Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 07/08/24


Area Forecast Discussion...UPDATED
National Weather Service Albuquerque NM
729 PM MDT Sun Jul 7 2024 ...New UPDATE... .UPDATE... Issued at 705 PM MDT Sun Jul 7 2024 Updated forecast to remove freezing rain and freezing drizzle mention from the afternoon forecast package as well as to include the 00Z aviation discussion. Forecast Builder erroneously inserted two freezing PoT grids as it sometimes likes to do. Remainder of forecast remains on track with no further updates planned. && .SYNOPSIS... Issued at 340 PM MDT Sun Jul 7 2024 A moist backdoor cold front will trigger strong to severe thunderstorms over northeast and east central areas tonight. The front will push through gaps in the central mountain chain with a gusty east wind below canyons opening into the central valley commencing around midnight tonight, then continuing through Monday. The strongest gusts may reach up to 55 mph below Tijeras Canyon in Albuquerque. Much cooler temperatures area forecast across northern, central, and eastern areas Monday. Greater thunderstorm coverage is forecast mainly east of the continental divide Monday through Wednesday, then from the east slopes of the central mountain chain westward Thursday through Saturday. && .SHORT TERM... (This evening through Monday night) Issued at 340 PM MDT Sun Jul 7 2024 High pressure aloft remains over CA while an upper level trough continues to carve out over the northern Great Plains this afternoon. This has kept northwesterly flow aloft over NM with very dry air having invaded a large majority of the forecast area as seen by plummeting dewpoints in the teens, 20s and 30s and falling PWATs. The exception is in northeastern and east central NM where a moist backdoor front associated with the northern Great Plains trough has infiltrated. The front is bumping up against the Sangre de Cristos and convective initiation is getting underway amid the moist upslope flow. Lots of directional wind shear is in place with 1000-1500 J/Kg of MLCAPE per the latest RAP analysis, so strong to perhaps severe cells will likely carry on into at least the evening, if not the early morning hours. The CAMs keep activity focused over the northeastern quadrant of the state, not really overtaking much of the TX/OK panhandle until after midnight. Given recent high resolution and CAMs often delayed representation of CI, this could be too late of a display of storms with cells potentially expanding farther south of I-40 by the midnight to early morning hours, so POPs were expanded a bit into east central zones. Synoptic high pressure would already be building over eastern NM and west TX, and how the convection fares could potentially intensify this if widespread convection breaks out over west TX a few hours earlier (evening) than modeled. This would hasten and strengthen the gap/canyon wind, but models and MOS guidance are not on board with this scenario. This makes it tricky with the High Wind Watch for the ABQ metro, but for now have opted to just convert it to a Wind Advisory. As we get closer to dawn and into the late morning eastern zones should begin to stabilize more, transitioning any precip from a convective mode to more of a stratiform one. This could yield some light rain or even drizzle in some east central to southeastern zones into late Monday morning with the stable conditions limiting, but likely not fully eliminating thunder opportunities even into the afternoon. This will put the focus for convective initiation over the northern mountains early Monday afternoon, and while CAMs are not overly enthused, the Continental Divide could be another initiation point as moist easterly upslope flow would be favorable on the east faces. With the northern plains trough moving farther east and the upper high setting up over southern CA, the flow aloft would remain out of the north northeast with lots of directional shear to make opportunities for severe storms. && .LONG TERM... (Tuesday through Saturday) Issued at 340 PM MDT Sun Jul 7 2024 A moist southeasterly return flow at the surface will enable scattered to numerous showers and thunderstorms to develop both Tuesday and Wednesday afternoons with the greatest coverage of cells along the central mountain chain and over the southwest mountains. With a mid-level high pressure system centered over the Great Basin, storms will generally move from north to south over the forecast area both days. Perturbations in the northerly flow aloft will ride over an axis of higher instability and favorable bulk shear for at least a few strong-to-severe thunderstorms east of the central mountain chain both days. Temperatures will trend warmer both days while remaining a few to several degrees below 1991-2020 averages across the east. Surface winds are currently projected to veer more out of the south on Thursday and Friday causing moisture to trend lower over eastern areas and higher over western areas each day. This will result in a downtick in thunderstorm coverage from the central mountain chain eastward, and shift the focus for convection more over western areas. High temperatures will mostly continue warming in the east as well, with readings roughly around 30-year averages areawide by Friday. The upper high is forecast to migrate westward over UT, shifting the storm motion from northwest to southeast Thursday and moreso Friday. The upper high is forecast to recenter over CO by Saturday causing NM storms to move a bit more toward the west. However, there will could be a downtick in storm coverage and rainfall intensity on Saturday as drier air and an area of subsidence move over southeast and central parts of the forecast area ahead of an easterly wave tracking northwestward over northern