####018004470#### FXUS64 KMEG 040225 AFDMEG Area Forecast Discussion National Weather Service Memphis TN 925 PM CDT Fri May 3 2024 ...New UPDATE... .UPDATE... Issued at 915 PM CDT Fri May 3 2024 Main concern overnight is fog development. Clouds are moving off to the NE and some clearing has already occurred across western sections of the Mid-South. Most of the area has seen at least some rain during the last 24 hours and little if any drying occurred today. Dewpoint depressions have already fallen to 1 degree or less over much of the Mid-South. Low temps will crash through the crossover temp as well. The latest HRRR model runs have been indicating at least areas of dense fog as well. Given all this evidence have decided to go ahead and issue a Dense Fog Advisory for the entire Mid-South from 1 am to 9 am Saturday. Also, cut pops for the remainder of the night. && .SYNOPSIS... Issued at 330 PM CDT Fri May 3 2024 Active weather will persist across the Mid-South over the next 7 days or so. Showers and thunderstorms will be possible each day as upper level disturbances move through. There is the potential for organized weather towards the middle of next week as a low pressure system moves into the region. Temperatures will likely remain near normal due to clouds and storms each day. Expect highs around in the lower 80s and lows in the 60s. && .DISCUSSION... (This evening through next Thursday) Issued at 330 PM CDT Fri May 3 2024 A mostly dry day across the Mid-South at this hour. Two decaying MCSs moved into the area this afternoon, but didn't produce much convective activity as previous model guidance suggested. The most active weather is currently near the Alabama and Mississippi stateline, where a cluster of slow-moving strong storms have congealed. Hi-res models continue to struggle with shower and thunderstorm coverage across the region. The latest thinking is that this activity will continue to slowly lift northeast through sundown and taper off after sundown with the loss of daytime heating. Weak southwest flow aloft will persist through early next week. This will allow several weak perturbations to translate through the region. This weather pattern will continue to pose a challenge for nearly all model guidance, as steering flow will be weak and not well resolved. Using a more probabilistic approach is likely the best scenario here, however the 12Z HREF is not showing much in the way of precipitation for Saturday. Nonetheless, went with the NBM, which keeps 40 to 60 PoPs over the Mid-South tomorrow afternoon. Convective coverage looks a bit better on Sunday as a weak cold front and shortwave move into the region. Organized weather appears more likely by the middle of next week, as a large upper low ejects through the Central Plains. Subtle height falls will occur Tuesday night into Wednesday, where a Day 5 Slight Risk has been introduced north of I-40. A better chance of strong to severe storms appears to be next Wednesday into Thursday, where a surface low will track to our northwest. Still a bit early to sort out specific details, as synoptic model guidance still has timing and feature differences. A cold front looks to move through by late week and bring cooler and drier air to the region for next weekend. AC3 && .AVIATION... (00Z TAFS) Issued at 637 PM CDT Fri May 3 2024 Occasional MVFR CIGS will linger across the airspace this evening. Later tonight, CIGS will eventually lower to IFR with the potential for reduced VIS to MVFR to IFR at various terminals. There is some potential that VIS will lower to LIFR conditions per latest guidance, but confidence in this scenario is low for now. Eventual improvement to VFR is expected across the airspace by late tomorrow morning or afternoon. && .MEG WATCHES/WARNINGS/ADVISORIES... AR...Dense Fog Advisory from 1 AM to 9 AM CDT Saturday for ARZ009-018- 026>028-035-036-048-049-058. MO...Dense Fog Advisory from 1 AM to 9 AM CDT Saturday for MOZ113-115. MS...Dense Fog Advisory from 1 AM to 9 AM CDT Saturday for MSZ001>017- 020>024. TN...Dense Fog Advisory from 1 AM to 9 AM CDT Saturday for TNZ001>004- 019>022-048>055-088>092. && $$ PUBLIC FORECAST...SJM AVIATION...JPR ####018008071#### FXUS61 KBTV 040229 AFDBTV Area Forecast Discussion National Weather Service Burlington VT 1029 PM EDT Fri May 3 2024 .SYNOPSIS... Dry and seasonably warm weather will continue across the region to start the weekend, with the exception of a few possible showers across northern New York on Saturday before widespread precipitation returns for Sunday. A period of warmer and sunnier conditions are expected for the start of the week, with more unsettled weather returning by the middle of next week. && .NEAR TERM /THROUGH SATURDAY NIGHT/... As of 1024 PM EDT Friday...Updated to increase pops to low likely acrs the SLV as radar and sfc obs show a band of light rain approaching the area. Given the high cloud heights and relatively dry low levels, expecting precip will be very light with only a few hundredths of an inch. Otherwise, south winds here locally have kept temps in the l/m 60s this evening, so have bumped hourly temps up by 2 to 4 degrees. Rest of fcst in good shape, with lows mid 40s to mid 50s. Previous discussion below: Surface high pressure and upper level ridging across the region haver made for a pleasant Friday afternoon, with dry conditions and seasonably warm temperatures. As we head into the evening, the upper level ridge axis will continue to shift eastward,although dry conditions will persist. There will be increasing high clouds across the region overnight associated with a frontal boundary to our west. Unlike the last few nights, increased clouds and winds will inhibit any fog development across the region. A light rain shower or two may be possible across northern New York early Saturday morning as the frontal boundary moves closer, but any measurable precipitation would be minimal. Overnight low