Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 07/25/18

Area Forecast Discussion
National Weather Service Bismarck ND
942 PM CDT Tue Jul 24 2018 .UPDATE... Issued at 925 PM CDT Tue Jul 24 2018 Monitoring the evolution of two alto-cumulus fields which continue to show deeper elevated convection per radar trends through 0240 UTC. The broader field was located from along US- Highway 2 through Lake Sakakawea, with a second field from near Beach through Dickinson. Do expect convection to continue to slowly intensify over the next 2 to 3 hours with increasing forcing. The 00 UTC Hi-Res ARW/NMM and NAM NEST are in, as well as the HRRR through the 01 UTC iteration, and continue to signal the potential for a line of organized convection. This is most notable within the rather high updraft helicity tracks. Based on observed and CAM trends, confidence has increased somewhat to enhance expected threats to damaging winds to near 70 mph and large hail to half dollar size. UPDATE Issued at 702 PM CDT Tue Jul 24 2018 Severe convective potential overnight, beginning around the 05-06 UTC timeframe, highlights the near term forecast. The operational and the ESRL experimental HRRR through their 21-23 UTC iterations consistently depict a line of elevated convection potentially developing around the 05-06 UTC timeframe around North Dakota Highway 200. This general depiction is also seen in the 18 UTC NAM NEST, and the 12 UTC Hi-Res Window ARW and NMM runs from 12 UTC. This initiation would be in response to strengthening low level warm air advection with a low level jet with convergence along a stalling warm front. Additional forcing would be added by the mid level jet, which would also lead to strong effective deep layer shear around 45-50kts. Overall, elevated instability is modest, around 600-1200 j/kg. A high shear/modest CAPE parameter space with shear vectors with a large component parallel to the elevated boundary would support the potential for a quick upscale growth into a few organized line segments that would propagate southeast through the overnight. Regarding threats, despite the strong deep layer shear, rather low moisture levels may limit the hail threat to not much more than a marginal severe threat. Damaging wind is a bit more uncertain, and could conditionally pose a higher risk. Storms that form would be high based above a deep low level dry layer that would be favorable for damaging winds to the surface, especially with any bowing segments. What adds uncertainty though is the stabilization of the boundary layer quickly after sunset with the dry air, and how that will impact momentum transfer to the surface. Again, the damaging wind threat is higher than the hail threat, although somewhat conditional. This has been coordinated with SPC as input into their upcoming Day 1 update. && .SHORT TERM...(This evening through Wednesday) Issued at 316 PM CDT Tue Jul 24 2018 The main forecast concern for the short term is the potential for strong to severe thunderstorms this evening and tonight. Scattered showers and isolated thunderstorms have developed along an area of weak low-level convergence across northwest North Dakota this afternoon. This activity is not expected to become severe, as it is moving over a fairly stable air mass. A lack of strong forcing mechanisms and a subtle cap will likely prevent convective initiation over a modestly unstable airmass across central and southern North Dakota through the afternoon. Later this evening, low to mid-level frontogenesis will increase in response to a shortwave trough moving down from Saskatchewan. Convection is forecast to develop along the strengthening boundary later this evening, and may hold off until closer to midnight as recent runs of the HRRR have been suggesting. MUCAPE will be limited to 500-1500 J/kg, but bulk effective shear exceeding 50 kts will be sufficient for strong to severe storms. Shear vectors oriented parallel to the boundary should promote quick, upscale growth into multicell linear clusters. This, combined with a relatively dry moisture profile, means damaging wind gusts will be the primary threat, though marginally severe hail cannot be ruled out. Despite the overall lack of atmospheric moisture, will need to watch for training storms along the boundary. Thunderstorms will move off to the south and east Wednesday morning as the upper-level shortwave moves through the state. Cyclonic flow aloft combined with steep low-level lapse rates may produce isolated showers and storms Wednesday afternoon, though moisture will be limited. This potential is not high enough to include a slight chance PoP at this time. Look for breezy conditions Wednesday afternoon, with north-northwesterly winds around 15-25 mph, possibly gusting to 35 mph across the north. .LONG TERM...(Wednesday night through Tuesday) Issued at 316 PM CDT Tue Jul 24 2018 Cool and dry Canadian high pressure will then build into the Northern Plains Wednesday night through Friday. Under this air mass, expect temperatures 5 to 15 degrees below normal, with highs in the 70s and lows in the upper 40s to mid 50s. A return to a more active pattern is suggested by model guidance for the weekend into early next week. The general synoptic pattern calls for an upper-level high over the Desert Southwest and longwave troughing across the Great Lakes region. In between the ridge and trough, various disturbances are forecast to move across the Northern Plains. The influence of height rises from the upper-level high should return temperatures to near normal. && .AVIATION...(For the 00Z TAFS through 00Z Wednesday evening) Issued at 925 PM CDT Tue Jul 24 2018 A line of thunderstorms developing as of 0240 UTC south of KISN/KMOT will continue to intensify and increase in coverage as they move southeast through the overnight. The greatest impacts are expected to KBIS/KJMS. Damaging winds and large hail are possible. See TAFs for expected timing and impacts. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...PA SHORT TERM...Hollan LONG TERM...Hollan AVIATION...PA
Area Forecast Discussion
National Weather Service Cheyenne WY
