Thursday, April27, 2017 L-36.com


Marine Weather and Tides
Cherry Hill, VA

Version 3.4
What's New / NOTES
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.
3/12/2015 - Added section for Gulf current for users in the GMZ marine zones.
This was requested by a user. If you have requests, please let me know.

Sunrise 6:13AMSunset 7:59PM Thursday April 27, 2017 12:45 PM EDT (16:45 UTC) Moonrise 6:23AMMoonset 8:28PM Illumination 3% Phase: Waxing Crescent; Moon at 2 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
    EDIT      (on/off)   Help
ANZ535 Tidal Potomac From Key Bridge To Indian Head- 1031 Am Edt Thu Apr 27 2017
.small craft advisory in effect through this evening...
Rest of today..S winds 5 kt...increasing to 15 kt with gusts to 20 kt this afternoon. Waves 1 ft.
Tonight..S winds 10 to 15 kt with gusts to 20 kt... Becoming sw 5 kt late. Waves 1 ft. A chance of showers. Patchy fog. Vsby 1 to 3 nm.
Fri..SW winds 5 kt. Waves less than 1 ft.
Fri night..S winds 5 kt. Waves less than 1 ft.
Sat..SW winds 5 to 10 kt. Waves 1 ft. A chance of showers and tstms.
Sat night..W winds around 5 kt. Waves 1 ft. A chance of showers.
Sun..S winds around 5 kt. Waves 1 ft. A chance of showers.
Mon..S winds 5 to 10 kt...becoming sw 10 to 15 kt. Waves 1 to 2 ft. A chance of showers and tstms through the day...then showers and tstms likely through the night. Winds and waves higher and visibilities lower in and near tstms.
ANZ500 1031 Am Edt Thu Apr 27 2017
Synopsis for the tidal potomac and md portion of the chesapeake bay.. A weak cold front will cross the waters tonight. A backdoor cold front will move south across the chesapeake bay region Sunday morning. A stronger cold front will cross the region from the west Monday night. A small craft advisory is possible Monday into Tuesday.

7 Day Forecast for Marine Location Near Cherry Hill, VA
   Hourly   EDIT   Help
location: 38.57, -77.22     debug


Area Discussion for - Baltimore, MD/Washington
      (on/off)   Help   NOTE: mouseover dotted underlined text for definition
Fxus61 klwx 271348
afdlwx
area forecast discussion
national weather service baltimore md/washington dc
948 am edt Thu apr 27 2017

Synopsis
A weak cold front crosses the area from the west tonight. A backdoor
front will slide into the area Saturday evening into Sunday before
lifting north as a warm front early Monday. A stronger cold front
will move through the region from the west Monday night.

Near term /this afternoon/
Atmosphere is in a rather stagnant pattern. Without a wind to
mix out low level moisture has manifested itself as low cloud
and fog. On visible satellite this can be seen to be eroding
along the edges. This will continue during the morning. By
afternoon the Sun should reappear.

Remainder of today will feature warm weather as ridging slides
across the area and moderately strong southerly flow develops.

Southerly wind gusts up to 25 mph by afternoon with highs in the
l/m80s and dewpoints rising into the l/m60s.

Short term /tonight through Saturday night/
Cold front will be approaching the area from the west this evening
and will weaken as it crosses the area. Thunderstorms likely west of
the blue ridge... As time of arrival near or shortly after sunset
will allow some instability to remain. While forecast soundings
suggest instability will be rather limited across this area (due to
relatively poor mid-level lapse rates)... Strong shear could allow
for some organization into convective clusters... Which could briefly
become marginally severe with isolated wind damage. SPC has outlined
this area in a marginal risk because of this.

Any storms will be moving into a progressively hostile environment
as they progress east of the blue ridge... Since instability rapidly
wanes across this area. Thus, expect any storms to rapidly become
elevated and weaken as they approach the metros... With a rather
precipitous decline in lightning activity.

