Marine Weather and Tide Forecast for Rhinecliff, NY

KEY MESSAGES
1. Isolated to scattered severe thunderstorms this afternoon into this evening threaten to bring locally damaging wind gusts and large hail that could cause property damage and possible power outages.

2. Isolated to widely scattered severe thunderstorms are possible on Wednesday south of the Capital Region.

3. The threat for widespread impactful weather is low from Thursday through the end of the weekend.

DISCUSSION
KEY MESSAGE 1...

The latest SPC hourly mesoscale analysis page shows a mid-level, relatively compact shortwave trough just north of the eastern Great Lakes, embedded within quasi-zonal flow. At the surface, a weak wave/low rests along a quasi-stationary boundary oriented horizontally across northern New York, just outside our northern CWA boundary. The core of the surface wave/low currently resides just on the opposite side of the international border in deep, southeast Ontario with an anticipated eastward trajectory along the boundary through this evening.

Scattered showers and thunderstorms have already entered and swiftly departed the Southern Adirondacks late this morning into early this afternoon as a result of an initial surface wave/lake-shore boundary off Lake Ontario, though an overall lack of instability and forcing led quickly to their demise before vertical growth was sufficient enough to allow them to pose any concern. Quite frankly, that is our primary concern with the overall severe threat across the region this afternoon into this evening: lack of forcing. While areas south of the Southern Adirondacks have, with moisture advection and breaks of sun amid an already anomalously warm airmass, attained SBCAPE values on the order of 500 to 1000 J/kg, the lack of strong forcing may ultimately win out over sufficient destabilization for widespread non-severe and severe convection.

Amid extensive data interpretation, including that of latest radar trends, the conclusion has been drawn that the best opportunity, or threat, for severe-level convection comes mid this afternoon into this evening when the eastward track of the aforementioned shortwave will intersect that of the surface wave along the northern boundary. As these two features further approach our region, some of the HiRes guidance has indicated that a local vorticity maximum, though a weakening one at that, will also slide eastward, increasing the vertical stretching and subsequently the upward lift along and just south of the boundary. Increased surface convergence from both the boundary and the eastward-propogating surface wave should align well with this vort max to provide sufficient forcing for ascent for areas along and just south of the boundary. However, with the surface wave extending well off the boundary and the upper shortwave sinking slightly farther south along its eastward progression, forcing for ascent across the unstable environment will subsequently increase, aiding in maintaining any developing convection much farther south.

Should the surface wave extend farther, hence expanding the risk for developing and sustaining convection, SBCAPE values rising widely to 1000 J/kg, if not pockets of values in excess of that, 0-6km bulk shear on the order of 40-50 kt, and steep mid-level lapse rates of about 6-7 C/km will be supportive of severe thunderstorm development. In fact, an isolated supercell thunderstorm or two cannot be ruled out particularly within and north of the Capital District. 1 and 6 km shear vectors oriented nearly 45 degrees and parallel to environmental hodographs respectively indicate that storm mode should initially begin cellular before potentially congealing further downstream into clusters, if not line segments. The latest scans of the KENX radar support this thought, as cellular structures can be seen pulsing through the Southern Adirondacks. Certainly, should any strong cells or supercells form, cool outflow could enhance cold pools and help create some nearby bowing of clusters or linear segments should they be adjacent enough to tap into those environments. Additionally, any developing outflow boundaries could also be a focus for additional convection further downstream.

Within supercellular convection, large hail and damaging winds are going to be the primary threats. Should an updraft be sufficient enough (strong enough) to loft hailstones for prolonged periods of time, there could certainly be come 1" hailstones in some areas. The limiting factor here is shorter upper-level segments of the environment hodographs which indicate there may be a short shelf life of stones within the updraft. Inverted-V soundings from well-mixed environments as well as high DCAPE (~300-800 J/kg) and aforementioned steep mid-level lapse rates also indicate the potential for damaging wind gusts. An isolated tornado closer to the boundary, or within the Southern Adirondacks, also cannot be ruled out as storm relative helicity is on the moderate side and convergent, low-level winds could drive some low and mid-level turning.
Should supercells develop, mid-level mesocyclones could drop given lower LCLs. But, as previously stated, this is much more of an isolated threat.

