Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 11/04/24


Area Forecast Discussion
National Weather Service Denver/Boulder CO
302 PM MST Sun Nov 3 2024 .KEY MESSAGES... - A low pressure system will bring accumulating snow and cold temperatures late today through midday Monday. Moderate snow will fall across the higher terrain with impacts to travel, especially during the Monday morning commute. 0.5-3" of snow is forecast for the Denver metro with the Monday morning commute seeing the brunt of the impacts. - Ample uncertainty beyond Tuesday for a potential longer period of unsettled weather across much of the region. - Could we see two to three distinct waves of winter weather Wednesday into the weekend, yes, but confidence is low on how significant impacts will be at this time. && .SHORT TERM /Through Monday/... Issued at 213 PM MST Sun Nov 3 2024 Radar shows snow showers have developed over the mountains this afternoon as a 500 mb trough approaches the region. Looking at webcams, we can see that roads remain wet at this time, however, this is expected to change as temperatures lower this evening and snow levels drop below 5000`. Rain is expected for our foothills and urban corridor this evening before transitioning to snow by the early morning. Snowfall accumulations are expected to remain mainly west of I-25 and south of I-76, with the highest accumulations expected south of Denver where northerly surface flow offers the best orographics. With the hi-res models showing a steady uptick in QPF throughout the morning for areas including the Indian Peaks and Mummy Range, we have decided to upgrade our Winter Weather Advisory to a Winter Storm Warning for these locations as heavy snow will be possible at times that may make travel very difficult. Accumulations of more than a foot will be possible in areas of heaviest snowfall. On top of the Winter Weather Advisory already in place for our foothills locations where an additional 3 to 6" of snowfall are expected overnight, we have gone ahead and issued an additional Winter Weather Advisory to include the Palmer Divide where up to 4" of snow are forecast and expected to bring impacts to the Monday morning commute. The snow is expected to taper off by late Monday morning as the trough axis pushes east. Flow aloft will transition to northwesterly by the evening, resulting in mostly clear skies and dry conditions for the overnight hours. && .LONG TERM /Monday night through Sunday/... Issued at 213 PM MST Sun Nov 3 2024 ...Continuing to see signs of a prolonged cold and snowy period from Wednesday through Saturday... Tuesday (Election Day) looks like the last high confidence forecast day for a while, with Colorado in between storm systems. The next major player in our forecast the rest of the week is a strong short wave trough digging south out of western Canada on Tuesday. The trough will be heavily influenced by a >150 kft jet on the backside, which will drive it rapidly to the south. Lift from the trough holds off until Wednesday, but there is increasing west flow aloft, and with a little moisture working in, light snow may begin as early as Tuesday morning in the northern mountains, then spread to the rest of the mountains by Tuesday afternoon and evening. Moisture is lacking and lapse rates above ridge top are weak, so expect amounts on Tuesday to be on the light side. It will also be windy across the Divide and east slopes during the middle of the day with 40+ kts of cross barrier flow and a weak inversion between 600-500 mb. There is a little subsidence in the wake of the departing trough such that we expect mountain wave enhanced winds to descend the east slopes a bit. With that mountain wave enhancement, we have increased the winds for the foothills but for now are keeping the higher winds out of the adjacent plains into Tuesday afternoon. Gusts to 50 mph are possible across the higher foothill locations. Downslope flow across the plains should result in highs in the 50s, while ample cloud cover and slowly cooling temperatures aloft mean the mountain valleys should remain in the 30s. With the "easy" day out of the way, attention turns to the overly complicated forecast Wednesday through Saturday. The last long term discussion used song lyrics to frame the discussion, so why not do that again but this time with a hit song a year earlier than Bonnie Raitt`s hit: "Things That Make You Go Hmmm" by C+C Music Factory. We think we lost count with how many things are making us go hmmm in the forecast from Wednesday through Saturday. We wish we could say confidence is increasing with time, but that is simply not the case. There are some broad brush aspects of how the cut off trough could evolve, but the problem is that small changes in the position and movement of the trough make massive differences in the snow amounts and travel impacts across our area. The current forecast has the 500 mb trough digging south on Wednesday to somewhere from southeast Utah to western Colorado. It is extremely positively tilted on Wednesday into Thursday, which will cause it to cuts off from the main trough across southern Canada on Thursday. Since it will be cut off from the polar jetstream, the trough will slowly wobble eastward Thursday and Friday. Ensemble guidance has the trough moving slowly from the Four Corners, then across northern New Mexico, then ejecting it northeast into NE Colorado or NW Kansas by early Saturday morning. There are well established sweet spots in the location of the 500 mb and 700 mb troughs for heavy snow across our area that are very much in play, but given there is little agreement on the position/location among models and among their ensemble members, confidence in how this is actually going to play out is very low at this point. Given the uncertainty, here is what we think could happen. A cold front is expected to move across the plains of Colorado late Tuesday into early Wednesday, and snow should develop associated with increasing frontogenesis aloft Wednesday morning. Banded snowfall could briefly be moderate and could impact the morning commute. Plenty of synoptic lift and instability is expected to be in place across the western half of Colorado Wednesday morning, especially with a trough placement along the Utah/CO border. Thus, mountain snow should also ramp up Wednesday morning, though upslope is very weak in the mountains with flow turning southeast at ridge top as the trough moves south into the Four Corners area. The QG lift goes south with it, and sometime in the late evening mountain snow showers may weaken or shut off, through some models keep it going Thursday and Friday with the trough close enough to continue providing a source of lift and instability. That`s definitely a thing that makes us go hmmm, and something we`ll continue to monitor. For now, if it does snow in the high country much of Thursday and Friday, it will most likely light snow that adds up to fairly impressive three day totals. With the trough sinking south, the best snowfall would be favored along and south of I-70 in our mountains through Friday. Temperatures will remain below freezing above 8 kft throughout the period, thus there is potential for slick roads throughout the period as well, though with lighter snow rates perhaps the impacts will be more limited after Wednesday. For the plains, snow is likely to fall much of Wednesday with plenty of lift and instability from the trough, 25kt of east upslope flow at 700 mb, and low-level northeast flow. In that type of pattern the most snow would fall along the Palmer Divide and along the foothills from Boulder County southward. Slick roads are certainly possible for metro Denver/Boulder Wednesday morning and again in the evening after sunset, with the highest chances of slick roads for the foothills west of Denver/Boulder and the Palmer Divide. Northern parts of the plains may not see much snow Wednesday since they will be fighting the downslope off the Cheyenne Ridge. Thursday and through half of Friday, the near-surface flow should be northerly across the plains and depending on the location of the trough, the best forcing would be across southern Colorado. The best bet is for a cool/cold, mostly cloudy day across most of the Plains, though there could be accumulating snow south of I-76, especially along and east of the Palmer Divide (another thing that makes you go hmmm). Obviously if the trough is further north light snow could fall much of the day Thursday into Friday across the I-25 urban corridor, but for now the official forecast has the highest snow chances across the Palmer Divide eastward to Kansas Thursday into early Friday. Easily the latest development in the forecast that makes you go hmmm is Friday into Saturday if current model trends become reality. As the trough moves east, it should encounter a boatload of Gulf of Mexico moisture and a nice thermal gradient oriented SW to NE across the High Plains which would force the trough to lift northeast