UPDATED 1:50 P.M.: Cristobal expected to bring heavy rain

From National Weather Service at 10 a.m.

Cristobal is a tropical depression over Mexico, but is expected to move north across the Gulf of Mexico late Friday through the weekend.

Flooding is our top concern – from both storm surge and rainfall. We are expecting one to six inches of rain, with locally higher amounts this weekend into early next week. Tides are already running a foot above normal and will likely increase this weekend.

Winds will be tropical storm force in parts of south central Louisiana. Expect scattered power outages Sunday and Monday.

Roger Erickson
Warning Coordination Meteorologist

The National Weather Service's "most reasonable worst-case scenario" for Tropical Storm Cristobal is landfall near or to the west of the Tri-City area. It would bring 10-15 inches of rain in 48 hours east of the center and 8-10 inches to the west, Gov. John Bel Edwards said at his Wednesday press conference.

The current track prediction is for the center of the storm to come ashore in the Atchafalaya-Vermilion Bay area, Edwards said.

Five days out, that predicted track is far from certain.

But "it looks like it's got its sights set on Louisiana ...," Edwards said. "What we anticipate is that it will be a very severe weather event in Louisiana."

The five-day track prediction has the center of the storm reaching land late Sunday or early Friday. The five-day prediction "cone" indicates landfall is possible anywhere from Galveston to the Mississippi-Alabama border.

Whatever rain Cristobal brings is likely to fall on ground already saturated by days of rain leading up to the landfall, Edwards said.

The Tri-City area has a 40-60% chance of storms each day through Saturday, according to the National Weather Service forecast.

Some areas are already under flash flood advisories, and the state is monitoring gates in the statewide flood control system, Edwards said.

One positive is that this year's river levels are lower than when Hurricane Barry approached the Louisiana coast last year, Edwards said.

Barry's storm surge pushed the Atchafalaya to over 10 feet in Morgan City on July 13, 2019, at the tail end of a flood season that had started around Mardi Gras.

Water may not be Cristobal's only threat. In addition to the storm surge, the storm may approach the coast with 60 mph winds, Edwards said.

Hurricane Barry's winds, which barely exceeded the 74 mph threshold for hurricanes, were enough to knock out power to nearly every part of St. Mary for most of a weekend.

The governor urged residents to prepare now for Cristobal.

"Put your family in the best possible position to ride out the first 72 hours of the storm," Edwards said.

That means making sure you have enough water, batteries, charged cell phones and, in these days of COVID-19 mitigation, items such as hand sanitizer.

Tropical Depression Cristobal Discussion Number 12
NWS National Hurricane Center Miami FL AL032020
1000 AM CDT Thu Jun 04 2020

With the center remaining inland, Cristobal has continued to
weaken, and the cloud pattern is becoming disorganized. The
current intensity is reduced to 30 kt for this advisory, and the
warnings for the Bay of Campeche coast of Mexico have been
discontinued. Assuming that the center will emerge over the Gulf of
Mexico in about 36 hours, re-intensification should begin by
tomorrow evening. The environment over the Gulf of Mexico is not
expected to be very conducive for intensification, with moderate
southwesterly shear and some dry mid-level air. Not surprisingly,
the intensity guidance, such as HWRF and LGEM, are not very bullish
on strengthening. The official forecast remains a little above the
latest intensity model consensus. It should still be noted,
however, that there is some uncertainty as to the strength of
Cristobal when it reaches the northern Gulf of Mexico coast due to
the limitations of forecasting tropical cyclone intensity change.

The cyclone continues to move slowly east-southeastward, or 120/3
kt. Over the next day or so, Cristobal is likely to move along a
partial cyclonic loop while embedded within a broader gyre. By
tomorrow night, the system should have begun moving northward into
a weakness in the subtropical ridge. This generally northward
motion should continue until the center crosses the northern
Gulf coast. There have been no important changes to the NHC track
forecast, which is a blend of the simple and corrected dynamical
model consensus aids.

The global models indicate that Cristobal's wind field will expand
as the cyclone deepens over the south-central Gulf of Mexico.
Therefore, the size of the NHC wind radii have again been increased
primarily over the eastern semicircle at 36-72 hours. Indeed,
the models suggest that when the storm reaches the northern Gulf
coast, the worst conditions may occur at a large distance from the
center.

Key Messages:

1. Damaging and deadly flooding has already been occurring in
portions of Mexico and Central America. Cristobal is expected to
produce additional extreme rainfall amounts through the end of the
week. The heaviest additional rainfall is expected over far
southern Mexico and portions of the Yucatan Peninsula, while also
extending along the Pacific coast from Chiapas to Guatemala and El
Salvador. This rainfall could cause widespread life-threatening
flash floods and mudslides. Refer to products from your local
weather office for more information.

2. Cristobal is forecast to re-emerge over the southern Gulf of
Mexico on Friday and move northward over the central and northern
Gulf of Mexico over the weekend. There is a risk of tropical storm
force winds this weekend from Louisiana to the western Florida
Panhandle and a risk of dangerous storm surge from Louisiana to the
Florida Big Bend. These hazards, along with heavy rainfall, will
arrive well in advance of and extend well east of Cristobals
center. Tropical storm and storm surge watches could be issued
tonight or Friday.

FORECAST POSITIONS AND MAX WINDS

INIT 04/1500Z 17.6N 91.0W 30 KT 35 MPH...INLAND
12H 05/0000Z 17.7N 90.5W 30 KT 35 MPH...INLAND
24H 05/1200Z 19.0N 90.2W 30 KT 35 MPH...INLAND
36H 06/0000Z 21.0N 90.3W 35 KT 40 MPH...NEAR THE COAST
48H 06/1200Z 22.9N 90.7W 40 KT 45 MPH...OVER WATER
60H 07/0000Z 24.7N 90.7W 45 KT 50 MPH...OVER WATER
72H 07/1200Z 26.7N 90.6W 50 KT 60 MPH...OVER WATER
96H 08/1200Z 30.8N 91.7W 35 KT 40 MPH...INLAND
120H 09/1200Z 35.0N 91.5W 25 KT 30 MPH...INLAND