Tuesday, November21, 2017 L-36.com


Marine Weather and Tides
Betterton, MD

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 6:55AMSunset 4:47PM Tuesday November 21, 2017 2:35 PM EST (19:35 UTC) Moonrise 9:26AMMoonset 7:25PM Illumination 10% Phase: Waxing Crescent; Moon at 3 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
ANZ530 Chesapeake Bay North Of Pooles Island- 1231 Pm Est Tue Nov 21 2017
.small craft advisory in effect until midnight est tonight...
.small craft advisory in effect from Wednesday morning through Wednesday afternoon...
This afternoon..S winds 15 kt with gusts to 20 kt. Waves 2 ft.
Tonight..SW winds 5 to 10 kt. Gusts up to 20 kt until early morning. Waves 1 ft. A chance of showers.
Wed..NW winds 10 to 15 kt. Gusts up to 20 kt. Waves 1 to 2 ft.
Wed night..NW winds 5 to 10 kt. Waves 1 ft.
Thu..W winds 5 kt. Waves flat.
Thu night..W winds 5 kt. Waves flat.
Fri..SW winds 5 to 10 kt. Waves 1 ft or less.
Sat..W winds 5 to 10 kt. Waves 1 ft.
ANZ500 1231 Pm Est Tue Nov 21 2017
Synopsis for the tidal potomac and md portion of the chesapeake bay.. High pressure will move offshore through this afternoon. A cold front will pass through late tonight into early Wednesday morning. High pressure will return later Wednesday through early Friday, then another cold front will approach late Friday into Saturday. A small craft advisory will likely be needed for portions of the waters Wednesday night, and again Friday night through Saturday.

7 Day Forecast for Marine Location Near Betterton, MD
   Hourly   EDIT   Help
location: 39.37, -76.04     debug


Area Discussion for - Philadelphia/Mount Holly, PA
      (on/off)   Help   NOTE: mouseover dotted underlined text for definition
Fxus61 kphi 211436
afdphi
area forecast discussion
national weather service mount holly nj
936 am est Tue nov 21 2017

Synopsis
A cold front will cross the area Tuesday night and early Wednesday,
followed by high pressure into Saturday. Another cold front is
expected to cross the area Saturday night, with high pressure
anticipated for the first part of next week.

Near term until 6 pm this evening
Morning forecast mainly on track. Will adjust hourly grids based
on latest surface obs and satellite trends, but no significant
changes.

Otherwise, digging vort MAX in the upper midwest will continue
southeastward through the great lakes region today. Downstream,
midlevel ridging will amplify in response to low-level warm-air
advection expanding the atmospheric column. Predecessor
perturbations in the flow will progress through the east today,
though these should have generally minimal impacts on sensible
weather other than increasing high clouds, especially this
afternoon. As the surface ridge to our south continues offshore
today, southwesterly flow will continue, getting a boost from
diabatic heating and a strong surface low moving through ontario
(aiding in an increased surface pressure gradient). As such,
expect breezy conditions again today, especially along southeast
of the urban corridor, as areas to the northwest will be in
somewhat of a surface col by afternoon.

Statistical guidance shows good agreement, but I suspect there
is a bit of a cool bias with temperatures today given the
warming profiles and the amplified ridging. Hard to go against
good agreement among the guidance, but I did nudge up
temperatures a degree or two in spots from the inherited
forecast. It is quite possible that philly reaches 60 today,
with overall MAX temperatures about 2-7 degrees above seasonal
averages.

Short term 6 pm this evening through 6 am Wednesday
A perturbation over the southeast will lift northeastward
during the day, likely in vicinity of the carolinas by 21z.

Precipitation should break out near this vort max, with a
surface wave likely developing during the day near or off the
coast of florida. This southern-stream system will be affected
strongly by the northern-stream vort max, with some phasing
likely to occur during the overnight period, and rapid
development northeastward progression of the surface low
near off the carolina coast. However, despite the overall
excellent agreement in the large-scale pattern, the NAM gfs
depictions of the southern-stream low leave some question marks.

The GFS looks a little on the fast progressive side, which is a
typical bias it exhibits in the short term. Comparison to the
rgem suggests it might be on the order of 3 hours too fast, and
this difference may be enough to keep the GFS too dry tonight.

It will be critical to watch the evolution of the southern-
stream system today (and the precipitation upscale feedback
processes) to determine if the GFS is keeping us too dry
tonight.