with a strengthening jet on the east side of the trough. The latent heat release and temperature gradient could cause the trough to rapidly deepen. A trough that intensifies that much and that quickly will have an extensive TROWAL/wrap around region of precip northwest of the bowling ball trough, and if the trough moves from SE Colorado into NW Kansas, that wrap around intense band of precip would be comprised of heavy snow across north central Colorado. All models are now hinting that the cut off trough could rapidly deepen and become negatively tilted later Friday into Saturday, but the heavy snow and travel impacts are tied to the position of the trough and the how much it intensifies. It`s way to early to say with any confidence where that might occur, and how strong it might become. Ensemble cluster analysis, usually enlightening, isn`t much help yet with this potential outcome. Every cluster has the cut off trough lifting northeast, some have it deeper, some have it lifting faster, but at this point all options are on the table from a heavy, high impact snow on the high end, to cold with flurries on the low end, and equally low chances of anything in between. Freedom Williams could write a great rap about this forecast and add it as a verse to his hit song. Much more to come as we get closer to the end of the week. && .AVIATION /18Z TAFS through 18Z Monday/... Issued at 1042 AM MST Sun Nov 3 2024 An approaching winter storm is expected to impact the Denver area TAF sites tonight through Monday morning. Rain is expected to transition to snow around midnight tonight, with ceilings dropping to MVFR by roughly the same time. Hi Res models are starting to back off slightly on snowfall amounts at KDEN at this time, with a trace to 1" forecasted for DEN and 1-3" for KBJC and KAPA. There may be a period of .5"/hour of accumulations at the time of heaviest snowfall, likely between the 7Z to 10Z time frame. Visibilities may drop as low as 2 miles at KDEN, with a brief period of .5 to 1 mile vis possible at KBJC and KAPA. There is a chance that ceilings drop to LIFR for a short time while visibilities are at their lowest. Conditions are expected to improve quickly after snowfall clears out, with MVFR expected to scatter out by the 19Z to 20Z time range. && .BOU WATCHES/WARNINGS/ADVISORIES... Winter Weather Advisory until 11 AM MST Monday for COZ031. Winter Storm Warning until 11 AM MST Monday for COZ033-034. Winter Weather Advisory from 8 PM this evening to 11 AM MST Monday for COZ035-036-041. && $$ SHORT TERM...Bonner LONG TERM...Schlatter AVIATION...Bonner
Area Forecast Discussion
National Weather Service Burlington VT
939 PM EST Sun Nov 3 2024 .SYNOPSIS... A warm front arriving on Monday will bring warming temperatures through the middle of the week. Next chance for showers will come mid week as a surface cold front crosses the area and brings temperatures back down closer to normal. && .NEAR TERM /THROUGH TUESDAY/... As of 934 PM EST Sunday...Based on radar trends and latest 00z data from the NAM 3KM/HRRR and RAP I have increased pops acrs the SLV/northern NY after midnight and into Monday morning. This also increases the potential for patchy freezing rain/mixed precip during the Monday morning commute, especially the northern SLV near KMSS where the crnt temps is 26F. Also, a few slick spots possible in the deeper/protected valleys of the northern Dacks. Greatest potential for freezing rain/mixed precip is roughly from 09z-14z Monday. The qpf wl be light and only a few hundredths of an inch, as lowest 5000 feet is fairly dry and expecting some virga to occur as precip advects into dry air from departing sfc high pres. A light glaze is possible in a few locations acrs northern NY on Monday morning associated with the very light wintry mixed precip. Rest of fcst in good shape. Previous discussion below: Surface and upper level ridging remain in place overnight, keeping the region dry. Will have some high clouds in place and moving into the area from the west ahead of an approaching warm front. Temperatures will still drop pretty sharply despite the high thin clouds, minimum temperatures will reach the 20s areawide. Pretty dry air in place should help prevent any showers from reaching the ground. On Monday our region will be under warm air advection and southerly flow. Maximum temperatures will reach the mid 40s to around 50 degrees. Winds will increase in the afternoon and continue into the overnight with tightened pressure gradient in place. Temperatures on Monday night will not cool very much at all, maybe just a few degrees. Chance for showers ill increase along our northern border Monday afternoon into the overnight. Precipitation Monday night will be light with two tenths of an inch or less expected. && .SHORT TERM /TUESDAY NIGHT/... As of 354 PM EST Sunday...Biggest question marks for this period may be related to cloud cover. A weak shortwave embedded within the upper level flow will still be tracking over the area while large scale lift occurs in the low levels with continued warm air advection. This pattern typically leads to low clouds. Shower chances will be highest over northern portions of our region where cloudy skies are the surest bet into the morning hours. Have leaned towards a blend of the latest deterministic model guidance suggesting overcast skies through the first part of the day, trending partly cloudy from south to north late as drier air aloft helps scatter out some clouds. As such, high temperatures across the board are trending a bit less warm. However, the southerly flow will undoubtably help boost temperatures even with limited sunshine. Temperatures should reach into the 60s with with dew points returning into the 50s by afternoon in most locations. Areas within the St. Lawrence Valley are most likely to reach 70 degrees. Surprisingly, record high temperatures are unlikely, in part due to a very warm November 5th just two years ago. More interesting will be overnight temperatures, as the combination of an unusually strong 850 millibar southwesterly jet and rich moisture will keep temperatures very mild Tuesday night. Temperatures will remain well into the 60s overnight in the wide valleys with mainly mid and upper 50s elsewhere. With low pressure tracking so far to the northwest, frontal forcing for precipitation will remain outside of the area until possibly the very light night period as a plume of deeper moisture arrives from the west. So precipitation chances ramp up quickly after 2 AM, and become near 50-60% over most of northern New York besides the Champlain Valley and far northern Vermont/northern Greens with lower chances elsewhere. Chances of rain will increase into Wednesday. Forecast soundings show anomalous moisture but lack of instability with poor lapse rates throughout the column of air. Jet dynamics are also unfavorable for enhanced precipitation with a weakening upper level jet streak still back to the west. So rainfall will be on the lighter side, mainly under 0.1" through this period. && .LONG TERM /WEDNESDAY THROUGH SATURDAY/... As of 354 PM EST Sunday...Wednesday will be a transition day into a different weather pattern for the late week and weekend as upper level flow shifts from southwesterly to northwesterly. The potential for impactful wind on Wednesday has diminished slightly with this forecast cycle, but gusty post-frontal winds are expected, especially across the Adirondacks and central/eastern Vermont where better mixing looks most favored at this time. Dew points will fall greatly later Wednesday into Thursday due to surface winds turning northwesterly. Fire weather will be the main potential impact for this period, as relative humidity will be trending lower and breezy westerly winds will be possible, particularly on Friday when a pressure gradient will increase with high pressure to our south and low pressure passing to our north. Subtle frontal boundaries from the north will pass through such that temperatures will trend cooler through Saturday. Next real chance of rain doesn`t seem to come until Sunday, but there is large uncertainty in timing and storm track of the next system that could approach from the west. && .AVIATION /03Z MONDAY THROUGH FRIDAY/... Through 00Z Tuesday...VFR conditions are expected to prevail across all terminals for the next 24 hours. Despite light winds and thin, high clouds early tonight, dry conditions are expected to prevent much fog from occurring overnight. Later in the night, increasing thicker high to mid level clouds will put a cap on radiational cooling and any potential radiational fog production. Winds will return out of the south/southeast tomorrow morning at 5-10 knots, except at MSS, which will likely have a more northeasterly wind direction. Winds will be increasing at the surface and also aloft tomorrow afternoon, resulting in southerly gusts 15-20 knots at BTV and LLWS expected for SLK, MPV, EFK, and MSS 17Z-22Z onward. Outlook... Monday Night: Mainly VFR, with local MVFR possible. Chance SHRA. Tuesday: Mainly VFR, with local MVFR possible. Slight chance SHRA. Tuesday Night: Mainly VFR, with local MVFR possible. Chance SHRA. Wednesday: Mainly VFR, with areas MVFR possible. Chance SHRA. Wednesday Night: Mainly VFR, with local MVFR possible. Slight chance SHRA. Thursday: Mainly VFR, with local MVFR possible. NO SIG WX. Thursday Night: VFR. Slight chance SHRA. Friday: Mainly VFR, with local MVFR possible. NO SIG WX. && .BTV WATCHES/WARNINGS/ADVISORIES... VT...None. NY...None. && $$ SYNOPSIS...Neiles NEAR TERM...Neiles/Taber SHORT TERM...Kutikoff LONG TERM...Kutikoff AVIATION...Storm
