Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 06/25/17


Area Forecast Discussion
National Weather Service La Crosse WI
940 PM CDT Sat Jun 24 2017 .SHORT TERM...(Tonight through Sunday Night) Issued at 150 PM CDT Sat Jun 24 2017 Scattered showers and thunderstorms moving across parts of southeast MN at this time ahead of a potent mid-level PV-anomaly pushing southeastward through central MN. Latest RAP shows lobe of 700-300 PV-advection pushing in with this wave and is expected to continue fueling shower/thunderstorms into early this evening. Will be watching for a few stronger storms capable of small hail and sub- severe wind gusts in the 40-50 mph range as RAP also showing decent 30-35kt bulk shear along/south of I-90 with MUCAPE in the 500- 1000J/kg range. Look for a diminishing trend later this evening and pretty much precipitation-free by midnight with loss of surface heating and as we get on the subsident side of the passing wave. Otherwise, rest of tonight looks to be a chilly one with lows dipping into the mid 40s to near 50. Another round of scattered showers and isolated thunderstorms expected to develop by late Sunday morning, lasting into the evening with lingering cold cyclonic flow aloft. In addition, models bring another mid-level trough through. Bulk of these showers/isolated storms expected to be east of the Mississippi River and most concentrated northeast of I-94, closer to the better mid-level forcing and steeper lapse rates. Otherwise, plan on significantly cooler than normal highs Sunday only in the 60s with lows Sunday night in the middle 40s to near 50. .LONG TERM...(Monday through Saturday) Issued at 150 PM CDT Sat Jun 24 2017 Cool cyclonic flow continues through Monday for lingering small-end shower/isolated thunder chances, mainly east of the Mississippi River. Look for highs in the 65-70 degree range. High pressure builds across the region for Monday night through Tuesday for dry/warmer conditions. Temperatures still look to be some 5 to 10 degrees below normal, but do not think there will be any complaints as highs Tuesday top off in the 70s. Latest GFS/ECMWF in good agreement in pushing an area of low pressure and cold front into/through the region Tuesday nigh through Thursday night for the likelihood of showers and thunderstorms. Will have to keep an eye on the possibility for strong to severe storms centered on Wednesday. The GFS shows fairly boisterous MUCAPE in the 2000-3800J/kg range while the EC only shows 500-1500J/kg. Plenty of available Bulk Shear in the 35-45kt range. Westerlies aloft bring a couple more short wave trough across the region Friday through Saturday for continued shower/thunder chances. Otherwise, no big warm-ups on the horizon with fairly high-zonal flow. Looks like highs in the middle 70s to lower 80s Thursday and in the 70s Friday/Saturday. && .AVIATION...(For the 06Z TAFS through 06Z Sunday night) Issued at 940 PM CDT Sat Jun 24 2017 Cigs: Modeled RH fields and current satellite imagery show an area of mvfr/vfr cigs sinking southeast across nd/northern MN - with the models bringing it across the TAF sites by 12z Sun (or so). Should get a little diurnal bump as Sunday wears on, and likely scattering out Sunday evening. WX/vsby: Another round of shra/ts similar to today for Sunday, as a shortwave/favorable low level lapse rates/instability work on the available moisture. Perhaps a bit better chances east of the Mississippi river. Main threat time would be from 19-00z. See some threat for valley fog at KLSE for the first part of the overnight tonight - especially if winds remain decoupled. Clouds coming in from the north and 10 kts or greater winds just off the deck will be limiting factor. Shallow? Will leave P6SM for the moment, but trends will monitored. Wind: west northwest through Sunday. Will stay up mostly tonight, although could stay decoupled at KLSE until sunrise, then increase some on Sunday. Expect some gustiness by late morning, with again enhanced gusts around any stronger shower/storm. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...None. MN...None. IA...None. && $$ SHORT TERM...DAS LONG TERM....DAS AVIATION.....Rieck
Area Forecast Discussion
National Weather Service Binghamton NY
1011 PM EDT Sat Jun 24 2017 .SYNOPSIS... Partly cloudy skies and scattered showers will taper off overnight in northeast Pennsylvania and the Catskills with light and variable winds. Unsettled weather will prevail in the forecast Sunday through Tuesday with cool temperatures. Dry weather is expected to return on Wednesday. && .NEAR TERM /THROUGH SUNDAY NIGHT/... 1000 PM update...radar shows ana area of showers across northeast PA into Sullivan County NY. NAMnest 3km from 18z nailed the evolution of this precipitation as it moved into northeast PA/Sullivan Co. NY. The model was off just a bit but the latest HRRR was too far south at this time. For POPs we extrapolated this precipitation out of northeast PA and Sullivan Co. NY by 7z or so. This precipitation was forming as a boundary drops southeast into this area associated with the short wave moving across the eastern Lakes. Rest of forecast area will see scattered to broken clouds to start the overnight with some clearing later tonight. 630 PM EDT Update...radar shows isolated to scattered showers helped by a short wave moving east-northeast from the eastern Lakes toward southern Quebec. This wave was providing some lifting in the presence of diurnal heating. The NAM 3km nest was doing very well with the precipitation at this time and have used its hourly reflectivity output as a starting point for hourly POPS. This model as well as the HRRR which looks a little overdone bring some showers down into Northeast PA between 22z and 01z before exiting. The loss of the daytime heating combined with the passage of the short wave will lead to the demise of all precipitation by late evening. Otherwise made no significant changes to forecast beyond midnight. 