Wednesday, August16, 2017 L-36.com


Marine Weather and Tides
Portsmouth, NH

Version 3.4
What's New / NOTES
6/25/2017 - NOAA is having a major issue that impact the 7 day forecast load times. Many users are reporting problems. The issue has been reported.
5/23/2017 - Worked with NOAA again to speed up the 7 day forecast load times. Thanks to them for being responsive.
5/19/2016 - There were issues with the 3 day airport observation history. I switched to another data source. Let me know if you see any issues with the data feeds.

Sunrise 5:49AMSunset 7:44PM Wednesday August 16, 2017 11:22 AM EDT (15:22 UTC) Moonrise 12:30AMMoonset 3:19PM Illumination 31% Phase: Waning Crescent; Moon at 24 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- 922 Am Edt Wed Aug 16 2017
Today..NW winds 5 to 10 kt. Seas 2 to 3 ft.
Tonight..NW winds 5 to 10 kt. Seas 2 to 4 ft.
Thu..W winds 5 to 10 kt, becoming sw with gusts up to 20 kt in the afternoon. Seas 3 to 5 ft.
Thu night..SW winds 5 to 10 kt with gusts up to 20 kt, becoming N after midnight. Seas 2 to 4 ft.
Fri..SE winds 5 to 10 kt. Seas around 2 ft.
Fri night..S winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to 3 ft, building to 3 to 5 ft after midnight. Showers likely in the evening, then showers with a chance of tstms after midnight. Vsby 1 to 3 nm.
Sat..S winds 10 to 15 kt with gusts up to 20 kt. Seas 4 to 6 ft. A chance of showers.
Sat night..SW winds 5 to 10 kt with gusts up to 20 kt. Seas 4 to 6 ft. A chance of showers.
Sun..W winds 5 to 10 kt. Seas 2 to 4 ft.
Sun night..W winds 5 to 10 kt. Seas 2 to 3 ft. Winds and seas higher in and near tstms.
ANZ100 922 Am Edt Wed Aug 16 2017
Synopsis for stonington me to merrimack river ma out to 25 nm.. High pressure approaching the region today and cresting over the region on Thursday will give way to a low pressure system moving in from the west Friday. Hurricane gert will remain well offshore with swell impacting our region.

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 161411 cca
afdgyx
area forecast discussion... Corrected
national weather service gray me
1011 am edt Wed aug 16 2017

Synopsis
Northwesterly flow will bring drier air to the region today.

High pressure crests over the region through Thursday. Low
pressure will move through the great lakes late in the
week... And send a warm front through the region late Friday.

Showers will be possible along the warm front... And then again
Saturday as the cold front follows behind it. High pressure will
build back in for early next week.

Near term until 6 pm this evening
920 am update... Quiet weather across the forecast area this
morning as high pressure centered north of the western great
lakes builds south and east towards the region with deep layer
subsidence overhead. Have updated near term temperatures to
match observations... Where values are increasing more rapidly
than inherited forecast. 12z gyx RAOB shows plenty of room for
drying and will lower dewpoint some in line with near term
mesoscale guidance... With dewpoints falling back into the 40s
see similar values already showing up north of the
international border . Otherwise... Only very minor changes to
the forecast.

Original discussion below...

overnight shower activity has fallen apart as the weak cold
front pushes into our area. With moist dewpoints in the 50s
expect fog to continue to form through dawn, with some dense fog
in the favored valley locations.

Today will see valley fog dissipate after sunrise. Increasing
northwesterly flow will bring drier air into the region during
the day. The pressure gradient will be just strong enough to
keep the seabreeze at bay and a few gusts to around 20kts are
possible in the coastal plain this afternoon.

Short term 6 pm this evening through 6 pm Thursday
Overnight high pressure builds over the region. Clear and dry
conditions will allow for good radiational cooling as the
atmosphere decouples. Widespread overnight lows in the 40s will
be the result. With dewpoints preventing the temperatures from
falling further, expect patchy fog in the valleys by morning.

Thursday will once again be sunny as high pressure remains
overhead. The upper low will remain to our northeast once again
keeping steady northwesterly flow across the region. Highs will
be near 80 south to 70 north.

Long term Thursday night through Tuesday
Surface ridging will be in place to start the period across nrn
new england. Aloft... The ridge axis is not forecast to cross the
region until at least midday fri. So I think precip will have a
tough time moving in developing until that as shifted to our e.