Warm weather continues Friday... With afternoon highs similar (if not
a couple of degrees cooler) to today. Though, cold front will have
shunted best moisture to the south... So dewpoints will be slightly
lower. Warm nose near 800 mb will keep the majority of the area
moderate-to-strongly capped which will suppress convection across
much of the area. One exception could be across across our far
southern counties closer to where better moisture resides... With an
isolated shower/thunderstorm possible. Currently believe any
activity would be just to our south... So left forecast dry for now.

Saturday appears to be the warmest day of the period... With highs
nearing 90f and dewpoints peaking near 70f. This will create
moderate instability by early afternoon (mlcape 1000-2000 j/kg).

Backdoor front may slide into the area during the afternoon... Which
may focus thunderstorm development. Still some uncertainty with
regards to the southward spatiotemporal evolution of front... And
thus whether we would be able to take advantage of the primed
environment. Best chances for thunderstorm activity would reside
along/near front with strong thunderstorms possible given strong
instability and shear (ebs > 40 kts). Any thunderstorms would
become increasingly elevated overnight with a gradual weakening
trend. SPC has introduced a day 3 marginal risk across the northern
half of the forecast area. Spatial location and category look very
good considering aforementioned discussion of parameters and
uncertainty in frontal position.

Long term /Sunday through Wednesday/
The backdoor cold front will be lurking across the forecast
area at the start of the extended forecast period (Sunday).

Present indications are that northeast/north-central maryland
will be most affected. Exact frontal location/movement will be
key, as temperatures north/east of the boundary will be in the
70s (at best), while it'll be approaching 90 south/west of the
front. Confidence improving a little vs. Yesterday, but still
not all that high. Will seek to strike a balance in the
forecast. Will need the warmer air mass to generate enough
instability for thunderstorms.

The front will retreat north Sunday night, but without much fuel for
storms. Mid levels will actually be on the dry side. Surface
dewpoints, on the other hand, will be high for late april. Most
locations will have lows in the 60s.

The forecast area will be in the warm sector before the arrival of a
fairly well-defined cold front Monday night. The pm hours have the
best chance of seeing thunderstorms. It remains to be seen how
strong those storms will be, as temperatures won't fully recover
from the effects wedge, and thus instability values/lapse rates will
be on the lower side.

Behind the front, surface high pressure will reside under zonal
flow. That would support scattered clouds and perhaps a few late-day
sprinkles/showers.

Aviation /14z Thursday through Monday/
With the exception of dca ceilings/vsby have been
oscillating/doing a slow improvement but are still either ifr or
MVFR. This afternoonVFR is expected to return.

A few showers/thunderstorms are possible this evening into the
overnight. The best locations for thunderstorms would be at
kmrb... With less of a chance as activity spreads east of the
blue ridge.

Could be some fog around again tonight... Though confidence is
low.VFR expected Friday.

Shower and thunderstorm chances then return Saturday as frontal
boundary slides into the area. Some strong storms are possible
depending on where the boundary sets up (best chance across
northern half of the area).

The backdoor cold front will be lurking across the terminals on
Sunday, especially in the morning. There is a potential for
flight restrictions with east winds to the north of the front.

Frontal position remains a challenge to forecast. Bwi/mtn stands
a better chance at being impacted than cho though.

The front will return north by Sunday night. There could be some
showers/storms Sunday pm, but confidence and areal coverage both
limited.

A much better defined cold front will arrive from the west Monday
pm. Scattered to numerous thunderstorms appear to be a good bet at
this time, with brief flight restrictions possible within storms.

Marine
Sca begins at noon for all waters. Winds will begin to diminish
overnight. Relatively light winds expected over the waters
Friday into Saturday. Shower and thunderstorms are possible
Saturday afternoon as a front slides into the area... Some storms
could be strong.

The waters will be influenced by a backdoor cold front on
Sunday. Mixing likely will be poor, and the gradient won't be
all that strong either. The front will retreat by Sunday night,
permitting stronger southerly flow on Monday. A better chance at
small craft caliber gusts will develop ahead of a cold front.

