Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 01/03/20

Area Forecast Discussion
National Weather Service Caribou ME
1054 PM EST Thu Jan 2 2020 .SYNOPSIS... High pressure slides offshore overnight as a warm front will lift north across the region. Weak high pressure builds Friday afternoon into Saturday. Low pressure tracks from the Mid- Atlantic states Saturday morning to a position south of Nova Scotia by Sunday. High pressure builds Sunday afternoon into Monday. A weak trough of low pressure crosses Monday night followed by high pressure over the area Tuesday. Coastal low pressure is expected Wednesday. && .NEAR TERM /THROUGH FRIDAY/... 1055pm update: Radar was showing echoes filling in as the warm front lifts north. Tweaked precip chances to bring them up a bit from the previous forecast. The latest run of the HRRR and NAMNEST matched quite well w/the placement. Stayed close to the daycrew`s snowfall of an inch or less. Temps were adjusted to the fit the latest obs. Not expected much drop overnight given the cloud cover. Previous discussion... High clouds will continue to migrate over the forecast area this evening as warm air advection takes place with a passing warm front. Moisture works its way into the region, with added lift creating the chance of snow showers across the north this evening, tapering after midnight. Increased QPF values a little, mainly across eastern Aroostook. With the warm air advancing, the DGZ is quite elevated, so snow ratios will remain lower, close to 10:1. The result is a forecast for around half an inch to an inch of snow across the far north and eastern Aroostook towns/cities through tonight. Warm air continues to surge into the area Friday. Widespread highs in the 40s across Downeast w/ highs in the mid-30s in the north are expected. Most of the day will keep clouds across the northern and central areas, with Downeast thinning out a bit towards the afternoon. && .SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY/... Mild temperatures will be in place with lows ranging from the upper 20s to above freezing in much of the Downeast region. These lows are up to 20F higher than normal. A cold front will be swinging through the area with stratocu and no precip. Still have some concerns about some fog for Bangor and Downeast, but confidence not high enough for a mention at this point. There`s not much cold air behind the cold front as highs will remain above freezing for much of the area and some 40s along the coast...some 10F above normal. Clouds increase later in the day with low pressure system that will be moving to our south. Guidance continues to show a wide range of solutions from model to model and run to run. Used a multi-model, multi- run ensemble approach that places highest PoPs and QPF along the coast and tapers to nearly nothing in northern Aroostook County. Highest confidence for plowable snow is on the coast given the expected track with maximum snow up to around 4". This solution mirrors the GEFS mean. The storm is expected to deepen dramatically as it passes to the south. The upper trough passage will help generate some lighter snow amounts further north. Cold advection occurs Sunday with forecast highs around 10F cooler and closer to normal. && .LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/... High pressure builds more quickly than previously expected and have moved lows downward for Sunday night and may need to go down further...especially in the North Woods. Monday looks like a fair, but cool day with below normal highs and light winds. A weak surface trough crosses Monday night with some flurries possible and separates Monday`s high from another transient high that will build Tuesday. The big action for the long term starts Tuesday night and runs into Wednesday night as a coastal low tries to organize. This low will come much closer to Maine than the weekend system...if not over the state. Models continue to struggle phasing northern and southern streams and offer a variety of tracks ranging from over the state with mixed precip well offshore. Confidence increased enough to progress to likely PoPs and am inclined to go mostly snow except some mixing in the Downeast region south of our expected track, but confidence is not high in a mostly snow outcome yet. && .AVIATION /04Z FRIDAY THROUGH TUESDAY/... NEAR TERM: Southern terminals at BGR and BHB will remain dry and VFR through tomorrow. To the north, -SHSN is expected tonight, especially from KFVE to KPQI. Conditions will remain MVFR for most of this evening and overnight, with possibility of IFR in lower ceiling/vis associated with the snow showers. SHORT TERM: Friday night into early Saturday...Expect MVFR cigs to be the primary issue, but can`t rule out IFR cigs for higher terrain such as FVE and GNR. Also can`t rule out some IFR vis in fog towards BHB and BGR later Friday night. Saturday...Conditions will improve to predominately VFR. Saturday night into early Sunday...MVFR cigs, tempo IFR vis in snow north of BGR, and a period of IFR vis in snow is likely for BGR, BHB, and Machias. Monday and Tuesday...VFR except a slight chance of a brief period of snow on Monday night. && .MARINE... NEAR TERM: Below SCA conditions as both winds and seas remain below thresholds. Waves remain 2 to 4 ft through Friday. SHORT TERM: Gale conditions will develop Sunday and continue into Sunday night. Another gale is possible Wednesday night into Thursday. && .CAR WATCHES/WARNINGS/ADVISORIES... ME...None. MARINE...None. && $$ Near Term...Hewitt