629 PM MDT Tue Jul 24 2018 .UPDATE... Issued at 626 PM MDT Tue Jul 24 2018 Isolated thunderstorms and shower activity ongoing near the Wyoming/Nebraska border this evening. Increased POP across the southern Nebraska panhandle since the activity has been a bit more pronounced just west of this area. Expected thunderstorms to continue over the next few hours before ending prior to 10 PM. Stronger thunderstorms may linger across the far northern NE panhandle past midnight tonight. && .SHORT TERM...(This evening through Wednesday) Issued at 230 PM MDT Tue Jul 24 2018 Currently...Surface front analyzed over southern Montana this afternoon. Has not shown much southerly movement over the past 6 hours. Surface high pressure over central Colorado. Latest radar imagery showing some light cells developing over the Laramie Range, just south of Douglas drifting southeasterly and dying once they come off the Laramie Range. SPC mesoanalysis surface based CAPES ranging from 2500 J/KG down here near Cheyenne to 4000 J/KG across northern Niobrara County. Shear almost non existent over southeast Wyoming with 45-50kts from Lusk into most of the Panhandle. Using the latest HRRR guidance as the main tool on this afternoons forecast. Shows a few cells developing over the Laramie Range and drifting off to the east southeast after 22Z. Guidance shows these storms intensifying as they get into the better CAPE and shear across extreme southeastern Wyoming and into the Panhandle. Pretty strong to severe cell forecast just north of Cheyenne at 23Z that bows out over Kimball County around 01Z. So kept severe wording in the forecast for this afternoon and early evening. Front continues to drift south into the CWFA this evening into tomorrow. By 09Z tonight, front forecast to be over Lusk and Douglas. By 18Z, this front is forecast to be laying along the east slopes of the Laramie Range. Do think the Thunderbirds flight in the morning will be ok as low level winds will still be out of the northwest before turning northeast during the afternoon. By afternoon though, low level winds shift northeast and am expecting an increase in low level cloudiness. All PoP guidance showing widespread precipitation developing late afternoon into the evening hours. Afternoon CAPE expected near 1800 to 2000 J/KG tomorrow afternoon with PWATs of 1 to 1.25 inches. Heavy rain looking likely for the Cheyenne area during the afternoon and evening hours and have increased PoPs to around 80 percent. Fortunately, storm motions are still fairly fast from northwest to southeast at 20-25kts. If storm motions come in slower, we will be dealing with Flash Flood concerns. Later shifts may want to consider a Flash Flood Watch for Wednesday afternoon and evening. .LONG TERM...(Wednesday night through Tuesday) Issued at 230 PM MDT Tue Jul 24 2018 A rather wet forecast expected through Sunday as that stalled out front interacts with the monsoonal moisture. Have maintained high PoPs each afternoon/evening through Sunday. Will be dealing with heavy rain potential and potential for flash flooding for areas east of the Laramie Range each day. Finally see a drying out after Sunday night as Four Corners high builds northwest into northern Nevada and northern Utah. && .AVIATION...(For the 00Z TAFS through Wednesday afternoon) Thunderstorms will continue over far eastern Wyoming and western Nebraska through 05z late this evening. Kept VCTS over the western NE terminals, but generally expect VFR conditions to prevail with gusty outflow winds from thunderstorms. Will also keep an eye on possible fog development tonight where significant rain does fall in addition to a cool front moving southward across the eastern plains. As of right now, confidence is too low on where/when any fog will form. && .FIRE WEATHER... Issued at 300 PM MDT Tue Jul 24 2018 Minimal fire weather concerns through Sunday as monsoonal moisture remains over the area. Looking at above critical afternoon humidity with good to excellent humidity recoveries overnight. Also looking at fairly widespread wetting rains beginning Wednesday as a slow moving cold front moves into the area from the north and stalls along the Laramie Range. This front and the mountains will serve as a focusing mechanism for showers and thunderstorms. Bigger hazard will be flash flooding on the Badger Creek burn scar that we will need to watch closely. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...None. NE...None. && $$ UPDATE...TJT SHORT TERM...GCC LONG TERM...GCC AVIATION...TJT FIRE WEATHER...GCC
Area Forecast Discussion
National Weather Service Grand Forks ND
1006 PM CDT Tue Jul 24 2018 .UPDATE... Issued at 1005 PM CDT Tue Jul 24 2018 Additional adjustments made to near term PoP/Wx to account for current trends with activity developing across north central ND. This is generally matching HRRR (though a touch early and more extensive to the north than HRRR originally had). Expecting cluster of storms to increase in coverage and transition southeast into our western CWA late this evening and continue thorugh the early morning Wed (matching previous trends). Severe threat still appears to be possible with strong shear and elevated CAPE 1500-3000 J/KG. I`m keeping messaging at 60 mph/1" hail for now for stronger activity late tonight, though I could see a potential for stronger wind if stable low levels are too much of a hindrance. UPDATE Issued at 558 PM CDT Tue Jul 24 2018 Adjusted near term PoPs/Sky to match radar/satellite trends showing isolated to scattered showers over our northwest CWA ahead of weak mid level impulse. Most activity is probably just sprinkles, but there are a few pockets of 40dbz. There may be enough instabiility for a few weak thunderstorms as well, but so far trends seem to favor showers early on. && .SHORT TERM...(This evening through Wednesday) Issued at 248 PM CDT Tue Jul 24 2018 Afternoon satellite imagery shows an upper level low positioned across south central Canada with a secondary lobe of vorticity just to its west. With the passage of the main upper level trough over the region this morning and day time heating allowing for low level adiabatic lapse rates, strong mid level winds have been mixing down to the surface and allowing for wind gusts up to the 20 to 25 knot range across far northeast ND and northwest MN. These winds will continue through sun down before gradually diminishing. The secondary lobe of vorticity is expected to push southeastward into the north central CONUS overnight tonight. Ahead of this, differential vorticity advection will allow for a few showers and thunderstorms across central ND. Most CAMs suggest low to moderate elevated instability will be in place across the region overnight tonight, and coupled with strong bulk wind shear, will allow for thunderstorm chances, a few of which may be strong to severe, though widespread severe coverage is not expected. Storms may also be focused along a weak surface boundary draped east to west just north of the I-94 corridor later this evening, though surface forcing will likely be weak. Showers and storms that do develop will propagate southeastward into the southern Red River Valley by Wednesday morning. Strong mid level cold air advection on the back side of the surface low associated with the vort lobe/upper level low may allow for some shallow instability tomorrow afternoon (granted cloud cover does not prevent adequate daytime heating). This instability may be realized in the form of shallow convective showers scattered across the region. However, confidence in this scenario is low at this time. .LONG TERM...