Mexico. && .AVIATION... (00Z TAFS) Issued at 646 PM MDT Sun Jul 7 2024 Widespread MVFR to IFR ceilings will return to much of the eastern half of the state overnight thanks to moist easterly upslope flow behind a backdoor front. Isolated showers and thunderstorms will continue to fire along the east slopes of the Sangre de Cristo mountains tonight, moving southeastward over the northeast highlands and northeast plains. This same front will push west through the canyons of the central mountain chain late this evening, making it to near the AZ border by morning. Gusty east canyon winds of 35 to 45 kt will be possible in the ABQ metro downwind of Tijeras Canyon including KABQ between 08/0600Z and 08/1600Z. Strong east and southeast winds continue through Monday, gradually diminishing during the afternoon. Scattered showers and thunderstorms are forecast to favor the central mountain chain eastward Monday afternoon with isolated activity between the Rio Grande Valley and the Continental Divide. && .FIRE WEATHER... Issued at 340 PM MDT Sun Jul 7 2024 Critical fire weather conditions are starting to get underway over northwestern NM this afternoon as unseasonably strong west northwest winds continue to draw hotter and drier air into the state. Much of the remaining areas of western and central NM are also seeing dry and hot conditions, but the winds are not quite as strong. In northeastern and east central NM, a moist backdoor cold front is currently invading from the northeast, bringing gusty and shifting winds, but the arrival of higher humidity is eliminating concerns for critical fire weather behind it. Storms will continue building and developing over northeastern and some east central portions of NM this evening and perhaps even after midnight. While this is occurring the front will accelerate westward into the Rio Grande valley and toward the Continental Divide. This could produce strong canyon winds with gusts of 35 to 55 mph immediately downwind of vulnerable gaps and canyons tonight. The front will increase moisture and lead to a more active shower and thunderstorm pattern into Monday and the rest of the week (outside of the far northwestern and west central zones). This wetter and generally more tranquil pattern (from a wind standpoint) will keep fire weather concerns at bay while offering scattered footprints of soaking rainfall. && .PRELIMINARY POINT TEMPS/POPS... Farmington...................... 57 90 59 92 / 0 0 0 0 Dulce........................... 44 85 44 87 / 0 30 20 30 Cuba............................ 52 82 50 85 / 0 30 20 20 Gallup.......................... 49 89 51 90 / 0 0 0 10 El Morro........................ 54 83 53 84 / 0 10 20 30 Grants.......................... 52 85 51 87 / 0 10 20 30 Quemado......................... 54 87 55 88 / 0 10 20 50 Magdalena....................... 59 82 56 84 / 0 20 20 50 Datil........................... 56 83 54 84 / 0 20 20 50 Reserve......................... 54 94 52 92 / 5 10 10 60 Glenwood........................ 67 101 65 96 / 10 10 10 70 Chama........................... 44 77 44 79 / 5 60 40 50 Los Alamos...................... 57 76 54 79 / 10 70 30 60 Pecos........................... 54 72 51 81 / 30 70 30 70 Cerro/Questa.................... 39 75 38 78 / 30 80 30 70 Red River....................... 42 64 39 70 / 30 80 30 80 Angel Fire...................... 41 67 37 72 / 40 80 30 70 Taos............................ 49 78 46 82 / 20 70 30 50 Mora............................ 49 68 46 76 / 40 80 30 70 Espanola........................ 55 84 54 87 / 10 60 30 30 Santa Fe........................ 57 76 53 82 / 20 70 40 60 Santa Fe Airport................ 57 79 53 84 / 10 50 30 40 Albuquerque Foothills........... 62 83 59 89 / 5 40 30 40 Albuquerque Heights............. 63 85 60 91 / 0 20 20 20 Albuquerque Valley.............. 63 87 59 93 / 0 10 10 20 Albuquerque West Mesa........... 64 85 60 92 / 0 20 10 20 Belen........................... 61 87 57 92 / 0 10 20 30 Bernalillo...................... 64 86 59 92 / 5 30 20 20 Bosque Farms.................... 61 86 57 92 / 0 10 20 20 Corrales........................ 63 87 59 92 / 0 20 20 20 Los Lunas....................... 62 87 58 92 / 0 10 10 20 Placitas........................ 61 81 57 87 / 5 30 20 40 Rio Rancho...................... 64 86 59 92 / 0 20 20 20 Socorro......................... 65 90 61 94 / 0 10 20 40 Sandia Park/Cedar Crest......... 56 75 53 83 / 5 40 30 40 Tijeras......................... 58 77 54 85 / 5 30 30 40 Edgewood........................ 55 76 52 86 / 5 40 40 40 Moriarty/Estancia............... 54 75 49 86 / 10 40 40 40 Clines Corners.................. 52 69 49 80 / 20 50 30 50 Mountainair..................... 55 75 51 84 / 5 30 30 50 Gran Quivira.................... 55 76 52 84 / 5 40 30 50 Carrizozo....................... 62 83 58 87 / 0 40 30 60 Ruidoso......................... 55 73 52 77 / 0 60 40 70 Capulin......................... 50 67 47 76 / 70 60 10 40 Raton........................... 52 72 49 80 / 70 60 10 40 Springer........................ 56 73 52 81 / 60 60 20 50 Las Vegas....................... 53 67 49 76 / 60 70 30 60 Clayton......................... 57 74 54 82 / 60 30 10 10 Roy............................. 57 70 52 79 / 70 40 20 40 Conchas......................... 61 75 57 87 / 70 40 20 20 Santa Rosa...................... 60 72 55 82 / 40 40 20 30 Tucumcari....................... 60 76 55 86 / 70 50 20 5 Clovis.......................... 62 77 58 87 / 30 70 30 10 Portales........................ 62 78 58 87 / 20 70 40 10 Fort Sumner..................... 63 77 58 87 / 20 50 30 10 Roswell......................... 70 83 65 92 / 5 60 50 20 Picacho......................... 62 77 59 84 / 5 60 40 50 Elk............................. 57 78 55 83 / 0 60 40 60 && .ABQ WATCHES/WARNINGS/ADVISORIES... Wind Advisory from 11 PM this evening to 9 AM MDT Monday for NMZ219. Heat Advisory until 9 PM MDT this evening for NMZ238. && $$ SHORT TERM...52 LONG TERM....44 AVIATION...52
