Friday, July 8, 2005

Today was a hard down day for N43RF. Dennis has skirted the coast of Cuba for much of the morning. The storm has intensified to a major hurricane (Category 4), with top winds of around 120 kt. It is maintaining this intensity despite being located just offshore the southern coast of Cuba. The plan for today calls includes another tasked fix/SFMR mission from N42RF, takeoff at 05 UTC, arriving in the storm at 08 UTC. We will be flying a figure-4 pattern with an IP 105 nm on the SW side of the storm. After the figure-4 is completed, 42 will turn upwind for half of a leg and then finish with a south- north leg. Drops will be released at the eyewall and center of each leg. We will also supplement the drop pattern with drops released at the 64- and 34-kt wind radii, where possible, on the SE, NE, and N legs of the pattern. N42RF would land in Jacksonville.

At takeoff for N42RF, Dennis has passed over the western portion of Cuba. It has weakened considerably, with top winds having dropped from 120 kt to 75 kt. The satellite presentation shows that the deep convection has weakened considerably, though there is an indication that the inner core remains intact. It will be interesting to see how quickly convection redevelops and Dennis reintensifies as the storm moves over the Florida Straits. The official forecast calls for Dennis to make landfall on Sunday afternoon at the western Florida panhandle.

Tomorrow N43RF is flying another research mission, taking off from San Jose at 14 UTC and arriving in the storm at about 18 UTC. We had originally planned for a combined mission with the ER-2 (takeoff 15 UTC), but there were concerns by the ER-2 crew about conditions at the airport for landings, so they pushed their takeoff earlier to 11 UTC, meaning there would be little or no coordination with the P-3. Thus little or no coordination with the ER-2 was possible. The P-3 would fly a rotating figure-4 pattern, landing in Jacksonville afterward.

With the N42RF flight tonight and the planned N43RF flight tomorrow, that makes 5 P-3 flights over a 5-day period. The plan calls for a landfall flight tomorrow with N43RF, meaning that these series of flights will have spanned the lifecycle of Dennis from immediate post-genesis, to a strong tropical storm, to a major hurricane prior to landfall, to a substantially weaker hurricane just re-emerging over water, to redevelopment over open warm waters, final landfall possibly as a redeveloped major hurricane. That will be 7 flights in 7 days. The only gap in the observations of this entire lifecycle is the lack of 12-hourly observations during the genesis and organizational phases. That was not possible, however, since N42RF was tasked to fly into Tropical Storm Cindy at the time it would have flown a 12-h mission into Dennis after the genesis stage.

Rob Rogers
HRD Field Program director