Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 08/01/19

Area Forecast Discussion
National Weather Service Bismarck ND
1040 PM CDT Wed Jul 31 2019 .UPDATE... Issued at 1040 PM CDT Wed Jul 31 2019 The remainder of the severe thunderstorm watch has been allowed to expire as scheduled. UPDATE Issued at 947 PM CDT Wed Jul 31 2019 As expected, storms are diurnal in nature and have been downtrending the past hour or so. Will allow the watch to continue north central through the next hour where some robust convection continues. Otherwise the majority of the watch has been expired. UPDATE Issued at 550 PM CDT Wed Jul 31 2019 Severe thunderstorm watch number 548 has been issued for most of western and north central North Dakota this evening. Storms have initiated across the west and have gradually increased in intensity as the capping inversion erodes. Steep lapse rates and decent shear around 35 kts will create a favorable environment for large hail. Winds will become a threat as storms collapse. Storm motion has been slow, so will also be looking at heavy rain producing a flash flood threat. Convection is expected to be diurnal with lack of good mid level forcing, so the main window for severe will be this evening. Little to nothing is expected over my southeastern areas with weaker lapse rates and stronger inhibition. && .SHORT TERM...(This afternoon through Thursday) Issued at 234 PM CDT Wed Jul 31 2019 A slight risk for isolated strong to severe thunderstorms highlights the short term forecast. Currently, a large area of low pressure is centered across eastern Montana, southern Saskatchewan, and far western North Dakota, with a frontal boundary oriented northeast to southwest. As this boundary slowly pushes east, isolated to scattered showers and thunderstorms are expected to form along this line in a moderately unstable environment in western North Dakota. Temperatures along the MT/ND border are in the mid 80s, expected to rise to the low 90s, while low cloud cover across parts of central North Dakota has really hindered daytime heating. Southerly winds ahead of the front have been advecting in moisture, with surface dew points in the mid to upper 60s. Main thinking right now is that this is a conditional severe threat, with RAP sounding analysis hinting that convective inhibition will be quite strong across central North Dakota, but somewhat weaker across the west especially if surface temps continue to rise. MUCAPE values range from 1500-2500 J/kg and model guidance shows steep low level lapse rates, but deep layer shear is only around 25-30 knots. The shear does look to be almost perpendicular to the boundary, so expecting a mostly discrete storm mode, which will help enhance the isolated wind/hail threat. HREF updraft helicity tracks are short and scattered so again thinking this will be an isolated threat that won`t extend much into central North Dakota. Chance of storms dies off rather quickly tonight as this event is mainly diurnally- driven, with low temperatures tonight in the upper 50s north to mid 60s south. On Thursday, the upper-level ridge becomes centered over the Northern Plains with the same frontal boundary from today becoming oriented much more west to east through the center of North Dakota. A shortwave moving through the mean flow will help heights be more neutral to slightly falling, compared to height rises today, which will help with more overall ascent. The chance for scattered showers and thunderstorms returns in the afternoon with another moderately unstable environment developing and high temperatures in the mid to upper 80s. .LONG TERM...(Thursday night through Wednesday) Issued at 234 PM CDT Wed Jul 31 2019 Almost daily thunderstorm chances before a slight cool down next week highlights the extended forecast. As upper level ridging continues through the weekend, North Dakota will remain in a pretty typical summer weather pattern with warm temperatures and almost daily chances for showers and thunderstorms. Thursday and Friday night both have widespread chances for thunderstorms across all of western and central North Dakota as shortwaves move through the ridge and instability remains high, but still a large amount of uncertainty in storm severity and location. Model guidance is hinting at a cold front moving south through the region for the start of next week, with forecast high temperatures in the low 80s for the beginning of the work week. && .AVIATION...