####018005893#### FXUS65 KPSR 032235 AFDPSR Area Forecast Discussion National Weather Service Phoenix AZ 335 PM MST Fri May 3 2024 .SYNOPSIS... Slightly above normal temperatures are expected through tomorrow, with afternoon highs peaking in the low to mid 90s across the lower deserts. A dry weather system will traverse the Intermountain West this weekend leading to widespread breezy to windy conditions Saturday evening and Sunday, as well as cooler temperatures on Sunday and Monday. Dry weather will persist through next week, and temperatures are expected to rebound into the low 90s by early next week. && .DISCUSSION... Dry, warm weather continues across the region today as quasi-zonal flow persists across the southwestern CONUS. Afternoon visible satellite imagery showed mostly clear skies persisting across the CWA as dry southwesterly flow aloft continues. Through tomorrow, 500 mb heights will remain consistent around 572-575 dm for our area and thus high temperatures tomorrow will be similar to today's in the low to mid 90s across the lower deserts. Light winds today will give way to increasingly stronger winds starting tomorrow in response to an approaching weather system that will impact the region this weekend. The aforementioned weather system is currently seen on satellite WV imagery off the Pacific Northwest coast. Guidance show this closed low diving southward along the West Coast through the start of the weekend before progressing inland across the Great Basin Sunday. Though the greatest negative height anomalies will remain north of our area, decreasing heights and increasing gradients will promote strong winds and cooler temperatures as we head through the weekend. Strong winds will pick up across southeast California starting tomorrow afternoon/evening, particularly across Imperial County and Joshua Tree National Park where gusts are likely (>80%) to exceed 40 mph at times. Wind Advisories are in effect for these areas and the Wind Advisory for much of Imperial County is now in effect through Sunday evening. Sunday, strong winds will spread across Arizona as the closed low moves inland across the Great Basin while the associated dry cold front moves through the region. Wind gusts are likely (>70%) to climb upwards of 30-40 mph across much of the forecast area, while some areas may see gusts in excess of 40 mph at times, particularly areas across Imperial County and southern Gila County. Additional Wind Advisories may be needed for some areas as we get closer. The strong winds this weekend may lead to the development of dust channels across dust prone areas, which could reduce visibilities and make travel hazardous. Outside of the strong winds, temperatures will fall below normal Sunday, especially across southeast California and southwest Arizona where well below normal highs are only forecast to top out in the upper 70s to low 80s with the passage of the cold front. Across south-central Arizona, temperatures won't see as significant of a drop with lower desert highs Sunday in the mid to upper 80s. The closed low will eject to the northeast for the start of the new workweek with lighter winds prevailing across the region. Global ensembles then favor longwave troughing persisting across the western CONUS through much of next week. Temperatures will gradually warm back up near to slightly above normal with daily afternoon highs across lower elevation areas climbing into the low to mid 90s. && .AVIATION...Updated at 1730Z. South-Central Arizona including KPHX, KIWA, KSDL, and KDVT: No aviation weather concerns under clear skies are expected through the TAF period. Wind pattern will continue to exhibit diurnal tendencies with a period of southerly winds through early this afternoon before fully transitioning out of the west. Speeds will generally remain under 10 kts, although a few occasional gusts in the mid-teens cannot be ruled during the afternoon and early evening hours. Southeast California/Southwest Arizona including KIPL and KBLH: No aviation weather concerns under clear skies are expected through the TAF period. Winds will generally be southerly through the period at BLH aob 10 kts, while southeasterly winds at IPL are expected to become westerly during the evening hours. && .FIRE WEATHER... Warm and dry weather will persist into this weekend, with light and diurnal winds and typical afternoon breeziness today. Afternoon highs will remain slightly above normal through tomorrow in the low to mid 90s across the lower deserts. Gusty winds will begin to increase across the region in response to an approaching weather system starting Saturday afternoon/evening, particularly across parts of southeast California where gusts are expected to exceed 40 mph at times. Strong winds increase across Arizona heading into Sunday afternoon with gusts across south-central and southwest Arizona climbing upwards of 30-40 mph and some gusts potentially exceeding 40 mph, particularly across southern Gila County. The strong winds and dry conditions will lead to elevated to locally critical fire weather conditions this weekend. Min RHs through the weekend will be around 10-20%, while overnight Max RHs will be around 30-60% for most areas. && .PSR WATCHES/WARNINGS/ADVISORIES... AZ...None. CA...Wind Advisory from 3 PM Saturday to 9 AM PDT Sunday for CAZ560. Wind Advisory from 3 PM Saturday to 8 PM PDT Sunday