Friday, December15, 2017 L-36.com


Marine Weather and Tides
Pelican Bay, TX

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 7:23AMSunset 5:26PM Friday December 15, 2017 5:42 PM CST (23:42 UTC) Moonrise 4:57AMMoonset 4:00PM Illumination 6% Phase: Waning Crescent; Moon at 27 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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7 Day Forecast for Marine Location Near Pelican Bay, TX
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location: 32.91, -97.5     debug


Area Discussion for - Fort Worth, TX
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Fxus64 kfwd 152205
afdfwd
area forecast discussion
national weather service fort worth tx
405 pm cst Fri dec 15 2017

Short term
Other than a few high clouds across the region this afternoon,
mostly clear skies are in control over much of the state. Surface
high pressure is in control over the gulf coast of texas, while a
lee trough is beginning to strengthen over the panhandle and west
texas. Tonight will remain quite dry, allowing for temperatures
to drop into the upper 30s in the urban areas and east, while
dropping to near freezing in the west.

Fox

Long term
The upper level low in the baja region will eject northeastward
during the day tomorrow and bring a rapid change in our sensible
weather. The morning will start out mostly clear but cloud cover
will quickly over spread the region from the south as low and mid
level moisture surges northward. The increasing clouds moisture
and cool temperatures in the 50s to low 60s should inhibit a
critical wildfire threat from developing, but elevated fire danger
still warrants caution. Isentropic lift will be very strong and
should result in a large swath of rain that develops after midday
and encompasses most of the region by sunset. Pops will be high
due to good confidence in measurable rain, but unfortunately for
most, rain amounts will do little to beat back the developing
drought conditions. Rain should range from a couple hundredths in
the western zones to 1 10 to 1 4 inch in the central and northern
zones. Across the southeast zones however, a half inch to inch
will be possible as moisture and instability will be best in that
area. Any threat of surface based instability will remain well to
the south of the cwa, but a few rumbles of thunder may sound
across the eastern half of the region. This round of rain will be
quick hitting and exit after midnight. Sunday will be a pleasant
day with lots of sunshine and light westerly winds, which will
help boost temps into the low 70s in the southwest and 60s elsewhere.

The various forecast models don't really know how to handle the
upper level vorticity centers across the baja area Sunday night
and Monday. The 12z ECMWF threw out a unique solution and combined
all of the centers into a potent upper low that it ejects on
Tuesday and brings a round of widespread rain to the area. The
other guidance shoots this energy across in pieces and thus the
lift and ability to get gulf moisture back into the area are
unimpressive. In any case will continue with a slight chance of
showers over the southeast half of the area on Monday. Have
extended these pops into Tuesday for the same area out of respect
for the ECMWF solution, but if the ECMWF forecast starts to look
more correct these pops will need to be raised dramatically.

Otherwise above normal temperatures look to prevail Monday and
into Wednesday with highs in the mid to upper 60s. Lows will be in
the upper 30s to upper 40s. By Thursday highs should warm to near
70 ahead of our next cold front.

Big changes are in store by the end of the week as an upper level
longwave trough gets carved out across the western us. Upper level
height rises along the pacific coastline of canada will foster the
development of a 1040mb surface high across montana by Thursday.

This will send arctic air southward into the plains during the day
Thursday... Reaching north central texas Thursday night. There is
excellent model agreement in timing the arrival of this cold
airmass and therefore confidence in the temperature forecast is
quite high. Furthermore, the positioning of the surface high and
evolution of the upper level pattern is a classic one that brings
cold air into the region and often results in the coldest temps
across our western zones (i.E. Not a north-south temp gradient but
west to east). Lows will likely reach freezing across the nw
zones by Friday with highs Friday likely stuck in the low to mid
40s. Northerly winds at 10-20 mph will make it feel even colder.

The high temperature forecast will be contingent on how quickly
cloud cover can develop behind the front, so those temps could end
up colder, but have stayed somewhat conservative.

The following discussion concerns weather beyond the 7 day
forecast period, but there is enormous interest in the weather
ahead of christmas for travel (and those dreaming of a white
christmas). Confidence remains low about the eventual fate of the
upper level pattern, particularly on how (or whether) the upper
level low develops at the base of the deepening upper trough. This
isn't a situation where one model is consistently saying
something and we're waiting to see if the others jump on board.

This is worse. All of the models keep saying something different
essentially each run and trading places with each other. What
that means is that there are probably 3 reasonable forecast
solutions:
1) the upper low never develops and the trough remains somewhat
progressive. This would result in a clear and cold forecast
outcome. 2) the upper low develops and sinks into the desert
southwest or baja region. This would likely result in winter
weather somewhere in our region (not necessarily our cwa). 3) the
upper low develops and drops southwest into the pacific ocean too
far to provide lift or moisture here. This forecast also would
result in little or no winter weather for our CWA with temps not
quite as cold as either of the first 2 scenarios.

