NOAA Hurricane Hunters update

At the 63rd Interdepartmental Hurricane Conference (IHC) in St. Petersburg, Florida this week, the latest results from the 2008 hurricane research program and plans for the upcoming 2009 campaign were presented by a number of scientists involved in the National Atmospheric and Oceanic Administration's (NOAA's) P-3 weather research aircraft program. NOAA flies three state-of-the art flying laboratories into hurricanes each year, and 2008 saw their second busiest season ever. The two low-altitude P-3 aircraft flew 39 missions, and the high-altitude G-IV jet flew 23 missions. A total of 1156 dropsondes and 525 expendable ocean probes were launched on these missions, with a particular emphasis on studying the interaction of the Gulf of Mexico ocean currents with Hurricane Ike and Hurricane Gustav. These interactions play a key role in rapid hurricane intensification in the Gulf of Mexico. NOAA's aircraft also caught the genesis of two hurricanes from the tropical wave stage--Dolly and Fay. These data will be used to help improve modeling studies to better forecast when a tropical wave will turn into a tropical depression, something the models aren't very good at now.

For the first time, wind data from the P-3 tail Doppler radar was sent in real time in 2008 for ingestion into an experimental computer forecast model, the WRF-ARW. There are high hopes that this data will lead to a significant improvement in short term (24-48 hour) hurricane forecasts, beginning in 2010. For this year, the testing phase of this project will continue, with the real-time Doppler radar data from both P-3s being ingested into a non-operational version of the HWRF model. The HWRF is one of the most reliable models used by the National Hurricane Center (NHC) to produce the official forecast, and is receiving a huge amount of development effort in the coming years. If the 2009 test phase goes well, the Doppler P-3 data may go into the operational version of the HWRF model as early as 2010.

NOAA jet getting major upgrades
The NOAA G-IV jet, "Gonzo", is in the process of having a tail Doppler radar installed. The protective radome has already been installed, and the guts of the radar are expected to be added later this year. By 2010, it is expected that Gonzo will have its Doppler radar operational, which should greatly increase scientists' ability to see into the heart of a hurricane, due to the lofty vantage point this radar will have (40,000 high, as opposed to the 25,000 maximum altitude of the Doppler radars on the P-3s). Gonzo has also been fitted with a special version of the Stepped Frequency Microwave Radiometer (SFMR), the extremely valuable surface wind speed instrument carried on all the Air Force C-130 and NOAA P-3 hurricane reconnaissance aircraft. Alan Goldstein of NOAA's Aircraft Operations Center reported that testing of Gonzo's SFMR during 2008 showed that the instrument performed well, and NHC will begin receiving the data during the 2009 hurricane season (but the data will probably be for internal NHC use only until more testing is performed).


Figure 1. The NOAA G-IV high altitude weather research jet, "Gonzo". Image credit: NOAA/AOC.

A new P-3 for NOAA
The other big news from the NOAA Hurricane Hunters is the addition of a new P-3, N44RF. In keeping with the theme of naming their aircraft after Jim Henson Company's Muppets characters, the new aircraft will be dubbed "Animal". The "new" P-3 was reclaimed from the "Boneyard" of disused P-3s at Tucson's Davis-Monthan Air Force Base, and "Animal" is currently being refurbished and fitted with state-of-the art weather research instrumentation. Animal is not being fitted with a Doppler radar at present, and it is expected that the aircraft will primarily fly air pollution research missions, freeing up the other P-3s (Kermit and Miss Piggy) for exclusive hurricane work during the six months of hurricane season. Crew for the new P-3 are already beginning to arrive at NOAA's Aircraft Operations Center, and it is anticipated that the new aircraft will be ready to fly in 2010.



Figure 2. Nose art from the WP-3Ds, N42RF and N43RF. Copyright © The Jim Henson Company.

Jeff Masters