for CAZ563>567. Wind Advisory from 3 PM Saturday to 11 PM PDT Sunday for CAZ562. && $$ DISCUSSION...Smith AVIATION...Lojero/Kuhlman FIRE WEATHER...Smith ####018008096#### FXUS64 KMAF 032236 AFDMAF Area Forecast Discussion National Weather Service Midland/Odessa TX 536 PM CDT Fri May 3 2024 ...New AVIATION... .SHORT TERM... (This afternoon through Saturday night) Issued at 101 PM CDT Fri May 3 2024 WV imagery shows the upper trough persistently parked over SoCal/Baja, leaving West Texas and Southeast New Mexico under southwest flow aloft. At the surface, a dryline extends from KTAT- KINK-KFST-K6R6. Td at KMAF @ 1430Z was 67F. As such, the 12Z KMAF RAOB came in w/4000 J/kg mucape, LI ~ -12, w/mesoanalysis suggesting what little cap there is is either already gone or soon will be. mid- lvl lapse rates are ~ 8.5 C/km, and environmental deep-layer shear 30kts. Shear is forecast to increase through this afternoon, and really ramp up tonight as the west coast trough begins moving east and a 40+kt LLJ ramps up after sundown. Needless to say, a continuing supercell threat is on tap for this afternoon/tonight along the dryline and last night's boundary that moved in from the northeast. We'll be throwing another balloon up at 18Z to further monitor the situation. S strong LLJ overnight and cloud cover will keep lows 5-7F above normal. Saturday, the west coast trough is forecast to be over southeast Arizona at 12Z-18Z, and arrive in West Texas 21-00Z. At the surface, a boundary from tonight's convection is expected to shove the dryline to the western border of the CWA, while a front pushes into the northeast by late morning, putting practically the whole of West Texas and Southeast New Mexico in the warm sector. Deep-layer shear increases to 30-40 kts, stretching out the hodographs, and lapse rates approach 10 C/km in the west near the dryline. Convection looks to get going earlier and farther west than any event yet this spring, and more widespread as well. The only promising detail is that forecast soundings saturate quite a bit by 00Z Sunday, w/PWATS at KMAF ramping up to over 1.5", which is about 2.5 std devs above the normal of 0.60". So perhaps some areas west of the Pecos, that really need it, may see a little relief. The other edge of that sword will be lightning-induced fire starts. The front will bring in cooler temperatures, and expected cloud cover/convection should keep highs right around normal. This activity could continue well into Saturday night. As the front settles in and instability decreases, there's indications this may transition to a heavy rain scenario, w/maybe even a little training along the front as it moves south. Lows will remain above normal. && .LONG TERM... (Sunday through Thursday) Issued at 101 PM CDT Fri May 3 2024 Things begin to quiet down after an active day on Saturday for your Sunday. Any thunderstorms that may be lingering across the eastern and southeastern portions of the region should continue to weaken and slide off to the southeast through the morning hours. The combination of cloud cover and a convectively worked over airmass may limit further thunderstorm activity through the late morning and afternoon on top of resulting in slightly cooler temperatures. Filtered sunshine should still allow for upper 70s and even 80s across the bulk of the area but any 90s are confined to the Rio Grande Valley. Though large scale support is expected to be waning as we transition to the backside of a departing trough, daytime heating may still result in enough destabilization along and east of the dryline for scattered thunderstorms during the afternoon. The best chance of any additional thunderstorms will be focused across the eastern third of the region. Overnight temperatures remain mild in the 50s and 60s as the dryline sloshes back west, ushering in greater dewpoints. A relatively benign pattern takes over by the start of the new week. A large negatively-tilted trough is forecast to be lifting into the central and northern Great Plains on Monday. This acts to mix the dryline all the way east of the region, meaning we are warm and dry. This allows temperatures to quickly climb back into the 90s for the majority of locations. At night it remains warm but not as muggy with the dryline staying east. It should be slightly cooler further west behind the dryline. Tuesday and Wednesday see a similar forecast as Monday, albeit with slowly warming temperatures each day as quasi-zonal flow is maintained over the southern Great Plains. The next potential change in the forecast may not arrive until late in the week. A large positively-tilted trough axis appears to take shape from the Great Lakes to central Rocky Mountains. This may be enough to push a cold front south through portions of the area beginning sometime Thursday bringing cooler weather for some, especially on Friday. At this time, the dryline remains to the east and little moisture is expected behind the cold front. This means all of next week may be dry... Enjoy any rain while it lasts! -Chehak && .AVIATION... (00Z TAFS) Issued at 533 PM CDT Fri May 3 2024 Convection will be possible this evening, as well as near the end of the forecast period, but chances are too low or too far out for a mention attm. Return flow will remain slightly elevated overnight due to a LLJ developing, w/MVFR stratus expected late tonight/early