Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 06/06/24


Area Forecast Discussion
National Weather Service Boston/Norton MA
1013 PM EDT Wed Jun 5 2024 .SYNOPSIS... A large cluster of showers and perhaps isolated thunderstorms move across the region Thursday morning with brief heavy rain. A second round of more scattered showers & thunderstorms cross the region Thursday evening.Unsettled conditions with periods of showers and thunderstorms Friday through Monday. && .NEAR TERM /UNTIL 5 AM THURSDAY MORNING/... 1010 PM update... Main challenge in the short term is how far inland stratus and fog gets. Patchy stratus is starting to develop along the south coast and will become more widespread here as BL cools with dewpoints in the low-mid 60s. With low level SW flow expect the stratus to advect north across the region and HREF is indicating high probs of lower cigs expanding northward overnight. However, the low vsbys in fog should be mainly confined to the south coast given the SW flow. Overnight low temps should only drop into the 60s given the increasing clouds and higher dewpoints. Leading edge of showers and t-storms moving into eastern PA and southern NJ. This activity may reach portions of CT and SW MA toward daybreak. && .SHORT TERM /5 AM THURSDAY MORNING THROUGH THURSDAY NIGHT/... * Large cluster of showers & perhaps iso t-storms and brief downpours Thu AM with the highest confidence across CT/RI & SE MA * A second round of more scattered showers & t-storms Thu evening Details... Thursday and Thursday night... Vigorous shortwave energy approaches from the west toward daybreak Thu. The amount of forcing should generate a large cluster/fairly widespread area of showers and perhaps isolated t-storms given showalter indices dropping near zero. In addition...Pwats on the order of 1.50 to 2" so expect some downpours with the activity as well. This activity should move fast enough to prevent any significant issues...but typical brief nuisance poor drainage street flooding is possible. This cluster of activity should exit most of the region by early afternoon. We should see a lull in the activity for the rest of the afternoon...although it should remain cloudy in most locations with onshore flow. It is possible though a few breaks develop in the distant interior. Mainly skies will hold highs in the 70s...but might be near 80 in the lower elevations of western MA & CT. The other concern will be a second round of more scattered showers & t-storms Thu evening...but not as widespread as what we are looking at during the morning. This is association with another shortwave and some leftover diurnal heating/instability. Surface instability of 1000+ J/KG may develop in the distant interior if we can muster a few breaks in the clouds. Mid level lapse rates are poor and the activity is not arriving until the evening will limit the severe weather potential with this activity. That being said...the HREF does indicate some updraft helicity swaths and the CSU & HRRR Neural network machine learning probs do indicate a low risk for a few severe storms across the distant interior. In a nutshell...thinking the risk for severe weather is low but can not rule out a few strong to marginally severe storms in the distant interior. Overall...think this is a low risk but can not rule out a few strong to marginally severe storms across interior MA & CT Thu evening. Brief downpours are possible with this activity too. This activity may reach eastern MA & RI in a weakened form later Thu evening. Otherwise...drying trend after midnight with lows in the upper 50s to the middle 60s. && .LONG TERM /FRIDAY THROUGH WEDNESDAY/... * Unsettled Friday through Sunday with several chances for rain and isolated Thunderstorms * Pattern improvement delayed until early/mid next week as low pressure over southern Canada is displaced by building mid-level ridge Friday... Broad upper level low that has been slowly creeping towards New England from the northwest sets up shop over the Great Lakes/southern Canada by early Friday. Several shortwaves will rotate around the low, the first of which develops mid day Friday while somewhat of a seabreeze/back door coastal front drops south out of Maine. While the dynamics of the day don`t look super impressive, thinking that some scattered showers and thunderstorms will be able to develop in the convergence zone of the two "forcing features" where some modest instability, ~600J/kg SBCAPE is present. 0-6km bulk shear also looks to be supportive of thunderstorm development, topping out around 60kt Friday afternoon! At present, this convergence zone appears to set up between Worcester and Boston along I-495, but may shift over the next 24 hours. The limiting factors in storm coverage and strength are typical of southern New England with lackluster mid level lapse rates, less than 5C/km, and decreasing PWATs as surface cold front approaches from the west; PWATs drop from near 1.8" early Friday to 1". So, while the severe potential remains very low, cant rule out some solid downpours and gusty winds Friday afternoon. Overall, should see a mix of sun and showers with a moderate mugginess to the air with dewpoints in the low and mid 60s the first half of the day. Saturday and Sunday... Unsettled conditions continue Saturday and Sunday, though neither day appears to be a washout with a few more shortwaves rotating around the persistent upper level low. Saturday looks to be the drier of the two days as PWATs fall to around 0.8" behind surface cold front that passes through overnight. Guidance is split on the shower potential, with more coarse resolution global guidance, like the GFS, trending towards a drier day and hi-res guidance like the NAM initiating more widespread shower activity Saturday afternoon. Dynamics appear to be more supportive of thunderstorms, compared to Friday, as mid level lapse rates increase to ~6C/km and low level lapse rates approach 8.5C/km, but instability appears to be quite poor, around 200J/kg. PWATs surge back towards 1.25-1.4" early Sunday with a similar dynamic setup, which will yield more showers and isolated Thunderstorms compared to Saturday. Still, not expecting a washout, with a mix of sun and showers. Early next week and beyond... Very persistent mid level trough/low pressure over Canada, remains near stationary through early next week. Guidance shows stronger shortwave development in the Monday period that could bring a more substantial shot of QPF to the region, before a brief reprieve from unsettled conditions develops Tuesday/Wednesday with some indication that strong mid level ridging develops during that timeframe. While ridging looks robust, temperatures look seasonably mild rather than hot, with highs in the 80s. && .AVIATION /02Z THURSDAY THROUGH MONDAY/... Forecast Confidence Levels: Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent. 00z TAF Update... Tonight into Thursday night...High Confidence on trends but lower confidence on specific timing. Light moist southerly flow will allow for low stratus and areas of fog to overspread the region tonight from south to north. Specific timing uncertain...but do expect most locales to see IFR-LIFR conditions develop overnight. These conditions will continue through much of Thursday. Improvement will occur Thu night across the interior...but lower conditions will persist for most of Thu night across the eastern half of the region. The other concern over the next 36 hours will be for a band of widespread showers and perhaps isolated t-storms that will cross the region from southwest to northeast Thu morning. Brief downpours are expected with this activity too. A second area of scattered showers & t-storms will impact the region from the west Thu evening...but this activity will be more scattered than what we are anticipating during the morning. As for wind...they will be from the S generally 10 kts or less...but will shift to the E on Thu across northern MA. Prob30 groups have been added to the TAFs, away from the south coast/Cape, to account for two periods of potential convection; the first between ~13-17Z west to east, and the second between 21-01Z (Friday) west to east. The second round of convection looks to be shorter lived, associated with a thin line moving from the SW to NE, this currently looks to miss the Cape and Island terminals completely. KBOS TAF...High confidence in trends, but lower confidence in specific timing. KBDL TAF...High confidence in trends, but lower confidence in specific timing. Outlook /Friday through Monday/... Friday: VFR. Chance SHRA, isolated TSRA. Friday Night: VFR. Slight chance SHRA. Saturday: VFR. Breezy. Chance SHRA, isolated TSRA. Saturday Night: VFR. Slight chance SHRA, isolated TSRA. Sunday: VFR. Breezy. Chance SHRA, isolated TSRA. Sunday Night: VFR. Slight chance SHRA, isolated TSRA. Monday: VFR. Slight chance SHRA. && .MARINE... Forecaster Confidence Levels: Low - less than 30 percent. Medium - 30 to 60 percent. High - greater than 60 percent. Tonight through Thursday night...Moderate Confidence. Southerly winds of 10 to 15 knots will persist tonight into Thu before shifting to more of the SE across the northern waters. However...S-SW winds will persist across the southern waters into Thu night. This long S-SW fetch will build seas to around 5 feet across our southern outer-waters and we may see gusts on the order of 20 to perhaps up to 25 knots. Therefore...have hoisted small craft headlines for our southern waters Thu afternoon and night. The other concern for mariners will be areas of fog developing especially late tonight into Thu morning. A cluster of showers & perhaps isolated t-storms will cross the region Thu morning into the early afternoon. Outlook /Friday through Monday/... Friday: Winds less than 25 kt. Areas of seas approaching 5 ft. Slight chance of rain showers, isolated thunderstorms. Friday Night: Winds less than 25 kt. Areas of seas approaching 5 ft. Saturday: Winds less than 25 kt. Areas of seas approaching 5 ft. Slight chance of rain showers, isolated thunderstorms. Saturday Night: Winds less than 25 kt. Areas of seas approaching 5 ft. Sunday through Sunday Night: Winds less than 25 kt. Areas of seas approaching 5 ft. Slight chance of rain showers, isolated thunderstorms. Monday: Winds less than 25 kt. Seas locally approaching 5 ft. Slight chance of rain showers. && .BOX WATCHES/WARNINGS/ADVISORIES... CT...None. MA...None. RI...None. MARINE...Small Craft Advisory from 2 PM Thursday to 8 AM EDT Friday for ANZ254>256. && $$ SYNOPSIS...Frank/KS NEAR TERM...KJC/Frank/KS SHORT TERM...Frank LONG TERM...KS AVIATION...Frank/KS MARINE...Frank/KS
