Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 04/08/22

Area Forecast Discussion
National Weather Service Boston/Norton MA
1020 PM EDT Thu Apr 7 2022 .SYNOPSIS... Low pressure moves up the eastern seaboard tonight, with rain heavy at times overnight along with a few thunderstorms possible. Behind the departing low, Friday should feature mainly dry and mild weather. Trending cooler over the weekend, especially Sunday. Scattered showers are expected Sat morning, followed by a drying in the afternoon. Drier, cooler and breezy Sunday, but can`t rule out a few brief afternoon showers, certainly not a washout. Next week will feature a warming trend but also a few episodes of showers are possible from time to time. && .NEAR TERM /UNTIL 6 AM FRIDAY MORNING/... 1015 PM Update: Tweaked PoPs, Wx and QPF a bit, focusing most of the heavier rains through 06z from Worcester to Block Island westward, then preferentially east of this same area into the Boston-Providence corridor after 07z. As of this writing, currently intermittent light showers were evident across most of SNE. That will be changing in a more substantial way as heavy rains and embedded thunderstorms now from the lower Hudson Valley down to just offshore of the DE coastline translate ENE to NE through the after-midnight period. This is associated with a frontal boundary and weak surface low near the Chesapeake Bay region with elevated PWAT values along and ahead of this feature, in a regime of strong moisture convergence. That cloud tops continue to cool with active lightning seen in GLM products asssociated with this area of precip certainly indicates convective processes continue despite the unfavorable time of day, and this is leading to efficient rain rates with a few LSRs from PHI/OKX in the northeast NJ area indicating some flooding. Think the HRRR has the best handle on timing of these heavier showers with embedded thunder into SNE, generally between 04-07z (midnight to 3 am) across interior MA/CT, and around 06-10z (2-6 am) into RI and much of eastern MA. Hydrologic response should be limited to rises on streams and creeks and urban/poor drainage type flooding, a part of which could intersect with the Friday morning commute across eastern MA and RI. It`s been a fairly breezy night as well with ESE winds around 25 to 35 mph. SE low level jet increases tonight and overnight to around 65 kt, and while speeds could increase about 5-10 mph in gusts, stable low-levels should keep us from gusts rising to level where wind headlines would need to be considered. Temps and dewpoints should continue to slowly rise overnight, with temps by daybreak in the upper 40s to lower 50s and dewpoints at similar levels. Previous discussion: Deep moisture continues to stream northward over eastern NY and southern New England this afternoon ahead of a digging trough over the entire eastern half of the U.S. This is evident on visible satellite where we see thick cloudcover over the northeast with more convective elements over PA into MD. The more robust and dynamic weather eventually makes its way into southern New England tonight bringing with it periods of heavy rain along with some lightning. Beneath said 500 mb trough the parent surface low spinning over the Great Lakes will strengthen a secondary low along the cold frontal boundary this evening which will move over southern New England tonight and into Maine by Friday night. Along with PWATs near 1.25" we`ll also have strong dynamics from a 50-60 kt low level jet centered over the Cape and islands which will help to squeeze a lot of moisture out of the atmosphere between now and 8 am Friday. Rainfall amounts will range from a quarter inch to an inch, locally higher, with the heaviest amounts over the high terrain of western MA and CT where east to southeast orographic flow will assist. These amounts don`t concern us with regard to any widespread flooding as they`re well below flash flood criteria. Also fortunate is the timing which brings the heavy rain in late tonight and pushes it out before the Friday morning commute. The southeasterly onshore flow will also help to cap things, with a stout inversion in the low levels keeping winds, while gusty, below advisory criteria. As the low moves overhead it will bring the warm sector into our area which means a few things; one, that we`ll have a non-diurnal temperature swing tonight with temperatures surging up into the low 50s for many toward sunrise Friday. This also introduces some elevated instability into the forecast overnight, with CAPE values of several hundred J/kg focused first over CT then shifting into RI and southeast MA. Fortunately with the strong inversion in place this will all be elevated in nature. && .SHORT TERM /6 AM FRIDAY MORNING THROUGH FRIDAY NIGHT/... Things will be significantly drier on Friday behind the cold front; PWATs below 0.50" with surface dewpoints dropping from the 50s back into the 30s or 40s. We`ll see significant clearing after 8 am with perhaps some diurnal clouds in the afternoon, especially for areas farther north where moisture lingers at 850 mb. Winds back out of the southwest for a very mild day, in the mid 60s! Friday night the broad trough overhead sends another shortwave through the flow overhead kicking off another round of light showers as a weak surface low passes overhead. Guidance has slowed a bit so the best chance of these showers looks to be toward the latter half of the night or early Saturday. Low temperatures bottom out in the 40s, save for the high terrain which may not make it out of the upper 30s. && .LONG TERM /SATURDAY THROUGH THURSDAY/... Highlights... * Scattered showers Sat morning, then dry for the afternoon * A few afternoon showers possible Sunday & cooler, but not a washout * A warming trend next week, but a few chances for showers too Precipitation... Lots of short waves rotating through high amplitude mid/upper level trough over the eastern Great Lakes and OH valley this weekend. One of these impulses moves across SNE Sat morning, with