Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 05/24/20

Area Forecast Discussion...UPDATED
National Weather Service Aberdeen SD
950 PM CDT Sat May 23 2020 .UPDATE... Issued at 947 PM CDT Sat May 23 2020 Made some changes to the pops to account for convection trends so far this evening. Best chance for severe would appear to be Missouri valley where stability progs and developing LLJ support as much. Further east showers and some storms are likely, but the risk for severe looks low over northeast SD. Southeast SD is probably where the best support is for a long lived MCS with occasional severe weather. && .SHORT TERM...(This Evening through Sunday Night) Issued at 345 PM CDT Sat May 23 2020 Storms developing this afternoon across western sd along a stationary front. Expect thunderstorm development to be slow to the east into our western cwa this evening and into tonight as this focus area/front moves/pushes east with a surface low pressure area lifting along it. The latest spc analysis and rap forecast cape and deep layer shear show western sd with the best ingredients for severe weather into this evening. The good instability and shear build/move into central sd into the late evening and then weaken diminish through the night into our eastern cwa. Therefore, expect the best thunderstorm and rain coverage to be in our western cwa with the storm coverage diminishing through the night into the eastern cwa with more showers late tonight. Otherwise, there will probably be a break in the action Sunday morning in the cwa with new development Sunday afternoon and night with the main upper level low pressure trough out west bringing more lift to our region. Also, some sunshine under the colder air aloft will bring some good buildup of instability Sunday afternoon and evening. The surface cold front should push through most of the region through Sunday afternoon with possible breezy conditions in the western cwa. Highs on Sunday will range from the upper 60s far west to the upper 70s far east. .LONG TERM...(Monday through Saturday) Issued at 345 PM CDT Sat May 23 2020 Differences show up right away in models in regards to Monday`s weather. 12Z EC shows a surface wave moving northward along the boundary and bringing showers and thunderstorms to the eastern CWA, whereas the GFS and Canadian solutions keep things further east and mostly dry. Have chance POPs in right now, but may need to make adjustments over the next couple models runs based on what happens. Otherwise, no major changes to the extended period forecast. && .AVIATION...(For the 00Z TAFS through 00Z Sunday Evening) Issued at 616 PM CDT Sat May 23 2020 Terminals KABR,KATY,KPIR,KMBG KPIR/KMBG are under the threat of showers/thunderstorms this evening, with severe weather possible, especially around KPIR. Further east, KABR and KATY will see some late night showers and storms, but severe weather appears unlikely. The showers could linger into the morning on Sunday. ***Construction to improve the taxiway for runway 13 at the KPIR terminal may cause an occasional temporary visibility reduction due to blowing dust (bldu), mainly during daytime hours UFN. && .ABR WATCHES/WARNINGS/ADVISORIES... SD...None. MN...None. && $$ UPDATE...TDK SHORT TERM...Mohr LONG TERM...TMT AVIATION...TDK
Area Forecast Discussion
National Weather Service Binghamton NY
908 PM EDT Sat May 23 2020 .SYNOPSIS... A weak cold front will move through Sunday night and trigger scattered showers and storms. High pressure builds across much of the Northeast through the week with warming temperatures and a chance of afternoon showers and storms nearly everyday this week. && .NEAR TERM /THROUGH SUNDAY NIGHT/... 9 pm update...Forecast remains mostly on track. Made some minor changes to sky cover. With all the low clouds just about gone from the region and just a thin cirrus layer overspreading the area that you can see stars through, so have made conditions overnight just partly cloudy. Only exception will likely be from Luzerne County eastward to Pike County, as easterly flow is trying to push a marine layer into the area through the early morning hours. 6 pm update...Shower activity has really diminished over the past hour as upper level low continues to push off to the east. Have lowered PoPs through this evening with the greatest chance for any showers across NE PA until sunset. Only other changes made at this time was to slightly decrease cloud cover based on latest METSAT and observations. 320 pm update... Main concerns in the near term are focused on the persistent/redeveloping showers and storms from the srn tier of NY into ne PA this afternoon...the cool and quiet weather tonight and the next round of scattered showers and storms Sunday night into early Monday morning. A trailing wing of the cut-off upper low currently off the srn Jersey coast is sweeping east to south across the region this afternoon...and interacting with a fair amt of instability and available deep moisture. Latest RAP mesoanalysis shows around 500-1000 J/kg of CAPE across ne PA...steepening low level lapse rates due to some breaks in the cloud cover, and shallow mid level lapse rates as the upper low moves out. PWATs are still around 1-1.3 inches and capable of supporting convection with echo tops above 30k ft...which may be able to drop a half to 1 inch of rain in a short period of time, especially for those storms that either train over the same area or become quasi- stationary. So far, the convection has been fairly progressive this afternoon, which has limited the potential for any hydro/flooding issues. In addition, the rain this afternoon is occurring over an area that was void of the mod/steady rain from last night. The trends should remain the same through the rest of the afternoon and into the early evening as the drier and more stable air moves in behind the departing low. Showers and storms are expected to diminish in intensity and coverage...and come to an end just before or around sunset. A small scale surface high builds in off the Maine coast tonight and combines with the low to the south to induce a solid east wind off the Atlantic, which is expected to push all the way into central NY. There is still some uncertainty in exactly what this will result in, but the consensus is that a cool, but dry air mass will create favorable conditions for temperatures down into the 40s east of I-81 in NY and PA...but remain in the 50s to the west. Ridging aloft and the surface high to the east will be the primary factors in keeping weather conditions quiet through most of the day Sunday. Winds shift to the south/se and allow for a slightly warmer air mass. Temperatures should climb into the 70s for much of the area with relatively low dew the 50s...making it feel quite comfortable. The next round of showers and storms is expected to arrive from the west Sunday evening/night as an upper short wave cuts across the Great Lakes into nrn NY and drags a weak cold front through the area. There could be a decent amt of instability combined with enough forcing aloft to trigger some embedded thunderstorms through the overnight hours. && .SHORT TERM /MONDAY THROUGH MONDAY NIGHT/... 