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Norbert pounds Baja

By: Dr. Jeff Masters, 4:24 PM GMT on October 11, 2008

An area of disturbed weather (97L) midway between Africa and the Lesser Antilles Islands continues to slowly organize. Wind shear is a moderate 10-15 knots over the disturbance, and waters are warm, about 29° C. Satellite loops and this morning's QuikSCAT pass show that two circulations have developed, one near 10N 44W, and the other 400 miles to the northeast, near 13N 37W. Both circulations are elongated and disorganized. Top winds were about 35 mph.

Figure 1. Current satellite image of 97L.

The forecast for 97L
Wind shear is expected to remain in the moderate 15-20 knot range the next three days, and waters will remain warm, 28-29°C. This should allow 97L to come close to tropical depression status two days from now. The fact that there are two circulations competing for the same energy and moisture will slow down development. The larger circulation near 13N 37W will probably become the dominant one. The UKMET and NOGAPS models develop 97L into a tropical depression by Tuesday. NHC is giving 97L a medium (20-50% chance) of developing into a tropical depression by Monday. The storm is expected to track to the northwest over the open Atlantic, and shouldn't affect any land areas. By Wednesday, most of the models are predicting that an extratropical storm will form just north of Puerto Rico, and this storm will probably weaken 97L by bringing high wind shear.

Elsewhere in the Atlantic
Most of the models continue to forecast the possible development of a tropical depression in the south central Caribbean, off the coast of Nicaragua, 5-7 days from now. I put the odds of a tropical storm forming in the Caribbean next week at 30%. The potential motion of such a storm is difficult to predict at this time.

Hurricane Norbert pounds Baja
Hurricane Norbert has made landfall on the west coast of Mexico's Baja Peninsula. Norbert was briefly a Category 3 hurricane this morning, but high wind shear has stretched the storm and opened up the eye, weakening Norbert to an upper-end Category 2 hurricane with 105 mph winds. Given that no Category 3 hurricane has hit the west coast of Baja since record keeping began in 1949, Norbert may be the strongest hurricane on record to hit the west coast of Baja (two Category 3 hurricanes have hit the east coast of Baja). Exceptionally warm water temperatures of 1-3°C above average helped Norbert remain strong right up until landfall.

Crossing rugged Baja will probably knock Norbert down a full Category, by about 20-25 mph. The storm will still be a Category 1 hurricane when it makes it second landfall on mainland Mexico north of Los Mochis. The Hurricane Hunters are scheduled to fly into Norbert this afternoon to see how intense this second Mexican landfall will be. Rainfall amounts in mainland Mexico will be 4-8 inches, and 6-10 inches over Baja. Norbert's remains should bring 1-2 inches of rain to portions of western Texas and southeastern New Mexico. Since Norbert is so strong and fast-moving, it may be able to carry an unusual amount of moisture deep into the Midwestern U.S. by Monday. This could lead to flooding problems in Kansas and surrounding states early next week. A similar situation occurred in 1983, when Category 4 Hurricane Tico hit Mexico. Moisture from Tico would up in Oklahoma, where up to 16 inches of rain fell (Figure 2). The resulting flooding caused about $100 million in damage. The latest 5-day rain forecast from NOAA's Hydrometeorological Prediction Center (Figure 3) shows that the moisture from Norbert is expected to trigger heavy rains of up to three inches over Kansas and Nebraska over the next five days. This is probably an underestimate, and rainfall amounts in the 4-6 inch range are likely over Kansas and Nebraska over the coming week.

Links to follow:
Mexican radar
Loreto, Mexico weather
Santa Rosalia, Mexico weather

Figure 2. Total rain amounts from Hurricane Tico of 1983. Image credit: NOAA.

Figure 3. Forecast rain amounts for the five-day period ending Thursday, October 16, 2008. Image credit: NOAA/HPC.

Odile dumping heavy rains on Mexico
Mexico has another storm to be concerned with, Tropical Storm Odile. Satellite estimates indicate Odile has dumped up to six inches of rain on the coast just east of Acapulco. Additional heavy rains of up to eight inches should affect the coast as Odile tracks along the coast, just offshore. The storm's location and intensity are difficult to gauge via infrared satellite loops, and we'll have to wait until the Hurricane Hunters arrive this afternoon before we have a good idea of Odile's strength. Odile is under about 10-15 knots of wind shear, and this shear is forecast to remain in the 15-20 knot range the next 3-5 days. This should allow the storm to gradually intensify into a Category 1 hurricane.

Saturday update on Hurricane Ike relief efforts
I got this very nice email yesterday, giving appreciation for all those who helped out through the portlight.org Hurricane Ike charity effort:

I just wanted to express my sincere gratitude, on behalf of the City of Houston, the Mayor, and our community partners over at TIRR/Memorial Hermann, for all of your involvement in bringing medical supplies and equipment together to help Texans with disabilities affected by Hurricane Ike. I can't tell you how much we all appreciate the fact that you so quickly mobilized and leveraged such a tremendous amount of support to bring these needed items to Houston and other Texas cities.

An email simply doesn't do justice to the generous spirit and initiative that you, Paul Timmons, and your partners took to make this happen, nor to our gratitude. However, I just want you to know that we think about you all in appreciation every single day over here, and there are many who are directly benefiting from your generosity.

By the way, Paul Timmons mentioned that it looks like another shipment of 30-50 wheelchairs can be sent over here. All I can say is wow! Thank you for not forgetting about us, and for realizing that we still have a lot of needs here that we are trying to meet - even 4 weeks after the hurricane.

Again, please accept my sincere thanks. I hope that you have a wonderful

Michelle Colvard, MPH
Executive Director
Mayor's Office for People with Disabilities

Contributions to this highly worthy portlight.org charity fund are fully tax-deductible, and will go to provide relief supplies for those smaller communities typically bypassed by the traditional relief efforts. More details can be found at StormJunkie's blog.

Jeff Masters

The views of the author are his/her own and do not necessarily represent the position of The Weather Company or its parent, IBM.