Area Forecast Discussion
National Weather Service Dodge City KS
446 PM CST Sun Nov 3 2024 .KEY MESSAGES... - Two major storm systems to impact the southwest Kansas region through next Saturday. - Storm #1 will provide large area of cold rain much of the day Monday with widespread 1/2 to 1" rainfall likely. - Storm #2 later in the week will also be a very wet storm across much of the central and southern High Plains. Early indications are widespread additional 1-2" of rainfall highly possible based on latest ensemble 25th-75th percentile output. && .DISCUSSION... Issued at 345 PM CST Sun Nov 3 2024 A very active weather pattern will continue through this forecast period ending next weekend. Two Southwest Lows will move out across the Great Plains, each of which bringing appreciable rainfall across our southwest Kansas region. This afternoon water vapor imagery and RAP analysis showed the center of a deep mid tropospheric trough axis extending from Montana south to eastern Arizona. The strongest upper level jet streak was still on the western side of the trough axis, thus deepening and closing off of a mid latitude cyclone has yet to occur and will occur tonight as the base of the trough moves out across New Mexico. By 18Z Monday, models have aligned fairly well with 500mb low centered somewhere between Roswell and Clovis, NM with south to north 500-700mb upstream of southwest Kansas, interacting with a low level front which will be moving slowly south during the day Monday. Abundant low level moisture will continue in the warm sector south of the front from the eastern Texas Panhandle into Oklahoma, and widespread rain will overspread southwest Kansas in the 12-15Z time frame Monday. The classic "comma head" of the maturing mid-latitude cyclone will occur over southwest Kansas with fairly rapid occlusion occurring mid to late day Monday as the mid level jet streak rounds the southeastern portion of the cyclone. Frontogenesis centered around 700mb will increase from southwest to northeast from roughly Liberal to Dodge City to Hays, becoming quasi-stationary through the afternoon into the evening. This will likely be the axis of heaviest rainfall amounts. 12z HREF has a large area of 25-75th percentile rainfall amount range of 0.50 to 1.00". So, we have fairly high confidence, both from forecaster experience of lows tracking to the south of southwest Kansas like this, and from the model QPF fields in a large portion of southwest Kansas seeing 1/2 to 1" of rain. Some isolated peak amounts of 1.50 to 1.75" cannot be ruled out in some portions of southwest Kansas, near the zone of strongest frontogenesis, based on 90th percentile HREF fields. This event will be all cold rain, although HREF does show some small probSnow along the Colorado line, however given the spatial extent of probSnow tied just to the Colorado line, we will keep all areas liquid rainfall. Areas like Elkhart to Manter could see a couple wet snow flakes mixed in during heavier precipitation. Most areas, especially west of U283, will stay in the 40s during the afternoon with the widespread rain and north surface winds. The storm will pull away late in the evening Monday as it also weakens, so rainfall rates will drop quite a bit in the 06-09Z time frame early Tuesday morning. Tuesday will be quiet in between storm systems with light wind and an MSLP pattern readjusting between the departure of Monday`s storm and the approach of mid-late week storm. By Tuesday Night and Wednesday, the next upper low will form across southern Utah toward the Four Corners. This system will start off more negatively tilt, which will allow the next round of colder air and north winds to drive south ahead of the system. All the models and ensemble system show the upper low anchoring and changing orientation from positive tilt to neutral to eventually slight negative tilt as the cyclone traverses the Southern Rockies. Low level moisture will begin to push back northwest into the southern High Plains (large area of 12+ degC 850mb dewpoint). The 850mb response looks quite good on all models with strong southeasterly winds at that level of 30 to 40 knots by late Thursday/Thursday Night. This will manifest as a large area of showers and thunderstorms just to the south of southwest Kansas with low level moisture transport vectors pointed right toward southwest Kansas. This is shaping up to be an even more meteorological impressive storm for much of the southern and central High Plains, including southwest Kansas, and it really will come down to timing and the number of rounds of moderate to potentially heavy rainfall. Right now, much of our area will likely see heaviest rainfall from late Thursday Night into Friday Night. Latest 100-member Grand Ensemble from 12Z this morning shows 25th- 75th percentile range of 1-2" for the event total with Storm #2 at DDC over the period Thursday through early Saturday. There will be much more concerning the late week to early weekend storm as we draw closer to this event, so keep checking back for updates. && .AVIATION /00Z TAFS THROUGH 00Z TUESDAY/... Issued at 441 PM CST Sun Nov 3 2024 Low clouds will once again envelop western Kansas overnight with MVFR to IFR ceilings by sunrise tomorrow. Periods of showers after 12Z tomorrow may lower visibilities to LIFR conditions. Winds will initially be from a southerly direction, shifting to the north with an increase in speed by sunrise tomorrow. Wind gusts should remain below 25 knots late morning into the afternoon. && .DDC WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION...Umscheid AVIATION...Hovorka_42
Area Forecast Discussion
National Weather Service Goodland KS
620 PM MST Sun Nov 3 2024 .KEY MESSAGES... - An isolated severe storm capable of producing quarter size hail and/or wind gusts up to 60 mph remains possible over portions of Gove, Sheridan, Graham and Norton counties through 11 pm CST this evening. - Good chance (30%-70%) for rainfall on Monday. - Rainfall/snowfall chances Tuesday night-Friday night. && .SHORT TERM /THROUGH MONDAY/... Issued at 253 PM MST Sun Nov 3 2024 This afternoon we are monitoring a cold front currently moving over the Tri-State borders into Northwest Kansas. The dryline moved over the Goodland ASOS about two hours ago which was a little sooner than anticipated. This has led to a decrease in confidence for severe weather over the western half of the area and the current shape of the SPC Marginal risk area. We do have some showers near the Kit Carson and Lincoln county border that have struggled to mature and appear to be getting sheared out by the ~60 kts of surface to 6 sm shear. SPC Mesoanalysis and RAP guidance shows the best Surface- based CAPE (SBCAPE), ~1,000 J/kg, nosing northeast into the area from roughly Pueblo, Colorado into Nebraska. As we move into the evening, instability will be favored mainly along and east of Hwy 83. If that corridor of instability can remain long enough for the cold front to interact with it, we should be able to see some isolated to scattered storms develop and move north-northeast. The best window for severe weather is currently 4 PM to Midnight (12 AM) MST/ 5 PM to 1 AM CST. The NAMnest has had the best resolution so far with the activity coming off the Palmer Divide, so the forecast leans more into that model. All hazards remain possible for Northwest Kansas and extreme Southwest Nebraska with concerns for up to ping pong ball sized hail, 60 mph damaging wind gusts, and a tornado or two can`t be ruled out. Rain will stick around behind the cold front into Monday evening as it moves in from the south. Over the next 24 hours, it`s possible some areas along our eastern edge could see up to 0.5" of rain. Some light snow could mix in with the rain west of Highway 385 tonight. However, little to no accumulation is expected given the warm soil temperatures. Overnight lows will be in the 30s over the western half of the area and in the lower 40s over the eastern half. Temperatures on Monday will be a bit cooler than today with highs in the 40s to lower 50s. Overnight lows will be in the 20s to lower 30s. && .LONG TERM /MONDAY NIGHT THROUGH SUNDAY/... Issued at 119 PM MST Sun Nov 3 2024 The long-term looks to be very unsettled with the potential for some beneficial precipitation to occur. Monday night we will see precipitation leaving the area