Now, for those reasons, scattered severe convection is favored across the region this afternoon into this evening. However, the lack of slabular forcing from a true frontal passage and upper- level dynamic forcing in the absence of a large scale or even more potent shortwave trough, should significantly limit the spatial extent or coverage of severe storms during the aforementioned target time. Additionally, there remains uncertainty as to how far south the surface wave will extend. If it is shunted farther north, severe-level convection will be very difficult to attain. Or, rather, will be very difficult to maintain much farther south of the boundary despite the favorable environmental indices. Finally, as currently seen on the SPC hourly mesoscale analysis page, the rain-cooled air and cool outflow from storms could also stabilize the environment, hindering further development later if we cannot destabilize again in these areas. But, we are monitoring the trends of the situation closely and will ultimately issue any severe thunderstorm warnings as necessary.

KEY MESSAGE 2...

Another shortwave trough will track through the mean, zonal flow tomorrow, bringing additional rounds of showers and thunderstorms. With today's quasi-stationary boundary still present, just a bit further south, and another surface wave riding along it, there could be some isolated severe thunderstorms, particularly in the Eastern Catskills where a Marginal Risk for severe weather currently exists. The primary threat with these will also be strong to locally damaging wind gusts, but the threat looks much more subdued compared to today.

KEY MESSAGE 3...

Additional disturbances will force a rinse-and-repeat type pattern through the end of the week with rounds of additional showers and non-severe thunderstorms amid a persistent, warm environment. Temperatures will continue to run above normal until late this weekend into early next week when a fairly potent cold front sweeps through the region and brings us actually to below-normal levels by Monday. That said, the overall probability for impactful weather is low from Thursday through early next week.

AVIATION /19Z TUESDAY THROUGH SUNDAY/
Through 18z Wednesday...VFR conditions at all terminals as of 1:15 PM EDT should prevail through the next few hours. Then, chances for scattered showers/thunderstorms increase later this afternoon and evening. Confidence remains fairly low on coverage of showers/storms, but we did attempt to narrow down the timing of showers/storms from the previous TAF issuance. Given current observations and trends, GFL still has the best chance to see a shower/storm, but chances for ALB/PSF/POU look slightly lower than when the 12z TAFs were issued, so we have made some adjustments to tempo and prob30 groups to reflect this. Gusty winds and IFR vsbys possible with any showers/storms.

Showers/storms come to and end this evening by 00-02z. Then, mainly VFR conditions through the first half of the night with SCT to BKN mid-level clouds. Cigs trend down to MVFR at ALB/GFL/PSF for the second half of the night. If any of these terminals see a shower/storm with appreciable rainfall this evening, then some localized fog/mist and IFR conditions can't be ruled out later tonight. Flying conditions trend back up to VFR for most of tomorrow morning, outside of a batch of showers that could bring some MVFR vsbys/cigs towards the end of the TAF period.

Outlook...

Wednesday Night: High Operational Impact
Likely SHRA
TSRA.
Thursday: Moderate Operational Impact
Chance of SHRA
TSRA.
Thursday Night: Moderate Operational Impact
Chance of SHRA
TSRA.
Friday: High Operational Impact
Likely SHRA
TSRA.
Friday Night: Moderate Operational Impact. Chance of SHRA.
Saturday: No Operational Impact. NO SIG WX.
Saturday Night: Moderate Operational Impact. Chance of SHRA.
Sunday: High Operational Impact. Breezy. Likely SHRA.

CLIMATE
Record High Temperatures(Year Set):

Today April 14: Albany: 89(2023)
Glens Falls: 84(2023)
Poughkeepsie: 91(2023)

Wednesday April 15: Albany: 86(2003)
Glens Falls: 84(2003)
Poughkeepsie: 84(2003)

Thursday April 16: Albany: 91(2012)
Glens Falls: 89(2002)
Poughkeepsie: 91(2012)

ALY WATCHES/WARNINGS/ADVISORIES
CT...None.
NY...None.
MA...None.
VT...None.