(Wednesday night through Tuesday) Issued at 248 PM CDT Tue Jul 24 2018 The FA remains in northwest flow at 500mb for Wednesday into Thursday, as the 500mb low tracks through southern Ontario. Some lingering showers are possible Wednesday night, but mainly over northwest Minnesota. A cold pool aloft may lead to some instability showers on Thursday, and again mainly over northwest Minnesota. Highs Thursday remain cool, then begin a slight warming trend by Friday. Highs look to get back closer to normal for the Saturday through Tuesday time frame. There is some short wave energy over the FA for the weekend, so there could be some scattered showers and storms around. At this point, it looks pretty minimal, but will have to keep an eye on it. Ridging pushes back in by Monday and Tuesday, which would favor a dry period. && .AVIATION...(For the 00Z TAFS through 00Z Wednesday evening) Issued at 635 PM CDT Tue Jul 24 2018 VFR conditions should prevail, with main concern focused on possible shower/thunderstorms development across ND which could move into NW MN. Currently best chance will be across southeast ND with impacts expected at KFAR. There is less confidence further north and east, but VCTS still appeared warranted at KDVL and KGFK based on current model trends. Wed morning MVFR stratus may develop into NW MN, but this appears to remain north of KTVF/KBJI, but will need to be monitored. Winds should become light and variable increasing from the northwest late in the TAF period. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...None. MN...None. && $$ UPDATE...DJR SHORT TERM...AM LONG TERM...Godon AVIATION...DJR
National Weather Service Jackson KY
1050 PM EDT Tue Jul 24 2018 .UPDATE... Issued at 1050 PM EDT TUE JUL 24 2018 Did a quick update to drop the thunder from the grids, zones, and HWO. Also added in the latest T/Td obs and trends. The updated grids have been sent to the NDFD and web servers. UPDATE Issued at 730 PM EDT TUE JUL 24 2018 23z sfc analysis shows a broad area of low pressure over eastern Kentucky beneath a filling and slowly departing upper level low. This has sprung up convection mainly just east of the JKL CWA with a few pin prick showers showing up across the CWA leaving little more than a trace of rain behind. The CAMs and HRRR suggest that the far eastern part of the area still may see some showers and thunderstorms through the rest of the evening. Will continue this idea in the grids. Have also beefed up the fog in a hybrid situation of stratus build down in the east and radiational cooling in the west could result in patchy dense fog for a time in the valleys west and mainly on the ridges east. Will update the HWO to add that concern in for the overnight and also run a new set of zones to not limit the fog to the valleys. An SPS may be needed later this evening or early overnight - similar to last night. Currently under partly to mostly cloudy skies temperatures generally in the mid to upper 70s while dewpoints run in the mid 60s to lower 70s across eastern Kentucky. Winds remain mainly light from the north. Did also add in the latest obs and trends for the T/Td grids with this updated. The freshened grids have been sent to the NDFD and web servers. Look for an updated set of zones and HWO to follow shortly. && .SHORT TERM...(This evening through Wednesday night) Issued at 346 PM EDT TUE JUL 24 2018 Showers have been sparse thus far as extensive low stratus has put a damper on instability across eastern Kentucky. Local lift has also been somewhat dampened as an upper low spins across the southern Appalachians, placing the brunt of its associated lift east of the Commonwealth. Water vapor continues to show a tight mid-upper level moisture gradient across central into portions of eastern Kentucky, with drier air attempting to nose eastward on the backside of the upper circulation. Light northwest surface winds and the nearby presence of cyclonic flow are enough to warrant isolated to scattered showers across the higher terrain of eastern and southeastern Kentucky with the lack of lift and drier air, evidenced by dewpoints in the low-mid 60s, winning out across much of the Bluegrass and Lake Cumberland regions. Have confined thunder to a slight chance mention given the dampened instability and more cellular convection embedded in the greater/deeper moisture and more appreciable forcing across the Virginias and Carolinas. What precipitation can develop will diminish this evening with sunset, leading to mostly cloudy conditions overnight. Stratus build- down will impact local ridges, while areas of river valley fog materialize underneath any breaks in the clouds. This again will be more prevalent east of the Bluegrass region and Interstate 75 corridor where enhanced moisture resides. Fog will mix out as cloud ceilings gradually lift by mid Wednesday morning ahead of an approaching cool front. This front will help to spark afternoon convection across the higher terrain as upslope flow interacts with lingering moisture. Drier and somewhat cooler air will move in by Wednesday evening behind the front as surface ridging builds in. A ridge/valley temperature split will be in the offing as ridges cool into the mid 60s with valleys dipping into the low 60s Thursday morning. .LONG TERM...(Thursday through Tuesday) Issued at 346 PM EDT TUE JUL 24 2018 A series of weather systems will bring chances of showers and storms to eastern Kentucky on Friday, and again from Saturday night through Monday night. The best chance for rain on each of these days should be during the afternoon and early evening hours. Temperatures should run generally below normal, with daily highs in the low to mid 80s and nightly lows in the low to mid 60s. && .AVIATION...(For the 00Z TAFS through 00Z Wednesday evening) ISSUED AT 750 PM EDT TUE JUL 24 2018 SHRA/TSRA chances continue to be mainly east of the Commonwealth, with only isolated to perhaps scattered coverage toward KSJS/KPBX and along the West Virginia/Virginia state borders. Look for low ceilings and reduced visibilities taking place again tonight into Wednesday morning - particularly over the eastern TAF sites. Confidence is slightly better regarding low ceilings and stratus build-down, with fog and visibility reductions more susceptible to any clearing that can occur. Have portrayed a stratus build-down scenario in the eastern TAFs while going with a radiational cooling valley fog situation further west. Both these results should be IFR and LIFR CIG/VIS for the TAF sites late tonight and into dawn Wednesday. This will all mix out by mid morning with just a small chance for a shower at SJS around midday. Calm to light winds will increase to around 5 knots out of the northwest with arrival of a cool front on Wednesday. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...GREIF SHORT TERM...GUSEMAN LONG TERM...AR AVIATION...GUSEMAN/GREIF
Area Forecast Discussion
National Weather Service Midland/Odessa TX