3 PM Update... A chance for showers, perhaps with some rumbles of thunder, will continue through Monday afternoon as a weak midlevel trough passes through the area. As a surface high remains in control from New England through the mid Atlantic, precipitation will have trouble being able to spread too far eastward, with our chances likely staying contained to our western NY zones. Modest instability aloft will keep a chance for thunder in the forecast, but this would have to overcome a developing capping inversion as a ridge builds back in behind the passing wave. This will help to wind down chances for lingering showers overnight Monday. Much of the area will be dry for Tuesday with the apex of the ridge generally over eastern NY and PA and inhibiting convection over those areas. Some shower/thunderstorm activity would be possible across our western zones, but being diurnally driven with no real forcing mechanism, organized convection is not expected. Otherwise, expect a warming trend to continue into the short term period as temperatures reach into the upper 70s and even lower 80s across the Finger Lakes and Ontario lake plain. Temperatures fall back into the 50s and 60s Monday night before peaking in the 80s across most of our forecast area Tuesday - with some of the valleys possibly reaching into the mid/upper 80s! Temperatures fall back into the 60s Tuesday night. && .LONG TERM /TUESDAY THROUGH SATURDAY/... 3 PM Update... Wednesday will be much the same as Tuesday as we remain under the control of the upper level ridge that is slowly shifting more offshore. This will allow a chance for daytime convection mainly across our western forecast area as temperatures peak in the 80s and dewpoints hover in the 60s. As the ridge will be offshore Thursday with a warm, moist airmass in its wake, any weak ripples in the flow could touch off some showers and thunderstorms. Chances will continue Thursday night through Friday as a trough moves into eastern Canada. Otherwise, temperatures continue to peak in the upper 70s and lower 80s - with some of the guidance hinting at cooler temperatures Friday night as the aforementioned trough drags a cooler airmass into the region. && .AVIATION /01Z SUNDAY THROUGH THURSDAY/... Upper level low continues exiting out into the Atlantic. Showers have come to an end with clearing skies across the region. Even with the wet conditions from recent rain, have left any fog out of the forecast tonight, as low level flow should be just strong enough to hinder fog development. No forecast model guidance is hinting at any valley fog at this time either. So VFR conditions are expected through the forecast period. Outlook... Sunday afternoon through Tuesday...Likely VFR. Wednesday and Thursday...Chance of showers and storms with brief restrictions possible. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...None. NY...None. && $$ SYNOPSIS...BJT NEAR TERM...BJT/MPK SHORT TERM...HLC LONG TERM...HLC AVIATION...MPK
Area Forecast Discussion...UPDATED
National Weather Service Brownsville TX
752 PM CDT Sat May 23 2020 .DISCUSSION...Updated for latest aviation discussion below. && .AVIATION...Conv firing off to the west of the RGV is leaving behind plenty of cirrus blow off over the region moving off to the ESE. Meanwhile, vsbl satl imagery shows some SCT-BKN low clds moving in off of the Gulf waters. Expect these MVFR ceilings to become a little more widespread and lower later this evening and tonight for all 3 RGV airports. The latest 88D mosaic across the western areas of the EWX CWA extending down south into north central Mex. A single large hail producing t-storm is firing about 115 NM WSW of the KBRO radar. This single cell is drifting slowly SE and is not much threat to the RGV at this time. The HRRR conv guidance seems to be initializing pretty well on this ongoing conv. This model generally keeps the RGV clear of the conv until closer to sunrise Sun. So for now will leave out any mention of conv for the current TAF issuance until the later sections of the TAFs where will include some PROB30 remarks. && .PREV DISCUSSION... /issued 309 PM CDT Sat May 23 2020/ SHORT TERM (Now through Sunday Night): Satellite imagery and surface observations continue to indicate some fair weather CU and moderate to gusty winds across deep south Texas this afternoon. Temperatures this afternoon generally range from the low to mid 90s inland and mid to upper 90s near Falcon Lake. Adjusted high temperatures a couple of degrees warmer for the rest of the afternoon due to current trends. Brownsville radar currently shows some convection across the higher terrain of northeast Mexico. Latest satellite imagery indicates convection developing in associated with a 500 mb shortwave moving over northern Mexico and the Texas Big Bend region. This mid to upper level feature will strengthen over central Texas through the day on Sunday. A weak trough axis and vorticity will swing over south Texas tonight. However, most CAMs models develop storms far west late tonight before weakening as the convection approaches the CWA. However, low confidence continues for rain chances for tonight and Sunday due to differences in the model guidance. Brownsville upper air data this morning indicate a PWAT value of 1.62 inches. PWATs will increase tonight to between 1.8 to 2.0 inches and remain high through Sunday night. Another stronger mid- level support is expected to arrive Sunday night. Any convective would likely contain locally heavy rainfall, with minor flooding