Thunderstorms

The National Weather Service is calling for Friday to be mostly cloudy in the Baltimore area, with a high near 94 and winds becoming westerly between 4 and 7 miles per hour. There is a 70 percent chance of precipitation, most likely after 1 p.m. Forecasters warn that some afternoon and early evening thunderstorms may be severe with damaging wind gusts. Friday night is expected to be cloudy, with a low around 72 and northwest winds between 6 and 9 miles per hour. There is a 60 percent chance of precipitation, most likely before 2 a.m. Saturday is expected to start out mostly cloudy and gradually become sunny, with a high near 89 and north winds between 8 and 10 miles per hour.

The National Weather Service was calling for Wednesday to be rainy, with a high near 71 and east winds of 11 to 13 miles per hour. Rain could be heavy at times. Thunderstorms are possible after 2 p.m. New rainfall amounts of between a quarter of an inch and half an inch are possible. Wednesday night is expected to be mostly cloudy, with a low around 55 degrees and south winds of 10 to 15 miles per hour. There is a 60 percent chance of precipitation. The National Weather Service has issued a coastal flood watch for Wednesday evening and night for the western shore of the Maryland Chesapeake Bay, from Calvert County northward.

Severe thunderstorms that poured rain over Central and Western Maryland last night brought high winds and intense lightning that downed trees and cut off power to more than 18,000 residents.Carroll County had the most power failures, with about 4,500 customers affected. Baltimore County had 3,800 who lost power, Harford County had 2,600 and Howard County had 1,800, said Baltimore Gas and Electric Co. spokesman John A Metzger. By 11 p.m., 12,800 customers were still without power.The storms began moving east across the state at 7:30 p.m.In Baltimore County, a tree fell on a car at the intersection of Seminary and Francke avenues at 10:07 p.m., the Baltimore County Fire Department said.

Powerful thunderstorms rumbled across Maryland last night with high winds and at least 7,000 bolts of lightning that knocked out electrical power to thousands of homes.At Joy's Sub Shop in Glen Burnie, employees and customers were convinced they saw a tornado.Al Sadaka, who was working at his mother's sub shop on Quarterfield Road, said the wind uprooted two trees, lifted a large trash bin off the ground, shook the shop windows and ripped the letters from the restaurant's exterior about 7:30 p.m.Whether a twister had dropped in, as Mr. Sadaka suspected, could not be confirmed.

A cluster of severe thunderstorms swept across Southern Maryland last night, prompting tornado warnings by the National Weather Service that urged people to duck for cover as meteorologists traced alarming Doppler radar readings. The band of storms, which formed in Northern Virginia, left mostly flooded streets, downed trees, damaged cars and edgy residents in La Plata, who remembered the deadly tornado that generated winds exceeding 207 mph and flattened the small town a little more than year ago. The first warning was issued at 6:21 p.m., when Doppler radar indicated a developing tornado nine miles southwest of Nanjemoy in Charles County, as the volatile storm system moved east across the Virginia-Maryland border at 30 mph. The weather service office in Sterling, Va., had received several reports of funnel clouds as the storms continued on a path near La Plata, White Plains and Port Tobacco.

The National Weather Service is calling for Tuesday to be partly sunny, with a high near 76 and west winds between 6 and 9 miles per hour. There is a 30 percent chance of showers and isolated thunderstorms, which may produce gusty winds and small hail. New rainfall amounts of less than a tenth of an inch are expected, except that amounts may be higher where there are thunderstorms. A small craft advisory is in effect for portions of the Maryland Chesapeake Bay and the tidal Potomac River.

A waterspout, or tornado over water, was spotted by members of the public over the Back River near Edgemere on Sunday evening, according to the National Weather Service. The weather service said the sightings occurred about 6:40 p.m. About the same time, Doppler Radar indicated a line of thunderstorms moving through the heart of Baltimore's Inner Harbor that are capable of producing strong wind gusts and waterspouts, the weather service said in announcing a special marine warning.

CAPE CANAVERAL, Fla. - Thunderstorms prompted NASA to postpone the launch of the first of its two Mars rovers yesterday - the second delay in two days. The National Aeronautics and Space administration will try again today with a launch scheduled for 1:58 p.m. at the earliest. The weather outlook is "significantly improved," said Kennedy Space Center spokesman George Diller. The $800 million twin Mars Exploration Rovers are to reach Mars in January and begin a search for evidence of water on the planet's distant past.

Dramatic thunderstorms crossed Maryland yesterday afternoon and evening, with flashes of lightning that knocked out power to thousands of homes.In Anne Arundel County, some 3,600 customers lost power, Baltimore Gas and Electric Co. spokesman John Metzger said.The storms were touched off by a cold front moving eastward across the region, and heralding the arrival of dry Canadian air and clear skies that may last through the weekend, the National Weather Service said.Mr. Metzger said lightning disrupted service to 19,500 homes and businesses in its Central Maryland system.