But, mixing may not be ideal at the water/air temperature
interface.

Tides/coastal flooding
Tidal anomalies remain elevated across the area. Coastal flood
advisory continues for straits point... As it is currently exceeding
minor flood stage.

Southerly flow today will keep tidal anamolies elevated.

Appears most sites will remain below minor flooding stage for
todays high tide cycle (it is the lower of the two) but will
then threaten minor flooding tonight (especially the sensitive
sites).

Lwx watches/warnings/advisories
Dc... Coastal flood advisory until 1 pm edt this afternoon for
dcz001.

Md... None.

Va... Coastal flood advisory until 1 pm edt this afternoon for
vaz054.

Wv... None.

Marine... Small craft advisory until 5 am edt Friday for anz531>534-537-
539>541-543.

Small craft advisory until midnight edt tonight for anz530-535-
536-538-542.

Update Woody!

Previous Mse/hts


Weather Reporting Stations
   EDIT       (on/off)   Help   NOTE: Click on distance to see the station location on a map
Stations Dist Age Wind Air TempWater Temp WavesPressureDewPt
NCDV2 20 mi45 min S 8 G 11 78°F 64°F1010.1 hPa
WASD2 - 8594900 - Washington, DC 23 mi45 min S 7 G 8.9 72°F 64°F1010.4 hPa
BSLM2 - Chesapeake Bay, MD 31 mi135 min SE 5.1 57°F 1011 hPa53°F
44062 - Gooses Reef, MD 43 mi35 min SSE 9.7 G 12 63°F 1012.1 hPa
SLIM2 - 8577330 - Solomons Island, MD 44 mi45 min NE 1.9 G 4.1 68°F 60°F
COVM2 - 8577018 - Cove Point LNG Pier, MD 46 mi45 min S 9.9 G 11 61°F 1012.1 hPa
TPLM2 - Thomas Point, MD 47 mi45 min S 1.9 G 2.9 63°F 58°F
PPTM2 - 8578240 - Piney Point, MD 47 mi45 min SW 6 G 8
44063 - Annapolis 49 mi35 min S 3.9 G 5.8 63°F 1011.4 hPa
APAM2 - 8575512 - Annapolis, MD 49 mi45 min 69°F 1011 hPa

Wind History for Washington, DC
(wind in knots)    EDIT      (on/off)   Help
1
PM
2
PM
3
PM
4
PM
5
PM
6
PM
-12
PM
8
PM
-12
PM
10
PM
11
PM
12
AM
1
AM
2
AM
3
AM
4
AM
5
AM
6
AM
7
AM
8
AM
9
AM
10
AM
11
AM
12
PM
Last
24hr
NW6
NW3
G7
NW4
N3
G6
--
SE6
SE3
SE2
SE1
G4
S3
--
E1
E1
--
E1
--
E1
E1
S3
S1
S4
S7
1 day
ago
NE5
G12
NE5
G9
NE3
G10
E3
G13
NE4
G7
NE6
G11
NE1
G7
NE2
G10
NE4
G11
N4
G10
N3
G8
N4
N4
N3
N4
G11
N3
G6
N6
N8
N4
G11
NW5
G8
NW5
G8
NW6
G9
NW5
G8
NW6
G9
2 days
ago
NE4
G10
NE1
G7
NE3
G7
N3
G7
NE2
G7
N2
G8
N1
G4
NE2
G9
NE3
G12
N4
G9
NE3
G6
NE3
G8
NE1
G5
NE2
G6
NE4
G10
NE2
G8
NE4
G10
NE2
G8
NE4
G9
NE3
G11
NE4
G15
NE8
G16
N6
G11

