Marine Weather and Tide Forecast for Poughkeepsie, NY

SHORT TERM /6 AM THIS MORNING THROUGH TUESDAY NIGHT/
Key Messages:

- Flood Watch issued for areas south and east of the Capital District today, where isolated to scattered flash flooding is expected.

- Heat index values are expected to approach advisory criteria (95F) Tuesday for most valley areas.

Discussion: As of 2:35 AM EDT...Occluded sfc low is now located over Hudson Bay, while looking aloft upper ridging is departing into the North Atlantic and broad troughing from upstream is track eastwards. A weak cold frontal boundary associated with the sfc low remains located back to our west near the Great Lakes. Ahead of this boundary, convection from yesterday evening is still ongoing across the Catskills, but has been weakening due to limited instability. While some heavy rain is possible across the Catskills over the next couple of hours, the heaviest rain with this convection will likely remain south of our region.
Otherwise, the remainder of tonight looks warm and muggy yet again. With low-level southeasterly flow, low stratus should keep expanding north and west through the remainder of the night. A light breeze, high dew points, and increasing cloud cover should help keep overnight lows mainly in the mid to upper 60s for valley areas and low 70s for the valleys. Patchy fog is also expected given the very moist airmass.

Today, the slow-moving cold frontal boundary continues to slide eastwards into our region. At the same time, an upper impulse embedded within the broader upper trough will arrive from the west this afternoon, as will diffluent upper flow and the right entrance of a weak jet streak tracking north of the region.
These features will all help provide forcing for ascent. Given that we remain in a very moist and unstable airmass, additional scattered to numerous showers and thunderstorms are expected today, especially from the Capital District south and east.
There remains some uncertainty how far north and west convection will occur today, especially with the ongoing nighttime convection to our west that has made it further south and east than most CAMs were suggesting. The biggest threat with any storms today will be heavy rain leading to flash flooding. More details can be found in the hydro section below, but will mention here that we did consider including Schoharie, Albany, and Rensselaer Counties in the FFA, but ultimately decided not to per collaboration with WFO BGM and based on current convective trends on radar. Timing for showers and storms looks to be from noon through this evening.

While heavy rain is the primary hazard, SPC has continued the marginal risk for severe storms as well. SBCAPEs should climb to 1500-2000 J/kg per the latest HRRR. Shear looks weak and DCAPES aren't all that impressive, but with a very moist airmass in place the environment looks favorable for precip loading leading to a few wet microbursts from the Capital District south and east this afternoon. Given high freezing levels and lack of shear, wind will be the main severe threat this afternoon.

Convection slowly diminishes this evening after sunset with decreasing instability, but may linger into tonight near the I-84 corridor closer to the frontal boundary. A very slightly cooler/drier airmass will be overhead tonight, so temps and dew points will end up a couple degrees below those from the last few nights. Patchy fog will be possible once again, especially for areas that see rain today.

Tuesday, high pressure builds in from the west as broad ridging amplifies aloft. The main story will be increasing temperatures beneath the building ridge. Highs look to be in the upper 80s to low 90s for many valley areas. There will be a lot of mid-level dry air around that can be mixed down, so while dew points will be elevated they will not be as high as the last few days.
Accordingly, heat indices will likely be in the low to mid 90s.
Heat advisories may be needed for some valley areas Tuesday, but it looks very borderline at this point. With large-scale subsidence, most of the region should be dry. The exception is for a few isolated showers or a thunderstorm near the I-84 corridor, where the frontal boundary will remain stalled. With the surface high still overhead Tuesday night, we should see temperatures drop to near the respective dew points, with low to mid 60s in the high terrain and mid 60s to around 70 for the valleys. Patchy fog will be possible once again.

LONG TERM /WEDNESDAY THROUGH SUNDAY/
Key Message:

- Heat Index values or "feels-Like" temperatures will likely reach the mid 90s to around 100 in the valley areas for the middle to end of this week.