250 PM EDT Update... A diurnal cu field has developed across the region in the wake of this mornings cold front. Cool air aloft, low-lvl moisture and the summer`s sun will allow this deck to continue through the afternoon. Around sunset the deck will start to dissipate and mostly clear skies will prevail through much of the night. Some thunderstorms have developed along the lake breeze in western NY. Do not believe this activity will reach our area, but it is possible we may see an isolated rain shower over central NY. Sfc temps are currently in the mid/uppr 70s over central NY and uppr 70s/low 80s over NEPA. Expect temps to rise a few more degrees this afternoon, and fall into the low/mid 50s tonight as 850MB temps fall a few degrees overnight. Tonight the next mid-lvl shortwave trough approaches from the west and the broad uppr lvl long-wave trough shifts towards the northeast. This are our next features to generate showers and thunderstorms over the region. These features will move many embedded waves over the region, none of which particularly strong, but enough dynamic lift aloft to possibly generate scattered showers. Believe these showers will be mostly diurnally driven in nature and the best chance for showers will be during peak heating. Sunday afternoon temps will be slightly cooler than today, ranging in the uppr 60s/low 70s over central NY and 70s over NEPA (uppr 70s over far se NEPA). Sunday night a secondary front will move across the region and 850MB temps will fall to around 5 deg C. (which are quite impressive) This amount of CAA will result in some minor lake enhanced rain showers over the region, thus the chance for rain showers over central NY will linger through the night. Temps Sun night will fall into the low/mid 50s. && .SHORT TERM /MONDAY THROUGH TUESDAY/... Unsettled weather continues in the short term with a long wave trof over the Great Lakes. Short waves rotating through the trof along with surface trofs and fronts will increase the chance for afternoon showers and thunderstorms both Monday and Tuesday. There is also the chance of a shower even outside of the peak heating hours. With the upper low in place, temperatures will average below normal both days. && .LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... Perhaps a brief break in the showers Wednesday as the upper trof lifts and some ridging as the surface builds in on Wednesday into Thursday. Later Thursday a strong wave flattens the SE ridge and drapes a surface front over the area. This will be the focus of low level convergence and showers and thunderstorms. Front moves little so do not expect much of a change into Friday with continued showers and thunderstorms, especially in the afternoon and evening. && .AVIATION /02Z SUNDAY THROUGH THURSDAY/... Scattered showers are moving across the southern tier of NY and the northern tier of Pa early this evening. These showers will produce a brief shower at BGM and could graze AVP with a brief shower later this evening. Skies will become clear to partly cloudy overnight with VFR conditions. VFR conditions will continue on Sunday with sct-bkn clouds developing. Scattered showers will develop during the mid-to-late afternoon with coverage too low to include at any of the TAF sites at this time. Winds will be variable or southwesterly at less than 10 kts tonight then southwest increasing at around 10 kts on Sunday. Outlook... Sunday - Tuesday...Mostly VFR, but restrictions are possible with occasional showers and thunderstorms. Wednesday...VFR. Friday...Restrictions likely in showers and thunderstorms. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...None. NY...None. && $$ SYNOPSIS...DJN/KAH NEAR TERM...DJN/KAH SHORT TERM...DGM LONG TERM...DGM AVIATION...KAH/MSE
Area Forecast Discussion
National Weather Service Denver/Boulder CO
815 PM MDT Sat Jun 24 2017 .UPDATE... Issued at 753 PM MDT Sat Jun 24 2017 Nwly flow aloft remains over the area with axis of upper level jet across the far ern plains. This type of set up could lead to some nocturnal tstm activity so will keep in some low pops overnight across the far ern plains. && .SHORT TERM...(This evening through Sunday) Issued at 330 PM MDT Sat Jun 24 2017 Northwesterly flow aloft continues today with slightly higher midlevel moisture pushing into the northern state border due to a shortwave. ACARS soundings show the cap weakening over the plains, this will help showers and weak storms form over the higher terrain and Palmer Divide area later this afternoon and push southeast into the early evening. The shortwave should provide a northeasterly push with slight increase in midlevel moisture, with the HRRR continuing to show convection forming over Larimer County foothills. Recent runs however have been keeping in the high terrain, signaling the plains remaining too capped. Satellite trends seem to favor the cap holding at least for the next couple hours. High surface pressure will remain over the Great Plains through Sunday, keeping east to southeasterly flow into the area. Look for slightly warmer temperatures Sunday which will help obtain low amounts of CAPE with the available moisture. There will be a slight chance of showers and weak thunderstorms over most of the area except the northern Front Range urban corridor where models hold CIN over. .LONG TERM...