646 PM CDT Tue Jul 24 2018 .DISCUSSION... && .AVIATION... VFR with a swath of mid level clouds currently sagging south across the area. Otherwise E/NE wind will become more SE Wednesday. && .PREV DISCUSSION... /issued 219 PM CDT Tue Jul 24 2018/ DISCUSSION...As of 2:00 pm CDT Tuesday...Hey what do you know!! It`s "cooler" out there...95 at MAF instead of the oppressive 100-105 we have been seeing for the past five days. Normal for today is 95. Sfc obs show the "cold" front has made it across the Rio Grande. A band of clouds seen on vis imagery...based on cloud top temps probably relatively flat cu are moving south thru the northern PB. Based on earlier vis imagery it`s partially associated with a MCV that moved south thru eastern NM this morning. Ridge centered smack dab on the NM/AZ border will continue to slowly retrograde thru the end of the week and become centered over SOCAL by Friday aftn. This will allow weak impulses to drop south thru the CWA and keep temps in relative check (near normal which is 95 for MAF). As for rain chances...the NAM and ECMWF are a little more bullish than the GFS. The hi-res RAP13 and HRRR are not enthusiastic about pop chances for tonight so they have been trimmed a bit farther west. The best chances remain along the NM Guadalupe/TX Davis mtns and adjacent plains. The impulse dropping south Thursday night could spread storm activity as far east as the central PB. The ridge expands a bit east over the weekend before moving north and becoming centered over the NV/UT/AZ triple point on Sunday. H85 temps increase and with dry weather expected temps will warm to near the century mark once again across the area with temps up to 105 in the Trans Pecos/Rio Grande. Yay (not really). As the ridge edges to the northwest early next week a trof will deepen as it drops southeast out of southern Canada. This will drag a cold front across the CWA early next week (Mon/Tue) with the GFS a bit faster. Storm chances will increase with temps cooling off to the mid 80s to lower 90s (per the GFS)...or the mid to upper 90s per the ECMWF. Let`s hope the GFS pans out as it would be nice to get some rain and cooler temps. Stay tuned! Strobin && .PRELIMINARY POINT TEMPS/POPS... Big Spring 75 96 76 96 / 0 0 0 10 Carlsbad 75 98 75 98 / 20 10 20 20 Dryden 81 98 77 97 / 20 10 0 10 Fort Stockton 77 96 76 95 / 10 10 10 20 Guadalupe Pass 71 89 70 88 / 30 10 20 20 Hobbs 72 93 72 93 / 20 10 20 40 Marfa 68 88 67 88 / 30 30 20 30 Midland Intl Airport 74 96 75 96 / 10 0 10 10 Odessa 74 96 75 96 / 10 10 10 10 Wink 77 98 76 97 / 10 10 20 20 && .MAF WATCHES/WARNINGS/ADVISORIES... NM...None. TX...None. && $$
Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
1020 PM CDT Tue Jul 24 2018 .UPDATE... Issued at 1020 PM Tue Jul 24 2018 Updated to include 06Z aviation discussion below. && .SHORT TERM...(This evening through Wednesday night) Issued at 300 PM CDT Tue Jul 24 2018 Another pleasant day today with dry air and seasonably normal temperatures. The clear skies will continue for much of the night, but a sharpening mid level trough will be entering the northern Rockies late tonight while a LLJ strengthens over the Plains. Showers and thunderstorms will develop after midnight in the vicinity of Bismarck and then build southward along a cold front into South Dakota. The northern main cluster of thunderstorms will track down I-94 for the rest of the night and push into central and western Minnesota near dawn, reaching eastern Minnesota by mid morning in a weakening state. It seems unlikely this activity will be severe, but certainly some gusty winds and heavy rainfall may accompany the leading edge of this decaying MCS. There is rather low confidence how the rest of the day will play out. A sharpening mid level trough will be entering western Minnesota during the middle afternoon which will lead to strengthening 500 mb flow around 50 kts near the base of the trough. Given enough instability in the presence of 40 to 50 kt effective shear and sufficient convergence on the approaching cold front, a mix of supercells and clusters would be expected with all severe weather hazards possible. However, considerable cloud cover from earlier convection may prevent appreciable instability from developing in the afternoon and outflows/cold pool from said earlier day convection could leave low level flow too weak for tornadoes. HREF does indicate about a 50 percent chance for 1500 J/kg of SBCAPE. This may be enough, but given the shear would prefer to see at least 2000 J/kg. Far southern Minnesota southwestward stands the best chance for missing the morning round, which is where SPC has introduced a Slight Risk. CAMs seem just as unenthused about redevelopment in the afternoon, but there are a few stronger cores in the HRRR and the ARW along the cold front. The potential is there for severe weather, but it will take some work that very few days this year have been able to achieve. The cold front will clear the CWA quickly during the evening with the risk for storms dropping off shortly after sunset across southern MN and western WI. .LONG TERM...(Thursday through Tuesday) Issued at 315 PM CDT Tue Jul 24 2018 Thursday will be the coolest in the next 7 days as the core of the cool air mass moves overhead. The anomalous upper low that is responsible for the cooler conditions will continue to slowly rotate east-southeast across the Great Lakes late this week, and begin to modify and lift over southeast Canada this weekend, and into next week. Some instability showers or storms will be possible Thursday afternoon over west central Wisconsin as the system begins to modify and move eastward into southeast Canada. Overall, it should be a dry and comfortable this weekend with little wind as high pressure dominates. Weather models continue to support a quasi-zonal flow aloft next week. Some differences are noted with the next frontal boundary by midweek, but generally, temperatures will recover to 80s, with humidity levels slowly building. && .AVIATION...(For the 06Z TAFS through 06Z Wednesday night) Issued at 1020 PM CDT Tue Jul 24 2018 Didn`t make any significant changes from 00Z forecast package, with reasoning similar to before. Some convection has started to develop upstream over North Dakota, so tweaked timing with morning convection in our area based on extrapolation of that activity and latest guidance from the HRRR and HopWRF solutions. Otherwise, stuck fairly close to previous timing and ceiling/visibility values. KMSP...Main uncertainties are with timing of activity on Thursday, and the degree to which ceilings and visibilities will be impacted. /OUTLOOK FOR KMSP/ Wednesday night...VFR. Northwest wind 5 to 10 kt. Thursday...VFR. Northwest wind 5 to 15 kt. Thursday night...VFR. Northwest wind 5 kt or less. Friday...VFR. Northwest wind around 5 kt. Friday night...VFR. Variable wind less than 5 kt. Saturday...VFR. Variable wind 5 kt or less. && .MPX WATCHES/WARNINGS/ADVISORIES... WI...None. MN...None. && $$ UPDATE... SHORT TERM...BORGHOFF LONG TERM...JLT AVIATION...
