...THOUGH ANY LINGERING SHOWERS WILL CHANGE TO SNOW FROM NORTHWEST TO SOUTHEAST LATER THIS AFTERNOON... GENERALLY FROM 3 PM IN THE FAR NORTH TO 5 PM DOWN TO THE HAL ROGERS PARKWAY AND THE HIGHER TERRAIN IN THE FAR EAST. THE REST OF THE CWA SHOULD GO OVER TO SNOW OR BE COLD ENOUGH FOR ALL SNOW AROUND 6 PM. PER THE LATEST HRRR AND NAM12 THE SNOW SHOULD BE RATHER MEAGER THROUGH DARK BUT THEN KICK IN FOR SEVERAL HOURS MOST PLACES INTO MID EVENING BEFORE TAPERING OFF FROM WEST TO EAST. THE WINDS WILL KEEP THE SNOW BLOWING AROUND AND REDUCE VISIBILITY EVEN AS IT HAS TROUBLE ACCUMULATING ON THE STILL TEMPORARILY WARM ROADS. THIS WILL CHANGE WITH TIME...BUT MUCH OF THE SNOW WILL BE GONE BEFORE THE ROAD SFCS ARE COLD ENOUGH TO STICK. EVEN SO...WOULD NOT BE SURPRISED TO HEAR OF SLICK SPOTS AND LOW VISIBILITY ISSUES BETWEEN 7 AND 10 PM FOR MUCH OF THE AREA. THE SPS CURRENTLY HAS THIS ADDRESSED...BUT AN ADVISORY MAY BE WARRANTED IF WE SEE SIGNS OF BEEFIER SNOWS AND BETTER ACCUMULATIONS UPSTREAM. WILL CONTINUE TO MONITOR THIS. THE HIGHEST SNOW ACCUMULATIONS ARE EXPECTED OVER THE HIGHER TERRAIN IN THE FAR SOUTHEAST WITH UP TO 2 INCHES POSSIBLE ON THE PEAKS NEAR VIRGINA. AN ADVISORY THERE WOULD NOT BE A STRETCH AT THIS POINT...EITHER. WILL GIVE THE NEW GFS A GANDER BEFORE MAKING ANY FINAL DECISIONS...THOUGH. THE GRIDS HAVE BEEN UPDATED TO FINE TUNE THE FROPA...WINDS...AND CAA. THESE HAVE BEEN SENT TO THE NDFD AND WEB SERVERS. A ZFP UPDATE CAN BE ANTICIPATED ONCE THE FRONT IS THROUGH THE ENTIRE CWA IN AN HOUR OR SO TO CLEAR UP WORDING AND TIMING. UPDATE ISSUED AT 842 AM EDT WED MAR 12 2014 FRESHENED UP THE HOURLY TEMPERATURES...DEW POINTS...AND POPS ACCORDING TO THE LATEST TRENDS IN OBSERVATIONS AND RADAR. THE SURFACE COLD FRONT LOOKS TO BE ON OUR DOORSTEP JUST BEFORE 11 AM...WITH A DISTINCTIVE BREAK IN THE PRECIP BETWEEN SHOWERS AFFECTING OUR AREA RIGHT NOW AND THE FRONT. THERE IS ALSO ANOTHER BREAK IN THE ACTION BEHIND THE INITIAL COLD FRONT...BEFORE PRECIP FILLS IN ONCE AGAIN AT THE CUSP OF THE COLDER AIR. HAVE ATTEMPTED TO TIME ALL OF THIS A BIT BETTER FOR THE NEXT SEVERAL HOURS. IT DOES APPEAR THAT THE COLD AIR IS LAGGING JUST A TAD LATER. MOST OF THE STRONGER WIND GUSTS ARE OCCURRING ALONG AND BEHIND THE FRONT. UPDATES HAVE BEEN SENT. && .SHORT TERM...(TODAY THROUGH THURSDAY) ISSUED AT 344 AM EDT WED MAR 12 2014 THE LATEST SURFACE MAP FEATURES DEEPENING SURFACE LOW PRESSURE CURRENTLY CENTERED ACROSS SOUTHERN IL/IN. A SHARP COLD FRONT IS DRAPED FROM SOUTHEASTERN MO DOWN THROUGH EASTERN TX. HIGH PRESSURE EXTENDS FROM THE PACIFIC NORTHWEST DOWN ACROSS THE ROCKIES...SETTING UP A TIGHT PRESSURE GRADIENT ACROSS THE PLAINS. ALOFT...A WEAKENING SHORT WAVE TROUGH IS ROTATING OVER THE FLORIDA PANHANDLE. A DEEPER TROUGH IS MOVING INTO THE NORTHERN PLAINS/GREAT LAKES WITH A LEAD SHORT WAVE MOVING THROUGH MO/IL. EASTERN KENTUCKY REMAINS PLANTED IN THE WARM SECTOR...WITH MOST LOCATIONS REPORTING TEMPERATURES IN THE 50S AND LOW 60S...WHILE A FEW SHELTERED VALLEYS REMAIN DECOUPLED...REPORTING IN THE MID AND UPPER 40S. THE MODELS ARE IN GOOD AGREEMENT WITH THE SHORT TERM...WITH THE NORTHERN STREAM TROUGH AMPLIFYING ACROSS THE EASTERN CONUS THROUGH TONIGHT...AND ALLOWING THE SURFACE LOW TO CONTINUE TO INTENSIFY AS IT SLIDES ENE ALONG AND JUST NORTH OF THE OHIO RIVER TODAY...REACHING THE NORTHERN NEW ENGLAND COAST BY EARLY THURSDAY MORNING. THIS STRONG STORM SYSTEM WILL BRING MULTIPLE IMPACTS TO EASTERN KENTUCKY TODAY AND TONIGHT. WIDESPREAD SHOWERS...ALONG WITH AN ISOLATED THUNDERSTORM CAN BE EXPECTED TODAY. SURFACE WINDS WILL ALSO BECOME STRONG DURING THE DAY...FIRST OUT OF THE SOUTHWEST...AND THEN QUICKLY SHIFTING TO THE WEST AND NORTHWEST...AS THE COLD FRONT PLOWS THROUGH THE AREA BETWEEN 12 AND 4 PM. SUSTAINED SPEEDS RANGING FROM 15 TO 30 MPH...WITH GUSTS IN THE 35 TO 45 MPH RANGE STILL LOOK ON TARGET. AS COLDER AIR RUSHES IN BEHIND THE FRONT...RAIN SHOWERS WILL CHANGE OVER TO SNOW SHOWERS. THE MODELS HAVE TRENDED SOMEWHAT SLOWER WITH THE ARRIVAL OF THE COLDER AIR...PARTICULARLY THE NAM. HAVE ADJUSTED THE TIMING BACK A TAD...BUT STILL AHEAD OF THE MODELS...AS THEY TEND TO BE A LITTLE SLOW WITH THESE KINDS OF DYNAMIC SYSTEMS. AS SUCH...EXPECT THE CHANGEOVER CLOSER TO THE 2 TO 3 PM TIME FRAME IN THE BLUEGRASS...AND IN THE 5 TO 6 PM RANGE IN THE SOUTHEAST FOR MOST LOCATIONS. HAVE NOT ADJUSTED AMOUNTS MUCH FROM THE PREVIOUS FORECAST...WITH A HALF INCH OR LESS FOR VALLEYS...AND UP TO AN INCH FOR RIDGETOPS. WILL HAVE TO WATCH THE SOUTHEAST TERRAIN COUNTIES TONIGHT THOUGH...AS THE LATEST NAM IS A LITTLE BEEFIER WITH LIFT AND MOISTURE. FOR NOW...WILL CONTINUE WITH A SPECIAL WEATHER STATEMENT HIGHLIGHTING THE MULTIPLE IMPACTS. SNOW SHOWERS WILL GRADUALLY TAPER OFF FROM NORTHWEST TO SOUTHEAST TONIGHT...LINGERING LONGEST IN THE FAR SOUTHEAST. NORTHWEST WINDS WILL DIMINISH THROUGH THE EVENING...HOWEVER THE COMBINATION OF THE WIND AND TEMPERATURES FALLING INTO THE TEENS...WILL STILL ALLOW FOR SOME SINGLE DIGIT WIND CHILL READINGS LATE TONIGHT INTO EARLY THURSDAY MORNING. HIGH PRESSURE WILL MOVE IN FOR THURSDAY...GRADUALLY BRINGING ANY LINGERING SNOW FLURRIES TO AN END. HIGHS STILL LOOK TO NOT MAKE IT OUT OF THE 30S. .LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY) ISSUED AT 335 AM EDT WED MAR 12 2014 EXTENDED PERIOD WILL BE FAIRLY BENIGN COMPARED TO THE SHORT TERM. HOWEVER...CONFIDENCE IN MODELS IS FAIRLY LOW FROM 0Z SATURDAY ON...AS THEY ARE HAVING A VERY HARD TIME AGREEING ON UPPER LEVEL FLOW...AND AS A RESULT...SURFACE FEATURES TO IMPACT EASTERN KY. WILL RELY ON THE ALLBLEND SOLUTION FOR DAYS 4 THROUGH 7 WITH A GENERAL BLEND OF THE MODELS FOR THIS DISCUSSION. LUCKILY...0Z FRIDAY THROUGH 0Z SATURDAY IS THE ONE PERIOD WHERE SOME CONFIDENCE DOES EXISTS. THE LONGWAVE TROUGH WHICH CONTRIBUTED TO THE RETURN OF WINTER PRECIP AND TEMPS WILL BE EXITING FROM THE REGION...WITH PRESSURE HEIGHTS BUILDING THROUGHOUT THE NIGHT AND BECOMING MORE ZONAL DURING THE DAY FRIDAY. THIS TREND WILL LEAD TO SURFACE HIGH PRESSURE AND DRY...WARMING CONDITIONS AT THE SURFACE THURSDAY NIGHT THROUGH FRIDAY. WHILE HIGHS ON THURSDAY WILL ONLY BE IN THE LOW TO MID 30S...FRIDAY WILL INCREASE QUITE NICELY INTO THE MID AND UPPER 50S FOR HIGHS. MODELS ARE THEN POINTING AT A SHORTWAVE OVER THE SOUTHERN PLAINS BY 06Z SATURDAY. THIS SHORTWAVE WILL HAVE STARTED OFF AS A CLOSED LOW OVER ARIZONA AND NEW MEXICO FRIDAY...AND MOVED ONLY SLIGHTLY BY SATURDAY WHILE LOSING SUBSTANTIAL STRENGTH. MODELS ARE ALL IN AGREEMENT THAT THIS TROUGH WILL CONTINUE TO SLOWLY WEAKEN AS IT MAKES ITS WAY ENE TOWARDS THE OHIO RIVER VALLEY. HOWEVER...THIS IS ABOUT ALL THE AGREE ON. AT THE SURFACE...EXPECT THIS SHORTWAVE TO LEAD TO A SURFACE LOW PRESSURE SYSTEM...WITH SOME IMPACTS TO KENTUCKY AS IT PASSES THROUGH. HOWEVER...EVERY MODEL VARIES GREATLY ON THE EXTENT OF THE IMPACTS AND THE TIMING. THE GFS40 IS THE FASTEST SOLUTION...WITH A LINE OF PRECIP MOVING IN BETWEEN 6 AND 12Z SATURDAY...THE GEM IS ALMOST 24 HOURS LATER...AND THE ECMWF IS ANOTHER 6 HOURS AFTER THAT. AS A RESULT...LEANED ON THE ALLBLEND SOLUTION AS THE BEST COMPROMISE AT THIS POINT. MODELS CONTINUE TO DIVERGE IN SOLUTIONS FROM HERE ON OUT. DO EXPECT ANOTHER FEW SHORTWAVES TO IMPACT THE CWA THROUGH THE REST OF THE EXTENDED...BRINGING MORE CHANCES OF PRECIPITATION...BUT CONFIDENCE IS SO LOW ON WHEN AND WHERE ANYTHING WILL SET UP THAT WILL GO WITH ALLBLEND...AND THEN REDUCE ANY CHANCES THAT ARE WITHIN THE ALLBLEND DOWN TO SLIGHT SO AS NOT TO GIVE PREFERENCE OVER ONE MODEL OR ANOTHER. CHANCES WILL BE INCREASED AS MODELS START TO COME INTO BETTER AGREEMENT OVER THE NEXT FEW FORECAST CYCLES. AS FOR TEMPERATURES AND PRECIPITATION TYPE...SIMILAR PROBLEMS EXIST. HOWEVER...IF UPPER LEVEL HEIGHTS DO FALL...IT WILL NOT BE BY A SIGNIFICANT AMOUNT...SO EXPECT TEMPERATURES TO REMAIN RIGHT AROUND IF NOT SLIGHTLY BELOW NORMAL THROUGH THE REMAINDER OF THE EXTENDED. IF THIS HOLDS TRUE...PRECIP WILL FALL IN THE FORM OF RAIN DURING THE DAY AND OVERNIGHT...WITH THE EXCEPTION OF SUNDAY NIGHT...WHERE TEMPS COULD COOL OFF TO JUST BELOW FREEZING AND CAUSE A RAIN/SNOW MIX ACROSS THE AREA INSTEAD. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON) ISSUED AT 205 PM EDT WED MAR 12 2014 LOW MVFR/IFR CIGS WILL AFFECT THE AREA INTO THE EVENING BEHIND THE COLD FRONT THAT JUST PASSED THROUGH. WITH THIS FROPA...WINDS HAVE SHIFTED TO THE WEST AND NORTHWEST AT BETWEEN 15 AND 25 KTS WITH WIND GUSTS CLOSER TO 35 KTS. LINGERING RAIN SHOWERS WILL CHANGEOVER TO SNOW SHOWERS FROM NORTHWEST TO SOUTHEAST BETWEEN 20 AND 00Z. FOLLOWING THIS...THERE WILL BE A PERIOD OF SNOW SHOWERS...LASTING LONGEST IN THE NORTHEAST PARTS OF THE FORECAST AREA. DURING THIS... CIGS AND VIS WILL BE IFR OR WORSE...FOR AT TIME. CEILINGS WILL GRADUALLY IMPROVE TOWARDS DAWN FROM WEST TO EAST WITH VFR CONDITIONS POSSIBLE BY MID MORNING THURSDAY. WINDS WILL SLACKEN LATER TONIGHT FROM THE NORTHWEST AND THEN CONTINUE AT 5 TO 10 KTS FROM THE WEST THROUGH THE DAY THURSDAY. && .JKL WATCHES/WARNINGS/ADVISORIES... WIND ADVISORY UNTIL 10 PM EDT THIS EVENING FOR KYZ044-050>052- 058>060-068-069-079-080-083>088-104-106>120. && $$ UPDATE...GREIF SHORT TERM...GEOGERIAN LONG TERM...JMW AVIATION...GREIF
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
