Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 05/15/22


AREA FORECAST DISCUSSION
National Weather Service Albany NY
1040 PM EDT Sat May 14 2022 .SYNOPSIS... A warm and humid air mass will continue through Monday. An upper level disturbance will bring scattered showers overnight. Additional afternoon and evening showers and thunderstorms are expected Sunday. On Monday, a strong cold front could bring strong to severe thunderstorms during the afternoon and evening hours. Cooler and less humid conditions take place Tuesday behind the passage of the cold front. && .NEAR TERM /UNTIL 6 AM SUNDAY MORNING/... .UPDATE as of 1040 pm EDT...Pop-up convection has diminished and moved north and west of the ALY forecast area. Showers and the rain shield associated with the short-wave moving northward across northern NJ and the lower Hudson River Valley on the GOES-16 water vapor imagery continues to break up moving into the mid-Hudson Valley and southwest New England. The showers have dried up a bit, but the latest 3-km HRRR has showers breaking out over the Capital Region, eastern Catskills, mid Hudson River Valley, Lake George/Glens Falls area and southern VT between 03Z-06Z. We tried to the trend the PoPs to high chance and low likely values shortly before and just after 06Z. The latest SPC RAP Mesoanalysis indicates PWATs have risen to 1.2-1.4" and the 00Z KALB has value risen to 1.36". The MUCAPE values have diminished to less than 500 J/kg, so we removed the slight to low chance of thunderstorms from the overnight forecast. Moisture has struggled to moved northward, and possibly some low to mid level dry air and weak upper-level dynamics has limited the northward push. We`ll continue to monitor the short-wave and showers. Humid conditions persist overnight. Lows will be in the mid 50s to lower/mid 60s. Previous near term...Isolated showers and thunderstorms that popped up over the higher terrain and near differential heating boundaries are starting to diminish with a few lingering cells over the southern Adirondacks, southern Greens, and western Mohawk Valley. Highest rain tally was 0.81" at Old Forge We kept a slight chance of thunderstorms a few more hours as these "pulse-type" storms should diminish with the loss of the diurnal heating. Attention shifts to showers or stratiform rain region approaching from northeast PA, the lower Hudson River Valley and Long Island with the short-wave associated with the upper low over the mid Atlantic Region. Showers with a rumble of thunder are possible for early this evening. Some trending and retooling of the PoPs was done based on the regional radar and the latest 3-km HRRR and NAM. Temps will be mild and lows tonight expected in the mid 50s to lower/mid 60s. && .SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY NIGHT/... Slight Risk for Severe Thunderstorms Monday across all of eastern New York and adjacent western New England... Warm and humid conditions continue on Sunday. Differential surface- based diurnal heating couple with a pre-frontal trough ahead of a slowing/stalling cold front that will serve as a lifting mechanism will help to trigger some scattered showers and thunderstorms during the afternoon hours. SBCAPE/MUCAPE values increase to 500-1500 J/kg primarily along and west of the Hudson River Valley Sunday afternoon/evening with lesser amounts east. Despite the CAPE values, other instability parameters overall are not too great and shear values are very weak with hardly any flow aloft. That said, there`s low confidence that storms will reach severe limits. However, some storms could become strong with heavy downpours and gusty winds. Daytime highs are expected to reach the upper 70s to near 80F. Sunday night will be mild and muggy with overnight lows holding in the lower 60s with similar dewpoint values. Dynamics and synoptic setup lends to greater confidence in the potential for severe weather on Monday. During the day on Monday, the forecast area will remain in the warm sector of a storm system centered to our north. Aloft, a formidable neutral to negatively- tilted trough will be approaching from the Great Lakes Region. At the surface, a cold front will be approaching from the west. Ahead of this cold front, south-southwest flow will allow for highs to reach the upper 70s to lower 80s with dewpoints remaining in the lower 60s. Showalter values suggest a moderately unstable atmosphere with values between 0 to -2. Kinematics will be stronger with 0-6km bulk shear values expected to increase between 35-50 kts. SBCAPE/MUCAPE values will be between 500-2000 J/kg. That said, strong to severe thunderstorms are possible Monday afternoon/evening with the primary severe threat being damaging wind gusts. The entire forecast area remains under a Slight Risk for severe weather on Monday. Behind the passage of the cold front, cooler and drier air will advect into the region. Overnight low temperatures are forecast to be in the lower 50s along the river valleys (40s higher elevations). && .LONG TERM /TUESDAY