ample forcing for ascent and mid level moisture to yield scattered showers Sat morning, especially across the interior. As previous forecaster noted, cold air aloft may provide enough instability for a few thunderstorms across the interior Sat morning. Fast flow aloft, so behind the departing wave, a drying trend for Sat afternoon along with increasing sunshine. Drier Sunday, but -30C cold pool at 500 mb along with cyclonic flow will result in increasing diurnal clouds from late morning into the afternoon, along with isolated shower threat. By no means a washout, with most of Sunday being dry. High amplitude trough finally moves offshore by Monday, with dry weather and plenty of sunshine. Next chance of rain, sometime Monday night/early Tue with mid level warm front and airmass change to milder weather and not as dry, with dew pts rising from the 20s Monday to the 40s Tuesday. Then some uncertainty Wed/Thu, with potential for backdoor front Wed, possibly returning northward as warm front Thu. Just unable to resolve these smaller scale details at days 6-7. Temperatures... Still mild Saturday with core of the cool air remaining west of New England. Highs Saturday should climb into the upper 50s and lower 60s. Normal high for this time of year is low to mid 50s. A bit breezy Sat afternoon with WSW winds 15-25 mph, but mild temps and increasing afternoon sunshine will yield pleasant weather by early/mid April standards. Cooler and breezy Sunday as core of cold air aloft (-30C at 500 mb) is centered over SNE. Although, seasonably cool with highs in the 50s. Morning sunshine gives way to lots of afternoon clouds, given cold air aloft and cyclonic flow. Core of cold air aloft finally moves offshore, thus setting the stage for a nice day Monday, with highs in the upper 50s and lower 60s. Breezy and cool in the morning, but high pressure advecting into SNE, winds should diminish Mon afternoon. Change in airmass Tuesday with east coast ridge. Thus trend toward warmer temperatures, but lots of uncertainty regarding the strength of northern stream energy climbing over this ridge and possibly delivering a backdoor front and a cooler airmass around Wed. This front may lift back north Thu, with a return to warmer weather, but again difficult to nail down these details at days 6-7. While it fits climatology, overnight temps the next 7 days likely remain above freezing across most of the region. && .AVIATION /02Z FRIDAY THROUGH TUESDAY/... Low - less than 30 percent. Medium - 30 to 60 percent. High - greater than 60 percent. 00Z TAF Update: broken line of heavy showers and embedded thunderstorms expected to move across CT/RI/MA between 06z-09z from southwest to northeast, exiting Cape Cod around 11z Fri. Earlier discussion below. ================================================================= Today: Moderate confidence. Generally SCT-OVC VFR and MVFR today, lowering to IFR from southwest to northeast late afternoon. Should be generally dry with a better chance for showers BDL- BAF after 00z. E/ESE winds will be 10-15 kt, with gusts 20-25 kt. Tonight: Moderate confidence. Generally MVFR/IFR with improvement behind the cold front. Ahead of the front a line of showers and thunderstorms will bring periods of heavy rain between 03 and 10Z. Confidence in the occurrence and timing of thunder is moderate. Heavy rain may reduce visibility to IFR for a time. SE low level jet of 45 to 55 kt will cause SE gusts to increase to 25-30 kt from the SE. Friday: High confidence. VFR. Mostly dry weather after 14Z. Winds become SW 5-10 kt, gusts 18-20 kt across Cape Cod and Islands. Friday night: High confidence. Mainly VFR with local MVFR possible in scattered rain showers after 08Z. Light S winds. KBOS TAF...Moderate confidence in TAF. KBDL TAF...Moderate confidence in TAF. Outlook /Saturday through Tuesday/... Saturday: Mainly VFR, with areas MVFR possible. Breezy. Chance SHRA. Saturday Night: VFR. Breezy. Sunday: Mainly VFR, with local MVFR possible. Breezy. Slight chance SHRA. Sunday Night through Monday: VFR. Breezy. Monday Night: Mainly VFR, with local MVFR possible. Tuesday: Mainly VFR, with local MVFR possible. Breezy. Slight chance SHRA. && .MARINE... Forecaster Confidence Levels. Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent. A southeast low level jet of 65 kt kicks up this evening bringing SE gusts to 35 kt tonight, with up to 40 kt across the eastern waters. Seas will increase overnight to as much as 15 ft near the northeast MA coast with 7-10 ft seas across the southern waters. We will see potential for thunderstorms on the waters during the overnight hours, with visibility briefly reduced to as low as one mile at times. Gale warnings will need to be converted to SCAs into Friday with winds becoming SW and decreasing through Friday night. Outlook /Saturday through Tuesday/... Saturday: Winds less than 25 kt. Seas up to 5 ft. Slight chance of rain showers. Saturday Night: Winds less than 25 kt. Local rough seas. Sunday: Winds less than 25 kt. Seas up to 5 ft. Sunday Night: Low risk for Small Craft Advisory winds with gusts up to 25 kt. Local rough seas. Monday: Winds less than 25 kt. Local rough seas. Monday Night: Winds less than 25 kt. Seas locally approaching 5 ft. Tuesday: Winds less than 25 kt. Slight chance of rain showers. && .BOX WATCHES/WARNINGS/ADVISORIES... CT...None. MA...None. RI...None. MARINE...Gale Warning until 8 AM EDT Friday for ANZ230>232-251-255. Gale Warning until 4 AM EDT Friday for ANZ233>237-256. Gale Warning until noon EDT Friday for ANZ250-254. && $$ SYNOPSIS...Nocera/BW NEAR TERM...Nocera/Loconto/BW SHORT TERM...BW LONG TERM...Nocera AVIATION...Nocera/Loconto/BW MARINE...Nocera/Loconto/BW
Area Forecast Discussion
National Weather Service Burlington VT
