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Tropical Depression Ida Advisory Number 19
NWS National Hurricane Center Miami FL AL092021
400 PM CDT Mon Aug 30 2021
...IDA BECOMES A TROPICAL DEPRESSION OVER MISSISSIPPI...
...HEAVY RAINFALL AND FLASH FLOODING THREAT CONTINUES TO SPREAD
SUMMARY OF 400 PM CDT...2100 UTC...INFORMATION
ABOUT 20 MI...35 KM NNW OF JACKSON MISSISSIPPI
MAXIMUM SUSTAINED WINDS...35 MPH...55 KM/H
PRESENT MOVEMENT...NNE OR 20 DEGREES AT 9 MPH...15 KM/H
MINIMUM CENTRAL PRESSURE...999 MB...29.50 INCHES
WATCHES AND WARNINGS
CHANGES WITH THIS ADVISORY:
All Tropical Storm and Storm Surge Warnings have been discontinued.
SUMMARY OF WATCHES AND WARNINGS IN EFFECT:
There are no coastal watches and warnings in effect.
DISCUSSION AND OUTLOOK
At 400 PM CDT (2100 UTC), the center of Tropical Depression Ida was
located near latitude 32.6 North, longitude 90.3 West. The
depression is moving toward the north-northeast near 9 mph (15
km/h). A faster northeastward motion is expected tonight through
Wednesday. On the forecast track, the center of Ida will move
farther inland over central and northeastern Mississippi tonight.
Ida is then forecast to move across the Tennessee Valley on
Tuesday and near the central Appalachians on Wednesday.
Maximum sustained winds have decreased to near 35 mph (55 km/h)
with higher gusts. Additional weakening is forecast during the
next day or so.
The minimum central pressure estimated from surface observations is
999 mb (29.50 inches).
HAZARDS AFFECTING LAND
Key messages for Ida can be found in the Tropical Cyclone
Discussion under AWIPS header MIATCDAT4, WMO header WTNT44 KNHC,
and on the web at hurricanes.gov/graphics_at4.shtml?key_messages.
STORM SURGE: Water levels along the northern Gulf coast should
continue to subside through this evening.
RAINFALL: Through Tuesday morning across portions of southeast
Louisiana into far southern Mississippi, Ida will produce additional
rainfall totals of 2 to 4 inches with localized higher amounts
possible. Storm total rainfall accumulations of 10 to 18 inches with
isolated maximum amounts of 24 inches is expected. Heavy rain
combined with storm surge has resulted in catastrophic impacts along
the southeast coast of Louisiana with considerable flash flooding
and riverine flooding continuing farther inland.
Ida will continue to turn northeast this evening and is forecast to
track across the Middle Tennessee Valley, Ohio Valley and
Mid-Atlantic through Wednesday, producing the following rainfall
Coastal Alabama to the far western Florida panhandle: An additional
3 to 6 inches resulting in storm total accumulations of 6 to 12
inches with isolated maximum amounts of 15 inches, today through
Central Mississippi into far western Alabama: 4 to 8 inches with
isolated maximum amounts of 12 inches, today through tonight.
Middle Tennessee Valley, Ohio Valley, Central/Southern Appalachians
into the Mid-Atlantic: 3 to 6 inches with isolated higher amounts,
Tuesday into Wednesday.
Southern New England: 2 to 4 inches with isolated higher amounts,
Wednesday into Thursday.
Considerable flash flooding is possible from the Lower Mississippi
Valley through the Middle Tennessee Valley, Ohio Valley,
Central/Southern Appalachians, and into the Mid-Atlantic. Widespread
minor to isolated major riverine flooding is occurring or forecast
from the Lower Mississippi Valley into far western Alabama. Rivers
will remain elevated into next week.
TORNADOES: A few tornadoes are possible through tonight, mainly
across far southeast Mississippi, the southern half of Alabama, and
the western Florida Panhandle. The threat for a few tornadoes will
shift east on Tuesday and become centered across eastern Alabama,
western Georgia, and the Florida Panhandle.
SURF: Swells will continue to affect portions of the northern Gulf
coast through this evening. These swells are likely to cause life-
threatening surf and rip current conditions. Please consult
products from your local weather office.
This is the last public advisory issued by the National Hurricane
Center on Ida. Future information on Ida can be found in Public
Advisories issued by the Weather Prediction Center beginning at 10
PM CDT, under AWIPS header TCPAT4, WMO header WTNT34 KWNH, and on
the web at http://www.wpc.ncep.noaa.gov.