For the last few days, Ophelia has hovered just off of the central east coast of Florida as a result of steering currents remaining weak. The system began as a tropical depression (TD #16) on the 6th of September 2005 over the northwestern Bahamas. Ophelia moved slowly northward at first and became a minimal tropical storm in the early morning hours of the 7th (local time), before stalling about 70 miles east of Cape Canaveral, Florida. Ophelia gradually strengthened into a Category 1 hurricane on the 8th but subsequently weaked back into a tropical storm on the 9th. The intensity has remained close to a minimal hurricane. The system resides over warm waters, but the storms own circulation can stir up cooler water and inhibit its growth.

The Tropical Rainfall Measuring Mission (or TRMM) satellite provides valuable images and information on hurricanes and tropical cyclones over the Tropics. TRMM captured these images of Ophelia at 15:22 UTC (11:22 am EDT) on 9 September 2005 as the storm was positioned east of the Florida coastline. The first image shows the horizontal distribution of rain within the storm (top down view) as revealed by TRMM's sensors. Rain rates in the inner swath are from the TRMM Precipitation Radar (PR), the only radar capable of measuring rainfall from space. The PR can also provide details on a storm's the vertical structure. Rain rates in the outer swath are from the TRMM Microwave Imager (TMI). The rainfall pattern is overlaid on infrared (IR) data from the TRMM Visible Infrared Scanner (VIRS). TRMM shows that Ophelia has not yet formed a complete eye. A large rain band wraps around north and west of the center with areas of embedded heavy rain (dark reds). The curvature of this rain band indicates that Ophelia has developed a good circulation pattern, but it is not particularly strong. At the time of the image, Ophelia was a strong tropical storm with maximum sustained winds reported at 55 knots (63 mph) by the National Hurricane Center.

The second image was taken at the same time and shows the height of the precipitation columns within Ophelia (as defined by the 15 dBZ isosurface). It shows that the heavy rain west of the center in the previous image is associated with higher storm tops as denoted by the area of taller red towers. Some of the towers exceed 15 km high and can be a sign of future strengthening.

TRMM is a joint mission between NASA and the Japan Aerospace Exploration Agency (JAXA).

Images produced by Hal Pierce (SSAI/NASA GSFC) and caption by Steve Lang (SSAI/NASA GSFC).