Area Forecast Discussion
National Weather Service Columbia SC
757 PM EDT Wed Jun 5 2024 .SYNOPSIS... A weak upper disturbance moving through the region will continue to generate scattered thunderstorms through early tonight. A cold front will move across the Southeast Thursday increasing chances for showers and thunderstorms. Drier air follows the front late this week into the weekend. Another cold front possible early next week, with rain potential increasing ahead of it late in the weekend. && .NEAR TERM /UNTIL 6 AM THURSDAY MORNING/... A couple lines of showers and thunderstorms have marched across the forecast area this afternoon and evening with convective intensity finally weakening. Ongoing convection moving through the western Midlands is associated with a short wave and will continue generating some convection due to the enhanced dynamics aloft. Most areas have already had one or two rounds of convection cross the area which has greatly reduced temperatures and stabilized the atmosphere so expect the convective intensity through the remainder of the evening and overnight to remain weak. Overnight there will be limited instability so outflow boundaries which intersect could generate some new cells. With debris cloudiness expected for most of the night overnight lows will be in the upper 60s to around 70. && .SHORT TERM /6 AM THURSDAY MORNING THROUGH THURSDAY NIGHT/... A positively tilted upper trough is forecast to be located over the Southeast Thursday morning. At the surface, a cold front that is associated with an upper low over the Great Lakes is anticipated to be near the Tennessee River Valley in the morning. Both of these features are forecast to move eastward through the day, bringing the chance for another round of scattered showers and thunderstorms to the area after a lull in the action in the morning. Latest hi-res guidance continues a downward trend in the precipitation chances through the day. However, I suspect there will be remnant boundaries from the convection that occurs today, which could be triggers for development. So, still think there`s a medium chance (30-50%) of showers and storms to develop. PWATs are expected to remain high ahead of the cold front, leading to the potential for heavy downpours at times. Forecast soundings show that the temperature will likely be an inverted V, which is indicative of a threat for strong winds. While the severe threat overall is low for any storms Thursday, some of the stronger storms could produce some stronger winds (>40 mph) and small hail. The cold front is expected to pass through the area during the overnight. && .LONG TERM /FRIDAY THROUGH WEDNESDAY/... Drier air is expected to be ushered in behind the cold front for Friday and through at least the first half of the weekend, which leads to high confidence (80%) in fair weather for Friday and Saturday. Some uncertainty begins to settle into the forecast beginning on Sunday into early next week as models indicate a front is forecast to slide south, bringing some chances for more rain. There are some significant differences in the model solutions with this feature as well as an upper level low, resulting in low confidence in the forecast at this point. && .AVIATION /00Z THURSDAY THROUGH MONDAY/... VFR conditions generally expected over the 24 hr forecast period outside of showers or thunderstorms and possible morning stratus. Showers and isolated thunderstorms continue to slowly work across the forecast area, impacting the TAF sites on their way. Showers are expected to diminish across the Augusta TAF sites over the next hour, with more approaching the Orangeburg site over the next couple hours. Any heavier shower or storm will be capable of brief visibility restrictions, with the most likely site to see this being OGB. These should continue to push eastward as the evening progresses with more stable air settling in after 03z and diminishing coverage. The shortwave driving this is expected to slowly push across the area and make for an interesting forecast tonight. Guidance is much more bullish on ceiling restrictions later tonight behind this feature, with HRRR, NBM, and RAP guidance all forecasting 1500-2000 kft stratus at the Columbia sites. Thinking this is reasonable given the subsidence behind the shortwave trough; though, it isn`t a home run forecast. CAE/CUB are most likely to see it develop but can`t rule it out anywhere else. It should remain stratus, with the usual caveat that AGS is a fog prone site, as a strong low- level jet is likely to develop again tonight. As we get into the day on Thursday, a cold front will approach and winds are expected to get fairly gusty by the afternoon hours. Expect another round of showers and storms to potentially develop ahead of this. EXTENDED AVIATION OUTLOOK...Scattered afternoon and evening showers and thunderstorms through Thursday with intermittent CIG/VSBY restrictions possible. && .CAE WATCHES/WARNINGS/ADVISORIES... SC...None. GA...None. && $$ SYNOPSIS... NEAR TERM... SHORT TERM... LONG TERM... AVIATION...
Area Forecast Discussion
National Weather Service Dodge City KS
605 PM CDT Wed Jun 5 2024 .KEY MESSAGES... - Return to thunderstorm chances early Friday morning with some severe weather potential early in the day, mainly southern areas closer to the Oklahoma line. - Multiple rounds of thunderstorm activity likely from Friday morning through Sunday, however timing and track of individual thunderstorm system is still very uncertain. - Much of next week looks dry as high pressure builds in and much more stable air mass in place && .SHORT TERM /THROUGH THURSDAY/... Issued at 338 PM CDT Wed Jun 5 2024 This Short Term period (Tonight through Thursday Night) will be one of the quietest 36-hour periods we have seen in awhile with essentially no chance for rain or thunderstorms...until very late in this period. On the synoptic scale, water vapor imagery and RAP analysis showed a broad ridge of high pressure extending across much of the western CONUS extending east across the Central and Southern Plains. A formidable shortwave trough was moving southeast across the Upper Midwest/Great Lakes region this afternoon which will bring another cold front south across western Kansas early Thursday morning. Winds will increase to 15 to 25 mph behind the front, particularly gusty once some insolation begins after sunrise tomorrow morning. The front will also drop surface dewpoints well down into the 40s keeping the entire forecast area stable to convective storms. Despite the strong northeast winds and low level cold advection, a full day`s worth of early-June direct insolation will still allow afternoon temperatures warm to the mid to upper 80s for highs. Tomorrow night, low level winds will veer around to the east- southeast and eventually southeast, becoming increasingly warm frontogenetic in the 06-12Z Friday time frame. Elevated thunderstorms, initiating within the 850-700mb warm frontogenetic zone, will be possible very early Friday morning, but there is quite a bit of uncertainty in placement of these early morning storms, so POPs will not be any higher than 30% on this forecast cycle for the early Friday morning period. && .LONG TERM /THURSDAY NIGHT THROUGH WEDNESDAY/... Issued at 338 PM CDT Wed Jun 5 2024 The period from Friday through the weekend is still looking quite active with multiple rounds of thunderstorm activity likely across the west central Great Plains. To kick off this active pattern will likely be some morning elevated convection as a warm front strengthens aloft (mainly 850-700mb layer). Rich Gulf of Mexico moisture will advance northward, above the surface, very early Friday morning yielding 2000-3500 J/kg MUCAPE. This would certainly be enough, along with 30-40 knots of vertical wind shear magnitude from 850-500mb, to support severe storms. The size of an early Friday morning MCS is uncertain and will have at least some impact on destabilization later in the day for surface-based convection. The broad west-northwest flow across the Rockies in the mid troposphere is an ideal setup for High Plains mesoscale convective system (MCS) development. Timing and placement of individual MCSs is far too uncertainty to predict over the weekend, however latest global model consensus is the best chance for the most favorable MCS activity across much of southwest/west central Kansas will be late Saturday or Saturday Night. As we head in to Sunday, signals from the latest global models (deterministic and ensemble systems) show an increasingly amplified upper level pattern with mean ridging across the Rockies and mean troughing across the eastern CONUS. This will push the effective polar front well to the south of southwest Kansas by late in the weekend in addition to the best thunderstorm chances to our south and west up against the higher terrain. Early next week looks quite stable to widespread convection across western Kansas. After that, models diverge significantly regarding the upper level pattern and resulting low level thermodynamic and kinematic fields. && .AVIATION /00Z TAFS THROUGH 00Z THURSDAY/... Issued at 603 PM CDT Wed Jun 5 2024 VFR flight category for all terminals during the time period. A cold front will move through early Thursday morning however the wind shift should occur with winds under 10 kts. Winds will briefly increase with some mixing in the late morning and early afternoon hours as wind speeds and gusts will be in the 15-25 kt range. && .DDC WATCHES/WARNINGS/ADVISORIES... None. && $$ SHORT TERM...Umscheid LONG TERM...Umscheid AVIATION...Tatro
