Search Results

You are looking at 1 - 9 of 9 items for :

  • Atmosphere-land interactions x
  • Annual Weather Summaries in Monthly Weather Review x
  • All content x
Clear All
Mark A. Lander, Eric J. Trehubenko, and Charles P. Guard

phase) years than during La Niña (ENSO cold phase) years ( Lander 1994 ). During La Niña years, the few TCs that form east of 160°E typically form north of 20°N and are often directly associated with TUTT cells. Low-level easterly wind flow was unusually persistent in the low latitudes of the western North Pacific during June–October of 1996 ( Fig. 3 ). The normal southwest monsoon of the Philippine Sea (with its episodic extensions farther eastward) was replaced by mean monthly easterly flow

Full access
Richard J. Pasch and Lixion A. Avila

pose a potential threat to land areas. These aircraft observations are of vital importance to the tracking and forecasting of tropical cyclones and for the issuance of warnings, since aircraft provide more precise information on center location and intensity than satellites. It has been shown ( Sheets et al. 1988 ) that Dvorak intensity and location estimates can differ significantly from aircraft estimates. Table 1 lists the tropical storms and hurricanes of 1996, and Fig. 1 shows their

Full access
Michael J. Brennan, Richard D. Knabb, Michelle Mainelli, and Todd B. Kimberlain

just south-southeast of Cape Lookout, North Carolina. A few hours later, Gabrielle made landfall along the Cape Lookout National Seashore; however, strong northerly upper-level winds kept the convection and strongest surface winds offshore. Shortly after landfall, Gabrielle weakened due to the northerly wind shear and interaction with land. Gabrielle turned northeastward and exited the coast near Kill Devil Hills, North Carolina, just after 0000 UTC 10 September. After moving back over the Atlantic

Full access
James L. Franklin, Lixion A. Avila, Jack L. Beven, Miles B. Lawrence, Richard J. Pasch, and Stacy R. Stewart

that affected land were significantly weakened by hostile environmental conditions prior to landfall. There were no hurricane landfalls in the continental United States, but both Gordon and Helene came ashore in northern Florida as tropical storms. Only twice before (in 1951 and 1990) have there been as many as eight hurricanes in a season with no U.S. hurricane landfalls. Total U.S. damage for the season is estimated to be a modest $27 million. However, this does not include roughly $950 million

Full access
Lixion A. Avila and Jamie Rhome

, at about 2100 UTC 4 September with maximum winds near 70 kt. Figure 5 depicts Hurricane Henriette just prior to making landfall in Baja California. Continuing north-northwestward, Henriette emerged over the Gulf of California early on 5 September. The interaction with land caused a slight weakening, but Henriette remained a category 1 hurricane for most of that day. Very late on 5 September, however, Henriette began to weaken. It made its final landfall along the Gulf of California coast of

Full access
Lixion A. Avila, Richard J. Pasch, John L. Beven II, James L. Franklin, Miles B. Lawrence, and Stacy R. Stewart

of Mexico from Punta Maldonado to Zihuatanejo at 1500 UTC 12 October and upgraded this watch to a tropical storm warning for the same area 6 h later. Radar images indicated that the center passed just to the south of Acapulco around 0400 UTC 13 October. The tropical storm warning was extended westward to Lazaro Cardenas at 0900 UTC 13 October. The interaction with land, and the influence of a larger low-level cyclonic circulation to the southwest, appeared to have disrupted the tropical cyclone

Full access
James L. Franklin and Daniel P. Brown

other atmospheric factors (e.g., relatively low shear) were conducive to an active hurricane season, the unexpected development of an El Niño event during the late summer appeared to suppress activity. Although the El Niño did not strongly affect the vertical wind shear throughout the basin, it likely caused or reinforced a strong area of anomalous subsidence over the western part of the Atlantic basin ( Fig. 2 ). This sinking led to a warmer, drier, and more stable atmosphere that likely limited

Full access
John L. Beven II, Lixion A. Avila, Eric S. Blake, Daniel P. Brown, James L. Franklin, Richard D. Knabb, Richard J. Pasch, Jamie R. Rhome, and Stacy R. Stewart

–Mississippi border at 1445 UTC with an estimated intensity of 105 kt (category 3). Katrina’s weakening during the last 18 h or so before the first Gulf Coast landfall was primarily due to the deterioration of the inner eyewall and the partial development of a new outer eyewall. Additional possible factors include entrainment of dry air over the western semicircle, gradually increasing wind shear, slightly lower SSTs, and (following the first Gulf landfall) interaction with land. Extensive investigation is

Full access
Lixion A. Avila, Richard J. Pasch, Jack L. Beven, James L. Franklin, Miles B. Lawrence, Stacy R. Stewart, and Jiann-Gwo Jiing

when a TC is a threat to land, such as in the cases of Hurricane Juliette and Tropical Storm Lorena of 2001. The primary data source, however, is imagery from the Geostationary Operational Environmental Satellites (GOES) and polar-orbiting weather satellite imagery, from which position and intensity estimates are obtained using the Dvorak (1984) technique. A recent study by Brown and Franklin (2002) indicates that nearly half of Dvorak satellite-based intensity estimates fall within 7 kt of

Full access