1029 PM EDT Thu Apr 7 2022 .SYNOPSIS... Occasional rain with embedded heavier downpours will continue across the North Country tonight, along with gusty southeast downslope winds along the Western Slopes. A few gusts in the 50 to 55 mph range are expected this evening, which may cause isolated power outages. Drier weather returns for Friday, with temperatures warming back into the mid 40s to lower 50s, before better chances for showers redevelop again on Saturday with cooler temperatures. && .NEAR TERM /THROUGH FRIDAY NIGHT/... As of 1028 PM EDT Thursday...Overnight forecast continues to work out well with several sites along the western slopes now gusting to 50 mph as precipitation has briefly waned as the 850mb jet aloft materialized. Adjusted PoPs and wind gusts for the next few hours to match trends, otherwise the forecast remains on track. Previous Discussion...Fcst concerns tonight wl be gusty southeast downslope winds and timing of rain with embedded heavier downpours. Big picture shows deep and closed 5h/7h circulation over the western Great Lakes, while potent 5h vort is aiding weak 1001mb low pres over SE VA this aftn. This energy which has produced some lightning acrs south-central PA wl interact with developing robust southeast llvl jet to produce a period of moderate rainfall acrs the cwa tonight. Based on nose of se jet, pws near 1.0, and nose of 120 knot jet at 25h, expect eastern dacks and se upslope regions of the southern-central Greens wl receive the highest qpf with amounts 1.0 to 1.50, while downslope regions of the western slopes and NEK get 0.50 to 0.75 by Friday morning. Based on rainfall and trrn influence on qpf fields, Ausable River Basin wl need to be watched, otherwise just in bank rises anticipated on rivers/streams acrs our HSA. The magnitude of southeast downslope winds along the western slopes this evening is tricky based on anticipated precip fields and impacts of llvl mixing. Overall RAP/NAM/GFS and RGEM in all good agreement showing progged 850mb se jet of 60 to 70 knots developing over southern VT around 00z and lifting northward and thru our cwa by 06z. However, the depth of mixing associated with moist adiabatic mixing profiles in occasional rain makes it challenging. Crnt thinking a brief lull in rainfall is anticipated btwn 22z-04z from south to north and this combined with bottom of mixed layer winds of 40 to 55 knots, wl support localized gusts in the 45 to 55 mph range along the western slopes in Rutland and eastern Addison Counties. Sounding analysis at Rutland shows inversion height near 3500 ft, with mixed layer winds of near 50 knots at 22 to 00z this evening, supporting the advisory. If slightly more dry air develops with better mixing, wind gusts to 55 to 65 mph will be possible, but feel the probability of this occurring is low given radar coverage attm. Wl brief evening shift on this potential, as HRRR and RAP show stronger wind potential. Otherwise, for the central western slopes, jet is slightly higher up and top of the mixed layer is slightly less, so general idea of gusts to 40 to 50 mph acrs eastern Chittenden and parts of Lamoille Counties looks reasonable. Finally, lets not forget about the white stuff, which wl only occur near summit level and have no impacts acrs our cwa. Soundings show profiles becoming near isotherm around 0C this evening from 3000 feet and higher, especially eastern dacks, where se upslope flow enhances the cooling process. This thermal profile wl produce a period of wet snow when the heaviest precip occurs for the eastern dacks with a quick inch or two possible above 3000 feet by 12z Friday. Over VT thermal profiles show warm nose above 5000 feet of 3 to 4C air with llvl se jet, while pocket of air remains near 0C from 2500 to 4000 feet, supporting some mixed precip for the eastern slopes of the Greens. Only a minor glaze of ice accumulation possible on elevated sfcs above 2500 feet or so possible overnight. Temps range from near freezing summits to lower 40s warmer valleys. Friday, soundings show developing dry layer btwn 850-500mb which is supported by well defined drying on water vapor moving overhead. This wl decrease the areal coverage of precip by 15z, with just some scattered aftn showers. Best potential wl be southwest upslope regions of the High Peaks and portions of the northern/central Green Mtns. Temps with a few breaks in the overcast should warm into the mid 40s to lower 50s. && .SHORT TERM /SATURDAY THROUGH SATURDAY NIGHT/... As of 341 PM EDT Thursday...Showery weather will continue through the weekend as the North Country remains under the influence of the upper trough. Another embedded impulse will pass through the flow aloft on Saturday, producing a surface low across New England. As the upper trough axis draws closer, temperatures aloft will cool causing lapse rates to steepen and marginal instability to develop. Meanwhile, a cold front will trek across the region. Together this will result in the development of scattered to numerous rain showers, with the possibility of isolated thunderstorms across south-central Vermont during the afternoon. Some locations may even see a bit of graupel. Westerly flow will become established in the wake of the boundary and cooling aloft will result in a mix of rain/snow showers for locations above 1500 ft elevation by Saturday night. However, the areal coverage of showers will decrease late Saturday into Sunday as a weak nose of high pressure sneaks into the area. High temperatures on Saturday will be in the mid 40s to low 50s with overnight lows in the low to mid 30s. && .LONG TERM /SUNDAY THROUGH THURSDAY/... As of 341 PM EDT Thursday...Dreary, cool weather continues for Sunday as the main trough axis finally moves through the Northeast. As it does so, we will see yet another cold front traverse the North Country. This will initiate renewed chances for scattered rain and mountain snow showers, especially along the northern slopes of the Adirondacks and northern Green Mountains as flow becomes northwesterly. Northwest winds will increase up to 10-15 mph with gusts up to 25 mph. High temperatures will only be in the low to mid 40s making for an overall yucky day weather wise. Given the cooler surface temperatures on Sunday, there exists very little chance of thunder, though again a bit of graupel