Area Forecast Discussion
National Weather Service Grand Forks ND
1038 PM CDT Wed Jun 5 2024 .KEY MESSAGES... - Gusty winds Thursday over 30-50 mph are forecast across portions of eastern North Dakota and northwest into west- central Minnesota. - Scattered showers each of the next few days. - Drier conditions this weekend before shower chances return next week. && .UPDATE... Issued at 1030 PM CDT Wed Jun 5 2024 Advisory and warning criteria winds have since subsided as the boundary layer begins to decouple after sunset with surface inversion developing. As such, let the Wind Advisory and High Wind Warning expire. UPDATE Issued at 722 PM CDT Wed Jun 5 2024 Highest winds should begin to lessen in coverage as we approach sunset, but still could see more sporadic very windy gusts over 50 mph through 9 PM in portions of the Red River Valley and eastern ND. Thus, will likely keep Wind Warning and Advisory valid through then, even if majority of observations come in under criteria. Winds will remain elevated and gusty overnight given continued low level cold air advection over the area, but not to advisory/warning criteria. Showers/thunderstorms responsible for pea sized hail and gusts over 55 mph are exiting our area into central Minnesota as forcing for ascent and instability continues southeast. The chance for additional strong/severe storms has diminished. Still will see additional showers/sprinkles across the area through tonight, as lobe of vorticity continues to influence our area amid persistent CAA aloft near cloud bearing layer. && .DISCUSSION... Issued at 257 PM CDT Wed Jun 5 2024 ...Synopsis... Continue to note shortwave activity rotating around an upper low in Manitoba/Saskatchewan. Coupled with strong strong mid level cold advection and 850-700 mb flow of 40-50 kts a windy pattern is expected to continue through Thursday before flow weakens. After this upper low moves southeast along a tongue of potential vorticity stretching to the great lakes region a mid level trough finally clears the low level jet east of our area. In the meantime steep sfc- 700mb lapse and will maintain shower chances each day though diminishing through the weekend. ... High Wind Warning/ Wind Advisory... Strong 850mb flow can be noted in latest RAP analysis of 40-45 kts with a max of 50+ approaching from the SE Manitoba will overspread the upper Devils Lake basin this afternoon pushing winds into High Wind Warning criteria as 40+ mph sustained winds and gusts to 60 mph are possible. As the BL decouples this evening gusts should quickly diminish though may remain quite breezy through midnight. For tomorrow a similar pattern is forecast though thinking the core of the strongest winds aloft and PGF at the sfc will past us and only warrant a wind advisory for eastern North Dakota and adjacent portions of Minnesota. Punting on issuance to avoid confusion with current active headlines but foresee evening or night crew issuing more wind headlines. ...Fire Weather... Decreasing shower chances (see below) leading to more widespread low RH values with our remaining strong winds teaming up to give winds over 20 mph and RH as low as 30%. Knowing the bias in the dewpoint forecast would lean into upper 20s for humidity planning purposes. Winds seem to be well handled with this predictable pattern thus not expecting critical fire weather conditions but certainly to keep in the back of the mind and monitor. ...Shower Activity... Steep lapse rates and diurnal heating will continue to favor shower and thunderstorm formation. A weak shortwave rotating through the area should promote more widespread convective growth this afternoon through favoring NW Minnesota. Any collapsing storm should tap into the stronger winds aloft warranting the 5% risk across the area for wind though hail potential looks low due to shallow nature of storms. The lower freezing levels could help compensate for this however thus the 5% hail risk. Shallower boundary layer Thursday and Friday will cut down on severe chances through general thunderstorms and scattered showers remain a 30% chance each day. ...Weekend and Beyond... Thermal ridging moves in under upper troughing this weekend further diminishing precip chances for a few days before trough returns to the western CONUS bringing more shortwave activity to the northern plains early next week. Less than 30% chance for > 0.10" of precip any given day due to uncertainty in pattern evolution, though general pattern looks favorable for more rain chances. && .AVIATION /00Z TAFS THROUGH 00Z FRIDAY/... Issued at 1030 PM CDT Wed Jun 5 2024 Gusty northwest winds between 25-35kt will continue to impact TAF sites through 00Z Friday, including tonight. Winds will be relatively lower tonight through 15Z until another uptick in winds start thereafter. Gusts Thursday after 15Z are forecast to be generally between 30-40kt. MVFR CIGs are forecast to spread into northeast ND and northwest MN tonight. TAF sites forecast to be impacted include KDVL, KGFK,KTVF, and KBJI. These lowered CIGs are forecast to lift into VFR criteria around 15Z Thursday, although confidence is lowered in timing of this improvement, with a 30% chance it extends after 18Z Thursday. Isolated light rain showers/virga will remain possible tonight. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...None. MN...None. && $$ UPDATE...CJ DISCUSSION...TT AVIATION...CJ
Area Forecast Discussion
National Weather Service Green Bay WI
1031 PM CDT Wed Jun 5 2024 Updated aviation portion for 06Z TAF issuance .KEY MESSAGES... - Conditions hazardous to small craft will be possible at times from Thursday through Friday. - There will be a chance of showers at times from Thursday through the weekend. While low chances of thunderstorms may develop, the severe weather risk will be low. && .DISCUSSION... Issued at 218 PM CDT Wed Jun 5 2024 Short Term...Tonight and Thursday The latest RAP analysis and satellite imagery show a cold front moving across northern Lake Michigan early this afternoon. Precipitation along the front and associated with a shortwave aloft has exited northeast Wisconsin. Strong isolation behind the back edge of the cloud line continues to take place over western and central Wisconsin where 0-3km surface based capes (sb cape) are rapidly rising to around 100 j/kg. Will be monitoring western Wisconsin for storm intensification over the next 1-2 hours which resides within the left exit region of a 100 kt jet streak and just ahead of a potent shortwave trough. As storms push east, potential for strong to severe thunderstorms is the main forecast concern. Severe weather chances: Thunderstorms are expected to grow upscale from mid to late afternoon before entering north-central and central Wisconsin around the 5 pm hour. Despite modest instability (500-800 j/kg sb cape), wind fields aloft are forecast to significantly strengthen in the 700-500mb layer into the 60-70 kt range. Both the HRRR and RAP indicate that mid-level winds at 15 kft could approach around 80 kts over central WI by around 22z. This is upwards of 99th percentile in the NAEFS climatology. With low level lapse rates around 9 C/km and downdraft capes around 700 j/kg, potential is certainly there for damaging wind gusts out of the strongest thunderstorms. Think the highest potential will be across central and east-central Wisconsin from about 5 pm to 9 pm when the overlap of max instability and jet stream winds will occur. While a lesser concern, the strongest updrafts could also produce hail. Considering the low cape in the hail growth zone, it will likely take a rotating updraft for severe hail to develop. Effective shear is 25 to 30 kts so severe hail remains more marginal and the focus will be on damaging straight line winds. Late tonight through Thursday: A lull in the precipitation is expected overnight. Deeper low and mid-level moisture will return towards sunrise and will likely see light rain showers spread from northwest to southeast over the course of the morning across the region. That doesn`t bode well for thunderstorm chances and will remove the mention. Will also lower high temps due to cloud cover and light precip. Gusts to 30 mph will also be possible. Long Term...Thursday Night Through Wednesday Extended period will primarily be dominated by a near stationary cut- off low that is forecast settle over the eastern Great Lakes/SE Ontario. Cyclonic flow around the low will lead to low to moderate end PoPs (20-30%) at times this weekend. In addition, to the broad rain chances there will be a chance for a few embedded thunderstorms, mainly Saturday. Thursday night through Sunday... A few showers may linger into early Thursday night as the initial trough pushes off to the east. Expect dry conditions overnight through Friday as drier air filters into the mid-levels. Winds may become breezy Friday afternoon as the pressure gradient tightens, northwest winds may gusts 20-25 mph. Chance for precipitation returns Saturday as a second low pressure system moves across the MN Arrowhead and phases with the stalled low off to the east. There is a low end chance (15-25%) for a few embedded thunderstorms to develop late Saturday morning through the afternoon. With only