THROUGH SATURDAY/... Upper-level low will be positioned north of our region on Tuesday as we will be in a west to northwesterly cold air advection regime. Enough lingering moisture could lead to a few showers during the day, mainly for areas north and west of Albany. Otherwise, expect a partly to mostly cloudy, breezy, cooler and less humid day with highs ranging from the lower to mid-50s across the Adirondacks to the upper 60s/lower 70s in portions of the Hudson Valley into Litchfield County, CT. Wind gusts could reach or exceed 30 mph in some places during the afternoon hours. Flow becomes more zonal Wednesday and Thursday with high pressure nearby which should yield mainly dry conditions. A weak shortwave and disturbance will pass across the mid-Atlantic late Wednesday through Thursday but most if not all activity looks to stay to our south. Temperatures will run fairly close to normal on these days with Thursday a bit warmer than Wednesday. Signals point to upper-level ridging building into our region along with a low-level southerly flow which should result in a warming trend as well as an increase in dewpoint temperatures back to the 50s to perhaps some lower 60s. We trended high temperatures both Friday and Saturday up slightly from NBM guidance due to this signal. Highs by Saturday may return to the upper 70s to upper 80s. There is not enough confidence to forecast any lower 90s just yet. Guidance is a bit uncertain whether there is enough of a trigger for showers and thunderstorms on these days, however. For now, ran with NBM pops which introduced some slight chance to low chance pops. && .AVIATION /03Z SUNDAY THROUGH THURSDAY/... An upper level disturbance will bring some showers and few thunderstorms across the region tonight. The showers may evolve more into a stratiform region of rainfall south and east of the Capital Region. Showers will diminish during the morning hours with isolated to scattered showers in the afternoon with a prefrontal disturbance. Moisture from the south is slowly moving towards the mid Hudson Valley and KPOU. We had to slow down the trend to bring the rainfall in there. VFR conditions will lower to MVFR levels with the showers and a TEMPO group was used 00Z-03Z/SUN. Expect conditions to lower to low MVFR/IFR levels overnight in terms of cigs and vsbys in the showers, which may be more of a stratiform rain region. Further northward, expect showers to overspread KALB/KPSF between 03Z-07Z/SUN with VFR conditions lowering to MVFR. KGFL may have some showers move in 04-06Z/SUN and we used TEMPOs to address arrival. After 06Z...expect KGFL/KALB/KPSF low MVFR cigs 1-2.0 KFT AGL cigs to lower to IFR levels between 08Z-12Z/SUN in the deeper moisture and muggy air mass. Showers/rain diminishes shortly before 12Z/SUN with continuing IFR/MVFR cigs. IFR cigs may linger the longest at KPSF until close to 16Z/SUN. Should see conditions improve to VFR levels by the early afternoon at all the TAF sites. Additional showers and possibly isold-sct t-storms are possible in the afternoon. We did include PROB30 groups after 18Z or 20Z/SUN, and thunder may be added with later TAF issuances if confidence and coverage of possible thunderstorms increases. South/southeast winds 5-10 kts will become light and variable at 3 kts or less overnight. The winds will be south/southwest at 10 kts or less in the late morning into the afternoon. Outlook... Sunday Night: Moderate Operational Impact. Chance of SHRA...TSRA. Monday: High Operational Impact. Definite SHRA...TSRA. Monday Night: Moderate Operational Impact. Chance of SHRA. Tuesday: Moderate Operational Impact. Breezy. Chance of SHRA. Tuesday Night: No Operational Impact. NO SIG WX. Wednesday: Low Operational Impact. Breezy. NO SIG WX. Wednesday Night: No Operational Impact. NO SIG WX. Thursday: No Operational Impact. NO SIG WX. && .FIRE WEATHER... No fire weather issues anticipated over the next few days. A warm and humid air mass will continue through Monday. Isolated showers and a few thunderstorms this afternoon will give way to more widespread showers tonight. Additional afternoon and evening showers and thunderstorms are expected Sunday. On Monday, a strong cold front could bring strong to severe thunderstorms during the afternoon and evening hours. Cooler and less humid conditions take place Tuesday behind the passage of the cold front. Tonight, relative humidity values will max out between 85-100%. On Sunday, minimum relative humidity values will range between 50-70%. Sunday night, maximum relative humidity values will range between 90- 100%. On Monday, minimum relative humidity values will range between 40-60 %. Monday night, maximum relative humidity values will range between 75-100%. For Tuesday, minimum relative humidity values will range between 35-60%. Tuesday night, maximum relative humidity values will range between 70-95%. Tonight, winds are expected to become light and variable. On Sunday, winds will be out of the south-southwest at 5-10 mph. Sunday night, winds will become light and