Tropical Storm Cristobal finally mad the turn north and got a pretty decent kick, too. As of the morning advisory, it was moving at 12mph. The Forecast takes it north across the Gulf of Mexico and into Louisiana by Sunday.
But that isn’t the only place that will experience weather from Cristobal. Here is the latest from the National Hurricane Center:
SUMMARY OF 100 PM CDT…1800 UTC…INFORMATION
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LOCATION…20.5N 89.8W
ABOUT 35 MI…60 KM SSE OF MERIDA MEXICO
ABOUT 595 MI…960 KM S OF THE MOUTH OF THE MISSISSIPPI RIVER
MAXIMUM SUSTAINED WINDS…40 MPH…65 KM/H
PRESENT MOVEMENT…N OR 360 DEGREES AT 12 MPH…19 KM/H
MINIMUM CENTRAL PRESSURE…1000 MB…29.53 INCHESAlthough the center of circulation is still over land, the system is gradually becoming better organized on satellite images. A large convective band has become better defined over the northern and eastern portions of the circulation. However, central convective features are still lacking. The current intensity estimate is 30 kt based on surface synoptic observations. Re-intensification should begin later today, and an Air Force Hurricane Hunter aircraft is scheduled to investigate Cristobal this evening as the center moves back over water. Additional intensification is anticipated through early Sunday, however this should be limited due to dry mid-level air and some shear. The official intensity forecast is about the same as in previous advisories and is near or above the latest intensity model consensus.
The cyclone is moving a little faster toward the north, or about 360/10 kt. For the next couple of days Cristobal should move mainly northward through a weakness between subtropical anticyclones. A gradual bend toward the north-northwest is likely after the center reaches the northern Gulf coast due to some building of a ridge to the northeast. The official track forecast is a little faster than the previous one and is a blend of the simple and corrected dynamical model consensus tracks.
Regardless of its exact track and forward speed, Cristobal is expected to have a broad and asymmetric wind field as it approaches the northern Gulf coast. The strongest winds, highest storm surge, and heaviest rains could be well removed to the east of the center of circulation. Therefore, it is important that users do not focus on the exact forecast path of the center of the cyclone.
Key Messages from the NHC
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. Life-threatening storm surge is possible along the Florida Big Bend, in portions of southeastern Louisiana, and along the Mississippi coast within the next 48 hours, and a Storm Surge Watch has been issued for these areas. Residents in these locations should follow advice given by local emergency officials.
3. There is an increasing risk of tropical storm force winds beginning Sunday morning from Intracoastal City, Louisiana, to the Alabama/Florida border, including metropolitan New Orleans, and a Tropical Storm Watch has been issued for this area. These winds will arrive well in advance of and extend well east of Cristobals center.
4. Heavy rainfall will spread onto portions of the Gulf Coast, from east Texas to Florida, this weekend into early next week, with areas of flash flooding and rapid rises on smaller streams and rivers
possible.
Quick satellite info
The orange colors on here show dry air in the lower levels. Notice how much is in and around Cristobal. This should keep Cristobal from rapidly intensifying, since some of this dry air continues to get pulled into the center of the storm.
Until the dry air is cut off from the center, Cristobal will continue to be one-sided and disorganized.
The Timeline
As of now, it looks like Tropical Storm Cristobal will emerge back into the Gulf later today and drift north during the daty on Saturday and then make landfall at some point on Sunday afternoon or evening.
Since this system is lopsided with most of the cloud cover and rain activity on the east and northeast side, that means the clouds and rain will begin before the landfall of the center. So clouds will increase along the Gulf Coast region on Saturday and the rain may begin as early as Saturday night late or early Sunday morning for some areas.
Cristobal will move north after landfall and curve back to the northeast during Sunday and into Monday. That may leave parts of Louisiana, Arkansas, Mississippi, Alabama and Tennessee with extended periods of rainfall with widespread totals up to 4″ to 6″ possible and a few spots topping 8″ of rain.
Cristobal should clear the Gulf Coast region by Monday night.
Model Data
The good news is a lot of the model data continues to come into pretty good agreement with where Cristobal is headed: North.
In fact, based on the maps from Alan Brammer, the GEFS data is more unsure about the timeline than the direction
The map above shows where the model thinks the center of the storm will be every twelve hours. When the circles are wider than they are tall, it means the model is more “unsure” about location than timing. When the circles are taller than wider, it means the model is more unsure about timing than location.
Notice that after landfall, the model is pretty sure it will be near the Mississippi River between Louisiana and Mississippi. It just isn’t sure how far inland it will be.
That is also an indication that this particular model is unsure about the forward speed of Cristobal.
And from that, we can pull out that it is also unsure about rainfall totals.
Piggybacking on that, the bad news is models are still disagreeing about how strong and organized Cristobal gets.
Even the SHIPS model, shown as one of the lines on the chart above, is showing some uncertainty about the potential for Rapid Intensification
What could change
A lot. The sea surface temperatures across the Gulf are warm. That is the lava color underneath the map above with the circles on it. However, more important than the overall sea surface temperatures is the available heat content of the Gulf. In other words, how deep does that warm water go?
Reasonably deep.
The 26-degree isotherm, an indication of how deep the warmer water goes, shows that the ‘warm enough to sustain a major hurricane’ water is almost 100 meters deep in the middle of the Gulf, ahead of where Cristobal is about to traverse.
The question becomes, how much of that will Cristobal have access to and use? While the forecasts shows Cristobal re-strengthening to a strong Tropical Storm, there is still a chance, given the warm water, that it makes a run at becoming a hurricane.
And, as you can imagine, that changes a lot of everything.
The Bottom Line
Prepare for one category higher than the forecast. That is what the National Weather Service always says. And it is a good piece of advice. So for now, the forecast is for a landfalling tropical storm. So prepare for a landfalling Category 1 hurricane.
And depending on your location, that could mean drastically different things. The further inland you are, the less the threat will be wind and the more the threat may be rain and brief spin-up tornadoes.
If you are in the Forecast Cone you need to be taking this storm seriously. While most time early season storms are weaker and Central American Gyre-born storms are disorganized, that is not reason to shrug off this storm.
Now is a good time to double check your Hurricane Preparedness Kit. Make sure that you have all of the supplies that you will need.
Start watching your local television meteorologist for forecast updates, checking with the National Hurricane Center every morning (you can read their updates on this website), or just check back here for updates, too.
Check out in your yard (if you have one) to see how you can mitigate your flooding risk. Usually these early season storms drop a lot – I mean, a LOT – of water. Some early estimates from the model data show the potential for some places to pick up over a foot of rain from whatever may drift north, regardless of strength. So take some steps now to look around your house and figure out what may help to move water away from your home and toward storm drains, creeks, or streams.
I want to take your meteorology class!