cannot be ruled out. Dry weather is then expected for Monday as high pressure settles across the region. Temperatures will start out chilly with morning lows in the mid 20s to mid 30s, though daytime highs will reach into the 50s aided by filtered sunshine. A gradual warming trend is expected thereafter under a regime of westerly/southwesterly return flow. High temperatures during mid-week will be in the 60s with overnight lows in the 40s. Chances for periodic rain showers and an occasional thunderstorm exist as moisture rolls around the top of the upper ridge, especially Tuesday into Wednesday. However, timing differences remain among global model guidance. By the end of the week, there exists increasing chances for widespread precipitation as a full-amplitude trough approaches the East. && .AVIATION /03Z FRIDAY THROUGH TUESDAY/... Through 00Z Saturday...Mix of VFR/MVFR across the region currently will deteriorate to IFR/MVFR mainly after 06Z with the main contributer being ceilings. In widespread rain through around 12Z, visibility will mainly be VFR/MVFR with brief periods of IFR possible. Thereafter conditions will gradually improve, though remaining at least MVFR through 18Z and trending VFR by 22Z. For all sites except KRUT and KMPV winds will generally be less than 10kts though briefly gusty at KBTV this evening. Otherwise, southeast winds will continue to ramp up substantially at KRUT where gusts in excess of 40kt will be possible through the early overnight period. At KMPV gusts ramp up as well, but should only peak in the 20-30kt range through midnight. LLWS and turbulence aloft associated with 40-60kts at mountain top levels is additionally likely through 12Z Friday. Equipment note: AMD NOT SKED continues for MPV TAF owing to a communications issue, with a tech expected on-sote Monday 04/11. MSS lost observations at 17Z on 4/7, so AMD NOT SKED there as well for the time being. Outlook... Friday Night: VFR. Chance SHRA. Saturday: Mainly MVFR, with areas VFR possible. Numerous SHRA. Saturday Night: Mainly VFR, with areas MVFR possible. Scattered SHRA, Chance SHSN. Sunday: Mainly MVFR, with areas VFR possible. Chance SHRA. Sunday Night: Mainly VFR, with areas MVFR possible. Slight chance SHRA. Monday: Mainly VFR, with areas MVFR possible. NO SIG WX. Monday Night: VFR. Slight chance SHRA. Tuesday: Mainly MVFR, with areas VFR possible. Slight chance SHRA. && .HYDROLOGY... Rainfall has ranged from 0.25 to 0.50 across northern NY today with isolated higher amounts near 0.75, while VT has seen amounts <0.25. Additional widespread rainfall is anticipated overnight with another 0.50 to 1.0 expected, producing 24 hour storm totals of 0.5 to 1.75 inches, with localized higher amounts up to 2 inches possible. This rainfall will cause sharp rises on area rivers and streams, with the Ausable River expected to approach action stage by Friday. && .BTV WATCHES/WARNINGS/ADVISORIES... VT...Wind Advisory until 6 AM EDT Friday for VTZ006-011-017>019. NY...None. && $$ SYNOPSIS...Taber NEAR TERM...Lahiff/Taber SHORT TERM...Hammond LONG TERM...Hammond AVIATION...Lahiff HYDROLOGY...Taber
Area Forecast Discussion
National Weather Service Indianapolis IN
1129 PM EDT Thu Apr 7 2022 ...Updated Aviation Discussion... .Forecast Update... Issued at 958 PM EDT Thu Apr 7 2022 Surface Analysis this evening shows deep low pressure in place over eastern WI. The low was spreading its influence with cyclonic flow across the Great Lakes...Upper midwest and the Ohio valley. GOES16 shows a classic pinwheel cloud formation across the region...with another spoke over Central IL...poised to push across Central Indiana overnight. With the loss of heating...diurnal showers have ended and some of the lower level stratocu has also dissipated. Cold air advection was 850mb temps of -6 to -8 were being pushed toward Central Indiana. Overnight the cyclonic flow is expected to remain across the region as the cut-off low makes little progress eastward. The previously mentioned trough within the flow is expected to push across Central Indiana late overnight...thus have ramped up pops late overnight as this forcing feature passes. Any precip amounts should remain light. Given the expected increasing clouds and possible precip trended toward nearly steady state temps as temperatures upstream were quite similar to current conditions. && .Short Term...(This evening through Friday night) Issued at 241 PM EDT Thu Apr 7 2022 ...Gusty winds today with scattered showers... ...Chance of snow Friday into Saturday... Overview A deep trough and associated stacked low pressure system currently resides over the region. The slow-moving trough is expected to keep temperatures below average for the next several days. Cold air advection aloft will continue through the period, with 850 mb temps bottoming out around -10 C by 12z Saturday. A mix or even a changeover to snow is possible by Friday night and Saturday. Today into Tonight Today started out clear to partly cloudy across much of the area, but clouded over as daytime heating quickly steepened lapse rates. The unstable air has had two main effects so far: scattered showers and gusty winds. Momentum aloft has been easily transported downward leading to frequent wind gusts of 25 to 35 kts. Gusty conditions should continue until sunset, only diminishing once some stability returns. As the core of the stacked low gets closer, winds aloft should decrease a bit. So not currently expecting as windy of a day for Friday. Rain showers have also developed and are fairly widespread across the state. These should continue into tonight, though the aforementioned loss of instability will lead to a decrease in coverage. However, shower chances will not completely diminish, and we`ve kept slight to chance PoPs across portions of the CWA. Some snowflakes could mix in tonight as well, since cold air continues to filter in aloft. Friday into Saturday Similar situation for Friday, with a cold unstable air mass overhead. Scattered rain / snow showers and occasional wind gusts