530 PM EDT WED MAR 12 2014 .SYNOPSIS... A VERY STRONG LOW PRESSURE CENTER AND ITS ASSOCIATED COLD FRONT WILL PASS THROUGH THE MID-ATLANTIC STATES BY THIS EVENING. AN UPPER LEVEL TROUGH WILL MOVE ACROSS THE AREA TONIGHT...THEN CANADIAN HIGH PRESSURE WILL BUILD THROUGH THURSDAY NIGHT AND MOVE OFF THE COAST FRIDAY. ANOTHER WEAK DISTURBANCE MOVES THROUGH TO START THE WEEKEND. FOR THE SECOND HALF OF THE WEEKEND...HIGH PRESSURE WILL BUILD OVER THE GREAT LAKES WHILE ANOTHER UPPER DISTURBANCE PASSES THROUGH THE MID-ATLANTIC. && .NEAR TERM /THROUGH THURSDAY/... SEVERE THUNDERSTORM WATCH #28 HAS BEEN ISSUED FOR COUNTIES EAST OF THE BLUE RIDGE EXCLUDING THE CENTRAL FOOTHILLS...WHERE THE NARROW LINE OF CONVECTION ALONG THE FRONT HAS ALREADY PASSED THRU. PER LATEST RADAR TRENDS AND HRRR SIM REFLECTIVITY FORECAST...EXPECT THIS LINE TO INTENSIFY A BIT OVER THE NEXT COUPLE OF HRS AS IT REACHES THE I-95 CORRIDOR AND CHESAPEAKE BAY. THE LINE SHOULD CLEAR THE CHSPK BAY BETWEEN 730 PM AND 830 PM. PREVIOUS DISCUSSION... 983/984 MB SFC LOW IS NOW IN SRN PA AND THIN CONVECTIVE LINE HAS EVOLVED FROM THAT LOW SWD ACROSS WV...FAR SWRN VA...AND ERN TN. CLOUDS ARE TRYING TO BREAK AHEAD OF THIS LINE BUT ARE HAVING TROUBLE AT THE MOMENT NORTH OF THE VA/NC BORDER. EVEN WITH THE CLOUD COVER...TEMPS AND DEWPOINTS HAVE SURGED...WITH TEMPS IN THE MID/UPPER 60S AND DEWPOINTS IN THE 50S SOUTH OF THE FRONT. AN EARLIER WIND SURGE LED TO 40-50 KNOT GUSTS IN LOUDOUN AND MONTGOMERY COUNTIES...BUT THIS APPEARS TO HAVE SINCE SUBSIDED. THE FRONT WILL PASS THROUGH THIS EVENING...USHERING IN MARKEDLY COLDER AIR. LETS GO THREAT BY THREAT. FIRST...THE STORM THREAT FOR THIS AFTERNOON. THE LINE WILL CROSS THE CWA BETWEEN 3 PM AND 8 PM. SO FAR THERE HAS BEEN LITTLE LIGHTNING IN THIS ACTIVITY AND WIND GUSTS HAVE NOT REALLY BEEN ANY MORE SIGNIFICANT THAN THE GRADIENT WIND. REGARDLESS...THIS ACTIVITY IS MOVING INTO A SLIGHTLY WARMER ENVIRONMENT AS IT GETS HERE...SO IT WILL HAVE TO BE MONITORED. AND AS WE HAVE SEEN...THE WINDS ARE STRONG ENOUGH ALREADY AS IT IS. NEXT IS THE WIND THREAT. A WIND ADVISORY STARTS AT 6 PM AND HAS BEEN EXPANDED TO INCLUDE THE ENTIRE FORECAST AREA. WINDS ARE ALREADY WIDESPREAD GUSTING TO 25 TO 35 KNOTS AND THIS WILL PICK UP EVEN FURTHER SINCE THE PRESSURE GRADIENT IS ACTUALLY STRONGER BEHIND THE FRONT. SOME OF THE GUIDANCE INDICATES WIND GUSTS EXCEEDING 50 KNOTS THIS EVENING...ESPECIALLY AT HIGHER ELEVATIONS. THEREFORE...THE POTENTIAL FOR A SHORT-LEAD-TIME UPGRADE TO HIGH WIND WARNING DOES EXIST BEHIND THE FRONT. WINDS WILL STAY QUITE GUSTY THROUGH THE MORNING HOURS ON THURSDAY AND THEN VERY GRADUALLY SUBSIDE DURING THE AFTERNOON. SHARPLY COLDER TEMPERATURES AND WIND CHILLS ARE ANOTHER THREAT. TEMPS SHOULD DROP 30-40 DEGREES IN ABOUT FOUR HOURS AS THE FRONT PASSES...WITH LOWS TONIGHT RANGING FROM THE SINGLE DIGITS IN THE HIGHLANDS...TO 20-25 EAST OF THE BLUE RIDGE. BETWEEN A LACK OF RAIN...AND PLENTY OF WIND...THERE PROBABLY WILL NOT BE MUCH IN THE WAY OF ICING PROBLEMS FOR THE MORNING COMMUTE. WIND CHILLS WILL BE NO HIGHER THAN THE SINGLE DIGITS AREAWIDE...AND BELOW ZERO IN MANY LOCATIONS IN THE HIGHLANDS AND NORTHERN MARYLAND. WIND CHILLS COULD APPROACH 20 BELOW ZERO IN SPOTS IN THE HIGHLANDS. TEMPERATURES WILL REMAIN NEAR OR BELOW FREEZING IN MOST AREAS ON THURSDAY. UPSLOPE SNOW WILL DEVELOP WEST OF THE ALLEGHENY FRONT THIS EVENING AND CONTINUE THROUGH MUCH OF THE NIGHT. CURRENT THINKING IS MAYBE A COUPLE OF INCHES OF SNOW...BUT THAT AMOUNT COULD VARY GREATLY DEPENDING ON THE LENGTH OF TIME SNOW OCCURS AND HOW QUICKLY TEMPS FALL BELOW FREEZING BEHIND THE FRONT. A WINTER WEATHER ADVISORY CANNOT BE RULED OUT FOR THESE AREAS. ELSEWHERE...SNOW CHANCES APPEAR SMALL...IF ANY. FOR DETAILS ON THE MARINE/COASTAL FLOOD/FIRE WEATHER THREATS...SEE THEIR RESPECTIVE SECTIONS OF THIS DISCUSSION. && .SHORT TERM /THURSDAY NIGHT THROUGH FRIDAY/... WINDS WILL DIMINISH THURSDAY EVENING AS HIGH PRESSURE MOVES OVERHEAD. THE LIGHTER WINDS AND A MOSTLY CLEAR SKY SHOULD ALLOW TEMPERATURES TO PLUMMET THURSDAY EVENING...WITH OVERNIGHT LOWS GENERALLY AROUND 20 EXPECTED...EXCEPT 20 TO 25 IN THE INNER CITIES. MILDER WEATHER IS EXPECTED FRIDAY AS COLD HIGH PRESSURE DEPARTS TO THE EAST AND SOUTHERLY RETURN FLOW SETS UP. HIGHS IN THE 50S TO NEAR 60 ARE EXPECTED. A COLD FRONT WILL APPROACH THE AREA FROM THE GREAT LAKES FRIDAY NIGHT INTO SATURDAY...BUT AT THIS TIME DOES NOT APPEAR TO HAVE MUCH MOISTURE WITH IT. THE BEST CHANCE OF PRECIPITATION WILL BE OVER THE POTOMAC HIGHLANDS WHERE A FEW RAIN OR SNOW SHOWERS ARE POSSIBLE. COLDER AIR LAGS BEHIND THE FRONT...SO SATURDAY SHOULD BE ANOTHER MILD DAY WITH HIGH TEMPERATURES SIMILAR TO THAT OBSERVED ON FRIDAY. && .LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/... SUNDAY WILL LIKELY BE THE NICEST DAY OF THE LONG TERM PERIOD WITH HIGH TEMPS NEAR 50 DEGREES...NEAR NORMAL FOR THIS TIME OF YEAR...AND PARTLY SUNNY SKIES. HIGH PRESSURE OVER THE GREAT LAKES WILL KEEP LIGHT WINDS OUT OF THE NORTH DURING THE DAY. THE FRONTAL BOUNDARY THAT CROSSED OUR AREA SATURDAY WILL STALL OFF OF THE EAST COAST SUNDAY NIGHT AND MODAL AGREEMENT IS VERY LOW ON WHAT WILL HAPPEN NEXT. UPPER LEVEL TROUGHING OVER THE GREAT LAKES SHOULD ENCOURAGE THE FORMATION OF A LOW PRESSURE WAVE ALONG THE STALLED BOUNDARY OVER THE GULF COAST. THIS WAVE SHOULD MOVE UP THE EAST COAST AS THE UPPER LEVEL TROUGH LIFTS THROUGH THE BEGINNING OF THE WORKWEEK. TRACK AND TIMING OF THIS COASTAL LOW IS STILL VERY UNCERTAIN...AS THERE IS VERY HIGH VARIABILITY WITHIN ENSEMBLE MEMBERS OF GLOBAL MODELS. TRACK WILL PLAY A LARGE ROLL IN PTYPE AND LOCAL IMPACTS. ASSUMING THAT LOW TRACKS UP THE COAST AND WE REMAIN IN THE COLD SECTOR OF THE STORM...WINTRY PRECIP IS A REALISTIC EXPECTATION. HAVE FORECAST HIGHS NEAR 40 AND LOWS IN THE UPPER 20S FOR NEXT WEEK WITH LOW END CHANCE POPS THROUGH THE ENTIRE BEGINNING OF THE WORKWEEK. HAVE STARTED PTYPE AS RAIN AND INCLUDED POSSIBILITY OF SNOW OVERNIGHT MONDAY TO ACCOUNT FOR UNCERTAINTY OF LOW TRACK AND DYNAMICS. && .AVIATION /22Z WEDNESDAY THROUGH MONDAY/... THIN LINE OF SHRA/POSSIBLE TSRA WILL MOVE THROUGH THE TERMINALS BETWEEN 20 UTC AND 23 UTC. RELATIVELY BRIEF VSBY/CIG RESTRICTIONS ARE LIKELY AS THIS LINE PASSES. BIG STORY FOR AVIATION WILL BE THE GUSTY AND PERSISTENT WIND. WINDS OUT OF THE SOUTH WILL SHIFT OUT OF THE WEST AND THEN NORTHWEST AS THE FRONT PASSES...AND LIKELY BECOME EVEN GUSTIER THAN THEY HAVE BEEN. WIND GUSTS OVER 40 KTS ARE LIKELY AT TIMES. WINDS WILL GRADUALLY SUBSIDE ON THURSDAY. ASIDE FROM THE CONVECTIVE LINE...VFR CIGS/VSBYS ARE EXPECTED. VFR CONDITIONS ARE EXPECTED THURSDAY NIGHT THROUGH SATURDAY...WITH THE EXCEPTION OF TERMINALS OVER THE POTOMAC HIGHLANDS WHERE SUB-VFR CONDITIONS ARE POSSIBLE IN RAIN OR SNOW SHOWERS. GUSTY NORTHWEST WINDS OF 15 TO 20 KNOTS WITH GUSTS TO 25 KNOTS ARE EXPECTED THURSDAY EVENING...BECOMING LIGHT AND VARIABLE AFTER MIDNIGHT. SOUTHERLY WINDS AROUND 10 KNOTS ARE EXPECTED FRIDAY INTO FRIDAY NIGHT WITH GUSTS TO 20 KNOTS POSSIBLE. WINDS THEN BECOME WEST AROUND 10 KNOTS SATURDAY. && .MARINE... EXPANDED THE GALE WARNING TO ALL WATERS...STARTING EARLIER AND ENDING LATER. GUSTS OVER 30 KNOTS ARE ALREADY HAPPENING AND WILL CONTINUE AND EVEN INTENSIFY AS THE FRONT PASSES. GALE-LEVEL GUSTS WILL CONTINUE THROUGH MOST OF THURSDAY...ESPECIALLY OVER THE MORE OPEN WATERS OF THE LOWER TIDAL POTOMAC AND MARYLAND CHESAPEAKE BAY. WINDS WILL GRADUALLY SUBSIDE DURING THE LATE AFTERNOON THURSDAY. SCA CONDITIONS ARE EXPECTED THURSDAY EVENING IN A GUSTY NORTHWEST FLOW. A BRIEF LULL IN WINDS IS FORECAST THROUGH FRIDAY MORNING...WITH GUSTY SOUTHERLY FLOW BRINGING ANOTHER ROUND OF SCA WINDS FRIDAY AFTERNOON AND EVENING...BEFORE WINDS SLACKEN OFF OVERNIGHT FRIDAY NIGHT INTO SATURDAY MORNING. A SMALL CRAFT ADVISORY MAY BE NECESSARY BEGINNING SUNDAY NIGHT AS A COASTAL LOW MAY MOVE NEAR THE AREA. && .FIRE WEATHER... ABUNDANTLY DRY AIR WILL ACCOMPANY THE ARCTIC AIRMASS INVADING THE AREA ON THURSDAY...WITH DEW POINTS BELOW ZERO EXPECTED. THIS WILL RESULT IN RELATIVE HUMIDITY VALUES BOTTOMING OUT AT 20 TO 25 PERCENT THURSDAY AFTERNOON...ESPECIALLY EAST OF THE BLUE RIDGE. THE DRY AND WINDY CONDITIONS MAY RESULT IN AN ENHANCED FIRE SPREAD POTENTIAL. A FIRE WEATHER WATCH HAS BEEN ISSUED FOR ALL OUR VIRGINIA COUNTIES EAST OF THE BLUE RIDGE IN COORDINATION WITH NEIGHBORING OFFICES AND FIRE OFFICIALS. THE REMAINDER OF THE AREA WILL BE FURTHER CONSIDERED FOR SPS AND POTENTIAL FIRE WEATHER HEADLINES TONIGHT OR TOMORROW. && .TIDES/COASTAL FLOODING... COASTAL FLOOD ADVISORY HAS EXPIRED. WITH THE ANNAPOLIS BUOY REMAINING JUST BELOW THRESHOLD DURING THE AFTN HIGH TIDE... COASTAL FLOODING ELSEWHERE UNLIKELY. WATER LEVELS WILL SHARPLY DECREASE FOLLOWING FRONTAL PASSAGE...AND A NEGATIVE ANOMALY OVER ONE FOOT IS LIKELY BY THURSDAY AFTERNOON. && .LWX WATCHES/WARNINGS/ADVISORIES... DC...WIND ADVISORY UNTIL 11 AM EDT THURSDAY FOR DCZ001. MD...WIND ADVISORY UNTIL 11 AM EDT THURSDAY FOR MDZ003>007-009>011- 013-014-016>018-501-502. WIND CHILL ADVISORY FROM 11 PM THIS EVENING TO NOON EDT THURSDAY FOR MDZ501-502. VA...WIND ADVISORY UNTIL 11 AM EDT THURSDAY FOR VAZ025>031-036>040- 042-050>057-501>504. WIND CHILL ADVISORY FROM 11 PM THIS EVENING TO NOON EDT THURSDAY FOR VAZ503-504. FIRE WEATHER WATCH FROM THURSDAY MORNING THROUGH THURSDAY AFTERNOON FOR VAZ036>040-042-050>057-501-502. WV...WIND ADVISORY UNTIL 11 AM EDT THURSDAY FOR WVZ050>053-055- 501>506. WIND CHILL ADVISORY FROM 11 PM THIS EVENING TO NOON EDT THURSDAY FOR WVZ501>506. MARINE...GALE WARNING UNTIL 8 PM EDT THURSDAY FOR ANZ530>534-537>543. SMALL CRAFT ADVISORY FROM 11 AM TO 8 PM EDT THURSDAY FOR ANZ535-536. GALE WARNING UNTIL 11 AM EDT THURSDAY FOR ANZ535-536. && $$ SYNOPSIS...JCE NEAR TERM...JRK/JCE SHORT TERM...DFH LONG TERM...CEB AVIATION...JCE/CEB/DFH MARINE...JCE/CEB/DFH FIRE WEATHER...JCE TIDES/COASTAL FLOODING...JRK