Area Forecast Discussion...UPDATED
National Weather Service Aberdeen SD
921 PM CDT Sun Jul 7 2024 .KEY MESSAGES... - Isolated shower and thunderstorm chances (15-25%) remain in the forecast on both Monday and Tuesday, mainly during the afternoon and evening hours across northeastern SD into west central MN. - Heat and humidity will be on the increase through the week into the weekend. By Friday/Saturday temperatures will be about 5 to 10 degrees above average, with highs in the upper 80s to mid 90s and lows in the upper 60s to near 70 with dewpoints well into the 60s to near 70 degrees. && .UPDATE... Issued at 919 PM CDT Sun Jul 7 2024 Still some shower and thunderstorm activity occurring across parts of central South Dakota, but expect this to diminish and go away by 04Z or so. No changes made to winds or temperatures at this time. && .SHORT TERM /THIS EVENING THROUGH MONDAY NIGHT/... Issued at 208 PM CDT Sun Jul 7 2024 The longwave trough remains over the central and northern CONUS with the axis from northern MN and southwestward through the Southern Plains through 00Z. As of 1PM, satellite imagery indicates a vort max/mid low spinning over northern MN along with a vort max/shortwave over north central SD. This shortwave and energy behind the low/vort max in MN will aid in lift for convection. Still pretty moist out as PWAT values are around an inch which is around average for this time of year, according to NAEFS. Surface dewpoints are currently in the upper 50s to the lower 60s this afternoon with 700mb temps around 2-3 degrees. Daytime heating continues to steepen low level lapse rates with MU/MLCape values reaching to around 1000- 1300 j/kg or so with values up to around 1500 j/kg over far northeastern to eastern SD into west central MN per HREF. Rap values seem to be running a little higher. Several soundings indicate more skinny CAPE profiles with mid level lapse rates marginal around 6- 6.5C/km-1 and minimal shear. It is interesting to note that NST parameter at 18Z ranges from 0.5 across the CWA to values of 2-3 over northeastern SD into southeastern ND. So cold air funnels/landspouts could be possible as we have surface vorticity/0- 3km ML Cape values of 100-170j/kg (highest over northeastern SD) on top of each other, per SPC meso page. HREF/CAMS indicates convection chances over much of the CWA through this evening with pops ranging from 30-40%. Storm mode will be more pulse "hit and miss" summer type thunderstorms, with storm motion cyclonically around vort max and behind the low which is why the grids are more widespread in coverage. Severe threat remains low as 2-5UH>75m2s2 does not show anything exciting compared to yesterday. With the cooler air aloft and thermodynamics mentioned above, some of these storms could produce small hail (if strong enough) with the main threat being lightning. Pops will diminish with sunset. For Monday, the longwave trough pushes just a bit east with a high pressure system centered over the Rockies in the morning and over the central and northern Plains by the evening. Once again daytime heating and Cape up to 1000 J/kg (which is mainly limited over the far eastern CWA, closer to northern axis of trough) along with dp`s in the lower 60s, could bring some isolated storms in the afternoon and evening. With this limited instability and skinny cape profiles, pops chances are a bit lower ranging around 15% (manually added). Lows tonight will be in the mid to upper 50s/60 and highs for Monday ranging from the upper 70s to the mid 80s. && .LONG TERM /TUESDAY THROUGH SUNDAY/... Issued at 208 PM CDT Sun Jul 7 2024 With minimal differences among ensemble clusters, confidence in the large scale pattern for the long term is relatively high and this carries over to the other mass fields such as the temperature and wind forecast. There is greater uncertainty in the precipitation potential however. The northern plains will initially be in an upper level northwest flow pattern as a SW CONUS high builds. The surface pressure pattern remains weak but models suggest low level moisture, with 60+ dewpoints (especially across our eastern CWA) will be fairly persistent. This does introduce some uncertainty into the blended model depiction of a mostly dry forecast through mid week. Instead, we could be on the repeat cycle of afternoon pulse convection. Either way, coverage and POPs would be quite low. Continued the previous trend of including at least a low POP on Tuesday, however this may need to be considered Wednesday and Thursday as well. It will be late in the week before the ridge of high pressure traverses eastward and above normal air spreads across the plains states. Definitely not a high amplitude ridge however, and models suggest a parade of ridge riders traversing the pattern. LREF probabilities of 700 mb temps exceeding 14C are highest on Saturday and Sunday, generally ranging from 70-80% from our southwest CWA to 30-50% across our northeast CWA. This suggests a fairly healthy CAP for the weekend. Likewise, probabilities of surface temps exceeding 90 degrees is greatest for our western CWA, however current ensemble progs suggest a 50% chance or less of realizing heat advisory temps. && .AVIATION /00Z TAFS THROUGH 00Z MONDAY/... Issued at 623 PM CDT Sun Jul 7 2024 Terminals KABR,KATY,KPIR,KMBG Scattered showers and thunderstorms will continue across the area this evening. Once the sun goes down, the precipitation will come to an end with the loss of daytime heating. Periods of MVFR vsbys are possible with the thunderstorms. Otherwise, VFR conditions will prevail across the area tonight and through the day Monday. && .ABR WATCHES/WARNINGS/ADVISORIES... SD...None. MN...None. && $$ UPDATE...Parkin SHORT TERM...MMM LONG TERM...Serr AVIATION...Parkin
