Flash Flood Warning 17, NWS New Orleans, LA

Area Forecast Discussion
National Weather Service New Orleans LA
408 PM CDT Fri Jun 23 2017

.SHORT TERM...
Southwesterly flow in place across the area in response to the
broad circulation of remnant Cindy currently moving into the Ohio
Valley. The frontal zone is being drawn southward with an
extensive coverage of convection reaching central Louisiana. This
convection will likely continue into the evening and quite
possibly overnight. The HRRR runs this afternoon is advocating an
outflow QLCS advancing southward after midnight, but other models
are focused mainly along the frontal zone itself. Will maintain
40-50 percent in the overnight, then carry into Saturday. The rain
trends will have to be closely monitored for echo training as
efficient tropical airmass becomes involved with the frontal zone
that will probably be moving on the impetus of the convection.
Frontal zone stalls out for continued chances of rain Sunday.
Temperatures will vary widely depending on rain coverage but
generally in the upper 80s for highs though one or two locations
may attain 90 either day.

.LONG TERM...
Models show enough troughing aloft to possibly push the front into
the north gulf for a very brief dry period Monday before moist
begins to surge northward Tuesday. Bermuda ridge regime becomes
established to bring the area under a more typical summer sea
breeze pattern for the latter part of the forecast period. 24/RR

&&

.AVIATION...
A very moist and unstable pattern will continue to bring widespread
showers and storms into the area.  Convection will continue to
increase from nw to se...peaking between 2100 and 00z this evening
bringing conditions down from MVFR to IFR during the heavier storms.
Convection expected to gradually diminish after 02Z.  Lower ceilings
expected to drop down below 2000 feet between 06 and 12z. Convection
will begin to refire after 15z on Saturday and continue to become
more widespread throughout the late morning into the afternoon
hours.

&&

.MARINE...
Winds and seas are finally relaxing from the affects of Cindy with
more favorable conditions this weekend as pressure gradient
relaxes. Frontal zone not expected to push much into the gulf
before stalling and drawn northward early next week, thereby
onsetting a steady state onshore flow pattern for the rest of the
week.

&&

.DECISION SUPPORT...
DSS code: Blue.
Deployed: None.
Activation: None.
Activities: Monitoring Hydro/Convective trends

Decision Support Services (DSS) Code Legend
Green  = No weather impacts that require action.

Blue   = Long-fused watch, warning, or advisory in effect or high
         visibility event.

Yellow = Heightened impacts with short-fused watch, warning or
         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 risk of severe and/or
         direct tropical threats; Events of National Significance.

&&

.PRELIMINARY POINT TEMPS/POPS...
MCB  73  84  71  83 /  50  80  50  60
BTR  75  87  73  84 /  40  80  50  60
ASD  75  88  74  84 /  40  50  40  60
MSY  76  88  75  84 /  40  50  30  60
GPT  76  86  75  83 /  40  40  40  60
PQL  74  87  73  84 /  20  50  50  50

&&

.LIX WATCHES/WARNINGS/ADVISORIES...
LA...Coastal Flood Advisory until 4 PM CDT this afternoon for LAZ040-
     050-058-060>062-064-066>070-072.

GM...Small Craft Advisory until 4 PM CDT this afternoon for GMZ532-
     534-536-538-550-552-555-557-570-572-575-577.

MS...Coastal Flood Advisory until 4 PM CDT this afternoon for
     MSZ080>082.

GM...Small Craft Advisory until 4 PM CDT this afternoon for GMZ534-
     536-538-550-552-555-557-570-572-575-577.

&&

24/RR

Hazardous Weather Outlook
National Weather Service New Orleans LA
436 PM CDT Fri Jun 23 2017

GMZ530-532-534-536-538-550-552-555-557-570-572-575-577-LAZ034>037-
039-040-046>050-056>072-MSZ068>071-077-080>082-240945-
Lake Pontchartrain and Lake Maurepas-Mississippi Sound-
Lake Borgne-Chandeleur Sound-Breton Sound-
Coastal Waters from Port Fourchon LA to Lower Atchafalaya River
LA out 20 nm-
Coastal waters from the Southwest Pass of the Mississippi River
to Port Fourchon Louisiana out 20 NM-
Coastal Waters from Boothville LA to Southwest Pass of the
Mississippi River out 20 nm-
Coastal waters from Pascagoula Mississippi to Stake Island out
20 NM-
Coastal waters from Port Fourchon Louisiana to Lower Atchafalaya
River LA from 20 to 60 NM-
Coastal waters from Southwest Pass of the Mississippi River to
Port Fourchon Louisiana from 20 to 60 NM-
Coastal Waters from Stake Island LA to Southwest Pass of the
Mississippi River from 20 to 60 nm-
Coastal waters from Pascagoula Mississippi to Stake Island
Louisiana out 20 to 60 NM-Pointe Coupee-West Feliciana-
East Feliciana-St. Helena-Washington-St. Tammany-Iberville-
West Baton Rouge-East Baton Rouge-Ascension-Livingston-Assumption-
St. James-St. John The Baptist-Upper Lafourche-St. Charles-
Upper Jefferson-Orleans-Upper Plaquemines-Upper St. Bernard-
Upper Terrebonne-Lower Terrebonne-Lower Lafourche-Lower Jefferson-
Lower Plaquemines-Lower St. Bernard-Northern Tangipahoa-
Southern Tangipahoa-Wilkinson-Amite-Pike-Walthall-Pearl River-
Hancock-Harrison-Jackson-
436 PM CDT Fri Jun 23 2017

This Hazardous Weather Outlook is for portions of Southeast
Louisiana...South Mississippi and the adjacent coastal waters.

.DAY ONE...Tonight

A Coastal Flood Advisory remains in effect for all of coastal
Southeast Louisiana including around Lake Pontchartrain and
Maurepas and all of coastal Mississippi through 6 pm Friday.
Persistent onshore winds will keep tides elevated 1 to 2 feet
above normal. Expect low lying coastal roads to be most impacted
by this coastal flooding.

Scattered to numerous thunderstorms are anticipated through the
evening hours, primarily through the evening hours While severe
weather is not expected, a few thunderstorms could produce very
heavy rain. This could cause brief street flooding in some areas,
especially in those areas hard hit by heavy rains over the last
few days.

Strong onshore winds of 20 to 25 knots and very rough seas will
continue in the coastal waters through this afternoon.

.DAYS TWO THROUGH SEVEN...Saturday through Thursday

Scattered to numerous thunderstorms will be possible Saturday and
Sunday. While severe weather is not expected, some storms could
produce very heavy rain. Otherwise, the threat of hazardous
weather is low through Thursday.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not anticipated.