Wednesday, February20, 2019 L-36.com


Marine Weather and Tides
Portsmouth, NH

Version 3.4
What's New / NOTES
10/6/2018 Colors of tide XTide graphs changed to emphasize that they were upgraded. See next note. Comments welcome.
10/4/2018 I have fixed XTide and updated the harmonic files. There were some name changes so you might have to click EDIT to find the new station name.

Sunrise 6:31AMSunset 5:21PM Wednesday February 20, 2019 12:25 PM EST (17:25 UTC) Moonrise 7:47PMMoonset 8:25AM Illumination 98% Phase: Waning Gibbous; Moon at 16 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- 1107 Am Est Wed Feb 20 2019
This afternoon..W winds 5 to 10 kt. Seas 1 foot or less.
Tonight..S winds around 10 kt, becoming se with gusts up to 25 kt after midnight. Seas 1 to 2 ft, building to 2 to 4 ft after midnight. A chance of snow in the evening, then snow and rain after midnight. Vsby 1 to 3 nm, decreasing to variable to less than one quarter nm after midnight.
Thu..SE winds 5 to 15 kt, becoming W 10 to 15 kt in the afternoon. Seas 3 to 5 ft. Rain likely in the morning with vsby 1 to 3 nm.
Thu night..W winds 15 to 20 kt, becoming nw 10 to 20 kt after midnight. Gusts up to 30 kt. Seas 3 to 5 ft.
Fri..NW winds 10 to 15 kt with gusts up to 25 kt. Seas 2 to 3 ft in the morning, then 1 foot or less.
Fri night..NW winds 10 to 15 kt, becoming N 5 to 10 kt after midnight. Seas 2 to 3 ft in the evening, then 1 foot or less.
Sat..W winds 5 to 10 kt. Seas around 2 ft.
Sat night..S winds 10 to 15 kt with gusts up to 25 kt. Seas 2 to 4 ft. Rain with a chance of snow.
Sun..SE winds 10 to 20 kt with gusts up to 30 kt. Seas 4 to 6 ft. Rain.
Sun night..SW winds 15 to 25 kt with gusts up to 30 kt. Seas 5 to 8 ft. A chance of rain.
ANZ100 1107 Am Est Wed Feb 20 2019
Synopsis for stonington me to merrimack river ma out to 25 nm.. Low pressure crosses the waters tonight and Thursday with southerly winds shifting to west behind the front. High pressure builds out of the great lakes again behind the front, cresting over the gulf of maine on Saturday. Low pressure than moves along the maine coast on Sunday. &&


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 201615
afdgyx
area forecast discussion
national weather service gray me
1115 am est Wed feb 20 2019

Synopsis
As high pressure moves off to the east today the next frontal
system will approach from the west. While the main area of low
pressure tracks through the great lakes and into canada, a warm
front will lift northeast across new england tonight into early
Thursday, providing the focus for snowfall before the
temperature warms up behind the warm front. A cold front will
drop in from the north Thursday evening bringing cooler weather
back into the region. High pressure moves in from the west
Friday and exits to the east on Saturday. Meanwhile the next
storm system will be developing in the southern plains and
tracking northeast toward the great lakes. It will bring
another frontal system into new england Saturday night into
Sunday bringing another round of wintry precipitation.

Near term until 6 pm this evening
1100 am update...

sunshine is fading behind high clouds late this morning as high
pressure shifts offshore. Looking for clouds to gradually lower
and thicken this afternoon and into the evening as the next
storm system approaches from the southwest. Have adjusted
temps tds based on current obs but no major changes to current
forecast planned attm.

Prev disc...

635 am... Just made a few tweaks to the forecast based on the
highly variable temps early this am, tapering the decoupled
spots as they won't warm up as fast, given the light flow over
the next few hours. Otherwise forecast in good shape with only
increasing clouds expected this afternoon.

Previously... Sfc high begins to push east of the CWA later
today, but today will remain dry, with increasing clouds from
sw-ne in the afternoon. Highs will be a few degrees warmer than
Tuesday, generally ranging from the low to mid 20s in the N to
around in SRN nh and on the coast.