to 20 kts will be possible at times. Day time heating should once again steepen lapse rates Friday afternoon leading to a convective precip regime. An isolated rumble of thunder is possible within the more robust showers that develop. Conditions should be warm enough to allow predominately rain during the day time hours, though some snow may mix in at times. However, after sunset, temperature profiles quickly cool and a changeover to snow is shown in the hi-res models. Concurrently, a vort max rotating around the main area of low pressure will work its way into Indiana from the northwest. An enhanced area of precipitation is shown by various models in response to weak forcing associated with this feature. At the moment, timing appears to be early Saturday morning, towards the end of the short term period. A quick coating of snow on grassy surfaces is certainly possible, especially in the northern counties and if precip occurs before sunrise. && .Long Term...(Saturday through Thursday) Issued at 241 PM EDT Thu Apr 7 2022 HEADLINES * Quite chilly Saturday, warming trend begins Sunday afternoon * Temps at or above normal much of next week * Episodic showers and storms possible early next week * Strong/severe storm potential mid next week DETAILS * Saturday... A significant weather pattern change will occur from this weekend into next week. The deep, winter-like trough aloft across the OH Valley and Great Lakes will finally begin to lift ENE on Saturday. However, residual morning light snow or snow grains may still occur as model soundings advertise a saturated air column at or below freezing. A coating of snow from overnight Friday night should remain mainly on grassy areas and elevated surfaces Saturday morning, as road temps generally remain above freezing. Any leftover precip will end during the day as the trough pull outs, although clouds should remain (maybe some late day clearing west) which will make for another chilly early spring day, with high temps only in the 40s. The morning coating of snow will melt during the day. * Saturday night... Surface high pressure will build into the OH Valley Saturday night in the wake of the departing system. As a result, skies will clear and surface temps will fall as effective radiational cooling commences. Expect low temps Sunday morning to reach around 30, will some areas (especially valleys/sheltered locations) in the upper 20s. Coupled with weak surface winds, a widespread frost should occur with a light freeze in areas. With sufficient vegetation growth already across our southern counties of central IN, headlines for frost and/or freeze may be needed in later forecasts across about the southern two rows of counties, i.e., along/south of Sullivan to Bloomington to Columbus to Greensburg. Farther north in central IN, vegetation may not yet be enough for headlines, but frost/freeze awareness is still needed. We will evaluate later data as we approach Saturday night. * Sunday... As a high pressure ridge aloft builds into the OH Valley, the surface high will quickly move off to our east, allowing a return S to SW low-level flow to commence with an influx of milder air. At the same time, the warm advection also means some isentropic lift and some clouds in the afternoon, which could limit diurnal warming a bit after a cold start, but still enough sunshine to warm afternoon highs to 55-60 northeast and 60-65 southwest parts of central IN. * Sunday night through Tuesday... As a broad but deep trough aloft forms across the western CONUS early next week, S to SW flow aloft will result downstream across the nation`s midsection into OH Valley, with embedded pockets of shortwave energy ejecting out of the trough. This will provide periodic enhancement to northward moisture transport from the Gulf of Mexico to produce episodic convection across the central U.S. into parts of the OH Valley. As expected, some model differences occur which is not unusual in a transitory weather pattern with broad, fast SW flow aloft and embedded shortwaves. Thus, forecasting the timing and location of the greatest chances for precip, coverage, and intensity across our area at this time is somewhat tenuous, but expect both periods of rain and dry weather. With at least modest isentropic lift across the OH Valley Sunday night into early Monday, scattered showers may occur during this time period, although again there are some differences in forecast solutions. Model soundings do show some steepening of lapse rates aloft above a stable boundary layer, so a few elevated convective cells may occur as well, if showers materialize. Right now, solutions range from dry weather Monday night and early Tuesday with a frontal passage, to good rain chances along a stalling front. For now, given SW flow aloft, would not expect the front to make it too far south, and model blended forecasts show at least scattered showers during this time frame over central IN, which appears prudent for now. Additional scattered showers and elevated storms could occur later Tuesday as well, but any chance for organized severe storms during this forecast period should mainly remain S and W of central IN. Expect high temps Monday and Tuesday in the upper 60s and lower 70s. * Wednesday and Thursday... The middle part of next week is a long way off, but could be interesting. Guidance suggests a consensus signal for increasing convective potential and even a severe weather threat. Models generally show the western trough lifting to the NE into the central and northern Plains. As this occurs, it would create a strengthening low-level jet downstream in response to divergence aloft. Models hint at better instability as well along and ahead of the system`s associated cold front. Storms are possible over the OH Valley for at least part of Wednesday, with the best chance at strong to severe storms either late Wednesday or Thursday associated with a linear forced line of convection (QLCS) across the mid MS Valley and into the OH Valley. Uncertainly still exists, but awareness of this potential situation is important. && .Aviation...