On the boundary of the WAA aloft and departing ridge... There may
be a band of showers that moves thru. More likely the narrow
warm sector will develop into more of an occlusion Fri night
with a more strongly forced band of showers and embedded
thunder. Models forecast some sharp drying aloft behind
this... So rainfall should come to a quick end from W to E into
early sat. The main cold front will not cross the area until
later in the day... So the threat of more isolated convective
precip will remain in the forecast until then.

Main cold pool swings thru aloft on sun... So it could be a day
of destructive sunshine where insolation leads to development of
more clouds. Lingering moisture in the cyclonic flow over the
terrain should also keep the mtns in the clouds with an isolated
shower or two.

Early next week high pressure will build to the S of the region.

At this time it looks like it will reach far enough N to keep
any frontal boundaries N of the forecast area. That high will
gradually drift ewd thru the week... And by midweek SW return
flow is expected over the area as the next trof and frontal
boundary approach the region from the w.

Aviation 13z Wednesday through Sunday
Short term... Overnight valley fog will result in ifr to lifr
conditions through dawn today and again tonight. OtherwiseVFR
will prevail as high pressure moves over head.

Long term... As warm front lifts towards the area and flow
becomes onshore... Conditions will deteriorate to MVFR or lower
across the area. Conditions near the coast will need to be
watched... As some coastal fog stratus is possible. At this time
it looks like front will be delayed enough that stratus will
have a smaller window to move into coastal NRN new england. Cold
front will sweep across the forecast area sat... And local ifr
conditions are possible in shra tsra. High pressure will build
in Sun with a return toVFR conditions.

Marine
Short term...

while the high pressure overhead will keep locally
generated hazards to a minimum hurricane gert passing off shore
will have an effect on the waters in the form of long period
swell. Waves of around 5ft with a 12 second period are expected
to propagate from gert as it passes 500 miles south east of the
gulf of maine. These waves will impact the more south facing
aspects of the coast from the midcoast through downeast. A high
surf advisory has been issued for the area from tonight through
late Thursday for knox, lincoln, and sagadahoc counties,
including the offshore islands. A small craft advisory for
hazardous seas is also in effect for the adjacent waters during
this time period. Within penobscot bay and waldo county, as well
as further south within casco bay and cumberland county, the
sheltering effect of the islands and bays, combined with the
more east facing aspect will keep surf heights lower.

Long term... As swell from hurricane gert diminishes a persistent
onshore flow will develop in response to a warm front lifting
across the waters. Seas may build above 5 ft again on the outer
waters... Especially by sat. Other than this window... Winds and
seas are expected to remain below SCA thresholds.

Gyx watches warnings advisories
Me... High surf advisory from 8 pm this evening to 8 pm edt Thursday
for mez025>027.

Nh... None.

Marine... Small craft advisory for hazardous seas from 8 pm this evening
to 8 pm edt Thursday for anz150-152.

Synopsis...

near term... Arnott curtis
short term... Curtis
long term... Legro
aviation... Curtis legro
marine... Curtis legro


Weather Reporting Stations
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Stations Dist Age Wind Air TempWater Temp WavesPressureDewPt
BGXN3 - Great Bay Reserve, NH 3 mi98 min NW 1.9 76°F 1014 hPa64°F
IOSN3 - Isle of Shoals, NH 11 mi83 min NW 13 G 14 72°F 1012.6 hPa (+0.7)59°F
44030 - Buoy B0102 - Western Maine Shelf 19 mi79 min E 1.9 G 1.9 70°F 64°F2 ft1013 hPa
WELM1 - 8419317 - Wells, ME 20 mi53 min NNW 12 G 19 76°F 60°F1012.7 hPa
WEXM1 - Wells Reserve, ME 21 mi83 min NW 7 77°F 61°F
44098 - Jeffrey's Ledge, NH (160) 37 mi77 min 67°F3 ft
44029 - Buoy A0102 - Mass. Bay/Stellwagen 40 mi79 min NNW 12 G 14 70°F 67°F1 ft1012.3 hPa
44007 - PORTLAND 12 NM Southeast of Portland,ME 45 mi93 min NW 1.9 G 3.9 67°F 61°F3 ft1012.1 hPa (+0.9)61°F
CASM1 - 8418150 - Portland, ME 49 mi53 min 77°F 60°F1012.4 hPa

