Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 06/22/22

Area Forecast Discussion
National Weather Service Cleveland OH
926 PM EDT Tue Jun 21 2022 .SYNOPSIS... A ridge of high pressure will weaken tonight allowing a cold front to sink across the region Wednesday. High pressure will build in behind this front Wednesday night and remain in control through the start of the weekend. && .NEAR TERM /THROUGH WEDNESDAY NIGHT/... Update... Forecast remains on track. No changes appeared necessary late this evening. Latest hi-res model guidance continues to suggest minimal potential for showers and thunderstorms to accompany the cold front as it approaches from the northwest and nears the major axis of Lake Erie and our far-northwestern OH counties around daybreak tomorrow morning. It appears a lack of stronger low-level convergence along the front and moderate to excessive boundary layer CIN, including surface-based CIN, should prevent convection initiation despite the expectation for MUCAPE to build to moderate to strong magnitudes overnight tonight as low-level WAA and moisture advection occur in the warm sector. Previous Discussion... The main story late this afternoon through tonight is the heat and increasing humidity as an expansive mid/upper ridge remains anchored over the TN Valley. H5 heights in the center are 595-597 DM over the TN Valley, with H5 heights of 591-594 DM extending north across the lower Great Lakes. These heights, along with 850 mb temps averaging 20-21 C across the region and full sunshine due to the strong subsidence beneath the ridge, have allowed temps to warm into the upper 90s in NW Ohio, mid 90s in north central and NE Ohio, and upper 80s in NW PA. Visible satellite loops do not show any cumulus development, and this is due to both a strong mid-level cap analyzed in the latest RAP forecast soundings and CAPE values limited by dew points only in the 55-60 range. A mid/upper shortwave trough, currently located over North Dakota, will progress into the Upper Great Lakes tonight and begin to flatten the ridge. This trough will be weakening as it runs into the strong ridging, and the associated surface low will pass well north into Hudson Bay. This will lead to a weak cold front settling south through the Midwest and central Great Lakes tonight. Increasing warm/moist advection ahead of the boundary will finally bring dew points up into the 65-70 range tonight, and this along with the hot antecedent conditions will hold lows in the low/mid 70s leading to a warm, muggy night. The aforementioned cold front looks to cross Wednesday morning into early afternoon. This early timing, along with limited shear and upper forcing displaced so far north, will keep any isolated severe convection confined to far southern areas Wednesday afternoon from about Mt Vernon to Marion. A few showers and isolated thunder will develop along the frontal boundary over the lakeshore counties Wednesday morning, before pushing inland during the early afternoon, but the limited forcing will lead to isolated to only widely scattered coverage. HREF CAMS have caught onto this thought process and now generally show new convective development south and southeast of our CWA Wednesday afternoon, so it`s possible that we don`t see any severe weather at all. However, MLCAPE is progged to exceed 3000 J/Kg by early afternoon with over 4500 J/Kg of SBCAPE, and steep low-level lapse rates of 8.5 to 9 C/Km, dry mid-levels characterized by RH below 60%, and DCAPE of 1050-1200 J/Kg all could lead to isolated severe downburst/wet microburst pulse type convection. For this reason, the latest SWODY2 keeps a marginal risk from a line just north of Meadville to north of Mansfield. Any thunderstorm will also contain locally heavy rain since mean winds in the mid-levels will only be around 17 knots leading to slow storm motions of 10 knots or less, and this combined with seasonably high PWATs of 1.7 to 2.0 inches, deep warm cloud depths, and relatively skinny CAPE profiles all support localized torrential rainfall. The best chance for this will again be in far southern areas. Highs Wednesday will warm into the upper 80s to mid 90s (highest in NW Ohio), but greater cloud cover will keep heat indices below criteria. Any showers/storms will exit quickly Wednesday evening leading to dry conditions Wednesday night as mid/upper troughing skirts across the Great Lakes and surface high pressure builds in from the Upper Midwest/western Great Lakes. This will allow cooler, drier air to filter into the region, so lows will drop into the upper 50s to mid 60s. && .SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... An upper level ridge building east over the area during this forecast period should continue to bring fair weather to the forecast area. The upper level ridge will result in surface high pressure that is expected to remain nearly stationary Thursday through Friday night over the forecast area. Although, a weak surface trough is expected to move southeast across the region Wednesday night. The cold air advection in advance of the surface high pressure should keep temperatures in the middle to upper 70s across the east and lower to middle 80s in the west Thursday. Light winds by Thursday night will allow for radiational cooling to take place and drop lows into the 50s east and around 60 west. Subsidence takes place Friday allowing temperatures to jump back into the middle and upper 80s for highs by Friday and lows Friday night into the upper 50s east to middle 60s west. && .LONG TERM /SATURDAY THROUGH TUESDAY/... An upper level ridge shifts east of the area during this period forcing the surface high to move east off the New England Coast by the weekend. A return southerly flow develops and with it warm air advection heading into the weekend. Models suggest an upper level trough should move east across central Ontario, Canada by Sunday forcing a weak area of low pressure to move east as well. The low will force a cold front east across the forecast area Sunday along with a swath of moisture. Instability and warming ahead of the cold front should support a threat for showers/thunderstorms across the area with the frontal passage. Cold air advection follows the cold front Sunday night into Monday. Another weak upper level ridge is progged to move east into the area Monday night into Tuesday forcing a surface high to build east across the area. QPF amounts look to be rather light with the cold frontal passage at this time. Otherwise, expect warming to take place Saturday through Sunday followed by cooler temperatures into early next week. && .AVIATION /00Z Wednesday THROUGH Sunday/... A surface