possible, especially in low lying and poorly draining areas. SPC Day 2 convective outlook has the entire CWA outlined in a marginal risk for severe weather Sunday and Sunday night. Also, WPC has most of the CWA into a slight risk for excessive rainfall Sunday into Sunday night. The best rain chances and potential of heavy rainfall appears to be Sunday night into Sunrise Monday as the mid level energy passes overhead. LONG TERM (Monday through Saturday): The long term period continues to look wet and unsettled. A deep mid to upper level trough will dig into the Central Plains on Monday. As it continues to deepen into the Southern Plains, a mid level cutoff low will form at its base, effectively detaching itself from the mid level westerly flow. This will allow the cutoff low to camp-out over the state of Texas through the end of the period. With ample surface moisture streaming in from the Gulf over the region and conditional instability in place, the nature of the convection that forms will depend primarily on the timing and location of mesoscale interactions...namely, the vort maxes that circulate around the low as well as any surface features including convective outflows. While there is generally good agreement between the models on the wet forecast through the period because of this general pattern, the exact onset, location, and duration of the showers and thunderstorms that may develop is very hard to forecast at this time. The Weather Prediction Center (WPC) has included all of Deep South Texas and the Rio Grande Valley in a marginal risk for excessive rainfall on Monday and Monday night as the first round of mesoscale features interact in the long term, but the potential for local areas to receive flash flooding conditions will likely continue through Wednesday morning. The better rain chances look like they will be concentrated mostly to our north through the period, but WPC`s Day 1-7 QPF shows most of Deep South Texas receiving 2.50" to 3.0" of total rainfall through 7 AM CDT next Saturday, but locally higher amounts are possible. This is likely to change as we get a better understanding of the mesoscale features driving the convection through the period. The best rain chances for our area look to be on Monday through Tuesday and again late in the week, but at least slight chance PoPs will continue through the entire period at this point. The potential for isolated strong to severe thunderstorms continues for Monday through Tuesday night when instability is the greatest for our area, but remains a low probability at this point. The Storm Prediction Center`s Day 3 Severe Weather Outlook only has Deep South Texas in a general thunderstorm risk. Temperatures next week will continue to depend on the cloud cover and any rain and thunderstorm development, areal coverage and longevity. MARINE: Now through Sunday Night...Buoy 42020 reported east- southeast winds around 14 knots gusting to around 18 knots with seas slightly under 4.9 feet with a period of 7 seconds at 1420 CDT/1920 UTC. The pressure gradient is expected to weaken as broad high pressure across the Gulf moves further northeast. Moderate southeast winds and moderate seas will prevail through the period. Small Craft Caution conditions are likely across the bay Sunday afternoon due to winds. Small Craft Caution to low end Small Craft Advisory conditions are possible across the Gulf of Mexico waters due to elevated winds and swell through Sunday night. Monday through Saturday...Elevated seas of 3 to 5 feet will start off the week and generally subside through the period to 1 to 3 feet. Showers and thunderstorms will be possible on and off through next week, and localized winds and seas will be affected by any outflows produced by any strong storms that may develop. && .BRO WATCHES/WARNINGS/ADVISORIES... TX...None. GM...None. && $$ This product is also available on the web at: HTTP://WEATHER.GOV/RGV Short Term/Aviation...60 Long Term/Upper Air...65
Area Forecast Discussion
National Weather Service Grand Forks ND
1007 PM CDT Sat May 23 2020 .UPDATE... Issued at 1004 PM CDT Sat May 23 2020 Continuing to see showers with a few embedded thunderstorms across western portions of the Devils Lake basin with HRRR suggesting that the activity will continue for a couple more hours as MUCAPE around 1000j/kg fuels the activity. UPDATE Issued at 645 PM CDT Sat May 23 2020 Line of convection has developed this evening from near Leeds ND and northward. With weak shear expecting the slow motions to the north northeast with localized brief heavy downpours and possibly some small hail and gusty winds. This activity will remain across the Devils Lake basin for the evening. The light precipitation across the MN lakes and trees has ended. && .SHORT TERM...(This evening through Sunday night) Issued at 235 PM CDT Sat May 23 2020 Lower level clouds continue dissipating this afternoon, with mid- level cloud cover gradually diminishing from west to east. Shower activity is currently ongoing in western portions of ND with the expectation of a slow eastward progression along a frontal boundary this afternoon. Ahead of the primary theta-e gradient, we could see a few strong storms develop later this afternoon into the early evening. CAMs and mesoanalysis indicate CAPE values in the 2000 to 2500 J/Kg range across much of central North Dakota as clearing takes place and afternoon heating becomes a factor. Instability sharply drops heading east, but there remains enough to facilitate a continued mention of potentially impactful strong thunderstorms this afternoon and evening. Tonight will be quiet across much of the area, with the Devils Lake possibly seeing a chance for ongoing thunderstorm activity. Lows will fall into the 50s. Thunderstorm chances increase for Sunday across much of the forecast area with activity stretching into Monday morning. At this time, there is a conditional risk for isolated strong storms Sunday afternoon, mainly for west-central Minnesota. .LONG TERM...