(For the 00Z TAFS through 00Z Thursday evening) Issued at 550 PM CDT Wed Jul 31 2019 Scattered showers and thunderstorms are possible mainly in western and north central North Dakota this evening but low confidence in specific location so did not include any TEMPOS at this time. Did mention VCTS for KDIK with storms just to the west- southwest of the Dickinson airport. Winds are primarily around 10 knots from the south-southeast with a cold front approaching western North Dakota. Low cloud deck expected to move into southern North Dakota early tomorrow morning, possibly lowering ceilings to MVFR at KDIK/KBIS/KJMS. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...NH SHORT TERM...MJ LONG TERM...MJ AVIATION...NH
Area Forecast Discussion
National Weather Service Brownsville TX
631 PM CDT Wed Jul 31 2019 ...00z Aviation Update... .DISCUSSION...Updated for latest aviation discussion below. && .AVIATION...A very quiet TAF period ahead with VFR conditions expected to prevail. Light southeasterly winds (10kts or less) expected. Only high clouds from remnant convection upstream, but again it`s difficult to find much to talk about through this cycle. Safe Travels! && .PREV DISCUSSION... /issued 247 PM CDT Wed Jul 31 2019/ SHORT TERM (Now through Thursday Night): It`s been a hot, but relatively quite day, weather-wise, across the Rio Grande Valley and Deep South Texas. KBRO doppler radar shows a dissipating cluster of thunderstorms just north and east of the BRO offshore coastal waters, moving southwest. A slightly drier and more stable airmass in place over the RGV will likely continue eroding this activity. This is confirmed by the latest hi-res HRRR model, which shows the storms dissipating before reaching any land areas. Will continue to monitor this activity, just in case. The seabreeze has been uneventful thus far, currently draped across the immediate coastline of all three coastal counties. Not expecting much precipitation development along the seabreeze this afternoon, but cannot completely rule out an isolated shower/thunderstorm or two before sunset. A stout 595dam ridge current centered over the TX/OK Panhandles will remain stagnant over that same area over the next couple of days. Temperatures are forecast to trend closer seasonal average tonight through Thursday night as slightly drier air and cooler 850mb temperatures. Highs will be in the mid-upper 90s east of I69C and near 100 to 103 degrees west of I69C; lows will generally be in the mid-upper 70s. Rain chances will be minimal through Thursday night, with the best chances occurring off the coast. Kept in 20% pops east of I69C through the morning and day on Thursday, but only expect isolated convection with limited moisture available. As far as fire weather concerns: Relative humidity values will continue to be in the 20 percent range for western portions of Deep South Texas on Thursday afternoon. However, wind speeds are expected to be below criteria for fire weather concerns. LONG TERM (Friday through Wednesday): The persistent mid level Monsoon ridge over the Southwestern States into the South Central Plains will continue into the long term and will shift slowly west through the weekend as a broad 500 mb trough digs into the Gulf of Mexico. The combination of the persistent mid level weakness over the Gulf and ample low level tropical moisture should support isolated to scattered convection near the lower Texas coast and over the Gulf Waters, if not weak daily sea breezes. The 500 mb ridge will build into North Central Mexico and West Texas by early next week. Temperatures will trend toward above normal through the forecast, with afternoon heat index values of 103 to 108 through the weekend, and a skosh higher, 105 to 110 degrees going into the next work week. The global models, though not in unequivocal agreement, are in fair agreement for this neck of the woods with no apparent major weather distractors. Will therefore lean toward a model consensus. MARINE...