National Weather Service Hastings NE
621 PM CST Thu Jan 2 2020 .SHORT TERM...(Now through Friday) Issued at 1219 PM CST Thu Jan 2 2020 Aloft: Aircraft winds along with WV imagery and RAP tropopause analyses indicated a deep trof from the Nrn Plns to Nrn MX...with a moderate-amplitude ridge over the Ern USA and a high-amplitude ridge off the W Coast. The trof will slowly migrate acrs NEB/KS tonight into Fri morning...and it will be E of the CWA by 18Z/Fri. This will shift winds from W to NW. A shrtwv trof currently over AB will dive SE into the Nrn Plns tomorrow and strengthen. Surface: 992 mb low pres was near Lk Superior. The wk cool front associated with this low moved thru the CWA this morning...and wk 1009 mb high pres was over NEB. This high will be overtaken by a stronger 1020 mb high rapidly sliding down the lee side of the Rckys tonight and tomorrow. Meanwhile...a small/wk low pres sys will form over the Nrn Plns and the sfc low will be near MSP by 00Z/Sat. This afternoon: Variable sky. Highs will range from 40-47F with about 40F in the Tri-Cities. Some occasional gustiness will add a chill in the air at times. Otherwise...a pretty nice day where sun prevails. Tonight: Variable sky. Clear at times...then partly-mostly cldy after 06Z as some 5-10K ft clds streak SE acrs the CWA. Another relatively mild night with lows in the 20s. Fri: Mostly sunny. Blustery...espcly E of Hwy 183. NW winds will gust up to 30 kt. The GFS is even more aggressive with G35 kt psbl due to its stronger low-lvl winds. NAM isn`t as aggressive...but be aware that winds could be a tad higher than we`re currently advertising...if the GFS is right. Near normal temps with highs 32-42F from N-S. Around 35F in the Tri-Cities. .LONG TERM...(Friday night through Thursday) Issued at 1219 PM CST Thu Jan 2 2020 Aloft: The flow will remain progressive and low-amplitude thru next Thu...but there will be a trend toward increased amplitude mid-next week. The ridge currently off the W coast will move E and deamplify as it crosses the Plns Sat. A wk shrtwv trof will follow Sat night. Another trof will move in from the Pac and cross the rgn Mon. This trof is fcst to amplify some...espcly as it heads E Mon-Tue. A moderate-amplitude ridge will arrive over the plns Wed...with another more significant trof fcst to envelop the Wrn USA. Surface: The cool front associated with the MN low (see above) will sink thru NEB/KS Fri night. A strong low will form over AB Sat. The burst of downslope flow will induce warm frontogenesis. This front will cross the CWA Sat afternoon. The CWA will not be in the warm sector long as the cool front will move thru Sat the sfc low heads E acrs Srn Canada. High pres arrives Sun. A stronger cold front will cross the CWA Mon night or Tue... but the core of the coldest air will miss and stay E of the rgn. The next low pres sys to affect the rgn is slated for next Thu. Temps: cont to average slightly warmer than normal by a few degs. Precip: Nothing of significance...and little of insignificance. Just an outside chance for some light flurries centered around Fri night and then flurries or sprinkles Mon. Neither of these are in the fcst yet due to mdl uncertainty...but may need to be added. Arctic Cold and the Pattern: Temps have averaged much warmer than normal since mid Nov. Temps typically swing back-and-forth between warmer and colder than normal on 30-60 day cycles. So we are nearing the end of this warm cycle. We have been seeing high- confidence signals in the ensembles that a pattern change is coming. We`ve seen multiple runs of the EC/GFS/CMC/JMA (Japanese) ensembles and the the CFS mdl that the PNA pattern will become strongly negative which is a high-amplitude ridge over the E Pac and trof over the Wrn USA. This allows Arctic air to drain into the Wrn USA and Cntrl/Nrn Plns. So believe much colder wx is on the way...espcly as we get past Jan 10th. && .AVIATION...(For the 00Z KGRI/KEAR TAFS through 00Z Friday) Issued at 557 PM CST Thu Jan 2 2020 The primary aviation issue will continue to center around the strong low level wind shear expected late tonight developing around 10Z and persisting through mid morning. Ceilings and visibility should remain VFR throughout the period. We do expect increasing clouds late tonight then clearing out again by mid morning with mostly sunny skies throughout much of Friday. The wind will be gusty by late Friday morning and remain gusty out of the west northwest. Some gusts could reach to around 35 mph. && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$ SHORT TERM...Kelley LONG TERM...Kelley AVIATION...Wesely
Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