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
129 PM EDT WED MAR 12 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 403 AM EDT WED MAR 12 2014 THE COLD FRONT THAT SHIFTED SOUTH ACROSS UPPER MICHIGAN LATE YESTERDAY AFTERNOON AND EVENING PRODUCED SNOW SHOWERS OVER MUCH OF WESTERN AND CENTRAL UPPER MICHIGAN...WITH THE STRONGEST SHOWERS SEEN OVER NORTH CENTRAL UPPER MICHIGAN. THIS WAS DUE TO THE NORTH TO NORTHEAST WINDS PROVIDING TERRAIN ENHANCEMENT TO THE LIGHTER SNOW SHOWERS AND ENDED UP PRODUCING ABOUT AN INCH OF SNOW AT OUR OFFICE THROUGH 2AM. THE INTENSITY HAS REALLY DIMINISHED OVER THE LAST HOUR OR TWO DUE TO THE DRY AIR (ASSOCIATED WITH THE HIGH OVER NORTHWEST ONTARIO) THAT HAS BEEN SURGING SOUTH ACROSS LAKE SUPERIOR ON IR SATELLITE. WITH LIMITED BREAKS IN THE ICE...THE COLD AIR (RAP ANALYZED 900MB TEMPERATURES OF -17C) HAS ONLY BEEN ABLE TO PRODUCE A COUPLE LAKE EFFECT CLOUD STREAMERS OFF THE OPEN AREA NEAR ISLE ROYALE AND THAT IS STRETCHING TOWARDS AREAS SOUTHWEST OF THE PORCUPINE MOUNTAINS. THIS DRYING ABOVE 900MB HAS LED TO SIGNIFICANT ADJUSTMENTS TO THE GOING FORECAST. SINCE THE HIGH WILL CONTINUE TO SLIDE SOUTHEAST OVER THE AREA THROUGH THE DAY TODAY...HAVE TRENDED THE FORECAST TOWARDS A FASTER END TO THE SNOW. WOULD EXPECT THE CLOUDS AND LIGHT SNOW SHOWERS OR FLURRIES TO REMAIN THE LONGEST OVER THE NORTH CENTRAL U.P. WHERE THE NORTHEAST WINDS WILL REMAIN MOST FAVORABLE. LOOKING AT 00Z NAM/GFS SOUNDINGS THEY DO HOLD ONTO MOISTURE RIGHT BELOW THAT INVERSION INTO THE AFTERNOON FOR KSAW...BUT THE LAST SEVERAL RAP RUNS REALLY SCOUR THAT MOISTURE OUT. THUS...WILL KEEP THE TREND TOWARDS PARTLY CLOUDY SKIES BY AFTERNOON OVER THE NORTH CENTRAL AND PARTLY CLOUDY TO MOSTLY SUNNY ELSEWHERE AWAY FROM THE UPSLOPE FLOW. AS FOR THE SNOW SHOWERS...HAVE CUT THAT BACK SIGNIFICANTLY...WITH THEM MAINLY BEING CONFINED TO THE NORTH CENTRAL FOR THE NEXT FEW HOURS AND THEN QUICKLY DIMINISHING DURING THE MORNING WITH THE WINDS STARTING TO BACK MORE TO THE NORTH-NORTHWEST. WILL MONITOR CLOUD/SNOW TRENDS THROUGH DAY BREAK AND MAY NEED TO DIMINISH THEM EVEN EARLIER THAN THE GOING FORECAST. WITH THE COLD AIR ALOFT THAT IS MOVING OVER THE AREA...EXPECT THE EARLY MORNING TEMPERATURES TO CONTINUE TO SLOWLY FALL. THE 3AM OBS (RANGING FROM 9 DEGREES IN COPPER HARBOR AND 27 IN MENOMINEE) WILL LIKELY BE THE WARMEST VALUES FOR THE RESPECTIVE LOCATIONS AND ONLY HAVE HIGHS IN THE UPPER SINGLE DIGITS TO THE NORTH AND THE MID TEENS TO THE SOUTH. AM A LITTLE CONCERNED THE WARM MARCH SUN THIS AFTERNOON COULD PRODUCE HIGHS A LITTLE WARMER THAN EXPECTED AND DID ADJUST INLAND WEST AREAS UP A COUPLE DEGREES TO ACCOUNT FOR THIS. FOR SEVERAL COOP SITES OVER THE WEST THAT REPORT ON A 7AM-7AM CYCLE...DAYTIME HIGHS TODAY COULD BE NEAR OR BREAK RECORD LOW HIGHS FOR THE OBS THAT WILL BE REPORTED ON MARCH 13TH. WITH THE HIGH BEING OVER DIRECTLY OVER THE U.P. THIS EVENING AND CLEAR SKIES...EXPECT TEMPERATURES TO QUICKLY DROP OVER THE WEST AND CENTRAL INITIALLY WITH THE LIGHT WINDS. THOSE AREAS SHOULD SEE THEIR LOWS EARLIER THAN THE EAST DUE TO THE HIGH SHIFTING SOUTHEAST OF THE AREA LATE TONIGHT AND ALLOWING SOUTHERLY FLOW TO DEVELOP. IN ADDITION...MID CLOUDS WILL BE ARRIVING OVER THE WEST LATE IN RESPONSE TO INCREASING WARM AIR ADVECTION ALOFT AND COULD EVEN LEAD TO SOME LIGHT SNOW SHOWERS OVER THE WESTERN QUARTER OF LAKE SUPERIOR BEFORE 12Z. OVER THE EAST...THE LATER WEAKENING OF THE WINDS SHOULDN/T HAVE MUCH AFFECT ON THE LOWS AND EXPECT THE LONGER RADIATIONAL COOLING TIME TO ALLOW LOWS TO EASILY FALL INTO THE TEENS BELOW ZERO. WILL CONTINUE TO FOLLOW THE NH/REGIONAL CANADIAN MODEL FOR TEMPERATURES OVER THE EAST...DUE TO IT/S GREAT PERFORMANCE THIS WINTER ON THESE TYPES OF NIGHTS. DID TREND LOWS DOWN A LITTLE FOR SOME OF THE TRADITIONAL COLD SPOTS (RAWS SITES LIKE DOE LAKE AND SPINCICH LAKE)...WHICH WILL LIKELY SEE VALUES FALLING INTO THE LOWER -20S. CURRENT FORECAST HAS LOWS NEARING/BREAKING RECORDS FOR MANISTIQUE (-7 IN 1948) AND MUNISING (-10 IN 1926). .LONG TERM...(THURSDAY THROUGH TUESDAY) ISSUED AT 513 AM EDT WED MAR 12 2014 THE OVERALL PATTERN WILL CONTINUE TO BE INFLUENCED BY RIDGING OVER WRN NOAM AND THE RESULTING DOWNSTREAM TROUGH INTO THE GREAT LAKES AND NERN CONUS...KEEPING TEMPS MAINLY BELOW NORMAL. A CLIPPER SHORTWAVE AND LOW MOVING THROUGH THE REGION WILL BRING A WARMUP FRIDAY WITH A CHANCE OF SOME LIGHT PCPN BUT WILL DRAG MUCH COLDER AIR INTO THE REGION IN ITS WAKE FOR THE WEEKEND. THU...AS ARCTIC HIGH PRES SHIFTS TO THE EAST AND MID LEVEL RIDGING BUILDS TOWARD THE UPPER MS VALLEY...WAA WILL SPREAD CLOUDS THROUGH UPPER MICHIGAN. ONLY SLIGHT CHANCE POPS FOR LIGHT SNOW WERE INCLUDED GIVEN ONLY LIMITED MOISTURE AVAILABILITY AND RELATIVELY SMALL NET ISENTROPIC LIFT AS THE 850-700 MB LAYER WARMS. A LARGE SPREAD OF HIGH TEMPS IS EXPECTED WITH READINGS RANGING FROM AROUND 20 NEAR ERY TO 40 AT IWD. THU NIGHT INTO FRI...THE GEM AND ECMWF HAVE REMAINED FARTHER SOUTH WITH THE TRACK OF THE CLIPPER SHRTWV COMPARED TO THE NAM AND GFS. EVEN THOUGH THERE IS LINGERING MODEL UNCERTAINTY...THERE SHOULD BE ENOUGH 700-300 MB QVECTOR CONV WITH THIS FEATURE TO SUPPORT AT LEAST LOW END PCPN CHANCES OVER MOST OF THE CWA FRI...ESPECIALLY OVER THE NORTH HALF. ALTHOUGH THERE MAY BE ENOUGH WARM AIR IN THE WARM SECTOR TO SUPPORT SOME LIGHT RAIN...WET-BULB ZERO HEIGHTS FAVOR MAINLY SNOW. HIGHS SHOULD STILL CLIMB ABOVE NORMAL INTO THE MID AND UPPER 30S. FRI NIGHT AND SAT...THE LOW PRESSURE SYSTEM WILL DRAG A COLD FRONT THROUGH UPPER MI WITH 850 MB TEMPS FALLING TO NEAR -14C BY 12Z/SAT AND -20C BY 00Z/SUN. THE MOST FAVORABLE PERIOD FOR SNOW SHOWERS... AIDED BY HEAT/MOISTURE FLUX ACROSS SOME GAPS IN THE ICE COVER AND UPSLOPE FLOW INTO THE HIGHER TERRAIN...WILL BE BETWEEN 06Z-18Z WHEN THE GREATER 850-700 MB MOISTURE AND IS PRESENT. ANY SNOW SHOWERS STILL BE LIGHT...GENERALLY ONLY AN INCH OR TWO AT MOST. TEMPS WILL STRUGGLE TO AROUND 20 NORTH BUT MAY CLIMB TO THE UPPER 20S SOUTH. SUN-TUE...AS THE ARCTIC HIGH SETTLES INTO THE REGION SUN...HIGHS WILL REMAIN IN THE TEENS UNDER MOSTLY SUNNY SKIES AFTER MORNING LOWS AT OR JUST BELOW ZERO. MODEL DIFFERENCES ARE MUCH GREATER BY MON-TUE AS THE ECMWF KEEPS MORE TROUGHING AND COLD AIR OVER THE GREAT LAKES COMPARED TO THE GFS/GEM WHICH KEEPS MOST OF THE PCPN WITH A SHRTWV AND LOW TO THE SOUTH AND WEST OF UPPER MICHIGAN. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON) ISSUED AT 127 PM EDT WED MAR 12 2014 GUSTY NORTH WINDS AT KSAW WILL GIVE WAY TO LIGHT WINDS BY THIS EVENING. MID CLOUDS INCREASE LATE TONIGHT AT ALL THE TAF SITES AND THESE WILL GRADUALLY LOWER ON THURSDAY. LGT SNOW OR FLURRIES MAY OCCUR ON THURSDAY AT ANY OF THE TAF SITES...BUT DID NOT MENTION ATTM. NO REAL REDUCTION TO VSBY IS EXPECTED FROM ANY SNOW THAT WOULD OCCUR. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 403 AM EDT WED MAR 12 2014 COLD AIR SURGING SOUTH ACROSS LAKE SUPERIOR THIS PAST EVENING LED TO A PERIOD OF NORTHERLY GUSTS TO 25-30KTS OVER MUCH OF THE LAKE. THESE WINDS ARE EXPECTED TO QUICKLY DIMINISH TODAY AS AN AREA OF HIGH PRESSURE IN NORTHWEST ONTARIO QUICKLY SHIFTS SOUTHEAST OVER THE UPPER GREAT LAKES REGION. THIS HIGH WILL EXIT THE AREA LATE TONIGHT AND THURSDAY MORNING ALLOWING SOUTHWESTERLY WINDS TO START TO INCREASE AHEAD OF THE NEXT CLIPPER SYSTEM THAT WILL MOVE ACROSS LAKE SUPERIOR THURSDAY NIGHT AND FRIDAY MORNING. SOUTHWEST WINDS MAY INCREASE TO 15-25KTS AHEAD OF THIS LOW...THEN SHIFT TO THE NORTHWEST AT SIMILAR VALUES ON THE BACK SIDE OF THE LOW. HIGH PRESSURE WILL THEN BUILD SOUTH FROM CANADA SATURDAY AFTERNOON INTO SUNDAY AND PRODUCE WEAKENING WINDS. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...SRF LONG TERM...JLB AVIATION...JLA MARINE...SRF
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