(Now through Thursday Night): No major changes made to forecast from this morning. Marine conditions will be generally favorable for the short term period featuring light to moderate southeasterly winds and low seas. Isolated to scattered showers along with thunderstorms may be possible at times, especially offshore from 20 to 60 nm out. Heavier showers or thunderstorms may result in locally gusty winds and isolated agitated seas. Friday through Monday Night: Light to moderate southeast winds and low to moderate seas will prevail through the forecast. There will be isolated showers and thunderstorms. Mid level ridging centered roughly over the southwest United States will counterbalance broad mid level troughing over the eastern sections of the country, which will extend south to over the north central Gulf. The combination of moisture moving up from the south on the large scale southeast flow will be modestly destabilized by the weakness aloft, supporting marine convection. && .BRO WATCHES/WARNINGS/ADVISORIES... TX...None. GM...None. && $$ This product is also available on the web at: HTTP://WEATHER.GOV/RGV Aviation Update...Frye-55
Area Forecast Discussion
National Weather Service Dodge City KS
1055 PM CDT Wed Jul 31 2019 ...Updated Aviation... .SHORT TERM...(This evening through Thursday) Issued at 202 PM CDT Wed Jul 31 2019 Very weak cyclogenesis will be developing are area of enhanced surface convergence across southwest and central Kansas late this afternoon through the overnight. The CAMs have been showing for many runs now isolated to scattered convection within this low pressure area as early as 21 UTC, initiating in far southwest Kansas and expanding into the I-70 corridor around Hays and Wakeeney by around 7 or 8 pm. Deep layer shear is generally weak as the upper ridge has dominated the area for days, however steep mid level lapse rates will promote deep updrafts and a threat for perhaps a marginally severe wind gust and locally heavy rain and lightning continuing through the late evening hours far beyond sunset. Beyond the convective threat through the late evening, the lows tonight should be very warm in the mid 70s across the central Kansas counties, and not as warm out in the higher elevation counties near the Colorado line. .LONG TERM...(Thursday night through Wednesday) Issued at 221 PM CDT Wed Jul 31 2019 A cold front on Friday may be the focus for a few thunderstorms, again weakly sheared, so severe threat should be minimal. Light easterly upslope will develop after the frontal passage, with a number of days to follow with continued persistent upper ridging across the southern Rockies and central/southern High Plains. && .AVIATION...(For the 06Z TAFS through 06Z Thursday night) Issued at 1055 PM CDT Wed Jul 31 2019 VFR will continue to prevail through this TAF cycle. Mid level convective debris clouds will gradually dissipate overnight, with surface winds light and variable in direction. A weak wind shift or frontal boundary will sag southward through SW KS daylight Thursday, keeping surface winds highly variable in direction at GCK/DDC (but generally less than 10 kts). Light NE winds will prevail at HYS Thursday north of the boundary, while SW winds prevail with modest gusts at LBL south of the boundary. Scattered to broken mid layer cloud decks are expected. Carried no convection in this set of TAFs and kept the airports dry. Thunderstorms in NE Colorado 00-03z Fri may organize into a complex and approach the airports 03-09z Fri, as shown by the latest HRRR iterations. Confidence is low on coverage this far out. Models do show a reinforcing cold front surge with enhanced N/NE winds of 15-25 kts near the end of this TAF cycle (near 06z Fri). Consensus of short term models suggest that post-frontal IFR stratus cigs are possible Friday morning. && .PRELIMINARY POINT TEMPS/POPS... DDC 74 102 73 94 / 20 0 10 0 GCK 70 101 69 92 / 40 0 10 10 EHA 71 100 69 93 / 10 0 10 20 LBL 71 101 72 93 / 10 0 10 10 HYS 72 96 71 89 / 40 0 20 10 P28 74 103 75 97 / 10 0 10 10 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...Russell LONG TERM...Russell AVIATION...Turner
Area Forecast Discussion
National Weather Service Grand Forks ND