952 PM EST Thu Jan 2 2020 .SYNOPSIS... Widespread rain will overspread the area through Friday. Dry and cool high pressure will prevail from Sunday through early next week. The next cold front will arrive in the middle of next week. && .NEAR TERM /THROUGH FRIDAY/... As of 940 PM: Rain band continues to shift north across the CWFA, following a deep layer of isentropic upglide atop sfc high pressure. While the upglide will continue thru the rest of the night, it becomes increasingly shallow, though as LLJ strengthens the HRRR (for one) depicts a resurgence in precip generation later on, especially in the Savannah River valley and near the south-facing Escarpment. Temp trends from the prev fcst are holding up pretty well; they still look to warm a little overnight as WAA aloft lowers to the sfc, though some of the higher-res sources now hang onto the colder temps longer than before. Readings by daybreak expected arnd 50 F over the mtns and SE of I-85 as the "wedge-like" airmass retreats. With temps beginning the day so warm...temps should have no problem reaching the lower to mid 60s across the FA by the aftn in continued WAA prior to the approaching cold front. Precip amts will begin to add up across the SW NC mtns overnight where up to 2.5 inches are possible over the favored sw-facing upslope regions. This shouldn`t be enough for significant hydro issues as the QPF/FFG ratios remain generally under 40% in any given 6-hr period. However...isol small stream and/or poor drainage area flooding is will keep mention in the HWO. Another concern overnight will the the potential for strong winds mixing to the sfc across the higher terrain. The guidance has been consistent with developing a 60+ 850mb jet reaching the mtns aft 00z and crossing thru daybreak. Yet...the latest soundings are also showing a strong llvl inversion developing with the strongest winds remaining abv the top of the inversion. Rather gusty conditions will develop over the mtns especially abv 3500 ft...yet advisory-level winds will likely be limited to abv 5000 ft...thus this scenario will also be maintained in the HWO. && .SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY/... As of 245 PM EST Thursday: The short term will be a transitional period. Upper level energy dropping through the High Plains will merge with broad troughing and moist southwest flow atop the region Saturday before quickly pushing the system offshore while intensifying Sunday. Rain chances and cloud cover will gradually diminish east of the mountains Saturday with most of the meaningful rainfall over by sunrise. Our attention will turn to what may be a fairly potent upper (closed if you believe the GFS) low moving through the region later in the day into Saturday night. Rapid pressure rises behind the front (supported by the descending portion of an 160+ kt jet) coupled with 850 mph winds will support developing gusty northwest winds (possibly advisory level) late Saturday into Saturday night focused across the mountains. A decent amount of lingering low level moisture, the strengthening upslope flow near the TN border and upper support should support a 6-12 hour window for snow across higher elevations especially near the TN border. Snow will likely be showery in nature, but may be convective in nature (due to cold air aloft and limited BL instability), possibly supporting brief periods of moderate to heavy snow. Have upped snow totals a bit with this forecast package with around two inches now expected at high elevations near the TN border. Cold air advection behind the cold front will lead to temperatures falling fairly rapidly in the late afternoon into the evening, especially across the mountains. Although temperatures will be much colder behind the front, they only fall back to near normal under sunny skies for Sunday. && .LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/... As of 220 PM EST Thursday: Zonal flow aloft and weak high pressure near the surface will support quiet weather to begin the extended period with near to just above normal temperatures. An amplifying short-wave will push through the region mid-week, possible supporting an organized cold frontal passage and a modest band of precipitation. The airmass in place may support snow across higher elevations, especially behind the front associated with possible wrap around moisture. Clear skies and fairly strong 1030+ surface high may support near normal highs and slightly below normal lows to finish off the work week. && .AVIATION /03Z FRIDAY THROUGH TUESDAY/... Isentropic lift atop a cool sfc high will bring a band of rain across the terminals this evening. Cigs will be variable between IFR and low VFR during the rain, with short periods of restricted vsby also possible. The deepest/strongest layer of lift will shift off to the north later tonight, and improvement in vsby and likely cigs will occur in the wake of the rain. However, continued warm advection and an increasingly shallow cool layer should lead to rapid lowering of cigs near dawn, and some areas of fog, with conditions likely near minima for a time. Rain is expected to become widespread again late in the period ahead of developing sfc low. This will lead to some improvement in flt cat via downward motion, but generally IFR to low MVFR will persist until the end of the period at all sites. Outlook: Widespread flight restrictions can be expected into Saturday until the frontal system and a subsequent shortwave trough exit to the east. Confidence Table... 03-09Z 09-15Z 15-21Z 21-00Z KCLT High 85% Low 58% Med 78% Med 79% KGSP High 96% High 81% Med 66% Med 69% KAVL Med 70% Med 60% Low 58% Low 59% KHKY High 90% Med 68% High 85% Med 61% KGMU Med 76% High 86% Med 63% Med 69% KAND Low 58% Med 60% Med 66% High 88% 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: && .GSP WATCHES/WARNINGS/ADVISORIES... GA...None. NC...None. SC...None. && $$ SYNOPSIS...DEO NEAR TERM...SBK/08 SHORT TERM...65 LONG TERM...65 AVIATION...08