119 PM EDT WED MAR 12 2014 .AVIATION... //DISCUSSION... STRONG NORTHERLY GRADIENT WINDS TRAILING THE SURFACE CYCLONE WILL BE THE OVERWHELMING INFLUENCE ON THE WEATHER DURING THE NEXT 6 HOURS. LIFR VSBY RESTRICTIONS OF 1/4 TO 1/2SM DUE TO BLOWING SNOW WILL TRANSITION TO IFR (1SM) AT THE START OF THE PERIOD WITH THE HEAVY SNOW BAND PUSHING EAST. THE NORTHERLY WINDS OF 30 TO 40 MPH ARE EXPECTED TO PERSIST FOR THE AFTERNOON AND EVENING HOURS BEFORE EASING WITH THE LOSS OF THE DAYTIME BOUNDARY LAYER. SUSTAINED NORTHWESTERLY WINDS OF 10 MPH WILL HOLD THROUGH THE FIRST HALF OF TONIGHT. //DTW THRESHOLD THREATS... * HIGH CONFIDENCE ON CEILING BELOW 5000 FEET TODAY. * HIGH CONFIDENCE IN SNOW AS PRECIPITATION TYPE. && .PREV DISCUSSION...ISSUED 1206 PM EDT WED MAR 12 2014 UPDATE... CURRENT SURFACE ANALYSIS DEPICTS A SURFACE CYCLONE OF 988 MB OVER WESTERN PA WHICH IS SLIGHTLY AHEAD OF PACE. IN RESPONSE...SURFACE WINDS OVER SOUTHEASTERN MICHIGAN HAVE VEERED TO THE NORTHEAST OPENING THE DOORS TO LOW LEVEL COLD AIR ADVECTION. AS OF 11 AM...THE COLD AIR HAS MADE INROADS TO ALONG AND NORTH OF THE GLACIAL RIDGE. THE INTRODUCTION OF THE RESULTANT STEEPER MIDLEVEL LAPSE RATES HAS HAD THE EXPECTED IMPACT ON SURFACE WINDS...WITH MAGNITUDES NOW OF 20 TO 35 MPH ACROSS THE BOARD. THE WINDS IN COMBINATION WITH THE SMALLER SNOWFLAKES IS CAUSING A SIGNIFICANT CONTRIBUTION TO THE REDUCED VISIBILITIES. MAIN DEFORMATION BAND IS NOW IN THE PIVOTING PHASE WITH REGARDS TO SOUTHEASTERN MICHIGAN. THE HEAVIEST SNOWBAND IS NOW IN POSITION ACROSS THE FAR SOUTHEASTERN COUNTIES...WHERE LARGER SNOWFLAKES ARE FALLING PER OBSERVED VIDEO. WIND OBSERVATIONS OUT YIP AND HIGH Z FROM KDTX SUPPORTS THAT NEAR BLIZZARD CONDITIONS ARE OCCURRING. THESE CONDITIONS ARE EXPECTED TO BE OF A SHORT DURATION OVER THE NEXT HOUR (NOT EXPECTING LESS THAN A QUARTER MILE). WILL LIKELY SEE A GOOD SNOW ACCUMULATING BURST HERE FOR FAR SOUTHEASTERN SECTIONS WHERE AN ADDITIONAL 2 TO 3 INCHES WILL BE POSSIBLE. FOR THE REMAINDER OF THE CWA...SNOW IS EXPECTED TO STRIP OUT RAPIDLY WITH PERHAPS AN ADDITIONAL 1 TO 2 INCHES SOUTH OF I 69. THIS WILL PLACE THE EVENT TOTALS IN THE 6 TO 10 INCH RANGE...(HIGHEST ALONG THE GLACIAL RIDGE SPINE AND LOWEST FROM WASHTENAW-WAYNE-EXTREME SOUTHEASTERN OAKLAND COUNTY. ONCE THE PRECIPITATION ENDS...THE NARRATIVE WILL SWITCH TO REDUCED VISIBILITIES DUE TO BLOWING SNOW THAT WILL LINGER THROUGH THE EVENING COMMUTE. PREV DISCUSSION...ISSUED 353 AM EDT WED MAR 12 2014 SHORT TERM... TODAY AND TONIGHT A HIGH IMPACT WINTER STORM SYSTEM REMAINS ON TRACK FOR THE SOUTH HALF OF SE MICHIGAN WITH THE PEAK OF THE EVENT DURING THE MORNING COMMUTE ALONG AND SOUTH OF THE I-69 CORRIDOR. THE SYSTEM WILL BRING HEAVY SNOW AND STRONG WIND OVER THE REGION DURING THE MORNING BEFORE DIMINISHING DURING EARLY AFTERNOON. HEADLINE ADJUSTMENTS CONSIST OF A WARNING UPGRADE TO LIVINGSTON, SHIAWASSEE, GENESEE, AND LAPEER. THE CHARACTER OF THIS EVENT CONTINUES TO EXHIBIT A SHARP SNOWFALL GRADIENT ON THE NORTH FLANK TO THE DEGREE THAT THE NORTHERN REACHES OF MIDLAND AND BAY COUNTIES WILL SEE JUST A DUSTING OF ACCUMULATION WHILE LOCATIONS ALONG THE I-69 CORRIDOR COULD SEE 6 INCHES IN 9 HOURS, AND LOCATIONS CLOSE TO THE OHIO BORDER COULD APPROACH 10 INCHES IF MESOSCALE ELEMENTS LINE UP JUST RIGHT. IN ADDITION, STRONG NORTHERLY WIND GUSTS COULD PRODUCE NEAR BLIZZARD CONDITIONS AT TIMES. AIDING IN THE DETERMINATION OF HEADLINE ADJUSTMENTS IS THE 00Z MODEL SUITE COMING IN WITH SOLID AGREEMENT ON THE TRACK OF THE SURFACE LOW DIRECTLY ALONG THE OHIO RIVER TO THE SOUTHWEST PENNSYLVANIA/WEST VIRGINIA BORDER BY NOON. THAT HELPS ADD CONFIDENCE TO THE LOCATION, INTENSITY, AND DURATION OF MESOSCALE FORCING FEATURES TARGETED FOR THE SLIGHT NORTHWARD EXPANSION OF THE WARNING AREA. IT ALSO REINFORCES THE IDEA OF HIGHLIGHTING THE WIND FOR HURON AND SANILAC COUNTIES GIVEN THE SHARP GRADIENT OF MEANINGFUL SNOW ACCUMULATION THERE. SURFACE OBSERVATIONS AND RADAR DEPICTION AROUND THE MIDNIGHT HOUR REVEALED THE TENDENCY FOR A RAPID CHANGE TO ALL SNOW IN REGIONS OF HIGHER PRECIPITATION RATE WITHIN THE LEADING ARM OF MID LEVEL FRONTAL FORCING. AFTER A BRIEF LULL, AND WITH ADDITIONAL LOW LEVEL COLD ADVECTION, IT IS NO SURPRISE THAT THIS REGION OF THE SYSTEM HAS LIT UP AGAIN WITH ALL SNOW AS THE PRIMARY MOISTURE SURGE ARRIVES. A CLOSED CIRCULATION AND TRUE TROWAL STRUCTURE WILL BE ABSENT FROM THE SYSTEM BUT A DEEP AND DYNAMIC DEFORMATION ZONE ON THE NW FLANK OF THE LOW WILL ENSURE A STRONG MESOSCALE RESPONSE TO FORCING AS THE SYSTEM MOVES THROUGH SE MICHIGAN. THE FIRST SIGNS OF THIS PROCESS IS THE RAPID CLOUD TOP COOLING IN IR SATELLITE IMAGERY BETWEEN MIDNIGHT AND 3 AM WITH RADAR COMPOSITE INDICATING A WIDE BAND OF HEAVY PRECIPITATION FROM NORTHERN MISSOURI INTO OUR AREA ALONG THE I-69 CORRIDOR. CONVECTIVE ELEMENTS TO THE SOUTH ARE MORE INDICATIVE OF CONVECTIVE INSTABILITY IN THE FRONTAL ZONE BELOW 850 MB, AND THIS IS WHERE LIGHTNING STRIKES SHOULD REMAIN, BUT SOME THUNDER SNOW WITHIN THE DEFORMATION AXIS IS NOT OUT OF THE QUESTION AS FAR NORTH AS METRO DETROIT. MODEL CROSS SECTIONS INDICATE IMPRESSIVE CONVECTIVE INSTABILITY IN THE 700-500 MB LAYER MATCHING UP WELL WITH THE OBSERVED BAND FILLING IN OVER THE SOUTH HALF OF SE MICHIGAN. THIS, ALONG WITH SPECIFIC HUMIDITY OF 3-4 G/KG WILL MAKE MAXIMUM USE OF A DEEP WEDGE OF FRONTOGENESIS EXCEEDING 100 UNITS. SIMILAR DEPICTION IN THE LATEST RAP OUTPUT INDICATES THE BURST OF HEAVY SNOWFALL RATES FROM HIGHER ALTITUDE AND WITH HIGHER SNOW RATIO PERSISTING THROUGH CENTRAL SECTIONS OF THE REGION WITH A PIVOT OCCURRING IN THE 12-15Z TIME PERIOD BEFORE MIGRATING SOUTHWARD AND EASTWARD DURING THE LATE MORNING. THIS IS THE SUSPECTED SOURCE OF OVERACHIEVEMENT IN SNOWFALL TOTALS ON THE NORTHERN FRINGES OF THE WARNING AREA. FARTHER SOUTH, THE GOING 6 TO 9 INCH FORECAST LOOKS SOLID AS THE MID LEVEL FRONTAL ZONE AND DEFORMATION ZONE FILL IN TO FORM ONE SOLID NW FLANK OF THE SYSTEM WITH 1-2 INCH PER HOUR PEAK RATES FOR LONGER DURATION THAN POINTS NORTH. THE SYSTEM WILL EXIT THE AREA BY MID AFTERNOON WITH TRAILING NORTHERLY FLOW CARRYING IN ANOTHER ROUND OF ARCTIC AIR. DEPENDING ON THE CLEARING TREND, BELOW ZERO MIN TEMPS ARE ON TARGET WITH FRESH SNOW COVER BY SUNRISE THURSDAY. LONG TERM...THURSDAY THROUGH TUESDAY A QUICK LOOK AT THE LONGWAVE PATTERN THROUGH THE NEXT WEEK SHOW SPLIT FLOW OVER THE WEST COAST WITH THE TROUGH STILL HOLDING ON OVER THE EASTERN CONUS. THE JET STREAM IS VERY ACTIVE/ENERGETIC...BOTH NORTHERN AND SOUTHERN STREAMS...BUT AT THIS POINT IT LOOKS LIKE THE MAJORITY OF THE PRECIP WILL TRY TO STEER CLEAR OF SOUTHERN MI. THE GOOD NEWS IS THAT WE ARE STILL GETTING SURGES OF SOUTHERLY FLOW EVERY THIRD DAY OR SO...BUT THE BAD NEWS IS THAT THESE WARM UPS INTO THE LOW 40S ARE STRUGGLING TO REACH MID MARCH AVERAGE HIGH TEMPS WHICH ARE IN THE MID 40S. TO SUM IT UP...THE MARCH ROLLER COASTER/WAVE TRAIN WILL CONTINUE FOR THE FORESEEABLE FUTURE. WILL NOW HIT ON A FEW FEATURES OF NOTE IN THE EXTENDED PERIOD. THURSDAY WILL BE A COLD DAY AS THE MID/UPPER LEVEL ARCTIC TROUGH REMAINS IN CONTROL WITH NORTHERN EXTENSION OF A HIGH PRESSURE SYSTEM AT THE SURFACE THAT SLIDE SOUTH BEHIND WEDNESDAYS BIG SYSTEM. NORTHERLY WINDS WILL BACK TO WESTERLY AS HEIGHTS BUILD THROUGH THE DAY BUT WE STILL ONLY GET TO 542DAM AT 500MB BY THURSDAY EVENING SO WE WILL NOT REALIZE THAT INCREASE AT THE SFC DURING DAYLIGHT HOURS. FRIDAY WE FIND OURSELVES IN BETWEEN THE EXITING HIGH AND A CLIPPER TRACKING EASTWARD OVER NORTHERN LAKE SUPERIOR. SW TO NE PRESSURE GRADIENT WILL SET UP GOOD SW FLOW AND WAA. LL JET AT 850MB WILL PEAK AROUND 45 KNOTS DURING THE AFTERNOON ALTHOUGH WE ONLY LOOK TO MIX UP TO AROUND 900MB. SHOULD STILL BE FAIRLY BREEZY OUT IN THE AFTERNOON WITH GUSTS REACHING 20-30 MPH. HIGHS SHOULD REACH INTO THE 40S ONCE AGAIN. THERE IS A SLIGHT CHANCE THAT A FEW RAIN/SNOW SHOWERS COULD POP UP LATE FRIDAY OR OVERNIGHT BUT THERE IS NOT MUCH MOISTURE IN THE COLUMN TO WORK WITH SO WILL CONTINUE TO LEAN TOWARD A DRY FORECAST. THIS CLIPPER WILL PULL A PAIR OF COLD FRONTS THROUGH THE REGION WHICH WILL CAUSE TEMPS TO DROP BOTH SATURDAY AND SUNDAY AS COLDER AND COLDER AIR WORKS INTO THE AREA. SAME HOLDS TRUE FOR SAT/SUN THAT MODELS ARE TRYING TO POP A FEW SHOWERS BUT DOMINATE AREA OF HIGH PRESSURE BUILDING IN FROM CANADA WILL CONTINUE TO KEEP VERY DRY AIR IN PLACE MAKING IT HARD FOR ANYTHING TO DEVELOP. EARLY NEXT WEEK IT LOOKS LIKE THE NORTHERN AND SOUTHERN STREAMS OF THE JETS WILL PHASE AGAIN PRODUCING ANOTHER STRONG LOW PRESSURE SYSTEM. ALL INDICATIONS AT THIS POINT ARE THAT THE STORM WILL DEVELOP MUCH FURTHER SOUTH AND EAST OF MI. MARINE... A STRONG LOW PRESSURE SYSTEM WILL DEEPEN AS IT TRACKS ALONG THE OHIO RIVER THROUGH THIS AFTERNOON. THE TRACK OF THE STORM PLACES THE EASTERN GREAT LAKES IN THE TIGHT NORTHEAST TO SOUTHWEST PRESSURE GRADIENT FIELD WHICH WILL RESULT IN GALE FORCE WINDS TODAY. GALE WARNINGS ARE IN EFFECT FOR LAKE HURON...LAKE ERIE AND LAKE ST CLAIR THROUGH THIS EVENING. SEE CURRENT MARINE HEADLINES FOR THE LATEST INFORMATION. A HIGH PRESSURE SYSTEM WILL THEN DROP THROUGH THE GREAT LAKES FROM CANADA ALLOWING THE WINDS TO SUBSIDE. YET ANOTHER LOW PRESSURE SYSTEM WILL MOVE ACROSS NORTHERN LAKE SUPERIOR ON FRIDAY BRING A RETURN OF MODERATE SOUTHWEST FLOW AND MILDER AIR. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...WINTER STORM WARNING...MIZ060-MIZ061-MIZ062-MIZ063-MIZ068-MIZ069- MIZ070-MIZ075-MIZ076-MIZ082-MIZ083...UNTIL 3 PM WEDNESDAY. WINTER WEATHER ADVISORY...MIZ053-MIZ054-MIZ055...UNTIL 3 PM WEDNESDAY. WIND ADVISORY...MIZ049-MIZ055...UNTIL 6 PM WEDNESDAY. LAKE HURON... GALE WARNING...LHZ363-LHZ421-LHZ422-LHZ441-LHZ442-LHZ443-LHZ462- LHZ463-LHZ464...UNTIL 8 PM WEDNESDAY. LAKE ST CLAIR... GALE WARNING...UNTIL 8 PM WEDNESDAY. MI WATERS OF LAKE ERIE... GALE WARNING...UNTIL 8 PM WEDNESDAY. && $$ AVIATION.....CB UPDATE.......CB SHORT TERM...BT LONG TERM....DRK MARINE.......DRK YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