variable to calm. On Monday, winds will be out of the south-southwest at 10-15 mph with gusts as high as 25 mph. Monday night, winds will have shifted out of the west behind the cold frontal passage 5-15 mph with gusts 20-25 mph. On Tuesday, west-northwest winds will continue at magnitudes between 10-20 mph with gusts as high as 30 mph. && .HYDROLOGY... There will be isolated to scattered showers and thunderstorms this afternoon and evening, with widespread showers expected tonight. Additional showers and thunderstorms are expected Sunday afternoon and evening, and again Monday afternoon and evening. Given relatively dry soil conditions and low streamflows, no significant hydrologic response is expected on area rivers/streams through Monday. However, localized ponding of water in urban or poor drainage areas is possible from any heavy downpours that occur. For details on specific area rivers and lakes, including observed and forecast river stages and lake elevations, please visit the Advanced Hydrologic Prediction Service /AHPS/ graphs on our website. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. MA...None. VT...None. && $$ SYNOPSIS...Evbuoma/Wasula NEAR TERM...Evbuoma/Wasula SHORT TERM...Evbuoma LONG TERM...Rathbun AVIATION...Wasula FIRE WEATHER...Evbuoma/KL HYDROLOGY...Evbuoma/KL
Area Forecast Discussion
National Weather Service Quad Cities IA IL
656 PM CDT Sat May 14 2022 ...00Z AVIATION UPDATE... .SYNOPSIS... Issued at 237 PM CDT Sat May 14 2022 A beautiful day was felt throughout the area today, as high pressure overhead gave us clear skies and light winds. Temperatures are still well above average, but much more tolerable without the humidity. Currently, much of the area is sitting in the mid 80s. Dry conditions are expected up until the evening, when we get our first chance for showers and storms in the northwest. Better chances for more widespread rainfall late tonight and tomorrow. Active pattern continues through through the long term period, so we aren`t off the hook yet. && .SHORT TERM...(This Evening through Sunday) ISSUED AT 237 PM CDT Sat May 14 2022 High pressure slowly slides off to our east, as a weak wave approaches the area. Most of the night, dry conditions are expected. There are some slight chances along the approaching cold front early this evening in our northwest. Short term guidance is showing a weak line of showers and maybe some thunder, but these will be quick to die off thanks to a dry airmass out ahead of them. Currently, this line is showing some development out along the IA/NE border, which is a few hours earlier than indicated in guidance, but is also struggling to maintain. Will have to watch though, as this may lead to some timing differences. In all, severe threat is low in the area due of lack of instability and low shear. Thus, garden variety showers and storms with this first round, if the dry air doesn`t succeed. Once again, we are looking at a cool night throughout the area. This will feel much more comfortable than the overnight temperatures in the 70s last week, with much of the area sitting in the mid 50s. Late tonight and into tomorrow morning, the stronger upper forcing pushes in with the incoming wave. This, with some moderate frontogenesis near the surface, will allow for more shower and storm development. The bulk of the forcing will be focused in areas along and south of Interstate 80. Thus, highest QPF and PoPs are also collocated in this area. Areas north of the interstate still have a chance to see showers and storms, but lesser coverage and overall QPF is expected in these areas. Again, we aren`t expecting much of anything on the severe side, as this is looking to mainly be light to moderate rain showers with embedded thunder. Temperatures tomorrow aren`t expected to increase much, due to cloud cover and rain showers from the passing system. It will feel much cooler than it has been lately, with most sitting in the upper 60s to low 70s. I am sure some will enjoy these temperatures, compared to the 90s and high humidity of last week! .LONG TERM...(Sunday Night through Saturday) ISSUED AT 237 PM CDT Sat May 14 2022 Key Messages: 1. Chances for pops in the extended remain. 2. Temperatures will start out around normal then increase to hot and humid again to end the week. 3. While pattern is active, no strong wave/low is expected, therefore overall forecast skill on details is low. Discussion: Surface high pressure on the heels of strong shrtwv will move into the area after 00z Monday. Some lingering showers could be found across central IL, otherwise expect dry conditions. NW flow lasts through Tuesday before zonal flow and a wave move across the area. This wave moves over a stalled boundary just south of the area and leads to chances of pops Tuesday night into Wednesday across the area. The flow turns SW Thursday as the boundary south of the area is pulled north as a warm front leading to heat and humidity for the day. A progressive wave starts to induce cyclogenesis across the central CONUS for the weekend leading to showers and storms Friday night into Saturday. An even stronger shot of cold air is expected next weekend behind the system Friday. Chances for storms look best at the end of the week as better moisture and MUCAPE return to the area. With the model uncertainty in timing of pops, have decided to go schc thunder through period to account for this fact. While CAPEs increase late in the period, shear is weak. Therefore updraft organization looks poor and thus widespread strong to severe storms looks unlikely. If the warm front is further south or the wave moves south, this could change that. && .AVIATION...