Saturday, February23, 2019 L-36.com


Marine Weather and Tides
Gadsden, AL

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 6:18AMSunset 5:36PM Saturday February 23, 2019 3:39 PM CST (21:39 UTC) Moonrise 11:21PMMoonset 10:10AM Illumination 80% Phase: Waning Gibbous; Moon at 19 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


7 Day Forecast for Marine Location Near Gadsden, AL
   Hourly   EDIT   Help
location: 34.02, -85.99     debug


Area Discussion for - Birmingham, AL
      (on/off)   Help   NOTE: mouseover dotted underlined text for definition
Fxus64 kbmx 231836
afdbmx
area forecast discussion
national weather service birmingham al
1236 pm cst Sat feb 23 2019

Update
For 18z aviation.

Short term
Today and tonight.

* a significant threat for severe weather exists for the
northwestern half of central alabama this afternoon & overnight
period. Threats include strong tornadoes, damaging wind gusts
up to 60 mph, and quarter-size hail.

* greatest potential for all modes of severe weather will primarily
reside in areas currently outlined by the enhanced risk (3 5) &
moderate (4 5) risk areas northwest of interstate 59.

* a flood watch remains in effect for the northern half of central
alabama through 6 am Sunday morning.

Synopsis...

goes-east water vapor imagery & rap mesoanalysis depict a dynamic &
strengthening mid upper-level disturbance near the southern rockies.

This upper trough is exhibiting a neutral tilt with 500mb heights
~544 decameters. Ridging to our southwest has established a broad
swath of southwesterly 700-300mb flow with southeast to southerly
surface winds (depending on location relative to the surface front).

South of the front, southerly surface winds along with a 30-40 kt
850mb low-level jet have advected tropical air of caribbean origins
(pws 1.5-1.6" per 06z vortexse soundings) into the southern gulf
coast states. The warm front is now approaching tuscaloosa
southeastward towards eufaula as of 09z. Surface dewpoints south
of the front have generally ranged in the mid to upper 60s
overnight, though observation stations across southern ms &
southwestern al have shown dewpoints ~70-72 degrees (f) supportive
of SBCAPE already up to ~1,500 j kg. Areas of moderate to heavy
rainfall with embedded thunderstorms have lingered to our
northwest overnight across northern ms, northern al, & southern tn
where a dangerous flooding event is ongoing.

Discussion...

the primary upper-level feature to our west is progged to eject
northeastward into the great plains today & phase with the sub-
tropical jet. A strong h5 jet streak with winds in excess of 100 kts
is expected to develop at the base of the trough north of the
arklatex region. Despite not having the best jet streak orientation,
height falls & deep-layer forcing along with an eastward moving
surface front dry line feature will provide focus for downstream
convective initiation across the lower mississippi river valley
(mrv). Severe convective weather is expected across this region up
to an area generally where the warm front triple point sets up near
western ky tn. Afternoon boundary layer destabilization with surface
dewpoints in the upper 60s to near 70 is expected to increase sbcape
values to ~750-1,500 j kg, especially across the western & southern
portions of our forecast area where temperatures in the upper 70s &
lower 80s are possible given sufficient insolation & mixing. With
deep-layer shear values (50-60 kts 0-6km bulk shear, 400-500 0-3km
srh) & their orientation to the front trough, any stronger
storms updrafts will likely become supercellular across mississippi
& eventually into our western & northwestern counties in the late
afternoon evening. Low LCL heights (400-700 meters) & low-level wind
shear (300-400 0-1km srh) W broad hodograph curvature suggest any
organized thunderstorms supercells will carry a significant tornado
threat whether they remain discrete cells or manage to congeal into
a squall line or qlcs. Forecast soundings also suggest more robust
cape in the hail growth zone, so stronger storms will also carry an
isolated severe hail threat.

Currently forecast timing progs the threat for severe weather to
enter the northwest around 5 pm at which time severe parameters will
be high. Trends after sunset point to a general weakening of
instability as we lose diabatic heating, though the tropical airmass
will still support strong updrafts with sufficient SBCAPE values
~500-1,000 j kg. As this system moves eastward southeastward
towards the i-59 corridor (transition to slight risk area) its
orientation will become more parallel to shear vectors. This
eventually favors a diminishing tornado threat, though expect a
tornado threat through midnight & early morning. Damaging winds will
also carry a threat into this region if any stronger downdrafts can
transport LLJ energy to the surface. Loss of deep-layer forcing &
instability signal more weakening as the system approaches the i-85
corridor ~3 am Sunday where a transition to sub-severe conditions is
expected. Scattered pre-frontal showers & thunderstorms are also
expected throughout the morning & early afternoon, though latest
forecast soundings suggest an elevated mixed layer & associated
inversion aloft which would help to limit this activity.

A flooding threat persists across the northern half of central
alabama during this short-term period. Conditions have been much
worse as you head into northern ms al as well as tn, though many
locations across our north & northwest have experienced areal
flooding issues throughout the past several days including last
night & this morning. Though additional rainfall of 1-2" is forecast
in the short-term, especially in the far northwest, the transient
nature of this evening's system should limit flash flooding.

However, any training showers & elevated thunderstorms north of the
warm front this morning will only exacerbate any ongoing local
flooding in low-lying poor drainage areas as well as local streams &
rivers which are already at or above their banks & into flood stage.

