Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 06/25/21

Area Forecast Discussion
National Weather Service Charleston SC
928 PM EDT Thu Jun 24 2021 .SYNOPSIS... High pressure will remain over the area through tonight. A coastal trough will then move over the area Friday through Saturday. Atlantic high pressure will rebuild Sunday through the middle of next week. && .NEAR TERM /UNTIL 6 AM FRIDAY MORNING/... The Coastal Flood Advisory from Beaufort County south to McIntosh County has been cancelled. Tides at Fort Pulaski peaked just below the 9.5 ft MLLW advisory threshold. The Coastal Flood Advisory for Charleston and Coastal Colleton continues until 11 PM as levels are above minor flood criteria. Otherwise, the forecast is in good shape. Lows were nudged down 1-2 degrees for most locations as the cool trend in both the RAP and H3R continues. High pressure will hold firm over the area tonight as a coastal trough begins to approach the coast. Shower activity associated with this feature will move slowly west with time, but will encounter a very dry airmass that is currently in place across coastal South Carolina and Georgia. The onset of mentionable pops were delayed by several hours per latest high-res guidance and values were lowered slightly prior to daybreak. Rain chances will ramp up after daybreak, especially across Southeast South Carolina along/east of the I-95 corridor. && .SHORT TERM /6 AM FRIDAY MORNING THROUGH SUNDAY/... The mid-levels will consist of a ridge building over the Southeast with time. At the surface, a coastal trough is expected to develop on Friday, then move inland on Saturday. Meanwhile, Atlantic high pressure will remain far offshore. The trough will bring increased moisture to our region with PWATs exceeding 1.5". Models are in fairly good agreement indicating diurnal convection throughout the short term. Though, they do hint at a bit more coverage and precipitation on Friday and Saturday, which is reflected in our POP forecast. Instability isn`t that impressive for this time of year due to all of the moisture in place, so the overall severe risk is low. However, steering flow could be relatively light. Locally heavy rainfall could occur in areas with training or back-building storms. Otherwise, the moisture and clouds will keep high temperatures below normal. && .LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/... A rather persistent weather pattern will be in place with mid-level ridging over the Southeast and surface high pressure in the Atlantic. As a result, the NBM generally has diurnal showers/thunderstorms with temperatures at or slightly below normal. && .AVIATION /02Z FRIDAY THROUGH TUESDAY/... VFR. Risk for showers could increase closer to daybreak at KCHS and KJZI, but impact/timing probabilities suggest keeping a mention of VCSH for now, mainly 15-20z. Extended Aviation Outlook: Brief flight restrictions are possible due to showers/thunderstorms, mainly each afternoon and evening. && .MARINE... Seas at 41008 continue to rise slowly and should remain around 6 ft for the next few hours. The Small Craft Advisory has been expanded to include the Georgia nearshore waters. Tonight: A coastal trough will work its way into the coastal waters in the overnight period, causing the pressure gradient to weaken and therefore the winds will subside. Winds should shift to more E 10 to 15 knots with seas diminishing to 2 to 4 feet. Extended Marine: A coastal trough will develop on Friday, then move inland on Saturday. High pressure will remain in the Atlantic next week. The overall synoptic pattern will lead to mainly onshore winds. Seas are expected to remain 5 ft or lower. No Small Craft Advisories are expected. Rip Currents: The combination of moderate northeast winds and mixed swell near 8 and 14 seconds will lead to a Moderate Risk of rip currents at all of our beaches today. Winds should ease a bit on Friday, resulting in the low risk. && .TIDES/COASTAL FLOODING... A risk for minor coastal flooding will persist into Friday evening`s high tide, especially for coastal portions of Charleston and Colleton Counties. && .CHS WATCHES/WARNINGS/ADVISORIES... GA...None. SC...Coastal Flood Advisory until 11 PM EDT this evening for SCZ049- 050. MARINE...Small Craft Advisory until 11 PM EDT this evening for AMZ354- 374. && $$
Area Forecast Discussion
National Weather Service Goodland KS