(For the 00Z TAFS through 00Z Sunday Evening) ISSUED AT 651 PM CDT Sat May 14 2022 Shower and storm chances will arrive by late evening and remain through Sunday focused initially with a cold frontal passage and followed by an upper level disturbance. The latter could result in the likelihood of precip Sunday for the terminals, but seeing enough disagreement with guidance on location of greatest potential to hold off mention with this TAF package. As for the front, some development is being hinted at by HRRR and other CAMs tonight, but confidence too low within the 9 hr window for a TEMPO or prevailing mention. Will continue to monitor radar/obs and amend if needed. Outside of any precipitation, expect VFR conditions. Winds will be light and variable or SW, turning NNW later tonight into Sunday AM in wake of the front. CID/DBQ could see a brief bout of NW wind gusts this evening with decaying outflow from showers in central Iowa. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...NONE. IL...NONE. MO...NONE. && $$ SYNOPSIS...Gibbs SHORT TERM...Gibbs LONG TERM...Gunkel AVIATION...McClure
Area Forecast Discussion
National Weather Service Goodland KS
850 PM MDT Sat May 14 2022 .UPDATE... Issued at 849 PM MDT Sat May 14 2022 Based on current radar coverage, have added in a mention of sprinkles to northern portions of the cwa for the next few hours. && .SHORT TERM...(This evening through Sunday) Issued at 104 PM MDT Sat May 14 2022 19z Water vapor imagery and RAP analysis indicate broad westerly flow aloft amidst a rather zonal pattern across the Western half of the country. Embedded short wave trough apparent on dynamic tropopause moving into Washington state. At the surface a frontal zone was stalled along a Benkelman to Tribune line, extending east across southern Nebraska. Main concern for the near term will be thunderstorm potential today, followed by period of stronger winds Sunday morning. Aforementioned frontal zone will likely represent the western and northern periphery of storm potential through the afternoon and early evening as much drier/more stable air is in place on other side of front. To the east of front, weakly capped and fairly unstable airmass in place with 500-2000 j/kg of CAPE across area. Deep layer shear around 40 kts should be sufficient for storm organization, especially given the large curved hodographs expected. While environment looks good for a few large hail producing storms, the lack of strong forcing may inhibit coverage across our area. Right now threat is conditional on storms initiating and moving into more unstable area, if storms can get going there likely will be a few severe ones. Otherwise storms should move east out of the area in the early evening. There could be a second round of elevated storms after midnight east of a Trenton to Hill City line, along persistent area of strong WAA ahead of next system. Lots of questions around whether or not parcels will be saturated/instability realized that keep confidence pretty low, but worth keeping an eye on. Short wave trough to the north will force cold front across area after 09z. Pressure rises as well as point soundings indicate potential for winds jumping up to around 30 mph with higher gusts for a few hours Sunday morning. The stronger winds will relax through the day, but expect winds in the 15 to 20 mph range to linger along KS/CO state line. .LONG TERM...(Monday through Saturday) Issued at 1257 PM MDT Sat May 14 2022 For the long term period, warm temperatures are forecasted for the majority of the period with Highs in the 80`s and 90`s. However, a few systems are forecasted to move through keeping the area from reaching even higher temperatures and bringing some precipitation chances to the area. The end of the week and into the weekend could see much cooler temperatures. For the beginning of the week, the 500mb pattern is mainly a ridge that spreads across most of the CONUS. However, within the ridge, shortwaves are forecasted to move through the flow and bring an unsettled weather pattern to the Tri-State area. Monday, temperatures are forecasted to warm into the 90`s while an area of surface low pressure develops along the Front Range. This will pull moisture up from the south into the area and help increase chances for storms during the evening hours. The better chances are currently forecasted to be east of Highway 83 as the surface low moves