Scenario 2 is the one that most of the guidance is showing today
and the one we've got a gut feeling may verify since upper lows
have been developing and dropping into that region for the last
week or so. However, the difference in the strength and exact
location of the upper low determine where, when, what and how much
winter precipitation fall and it's just too early to get too
involved in those details.

What we can do is use climatology as a guide. This upper level
pattern with a closed low in that region can produce snow in
texas, but snow is typically favored across the western half of
the state. In general it is too warm aloft here, and our CWA ends
up with freezing rain or sleet. This likely means that ice or
freezing rain around dec 23rd are a higher probability than snow
and western areas are favored more than eastern areas. If that
low were to eject northeastward it would help cool the atmosphere
aloft and would increase the chances for snow on the 24th and
25th. Again given the wild model variability of late, we can't say
that will occur with any confidence either. Finally to get some
percentage numbers based on ensemble guidance... Half of the gefs
members and a third of the ECMWF ensemble members do show a winter
event in our cwa. Ensembles are underdispersive to true
probabilities so those probability chances don't correlate
exactly. In any case this is going to bear watching.

So in summary:
1) strong cold front arrives Thursday night.

2) colder than normal weather for dec 22nd to 25th is a near
certainty.

3) precipitation behind the front is possible with probabilities
of some type of winter event somewhere in our CWA around 25%
4) it is much too soon to get into the details of what, where, and
how much... But dec 23-25th is the window, ice sleet may be
favored (at least initially) and western areas have a higher
chance than eastern areas.

Tr.92

Aviation issued 1131 am cst Fri dec 15 2017
while flying weather is generally good today... We have received several
pireps of moderate to severe turbulence between fl170 and fl250.

This turbulence is associated with a potent jet stream which is
currently passing through northern portions of our forecast area.

This jet should move out of our area by evening... Allowing for
this turbulence to diminish.

Vfr is forecast to prevail through the TAF period. N'ly flow
conditions are in place across the region... With a transition to
s'ly flow expected late this evening as a trough of low pressure
develops across the southern high plains. Cloud cover will begin
to increase after 16 1500z... But ceilings should remainVFR
through the TAF period. Winds will increase on Saturday as
well... Though this is not mentioned explicitly in the tafs as
winds should remain s'ly.

Just beyond the TAF period... Expect chances for shra to increase
Saturday afternoon across central texas and spread into north
texas by evening. As the rain overspreads the area... Expect
conditions to deteriorate to MVFR... And possibly ifr for a time.

This rain should exit the area Sunday morning with conditions
improving throughout the day.

37

Preliminary point temps pops
Dallas-ft. Worth 39 61 45 68 46 0 30 80 5 10
waco 35 56 43 68 47 0 60 90 5 10
paris 32 59 43 58 45 0 5 100 10 10
denton 32 62 43 66 44 0 20 80 5 10
mckinney 33 61 43 63 44 0 20 90 5 10
dallas 39 61 45 67 46 0 30 90 5 10
terrell 33 59 44 66 44 0 30 100 5 10
corsicana 37 57 44 67 47 0 40 100 5 10
temple 36 54 43 67 48 0 70 90 5 10
mineral wells 32 61 43 70 41 0 30 70 0 10

Fwd watches warnings advisories
None.



Weather Reporting Stations
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Airport Reports
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AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Fort Worth, Naval Air Station, TX9 mi51 minN 010.00 miA Few Clouds55°F21°F26%1021.6 hPa
Fort Worth, Meacham International Airport, TX10 mi50 minN 010.00 miFair53°F23°F31%1022.8 hPa
Fort Worth, Fort Worth Alliance Airport, TX11 mi50 minN 010.00 miA Few Clouds52°F21°F30%1023.5 hPa
Decatur, Decatur Municipal Airport, TX24 mi48 minN 010.00 miFair51°F21°F31%1022.3 hPa

Wind History from NFW (wind in knots)
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Last 24hrN10N8N6N10N7N6NW4NW6NW5NW4NW5NW8NW10NW11NW10N9NW8N8W4NW6NW7NE44Calm
1 day agoS56--S4NW4W3NW5NW7NW5NW6NW6NW5NW4NW4NW6N13NE17N15
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2 days agoNW6W4W5CalmCalmCalmS3S4CalmS4S7S5SE3S6S7S4SW8SW10SW15W14
G21
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W9SW9

Tide / Current Tables for
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Weather Map and Satellite Images
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Weather Map
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IR Satellite Image from GEOS
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Wind Forecast for Fort Worth, TX (18,4,5,8)
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Ground Weather Radar Station Dallas/Fort Worth, TX
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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.