Area Forecast Discussion
National Weather Service Jacksonville FL
725 PM EST Thu Jan 2 2020 .UPDATE... Partly cloudy skies will continue across the forecast area Tonight. Area 00z soundings showing a substantial increase in low-level moisture compared to 12z soundings. After Midnight, low-level flow will increase out of the SW from the northeast Gulf of Mexico, causing surface temperatures and dewpoints to slowly rise. Weak low-level lift is indicated, which should support a stratus cloud deck spreading northeast from northeast Gulf of Mexico across much of our forecast area early Friday morning. Have made minimal changes to low temperatures, but changed the diurnal pattern of hourly temperatures/dew points to reflect minimums around Midnight and rising values thereafter. Tricky sky forecast Friday. Should have widespread low cloudiness across the area, as shown by the HRRR, in the morning. Model forecast soundings indicate a very strong thermal inversion just above this cloud deck, which will make it difficult to break up during the day. Should see slow rise in temperatures in warm advection pattern, but cloudiness could result in highs a few degrees below current forecast. Did not change in update as just a few hours of afternoon partial sun could get high temperatures to current forecast. Rain chances Friday appear limited to our western counties...spreading eastward Friday night and Saturday. && .AVIATION... [Through 00Z Saturday] Latest higher-resolution model ensemble guidance and HRRR guidance indicate VFR conditions Tonight. However, after 09Z, will see a surge of low-level moisture across the area from the northeast Gulf of Mexico on 30-40 kt low-level flow, which should create large area of stratiform cloudiness over TAF sites. Latest HRRR suggests Cigs could be IFR...have limited height to OVC010 in 00z TAFs. With model soundings showing a strong inversion above this ceiling, may be tough for ceiling to break...may just see a gradual rise to about BKN025 by 21Z Fri. 5-10kt SE winds this evening will become more southerly later Tonight, with 10-15kt S to SW winds Friday. && .MARINE... Winds increase tonight as high pressure moves east out of the region. Small Craft Exercise Caution headline is in effect for tonight for the offshore waters as winds increase to the 15-20 kt. A cold front approaches the region late Friday and pushes off the coast Saturday morning. Showers and a few thunderstorms will accompany this front. Small Craft Advisories are likely ahead of and behind the front as winds and seas increase. Gale force gusts will also be possible late Saturday through Sunday morning mainly for the offshore waters. Gale Watch may be needed. Winds and seas begin to subside on Sunday as high pressure builds in. Rip Currents: low to moderate through Friday. && .PRELIMINARY POINT TEMPS/POPS... AMG 60 78 60 68 37 / 10 60 70 60 0 SSI 61 76 61 69 40 / 0 20 60 80 10 JAX 61 80 64 73 40 / 0 10 60 80 10 SGJ 62 79 63 73 41 / 0 10 30 70 10 GNV 62 81 64 71 39 / 10 20 60 70 10 OCF 63 83 64 73 41 / 10 10 50 70 0 && .JAX WATCHES/WARNINGS/ADVISORIES... FL...None. GA...None. AM...None. &&
Area Forecast Discussion
National Weather Service Lake Charles LA
810 PM CST Thu Jan 2 2020 .DISCUSSION... Wx map shows broad area of low pressure over most of TX/LA region. Radar showing continuous showers and isolated thunderstorms streaming northeastward over all of SE TX/C and S LA this evening. Heavier banding late this afternoon into the early evening hours produced around 2-4" of rainfall across SE Calcasieu/Jeff Davis/Evangeline/Avoyelles parishes, with isolated reports of flooding on roadways. Latest HRRR guidance shows the showers and isolated thunderstorms continuing this evening into the early morning hours, with some enhancement of the rainfall rates between midnight-3 am time frame over the same parishes and further eastward. For this, and this region upgraded to a moderate risk of excessive rainfall during this period, have issued a Flash Flood Watch for Avoyelles, Evangeline, St. Landry, Acadia and Jefferson Davis parishes until 4 AM CST. Afterward, the ending line of precipitation expected to move east of this region by daybreak Friday. DML && .PREV DISCUSSION... /issued 538 PM CST Thu Jan 2 2020/ AVIATION...A band of heavy rain and storms is very gradually moving east toward KLFT and KARA. Those terminals will continue to have gusty