into the CWA during the late afternoon hours. Severe storms could be possible depending on how much moisture is advected and how far east the surface low moves during the afternoon. Tuesday and Wednesday are forecasted to be slightly cooler as the surface low moves slowly off to the south while a bit of higher pressure builds in from the north. Conditions are forecasted to be relatively dry though an isolated storm or couple of storms could be possible, mainly on Tuesday when the surface low is forecasted to still be near the area. Deterministic guidance also continues to show small disturbances in the flow aloft that could contribute to the isolated development. Going into the later part of the week, a positively tilted trough is forecasted to develop in the Western CONUS and makes its way towards the High Plains. For Thursday, this likely means a return to warmer temperatures ahead of the upper trough and as low surface pressure builds back into the area. However, ensembles show a wide range of solutions as to how the surface low and associated front develop and move across the Plains. There is also a fair amount of uncertainty in regard to the timing of the 500mb trough as suggested by high anomalies in the 500mb anomaly chart. At some point, the surface low pressure and front is forecasted to swing through the area which should usher in cooler temperatures behind it. The question is if this would be on Friday or Saturday (or maybe even Sunday) and would probably depend on how much the trough tilts. Another thing with this potential low pressure Thursday/Friday is that conditions could be windy as some guidance and ensembles show a deep low with a high pressure gradient. Will need to see how windy conditions will be as the system gets closer. So going into the end of the week, cooler conditions are likely though ensembles show a low chance that the majority of the cooler air stays north of the area. How cool isn`t clear at this time so currently have temperatures just a little below average. It is also worth mentioning that there is a low chance that high temperatures could be much cooler with highs closer to the 40`s. && .AVIATION...(For the 00Z TAFS through 00Z Monday evening) Issued at 509 PM MDT Sat May 14 2022 Both terminals will see VFR conditions during the forecast period. Main wx issue will be a cold front pushing through the area towards the second half of the forecast, allowing for northerly flow to ensue. There could be some VCTS for KMCK after 06z Sunday, but low confidence so have left out for now. Winds for KGLD, light/variable thru 08z Sunday, then west around 10kts. By 14z, northerly around 15-25kts, especially between 19z- 23z. Winds for KMCK, northeast around 10kts thru 13z Sunday, then north around 10-15kts. Gusts to 25kts from 18z onward. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ UPDATE...JN SHORT TERM...JRM LONG TERM...KAK AVIATION...JN
Area Forecast Discussion
National Weather Service Indianapolis IN
1138 PM EDT Sat May 14 2022 ...Updated Aviation Discussion... .Forecast Update... Issued at 1000 PM EDT Sat May 14 2022 Surface analysis late this evening shows a weak trough of low pressure tretching from NE OH across Indiana to a weak area of low pressure in place ovet he soutern plains. This trough was poorly organized. GOES16 shows convective debris clouds lingering across Indiana...with radar showsing the remnant convection diving south into southern Indiana. Aloft a stream of Pacific mositure and dynamcis was pushing across the western plains to the Ohio valley...with weak wave of forcing embedded within the flow. Earlier convection has resulted in surfac temps in the 60s amd cold pools from earlier convection are predominate. Overnight alack of forcing remains in pace and convective debris clouds are expected to continue to dissipate. Forecast soundings remain dry as do the time heights. Thus with no forcing...partly cloudy skies will be expecte along with lows in the upper 50s. Given current dew point depressions...some fog potential will be in place espcially with the rain that occured today. && .Short Term...(This evening through Sunday night) Issued at 125 PM EDT Sat May 14 2022 Flow is weak across the area today, between a dying upper low in the Southeast and a poleward lifting midlevel low north of the Dakotas. Latest ACARS sounding has 20-25 knot max flow in the troposphere. Surface winds are light and non-uniform, with a few corridors of convergence inferred. The most pronounced is now in western Indiana with the dying and very weakly baroclinic front tied to aforementioned lifting wave. This is where convection should become most concentrated later this afternoon. Weak shear should result in short-lived single- and multi-cells with the main hazard being brief strong to potentially damaging wind gusts. Hail is possible, but storm mode and relatively weak midlevel lapse rates should preclude a more substantial hail concern. Convection should tend to propagate southeastward given modest southerly mean flow