Area Forecast Discussion
National Weather Service Pittsburgh PA
952 PM EDT Tue Jul 24 2018 .SYNOPSIS... Showers and thunderstorms chances continue through Wednesday, until a weak front passes. A mostly dry Thursday is expected, while another front provides another rain chance the following night and Friday. Near normal temperatures are expected. && .NEAR TERM /THROUGH WEDNESDAY/... As of 9pm, coverage of showers has actually increased over the last hour, particularly across eastern Ohio. This was the forecast of the HRRR several hours ago, although curiously the latest runs of the HRRR does not show as much precipitation anymore. Expanded coverage of likely pops, although backed off on coverage of thunderstorms as lightning observations have become quite isolated. Previous discussion follows. The upper low over the Deep South is in the process of filling and being absorbed into the mean eastern U.S. trough. Moisture continues to flow in from the south. Instability was sufficient to allow scattered showers to fire starting just before noon, but lightning has been quite scarce thus far, with overall CAPE profiles looking fairly skinny. A shortwave and surface boundary will approach from the west, lending support to continued showers and thunderstorms through the night. Models are focusing the more numerous showers/higher QPF across southwest PA and northern WV, and this is where the bulk of the likely PoPs reside. HRRR and NAM runs have suggested the potential for focused bands of higher QPF. While the actual numbers in these models are likely overdone, the pattern of isolated training heavy showers and storms is a reasonable one, and an isolated water issue or two is possible. Severe weather will likewise be very isolated at best, with colliding boundaries perhaps allowing for a stronger storm. The overall lack of instability and wind flow, plus insufficient dry air aloft, will prevent more widespread issues. Coverage will decrease late as instability starts to wane, albeit a bit later than typically seen. Low temperatures will end up a few degrees above climatology. && .SHORT TERM /WEDNESDAY NIGHT THROUGH THURSDAY NIGHT/... The shortwave and its associated cold front will cross on Wednesday. Showers and storms will flare up once again along and ahead of the boundary as it crosses, with likely PoPs along and east of a FKL/HLG line. Locally heavy downpours will remain possible with PWAT values still above 1.5 inches, although severe weather is not expected to be a threat. Rain chances will linger into Wednesday night as the front exits. Surface ridging will keep most of Thursday dry, although a shower or two could sneak into the northwest counties by sunset. Low pressure on the southern end of Hudson Bay will swing a cold front our way later Thursday night. Have kept PoPs in the chance range as moisture with this boundary will be somewhat more limited. Temperatures should average near or just above seasonal levels. && .LONG TERM /FRIDAY THROUGH TUESDAY/... The cold front will cross on Friday, with a continued chance of scattered showers and storms. We should be able to keep Friday night and Saturday mostly dry, although showers may eventually need to be added north of Pittsburgh as a weak wave rotates around the upper low, which will drift into Quebec. A general upper troughing pattern will then remain in place into early next week, with precipitation chances from Sunday on. Temperatures will generally run a few degrees below climatology through the period. && .AVIATION /02Z WEDNESDAY THROUGH SUNDAY/... Scattered convection overnight...primarily showers after midnight. Overall went a little more optimistic then guidance regarding cig/vis restrictions overnight...but may need to amend some sites to include IFR after midnight depending on how remaining convection plays out. Wind will veer from the ese to the wnw through the period with the passage of the front progged for tomorrow afternoon. OUTLOOK... Brief sub VFR weather is possible through Wednesday with an upper level low nearby. && .PBZ WATCHES/WARNINGS/ADVISORIES... MD...None. OH...None. PA...None. WV...None. && $$
Area Forecast Discussion
National Weather Service Pendleton OR
723 PM PDT Tue Jul 24 2018 .SHORT TERM...Water vapor imagery showing a weak short wave moving northward into the region this evening. Scattered thunderstorms have developed over southern Oregon. Currently the storms are just on the southern edge of our forecast area. The short wave is expected to continue to move northeast and may push the storms into our area for several hours this evening. At this point think the storms would be east of Bend across the John Day highlands. Mid and high level clouds streaming northeast across the Blues through the evening with mostly cloudy skies then clearing overnight. Further north across the Columbia basin and Yakima valley skies will remain clear through the night. The weather pattern remains similar Wednesday. Mainly clear skies in the morning then becoming partly cloudy across the south in the afternoon with some instability once again. Temperatures profiles support highs within 1-2 degrees of today readings. 94 && .PREV DISCUSSION... /issued 336 PM PDT Tue Jul 24 2018/ SHORT TERM...Tonight through Friday...Westerly flow will generally persist across south-central and southeast Washington through this period. Thus conditions will be fair and dry with above seasonal temps. A weak wave in the upper flow looks to sag into southwest British Columbia and western Washington late Thursday and Friday. There may be an increase in instability and mid level moisture due to this wave, which could result in stray showers/storms over western Kittitas county Friday afternoon. At this time, confidence in this outcome is low and will not mention with this package. The flow over eastern Oregon is more southwesterly, and this pattern is expected to hold into Wednesday morning. This flow will continue to allow mid and high level moisture to work into central, east- central and northeast Oregon. Expect to mainly see high based cumulus clouds and cirrus over these areas. Instability still looks to be strong enough to cause a few thunderstorms over the Ochoco- John Day Highlands late this afternoon and tonight. The flow over eastern Oregon is still expected to become more westerly Wednesday afternoon. Thus look for the deeper moisture and instability to be pushed south of our area by late Wednesday. Will therefore continue a fair and dry forecast across our Oregon zones Wednesday through Friday. Temps will continue to run above seasonal through this entire period across eastern Oregon. 90 LONG TERM...Friday night through Tuesday...An upper ridge will shift east as it builds over WA and OR Friday night through Monday. The ridge will keep conditions hot and dry. There will be some limited instability each afternoon but the moisture probably will be too limited for convection to develop. The GFS increases the moisture Monday and indicates a few storms may develop along the Cascades and over the northern Blue Mountains. However the ECMWF moves the ridge more slowly and keeps eastern OR and WA dry Monday and Tuesday. Due to lack of confidence I went with persistence and left the forecast dry. Both models show a marine push Tuesday. This will develop breezy winds in the typical Cascade gaps, including the Columbia River Gorge and Kittitas Valley, and allow temperatures to cool down. Coonfield AVIATION...00Z TAFs...VFR conditions with variable high clouds mainly in OR for the next 24 hours. Winds will be light and under 15 kts through the period. Winds will be strongest during the afternoon and evenings, especially along the gaps through the Cascades and the eastern Columbia River Gorge. 