Please refer to our hydrologic & flooding products for more specific
& detailed information.

Maintain multiple ways to receive vital information on watches or
warnings today & into early Sunday morning. Stay tuned to local news
or a NOAA weather radio & refer back frequently for forecast
updates. Take immediate action if you are placed under any severe
thunderstorm or tornado warnings.

40 sizemore

Long term
Sunday through Friday.

We will continue to see some of the leftover rain in the far
southeast through 9 to 10 am Sunday, but then we can say goodbye to
the rain for a few days. Sunday and Monday will be dry as high
pressure will be in control. Much of Tuesday will be dry as well,
but we will begin to see an increase in clouds as the high begins to
to exit the region and the southerly flow begins to increase across
the area once again.

By Tuesday night, low pressure develops along the gulf coast and
slides slowly across the area. This will be the first wave of
several upper level wave that will slide through the area through
Friday ahead of the next cold front that will work into the area
Friday night and move out by Saturday morning.

Synoptically this pattern makes sense and will be the overall
forecast for the time being, but there are some model discrepancies
in regards to position of the main vorticity MAX and support of the
system. The more bullish system, the gfs, has the main support in
the north and drags the front through with very little wrap around
behind it. This would entail a fairly dry weekend for the extended.

The euro, brings things a touch further south and therefore brings
the upper level low a little further south. This would provide more
clouds and some linger light rain into Saturday. Right now either
scenario is plausible and will need to monitor over the next few
days the trends of each solution. But for now the main focus will
be on the system moving the area through tonight.

16

Aviation
18z TAF discussion.

Some clearing has begun to take place at our southern and western
sites this afternoon due to placement of the warm front. Winds
and the chances for showers will increase through the afternoon
into this evening ahead of an approaching cold front. Most of the
activity will be between 21z this afternoon until 10-11z Sunday. Have
included showers and vcts as early as 21z for ktcl while kasn,
kanb, kmgm, and ktoi will see this activity a little later
(04-05z). Did include prob30 tsra for our northern sites beginning
at the specified onset time and continuing for a few hours.

Amendments in timing could be needed as storms starts developing.

Wind gusts will generally range between 15-25kts and possibly
higher at times. Shower storm activity will end west to east
overnight. Currently have activity dissipating at ktcl by 07z and
at 11-12z for ktoi. Winds will remain elevated, generally
10-15kts, at all sites even with the dissipation of
showers storms.

07

Fire weather
A prolonged period of rainfall will continue through Sunday
morning, with a strong storm system expected to move through
central alabama today and tonight. Very wet conditions are
expected, especially across the northern half of the area. Drier
conditions return to the area for at least a couple days to start
next week. There are no fire weather concerns at this time.

Preliminary point temps pops
Gadsden 52 60 34 59 34 90 10 0 0 0
anniston 53 62 35 60 36 80 10 0 0 0
birmingham 52 61 36 61 38 90 10 0 0 0
tuscaloosa 51 62 36 62 39 90 0 0 0 0
calera 53 62 38 61 38 80 10 0 0 0
auburn 58 65 39 62 40 80 20 0 0 0
montgomery 58 67 39 66 40 80 10 0 0 0
troy 59 67 40 65 41 80 20 0 0 0

Bmx watches warnings advisories
Flood watch through late tonight for the following counties:
bibb... Blount... Calhoun... Cherokee... Clay... Cleburne... Etowah...

fayette... Jefferson... Lamar... Marion... Pickens... Shelby... St.

Clair... Talladega... Tuscaloosa... Walker... Winston.



Weather Reporting Stations
   EDIT       (on/off)   Help   NOTE: Click on distance to see the station location on a map

Airport Reports
    EDIT      (on/off)   Help   Click EDIT to display multiple airports
AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Gadsden, Gadsden Municipal Airport, AL6 mi44 minENE 1110.00 miOvercast58°F57°F100%1014.6 hPa
Albertville, Albertville Municipal Airport, AL20 mi65 minESE 510.00 miOvercast59°F55°F88%1013.9 hPa

Wind History from GAD (wind in knots)
9
AM
10
AM
11
AM
12
PM
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
Last 24hrNE5E7NE6CalmE6NE7NE8NE8NE9NE7NE7NE9NE8E10E9E9E7NE6E6E8NE6E3SE5Calm
1 day agoNE5NE3NE3NE6E4NE7NE7NE8NE8NE11N6NE10NW5NE8NE6E6NE6NE7NE6NE7NE8NE7NE9NE8
2 days agoE5E7E5NE6E6E11E7NW6NE4E6E6E6NE5E5NE4NE4E5NE8E3E4NE4NE3NE4E7

Tide / Current Tables for
   EDIT   RT Ports Option   Weekend mode (on/off)   (on/off)   Help
Tide / Current Tables for
   EDIT      (on/off)   Help
Weather Map and Satellite Images
       (on/off)   HelpWeather Map
wmap_A
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.
Link to Loop

Other links: Northern Pacific     Contential US     Full GOES-East
Wind Forecast for Birmingham, AL (16,3,4,5)
      (on/off)   Help

Ground Weather Radar Station Northern Alabama
   (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.