Area Forecast Discussion
National Weather Service La Crosse WI
1031 PM CDT Sun Jul 7 2024 .KEY MESSAGES... - Isolated to scattered showers/storms are possible over the next few days, with rain chances gradually lessening for mid/late week. Most hours will be dry, though, and the risk for organized heavy rain/severe weather is low. - Near to below average temperatures early this week will trend upward by next weekend. - Minor to moderate flooding continues along the Mississippi River, but river levels will be falling gradually over the coming week. && .DISCUSSION... Issued at 155 PM CDT Sun Jul 7 2024 This Evening - Wednesday: GOES water vapor channel and RAP 500 mb heights show a broad trough extending from the northern Rockies into the western Great Lakes early this afternoon, with several embedded vorticity maxima noted across the Dakotas into Minnesota. Surface analysis early this afternoon showed a diffuse boundary across western IA/MN. SPC mesoanalysis indicated pockets of 1000 J/kg MLCAPE along with 20-25 kts of effective shear as of 2 pm. Within minimal inhibition, isolated to scattered showers/storms are possible this afternoon into tonight, although lift to help generate organized storms this afternoon is nebulous. There is a slightly stronger synoptic lift signal overnight from northeast Iowa into central Wisconsin ahead of the trough axis. Any storms should be subsevere, although gusty winds/small hail cannot be ruled out. Although rain amounts overall will be light spatially, localized amounts of 1 to 2" could occur with slow moving storms. With light boundary layer flow, patchy fog could develop early Monday, but confidence is low given uncertainty in cloud/precip coverage. Additional isolated to scattered storms are possible Monday afternoon with diurnal destabilization beneath the mid-level cold pool/trough. Low, mainly diurnal shower/storm chances continue into mid-week within the broadly cyclonic flow. However, severe storm potential should be low as both shear/instability are fairly marginal. Will have to monitor the remnants of Beryl, as guidance lifts this system northeastward by mid-week towards the Great Lakes trough. Current multi-model global ensemble forecasts suggest the bulk of the rainfall will skirt south across the Mid-Mississippi Valley into the Great Lakes/Ohio Valley with less than a 10% chance for at least 1/2 an inch of rain across far southwest Wisconsin on Wednesday. Temps through mid-week will generally be near to below average. Thursday - Sunday: Mid-level heights will begin to build late this week into the coming weekend as the broad troughing across the Upper MS Valley loses its influence. As this occurs, there is little signal for meaningful rainfall late this coming work week. By next weekend, increasing quasi-zonal to northwest mid-level flow may develop across the Upper Midwest along the periphery of the strong ridge centered over the Rockies. Any embedded shortwaves interacting with the moist, unstable environment could result in showers/storms, but predictability in these details is very low at this time. Otherwise, the pattern favors rebounding temps back above average heading into the weekend, although spread in the model suite also increases, especially heading northward, likely due to uncertainty in the amplitude/orientation of the flow and timing of shortwave troughs/convection. However, some locations could be back up near 90 by later in the week or next weekend. NBM probabilities for 90F temps increase to 20 to 60% across parts of northeast Iowa, southwest into central Wisconsin and the immediate Mississippi River Valley by next Sunday. && .AVIATION /06Z TAFS THROUGH 06Z TUESDAY/... Issued at 1023 PM CDT Sun Jul 7 2024 Showers and storms continue into the overnight hours primarily from southeast Minnesota through central Wisconsin. Main impact has been ponding water on roadways and scattered thunder. Primary aviation concern remains to be the potential for valley fog. Highest confidence will be in the more prone areas of Wisconsin River Valley and tributaries. Low to moderate confidence in Mississippi River Valley and TAF site at KLSE. Low level winds may remain strong enough to abate or limit temporal and spatial extent. Have leaned pessimistic with IFR visibilities given recent rains and overnight lingering humidity with draped frontal boundary. && .HYDROLOGY... Issued at 347 AM CDT Sun Jul 7 2024 The Mississippi River is noting falling river levels from north of Brownsville, MN with Lake City, MN falling below flood stage. Locations near crest from Brownsville, MN on south to Guttenberg, IA. River stages are expected to fall into this week from northeast Iowa and southwestern Wisconsin on northward along the Mississippi River. Generally lighter rainfall amounts of up to around 0.5" from now through Tuesday are expected, with locally higher amounts possible with any storms that pass over. May have to watch the remnants of Tropical Storm Beryl for more substantial rainfall across southwestern WI/northeast IA for Tuesday night and Wednesday. However, the probabilities for heavier rainfall with this system remain low as guidance keeps much of the heavier rainfall farther south and east of the local area. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...None. MN...None. IA...None. && $$ DISCUSSION...JM AVIATION...JAR HYDROLOGY...Naylor
Area Forecast Discussion
National Weather Service Green Bay WI