(Monday through Saturday) Issued at 235 PM CDT Sat May 23 2020 Monday through Wednesday...The upper trough moving through the Dakotas will continue to bring a decent chance for precipitation at the start of the week. Some showers lingering along the backside of the surface low, but there should be enough instability by afternoon for some thunderstorm activity, although deep layer shear stays in the 20-30 kt range so do not think our severe chances are that high. Clouds and some cold air advection on the backside of the surface low will help keep temps in the 60s to low 70s Monday, with some upper 40s Monday night as drier air moves into the area. Another trough moving through Canada Tuesday could bring some stray convection into our northern counties, but for the most part think the better chances will be with the forcing to the north. The digging trough will help push a trough axis/front into the CWA on Wednesday, so have POPs increasing a bit for anything developing along the boundary. Thursday through Saturday...Northwesterly flow aloft sets up, with some model solutions showing ridge riders and some not. The ensembles do not have any strong signal for precipitation, so kept the blended solution of sub 20 percent POPs going. Thursday will see surface high pressure and temps will stay close to the 70 mark. However, rising heights Friday and Saturday should bring readings up to or slightly above seasonal averages. && .AVIATION...(For the 00Z TAFS through 00Z Sunday evening) Issued at 645 PM CDT Sat May 23 2020 Went ahead and added VCTS to DVL this evening. MVFR CIGS expected to develop once again overnight primary at BJI and possibly at TVF and DVL. Rain showers possibly with thunder expected to develop or move into the DVL first overnight and then into the valley around mid day. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...None. MN...None. $$ UPDATE...JK SHORT TERM...Lynch LONG TERM...JR AVIATION...JK
Area Forecast Discussion
National Weather Service Goodland KS
544 PM MDT Sat May 23 2020 .UPDATE... Issued at 456 PM MDT Sat May 23 2020 Updated the forecast to include the Tornado watch this afternoon/evening spanning the CO/KS border area and extending northeast into far SW Nebraska. Increased PoPs a bit along and ahead of the dryline where storms are starting to fire and towards the direction of expected storm prorogation. && .SHORT TERM...(This evening through Tuesday) Issued at 200 PM MDT Sat May 23 2020 Dry line beginning to take shape over northeast Colorado with a westerly wind component and dew points dropping into the 20s and 30s. The dry line is forecast to move eastward through late afternoon and be the focus for isolated thunderstorms. If storms develop, the environment will be favorable for supercells capable of producing large hail, damaging winds and tornadoes. Isolated is the key word here, as CAMs continue to suggest only one or two cells developing. Cirrus is a little more persistent than forecast, somewhat limiting instability, but latest RAP shows CIN eroding by 21z. Unless thunderstorm coverage is more than expected, will probably handle it with local warnings as opposed to a watch per coordination with SPC. Further north in the Nebraska panhandle, forcing will be stronger resulting in better coverage, but that complex is now expected to remain north of the local area, so will have no POPs after about 04z tonight. Cold front will move through and just about clear the area by 12z. Breezy northwest winds can be expected through the night behind the front. Low temperatures will range from the upper 40s in northeast Colorado behind the front to the lower 60s in Norton and Graham counties ahead of it. Sunday the area will be post frontal. There is a low chance that the front will hang up/or be just near the far southeast part of the area when thunderstorms develop on it around 21z. However, think more likely the front will be clear of the area and not be a factor. Instead will look west to the Front Range where large complex of rain/isolated thunderstorms will develop as main upper trough axis emerges. Those storms will move across the area Sunday night. Main hazards will be wind during the evening hours associated with any cold pools/bowing structures, as well as heavy rain, especially after midnight. Global models suggesting some areas will receive 1 to 1.5 inches Sunday night. High temperatures Sunday afternoon will range from the upper 60s to upper 70s and lows Sunday night in the middle 40s to lower 50s. Upper trough will be slow to move out on Monday. It will be cloudy and cool with lingering rain/showers likely. Not expecting severe storms due to lack of instability. High temperatures will be in the 60s, and may be a bit too warm with clouds all day. Coolest guidance is in the upper 50s to lower 60s which may be in the right direction. Precipitation will end west to east Monday night as upper trough finally starts to move out. Low temperatures will be in the 40s. A few showers may linger into Tuesday in far eastern areas, Norton to Hill City, but otherwise dry and warmer with high temperatures in the 70s and light winds. Temperatures will dip back into the 40s for Tuesday night. .LONG TERM...(Wednesday through Saturday) Issued at 216 PM MDT Sat May 23 2020 A 500mb closed low retrogrades across the southern Plains slowly Wednesday through Saturday and weakens as ridging pushes into the central U.S. At the surface, high pressure sits over the central Plains. A cold front stalls over the northern Plains by Saturday. The extended forecast period is dry but at this time, no elevated fire weather concerns. High temperatures will range from the upper 70s to mid-80s and lows will be in the 50s. Skies will be mostly sunny to partly cloudy throughout the extended forecast period. && .AVIATION...(For the 00Z TAFS through 00Z Sunday evening) Issued at 507 PM MDT Sat May 23 2020 VFR conditions are expected at GLD through the 00Z TAF period. Southeast winds overnight will turn north after 11Z with he passage of a cold front. North winds will increase and become gusty after 17Z. Scattered thunderstorms are expected after 21Z. MCK will remain VFR through the 00Z TAF period. Southeast winds tonight will turn northerly early Sunday after 08Z with the passage of a cold front. Between 04Z-10Z, LLWS is expected with winds at 1kft AGL of 35kts out of the southeast turning to the southwest after 08Z. By 10Z, LLWS will diminish as winds turn north and increase. Scattered thunderstorms are expected after 21Z. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...Red Flag Warning until 8 PM MDT this evening for KSZ027-041. CO...Red Flag Warning until 8 PM MDT this evening for COZ252>254. NE...NONE. && $$ UPDATE...LOCKHART SHORT TERM...024 LONG TERM...NEWMAN AVIATION...LOCKHART