marginal instability (MUCAPE 300- 500 J/kg) and weak shear expected thunderstorms to be weak and pulsy. One caveat here is if clouds clear out for Saturday morning and and low-level lapse rates steepen enough to get a few accelerating updrafts. In terms of rainfall amounts Saturday QPF looks low, with most locations expected to only see up to a tenth or two. Another chance for rain showers is forecast for Sunday as a piece of jet energy is progged to phase with the stalled low. Don`t expect more than a few rumbles of thunder with these showers as instability will be lacking. Rest of the extended...The stubborn low is forecast to finally release control of the region Monday as ensembles show a quick round of ridging returning drier conditions to the region. There are some signals that the next chance for showers and storms may come Tuesday as the ridge departs the region. && .AVIATION...for 06Z TAF Issuance Issued at 1030 PM CDT Wed Jun 5 2024 Scattered showers and thunderstorms will end overnight as a strong upper level disturbance moves away from the area. A few surface wind gusts to 35 knots possible with the thunderstorms. VFR conditions are expected outside any convective activity. Some clearing is possible late tonight. If there are some clear skies Thursday morning, skies will become cloudy again by afternoon, with scattered showers, especially across northern Wisconsin. MVFR ceilings are likely west of a IMT to AUW line, with VFR ceilings further east. && .GRB WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION.....MPC/GK AVIATION.......RDM
Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
1001 PM EDT Wed Jun 5 2024 .SYNOPSIS... Scattered showers and thunderstorms will develop again on Thursday. Dry Canadian air will mix across the area Friday and persist into the weekend. A chance of thunderstorms returns to the region Sunday and continues into the first half of next week. && .NEAR TERM /THROUGH THURSDAY/... As of 1000 PM EDT Wednesday: For this update, radar is mostly clear with a minor, non-threatening shower in the SC Upstate. No other new storms have formed as the area has become more stable and the environment doesn`t support much shower or thunderstorm activity. Minor tweaks to temps and PoPs to adjust for it. No other changes as the forecast is still on track. At any rate, convection will subside after sundown as whatever instability we end up with vanishes, and the shortwave translates east, taking synoptic support with it. The overnight hours will feature mostly dry conditions (although yet again, recent HRRR and RAP runs are hinting at a wave of isolated morning showers for the Upstate around daybreak) and the development of another deck of low stratus and patchy fog incited by a still-moist boundary layer. Guidance depicts this scattering out more quickly than it did today, as stronger WAA picks up ahead of an advancing cold front. The leading edge of this circulation should arrive by evening, and ahead of it, another round of afternoon convection is depicted by virtually all the guidance. Severe risk still looks hampered by weak shear...but 0-6km shear, particularly over the NC Piedmont out to the I-77 corridor, approach 20kts, enough that some strong to severe storms cannot be completely ruled out. And, with the front slowed in the latest 12z cycle of operational guidance, it arrives late enough for 1700-2300 J/kg sbCAPE to develop. Therefore, an isolated damaging wind risk can`t be ruled out with any segments that manage to get organized Thursday afternoon and evening. && .SHORT TERM /THURSDAY NIGHT THROUGH SUNDAY/... As of 100 PM Wednesday...An amplified system over the Great Lakes states will push a cold front through the area by Thursday evening. This will lead to drier and thus more comfortable conditions for Friday and Saturday. With surface high pressure in place, lows Friday night will drop into the 55-60 range in the Piedmont and to the upper 40s to lower 50s in the mountains. Highs both Friday and Saturday will be near climo, but with low relative humidity. && .LONG TERM /SUNDAY NIGHT THROUGH WEDNESDAY/... As of 110 PM Wednesday...The mid level system over the Great Lakes will further amplify creating a little more active northwest flow pattern on Sunday and Monday. This will lead to the return of pops for these days and nights, but there is a lot of uncertainty as to where and when any storms might occur. Drier conditions will return for the middle of next week as the system pushes through the area. && .AVIATION /02Z THURSDAY THROUGH MONDAY/... At KCLT and elsewhere: Another TAF period with restrictions and more complicated weather. Starting out with scattered showers and TS, but tapering off quickly. This will leave a period of VFR CIGS/VSBY through most of the overnight hours. Low level stratus will start to develop once again, socking in most terminals outside the mountains to IFR conditions. Time frame for IFR restrictions will be between 08-10z, with KCLT lowering around the 10z timeframe. Expect improvements around the 13z-14z time range, with MVFR returning. VFR conditions should return after 15z at most terminals. Another round of showers and thunderstorms expected Thursday afternoon for most sites. A PROB30 for TSRA for now and will adjust to TEMPOs as needed for those terminals with higher confidence in future issuances. Winds will remain S/SW at all sites with wind gusts picking up after 12z. Expect low-end gusts 15-20kts through the end of the TAF period and 23z at KCLT. Outlook: Drier air moves into the area by Friday morning with improving restrictions into the weekend. High pressure will linger through Saturday before another system approaches by the start of the new work week. && .GSP WATCHES/WARNINGS/ADVISORIES... GA...None. NC...None. SC...None. && $$ SYNOPSIS...DEO NEAR TERM...CP/MPR SHORT TERM...SCW LONG TERM...SCW AVIATION...CP
AREA FORECAST DISCUSSION
National Weather Service Jackson KY
1032 PM EDT Wed Jun 5 2024 .KEY MESSAGES... - Showers and thunderstorms will affect the area again late this evening into the overnight tonight. - Relatively cooler and drier weather will arrive behind a cold front passing through eastern Kentucky on Thursday. && .UPDATE... Issued at 1031 PM EDT WED JUN 5 2024 Showers and thunderstorms are developing and moving into eastern Kentucky from the west, much as predicted by CAMS from earlier today. The main threat from this round of precipitation will be downpours producing isolated areas of high water, especially in poor drainage areas. A few stronger storms are possible, especially with decent 0-1 km storm relative helicity providing some potential for rotating storms. Instability will be a limiting factor, however, especially in areas that were not able to sufficiently destabilize following late afternoon thunderstorms earlier. UPDATE Issued at 550 PM EDT WED JUN 5 2024 With the first round of convection exiting east into West Virginia and Virginia, lowered PoPs and Sky cover grids this evening before the next round of showers and thunderstorms arrive late this evening into the overnight hours. && .SHORT TERM...(This evening through Thursday night) Issued at 420 PM EDT WED JUN 5 2024 Late this afternoon the axis of a mid and upper level ridge extended from off the southeastern U.S. coast across the mid Atlantic states into Quebec. Further west, an upper level low was centered near the Saskatchewan and Manitoba border with an associated trough axis through the MS Valley. A lead shortwave was moving across the OH Valley and TN Valley with shower and some thunderstorms with heavy downpours working across the region preceding it. At the surface, an area of low pressure was located in the Manitoba into Ontario region with the trailing cold front south into the Great Lakes to mid MS Valley to Southern Plains. A secondary cold front extends from western Ontario to the central Plains and then into the western Conus. This evening and tonight, the lead shortwave will depart to the east by early this evening with the next shortwave/500 mb trough axis will continue east across the central and eastern Great Lakes and OH Valley into the Southeastern Conus and the Appalachians. Meanwhile the upper level low to the northwest will meander into Ontario and then to the northern Great Lakes through Thursday. Another shortwave trough will move into the OH Valley on Thursday. The first cold front will work across the Commonwealth and enter eastern KY late tonight and move southeast of the area on Thursday followed by the secondary cold front that nears eastern KY during the day on Thursday and then across the area on Thursday evening. The airmass is rather moist across the region, PW is analyzed in the 1.6 to 1.85 inch range while instability is rather weak with MLCAPE generally around 500 to 1000 J/kg at present, with low level lapse rates of about 6 to 7C/km. Mid level lapse rates are generally weak as well, 6C/km or less. The airmass will remain moist with deep moisture persisting ahead of the front, as PW remains in the 1.5 to 1.8 inch range ahead of the first cold front. MLCAPE is forecast by the RAP to be in the 500 to 1000 J/kg range ahead of the boundary before diminishing later tonight with lapse rates becoming meager. Locally heavy rain will remain the primary threat with any additional convection behind the convection that will depart into WV and VA within the next hour and another area of convection anticipated ahead of the next shortwave trough and the cold front. This second round of convection area of convection should taper off from northwest to southeast late tonight. A drier airmass will be in place behind the first front on Thursday, however, some shallow showers or sprinkles may accompany the secondary front and shortwave on Thursday afternoon and Thursday evening. Some fog will be possible as well tonight with low dewpoint depressions especially if showers end in a location and winds slacken. Fog will probably be more prevalent in the valleys on Friday night behind the secondary front as high pressure begins to nose into eastern KY. .LONG TERM...