515 PM MDT Thu Jun 24 2021 .UPDATE... Issued at 403 PM MDT Thu Jun 24 2021 Thunderstorms are beginning to move towards Yuma, Kit Carson, and Cheyenne counties. A Severe Thunderstorm Watch is in effect until 10 PM MT for all of the Tri-State area except for Red Willow, Norton, and Graham counties. Hazards include up to 2" hail and damaging wind gusts up to 80 mph. && .SHORT TERM...(This evening through Friday) Issued at 319 PM MDT Thu Jun 24 2021 This afternoon-Tonight...Despite being beneath an upper level ridge, shortwaves, a lee trough, and a surface low over central Kansas will make for an interesting evening in the Plains. A multitude of shortwaves are making their way across the Four Corners this afternoon along the southern edge of an upper level trough over the Intermountain West while pushing the lee trough east away from the Front Range. As of 2 PM MT, storms are already beginning to develop near the Palmer Divide along a southeast- oriented axis in the trough. Initially these storms are expected to be scattered with a few supercells possible. Over the course of the evening, the storms will continue east across W Kansas and SW Nebraska evolving into a more linear (MCS) storm mode. The HRRR and RAP models are continuing to show a favorable environment for storms with MLCAPE 1000-2500 j/kg for much of the area and increasing more to the east and effective shear in the 40-50 kts range. With the high based cloud cover and light showers over portions of the area, there is some weak CIN (< -200 j/kg) which may help limit the strength of the convection. The recent runs of the HRRR and RAP are continuing to become more favorable for a few tornadoes this evening. Confidence is low to moderate considering the time of the day, not as favorable SRH values, and backing winds near the surface. The main hazards are large hail up to 2" and up to 80 mph damaging winds gusts. If/when these storms evolve into an MCS, the hail threat is expected to decrease while the wind threat increases. On the backside of the MCS, more convection may develop with a much lower severe threat. Overnight lows will be in the mid 50s to mid 60s overnight. Friday-Friday night...The upper level trough is expected to move into the Four Corners region during the afternoon. Another round of scattered thunderstorms are possible tomorrow from 4 to 11 PM MT. With lingering cloud cover and limited time for the atmosphere to recover from tonight`s event, the environment doesn`t appear to be as favorable. MLCAPE values around 1500 j/kg or less with mid-level lapse rates in the 6-8 C/km range and 25-40 kts of shear. Main hazards are expected to be damaging winds and hail. Afternoon highs are expected to be in the upper 70s to mid 80s with overnight lows in the mid 50s to lower 60s. .LONG TERM...(Saturday through Thursday) Issued at 157 PM MDT Thu Jun 24 2021 At the start of the period, an upper trough extends from the northern Plains to the Desert Southwest. Meanwhile, an area of high pressure is located over southwestern Canada and the Pacific Northwest, with ridging along the west coast. For this weekend, the upper trough remains in place over the central CONUS due to nearly stationary high pressure along the east coast serving as a block. This keeps west to northwest flow above the region on the western side of the trough. Disturbances pass through the flow on both Saturday and Sunday, resulting in chances for showers and thunderstorms both days. Severe weather is not currently anticipated. The weekend pattern prevails into early next week, with the positively tilted upper trough across the central part of the country and high pressure to the west (Pacific Northwest) and east (east coast). There are some differences among guidance for what will happen through the week with the pattern. Some solutions have the trough slowly shifting eastward and perhaps closing off to a low while others keep it firmly over the Plains. Either way, chances for showers and thunderstorms return each day, particularly in the afternoon and evening hours. Will work to refine details later in the period. A warming trend will be possible during the long term as the upper trough potentially shifts east and allows ridging to nudge into the region. High temperatures are forecast in the 70s and low 80s Saturday through Monday. A gradual rise follows, from the mid 70s through mid 80s on Tuesday to the 80s region-wide on Thursday. Low temperatures are mainly in the 50s through the period, plus or minus a few degrees. && .AVIATION...(For the 00Z TAFS through 00Z Friday evening) Issued at 510 PM MDT Thu Jun 24 2021 For KGLD and KMCK, VFR conditions are currently expected through the period. The general scenario calls for showers and thunderstorms to potentially impact KGLD in the 03z-07z timeframe with strong wind gusts the primary hazard. From 08z-15z there is a possibility of stratus and sub VFR cigs and maybe some fog/mist. After 16z VFR conditions return. There is a small chance for thunderstorms after about 23z. Winds at taf issuance gusting up to 20kts or so from the northeast, otherwise generally variable in direction at speeds under 8kts. For KMCK any chance for convection would be in the 06z-11z timeframe at this time. Sub VFR cigs in stratus are possible from 12z-17z. Winds through the period generally from the northeast, strongest at taf issuance where gusts up to 20kts or so expected. Adjustments to the forecast for both sites will likely be needed as the convective threat develops this evening. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ UPDATE...KMK SHORT TERM...KMK LONG TERM...JBH AVIATION...99
