Norfolk, CT Weather

What has changed

In collaboration with NYS DEC and surrounding WFO's, issued Special Weather Statement (SPS) for elevated risk of fire spread on Friday for areas within and adjacent to the Hudson River Valley. Additional SPS's will also be issued for western MA/NW CT per coordination with WFO BOX and New England DEC/DEP's. Otherwise, continued trend of lowering afternoon dewpoints Friday through Sunday, and increased winds/wind gusts for Friday.

Key messages

1) Elevated risk for fire spread Friday for areas within and immediately adjacent to the Hudson River Valley, western MA and NW CT due to dry fuels combined with gusty winds and low RH.

2) Dry weather expected for this weekend through early next week, with next chance for widespread rainfall not until Thursday or Friday.

Discussion

KEY MESSAGE 1:

Cold front will cross the region from NW to SE Friday morning, preceded and accompanied by some rain showers across the SW Adirondacks before weakening. Isolated showers/sprinkles may extend farther south and east into the Capital Region, however will remain much more limited in coverage. In the wake of the cold frontal passage, gusty northwest winds are expected to develop with gusts reaching 25-35 mph late Friday morning into the afternoon hours. RH values will drop to 35-45 percent within lower elevations of the Hudson Valley and NW CT, and 45-55 percent within slightly higher elevations of the Helderbergs, eastern Catskills, Taconics, Berkshires and Litchfield Hills. In collaboration with NYS/New England DEC's/DEP's and surrounding WFO's, given the drying fuels across these areas with little or no rainfall over the last 7+ days, a Special Weather Statement has been issued for 11 AM-6 PM Friday for elevated risk of fire spread.

KEY MESSAGE 2:

Dry weather is expected this weekend through the middle of next week, outside the very low chance of showers with a passing frontal system Tuesday-Wednesday. Temperatures should initially be near normal this weekend, trending above normal next week. A stronger frontal system and approaching deep upper level trough from the west may bring widespread rainfall for next Thursday or Friday.

Aviation

Through 18z Friday: VFR conditions largely prevail across the region this afternoon, though an isolated patch of low stratus has forced MVFR conditions at POU. Per latest visible satellite images, these clouds are breaking up and should dissipate within the hour.

VFR conditions will prevail everywhere through the afternoon into this evening before clouds begin to increase ahead of an incoming cold front. Still, cloud bases will remain well within VFR thresholds through the vast majority of the night, slowly lowering from 10-25 kft to 3.5-8 kft after 06z as low-level moisture increases. The only terminals with a notable probability of precipitation are GFL and PSF due to adjacency to the primary moisture source (eastern Great Lakes) and orographic enhancement respectively. However, a low- to mid-level dry layer will likely significantly limit the magnitude of rainfall such that visibilities will not be impacted. Ceilings, too, look to remain within VFR thresholds as a result. Therefore, PROB30s for light showers with ceilings around 4-8 kft were implemented at GFL between 04-07z and 07-09z at PSF to account for this element of the forecast.

A persistent increase in low-level moisture could ultimately force some MVFR ceilings behind the front, particularly for ALB and PSF. However, since the passage of the front at these two terminals is progged to occur right before sunrise, these MVFR conditions should not be long lasting as deep mixing ensues right after daybreak. This mixing should ultimately scour out most of the cloud coverage, leading to mere FEW to SCT groups for the remainder of the 18z cycle.

Winds will remain breezy out of the south to southwest this afternoon before decreasing into this evening. Sustained speeds will lower to under 10 kt with the loss of daytime heating and mixing, becoming predominantly southeasterly. However, given a steep wind shift to the southwest and ultimately the west with a modest low- level jet aloft, low-level wind shear will likely become an issue for much of the night ahead of the front. But once the front passes and flow at the surface backs to the northwest early tomorrow morning (between 10-12z), wind shear will no longer be an issue. Then, as we begin to mix deeply tomorrow morning, northwesterly winds will increase to sustained 6-10kt with gusts up to 15-25kt.

Outlook:

Friday Night: No Operational Impact. NO SIG WX. Saturday: No Operational Impact. NO SIG WX. Saturday Night: No Operational Impact. NO SIG WX. Sunday: No Operational Impact. NO SIG WX. Sunday Night: No Operational Impact. NO SIG WX. Monday: No Operational Impact. NO SIG WX. Monday Night: No Operational Impact. NO SIG WX. Tuesday: Low Operational Impact. NO SIG WX.

Watches, warnings and advisories

CT: None. NY: None. MA: None. VT: None.