76 FIRE WEATHER...All zones will continue to observe hot conditions and low humidity--both daytime and nighttime--for the next five days. The westerly flow over WA and the northern half of OR is keeping any thunderstorms suppressed to the south. However, the southwest flow over the southern half of eastern OR has brought enough moisture for isolated to scattered thunderstorms the past couple of days. The biggest challenge has been where thunderstorms will develop and how many strikes will occur. Looking at the 12Z model runs, it was decided to issue a Red Flag Warning for Oregon fire zone 642 which covers Grant County south of John Day and northern Harney County. Even an isolated thunderstorm could bring a rate of 10-15 strikes per 15 mins, similar to what was observed in southeast OR last night. The HRRR is backing off on the thunderstorm potential in this zone, but visible satellite loops are showing cumulus building throughout southeast OR. The next focus for fire weather after today will be the shortwave trough tracking across northern WA Thursday and Friday. Any thunderstorms will be over the WA Cascades north of Snoqualmie Pass but will need to keep an eye if the trough digs farther south on Friday that it will need to be added to our WA Cascade zones. Wister && .PRELIMINARY POINT TEMPS/POPS... PDT 63 98 63 98 / 0 0 0 0 ALW 68 98 67 99 / 0 0 0 0 PSC 59 100 61 101 / 0 0 0 0 YKM 59 100 61 100 / 0 0 0 0 HRI 59 102 61 102 / 0 0 0 0 ELN 59 99 61 99 / 0 0 0 0 RDM 51 97 51 97 / 0 0 0 0 LGD 55 94 54 95 / 0 0 0 0 GCD 56 96 53 97 / 10 10 0 0 DLS 63 101 64 100 / 0 0 0 0 && .PDT WATCHES/WARNINGS/ADVISORIES... OR...Red Flag Warning until 11 PM PDT this evening for ORZ642. WA...None. && $$ 94
Area Forecast Discussion
National Weather Service Reno NV
844 PM PDT Tue Jul 24 2018 .UPDATE... Convection has decreased over all but the Western Nevada Basin and Range this evening. Thunderstorms over the basin and range country are producing gusty winds to near 45 mph and may be capable of producing blowing dust. Any blowing dust may briefly reduce the visibility along I-80 this evening east of Fernley. The storms should dissipate after 11 pm. Flooding is no longer a threat...although a few stronger storms may produce brief moderate to heavy to rain along with the gusty winds. With the flood threat waning...the Flash Flood Watch has been allowed to expire. && .PREVIOUS DISCUSSION... /Issued 211 PM PDT Tue Jul 24 2018/ SYNOPSIS... Thunderstorms remain possible Wednesday and Thursday afternoons but will be more isolated than previous days. A prolonged period of hot but not record breaking temperatures is expected into next week. Nearby fires will keep skies somewhat hazy into at least Thursday. DISCUSSION... Typical late July issues for the region. Here`s what we`re watching this afternoon: * Thunderstorms: Even with fairly favorable environment seen on 19z special sounding, storms have been slow to start. But we`re finally getting cells with a general northeast progression. SPC HREF guidance has storms winding down by 2100 PDT or so. Risk of severe and localized flash flooding remains so will continue flash flood watch with combined messaging on those hazards. Storms have more motion, so new fire starts perhaps an increased risk today. Have expanded storm chances Wed/Thurs northward closer to RNO as latest guidance has a little better environment for some isolated cells. Friday and through the weekend airmass trends decidedly drier and more stable to storm risk will be confined to the usual Eastern Sierra spots. * Heat: With large ridge holding over the region through at least mid next week, we`re looking at a prolonged period of hot temperatures and potential heat health impacts. Each day by itself likely won`t be record breaking but the accumulated heat could yield issues for sensitive populations. Guidance shows 7+ consecutive days of 100+ at RNO which is quite rare. Current record is 10 days in July 2005. One mitigating factor will be overnight lows not being excessively warm, especially this weekend with drier air and slightly longer nights at end of July. * Haze: Main fires we`re watching for smoke are near Yosemite and southern Oregon. Latest HRRR smoke model has haze over the region into at least Wednesday (and probably Thurs/Fri) with W/SW transport flow. Areas of thicker smoke will depend on fire activity, but if that happens Eastern Sierra south of Markleeville and NE California north of Susanville are at highest risk. -Chris AVIATION... Thunderstorms are the primary impact with scattered cells around the region through about 03z/Wed. Strong outflows to 40-50 kts, lightning, large amounts of small hail, and MVFR rains are potential impacts. Risk of seeing storms at TVL/TRK/SVE 5-10%, RNO/CXP 20%, MMH 40%, NFL/HTH/LOL 49%. Depending on rainfall today, patchy ground fog is possible late tonight in the usually prone valley spots such as TRK. Smoke and haze from Yosemite fire will bring reduced visibilities from MEV-MMH today and likely into Wednesday. Maybe into MVFR range at times. Some slight visibility reductions possible in NE California near SVE/AAT as well from fires in southern Oregon. Airmass projected to dry out slightly Wednesday but enough moisture may remain for a 10-30% chance of afternoon thunderstorms for RNO/CXP/MMH and points east. -Chris && .REV Watches/Warnings/Advisories... NV...None. CA...None. && $$ For more information from the National Weather Service visit...
Area Forecast Discussion
National Weather Service Blacksburg VA
920 PM EDT Tue Jul 24 2018 .SYNOPSIS... Upper level low pressure will continue to be the primary weather concern through Wednesday, bringing cloudy skies and scattered showers and thunderstorms. This low pressure system will begin to weaken and move out to provide much improved conditions for Thursday and Friday. && .NEAR TERM /THROUGH WEDNESDAY/... As of 915 PM EDT Tuesday... Bands of slow moving convection within the very moist low level southeast flow have shifted to a lingering moisture convergence axis just west of the area, and to along an earlier outflow out east where instability lingers near the residual front. Latest HRRR model suggests that some of this coverage will linger espcly east until around midnight and in spots across the mountains where added bands could pop up and not move much per so much moisture around. Thus keeping at least likely pops going across the east/west a bit longer with much less coverage in between where in between lift sources. Once the showers finally fade out after midnight, expect to see another round of low clouds/fog into the early morning hours pending degree of debris clouds around. Little change to going temps with lows mostly 60s to around 70 overall. Previous discussion as of 300 PM EDT Tuesday... Pattern persists regarding deep upper trough that has been in place over the Eastern CONUS for the past several days. Thus far, the forecast area has missed the bulk of the heaviest rainfall associated with this feature. Since the situation for Tuesday is nearly identical to the past few days, there is not much justification to stray too far from a persistence forecast. Therefore, limited coverage of showers and thunderstorms right now will increase going forward, will begin to drop around sunset, and should be fairly isolated by midnight. Low stratus and fog will again be possible during the overnight hours. The pattern will begin to change some on wednesday as the trough weakens, however plenty of moisture will still exist to maintain some isolated coverage of showers through the morning with again, another increase in coverage during the afternoon hours, however, at this point, expecting said coverage to be much less than previous afternoons. Severe threat is minimal due to insufficient surface heating and is mirrored by SPC outlooking only for general thunder both days. Flooding remains the main threat for the forecast area for today with WPC having a slight chance for excessive rainfall for the second consecutive day, covering most of the forecast area. While some areas are likely to see a decent amount of rain, forecast models are not as impressive as yesterday regarding large