Area Forecast Discussion
National Weather Service Lincoln IL
1000 PM CDT Thu Jun 24 2021 .SYNOPSIS... Issued at 319 PM CDT Thu Jun 24 2021 Several rounds of storms are expected over the next 36 hours across central Illinois, resulting in the potential of 3 to 5 inches of rainfall and possible flash flooding. Overnight lows will be in the lower 70s with highs on Friday in the lower to middle 80s. && .UPDATE... Issued at 906 PM CDT Thu Jun 24 2021 Clusters of heavy thunderstorms have been moving slowly eastward along the I-72 corridor between Jacksonville and Decatur this evening, mostly delivering torrential rainfall. Hourly precip rates have ranged between 2-3", but the mid-level flow and an upstream shortwave trough have been enough to prevent training storms. Latest surface analysis (02z) depicts a zone of weak convergence extending from roughly Macomb to Taylorville. While this feature has been the focus for convection thus far this evening, the expectation is for the MCS across northern Missouri to continue making an east/southeast push overnight. There remains some uncertainty on the strength of the MCS as it pushes east of the Mississippi River Valley. While the 0-3 km shear vectors are progged to hover near or above the 30 kt threshold needed to keep the system cold pool balanced, the orientation of the shear vectors look roughly parallel to the line of convection. This would likely diminish the severe threat across our outlook area overnight into Friday morning. A decaying MCS/MCV would still pose a heavy rainfall threat across a portion of our outlook area, however. Latest CAM guidance suggests the heavier axis of precip stays along and south of I-72 into Friday morning, and this makes sense given the current MUCAPE gradient draped just north of a warm front positioned along the I-70 corridor in Missouri. Convection will likely follow this instability gradient southeastward. The one wild card overnight is a secondary heavy rainfall axis that may develop roughly north of a Macomb to Kankakee line. This would be tied to the portion of the MCS that maintains a line- normal component of the 30+ kt 0-3 km shear vectors. The latest HRRR runs have begun to latch onto such a solution with a narrow swath of 2-3" QPF overnight. Bottom line, it`s looking like much of central Illinois will get split by the MCS currently across northern Missouri. Additional heavy rainfall chances still exist through the weekend... && .SHORT TERM...(This evening through Friday night) ISSUED AT 319 PM CDT Thu Jun 24 2021 Storms across the eastern part of the CWA will continue to move east and wain through the rest of the afternoon and into the evening. Then a lull in the precip is expected across the area. However, another round of precip/storms is expected to develop tonight out west and then move toward central IL during the late evening to overnight hours. HiRes models have different solutions but all do bring a decent amount of rainfall to the area during the overnight hours. Additional rainfall is possible Friday and again Friday night as 2-3 more rounds of storms could develop over the area or move into the area. Due to the area getting multiple rounds of storms over the next 36 hours, A flash flood watch has been issued for most of the area, mainly north of the I-70 corridor, for tonight through Friday night. Highs tomorrow should be in the middle 80s with overnight lows in the lower 70s. .LONG TERM...(Saturday through Thursday) ISSUED AT 319 PM CDT Thu Jun 24 2021 The chance of showers and storms will continue through the extended period as southwest flow returns to the area for at least the first half of next week. Both long term models are currently indicating this so due to the agreement, confidence is higher than normal for an extended forecast. Temps at the beginning will be quite warm, starting off in the mid to upper 80s across the area. Then temps will slightly cool for the rest of the extended period, with mid 80s common across the area. Overnight lows should start in the lower 70s but then drop into the upper 60s for the last half of the period. && .AVIATION...