cold front should sweep southeastward across our region between ~12Z and ~18Z/Wed and will be flanked by surface high pressure. Southwesterly regional surface winds around 5 to 15 knots veer to northwesterly following the front`s passage. Primarily VFR are expected through the period. However, isolated showers and thunderstorms are possible along and in vicinity of the front, especially south of the latitude of KMFD and between ~15Z and ~21Z/Wed. This convection may be accompanied by brief MVFR to LIFR in heavy rainfall and brief/erratic surface gusts up to 50 knots. Outlook...Non-VFR possible in isolated showers and thunderstorms Wednesday evening and again on Sunday. && .MARINE... Westerly flow should become more northerly by Wednesday afternoon as a cold front moves across the area Wednesday. Northerly flow will persist into Thursday and then become light and variable by Friday as high pressure builds east across the area. The high pushes east of the area over the weekend and a return southerly flow, albeit light, develops by Saturday. Winds should increase Saturday night into Sunday as a cold front sweeps east across the lake. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...None. PA...None. MARINE...None. && $$ SYNOPSIS...Garuckas NEAR TERM...Garuckas/Jaszka SHORT TERM...Lombardy LONG TERM...Lombardy AVIATION...Jaszka MARINE...Lombardy
Area Forecast Discussion
National Weather Service State College PA
1055 PM EDT Tue Jun 21 2022 .SYNOPSIS... Summertime heat and humidity arriving on schedule will increase into midweek, fueling a risk of severe thunderstorms and flooding downpours on Wednesday. Showers could linger over eastern Pennsylvania early Thursday, but the overall precipitation trend will be drying out with lower humidity for late week. The last weekend of June 2022 should start off dry before showers and thunderstorms likely return on Sunday. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/... Satellite imagery this evening is showing mainly clear skies across central Pa in region of upper level ridging and low pwats. Some model guidance indicates the chance of late night showers associated with a weak shortwave cresting the ridge and the return of higher pwats. However, a lack of upstream convection over southern Ontario, as well as the latest HRRR and 12Z HREF, suggest dry weather is likely overnight. Low temperatures should range from the mid to upper 60s over much of the forecast area. However, min temps closer to 60F appear likely over the eastern edge of the forecast area on the cool side of a stalled warm front. && .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/... Wednesday continues to shape up to be a potentially active wx day across CPA with both WPC and SPC upgrading the ERO and SWO categorical risk levels from MRGL to SLGT. Falling heights ahead of a shortwave diving through the Grt Lks, combined with heating of moist/unstable air mass over western and central Pa, should result in developing convection during the afternoon. In general, model soundings are pointing toward a high cape/low shear environment, supportive of isolated severe weather during the PM hours. However, increased shear in vicinity of a stalled warm front should support more sustained updrafts and a correspondingly greater threat of severe weather in that area. There is some model spread/forecast uncertainty where this north/south boundary will be, but ensemble mean suggests it will run from Potter or Tioga Co in the north, to Fulton or Franklin in the south. A cooler, more stable air mass east of the front should result in a diminished threat of severe weather in that part of the state. An environment of high CAPE in excess of 2000 J/kg, combined with high pwats of around +2SD above climo, could also result in locally excessive rainfall and flooding. Latest FFG is fairly high, but convection-allowing models indicate spot amounts of 3-4 inches are possible in the vicinity of the stalled front, so flash flooding is possible in this area. MaxTs Wednesday should range from around 80F over the eastern edge of the forecast area on the cool side of the front, to near 90F in the deeper valleys across the western half of the state. Expect dwindling convection Wednesday night, as backdoor cold front pushes through the western counties. However, passage of mid level shortwave will keep the chance of showers going, especially over the eastern counties, where the deepest moisture will lie. In between any showers model soundings support patchy drizzle due to an upsloping southeast flow and a nearly saturated 0-1km layer. && .LONG TERM /THURSDAY THROUGH TUESDAY/... Model soundings still support morning stratus and patchy drizzle over much of the forecast area Thursday. Hoever, large scale subsidence behind exiting shortwave should bring brightening skies by afternoon. All guidance supports fair weather Friday and Saturday, as surface high builds east into the region. Model 850mb temps support seasonable temperatures Friday, then a warmer return southwest flow is likely Saturday, as surface high slips off the east coast. Heat and humidity notch up Sunday ahead of an approaching cold front, which should be accompanied by a good chance of convection Sunday PM based on latest ensemble plumes. Lingering convection is possible Monday (mainly southeast Pa), depending on timing of the front. Medium range guidance then supports a fairly high confidence of fair and cool conditions Monday night into Tuesday associated with the arrival of high pressure. && .AVIATION /03Z WEDNESDAY THROUGH SUNDAY/... A north/south oriented front remains nearly stationary across central PA tonight. Low level moisture is limited on the west side of the front, and slightly higher to the east. Most locations will be VFR tonight, but some vsby restrictions in BR/FG can`t be ruled out in the lower Susq late tonight. For Wednesday, numerous showers and some thunderstorms look likely for at least a portion of central PA. Rain looks most likely at UNV, closest to the N-S oriented boundary. Some low clouds and vsby restrictions will be possible Wed evening on the east side of the front. Outlook... Thu...Mainly VFR. Isolated SHRA SE. Fri-Sat...Mainly VFR. Sun...Mainly VFR. Chance of a shower or storm, mainly late. && .CLIMATE... Astronomical summer (solstice) begins at 5:14 A.M. EDT today. The summer season duration is 93 days, 15 hours, and 50 minutes before the Fall Equinox on September 22, 2022 at 9:04 P.M. && .CTP WATCHES/WARNINGS/ADVISORIES... None. && $$ SYNOPSIS...DeVoir/Steinbugl NEAR TERM...Fitzgerald SHORT TERM...Fitzgerald/Steinbugl LONG TERM...Fitzgerald/Dangelo AVIATION...Martin/Colbert CLIMATE...