amounts in any particular location which is what prompted the watch. Therefore, while any very heavy downpours occurring in a very short period of time could still become problematic and will be monitored for, watch issuance at this time does not appear . && .SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY NIGHT/... As of 300 PM EDT Tuesday... Mid/upper-level pattern undergoes transition Wednesday night through Thursday, as the upper-level low responsible for days of showers and thunderstorms over the eastern U.S. is expected to deamplify and lift into the Northeastern CONUS. The mid-Atlantic and Appalachians and the northern Carolinas then project to be in a broad cyclonic flow aloft, on the southern periphery of a upper-level low to be centered over northern Lake Superior. Weak surface high pressure builds in Thursday affording a brief reprieve from cloudy and wet conditions, before a weak shortwave trough and associated surface cool front then progress across the region for Friday. May still be some leftover showers early Wednesday night mainly from the WV/VA border eastward as the upper low exits, but should trend dry by midnight. With high pressure building in, weak to calm surface winds for the overnight combined with rather damp ground could prove to be a favorable environment for patchy fog even away from river valleys. Not currently thinking dense fog but will include patchy fog for Wednesday night for most locales. As mentioned, looks like Thursday into Thursday night should be generally uneventful for many. If there is one area that may see a renewed chance for showers or thunderstorms, it`s along a lee trough/wind shift line progged by the GFS from about Fredericksburg VA southwest into the Reidsville NC area eastward. Prospects for rain overall are pretty low though and will keep PoPs no higher than lower end of Chance (25-30%) during the afternoon. Thursday night looks dry however. Friday looks the more active of the period, with a cold front approaching from the west. That being said, there`s still some level of uncertainty inherent in recent and today`s 12z guidance on timing the front eastward. In fact today`s guidance has slowed the front down about 6 hrs, opting for a mid-afternoon through overnight eastward progression. There`s enough, albeit waning instability progged between the lower GFS and the higher NAM to support at least garden variety thunderstorms. Deep-layer wind shear profiles is mostly unidirectional speed shear with values between 20-30 kts, though the strongest wind shear lags the frontal zone where the better 700-500 mb winds should lie. There`s also a considerable amount of dry air in mid-levels that`s forecast in BUFKIT soundings, with dry entrainment as another potential limitation. Not quite an ideal setup for strong/severe thunderstorms given the unfavorable timing of the frontal lift offset from peak heating and the dry entrainment, but still enough uncertainty to at least keep that possibility open. As the front moves into Southside and the upper NC Piedmont, it`s low-level thermal gradient begins to slow and stall as it moves into eastern VA, suggesting that at least some chances for lingering overnight showers in southeastern sections is warranted. Temperatures overall are within a few degrees of normal for late July. && .LONG TERM /SATURDAY THROUGH TUESDAY/... As of 300 PM EDT Tuesday... Overall a rather unsettled period for the extended, spanning from this coming weekend into early next week. Stalled front from late Friday night will drift eastward into Saturday, still serving as a focus for some showers or thunderstorms mainly south of the Roanoke River into the NC counties. On Sunday, that stalled front then begins to return back northward in response to a shortwave trough pinwheeling around the broad longwave trough aloft. Should have increasing PoPs toward solid Chance/low Likely for Sunday. Monday into Tuesday, digging trough energy into the Mississippi Valley projects to bring a south-southwesterly tap of Gulf moisture northeastward across the eastern third of the country. PoPs were kept at high Chance/low-Likely range for early next week as we may be looking at daily rain chances again. Temperatures stay about near normal for the weekend, but then tend near to below normal for early next week - below normal particularly on the highs with abundant cloud cover. && .AVIATION /01Z WEDNESDAY THROUGH SUNDAY/... As of 700 PM EDT Tuesday... The deep trough over the region will continue to be the weather maker for the forecast period. As has been the case the past several days, variable ceilings and showers and thunderstorms will continue to be of concern to aviation interests. Expect most locations will be at VFR into this evening before showers fade and low clouds/fog fill back in. This will again result in areas of MVFR/IFR cigs/vsbys in most locations later tonight with local sub-VFR in any of the showers this evening. Then expect a return to VFR conditions by Wednesday afternoon before the storms begin firing up across parts of the region. Appears best chances of shra/tsra on Wednesday will again be over eastern sections but enough to include a vicinity mention elsewhere as the current axis of moisture over the mountains pushes east during the afternoon. Extended Aviation: Beyond the forecast period on Wednesday, expect much of the same during the afternoon and evening hours, however by this time the upper low will have begun to fill and will start to become absorbed in the prevailing flow. Coverage of showers and storms will become noticeably reduced and a marked improvement to the conditions should be apparent by Thursday. VFR conditions should be fairly prevalent, however, still can not rule out some typical summertime, isolated showers and thunder during the afternoon hours espcly later Friday and again on Sunday. Also, saturated soil conditions could still lead to some low stratus/fog the next couple of nights. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...None. NC...None. WV...None. && $$ SYNOPSIS...JR NEAR TERM...JH/JR SHORT TERM...AL LONG TERM...AL AVIATION...JH/JR
Area Forecast Discussion
National Weather Service Tucson AZ
855 PM MST Tue Jul 24 2018 .SYNOPSIS...Expect very hot daytime temperatures through tomorrow with record highs likely once again. Isolated to scattered thunderstorms through midweek will mainly occur near the mountains. More extensive thunderstorm coverage is then expected late this week and especially this weekend as temperatures moderate closer to seasonal normals. && .DISCUSSION...Record high temperatures were handed out to several locations this afternoon, including KTUS with 112 and KDUG climbing to 104. A few remaining showers and thunderstorms were ongoing as of 330Z this evening, mainly east and south of the Tucson area. An outflow boundary was also well-defined via IR satellite imagery across Graham and Cochise Counties due to earlier thunderstorms across the higher terrain. It is possible this boundary could invigorate a few more showers or storms to pop up over the next few hours as it progresses southwestward. The latest HRRR attempts to depict this solution, but with it`s poor handling of today`s earlier convection, confidence is not high on this scenario. Convection on Wednesday should be just a tad more than today with the best action again east and south of Tucson and near terrain, especially during the peak heating of the day. With high pressure quasi-stationary for the next 12-18 hours, high temperatures will again near record levels during the afternoon and the Excessive Heat Warning will remain in effect through Wednesday evening. No updates at this time. Please see the remaining sections for additional details. && .AVIATION...Valid through 26/06Z. SCT-BKN clouds with bases 10-15k ft AGL and isolated to scattered -TSRA/-SHRA possible mainly E of KTUS into late this evening. Isolated to scattered -TSRA/-SHRA will occur again Wednesday