convergent on the south side of cold pools. Storms should propagate southeast of the area and diminish later this evening. Please refer to mesoscale updates for more details on convective evolution through the afternoon and evening. Meanwhile, upstream Pacific jet will migrate eastward carving out a more pronounced shortwave trough at the base of the aforementioned Canadian low. This will offer stronger winds aloft, more shear, and forcing for ascent for our region tomorrow, leading to another round of convection. The thermodynamic/kinematic environment will be supportive of severe storms with damaging winds being the primary threat. There is still considerable uncertainty on upstream convective development Sunday afternoon, and MCS potential with a more organized wind threat into the area by evening. Low-level jet orientation may support more of a southeastward propagation, that would result in a path just southwest of the area. Even then, at least scattered development would be possible further north into our area, especially along the advancing front. Details on convective evolution and threats will become more clear tonight and tomorrow. && .Long Term...(Monday through Saturday) Issued at 125 PM EDT Sat May 14 2022 Post-frontal continental air mass will be drier and temperatures will fall to near climo for mid-May early next week. This will continue within mean northwesterly flow pattern until mid-week when deamplfying ridging nudges in. Even then, one or more perturbations in the flow will offer increased chances for showers and thunderstorms Tuesday night and beyond. At least initially, we`ll be in a warm moist advection pattern with deeper moisture and anomalous precipitable water values moving into the area and lingering through the end of the week. Shear and especially instability looks sufficient for strong to severe thunderstorm potential, but this will depend on convective evolution. Multiple rounds of convection are possible during this period. This may lead to some concern for flooding. && .Aviation...(06Z TAF Issuance) Issued at 1138 PM EDT Sat May 14 2022 IMPACTS: * Mainly VFR Conditions will be expected this TAF period. * Possible brief MVFR Fog overnight DISCUSSION: Outflow boundary cold pools were predominate across Central Indiana late this evening. Dew point depressions near 5F along with dissipating cloud cover...light winds and recent rain may lead to diurnal fog development overnight as RHs approach 90%+. With little to no forcing overnight expect skies to continue to gradually clear. Have included a tempo group near max rh hours to account for possible fog. Forecast soundings on Sunday again suggest attainable convective temps and HRRR shows an area of TSRA pushing across the forecast sites during the afternoon. Confidence remains low for specific timing on any storms. Thus have used a window of VCTS during the peak heating hours in the afternoon to account for this until confidence grows. Furthermore a strong wave aloft is hinted at arriving on Sunday evening. Forecast soundings here trend toward deep saturation during the late evening hours. Thus have again included a continued window of VCSH to account for possible showers. && .IND WATCHES/WARNINGS/ADVISORIES... None. && $$ Update...Puma Short Term...BRB Long Term...BRB Aviation...Puma
Area Forecast Discussion...UPDATED
National Weather Service North Platte NE
911 PM CDT Sat May 14 2022 .UPDATE... Issued at 910 PM CDT Sat May 14 2022 The RAP model shows fairly impressive moisture return across swrn Nebraska tonight viz a modest low level jet. This should produce precipitable water around an inch. The HRRR and RAP models also show a few thunderstorms developing across this area after midnight and the forecast gets an update for isolated thunderstorms overnight. The rest of the forecast is on track. The disturbance operating across nrn WY this evening should slice through nrn Nebraska overnight and Sunday morning. A note about thunderstorms tonight. An isolated severe storm or two is possible and large hail is the concern. Winds aloft are strong producing bulk shear between 40 and 50 kts plus temperatures upstairs are cold. The HRRR hail size product suggests the potential for 1 inch hail but the cold air and strong winds aloft could potentially produce larger hail. We will see...the best storm activity, if it develops would likely be after midnight. It is during this time the best moisture and forcing will be in place. && .SHORT TERM...