Thursday, September23, 2021
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Marine Weather and Tides
Portsmouth, NH

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.

Sunrise 6:30AMSunset 6:39PM Thursday September 23, 2021 2:32 PM EDT (18:32 UTC) Moonrise 8:06PMMoonset 9:02AM Illumination 94% Phase: Waning Gibbous; Moon at 17 days in cycle
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.
Marine Forecasts
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ANZ154 Coastal Waters From Cape Elizabeth, Me To Merrimack River, Ma Out 25 Nm- 1021 Am Edt Thu Sep 23 2021
.small craft advisory in effect from late tonight through Saturday morning...
Rest of today..SE winds 10 to 15 kt with gusts up to 20 kt. Seas 3 to 4 ft.
Tonight..SE winds around 15 kt with gusts up to 25 kt. Seas 3 to 4 ft. Areas of fog. Vsby variable to less than one quarter nm.
Fri..SE winds 15 to 20 kt with gusts up to 30 kt. Seas 4 to 5 ft. Areas of fog in the morning. A chance of showers in the morning, then showers likely with a chance of tstms in the afternoon. Vsby variable to less than one quarter nm, increasing to 1 to 3 nm in the afternoon.
Fri night..S winds 15 to 20 kt, becoming sw 10 to 15 kt after midnight. Seas 4 to 5 ft. A chance of tstms in the evening. Rain. Vsby 1 to 3 nm in the evening.
Sat..S winds 5 to 10 kt. Seas 3 to 4 ft. Scattered showers.
Sat night..S winds 5 to 10 kt, becoming sw after midnight. Seas around 3 ft. Rain likely.
Sun..SW winds 5 to 10 kt. Seas 3 to 4 ft. Scattered showers in the morning.
Sun night..W winds 10 to 15 kt. Seas 3 to 4 ft.
Mon..W winds 10 to 15 kt. Seas 3 to 4 ft.
Mon night..W winds around 10 kt. Seas 3 to 4 ft. Winds and seas higher in and near tstms.
ANZ100 1021 Am Edt Thu Sep 23 2021
Synopsis for stonington me to merrimack river ma out to 25 nm.. A prolonged period of southerly winds will continue over the waters through Friday as the region sits between offshore high pressure and a slowly approaching cold front from the west, bringing sca conditions. This front will cross the waters Friday night or Saturday with westerly winds developing in it's wake. Another cold front will drop towards the waters from the northwest by Monday or Tuesday of next week.


7 Day Forecast for Marine Location Near Portsmouth, NH
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location: 43.08, -70.77     debug


Area Discussion for - Gray/Portland, ME
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FXUS61 KGYX 231431 AFDGYX

Area Forecast Discussion National Weather Service Gray ME 1031 AM EDT Thu Sep 23 2021

SYNOPSIS. Warm and humid conditions for early fall continue across the forecast area ahead of a cold front. This front will very slowly cross the region late Friday and Saturday with a period of widespread rainfall likely, along with a few thunderstorms. Improving conditions are expected by the second half of the weekend as drier air arrives from the west. A cold front will then approach the region early next week with another threat for showers.

NEAR TERM /UNTIL 6 PM THIS EVENING/. 10:30AM Update . Mostly just tweaked temperature and cloud trends for today with this update, but overall the forecast remains on track. Still seeing some showers across the southern and southeast facing terrain, but otherwise most areas remain dry for today. Decided to go ahead and issue a SCA beginning late tonight through Saturday morning as the winds and seas increase overnight.

630AM Update . No significant updates to the forecast this morning with some small tweaks to the cloud cover. Overall fog development was limited last night compared to the previous mornings.

Today will be very similar to yesterday, with the exception of more breaks in the cloud deck, especially along the coastal plain. Current satellite shows the low level stratus deck remains across interior areas in favorable upslope areas, but breaks have formed in the coastal plain. Expect this trend to continue looking at near-term meso-model guidance. Expect a low chance for a passing shower with intermediate periods of clouds as a few showers develop, with the highest likelihood across the foothills and mtns. of NH. Temps will remain above average after a very warm start to the day as low temps remained mostly in the mid-60s. Highs should top out in the mid to upper 70s, with a few locations touching the 80 degree mark. Marine stratus should make another push by this evening as the low level jet begins to increase in strength as the surface cold front approaches from New York.