Area Forecast Discussion...UPDATED
National Weather Service North Platte NE
621 PM CDT Sat May 23 2020 .SYNOPSIS... Issued at 305 PM CDT Sat May 23 2020 H5 analysis from earlier this morning had an active pattern noted across the CONUS. Closed lows were noted over central PA, central Iowa and a third system over far northern Utah. The third system over Utah, had a trough extending south into western Arizona and far southern California. At midday, the Utah low, was now located over west central Wyoming per the latest WV imagery. At the surface: Low pressure extended from far southeastern Wyoming into southeastern Colorado. A dryline extended from west of Limon Colorado into the western Texas panhandle. South southeast of the surface low in SE Wyoming, a weak convergence boundary was noted and extended to north of Burlington Colorado. Skies were partly to mostly cloudy this afternoon across the area and 2 PM CDT temperatures ranged from 72 to 76 degrees. && .SHORT TERM...(This evening through Sunday night) Issued at 305 PM CDT Sat May 23 2020 Tonight thorugh Sunday night...Precipitation chances tonight and Sunday night and the threat for severe storms tonight are the main forecast challenges in the near term. For tonight: The 12z LBF Raob sounding from this morning indicated a strong capping inversion with a convective temperature in the middle 80s. Highs this afternoon are expected to reach the middle to upper 70s. Forecast soundings from further west in far southwestern Nebraska and the eastern Nebraska panhandle, indicate the capping inversion remaining in place through peak heating this afternoon. That being said, not expecting much in the way of storm initiation across the forecast area late this afternoon. Further west though, the latest NAM12 soln is indicating a weakening cap around 21z Saturday. The last few hourly runs of the HRRR develops convection SE of Sterling Colorado around 21z, approaching far SW Nebraska in the 5 to 6 PM CT time frame this evening. Deep layer shear of 35 to 40 KTS will adequate for supercells. Mid level lapse rates (H70-H50) are very steep across sw and west central Nebraska. This would favor large hail and even a very large hail threat across far western portions of the forecast area through 01z Sunday. As for the tornado threat, the capping inversion is problematic. Also low level helicities are meager. That being said, the tornado threat appears limited and confined to far western portions of the forecast area in a short window, say 4 to 8 PM CT. As for precipitation chances, they will remain greatest in the northern forecast area. As storms migrate off of the panhandle early this evening, they are expected to congeal into a convective complex, enhanced by the development of a low level jet overnight. ATTM, not too concerned about flooding as the heaviest rain is expected north of areas which saw the heaviest rainfall earlier this week. Later this evening, there will be some wind threat with the convective complex as it tracks east. The latest NAMnest and HRRR solns indicate some bowing storm structures within the convective complex. The H5 low, will lift into eastern Montana overnight into Sunday morning, forcing a front through the area by mid morning. This front will then stall off to the south and east of the forecast area and will be the focal point for showers and thunderstorms Sunday afternoon/Sunday night. Other showers and storms may develop across eastern Colorado Sunday afternoon, INVOF the front and near the base of the H5 trough. Some of this activity may extend into SW then Southern and portions of central Nebraska Sunday night. Have kept pops going in the south, southeast and east Sunday/Sunday night, but trimmed them back in the north as these areas will be well north of the front and appreciable forcing will be very limited in these areas. Skies will be mainly cloudy Sunday which will limit temps to the 60s to around 70 for highs. The h5 low will weaken and meander slowly east into the western Dakotas Sunday night. The front will remain anchored off to the east of the forecast area, so pops will be highest in the east with mainly dry conditions expected in the west and northwest. .LONG TERM...(Monday through Saturday) Issued at 305 PM CDT Sat May 23 2020 The mid range solutions including the ECMWF and GFS from this morning, develop a cutoff low over central Texas into the Arklatex next week. Ridging to the west of this feature will develop from the four corners, north into the northern Rockies by late next week. Moisture will be locked in over Texas with the cutoff, so am expecting mainly dry conditions across the forecast area next week. This shows up in the latest MEX guidance, which is well below climo for pops next week. Temperatures will increase into the upper 70s to lower 80s next week with the ridging off to the west. However with the axis of this feature aligned over the Rockies, the hottest temps should remain west of the forecast area. && .AVIATION...(For the 00Z TAFS through 00Z Sunday evening) Issued at 620 PM CDT Sat May 23 2020 Thunderstorm activity across the Panhandle this evening will move east and expand in coverage across wrn and ncntl Nebraska overnight affecting areas generally north of Interstate 80. Isolated storm coverage is expected along and south of the Interstate. All storm activity should exit the region by 12z Sunday. VFR is generally expected across wrn and ncntl Nebraska thereafter. && .LBF WATCHES/WARNINGS/ADVISORIES... None. && $$ SYNOPSIS...Buttler SHORT TERM...Buttler LONG TERM...Buttler AVIATION...CDC
Area Forecast Discussion
National Weather Service Marquette MI