1037 PM CDT Sun Jul 7 2024 Updated aviation portion for 06Z TAF issuance .KEY MESSAGES... - Slow moving thunderstorms with heavy rain are possible tonight. - On and off chances for showers and thunderstorms will continue Monday through Wednesday. Although the severe weather threat remains low, locally heavy rainfall will be possible. - Some rivers, creeks, and streams across east-central Wisconsin will continue to run above bankfull due to recent rainfall. - A warmer and drier summer pattern may be in store toward the end of next week and into next weekend. && .DISCUSSION... Issued at 232 PM CDT Sun Jul 7 2024 Short Term...Tonight and Monday The latest RAP analysis and satellite/radar imagery show several shortwaves spinning over the northern Plains and northern Mississippi Valley. Northeast Wisconsin is positioned on the eastern periphery of these systems with moisture advection occurring in the low levels, and difficult to resolve impulses embedded with southwest flow aloft. These impulses have supplemented the 1000-2000 j/kg of surface based instability analyzed across the region to generate scattered showers and storms. Coverage has been highest over northwest Wisconsin, but think coverage will continue to increase over north-central and northeast Wisconsin as we approach peak heating late this afternoon. A strong to near severe storm is possible given the deep layer shear of 25-30 kts. Focus of this forecast is storm trends and heavy precip potential. Storm trends: After a period of storms over north-central WI this afternoon, convective allowing models indicate that a broken line of storms will move into north-central Wisconsin around mid to late evening along a weak cold front advancing eastward. These storms should be weakening as diurnal instability is lost. There may be sufficient instability leftover for a strong storm to occur, but severe weather is not expected. A second area of showers and embedded storms remains expected to move into central and east-central Wisconsin after around 3 am associated with a shortwave out of the central plains and augmented by a modest 25 kt low level jet. While there is up to 1000 j/kg of elevated instability, severe thunderstorms are not expected as effective shears are only around 20 kts. Probabilities remain low (10-30%) for rainfall amounts of 1/2" or greater, but slow storm motion around 10 kts and precipitable water values around 1.6 inches indicate some potential for heavy rainfall if convection is more widespread/potent than what it indicated in models. Shortwave troughing will be overhead for the rest of Monday. While precip early in the day will likely exit in the morning, instability of 1000-2000 j/kg will lead to redevelopment of showers and storms in the afternoon. Higher chances appear northwest of the Fox Valley where the heating curve will be less impacted by morning precip. Fog potential: Besides precipitation, guidance is also showing potential for dense fog over north-central Wisconsin late tonight. This makes sense with the precip that has occurred today. Will add to the HWO. Long Term...Monday Night Through Sunday Moisture, instability, and a weak shortwave will keep the chance for pulse showers and thunderstorms in the forecast through Tuesday. The lack of better dynamics and lift should keep coverage fairly low across the region during this period, with the best chances during the afternoon with peak heating. The next feature of interest is where Beryl ends up during the middle part of the week. NWP models seem to agree that our area will largely miss out on this feature; however, the region will still see rain as a mid level shortwave and associated positively tilted trough dive southeast from Canada through the western Great Lakes region. Instability showers and/or thunderstorms will be possible Thursday afternoon; however, with a lack of any significant dynamics or forcing coverage is expected to be isolated at best. Some weak ridging is expected to keep Friday dry, with isolated to scattered showers and thunderstorms possible next weekend as some shortwave ridge riders track through the western Great Lakes on the periphery of a larger scale ridge in place across the central CONUS. Temperatures during the week will be right around normal through Thursday. Temperatures will then warm to a few degrees normal on Friday and several degrees above normal by next weekend as the upper level ridge builds in across the central CONUS. && .AVIATION...for 06Z TAF Issuance Issued at 1036 PM CDT Sun Jul 7 2024 An upper level trough will produce scattered showers and thunderstorms as it moves slowly across Wisconsin tonight and Monday. The activity will be most abundant during the daytime and evening hours and decrease overnight. There may also be some patchy ground fog late tonight where significant rain falls. Outside of any convective activity and ground fog, VFR conditions are expected. && .GRB WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION.....MPC/Kurimski AVIATION.......RDM
Area Forecast Discussion
National Weather Service Marquette MI