(06Z TAF Issuance) Issued at 1129 PM EDT Thu Apr 7 2022 IMPACTS: - Scattered rain showers return overnight, no vsby restrictions expected. - VFR CIGS expected to deteriorate to MVFR and possibly IFR overnight. DISCUSSION: Brief break in light rain showers is expected over the next 1-3 hours before the next weak trough pivoting around the low begins to push across Indiana. Forecast soundings overnight continue to show steep lapse rates with good saturation in place amid the cyclonic flow. Thus an isolated shower during the overnight hours cannot be ruled out. HRRR shows shower development late tonight and toward daybreak in the wake of the previously mentioned trough that is expected to pass. Thus have trended toward a return of MVFR Cigs overnight along with a VCSH mention for possible rain showers. IFR cigs will be possible. Once again on Friday afternoon...steep lapse rates remain in place with saturation and attainable convective temperatures...providing a good signal for another afternoon of instability showers...with a possible mix of graupel...rain and/or snow. have used a tempo group during peak heating hours to account for best chances for precip. && .IND WATCHES/WARNINGS/ADVISORIES... None. && $$ Update...Puma Short Term...Eckhoff Long Term...Funk Aviation...Puma
Area Forecast Discussion
National Weather Service Marquette MI
1145 PM EDT Thu Apr 7 2022 .SHORT TERM...(This evening through Friday) Issued at 449 PM EDT THU APR 7 2022 Water vapor imagery and RAP analysis show a large mid-level low centered over WI. At the sfc, associated low pres was located in ne WI. With the sfc thru mid-level low just s of the area, pcpn movement across Upper MI today is following the cyclonic flow around it, lifting n toward eastern Upper MI, then moving e to w across the central then curving to a nne to ssw direction across western Upper MI. Pcpn has been rain across central Upper MI and rain/snow across the w. High terrain of western Gogebic/Ontonagon counties has been all snow today. Although there has been steady -sn there, temps around 32F and Apr solar insolation, limited as it is thru the cloud deck, has resulted in roads/parking lots being mostly just wet per webcams. The snowfall rates have just not been great enough to overcome that. So, snow accumulation is occurring mainly on the ground and trees. Low-level winds have had just enough of an easterly component so far to minimize upsloping in western Upper MI. Across the stateline, particularly toward Ashland, steady, heavier snow has fallen thru the day. Fcst thru Fri will revolve around pcpn details, coverage/type, as center of aforementioned broad mid-level low drifts to northern Lake Huron. As it moves e, low-level cyclonic flow will back to a northerly direction tonight/Fri and air mass will cool further. The cooling will lead to pcpn changing over to all snow from w to e tonight, then daytime heating on Fri may result in a little -ra mixing back in across the s central and e. While the cooling air mass with 850mb temps dropping to -8 to -10C later tonight/Fri will add a modest lake component to the pcpn, upsloping will be the prime driver of steadier/heavier pcpn. All of the cams have a very distinct signal of max pcpn aligned right on the high terrain just inland from the lake across the w and toward the n central where northerly wind upsloping is maximized. That looks right on track with what would be expected for this type of event. So, the greatest snow amounts will be very localized to the high terrain areas favored by upsloping. Those areas roughly include Ironwood to the Porcupine Mountains to Bergland, around Twin Lakes, around Calumet, from Phoenix to Delaware and from just inland of L`anse to Herman and e across the high terrain of northern Marquette County to the north of M-28. In general, from this evening to early Fri aftn, expect 4-8 inches of wet/dense snow accumulation in the aforementioned areas with perhaps as much as isolated 10 inches. Snow accumulations will rapidly fall off away from those areas. Winter wx advys have been posted from Gogebic County thru the Keweenaw then east to Marquette County, but in reality, advy criteria snowfall will be limited in coverage across those counties. Advy currently only runs thru early Fri aftn with expectation of limited daytime heating working to limit aftn snow accumulation on roadways. Lows tonight will fall to 24 to 30F, coolest w. Highs on Fri will only top out around 30F w to the mid 30s s central and e. .LONG TERM...(Friday night through Thursday) Issued at 406 PM EDT THU APR 7 2022 The slow-moving, vertically stacked low keeps cool and damp weather going into Saturday. A warming and drying trend is expected late Saturday into early next week with precip chances increasing again toward the middle of next week. Starting with Friday night, orographic snow showers will be ongoing within nearly saturated north-northwest flow. Shower coverage and intensity wanes by sunrise on Saturday with most precip focused across the east half to two thirds. The east should stay mostly cloudy if not overcast all day whereas the west may become mostly sunny by the afternoon. Tried to warm daytime temps across the west by 1-2F and vice versa across the east. Sunday looks mostly sunny with good mixing beneath ridging at the surface and aloft. I nudged temps warmer with widespread upper 40s to lower 50s look like a good bet. The fly in the ointment is an afternoon lake breeze looks fairly likely so pinning down the diurnal temperature curve will be a challenge. The ridge axis shifts east on Monday as a deep upper level trough digs into the western CONUS. The western trough/eastern ridge pattern appears to stick around for most of next week resulting in a prolonged period of SW flow aloft and above normal temperatures. Precipitation chances are less clear, but a shortwave trough lifting northeast across MN on Monday may allow for some precip, mainly across the west. This system pushes a cold front to our eastern zones by Tuesday morning where it may stall until a much stronger mid-week system lifts northeast across the Plains. Ensemble means show a fairly deep surface low over KS on Wednesday morning that lifts northeast into the Upper Great Lakes by Thursday night. Most available guidance indicates rain will be the dominant p-type, but that is subject to change depending on the exact low track. && .AVIATION...