(For the 00Z TAFS through 00Z Friday evening) Issued at 625 PM CDT Thu Jun 24 2021 PIA/SPI/BMI: While initial thunderstorm coverage will be scattered, the idea is for it to become more widespread by 03z. Latest satellite and radar trends seem to coincide poorly with our short- term models, but TSRA will become likely between 03z-09z. Cigs will largely stay in the MVFR range during this TAF period, even as thunderstorm activity wanes by 12-15z Friday. Winds will predominately blow from southwest to northeast with sustained speeds between 10-15 kts and occasional gusts between 25-30 kts within heavier showers and thunderstorms. DEC/CMI: Higher thunderstorm coverage will move in by 06z, with TSRA becoming likely between 06z-12z. Cigs will be VFR prior to that time frame, with MVFR cigs becoming the predominate ceiling for the remainder of the TAF period, even as thunderstorm activity wanes by 15z Friday. Winds will predominately blow from southwest to northeast with sustained speeds between 10-15 kts and occasional gusts between 25-30 kts within heavier showers and thunderstorms. && .ILX WATCHES/WARNINGS/ADVISORIES... Flash Flood Watch through Saturday morning for ILZ027>031- 036>038-040>057-061. && $$ UPDATE...MJA SYNOPSIS...Auten SHORT TERM...Auten LONG TERM...Auten AVIATION...MJA
Area Forecast Discussion...Updated
National Weather Service Saint Louis MO
937 PM CDT Thu Jun 24 2021 .UPDATE... Issued at 926 PM CDT Thu Jun 24 2021 The forecast looks basically on track at this point. Convection over northwest Missouri has developed into a QLCS which is moving east-southeast. There have been several reports of wind damage over northwest-north central Missouri associated with the bow on the northern end of the QLCS. The RAP continues to show 2500-3000 J/Kg and 30-40kts of 0-3km shear to continue to power the QLCS east into our forecast area over the next few hours. Forward propagating Corfidi vectors indicate the bow and overall QLCS should continue on a generally east-southeast course at least for the next several hours, if not for the remainder of the night. Expect wind in excess of 60 mph to continue to be the primary threat with the bow, but 0-1km bulk shear is 20-30kts so a brief tornado touchdown will also be possible. Carney && .SHORT TERM... (Through Late Friday Night) Issued at 240 PM CDT Thu Jun 24 2021 An MCV was located over west-central Illinois moving east/southeast, with more concentrated convection just downstream of this feature. Further south, weakening showers and storms are also drifting east across the bi-state area. There should be a lull behind the ongoing activity, with subsidence behind the departing MCV and lesser instability due to prior rainfall. Earlier runs of the HRRR developed convection very rapidly this afternoon along a surface trough axis, though has recently backed off at least in terms of timing. This makes more sense given the aforementioned subsidence aloft. While I am unsure how widespread storms will get early this evening across northeast Missouri and west-central Illinois along the surface trough axis, there is high confidence that the stronger low-level convergence will lead to widespread strong-severe storms across the mid-Missouri Valley late this afternoon into early this evening. These storms should move east/southeast as they get an organized cold pool through the overnight hours. Damaging wind gusts are the main threat, especially in central and northeast Missouri. As the storms progress further east/southeast, there are some signals that the line may become more outflow dominant. While an isolated tornado or two cannot be ruled out in central and northeast Missouri, the orientation (west to east) of the 0-3km shear vector should not be ideal for mesovortex genesis along the line. The heavy rainfall threat tonight looks to be more conditional on how quickly storms develop along the surface trough in northeast Missouri and west-central Illinois. These storms will have the propensity to train, but there remains uncertainty with not only how quickly they develop in our northern CWA, but also how widespread at least initially. Once the thunderstorms congeal more into a line and develop a cold pool, they should progress to the east/southeast at a decent clip which would lessen the chances of flash flooding. The bigger flash flood threat appears to be Friday afternoon and evening as thunderstorms redevelop the effective boundary or outflow boundary. The concern is more heightened is this period because of the high likelihood of training convection near this surface boundary in an environment very favorable for efficient rainfall (deep warm cloud depths, precipitable water values near daily records). In addition, antecedent conditions will likely be more supportive, as tonight`s rainfall will help prime conditions to produce more runoff with this second round of storms. The uncertainty is exactly where the west/southwest to east/northeast axis of heaviest rainfall will be Friday afternoon/evening. Used a blend of QPF, but did give a nod to the further south solutions of the Hi-Res NAM and 12Z HRRR. Given tonight`s expected evolution of storms, the effective frontal boundary will likely be further south than some of the other guidance. Past experience also favors a slightly further south solution. So, all that