Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 04/14/21

Area Forecast Discussion
National Weather Service Denver/Boulder CO
730 PM MDT Tue Apr 13 2021 .UPDATE... Issued at 730 PM MDT Tue Apr 13 2021 Model differences are quite extreme in the near-term, both in winds and precipitation. However, higher resolution models are assessing and seeing the northwesterly winds on the west side of the Denver Cyclone positioned just east of DIA, which is effectively helping to downslope out a lot of the metro areas. These strong northwesterly winds, gusting 15 to 30 mph should begin to taper off. Looking at the VAD wind profile, it`s really only the low level winds that are NW, with SE showing up just right around 3000 feet AGL. The high resolution models however, have the northwesterly winds remaining all evening and into the night, but becoming much lighter. This would tend to downslope the metro areas early on when they are stronger, then the SE winds just off the surface may be able to overcome and be able to produce precipitation. Will decrease PoPs early this evening, then have them increase. Still interesting to have the GFS and NAM so much heavier than the RAP and HRRR. Winds are starting to relax near the base of the foothills and radar reflectivities are beginning to fill in a bit, so believe this is the right trend for the forecast. && .SHORT TERM...(This evening through Wednesday) Issued at 250 PM MDT Tue Apr 13 2021 Satellite and radar pictures are indicating convective looking showers developing over the mountains and foothills at this time. Models keep west and southwesterly flow aloft tonight and Wednesday. Concerning the synoptic scale energy; there is upward vertical velocity progged for the CWA tonight and Wednesday. The the lower levels, east to southeasterly boundary layer winds are expected tonight and Wednesday. This flow is actually indicated up to the divide on Wednesday. Moisture is pretty deep tonight for most of the CWA. On Tuesday it is relegated mainly to the lower levels. For pops, will go with "likely"s and better for the mountains tonight, with just "likely"s on Wednesday. For the plains 30-60% will suffice tonight, with 0-30%s on Wednesday. The eastern plains should be dry on Wednesday afternoon. The orographic enhancement is not great for the mountains tonight or Wednesday. As far as snowfall amounts go, the current highlights are adequate for the mountains and northern foothills. Lesser amounts for the adjustments plains with no highlights needed. The cooler temperatures; cooler temperatures than normals, are expected to continue for Wednesday`s readings. .LONG TERM...(Wednesday night through Tuesday) Issued at 244 PM MDT Tue Apr 13 2021 The week will be characterized by cool temperatures and repeated rounds of precipitation. On the plains, highs will generally be in the low 40s to low 50s F and lows will be in the low 20s to mid 30s F. The high country should generally be only about 10 degrees cooler. This will mean persistent snow for the higher elevations and rain or mixed precipitation turning to snow through the evening for most of the lower elevations, often to include the mountain valleys and parks. Light, scattered showers will be ongoing across the area Wednesday night into Thursday, though decreasing between waves. Scattered showers will persist early Thursday and should be increasing again into Thursday night as the upper trough to our west advances over Colorado. Model agreement on the timing and placement of the trough continues to improve, putting it directly over northeast Colorado by Friday morning. Confidence continues to increase in widespread, moderate precipitation Thursday night through Friday. QG forcing for ascent should maximize late Thursday night, with subsidence being replaced by moderate lift of 10 to 20 mb/hr. Models suggest persistent moderate to weak ascent for northeast Colorado through Saturday morning. If the system comes in further south, increased moisture advection and upslope flow would support heavier snowfall across much of the area. At this time, the forecast trend is towards the more northern track however. Forecast snow amounts are now just marginal for a Winter Weather Advisory for the eastern plains Friday morning. Uncertainty remains concerning temperatures and resulting accumulations, especially on pavement and therefore travel impacts. We will continue to monitor forecast snow amounts and probable impacts. Snowfall should gradually diminish again Friday afternoon through Sunday morning, with some precipitation ongoing in the high country, mainly the southern mountains and foothills. The trough seems to stall and increase in positive tilt as another trough approaches from the north in northwest flow aloft early next week, which might just clip northeast Colorado. && .AVIATION...