Saturday all terminals. This will persist through the morning hours, except KMAF, where NBM suggests it'll hang in all day. && .FIRE WEATHER... Issued at 101 PM CDT Fri May 3 2024 A Fire Danger Statement remains in effect through this evening for southeast New Mexico and the Guadalupe Mountains. A passing disturbance this afternoon is causing relatively breezy conditions over the critically dry airmass behind the dryline in an area of ERCs exceeding the 90th percentile. Saturday should be very similar to today, though moisture and rainfall potential is expected to be pushed further west, limiting any fire weather concerns to the westernmost areas where elevated conditions are maintained behind the dryline. Sunday it continues to be dry behind the dryline from the western foothills to the Big Bend where locally elevated to near- critical fire weather may continue to be possible. Fire weather concerns ramp up into next week. A stronger trough passes to our north on Monday. This not only pushes the dryline east of the entire area meaning critical relative humidity for almost everyone, but winds are going to increase, especially across southeast Mexico and the higher terrain. Given the lack of rain and critically dry fuels out west, widespread critical fire weather is anticipated. Further to the east, while it remains dry, recent rainfall and better moisture return should limit fire potential. This trend continues Tuesday and Wednesday, though winds will slacken some, perhaps resulting in more localized critical conditions. A cold front is set to arrive by late week and may temporarily limit fire weather across much of the region. -Chehak && .PRELIMINARY POINT TEMPS/POPS... Big Spring 60 81 59 77 / 40 70 80 30 Carlsbad 58 87 59 88 / 0 20 40 0 Dryden 66 87 65 84 / 20 30 60 30 Fort Stockton 63 90 62 85 / 20 40 60 20 Guadalupe Pass 57 81 57 82 / 0 10 20 0 Hobbs 57 82 56 81 / 10 50 60 10 Marfa 50 88 51 87 / 10 10 20 10 Midland Intl Airport 61 82 60 79 / 20 60 80 20 Odessa 62 83 61 79 / 20 60 70 20 Wink 61 90 62 87 / 10 40 60 10 && .MAF WATCHES/WARNINGS/ADVISORIES... TX...None. NM...None. && $$ SHORT TERM...44 LONG TERM....91 AVIATION...44 ####018009281#### FXUS65 KREV 032238 AAA AFDREV Area Forecast Discussion...UPDATED National Weather Service Reno NV 338 PM PDT Fri May 3 2024 .SYNOPSIS... Warmer temperatures continue today, with light winds. Active weather returns tomorrow with a storm system bringing gusty to strong winds along with valley rain and mountain snow, with conditions slowly improving Sunday. For next week, a slow warming trend with low chances for precipitation remains in the forecast. && .DISCUSSION... REST OF TODAY: The latest RAP analysis shows the CWA underneath a weak upper air ridge this afternoon with a pretty robust upper air low residing over the Pacific Ocean west of the U.S./Canada border. Current surface observations report back mostly light and variable winds with a few breezy gusts out of the east in some locations. Model guidance then forecasts the low to move southeast towards the U.S. coast going into the night and pushing the ridge to the east. At the surface, daytime high temperatures expect to range between the 60s to the lower 70s with cooler highs in the Sierra Crest. While most of the region expects to stay dry, the HREF shows a 10-20% probability for an isolated shower or two later this afternoon/evening in Mono County and the bordering areas though not much moisture is expected with these showers. THE WEEKEND STORM: Forecast guidance projects the upper air low continuing a progression towards the CWA throughout Saturday and then passing over the northern portion of the CWA on Saturday Night and going into Sunday morning. By late Sunday evening, the low is forecast to have moved east of the CWA allowing for a north- northwesterly flow over the CWA going through the night. With this upper air pattern, a low pressure system looks to move east- southeastward across OR on Saturday and make its way over northern UT by Sunday morning. This will cause a quick moving cold front to begin to sweep across the CWA on early Saturday morning. This front will cause the region to see two impactful weather concerns for Saturday: gusty to strong southwesterly winds along with winter-like precipitation including accumulating mountain snow and valley rain. * Winds: Upon looking at the latest ECMWF EFI (Extreme Forecast Index) for wind gusts on Saturday, there is a "bulls-eye" of 0.90- 0.99 values in southern portions of the region (southern Lyon, Mineral, and Mono counties) that slowly lowers going northward into the CWA. There is a second maximum seen in northern Washoe county as well of 0.8-0.9. What this means is that there is a really good signal for strong (~60+ mph) wind gusts within the region on Saturday. Please refer to the High Wind Warning as well as the Wind Advisories for more detailed information on expected maximum wind gust values as well as locations. There is also information on strong winds contained within the Winter Weather Advisory and Winter Storm Warning that should be referenced as well. These winds will cause hazardous traveling conditions including potential blowing dust beginning on Saturday morning and going into the evening. Travelers are encouraged to check conditions within the region be embarking on their journeys. The winds look to decrease a bit by late