(Friday through Wednesday) Issued at 333 PM EDT WED JUN 5 2024 We begin the period quiet, as cold front will have passed through the area. In the mid-levels, we see a low set up near the Great Lakes and high set up in the Southern Plains, with solid agreement in the ensembles and deterministic guidance. This will lead to west to west northwest flow at the surface and much drier airmass. This will usher in an airmass that will lead to highs in the upper 70s to lower 80s, which is right around normal for this time of year. This drier weather will extend into Saturday with with highs sticking around 80 degrees. By later Saturday into Sunday, there is good agreement on increasing moisture, as the the mean of the EPS/GEFS/GEPS ensemble models show PWAT increasing toward the 1 inch range. This will be ahead of another southward moving frontal boundary, the a low forms on near the Lower Ohio Valley. This will spark of showers and perhaps a few thunderstorms Saturday night into Sunday, with peak chances on Sunday in the 30-50 percent range. In the wake of this weaker front, we don`t see quite as much of moisture drop off and given a mid-level trough axis hangs around during this time. This could lead to additional chances of showers and thunderstorms on Monday at around the 30-40 percent chance range. The the guidance begins to show divergence in the mid- and upper level pattern. The leads to a fair amount of uncertainty in the forecast for Tuesday into Wednesday. So we will continue to see small chances (around 20 percent or less) of showers and thunderstorms mainly Tuesday and Wednesday afternoon. It looks like much of the period we will see afternoon highs near normal in the mid to upper 70s in most cases. && .AVIATION...(For the 00Z TAFS through 00Z Thursday evening) ISSUED AT 731 PM EDT WED JUN 5 2024 The period begins under primarily VFR conditions within a lull between rounds of showers and thunderstorms. The next round will begin to approach and move through the area primarily after 03z this evening. The associated front may linger across the central and southern parts of the forecast area through Thursday morning, keeping showers and thunderstorms in the forecast, but is too low confidence to include in TAFs at this time. MVFR and possibly IFR cigs are possible in association with and after overnight showers and thunderstorms. Winds will average south to southwest at 10KT or less through this evening hours of the period, before winds become more westerly after about 15z Thu behind the front. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...CMC SHORT TERM...JP LONG TERM...DJ AVIATION...CMC
Area Forecast Discussion
National Weather Service North Platte NE
623 PM CDT Wed Jun 5 2024 .KEY MESSAGES... - Dry conditions will persist through Thursday. - Precipitation chances will increase beginning Thursday night and continue through the weekend. The threat for severe storms appears highest Friday afternoon/evening across far southwestern Nebraska. - Below normal temperatures are forecast for Saturday through Monday with highs generally in the 70s. && .SYNOPSIS... Issued at 330 PM CDT Wed Jun 5 2024 H5 analysis this morning had a closed low over east central Saskatchewan. A trough extended to the southeast into northern Minnesota, then south into northern Arkansas. High pressure was anchored over the Mojave Desert. Broad westerly flow extended from the Pacific NW into the central and northern Plains. Across the eastern CONUS, ridging extended from the Mid Atlantic States north into central Quebec. At the surface, strong low pressure was located over central Manitoba this afternoon. A cold front extended to the east then south across Lake Michigan, south into eastern Arkansas. A secondary, back door cold front had pushed into most of western and north central Nebraska by 2 PM CT this afternoon. Currently this feature was generally along Interstate 80 from Ogallala to North Platte. Winds immediately behind the front were northerly while winds south of the front were westerly or southwesterly. Temperatures as of 2 PM CT ranged from 72 degrees at Gordon, to 88 degrees at Ogallala and Imperial. && .SHORT TERM /THROUGH THURSDAY NIGHT/... Issued at 330 PM CDT Wed Jun 5 2024 The next 24 to 30 hours will be relatively tranquil across the forecast area. The back door cold front will be forced south into southern Kansas overnight as high pressure noses into the forecast area from the northwest. Northerly winds behind the front will gradually diminish overnight and with a dry airmass behind the front lows will bottom out in the upper 40s to around 50 for most of the forecast area. Some middle 50s are expected over far southwestern Nebraska, where winds will be slower to diminish. The surface high will build into western Nebraska, then central Kansas on Thursday. By afternoon, warmer air on the western periphery of the high, will begin to push into western and southwestern Nebraska. This will lead to highs in the lower 80s. Further east, highs will be in the middle to upper 70s. By late afternoon/early evening, southerly winds will begin to increase across western Nebraska on the back side of the exiting high. Overnight, a nice H85 low level jet will form from in western Kansas/eastern Colorado. This feature will nose into northwestern Nebraska after 06z Friday. At the same time, there are indications in the latest NAM12 soln, of increased mid level warm air advection and instability (negative LI`s computed above the H800 level) over the western Sandhills and northwestern portions of the forecast area. The latest NAM12, 3KM NAM and GFS solns do develop some limited QPF in these areas after 06z Friday, a result of elevated convection. With that in mind, went ahead and expanded the slight chance pops in the inherited forecast. Will cap pops around 20 percent since there is limited support for this with the 12z HRRR and ARW and NSSL WRF runs. && .LONG TERM /FRIDAY THROUGH WEDNESDAY/... Issued at 330 PM CDT Wed Jun 5 2024 Warmer air will continue to push into southwestern Nebraska Friday. On the leading edge of this warm air surge, a warm front will become established across portions of central into north central Nebraska. This boundary is most pronounced in the NAM 12 soln and shows up to a lesser degree in the GFS soln. SB CAPE`s reach around 3000J/KG across southwestern into central Nebraska Friday afternoon per the latest NAM12 and GFS solns. The presence of plenty of CAPE, a limited afternoon CAP and a frontal boundary, will probably lead to the development of thunderstorms late Friday afternoon/evening. As for the severe threat, there is plenty of deep layer shear to support supercell storms. Given the degree of very steep mid level lapse rates, large hail would be the favored severe hazard. However, INVOF the warm front, there could be a tornado threat, given the low level helicities forecasted in the NAM12 soln. ATTM, the latest SWODY3 has a marginal risk in far SW Nebraska. Feel there is a high probability for this risk to expand northeast into the forecast area with the SWODY2, to be issued tonight. On the heels of storms Friday night, another cold front will back into the region. This will lead to cooler temps Saturday and Sunday with highs in the 70s. The bulk of any storms/precipitation chances should remain out west along the front ranges of Colorado/Wyoming. There is a small possibility that some of this waning convection may reach western and southwestern portions of the forecast area, given the west northwesterly steering winds. Temperatures will then trend higher, as ridging across the western CONUS begins to break down and migrate east. By the middle and end of next week, widespread 90s look probable based on the latest NBM guidance. && .AVIATION /00Z TAFS THROUGH 00Z FRIDAY/... Issued at 622 PM CDT Wed Jun 5 2024 VFR conditions are expected to prevail across western and north central Nebraska tonight through tomorrow evening. Winds are expected to remain fairly calm through tomorrow afternoon across the region, with the exception of north central Nebraska. Tomorrow afternoon, winds will be strongest across north central Nebraska along and east of a line roughly from KVTN to KBBW, with predominantly northwest winds around 15 knots gusting to 25 knots. && .LBF WATCHES/WARNINGS/ADVISORIES... None. && $$ SYNOPSIS...Buttler SHORT TERM...Buttler LONG TERM...Buttler AVIATION...Richie
Area Forecast Discussion
National Weather Service Chicago/Romeoville, IL