1206 PM EDT WED MAR 12 2014 .UPDATE... CURRENT SURFACE ANALYSIS DEPICTS A SURFACE CYCLONE OF 988 MB OVER WESTERN PA WHICH IS SLIGHTLY AHEAD OF PACE. IN RESPONSE...SURFACE WINDS OVER SOUTHEASTERN MICHIGAN HAVE VEERED TO THE NORTHEAST OPENING THE DOORS TO LOW LEVEL COLD AIR ADVECTION. AS OF 11 AM...THE COLD AIR HAS MADE INROADS TO ALONG AND NORTH OF THE GLACIAL RIDGE. THE INTRODUCTION OF THE RESULTANT STEEPER MIDLEVEL LAPSE RATES HAS HAD THE EXPECTED IMPACT ON SURFACE WINDS...WITH MAGNITUDES NOW OF 20 TO 35 MPH ACROSS THE BOARD. THE WINDS IN COMBINATION WITH THE SMALLER SNOWFLAKES IS CAUSING A SIGNIFICANT CONTRIBUTION TO THE REDUCED VISIBILITIES. MAIN DEFORMATION BAND IS NOW IN THE PIVOTING PHASE WITH REGARDS TO SOUTHEASTERN MICHIGAN. THE HEAVIEST SNOWBAND IS NOW IN POSITION ACROSS THE FAR SOUTHEASTERN COUNTIES...WHERE LARGER SNOWFLAKES ARE FALLING PER OBSERVED VIDEO. WIND OBSERVATIONS OUT YIP AND HIGH Z FROM KDTX SUPPORTS THAT NEAR BLIZZARD CONDITIONS ARE OCCURRING. THESE CONDITIONS ARE EXPECTED TO BE OF A SHORT DURATION OVER THE NEXT HOUR (NOT EXPECTING LESS THAN A QUARTER MILE). WILL LIKELY SEE A GOOD SNOW ACCUMULATING BURST HERE FOR FAR SOUTHEASTERN SECTIONS WHERE AN ADDITIONAL 2 TO 3 INCHES WILL BE POSSIBLE. FOR THE REMAINDER OF THE CWA...SNOW IS EXPECTED TO STRIP OUT RAPIDLY WITH PERHAPS AN ADDITIONAL 1 TO 2 INCHES SOUTH OF I 69. THIS WILL PLACE THE EVENT TOTALS IN THE 6 TO 10 INCH RANGE...(HIGHEST ALONG THE GLACIAL RIDGE SPINE AND LOWEST FROM WASHTENAW-WAYNE-EXTREME SOUTHEASTERN OAKLAND COUNTY. ONCE THE PRECIPITATION ENDS...THE NARRATIVE WILL SWITCH TO REDUCED VISIBILITIES DUE TO BLOWING SNOW THAT WILL LINGER THROUGH THE EVENING COMMUTE. && .AVIATION...ISSUED 727 AM EDT WED MAR 12 2014 //DISCUSSION... VLIFR/LIFR RESTRICTION IN MODERATE TO HEAVY SNOW WILL PERSIST FOR THE BULK OF THE MORNING FROM FNT SOUTHWARD THROUGH THE DTW CORRIDOR. ADD TO THAT A NORTH WIND GUSTING UP AROUND 30 KNOTS TO COMPLICATE CONDITIONS FOR AVIATION OPERATIONS BOTH ON THE GROUND AND IN THE AIR. MBS WILL WAVER BETWEEN IFR AND MVFR AND THESE CONDITIONS WILL SPREAD SOUTHWARD OVER THE REST OF THE SITES AS AN IMPROVEMENT DURING LATE MORNING AND EARLY AFTERNOON AS THE STRONG WINTER STORM SYSTEM EXITS THE AREA. A NEW SURGE OF ARCTIC AIR WILL FOSTER A CLEARING TREND DURING THE EVENING WITH CLEAR AND COLD CONDITIONS IN PLACE AFTER MIDNIGHT THROUGH SUNRISE THURSDAY. FOR DTW... NEAR ZERO VISIBILITY AND SNOWFALL RATES OF 1-2 INCHES PER HOUR WILL PERSIST THROUGH MID MORNING RESULTING IN TOTAL ACCUMULATION CLOSER TO THE 9 INCH END OF THE 6-9 INCH RANGE OF THE FORECAST. IMPROVEMENT WILL THEN BE GRADUAL THROUGH IFR TO MVFR IN BLOWING SNOW BY EARLY AFTERNOON. THIS WILL BE DUE TO NORTH WIND GUSTING NEAR 35 KNOTS AT TIMES UNTIL CLOSE TO SUNSET. //DTW THRESHOLD THREATS... * MODERATE CONFIDENCE IN 1/4SM VISIBILITY AND 200FT CEILING. * HIGH CONFIDENCE ON CEILING BELOW 5000 FEET TODAY. * HIGH CONFIDENCE IN SNOW AS PRECIPITATION TYPE. && .PREV DISCUSSION...ISSUED 353 AM EDT WED MAR 12 2014 SHORT TERM... TODAY AND TONIGHT A HIGH IMPACT WINTER STORM SYSTEM REMAINS ON TRACK FOR THE SOUTH HALF OF SE MICHIGAN WITH THE PEAK OF THE EVENT DURING THE MORNING COMMUTE ALONG AND SOUTH OF THE I-69 CORRIDOR. THE SYSTEM WILL BRING HEAVY SNOW AND STRONG WIND OVER THE REGION DURING THE MORNING BEFORE DIMINISHING DURING EARLY AFTERNOON. HEADLINE ADJUSTMENTS CONSIST OF A WARNING UPGRADE TO LIVINGSTON, SHIAWASSEE, GENESEE, AND LAPEER. THE CHARACTER OF THIS EVENT CONTINUES TO EXHIBIT A SHARP SNOWFALL GRADIENT ON THE NORTH FLANK TO THE DEGREE THAT THE NORTHERN REACHES OF MIDLAND AND BAY COUNTIES WILL SEE JUST A DUSTING OF ACCUMULATION WHILE LOCATIONS ALONG THE I-69 CORRIDOR COULD SEE 6 INCHES IN 9 HOURS, AND LOCATIONS CLOSE TO THE OHIO BORDER COULD APPROACH 10 INCHES IF MESOSCALE ELEMENTS LINE UP JUST RIGHT. IN ADDITION, STRONG NORTHERLY WIND GUSTS COULD PRODUCE NEAR BLIZZARD CONDITIONS AT TIMES. AIDING IN THE DETERMINATION OF HEADLINE ADJUSTMENTS IS THE 00Z MODEL SUITE COMING IN WITH SOLID AGREEMENT ON THE TRACK OF THE SURFACE LOW DIRECTLY ALONG THE OHIO RIVER TO THE SOUTHWEST PENNSYLVANIA/WEST VIRGINIA BORDER BY NOON. THAT HELPS ADD CONFIDENCE TO THE LOCATION, INTENSITY, AND DURATION OF MESOSCALE FORCING FEATURES TARGETED FOR THE SLIGHT NORTHWARD EXPANSION OF THE WARNING AREA. IT ALSO REINFORCES THE IDEA OF HIGHLIGHTING THE WIND FOR HURON AND SANILAC COUNTIES GIVEN THE SHARP GRADIENT OF MEANINGFUL SNOW ACCUMULATION THERE. SURFACE OBSERVATIONS AND RADAR DEPICTION AROUND THE MIDNIGHT HOUR REVEALED THE TENDENCY FOR A RAPID CHANGE TO ALL SNOW IN REGIONS OF HIGHER PRECIPITATION RATE WITHIN THE LEADING ARM OF MID LEVEL FRONTAL FORCING. AFTER A BRIEF LULL, AND WITH ADDITIONAL LOW LEVEL COLD ADVECTION, IT IS NO SURPRISE THAT THIS REGION OF THE SYSTEM HAS LIT UP AGAIN WITH ALL SNOW AS THE PRIMARY MOISTURE SURGE ARRIVES. A CLOSED CIRCULATION AND TRUE TROWAL STRUCTURE WILL BE ABSENT FROM THE SYSTEM BUT A DEEP AND DYNAMIC DEFORMATION ZONE ON THE NW FLANK OF THE LOW WILL ENSURE A STRONG MESOSCALE RESPONSE TO FORCING AS THE SYSTEM MOVES THROUGH SE MICHIGAN. THE FIRST SIGNS OF THIS PROCESS IS THE RAPID CLOUD TOP COOLING IN IR SATELLITE IMAGERY BETWEEN MIDNIGHT AND 3 AM WITH RADAR COMPOSITE INDICATING A WIDE BAND OF HEAVY PRECIPITATION FROM NORTHERN MISSOURI INTO OUR AREA ALONG THE I-69 CORRIDOR. CONVECTIVE ELEMENTS TO THE SOUTH ARE MORE INDICATIVE OF CONVECTIVE INSTABILITY IN THE FRONTAL ZONE BELOW 850 MB, AND THIS IS WHERE LIGHTNING STRIKES SHOULD REMAIN, BUT SOME THUNDER SNOW WITHIN THE DEFORMATION AXIS IS NOT OUT OF THE QUESTION AS FAR NORTH AS METRO DETROIT. MODEL CROSS SECTIONS INDICATE IMPRESSIVE CONVECTIVE INSTABILITY IN THE 700-500 MB LAYER MATCHING UP WELL WITH THE OBSERVED BAND FILLING IN OVER THE SOUTH HALF OF SE MICHIGAN. THIS, ALONG WITH SPECIFIC HUMIDITY OF 3-4 G/KG WILL MAKE MAXIMUM USE OF A DEEP WEDGE OF FRONTOGENESIS EXCEEDING 100 UNITS. SIMILAR DEPICTION IN THE LATEST RAP OUTPUT INDICATES THE BURST OF HEAVY SNOWFALL RATES FROM HIGHER ALTITUDE AND WITH HIGHER SNOW RATIO PERSISTING THROUGH CENTRAL SECTIONS OF THE REGION WITH A PIVOT OCCURRING IN THE 12-15Z TIME PERIOD BEFORE MIGRATING SOUTHWARD AND EASTWARD DURING THE LATE MORNING. THIS IS THE SUSPECTED SOURCE OF OVERACHIEVEMENT IN SNOWFALL TOTALS ON THE NORTHERN FRINGES OF THE WARNING AREA. FARTHER SOUTH, THE GOING 6 TO 9 INCH FORECAST LOOKS SOLID AS THE MID LEVEL FRONTAL ZONE AND DEFORMATION ZONE FILL IN TO FORM ONE SOLID NW FLANK OF THE SYSTEM WITH 1-2 INCH PER HOUR PEAK RATES FOR LONGER DURATION THAN POINTS NORTH. THE SYSTEM WILL EXIT THE AREA BY MID AFTERNOON WITH TRAILING NORTHERLY FLOW CARRYING IN ANOTHER ROUND OF ARCTIC AIR. DEPENDING ON THE CLEARING TREND, BELOW ZERO MIN TEMPS ARE ON TARGET WITH FRESH SNOW COVER BY SUNRISE THURSDAY. LONG TERM...THURSDAY THROUGH TUESDAY A QUICK LOOK AT THE LONGWAVE PATTERN THROUGH THE NEXT WEEK SHOW SPLIT FLOW OVER THE WEST COAST WITH THE TROUGH STILL HOLDING ON OVER THE EASTERN CONUS. THE JET STREAM IS VERY ACTIVE/ENERGETIC...BOTH NORTHERN AND SOUTHERN STREAMS...BUT AT THIS POINT IT LOOKS LIKE THE MAJORITY OF THE PRECIP WILL TRY TO STEER CLEAR OF SOUTHERN MI. THE GOOD NEWS IS THAT WE ARE STILL GETTING SURGES OF SOUTHERLY FLOW EVERY THIRD DAY OR SO...BUT THE BAD NEWS IS THAT THESE WARM UPS INTO THE LOW 40S ARE STRUGGLING TO REACH MID MARCH AVERAGE HIGH TEMPS WHICH ARE IN THE MID 40S. TO SUM IT UP...THE MARCH ROLLER COASTER/WAVE TRAIN WILL CONTINUE FOR THE FORESEEABLE FUTURE. WILL NOW HIT ON A FEW FEATURES OF NOTE IN THE EXTENDED PERIOD. THURSDAY WILL BE A COLD DAY AS THE MID/UPPER LEVEL ARCTIC TROUGH REMAINS IN CONTROL WITH NORTHERN EXTENSION OF A HIGH PRESSURE SYSTEM AT THE SURFACE THAT SLIDE SOUTH BEHIND WEDNESDAYS BIG SYSTEM. NORTHERLY WINDS WILL BACK TO WESTERLY AS HEIGHTS BUILD THROUGH THE DAY BUT WE STILL ONLY GET TO 542DAM AT 500MB BY THURSDAY EVENING SO WE WILL NOT REALIZE THAT INCREASE AT THE SFC DURING DAYLIGHT HOURS. FRIDAY WE FIND OURSELVES IN BETWEEN THE EXITING HIGH AND A CLIPPER TRACKING EASTWARD OVER NORTHERN LAKE SUPERIOR. SW TO NE PRESSURE GRADIENT WILL SET UP GOOD SW FLOW AND WAA. LL JET AT 850MB WILL PEAK AROUND 45 KNOTS DURING THE AFTERNOON ALTHOUGH WE ONLY LOOK TO MIX UP TO AROUND 900MB. SHOULD STILL BE FAIRLY BREEZY OUT IN THE AFTERNOON WITH GUSTS REACHING 20-30 MPH. HIGHS SHOULD REACH INTO THE 40S ONCE AGAIN. THERE IS A SLIGHT CHANCE THAT A FEW RAIN/SNOW SHOWERS COULD POP UP LATE FRIDAY OR OVERNIGHT BUT THERE IS NOT MUCH MOISTURE IN THE COLUMN TO WORK WITH SO WILL CONTINUE TO LEAN TOWARD A DRY FORECAST. THIS CLIPPER WILL PULL A PAIR OF COLD FRONTS THROUGH THE REGION WHICH WILL CAUSE TEMPS TO DROP BOTH SATURDAY AND SUNDAY AS COLDER AND COLDER AIR WORKS INTO THE AREA. SAME HOLDS TRUE FOR SAT/SUN THAT MODELS ARE TRYING TO POP A FEW SHOWERS BUT DOMINATE AREA OF HIGH PRESSURE BUILDING IN FROM CANADA WILL CONTINUE TO KEEP VERY DRY AIR IN PLACE MAKING IT HARD FOR ANYTHING TO DEVELOP. EARLY NEXT WEEK IT LOOKS LIKE THE NORTHERN AND SOUTHERN STREAMS OF THE JETS WILL PHASE AGAIN PRODUCING ANOTHER STRONG LOW PRESSURE SYSTEM. ALL INDICATIONS AT THIS POINT ARE THAT THE STORM WILL DEVELOP MUCH FURTHER SOUTH AND EAST OF MI. MARINE... A STRONG LOW PRESSURE SYSTEM WILL DEEPEN AS IT TRACKS ALONG THE OHIO RIVER THROUGH THIS AFTERNOON. THE TRACK OF THE STORM PLACES THE EASTERN GREAT LAKES IN THE TIGHT NORTHEAST TO SOUTHWEST PRESSURE GRADIENT FIELD WHICH WILL RESULT IN GALE FORCE WINDS TODAY. GALE WARNINGS ARE IN EFFECT FOR LAKE HURON...LAKE ERIE AND LAKE ST CLAIR THROUGH THIS EVENING. SEE CURRENT MARINE HEADLINES FOR THE LATEST INFORMATION. A HIGH PRESSURE SYSTEM WILL THEN DROP THROUGH THE GREAT LAKES FROM CANADA ALLOWING THE WINDS TO SUBSIDE. YET ANOTHER LOW PRESSURE SYSTEM WILL MOVE ACROSS NORTHERN LAKE SUPERIOR ON FRIDAY BRING A RETURN OF MODERATE SOUTHWEST FLOW AND MILDER AIR. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...WINTER STORM WARNING...MIZ060-MIZ061-MIZ062-MIZ063-MIZ068-MIZ069- MIZ070-MIZ075-MIZ076-MIZ082-MIZ083...UNTIL 3 PM WEDNESDAY. WINTER WEATHER ADVISORY...MIZ053-MIZ054-MIZ055...UNTIL 3 PM WEDNESDAY. WIND ADVISORY...MIZ049-MIZ055...UNTIL 6 PM WEDNESDAY. LAKE HURON... GALE WARNING...LHZ363-LHZ421-LHZ422-LHZ441-LHZ442-LHZ443-LHZ462- LHZ463-LHZ464...UNTIL 8 PM WEDNESDAY. LAKE ST CLAIR... GALE WARNING...UNTIL 8 PM WEDNESDAY. MI WATERS OF LAKE ERIE... GALE WARNING...UNTIL 8 PM WEDNESDAY. && $$ UPDATE.......CB AVIATION.....BT SHORT TERM...BT LONG TERM....DRK MARINE.......DRK YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS RALEIGH NC