(Sunday night through Saturday) Issued at 330 PM MDT Sat Jun 24 2017 On Monday...high pressure ridge aloft will move over Colorado with warming temperatures expected over the plains. Still moisture will be rather limited under the ridge with mainly isolated late day storms over mountains and higher terrain. On Tuesday the ridge will shift east of Colorado into the central plains and replaced with a more westerly flow aloft and a jet streak over northern sections of the state. There should be a bit more moisture with the flow for isolated showers/storms over much of Northern Colorado. For Thursday and Friday, the flow will shift west to northwest and appears there will be several frontal boundaries which will cool temperatures again to below seasonal normals. May see a bit higher chances of showers late in the week with more low level moisture available along with a trof passage late thursday and Friday. && .AVIATION...(For the 00Z TAFS through 00Z Sunday evening) Issued at 753 PM MDT Sat Jun 24 2017 Denver cyclone was se of the airport with ely lvl winds. Winds may stay ely thru 06z and then go to more sly by 09z. Ceilings will remain in the 8000-9000 ft range thru 09z with no ceilings expected between 09z and 15z. && .BOU WATCHES/WARNINGS/ADVISORIES... None. && $$ UPDATE...RPK SHORT TERM...Kriederman LONG TERM...Entrekin AVIATION...RPK
Area Forecast Discussion
National Weather Service Caribou ME
913 PM EDT Sat Jun 24 2017 .SYNOPSIS... A weak ridge of high pressure will prevail over the area overnight. An upper level trough of low pressure will remain to our west through early this week. The trough will lift out during the mid week period as high pressure builds to our south. && .NEAR TERM /THROUGH SUNDAY/... 9:13 PM Update...One cold front has pushed off the coast, but there is a secondary cold front across Quebec this evening. Scattered showers ahead of this front appear to be enhanced by a mid to upper level disturbance. The HRRR has a reasonable depiction of these showers, and the HRRR would have the last of them ending by around or just after midnight across the eastern zones. The main adjustment was to the PoP/Wx grids for the next few hours to account for these showers. Otherwise, only minor tweaks based on the latest observations. Previous discussion... Most of the shwrs have already moved out of the Rgn as of mid aftn as drier llvl air moves into Rgn from QB. Any isold shwrs should end by erly eve as a weak ridge of hi pres tries to exert some influence ovr the Rgn later tngt, allowing for clrg and and some radiational cooling ovr Nrn broad rvr vlys. Sun will begin fair, but then aftn clds and eventually mid to late aftn shwrs and a few tstms will develop as an upper trof/low from SE Ont begins to apch. With sig lower PWs and fast mid troposphere flow as evident by Corfidi vectors, rnfl potential will be less with fast moving shwrs and tstms than last ngt and this morning. Both lows tngt and hi temps Sun will be near seasonal norms. && .SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/... Our weather pattern will remain a bit unsettled as the new week begins with a shallow trough of low pressure remaining to our west as weak disturbances track out of this trough and across our area. Some spotty showers and thunderstorms may be around Sunday evening as one disturbance and a weak surface trough move across the area. Another weak disturbance and surface trough will move through on Monday bringing another chance for spotty showers and isolated thunderstorms. The best chances for showers Monday will be over the higher elevation to the west. Another slightly stronger disturbance will lift out of the trough and slide across the region late Monday night into Tuesday with a better chance for more showers. Some thunderstorms may form across central and interior Downeast locations along and just south of a weak surface boundary over the region Tuesday afternoon. && .LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... The upper trough which will be to our west during the early week will lift out to our north on Wednesday. As it does, it will pull a weak cold front across the area bringing another chance for scattered showers and some isolated thunderstorms. High pressure will build to our south during the mid-week period and warm, humid air pushing north around the high will push north against a frontal boundary dividing the warmer air to the south from cooler air to the north in eastern Canada. A low tracking along this front will bring a chance for rain late Thursday into Friday. High pressure dropping down from Canada may then bring drying for early next weekend. && .AVIATION /01Z SUNDAY THROUGH THURSDAY/... NEAR TERM: VFR xpctd all TAF sites xcpt briefly MVFR late this evening at the northern Taf sites in showers, and Sunday aftn in any tstm or heavier shwr. SHORT TERM: MVFR to VFR conditions are likely Sunday night into early Monday with VFR conditions likely Monday afternoon. Conditions may drop back to MVFR Monday night into early Tuesday, with localized IFR conditions in fog possible Downeast. Generally VFR to MVFR conditions are then likely Tuesday night into Wednesday. && .MARINE... NEAR TERM: The seas are still around 6 feet as of 9 PM, so will extend the small craft advisory for hazardous seas for our outer zones until 1 AM Sunday. Both the wind and seas should subside later tngt into Sun. Still some areas of dense fog over the waters, but that should see vast improvement later this evening as the cold front pushes offshore. SHORT TERM: Winds and seas are expected to be below SCA Sunday night through early next week. Humid air over the cold waters will likely result in fog limiting visibilities at times through early next week. && .CAR WATCHES/WARNINGS/ADVISORIES... ME...None. MARINE...Small Craft Advisory for hazardous seas until 1 AM EDT Sunday for ANZ050-051. && $$ Near Term...CB/VJN Short Term...Bloomer Long Term...Bloomer Aviation...CB/VJN/Bloomer Marine...CB/VJN/Bloomer
Area Forecast Discussion