815 PM EDT Sat May 23 2020 .SHORT TERM...(This evening through Sunday) Issued at 335 PM EDT SAT MAY 23 2020 A warm, and muggy for UP standards, start across the board this morning as increasing high- and mid-level clouds moved in from the south. GOES imagery and RAP analysis show a sfc low across Iowa that is essentially collocated with a shrtwv trof. This trof and assoc sfc low is progged to lift through the Great Lakes region tonight, bringing rain showers and the chance at a thunderstorm or two as well. As this shortwave continues lifting northward, expect cloud coverage to continue to increase. More locally, a few -SHRA popped up as a wave moved across the UP and crossed over the lake breeze. Temperatures were held down into the upper 60s to near 70 across the west and under more sunshine the east climbed to near 80. Tonight, models suggest that sfc low and shortwave will lift through northern Lake Michigan. Models still show quite a bit of different solutions, but the mean of them suggest the chance for -SHRA from Marquette/Dickinson county east. There is a bit more agreement on the chance of -TSRA along Menominee, Delta, and Schoolcraft counties, though. Models show the CAPE tonight is a little elevated, just above the nocturnal inversion, but to the tune of a few 100 J/kg. With little to no shear, and jet dynamics remaining well to the south there isn`t much chance for anything to become significant. As these clouds linger through the night and PWATs are near 1.5 inches, went with a little higher lows for tonight than the going fcst...but still should fall into the mid to upper 50s. Included some patchy fog in this forecast as low-level moisture lingers and weak upslope flow from WI brings an increased chance. Models aren`t all in agreement for fog, but the best chances seem to be across the central where low-level moisture will continue to increase, leading to the best chance to produce some fog. Tomorrow, there may be some linger -SHRA across the east half of the UP in the morning, but then models suggest dry conditions in the afternoon. As the shortwave exits east, models do suggest some shortwave ridging to move in behind it with rising heights. Expecting this to lead to some clearing in the afternoon from west to east, but we shouldn`t tap into any abundant sunshine. Went with the 50th percentile for highs which brings widespread 70s with some low 80s across the downslope-favored areas. With weak synoptic forcing, winds will be generally light, which should allow another lake breeze to develop in the afternoon. Didn`t include any PoPs in the forecast, but given the high Tds expected tomorrow, any afternoon shower or two along the lake breeze seems possible. .LONG TERM...(Sunday night through Saturday) Issued at 335 PM EDT SAT MAY 23 2020 An upper level ridge will strengthen over the eastern U.S as another blocking pattern develops for early next week. An upper level low pressure pushing out of northern Rockies will split with a closed low becoming cut off over the southern plains. Shortwaves ejecting ahead of the upper level low will bring multiple chances for precipitation to the Upper Peninsula through midweek. An upper level trough and cold front arrive for the later part of the week as the eastern high pressure ridge breaks down, bringing cooler and drier air into the area. Sunday night into Memorial Day. A steady feed of gulf moisture will bring low level moisture into the area resulting in continued muggy conditions, with warmer overnight lows and high temperatures in the 70s to low 80s. Cooler temperatures can be expected along the Lake Michigan and Superior shorelines as the lake breeze develops in the afternoon. Ensembles are showing 1.25+ inches of precipitable water with the deterministic GFS indicating values of over 1.5 inches. Multiple shortwaves will affect the area Sunday night into Monday night. These, combined with daytime heating destabilization, should result in multiple opportunities for isolated to scattered showers and thunderstorms, particularly over the western 2/3 of the Upper Peninsula. Shear will remain marginal with instability of 1000 to 2000 J/kg and therefore widespread organized thunderstorms are not expected at this time. The biggest threat will be heavy rain with the higher precipitable water values. Those recreating outdoors for the holiday should keep an eye to the sky. Unsettled conditions continue into Tuesday and Wednesday with a possibility for more widespread precipitation though models still diverge on solutions with the GFS being the wetter solution. Medium range models indicate a fairly significant faster trend with shortwave to usher in cooler conditions late week. Fropa may now occur as early as Wed night/early Thu which would support dry weather returning on Thu along with cooler conditions than currently reflected in this fcst issuance. Dry weather would then follow on Fri, perhaps lingering Sat. && .AVIATION...(For the 00Z TAFS through 00Z Sunday evening) Issued at 814 PM EDT SAT MAY 23 2020 VFR cigs are expected at KIWD and KCMX with the potential for some fog toward daybreak. A Shower may be possible at KIWD late this evening but probability is too low for mention as VCSH and is not expected to drop conditions to MVFR. VFR conditions at KSAW are expected to give way to lowering cigs to MVFR and then to IFR toward Sun morning as additional moisture moves into the area with an approaching weak trough. Showers may also be possible late but the main batch of rain and TS potential should remain to the south and east. Conditions should improve to VFR by afternoon. && .MARINE...(For the 4 PM Lake Superior forecast issuance) Issued at 335 PM EDT SAT MAY 23 2020 Little change to the forecast as winds will be generally light through the period. A few waves will move through the region through the week, but winds are expected to remain on the lighter side. The air mass lifting up over Lake Superior over the next couple of days will gradually moisten, and could result in some areas of fog at times. However, where any showers, and potentially some thunderstorms, develop and track will play a large role in where fog may develop. && .MQT WATCHES/WARNINGS/ADVISORIES... Upper Michigan... None. Lake Superior... None. Lake Michigan... None. && $$ SHORT TERM...JAW LONG TERM...NL AVIATION...JLB MARINE...JAW
National Weather Service Morristown TN