(This evening through Sunday night) Issued at 259 PM CDT Sat May 14 2022 The primary concern for the short term will revolve around chances for thunderstorms tonight into tomorrow morning. Currently, a cold front has pushed through the area this afternoon, with weak northerly flow in its wake. Behind this front, temperatures have warmed into the upper 60s across northern Nebraska to near 80 degrees across southwest Nebraska. Agitated cumulus were noted along the diffuse frontal boundary just south of the area, stretching from roughly Benkelman to to just north of McCook to near Holdrege. High based thunderstorm development is possible along this boundary over the next couple of hours. That said, given frontal placement and anticipated storm motion, any activity should remain near/south of HWY 34, south of our area. For tonight, watching the eastward progression of a shortwave trough currently located over eastern WA/western ID. This shortwave is anticipated to zip quickly across the Rockies tonight, reaching the area by tomorrow morning. The approach of this shortwave will accomplish a couple things locally. First, flow will increase markedly aloft, with increasing shear anticipated. Hodographs look largely straight-line above the effective inflow base, though with ample speed shear in place. Additionally, cold air advecting in advance of this wave will steepen lapse rates in the mid-levels. Add in a sharpening warm frontal boundary near the KS/NE line and an increasing southerly LLJ and elevated thunderstorm development looks increasingly likely overnight. Where this occurs remains somewhat low confidence, though it appears the greatest chances will lie primarily east of Highway 83. High-res guidance suggests the bulk of any elevated supercell potential (and associated large hail risk) will remain across central and eastern Nebraska after Midnight CDT. Still, can`t rule out a stronger storm or two east of HWY 83 overnight. Outside of convective chances, increasing H7-H8 frontogenesis ahead of the ejecting shortwave will help to promote shower/thunderstorm development, primarily north of HWY 2 by early tonight. The greatest coverage looks to occur along the SD/NE border overnight, where forcing for ascent looks to be greatest. QPFs of around 0.1-0.2" are possible east of HWY 183, with the caveat that locally higher amounts would be expected in any sustained thunderstorm activity. For tomorrow, expect a quieter afternoon and evening, with surface high pressure settling over the area. Good dry advection and increasing subsidence aloft (with an upper ridge building into the Plains) should promote ample diurnal mixing tomorrow afternoon. This should help temperatures to climb into the 70s amid weak cold advection through the day. .LONG TERM...(Monday through Saturday) Issued at 259 PM CDT Sat May 14 2022 The aforementioned upper ridge will continue to be the primary synoptic driver into Monday, with a quick warmup anticipated. Widespread 80s return Monday afternoon, before the upper ridge begins to breakdown into Tuesday. By Monday evening, expecting another shortwave to approach from the west, with increasing thunderstorm chances anticipated over the higher terrain. Will have to monitor this potential with the possibility of some of this activity to work into the Panhandle and far southwest Nebraska. However, confidence in this remains low at this time. Convection chances increase again Tuesday evening as the upper shortwave crosses into the Plains and the surface low ejects across the lee side of the Rockies. This looks to drag a weak frontal boundary into the area, roughly bisecting the area. Ahead of this boundary, increasing instability and deep layer shear suggests the potential for strong to severe thunderstorms. Low level flow remains very meager through sunset, with forecast soundings showing largely straight-line hodographs. This would suggest a splitting supercellular mode, with large hail and damaging winds as hazards. The exception to this being along the surface warm frontal zone, where ample low level turning is indicated in forecast soundings. Will need to monitor the progression/placement of this boundary, as significant severe would be possible near it. Confidence remains low for now (in both placement of frontal boundaries and convective initiation), though this will be something that will need to be monitored closely. Confidence wanes beyond Tuesday, with a stronger upper wave progged to approach by late next week. Ensemble/deterministic guidance remains split with respect to timing and track, though this looks to be the next shot of precipitation locally. && .AVIATION...(For the 00Z TAFS through 00Z Sunday evening) Issued at 708 PM CDT Sat May 14 2022 Scattered showers are possible across portions of the area late tonight. A few thunderstorms are possible as well. Otherwise VFR conditions are expected to prevail. There is a small chance that ceilings of MVFR or lower could materialize around sunrise Sunday just before a cold front begins to quickly move southeast through the area. The probability of this occurring though is less than 30% chance and will not be included in any area TAF`s. VFR expected through the day Sunday. && .LBF WATCHES/WARNINGS/ADVISORIES... None. && $$ UPDATE...CDC SHORT TERM...Brown LONG TERM...Brown AVIATION...Taylor
Area Forecast Discussion
National Weather Service New Orleans LA