854 PM CDT Wed Jun 5 2024 .KEY MESSAGES... - Period of showers tonight, followed by mainly dry and windy weather on Thursday. - Seasonable to seasonably cool conditions and breezy Friday through this weekend. && .UPDATE... Issued at 854 PM CDT Wed Jun 5 2024 A vigorous sheared shortwave continues to make steady progress across Wisconsin this evening, with two notable embedded vort lobes clearly evident on moisture-channel loops. A mid and upper-level thermal gradient is evident, with the Lincoln, IL sounding sampling 500 mb temperatures near -5 C, while at Minneapolis it`s nearly -20 C. Intense DCVA/height falls interacting with a region of steep mid-level lapse rates (thanks in part to the aforementioned cold 500 mb temperatures) is working to crank out high (ish) based showers and thunderstorms. It`s no surprise the vast majority of lightning activity has been confined north of the Wisconsin state line under the colder temperatures aloft, and suspect that will remain the case in our region tonight. Still, it`s just cold enough that a few lightning strikes can`t be ruled out as this activity sweeps across northern Illinois through the early overnight hours. With very steep 0-3 km lapse rates in place and a front that`s racing eastward at nearly 40 mph, a brief period of gusty winds may occur, either with the frontal passage itself and/or within any more rambunctious shower activity (numerous sites in southern Wisconsin and NE Iowa have reported gusts into the 35-45 mph range). Only made some minor updates to refine PoP trends through 1-2 AM. Otherwise, the forecast is in good shape. Carlaw && .DISCUSSION... Issued at 241 PM CDT Wed Jun 5 2024 Through Thursday Night: Early this afternoon, we find a cold front making its way across the CWA. The main body of precip pushing well out ahead of the boundary has made it way off to our east. However, a second, awfully narrow band of low-topped convective showers have popped up just ahead of the front and is moving across our southern and eastern CWA. A skinny CAPE profile and a large mid-level hydrolapse have kept the thunder away and we expect that to continue until this line moves away from the CWA late this afternoon. We`ve been quick to clear up behind the front with lots of sunshine now gracing areas north and west of I-55. Steep low level lapse rates are stirring up a 20-25 kt LLJ and bringing breezy conditions to the area today. Meanwhile, a second, more subtle cold front is currently throwing up some light showers in far north-central Iowa. These showers are expected to maintain themselves as they work into northern Illinois this evening. Ahead of this wave, forecast soundings, for the most part, have a very similar look. They feature steep lapse rates atop the diurnally-driven, near-surface inversion and anywhere from 300 to, at most, 500 J/kg of MUCAPE tucked beneath a mid level inversion. This mid level inversion will keep ELs capped at between 600 and 500 mb with the coldest air through unstable layer averaging at around -5C. Such a profile is certainly capable of producing convective showers, although will likely struggle to produce much in the way of lightning. Although since thunder isn`t entirely out of the question, left a slight chance for thunderstorms in the forecast. The highest shower coverage and best chance at seeing embedded thunderstorms will be north of I-80 where we find the more appreciable moisture and just about all of the ample instability. Additionally, a newer signal from the HRRR is for these showers to produce some gusty, non-damaging winds. This seems possible if the rain can get some of the stronger winds aloft to punch through the near- surface stability. We should start to see showers move into our northwest and approach the I-39 corridor sometime around mid- evening and progress across the CWA through the middle of the night. A stout low level jet will drop over the area from the northwest during the morning tomorrow. Steep lapse rates mixing through the jet, as well as a tight surface pressure gradient behind the departing system, will bring windy conditions to the CWA tomorrow. While there is still discrepancy on the magnitude of the jet, it looks likely that we should see regular gusts in the 25-35 mph range during the late morning and afternoon, however gusts could very well exceed 40 mph at times. An area of interest to potentially watch for higher gusts is north of I-80 and west of the Fox Valley during the latter part of the morning where some guidance thinks we may be able to mix down a 40+ kt LLJ before the jet diffuses some for the afternoon. Winds will step down during the evening, but may remain a bit gusty through the night. Doom Friday through Wednesday: An upper-level low over Manitoba will elongate across Ontario and Quebec while stalling into the upcoming weekend. This will bring a period of seasonable to seasonably cool conditions with daytime highs generally in the 70s. With shearing instability within faster WNW flow aloft on the southern extent of the upper-level low, overall guidance suggests that a developing wave will interact with a pocket of Pacific moisture to produce a low (10-30%) chance for light showers Saturday morning into the evening. Guidance typically struggles to handle the specific timing and strength of these waves this far out, so will maintain only slight chance PoPs for now. As the elongated wave begins to breakdown across the Upper Mississippi Valley on Sunday, a trailing moisture-starved trough axis brushing the CWA to the northeast may produce widely isolated shallow showers during the afternoon. Otherwise, ridging building in from the west should result in dry conditions and gradually warming conditions Monday and Tuesday. Kluber && .AVIATION /00Z TAFS THROUGH 06Z THURSDAY/... Issued at 620 PM CDT Wed Jun 5 2024 Aviation weather concerns are: - Period of showers late this evening, some with gusty/erratic winds. - Intermittent breezes/gusty westerly winds overnight before winds increase Thursday morning and afternoon. Brief window Thursday PM where winds could gust over 35 knots. A region of high-based showers continues to track east across Iowa and will arrive in the region later this evening. TEMPO groups for -RA/-SHRA look good and have largely maintained the inherited timing. Can`t entirely rule out a lightning strike with this activity, although the potential is too low to justify any mention in the TAFs. Any more robust showers will be capable of producing erratic and gusty winds. A reinforcing front will pass through, towards 03/04z INVOF RFD and closer to 05z at the Chicago-area terminals. While not in the outgoing 00z TAFs, there`s some potential winds could gust briefly to 25 knots with this feature`s arrival. Winds will increase through Thursday morning and afternoon, generally from a 280-300 direction. There`s a brief window during the early-mid afternoon where a few gusts near of just above 35 kts could materialize, although this potential appears too brief to warrant extra lines in the TAFs. Winds will remain gusty into the evening but will gradually ease with time. Carlaw && .LOT WATCHES/WARNINGS/ADVISORIES... IL...None. IN...None. LM...Small Craft Advisory from 10 AM to 10 PM CDT Thursday for Winthrop Harbor IL to Gary IN. Small Craft Advisory from 1 PM to 10 PM CDT Thursday for Gary to Burns Harbor IN-Burns Harbor to Michigan City IN. && $$ Visit us at weather.gov/chicago
Area Forecast Discussion
National Weather Service Melbourne FL
912 PM EDT Wed Jun 5 2024 ...New UPDATE... .UPDATE... Issued at 912 PM EDT Wed Jun 5 2024 Current-Tonight...WDLY SCT convection this evening N/W of I-4. Activity on a diminishing trend now, but there could be some ISOLD showers/storms along (and west of) the Kissimmee River into mid-late evening as the HRRR suggests but low confidence here. Any remaining storm threats will be occasional lightning strikes, brief gusty winds and locally heavy downpours. Conditions otherwise dry overnight. Onshore flow will become light/variable later this evening and overnight. Conditions remain warm and humid with eventual mins in the U60s to L-M70s areawide. && .AVIATION... (00Z TAFs) Issued at 733 PM EDT Wed Jun 5 2024 Sea breeze collision across Lake County this evening. We`ll see if any convection can muster across the interior/I-4 corridor, aside from some ongoing activity north of KLEE early on. Will add TEMPO groups if necessary on top of some "Vicinity" wording already in place. Onshore winds will gradually diminish and become light and variable later this evening into the overnight. Predominant offshore winds early Thu with a slow push inland of the sea breeze closer towards the coast. Higher confidence in lightning storms Thu afternoon with increased moisture and approaching shortwave, though much of this activity will occur beyond 06/18Z. Westerly steering flow will allow for higher coverage across the eastern peninsula. && .MARINE... Issued at 328 PM EDT Wed Jun 5 2024 High pressure will move farther seaward late week, ahead of a series of weak cool fronts. Minimal PoPs today and tonight over the Atlantic waters will increase Thursday into Thursday evening, as an upper level trough crosses the area. A few storms Thursday could be strong to marginally severe. While daily shower and lightning storm chances will continue through the weekend, PoPs decrease to around 20-30% or less for much of the area (~40% for the Treasure Coast waters Friday). By next weekend, a pattern change looks to bring much higher chances for showers and storms. Outside of convection, onshore flow breaks down into tonight as the ridge axis shifts south of the local waters. Prevailing offshore winds in the morning hours will back southerly to southeasterly each afternoon as the sea breeze develops. Winds will remain under 15kts through Saturday, but are forecast to increase to around 15kts Sunday and Monday, especially over the waters south of Cape Canaveral. Seas 1-3ft. && .FIRE WEATHER... Issued at 328 PM EDT Wed Jun 5 2024 Sensitive to near critical fire weather conditions will persist into this weekend, despite high pressure moving farther seaward into the western Atlantic. Rain and thunderstorm chances remain modest today, but will increase Thursday, as onshore flow breaks down and the sea breeze collision occurs over the eastern half of the peninsula Thursday afternoon. However, while the chance for precipitation will increase, widespread wetting rainfall does not appear likely. In addition to an increase in lightning strikes, this will keep fire weather conditions very sensitive. Into the weekend, rain chances will once again become limited. But, a pattern change, with much higher coverage of showers and storms, looks increasingly likely next week. Some storms Thursday could be strong, with gusty winds and hail. Above normal temperatures will keep min RH values between 40-45% for much of the area through Friday. Then, drier air this weekend is forecast to lead to near-critical to critical RH, with min RH falling to as low as 30-35% over the interior. High temperatures will reach the upper 90s into the weekend, with some daily record temperatures possible. Heat indices will be in the 100-107 degree range. Very good to excellent dispersion is forecast Thursday and Friday, with control issues likely. && .PRELIMINARY POINT TEMPS/POPS... DAB 73 94 73 95 / 10 40 20 30 MCO 75 97 74 96 / 20 40 20 30 MLB 74 93 73 94 / 10 50 30 30 VRB 73 94 72 95 / 10 60 40 30 LEE 75 96 75 95 / 20 30 10 30 SFB 74 98 74 97 / 20 40 20 30 ORL 76 97 76 96 / 20 40 20 30 FPR 73 94 72 95 / 10 60 40 40 && .MLB WATCHES/WARNINGS/ADVISORIES... FL...None. AM...None. && $$ UPDATE...Sedlock AVIATION...Sedlock