being said, the most likely areas for the heaviest rains tomorrow appears to be near a KMYJ to KPPQ line. Rainfall totals through Friday night of 2-4 inches are expected in/around these locations, with locally higher totals very likely. In fact, the latest HREF suggests much higher totals are possible looking after its probability matched mean 48- hour totals. With this package, updated the flash flood watch and expanded it slightly further to the south and east. In addition, it was extended in time through Friday night to cover tomorrow afternoon and evening`s second round of storms. Gosselin .LONG TERM... (Saturday through Next Thursday) Issued at 240 PM CDT Thu Jun 24 2021 A continued active pattern is expected through at least early next week beneath southwest flow aloft and a quasi-stationary front at the surface. The good news is forcing for ascent looks quite a bit weaker by late weekend/early next week, so widespread organized storms look less and less likely. However, by that time and rain at least for a good chunk of the area will not be welcomed. Temperatures are likely to be near normal during the day and above normal at night given the continued chances for rain and quite a bit of cloud cover. Gosselin && .AVIATION... (For the 00z TAFs through 00z Friday Evening) Issued at 638 PM CDT Thu Jun 24 2021 Primary concern for tonight is obviously thunderstorms. Current thinking is that the cluster of storms over the Mid Missouri Valley will grow upscale into a squall line that will surge southeast later this evening and overnight. There will likely be a few cells ahead of the line which could briefly produce MVFR/IFR visibility in moderate to heavy rain. The line itself will likely produce MVFR/IFR visibility as it moves through. Gusty winds are also possible, though I have not mentioned wind gusts in the TAFs just yet as I would prefer to get a better handle on timing. Moderate to occasionally heavy rain will likely persist in the wake of the line over parts of central and northeast Missouri which could keep lower visibility in those areas...again, would like to see some continuity of observations behind the line before forecasting low visibility all night. Rain and thunderstorms should diminish Friday morning after 12Z. Another round of storms looks likely Friday afternoon/evening. SPECIFICS FOR KSTL: The line of storms mentioned above will likely impact Lambert between 07-09Z. Until then, expect VFR flight conditions to prevail. There is a great deal of uncertainty about what will happen after the initial wave of storms. It`s possible that moderate to heavy rain will continue at the terminal through the early morning until 12-15Z. Have taken the more optimistic solution of the storms blowing through with rain tapering down to occasional showers Friday morning...but again, I`m not terribly confident in this outcome. Carney && .LSX WATCHES/WARNINGS/ADVISORIES... MO...Flash Flood Watch through Saturday morning for Audrain MO-Boone MO-Callaway MO-Cole MO-Franklin MO-Gasconade MO-Knox MO- Lewis MO-Lincoln MO-Marion MO-Moniteau MO-Monroe MO- Montgomery MO-Osage MO-Pike MO-Ralls MO-Saint Charles MO- Saint Louis City MO-Saint Louis MO-Shelby MO-Warren MO. IL...Flash Flood Watch through Saturday morning for Adams IL-Brown IL- Calhoun IL-Greene IL-Jersey IL-Macoupin IL-Madison IL- Montgomery IL-Pike IL. && $$ WFO LSX
Area Forecast Discussion
National Weather Service Newport/Morehead City NC
1010 PM EDT Thu Jun 24 2021 .SYNOPSIS... A boundary stalled off the North Carolina coast will move back onshore as a warm front tonight into Friday. High pressure then builds back into the area this weekend. && .NEAR TERM /Through Sunrise Friday/... As of 1010 PM Thu...Cont trend of wetter and higher rain totals through Fri am. Lower atms cont to moisten as WAA aloft strengthens, with veering wind profile evident on KMHX VAD wind profile. Last several runs of the HRRR and latest 25/00Z NAM indicate good moisture flux, PW`s approaching 2", and fairly strong low level frontogenesis peaking around 12Z as coastal trough/front comes ashore. Some higher QPF of over an inch will fall locally, and have inc QPF to 0.5"+ for coastal counties. Prev discussion... As of 630 PM Thu...Clouds from offshore rapidly expanding towards and over the coastal counties early this evening. Even some light shra breaking out across the srn waters and moving onshore over srn Onslow and Pender County. Have sped up arrival time of sct showers to the coast as a result. Latest 24/18Z guide indicating greater than sct covg of showers by 12Z for coastal areas, and have inc pops to low end likelies, expanding inland through the morning hours. Avg QPF should be less than 0.5", but high res guide indicating some heavier convective elements producing amts over 1.0", certainly plausible given good moisture convergence with coastal front and