SHORT TERM /6 PM THIS EVENING THROUGH 6 PM FRIDAY/. The cold front begins to approach the area tonight as the closed 500mb low over the Great Lakes begins to move north. This will cause the low level jet to increase with 925mb winds increasing to 35kts. Most models are showing an increased surge of low level moisture as PWAT anomalies begin to increase. This should allow for an increase in stratus formation and possible coastal fog. Mid-level heights also begin to lower as the 500mb ridge over the North Atlantic begins to shift further east after midnight. The combination of these two factors should allow for increase in rain shower activity, especially over the Whites. By Friday morning the frontal boundary finally begins to push into the CT River Valley. This boundary will be the focus for moderate rainfall with most areas receiving a 3 to 4 hour window of rainfall. Overall amounts will range from .75" to 1.25" with locally up to 2" across the southeastern slopes of the Whites and Western Maine mtns. Currently the flash flood threat looks low but can't totally be ruled out at this time, especially if the frontal boundary stalls out earlier than the current model consensus. The second weather threat we are watching on Friday is the potential for Severe Weather across mostly NH at this time along the frontal boundary. SPC has the region under a Marginal risk at this time for the potential of gusty winds and a low Tor threat. Overall dynamics look strong with strong shear profiles and favorable hodographs, but how much surface based instability can be mustered on Friday due to sufficient low level cloud cover is the largest deterrent. Most sounding profiles due support some marginal instability with CAPE values in the 400-900 J/KG range across southern NH. Hodograph profiles are classic with a SE veering wind profile and low LCL heights. Will have to watch how this trends over the next 24hrs, but have kept the mention of this threat in the HWO.

LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/. Overview: Upper low will lift thru the Ern Great Lakes to start the weekend . while an upper trof tries to establish itself over the Ern CONUS. Generally unsettled weather and seasonable temps are expected into next week.

Impacts: Frontal boundary will stall over or E of the forecast area . allowing moderate to occasionally heavy rain to threaten thru Sat.

Forecast Details: Front will continue its slow march across the forecast area Fri night. Upper low lifting into Canada and strong ridging to the E will start to allow the boundary to stall thru the night. The good news is that as the best forcing lifts into Canada the intensity of rainfall should weaken as well.

The real question is how much progress does the front make before stalling The 23.00z GFS is the most progressive. taking the boundary to near New Brunswick before coming to a stop. The 23.00z ECMWF meanwhile keeps the boundary hung up across our forecast area. This is important because there will be a follow up S/WV trof that will support the development of a secondary precip shield . one that may entrain moisture from Peter. At this time the ECMWF EPS is fairly aggressive on that scenario affecting at least the Ern half of the forecast . while roughly 50 percent of GEFS members have a second wave of rainfall impacting Wrn ME. As such I have kept likely or higher PoP going thru Sat into Sat night . especially NE of PWM.

Once that S/WV trof kicks the front out of the area for good the pattern will be dominated by mean trofing. This will keep temps seasonable . with frequent chances for showers in the higher terrain in W/NW flow.

AVIATION /15Z THURSDAY THROUGH MONDAY/. Short Term . Aviation conditions will be improving this morning across the region with MVFR cigs scattering out today for most TAF locations by mid-morning with the possibility of tempo MVFR cigs due to a few passing light rain showers. A return to IFR conditions is likely tonight as onshore flow continues and enhances as the surface cold front begins to approach the region from the west, this will allow for lowering ceilings across the region. By Friday the cold front will slowly move from west to east across the area with an expected 3 hr window of moderate rain at each TAF location as it progresses eastward. The possibility exists for a few embedded thunderstorms across NH TAF sites on Friday afternoon. Brief heavy downpours can also be expected.

Long Term . Areas of IFR or lower conditions remain possible Fri night into Sat as a cold front slowly marches across the forecast area. Should see some improvement especially across NH terminals Fri night into early Sat. However Midcoast ME will see the best chance for rain and IFR or lower conditions Sat and Sat night . including AUG and RKD. Conditions will gradually improve to VFR Sun and Mon . with a chance of lingering MVFR CIGs at HIE in upslope flow.

MARINE. Short Term . Similar weather pattern over the waters today, with confidence for fog bank development today low, but this should increase later tonight as the surface cold front begins to approach the Gulf of Maine from New York, bringing with it an additional surge of moist low level moisture. The possibility of dense fog, especially for Penobscot Bay area increases on Friday. In addition winds will be on the increase and should begin to flirt with SCA conditions by late tonight with SCA conditions possible on Friday with 25kt onshore wind gusts and waves building to 5 ft.

Long Term . Persistent SE flow ahead of approaching cold front will see a few 25 kt wind gusts but seas remaining above 5 ft into Sat. Seas will very slowly diminish thru the day. Areas of dense fog are also possible ahead of the front . as tropical moisture surges Nwd. Generally dry offshore flow will develop for the latter half of the weekend and continues into early next week.