south winds, lower ceilings, and br. Near and behind the line KAEX, KLCH, and KBPT will have lighter winds and a period of improving ceilings. Later tonight and into early Fri areas of fog may develop near KBPT and KLCH. A cold front will move into the region at the very end of the period and past KBPT before sunset with the rest of the terminals later. PREV DISCUSSION... /issued 414 PM CST Thu Jan 2 2020/ DISCUSSION... NE-SW oriented bands of showers, with embedded thunderstorms generally along and east of Cameron to Alexandria, will continue to very slowly migrate E the rest of this afternoon and tonight as a lead shortwave trof ejects NE across TX into the Mid MS River Valley. There remains a slight risk of excessive rainfall and severe thunderstorms roughly along and east of the line above through this evening. An otherwise humid night is in store, with patchy fog likely to remain and/or redevelop later tonight into FRI morning. Bulk of rains will be departing the area to the east FRI morning, though the main upper trof axis looming to the west and its associated CDFNT will keep at least a small chance of rain in the forecast. Front is expected to push through the area during the late afternoon into early evening, allowing plenty of time for temperatures to warm into the upper 60s prior to FROPA. Behind the front, brisk NW winds will usher cooler and more so drier air into the area, yielding cooler temperatures FRI night into SAT morning and near seasonal highs SAT afternoon. Another cool night expected SAT night with high pressure at the SFC traversing the area, with a warm-up commencing SUN afternoon as the high scoots off to the east underneath flat westerly flow aloft. The warming will continue until another front pushes through MON night into TUE, accompanied by small rain chances amid limited MSTR and followed by a brief return to near or below seasonal temperatures through WED. A warming trend and increasing rain chances are slated to close out the work week ahead of another approaching upper trof, 13 MARINE... Modest to strong onshore flow will continue across the coastal waters east of Cameron through early evening, with a light and somewhat variable but generally onshore flow prevailing the rest of the night into Friday. Northeast to southwest oriented bands of rain and isolated thunderstorms will continue to gradually progress east through the coastal waters the rest of this afternoon and tonight, finally pushing east of the Lower Atchafalaya River by early afternoon Friday. A cold front is expected to push through the coastal waters during the late afternoon and evening, with a modest to strong offshore flow following its passage lasting through Saturday morning. A small craft advisory will likely be needed for this time period. 13 && .PRELIMINARY POINT TEMPS/POPS... AEX 53 67 40 60 / 90 20 20 0 LCH 57 69 44 64 / 90 20 10 0 LFT 60 68 46 62 / 90 30 20 0 BPT 56 69 43 64 / 70 20 0 0 && .LCH WATCHES/WARNINGS/ADVISORIES... LA...Flash Flood Watch until 4 AM CST Friday for LAZ029-032-033-042- 043. TX...None. GM...Small Craft Advisory until 9 PM CST this evening for GMZ455-472- 475. Small Craft Exercise Caution until 9 PM CST this evening for GMZ435-452. && $$ PUBLIC...08
Area Forecast Discussion...Updated
National Weather Service Saint Louis MO
922 PM CST Thu Jan 2 2020 .UPDATE... Issued at 910 PM CST Thu Jan 2 2020 Rain seems to be having a lot of difficulty building to the north into east central Missouri and central Illinois this evening. The last few runs of the RAP have been showing some weak moisture convergence ahead of the 850mb front this evening mainly over southeast Missouri into southwest Illinois. The RAP prints out correspondingly light QPF across parts of the eastern Ozarks into Randolph, Washington, and Marion counties in Illinois. This agrees well with the new NAM which is rolling in, as well as the hi-res CAMS. Have therefore backed off PoPs in most areas except the aforementioned eastern Ozark and southwest/southern Illinois counties. Carney && .SHORT TERM... (Through Saturday) Issued at 156 PM CST Thu Jan 2 2020 Split flow upper air pattern across North America features a deep trof centered across the Southern Plains into Mexico with a pair of northern disturbances across Ontario and Alberta. Model guidance is adamant that the southern stream shortwave and the northern disturbance over Alberta will phase into a closed upper low across the mid-Mississippi River Valley late Friday night into early Saturday morning. The greatest probability of measurable precipitation this evening will remain across the southeastern half of the CWA (south of I-44 in MO and east of I-55 in Illinois). Even here, the amounts will remain light with a tenth or two of an inch possible. The rain chances decrease even further after midnight as the shortwave instigating this precipitation quickly moves east of the area. Meanwhile, the cold front located just to our northwest will make steady progress through the CWA tonight with a wind shift to the north-northwest. This will lead to a cooler day on Friday with temperatures steady in the 40s. Another round of light rain