Saturday night/early Sunday morning as the system moves more eastward away from the CWA. * Snow and Rain: With the latest QPF updates, snow totals particularly for the Sierra Crest and Tahoe Basin have come up a bit on Saturday and going into Sunday. As a result, the Winter Weather Advisory on Saturday and Sunday for the Lake Tahoe Area and Mono County has been upgraded to the first ever NWS Reno Winter Storm Warning issued for the month of May in recent history. Lassen, Eastern Sierra and Eastern Plumas counties remain in the Winter Weather Advisory Please refer to the Winter Weather Advisory and the Winter Storm Warning for more details such as timing, locations, and forecast snowfall amounts for the these areas above 5000 feet. Weather.gov/rev/winter also is a source for this information along with the latest Winter Storm Severity Index (WSSI) which shows moderate to major impacts along the Sierra Crest and some of the mountain passes. The latest HREF is showing the potential for 1-2 inch per hour snowfall rates in the afternoon and evening which is not very common to see this time of year. Once again, travelers should be prepared due to the expected hazardous traveling conditions in these areas that will include blowing snow (with the strong winds) and accumulating snow that may cause slick roadways. While the higher elevations see good snowfall chances, lower elevations particularly in the valleys will see rain more as their P-type though some areas may see some snow mixed in on Saturday night with temperatures cooling and snow levels dropping. Snow flurries may be possible going into Sunday morning within western NV. The latest QPF values range from around a trace in Mineral county to around almost 2 inches in the Sierra Crest on Saturday and Sunday. Precipitation chances look to begin Saturday morning in the west with the front approaching and spread through the rest of the CWA by the afternoon hours. These chances then look to depart out the east with the system by late Sunday afternoon allowing for a drier evening and night. * Temperatures: Temperatures do come crashing down and are pretty cold for May standards on Saturday and especially Sunday due to the cold front passage. High temperatures will be upwards of 15-20 degrees below average, as the region barely reaches 40 degrees for Sierra communities with western NV seeing lows as high as the low to middle 50s. There is additionally the chance for sub-freezing temperatures in western NV and northeast CA on Sunday morning as well as Sunday night into Monday morning. BEYOND THE WEEKEND: Model guidance shows the upper air low opening up into more of a negatively tilted trough on Monday over the Rocky Mountains allowing for a mostly northwesterly flow over the CWA that continues through Tuesday. It also continues into Wednesday with the trough becoming more neutral over the central CONUS as a ridge moves over the Pacific Coast. As a result, temperatures look to rebound a bit though still being cooler on Monday before slightly cooling on Tuesday with a warming trend beginning on Wednesday. While the upper air pattern is unsettled at this time, signals do point to the warming trend continuing through Thursday and Friday. Precipitation chances look to be minimal at best currently during the next work week. There may be some fog concerns during the morning hours around the Truckee area during mornings to begin the work week, so will continue to monitor this potential. -078 && .AVIATION... * Friday will feature pleasant flying conditions with light winds and mostly clear skies into the evening. There are a few showers around KMMH into the eastern Sierra that will quickly dissipate after sundown this evening. Weekend Storm Update: A strong, unseasonably colder spring storm system is moving into the region overnight tonight through Saturday. * Snow/Rain: Widespread mountain snow showers and valley rains are likely (>70-90%) overnight into Saturday evening throughout the northeast CA, the Sierra, and western NV. This colder airmass will allow for snow levels to drop to 5000-5500 feet by Saturday night. Sierra terminals KTRK, KTVL, and KMMH could see between 3-5" of snowfall with a 80-90% chance for at least 2". However, high sun angle in May may limit accumulations on runways at those terminal during the day. There is also a slight chance for snow flurries Saturday night into Sunday morning for far western NV terminals (KRTS-KRNO-KCXP-KMEV). * Winds: Strong west to southwest winds will increase across the Sierra overnight and continue through Saturday night. Look for sustained ridgetop winds across the Sierra of 40-50kts with gusts upwards of 70-90kts during this time period. Expect periods of mountain wave turbulence, as well as LLWS for all area terminals. Strong west to southwest winds are possible as well for all western NV and Sierra terminals through Saturday. -Amanda && .REV Watches/Warnings/Advisories... NV...Wind Advisory from 8 AM to 5 PM PDT Saturday NVZ005. Winter Storm Warning from 11 AM Saturday to 8 AM PDT Sunday NVZ002. High Wind Warning from 8 AM to 8 PM PDT Saturday NVZ001-003. Lake Wind Advisory from 8 AM to 8 PM PDT Saturday NVZ004. CA...Wind Advisory from 8 AM to 5 PM PDT Saturday CAZ070. Winter Weather Advisory from 11 AM Saturday to 8 AM PDT Sunday CAZ071. Winter Storm Warning from 11 AM Saturday to 8 AM PDT Sunday CAZ072-073. && $$