to the southeast as a trough extending into Mexico is pushed to the northeast. Lows will cool into the upper 20s to lower 30s as the precipitation ends. There could be a mix of rain and snow at the tail end of the precipitation, too. Tuesday will see a shortwave ridge move into the area, clearing out the area and allowing us to warm into the upper 50s before another trough impacts the area, starting Tuesday night, starting an active pattern for the remainder of the period. What will make this pattern so active is a trough descending over the Great Basin, eventually becoming a closed low over the Four Corners region on Thursday. This will merge the Sub- Tropical and Polar jet streams over the Great Plains down to the southeast CONUS. This positioning of the jet will allow a lee low to form and likely linger around the Tri-State area. Guidance is coming together to show the 850mb low will form over southeastern CO on Wednesday, meander around Texas and Oklahoma for most of Thursday, before moving north through KS. When the low moves is a big question. The GFS has the low moving into Nebraska by Friday mid-day and lingering around southern Nebraska for the rest of the period. The ECMWF and CMC-NH show the low moving north late Friday and into Saturday. If the GFS is correct, we will likely see less precipitation overall due to becoming dry slotted. This would clear out the skies and allow us to warm up a bit more on Friday and Saturday, likely into the 50s and maybe 60s. If the ECMWF or CMC-NH is correct, we can expect more precipitation falling in the CWA. This will be thanks to the low wrapping around moisture into the area. This will also keep temperatures notably cooler with persistent cloud cover and northerly winds providing CAA until the low moves north. For the precipitation, it is far too early to estimate exactly how much locations will receive, but a couple of points are sticking out. We will have our heaviest and best chances for precipitation when the low is traversing around the CWA. Meaning early Wednesday when the low forms and begins to move south, and again when the low moves north into Nebraska. The time inbetween will be stratiform rain that will generally be light. We are also expecting mixed precipitation to occur. Rain is expected in the east, where temperatures will be warmer with snow becoming more likely in the western CWA. The line of where snow will begin to mix in is impossible to pinpoint right now, but it will likely waiver in between highways 385 and 83. Temperatures Thursday morning are expected to be the coldest in this period due to the fairly efficient CAA. Temperatures in the far western CWA could drop into the lower 20s while the rest of the CWA will cool to under 30F. Wind chills in the far west could drop into the lower teens Thursday morning, too. We could be spared the coolest temperatures if the CAA is a bit weaker as the clouds would insulate us and the winds would keep the PBL mixed. A ridge will eventually build in from the southwestern CONUS and push the low pressure system out of the area. This will cease precipitation and allow temperatures to warm a few degrees. List of acronyms: NBM - National Blend of Models GFS - Global Forecast System ECMWF - European Centre for Medium-range Weather Forecasts CMC-NH - Canadian Meteorological Centre-Northern Hemisphere CAA - Cold Air Advection PBL - Planetary Boundary Layer F - Fahrenheit QPF - Quantitative Precipitation Forecast MPH - Miles Per Hour mb - Millibar kts - Knots km - Kilometer CWA - County Warning Area CONUS - CONtiguous United States KS - Kansas CO - Colorado && .AVIATION /00Z TAFS THROUGH 00Z TUESDAY/... Issued at 600 PM MST Sun Nov 3 2024 GLD: VFR conditions are anticipated to prevail overnight. MVFR ceilings will develop late Monday morning (~16-19Z) and persist for much of the afternoon.. before scattering out to VFR by sunset. Northerly winds at 10-15 knots this evening will increase to 20-30 knots after midnight (~06-08Z) and persist through the duration of the TAF period. MCK: VFR conditions are anticipated to prevail through the majority of the TAF period. While a period of MVFR ceilings (~2,500 ft AGL) is possible Monday afternoon, it`s possible that ceilings may remain in low-VFR territory (~3000-4000 ft AGL). Northerly winds at 10-15 knots this evening will increase to 15-25 knots by sunrise (~11-14Z) and persist through the duration of the TAF period. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...None. CO...None. NE...None. && $$ SHORT TERM...KMK LONG TERM...CA AVIATION...Vincent
Area Forecast Discussion
National Weather Service Indianapolis IN
922 PM EST Sun Nov 3 2024 .KEY MESSAGES... - Warmer than normal temperatures expected through next weekend - Chances for rain through Monday, focused over the northwest half of central Indiana - Near record warmth Monday-Tuesday ahead of possibly more widespread showers Tuesday/Tuesday night && .FORECAST UPDATE... Issued at 921 PM EST Sun Nov 3 2024 - Mild and Cloudy overnight. - Chances for light rain west. Surface analysis this evening shows strong high pressure in place over New England. Deep low pressure was found across the Central Plains states. This resulted in Indiana being caught between the two systems, with a warm and mild SE-S flow in place. Water vapor imagery continues to show a large plume of moisture stretching across the southern and central Plains stretching northeast to the Great Lakes. Radar mosaics show abundant precipitation beneath this plume, mainly over MO/AR/E OK and E KS. Dew points across the area remained rather high, in the upper 40s to middle 50s. Overnight the strong surface high to our east looks to continue to block quick eastward progress of the moisture. The highly amplified upper pattern shows a similar slow progression east. This will keep the continued mild and southerly flow in place across Central Indiana through the night. The previously mentioned area of rain showers are expected to push northeast within the flow, arriving in the far western parts of central Indiana during the overnight hours. HRRR depicts this well, showing arrival within the Wabash valley near 09Z, with continued progression northeast. This keeps most the remainder of Central dry overnight. A stray sprinkle cannot be ruled out during the overnight hours. Thus will keep some pops included late overnight across the west, with minimal to no pops across the east, but perhaps a sprinkle mention. Regarding temps, warm southerly flow looks to remain in place. This along with cloud cover will make for a mild night. Temperatures should remain rather steady state or just fall slightly overnight. Look for lows in the upper 50s to lower 60s. && .SHORT TERM (This evening through Monday)... Issued at 239 PM EST Sun Nov 3 2024 Rest of This Afternoon... Mid level clouds covered all but far eastern sections of central Indiana early this afternoon. radar shows some light rain/sprinkles across eastern Illinois, moving into far northwestern portions of the forecast area. The initial round of isentropic lift that was producing the light rain early this afternoon will continue to push northeast. Will keep some chance PoPs northwest with some slight chance PoPs or a sprinkles mention farther southwest. Any rain that falls will help moisten the lower layer of the atmosphere. Warm temperatures in the 60s and lower 70s will continue. Tonight... Weaker isentropic lift will continue this evening, but lift will increase overnight as the low level jet increases. The jet will also bring in moisture. Southerly surface winds will bring in additional moisture for the low levels. The flow aloft will continue to allow warm and moist flow across Indiana and the TAF sites. Mainly mid cloud ceilings are expected, resulting in VFR Conditions. A moderate LLJ, over 40 knts pushing through the Wabash Valley, will pass across the area tonight. This could result in some LLWS due to speed. Some MVFR ceilings are possible on Monday as a wave of forcing arrives during the late morning hours producing showers and some lower cigs. As the forcing departs by mid Monday afternoon, showers will end, but VFR Cigs will remain. Believe there will be enough forcing and moisture to go likely category or higher PoPs by late tonight in the far northwest, with lower PoPs to the southwest where forcing will be weaker. Southerly winds plus cloud cover will keep temperatures unseasonably warm for lows, with low temperatures around 60 to the lower 60s. Monday... Similar conditions will continue on Monday. 