National Weather Service Houston/Galveston TX
946 PM CDT Sat Jun 24 2017 .DISCUSSION... The rain activity has tapered off to isolated showers at 9:30 PM with the most activity located near the front which was draped across the northern counties of the forecast area. Isolated showers were also occurring between Houston and Galveston near the radar. Another area with scattered showers developing was along an outflow boundary located along the west of Freeport. Still expect isolated to scattered showers and thunderstorms across Southeast Texas through the remainder of tonight. Numerous weak boundaries set down by earlier convection, the main outflow boundary along the coast and the front in the north will all be a focus for development. PW/s from the 00Z soundings ranged from 1.7 inches at CRP to 2.0 at LCH. This indicated plenty of moisture will be available. Model soundings show an increase in the PW field throughout the night. The area will also be under a weak upper level trough of low pressure. Tweaked the rain chances downward for the remainder of this evening. Kept rain chances as is for the overnight period. 40 && .PREV DISCUSSION... /ISSUED 641 PM CDT Sat Jun 24 2017/ AVIATION.../00Z TAF/ A rather diffuse frontal boundary seems to be meandering from near Del Rio to Waco eastward into central LA. Basically the gradient between mid 70 dewpoints to the south and mid 60 dewpoints to the north. Radar shows little if any convection over the area with a few new showers developing near KPSN along the front. Overall think that the boundary layer has been worked over and stabilized by today`s convection that re-development of convection will be a challenge. But then you glance at the latest HRRR runs and start to think otherwise. Possible that between 02-03Z convection could develop along the front with some outflows from KCLL to KCXO. For now there is no mention of convection but quite possible that amendments will be needed to account for new storms. Convection should stay north of KIAH but any outflows could re-generate convection give the moist airmass. Another scenario and is if convection does not develop, skies could clear out enough that with clam winds and wet grounds, fog could form over the area. SREF and even the GLAMP seem to suggest this possibility so added mention of lower visibility for a couple of hours. Tomorrow looks to be possibly a repeat of today with late morning convection forming and lasting into the afternoon. TAFs were adjusted an hour or two for convection forming in the late morning. Any MVFR/IFR conditions should improve during this time as well with day time heating. Overpeck PREV DISCUSSION... /ISSUED 328 PM CDT Sat Jun 24 2017/ DISCUSSION... Onshore winds have slowly become more easterly this afternoon, as a front pushes in from the north. Still continuing to monitor a few showers straggling along the coast and also in Washington County. Based on short time guidance, the best chance for possible showers to develop tonight would be in the northern counties of the CWA. Although, after the convection we saw earlier today thinking that conditions have stabilized, which would put a damper on the chance for wide spread development tonight. If this pans out, PoPs will need to be lowered for the overnight period. Conditions will definitely remain muggy, with forecast soundings keeping PWs between 2.0 to 2.25 inches through Sunday morning, and by late Sunday lowering to around 1.90 to 2.0 inches. With convective temperatures remaining in the low to mid 80s over the weekend and with such a saturated airmass lingering over SE TX, the ingredients are there for shower and thunderstorm development. Tomorrow, precip will most likely develop near leftover boundaries from today as well as along a weak sea breeze that could push onshore by late afternoon as we approach max temperatures. High temperatures for Sunday through Tuesday will reach up into the mid to upper 80s. There are also some higher values of vorticity that will move across the region in the upper levels, that could help to provide some lift first on Sunday afternoon and again late Tuesday. Still low confidence in the timing and location of exactly where this precip will end up over the next few days as most of the models lack agreement in the locations of development. SE TX remains centered between two upper level high pressure systems through next Friday. Expecting winds to remain out of the east until Wednesday, and then we will begin to see a return to onshore flow. PWs will be lower by Wednesday with PoPs also lowering, as an area of surface high pressure begins to move in from the east. Therefore, max temperatures will be on the rise by late next week, reaching into low 90s across much of SE TX. Hathaway MARINE... A weak outflow boundary may result in a few showers and thunderstorms across the nearshore waters this afternoon with a brief period of offshore flow possible in its wake. Otherwise, light to occasionally moderate east to southeast flow is expected across the coastal waters through mid-week and this will help keep tide levels 1-1.5 feet above normal over the next few days. In addition to elevated tides, east to southeast flow will help promote an increased risk for rip currents. A Beach Hazards Statement is in effect through tonight for these strong rip currents and additional Beach Hazards Statements may be needed at times through early next week for elevated tides producing wave run up along Bolivar Peninsula and increased rip current risk. Lee troughing over the High Plains will result in onshore flow strengthening to caution or possibly advisory criteria mid to late next week. Huffman && .PRELIMINARY POINT TEMPS/POPS... College Station (CLL) 73 87 72 88 72 / 50 50 30 40 20 Houston (IAH) 75 89 73 87 73 / 40 50 40 50 20 Galveston (GLS) 79 86 78 85 78 / 30 40 40 50 40 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...NONE. && $$ Discussion...40 Aviation/Marine...39
