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Area forecast discussion...updated 
National Weather Service Mobile Alabama
1205 am CDT Sat Apr 18 2015

Aviation...
18.06z kmob/kbfm and kpns taf cycle...
patchy fog along with lowering stratus clouds expected overnight with
IFR visibilities and LIFR ceilings developing mainly between 18.10z
through 18.14z. The fog will lift quickly Saturday morning...with
ceilings lifting only slightly to MVFR criteria by 18.19z. Areas of
light rain with embedded moderate thunderstorms will move into the
area from the southwest during the afternoon hours...so added a
prob30 group after 18.18z. Winds will also increase from the south at
6 to 10 knots throughout the day. The areas of rain with embedded
moderate thunderstorms is expected to persist through the
evening...so added another prob30 group after 19.00z through the
remainder of the taf forecast. /22

&&

Previous discussion... /issued 726 PM CDT Friday Apr 17 2015/

Public update...a severe thunderstorm over southwest Washington
County will move into northern Mobile County along a weak outflow
boundary pushing south through the area. Another thunderstorm on its
heels will move over our inland southeast Mississippi counties
through the early evening hours. Hrrr model develops more shower and
thunderstorm activity further south across Mobile and Baldwin
counties through middle evening...and may even linger toward midnight.
Updated the grids and public products to now include isolated to
scattered showers and thunderstorms across our northwest zones
through midnight. Isolated showers are expected along the northern
Gulf coastal region after midnight...with patchy fog and low stratus
forming. Some locations could see visibilities lower to one-half mile
late tonight into Saturday morning...but would not be surprised to
see isolated pockets of dense fog due to the saturated ground from
recent rains. /22

Previous discussion... /issued 412 PM CDT Friday Apr 17 2015/

Short term...(tonight through saturday)...exiting shortwave will
have most of the current activity over the eastern half of the forecast area
out of the area by the beginning of the forecast. Later tonight into
Sunday...more energy swings around the base of an eastward
meandering upper low over the plains. The result is yet another
round of showers and thunderstorms moving over the area...mainly
Saturday afternoon into Saturday night. Pesky surface boundary
remains draped over the forecast area...north of i10...with a very moist
airmass south of the boundary. As the next round of energy moves
towards the forecast area Saturday...am expecting the surface boundary to move
north a bit...but with the low level winds being on the light
side...a strong northward push is not expected Saturday. What is
expected is enough instability over the southern half of the forecast area for
a thunderstorms or two to become strong to severe. /16

Long term...(saturday night through friday)...expect rainfall
across the region to be maximized as area lies in the warm sector
under a ridge of historical high precipitable water values of 2.0 inches with a
negatively tilted shortwave trough providing enough forcing for large
scale ascent. Timing will limit instability but suspect an organized
mesoscale convective system will have developed over Mississippi with enough shear to
sustain it as it propagates eastward over southwestern Alabama and western
Florida late Saturday night through early Sunday morning. There is a
marginal to slight risk of severe weather in the form of isolated
tornadoes or strong straight line winds and/or 1" hail. Should have
a Little Break if timing holds up the early part of Sunday...perhaps
through midday...then the next shortwave driving the cold front
should start to trigger storms over southeast Mississippi...possible
qlcs formation by late Sunday afternoon early evening...just not sure
how well it will sustain itself as main dynamics shift north and it
moves into the weakly sheared environment overlying the area. The
cold front should move through the area Monday...bringing a welcome
return to drier...more settled weather as an upper level ridge builds
aloft. /08

Marine...the surface trough that developed off the MS/al/NW Florida coast
this morning continues to fill...with strong onshore winds mainly from
Pensacola west have eased. /16

&&

Preliminary point temps/pops...
Mobile 66 76 69 81 66 / 30 80 80 60 30
Pensacola 68 77 70 80 68 / 30 60 80 80 30
Destin 70 75 70 76 72 / 30 60 70 80 30
Evergreen 63 77 68 83 66 / 30 60 80 70 30
Waynesboro 62 74 66 85 62 / 30 80 70 60 40
Camden 61 76 67 84 65 / 30 60 80 70 30
Crestview 67 81 68 80 66 / 30 60 70 80 30

&&

Mob watches/warnings/advisories...
Alabama...Flash Flood Watch through Sunday morning for Butler-Choctaw-
Clarke-Conecuh-Covington-Crenshaw-Escambia-lower Baldwin-
lower Mobile-Monroe-upper Baldwin-upper Mobile-Washington-
Wilcox.

High rip current risk through Saturday evening for lower Baldwin-
lower Mobile.

Florida...Flash Flood Watch through Sunday morning for coastal Escambia-
coastal Okaloosa-coastal Santa Rosa-inland Escambia-inland
Okaloosa-inland Santa Rosa.

High rip current risk through Saturday evening for coastal
Escambia-coastal Okaloosa-coastal Santa Rosa.

MS...Flash Flood Watch through Sunday morning for George-Greene-Perry-
stone-Wayne.

GM...Flash Flood Watch through Sunday morning for Choctawhatchee Bay-
coastal waters from Destin to Pensacola Florida out 20 nm-
coastal waters from Pensacola Florida to Pascagoula MS out 20 nm-
Mississippi Sound-northern Mobile Bay-Pensacola Bay system-
Perdido Bay-southern Mobile Bay-waters from Destin to
Pensacola Florida from 20 to 60 nm-waters from Pensacola Florida to
Pascagoula MS from 20 to 60 nm.

&&

$$

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