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Marine Weather and Tides Willow Street, PA Version 3.4

NOTICE 3/30/2021 -- ANZ330 has been split into ANZ331 and ANZ332. Click EDIT in Marine Forecast and select your new zone. 1/26/2021 -- The West Coast Satellite images havd been updated. They now use GEOS-17. 1/1/2021 -- The 7 day forecast are now working well. Thank you NOAA for your support.

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Sunrise 5:59AM

Sunset 8:23PM

Thursday July 29, 2021 4:59 AM EDT (08:59 UTC)

Moonrise 10:43PM

Moonset 10:46AM

Illumination 75%

NOTE: Some of the data on this page has not been verified and should be used with that in mind. It may and occasionally will, be wrong. The tide reports are by xtide and are NOT FOR NAVIGATION.

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7 Day Forecast for Marine Location Near Willow Street, PA

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Area Discussion for - State College, PA

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FXUS61 KCTP 290822 AFDCTP

Area Forecast Discussion National Weather Service State College PA 422 AM EDT Thu Jul 29 2021

SYNOPSIS. The conditional risk of severe thunderstorms continues to increase this afternoon and evening with a wind damage and isolated tornado threat focused over south-central Pennsylvania. A northwest breeze will bring dry and more comfortable air into the area on Friday which will set the stage for a refreshing cooldown to close out July 2021.

NEAR TERM /THROUGH TONIGHT/. Quiet start today with patchy fog/stratus in the Susquehanna Valley and multi-layer clouds increasing over the western portion of the area. Also cannot rule a couple of showers in this area through daybreak.

The conditional risk of severe storms ramps up this afternoon and evening (2-8PM most likely timing) with SPC upgrading the south- central and southeast zones to an Enhanced risk (level 3 out of 5). The upper pattern will be characterized by a broad trough/cyclonic flow aloft with embedded MCV translating east- southeastward from the southern Great Lakes through the northern Mid Atlantic region.

29/00Z HREF mean shows 40-50kt deep-layer shear profiles in place later this afternoon with 0-3km SRH values 200-400+ m2s2. The main uncertainty driving the conditional nature of this potentially significant severe wx event continues to center around the degree of destablization, as cloud cover from upstream convective complex may limit heating/instability to some extent. The latest HRRR and other CAMs show pcpn from this feature reaching into the western zones between 15-17Z.

Assuming sufficient CAPE can be realized in the warm sector, the environment will be supportive of some supercells that may evolve into bowing structures as storms track northwest to southeast during the afternoon and evening. While the primary threat appears to be damaging winds and possibly some hail, low level hodographs are supportive of an isolated tornado risk especially in the vicinity of sfc warm front over south- central PA. This risk is highlighted by a 5% tornado probability.

MaxT will be a few to several degrees lower vs. yesterday in the low 70s north to lower 80s south. The relatively cooler temps combined with advection of rich low level moisture (near-70F dewpoint air) suggests lower LCL heights which are an important delineator for tornadoes in central PA. Despite PW values around 1-1.5 inches supporting brief heavy downpours/rain rates, recent dryness in the past 7 days along with fairly progressive storm motions should confine flooding risk to marginal (level 1 out of 4) with the highest probs/lowest FFG in the NC/NE mtns.

The severe threat should end by 8PM give or take, but showers could linger in spots for most of the night. MinT will trend a few degrees warmer overall with the largest positive 24hr deltas over the middle and upper Susquehanna Valley. Post-frontal NW flow should align low clouds upslope along the western Alleghenies into early Friday morning.

SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/. Improving conditions are expected in the wake of the cold FROPA Friday with much drier air poised to arrive via refreshing NW breeze. Look for a mix of sun and clouds and low humidity. The latest model data suggests a passing shower is possible mainly across the NE zones under the cool pocket aloft, but this may be more diurnal cu vs. pcpn that actually reaches the ground given dewpoints dropping into the 40s.

