####018005230#### FXUS64 KMRX 180001 AAA AFDMRX Area Forecast Discussion...UPDATED National Weather Service Morristown TN 801 PM EDT Wed Apr 17 2024 ...New AVIATION... .SHORT TERM... (This evening through Thursday) Issued at 300 PM EDT Wed Apr 17 2024 Key Messages: 1. Rain to come to an end late this afternoon into early evening. 2. Dry and warm daytime Thursday. Discussion: The band of rain showers that has primarily afflicted those south of Knoxville will continue to thin out as it progresses eastward for the remainder of the day. Only a few rumbles of thunder occurred in the southern valley today, and outside of a rare rumble of thunder, nothing much is expected for the remainder of the day outside of the rain. A medium amount of clearing will occur overnight, with patchy fog and low clouds possible in the morning. The upper trough over the Midwest will move off to southern Canada, and the jet stream helping power today's rain will move south of us tonight. The movement of these features allows for a mid level ridge to build in over us for Thursday. Clearing skies and building heights will allow for temperatures to rebound tomorrow, with valley temperatures in the low 80s for most of the region. Records for April 18th: CHA 90/2002 TYS 90/1896 TRI 87/2002 Compared with the records for the day guidance has persisted in remaining a few degrees below the daily records. The SREF & NBM probabilities indicate some low thick clouds in the morning hours, but those are expected to mix out and clear heading into peak heating. Otherwise relative humidities will drop below 40% in northern Tennessee into southwest Virginia tomorrow afternoon. && .LONG TERM... (Thursday night through next Wednesday) Issued at 300 PM EDT Wed Apr 17 2024 Key Messages: 1. Showers and thunderstorms return for Thursday night and Friday. There is a low chance of strong to severe storms with gusty winds and hail. 2. Turning much cooler this weekend, with some showers around especially Sunday. 3. Mostly dry with a warming trend Monday through Wednesday. Discussion: We start the period with a low pressure system moving out of the Mississippi Valley and tracking northeast into the Great Lakes region. This system will drag a cold front through our area Friday. We will see showers and thunderstorms moving in Thursday night out ahead of the front and continuing Friday as the front moves through. Models generally indicate there will be modest instability, perhaps as high as 500-1000 J/kg in the south early Thursday night, and there is some shear although effective shear looks quite low to start and then is forecast to increase to around 30+ knots later in the night although after the period with better convective energy. Right now the strong to severe threat still looks limited, but a few storms with strong gusty winds and hail are possible especially Thursday night with the highest threat across our southern areas and along/near the Plateau. There is significant model disagreement for Saturday, with the NAM bringing additional showers to the area as the colder air pushes in behind the front, but much of the other model data does not support this idea so will go with the NBM solution and just carry slight chance PoPs for the eastern mountains and far south Saturday closer to the boundary. It will be cooler with high temperatures expected to be near or a bit below seasonal normals. A weak system to our south may brush the area with additional showers Sunday especially across the south and east, and it will be quite cool with high temperatures expected to be well below seasonal normals. Monday through Wednesday look mostly dry with a gradual warming trend, although a weak frontal boundary may drift into the area by Wednesday with a few showers and/or thunderstorms. && .AVIATION... (00Z TAFS) Issued at 756 PM EDT Wed Apr 17 2024 Guidance suggests widespread fog and low clouds will be an issue across the region tonight. Though CIGS are bouncing in and out of MVFR territory at KCHA at the moment, their presence gives confidence to the lower flight categories forecast tonight. Most confident in this occurring at KCHA where almost an inch of rain fell, so LIFR categories seem ok there. Will limit categories to MVFR at KTYS and KTRI where confidence is lower. Expect to see a return to VFR levels between 14-16z tomorrow morning. Winds will remain elevated for 2-3 hours at KTYS and KTRI, but afterwards expect light winds at all terminals. && .PRELIMINARY POINT TEMPS/POPS... Chattanooga Airport, TN 75 62 86 64 / 70 10 10 60 Knoxville McGhee Tyson Airport, TN 76 61 84 62 / 50 0 0 60 Oak Ridge, TN 73 61 84 61 / 60 0 0 60 Tri Cities Airport, TN 74 58 80 57 / 30 0 0 30 && .MRX WATCHES/WARNINGS/ADVISORIES... NC...NONE. TN...NONE. VA...NONE. && $$ SHORT TERM...Wellington AVIATION...CD ####018004403#### FXUS62 KTBW 180003 AFDTBW Area Forecast Discussion National Weather Service Tampa Bay Ruskin FL 803 PM EDT Wed Apr 17 2024 ...New UPDATE, AVIATION... .UPDATE... Stacked ridging over the region continues to produce subsidence aloft