high pwats advecting into E NC. Prev discussion... As of 245 PM Thu...Quasi- stationary offshore boundary will slowly creep inland tonight into early Friday morning. Better moisture convergence along the front will produce some sct showers and possibly an iso tstorm. Hi res guidance showing some better instability behind the front, providing a better chc for a sct tstorm come daybreak, esp for the coastal areas. Inched lows down a degree or two, bringing low to mid 60s inland with upper 60s to around 70 along the coastal areas. && .SHORT TERM /FRIDAY/... As of 255 PM Thu...Frontal boundary will move further inland during the day and bring sct to numerous showers with a chance for tstorms as well. Hi res guidance showing modest CAPE values in the wake of this front, around 500-1000 J/kg, and PWAT values over 2 inches, providing enough instability and moisture to fuel some tstms within the warm side of the front. Virtually no shear will prevent much severity with these storms, however. Kept POPs to a high-end chance, since coverage could be questionable. Guidance shows a few breaks in the cloud deck potentially by the aftn, which would help raise temps and trigger some additional convection. Aftn highs expected to reach the mid 80s all around with most of the area behind the warm side of the front by midday. Dewpoints will return back to the low to mid 70s once again with Srly. Front begins to dissipate by Friday night, diminishing shower coverage in the evening. A few sct light showers remain possible overnight, especially along the Crystal Coast. Overnight lows around 70 inland with mid 70s along the coastal areas. && .LONG TERM /FRIDAY NIGHT THROUGH THURSDAY/... As of 320 AM Thursday... For the weekend into the middle of next week, mid-level high pressure expands west from the Atlantic as the Bermuda ridge sets up at the surface. Weak daily trough will occur over the Piedmont. Precipitable water values remain at or above 2 inches through midweek. This combination of factors will produce a daily threat of scattered showers and thunderstorms and have PoPs in the climatologically normal 30-40 percent, mainly inland through the period. High temperatures climb from the mid 80s over the weekend, into the upper 80s Monday through Wednesday. && .AVIATION /02Z FRIDAY THROUGH TUESDAY/... SHORT TERM /through 18Z Friday/... As of 630 PM Thu...VFR conditions expected through the evening before a stalled offshore boundary slowly retrogrades inland overnight and into Friday. Expecting cigs to begin lowering late this evening and overnight, beginning with terminals closest to the coast and spreading inland. Expect MVFR ceilings after midnight into the early morning hours dropping to IFR prior to or around sunrise. Expect ceilings to lift back to MVFR around 14Z, improving to VFR by the aftn. Sct showers early in the morning become numerous through the morning hours into early aftenroon, with embedded thunder also possible esp mid morning and beyond. LONG TERM /Friday afternoon through Monday/... As of 320 AM Thursday...A frontal boundary slips moves onshore early Friday. Given high precipitable water values, scattered to numerous showers are likely, especially early Friday, with a few thunderstorms possible as well. This will produce some sub- VFR conditions Friday. For Saturday through Monday, a more typical summer regime is likely with scattered showers and storms along the sea breeze in the afternoon and evening hours. Some patchy fog may occur at night bringing brief reductions in vsby. && .MARINE... SHORT TERM /Tonight and Friday/... As of 320 PM Thu...Still some breezy conditions over the waters late today, but gradual improvement continues into Friday as the coastal front pushes inland. NE winds 10-15 kts with gusts up to 20 kts tonight will veer SE around 10 kts with gusts up to 15 kts behind the front. A few tstorms can be expected as the front passes through overnight and into Friday. Seas will stay around 3-4 ft. LONG TERM /Friday night through Monday/... As of 325 AM Thursday...With high pressure at the surface and aloft building west from the Atlantic through the period, a fairly consistent pattern develops. Expect SE winds 10-15 knots and seas 2-4 feet for the most part through the extended period. Small Craft Advisory conditions are not expected. && .MHX WATCHES/WARNINGS/ADVISORIES... NC...Beach Hazards Statement from 8 AM EDT Friday through Friday evening for NCZ196-203>205. MARINE...None. && $$ SYNOPSIS...MHX NEAR TERM...TL/ML SHORT TERM...ML LONG TERM...CTC AVIATION...CTC/TL MARINE...CTC/ML
Area Forecast Discussion
National Weather Service Marquette MI