The dry/low PW airmass will set the stage for a rather cool Friday night/AM Saturday with minTs ranging from the mid 40s over the NW Alleghenies to the mid 50s across the southeast valleys (good sleeping weather!). We were keen to shade Td lower during the day Friday and weight minTs Friday night toward the low end of the NBM range. MaxT Friday will be about 5-10F below daily climo. Look forward to a beautiful start to the weekend and last day of July 2021. The next cold front is fcst to settle down across the lower Great Lakes by Sunday morning with NBM PPIs signaling low precip probs across the NW mtns by 12Z Sun.

LONG TERM /SUNDAY THROUGH WEDNESDAY/. Evening update: No significant changes made in this update.

Shortwave trough pushing south across Ontario on Saturday will lead to backing flow aloft as modest return flow sets up for late Saturday and Sunday, spelling the return of shower chances across the Alleghenies late Saturday. A better shot for showers/storms will exist for all of central PA on Sunday as a surface low moves across Lake Ontario.

Much of Monday should remain dry, outside of a few lingering early day showers across the northern tier. Another upper low looks to dig into the western Great Lakes/Midwest into Tuesday, which will once again lead to increasing moisture and subsequent shower/storm chances into midweek. Below normal temperatures look to remain the rule, with highs generally in the low 70s north to low 80s south and lows spanning the 50s with low 60s in the lower Susquehanna Valley.

AVIATION /07Z THURSDAY THROUGH MONDAY/. Mainly VFR expected through sunrise, except for a period of MVFR cigs early this morning at LNS, MDT, and perhaps IPT in moist SE flow ahead of a low pressure system approaching from the Great Lakes. That low will bring showers and storms late in the morning and afternoon for most terminals with widespread reductions in cigs and visbys. There is the potential for a few TSRA with gusty winds in the afternoon as well, especially for southern terminals.

A cold front will cross through northern terminals AOB 00z Fri and continue through southern terminals by 06z Fri. This will bring an end to TSRA activity but MVFR or IFR cigs will likely persist at BFD and JST into Fri morning in moist upslope NW flow.

Outlook .

Fri & Sat . No sig wx expected.

Sun . Chance of a shower or thunderstorm.

Mon . Mostly VFR

CLIMATE. It's been a wet July in some parts of central PA. Through July 28th, the monthly precipitation at Harrisburg is 7.99 inches which currently ranks 2021 as the 9th wettest July on record.

CTP WATCHES/WARNINGS/ADVISORIES. None.

SYNOPSIS . Steinbugl NEAR TERM . Steinbugl SHORT TERM . Steinbugl LONG TERM . Guseman/Ross/DeVoir AVIATION . Colbert/Travis CLIMATE . Steinbugl

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Weather Reporting Stations

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Stations	Dist	Age	Wind	Air Temp	Water Temp	Waves	Pressure	DewPt
CHCM2 - 8573927 - Chesapeake City, MD	39 mi	60 min	ENE 4.1 G 5.1	70°F	83°F		1016.3 hPa (-0.0)
DELD1 - 8551762 - Delaware City, DE	45 mi	60 min	WSW 1 G 2.9	72°F			1016.1 hPa (-0.3)
MRCP1 - 8540433 - Marcus Hook, PA	47 mi	60 min		72°F	81°F		1015.8 hPa (-0.3)
RDYD1 - 8551910 - Reedy Point, DE	47 mi	60 min		72°F	83°F		1015.6 hPa (-0.3)

Wind History for Chesapeake City, MD

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Airport Reports

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Airport	Dist	Age	Wind kt	Visibility	Sky/Weather	Temp	DewPt	Humidity	Pressure
Lancaster, Lancaster Airport, PA	10 mi	67 min	E 4	5.00 mi	Fog/Mist	68°F	64°F	87%	1015.5 hPa
Chester County Airport, PA	21 mi	65 min	ESE 3	10.00 mi	Partly Cloudy	68°F	66°F	94%	1017.3 hPa

Link to 5 minute data for KLNS

Wind History from LNS (wind in knots)

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Tide / Current Tables for Port Deposit, Susquehanna River, Maryland

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Tide / Current Tables for Havre de Grace, Susquehanna River, Maryland

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Weather Map

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GEOS Local Image of    EDIT
NOTE: This section has been updated as of 1/26/2021. If the image you are expecting is not showing, please let me know. You may use the EDIT function to update your location.
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