737 PM EDT Sun Jul 7 2024 .KEY MESSAGES... -Scattered showers and thunderstorms over mainly the west half of Upper MI this afternoon/early evening. -Through at least Tuesday, daily chances of showers and thunderstorms, highest chances in the afternoons. -Drier weather expected for the last half of this week, though ~10% chance Beryl`s remnants complicate the forecast. -Hot weather possible into the weekend, with ~25% chance of isolated high temperatures in the 90s over the weekend. && .UPDATE... Issued at 737 PM EDT Sun Jul 7 2024 As of 730 pm EDT, cluster of showers and thunderstorms straddles the WI/MI border in eastern Gogebic County associated with a broad lower- level confluence zone. One storm briefly perked up SW of Marenisco earlier in an environment of 30 kt deep layer shear and 1000 J/kg MLCAPE, showing a broad mesocyclone and likely producing around 0.5" hail, but otherwise, activity has been fairly shallow. Still not out of the question for a stronger core to develop and result in small hail and gusty winds to the east and northeast of current activity through Baraga/Iron Counties given the aforementioned thermodynamic/kinematic environment, especially where storm mergers occur with some downstream showers moving more northerly. Storms are rather slow moving so locally heavy rainfall can be expected as well. HRRR suggests this activity may persist through around 03Z as it moves E/NE before weakening. && .SHORT TERM /THROUGH TONIGHT/... Issued at 238 PM EDT Sun Jul 7 2024 Water vapor imagery showing upper low over northern MN with several weak shortwaves rotating around it over WI and western Lake Superior. Given proximity to the U.P. combined with diurnal heating have already seen scattered shras and tsras develop over the western third of the U.P. A couple other shras have developed along the Lake Michigan lake breeze along the Seney stretch. While a brief stronger storm can`t be ruled out this afternoon given marginal shear up to 25 knots and CAPE around 1000-1250 J/kg, expect storms to lack organization. Most activity will diminish this evening with sunset but as weak shortwave migrates eastward will maintain slight/low chance pops over the eastern U.P. through the night. Areas that do see some rain over the west, especially near evening time may then see some patchy fog develop overnight tonight. Lows tonight will mainly be in the upper 50s to lower 60s. && .LONG TERM /MONDAY THROUGH SUNDAY/... Issued at 337 PM EDT Sun Jul 7 2024 By Monday morning, cutoff 500mb high will be over the SW CONUS with a ridge axis extending NNW along the Pacific coast of North America, leading to 500mb height anomalies of up to +18 over the Vancouver area per the 12Z GEFS. The high will remain largely stationary throughout the week, but the ridge axis to the north will rotate through the early portions of the week as a Gulf of Alaska trough will kick the ridge axis to the east. For the early portions of the week, the weak shortwaves spilling down from the peak of the ridge and with some help from diurnal heating, will allow for daily thundershower chances until the ridge axis progresses far enough east for a surface high pressure to dampen precipitation chances. The remnants of Beryl may throw a wrench in the forecast as it passes south of the UP in the back half of the week, but regardless, some hotter weather will return to the UP for the weekend with 90s not out of the question (10-25%) for typical hot spots. To begin the week, one of the aforementioned 500mb shortwave troughs will sweep over the UP on Monday, supporting surface troughing of around 1010mb. This will certainly help force some showers and thunderstorms and 12Z HREF mean SBCAPE does climb to over 1000 J/kg over the interior west and central UP. However, with only around 20kt of bulk shear, storms will likely be disorganized, so only garden variety pulse thunderstorms are expected. This is shown in the very scattered pattern shown in the HREF reflectivity plots. Timing-wise, most of the HREF members show initiation around 18Z Monday with a pretty sharp dropoff in shower coverage and intensity after sunset. Tuesday looks to be yet another day with a shortwave passing over the UP with diurnal thundershowers expected, but PoPs are lower than the previous day (20-50% instead of 40-80%) thanks to a weaker shortwave providing less PVA and overall height rises occurring coincident with tropa. With the 00Z LREF still showing mean CAPE values around 500 J/kg, there are chances (~30%) of thunder, but should be well sub-severe. The complications come Wednesday through the end of the week as the ridge axis moves over the Canadian Prairie and forces a 1015-1020mb high pressure that approaches the Upper Great Lakes through the day Wednesday. However, the remnants of Beryl will swing northeast after making landfall in TX, with the majority of deterministic and ensemble guidance bringing the remnants through the Lower Peninsula of Michigan. The strength and path of both Beryl and the ridge will have implications on the forecast through the end of the week. For now, the current forecast reflects the solution that the high pressure prevails over at least Lake Superior into the weekend, though the 12Z GEFS still shows a 10-20% chance of the remnants of Beryl passing within 200 km of the eastern UP, so the forecast is definitely not set in stone at this point. However, confidence is increasing that after Beryl`s remnant low passes through the Great Lakes and flow aloft shifts from northwesterly to be more westerly, hot temperatures could return to the UP, with the NBM showing about a 25% chance of isolated 90 degree highs and 5-10% chance of more widespread 90s highs. && .AVIATION /00Z TAFS THROUGH 00Z TUESDAY/... Issued at 727 PM EDT Sun Jul 7 2024 VFR prevails at all TAF sites through this period. TSRA is ongoing to the east, south, and west of IWD this afternoon with about a 1-in- 3 chance of thunder reaching the vicinity of CMX. Overnight, VFR is most likely at all sites following the end of showers, though each site has around a 20% chance of fog, which if fog forms, could drop visibility/ceilings to IFR or lower. VFR then will continue through the morning until pop-up TSRA is expected in the afternoon, with the highest chances of SHRA (~70%) and TSRA (~40%) at SAW with lower probs at CMX and IWD. && .MARINE... Issued at 337 PM EDT Sun Jul 7 2024 Light winds of generally 20 knots or less continue through this week as high pressure ridging over the western US slowly drifts eastwards throughout the forecast period. That being said, some thunderstorms are possible across the lake this afternoon through tonight, and then along the nearshores Monday and Tuesday. Wave heights will remain below 2 feet through the duration of the forecast period. && .MQT WATCHES/WARNINGS/ADVISORIES... Upper Michigan... None. Lake Superior... None. Lake Michigan... None. && $$ UPDATE...Thompson SHORT TERM...MZ LONG TERM...GS AVIATION...GS MARINE...GS/TAP