Area Forecast Discussion
National Weather Service Dodge City KS
1045 PM CDT Tue Jun 21 2022 ...Updated Aviation... .SHORT TERM...(This evening through Wednesday) Issued at 400 PM CDT Tue Jun 21 2022 This afternoon`s water vapor loop and RAP analysis showed that the North American Monsoon circulation was well-established, extending from northern Mexico through southeastern Arizona and much of New Mexico...up northeast through eastern Colorado and adjacent western Kansas. At the surface, a weak front pushed and became stationary between Dodge City and Garden City. Thunderstorms developed mid afternoon in vicinity of the frontal zone once convective temperature was reached. Thunderstorms will be sub-severe for the most part, although we will need to watch the eastern counties where SBCAPE is a bit higher, although even across the eastern counties the CAPE isn`t all that high. Much better low level moisture was across central and south central KS. We will maintain some 40-50 POPs across much of the southwest Kansas region, with Likely POPs up around Hays, closer to the better low level moisture later tonight. The front will make another push south tonight and eventually stall out again on Wednesday farther south than this afternoon`s position. Post-frontal easterly upslope flow will draw in better low level moisture across southwest Kansas, setting the stage for a better thunderstorm opportunity across our region. .LONG TERM...(Wednesday night through Tuesday) Issued at 400 PM CDT Tue Jun 21 2022 Thursday and Friday will be the hottest days of the Long Term period ahead of the next strong cold front due in later Saturday. Friday may very well be the hottest day of the young summer season so far for much of southwest Kansas with widespread high temperatures of 103 to 106 likely. As mentioned by the previous shift, it would not be too surprising if Dodge City topped 105F if the best downslope momentum plume noses northeast right across Dodge. Timing of the cold front on Saturday will present a temperature forecasting challenge, as frontal passage will most likely occur earlier in the day than previous forecast. The official high temperature for Saturday at DDC is 93, but this may need to be lowered if the forecast front timing continues to be earlier in the morning. An anomalously cool airmass by late June standards will drive south across the Central Plains, supporting much cooler surface temperatures Sunday. The latest NBM guidance came in this afternoon with a high of only 78F at Dodge City for Sunday. Much like today and tomorrow, the monsoon circulation will become infused with the weekend frontal system, leading to another good chance for rain across our region. The NBM POPs have been increased to 40-50 percent across much of southwestern Kansas given the greater agreement among global spectral models and their ensemble members. The cool airmass will continue through early next week before slowly modifying by around Tuesday of next week. && .AVIATION...(For the 06Z TAFS through 06Z Wednesday night) Issued at 1045 PM CDT Tue Jun 21 2022 Midlevel cloud decks will persist for most of this TAF cycle, with a plume of monsoonal subtropical moisture spreading over SW KS. Ceilings will average in the 9-12k ft AGL range. Scattered rain showers may redevelop as early as Wednesday morning, but have higher confidence of another round of scattered thunderstorms after 18z Wed. Much like yesterday, confidence of direct convective impacts at any terminal is low, so again only included a VCTS/CB mention for now. Winds will be light this TAF cycle, with light north winds currently, gradually trending SEly Wednesday afternoon. Winds are expected to remain generally less than 10 kts. && .PRELIMINARY POINT TEMPS/POPS... DDC 65 88 66 98 / 70 40 30 10 GCK 65 87 65 98 / 30 40 30 10 EHA 62 88 64 96 / 30 40 30 10 LBL 66 90 65 98 / 30 30 30 0 HYS 67 85 67 95 / 30 30 30 30 P28 70 91 70 98 / 30 30 20 0 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...Umscheid LONG TERM...Umscheid AVIATION...Turner
Area Forecast Discussion
National Weather Service Goodland KS
506 PM MDT Tue Jun 21 2022 .SHORT TERM...(This evening through Thursday) Issued at 327 PM MDT Tue Jun 21 2022 At the beginning of the short term period, the latest RAP analysis shows the CWA with a southwesterly flow aloft being between a positively tilted trough in the west and a positively tilted ridge in the east. Current satellite imagery shows a good amount of cloud cover over the entire CWA with radar data showing hit or miss light rain showers going across the CWA from Cheyenne Wells up northeast through McCook and beyond. Forecast guidance continues to depict the southwesterly flow over the CWA throughout the day with an upper air high starting to move over OK/TX. At the surface, spotty light rain showers look to be possible particularly in the along and east of the area line mentioned previously. Convective parameters for the remainder of the day do not support any severe weather with very little CAPE and shear. The overcast skies look to continue through the night hours as well. Daytime highs look to range between the upper 70s and the upper 80s followed by overnight lows in the middle 50s to middle 60s. On Wednesday, forecast models show the CWA`s upper air flow turning west-southwesterly in the morning as an upper air ridge builds in the central CONUS throughout the day due to the OK/TX upper air high. A shortwave disturbance is seen passing over the CWA during the evening hours. At the surface, there looks to some chances for showers and thunderstorms during the day. CAPE values look to be a bit better than those on Tuesday around 1000 J/kg in the afternoon and evening in spots though 0-6m shear values still appear to be low around 10-20 kts. As mentioned in the previous discussion: cloud cover through might hinder even these prospective convective parameters, so this will be monitored going forward in case the trend starts favoring severe weather. Wednesday`s daytime highs expect to be in the lower to middle 80 with overnight lows in the middle 50s to middle 60s. For Thursday, the west-southwesterly flow looks to continue over the CWA being underneath ridge throughout the day with shortwave disturbances traveling through during the evening. A closed upper air low over CA begins to open up into a trough during the day and progress eastward with another low well north of it moving over southern BC. At the surface, there looks to be a warm front passing through during the day that will warm temperatures. There looks to be chances for showers and thunderstorms for areas east of the CO border with the potential for some possible severe weather though the specifics still look to be a little uncertain at this time. Forecast model soundings continue to show some possible up to SBCAPE of 2000 J/kg with 0-6 km shear values around 30 kts. Daytime highs for Thursday look to be in the lower to upper 90s followed by overnight lows in the upper 50s to lower 70s. .LONG TERM...