Area Forecast Discussion
National Weather Service Marquette MI
1044 PM EDT Wed Jun 5 2024 .KEY MESSAGES... - Some high-base showers and thunderstorms look to develop over the western half of the U.P. this evening. A strong thunderstorm or two with gusty winds and hail is possible. - Showery weather and much cooler conditions expected Thursday through the weekend under the influence of low pressure. && .UPDATE... Issued at 1042 PM EDT Wed Jun 5 2024 There was quite a bit of afternoon/evening thunderstorm activity with reports of hail up to dime/penny size and even some tree damage in the Ironwood area. Thunderstorm intensity gradually waned over the past 2-3 hours to the point where small hail and gusty winds are now unlikely. The only remaining cluster of storms is north of Manistique and the most likely hazards are frequent lightning and briefly heavy downpours. Upstream radar/satellite don`t show much going on so expect the drying trend to continue overnight into Thursday morning as a progressively drier air mass builds over the area so have substantially reduced PoPs through the nighttime hours. There is commingled uncertainty with tonights low temperatures, cloud cover, and winds. Generally favor mostly cloudy skies and light winds keeping the boundary layer warmer around 50F, but there are breaks in the cloud cover that may allow for locally cooler spots dipping into the 40s. && .SHORT TERM /THROUGH THURSDAY NIGHT/... Issued at 431 PM EDT Wed Jun 5 2024 GOES-16 Visible imagery shows clearing skies along the MI/WI state line behind an advancing cold front, with the band of rain showers from that front now mainly confined to the eastern half of the UP. Through 1830Z, the only electrically active storm has been a sub- severe cell that started in southern Menominee County and has transited the Bay of Green Bay and is imminently arriving at the Garden Peninsula. Under cloudy skies for much of the day, highs are around 10 degrees cooler than yesterday, mainly in the low 70s. Attention turns upstream this afternoon to the clearing in the west, which already is showing signs of some cu development supported by diurnal heating and a secondary shortwave evident on RAP Analysis 500mb heights. The 12Z HREF showed much less available instability relative to yesterday`s storms with only around 500-1000 J/kg of SBCAPE available. Shear is right around what it was yesterday with around 20 kt of effective bulk shear and 50-100 0-3km SRH. It is worth noting that while instability is surface-based, the depth of the mixed layer at the surface is around 6,000 ft, so cloud bases are going to be relatively high. Reflectivity paintball plots in the HREF show that CI will begin in northern Wisconsin and push east into the UP around 20Z, somewhat losing energy as it progresses and maintaining cellular form. Thinking hazards are once again isolated damaging wind gusts and pea to quarter sized hail from "core dumps". Less total precipitation is expected with this round of showers, with HREF mean 6-hourly precipitation only around 0.2-0.4 inches. In the wake of showers, lows look to fall to the 50s tonight, with winds staying out of the west. && .LONG TERM /FRIDAY THROUGH WEDNESDAY/... Issued at 431 PM EDT Wed Jun 5 2024 Flow over and around N America through early next week will feature pronounced high latitude blockiness. Through the remainder of this week and into the weekend, building mid-level ridging/positive height anomalies, first from ne through n central Canada and across the Arctic Ocean, and then over western N America will force mid-upper level troughing to develop from s central Canada across the Great Lakes/eastern U.S. This troughing will also force the mid-level low now over northern Saskatchewan/Manitoba to descend across the Great Lakes region beginning Thu. For Upper MI, this pattern evolution will lead to periods of showery weather and a period of blo normal temps (seasonably cool) thru early next week. However, the large scale pattern does suggest the potential of unseasonably cool days in the mix, particularly on Thu. Models have lacked run-to- run consistency and have been and continue to be quite varied on the details of the flow affecting Upper MI. So, the pcpn fcst has much more uncertainty than normal. Overall, expect many areas to be dry much of the time as showers are likely to be scattered in coverage on most days. Thu is likely to be the day with the most numerous shower coverage. With the mid-level trough weakening and shifting e early next week, dry and warmer weather is more likely to prevail for the first half of next week, although a few of the 00z models hint at another wave moving through the area in the Tuesday- Wednesday time frame that may bring the potential for some light shower activity. Beginning Thursday, the mid-level low now over central Canada will dive se across the Upper Great Lakes by Thu. A shortwave attached to the mid-level low circulation will track from northern MN se across Upper Mi in the late morning/afternoon. Forcing associated with this feature combined with the start of daytime heating will support a rapid development/expansion of showers during the morning. The showers should diminish in coverage over the w in the aftn in the wake of the wave. Considerable cloud cover will limit daytime heating/instability, so thunder potential is overall minimal. Fcst will only include a mention of thunder over the e and se fcst area due to a little more instability potential there before clouding over and development of widespread showers. Under considerable cloudiness, passing showers, rather stiff wnw winds and a 850mb thermal trough driving se into the area, it will be unseasonably cool for much of the area. Highs in the 50s F will likely be the rule across the w through n central ranging up to the lower/mid 60s F s central/se. Lakeside locations exposed to wnw winds across Lake Superior may not see max temps above 50F. W side of the Keweenaw likely to be coolest. Showers will diminish Thu night in the wake of shortwave, but won`t end, particularly over the e where showers may keep going in response to some isentropic ascent as warmer air to the n and ne weakly advects toward the thermal troffing over the area. On Fri, center of mid-level low drifts e toward southern Ontario. Weak shortwave ridging develops into western Upper MI between that low and another mid-level low over s central Canada. This is suggestive of fewer showers over western Upper MI on Fri compared to Thu, with more areas likely to be dry through the day. To the e, closer to the mid-level low, shower coverage will be greater. High temps on Fri will be coolest over the e where more clouds/shra are expected. Mid 50s to around 60F expected there. Low/mid 60s expected to the w, except closer to Lake Superior where temps will be in the 50s. Sat, models seem to be coming into a little bit better agreement on a shortwave trough moving through the area. MLCAPE values of 100-300 j/kg could maybe even support a rumble of thunder along the WI border and south central late morning into the afternoon. Expect scattered shower coverage with highs generally in the 60s, except for some 50s readings near Lake Superior in a continued nw flow. Sun, although model consistency isn`t great on exact details most of the models hint at another shortwave/mid-level trough axis moving through the area in the Sat night into Sunday time frame. Would expect at least isolated showers from feature perhaps aided by some weak isentropic ascent from the north as winds shifting from nw to n bring a pocket of warmer 850 mb air into the area. North flow off Lake Superior will result in 50s readings near the lake while 60s readings will be more common inland. With medium range models trending toward more ridging building over the area on Monday behind the exiting mid-level trough, would expect drier and warmer conditions on Monday with highs mostly in the 60s to lower 70s, with warmest readings inland toward the WI border. Models and ensembles then hint at a shortwave trough moving through in the late Tue into Wed time frame which could result in at least isolated showers again. Temps are expected to rebound to around normal values for this time of year with highs mainly in the 70s Tue into Wed. && .AVIATION /00Z TAFS THROUGH 00Z FRIDAY/... Issued at 134 PM EDT Wed Jun 5 2024 VFR prevails at all TAF sites to begin this afternoon. -SHRA has moved out of IWD and CMX with SAW forecast to also clear out of precip in the next hour or two. This evening, a second wave of showers is expected to move in from the west, with some stronger TSRA possible at IWD. VFR is expected to prevail through these SHRA/TSRA. In the morning hours, low (20-40%) SHRA chances return to the forecast along with likely (50+%) reductions in ceiling height to MVFR, though models have trended later with the onset of MVFR conditions over the last few model cycles. Expect winds to remain primarily out of the west, occasionally gusty. && .MARINE... Issued at 431 PM EDT Wed Jun 5 2024 A low pressure trough moving in from the west could lead to a few stronger thunderstorms developing over MN and moving out across western Lake Superior late this afternoon/evening, posing a risk of locally strong wind gusts. Late tonight continuing into Fri, steady w to wnw winds generally at around 20kt with occasional gusts to 30kt will set in from w to e with the highest gusts over the east half. A slight diminishing of winds will occur over the weekend with sustained speeds falling back to around 15kt as winds shift from northwest to north-northwest on Sunday. North winds should diminish blo 15 kts on Monday as a high pressure ridge builds in from the northwest. && .MQT WATCHES/WARNINGS/ADVISORIES... Upper Michigan... None. Lake Superior... None. Lake Michigan... None. && $$ UPDATE...EK SHORT TERM...GS LONG TERM...Voss AVIATION...GS MARINE...Voss