1000 PM CDT Wed Jul 31 2019 .UPDATE... Issued at 1000 PM CDT Wed Jul 31 2019 Thunderstorms moving down from Canada have increased in strength a bit as they cross the border into Cavalier county. With ML CAPE values around 3000 J/kg and effective bulk shear of 30-35 kts think that strength will be maintained for a bit longer until we start to lose residual heat from daylight. Bumped up POPs a bit across our far north for the next few hours. CAMs have the cells slowly sinking south across the Devils Lake Basin and northern RRV, with the HRRR most bullish on convection holding together past 06Z. Other CAMs and even other runs of the HRRR are not as strong. Have POPs slowly tapering to isolated after the 06-08Z time frame, and will adjust if needed. && .SHORT TERM...(This evening through Thursday) Issued at 335 PM CDT Wed Jul 31 2019 The main challenge for this time frame is thunder chances. Currently not a lot is happening. There was a lot of cloud cover west of the FA this morning, which limited the heating somewhat. However it is fairly clear now with temperatures back into the low 80s and dew points in the mid 60s to low 70s. This is giving surface based CAPE values of 3000+ J/kg over western and central ND with just a little CIN left. Effective shear is around 30 knots and precipitable water values at about 1.2 to 1.3 inches. Surface boundaries are a little diffuse. However high resolution models do show storms developing over western ND in the late afternoon and early evening. Some of these storms may hold together as they reach the Devils Lake region by mid to late evening. However, the sun will be setting by then and the low level jet and 850mb warm advection is not that impressive. Therefore think these storms will weaken as they approach the Devils Lake region. Think most activity will diminish by late evening, but some of the high resolution models show a shower or weak storm lingering into the overnight hours up along the Canadian border. Thunder possibilities into Thursday are a bigger challenge. A remnant surface boundary may be draped across the northern half of the FA on Thursday. Some models show additional shower and weaker storm activity lingering in the morning, but there are better chances for a few strong to severe storms again by afternoon. The northern half of the FA remains in a marginal risk, so the potential is there. .LONG TERM...(Thursday night through Wednesday) Issued at 335 PM CDT Wed Jul 31 2019 Lots of uncertainty by Thursday night, so pretty much left low precipitation chances across the entire FA. Should have a better idea on how much activity may linger Thursday night with later forecasts. Thunderstorms will be possible for late day and eve Fri, but weak forcing for ascent will allow for only isolated storms. Continued weak deep layer shear will also limit the severe potential. What we will have at the surface should be a weak synoptic boundary somewhere over the northern forecast area below mainly northwest flow aloft. This northwest flow will always make it difficult to pinpoint spatial and temporal extent of storms, but there is indication of a somewhat more substantial surface boundary and associated upper wave for later Sun. Another opportunity presents about 24 to 36 hours later, then a more zonal upper pattern could make for a more settled dry period Tue into the middle of next week. Temps during the period will rise to above average levels, mainly in the mid to upper 80s Fri through Mon, trending down a bit thereafter. Lows will be in the balmy 60s much of the time. && .AVIATION...(For the 00Z TAFS through 00Z Thursday evening) Issued at 614 PM CDT Wed Jul 31 2019 VFR conditions throughout the period. The high resolution models have some convection entering the KDVL area later in the evening, which makes sense given cells starting to form in southern Manitoba. Have VCTS at KDVL but will keep it out of the TAF sites further east. Winds gusting above 20 kts at some sites will subside after sunset, with winds from the south at less than 10 kts for the rest of the period. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...None. MN...None. && $$ UPDATE...JR SHORT TERM...Godon LONG TERM...WJB/Godon AVIATION...JR
Area Forecast Discussion
National Weather Service Goodland KS
542 PM MDT Wed Jul 31 2019 .UPDATE... Issued at 542 PM MDT Wed Jul 31 2019 Updated forecast for this evening and tomorrow to adjust thunderstorm chances. High resolution guidance suggest storms will likely remain in the southern portion of the forecast area although attention will need to be paid along the I-70 corridor as storms have developed in northeast Colorado and additional storms may develop. For tomorrow, high resolution guidance indicating a larger complex of storms forming in northeast Colorado, spreading through the region in the evening hours (6 pm to Midnight mountain time). Some storms may be severe with damaging winds as the main threat. Would not rule out some large hail, some very large hail due to the expected instability. Tomorrow`s situation definitely bears watching. && .SHORT TERM...