Friday afternoon across southeast MO and southern IL is likely as the main southern shortwave approaches. Otherwise, it should be a dry day for locations north of I-44 in MO and west of I-55 in IL. The track of the northern disturbance and its evolution into a closed upper level low overhead Friday night and Saturday morning keeps chance PoPs for snow in the forecast across eastern Missouri and Illinois. A minor snow accumulation up to an inch remains possible. Temperatures will remain seasonably cold on Saturday with highs in the 30s. CVKING .LONG TERM... (Sunday through Next Thursday) Issued at 156 PM CST Thu Jan 2 2020 The upper air pattern remains quite active next week as a series of storm systems crash into the Pacific northwest, move across the Rockies and into the central CONUS. While the details of these systems are far from set in stone, the GEFS and ECMWF EPS ensemble mean suggests two systems will have the potential to bring sensible weather to our area next week. The first disturbance arrives from the northwest Monday night/Tuesday and looks to be moisture starved. Will need to monitor this though, as temperature profile would support snow. A much broader trof approaches the area from the west late in the week and will bring the best potential for widespread rainfall Thursday night and Friday. Temperatures will fluctuate some day to day, but overall remain above normal for the period with highs in the 40s/50s and lows in the 20s/30s. CVKING && .AVIATION... (For the 00z TAFs through 00z Friday Evening) Issued at 547 PM CST Thu Jan 2 2020 The primary weather concern for aviation interests tonight into Friday will be MVFR and IFR ceilings overspreading most of the area through tonight. IFR looks to be confined mostly to the eastern Ozarks and southern Illinois where intermittent light rain is also likely...but most of the area should be dropping to MVFR from late evening into the early overnight period. Once the ceilings go down it should stay low and drop below 2000 feet in most locations by 12Z or shortly thereafter. SPECIFICS FOR KSTL: Timing on when ceilings will drop to MVFR is moderate to low confidence at this time. Most guidance suggests between 04Z-07Z which is why I forecast the lowering ceiling at 05Z in the TAF. While most guidance keeps IFR to the south-southeast of the terminal, it looks like it will be very close...perhaps within 10-20NM of the terminal. At any rate, ceilings should drop to low MVFR between 12-14Z friday and stay low through the day. Carney && .LSX WATCHES/WARNINGS/ADVISORIES... MO...None. IL...None. && $$ WFO LSX
Area Forecast Discussion
National Weather Service Newport/Morehead City NC
932 PM EST Thu Jan 2 2020 .SYNOPSIS... High pressure will continue to ridge in from offshore through tomorrow, as a cold front will approaches from the west late in the day. The front will cross the region Saturday, and high pressure will build in from the west Sunday through early next week. && .NEAR TERM /UNTIL 7 AM FRIDAY MORNING/... As of 930 PM Thurs...A few isentropically-lifted showers are sneaking across southern portions of the CWA this evening with a few sites reporting brief periods of rain, despite a shallow but very dry surface-900mb layer per the 00Z MHX sounding. Added slight chance PoPs for a few hours based on RAP and HRRR guidance which is handling the activity reasonably. Other change is to lower dewpoints across the coastal plain as moisture has not advected as quickly into the area as first anticipated. Prev disc...Southerly flow will persist and strengthen tonight with high pressure remaining offshore. As a low pressure system forms over the Deep South, high clouds will continue to move across the area, with some occasional sprinkles or light showers possible, mostly across the coastal plain and around the Albemarle Sound. Low temps are expected around midnight with temps increasing towards morning especially close to the coast as winds increase. Have lows ranging from the low to upper 50s early, and then rising to the upper 50s to low 60s by tomorrow morning. && .SHORT TERM /7 AM FRIDAY MORNING THROUGH 6 PM FRIDAY/... As of 240 PM Thurs...Ahead of the next storm system, record breaking temperatures are expected despite a mix of sun and clouds. Temperatures will start off very mild in the 60s, and with very high low level heights, expect temps to reach the mid to upper 70s across most of the area...slightly cooler along the coastline, with readings remaining in the upper 60s to low 70s. Wouldn`t be surprised to see 80 degree readings in a few places where the most sunshine is seen. As low pressure moves up the southern Appalachians, a cold front will begin to push into the region, which will lead to chances for showers later in the day. Chances will be highest across the coastal plain, with scattered showers making their way to the coast by evening. && .LONG TERM /FRIDAY NIGHT THROUGH THURSDAY/... As of 300 PM Thurs...Unsettled weather will continue Saturday as a cold front crosses the area. Then, cooler and drier conditions expected Sunday into early next week as high pres dominates. Friday Night through Saturday...Better