145 PM EDT WED MAR 12 2014 .SYNOPSIS...A DEEPENING AREA OF LOW PRESSURE OVER THE OHIO VALLEY WILL TRACK EAST-NORTHEASTWARD THROUGH THE MIDDLE ATLANTIC STATES TODAY...WITH ATTENDANT TRAILING COLD FRONT CROSSING CENTRAL NC THIS EVENING. HIGH PRESSURE WILL BUILD INTO THE AREA FOR THE REMAINDER OF THE WEEK. && .NEAR TERM /THROUGH TONIGHT/... AS OF 1030 AM WEDNESDAY... ...A WIND ADVISORY IS IN EFFECT FOR ALL OF CENTRAL NC FOR LATE THIS AFTERNOON THROUGH MIDNIGHT ... THINKING HAS NOT CHANGED MUCH REGARDING CONVECTIVE EVOLUTION AND STRONG WINDS THIS AFTERNOON AND EVENING. LIGHT PRECIP ASSOCIATED WITH A WEAKENING SOUTHERN STREAM WAVE LIGHTING ACROSS THE AREA IS MOVING OFF TO THE NORTHEAST AND WILL FOR THE MOST PART BE OUT OF THE CWA BY JUST AFTER NOON...LEAVING A PERIOD OF NO PRECIP AND POTENTIAL FOR SOME CLEARING/ADDITIONAL HEATING. REGIONAL VIS IMAGERY SHOWS WIDESPREAD CLOUD COVER UPSTREAM...THE WINDOW FOR BREAKS IN CLOUDS IS SHORT BEFORE THE STRONG COLD FRONT SWEEPS ACROSS THE AREA BETWEEN ROUGHLY 4PM AND 11PM. STRONG SOUTHWESTERLY PREFRONTAL WINDS AND 850MB TEMPS OF 10-12C SUPPORT HIGHS IN THE LOWER 70S WEST AND UPPER 70S EAST ONCE PRECIP MOVES OUT OF THE AREA. HAVE MADE SOME MINOR ADJUSTMENTS ACROSS THE NORTH AND NORTHWEST WHERE HEATING WILL BE SHORTEST. THE BIGGEST QUESTION REGARDING CONVECTION ALONG THE COLD FRONT IS DESTABILIZATION...WHICH APPEARS WILL BE SHALLOW AND CONFINED TO IMMEDIATELY ALONG AND AHEAD OF THE FRONT. THE LATEST RAP SHOWS MAYBE 200-400 J/KG OF SBCAPE AT BEST FROM CHARLOTTE TO ROXBORO AND DWINDLING WITH EASTWARD EXTENT. UNIDIRECTIONAL EFFECTIVE SHEAR WOULD SUPPORT A BROKEN LINE OF SHOWERS AND LOW-TOPPED STORMS...WITH BETTER COVERAGE CLOSER TO THE VIRGINIA BORDER WHERE FORCING AND MOISTURE ARE A LITTLE DEEPER. THE BIGGEST CONCERN TODAY WILL BE WINDS AHEAD OF AND BEHIND THE FRONT. INCREASED MIXING THIS AFTERNOON MAY ALLOW SOME OF THE 35- 40KT WIND BETWEEN 925MB AND 850MB TO REACH THE SURFACE...ESPECIALLY WITHIN SHOWERS/STORMS ALONG THE FRONT. THE STRONGEST WINDS WILL COME BEHIND THE FRONT WITH 10-12MB PRESSURE RISES (6HR) ASSOCIATED WITH THE DEEPENING 980MB LOW OVER THE MID-ATLANTIC. THERE IS SOME INHERENT UNCERTAINTY REGARDING NOCTURNAL STABILIZATION LIMITING WINDS...BUT THE STRENGTHENING PRESSURE GRADIENT AND SUBSIDENCE SHOULD AID IN GETTING 40-45KT DOWN TO THE SURFACE IN WHAT WILL BE A MOSTLY WELL-MIXED BOUNDARY LAYER. THUS THE WIND ADVISORY APPEARS TO BE WELL TIMED. LOWS TONIGHT WILL RANGE FROM THE MID-UPPER 20 NW TO LOWER-MID 30S SE. && .SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... AS OF 300 AM WEDNESDAY... AFTER SEVERAL DAYS OF SPRING-LIKE TEMPS...DEEP UPPER TROUGHING OVER THE EAST COAST ON THURSDAY WILL LEAD TO AN ABRUPT CHANGE BACK TO WINTER-LIKE TEMPS...AS HIGHS WILL ONLY BE IN THE 40S...A GOOD 15-20 DEGREES BELOW NORMAL. IN ADDITION...A STRONG GRADIENT BETWEEN THE DEPARTING SURFACE LOW AND THE HIGH BUILDING IN WILL RESULT IN BREEZY CONDITIONS...MAKING IT FEEL EVEN COLDER. THESE BREEZY WINDS...IN ADDITION TO DEWPOINTS IN THE SINGLE DIGITS RESULTING IN RELATIVE HUMIDITY VALUES IN THE TEENS...MAY CAUSE SOME FIRE WEATHER CONCERNS. CONTINUED COORDINATION WILL TAKE PLACE WITH THE FOREST SERVICE LATER THIS MORNING REGARDING THE NEED FOR ANY STATEMENTS. WINDS WILL RELAX THURSDAY NIGHT AS HIGH PRESSURE MOVES OVERHEAD AND WITH CLEAR SKIES...OVERNIGHT LOWS WILL FALL INTO THE MID 20S. THESE WELL BELOW NORMAL TEMPS WILL BE SHORT LIVED THOUGH AS WEAK SHORTWAVE RIDGING BUILDS EAST OVER THE AREA AND THE SURFACE HIGH SLIPS OFFSHORE (SETTING UP RETURN FLOW) ON FRIDAY. ALL OF THIS WILL RESULT IN TEMPS MODERATING INTO THE MID/UPPER 50S...WITH OVERNIGHT LOWS IN THE UPPER 30S TO LOWER 40S. && .LONG TERM /SATURDAY THROUGH TUESDAY/... AS OF 300 AM WEDNESDAY... A NORTHERN STREAM SHORT WAVE TROUGH WILL MOVE ACROSS THE GREAT LAKES AND INTO THE NEW ENGLAND AREA SATURDAY INTO SUNDAY...PROPELLING A COLD FRONT THROUGH OUR AREA LATE SATURDAY NIGHT INTO EARLY SUNDAY MORNING. HOWEVER...THERE CONTINUES TO BE DISAGREEMENT AMONG THE MODELS ON OUR PRECIP CHANCES. THE GFS CONTINUES TO BE THE WETTER MODEL AS IT SHOWS SOME SOUTHERN STREAM ENERGY ALSO TRANSLATING EAST DURING THIS TIME FRAME. THE ECMWF STILL IS VIRTUALLY DRY AS THE SOUTHERN STREAM ENERGY DOES NOT KICK EAST AS FAST. WILL MAINTAIN THE CURRENT FORECAST THINKING UNTIL MODELS COME INTO BETTER AGREEMENT. THEREFORE...WILL HOLD PRECIP CHANCES DOWN...WITH ONLY AN INCREASE IN CLOUD COVER. CONTINUED LOW LEVEL SOUTHERLY FLOW WILL RESULT IN MORE AIR MASS MODIFICATION...WITH HIGHS EXPECTED TO RISE INTO THE MID 60S ON SATURDAY. BRIEF NORTHERLY WINDS BEHIND THE FRONT EARLY ON SUNDAY SHOULD RESULT IN SLIGHTLY LOWER TEMPS...GENERALLY MORE IN THE WAY OF UPPER 50S TO LOWER 60S. CONFIDENCE DECREASES EVEN FURTHER FOR VERY END OF THE WEEKEND AND INTO EARLY NEXT WEEK...BUT THE GENERAL CONSENSUS IS THAT ANOTHER NORTHERN STREAM TROUGH WILL DIG INTO THE SOUTHEAST...WITH YET ANOTHER COASTAL LOW IMPACTING THE REGION AS SOUTHERN STREAM ENERGY MOVES EAST. GIVEN THE HANDLING OF THE SOUTHERN STREAM ENERGY EARLIER IN THE WEEKEND (SEE ABOVE PARAGRAPH)...IT IS NOT SURPRISING THAT THERE CONTINUES TO BE LARGE MODEL SPREAD. THE GFS IS NOT AS DEEP WITH THE NORTHERN STREAM TROUGH AND IS STILL INDICATING MUCH LESS PRECIP FOR CENTRAL NC SUNDAY INTO MONDAY. THE ECMWF SHOWS THE SOUTHERN STREAM ENERGY FINALLY KICKING EAST AND INDICATES A DEEPER TROUGH DIGGING ACROSS THE SOUTHEAST. THE RESULTANT SURFACE LOW TRACKS ACROSS THE SOUTHEAST AND EVENTUALLY OFF THE CAROLINA COAST LATE SUNDAY INTO MONDAY. WILL LEAN MORE TOWARDS THE ECMWF AS IT HAS BEEN THE MORE CONSISTENT MODEL (PER WPC) AND THEREFORE WILL SHOW INCREASING PRECIP CHANCES SUNDAY...WITH HIGHEST POPS CENTERED ON THE SUNDAY NIGHT/MONDAY TIME FRAME. THERE IS STILL A LOT TO BE IRONED OUT...GIVEN THIS IS DAYS 5/6...BUT IF THE ECMWF VERIFIES...IT COULD BE ANOTHER GOOD RAIN EVENT FOR CENTRAL NC. IN ADDITION...THERE WOULD BE A POSSIBILITY OF SOME WINTRY PRECIP (MOST LIKELY A CHANGEOVER TO SNOW AT THE TAIL END)...BUT GIVEN THE TIME OF YEAR AND THE NOT SO FAVORABLE POSITION/STRENGTH OF THE HIGH...WILL MAINTAIN AN ALL LIQUID FORECAST FOR NOW. TEMPS WILL BE NEAR NORMAL FOR MOST OF THE WEEKEND BEFORE FALLING BACK TO BELOW NORMAL EARLY NEXT WEEK. && .AVIATION /18Z WEDNESDAY THROUGH MONDAY/... AS OF 145 PM WEDNESDAY... IFR CEILINGS AT KGSO/KINT AND MVFR ELSEWHERE WILL SCATTER OUT THIS AFTERNOON BEFORE A VERY STRONG COLD FRONT SWEEPS ACROSS THE AREA BETWEEN 21Z AND 03Z. AHEAD OF THE FRONT..WINDS ARE FROM THE SOUTHWEST IN THE 15-20KT RANGE...GUSTING TO NEAR 30KT FROM KFAY TO KRWI. A LINE OF SHOWERS AND STORMS WILL ACCOMPANY THE COLD FRONT...WITH A STRONG WIND SHIFT TO NORTHWESTERLY AND THE POTENTIAL FOR GUSTS TO AROUND 40KT. THIS WILL CREATE A STRONG CROSSWIND FOR AT MOST TERMINALS FOR SEVERAL HOURS THIS EVENING AND OVERNIGHT. STRONG NORTHWESTERLY WINDS WILL CONTINUE ON THURSDAY...THOUGH WEAKENING FROM WEST TO EAST DURING THE AFTERNOON. VFR CONDITIONS WILL PREVAIL. LOOKING AHEAD: EXPECT PREDOMINATELY VFR CONDITIONS THROUGH SATURDAY. THERE IS A SMALL CHANCE OF LOW LEVEL WIND SHEAR LATER FRIDAY NIGHT. THE NEXT STORM COULD IMPACT THE AREA AS EARLY AS SUNDAY AND INTO EARLY NEXT WEEK. && .RAH WATCHES/WARNINGS/ADVISORIES... WIND ADVISORY FROM 3 PM THIS AFTERNOON TO MIDNIGHT EDT TONIGHT FOR NCZ007>011-021>028-038>043-073>078-083>086-088-089.. && $$ SYNOPSIS...MWS NEAR TERM...CBL/SMITH SHORT TERM...KRD LONG TERM...KRD AVIATION...SMITH
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