Area Forecast Discussion
National Weather Service Nashville TN
859 PM CDT Wed Jun 5 2024 ...New UPDATE... .UPDATE... Issued at 856 PM CDT Wed Jun 5 2024 Showers and thunderstorms in northern AL have weakened as they continue northward into the mid state, but still pose a severe threat for northern AL. Some gusty winds remain possible with the showers and storms moving into the southwest zones, but CAMs continue to weaken the activity as the evening goes on. But, will continue to monitor for any strengthening, or, any additional development with the approaching cold front from the northwest. Made some minor edits to the near term forecast to reflect latest guidance. No other changes to the forecast. && .SHORT TERM... (Rest of today through Thursday) Issued at 1007 AM CDT Wed Jun 5 2024 The morning sounding from OHX is rather underwhelming. There is some instability, but not a great deal. The surface-based CAPE is just 333 J/kg, with a Lifted Index of -2, and the 700-500 mb lapse rate is a measly 5.2 C/km. The column is nearly saturated all the way up, and without any sort of dry layer aloft, we just aren`t getting steep enough lapse rates to produce any meaningful instability. The 0-3 km helicity is 136, but this is due mostly to speed shear. There is very little directional shear present. The Precipitable Water is a robust 1.77", which gives us a PWAT+ value of 148 (observed PWAT is 148% of the daily mean value), and puts us well above the 90th percentile for June 5. Anyway, once this initial line of showers passes through Middle Tennessee, the HRRR shows very little activity until later tonight with the passage of the actual surface boundary. After that, nothing. && .LONG TERM... (Thursday Night through next Wednesday) Issued at 1007 AM CDT Wed Jun 5 2024 High pressure will keep us mostly sunny and less humid through Friday. What looked to be a sunny weekend not so long ago is now looking like a rainy one, especially Sunday. On Saturday, a weak shortwave will bring some additional cloudiness with low rain chances to Middle Tennessee. And on Sunday, an east-west oriented surface boundary will sag southward through the mid state and bring even better rain chances. Fortunately, QPF values on Saturday and Sunday are very low. In other words, these will be nuisance showers rather than washouts. As a result of tonight`s frontal passage, temperatures will cool off several degrees beginning Thursday night and Friday, with relatively cool weather lasting at least until the middle of next week. && .AVIATION... (00Z TAFS) Issued at 631 PM CDT Wed Jun 5 2024 A line of showers and isolated thunderstorms will push in from the west after 00Z. They will be spotty in nature as the high resolution models have been overdoing the precipitation. Will utilize VCSH/VCTS for stations west of the Plateau (KCKV/KBNA/KMQY). The line clears off the Plateau by 17-20Z. There could still be a period of MVFR/IFR CIGs around sunrise before returning to VFR. Also MVFR/IFR will be possible in the heavier thunderstorms. Winds will be westerly and then turning northwesterly and gusting to 20kts after 22Z when the weak front pushes through. && .PRELIMINARY POINT TEMPS/POPS... Nashville 70 88 63 84 / 40 10 0 0 Clarksville 67 86 59 83 / 40 0 0 0 Crossville 64 80 55 75 / 50 50 0 0 Columbia 68 88 60 82 / 40 10 0 0 Cookeville 66 82 56 77 / 50 40 0 0 Jamestown 65 81 55 75 / 50 50 0 0 Lawrenceburg 67 86 61 80 / 50 10 0 0 Murfreesboro 68 88 60 82 / 40 20 0 0 Waverly 67 87 61 82 / 50 0 0 0 && .OHX WATCHES/WARNINGS/ADVISORIES... None. && $$ UPDATE.......Barnwell SHORT TERM...Rose LONG TERM....Rose AVIATION.....12
Area Forecast Discussion
National Weather Service Tampa Bay Ruskin FL
807 PM EDT Wed Jun 5 2024 ...New UPDATE, AVIATION... .UPDATE... Issued at 807 PM EDT Wed Jun 5 2024 Early evening water vapor satellite imagery is showing a fairly dry airmass aloft of the Florida Peninsula early this evening, with only a few stray showers and storms managing to break through across the area this afternoon. 00z KTBW radar imagery is also showing the east and west coast sea breezes continuing to push inland and about to collide over interior portions of the forecast area, so a few more storms developing this evening can`t be ruled out yet...but most locations will need to continue waiting for a chance of rain. Overall, the forecast looks on track for a mostly dry day again on Thursday near the coast, with some afternoon and evening showers mainly over the interior. A few minor rain chances were made for the next couple of hours to keep up with radar and satellite trends. No other changes are planned for the evening update. && .DISCUSSION... Issued at 224 PM EDT Wed Jun 5 2024 Weak upper ridging extends northward along the eastern seaboard, while surface high pressure north of the Bahamas ridges west over Florida and into the Gulf of Mexico. This is keeping a predominant easterly flow over the region today. Latest HRRR guidance has showers and storms developing over the interior later this afternoon/evening with the highest coverage over Polk and Highlands Counties with the west and east coast sea breeze collisions. By Thursday morning, the upper ridging and surface high move southeastward while a weak frontal boundary and upper troughing moves through the southeast U.S. This will bring a shift in the winds to the south during the morning and then westerly by the afternoon hours. This boundary will stall out north of the area through the end of the week, while weak high pressure ridges over south Florida. PWAT values will fluctuate between 1.5 - 1.7 inches through the end of the week, which will support scattered showers and isolated storms. The boundary pushes south and east of the area by Saturday allowing for weak high pressure to build in over the eastern gulf. This will keep predominant westerly winds over the area and will also usher in some slightly drier air with PWAT values dipping to around 1.1 - 1.4 inches over the weekend. This will limit shower and storm activity on Saturday and Sunday. The ridge will lift slightly northward by the start of next week, putting Florida under a south-southwesterly wind flow. This will equate to higher PWAT values in the 1.6 - 2.0 inches range. This increasing moisture will bring more widespread showers and storms for the first half of next week. Daytime highs will top out in the low to mid 90`s each day with overnight lows in the 70`s. && .AVIATION... (00Z TAFS) Issued at 807 PM EDT Wed Jun 5 2024 A few showers or storms are lingering along sea breeze boundaries and could still impact area terminals tonight, mainly around KLAL and KRSW, KFMY, and KPGD. Elsewhere, rain chances are too low to mention in the TAFs at this time, but a stray shower overnight is not out of the question. Mainly dry and VFR conditions will continue on Thursday, with a few showers or storms possible over the interior and around southwest Florida. && .MARINE... Issued at 224 PM EDT Wed Jun 5 2024 High pressure north of the Bahamas is expected to start shifting southeast later today into tonight. Predominant easterly winds become onshore with the afternoon sea breeze. Showers and storms should develop over the land this afternoon/evening, drifting into the Gulf during the late evening and early overnight hours. A weak frontal boundary approaches the Gulf waters on Thursday and Friday, which will shift winds to the west through the end of the week. As a result, showers could develop along the coast early and push inland during the afternoon. Winds will remain less than 15 knots and seas 2 feet or less through the period. && .FIRE WEATHER... Issued at 224 PM EDT Wed Jun 5 2024 High pressure begins to gradually move southeast today as a weak boundary approaches the area on Thursday and Friday. Scattered showers and isolated storms possible through the end of the week. The boundary moves southeast of the area by Saturday allowing for high pressure to build into the area, which will usher in some slightly drier air over the weekend. Some critical RH values below 35 percent will be possible on Saturday and Sunday afternoon, but winds are expected to be light so no Red Flag Warning should be needed. Moisture rebounds by next Monday as a more southerly wind flow sets up over the region. Higher rain chances also expected for the first half of next week. && .PRELIMINARY POINT TEMPS/POPS... TPA 79 93 79 92 / 10 10 30 40 FMY 77 95 77 94 / 20 10 30 40 GIF 74 98 74 96 / 20 30 20 40 SRQ 78 93 79 92 / 10 0 30 30 BKV 71 95 72 93 / 10 0 30 40 SPG 82 92 82 91 / 10 0 30 40 && Sea Breeze Thunderstorm Regime For Thursday: 4 Sea Breeze Thunderstorm Regime For Friday: 4 For additional information on sea breeze regimes, go to: https://www.weather.gov/tbw/ThunderstormClimatology && .TBW WATCHES/WARNINGS/ADVISORIES... FL...None. Gulf waters...None. && $$ UPDATE/AVIATION...Fleming PREVIOUS DISCUSSION/MARINE/FIRE WEATHER...Wynn