Meanwhile, the NAM looks very similar to the rgem in the
overall evolution of the system tonight, but the NAM is simply
drier than the rgem (another bias observed on multiple occasions
this season). Based on this (and the GFS bias), I weighted
guidance that was slightly slower wetter (e.G., the NAM nest and
the wrf- arw, along with the rgem) somewhat higher. Also
included some of the 00z ECMWF with the QPF grids tonight,
despite its coarser resolution, as it seems to be doing a good
job this fall depicting the cutoff of the poleward side of the
precipitation somewhat better than the nam GFS (likely because
of its general slower deeper depictions of these phasing
systems).

The northern-stream upper-level jet streak will be in a favorable
position by night's end for rather deep ascent, but by this point,
the stronger lift will probably be offshore. Nevertheless, mesoscale
banding of the precipitation is clearly evident in most of the model
simulations tonight, and this does occur as far west as i-95 in most
of these simulations. This makes the QPF a challenge, since these
setups can be underdone in the models (both with precipitation rates
and the slow progression of these phenomena compared to the speed of
deep-layer flow). This was another reason I upped the QPF from the
previous forecast, but tempered to some degree versus the wettest
guidance (sref ecmwf).

With the above in mind, brought pops up to chance generally urban
corridor southeastward and to likely southeast of a dover, de, to
sandy hook, nj, line. The timing of the precipitation looks to be
mainly after midnight, but there is some uncertainty here given the
discrepancies mentioned earlier. Amounts generally in the tenth to
quarter inch range along southeast of i-95 to potentially a half
inch near the coast, but confidence in these values is low because
of the uncertainty with the exact track of the precipitation. Also,
the cutoff of the precipitation will likely be sharper than I have
depicted in the grids (an inevitable result of precipitation
forecast uncertainty). Bottom line: large errors in the pops QPF are
possible tonight given the remaining model discrepancies.

Temperatures were generally a blend of met mav ecs mos, though I did
nudge temperatures up a little, in general given the increased
clouds and remaining low-level south southwest fetch. Looks like
temperatures will be too warm for non-liquid, non-freezing
precipitation anywhere in our CWA through daybreak.

One final note: given the strengthening dynamics aloft, strong lift
will aid in midlevel cooling possibly enough to generate some
marginal instability. Not totally out of the question to see a
couple lightning strikes, though the best chances are offshore.

Long term Wednesday through Monday
The extended period starts off with a cold front near or along the
coast Wednesday morning, moving east. Chillier air, normal for this
time of year, will move in behind this front. With ridging aloft
over the western u.S. And troughiness in the east, a seasonably cool
but mostly dry pattern is expected through most of the long term
period, with a chance of precipitation later Saturday and Sunday as
another cold front and associate deep upper level trough crosses the
mid-atlantic region.

The FROPA early Wednesday will trigger a few showers N W of phl. A
sfc low pressure is also forecast to develop off the nc sc coasts
with moisture spreading north ahead of it along the de nj coastal
areas. The highest pops continue over southern nj and delmarva,
counter to climo. Overnight temps should remain warm enough so that
all precip will be in liquid form. However a few showers may linger
past sunrise, and with cold advection behind the front a few snow
showers or flurries are possible in the poconos Wednesday morning.

The weather for Wed afternoon through Friday night will be dominated
by high pressure moving across the mid-atlantic region. Temperatures
will be a few degrees below normal on Thursday but should return to
near normal by Friday as the high shifts offshore and a more swly
flow develops. A cold front may push south in to ny state and new
england on Friday but probably will not affect our area to the south,
another fast-moving frontal system is forecast to push through our
area on Saturday. In part because of its fast movement it will not
be able to pick up much moisture. The current forecast continues
chance pops, higher N W of phl, but even this may be overdone.

Again, temps on Saturday appear to be warm enough to avoid any
frozen precip. However, the airmass behind this front seems to be
colder than the one mid-week, with strong low level cold advection
beginning Saturday night and continuing through the rest of the
weekend. This pattern of NW flow will favor lake effect snow with
some streamers possibly reaching the poconos and vicinity.

Aviation 15z Tuesday through Saturday
The following discussion is for kphl, kpne, kttn, kabe, krdg, kilg,
kmiv, kacy and surrounding areas.

Today...VFR with southwest winds 5 to 15 kts with occasional
gusts to 20 kts or so, especially from the i-95 corridor
southeastward. High confidence.