Wind History for Wells, ME
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Airport Reports
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AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Pease Air Force Base / Portsmouth, NH3 mi85 minNW 1010.00 miPartly Cloudy78°F59°F53%1012.7 hPa
Rochester - Skyhaven Airport, NH16 mi32 minWNW 1110.00 miFair77°F57°F52%1012.9 hPa
Sanford, Sanford Regional Airport, ME22 mi27 minNNW 810.00 miFair77°F59°F54%1014.1 hPa

Wind History from PSM (wind in knots)
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Last 24hrS9S7SW6SW7S6S6SW5S5SW4SW8SW7SW9SW6W5SW7W6W4W5W6W6NW11NW8NW10NW8
1 day agoW6S4CalmS8S9S6SE5SE6SE5SE5SE3SE3CalmCalmCalmCalmCalmCalmCalmCalmSW3SW4S3W6
2 days agoW9W10W10
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Tide / Current Tables for Atlantic Heights, Piscataqua River, New Hampshire
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Atlantic Heights
Click for Map
Wed -- 12:30 AM EDT     Moonrise
Wed -- 12:31 AM EDT     0.09 feet Low Tide
Wed -- 05:50 AM EDT     Sunrise
Wed -- 06:53 AM EDT     7.40 feet High Tide
Wed -- 12:48 PM EDT     0.41 feet Low Tide
Wed -- 03:18 PM EDT     Moonset
Wed -- 07:17 PM EDT     8.37 feet High Tide
Wed -- 07:43 PM EDT     Sunset
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.
12am1am2am3am4am5am6am7am8am9am10am11am12pm1pm2pm3pm4pm5pm6pm7pm8pm9pm10pm11pm
0.20.212.54.367.17.46.95.63.820.70.412.44.26.27.68.38.17.15.33.2

Tide / Current Tables for Portsmouth Harbor Entrance, New Hampshire Current
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Portsmouth Harbor Entrance
Click for Map
Wed -- 12:30 AM EDT     Moonrise
Wed -- 02:31 AM EDT     0.00 knots Slack
Wed -- 04:25 AM EDT     1.17 knots Max Flood
Wed -- 05:49 AM EDT     Sunrise
Wed -- 07:55 AM EDT     -0.00 knots Slack
Wed -- 10:55 AM EDT     -1.86 knots Max Ebb
Wed -- 02:45 PM EDT     0.00 knots Slack
Wed -- 03:18 PM EDT     Moonset
Wed -- 04:53 PM EDT     1.40 knots Max Flood
Wed -- 07:43 PM EDT     Sunset
Wed -- 08:39 PM EDT     -0.00 knots Slack
Wed -- 11:31 PM EDT     -1.97 knots Max Ebb
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.
12am1am2am3am4am5am6am7am8am9am10am11am12pm1pm2pm3pm4pm5pm6pm7pm8pm9pm10pm11pm
-1.5-1.1-0.40.41.11.10.60.3-0-0.7-1.6-1.9-1.6-1.1-0.60.21.11.41.10.70.3-0.3-1.2-1.9

Weather Map and Satellite Images
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Weather Map
wmap_A
IR Satellite Image from GEOS
east_satellite

GOES Local Image of Northeast    EDIT
Geos

Wind Forecast for Gray/Portland, ME (11,2,3,4)
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Ground Weather Radar Station Portland, ME
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Disclaimer:
The information on this web site has not been checked for accuracy. It is for entertainment purposes only and should be independently verified before using for any other reason. There are five sources. 1) Documents and manuals from a variety of sources. These have not been checked for accuracy and in many cases have not even been read by anyone associated with L-36.com. I have no idea of they are useful or accurate, I leave that to the reader. 2) Articles others have written and submitted. If you have questions on these, please contact the author. 3) Articles that represent my personal opinions. These are intended to promote thought and for entertainment. These are not intended to be fact, they are my opinions. 4) Small programs that generate result presented on a web page. Like any computer program, these may and in some cases do have errors. Almost all of these also make simplifying assumptions so they are not totally accurate even if there are no errors. Please verify all results. 5) Weather information is from numerious of sources and is presented automatically. It is not checked for accuracy either by anyone at L-36.com or by the source which is typically the US Government. See the NOAA web site for their disclaimer. Finally, tide and current data on this site is from 2007 and 2008 data bases, which may contain even older data. Changes in harbors due to building or dredging change tides and currents and for that reason many of the locations presented are no longer supported by newer data bases. For example, there is very little tidal current data in newer data bases so current data is likely wrong to some extent. This data is NOT FOR NAVIGATION. See the XTide disclaimer for details. In addition, tide and current are influenced by storms, river flow, and other factors beyond the ability of any predictive program.