(For the 06Z TAFS through 06Z Friday night) Issued at 1143 PM EDT THU APR 7 2022 Poor flying conditions expected for the duration of this TAF period as well as a low pressure system continues to rotate over the Great Lakes. Generally LIFR conditions with some fluctuation at times to IFR can be expected. Meanwhile, winds will generally be northerly with some gusts up to 22 to 24 kts at KIWD/KSAW. But, KCMX will experience stronger wind gusts up to 28 to 30 kts for a prolonged period. && .MARINE...(For the 4 PM Lake Superior forecast issuance) Issued at 406 PM EDT THU APR 7 2022 NNE gales around 35 kts continue over the western two thirds of Lake Superior this evening then back northerly as a low pressure system digs southward towards Lower MI. This low then lifts northeast into Canada on Friday with winds backing to the NNW and becoming 20 to 30 kts across the lake. NNW winds of 20 to 30 kts are expected to persist throughout Friday night, falling below 20 knots across the western lake. NW winds of 20 to 25 kts continue over the eastern lake on Saturday. Light winds of 20 kts or less are expected by Saturday night as surface ridging moves over the lake. The light winds of around 20 kts or less are expected to remain over Lake Superior until Sunday night. Southeast winds of 20 to 25 knots develop over the north-central lake Sunday night and gradually diminish by Monday evening. Winds stay below 20 knots Monday night through next Wednesday. && .MQT WATCHES/WARNINGS/ADVISORIES... Upper Michigan... Winter Weather Advisory until 2 PM EDT /1 PM CDT/ Friday for MIZ001>005-009. Lake Superior... Gale Warning until 1 AM EDT /midnight CDT/ Friday for LSZ162. Gale Warning until noon EDT Friday for LSZ264. Gale Warning until 11 AM EDT Friday for LSZ263. Lake Michigan... None. && $$ SHORT TERM...Rolfson LONG TERM...EK AVIATION...TDUD MARINE...EK
National Weather Service Raleigh NC
840 PM EDT Thu Apr 7 2022 .SYNOPSIS... A cold front will push east and off the North Carolina coast tonight. This will be followed by a second cold front passage through North Carolina Friday night through early Saturday. A cool ridge of high pressure will build over the East Coast late Saturday through Sunday, then a warm front will lift northward through the area Monday, bringing a return to warmer weather. && .NEAR TERM /THROUGH TONIGHT/... As of 840 PM Thursday... The surface low and trailing cold front have pushed into far eastern sections and are on pace to exit the forecast area in the next hour or so, in tandem with the departing high PW. A trough (actually an outflow) extending from the surface low WSW across the southern CWA will continue to drop southward as cooler/drier and more stable air builds in slowly from the NW and W. But the risk of showers will persist through tonight, mainly across the N half, as the large upper low over the Great Lakes eases eastward, resulting in prominent height falls over the Mid Atlantic through Carolinas along with a shot of DPVA as sheared vorticity swings NNE through the region, atop a weak surface frontal zone that will cross our area overnight. While mostly showers are expected, RAP forecast soundings depict fairly steep lapse rates and moistening up through 600 mb, including the mixed phase region, such that lightning is possible, particularly as the dynamic forcing for ascent couples with 100-200 J/kg of SBCAPE. But no additional strong storms are expected, as the 00z GSO sounding as well as RAP forecast soundings depict a strong warm/stable layer through the 500-400 mb depth. Otherwise, expect partly to mostly cloudy skies overnight as that moisture in the upper reaches of the deep mixed layer persists overnight with large scale lift. Expect lows in the 40s to around 50. -GIH && .SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/... As of 200 PM Thursday... The deep trough(2 to 3 S.D. before normal) currently centered over the Midwest/Great Lakes region will progress slowly eastward through the Eastern US through Saturday night. Coincident with several prominent spokes of shortwave energy diving SEwd through the mid- Atlantic region, through the base of the trough, central NC will see periodic flare-ups of enhance cloud bands along with isolated shower and/or sprinkles across the area late Friday afternoon/evening and again Saturday. Deep afternoon mixing to 8-10kft both days will support breezy conditions in the 20 to 30 mph Friday, 15 to 25 mph Saturday. After daytime highs in the 60s on Friday, expect unseasonably cool daytime highs 55 to 60, which is 10 to 15 degrees below normal. Behind a series of weak surface troughs/cold fronts traversing the region cool high pressure will begin to move east into the area Saturday night, at which time skies are also expected to finally clear out. Low-level thicknesses Sunday morning are expected to lower into the 1295-1300 meters, which would be supportive of min temps in the lower to mid 30s across portions of the western and central Piedmont and northern coastal plain counties. A Frost Advisory will likely be needed. && .LONG TERM /SUNDAY THROUGH THURSDAY/... As of 210 PM Thursday... Temperatures will quickly moderate early next week as the anomalously deep upper trough departs and upper-level ridging moves atop the region through the mid week period. Well above normal highs in the upper 70s to lower/mid 80s will return by Tuesday and will temps will remain well above normal until a cold frontal passage late Friday. Well removed from a strong/deep closed low and upper trough centered over the central/northern US Plains, rain chances will remain low with some scattered showers