Tonight... Rapidly increasing clouds, possibly to sub-vfr,
especially closer to the coast. Showers should spread from
southwest to northeast through the area after 06z Wednesday,
mainly confined to the urban corridor southeastward. For now,
confidence only high enough for mention in the miv acy tafs as a
prevailing condition. Sub-vfr vsbys CIGS are possible with the
heavier showers, but confidence on timing and how far inland the
precipitation reaches is very low, so kept tafs generallyVFR
through the period for now. Winds generally southwest around or
below 10 kts, with some veering to westerly expected by
daybreak. Medium confidence with winds; low confidence with
cigs vsbys.

Outlook...

Wednesday... Rain possible south and east of i-95 early Wednesday
morning with MVFR or lower conditions... Then becomingVFR. Sw
winds 5-10 kt become NW Wednesday afternoon and increase to
10-20 kt.

Wednesday night and Thursday...VFR. NW winds gradually diminishing.

A storm system is currently expected to remain offshore. Forecast
confidence: medium to high.

Friday...VFR. NW winds 5-10 kt.

Saturday and Saturday night...VFR early... Then MVFR or lower
conditions possible in rain showers later in the day and at night.

Sw winds 10-15 kt.

Marine
Small craft advisory in effect for delaware bay and the
delaware atlantic coastal waters through today and for the new
jersey coastal waters through this evening as strong southwest
winds continue increase today. Winds should diminish overnight,
especially over delaware bay and the adjacent atlantic waters,
though confidence is not particularly high given the potentially
brief duration of these lighter winds.

Showers should spread northeastward overnight (generally after
midnight), with localized restrictions possible. Expect erratic
gusts and locally very choppy seas in vicinity to showers. A
lightning strike or two is not out of the question, though the
probability is too low for inclusion in the forecast at this
point.

Outlook...

Wednesday... Lull in SCA conditions possible Wednesday morning.

Otherwise, winds shift to the NW and increase to 15-20 kt with 25-30
kt gusts.

Thursday through Friday... Sub-sca conditions expected.

Saturday and Sunday... SCA conditions are possible with the passage
of a strong cold front.

Phi watches warnings advisories
Pa... None.

Nj... None.

De... None.

Md... None.

Marine... Small craft advisory until 4 am est Wednesday for anz450>453.

Small craft advisory until 10 pm est this evening for anz454-
455.

Small craft advisory until 7 pm est this evening for anz430-
431.

Synopsis... Miketta
near term... Cms mps
short term... Cms
long term... Miketta
aviation... Cms miketta mps
marine... Cms miketta mps


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
44057 - Susquehanna, MD 12 mi45 min SSW 3.9 G 5.8 53°F 1017.4 hPa
TCBM2 - 8573364 - Tolchester Beach, MD 15 mi47 min S 9.9 G 14 56°F 49°F1017.3 hPa
CHCM2 - 8573927 - Chesapeake City, MD 16 mi53 min SSE 9.9 G 16 59°F 47°F1017.6 hPa
44043 - Patapsco, MD 24 mi45 min S 12 G 16 54°F 1018.1 hPa
RDYD1 - 8551910 - Reedy Point, DE 28 mi47 min 62°F 47°F1016.8 hPa
FSKM2 - 8574728 - Francis Scott Key Bridge, MD 28 mi47 min SSW 13 G 18 59°F 1016.6 hPa
DELD1 - 8551762 - Delaware City, DE 28 mi47 min SW 4.1 G 12 61°F 45°F1017.2 hPa
BLTM2 - 8574680 - Baltimore, MD 29 mi47 min W 8.9 G 15 60°F 55°F1016.2 hPa
CPVM2 32 mi47 min 55°F 44°F
44063 - Annapolis 35 mi45 min S 14 G 19 58°F 1016.5 hPa
SJSN4 - 8537121 - Ship John Shoal, NJ 35 mi47 min S 13 G 19 55°F 51°F1017.5 hPa
APAM2 - 8575512 - Annapolis, MD 35 mi47 min 59°F 1016.8 hPa
DRSD1 - Delaware Reserve, DE 37 mi65 min SSW 9.9 61°F 1018 hPa33°F
TPLM2 - Thomas Point, MD 39 mi35 min SSW 16 G 18 56°F 52°F
MRCP1 - 8540433 - Marcus Hook, PA 45 mi53 min 55°F 53°F1017 hPa