Airport Reports
    EDIT      (on/off)   Help   Click EDIT to display multiple airports
AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Quantico Marine Corps Airfield - Turner Field, VA6 mi50 minS 410.00 miMostly Cloudy72°F64°F79%1010.9 hPa
Fort Belvoir, VA11 mi48 minSSE 510.00 miA Few Clouds75°F63°F68%1011.1 hPa
Stafford, Stafford Regional Airport, VA17 mi51 minSSW 610.00 miFair76°F64°F67%1011.8 hPa
Manassas, Manassas Regional Airport/Harry P. Davis Field, VA19 mi50 minN 010.00 mi72°F64°F79%1011.7 hPa
Washington/Reagan National Airport, DC, VA22 mi54 minS 610.00 miOvercast75°F66°F74%1011 hPa
Fredericksburg, Shannon Airport, VA24 mi51 minS 5 G 810.00 miFair79°F65°F63%1010.5 hPa

Wind History from NYG (wind in knots)
1
PM
2
PM
3
PM
4
PM
5
PM
6
PM
7
PM
8
PM
9
PM
10
PM
11
PM
12
AM
1
AM
2
AM
3
AM
4
AM
5
AM
6
AM
7
AM
8
AM
9
AM
10
AM
11
AM
12
PM
Last 24hrE6E8E5E6CalmE5NE5SE4S7S7S5SE5SE4SE3CalmSE3CalmNW3E3E3------S4
1 day agoNE20
G27
NE15
G23
NE16NE14NE16NE13NE9NE8NE6N8N8N7N5N7N8N8N10N8NW7N7N9N7NE7N4
2 days agoNE8NE12NE12--N10NE7NE14
G19
NE14
G22
NE10
G18
NE13NE13
G21
NE15
G19
NE15NE11NE16
G22
NE15
G22
NE14NE15
G22
NE16NE19
G26
NE18
G25
NE17
G27
NE18
G27
NE22
G32

Tide / Current Tables for Deep Point, Mattawoman Creek, Potomac River, Maryland
   EDIT   RT Ports Option   Weekend mode (on/off)   (on/off)   Help   One Week of Data
Deep Point
Click for Map
Thu -- 02:18 AM EDT     0.08 feet Low Tide
Thu -- 06:16 AM EDT     Sunrise
Thu -- 07:23 AM EDT     Moonrise
Thu -- 08:01 AM EDT     2.15 feet High Tide
Thu -- 03:10 PM EDT     -0.02 feet Low Tide
Thu -- 07:57 PM EDT     Sunset
Thu -- 08:39 PM EDT     1.86 feet High Tide
Thu -- 09:28 PM EDT     Moonset
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.
12am1am2am3am4am5am6am7am8am9am10am11am12pm1pm2pm3pm4pm5pm6pm7pm8pm9pm10pm11pm
0.50.20.10.10.511.622.121.61.20.80.40.1-00.10.51.11.61.81.81.61.2

Tide / Current Tables for Glymont, Potomac River, Maryland
   EDIT      (on/off)   Help   One Week of Data
Glymont
Click for Map
Thu -- 02:43 AM EDT     0.09 feet Low Tide
Thu -- 06:15 AM EDT     Sunrise
Thu -- 07:23 AM EDT     Moonrise
Thu -- 08:26 AM EDT     2.41 feet High Tide
Thu -- 03:35 PM EDT     -0.02 feet Low Tide
Thu -- 07:57 PM EDT     Sunset
Thu -- 09:04 PM EDT     2.09 feet High Tide
Thu -- 09:28 PM EDT     Moonset
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.
12am1am2am3am4am5am6am7am8am9am10am11am12pm1pm2pm3pm4pm5pm6pm7pm8pm9pm10pm11pm
0.70.40.10.10.30.91.62.12.42.421.51.10.60.3000.30.91.51.92.11.91.6

Weather Map and Satellite Images
       (on/off)   Help
Weather Map
wmap_A
IR Satellite Image from GEOS
east_satellite

GOES Local Image of Mid-Atlantic    EDIT
Geos

Wind Forecast for Baltimore, MD/Washington (12,3,4,5)
      (on/off)   Help

Ground Weather Radar Station Sterling, VA
   (on/off)   Help
weather_mapweather_map weather_map

Ad by Google

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.