(For the 00Z TAFS through 00Z Wednesday evening) Issued at 730 PM MDT Tue Apr 13 2021 The strong northwesterly winds have been downsloping most of the Front Range urban corridor and out to DIA, increasing ceilings and negating precipitation. High resolution models had this well, and have the NWrlys decreasing over the next few hours, which should allow for the SErlys above to be able to increase upslope flow and thereby lower ceilings and allow precip to fall, allowing ceilings to get into MVFR category. There does seem to be an overall trend for winds to become southeasterly after midnight, which should deepen the moist airmass and let ceilings fall even more into the IFR category. There are discrepancies on how much snow will fall and where, with the GFS and NAM showing more widespread snow through the night, whereas the HRRR and RAP show it hugging closer to the foothills. This may mean we have VIS too low in DEN but closer to right for BJC. Still uncertain how the CIGS and VIS will react at APA with southeasterly winds, since this could downslope slightly from the Palmer Divide. && .BOU WATCHES/WARNINGS/ADVISORIES... Winter Weather Advisory until 6 AM MDT Wednesday for COZ033>035. && $$ UPDATE...Kriederman SHORT TERM...RJK LONG TERM....Direnzo AVIATION.....Kriederman
Area Forecast Discussion
National Weather Service Caribou ME
1102 PM EDT Tue Apr 13 2021 .SYNOPSIS... A ridge of high pressure will persist over the area and slowly weaken through Thursday. Low pressure will approach Thursday night, cross the Gulf of Maine through Friday, then exit across the Maritimes Saturday. High pressure will cross the region Sunday. && .NEAR TERM /THROUGH WEDNESDAY/... 1045 PM Update: Winds had kicked up a bit w/a little surge this evening. 00Z UA showed a 25 kt jetlet around 800mbs which was allowed to mix down to the sfc. High pres ridge will re- establish itself overnight w/winds dropping off. Clear skies and the light winds will lead to radiational cooling. Low lying sites already down in the upper 30s and the continued cooling is expectd overnight. Could be seeing some upper 20s by daybreak across the north and west, especially in the low lying areas. Clouds are trying to work their way back toward the eastern Maine-New Brunswick border. Latest NAM and RAP show some clouds working toward eastern Maine by early morning hrs. Daycrew had this handled well and did not do much adjustment. Previous Discussion... A period of quiet weather will continue for the next couple of days with the ridge of high pressure in place. The biggest forecast challenge for Wednesday remains temperatures for the day. This is highly dependent on whether the band of stratus over New Brunswick makes its way into eastern Maine. Current thinking is that the stratus will fill back in overnight in the Downeast region, but then dissipate. This will keep overnight lows a little warmer for Downeast, but also temper the daytime heating since they will get a later start. Currently planning to keep temps above freezing for Downeast, but in the upper 20s overnight for inland regions, with temps reaching into the 60s Weds afternoon for inland areas and mid to upper 50s for Downeast, making Weds most likely the warmest day of the week. && .SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/... High pressure will cross the region Wednesday night through early Thursday, then begin to exit across the Maritimes later Thursday. At the same time, surface/upper level low pressure will be located across the Great Lakes while another low begins to develop along the Mid-Atlantic coast. Generally expect mostly clear skies across the region Wednesday night through Thursday. The upper low moves east Thursday night, while the coastal low lifts to southern New England. Expect increasing clouds across the region Thursday night, particularly Downeast. The surface/upper lows move to the Gulf of Maine Friday. Expect mostly cloudy skies along with increasing rain chances across Downeast areas Friday, with increasing clouds across northern areas. Expect above normal level temperatures Thursday. Slightly above normal level temperatures are expected across northern areas Friday, with slightly below normal level temperatures Downeast with more extensive cloud cover and developing rain. && .LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/... The surface/upper lows cross the Gulf of Maine Friday night through early