850mb winds will be around 50kt. Decent moisture will be around thanks to continued southerly flow. Isentropic lift will continue, but the approach of the left exit region of an upper jet will bring additional forcing, especially to the northwest forecast area. Will once again go with likely or higher category PoPs across portions of the northwest, with lower PoPs to the southwest (farthest from the forcing). With a warm start, temperatures may reach the lower to perhaps middle 70s for highs. If clouds are thicker and/or rain more widespread, readings will top out cooler. Even in that scenario readings will be well above normal. && .LONG TERM (Monday night through Sunday)... Issued at 239 PM EST Sun Nov 3 2024 Monday Night through Tuesday Night... An impressive 1036mb high over the southern Appalachian Mountains will tighten the pressure gradient Sunday night through Monday as a short wave pushes in from the west. This will create blustery conditions with strong WAA into the Midwest and Ohio Valley regions. Dry antecedent surface air will inhibit moisture transport some, but this WAA should result in widespread cloud cover Monday night, with isolated light showers possible. The combination of widespread cloud cover and strong southerly WAA will lead to well above normal temperatures Monday night. In fact, the overnight low Monday night is likely to remain higher than the average high for early November! We are also on Max-Min record watch with the monthly record maximum low of 63F and the forecast low on Monday night of 63F. Ensemble members are trending towards a weakening low pressure system as this shortwave reaches the Ohio Valley on Tuesday. This is likely due to the wave remaining positively tilted in the WAA regime. The weakening of the low will limit moisture transport/convergence on Tuesday along a passing cold front, reducing overall QPF expectations for central Indiana. This will also keep the bulk of cold air aloft to the west, creating weak mid level lapse rates and lessening thunder probabilities. Still, a band of weak to moderate showers are expected to pass through central Indiana midday Tuesday through Tuesday evening; current QPF expectations are between 0.15" and 0.40" with this frontal passage Wednesday through Saturday... Despite the cold front label from Tuesday, the air mass behind this system will remain mild due to continued shortwave development over the Plains, causing a the lack of connection with the cold air over the Canadian Rockies`. This will keep 850mb temperatures in the upper single digits(C), resulting in above normal highs through the extended. These aforementioned shortwaves shouldn`t have much of an impact to central Indiana, as high pressure will remain strong just to our S/E. Any impact from these shortwaves will likely be in the form of periods of increased cloud cover and isolated showers. && .AVIATION (00Z TAF Issuance)... Issued at 623 PM EST Sun Nov 3 2024 Impacts: - Gusty winds through the period. - Non-convective low level wind shear tonight, mainly at BMG - Chance for MVFR ceilings at KLAF on Monday Discussion: Southwest flow aloft will continue to allow warm and moist flow across Indiana and the TAF sites. Mainly mid cloud ceilings are expected, resulting in VFR Conditions. A moderate LLJ, over 40 knts pushing through the Wabash Valley, will pass across the area tonight. This could result in some LLWS due to speed. Some MVFR ceilings are possible on Monday as a wave of forcing arrives during the late morning hours producing showers and some lower cigs. As the forcing departs by mid Monday afternoon, showers will end, but VFR Cigs will remain. && .IND WATCHES/WARNINGS/ADVISORIES... None. && $$ UPDATE...Puma SHORT TERM...50 LONG TERM...Updike AVIATION...Puma
Area Forecast Discussion
National Weather Service Jacksonville FL
827 PM EST Sun Nov 3 2024 ...New UPDATE... .UPDATE... Issued at 820 PM EST Sun Nov 3 2024 For the latest NE FL and SE GA Daily Key Messages please visit: https://www.weather.gov/media/jax/briefings/nws-jax-briefing.pdf Strong high pres continues over New England area with a long fetch of easterly low level flow over the western Atlantic toward our area. Slight troughing in the low levels near the coast and fairly high moisture up through about 8500 ft is helping to maintain a chance of showers for mainly the eastern zones and the marine waters. We note from 00z Sounding that PWAT is now up to about 1.5 inches compared to near 1 inch at 12z. Expect that the shower activity will be more confined to about the first 2 tiers of coastal counties later tonight as the airmass stabilizes further inland. Still, some sprinkles could spread further inland later tonight, mainly in southeast GA where higher moisture will be located. Boundary layer winds appear to be a bit too strong for much of any patchy fog for inland areas. Min temps will be held to the 60s most areas except for lower 70s along the coast due to the breezy onshore flow. Main updates were to trend POPs toward latest radar trends and follow some of the enhanced moisture fields from the guidance and latest HRRR during the day on Monday. Otherwise, no other significant changes planned at this time. && .NEAR TERM...(through Tonight)... High pressure ridging continues today and into tonight continuing onshore flow and low level moisture over the area. Scattered showers will continue to make their way inland from the coast mainly over northeast Florida this afternoon, shifting north into Southeast Georgia overnight. Today highs will be in the upper 70s to low 80s region wide. Overnight temperatures will be in the low 60s over southeast Georgia and mid to upper 60s over Northeast Florida staying slightly warmer along the coast. && .SHORT TERM...(Monday through Tuesday night)... Breezy onshore flow persists through Tuesday with a strong, dominant surface high and supporting blocking ridge aloft situated northeast of the region. Moisture will be lacking a bit Monday as another inverted coastal trough develops. The lack of moisture will challenge shower development over the coastal waters and lead to mainly dry conditions. By Tuesday, transport flow will start to veer southeasterly, sending a plume of rich tropical moisture into the region. That moisture intrusion will gradually grow instability Tuesday afternoon, mainly across north-central FL, where an isolated thunderstorm could develop. Temperatures will be boosted by the flow and will challenge daily record maximum temperature records (CLIMATE section below), especially Tuesday with highs pushing into the middle 80s! && .LONG TERM...(Wednesday through Saturday)... Stubborn upper ridge will begin to break down and flatten as a shortwave rides overtop of it Wednesday into Thursday. The rate that this occurs will dictate the main weather story this week - the potential tropical system that is currently brewing in the southwestern Caribbean. That system will be steered into the southeastern Gulf of Mexico Wednesday and slow down and may stall Wednesday night into Thursday as steering flow weakens. Though uncertainty exists in the direction of this system Thursday and Friday, the main threat for the local area will be the potential for heavy rainfall. Latest ensemble guidance indicates, the heaviest rainfall and potential for flooding will focus northwest of the area along a stalled frontal boundary. Temperatures will stay above normal this period as rain chances push above climo with the tropical airmass lifting across the region. && .AVIATION... (00Z TAFS) Issued at 650 PM EST Sun Nov 3 2024 Over the next few hours, low broken clouds expected to affect most of the TAF sites with IFR expected at times for CRG, VQQ, and SSI, and low-end MVFR cigs for SGJ, JAX, and VQQ. Appears that GNV and SGJ have better odds of VFR cigs. Isolated to scattered showers expected tonight but will most likely for the coastal areas north of SGJ. The IFR conditions from CRG to SSI may linger past midnight and may need to amend for SSI later tonight where IFR clouds could continue. However, based on HREF and HRRR the IFR cigs appear to shift further inland after 06z into the inland sections of southeast GA. Monday, another chance of isolated showers but looks few and far between to include a VCSH for all the TAFs. There may be an MVFR cig around Monday morning 11z- to 14z but overall probabilities appear low enough to indicate only FEW-SCT stratocu deck for now. Sfc winds will be relaxing from the northeast to about 5-10 kt tonight and then becoming more easterly about 10-14 kt and gusty on Monday. && .MARINE... Issued at 213 PM EST Sun Nov 3 2024 High pressure ridging continues over the area into the beginning of the week as a strong high pressure system over the Great Lakes slowly moves offshore of coastal New England Monday. This will help continue coastal toughing over adjacent waters producing daily coastal showers. A Small Craft Advisory has been issued for strong East-northeasterly winds and higher seas over the Southeast Georgia waters today and continues into early part of the week. High pressure moves further into the Atlantic by mid- week as a potential Tropical System develops in the Caribbean Sea and moves northward into the southern Gulf of Mexico. Rip Currents: High rip current risk for all area beaches through Tuesday. && && .PRELIMINARY POINT TEMPS/POPS... AMG 62 79 63 84 / 10 20 10 10 SSI 67 78 70 81 / 30 30 10 10 JAX 66 83 68 85 / 30 10 10 10 SGJ 70 81 71 83 / 30 10 10 20 GNV 65 84 66 86 / 20 10 10 10 OCF 65 84 67 86 / 0 20 10 20 && .JAX WATCHES/WARNINGS/ADVISORIES... FL...High Rip Current Risk until 4 AM EST Monday for FLZ124-125-133- 138. GA...High Rip Current Risk until 4 AM EST Monday for GAZ154-166. AM...Small Craft Advisory until 2 PM EST Wednesday for AMZ450-470-472- 474. Small Craft Advisory from 5 AM Monday to 2 PM EST Wednesday for AMZ452-454. && $$
