As to the rain, in most of the country p/c coverage is for wind perils, not flooding which is separately insured by the federal flood insurance program.
Dangerous Hurricane Joaquin has intensified to a Category 4 storm with 130 mph winds and a 936 mb pressure, making it the strongest Atlantic hurricane in five years. The last stronger storm was Hurricane Igor of 2010, which bottomed out at 924 mb on September 15, 2010. Joaquin is now the second major hurricane of 2015 in the Atlantic, joining Hurricane Danny, which peaked as a Category 3 storm with 115 mph winds on August 21. Joaquin's motion has slowed to a 5 mph westward crawl over the Central Bahamas, which are receiving an epic pounding from the mighty hurricane. David Adams of Reuters told me this afternoon that he has been calling down to the Bahamas, and no phones are being answered on Aklins Island--but Reuters' Nassau correspondent informed him that flooding was bad on Aklins Island and Long Island. The last hurricane hunter aircraft departed the storm after a 12:47 pm EDT eye fix, and new plane will be in the storm early this evening. The Hurricane Hunters found that Joaquin's eye had shrunk from 41 miles in diameter early this morning to 27 miles in diameter this afternoon. Shrinkage of the eye is common in intensifying major hurricanes, and eyewall replacement cycles that lead to temporary weakening of the storms typically occur when the eye diameter gets down to about 10 miles. Wind shear continued to be in the moderate range, 10 - 20 knots, on Thursday afternoon, and visible and infrared satellite loops showed that Joaquin was a moderate-sized hurricane with impressive organization, with a solid core of intense eyewall thunderstorms surrounding a clear eye. Upper level wind analyses from the University of Wisconsin show that the hurricane has maintained an impressive upper-level outflow channel to the southeast, and it appeared a new outflow channel was ready to open up to the northwest, which would support continued intensification. Ocean temperatures in the region remain a record-warm 30°C (86°F), but may start to cool due to Joaquin's slow motion. This cooling of the waters could well put the brakes on further intensification by Friday morning....
...Joaquin likely to miss the U.S. Confidence is growing that Joaquin will move out to sea this weekend, although a U.S. landfall still cannot be ruled out. Among the 12Z (8 am EDT) Thursday operational runs, three models--the Canadian GEM and the U.S. GFDL and NAVGEM models—continue to call for a landfall on the U.S. East Coast. Other models, including the four that performed the best for three-day outlooks during the 2014 Atlantic hurricane season (GFS, ECMWF, HWRF, and UKMET), now agree that Joaquin will turn sharply toward the north or northeast and begin to accelerate by late Friday or Saturday, feeling the influence of an upper-level low drifting well to the northeast. The less-likely possibility of a U.S. landfall hinges on the idea that a strong upper-level trough would produce a cut-off low in the Southeast that would hook Joaquin around it, much as happened with Hurricane/Superstorm Sandy in 2012. That cut-off low is still expected to form, but the balance between the eastern U.S. low and the Atlantic low in terms of influence on Joaquin now appears to favor the latter. NHC nudged the forecast track for Joaquin further east in its 5:00 pm EDT outlook. In the associated discussion, they stressed: “We are becoming optimistic that the Carolinas and the mid-Atlantic states will avoid the direct effects from Joaquin. However, we cannot yet completely rule out direct impacts along on the east coast, and residents there should continue to follow the progress of Joaquin over the next couple of days.”...MUCH MORE
Figure 5. 5-day rainfall amounts for the period from 8:00 pm EDT Thursday, October 1, to Tuesday, October 6. Almost all of South Carolina is projected to get 10” – 20” of rain. This map assumes that Hurricane Joaquin will remain offshore from the U.S. East Coast. Image credit: NWS Weather Prediction Center.
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