textproduct: Burlington

WHAT HAS CHANGED

As of 313 PM EDT Friday...

Severe thunderstorm watch #397 has been cancelled as showers and thunderstorms have moved out of southern Vermont.

KEY MESSAGES

As of 313 PM EDT Friday...

1. Scattered showers and thunderstorms will exit our forecast area by 9 PM this evening with patchy fog developing overnight.

2. Heat and humidity will gradually build early next week. A round of showers and thunderstorms may occur late Tuesday into Wednesday, followed by additional chances of thunderstorms later in the week.

DISCUSSION

As of 313 PM EDT Friday...

KEY MESSAGE 1: GOES-19 mid lvl water vapor imagery shows potent s/w energy crossing northern NY/VT this aftn, while left front quad of 100 knot jet is angling toward southern VT and helping to enhanced deep ulvl divergence over Rutland/Windsor Counties. However, abundant cloud cover has kept temps mostly in the mid 60s to lower 70s today with dwpts upper 50s to lower 60s, creating sfc based CAPE values in the 500-1200 J/kg. Some breaks are evident in the latest GOES-19 satellite imagery over central/southern VT, ahead of broken line of developing convection over northern NY. The 0-6km effective shear is 35 to 45 knots, mostly driven off the strengthening 3-6km wind fields acrs central/southern VT. Given the above scenario, thinking dynamically driven showers and thunderstorms are likely with some stronger storms capable of localized wind gusts up to 60 mph, 1 inch hail and frequent cloud to ground lightning. Highest probability of stronger convection will be along and south of a SLK to MPV line through 7 PM this evening, and by 9 PM activity should be exiting our fa.

As strong subsidence builds acrs our cwa tonight per latest water vapor trends areas of clearing should develop with a combination of low level stratus and fog likely, especially given recent rainfall and saturated soils. Difficult challenge is areal coverage and what areas see stratus vs fog, but general idea of patchy dense fog looks good. Lows mostly in the 50s to near 60F.

On Sat widely scattered trrn driven showers and embedded storms are expected over the northern Dacks and parts of the central/northern Greens. Soundings indicate a small sliver of instability with CAPE values btwn 400-800 J/kg, but column is very dry btwn 800-500mb, which wl limit areal coverage of convection. The idea of garden variety activity is expected, given the lack of moisture/instability and shear on Sat. For Sunday 1016mb high pres noses into our cwa with drier air and less instability/moisture, which should result in mostly dry conditions. Still cannot completely rule out an isolated shower or two over the northern mtns, but probability and coverage wl be limited. Highs warm into the upper 70s to mid 80s with comfortable humidity values.

KEY MESSAGE 2: Summertime heat and humidity is expected to build for the beginning of next week, with high pressure centered over the Ohio Valley slowly nudging into the region. High temperatures look to climb into the upper 80s into the 90s throughout the week, with the warmest conditions expected towards the end of upcoming week. There is still some uncertainty as to the exact extent of the heat earlier in the week as confidence is increasing in the potential for a system along the periphery of the ridge Tuesday into Wednesday bringing increased chances for showers and thunderstorms. The air mass will be favorable in regards to heavy rain potential with PWAT surging well over 2 inches, but trends will still need to be monitored as we head into next week. Showers and cloud cover could impact how warm temperatures are able to climb. Thursday looks to have greater heat impacts given increased humidity, although there is still some uncertainty in the exact extent of the heat. With the warmth expected ahead, it is good to remember to stay hydrate and take frequent breaks if working outdoors. As we head throughout the week, the increased humidity will allow for additional chances for showers and thunderstorms.

AVIATION /00Z SATURDAY THROUGH WEDNESDAY/

Through 00Z Sunday...VFR conditions have returned in the wake of this afternoon's showers and thunderstorms. A few showers remain with best chances at SLK through 03Z and about a 10% chance for MSS/PBG/BTV/EFK. As the sun sets, chances will decrease further with skies beginning to clear in earnest. IFR conditions due to fog will be possible at most terminals overnight, but MPV/SLK/EFK are nearly certain. Some CIGs may linger in the morning through 14Z for some terminals, but otherwise lift and scatter. Wind flow will predominantly become northwesterly Saturday, except at PBG where some Lake breeze will drive an easterly surface flow.

Outlook...

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

BTV WATCHES/WARNINGS/ADVISORIES

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