Area Forecast Discussion
National Weather Service New Orleans LA
523 PM CST Sun Nov 3 2024 ...NEW AVIATION... .SHORT TERM... (This evening through Monday night) Issued at 306 PM CST Sun Nov 3 2024 This afternoon, recent radar/obs trends indicate some very shallow/light shower activity across coastal SE LA underneath a persistent onshore, moist return flow regime. Taking a step back and looking at the state of the troposphere using the 12Z KLIX RAOB and HRRR sounding trends illustrate a moistening low-levels from the LCL around 3kft AGL to the base of a subsidence inversion at around 8.5kft AGL, which given warm afternoon temperatures helping to develop a well-mixed PBL, has provided a slither of positive bouyancy in this aforementioned layer. SPC Mesoanalysis/sfc wind obs indicate subtle surface confluence extending in an axis from well offshore south of Mobile Bay, NW to Plaquemines Parish also influencing in the support for these shallow showers. NBM PPI is not picking up on this activity (perhaps, best being the HRRR initializing it somewhat) so did add in manually to 14 PoP for drizzle mention to 15 PoP for iso showers across mainly coastal areas into tonight. Just one of those moist return flow situations where a passing rogue shower/drizzle can be squeezed out at any time, but tried to pinpoint greater chances in the forecast. Otherwise, forecast hodographs indicate a slight increase in depth/curvature in the low-levels starting this afternoon, highlighting a steady uptick in WAA pattern building across the region. This gusty region in the vertical being at the top of the boundary layer will support downward flux transport of breezy winds this afternoon/evening, and regardless of decoupling, will keep winds "elevated" enough tonight to reduce surface fog production/maintenance. This gives scientific reasoning behind the NBM`s drop in low visibility probabilities, however may still see low stratus in locations like we typically see in this type of warm pattern. Also, did catch on going back on verification to notice we`ve been a tad too cool with overnight lows. With this warm/moist flow intensifying and remaining parked over the area, didn`t hesitate to hedge closer to the 75th percentile for overnight lows keeping them quite warm, likely breaking some record warm lows (BTR specifically has a record warm low of 69 Monday, set in 1959, 1973 and 1988 with a forecast low of 74. MSY record warm low of 71 on Monday, set in 1975 with a forecast low of 74). Just something to watch. Starting out the new work week tomorrow fairly similar to today. Warm again with highs flirting with records in some locations yet again. Breezy at times in the afternoon, and can`t rule out an isolated rogue shower or two (did manually introduce ~15% PoP in the afternoon for most areas) but generally speaking, primarily a dry day with partly to mostly cloudy skies. Did want to briefly touch on the coastal flooding situation. Guidance this afternoon started to highlight a bit more of a concern for impacts mainly during/around high tide cycles coming up. More particularly, the Monday night into early Tuesday morning tide cycle being the peak with Waveland`s current NAEFS-Based forecast touching ~4-4.2ft MLLW / 2.4-2.6ft MHHW in the 90th percentile. Went ahead an extended the advisory for coastal areas from originally ending 6AM Monday to now 6AM Tuesday, but did introduce a Coastal Flood Watch for south and east-facing shorelines from Hancock, south to SE LA coastal areas 00Z TUE - 12Z TUE to account for this impactful cycle potentially needing a warning. Will let subsequent shifts/updates take a closer look at the guidance to decide to upgrade to warning or revert to advisory, but wanted to get the messaging out for now all due to increase SE flow/fetch in the forecast. KLG && .LONG TERM... (Tuesday through Saturday night) Issued at 306 PM CST Sun Nov 3 2024 Now to spend some time in the long range... we`ll see how fast I get a headache by the end of it. Starting out with an overview, persistent, deep 588dm H5 ridging remains anchored over the SE Atlantic coastline, staying strong and not wanting to budge much. Meanwhile, a positive-tilt longwave trough axis over the central US, responsible for the active weather out that direction will quickly deamplify and weaken racing northeast around the periphery of the ridge. Surface reflection highlights a weakening surface low ejecting up across the Midwest into the Great Lakes region, with trailing cold front progressing slowly east across the MS valley region. The combination of the strong ridge in place and weakening upper-level support will slow the front to our north/west to a crawl, likely stopping before sliding through our area before turning back north as a warm front (or what would be left of it) into Wednesday. So locally, staying warm with the moist return flow parked in place, still a chance of an isolated shower or two but mainly dry. Then there`s the tropics. We`re already starting to see slow/steady development with a tropical wave in the south-central Caribbean. NHC has now brought this system up to a Potential Tropical Cyclone #18 as this system will likely continue to develop. Will go ahead and say, for the short-term, confidence is higher with ensemble spread honing in on the movement through the next 60-84 hours continuing to drift northeast, north, then northwest towards the Isle of Youth/NW tip of Cuba in a generally favorable environment. Briefly looking at intensify forecasts shows a pretty large swath of solutions, with the possibility of either slow /steady development, or quickly growing much stronger as what some of the dynamical hurricane models show. For now, NHC`s track/intensity reaching hurricane strength by the time it reaches the NW Caribbean impacting far western Cuba. But as the system continues northwest, could start to encounter a degree of southwesterly shear and even dry air meaning some weakening is possible as it gets more into the Gulf mid-week. Small additional tidbit about the wind shear/dry air: Don`t discount that. Looking at water vapor right now shows the intense depth of tropospheric dry air across the southern periphery of the ridge from the mid- atlantic, west to the GOMEX and will continue to pump west as the system punches through it to the northwest with time. If the wind shear can take more of a hold of it, tilts the system more to the east and allows the dry air to work into it, could really make a difference. This time of the year, with baroclinic systems diving much farther south hosts all sorts of challenges in and variables to monitor, It`s practically an atmospheric balance game. Ridge strength, position, system intensity, position, speed, degree/location of shear and dry air and how it`ll interact with the system all are in question this far out. Not going to pick/choose guidance, not going to side one way or the other but wanted to emphasize the NHC`s forecast seems very spot on given a collective understanding of all the variables mentioned, but could still change and bears close watching. I know a hurricane in the Gulf in early November was probably not on a lot of peoples bingo card for the 2024 Hurricane Season, but goes to show the need to stay vigilant, and ready/prepared at any point during hurricane season. As we get into around mid-week, more will become clearer so check back and we`ll do our job to pass along the latest information. KLG && .AVIATION... (00Z TAFS) Issued at 517 PM CST Sun Nov 3 2024 No low VIS/fog tonight as low level flow remains elevated. However, there will be some low stratus possible with brief reductions to MVFR or perhaps IFR, especially BTR, HDC, and MCB. Otherwise, VFR conditions can be anticipated. Southeast winds will increase again on Monday with some gusts up to 25 to 30kts not out of the question, especially coastal terminals. (Frye) && .MARINE... Issued at 306 PM CST Sun Nov 3 2024 Persistent onshore southeasterly flow will continue tonight into early/middle portions of this upcoming week. Winds on average around 15-20 knots can be expected, with occasional gusts to 25 for all Gulf waters and portions of the Sounds have led to Small Craft Advisories that remain in effect. Increasing/intensifying fetch across the Gulf will also lead to a response in waves/seas increasing tonight into Monday and Tuesday. However, gradient flow is expected to relax more around mid-week, with a temporary reduction in winds and waves/seas. Next focus will be on the potential for a tropical system in the southern and central Gulf late week. For