Short term 6 pm this evening through 6 pm Thursday
Our next unphased system arrives tonight. As SRN stream system,
which really looks more like the dampening of a wave at 500 mb
scoots out ahead of the NRN better SRN stream wave. Still that
srn wave interacting with the NRN system does produce some
decent mid lvl thermal forcing, and that will bring a period of
precip, which should be mainly snow in all but SRN nh, where a
period of fzra and maybe even just plain rain is possible as it
winds down around or shortly after daybreak. Along the me coast
could see a brief period of fzra or rain early Thu morning,
before it ends as well, but it will be mainly sn for most inland
areas and overall 3-6" looks reasonable, with the highest in
the western me mtns. In SRN nh the mixing will keep amts closer
to 1-3", with 2-4" expected on the me coast. Thinking is that it
will likely hold off until after 00z in SRN nh, so the evening
commute should be ok, but once again, the Thu morn commute could
be tricky. The good new for most of the areas, outside the mtns
is that precip should end by midday, and there will be some sun
by afternoon, with highs reaching above freezing, and into the
mid 30s to low 40s.

Long term Thursday night through Tuesday
As low pressure shifts east a cold front will drop in from the
north behind it Thursday night, shifting winds to the north and
dropping the temperature back below freezing. Northwest winds on
Friday will bring downslope mixing over the coastal plain
allowing the temperature to reach the upper 30s to low 40s
again despite the frontal passage. High pressure slides across
the region Friday night providing our most ideal night for
radiational cooling. The air mass is not all that frigid or dry,
so the floor for temperatures looks like the low teens for the
cold spots, perhaps a few single digit readings. We will warm
back up into the upper 30s to low 40s again on Saturday.

The next precipitation maker for our area will take shape over
the texas panhandle Saturday morning before tracking northeast
toward the great lakes... A familiar track for storms this
season. This once again places new england on the warm side of
the system with warm advection precipitation arriving Saturday
night and Sunday. This time the warm front moves in from the
south, which sets up a better easterly low level flow ahead of
it. This is a cold air damming flow and thus expect cold air to
hold on tough for a broader area, at least at the ground level.

Meanwhile the warm advection aloft will cause precipitation to
change from snow to freezing rain from south to north on Sunday.

Far southern new hampshire and coastal maine could break into
some warmer air and end the freezing rain earlier, but interior
western maine and central new hampshire will likely stay in the
cold air most of the day with a longer duration of freezing
rain. There is still some uncertainty on how far north the warm
air aloft moves. A secondary low forming off the southern new
england coastline could help to hold in deeper cold air and
allow for more snowfall, but without this holding the warm air
back we will likely see the switch to freezing rain all the way
north to the western maine mountains.

The front shifts east Sunday evening, shutting off the steady
precipitation. As winds go to the west, those areas which held
on to the cold air damming will see the temperature finally warm
up briefly before cold advection brings it back down to freezing
Monday morning. Some lingering snow showers are likely in the
mountains through Monday with a northwest flow bringing upslope
enhancement there and downslope mixing on the coastal plain.

The next wave arrives in our area Tuesday night into Wednesday,
a week from now. At this point models can't decide whether this
will track to our north or to our south, but another round of
light snow is possible.

Aviation 16z Wednesday through Sunday
Short term... Expect ifr of lower tonight into Thu morning in sn
and low cigs. Some fzra possible late tonight and early Thu at
kmht kpsm kcon, and maybe kpwm. Improvement toVFR expected thu
afternoon at all but khie.

Long term... Lingering MVFR ceilings in the mountains Thursday
night but becomingVFR elsewhere all the way through Saturday.

The next storm system arrives Saturday night into Sunday with
widespread ifr conditions and snow changing to freezing rain for
most of the area.

Marine
Short term... 0630 update... Just dropped the fz spray adv. It's
pretty cold this morning, but with lightening winds and
warming, any light fz spray will diminish over the next few
hours.

May see SCA winds briefly late tonight into early
thu, in SE flow, but the better chc for SCA winds in NW flow
late Thu and into Thu night.

Long term... Winds shift to the northwest behind a cold front
Thursday evening and they could gust to 25 kt or so for a bit.

Winds gradually diminish through Friday as high pressure arrives
from the west. The next frontal system arrives on Sunday with a
southeast flow ahead of it likely to reach small craft advisory
levels once again.