trapping the dry airmass in place over the area. The surface pressure gradient is relaxing as high pressure weakens across the FL Peninsula. Expect more above normal temperatures while humidity remains fairly low then a more pronounced and cooling west coast seabreeze should push further inland Thursday. Latest grids and forecast in good shape. && .AVIATION... (00Z TAFS) VRF conditions continue with mostly clear skies and light/variable winds tonight then bay/seabreeze winds Thursday afternoon. && .DISCUSSION... Issued at 223 PM EDT Wed Apr 17 2024 The dry and stable weather pattern continues as mid level ridging in the Gulf of Mexico and surface high pressure in the Atlantic continues to remain in place. By late week, there will be some flattening of the ridge as a large upper level low drifts across northern Ontario and our flow aloft will transition from northwesterly to more of a westerly (zonal) orientation for the upcoming weekend. Meanwhile, this upper level low in Canada and the associated low pressure system will drive a cold front across the Eastern Seaboard by the weekend and as this occurs, the Atlantic high pressure will shift further offshore with the surface ridge axis setting up to the south of the area. With a gradual uptick in deeper moisture and a mostly WSW flow in place for the weekend, there may be a few light showers that develop in our interior areas as the sea breeze collision occurs over the eastern side of the peninsula. This also seems to be supported by recent guidance showing some potential for light pockets of QPF over the weekend associated with some of this sea breeze activity but for now will hold off on adding any PoPs to the official forecast as confidence still remains low. By late weekend, a southern stream shortwave trough will swing across the lower Mississippi Valley and this will support the development of a surface low around the northern Gulf Coast. This surface low will quickly shift off to the northeast as it moves offshore of the Carolinas and rain chances will increase area-wide as the aforementioned cold front slides southward across the peninsula on Monday. Models then show the frontal boundary sliding south of the area by Monday night with drier air then building into the area as high pressure builds in from the north. While there will also be some slightly cooler air in the wake of the frontal boundary, particularly for the northern half of the area, temperatures are generally expected to remain normal through the end of the extended forecast period as any cold air advection behind the front looks limited at this time. && .MARINE... Issued at 223 PM EDT Wed Apr 17 2024 High pressure in the Atlantic will remain in place through the end of the week, providing warm and dry conditions across the coastal waters and favorable marine conditions. Winds shift to the west-southwest by the weekend as a cold front ahead of a cold front that is expected to arrive by Monday and bring the next chance of rain across the area, but no headlines are expected at this time. && .FIRE WEATHER... Issued at 223 PM EDT Wed Apr 17 2024 Minimum RH values will continue to drop below critical levels through the remainder of the week in inland areas as a dry air mass remains in place, though wind speeds will be light enough to preclude any red flag concerns. Humidity values will finally start to recover by the weekend as winds become southwesterly ahead of a cold front that is expected to arrive by next Monday, which will bring the next chance of rain across the region. && .PRELIMINARY POINT TEMPS/POPS... TPA 67 87 69 87 / 0 0 0 0 FMY 65 87 67 88 / 0 0 0 0 GIF 64 90 66 92 / 0 0 0 0 SRQ 65 87 67 87 / 0 0 0 0 BKV 60 89 61 89 / 0 0 0 0 SPG 69 84 70 84 / 0 0 0 0 && .TBW WATCHES/WARNINGS/ADVISORIES... FL...None. Gulf waters...None. && $$ RJD ####018012667#### FXUS65 KABQ 180003 AAA AFDABQ Area Forecast Discussion...UPDATED National Weather Service Albuquerque NM 603 PM MDT Wed Apr 17 2024 ...New UPDATE, AVIATION... .UPDATE... Issued at 550 PM MDT Wed Apr 17 2024 In conjunction with NWS PUB and AMA, brought the backdoor cold front into the eastern plains during the evening hours rather than late night and early morning hours. Wind gusts around 40 mph are likely tonight around Clayton, where low clouds could obscure the sky by as early as midnight then linger into early Thursday morning. The question is, how far south and west will the low clouds go? It's tough to say, but we do know models are notorious for bringing cool season backdoor cold fronts in too slowly and not progressing them into NM far enough. There is a fair chance that the low clouds will reach Tucumcari and possibly Las Vegas by sunrise, but this update kept them to the north and east of these locations. Also, lowered overnight low temperatures a few degrees across northeast and east central areas due to the faster arrival of the front. Additional forecast updates will be possible as the front begins moving into the state and models get a better handle on it. && .SYNOPSIS... Issued at 