now, confidence remains low on specifics to impacts to the local marine waters. For the latest information, visit www.nhc.noaa.gov. KLG && .PRELIMINARY POINT TEMPS/POPS... MCB 69 83 68 83 / 10 20 10 40 BTR 74 88 73 87 / 10 10 20 40 ASD 70 84 69 85 / 20 20 10 20 MSY 74 85 73 85 / 10 20 10 20 GPT 71 82 71 83 / 20 20 10 20 PQL 71 86 70 87 / 20 20 10 20 && .PRELIMINARY POINT TEMPS/POPS... MCB 69 83 68 83 / 10 20 10 40 BTR 74 88 73 87 / 10 10 20 40 ASD 70 84 69 85 / 20 20 10 20 MSY 74 85 73 85 / 10 20 10 20 GPT 71 82 71 83 / 20 20 10 20 PQL 71 86 70 87 / 20 20 10 20 && .LIX WATCHES/WARNINGS/ADVISORIES... LA...Coastal Flood Advisory until 6 AM CST Tuesday for LAZ058-060-077- 080-082-084-086>088. Coastal Flood Advisory until 6 PM CST Monday for LAZ066>070-076- 078. Coastal Flood Watch from Monday evening through late Monday night for LAZ066>070-076-078. GM...Small Craft Advisory from 9 PM this evening to 6 PM CST Monday for GMZ536-538-550-552-555-557-572-575-577. Small Craft Advisory until 6 PM CST Monday for GMZ570. MS...Coastal Flood Advisory until 6 AM CST Tuesday for MSZ087-088. Coastal Flood Advisory until 6 PM CST Monday for MSZ086. Coastal Flood Watch from Monday evening through late Monday night for MSZ086. GM...Small Craft Advisory from 9 PM this evening to 6 PM CST Monday for GMZ538-550-552-555-557-572-575-577. && $$ SHORT TERM...KLG LONG TERM....KLG AVIATION...RDF MARINE...KLG
Area Forecast Discussion...UPDATED
National Weather Service Memphis TN
536 PM CST Sun Nov 3 2024 ...New AVIATION... .SYNOPSIS... Issued at 330 PM CST Sun Nov 3 2024 Warm and windy conditions will persist tonight and Monday ahead of a cold front. A slow-moving cold front will bring showers and a few thunderstorms to the Mid-South Tuesday and Wednesday. Unsettled weather will continue through late week as the front remains over the region. && .DISCUSSION... (This evening through next Saturday) Issued at 330 PM CST Sun Nov 3 2024 It`s a warm and windy day across the Mid-South. We have seen several wind gusts over 35 mph as a 40 knot 925mb jet remains overhead. Temperatures are in the upper 70s to around 80 degrees across the entire area. The latest KNQA radar sweep reveals a large swath of showers moving south to north across portions of eastern Arkansas. Hi-res models failed to capture this activity this far east, but trends suggest that it will taper off by this evening as upper level heights build back in. Thereafter, mainly dry and windy conditions will persist over the next 24 hours. The large trough, currently over the Intermountain West, will deepen over the next 24 hours and a strong low level jet will move overhead. 925mb winds will strengthen to 50 knots over the Lower Mississippi Valley tomorrow. This will result in moderately windy conditions across at least the western half of the forecast area. The strongest winds appear to be over northeast Arkansas and the Missouri Bootheel, but could expand east of the Mississippi River. Current NBM guidance is underperforming wrt to winds, so opted to go with NBM 90 and a higher gust multiplication factor. Sustained winds of 20 mph will be prevalent across the majority of the area with 25 mph or greater mainly over northeast Arkansas and the Missouri Bootheel. A wind advisory is in effect from 9AM to 7PM tomorrow for the aforementioned area. A cold front will move into the region late Monday night and slowly traverse the area through Wednesday. The highest rainfall totals will occur mainly on Tuesday with 1 to 1.5 inches possible. The front is expected to stall across the region through late week, as the main trough dampens and lifts northeast of the region. Deep southwesterly flow will setup across the region on Thursday in response to another deepening trough over the Four Corners Region. The stalled front will back north of the region on Thursday. Chances for near-record high temperatures will occur on both Thursday and Friday. Newly introduced Potential Tropical Cyclone Eighteen, that is currently in the western Caribbean Sea, will move northeast through the Gulf of Mexico over the next week or so. This system`s track will need to be closely monitored, as it has the potential to interact with a mid-latitude cyclone in the Lower Mississippi Valley next weekend. Both Ensemble and Deterministic guidance suggest that tropical moisture will interact with a frontal boundary over the Mid-South next weekend. Significant rainfall could occur over portions of the Mid-South as PWATs climb above 2 inches. Stay tuned. AC3 && .AVIATION... (00Z TAFS) Issued at 537 PM CST Sun Nov 3 2024 Raw HRRR and GFS/LAMP guidance suggest current trend of limited gusts will persist through about 03Z. LLWS remains marginal across the Midsouth overnight, peaking at 09Z with about 20 degrees of veering through lowest 2kft. Isolated -SHRA will primarily affect JBR, but should present relatively limited impact. Primary aviation weather impact for Monday will remain gusty southerly surface winds, peaking 15Z-18Z with the deepening low level mixed layer. PWB && .MEG WATCHES/WARNINGS/ADVISORIES... AR...Wind Advisory from 9 AM to 7 PM CST Monday for ARZ009-018-026- 028. MO...Wind Advisory from 9 AM to 7 PM CST Monday for MOZ113-115. MS...None. TN...None. && $$ PUBLIC FORECAST...AC3 AVIATION...PWB
Area Forecast Discussion
National Weather Service Pocatello ID
724 PM MST Sun Nov 3 2024 .UPDATE... HRRR shows patchy fog and low stratus developing in the Magic Valley later tonight. This is an area where skies are mostly clear and likely to see fog/stratus. If it develops it will likely expand towards Shoshone, Craters and towards the Coldwater area. 13 && .PREV DISCUSSION... /issued 112 PM MST Sun Nov 3 2024/ SHORT TERM...Afternoon visible satellite imagery shows gradually clearing skies across the region as the weather system that brought clouds and snow to the area shifts to the east. The break in clouds and precip will be short-lived as our next system will come during the second half of the day Monday but for now, things are relatively quiet. We could still see an isolated snow shower this afternoon across the higher terrain of the central mountains or eastern highlands but even these will be hard to come by beyond sunset. Skies will clear decently overnight allowing for temps to drop into the teens 20s throughout the region, single digits around Island Park and Stanley. By mid to late afternoon tomorrow, clouds will begin to increase ahead of our next weather system as an upper level trough again digs into the area with some enhanced waves of vorticity moving through the base of the trough sparking another period of snow for the region. Snow will primarily be focused across the higher terrain, especially the eastern highlands and areas that perform well in NW upslope regimes. Overall totals have trended downward somewhat and look generally sub-advisory but some light accumulations can certainly be expected. Does look like the lower valleys won`t see much with this feature but some snow showers, maybe a light dusting, will be possible but shouldn`t be anything too problematic. As this feature moves in, winds will increase especially late Monday and into Tuesday AM so we could have some blowing/drifting issues in some of our usual higher elevation trouble spots but winds aren`t that strong so these concerns are likely more isolated. After this system, we should have some more sunshine and drier weather to contend with at least for a few days. More on that below. McKaughan LONG TERM...Tuesday through next Sunday. The upper trough and associated cold front will shift southward on Tuesday through Idaho before high pressure returns for the majority of the extended timeframe and keeps dry conditions in the forecast Wednesday through next Saturday. This system will be quick-moving with modest snow totals, which have trended slightly lower since the last forecast package. Snow accumulation through late Tuesday will be 2 to 7 inches above 6,000 feet with localized peaks seeing closer to 9 inches and a Trace to an inch below 6,000 feet. While many of our mountain passes further west are looking to only receive a couple inches of snow, Raynolds Pass and Targhee Pass will see closer to 4 inches with Emigration and Pine Creek Passes forecast to receive 5 to 6 inches. Our low elevations below 5,000 feet will see a rain/snow mix. Winds ahead of and along the front will be windy, with sustained winds generally 25 to 35 mph and gusts 35 to 50 mph. Considering the timing and widespread coverage of these winds, the potential for blowing/drifting snow and localized reductions in visibility will be elevated. All of Southeast Idaho will observe much colder temperatures during the period, with both high and low temperatures running 10 to 20 degrees below climatological norms at times. Overnight temperatures will take a big hit Tuesday night behind the front, with clear skies allowing overnight lows to drop into the teens and single digits CWA-wide. Temperatures will decrease overall through around mid-week before high pressure returns and helps to warm temperatures back into the 40s and within several degrees of "normal" across much of Southeast Idaho by Saturday. After that, ensembles feature another Pacific trough moving onshore late Saturday into Sunday. Cropp AVIATION...Skies continue to clear across much of the area and VFR should prevail at all terminals except KDIJ into the first half of the day tomorrow. KDIJ is still dealing with lingering clouds and light snow showers that can lead to some MVFR/IFR reductions. Will have to monitor the potential for some overnight stratus from KBYI up the Snake Plain to KPIH and KIDA but for now, the forecast doesn`t show this. Winds will be light for the next 24 hours as well but will pickup late Monday and into Tuesday AM as our next system moves through. McKaughan && .PIH WATCHES/WARNINGS/ADVISORIES... None. && $$