Area Forecast Discussion
National Weather Service Little Rock AR
949 PM CDT Sat Jun 24 2017 .UPDATE... HRRR has backed off on the small rain chances over the SE on the latest run or two but a few very weak returns are showing up on radar at this time. Temp/dew point spreads are in excess of 10 degrees where the echoes are showing up so most likely nothing more than sprinkles are hitting the ground. With weak short wave still expected to move through and into an area that is a little more moist, will keep the silent precip chances going. Remainder of the forecast also looks good with only a tweak or two needed. && .PREV DISCUSSION...(ISSUED 639 PM CDT Sat Jun 24 2017) AVIATION... VFR conditions are expected through the period as weak high pressure is located to the north. Only mid to high level moisture prevails with generally light winds. PREV DISCUSSION...(ISSUED 300 PM CDT Sat Jun 24 2017 ) SHORT TERM...Tonight through Monday The CDFNT that brought the active wx to AR on Fri/Fri night, was located well S of AR this aftn. NLY sfc winds behind the fnt contd to usher much drier air into the region, as noted by SFC dewpoints ranging fm the mid 50s to mid 60s. At the same time just 24 hours ago, we were looking at dewpoints in the mid 70s to arnd 80 degrees. Meanwhile, a good bit of mainly high lvl clouds have kept mid aftn readings generally in the 70s. Hi-Res model data does show some potential for small rain chcs late tngt ovr the SE half of the FA, as a weak upr short wv passes acrs the area. With much drier airmass in place in the low lvls, plan to not mention any POPS tngt ATTM, but wl let evening shift monitor later model data. Otherwise, still looking at a mostly dry fcst thru the PD sfc high pres prevails. We will see a NWLY flow aloft cont as well thanks to a broad upr trof ovr the ERN half of the nations, with an upr rdg persisting ovr the Rockies. Small chcs for convection wl return to the fcst ovr NRN AR later on Mon, as a weak upr impulse drops SEWD towards the state. Temps wl cont below seasonal norms the next few days, which is not often mentioned for AR in late June. LONG TERM...Monday Night through Saturday The extended period will start with high pressure at the surface and aloft over the region. This will bring dry conditions, mostly sunny skies with highs a bit below normal. On Wednesday, the surface high pressure is forecast to move east of AR, as a return south flow comes back to AR. Some weak upper energy is possible in northwestern AR areas, and with an approaching surface system in the plains, a slight chance of convection may develop. But at this time kept the chance of rain low due to uncertainty. On Thursday, a bit better chance of convection may be possible, as better upper short wave energy and improved south flow sets up into AR. The heating in the afternoon and early evening will be the best chances, but again only a 20 to 40 percent chance is forecast. Friday and into the weekend, models do show the best upper lift and a possible frontal system to sag closer to possibly into AR, and this would bring the best chance of convection. As mentioned, temperatures will start mild for this time of year, with lows in the 60s and highs in the 80s. A gradually warming trend and increase in humidity will be seen as the week continues. && .LZK Watches/Warnings/Advisories...NONE. && $$ 56
Area Forecast Discussion
National Weather Service Midland/Odessa TX
600 PM CDT Sat Jun 24 2017 .DISCUSSION...Please see Aviation discussion below. && .AVIATION...VFR conditions currently across all TAF locations. Short range ensemble forecasts are indicating that MVFR conditions will develop across all TAF sites overnight...most likely by 09Z. It`s possible that conditions could even become IFR for a brief period. Skies should become VFR by late Sunday morning. The high resolution HRRR is indc that convection is possible late Sunday morning at KMAF...however chances are too low to include in the TAF at this time. Strobin && .PREV DISCUSSION... /issued 156 PM CDT Sat Jun 24 2017/ DISCUSSION... Today tstms are most favored across the srn CWFA in closer proximity to the cold front and where upslope flow and modestly steep mid level LRs are noted. Otherwise this PM storms will form west of the continental divide in SW-W NM and track e-se per NW mid level flow with expected arrival in SE NM/Wrn CWFA around 06Z/Sunday and possibly PB after 09Z. Outflow boundaries and how much cooling occurs from Sun AM tstms will dictate the convective potential into Sun PM. Somewhat of a similar set-up Sunday night/Mon AM as storms move se across NM arriving in the NW CWFA 12Z-15Z Mon. Specifics of timing and location is difficult at best and forecast thru Sunday-Monday will look like a "smattering" of PoPs due to lack of clarification on features and source regions. Yet anther shrtwv trof in NW flow Monday night is possible. Even though that sounds simple enough that could be tied into shwrtv trof Mon AM of which timing in largely uncertain, but it would tend to impact n-e CWFA? High temps will remain below normal through Mon, but trend up. Meanwhile mid level theta-e ridge axis will begin to form Tue PM and along with daytime heating storm development across srn NM mtns are favored. Per NW steering flow they will have a good chance to move into SE NM late PM/evening. Said theta-e ridge will then favor tstms across the Trans Pecos mtns Wed-Thur, possibly drifting into the plains. According to ECMWF this pattern would persist into Sat. 85h temps are warmer on these 12Z runs that previous 24hrs, so probably hot across the wrn 1/3 of CWFA in the extended. && .PRELIMINARY POINT TEMPS/POPS... Big Spring 69 84 69 85 / 40 40 30 50 Carlsbad 70 89 69 89 / 50 30 60 20 Dryden 74 91 73 92 / 20 30 10 20 Fort Stockton 70 90 69 90 / 20 20 30 20 Guadalupe Pass 64 81 63 82 / 50 30 50 40 Hobbs 66 83 66 84 / 40 40 60 30 Marfa 64 86 62 85 / 20 20 30 20 Midland Intl Airport 69 86 69 87 / 40 30 30 50 Odessa 69 86 69 87 / 30 30 40 40 Wink 71 90 69 91 / 30 30 40 20 && .MAF WATCHES/WARNINGS/ADVISORIES... NM...None. TX...None. && $$ 33/67/33