possible mainly across the far western zones late Wednesday and Thursday from glancing shots of weak upper level impulses moving through the region. && .AVIATION /00Z FRIDAY THROUGH TUESDAY/... As of 710 PM Thursday... There is high confidence that VFR conditions will start the TAF period. Some lingering showers/storms are still near RWI, but should quickly move out of this TAF site shortly before 01Z. Elsewhere, VFR conditions are expected through the 24-hour TAF period. Given that RWI has seen rainfall from storms today, as well as lingering low- level moisture, introduced a period of MVFR VIS prior to daybreak Fri for potential fog development. Gusty southwest winds between 25 and 30 kts will be present Fri afternoon and early evening at all terminals with a deep upper-trough over the region. The trough may produce some scattered showers/sprinkles at GSO/INT. Outlook: Gusty west winds are again possible Sat under some possible VFR showers/sprinkles. Otherwise, VFR conditions will prevail Sat through Tue. && .RAH WATCHES/WARNINGS/ADVISORIES... None. && $$ SYNOPSIS...Hartfield NEAR TERM...Hartfield SHORT TERM...CBL LONG TERM...CBL AVIATION...Kren
Area Forecast Discussion
National Weather Service Shreveport LA
948 PM CDT Thu Apr 7 2022 .UPDATE... After due consideration of several contributing factors, the existing minimum temperatures forecast for daybreak Friday morning continue to look reasonable enough to carry with this update. While temperatures have indeed dropped noticeably after sunset this evening and skies areawide are quite clear, sustained northwest winds in excess of 5 kts areawide through the night look to facilitate mixing sufficient to prevent unrestrained radiational cooling. The 01Z HRRR and RAP13 solutions suggested minimum temperatures equal to our existing minT grids, even a degree or two warmer at some sites. Thus, have elected to keep low temperatures for the Four State Region in the low to mid 40s, with a few upper 30s possible in southwest Arkansas, and locally warmer values in urban areas. Ingested the temperature and dewpoint observations from the last several hours and interpolated through the aforementioned lows at 12Z Friday. /26/ && .PREV DISCUSSION... /issued 626 PM CDT Thu Apr 7 2022/ AVIATION... For the 08/00Z TAFs, VFR vis/cigs will prevail throughout the course of this TAF period. The only complicating factor will be gusty northwest winds, with sustained speeds of 10 to 15 kts calming somewhat overnight to 4 to 8 kts with gusts of 10 to 15 kts still possible before becoming still gustier tomorrow, with speeds of 15 to 20 kts and gusts of 20 to 25 kts likely. /26/ PREV DISCUSSION... /issued 300 PM CDT Thu Apr 7 2022/ SHORT TERM.../Tonight through Friday Night/ Todays AFD could darn near just be a copy/paste from yesterday, as there really is no change in the pattern anticipated over the next 36 hours. Aloft, the region will remain under under a strong NW flow, which will continue the very try trend across the area. Winds will likely remain on the gusty side into tomorrow as well under a tight pressure gradient. However, they appear to look slightly weaker than today, and wind headlines may not be needed tomorrow. That decision will likely come with the overnight shift. Temperatures tonight and tomorrow night will very much be on the cooler side. Lows tonight should range in the low to mid- 40s, with lows tomorrow dropping into the mid-30s and low-40s. Given additional time in the cold regime, afternoon highs tomorrow look to be slightly cooler than today, with highs getting into the low to upper-60s area-wide. /44/ LONG TERM.../Saturday through Thursday/ Our streak of dry and pleasant weekends with active weather holding off until the workweek will remain intact during this long-term period. Sfc high pressure will dominate this weekend and together with an advancing upper level ridge, temperatures will moderate as southerly flow returns by late Saturday. This will result in a rapid warming trend through early next week as afternoon highs jump back into the 80s areawide from Sunday through Wednesday. However, this warming trend will come at a price as it often does this time of year as we enter the peak severe weather season of mid April. During the day on Monday, strong warm and moist air advection will precede a shortwave disturbance while a cold front remains well to the west over the Texas panhandle region. As the shortwave pivots into the eastern half Texas late Monday, a strong capping inversion across our region will begin to erode as we cool aloft with rapid development of thunderstorms expected as early as late afternoon in our westernmost zones and farther east as we progress through the evening and overnight hours. Sfc-based CAPE values could be pushing 2000-2500 J/kg during this late Monday into Monday evening timeframe so this certainly justifies the convective outlook in SPC`s Days 4-6 with similar values expected again on Tuesday and Wednesday as we remain very warm and unstable ahead of a cold front finally expected to arrive Wednesday night into Thursday with increasing bulk shear during this timeframe ahead of the cold front. All modes of severe weather will possible from early to mid week, in addition to the threat of heavy rainfall and flooding as we will remain mired in SW flow aloft for much of the period next week. As the cold front clears the region later on Thursday, we should finally see a reprieve from the wet and unsettled weather to end the period. Temperatures will also return closer to seasonal averages as well with highs in the mid 70s to lower 80s on Thursday afternoon as a more zonal pattern sets up through the end of the workweek on Friday. /19/ && .PRELIMINARY POINT TEMPS/POPS... SHV 47 67 41 79 / 0 0 0 0 MLU 45 65 40 75 / 0 0 0 0 DEQ 40 64 34 75 / 0 0 0 0 TXK 44 64 39 76 / 0 0 0 0 ELD 42 63 37 74 / 0 0 0 0 TYR 44 68 41 80 / 0 0 0 0 GGG 44 67 39 79 / 0 0 0 0 LFK 44 70 41 82 / 0 0 0 0 && .SHV WATCHES/WARNINGS/ADVISORIES... AR...None. LA...None. OK...None. TX...None. && $$ 26/13