Wind History for Tolchester Beach, MD
(wind in knots)    EDIT      (on/off)   Help
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
1
PM
2
PM
Last
24hr
W13
G16
W12
W12
SW12
G16
SW14
SW9
G14
S8
G11
S9
S4
G11
S9
G12
S7
G12
S10
S7
G10
S8
G13
S11
S9
G15
S9
G14
S11
G15
SW12
G17
SW13
G17
SW14
G17
S8
G11
S14
G21
S8
G15
1 day
ago
NW26
G32
W24
G29
NW22
NW19
G26
NW18
G25
NW13
G16
W11
G14
W16
NW18
G22
NW17
G23
NW14
G20
NW19
G26
NW15
G19
NW20
G27
NW18
G25
NW17
W14
G17
W16
NW8
G14
NW7
W13
W14
G17
W14
G18
W13
2 days
ago
S9
G15
S7
G14
S9
G15
S7
G14
S11
G21
S7
G17
S11
G17
S13
G24
S12
G19
S12
G22
S10
G17
S9
G14
S10
G16
S14
G23
W17
W30
NW29
G38
W23
G29
NW22
G28
NW27
NW25
G31
NW22
G30
W23
G28
NW25
G31

Airport Reports
    EDIT      (on/off)   Help   Click EDIT to display multiple airports
AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Phillips Army Air Field / Aberdeen, MD10 mi97 minSSW 1110.00 miMostly Cloudy56°F31°F39%1018.6 hPa
Baltimore / Martin, MD20 mi50 minN 010.00 miMostly Cloudy59°F37°F45%1017.6 hPa

Wind History from APG (wind in knots)
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
1
PM
2
PM
Last 24hrW13
G19
W9SW5SW4W4CalmCalmCalmCalmCalmW3W6SW7SW7CalmSW7SW7SW10SW12SW16
G19
SW10
G20
SW11SW11SW12
G17
1 day agoNW15
G25
NW8
G17
W9
G18
W15
G21
W13
G17
W9W6W4W7W8W8W9W8W6W7W7SW4NW8W13
G20
W13
G17
W9
G16
W7W7W12
2 days agoS8S9S8S7S10SW9S16
G22
S17
G25
SW19
G27
SW16
G23
SW14SW11S16
G22
SW18
G23
SW9W18
G30
W18
G25
W17
G25
W15
G21
W17
G30
NW13
G27
W12
G22
W12
G26
NW15
G22

Tide / Current Tables for Betterton, Maryland
   EDIT   RT Ports Option   Weekend mode (on/off)   (on/off)   Help   One Week of Data
Betterton
Click for Map
Tue -- 05:30 AM EST     0.45 feet Low Tide
Tue -- 06:54 AM EST     Sunrise
Tue -- 09:25 AM EST     Moonrise
Tue -- 10:31 AM EST     1.33 feet High Tide
Tue -- 04:05 PM EST     0.03 feet Low Tide
Tue -- 04:45 PM EST     Sunset
Tue -- 07:25 PM EST     Moonset
Tue -- 11:10 PM EST     2.18 feet High Tide
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.
12am1am2am3am4am5am6am7am8am9am10am11am12pm1pm2pm3pm4pm5pm6pm7pm8pm9pm10pm11pm
21.71.30.90.70.50.50.60.91.11.31.31.10.80.40.100.10.40.81.21.722.2

Tide / Current Tables for Chesapeake and Delaware Canal, Maryland/Delaware Current
   EDIT      (on/off)   Help   One Week of Data
Chesapeake and Delaware Canal
Click for Map
Tue -- 02:21 AM EST     -1.55 knots Max Ebb
Tue -- 05:14 AM EST     0.04 knots Slack
Tue -- 06:54 AM EST     Sunrise
Tue -- 08:34 AM EST     1.84 knots Max Flood
Tue -- 09:24 AM EST     Moonrise
Tue -- 10:49 AM EST     -0.01 knots Slack
Tue -- 02:25 PM EST     -2.20 knots Max Ebb
Tue -- 04:43 PM EST     Sunset
Tue -- 06:07 PM EST     0.07 knots Slack
Tue -- 07:24 PM EST     Moonset
Tue -- 09:17 PM EST     2.18 knots Max Flood
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.
12am1am2am3am4am5am6am7am8am9am10am11am12pm1pm2pm3pm4pm5pm6pm7pm8pm9pm10pm11pm
-0.1-1.2-1.5-1.5-1.1-0.50.81.41.81.81.3-0.6-1.5-1.9-2.2-2.2-1.8-1.3-0.41.21.92.22.11.6

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 Philadelphia/Mount Holly, PA (14,3,4,5)
      (on/off)   Help

Ground Weather Radar Station Dover AFB, DE
   (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.