GYX WATCHES/WARNINGS/ADVISORIES. ME . None. NH . None. MARINE . Small Craft Advisory from 5 AM Friday to 8 AM EDT Saturday for ANZ150>154.

SYNOPSIS . Clair NEAR TERM . Clair SHORT TERM . Clair LONG TERM . Legro AVIATION . Clair/Legro MARINE . Clair/Legro


Weather Reporting Stations
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Stations Dist Age Wind Air TempWater Temp WavesPressureDewPt
BGXN3 - Great Bay Reserve, NH 3 mi107 min SE 4.1 79°F 1020 hPa70°F
IOSN3 - Isle of Shoals, NH 11 mi32 min SE 21 G 22 68°F 1018.2 hPa (-0.7)67°F
44073 13 mi148 min SE 14 G 16 69°F
44030 - Buoy B0102 - Western Maine Shelf 19 mi88 min SSE 12 G 16 66°F 64°F4 ft1020 hPa
WELM1 - 8419317 - Wells, ME 20 mi44 min S 4.1 G 8 70°F 64°F1020.1 hPa
WEXM1 - Wells Reserve, ME 21 mi92 min S 2.9 73°F 67°F
44098 - Jeffrey's Ledge, NH (160) 37 mi36 min 66°F3 ft
44029 - Buoy A0102 - Mass. Bay/Stellwagen 40 mi88 min SE 14 G 16 67°F 3 ft1018.7 hPa
44007 - PORTLAND 12 NM Southeast of Portland,ME 45 mi22 min SSE 12 G 14 66°F 65°F1019.3 hPa63°F
CASM1 - 8418150 - Portland, ME 49 mi44 min 71°F 62°F

Wind History for Wells, ME
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Airport Reports
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AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Pease Air Force Base / Portsmouth, NH3 mi36 minSE 16 G 2010.00 miMostly Cloudy74°F64°F70%1019.5 hPa
Rochester - Skyhaven Airport, NH16 mi41 minSE 9 G 1410.00 miMostly Cloudy77°F68°F74%1018.6 hPa
Sanford, Sanford Regional Airport, ME22 mi36 minS 8 G 1510.00 miMostly Cloudy75°F66°F74%1019.9 hPa

Link to 5 minute data for KPSM

Wind History from PSM (wind in knots)
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1 day agoSE10SE10SE10SE8E7E4SE5SE4SE3SE3SE2SE2SE2SE1CalmCalmCalmCalmSE6SE10SE10SE11SE12SE9
2 days agoSE6SE9SE11SE9SE7SE5SE4CalmCalmCalmCalmCalmCalmCalmNW3CalmCalmCalmCalmW3CalmS10SE9SE8

Tide / Current Tables for Atlantic Heights, Piscataqua River, New Hampshire
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Atlantic Heights
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Thu -- 01:47 AM EDT     8.02 feet High Tide
Thu -- 06:31 AM EDT     Sunrise
Thu -- 07:44 AM EDT     0.22 feet Low Tide
Thu -- 09:02 AM EDT     Moonset
Thu -- 02:03 PM EDT     7.99 feet High Tide
Thu -- 06:38 PM EDT     Sunset
Thu -- 08:05 PM EDT     Moonrise
Thu -- 08:06 PM EDT     0.12 feet Low Tide
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.

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6.77.787.35.73.61.70.50.212.54.46.27.587.66.24.22.20.70.10.51.73.5

Tide / Current Tables for Portsmouth Harbor Entrance, New Hampshire Current
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Portsmouth Harbor Entrance
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Thu -- 02:46 AM EDT     -0.00 knots Slack
Thu -- 05:34 AM EDT     -1.93 knots Max Ebb
Thu -- 06:31 AM EDT     Sunrise
Thu -- 09:01 AM EDT     Moonset
Thu -- 09:22 AM EDT     0.00 knots Slack
Thu -- 11:24 AM EDT     1.25 knots Max Flood
Thu -- 03:11 PM EDT     -0.00 knots Slack
Thu -- 05:57 PM EDT     -1.89 knots Max Ebb
Thu -- 06:37 PM EDT     Sunset
Thu -- 08:05 PM EDT     Moonrise
Thu -- 09:48 PM EDT     0.00 knots Slack
Thu -- 11:43 PM EDT     1.13 knots Max Flood
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.

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10.90.6-0.2-1.2-1.8-1.9-1.7-1.2-0.40.61.21.210.70.2-0.8-1.6-1.9-1.7-1.4-0.80.21

Weather Map
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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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