813 PM EDT Thu Jun 24 2021 .SHORT TERM...(This evening through Friday) Issued at 341 PM EDT THU JUN 24 2021 A cold front continues to work its way through the western U.P. As of 3 PM, winds have now gone NW in places like Kenton, Sidnaw, and Watersmeet, and remain between SE and SW at SAW, IMT, and ESC. SPC Mesoanalysis shows most of the central U.P. with 1000-1500 J/kg MLCAPE, but MLCIN persisting except over the Michigamme Highlands. Given the widespread cloud cover over the pre-frontal sector, it makes sense that there would still be MLCAPE left to erode. HRRR soundings also show a pretty substantial cap in the 800-700 mb layer. Therefore, convection has been slow to get going, and the overall trend is towards less coverage and lower intensity. Still, CAMs are adamant that storms will form along the front over the central U.P. in the next couple of hours and gradually sink south this evening. With instability ending up on the low side of what was forecast, and effective shear somewhat marginal (around 35 kts) most storms that do form will be pulsey and pose only a risk for marginally severe hail/wind. Have downplayed the severe risk in the HWO with the afternoon update and trimmed back POPs. Tonight, the front will continue to sag south and east across the area with showers continuing over the eastern U.P. Some storms will remain possible as well, but overall CAPE will be decreasing with the loss of whatever daytime heating there has been so far. Over the west half, expect skies to clear behind the front. Temps should cool off nicely into the low to mid 50s for lows. With the moisture around from this morning`s thunderstorms, some patchy ground fog will likely result late tonight. Elsewhere, where cloud cover will remain thicker along and ahead of the front, went much warmer with lows. Temps may not get below 60 for much of the central and east. If enough rain falls over Lake Superior, there could be a patch of marine fog that forms as well and is then advected onshore by light NE winds behind the front. That could lead to thicker fog along the Lake Superior shoreline, especially around Marquette, but is contingent on enough rain falling over the lake. Tomorrow, the front will only make it as far east as the eastern U.P. By this point, the temperature gradient will be almost completely inverted, with sunny skies on the west/"cool" side of the front and thick cloud cover persisting east. Therefore, look for highs in the upper 70s to around 80 interior west and in the mid 70s east. Strenghtening NE flow will advect lake-cooled air onshore and keep temps cooler north, especially right along the immediate Lake Superior shoreline where temps may not get out of the 60s for highs. .LONG TERM...(Friday night through Thursday) Issued at 249 PM EDT THU JUN 24 2021 Upper air pattern consists of a 500 mb trough in the northern and central plains 00z Sat which drops into the upper Great Lakes and remains through 00z Mon. Latest model trends continue to take things further to the south and east and the highest pops will be in the south and eastern cwa for this forecast period. Otherwise, no big changes made to the going forecast. In the extended, the GFS and ECMWF show a deep 500 mb trough over the upper Great Lakes to the central plains with a ridge in the western U.S. and a ridge on the east coast 12z Mon. This trough remains over or near the area and moves little through Thu. Temperatures will remain near normal and will be unsettled with upper troughing in the area. && .AVIATION...(For the 00Z TAFS through 00Z Friday evening) Issued at 813 PM EDT THU JUN 24 2021 A weak cold front across central Upper MI will continue drifting e tonight. In the wake of the front at KIWD/KCMX, expect VFR conditions to prevail thru this fcst period. However, mostly clear skies and light winds tonight may result in some shallow radiation fog developing. KCMX probably has a better chc of seeing some fog, but for now, fcst will only reflect MVFR conditions due to uncertainty. At KSAW, expect the possibility of shra into the overnight hrs with the front in the vcnty. MVFR cigs should also prevail thru the evening. Overnight, expect fog to develop, dropping conditions to LIFR. It`s possible conditions could fall blo airfield landing mins, but right now, that appears unlikely. Expect improvement to VFR during the morning. && .MARINE...(For the 4 PM Lake Superior forecast issuance) Issued at 353 PM EDT THU JUN 24 2021 Light winds generally 15 kts or less are expected throughout the forecast period across the lake. Some thunderstorms are possible this afternoon and evening over the eastern half of the lake. Along with moist air ahead of an approaching weak cold front, these showers and storms will probably lead to fog development tonight over the eastern half of the lake. While some fog could be locally dense, opted to go without dense wording in the forecast for now. With weak winds and the front slow to clear the area, this fog will likely persist through Friday and could even persist into Saturday. However, confidence after Friday evening is lower, so it has been left out of the forecast for now. && .MQT WATCHES/WARNINGS/ADVISORIES... Upper Michigan... Beach Hazards Statement until 10 PM EDT this evening for MIZ014. Lake Superior... None. Lake Michigan... None. && $$ SHORT TERM...RJC LONG TERM...07 AVIATION...Rolfson MARINE...RJC
