Tropical Storm Cristobal Forecast Discussion Number 11

By | June 4, 2020

Issued at 400 AM CDT Thu Jun 04 2020


000
WTNT43 KNHC 040844
TCDAT3
 
Tropical Storm Cristobal Discussion Number  11
NWS National Hurricane Center Miami FL       AL032020
400 AM CDT Thu Jun 04 2020

Satellite imagery and radar data from Sabancuy, Mexico indicate 
that Cristobal has resumed a southeastward drift and moved farther 
inland.  There is no data from near the core of the storm, so the 
maximum intensity is set to a possibly generous 35 kt based on 
continuity from the previous advisory and earlier scatterometer 
data that showed 35 kt winds over water to the northwest of the 
center.

The initial motion is a drifting 125/2 kt.  A slow eastward motion 
is expected today.  After that, southerly flow associated with a 
strengthening ridge over the western Atlantic and a developing 
mid-/upper-level trough over northern Gulf of Mexico should turn 
Cristobal northward with some increase in forward speed.  Later in 
the forecast period, a north-northwestward or northward motion is 
expected as Cristobal interacts with the trough, with most of the 
track forecast guidance bringing the system to the northern Gulf 
coast between 96-120 h.  The new forecast track has no significant 
changes from the previous track, and it lies near the various 
consensus models.

Cristobal should weaken to a depression in the next few hours as 
the center drifts farther inland.  Little subsequent change in 
strength is likely through 24 h due to much of the circulation 
remaining over water.  By 36 h, the global model guidance suggest 
that winds will increase over the Gulf of Mexico well northeast of 
the center, so the new intensity forecast calls for Cristobal to 
regain tropical storm status at that time.  From 48-120 h, Cristobal 
is forecast to interact with the trough over the Gulf of Mexico, 
which is likely to cause dry air entrainment and some shear.  The 
intensity guidance suggests these conditions will allow only 
gradual intensification, so the new forecast follows the trend of 
the previous forecast in showing a peak intensity of 50 kt before 
landfall on the northern Gulf coast.  
 
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 was already 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. Even though Cristobal is inland, tropical storm conditions will 
continue along and near the coast of Mexico for a few more hours, 
especially over western Campeche, eastern Tabasco, and northern 
Chiapas states.
 
3. 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 storm surge,
heavy rainfall, and wind impacts beginning over the weekend along
portions of the U.S. Gulf Coast from Texas to the Florida Panhandle.
While it is too soon to determine the exact location, timing, and
magnitude of these impacts, interests in these areas should monitor
the progress of Cristobal and ensure they have their hurricane plan
in place.
 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  04/0900Z 17.9N  91.3W   35 KT  40 MPH...INLAND
 12H  04/1800Z 18.0N  91.0W   30 KT  35 MPH...INLAND
 24H  05/0600Z 18.7N  90.5W   30 KT  35 MPH...INLAND
 36H  05/1800Z 20.2N  90.4W   35 KT  40 MPH...INLAND
 48H  06/0600Z 22.1N  90.5W   40 KT  45 MPH...OVER WATER
 60H  06/1800Z 23.9N  90.7W   45 KT  50 MPH
 72H  07/0600Z 25.8N  90.8W   50 KT  60 MPH
 96H  08/0600Z 29.5N  91.5W   50 KT  60 MPH
120H  09/0600Z 34.0N  92.5W   30 KT  35 MPH...INLAND
 
$$
Forecaster Beven
 

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