Area Forecast Discussion
National Weather Service Reno NV
809 PM PDT Sat Jun 24 2017 .UPDATE... Isolated storms formed on our side of the Sierra Crest from Mono County to just south of Tahoe. Other storms fired just west of the crest from Sierra City to Lassen Park. Overall the storms have diminished, but a few showers remain west of the crest south of highway 50. Expect an overall quiet night, but the wave mentioned earlier, there will likely be some accas after sunrise north of Tahoe. The wave and upper level lapse rates over 7.5 C/km would support this. It doesn`t appear strong enough for any decent convection, but an isolated strike or two during the morning hours is not out of the question. This is handled well overall by the previous forecast so no updates are anticipated at this time. && .PREVIOUS DISCUSSION... /Issued 143 PM PDT Sat Jun 24 2017/ SYNOPSIS... Well above average temperatures continue through the weekend with some cooling by early next week. Isolated thunderstorms are possible near the Sierra this evening, spreading into parts of western Nevada and northeast California Sunday. Critical fire weather conditions are possible Monday as very dry air combines with gusty winds. After a brief cool down to near normal temperatures, a building ridge will bring another round of well above normal temperatures to the region starting Friday. Flooding will continue for the creeks in Mono County and portions of the Walker River. DISCUSSION... Isolated convection is possible into the early evening hours along the Sierra from Mono County north to around El Dorado County. The latest HRRR guidance is less robust of the east side of the Sierra...keeping much of the activity west of the crest. But the HRRR does hold out some slight chances for the Alpine County area. For the time being we will not reduce thunderstorm coverage...but we be a little over done. Attention turns to a mid level short wave lifting northeast across the region Sunday. Models have been trending down in terms in thunderstorm coverage with this feature. Timing is critical as a morning passage would tend toward less coverage overall. Right now it appears the best chance for increased coverage will be north of I-80 and west of a line from Cedarville to Gerlach. A potential vorticity maximum will be lifting across northeast California by late afternoon...but this appears to be the only mid/upper level support. Lapse rates aloft are not impressive and there is little in the way of jet support. While the convection should be rooted in a deep...well mixed boundary layer...the lack of upper level support will limit organization and coverage. Still...with increasing instability it is not out of the realm of possibility that we will see early development and continual cycling of storms from late morning into the afternoon. Any storms that develop would be moving fast enough to limit precipitation potential and produce dry lightning strikes. Showers linger into late Sunday night and early Monday morning over the far north. Drier air moves into the region and breezy winds develop Monday and Tuesday. Monday looks like the day with the best potential for critical fire weather conditions. See the Fire Weather discussion for more details. In the wake of the short wave trough...heights fall and temperatures Monday and Tuesday will drop back to just slightly above normal. This will slow snowmelt a bit in the higher elevations. Another trough will slide toward the region from the northwest Wednesday. This trough should bring mainly an increase in clouds as low level moisture is lacking for showers. Northwest flow aloft and low northeast develops in its wake Thursday. By Friday a ridge starts to build back into the region. This will bring a return to well above normal temperatures and possibly enough instability for isolated convection along the Sierra. For now we will leave mention of thunderstorms out of the forecast for Friday and Saturday...but they may need to be added in a few days. AVIATION... Isolated storms along the Sierra should be the only aviation concern for the first 12 hours of the forecast. A mid level trough of low pressure lifting northeast across the region Sunday will bring an increase in coverage for storms. The best chance for storms is across northeast California and far western Nevada...but we could see isolated storms all along the Sierra. As the trough lifts out late Sunday night a few showers will linger north of Susanville. Then...breezy winds will develop for Monday with surface gusts approaching 30-35 kts in many locations. Breezy continues continue into Tuesday...but the gusts will be a little less than Monday. FIRE WEATHER... Temperatures have warmed into the upper 90s with low 100s still likely for the daily high for many locations in western Nevada today. Recoveries were moderate to good in the Sierra last night with poor to moderate for western Nevada. With temperatures running warmer today, expect slightly poorer recoveries overnight into Sunday which will heat back to the upper 90s to low 100s again. Meanwhile, towering cumulus and a few thunderstorms have formed in the Sierra and along the Long Valley Caldera rim in southern Mono County. Expect thunderstorms to continue to form along outflow