Area Forecast Discussion
National Weather Service Springfield MO
917 PM CDT Thu Jun 24 2021 .UPDATE... Issued at 917 PM CDT Thu Jun 24 2021 Ongoing thunderstorms from northern Missouri into northeast Kansas will likely shift/develop more east southeast as the evening wears on. The low level jet over Kansas is beginning to strengthen feeding into this complex with nice area of convergence seen in meso analysis over Kansas and this will continue to fuel these storms overnight. 18Z NAMNest is most robust with its southeast movement bringing the activity into our central Missouri counties towards midnight. HRRR on the other hand is keeping much of the activity just north of the area. Will continue to monitor how far south these can get overnight, but certainly our far northern counties will be the ones under the gun. The storms will likely evolve into an organized linear mode with bowing segments as the night wears on. Based on current radar trends across northeast Kansas did raise wind speed potential to 60 to 70 mph. In addition, heavy rainfall a concern with high precipitable water values expected. 00Z TOP sounding shows PWs of 2.01 inches. && .SHORT TERM...(This evening through Friday) Issued at 236 PM CDT Thu Jun 24 2021 Thunderstorm complex from this morning has dissipated to mainly light showers over central MO. Extensive cloud cover remains however and has limited temperatures rises there with readings still in the mid to upper 70s. Further southwest, we did clear out and temperatures rose in the the lower 90s. Dew points have risen from yesterday into the low to mid 70s, which was bringing some heat index values into the upper 90s into the lower 100s. Instability increased over southeast Kansas and southwest MO with a few storms developing over southeast Kansas. Storms were beginning to fire again in east central KS in an area of higher instability near the edge of the thermal cap. This activity may move into the central MO counties late this afternoon and evening. Further northwest, robust convection is expected to develop and form into another thunderstorm complex. The main areas this will affect will be central MO into west central MO and southeast Kansas. Damaging wind and large hail will be the main severe weather risks with torrential rainfall accompanying the storms as PW values will be from 1.75 to 2.0 in. Despite the recent lack of rainfall over the area, repeat heavy rain over the same locations may lead to some localized flooding. The bulk of the heavy rain should remain north of the forecast area. The severe weather and heavy rain risk will linger into Friday as the MCS drifts east across the northern portions of the CWA. Additional convection will then be redeveloping over southeast Kansas into central MO as the instability increases in the wake of the MCS. For those areas which can clear out and warm up, another day with heat index values in the 100 to 105 degree range will be possible. Depending on how the system evolves tonight, we might need to eventually go with a flood watch for later convection. .LONG TERM...(Friday Night through Thursday) Issued at 236 PM CDT Thu Jun 24 2021 The continued risk of showers and thunderstorms with heavy rain will linger through the weekend and into the middle of next week as an upper trough remains positioned to the west of the area. A front will be slow to move through the area and we will see several rounds of convection through the period. Highs will generally be in the 80s with lows in the 60s. && .AVIATION...(For the 00Z TAFS through 00Z Friday evening) Issued at 621 PM CDT Thu Jun 24 2021 VFR flight conditions will for the most part be the rule through the TAF period with mainly mid and high level clouds being the rule. Will continue to see rather breezy conditions with south to southwest winds gusting to 20 to 25 knots at time, especially at KSGF and KJLN. In addition a low level jet will nose into western Missouri late tonight with low level wind shear likely developing at KJLN. Late this afternoon storms were developing over far northern Kansas and southern Nebraska. These will likely begin to move south and east overnight, possibly getting into central Missouri before dissipating or sliding east. Did add some VCSH to KJLN and KSGF between 13Z- 17Z Friday for any stray showers that may make it that far south. However, confidence rather low as better convective chances reside well north of the TAF sites. && .SGF WATCHES/WARNINGS/ADVISORIES... MO...NONE. KS...NONE. && $$ UPDATE...Raberding SHORT TERM...Lindenberg LONG TERM...Lindenberg AVIATION...Raberding