919 PM EDT Sat May 23 2020 .UPDATE... EVENING UPDATE. && .DISCUSSION... Convection has all but ended across the area as this was diurnal based activity. The latest HRRR shows the showers and storms currently across northern Alabama gradually moving toward the southern Plateau and southern TN valley but then fading before entering the CWA. Still have a slight chance POP in place over the next hour or two but then a dry forecast for the rest of the night. Added some patchy and area fog into the grids for the early morning hours. Will send out new zones for fog addition. All other elements appear to be on track. SR && .AVIATION... 00Z TAF DISCUSSION. Mainly VFR at all sites. Convective activity has all but subsided across our area as we lose daytime heating. There is still a slight chance for an isolated shower or storm over the next hour or two near a terminal but not high enough chances to include in TAFs. CHA will be VFR through the period. TYS will see a brief period of MVFR fog tomorrow morning but otherwise VFR. TRI will also see fog tomorrow morning but will go down to LIFR before returning to VFR through the rest of the period. SR && .PRELIMINARY POINT TEMPS/POPS... Chattanooga Airport, TN 66 88 67 86 68 / 20 30 20 50 20 Knoxville McGhee Tyson Airport, TN 65 87 65 85 65 / 20 30 20 50 20 Oak Ridge, TN 64 87 65 86 65 / 20 30 20 50 20 Tri Cities Airport, TN 60 84 62 83 61 / 20 30 20 40 20 && .MRX WATCHES/WARNINGS/ADVISORIES... NC...NONE. TN...NONE. VA...NONE. && $$
Area Forecast Discussion
National Weather Service Paducah KY
958 PM CDT Sat May 23 2020 .UPDATE... Issued at 958 PM CDT Sat May 23 2020 Although difficult to discern without question, there still appears to be weak troughiness or low embedded near a shear zone moving toward the Missouri BootHeel and the southeast Missouri Delta region during the past hour. Convection across northeast Arkansas and west Tennessee loosely support this feature. The recent runs of the HRRR and ESRL HRRR continue to support some northward transport of this localized moisture and instability into west Kentucky later this evening and overnight. Kept a small chance of showers and isolated thunderstorms in place across southern parts of west Kentucky and into southeast Illinois overnight. Although the probability will continue to diminish markedly, cannot rule out a strong wind gust with any thunderstorm that moves into the WFO PAH forecast area. Will leave a mention of an isolated strong storm in the Hazardous Weather Outlook for the remainder of the evening. Otherwise, little if any changes to the sensible weather elements for the remainder of the tonight`s forecast. && .SHORT TERM...(Tonight through Monday night) Issued at 247 PM CDT Sat May 23 2020 Our region will remain in an unsettled weather pattern through the holiday weekend. Coverage has been sparse today, though the HRRR and RAP indicate a few hours of convection late this afternoon across the Pennyrile region north into portions of southwest Indiana. Latest radar shows a couple of cells developing just south of our CWA in west tennessee, and visible satellite shows increasing cumulus development in the Pennyrile, so increased chances through 00z for this area. Will keep slight chance pops across the rest of our area until 00z. Loss of heating should give us dry conditions overnight. A mid/upper level wave will cross our area on Sunday, and with daytime heating and available moisture, we expect better chances of showers and storms across our entire region, especially in the afternoon hours. Small chances will linger across our western half of counties into the early evening. Loss of heating should again give mainly a dry overnight. On Monday, a more substantial mid/upper level trof over the Rockies will be pushing into the Central Plains and a cold front making its way toward the middle Mississippi Valley. This results in even better chances of showers and thunderstorms for Monday, and went with likely chances for Monday afternoon. With the cold front continuing eastward, we will not be getting our nighttime break from the convection, though chances will decrease. We will remain warm and muggy through the period, with highs in the middle to upper 80s and dew points in the middle to upper 60s. Overnight lows will be in the middle to upper 60s, which is 10 to 15 degrees above seasonal normals. .LONG TERM...(Tuesday through Saturday) Issued at 247 PM CDT Sat May 23 2020 The post holiday week forecast continues to look like summer. As we remain in between strong high pressure to our east, and a closing/eventually cut off Low to our west, we will have ample warmth and moisture in the column each day. Instability will continue to be best during the heat of the day, so lacking any triggers, diurnally favored pops will be a lingering trademark in our forecast. The best chance for any assisted lift/focus would come from mesoscale outflow, or perhaps, some energy feeding into western portions of the FA from the Low pressure area to our west, but really, its primary influence will be tapping moisture/producing heavy rainfall/storms across the southern Plains and into the Gulf coast states. There has been some model indication that a more active/progressive northern stream flow will allow for a cold front to slip down into the Ohio River Valley late in the week. If this occurs, this would offer another trigger and lift support and some cooler/drier air post fropa, the effects of which would likely not manifest until next weekend. This is in fact the blend`s approach with a slight downward trend in pop and temps/dew points next Saturday...and we offer no argument against it. && .AVIATION... Issued at 609 PM CDT Sat May 23 2020 At the beginning of the 00z Sunday WFO PAH TAF forecast period, a some middle and high clouds will likely spread over KCGI, KMVN, and KPAH (and possibly KEVV), associated with lift along a deformation zone associated with a minor low/shortwave over central Arkansas this evening. Some high resolution model guidance suggests that there may be convection (showers and thunderstorms) that may approach or impact the KPAH and KCGI TAF sites. Given the uncertainty in the northward extent of the potential for evening convection to these locations, have opted to leave any significant reductions to visibility or ceilings out of the forecast. At this point in time, given the low probability of precipitation through 18z Sunday, decided to continue with a VFR forecast of cloud bases and ceilings and visibilities for the forecast period. The only caveat is from 18z Sunday to 00z Monday on ceilings and visibilities at all WFO PAH TAF sites. This time period may be need to be reassessed in later TAF forecast issuances. && .PAH WATCHES/WARNINGS/ADVISORIES... IL...None. MO...None. IN...None. KY...None. && $$ UPDATE...Smith SHORT TERM...RST LONG TERM...DH AVIATION...Smith
...Update to aviation forecast discussion...

