40th Anniversary of Hurricane Eloise

Hurricane Eloise satellite picture Sept. 22, 1975 (NOAA)

Hurricane Eloise satellite picture Sept. 22, 1975 (NOAA)

On the morning of September 23, 1975, Hurricane Eloise made landfall on the Florida panhandle.  A major hurricane as it struck the shore, it was the most destructive Atlantic hurricane that year.

Puerto Rican rainfall from Hurricane Eloise (NOAA/WPC)

Puerto Rican rainfall from Hurricane Eloise (NOAA/WPC)

Eloise formed from an African Easterly Wave, but did not develop a closed circulation until it had crossed more than halfway across the Atlantic.  It was monitored by Hurricane Hunters as it approached the Leeward Islands and gradually became more organized.  It did not reach tropical storm strength until it was northeast of Puerto Rico.  It dumped copious rain on that island and the neighboring Virgin Islands, with a peak total of 33.29″ (85 cm) being measure in the mountains south of San Juan.  At this time, the NOAA DC-6 and C-130 flew a boundary-layer measuring experiment into the storm, operating as low as 500 feet in parts of the storm.  During the flight Eloise reached hurricane strength, but shortly afterward it encountered the northern tip of Hispanola and dropped back to tropical storm status.

Track of Hurricane Eloise 1975 (Unisys)

Track of Hurricane Eloise 1975 (Unisys)

The NOAA planes carried out another boundary-layer experiment the following day, as Eloise’s center skirted along the northern shore of Hispanola.  The storm made the short passage over the Windward Passage and continued along Cuba’s southern shore, growing weaker and more disorganized.  It remained a weak tropical storm as it passed over the Caymans and the Yucatan Channel, encountering Cozumel late on Sept. 20th.  It turned northward over the tip of the Yucatan Peninsula and began to reorganize once it was over the Gulf of Mexico.  After regaining hurricane strength, the two NOAA planes revisited Eloise one final time, carrying out more investigations of the storm’s boundary layer.  By the time they’d left the storm, its course had shifted to the northeast, away from New Orleans and toward Pensacola.

At this point, Eloise began to accelerate forward and its central pressure deepened.  By the time it reached the Florida coast at Panama City, it was a major hurricane with maximum sustained winds estimated at 125 mph (205 km/hr).  The hurricane rapidly weakened as it moved ashore and became incorporated into a frontal zone.  Even after it became an extratropical low, it brought heavy rains to the Appalachian Mountains.  During its lifetime, Eloise caused 80 deaths, the majority in Puerto Rico due to flooding.  It also resulted in US$560 million in damage.

Some research papers by HRD/NHEML scientists resulting from Eloise:

Black, P. G., R. W. Burpee, N. M. Dorst, and W. L. Adams, 1986: Appearance of the sea surface in tropical cyclones.  Wea. Forecast., 1, 102-107.

Powell, M. D., 1980:  Evaluations of diagnostic marine boundary-layer models applied to hurricanes. Mon. Wea. Rev., 108, 757-766.

Griffith, C. G., W. L. Woodley, P. G. Grube, D. W. Martin, J. Stout, and D. N. Sikdar, 1978:  Rain Estimation from Geosynchronous Satellite Imagery—Visible and Infrared Studies.  Mon. Wea. Rev., 106, 1153–1171.

Moss, M. S., 1978:  Low-Level Turbulence Structure in the Vicinity of a Hurricane.  Mon. Wea. Rev., 106, 841–849.

Browner, S. P., W. L. Woodley, and C. G. Griffith, 1977:  Diurnal Oscillation of the Area of Cloudiness Associated with Tropical Storms. Mon. Wea. Rev., 105, 856–864.

Shapiro, L. J., 1977:  Tropical Storm Formation from Easterly Waves: A Criterion for Development.  J. Atmos. Sci., 34, 1007–1022.