(Friday through Tuesday) Issued at 207 PM MDT Tue Jun 21 2022 A brief break from the heat expected over the weekend as strong cold front remains on track to sweep across the region Friday night and early Saturday morning with strong overall model consensus on this pattern change. Net result will be temperatures nearly 20 degrees cooler on Saturday, with even cooler conditions on Sunday. Temperatures will gradually climb back into the 90s by the middle of next week. While confidence is high in frontal passage and resulting impact on temperatures, precipitation chances remain unclear. With strong forcing along front, Friday night would seem to be the best chance for organized precipitation but have a lot of concerns about potential instability/moisture availability ahead of advancing front, as sfc fields suggest CWA will be behind dryline as front approaches. While think the calibrated probabilities in the 40-60 percent range are reasonable, have doubts if there will be much meaningful precipitation during the period. Threat for afternoon and evening storms will continue through the start of the week as easterly sfc flow will potentially bring moist return flow to the area, with overall synoptic pattern being favorable for ascent due to proximity of entrance region of H3 jet. Scenario and potential for meaningful precipitation will strongly be tied to quality of moisture return advecting to the west around sfc high. If airmass is drier than expected, precipitation coverage and amounts will diminish quickly. && .AVIATION...(For the 00Z TAFS through 00Z Wednesday evening) Issued at 459 PM MDT Tue Jun 21 2022 VFR conditions are expected throughout the duration of the period. A SW to NE oriented band of showers is expected to slowly move east through the evening. Broken to scattered skies will continue overnight with light and variable winds. Winds will become SSE and breezy mid morning Wednesday with gusts up to 25 knots at each site. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...076 LONG TERM...JRM AVIATION...Trigg
Area Forecast Discussion
National Weather Service Green Bay WI
918 PM CDT Tue Jun 21 2022 Updated aviation portion for 06Z TAF issuance .SHORT TERM...Tonight and Wednesday Issued at 232 PM CDT Tue Jun 21 2022 A cold front was moving through north central and central WI this afternoon, accompanied by a wind shift to the west. Temperatures were warming into the lower to middle 90s ahead of the front, and dew points in the lower to middle 70s were pooling near the boundary. This was resulting in heat indices in the middle 90s to lower 100s over the Heat Advisory area. These will likely go up a couple degrees over the next couple hours. Despite the arrival of the cold front and MUCAPE of 2500-3500 j/kg, the combination of capping in the 850-800 mb layer, weak/shallow convergence, and minimal upper level support was preventing convective initiation. Our local meso-analysis page showed CINH decreasing to 25-50 j/kg near the front, so suspect isolated to scattered thunderstorms will eventually develop in NE/EC WI later this afternoon, as depicted by the HRRR and RAP. With DCAPE values of 1100-1400 j/kg and PWATS of 1.5-1.75 inches in place, could certainly see localized damaging winds and heavy rainfall with the stronger storms. However, hail would not appear to be as great a threat, given marginal deep layer shear (20-25 kts) and wet-bulb zero heights of 12.5-13K feet. The convection is expected to push out over Lake Michigan by around 02z/Wed. Cooler and much less humid weather will move into the area overnight and into Wednesday, along with moderate west to northwest winds. Lows tonight should be in the upper 50s to middle 60s. Highs on Wednesday should reach the 70s to lower 80s. .LONG TERM...Wednesday Night Through Tuesday Issued at 232 PM CDT Tue Jun 21 2022 The main highlights for the extended period will be the above normal temperatures from the end of the work week to the early weekend, along with a couple chances for active weather. Surface high pressure will start off the extended period Wednesday night, keeping dry conditions in place across the region through most of Thursday. Winds will turn to the southwest over the course of the day Thursday, which will bring back some very warm temperatures in the middle to upper 80s for the afternoon highs. Unlike today however, dewpoints will remain in the 50s, so the overall humidity will be much lower. As we go from Thursday night to Friday morning, high pressure will move off to the east allowing a weak shortwave to bring a few showers to the area. This will mainly impact northwestern and north- central Wisconsin. Not all the models have this feature at this time, as a few keep high pressure a little further west, which would keep most of our neck of the woods dry. The rest of Friday will also see weak WAA aloft and fairly strong surface heating. This could allow for a few more chances of precipitation in the afternoon to evening as some modest instability develops. Soundings at this time look tall and skinny with minimal shear, which could support isolated thunder but doesn`t look like the strongest setup for severe at this time, especially with the discrepancy on the shortwave still present. Still, kept some minimal pops in for Friday. While one eye will be kept on Friday, the other eye will be watching Saturday, which may be the better day for storm development. Again