703 PM CDT Sat May 14 2022 .AVIATION...00Z TAF Package...VFR conditions over all terminals and likely to continue through much of the night. Convection is far less of a problem today but we could still see some isolated storms overnight. Only terminal that may see some minor impacts from vsbys could be MCB but confidence is low on that and likely MVFR the main concern. /CAB/ && .PREV DISCUSSION... /issued 249 PM CDT Sat May 14 2022/ SHORT TERM (Tonight through Monday)... Synoptic situation shows a trough pushing east-northeast from the SE Conus with northwest flow into the region around a building ridge to the west. This may allow for some thunderstorm activity later this afternoon and through the evening as shortwave move around the ridge diving into the back edge of the trough. Latest HRRR model runs show this more likely across the MS Gulf Coast area and west towards I-55 around 00z and running out of steam through the night time hours as the storms move mainly north to south and just leaves some coastal showers/thunderstorms through the overnight. Bagginess of the southern portion of the previously mentioned trough hangs across the the NE Gulf through Sunday...with slight nudge of the ridge in from the west...still a small chance for isolated to scattered showers and thunderstorms again Sunday afternoon and evening. Deeper upper level trough moving across the Great Lakes Sunday into Monday helps pick up the baggy wake upper low in NE Gulf and shuffles off to the east as the ridge builds some across the northern Gulf Coast Monday into Tuesday. Monday should be mainly dry...and very isolated shower or thunderstorm can not be ruled out...but we are talking 10-20 percent chance at most and mainly east of I-55 as the ridging will be taking hold across the western portions of the region. Temps will remain above normal through the period...around 90 tomorrow, and lower 90s will be common Monday. Average highs are around mid 80s for mid-May. LONG TERM (Tuesday through Saturday)... Flat ridging takes over the area by Tuesday and remains through the end of the week. Very strong agreement among the models for the period. Ridging will hold well above normal temps through the majority...if not all...of the week. Look for lower to mid 90s across the region each day with ample sunshine...and thankful note at this time is that the dewpoints should hold around upper 60s and lower 70s and not create "feels like" temps much higher than the middle to upper 90s...even with that said if you are not acclimated to this yet it can create heat stress and exhaustion issues quick in the nearly full sun that will be found each day. direct sunshine adds about 10-15 degrees to the stress on the body and should be considered if doing anything extraneous this week. Ridging drifts east some Thursday and starts to build across the far SE Conus Friday and will allow for deeper moisture to start to push in from the gulf as the surface high drifts well east of the area producing southerly flow Friday into Saturday...return of chances for showers and thunderstorms to start the weekend on Saturday with continued above average temps as well. -ABS MARINE... Low pressure to the east has likely made as much westward progress as it`s going to, as Great Plains trough should force it northward later tonight into Sunday. Another complex of thunderstorms will be possible overnight tonight that could impact the coastal waters. Otherwise, conditions should be relatively benign over the coastal waters, with the usual evening increase in winds over some of the eastern sounds and nearshore waters. -ABS PREV DISCUSSION... /issued 1247 PM CDT Sat May 14 2022/ AVIATION... 18Z TAFS...VFR conditions across the area right now with light northerly winds across much of the region. As we reach peak heating showers and thunderstorms will likely start to develop across the region in a scattered fashion with possibly a slightly higher concentration east of I-55. Have VCTS through the afternoon and evening hours and added tempo 4sm TSRA at those sites east of I-55 as well...winds may be gusty around storms. After sunset should lose the storms and it is possible a few areas will see modest fog develop...have nothing going below 4sm at this time, but it could be a product of rainfall from this afternoon/evening and something to watch for later as we see where the rain falls. By mid morning VFR conditions will be likely across the region with light and variable winds. -ABS MARINE... Low pressure to the east has likely made as much westward progress as it`s going to, as Great Plains trough should force it northward later today into Sunday. Another complex of thunderstorms will be possible overnight tonight that could impact the coastal waters. Otherwise, conditions should be relatively benign over the coastal waters, with the usual evening increase in winds over some of the eastern sounds and nearshore waters. 35 && .PRELIMINARY POINT TEMPS/POPS... MCB 65 89 66 91 / 50 20 10 20 BTR 65 90 68 92 / 30 30 0 20 ASD 65 90 68 92 / 60 30 10 20 MSY 70 88 72 91 / 30 30 10 10 GPT 68 88 70 91 / 60 30 10 20 PQL 66 89 68 92 / 60 30 10 10 && .LIX WATCHES/WARNINGS/ADVISORIES... LA...None. GM...None. MS...None. GM...None. && $$