Tides coastal flooding
Storm surge of around a half foot will combine with high
astronomical tides on Thursday to produce minor coastal flooding
and splash-over at the time of high tide which occurs around
noon.

Gyx watches warnings advisories
Me... Winter weather advisory from 11 pm this evening to noon est
Thursday for mez007>009-012>014-018>028.

Nh... Winter weather advisory from 8 pm this evening to 10 am est
Thursday for nhz001>015.

Marine... None.



Weather Reporting Stations
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Stations Dist Age Wind Air TempWater Temp WavesPressureDewPt
BGXN3 - Great Bay Reserve, NH 3 mi101 min W 2.9 24°F 1035 hPa4°F
IOSN3 - Isle of Shoals, NH 11 mi86 min NW 4.1 G 5.1 22°F 1034.5 hPa (-0.8)3°F
44030 - Buoy B0102 - Western Maine Shelf 19 mi82 min NW 1.9 G 1.9 24°F 38°F1 ft1034.4 hPa
WELM1 - 8419317 - Wells, ME 20 mi38 min SE 1.9 G 2.9 25°F 36°F1034 hPa
WEXM1 - Wells Reserve, ME 21 mi86 min NNW 2.9 24°F -0°F
44098 - Jeffrey's Ledge, NH (160) 37 mi48 min 40°F2 ft
44029 - Buoy A0102 - Mass. Bay/Stellwagen 40 mi82 min NNW 3.9 G 5.8 24°F 37°F1 ft1034.4 hPa
44007 - PORTLAND 12 NM Southeast of Portland,ME 45 mi36 min Calm G 1.9 23°F 36°F1 ft1033.8 hPa (-1.8)10°F
CASM1 - 8418150 - Portland, ME 49 mi44 min 24°F 35°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 mi30 minW 310.00 miOvercast25°F2°F38%1033.9 hPa
Rochester - Skyhaven Airport, NH16 mi35 minN 010.00 miFair25°F3°F40%1033.3 hPa
Sanford, Sanford Regional Airport, ME22 mi30 minN 010.00 miFair32°F7°F35%1034.2 hPa

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W9NW6NW4CalmN3W4W8W9W7W6W4W4W4W6W6W6W5N4W3
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Tide / Current Tables for Atlantic Heights, Piscataqua River, New Hampshire
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Atlantic Heights
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Wed -- 05:30 AM EST     -1.04 feet Low Tide
Wed -- 06:33 AM EST     Sunrise
Wed -- 07:25 AM EST     Moonset
Wed -- 11:55 AM EST     9.54 feet High Tide
Wed -- 05:20 PM EST     Sunset
Wed -- 06:06 PM EST     -1.65 feet Low Tide
Wed -- 06:46 PM EST     Moonrise
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.

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8.57.45.42.80.5-0.9-0.90.32.457.499.58.86.94.11.3-0.8-1.6-1.20.52.95.57.6

Tide / Current Tables for Portsmouth Harbor Entrance, New Hampshire Current
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Portsmouth Harbor Entrance
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Wed -- 12:48 AM EST     -0.00 knots Slack
Wed -- 03:34 AM EST     -2.29 knots Max Ebb
Wed -- 06:33 AM EST     Sunrise
Wed -- 07:12 AM EST     0.00 knots Slack
Wed -- 07:25 AM EST     Moonset
Wed -- 09:27 AM EST     1.81 knots Max Flood
Wed -- 01:05 PM EST     -0.00 knots Slack
Wed -- 04:01 PM EST     -2.61 knots Max Ebb
Wed -- 05:20 PM EST     Sunset
Wed -- 06:46 PM EST     Moonrise
Wed -- 07:47 PM EST     0.00 knots Slack
Wed -- 09:59 PM EST     1.76 knots Max Flood
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.

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0.7-0.2-1.4-2.2-2.2-1.9-1.3-0.311.71.71.30.90.1-1.1-2.2-2.6-2.4-1.9-10.31.41.81.5

Weather Map and Satellite Images
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GOES Local Image of    EDIT
NOTE: East coast views moved to GEOS-16. They are experimental and not well supported by NOAA so they may not be correct so be warned. This change required redoing a large amount of the GOES code. If the image you are expecting is not showing, please let me know. You may need to use the EDIT function to update your location.
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Wind Forecast for Gray/Portland, ME (12,3,4,5)
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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.