252 PM EDT WED MAR 12 2014 .SYNOPSIS... COOL HIGH PRESSURE WILL BUILD IN TONIGHT AS A COLD FRONT PUSHES OFF TO THE EAST. THE AIRMASS WILL SLOWLY MODERATE WARMER INTO SATURDAY...BEFORE A BROAD AND COLDER UPPER LEVEL TROF BUILDS IN SUNDAY THROUGH MONDAY. && .NEAR TERM /THROUGH THURSDAY/... AS OF 130 PM EDT...A LINE OF SHOWERS IS DEVELOPING AS EXPECTED OVER ERN TN. CUT BACK SHOWER ACTIVITY CONSIDERABLY AHEAD OF THE LINE OVER THE WESTERN CAROLINAS AND NE GA THIS AFTN...BUT HAVE STILL MAINTAINED LIKELY POPS ALONG THE PROBABLE MCS TRACK WHICH WILL PRIMARILY BE ACROSS NORTH CAROLINA. AS OF 1110 AM...LOW CLOUDS ARE HOLDING ON A LITTLE LONGER THAN EXPECTED OVER THE FOOTHILLS AND PIEDMONT OF THE WRN CAROLINAS AND NE GA THIS MORNING. AND THE LATEST NAM HAS COME IN WITH IT/S GREATEST INSTABILITY JUST A LITTLE EAST OF THE FORECAST AREA AROUND 21 UTC THIS AFTN. THERE IS STILL A LINE FINE OVER ERN TN WHICH REPRESENTS THE SFC COLD FRONT. CONVECTION IS SLOWLY STRENGTHENING ALONG THE NRN PORTION OF THE LINE WHERE THERE IS GREATER FORCING...BUT THE SOUTHERN END SHOULDN/T DEVELOP INTO DEEP CONVECTION UNTIL IT GETS EAST OF THE MOUNTAINS. THE THINKING NOW IS THAT IT WILL STEADILY STRENGTHEN ONCE EAST OF THE MOUNTAINS...BUT THAT THE GREATEST SEVERE POTENTIAL WILL BE A LITTLE EAST OF THE FORECAST AREA. STILL...THE I77 CORRIDOR IS THE AREA MOST UNDER THE GUN THIS AFTN IN OUR FA. ALSO...WINDS IN THE BNDRY LAYER JUST BEHIND THE LINE ARE QUITE STRONG...AND EVEN A RELATIVELY WEAK LINE OF SHOWERS HAS THE POTENTIAL TO PRODUCE DAMAGING WINDS. OVER THE UPSTATE AND NE GA THE ATMOSPHERE LOOKS MORE CAPPED...THOUGH DEWPOINTS WILL BE A LITTLE HIGHER. OVERALL...THE HRRR TREND OF THE LINE OF CONVECTION NOT DEVELOPING VERY FAR INTO THE UPSTATE LOOKS GOOD AND HAS BEEN REFLECTED IN THE GRIDS. BUT EVEN HERE 40 KT GRADIENT WIND GUSTS ARE POSSIBLE AND THE WIND ADVISORY STILL LOOKS VALID. AS OF 630 AM...I WILL UPDATE THE FORECAST WITH THE RECENT OBSERVATIONS ACROSS THE FORECAST AREA. IN ADDITION...I WILL INCREASE POPS EARLY THIS MORNING...BASED OFF OF THE RECENT RADAR DATA. IN ADDITION...I WILL ADD TIMING AND PLACEMENT DETAILS FOR A LINE OF TSRA TO SWEEP ACROSS THE NRN I-77 CORRIDOR THIS AFTERNOON. AS OF 415 AM...A VERY COMPLICATED WEATHER EVENT IN THE OFFING. THE LATEST RADAR IMAGES INDICATED THAT WIDESPREAD LIGHT RAIN WAS SPREADING NORTH ACROSS NE GA AND THE WESTERN CAROLINAS. NAM INDICATES THAT 305-315K ISENTROPIC LIFT WILL INCREASE THROUGH DAYBREAK...THEN BECOMES SCT DURING THE REST OF THE DAY. HOWEVER...A FIELD OF MID LEVEL Q-VECTOR CONVERGENCE WILL SLIDE ACROSS THE FORECAST AREA FROM MID DAY THROUGH SUNSET. I WILL INCREASE POPS TO CATE ACROSS THE MTNS AND FOOTHILLS THROUGH MID DAY. A STRONG COLD FRONT IS EXPECTED TO SWEEP WEST TO EAST BETWEEN 21-00Z. THE STRONG...COLD...MOIST NW H85 WINDS WILL REMAIN ACROSS THE NC MTNS THROUGH TONIGHT. SOUTHWEST WINDS WILL INCREASE ACROSS THE CWA AHEAD OF THE APPROACHING COLD FRONT. THIS AFTERNOON...WINDS ACROSS THE FOOTHILLS AND PIEDMONT WILL INCREASE TO 20 TO 25KTS WITH GUSTS ABOVE 40 KTS DURING THE LATE AFTERNOON AND EVENING. ACROSS THE MTNS...WINDS WILL ALSO INCREASE SHARPLY DURING THE MID DAY. HOWEVER...BOTH THE NAM AND GFS INDICATE THAT H85 WINDS WILL REACH 50-55 KTS BETWEEN 0-6Z. I WILL HIGHLIGHT THE FOOTHILLS AND PIEDMONT WITH A WIND ADVISORY FROM NOON THROUGH MIDNIGHT. ACROSS THE MTNS...THE ADVISORY WILL HIGHLIGHT THE NOON TO 6 AM PERIOD. NRN MTN AREAS WILL SEE GUSTS AROUND 50KTS...HIGHLIGHT WITH A HIGH WIND WARNING FROM NOON TO 6 AM. THE ENVIRONMENT ALONG AND AHEAD OF THE COLD FRONT WILL BE A HIGH SHEAR AND LOW CAPE ENVIRONMENT. THE 0-1 KM HELICITY AHEAD OF THE FRONT ARE FORECAST TO RANGE FROM 250-300 M2/S2. FORECAST SOUNDINGS INDICATE A THIN LAYER OF CAPE BETWEEN 250-300 J/KG. THE GREATEST 0-3 KM EHI...APPROACHING .8 M2/S2...IS EXPECTED TO OCCUR ALONG AND EAST OF THE I-77 CORRIDOR DURING THE LATE AFTERNOON. IN ADDITION...SHERB VALUES WITHIN THE I-77 CORRIDOR IS FORECAST TO EXCEED 1 AROUND 21Z. IT APPEARS THAT A QLCS SVR WIND EVENT MAY OCCUR ACROSS THE I-77 CORRIDOR LATE THIS AFTERNOON. THE SVR TSRA THREAT WILL BE HIGHLIGHTED IN THE HWO. TONIGHT...H85 TEMPERATURES WILL RAPIDLY COOL TO -10 TO -14 C ACROSS THE TN BORDER COUNTIES. THE COMBINATION OF STRONG NW WINDS AND DEEP MOISTURE SHOULD SUPPORT SHSN ALONG THE WESTERN SLOPES OF THE SOUTHERN APPALACHIANS THROUGH TONIGHT. IN ADDITION...WEAK INSTABILITY MAY LINGER WITHIN THE LLVL NW FLOW DURING THE MID EVENING...SUPPORTING MOD SHSN. MIN TEMPERATURES ARE FORECAST TO RANGE FROM THE TEENS TO THE L20S ACROSS THE MTNS...NEAR 30 EAST. THE COLD TEMPERATURES SHOULD YIELD SNOW RATIOS AT LEAST 20 TO 1. EVENT SNOWFALL ACROSS THE TN BORDER COUNTIES IS FORECAST TO RANGE FROM 2-3 INCHES...WILL HIGHLIGHT WITH A WINTER WEATHER ADVISORY. && .SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/... AS OF 230 PM WEDNESDAY...AS THE UPPER TROF MOVES FARTHER OFFSHORE THURSDAY NIGHT...A FLAT UPPER RIDGE MOVING EAST WILL PROVIDE FOR NEARLY ZONAL FLOW ALOFT THROUGH MOST OF THE PERIOD. THIS WILL CARRY HIGH PRESSURE ACROSS THE CAROLINAS THURSDAY NIGHT AND OFF THE COAST ON FRIDAY. THIS WILL ALLOW FOR TEMPS TO REBOUND NICELY TO SOMETHING NEAR NORMAL FOR FRIDAY. WARM ADVECTION SHOULD KICK IN ON SATURDAY THAT WILL RAISE TEMPS ANOTHER FEW DEGREES IN SPITE OF AN INCREASE IN CLOUD COVER AND SHOWER CHANCES. THIS DEVELOPMENT WILL BE COURTESY OF A WEAK WAVE MOVING THROUGH THE FLAT RIDGE ON SATURDAY...WHICH IS BY NO MEANS CERTAIN. THE GFS IS MOST PRONOUNCED WITH THE SHORT WAVE ON SATURDAY BUT IT REMAINS DISORGANIZED. HOWEVER...SOME UPPER DIVERGENCE AND DPVA ACT ON DEEPENING MOISTURE TO DEVELOP PRECIP INTO THE FCST AREA. MEANWHILE...THE NAM AND ECMWF BARELY SHOW ANY WAVE FEATURE AND THAT IS REFLECTED IN A LACK OF FORCING AND RESPONSE AS BOTH MODELS KEEP US DRY ON SATURDAY. THE FORECAST WILL KEEP A SMALL POP DEVELOPING INTO SATURDAY AFTERNOON MOSTLY AS A LEGACY FROM THE PREVIOUS FCST GIVEN THE NEW GFS WHICH STILL DEVELOPS PRECIP. THE ONSET COULD BE EARLY ENOUGH FOR A BRIEF PERIOD OF HIGH ELEVATION SNOW OVER THE SMOKIES AND BALSAMS...OTHERWISE IT SHOULD BE RAIN. THIS COULD EASILY BE ELIMINATED IN SUBSEQUENT FCSTS. && .LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/... AS OF 200 PM EDT WEDNESDAY...LATEST GLOBAL MODELS HAVE COME INTO BETTER AGREEMENT ON TIMING AND TRACK OF A MILLER-A TYPE LOW MOVING UP ALONG THE SE COAST LATE SUN INTO MONDAY. MODELS AGREE THAT A WAVE OF LOW PRESSURE WILL DEVELOP ALONG A SURFACE BOUNDARY OVER THE CENTRAL GULF COAST EARLY SUN AS A NORTHERN STREAM UPPER ENERGY DIGS INTO THE LOWER MISSISSIPPI VALLEY. THIS LOW WILL TRACK EASTWARD ACROSS SOUTHERN AL/GA SUN NIGHT AND MOVES OFF THE SE COASTS BY 12Z MONDAY. POPS RAMP UP FROM WEST TO EAST THRU SUN AS DEEP MOISTURE FLUX INCREASES AHEAD OF THE APPROACHING LOW. THE BEST CHANCE OF PRECIP WILL OCCUR SUN NIGHT INTO EARLY MON AS THE LOW MOVES SE OF THE AREA. LATEST MODELS INDICATE THAT THERMAL PROFILE WILL CONSIDERABLY COOL OFF BY SUN NIGHT AS 1030+MB CANADIAN HIGH PRESSURE BUILDS TO OUR NORTH...LEADING TO SOME P-TYPE ISSUE MAINLY ACROSS THE NORTHERN ZONES OF THE CWA. USING A TOP-DOWN METHOD...I/VE MENTIONED WINTRY MIX OVER THE NORTHERN NC MTNS AND PORTIONS OF OUR NE ZONES SUN NIGHT INTO MON MORNING. ELSEWHERE WILL SEE A SOLID RAIN EVENT. POPS TAPER OFF BY MON AFTERNOON AS THE LOW PULLS FURTHER NE AWAY FROM THE REGION. EXPECT DRY WEATHER WITH MODERATING TEMPS MON THRU WED AS HIGH PRESSURE CENTERED OFF THE EAST COAST BRINGS MOIST RETURN FLOW TO THE REGION. && .AVIATION /19Z WEDNESDAY THROUGH MONDAY/... AT KCLT...THE CENTER OF 990 MB LOW WILL TRACK FROM THE OHIO RIVER VALLEY TO THE NEW ENGLAND COAST THROUGH THE TAF PERIOD. LLVL LIFT AND DEEP MOISTURE WILL SWEEP NORTH AHEAD OF APPROACHING COLD FRONT THIS MORNING AND AFTERNOON. -SHRA WITH IFR CEILINGS IS EXPECTED DURING THE EARLY MORNING DAYLIGHT HOURS. FROPA IS EXPECTED BETWEEN 22-02Z ACROSS THE TERMINAL. AS THE FRONT APPROACHES...SW WILL STRENGTHEN THROUGH THE AFTERNOON...WITH GUSTS NEAR 40 KTS. IN THE WAKE OF THE FRONT...WIND WILL VEER FROM THE NW WITH GUSTS IN THE MID TO UPPER 30 KTS. ELSEWHERE...IFR CEILINGS AND -SHRA WILL INCREASE AHEAD OF AN APPROACHING COLD FRONT THIS MORNING. BY MID DAY...VFR CONDITIONS WITH SW WINDS STRENGTHENING SIGNIFICANTLY...WITH GUSTS IN THE MID TO UPPER 30 KTS. IN THE WAKE OF THE FRONT...WIND WILL VEER FROM THE NW WITH GUSTS IN THE MID TO UPPER 30 KTS. OUTLOOK...DRY HIGH PRESSURE WILL REMAIN OVER THE WESTERN CAROLINAS THROUGH THE REMAINDER OF THE WORK WEEK. CONFIDENCE TABLE... 19-01Z 01-07Z 07-13Z 13-19Z KCLT HIGH 93% HIGH 100% HIGH 100% HIGH 100% KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100% KAVL MED 74% HIGH 100% HIGH 100% HIGH 100% KHKY HIGH 95% HIGH 100% HIGH 100% HIGH 100% KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100% KAND HIGH 94% HIGH 100% HIGH 100% HIGH 100% THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE) WWW.WEATHER.GOV/GSP/AVIATION_TABLES && .FIRE WEATHER... ALTHO TEMPS WILL BE WELL BELOW NORMAL ON THURSDAY...THE AIR MASS MOVING IN BEHIND THE FRONT TONIGHT WILL BE VERY DRY...SUCH THAT RH SHOULD DROP WELL DOWN INTO THE TEENS EAST OF THE MTNS IN THE AFTERNOON. PRECIPITATION TODAY WILL PROBABLY NOT AMOUNT TO ENOUGH TO WET DOWN THE FUELS. THERE SHOULD BE ENOUGH RESIDUAL WIND GUSTINESS TO RAISE THE POSSIBILITY OF DANGEROUS FIRE CONDITIONS THURSDAY AFTERNOON. AFTER CONSULTATION WITH LAND MANAGERS...A FIRE WEATHER WATCH WILL BE ISSUED FOR NC EAST OF THE MTNS. TEMPS WILL BE COOLER OVER THE NC MTNS AND SOME LOCATIONS NEAR THE TN BORDER MIGHT BE SNOW COVERED...SO NO WATCH THERE. ELSEWHERE...WIND WILL BE LIGHTER...BUT ADDITIONAL COORDINATION WILL BE NEEDED ACROSS SOUTH CAROLINA AND NE GEORGIA...FOR A POSSIBLE FIRE DANGER STATEMENT. && .GSP WATCHES/WARNINGS/ADVISORIES... GA...WIND ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR GAZ010-017-018- 026-028-029. NC...FIRE WEATHER WATCH FROM THURSDAY MORNING THROUGH THURSDAY AFTERNOON FOR NCZ035>037-056-057-068>072-082-501>510. WIND ADVISORY UNTIL 6 AM EDT THURSDAY FOR NCZ048-051>053-058- 059-062>065-501-503-505-507-509. WIND ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR NCZ035>037-056- 057-068>072-082-502-504-506-508-510. WINTER WEATHER ADVISORY FROM 6 PM THIS EVENING TO 9 AM EDT THURSDAY FOR NCZ033-048>052-058. WIND CHILL ADVISORY FROM 6 PM THIS EVENING TO 9 AM EDT THURSDAY FOR NCZ033-048>052-058. HIGH WIND WARNING UNTIL 6 AM EDT THURSDAY FOR NCZ033-049-050. SC...WIND ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR SCZ001>014-019. && $$ SYNOPSIS...JOH NEAR TERM...MCAVOY SHORT TERM...PM LONG TERM...JOH AVIATION...MCAVOY FIRE WEATHER...