Area Forecast Discussion
National Weather Service Springfield MO
541 PM CST Sun Nov 3 2024 .KEY MESSAGES... - Multiple rounds of showers and thunderstorms will continue through Tuesday. Confidence is high in several inches of rain, with widespread totals of at least 2-5" by the end of the event, with localized amounts up to 6-9" confined to narrow corridors. The heaviest rainfall axis is currently located along and south of a Branson to Salem line. - There is a Slight (level 2 of 5) Excessive Rainfall Risk on through Monday. A Flood Watch is in effect for portions of SE KS and portions of far S MO from 6pm Sunday through 6am Tuesday due to multiple rounds of rainfall. - Sunday Night Severe Outlook: Slight severe risk (level 2 of 5) for Springfield and points southwest tonight as thunderstorms move out of Oklahoma and Arkansas. Damaging winds up to 60mph and a line embedded tornado are the main threats. - Monday Afternoon/Evening Severe Outlook: Enhanced (level 3 of 5) Risk for the far SW corner of Missouri and a Slight (level 2 of 5) Risk for most of the rest of the Missouri Ozarks. Damaging winds would be the primary threat with the line of storms, though there will also be the potential for a few embedded tornadoes. && .SHORT TERM /THROUGH MONDAY NIGHT/... Issued at 145 PM CST Sun Nov 3 2024 Current Conditions and Synoptic Pattern: A highly amplified shortwave trough was located across the Rockies with deep southwest flow aloft across the region. Low level moisture continues to stream into the area with the 12z KSGF sounding measuring 1.35in of PW which is near the max for early November. A low level front has lifted north of the area earlier this morning with low 60 dewpoints common across the area. This front then stretches west into low pressure across western Nebraska. A dryline was located across west Texas. A batch of showers and thunderstorms moved into the area this morning however it continues to move east, affecting areas along and east of Highway 65. Cloud cover was thick across the area which has kept temps down into the low 60s. This is keeping the instability to a minimum with the latest RAP showing less than 250j/kg of ML and MU CAPE. This afternoon and evening: Additional energy is moving into western Oklahoma and has already initiated showers and thunderstorms across Oklahoma in a more unstable environment (ML CAPE over 1000j/kg). This activity will likely begin to enter southwest Missouri during the 4-8pm timeframe. The lack of instability should keep these storms subsevere with just a few lightning strikes and moderate rainfall rates. Overnight: As we head into the late evening and overnight hours there are indications that instability could increase slightly as the low level jet intensifies again. The highest chances of seeing this instability increase will be to the southwest of Springfield (Joplin/Pineville). However the latest 12z HREF does not increase much instability overnight. This has implications on our severe and rainfall threats overnight. A corridor of severe storms looks to develop across central and eastern Oklahoma this evening and then push northeast into western Arkansas. These storms will attempt to then move northeast into southwest Missouri. 0-6km shear of 40-50kts is plenty for organized storms however the instability seems to be the limiting factor for a more widespread severe event. However we will be monitoring the instability levels, especially on our 00z sounding this evening. If storms can maintain severity into the area then damaging winds up to 60mph and a tornado will be the primary concerns. Highest severe chances are southwest of our area. The other concern for the overnight hours is the potential for training thunderstorms given the extremely high moisture content and continued low level jet feeding convection. Latest 12z guidance suggests that this corridor could set up just to the southeast of I-44. This does follow the southward qpf trend over the last 12-18 hours. Where this corridor sets up will experience rainfall rates of 1-2 inches per hour. The latest HREF (LPMM) guidance shows potential for 2-5 inches of rainfall in this corridor with the overnight round of rainfall with a 50-70% chance of 4 inches or more along and south of a Gainesville to Salem line. However since this is a convective rainfall event, any deviation north or south with the storms could have serious implications on these amounts. The current Flood Watch remains in effect and no changes planned for the area or time. Monday through Monday Night: The upper trough will continue pushing east during the day and while there will be morning rain, we do think that there will be some periods of dry time during the day. This will have big implications on instability. Surface low pressure will continue to develop across Oklahoma and move into southeast Kansas by the afternoon with the dryline along with it. Of concern is the latest HREF guidance indicating 1000j/kg of CAPE developing across the area during the afternoon and evening. This would occur if we could get some dry time/peaks of sunshine otherwise CAMS could be too aggressive with instability. By late afternoon and evening guidance breaks out scattered to numerous showers and storms along the front from eastern Kansas into eastern Oklahoma. Forecast soundings show strong wind fields aloft with 0-6km shear around 60kts and 0-3km shear of 50kts. Therefore instability will be critical to the severity of thunderstorms. If instability is high enough (ML CAPE 500-1000j/kg) then line segments will develop with damaging winds up to 60mph and QLCS tornadoes. We will need to monitor this threat closely with the enhanced risk just southwest of Springfield. This would likely be during the mid evening and overnight hours as the line sweeps through the area. Additional rainfall with this round looks to be in the 1-2 inch range. When combined with previous rainfall, LPMM data suggests a widespread 2-5 inch storm total with a corridor of 6-9 inches of rainfall. While many areas are in drought, drought conditions are not as severe in the eastern CWA. This is also the most flood prone area of our CWA therefore we will need to closely monitor river and creek levels. Latest HEFS guidance indicates potential for several creeks and rivers to rise into Action and or Minor flood stage however this will be highly dependent on that heavy rainfall axis. A few river Flood Watches have been issued already. && .LONG TERM /TUESDAY THROUGH SUNDAY/... Issued at 145 PM CST Sun Nov 3 2024 The trough will be pushing through the area during the day therefore expecting a decrease in clouds/rain during the day. Ensembles suggest that the southwest flow pattern will not go away with a quick return by Wednesday as another disturbance moves into the Rockies. Ensembles begin to diverge by Thursday as the guidance is split on the trough closing off and slowing down or ejecting faster east. Currently the majority of guidance is much slower therefore rain chances are currently low for Wednesday and Thursday (10-30%) and then increasing Friday into Saturday (30-50%). The speed of this trough will greatly affect precip chances late next week. Temps look to remain around average (highs in the 60s). && .AVIATION /00Z TAFS THROUGH 00Z TUESDAY/... Issued at 536 PM CST Sun Nov 3 2024 Rounds of showers and thunderstorms will continue to push through the area tonight into Monday night. Storms may be strong tonight and could be severe on Monday afternoon into Monday night. Gusty winds and strong wind fields aloft will continue as well. && .CLIMATE... Issued at 145 PM CDT Sun Nov 3 2024 Record High Minimum Temperatures: November 3: KSGF: 63/1994 November 4: KSGF: 59/1994 Record Precipitation: November 3: KJLN: 2.05/1974 November 4: KSGF: 2.32/1994 KJLN: 2.16/1994 KVIH: 1.91/1994 KUNO: 2.20/1994 && .SGF WATCHES/WARNINGS/ADVISORIES... KS...Flood Watch through late Monday night for KSZ073-097-101. MO...Flood Watch through late Monday night for MOZ066-077-078-082- 083-088>098-101>106. && $$ SHORT TERM...Burchfield LONG TERM...Burchfield AVIATION...Titus CLIMATE...Burchfield