textproduct: Burlington

WHAT HAS CHANGED

As of 359 PM EDT Saturday...

No significant changes.

KEY MESSAGES

As of 359 PM EDT Saturday...

1. A few showers tonight but mainly dry through Tuesday.

2. Brief high pressure will give way to cyclonic flow and periods of showery weather through Friday.

DISCUSSION

As of 359 PM EDT Saturday...

KEY MESSAGE 1: An upper low remains centered just to the east heading into Monday, keeping the region in a seasonably cool airmass. A few showers will continue to move through tonight, with a bit more widespread coverage over Vermont as a shortwave pivots through. After the shortwave exits, dry conditions will prevail through Monday. Skies will clear and it should be a great early fall stretch. Radiational cooling will be efficient Sunday night, with lows generally falling into the 40s and upper 30s. The current forecast low at SLK is 37, but it could easily fall a few more degrees if confidence increases in light winds. Warm air advection will begin for Monday and Tuesday, but it will be unsuccessful in causing a significant airmass change, with the humidity staying low and temperatures remaining around seasonable. A few showers are possible in northern areas Monday night and early Tuesday morning as a dying cold front passes into the region.

KEY MESSAGE 2: A broad upper high will be positioned to our south during the middle of next week. Between a departing trough and another one moving towards James Bay, there will be a 500mb ridge axis that extends well north into Quebec Province. Cool air will remain locked in eastern Vermont Tuesday night, but clouds and warm advection will begin impinging across northern New York. So eastern Vermont will tumble into the mid 40s, along with cool hollows of the Adirondacks, while most the rest of the region will stay in the 50s, and perhaps a few spot 60s in the St. Lawrence Valley as we open up Wednesday. Much of Wednesday will be dry, but cloudy. Winds at 850mb will be speedy at 50-55 knots, but it appears we'll have a modest inversion below that layer. Nevertheless, the pressure gradient from departing surface high pressure and a sub-990mb low to our north will promote gusty winds (at least 25-35mph) across the region by Wednesday afternoon. This will likely bring some 70s into the region, although some raw guidance suggests temperatures may be towards more the upper 60s to lower 70s range. Mid to late afternoon, a leading surge of warm air will overrun departing cool, stable air and produce some rain. Synoptic guidance is likely broad- brushing rain given the strong mid-level flow that will likely produce strong terrain shadowing downwind mountain areas. There's also plenty of dry air that must be saturated in the lower-levels. As we get into the range of mesoscale guidance, this will probably look less like a wash out. The occluded front and axis of a sharp upper trough will progress east late Wednesday evening into Wednesday night, and will be capable of additional showers and perhaps a thunderstorm or two.

Following this, we'll spend Thursday and Friday in cyclonic flow as the sub 990mb low continue east. Lingering, intermittent shower activity, especially in northwest facing slopes, will be possible. Friday's chances are somewhat more uncertain depending on how quickly dry air filters into Vermont and northern New York. It will be a notable surge of cool air behind this area of low pressure likely preventing day time highs from reaching the 70s for much of the area next Friday. Broad high pressure will establish itself across the weekend, signaling that the next weekend should be very nice.

AVIATION /00Z SUNDAY THROUGH THURSDAY/

Through 00Z Monday...Current radar shows a band of light rain showers approaching the International Border area as cyclonic northerly flow prevails across our region. These showers combined with northerly flow will help to lower cigs toward MVFR with intervals of MVFR vis in the heavier showers between 01z and 06z tonight. A mix of VFR/MVFR is anticipated most of the night with some intervals of IFR cigs/vis possible at SLK/MPV/EFK and BTV toward sunrise. However, feel probability of fog and LIFR/VLIFR at any given site is <30%, given the extensive cloud cover expected. Conditions improve to mostly VFR by 15z with some lingering MVFR cigs at MPV/SLK, along with north winds 5 to 10 knots and localized gusts 12 to 18 knots.

Outlook...

Sunday Night: VFR. NO SIG WX. Labor Day: VFR. NO SIG WX. Monday Night: VFR. Slight chance SHRA. Tuesday: VFR. NO SIG WX. Tuesday Night: VFR. NO SIG WX. Wednesday: Mainly VFR, with local MVFR possible. Likely SHRA, Slight chance TSRA. Wednesday Night: Mainly MVFR, with areas VFR possible. Definite SHRA, Slight chance TSRA. Thursday: Mainly VFR, with areas MVFR possible. Chance SHRA.

BTV WATCHES/WARNINGS/ADVISORIES

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