afternoon, mainly near terrain. SFC wind variable in direction mainly less than 12 kts through the period except for in/around thunderstorms where gusts of 35-40 kts may occur. Aviation discussion not updated for TAF amendments. Be advised that very hot daytime temperatures are forecast to occur through Wednesday. This extreme heat will cause density altitudes to approach impact thresholds for some aircraft. && .FIRE WEATHER...Isolated to scattered thunderstorms through Wednesday will mainly be confined to locations east and south of Tucson. A better flow pattern will allow for an increase of thunderstorm chances for the latter half of the week into the weekend. Aside from gusty thunderstorm outflows, 20-foot winds will be terrain driven and generally under 15 mph. An exception is Wednesday afternoon when occasional gusts to 25 mph should occur across the Upper Gila River Valley. && .PREV DISCUSSION...An extremely strong and deep area of high pressure continues to dominate our weather, with an H5 value of 600dam directly overhead this afternoon. The NAEFS Ensemble shows maximum percentile climatological values for both 500mb and 700mb into Thursday. As such, our main short-term story will continue to be the excessive heat at least through Wednesday. Some debris with embedded showers west of Tucson earlier today has slowed heating down a few degrees, but not so from Tucson eastward. We broke a record at TUS with 110 and still have a little more time to cook. Meanwhile, moisture is a little below average in eastern areas, but with the best solar insolation, eastern mountains are finally getting started with a thunderstorm or two. Limited convective potential in valleys so storms will likely hang closer to higher terrain. The rest of the afternoon and evening should favor areas south of Tucson. The high should fill a bit and start to slowly shift northwestward as the larger scale flow loses a little amplitude upstream and downstream over the next 72 hours. As this happens, temperatures will fall back closer to climatology, and the enhanced easterly flow should bring in more moisture and sharpen our thunderstorm chances by Friday. GEFS plumes show a mean around 1.5 inches precipitable water returning by late Friday along with a general increase in surface based CAPE. We will be back to a near normal late July forecast for both temperatures and thunderstorm chances by Saturday. && .TWC WATCHES/WARNINGS/ADVISORIES... Excessive Heat Warning until 8 PM MST Wednesday for AZZ501>509. && $$ Carpenter/Meyer/Pegram Visit us on Facebook...Twitter...YouTube...and at
Area Forecast Discussion
National Weather Service Las Vegas NV
725 PM PDT Tue Jul 24 2018 .SYNOPSIS...A disturbance moving from southern Nevada toward southwest Utah will enhance thunderstorm development through this evening. Storms should be more inhibited across much of the region Wednesday and Thursday, except the southern Sierra and high mountains as a strong area of high pressure builds over the southwest states. This will lead to dangerously hot conditions across the Mojave Desert and southern Great Basin much of this week. && .UPDATE...Thunderstorm activity appears to be gradually decreasing this evening as sunset approaches and dynamic support moves out of the forecast area. Still seeing some isolated to scattered activity across Lincoln and Northern Mohave counties, and will continue to monitor trends for any possible westward backbuilding, but at this time thunderstorm development into far southern Nevada seems unlikely. Will continue to monitor trends this evening and adjust the forecast grids accordingly, but overall the forecast is in good shape. -Outler- .AVIATION...For McCarran...A push of northeast winds this evening is beginning to appear less likely, with generally light winds favoring diurnal trends expected through Wednesday. Temperatures will be quite hot again, with temperatures exceeding 110 degrees during the afternoon. For the rest of southern Nevada, northwest Arizona and southeast California...Thunderstorm activity is on the decrease but a stray thunderstorm cannot be ruled out completely through 4z. Beyond thunderstorm influences, generally tranquil weather is expected with winds less than 15 knots and SCT clouds with bases above 12 kft. && .SHORT TERM...through Thursday night. Thunderstorm development has been aided today by a disturbance which could be seen on water vapor imagery lifting from southeast California up over southern Nevada. Most operational models indicate this will continue moving over southeast Nevada and southwest Utah. Convective cell movement will be to the north-northeast around 15 mph though this evening. One thing worth noting, recent runs of the HRRR model indicate the possibility of storms around southeast Nevada and southwest Utah producing southwestward propagating cold pool which could bring storms down the I-15 corridor toward Las Vegas later this evening... as we have already seen more than a few times this month. It`s worth watching. The threat of outflow induced thunderstorms will diminish late this evening and overnight. The biggest impact through Thursday continues to be the excessive heat which has been long advertised. The moisture that has provided fuel for thunderstorms will largely be trapped under the strong area of high pressure which will be migrating from eastern Arizona directly over southern Nevada and surrounding states...and likely becoming anchored the rest of the week. This will help stabilize the atmosphere...along with boosting temperatures...but will not completely eliminate the chance of thunderstorms over the mountains and especially the higher terrain near central Nevada. .LONG TERM...Friday through Monday. Models forecast a high pressure ridge holding tough over the western CONUS Friday through Monday. Confidence in the temperature forecast is wavering a bit with MOS guidance now extending hot conditions (110+ in Las Vegas) into Saturday. Although temperatures are forecast to decrease a degree or three on Friday, some consideration may be needed in extending the Excessive Heat Warning through Friday and, if MOS guidance trends continue, possibly Saturday as well. The reasoning would not be due to near record heat as covered under the current warning but, factoring in the duration of the event and the increasing outdoor activity heading into a weekend. Models show a general increasing trend in moisture with PWAT values from .75-1.00 inch across the CWA Friday to more than an inch PWATs over the southern half of the forecast area by Monday. The areas of forecasted deeper moisture coupled with daytime instability and the potential for weak uplift provided by disturbances or boundaries could fuel a few thunderstorms over the far southeastern CWA. This would be especially true if the high center were to shift a little bit to the east, presenting a more favorable steering flow. && && .CLIMATE...Near record temperatures are expected through Friday this week. The table below shows the record temperatures this week and the year recorded for McCarran (Las Vegas), Death Valley, Needles, Barstow/Daggett, Bishop and Kingman. RECORD HIGH TEMPERATURES (YEAR) --------------------------------------------- TUE (7/24) WED(7/25) THU(7/26) FRI(7/27) LOCATION --------------------------------------------- McCarran | 117 (1942) 115(1942) 116(1943) 115(2016) Death Valley | 126 (2006) 126(2006) 127(1933) 127(1933) Needles | 119 (2006) 120(1943) 118(1959) 119(2016) Barstow/Daggett | 112 (2016) 115(1975) 114(1995) 115(1995) Bishop | 107 (2016) 107(2016) 108(1975) 108(2016) Kingman | 107 (1928) 107(1943) 108(1934) 108(1934) && .SPOTTER INFORMATION STATEMENT...Spotters are encouraged to report any significant weather or impacts according to standard operating procedures. && $$ SHORT TERM...Adair LONG TERM...Salmen AVIATION...Wolf CLIMATE...Boothe For more forecast information...see us on our webpage: or follow us on Facebook and Twitter