boundaries and higher terrain of the Sierra mainly south of the Tahoe Basin through the rest of the afternoon. Gusts in valleys could be strong with slight potential for a stray dry lightning strike. Main changes to the ongoing forecast have been to trim thunderstorm chances down slightly for Sunday as models continue to show an earlier passage of a destabilizing upper wave. With this wave passing earlier Sunday morning, instability aloft will be un- phased from highest surface instability. Still, chances of isolated thunderstorms cover a much larger area than recent activity. Any storms that form will be capable of producing strong gusts and dry lightning strikes, especially if they move over western Nevada valley locations. Just a few strikes along the Sierra Front would likely be enough to allow for new fire starts since dried grasses are nearly continuous. Finally, an upper low moves into northern California Monday increasing winds across the region. Expect critical fire weather conditions for western Nevada as winds gust around 35mph. As such, a fire weather watch remains in effect for portions of western Nevada including the Sierra Front, northern Lyon County, and Churchill/Pershing Counties. Winds drop off below critical thresholds Tuesday and Wednesday, but would still be able to drive any grass fires that may occur. Grasses east of Highway 395 in California, mainly in Lassen County, have mostly cured and could propagate fire. While this zone is not technically fire ready, it`s something to prepare for. It should also be noted that sagebrush in western Nevada valleys is beginning to show signs that it is becoming dry enough to carry fire; it may not contribute to explosive fire growth, but it will be available to burn. Boyd && .REV Watches/Warnings/Advisories... NV...Fire Weather Watch from Monday afternoon through Monday evening NVZ450-453. CA...None. && $$ For more information from the National Weather Service visit... http://weather.gov/reno
Area Forecast Discussion
National Weather Service Shreveport LA
1022 PM CDT Sat Jun 24 2017 .DISCUSSION... The evening sfc analysis indicated that our true weak sfc front extends from Cntrl MS WNW to near the I-29 corridor of N LA/E TX to N of the DFW Metroplex crossing the Red River into far SW OK. This matches up well with the H850 frontal position, with drier air noted via the sfc theta-e and elevated cigs near and N of these bndrys, with the air mass farther S having been modified since the broad mesoscale bndry from the AR MCS Friday moving through E TX/Ncntrl LA early this morning. Meanwhile, the upper air analysis still depicts a weak shear axis in place across Scntrl and Deep E TX NE into Ncntrl LA, which has helped focus sct convection this evening over these areas. The short term progs remain in agreement with this shear axis drifting a tad SE overnight, with the potential for weak convergence along the H850-700 trough to result in sct convective redevelopment overnight over Deep E TX/Srn sections of Ncntrl LA. The HRRR remains rather bullish in its development after 06Z especially over Ncntrl LA, but better instability current resides over Deep E TX and along the lower Toledo Bend Country of Wcntrl LA, where SBCapes of 1000-1500 J/Kg remains in place. With the current convection backbuilding along Wwd moving outflow bndrys across Shelby/Nrn San Augustine/Ern Angelina Counties attm, its feasible that an uptick in convection here given the weak mid level convergent axis may allow for sct areas of -SHRA/-TSRA to spill E across our Srn most N LA Parishes. However, not expecting QPF amounts as seen the last few days given the lack of deep lyr forcing. For the update, did tweak sky conditions to mostly cloudy, even across NE TX/SE OK/SW AR, as additional AC develops and spreads SE overnight as the cirrus shield thins. Also tapered pops back a tad along the Srn fringes of the drier air near the I-20 corridor, resulting in a few areas having slight chance pops removed for Sunday. Did maintain mid and high chance pops for Deep E TX/Srn sections of Ncntrl LA given even the 00Z NAM suggesting additional sct development after 06Z for these areas. Also made some minor upward tweaks to min temps as well, as the increasing AC and lack of cool/dry advection should not allow temps to cool as much as previously advertised, especially over SE OK/Nrn sections of SW AR. Otherwise, the remainder of the forecast is in good shape. Zone update already out...grids will be available shortly. 15 && .PREV DISCUSSION... /issued 737 PM CDT Sat Jun 24 2017/ AVIATION... For the ArkLaTex, a weak fropa has convection S and E of all terminals. Sfc winds are NE 5KT for the most part. There is a tut low lifting out of the W Gulf that is interesting and modeled to lift current convection toward KMLU, but TSTMS are gusting out and propagating the cluster toward KSHV. We will monitor as setting sun may not see it`s demise with low lifting NE. For now all sites rain free for the evening. Outlook is for high pressure to win out bolstering the front to move farther S and W for a few days. /24/ && .PRELIMINARY POINT TEMPS/POPS... SHV 70 86 67 88 / 20 20 10 10 MLU 69 86 65 88 / 20 20 10 10 DEQ 64 87 64 86 / 10 10 10 10 TXK 66 86 65 86 / 10 10 10 10 ELD 65 86 63 87 / 10 10 10 10 TYR 70 85 68 87 / 20 20 20 20 GGG 69 86 67 88 / 20 20 10 20 LFK 73 85 70 88 / 50 40 20 20 && .SHV WATCHES/WARNINGS/ADVISORIES... AR...None. LA...None. OK...None. TX...None. && $$ 15
Area Forecast Discussion
National Weather Service Las Vegas NV