Area Forecast Discussion
National Weather Service Raleigh NC
928 PM EDT Sun Jul 7 2024 .SYNOPSIS... A weak frontal zone extending from the Chesapeake Bay into the Piedmont of the Carolinas will linger and weaken before dissipating by Tuesday. Mid and upper level high pressure will then build across the area before another cold front approaches late in the work week. && .NEAR TERM /OVERNIGHT/... As of 928 PM Sunday... The convection has mostly ended across central NC with some lingering rain patches attm, as the sfc front has slipped south and now extends from approx the CLT region ENE to KGSB and then north to the ORF area. Cooler sfc air behind the front is evident in latest sfc obs with readings in the lower 70s and even some upper 60s temps currently across our northeast Piedmont and northern Coastal Plain zones, with mid-upr 70s across much of the rest of central NC except some lingering 80s readings near the SC border. Will make a few tweaks to forecast temps overnight to account for current trends. Otherwise, the rain should gradually taper off after 06Z tonight as both instability and larger-scale forcing wanes. Until then, in additions to some lingering patchy rain, we can`t completely rule out a few widely sct tstms across our southern-most zones where the front hasn`t yet cleared the area. And it`s also worth noting that several MCVs across the Carolinas and Southeast states...as noted in current water vapor imagery, including one notably just west of the CLT area, appear to be drifting slowly to the southeast...and thus should have limited impact on our weather overnight as they should stay south of our area. Finally, the latest HRRR suggests some stratus will continue to develop and expand overnight across much of the Piedmont region, perhaps extending all the way toward I-95... this stratus formation occurring over areas that received the heavier rain earlier today. && .SHORT TERM /6 AM MONDAY MORNING THROUGH MONDAY NIGHT/... As of 250 PM Sunday... * Continued shower/thunderstorm chances, albeit it with lower areal coverage * Brief periods of heavy rain likely the primary threat with any storms that develop We should have a very similar synoptic setup across the area tomorrow with PW`s still running around 2 to 2.2". The presence of a stalled surface boundary may be lacking though and with only a lee trough and sea breeze to contend with, the overall triggering mechanisms for convection may ultimately be the limiting factor. Storms are once again favored across the western Piedmont along with the Sandhills/southern Coastal Plain, with lesser chances elsewhere. Storms are likely to be outflow dominant and pulse-type in nature given very weak steering flow around 15kts or less. While wet microbursts would be a possibility with any storms that approach severe limits, locally heavy rainfall from slow moving/training storms would likely be the primary threat tomorrow. However given relatively limited areal coverage, we shouldn`t need any flood watches. PoPs in the 20-40 percent range area-wide are the general consensus from the NBM, HREF, and other global models and this seems reasonable at this point. Temps will be on par with today`s values with highs in the upper 80s/lower 90s with lows falling into the lower 70s. && .LONG TERM /TUESDAY THROUGH SUNDAY/... As of 250 PM Sunday... * Typical summer pattern through the weekend * Some storms possible Tuesday/Wednesday, becoming more numerous late in the week Precip chances look to decrease on Tuesday as an offshore upper low off the NC coast dives southwestward toward Florida. In its wake, mid level heights appear to increase by a few meters and this may be enough to further inhibit storm development across the area. While similar PW`s will be in place area-wide, very limited forcing and instability outside of an area near a lee trough across the western Piedmont should keep storms isolated/widely scattered in nature. Meanwhile, the remnant circulation and moisture associated with T.C. Beryl will be drawn inland and absorbed into a longwave trough approaching the western Great Lakes later this week. This will spawn a relatively deep surface cyclone that will track northward across the Great Lakes into southern Ontario. An attendant surface boundary will make an eastward run at the mountains, but likely stall/wash out before it makes it across. However the remnant boundary and/or lee troughing will likely result in an area of enhanced surface convergence which will be stall out and be slow to exit the area. Nearly all global models suggest a plume of increased PW`s will be drawn inland from off the SE coast on Wednesday, interacting with and serving as a necessary ingredient for increased shower and thunderstorm coverage to close out the week. There is a general consensus among the ensembles that Thursday and Friday could be particularly active as a weak surface low develops along the stalled surface boundary to our south and tracks through central NC. Looking at the 100 member grand ensemble of the Canadian, GFS, and EC ensemble forecast systems, nearly 80 percent suggest precip across the area on Thursday and nearly 90 percent on Friday, which is an unusually high amount of agreement for this time of year at this lead time. Of course exactly how much rain will fall, and exactly where the surface boundary and low track set up, is still TBD but the trend of increasing late-week PoPs will