lift and moisture arrive late Friday night through Saturday morning, and have PoPs likely to categorical ahead of the cold front. After the front moves through Saturday, some post frontal showers are possible, especially over the northern half of the region, and have increased PoPs going into Saturday night. Temps will be very mild Friday night and into Saturday, mostly in the 60s and low 70s, but then will fall quickly behind the front Saturday night. Saturday Night through Wed...As upr trf crosses Sat night have slight pop in for good chunk of the area thru the evening then clearing late at night as drier air pushes in. High pres will build across Sun and Mon then slide offshore Tue with dry weather expected. Cold front with limited moisture will quickly cross Tue night with very little rain expected and have just slight pop. High pres builds back in from the W Wed. Temps return to closer to normal this period with highs mainly in the 50s and lows in the 30s inland to lower 40s coast. && .AVIATION /03Z FRIDAY THROUGH TUESDAY/... Short Term /through Tomorrow Afternoon/... As of 700 PM Thurs...High confidence in VFR conditions through tonight with sub-VFR conditions increasingly likely late Friday as rain chances increase. High clouds will continue overhead tonight with increasing mid-level clouds and a more scattered low-level deck tomorrow morning. LLWS expected overnight with lighter winds at the surface before threat diminishes somewhat with better mixing during the day. Long Term /Friday Night through Tuesday/... As of 230 AM Thu...Mainly dry weather and VFR Fri in warm sector with breezy SW winds. Better coverage of more substantial showers Friday night and Saturday along and ahead of a cold front with periods of sub VFR likely. Conditions shld improve to VFR late Sat as drier air spread in behind front. VFR will cont rest of the period as skies become mclr with high pres. Gusty W winds expected overnight Sat and into Sunday behind the cold front. && .MARINE... Short Term /Through Tomorrow/... As of 315 PM Thurs...Winds will be light this evening, and then increase to SW 10-20 kts through the night. Ahead of a cold front winds increase to 20-25 kts tomorrow. Seas are currently 1-3 ft and will hold steady through tomorrow morning when seas increase to 4-7 ft, and then further to 5-10 ft by late tomorrow afternoon. Have issued a SCA for the northern waters, effective tomorrow morning, and still have SCA`s for remaining coastal waters beginning around the same time tomorrow. Long Term /Friday Night through Tuesday/... As of 320 PM Thurs...Strong SW winds 20-30 kts will continue through Saturday afternoon, when a winds briefly relax behind the initial cold front. Then late Saturday night, winds increase behind another boundary, becoming W 25-35 kts with gusts to 45 kts possible through Sunday afternoon, with a Gale Watch likely needed for this period. Seas will peak Sunday at 7-12 ft. WNW winds decrease to 15 to 25 kt Sun aftn and grad diminish to less than 15 kt Mon as high pres builds in. Seas will build to 6 to 8 ft late Friday and peak 8 to 12 ft outer wtrs Fri night into early Sunday. Seas will drop to 4 to 6 feet by Sunday evening and cont to subside to 2 to 3 ft Mon. && .TIDES/COASTAL FLOODING... As of 330 PM Thu...Strong post frontal W winds of 25 to 35 kt with higher gusts Sat night into early Sunday will bring threat of minor sound side coastal flooding to the Outer Banks. && .CLIMATE... Record High Temps for 01/03 (Friday) LOCATION TEMP/YEAR New Bern 77/2000 (KEWN ASOS) Cape Hatteras 71/1966 (KHSE ASOS) Greenville 76/2000 (COOP - Not KPGV AWOS) Morehead City 72/2000 (COOP - Not KMRH ASOS) Kinston 75/2000 (COOP - Not KISO AWOS) Jacksonville 75/2000 (KNCA ASOS) && .MHX WATCHES/WARNINGS/ADVISORIES... NC...None. MARINE...Small Craft Advisory from 3 AM Friday to 7 PM EST Sunday for AMZ152-154-156-158. Small Craft Advisory from 8 AM Friday to 2 AM EST Saturday for AMZ150. && $$ SYNOPSIS...MHX NEAR TERM...SGK/MS SHORT TERM...SGK LONG TERM...RF/SGK AVIATION...RF/MS MARINE...RF/SGK TIDES/COASTAL FLOODING...MHX CLIMATE...MHX
Area Forecast Discussion
National Weather Service Marquette MI
651 PM EST Thu Jan 2 2020 .SHORT TERM...(This evening through Friday) Issued at 352 PM EST THU JAN 2 2020 WV imagery and RAP analysis indicated a northern stream mid/upper level trough from northwest Ontario through northwest MN to eastern Nebraska. One weak shrtwv supporting some light rain showers or spinkles was exiting eastern Upper Michigan while another was moving through northeast MN with little more than a few flurries. At the surface, a cold front extended through western Lake Superior into nw WI from low pressure near CYGQ, north of Lake Superior. Colder air was gradually moving into the west along with gusty westerly winds. Tonight, as 850 mb CAA drops temps from around -6C to -10C, expect some light lake and terrain enhanced pcpn to develop for w to wnw flow favored locations over the west and northeast. Since the moisture depth will be marginal for ice nuclei, expect a mix of fzdz and snow with some potential for minor glazing. Otherwise, expect low temps ranging from around 20 west to the mid and upper 20s east. Friday, winds will veer slightly to the nw with some lake effect pcpn still possible, mainly in the morning. Temps at or slightly above seasonal averages will prevail with highs in the upper 20s to around 30. .LONG TERM...