Saturday, then exit southeast of Nova Scotia later Saturday. At the same time, high pressure will remain ridged north of Maine. Uncertainty still exists regarding the track of the surface/upper lows. The greater precipitation chances will occur Downeast, with lesser precipitation chances northward across the remainder of the forecast area. A more northerly low track would increase precipitation amounts across Downeast areas, with increased precipitation chances across northern areas. A more southerly low track would diminish precipitation amounts Downeast and limit precipitation chances across northern areas. Based on critical thicknesses, the vicinity of the cold pool aloft with the upper low and favorable overnight diurnal timing, expect precipitation will mix with and change to snow across the region Friday night which should persist early Saturday. Accumulating snow is expected across much of the region Friday night through early Saturday. However, amounts will be dependent on how rapidly the transition to snow occurs and the eventual tracks of the surface/upper lows. Precipitation will then taper to rain showers Saturday. A series of difficult to time upper level disturbances and surface trofs are possible Sunday through Tuesday. Generally expect partly/mostly cloudy skies Sunday through Tuesday. Have kept shower chances at slight chance levels due to the uncertainty with timing. Expect near normal level temperatures Saturday. Above normal level temperatures are expected Sunday through Tuesday. && .AVIATION /03Z WEDNESDAY THROUGH SUNDAY/... NEAR TERM: VFR expected through Weds. Some chance of MVFR in cigs late tonight/Weds morning for CAR/PQI/HUL. Gusty winds less than 25kts expected to calm overnight. SHORT TERM: Wednesday night through Thursday night...Generally VFR, though MVFR possible later Thursday night. Light winds Wednesday night. East/southeast wind 10 to 15 knots Thursday, then east/northeast 10 to 15 knots Thursday night. Friday...VFR/MVFR. Rain late mostly Downeast. East/northeast wind 10 to 20 knots with gusts up to 25 knots. Friday night...MVFR/IFR, occasional LIFR. Rain mixing with and changing to snow. North/northeast wind 10 to 20 knots with gusts up to 25 knots. Saturday...MVFR/IFR, occasional LIFR, early. VFR/MVFR late. Snow tapering to rain showers. North/northeast wind 10 to 20 knots with gusts up to 25 knots. Saturday night through Sunday...VFR/MVFR. North/northeast wind around 10 knots Saturday night. Light winds Sunday. && .MARINE... NEAR TERM: SCA conditions will continue in the outer coastal waters overnight. Winds will drop below 25kt from S to N by the early morning hours, but seas will remain above 4 ft through tomorrow morning. SHORT TERM: Conditions below small craft advisory levels Wednesday night/Thursday. Small craft advisory conditions expected Thursday night. Gale force wind gusts possible Friday into early Friday night. Visibilities lowering in rain Friday. && .CAR WATCHES/WARNINGS/ADVISORIES... ME...None. MARINE...Small Craft Advisory until 8 AM EDT Wednesday for ANZ050-051. && $$ Near Term...Hewitt
Area Forecast Discussion
National Weather Service Quad Cities IA IL
832 PM CDT Tue Apr 13 2021 .UPDATE... Issued at 830 PM CDT Tue Apr 13 2021 Have expanded the Frost Advisory to include the I-80 corridor. Latest satellite trends show the stratus into northern Iowa moving more latitudinal than longitudinal, and would support some of the recent guidance in keeping the I-80 corridor, which has some susceptible vegetation, largely absent of this thermally impactful cloudiness. Some cirrus will be present, but satellite shows this to be rather thin and should be limited in impacts to temperatures. With 850 mb temperatures progged back down to around -5C to -6C tomorrow morning, anticipate lows near to a bit below those from this morning in most areas and around 30-36F. Far northern sections, especially in eastern Iowa, lows are a bit tricky as the stratus may eventually work southward and offer periodic bouts of cloudiness. Thus, it looks like there is the potential to be a bit warmer than forecast into portions of northeast Iowa. && .SYNOPSIS... Issued at 244 PM CDT Tue Apr 13 2021 Another great day was unfolding across all of eastern Iowa, northwest Illinois and far northeast Missouri, with the area under influence from high pressure ridging extending from the central Great Plains into the Ohio River Valley. Skies featured a mix of sun and clouds, with somewhat cool temperatures atypical for mid-April. Values as of 2 PM ranged from 47 in Dubuque, to 57 in Keokuk. && .SHORT TERM...