continue. Precip chances should remain elevated (although slightly lower as compared to Thursday/Friday), as we get into the weekend. Temperatures this week should be within a few degrees of normal. Through mid week with mid level ridging sneaking in from the east, temps should make a solid run into the mid 90s area-wide and it is on these days (Tuesday and Wednesday) where heat indices could make a return to dangerously high values. However increased cloud cover and precip chances will knock readings back into the mid/upper 80s Thursday, especially Friday, and possibly into Saturday as well before returning to normal by Sunday. Lows throughout the period generally upper 60s to mid 70s. && .AVIATION /00Z MONDAY THROUGH FRIDAY/... As of 740 PM Sunday... Through 00Z Tuesday: Convection is slowly diminishing in coverage this evening; however we are seeing a variety of flt conditions across central NC attm depending on where the rain is falling. As the evening progresses into the overnight hours, the rain should mostly end, however across much of the Piedmont we expect a shield of stratus to form, which will lower flt conditions aob IFR after 05Z across much of the Piedmont, including KINT, KGSO, and KRDU, and possibly extending as far east as KRWI and KFAY. This stratus will linger through about 14Z before cigs slowly lift back to VFR by 17 or 18Z Monday. Winds will generally be aob 10kt, but direction will be highly variable based on outflow boundaries, and the locations of the synoptic front which currently extends from KAFP to KPOB to KGSB. After 00Z Tuesday: A rather typical summer pattern of scattered afternoon and evening showers and storms along with some late night and early morning stratus and fog is expected through the period with the coverage of storms and restrictions expected to uptick on Wednesday and increase for Thursday and especially Friday. && .CLIMATE... Record High Minimum Temperatures: July 7: KGSO: 73/2019 KRDU: 77/1900 KFAY: 78/2017 July 8: KGSO: 76/2010 KRDU: 78/1986 KFAY: 79/2012 July 9: KGSO: 76/1987 KRDU: 74/2014 && .RAH WATCHES/WARNINGS/ADVISORIES... None. && $$ SYNOPSIS...Blaes NEAR TERM...np SHORT TERM...DL LONG TERM...DL AVIATION...np CLIMATE...RAH
Area Forecast Discussion
National Weather Service Reno NV
147 PM PDT Sun Jul 7 2024 .SYNOPSIS... * Prolonged heatwave continues through Thursday. Gradual cooling trend late week into the next weekend. * Potential increase in breezes and thunderstorm chances starting Thursday into next weekend, yielding fire weather concerns. && .DISCUSSION... * The heatwave continues with moderate to major HeatRisk forecast for many lower elevation areas through Thursday. One trend we`ve seen is with very dry air persisting, overnight lows will have a tendency to be below NBM guidance. Fairly pronounced in mountain communities, which can mitigate the impacts of daytime heat and yield minor-moderate HeatRisk levels. Given this, we are going to end the Heat Advisories for Tahoe and most of the Eastern Sierra zone past today. Heat Warnings will continue for W Nevada along with Advisories for NE California and Mono below 6000` with plenty of record highs and warm lows to fall the next few days. * Wildfires to our immediate west in the Sierra are not showing a lot of activity again today. The 12z HRRR Smoke is probably overdone. So barring a significant uptick in fire activity, we`re not anticipating appreciable haze/smoke impacts on our side of the mountains. The Shelly Fire west of Mt Shasta has produced some high altitude smoke that is passing overhead today, and could again tomorrow. * Confidence is increasing in the afternoon/evening winds bumping up into potential critical fire weather category starting Thursday as the upper ridge slides to the east. Gusts on the order of 30-40 MPH possible each day in the typical areas from Susanville-Reno- Mammoth. NBM has 40-50% chances of gusts 35+ MPH each day Thursday into the next weekend, which this far out is a decent signal. * Of lower confidence but still worth tracking is a potential moisture resurgence northward into our area as that ridge moves eastward. NBM t-storm POPs rise into the 10-25% range starting Friday in both mountains and valleys. With our ongoing heatwave further drying vegetation, any lightning could result in new fire starts. -Chris && .AVIATION... Typical afternoon W/NW breezes with VFR conditions expected through Tuesday. Hot temperatures could result in density altitude concerns for some aircraft each afternoon into next week. -Chris && .CLIMATE... Record High and Warm Low Temperatures for July 7th-13th at Reno- Tahoe International Airport (KRNO) -------------------------------------------------------------------- Date Forecast(High/Low) Record High(Year) Record Warm Low(Year) ------ ----------------- ---------------- -------------------- July 7 106/69 102F (2014) 68F (2001,2004) July 8 105/70 104F (2017) 71F (2014) July 9 105/69 104F (2021) 69F (2021) July 10 104/68 108F (2002) 72F (2021) July 11 104/68 108F (2002) 74F (2014) July 12 103/69 104F (2005,2021) 74F (2002) July 13 100/69 103F (2014) 70F (2014,2018) Current record for consecutive days of 100F or greater at KRNO is 10 days, set in July 2021 and July 2005. With 3 days of 100+ so far in this streak, there is a good chance of tying this record but whether or not we break it is less certain. The record for consecutive days of 105 or greater is only 2 days, which has occurred 6 times in climate history, most recently July 2023. Today will tie that record. && .REV Watches/Warnings/Advisories... NV... Heat Advisory until 11 PM PDT this evening NVZ002. Excessive Heat Warning until 10 AM PDT Friday NVZ001-003>005. CA...Heat Advisory until 10 AM PDT Friday CAZ070-071-073. Heat Advisory until 11 PM PDT this evening CAZ072. && $$