textproduct: Burlington

WHAT HAS CHANGED

As of 258 AM EDT Wednesday...

No significant changes to the current forecast.

KEY MESSAGES

As of 258 AM EDT Wednesday...

1. Quiet weather today followed by showers and thunderstorms possible both Thursday and Friday.

2. Following a drier weekend, shower chances return into early next week, with slightly above normal temperature.

DISCUSSION

As of 258 AM EDT Wednesday...

KEY MESSAGE 1: Surface high pressure cresting overhead this morning will provide the region with a seasonable and dry day with partly sunny skies. Clouds will increase tonight ahead of next approaching system. A surface low pressure system will track from the Great Lakes area northeastward into Ontario and then Quebec. Series of frontal passages on Thursday into Thursday night will bring chances for showers and thunderstorms to our area. SPC has placed our region in Marginal risk for severe thunderstorms on Thursday. Moderate instability is expected ahead of a cold frontal passage as some higher dewpoints advect into our area on south southwesterly flow. Some modest shear may help some storms to become better organized with some strong winds and small hail possible. Areas further south of our forecast area will have better chances for severe storms. Additional showers are expected Friday as upper level trough trails behind departing surface fronts and crosses our area. Severe weather is not expected, though embedded thunderstorms will be possible.

KEY MESSAGE 2: Following a mainly dry weekend, there still looks to be some signs of subtle cyclonic flow as an upper low lifts north and east, which may spur some isolated shower activity in eastern Ontario and southern Quebec late Sunday. Some of which will bring some increase cloud cover and an isolated shower to the St. Lawrence Valley and areas near the International Border. Our flow pattern will gradually become more zonal towards late Sunday into Monday, favoring more hit or miss showers in the aforementioned areas. Temperatures will begin to increase above seasonable norms by 3-5 degrees, Sunday into Monday as a thermal ridge moves through the region. Highs Sunday into early next week will be in the upper 70s for the higher terrain, and low 80s in the wider valleys, which is supported by 850mb temperatures of 16-19C. Humidity will also be on the incline, peaking Monday in the low to mid 60s. The increase in humidity will be a result of a trough swinging through the area to start next week. Models are beginning to pick up on a weak shortwave that will ride through the thermal ridge Monday into Tuesday. Shower chances will increase by early Monday through Tuesday across the region. While ingredients will be marginal Monday, some thunder chances will be possible Monday afternoon driven by a weak frontal boundary passage. Thunder chances will also be possible Tuesday, but will be conditional on the frontal passage on Monday. A slower front Monday would help spur thunder chances, and perhaps some stronger storms Tuesday as storm chances would be associated with better instability and shear profiles. A faster front Monday would lower thunder chances Tuesday. While the pattern is relatively unsettled early next week, precipitation probabilities are generally low, with only a 20-40% chance for 0.5" highlighted in the northern portions of our area Monday into Tuesday in the GFS ensembles and AI suite.

AVIATION /12Z WEDNESDAY THROUGH SUNDAY/

Through 12Z Thursday...Fog and low stratus resulting in IFR vsbys and cigs below 500ft agl at SLK/MPV/RUT is expected to improve towards VFR between 12-13Z. Elsewhere low stratus to 3000-4000ft agl will become more scattered this morning lifting to around 5000ft agl by this afternoon. All sites should see VFR conditions beyond 14Z through the daylight hours. Winds will generally be light and variable 10 knots or less. A lake breeze at PBG/BTV will lead to southeasterly and southwesterly winds, respectively, between 15 and 22Z. By tonight, winds will begin to shift to prevailing southeasterlies and increase to prevailing 5-10 knots. There is a chance for fog tonight across eastern Vermont, with some clearing possible, though with winds above calm, there is low confidence at any site.

Outlook...

Thursday: VFR. Likely SHRA, Chance TSRA. Thursday Night: MVFR/IFR conditions possible. Chance SHRA, Slight chance TSRA. Friday: Mainly VFR, with local IFR possible. Chance SHRA, Slight chance TSRA. Friday Night: VFR. NO SIG WX. Saturday: VFR. NO SIG WX. Saturday Night: VFR. NO SIG WX. Sunday: VFR. NO SIG WX.

BTV WATCHES/WARNINGS/ADVISORIES

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