(This Evening through Wednesday) ISSUED AT 244 PM CDT Tue Apr 13 2021 Key Messages: 1) Patchy to areas of frost tonight, with impacts likely mainly south of I-80. 2) A chance for PM sprinkles Wednesday, but most will remain dry. Cool temperatures continue. High pressure will remain in control of our weather for through Wednesday, meaning quiet weather with mainly dry condtions are expected. The only exception will areas of eastern Iowa and northwest Illinois mainly north of I-80 Wednesday afternoon, where there will be a chance of sprinkles. Several CAMs including the NAMnest and HRRR are on board with this idea as an area of CVA rotates around the southern portion of a 500 hPa low centered over the Great Lakes. These will be scattered in nature, with much of likely remaining dry through the day. The more pressing concern will be the threat of frost tonight, which looks likely with light winds, clear skies and a cool air mass in place across parts of the area. After coordinating with surrounding offices, went ahead and issued a frost advisory for counties along and south of Hwy 34 in southeast Iowa, west central Illinois and far northeast Missouri. This area is most susceptible across the CWA with regards to vegetation. Temperatures are expected to fall into the low to mid 30s here. Elsewhere, temperatures will be cold with values dropping to near 30 along the Hwy 20 corridor. With no susceptible vegetation here did not go ahead with frost/freeze headlines. Highs tomorrow will continue to be cool with values in the upper 40s/low 50s. .LONG TERM...(Wednesday Night through Tuesday) ISSUED AT 244 PM CDT Tue Apr 13 2021 Key Messages: 1) Below normal temperatures continue. 2) Mainly dry through the weekend; precipitation chances increase next week. 3) Potential for frost again Wednesday Night/Thursday Morning. Wednesday night and Thursday morning will once again be monitored for frost/freeze potential as another night of cold temperatures is expected. While temperatures are forecast to not be as cold as tonight, values in the low 30s will be more widespread. Will monitor for potential for more headlines tomorrow. Otherwise, most of the long term period will feature mainly dry conditions and continued cool temperatures with the dominant flow pattern expected to remain out of the northwest. Daily highs in the 50s to near 60 are expected, with overnight lows in the 30s to low 40s. Chances for precipitation are mainly favored Friday night and Saturday as a weak shortwave passes across the area to the south. Models are in disagreement of intensity, with the GFS suggesting more of a moisture draw, stronger lift and thus a higher QPF for our southeast Iowa, west central Illinois and northeast Missouri counties. However, this looks to be the outlier of guidance, so will play more on the conservative end with just a slight chance to chance of POPs. This is favored over our southeast Iowa, west central Illinois and northeast Missouri counties. There is agreement that a cold front approaching the area will be the driver for our next chance of precipitation, which looks to be favored next Monday/Monday night. NBM has introduced slight chance POPs with this run, and I think that`s a good starting point considering we have plenty of time for things to get more refined in the guidance. && .AVIATION...(For the 00Z TAFS through 00Z Wednesday Evening) ISSUED AT 547 PM CDT Tue Apr 13 2021 Predominantly VFR conditions expected during the period. Stratus will continue decreasing with sunset leading to mainly clear skies tonight, with gusty WNW winds diminishing to below 10 kts. On Wednesday, stratus will redevelop with surface heating in the presence of cyclonic flow/cold advection. CIGs may initially range from lower VFR to some MVFR, but with mixing should evolve into solidly VFR. WNW winds also look to increase on Wednesday at or above 10 kts and gust up to 20 kts at times by late morning through the afternoon. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...Frost Advisory from 1 AM to 8 AM CDT Wednesday for Cedar-Des Moines-Henry IA-Iowa-Jefferson-Johnson-Keokuk-Lee-Louisa- Muscatine-Scott-Van Buren-Washington. IL...Frost Advisory from 1 AM to 8 AM CDT Wednesday for Bureau- Hancock-Henderson-Henry IL-McDonough-Mercer-Putnam-Rock Island-Warren. MO...Frost Advisory from 1 AM to 8 AM CDT Wednesday for Clark- Scotland. && $$ UPDATE...McClure SYNOPSIS...Speck SHORT TERM...Speck LONG TERM...Speck AVIATION...McClure
National Weather Service Jackson KY