we get a strong push of warm air aloft, this time accompanied with some better PWATs, pushing 2+ inches of precipitable water across much of the region by the afternoon. As instability increases during the afternoon, a more definitive cold front will cross the region as a focal point for any developing convection. Shear profiles are also a touch more favorable. All that said, the better parameters will still be to our southwest. There will also be a big question on how many showers are still in the region early in the day from anything that happens Friday. So overall, the best chance for more widespread weather is still Saturday afternoon, but the overall severe potential remains in question at this time. High pressure then moves back in behind the cold front, bringing in quiet weather for the remainder of the extended. Temperature wise, a steady increase in temperatures is expected Thursday and Friday, with highs bordering the 90s. Temperatures will still be in the high 80s Saturday due to rain potential, but then make their way back into the 70s at the end of the weekend into early next week. && .AVIATION...for 06Z TAF Issuance Issued at 918 PM CDT Tue Jun 21 2022 A cold front drifting through the area early in the TAF period may lead to an isolated thunderstorm at the ATW/GRB/MTW TAF sites, while much of the rest of the area will remain dry. Winds will shift to the west-northwest as the front passes. Some LLWS will be possible across the central WI TAF sites overnight; otherwise, good flying conditions expected through the rest of this TAF issuance. && .GRB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM.....Kieckbusch LONG TERM......Uhlmann AVIATION.......Cooley
Area Forecast Discussion...Updated Aviation
National Weather Service Saint Louis MO
1040 PM CDT Tue Jun 21 2022 .SHORT TERM... (Through Late Wednesday Afternoon) Issued at 234 PM CDT Tue Jun 21 2022 A cold front is moving southeast through Iowa into northern Missouri this afternoon. The front is expected to progress through eastern and east central Missouri as well as much of southwest Illinois tonight and be moving through the eastern Ozarks Wednesday morning. Nearly all short range guidance shows convection developing on the front late this afternoon or early this evening over southwest Iowa and northwest Missouri back into eastern Kansas. This forecast corresponds well to an area of cumulus that`s developed over Iowa and northwest Missouri. There doesn`t appear to be much vertical development at this time due to a strong capping inversion, but it looks like the cap will be wiped away by an approaching short wave trough. The strength and coverage of the convection this evening varies from model to model, but the consensus forecast is that any storms which do form this evening will weaken and/or dissipate as they move into northeast and central Missouri tonight with the cold front. This scenario is borne out in every piece of deterministic guidance, the CAMs, and the HREF. In fact, 4hr max updraft strength drops off so sharply during the late evening/overnight that I`m questioning whether we`ll see any thunderstorms in our forecast area at all. In the favor of storms, there should still be plenty of instability with 1000-1500 J/Kg of MUCAPE ahead of the front according to the GFS. The RAP shows similar values, if not a bit higher, so will keep low chance to slight chance for showers and storms in the forecast, but most evidence points to a mostly dry FROPA. With the front sagging south on Wednesday, forcing for additional storms will linger over the eastern Ozarks Wednesday afternoon, but most of the forecast area should be dry, and somewhat cooler than today. Carney .LONG TERM... (Wednesday Night through Next Tuesday) Issued at 234 PM CDT Tue Jun 21 2022 Any potential for precip should be out of the area by 00Z Thursday, with the front well south into the Lower Mississippi Valley. Somewhat a cooler and noticeably drier airmass will filter into the Mid Mississippi Valley overnight Wednesday night into Thursday, with surface dew points dipping into the low and mid 60s and highs likely topping out in the mid 80s to around 90. The respite from heat and humidity looks brief, as the upper level ridge maintains its grip on the center of the U.S. at least through Saturday. A vigorous short wave moves across the northwestern U.S. along the Canada border Friday, and into the northern Plains Saturday, forcing low level cyclogenesis as it translates east. This will bring low level southerly flow back to the Mid Mississippi Valley for Friday and Saturday ahead of the short wave. Deterministic guidance shows highs rising back into the low to mid 90s on Friday, and the mid and upper 90s on Saturday. This looks reasonable as the models show the thermal ridge at 850mb building smack over Missouri and southwest Illinois, with temperatures around 22C on Friday and 24-26C on Saturday. GEFS and NAEFS show 90-97th climatological percentile on 850mb temps on Friday and 97-99th percentile on Saturday. While ECENS is similar on Friday, it`s warmer on Saturday, approaching climatological max Saturday afternoon. I therefore still feel pretty confident in forecasting near-record high temperatures on Saturday while we`re in the teeth of the thermal ridge. The short wave moves across the Upper Midwest into the Great Lakes by Sunday afternoon. Its attendant surface cold front should move through the Mid Mississippi Valley Saturday night into early Sunday morning. While the GFS does kick out some precip, the ECMWF shows very little. The timing of the FROPA is certainly not favorable for widespread, surface-based convection, so my confidence in getting much rain with this front is fairly low. However, the upper level pattern shifts with the short wave trough amplifying over the eastern 1/3 of the CONUS and the ridge retreating back over the Rocky Mountains. This puts the Mississippi Valley into northwest flow and a large cool/dry surface high builds across the Midwest and Ohio Valley. 