845 PM PDT Sat Jun 24 2017 .SYNOPSIS...The prolonged heat wave over the region will finally break early this coming week as a weak weather system moves across the western states. This system will result in enhanced winds early this week will increase the fire danger. Isolated thunderstorms will remain possible over the Sierra through Sunday. && .UPDATE...An isolated thunderstorm south of Panamint Springs is on the decrease currently. HRRR suggests isolated showers or thunderstorms possible up to midnight across parts of Inyo and Esmeralda County. Convection being driven by an upper level disturbance moving north through central California. NAM shows more instability across southern Mohave County by midday Sunday before more stable air spreads in during the late afternoon/early evening tomorrow. Will await additional model data before committing adding a slight chance to the Hualapai Mtns Sunday. Update for the rest of tonight is out. && .PREV DISCUSSION...139 PM PDT Sat Jun 24 2017 .SHORT TERM...Today through Monday. As expected, isolated to scattered clouds have developed today along with a few showers/thunderstorms over the southern Sierra. Little impact is expected from these showers outside of perhaps some gusty winds. Elsewhere, temperatures as of this writing were running 0-2 degrees higher than 24 hours ago, right on track with the current forecast. The forecast for Sunday also remains on track with most areas seeing 2-3 degrees of cooling. The chances for showers/isolated thunderstorms will remain over the southern Sierra through Sunday as well. Finally, I did add a mention of smoke to the far east- central portions of the forecast area (Mesquite/Colorado City) for tonight to account for any smoke drift from the Brian Head fire in Utah. For Monday, the latest guidance has come in slightly cooler than the previous forecast. As a result I lowered high temperatures around a degree, taking Las Vegas down to 109. It`s going to be a race to the finish for the record number of consecutive 110F+ days in Las Vegas. The current record stands at 10 day and Monday would be the consecutive 10th day of this heat wave. I made no changes to the excessive heat product as 109 vs 110 will provide little relief after such a stretch of hot conditions. Monday will also see an uptick in wind speeds across the region, with widespread gusts of 20-30 mph, and isolated gusts around 35 mph. .LONG TERM...Tuesday through Friday. By Tuesday, the ridge over the southwest will be suppressed a bit as a shortwave moves across the northern Great Basin. Suppression of the ridge will continue through much of the work week as a trough over Alberta, Canada will deepen and drape over much of the western CONUS. Temperatures will see a 3-5 degrees drop by Tue with highs only a few degrees above normals by mid week. Breezy southwest winds are expected each afternoon with wind speeds 10 to 20 mph with gusts up to 25 mph. Wednesday afternoon, both the GFS and ECMWF are showing a tight gradient over much of central Mohave County. This will cause some gusty southwest winds up to 30 mph Wed afternoon. Otherwise, dry and mostly clear conditions through the work week. && .FIRE WEATHER...The prolonged heat wave over the region will finally break early this coming week as a weak weather system moves across the western states. This system will result in enhanced winds early this week which, when combined with dry and warm conditions, will increase the threat of critical fire conditions. Winds look to peak in most areas on Monday, with fairly widespread gusts of 20-30 mph, and isolated gusts around 35 mph. Isolated thunderstorms will remain possible over the Sierra through Sunday. && .CLIMATE...Near record to record high temperatures will be possible today and Sunday. The current record of consecutive days above 110 degrees in Las Vegas is 10 days (1961), and for 115 degrees, 4 days (2005). Las Vegas, NV Climate Forecast High Temps (F) Daily Record Max Temps (F) SAT (6/24): 114 113 (1961) SUN (6/25): 112 115 (1970) Forecast low Temps (F) Daily Record High Min Temps (F) SUN (6/25): 88 86 (1974) && .AVIATION...For McCarran...Light southwest to west is expected this evening with less than 8kts expected. Hot temperatures will continue through Monday with afternoon highs at or above 110 degrees. Scattered high clouds will be observed today however VFR conditions will prevail. Typical overnight trends are expected, with winds coming back up again late Sunday morning out of the northeast, but remaining below 10kts. For the rest of southern Nevada, northwest Arizona and southeast California...Isolated thunderstorms will be possible over the southern Sierra this afternoon with brief gusty winds likely near any storms. Gusty west winds 25-30 knots will develop across the western Mojave Desert late this afternoon and evening. Hot temperatures will continue across the Mojave Desert areas through the weekend with afternoon highs at or above 110 degrees. Scattered high clouds and VFR conditions expected. && .HYDROLOGY...Observed flows on unregulated creeks, specifically Independence Creek, Big Pine Creek and Rock Creek indicated flows have decreased slightly since their peak flows occurred earlier this week. Creeks, streams and rivers along the eastern Sierra slopes of Inyo County as well as the Owens Valley will be flowing high and fast into at least early next week. Minor flooding could occur near creeks as well as a few low water crossings on some roadways. Remember, never drive through flooded roadways or around barricades. Also, pastureland or farmland adjacent to creeks, streams or rivers could experience areas of standing water. && .SPOTTER INFORMATION STATEMENT...Spotters are encouraged to report any significant weather or impacts according to standard operating procedures. && $$ Update...Pierce SHORT TERM...Wolcott LONG TERM....Kryston AVIATION.....Allen For more forecast information...see us on our webpage: http://weather.gov/lasvegas or follow us on Facebook and Twitter