.SHORT TERM...(This afternoon through Sunday night) Issued at 328 PM CDT Sat May 23 2020 For this afternoon and early evening, there remains a conditional chance for thunderstorms. And that condition is generally what would cause a storm to initiate, i.e. lift or forcing. Forecast soundings from the HRRR/RAP/NAM continue to show very little if any inhibition to a boundary layer parcel this afternoon. With the hot and humid air in place, forecast MUCAPE values remain in the 3000 to 4000 J/kg range. And while deep layer shear is rather modest, effective shear around 35KT would be enough for a rotating updraft. So there remains some concern for an isolated severe storm into the early evening. If a storm is able to develop, very large hail and torrential rain would be the most likely hazards. As the low level jet increases this evening, the low level hodograph is progged to expand suggesting there would be a tornado risk around sunset. However confidence in storms developing is low. The last several versions of the HRRR have backed off on developing anything this afternoon. So chances for thunderstorms are slight, but if one develops it could quickly become severe. Later on in the night, there continue to be some indications from the models for convection off the higher terrain to potentially move far enough east to make it into the forecast. The NAM is the most aggressive in showing storms from the dryline in southwest KS moving through central KS. This solution doesn`t have much support from other models. The NAM also look to have some convective feedback in its solution which may explain the more aggressive propagation of convection east overnight. In general there is not a lot of confidence in storms moving this far east overnight since models show little mid level height falls over eastern KS and the nose of the low level jet is progged to set up over central NEB. Have continued with some POPs overnight in case I`m wrong, but have trended them lower. Lows tonight should not cool off to much with good southerly flow and a moist airmass remaining over the area. Think lows will end up in the upper 60s to around 70. For Sunday, chances for precip will be on the increase during the afternoon as there is good consensus for the prefrontal trough to move into central KS by the late afternoon. Meanwhile the upper trough over the Rockies should continue moving east with perturbations likely to lift across the state. Given a very unstable airmass still over central and eastern KS, storms are expected to develop within the low level confluence of the surface trough during the afternoon and continue moving east overnight. Initially storms may be discrete but are forecast to eventually evolve into a linear system. Large hail and damaging winds will be a concern with any storm that forms on Sunday. Since I`m not that excited about convection overnight, think there should be enough insolation tomorrow for highs to again reach the mid 80s. Confidence in lows for Sunday night is lower than normal since convection and cold pools could drop temps cooler than otherwise they would be. Lows are forecast to range from around 60 over north central KS to the mid 60s across the eastern counties. .LONG TERM...(Monday through Saturday) Issued at 328 PM CDT Sat May 23 2020 For Monday a frontal boundary oriented north south is progged to remain over the area as the upper trough slowly begins to cut off. Instability is expected to be lower since there should be less chance for daytime heating due to cloud cover and occasional precip. Then for Tuesday through Friday, the cutoff upper low is progged to remain just south of the forecast area. Chances for showers and thunderstorms remains in the forecast because of this pattern with precip probably setting up in a diurnal pattern each day. There are some indications the deformation zone associated with the closed low will propagate south of the forecast area by Friday with some dryer air working in from the northeast. So there is some hope for dry weather to return by the end of the week. Temps are expected to be rather seasonable given a lack of strong temp advection. If we are able to see some sun, highs could bounce up to near 80. Cloudy conditions with rain may keep highs in the lower 70s. Lows should be in the upper 50s and lower 60s through next week. && .AVIATION...(For the 00Z TAFS through 00Z Sunday evening) Issued at 545 PM CDT Sat May 23 2020 LLWS will develop after 3Z as the low level jet increases and the boundary layer decouples. Expect VFR conds to prevail through at least 18z Sunday with an increasing risk for tsra by late afternoon. At this point we will not mention any precip since it is so far out and focus on LLWS overnight. && .TOP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...Wolters SHORT TERM...Wolters LONG TERM...Wolters AVIATION...Omitt