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
140 PM EDT WED MAR 12 2014 .SYNOPSIS... A COLD FRONT WILL PUSH THROUGH THE FORECAST AREA TODAY WITH COOL HIGH PRESSURE BUILDING IN ON THURSDAY. THE AIRMASS WILL SLOWLY MODERATE WARMER INTO SATURDAY...BEFORE A BROAD AND COLDER UPPER LEVEL TROF BUILDS IN SUNDAY THROUGH MONDAY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 130 PM EDT...A LINE OF SHOWERS IS DEVELOPING AS EXPECTED OVER ERN TN. CUT BACK SHOWER ACTIVITY CONSIDERABLY AHEAD OF THE LINE OVER THE WESTERN CAROLINAS AND NE GA THIS AFTN...BUT HAVE STILL MAINTAINED LIKELY POPS ALONG THE PROBABLE MCS TRACK WHICH WILL PRIMARILY BE ACROSS NORTH CAROLINA. AS OF 1110 AM...LOW CLOUDS ARE HOLDING ON A LITTLE LONGER THAN EXPECTED OVER THE FOOTHILLS AND PIEDMONT OF THE WRN CAROLINAS AND NE GA THIS MORNING. AND THE LATEST NAM HAS COME IN WITH IT/S GREATEST INSTABILITY JUST A LITTLE EAST OF THE FORECAST AREA AROUND 21 UTC THIS AFTN. THERE IS STILL A LINE FINE OVER ERN TN WHICH REPRESENTS THE SFC COLD FRONT. CONVECTION IS SLOWLY STRENGTHENING ALONG THE NRN PORTION OF THE LINE WHERE THERE IS GREATER FORCING...BUT THE SOUTHERN END SHOULDN/T DEVELOP INTO DEEP CONVECTION UNTIL IT GETS EAST OF THE MOUNTAINS. THE THINKING NOW IS THAT IT WILL STEADILY STRENGTHEN ONCE EAST OF THE MOUNTAINS...BUT THAT THE GREATEST SEVERE POTENTIAL WILL BE A LITTLE EAST OF THE FORECAST AREA. STILL...THE I77 CORRIDOR IS THE AREA MOST UNDER THE GUN THIS AFTN IN OUR FA. ALSO...WINDS IN THE BNDRY LAYER JUST BEHIND THE LINE ARE QUITE STRONG...AND EVEN A RELATIVELY WEAK LINE OF SHOWERS HAS THE POTENTIAL TO PRODUCE DAMAGING WINDS. OVER THE UPSTATE AND NE GA THE ATMOSPHERE LOOKS MORE CAPPED...THOUGH DEWPOINTS WILL BE A LITTLE HIGHER. OVERALL...THE HRRR TREND OF THE LINE OF CONVECTION NOT DEVELOPING VERY FAR INTO THE UPSTATE LOOKS GOOD AND HAS BEEN REFLECTED IN THE GRIDS. BUT EVEN HERE 40 KT GRADIENT WIND GUSTS ARE POSSIBLE AND THE WIND ADVISORY STILL LOOKS VALID. AS OF 630 AM...I WILL UPDATE THE FORECAST WITH THE RECENT OBSERVATIONS ACROSS THE FORECAST AREA. IN ADDITION...I WILL INCREASE POPS EARLY THIS MORNING...BASED OFF OF THE RECENT RADAR DATA. IN ADDITION...I WILL ADD TIMING AND PLACEMENT DETAILS FOR A LINE OF TSRA TO SWEEP ACROSS THE NRN I-77 CORRIDOR THIS AFTERNOON. AS OF 415 AM...A VERY COMPLICATED WEATHER EVENT IN THE OFFING. THE LATEST RADAR IMAGES INDICATED THAT WIDESPREAD LIGHT RAIN WAS SPREADING NORTH ACROSS NE GA AND THE WESTERN CAROLINAS. NAM INDICATES THAT 305-315K ISENTROPIC LIFT WILL INCREASE THROUGH DAYBREAK...THEN BECOMES SCT DURING THE REST OF THE DAY. HOWEVER...A FIELD OF MID LEVEL Q-VECTOR CONVERGENCE WILL SLIDE ACROSS THE FORECAST AREA FROM MID DAY THROUGH SUNSET. I WILL INCREASE POPS TO CATE ACROSS THE MTNS AND FOOTHILLS THROUGH MID DAY. A STRONG COLD FRONT IS EXPECTED TO SWEEP WEST TO EAST BETWEEN 21-00Z. THE STRONG...COLD...MOIST NW H85 WINDS WILL REMAIN ACROSS THE NC MTNS THROUGH TONIGHT. SOUTHWEST WINDS WILL INCREASE ACROSS THE CWA AHEAD OF THE APPROACHING COLD FRONT. THIS AFTERNOON...WINDS ACROSS THE FOOTHILLS AND PIEDMONT WILL INCREASE TO 20 TO 25KTS WITH GUSTS ABOVE 40 KTS DURING THE LATE AFTERNOON AND EVENING. ACROSS THE MTNS...WINDS WILL ALSO INCREASE SHARPLY DURING THE MID DAY. HOWEVER...BOTH THE NAM AND GFS INDICATE THAT H85 WINDS WILL REACH 50-55 KTS BETWEEN 0-6Z. I WILL HIGHLIGHT THE FOOTHILLS AND PIEDMONT WITH A WIND ADVISORY FROM NOON THROUGH MIDNIGHT. ACROSS THE MTNS...THE ADVISORY WILL HIGHLIGHT THE NOON TO 6 AM PERIOD. NRN MTN AREAS WILL SEE GUSTS AROUND 50KTS...HIGHLIGHT WITH A HIGH WIND WARNING FROM NOON TO 6 AM. THE ENVIRONMENT ALONG AND AHEAD OF THE COLD FRONT WILL BE A HIGH SHEAR AND LOW CAPE ENVIRONMENT. THE 0-1 KM HELICITY AHEAD OF THE FRONT ARE FORECAST TO RANGE FROM 250-300 M2/S2. FORECAST SOUNDINGS INDICATE A THIN LAYER OF CAPE BETWEEN 250-300 J/KG. THE GREATEST 0-3 KM EHI...APPROACHING .8 M2/S2...IS EXPECTED TO OCCUR ALONG AND EAST OF THE I-77 CORRIDOR DURING THE LATE AFTERNOON. IN ADDITION...SHERB VALUES WITHIN THE I-77 CORRIDOR IS FORECAST TO EXCEED 1 AROUND 21Z. IT APPEARS THAT A QLCS SVR WIND EVENT MAY OCCUR ACROSS THE I-77 CORRIDOR LATE THIS AFTERNOON. THE SVR TSRA THREAT WILL BE HIGHLIGHTED IN THE HWO. TONIGHT...H85 TEMPERATURES WILL RAPIDLY COOL TO -10 TO -14 C ACROSS THE TN BORDER COUNTIES. THE COMBINATION OF STRONG NW WINDS AND DEEP MOISTURE SHOULD SUPPORT SHSN ALONG THE WESTERN SLOPES OF THE SOUTHERN APPALACHIANS THROUGH TONIGHT. IN ADDITION...WEAK INSTABILITY MAY LINGER WITHIN THE LLVL NW FLOW DURING THE MID EVENING...SUPPORTING MOD SHSN. MIN TEMPERATURES ARE FORECAST TO RANGE FROM THE TEENS TO THE L20S ACROSS THE MTNS...NEAR 30 EAST. THE COLD TEMPERATURES SHOULD YIELD SNOW RATIOS AT LEAST 20 TO 1. EVENT SNOWFALL ACROSS THE TN BORDER COUNTIES IS FORECAST TO RANGE FROM 2-3 INCHES...WILL HIGHLIGHT WITH A WINTER WEATHER ADVISORY. && .SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... AS OF 330 AM WEDNESDAY...STRONG CHANNELED SHORT WAVE CROSSES THE AREA THURSDAY AS AN UPPER TROF MOVES EAST OF THE AREA. ANY LINGERING MTN SNOW SHOWERS WILL DISSIPATE QUICKLY THU MORNING AS LOW LEVEL DRIES UP. TIGHT PRESSURE GRADIENT WILL RELAX THRU THE DAY AS HIGH PRESSURE BUILDS INTO THE AREA. HOWEVER...GUSTY WINDS COULD LINGER THROUGH THE MORNING. VERY LOW RH IS LIKELY AS THE AIR MASS MOVING INTO THE AREA IS VERY DRY. THERE IS SOME CONCERN ON THURSDAY THAT PORTIONS OF THE FCST AREA WILL FLIRT WITH RED FLAG FIRE CONDITIONS BECAUSE OF THE VERY LOW RH IN THE AFTERNOON AND POTENTIALLY LINGERING WIND GUSTS OVER THE MTNS. EXPECT HIGHS 10 TO 15 DEGREES BELOW NORMAL. ZONAL FLOW DEVELOPS THU NITE AND CONTINUES FRI AND FRI NITE. SOME WEAK SHORT WAVES MOVE ACROSS THE AREA THRU THE ZONAL FLOW. AT THE SFC...THE HIGH PRESSURE CENTER MOVES OVER THE AREA THU NITE THEN OFF SHORE FRI. A WEAK FRONTAL SYSTEM DROPS INTO THE OH VALLEY FRI NITE AS A LOW PRESSURE CENTER MOVES INTO THE SRN PLAINS. MOISTURE RETURNS ACROSS THE AREA IN THE DEVELOPING SLY FLOW AS THE HIGH MOVES OFF SHORE. EXPECT MAINLY CLOUDS FROM THIS RETURN MOISTURE. PRECIP SHOULD HOLD OFF UNTIL AFTER FRI NITE. HIGHS FRI WILL RISE TO NEAR NORMAL. LOWS THU NITE AROUND 10 DEGREES BELOW NORMAL WILL RISE A LITTLE ABOVE NORMAL FRI NITE. && .LONG TERM /SATURDAY THROUGH TUESDAY/... AS OF 145 AM EDT WED...THERE IS STILL MUCH UNCERTAINTY IN THE EXT RANGE FCST. THE ULVL PATTERN/ENERGY AND MASS FIELDS ARE NOT WELL AGREED UPON WHICH LEADS TO VARYING SFC SENSIBLE WX SOLNS BTW THE MAIN OP MODELS. THE INCOMING COLD FRONT SAT IS MORE PRONOUNCED AND HAS GREATER GOM MOISTURE FLUX THAN THE CWC/ECMWF. HOWEVER...THERE IS DECENT AGREEMENT WITH THE LLVL THERMAL FIELDS AND WILL COUNT ON MAINLY ALL RAIN IN ISENT WARM SECTOR LIFT. THERE COULD BE BRIEF -SNSH ACROSS THE HIGHEST NC MTN TERRAIN WITH NO SIGFNT ACCUMS THROUGH 14Z SAT. THE BIGGER DIFFERENCE IN THE MODELS OCCURS SUN THROUGH TUE WITH THE EVOLUTION OF THE AFOREMENTIONED SFC BOUNDARY. WHILE THE GFS IS MAINTAINING NEARLY UNIFORM FLOW THROUGH A DEEP LAYER AND THUS A NEARLY STATIONARY COASTAL SFC FRONT...THE ECMWF AND CMC DEVELOP A STRONG ULVL TROF AND COASTAL MILLER/A CYCLOGENESIS SUN NIGHT. THIS LATTER SCENARIO WOULD BRING IN MUCH GREATER MOISTURE AND ALONG WITH SOME MEASURE OF LOWERING PARTIAL THICKNESSES AND DIURNAL COOLING...SN OR A RA/SN MIX SUN AND MON NIGHTS. THIS IDEA WAS GIVEN A LITTLE MORE WEIGHT THAN THE TOTALLY SUPPRESSED AND DRY GFS SOLN. THE GOING MID CHANCE POPS STILL LOOK GOOD SUN NIGHT THROUGH MON NIGHT WITH SNOW ACCUMS ACROSS THE NC MTNS EARLY MON AND PERHAPS LOW END ACCUMULATING SNOW INTO THE NC FOOTHILLS AND PIEDMONT MON NIGHT. TEMPS WILL BEGIN THE PERIOD RIGHT AROUND NORMAL AND LIKELY DROP TO 8-10 DEGREES BELOW NORMAL BY MON WITH WINDS SHIFTING NE/LY AS A CANADIAN HIGH BUILDS TO THE NORTH AND A BROAD ULVL TROF DEVELOPS OVER THE ERN CONUS. && .AVIATION /18Z WEDNESDAY THROUGH MONDAY/... AT KCLT...THE CENTER OF 990 MB LOW WILL TRACK FROM THE OHIO RIVER VALLEY TO THE NEW ENGLAND COAST THROUGH THE TAF PERIOD. LLVL LIFT AND DEEP MOISTURE WILL SWEEP NORTH AHEAD OF APPROACHING COLD FRONT THIS MORNING AND AFTERNOON. -SHRA WITH IFR CEILINGS IS EXPECTED DURING THE EARLY MORNING DAYLIGHT HOURS. FROPA IS EXPECTED BETWEEN 22-02Z ACROSS THE TERMINAL. AS THE FRONT APPROACHES...SW WILL STRENGTHEN THROUGH THE AFTERNOON...WITH GUSTS NEAR 40 KTS. IN THE WAKE OF THE FRONT...WIND WILL VEER FROM THE NW WITH GUSTS IN THE MID TO UPPER 30 KTS. ELSEWHERE...IFR CEILINGS AND -SHRA WILL INCREASE AHEAD OF AN APPROACHING COLD FRONT THIS MORNING. BY MID DAY...VFR CONDITIONS WITH SW WINDS STRENGTHENING SIGNIFICANTLY...WITH GUSTS IN THE MID TO UPPER 30 KTS. IN THE WAKE OF THE FRONT...WIND WILL VEER FROM THE NW WITH GUSTS IN THE MID TO UPPER 30 KTS. OUTLOOK...DRY HIGH PRESSURE WILL REMAIN OVER THE WESTERN CAROLINAS THROUGH THE REMAINDER OF THE WORK WEEK. CONFIDENCE TABLE... 17-23Z 23-05Z 05-11Z 11-17Z KCLT HIGH 84% HIGH 100% HIGH 100% HIGH 100% KGSP HIGH 96% HIGH 100% HIGH 100% HIGH 100% KAVL MED 61% HIGH 100% HIGH 100% HIGH 100% KHKY HIGH 87% HIGH 100% HIGH 100% HIGH 100% KGMU HIGH 94% HIGH 100% HIGH 100% HIGH 100% KAND HIGH 86% HIGH 100% HIGH 100% HIGH 100% THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE) WWW.WEATHER.GOV/GSP/AVIATION_TABLES && .GSP WATCHES/WARNINGS/ADVISORIES... GA...WIND ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR GAZ010-017-018- 026-028-029. NC...WIND ADVISORY UNTIL 6 AM EDT THURSDAY FOR NCZ048-051>053-058- 059-062>065-501-503-505-507-509. WIND ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR NCZ035>037-056- 057-068>072-082-502-504-506-508-510. WINTER WEATHER ADVISORY FROM 6 PM THIS EVENING TO 6 AM EDT THURSDAY FOR NCZ033-048>052-058. HIGH WIND WARNING UNTIL 6 AM EDT THURSDAY FOR NCZ033-049-050. SC...WIND ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR SCZ001>014-019. && $$ SYNOPSIS...SBK NEAR TERM...MCAVOY/NED SHORT TERM...RWH LONG TERM...SBK AVIATION...MCAVOY