850mb temperatures in the ensembles drop to near the 10th climatological percentile 12-14C by Monday, and stay in the 14- 16C range for Tuesday. NBM temperatures for Sunday through next Tuesday continue to be the warmest, or nearly the warmest of the guidance suite; however WPC cluster analysis shows a monopole signal in EOF1 associated with the trough, indicating some variance in amplitude. This lends more uncertainty to the temperature forecast out that far, so will stick with the NBM for now. Carney && .AVIATION... (For the 06z TAFs through 06z Wednesday Night) Issued at 1031 PM CDT Tue Jun 21 2022 Showers and thunderstorms have formed along the cold front stretched across western Missouri into central Illinois. Showers and thunderstorms will continue along the front as it drops southeast through the region, though coverage is expected to diminish as it does. MVFR flight conditions are expected briefly if a shower or thunderstorm moves across the terminal space. This is most likely to occur at KUIN during the first hours of the TAF period. Confidence is significantly lower that showers and thunderstorms will impact the mid-Missouri and St. Louis metro terminals. VFR flight conditions will prevail in the wake of the front and associated precipitation. Winds will shift from southwesterly to the northwest as the front moves through the region. MRM && .PRELIMINARY POINT TEMPS/POPS... Saint Louis 77 92 71 91 / 10 30 5 0 Quincy 71 87 66 87 / 30 10 0 5 Columbia 72 89 68 88 / 30 30 5 5 Jefferson City 73 90 68 89 / 20 30 5 5 Salem 74 94 68 90 / 5 30 0 0 Farmington 72 92 66 89 / 5 30 5 5 && .LSX WATCHES/WARNINGS/ADVISORIES... MO...None. IL...None. && $$ WFO LSX
Area Forecast Discussion
National Weather Service Paducah KY
625 PM CDT Tue Jun 21 2022 .UPDATE... Issued at 621 PM CDT Tue Jun 21 2022 Updated aviation discussion for 00z TAFs. && .SHORT TERM...(Tonight through Thursday night) Issued at 300 PM CDT Tue Jun 21 2022 The main concerns in the short term portion of the forecast will be return of triple digit heat index values and the potential of isolated to scattered thunderstorms Wednesday afternoon. The latest RAP analysis shows a 595 dm ridge centered over the Mid- South. Temperatures have responded accordingly, with values in the middle to upper 90s at most locations. Dew point values have also crept back into the lower to middle 60s. Tonight will be warm with clear skies as we remain under the influence of surface high pressure over the southeast CONUS. Low temperatures will generally fall into the lower 70s. On Wednesday, a weak surface boundary will begin to move from NW to SE across the forecast area. Dew points will pool ahead of this boundary, increasing into the lower 70s Wednesday afternoon. It will be another very hot day, with high temperatures again in the middle to upper 90s. This will result in widespread heat index values of 100 to 105 degrees during the heat of the day. Since 105 is the threshold for a Heat Advisory, decided to issue a Special Weather Statement highlighting the heat risk and let the midnight shift decide on the need for a formal heat headline. Isolated to scattered thunderstorm development is expected (PoPs of 15-30%) from late morning through the afternoon ahead of the cold front. The environment will be typical for summertime pulse convection in our region, with plentiful instability (MLCAPE values around 2000 J/kg) but very little shear. Forecast model soundings show quite a bit of mid- level dry air, so the potential for a few severe- level downbursts is there in the afternoon. SPC has a marginal risk for the northeast part of the forecast area, and that looks OK for now. Behind the frontal passage on Thursday, (slightly) cooler and less humidity conditions will arrive on the heels of a northerly wind shift. High temperatures will range from the upper 80s to lower 90s. Dew point temperatures will be firmly in the comfortable range, in the upper 50s to lower 60s. .LONG TERM...(Friday through Tuesday) Issued at 300 PM CDT Tue Jun 21 2022 Mid level heights are forecast by the medium range models to begin rising again by the beginning of the extended forecast period. A minor disturbance might generate a bit of measurable rainfall north of I-64 Sat morning, but otherwise, the main story will be the heat on that day as a ridge aloft strengthens ahead of a northern stream mid level shortwave. The NBM temps provided by Forecast Builder appeared to be somewhere near the 50 percentile, and this signal has been around for a while, so it seemed reasonably reliable. Surface dewpoints in the 50s Fri are forecast to rise into the 60s by Sat, but no more, due to lack of robust moist return flow. Upper 90s temps are forecast Sat afternoon, with 100 possible in a few spots. Heat indices of mid/upper 90s are expected in the eastern half of the PAH forecast area, with 100+ expected in the western half. In fact, the westernmost parts of southeastern MO may reach 105+. This will be followed by tepid lows Sat night in the middle 70s. The models appeared to be in reasonable agreement depicting a vigorous mid level shortwave, moving rapidly eastward near the U.S./Canadian border during the weekend. This will be the impetus for a surface cold front sweeping through our region on Sun. This feature will be rather moisture-starved with deeper moisture to our south and east, so QPF will be also limited for us. Isolated to scattered showers/tstms will probably pop up mainly during the daylight hours. At this time, wind shear appeared limited in the models, in addition to lapse rates. All pcpn should be out of eastern parts of the region by the wee hours of Sun night. The new airmass will provide northerly to northeasterly winds and a moderation of temps. Starting Sun night, lows will be back in the 60s across the region, with highs in the 80s. && .AVIATION... Issued at 621 PM CDT Tue Jun 21 2022 Clear skies and calm winds expected tonight. Winds switch around to northwesterly 5-10 kts tomorrow behind a cold frontal passage early. There likely will be some isolated to scattered showers and storms around after 18z tomorrow, but confidence is low in any one terminal being impacted at this time. Brief vsby reductions and gusty winds would be possible with the heavier activity. && .PAH WATCHES/WARNINGS/ADVISORIES... IL...None. MO...None. IN...None. KY...None. && $$ UPDATE...SP SHORT TERM...DWS LONG TERM...DB AVIATION...SP