206 PM MDT Wed Apr 17 2024 A back-door cold front, initially arriving tomorrow, will interrupt our warm, breezy springtime pattern, especially for areas along and east of the central mountain chain, through Saturday. Cooler temperatures, patchy late night/early morning fog, and light rain are likely behind the front. A moderate east canyon wind is likely Friday night into early Saturday as the front receives a reinforcing push. An upper-level disturbance interacting with the moisture along the front may allow for a few thunderstorms in the central part of New Mexico on Saturday as well. Drier and warming conditions return for the early part of next week, though another back-door front looks to edge into the northeast portion of the state next Monday night. && .SHORT TERM... (This evening through Thursday night) Issued at 206 PM MDT Wed Apr 17 2024 Mostly clear skies tonight with above average temperatures prevailing. A stout upper low touring the US/CAN border will kick a backdoor front down the Great Plains today, with the frontal boundary entering into northeastern NM tonight around 12Z. Gusty northerly winds will accompany this front as it surges southwestward across the eastern plains throughout the day on Thursday. Cooler temperatures will be felt in the front's wake, bringing daytime highs across the eastern plains down 10F to 20F compared to today's readings. Challenge lies in how far the front will progress, but did blend temps to the cooler side of guidance. Elsewhere, a few degrees of warming can be expected amongst sunny to partly cloudy skies. The front will continue surging westward, flirting with the east slopes of the central mts and the chain's gaps Thursday night. A gentle turn to east is likely very late in the night into early Friday morning. Lows across the RGV and westward will be generally unaffected by this frontal spillage. Minimum temps across the central mts and eastward will see a few degrees of cooling to overnight lows compared to Wednesday night's readings. && .LONG TERM... (Friday through Tuesday) Issued at 206 PM MDT Wed Apr 17 2024 The aforementioned back-door cold front temporarily washes out/retreats north and east as S/SW winds re-establish across much of the state by around mid-day on Friday. This should yield another warm spring day, with temperatures topping out 8-12 deg F above normal along west of the central mountain chain, with the far eastern Plains remaining 5-8 degrees below normal. For Friday evening and into the overnight, the back-door front is given a second, stronger push via high pressure building southward in the southern Plains. All indications are that the easterly push will at least reach the central mountains and push through the gaps, with the NAM in particular taking the boundary further west, toward the Continental Divide, on Saturday. Higher confidence impacts are for at least patchy fog and rain across the eastern plains, due to moist upslope flow, with the highest amounts along the Texas border where a few tenths of an inch may accumulate. Also relatively high confidence on at least moderate east canyon winds for the Albuquerque and Santa Fe metro areas. Went above NBM guidance and blended in MOS in these areas, with current forecast indicating easterly winds of 25mph with gusts to around 35mph. Without a well-defined low center in SE Arizona, a stronger east wind is not expected at this time, but will have to watch. More medium confidence on thunderstorm development roughly along the Rio Grande Valley during the day on Saturday. Guidance points to ribbon of MUCAPE values reaching 500-1000 J/kg along and just behind the frontal boundary...though this could end up being west of the Albuquerque metro. Low-level moisture from the east wind, combined with a modest upper-level short-wave trough should be enough to kick off a few thunderstorms where instability permits. Deep-layer shear (easterlies below westerlies) could reach 40-50 knots, but lack of mid-level moisture might be the limiting factor, at least for coverage. Upshot is that mentionable PoP's were pulled westward a bit from NBM guidance into the RGV for Saturday afternoon. Moisture should mostly get scoured out on Sunday, on deeper WNW flow aloft. A few showers may hang on in the northern mountains, however. A warming trend also commences, with 80-degree readings returning to the mid/lower RGV and temps recovering as much as 15-20 degrees from Saturday's highs in the eastern Plains. Rather warm temperatures continue through next Wednesday, as quasi- zonal or SW flow aloft continues. One exception in NE New Mexico where another back-door cold front slips in Monday night. Nil precipitation is expected after Sunday. && .AVIATION... (00Z TAFS) Issued at 550 PM MDT Wed Apr 17 2024 A gusty backdoor cold front will dive southwestward through the eastern plains tonight, accompanied by low clouds producing MVFR conditions that could potentially reach as far south as TCC and west as LVS by sunrise Thursday morning. Confidence was too low to include in the LVS