temperatures will be mild, in the 40s to low 50s. Saturday will be another pleasant day as we remain under the influence of high pressure, with mostly dry weather. Temperatures will warm into the 60s to near 70 in some of the broad valley locations, with high clouds remaining overhead. Dry weather will continue through most of Saturday night, with the latest guidance continuing to trend on the drier side for Saturday night with a strong ridge axis in place. Another mild night is expected, with temperatures in the 40s to low 50s ahead of approaching widespread precipitation on Sunday. && .SHORT TERM /SUNDAY THROUGH SUNDAY NIGHT/... As of 303 PM EDT Friday...PWATs rise to around 1.5 standard deviations above normal on Sunday as moisture with Gulf of Mexico origin looks to overspread the region. Upper level pattern shows a stout omega block shifting east of our area into Maine, increasing shower chances and coverage on Sunday. However, organized convection is not expected as the main jet energy associated with the shortwave trough moving eastward from the Great Lakes is diverted into Quebec. As a result, the main trough axis does not approach North Country until sometime next Tuesday. This will be discussed in the long term section of the forecast discussion. Indeed, forecast soundings show a lack of surface-based instability, so showers with brief locally heavy downpours look to be the main risk. While there could be embedded thunder due to elevated instability, no organized thunderstorms are anticipated. PoPs do increase to the likely category with scattered to perhaps numerous showers on Sunday. While there would likely be widespread wetting rainfall, QPF amounts are quite manageable in the 0.1 to 0.3 inch range with locally higher amounts. Indeed, the MMEFS shows none of our area rivers going into action stage. Sunday will be quite a bit cooler than Saturday, with highs only in the 50s with low 60s possible if there are breaks in the rain or clouds. In addition, a 40-50 kt 925mb southerly low level jet overspreads the region on Sunday. NAEFS situational awareness ensemble table shows the v vector wind rising to almost 2.5 standard deviations above normal, so it will be breezy if not blustery. A mitigating factor is that the waters of Lake Champlain is still quite cold with water temperatures still in the low to mid 40s, which is almost isothermal to the forecast 925mb temperatures in the +5 to +8C range. That could reduce the mixing potential in the boundary layer. So have mostly kept wind gusts in the 30 to 35 mph range across the Champlain Valley despite the southerly wind component being anomalously strong. Overall, no overall hazardous weather to speak of but Sunday does look to be a less than ideal day for outdoor activities. Heading into Sunday night, showers taper off and the boundary layer looks well mixed enough to preclude widespread fog development. Temperatures stay quite mild in the mid 40s to low 50s. && .LONG TERM /MONDAY THROUGH FRIDAY/... As of 303 PM EDT Friday...The overall weather pattern heading into the first full week of May can be described as unsettled with no real significant warm up or impactful weather. Unsurprisingly, the CPC 8-14 day temperature outlook favors near normal temperatures and leans towards above normal rainfall. For reference, typical highs for North Country in early May are in the low to mid 60s, while average overnight lows are in the mid 30s to low 40s. The upper level pattern features a positively tilted omega block sandwiched between an anomalously deep trough across the Rockies/northern Great Plains and another trough over eastern Quebec/Newfoundland. H5 height anomalies favor a period of widespread showers and thunderstorms in the Tuesday/Wednesday time frame, as positive H5 height anomalies give way to near normal values. Depending on the timing of the associated surface cold front, ingredients may exist for a few stronger storms. Taking a first look at ensemble guidance probabilities, it does look like the better chance for organized convection is across our southwestern zones, with more garden variety thunderstorms towards Vermont and the Champlain Valley. This makes sense from a synoptic perspective as the aforementioned positively tilted omega block may not be that easy to dislodge. As a result, our region only gets a piece of weak shortwave energy that peels off from the base of the northern Great Plains upper low and deamplifies as it tracks towards southern Ontario/Quebec. In simple terms, our region gets a glancing blow in terms of dynamical forcing and as a result, the odds for any stronger convective storms greatly diminish. While we are still 4 days away, model trends are favoring an unsettled but benign pattern for North Country in the upcoming week. && .AVIATION /03Z SATURDAY THROUGH WEDNESDAY/... Through 00Z Sunday...VFR conditions will prevail through the forecast period, with the possible exception of brief MVFR conditions if scattered showers are sufficiently heavy at MSS and SLK. The timeframe for precipitation is mainly in the 05Z to 11Z period for MSS and 07Z to 12Z period for SLK, with showers expected to peter out as they move farther east. Terrain driven flow at the start of the period, mainly 3 to 7 knots, will trend southerly after 06Z, and then southeasterly after 18Z. Ceilings will tend to lower with time but remain at VFR levels through the period. Outlook... Saturday Night: VFR. Chance SHRA. Sunday: Mainly MVFR, with areas VFR possible. Definite SHRA. Sunday Night: Mainly MVFR, with areas IFR possible. Chance SHRA. Monday: Mainly VFR, with local IFR possible. Slight chance SHRA. Monday Night: VFR. NO SIG WX. Tuesday: VFR. NO SIG WX. Tuesday Night: VFR. Slight chance SHRA. Wednesday: VFR. Likely SHRA. && .BTV WATCHES/WARNINGS/ADVISORIES... VT...None. NY...None. && $$ SYNOPSIS...Kremer NEAR TERM...Kremer/Taber SHORT TERM...Chai LONG TERM...Chai AVIATION...Kremer/Kutikoff