Area Forecast Discussion
National Weather Service Blacksburg VA
913 PM EDT Tue Jun 21 2022 .SYNOPSIS... High pressure increases from the west through tonight. Meanwhile a frontal system will slide southward toward the mid-Atlantic Wednesday, passing through by later Thursday. Ahead of the front expect increasing heat and humidity and a chance for showers and thunderstorms as the front crosses the Mid Atlantic region on Wednesday night and Thursday. High pressure and a lower probability of showers and thunderstorms are expected for Friday and Saturday. && .NEAR TERM /THROUGH WEDNESDAY NIGHT/... As of 913 PM EDT Tuesday... Made some minor adjustments to temperatures and dew points for tonight. Modified weather and pops a little for Wednesday during late afternoon. More changes to forecast after 00z models come in. Previous discussion: As of 635 PM EDT Tuesday... Dry tonight, then chance of showers and storms late Wednesday. Made some minor adjustments in temperatures for this evening into tonight utilizing the latest surface obs, their trends and blended in the NBM. Low temperatures overnight will range from the mid 50s in the mountains to the lower 60s in the piedmont. The upper low/trough off the Northeast coast starting to head west toward the mid-Atlantic coast by Wednesday afternoon. A disturbance rides atop the ridge from the Great Lakes region into the Appalachians Wednesday afternoon into Wednesday night. HiRes Models like NAMnest and HRRR show convection dropping south across the region after 20z. SPC highlighted the potential for strong to severe storms with the marginal risk in Day 2 Convective Outlook. Healthy MLCAPEs with weak shear expected with the thunderstorms. The main threats would be winds and hail with the stronger updrafts. High confidence in Near Term Forecast. Previous discussion: As of 115 PM EDT Tuesday... Going drier through most of the period with increasing heat... Despite the heat increasing due to the upper ridge over the lower MS Valley into the southern Appalachians, the surface flow has been more out of the north and as such, dewpoints have been held in check. Area should remain dry through most of Wednesday, with upper low/trough off the northeast coast starting to head west toward the mid-Atlantic coast by Wednesday afternoon. Some model differences in potential disturbance riding atop the ridge from the Great Lakes into the central Appalachians Wed afternoon, with most showing main lift and forcing east/northeast over the mid-Atlantic/Delmarva area. Will allow for low chance pops to reach the I-64 corridor Wed afternoon, with maybe an isolated storm as far south as the U.S. 460 corridor. Will see if any convective blowoff occurs if more organized activity develops upstream. For now will lean toward previous and MAV with mid 90s east, to mid 80s/near 90 west of the Blue Ridge. Forecast confidence is high for all elements through midday Wednesday then shift to average for temps/sky/pops Wed afternoon. && .SHORT TERM /THURSDAY THROUGH FRIDAY/... As of 230 PM EDT Tuesday... Showers and storms through Thursday, quiet Friday... A trough through the Great Lakes and eastern Canada will drop a frontal boundary to the south. This front crosses our area late Wednesday, and begins to stall as it becomes distanced from the forcing of the trough. While the front lingers near the Carolinas through Thursday, it will serve as an initiator of storms Wednesday night through Thursday afternoon. By late Thursday, a closed upper low off the Mid-Atlantic coast will pick up the boundary and become part of the northern stream, thus pulling the stalled front out of the area by Thursday night. With a large broad ridge centered over the southern plains and no dynamics in play near our CWA, Friday will be a return to quiet, summery conditions. Daily highs will be in the 80s and 90s throughout this forecast period, but an influx of moisture will raise dewpoints 5-10 degrees from where they started earlier this week. So despite being a few degrees cooler on Thursday and Friday than it will have been Wednesday, the increased humidity will make it feel just as hot, if not a bit warmer. && .LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/... As of 230 PM EDT Tuesday... Hot and humid before a front brings showers early next week... Saturday will also see our area underneath a surface high, but given the increased moisture and temperatures, we maintain slight chance to chance PoPs for diurnal storms Saturday afternoon and evening. That high will be pushed out of the area beginning Sunday as an upper trough barrels across the northern plains and enters the Great Lakes region by Monday. A front will come along with it, dangling to the south and crossing our area early next week on Monday or Tuesday, timing is not quite settled yet with this system. The trough is well agreed upon by most guidance, so confidence in an early week system bringing showers and storms is high. The weekend will be summery with temperatures above normal, and then a little cooling behind the early week system. && .AVIATION /01Z WEDNESDAY THROUGH SUNDAY/... As of 635 PM EDT Tuesday... VFR conditions will prevail tonight through Wednesday morning. A few mid/high clouds with winds staying mainly west-northwest and under 10kts. An disturbance will ride atop the ridge from the Great Lakes into the central Appalachians Wednesday afternoon. The best lift and forcing remains east and northeast over the mid-Atlantic/Delmarva area. Isolated to scattered MVFR showers and thunderstorms look to move in from the north later Wednesday afternoon, with best chance not til after 00z. Above average confidence for ceiling, visibility and wind. Extended Aviation Discussion... A cold front crosses the region Thursday, so despite the storms most areas should stay VFR, with sub-VFR in any tstms. Mainly VFR conditions through Saturday, with isolated storms possible Saturday. Could also have late night fog brought on by rain and increased RH. Sunday looks unsettled with scattered MVFR showers and thunderstorms, mainly during the afternoon and evening hours. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...None. NC...None. WV...None. && $$ SYNOPSIS...WP NEAR TERM...KK/WP SHORT TERM...VFJ LONG TERM...VFJ AVIATION...KK/WP