1141 PM EDT Tue Apr 13 2021 .UPDATE... Issued at 1141 PM EDT TUE APR 13 2021 Skies have partially cleared across portions of the Cumberland Valley, with scattered to broken mid-level clouds hanging on across the rest of the area. A few sprinkles are still showing up on radar across southern Kentucky. The latest higher resolution model guidance suggests little in the way of shower activity until closer towards dawn near the I-64 corridor; however, much of the guidance does not have the current activity captured that well. Have therefore kept in a few sprinkles through the night, with an uptick in PoPs and more in the way of isolated shower activity towards the Bluegrass closer to daybreak. Current temperatures range from the lower to middle 50s in the cooler spots, to around 60 on ridges. Made a few adjustments to the lows, mainly to allow up to a several degree split, given the cloud breaks from time to time. Updates have been sent. UPDATE Issued at 824 PM EDT TUE APR 13 2021 A few showers have popped up south of the Hal Rogers Parkway, where some modest isentropic lift is occurring, according to the latest RAP data. This forcing should subside in the next hour or so. Accordingly, have included some slight chances for our south early this evening. The rest of the forecast remains on track, and have mainly freshened up the hourly temperatures through this evening. Updates have been sent. && .SHORT TERM...(This evening through Wednesday night) Issued at 517 PM EDT TUE APR 13 2021 Short term challenges center around a couple of minor shortwave impulses moving through a zonal flow pattern aloft. At the surface there are a couple of surface troughs spinning around the southern side of low pressure centered over Lake Superior. There is also a stationary frontal zone to our south across the Tennessee Valley. Models have not been consistent with sensible weather, and in particular PoPs. Light showers are expected to develop late tonight as the first of the two troughs out to our northwest drops southeast into the Commonwealth. Wind profiles (H850 winds) do not provide much support for shower activity until closer to dawn Wednesday. With inconsistencies seen in previous runs, decided to stick closer to low chance PoP across the north closer to the boundary, and only slight chance PoPs across the south. Ramped PoPs up for Wednesday as the surface wave of low pressure tracking through Tennessee and Southern Appalachia interacts with the surface boundary dropping southeast across eastern Kentucky. This second feature, or wave of low pressure will provide the best opportunity for rain to the area. With the exception of NBM, there is little if any chance for any thunder based on guidance. The NBM brings a slight chance of thunder across the south. With all the uncertainties and relatively lower confidence in model guidance, decided to stick with previous forecasts, leaving any mention of thunder out of the forecast. However, will mention this to upcoming shifts for a closer look. Temperatures will run just below normal for this time of year with afternoon highs Tuesday in the lower 60s and overnight lows dipping to around 50 tonight and to around 40 tomorrow night. Can not totally rule out a little patchy frost in our western valleys late Wednesday night into early Thursday as temperatures drop into the mid 30s. .LONG TERM...(Thursday through Tuesday) Issued at 332 PM EDT TUE APR 13 2021 Eastern Kentucky begins the period sandwiched between a deep low across the Great Lakes and embedded short waves across the Southern Tennessee Valley and deep south. A cold front will be departing eastward as a surface high meanders east across the Central Plains and into Western Kentucky. Flow will then shift out of the west/northwest. This should allow for continued clearing Thursday afternoon and evening. Frost development continues to look best Thursday night into Friday morning as there will be clearer skies and calmer winds, and therefore, better ridge/valley splits. This, again, will depend on how much sky clearing is seen into Thursday night. By Friday, high pressure will be positioned along the Mid- Atlantic, allowing for an uptick in highs when compared to Thursday, but still remaining below average. Through the weekend and early next week, embedded shortwaves will bring unsettled activity. These features do promote the opportunity for moisture, but it remains limited across the CWA. There is also quite a bit of uncertainty in regards to timing and QPF, with the GFS being the most aggressive. Long term guidance suggests an area of low pressure developing and evolving eastward from southern Canada late in the period, but for now, have stayed with the blend given the large uncertainties. Overall, temperatures remain below normal through the period with highs ranging from the low to mid 60s and lows in the low to mid 40s. && .AVIATION...