Area forecast discussion
National Weather Service New Orleans la
807 PM CDT Friday may 24 2013
Sounding discussion...
no problems with The Launch this evening. Dry adiabatic lapse rate
surface to 795 mb/7000 feet...mild subsidence inversion to 8100 feet
then adiabatic lapse rate to another inversion at 400 mb/24.8kft.
Tropopause at 166 mb/44.2kft. Moisture profile has a bit of an
inverted v from surface to lower inversion where a 2c depression
is as saturated as the sounding gets...then dry above 795 mb.
Precipitable water 1.44 inches and positive area 2256 j/kg was
enough to get convection along frontal boundary that moved through
prior to launch. Winds have a northerly component throughout
entire run...north-northeast 5-15 knots to 7500 feet...then variable northwest-north 15-20kt
to 23... solidly northwest-west-northwest 20-75kt through tropopause and
lower stratosphere. Peak wind 294/73kt at 43.9kft.
Finally...balloon burst 21 miles southeast downrange over Lake
Borgne near Alligator Point at an altitude of 33.7 km /110790 feet
or 20.9 miles up. 24/rr
&&
Previous discussion... /issued 324 PM CDT Friday may 24 2013/
Discussion...
Frontal boundary continues to push across south Louisiana this
afternoon. Interactions with lake breeze fronts helped trigger a
few thunderstorms. As the front continues to push south towards
the coast...expect for additional isolated thunderstorms to
continue.
Behind the front...a drier airmass will begin to spill in as a
ridge of high pressure begins to settle in. Expect for dry
conditions to prevail at least through the early part of next
week. The center of high pressure will centered over the Atlantic
for much of next week...establishing a prolonged southeast flow.
Expect for moisture to slowly return to the area which will allow
for afternoon thunderstorms to develop starting Wednesday and
continue through the rest of the forecast period.
7/arm
Aviation...
Isolated thunderstorms could affect some of the taf locations late
this afternoon...mainly those west of Interstate 55.
Otherwise...no other aviation concerns are expected over the
remainder of the forecast period.
Marine...
A drier airmass is expected to move across the coastal waters
tonight as a ridge of high pressure moves in from the northeast.
This airmass will produce a steady breeze extending from the
sounds out to 60 nm. As a result...a small craft caution is in
effect after midnight tonight through early Saturday morning. Wind
is expected to slowly shift to the southeast late in the weekend
and towards early next week. Given the prevailing pattern...expect
for seas to increase towards the end of the forecast period as a
long southeast fetch established itself over the Gulf.
7/arm
Decision support...
Dss code...blue.
Deployed...none.
Activation...none.
Activities...slurry support.
Monitoring river flooding.
Decision support services (dss) code legend
green = no weather impacts that require action
blue = long fused watch/warning/advisory in effect or high
visibility event
yellow = heightened impacts with short fused
watch/warning/advisory issuances; radar support
Orange = high impacts - slight to moderate risk severe; nearby
tropical events; hazmat or other large episodes
red = full engagement for moderate to high risk severe
and/or direct tropical threats; events of National
significance
&&
Preliminary point temps/pops...
mcb 58 87 59 86 / 10 10 0 0
btr 65 89 64 87 / 10 10 0 0
asd 63 86 61 85 / 10 0 0 0
msy 69 87 67 84 / 10 0 0 0
gpt 62 84 64 83 / 10 0 0 0
pql 57 85 59 85 / 10 0 0 0
&&
Lix watches/warnings/advisories...
la...none.
GM...none.
MS...none.
GM...none.
&&
$$
