textproduct: Burlington

WHAT HAS CHANGED

As of 222 AM EDT Saturday...

Wednesday and Thursday have trended a bit hotter.

KEY MESSAGES

As of 222 AM EDT Saturday...

1. Aside from a couple of terrain driven thunderstorms this afternoon and rounds of nocturnal valley fog, no hazardous weather is expected over the next few days as temperatures trend warmer.

2. Hot and humid weather expected for mid to late week next week, with multiple rounds of showers/thunderstorms possible right through the holiday weekend.

DISCUSSION

As of 222 AM EDT Saturday...

KEY MESSAGE 1: Isolated cellular showers and a thunderstorm or two are expected to develop today; with lack of any other trigger, these will be driven by the terrain. CAMs suggest higher probability of thunderstorms across the Adirondacks than near/east of the Green Mountains, where there will be greater instability. Forecast soundings continue to show mainly 400 to 800 J/kg of surface-based CAPE and dry air in the 700-500 millibar layer this afternoon such that coverage and severity of thunderstorms will be quite low. Additionally while there will be plenty of deep layer shear given winds aloft, that aforementioned dry air will limit cloud growth such that it will be a challenge to tap into this shear or even produce lightning. Additionally, while any terrain-driven thunderstorm is capable of heavy rain, it appears they should propagate east or southeastward with time and only when they are shallower/weaker will storm motion be more erratic. Overall, this scenario bodes well to minimize any hydro concerns following recent wet weather. On Sunday and Monday, as the broad trough in place shifts further east, we trend drier such that diurnally driven CAPE may be insufficient to produce a repeat of any terrain-driven showers.

Radiation fog will almost certainly develop again tonight and Sunday night as high pressure further builds in with plenty of soil moisture and evaporation to feed its development overnight in the vicinity of rivers and lakes. We have bumped low temperatures downward a bit for the next couple of nights consistent with the expected mostly clear skies and fog development. As we move further away from fresh rainfall, expect primarily the typical deeper valley spots and other fog-prone areas will see patchy fog for the Monday and Tuesday morning commutes as compared to over the weekend. Temperatures may need to trend a little lower on these nights as well, although it is more uncertain, as crossover temperatures may be more difficult to reach with a warming/drying trend. Overall, through Tuesday morning each nighttime period looks comfortable for sleeping.

KEY MESSAGE 2: Summery conditions expected from mid week next week onward into the holiday weekend as high pressure builds eastward from the Ohio River Valley. The overall trend will be toward hot and humid weather as this high moves in; however, we also look to be active as models indicate the potential for ridge runner-type systems to ride up over the top of the ridge and across our region. Daytime temperatures will rise well into the mid 80s to mid 90s both Wednesday and Thursday. Dewpoints will be in the 60s and 70s, so quite uncomfortable, and serving to keep nighttime conditions mild and muggy. We'll get a bit of a reprieve as we head into the weekend, but it will still be hot and humid with highs in the 80s to near 90F. As mentioned above, periods of showers/thunderstorms are expected, especially in the afternoons as the heat and humidity will provide ample CAPE for storm development. Any precipitation could keep daytime highs a little lower than currently indicated, but regardless, it will be dangerously hot and humid, especially Wednesday through Thursday, when heat index values could approach 100F. Anyone with outdoor plans next week should stay aware of future forecasts and include both hot weather and thunderstorm safety steps in your plans.

AVIATION /12Z SATURDAY THROUGH WEDNESDAY/

Through 12Z Sunday...Other than local IFR in patchy fog early this morning, expect VFR conditions to prevail at all terminals through the daylight hours and the first part of tonight. Isolated to scattered showers/thunderstorms are expected to develop over the higher terrain this afternoon. Although areal coverage is not enough to warrant mention in the TAFs at this time, KSLK will have the best chances of seeing a shower/thunderstorm this afternoon. MVFR/IFR possible in any thunderstorms. Otherwise, SCT- BKN ceilings AOA 3500 ft today, giving way to another round of patchy valley fog tonight. Fog development most likely at KSLK/KMPV/KMSS, and perhaps KEFK/KRUT. IFR/LIFR likey in any fog, especially after 08z Sun. Light winds 6 kt or less through the entire TAF period.

Outlook...

Sunday: VFR. Patchy BR. Sunday Night: VFR. NO SIG WX. Monday: VFR. NO SIG WX. Monday Night: VFR. NO SIG WX. Tuesday: VFR. Chance SHRA, Chance TSRA. Tuesday Night: Mainly VFR, with local MVFR possible. Chance SHRA, Chance TSRA. Wednesday: Mainly VFR, with areas MVFR possible. Slight chance SHRA, Slight chance TSRA.

BTV WATCHES/WARNINGS/ADVISORIES

VT...None. NY...None.