Area Forecast Discussion
National Weather Service San Diego CA
225 PM PDT Tue Jun 21 2022 .SYNOPSIS... An upper low off Point Conception will draw monsoonal moisture northward into southern California tonight through Wednesday, leading to the development of scattered showers and isolated thunderstorms which will be most prevalent over the mountains and deserts on Wednesday. Thunderstorms could produce strong gusty winds and brief heavy rainfall. Drier southwest flow aloft will develop on Thursday with a slight chance of thunderstorms in the afternoon, mainly over the mountains. Then drier with warming conditions Friday through Saturday. Monsoonal moisture could move back in early next week. && .DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE... SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO COUNTIES... -Forecast Highlights- * First monsoonal moisture surge of the season is here * Result will be scattered showers and isolated thunderstorms * Low risk of flash flooding mountains and deserts on Wednesday The first monsoonal moisture surge of the season has arrived! Looking out the window we are seeing beautiful altocumulus clouds increasing from the south. This could lead to an amazing sunset this evening. These clouds are indicative of mid level moisture moving northward from Mexico on south-southeasterly mid level steering winds. SPC mesoanalysis shows Precipitable Water (PW) at less than 0.50 inches over Orange County with 0.80 inches near the international border. PW near 1.5 inches resides over the northern Gulf of California. A southeast moisture surge will send higher PW of 1.0-1.4" into SoCal (highest near the border) with surface dewpoints even soaring into the lower-mid 60s into at least southern parts of the Coachella Valley by Wednesday morning. It will be a bit more humid elsewhere as well associated with this monsoonal push. The moisture advection is taking place to the east of an upper low off Point Conception. HRRR shows scattered showers developing reaching into Southern San Diego County after midnight with movement from south to north across the region through Wednesday morning. Point forecast soundings show little instability with CAPE off global and hi-res models less than 100 J/KG, but often elevated convection can be underestimated, so we have kept a slight chance of thunderstorms in the forecast after midnight through Wednesday morning. There is a stronger signal for elevated tstorms to the north of our service area late tonight- Wednesday morning. Rainfall amounts overnight-Wednesday morning will mostly be trace-0.10 inches in the shower activity, perhaps up to 0.25 inches at higher elevations (less evaporation - closer to the moisture). By Wednesday afternoon, monsoonal moisture will be fully in place and with surface mass convergence expected to occur over the mountains, this looks to provide the best opportunity of thunderstorms to develop with southwest steering flow oriented towards the deserts. The highest thunderstorms chances will be from the San Diego County mountains extending north to the Santa Rosas where localized amounts of 0.50-1.00 inches will be possible. Most cells will produce 0.25-0.50 inches. Overall lesser rainfall amounts will impact the San Bernardino County mountains. There is a low risk of flash flooding over the mountains and deserts Wednesday afternoon into early evening. Strong downburst winds are a possibility in the thunderstorms as well. This risk is highest with any thunderstorms that move out over the deserts in an environment favorable for microbursts (inverted V sounding/very dry air sub-cloud level). The aforementioned low near Point Conception will move east across central California on Thursday with westerly steering winds sending the monsoonal moisture off to the east. There may be just enough moisture remaining Thursday afternoon to allow for isolated showers or thunderstorms to develop over the mountains on Thursday before dry weather returns Friday and into the upcoming weekend while temperatures warm by a few degrees. Another slight increase in monsoonal moisture may enter the picture again early next week to allow for a returning risk of showers/tstorms for the mountains and deserts. Temperatures overall will run above average through the period with the hottest conditions expected this upcoming weekend. && .AVIATION... 212100Z....Mostly clear skies with unrestricted vis expected through early this evening. Increasing mid-level clouds will occur with bases AOA 10,000 FT MSL. Low to moderate chance of low clouds 800-1000 ft MSL impacting coastal areas after 07Z tonight. This would be accompanied by vis restrictions 1-3SM if these clouds do impact the coast. && .MARINE... No hazardous marine weather is expected today. There is a slight chance of showers and thunderstorms across the coastal waters late tonight into Wednesday, with isolated cloud-to-water lightning being the primary concern. Breezy northwest winds will occur each afternoon and evening late this week into this weekend. && .FIRE WEATHER... An upper low off of Point Conception will draw monsoonal moisture northward into southern California tonight through Wednesday, leading to the development of scattered showers and isolated thunderstorms which will be most prevalent over the mountains and deserts on Wednesday. Thunderstorms could produce strong gusty winds and brief heavy rainfall. Scattered showers are forecast to spread northwestward across the area late tonight into Wednesday morning. A thunderstorm cannot be ruled out. The threat of dry lighting is low. Thunderstorms are most likely to occur over the mountains Wednesday afternoon but they are expected to contain wetting rainfall. In fact, a few heavy cells are possible. Drying is expected to begin on Thursday, but there could still be enough residual moisture for isolated thunderstorms near the mountains Thursday afternoon. && .SKYWARN... Skywarn activation is not requested. However weather spotters are encouraged to report significant weather conditions. && .SGX WATCHES/WARNINGS/ADVISORIES... CA...NONE. PZ...NONE. && $$ PUBLIC...Gregoria AVIATION/MARINE...APR