(For the 00Z TAFS through 00Z Wednesday evening) ISSUED AT 824 PM EDT TUE APR 13 2021 Clouds will gradually thicken and lower tonight, with a few showers threatening, mainly after 06z. Better rain chances will move in during the day on Wednesday, as area of low pressure tracks across the southern Appalachians. Ceilings will dip down to the MVFR/IFR as the more sustained activity occurs into Wednesday afternoon. Improvement back to VFR will move in across the I-64 corridor, including KSYM late in the period. Winds will be light and variable tonight, before increasing to 5 to 8 kts, generally out of the north northwest Wednesday morning. Winds will then lighten up once again later in the day. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...GEOGERIAN SHORT TERM...RAY LONG TERM...BB AVIATION...GEOGERIAN
Area Forecast Discussion
National Weather Service Nashville TN
815 PM CDT Tue Apr 13 2021 .UPDATE... FOR EVENING DISCUSSION. && .DISCUSSION... Radar this evening shows widely scattered showers across the southeast two-thirds of the cwa. This activity is occurring in a WAA regime above a weak cold front stalled across our southeast counties. These evening showers should continue moving eastward out of the area over the next couple hours, and have added a slight chance pop for the evening in line with the HRRR and CONSShort models. Little activity is expected most of the night, but additional showers will spread into our northwest counties toward sunrise with pops increasing from northwest to southeast. Made some minor adjustments to pops and sky cover for the overnight hours but nothing major. Although current temperatures across the area are in the mid to upper 60s, CAA behind the front will drop temperatures down into the low to mid 50s overnight. Highs tomorrow will be several degrees cooler over our northwest versus our southeast due to the stalled frontal boundary. Light rain will spread across the entire area during the day but most precip will be out of here by evening, with total rainfall amounts ranging from a tenth up to a third of an inch. && .AVIATION... 00Z TAF DISCUSSION. Despite some VCSH at CSV, all terminals are currently at VFR. Cigs and vis will begin to decrease tomorrow morning with some heavier showers moving through the area. Expecting MVFR to IFR conditions beginning with CKV around 15Z and remaining terminals between 17Z and 18Z. Northerly winds remain through the TAF period. && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ DISCUSSION......Shamburger AVIATION........Adcock
Area Forecast Discussion
National Weather Service Springfield MO
640 PM CDT Tue Apr 13 2021 .SHORT TERM...(This evening through Wednesday) Issued at 108 PM CDT Tue Apr 13 2021 Cloud cover continues to gradually break up this afternoon as the disturbance that produced rain last night and early this morning exits the region to the east. A weak surface front was located over southern Arkansas with cooler north winds over the region holding temperatures down in the upper 60s to lower 60s. We`re just starting to see some increasing cloud cover over southwest OK and the TX Panhandle as another upper level disturbance moves over the central and southern Plains. The disturbance will interact with lower level convergence along an elevated front at around 850 mb which lines up just south but parallel to I-44 to produce mainly scattered showers this evening and overnight over southern MO and southeast Kansas. The HRRR is forecasting the heaviest rainfall to occur from 2 AM to 6 AM. Not seeing much instability on Bufkit forecast soundings but some steeper mid- level lapse rates may be adequate to get a few storms, mainly south of Highway 60. Most of the showers are expected to be east of the forecast area by late morning to early afternoon Wednesday with afternoon temperatures similar to today, topping out in the 60s. .LONG TERM...