(This evening through Thursday night) Issued at 400 PM MDT Wed Jul 31 2019 Overview: Modest W-NW flow aloft will persist over the Tri-State area -- on the northeast periphery of an upper level ridge centered over New Mexico. Today-Tonight: Weak low-level convergence invof a broad surface low (centered near Lamar CO) -- and an associated thermal/ moisture boundary extending northeast from Lamar-Tribune-Gove City-Hill City -- will serve as a focus for convective development this afternoon. Per 21Z SPC mesoanalysis, MLCAPE values across the Tri-State area ranged from 500 J/kg (eastern CO) to 1000-1500 J/kg (western KS), though a significant amount of convective inhibition persists north of the TMB (north of I-70) where 100-200 J/kg of CINH persists near the KS/NE border. Simulated reflectivity forecasts via the 18Z NAM NEST and past several runs of the HRRR are (1) doing a good job in depicting ongoing convection invof Hwy 50 this afternoon and (2) are consistent with the latest mesoscale/ thermodynamic environment analyses. With this in mind, expect isolated unorganized thunderstorms to largely be confined south of I-70 this aft/eve -- primarily in Kit Carson/Cheyenne counties in CO and Greeley/Wichita/Gove/Logan counties in KS - with activity gradually waning/dissipating after sunset. Thu-Thu night: With little change in the synoptic pattern, the convective forecast on Thursday may largely be a function of upstream convection. More specifically, guidance suggests that mesoscale features emanating from deep convection over Wyoming tonight/tomorrow morning may aid/enhance diurnal development along the CO Front Range tomorrow afternoon -- and that the ensuing activity will propagate SSE into eastern CO between 00-06Z. Though an MCV may well keep convection going after sunset, activity is still likely to wane/dissipate by midnight -- possibly without crossing the CO/KS border. .LONG TERM...(Friday through Wednesday) Issued at 125 PM MDT Wed Jul 31 2019 At the start of the period, an upper ridge extends across the Rockies, with high pressure centered over the Four Corners. The tri- state region is under northwest flow on the eastern side of the ridge as a result. A disturbance continues on its way around the periphery of the ridge on Friday, generating chances for showers and thunderstorms mainly in the afternoon and evening hours across the area. The pattern remains similar through the weekend, with the ridge staying west of the High Plains. No major weather disturbances are anticipated on Saturday or Sunday, leading to a dry forecast at this time. However, will need to monitor the potential for a couple of weak waves triggering storm development. Daily precipitation chances return early next week, with a possibility of thunderstorms each afternoon and evening Monday through Wednesday. Current guidance suggests the ridge is pushed somewhat southward with a series of shortwaves rotating through the flow. Models differ during this timeframe, making it difficult to have confidence or pin down details at this time. High temperatures are forecast in the 80s on Friday and Saturday, followed by a warming trend Sunday (near 90 degrees) and Monday (90s region-wide). Tuesday and Wednesday look slightly cooler in the upper 80s to low 90s. Low temperatures range in the upper 50s to upper 60s throughout the period. && .AVIATION...(For the 00Z TAFS through 00Z Thursday evening) Issued at 542 PM MDT Wed Jul 31 2019 VFR conditions anticipated through this evening. However, things should change by tomorrow morning as low level moisture moves into the region through the northeast surface flow. Anticipating MVFR conditions due to stratus. There could also be some reduced visibility from fog but confidence in this wasn`t too certain at the moment. This may need to be adjusted later this evening. Other concern to discuss is thunderstorm chances. There may be an isolated storm near KGLD this evening so inserted a brief VCTS period. Tomorrow evening, expecting a larger complex of storms to move across the forecast area which would likely impact KGLD. KMCK may be on the edge. Other than some brief gusty northeast winds this evening, no other aviation concerns are expected. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ UPDATE...RRH SHORT TERM...VINCENT LONG TERM...JBH AVIATION...RRH
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