(Friday night through Thursday) Issued at 440 PM EST THU JAN 2 2020 A progressive pattern will continue for us in Upper Michigan as a series of ridges and troughs traverse across the CONUS. The UP will remain dry Saturday as a shortwave digs into the central CONUS to the south of the UP. That shortwave will congeal with another wave, bringing widespread rain across the east and thunderstorms across the far southeast CONUS. Heading into Sunday, a clipper shortwave will drop south from Canada and will kick off some -SN from west to east in the early afternoon. Behind this wave, 850 temps fall to around -10C with the deterministic GFS falling much colder almost to -20C by Monday morning. Model differences start to appear into Monday morning, with more info on that below. In the extended, deterministic and ensemble model forecasts continue to hint at a large ridge building (as seen by 500mb height anomalies) across the N Pacific in the middle of next week. As this ridge forms, troughing will occur downstream in the western CONUS, which will shift the storm track further south. At this point, deterministic forecasting is a flip of a coin...but there is a signal for the southeast portions of the CONUS to see increased precipitation amounts as Upper Michigan remains on the safer side of any big blasts of cold air. As low pressure systems form along this storm track, the UP could see an increase in LES at times depending on track of storm and wind pattern...time will tell. Starting off on Friday night, a quick passing shortwave will pass just to the south of Upper Michigan as 850mb temps fall to 6C to - 8C. These temperatures are cool enough to get some LES, but sounding profiles suggest moisture is rather shallow with lack of DGZ saturation. Have included some slight chances for -SHSN and -FZDZ though with the additional support from passing shortwave...mainly downwind and along Lake Superior. Behind this shortwave, heights begin to rise through the day Saturday, with forcing and moisture limited should remain dry across the UP. The next chance for precipitation then comes late Saturday night into Sunday as a clipper shortwave approaches Upper Michigan from Canada. As the shortwave gets closer, it becomes negatively tilted with a sfc low developing and crossing Lake Superior Sunday afternoon. Out ahead of the trough axis, WAA and isentropic ascent will increase across Upper Michigan, which should be the engine for much of the snow development. Behind the wave, model 850 temps begin to diverge, leading to a bit of uncertainty on lingering LES chances. GFS gets rather cold almost to -20C while GEFS mean remains in the low teens blo zero. EC and GEM fall to near -10C through Monday before ridging and increases heights bring warming 850 temps by Monday night, cutting off any LES chances. GEM/EC then show another trough pushing through Tuesday morning, with cooling temps aloft bringing back some LES chances again. GFS keeps the potential for LES during the entire duration. A ridge of high pressure then moves into the Central Plains on Wednesday afternoon as winds back to the SW Wednesday night, cutting off any LES chances. Late into next week, ridging across the Pacific builds and will drive troughing across the western CONUS. This will push the storm track further to the south which should create some interesting weather for some across the eastern half of the CONUS depending on where exactly this features lies as shortwaves propagate through. && .AVIATION...(For the 00Z TAFS through 00Z Friday evening) Issued at 648 PM EST THU JAN 2 2020 MVFR cigs are expected to prevail at all terminals through the period. Westerly upslope flow into KCMX may result in some light snow showers or freezing drizzle. Otherwise, dry conditions are expected at KIWD and KSAW. && .MARINE...(For the 4 PM Lake Superior forecast issuance) Issued at 352 PM EST THU JAN 2 2020 Tonight, winds veers northwesterly between 20 and 30 knots, with the strongest winds shifting over south central and eastern parts of the lake. Through Friday, winds relax to less than 20 knots from west to east as surface ridging starts to move into the region. Expect winds to then remain below 20 knots through early Sunday morning. Attention then shifts to a clipper system that is progged to track over northern parts of the lake, remaining mostly in Canada. On Sunday, southwest to west winds will increase to 20 knots, further increasing to 25 to 30 knots Sunday night into Monday as winds become west-northwest behind the system. While models were in reasonable agreement with the track/timing of this system confidence is still low as to whether or not we will see any gales at this point. && .MQT WATCHES/WARNINGS/ADVISORIES... Upper Michigan... None. Lake Superior... None. Lake Michigan... None. && $$ SHORT TERM...JLB LONG TERM...JAW AVIATION...Voss MARINE...JLB