(Wednesday Night through Tuesday) Issued at 306 PM CDT Tue Apr 13 2021 There is still potential for frost early Thursday morning over central Missouri and higher elevations on the Ozark Plateau, where little to no cloud cover is expected. Further south, there may be enough cloud cover with another disturbance moving from the southern Plains into Arkansas. The National Blend of Models temperature output shows very little spread in temperature forecast for the next 4-5 days so confidence remains high for below normal temperatures through the forecast period. Another chance for rain still looks likely for Friday and Saturday as a surface low deepening over west Texas draws Gulf Moisture northward into the our region. While the main surface front remains south of the area, decent lift with the upper low should generate a fairly widespread 0.5 inch to inch of rain over the region. Not seeing too much in the way of instability over our area, so thunderstorms have been kept out of the forecast for now. High pressure builds in behind the passing upper low and drops temperatures even more for the weekend with highs only expected to rise into the 50s. Thereafter expect mainly dry conditions early next week with only a slight warmup into the 60s by Monday. Could see an additional cool down in the middle of next week with a cold front passage Tuesday or Wednesday. && .AVIATION...(For the 00Z TAFS through 00Z Wednesday evening) Issued at 625 PM CDT Tue Apr 13 2021 Middle to high cloud cover will increase through this evening as showers spread into the Ozarks from Oklahoma. Ceilings will lower but remain VFR for the Joplin and Springfield aerodromes but Branson can expect MVFR ceilings. Branson will be more impacted as the it will be closer to the main area of rain. Flight conditions will begin to improve by midday Wednesday as the rain shifts east of the region. && .SGF WATCHES/WARNINGS/ADVISORIES... MO...NONE. KS...NONE. && $$ SHORT TERM...Terry LONG TERM...Terry AVIATION...Hatch
Area Forecast Discussion
National Weather Service Shreveport LA
909 PM CDT Tue Apr 13 2021 .UPDATE... Updated forecast was minor this evening, pertaining to the returning warm front across our region and its effects on pops for the remainder of the night. Chasing a leftward moving supercell along a retreating warm front this evening across portions of NE TX with several reports of severe hail along its path before it finally dissipated across Eastern Harrison County and Southwest Caddo Parish. We are still dealing with some widely scattered convection across portions of NE TX located along an instability axis which extends from SE TX into extreme NW LA and SW AR. Latest HRRR and 00z NAM output suggests that our western third will continue to see the possibility of renewed convection in association with this instability axis and the northwestward moving warm front before broad scale lift increases dramatically late tonight and therefore storm coverage does as well areawide. Perturbation in developing southwest flow aloft coming out of the TX Hill Country and a developing 30-40kt low level jet will generate the necessary upward and isentropic forcing for the development of scattered to numerous showers and thunderstorms late tonight through the first half of Wednesday. While the instability axis should weaken overnight, mid level lapse rates are sufficient enough for at least some large hail overnight, mainly across our southwest half, depicted best by SPC`s maintaining a Slight Risk across our region. Only change was to reorganize pops for the remainder of the evening more towards the west with likely pops areawide as we approach sunrise Wed Morning. Update will be out shortly...13. && .PREV DISCUSSION... /issued 523 PM CDT Tue Apr 13 2021/ AVIATION... A nearly stationary frontal boundary across our airspace and a very unstable environment near a LFK, to SHV to ELD line will result in the development of widely scattered thunderstorms this evening that should begin shifting and/or developing to the north and west as the boundary lifts north and west through the evening hours. Forcing will be subtle but enough from the west to help initiate more in the way of scattered to numerous showers and thunderstorms after midnight and especially during the morning hours on Wednesday across much of our airspace. Winds will remain mostly from the E or NE with speeds under 10kts through the night except for convectively induced winds which could be much stronger. Look for ceilings to gradually become MVFR overnight and eventually, IFR with prevailing TSRA through much of the morning hours on Wed before the precipitation exits the region to the east during the afternoon hours on Wed. While the convection should end during the afternoon, look for post frontal ceilings to remain mostly IFR with MVFR VSBYS in the wake of the convection to prevail through the afternoon hours as well. 13 && .PRELIMINARY POINT TEMPS/POPS... SHV 60 69 53 71 / 70 60 60 20 MLU 61 68 51 70 / 70 80 50 20 DEQ 54 67 49 70 / 70 50 30 10 TXK 57 64 50 69 / 70 50 40 10 ELD 54 64 48 70 / 70 60 40 10 TYR 62 69 52 70 / 70 40 60 20 GGG 60 69 52 70 / 70 50 60 20 LFK 66 73 55 72 / 70 50 70 30 && .SHV WATCHES/WARNINGS/ADVISORIES... AR...None. LA...None. OK...None. TX...None. && $$ 13/13