and TCC 00Z TAFs. Otherwise, high clouds will increase tonight, then cover most of the forecast area through Thursday. && .FIRE WEATHER... Issued at 206 PM MDT Wed Apr 17 2024 A backdoor front surging down eastern New Mexico tonight into tomorrow will bring much needed improvement to moisture. The northeast and east central plains will see min RH settle in the 20 to 30 percent range, while zones to west remain critically dry in the low double digit to single digit values. Breezy conditions across northern New Mexico will create elevated to near critical fire weather conditions for the Upper Rio Grande Valley Thursday afternoon. Improved moisture will surge south and westward, bringing slightly greater coverage to the improved min RH on Friday. Unfortunately, highland zones and westward will still remain critically dry, with widespread single digit RH prevailing. Winds will work to limit critical fire weather conditions but elevated to near critical conditions will still prevail across all zones west of the plains. Localized critical fire weather conditions may exist across portions of the east slopes of the Sangre de Cristo Mountains, their adjacent highlands, and the Upper Rio Grande Valley Friday afternoon. Moisture will make another push westward on Saturday, reaching into the Rio Grande Valley, while areas along the Continental Divide and westward continue to see critical dry conditions. Chances for rain and thunderstorms will increase in the afternoon across the eastern plains and along the ridgeline of the Sangre de Cristo Mountains. Good recoveries and increased min RH will hang on through Sunday, before dry air intrudes into the region again, bringing min RH values back into the teens to single digits. && .PRELIMINARY POINT TEMPS/POPS... Farmington...................... 40 78 45 78 / 0 0 0 0 Dulce........................... 33 73 39 75 / 0 0 0 0 Cuba............................ 37 74 42 74 / 0 0 0 0 Gallup.......................... 33 76 35 76 / 0 0 0 0 El Morro........................ 37 72 39 73 / 0 0 0 0 Grants.......................... 33 76 36 76 / 0 0 0 0 Quemado......................... 37 76 39 76 / 0 0 0 0 Magdalena....................... 45 78 49 78 / 0 0 0 0 Datil........................... 40 75 43 75 / 0 0 0 0 Reserve......................... 34 79 38 80 / 0 0 0 0 Glenwood........................ 46 82 52 83 / 0 0 0 0 Chama........................... 33 67 37 68 / 0 0 0 0 Los Alamos...................... 46 72 46 72 / 0 0 0 0 Pecos........................... 39 73 38 73 / 0 0 0 0 Cerro/Questa.................... 39 67 40 68 / 0 0 0 0 Red River....................... 32 63 32 64 / 0 5 0 0 Angel Fire...................... 27 64 27 65 / 0 0 0 0 Taos............................ 33 73 35 73 / 0 0 0 0 Mora............................ 37 71 35 72 / 0 0 0 0 Espanola........................ 41 80 45 81 / 0 0 0 0 Santa Fe........................ 44 74 45 74 / 0 0 0 0 Santa Fe Airport................ 40 77 43 78 / 0 0 0 0 Albuquerque Foothills........... 51 79 51 81 / 0 0 0 0 Albuquerque Heights............. 47 81 50 82 / 0 0 0 0 Albuquerque Valley.............. 46 84 49 84 / 0 0 0 0 Albuquerque West Mesa........... 47 83 49 82 / 0 0 0 0 Belen........................... 45 85 47 86 / 0 0 0 0 Bernalillo...................... 47 82 48 83 / 0 0 0 0 Bosque Farms.................... 44 84 47 84 / 0 0 0 0 Corrales........................ 46 83 48 83 / 0 0 0 0 Los Lunas....................... 44 84 47 84 / 0 0 0 0 Placitas........................ 48 79 49 78 / 0 0 0 0 Rio Rancho...................... 47 82 49 83 / 0 0 0 0 Socorro......................... 48 86 51 88 / 0 0 0 0 Sandia Park/Cedar Crest......... 46 73 45 73 / 0 0 0 0 Tijeras......................... 46 76 45 75 / 0 0 0 0 Edgewood........................ 43 76 42 78 / 0 0 0 0 Moriarty/Estancia............... 37 78 37 79 / 0 0 0 0 Clines Corners.................. 40 73 38 73 / 0 0 0 0 Mountainair..................... 44 77 43 78 / 0 0 0 0 Gran Quivira.................... 44 77 43 78 / 0 0 0 0 Carrizozo....................... 50 81 52 82 / 0 0 0 0 Ruidoso......................... 47 76 48 74 / 0 0 0 0 Capulin......................... 36 62 34 67 / 0 5 0 0 Raton........................... 35 71 33 74 / 0 5 0 0 Springer........................ 37 72 36 75 / 0 5 0 0 Las Vegas....................... 41 71 37 73 / 0 0 0 0 Clayton......................... 40 59 35 67 / 0 0 0 0 Roy............................. 43 66 38 71 / 0 0 0 0 Conchas......................... 43 73 43 78 / 0 0 0 0 Santa Rosa...................... 44 77 43 75 / 0 0 0 0 Tucumcari....................... 44 69 41 72 / 0 0 0 0 Clovis.......................... 45 74 44 69 / 0 0 0 0 Portales........................ 44 76 44 70 / 0 0 0 0 Fort Sumner..................... 46 81 45 76 / 0 0 0 0 Roswell......................... 51 91 52 80 / 0 0 0 0 Picacho......................... 51 85 47 80 / 0 0 0 0 Elk............................. 49 84 46 80 / 0 0 0 0 && .ABQ WATCHES/WARNINGS/ADVISORIES... None. && $$ SHORT TERM...44 LONG TERM....53 AVIATION...44