- Watching Thursday - Friday for increased chances for thunderstorms and potential severe weather.

Discussion:

Wednesday, the upper ridge and warmest airmass aloft will be over our region. 850 temps reach +18 to +20C, which will translate to daytime highs in the low to possibly mid 90s for valley areas. The surface high slides off to our east, so we get into more of a southerly flow regime, which will result in dew points rising as well. Heat advisories will likely be needed for many valley areas Wednesday. While most of the day should remain dry with it being so warm aloft under the ridge, a few afternoon showers or thunderstorms could develop given the soupy airmass.
The better chance will be Wednesday evening or night when an upper impulse is expected to approach from the west and may provide some forcing for ascent for a few more showers and storms. Wednesday night will be very warm and muggy with lows in the upper 60s to mid 70s.

We are beginning to see more clarity into the setup for the end of the week, although details are still uncertain at this lead time. Thursday looks to remain hot and quite humid across the region, and additional heat advisories may be needed again.
At this time, guidance is starting to come into better agreement in a surface low tracking north of our region Thursday, with a pre-frontal trough potentially providing forcing for the development of showers and thunderstorms across eastern NY into western New England. It then looks like the actual cold front will track through our region Friday, with potentially another round of showers and storms. While the threat for severe weather and heavy rain will ultimately depend on how the timing of these features coincides with peak diurnal heating, the airmass will be quite moist and unstable ahead of this cold front. Shear also looks to increase with strengthening westerly flow aloft, so this certainly bears watching over the next several days.
There is still good agreement for high pressure to bring drier, cooler, and less humid weather behind this front for next weekend.

AVIATION /06Z MONDAY THROUGH FRIDAY/
Through 06z Tuesday, weakening area of showers may bring some MVFR Vsbys between 06Z-09Z/Mon. Otherwise, low clouds streaming northward should allow Cigs to lower into the MVFR/IFR categories by 09Z/Mon, lingering until 14Z-17Z/Mon. Mainly VFR conditions are expected this afternoon outside of scattered showers/thunderstorms, where areas of brief MVFR/IFR Vsbys will be possible. Best chances for showers/thunderstorms looks to be 17Z-24Z/Mon, with earlier timing at KGFL and KALB. Some showers/thunderstorms may linger until 02Z/Tue at KPOU/KPSF.
Areas of MVFR/IFR Cigs/Vsbys may develop after 02Z/Tue in areas which receive prior heavy rainfall.

South to southeast winds 5-10 KT are expected overnight through Monday. Winds will be stronger and variable in direction in/near any thunderstorms.

Outlook...

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

HYDROLOGY
Coverage of rain and thunderstorms with locally heavy downpours increases this afternoon, mainly from the Capital District south and east. WPC has maintained their slight risk ERO for this area, and we have issued a flood watch for portions of the Mid Hudson Valley, eastern Catskills, Taconics, and western CT/MA from noon through 06z tonight. Very deep warm clouds, PWATs potentially in excess of 2" (which is 2-3 standard deviations above normal) will promote the potential for very heavy rainfall rates in excess of 2" per hour with any afternoon showers and storms. Mid-level flow looks relative slow, and the flow will be parallel to the approaching frontal boundary so we may have some backbuilding and/or training of convection this afternoon. The 00z HRRR has a 10% chance for 3" of rain in 3hrs for areas south and east of the Capital District, which is often a good signal for an elevated flash flood threat. Relatively dry conditions over the last 3 days may help mitigate the flash flood threat somewhat. Nevertheless, the threat will be greatest for the more urban areas, as well as poor-drainage and low- lying areas.

ALY WATCHES/WARNINGS/ADVISORIES
CT...Flood Watch from noon EDT today through late tonight for CTZ001-013.
NY...Flood Watch from noon EDT today through late tonight for NYZ058>061-063>066.
MA...Flood Watch from noon EDT today through late tonight for MAZ001-025.
VT...None.