Winter Storm — Monroe, Pennsylvania

1999-01-13 to 1999-01-15 · Monroe, Pennsylvania

Wider weather episode

A very protracted winter storm affected Eastern Pennsylvania from the 13th through the 15th. A combination of snow, sleet and heavy freezing rain fell across the region. Some heavy rain even fell across Delaware and Philadelphia Counties. About 10,000 homes and businesses lost power throughout the area, most in Berks County. Eastern Pennsylvania was fortunate that a large enough portion of the precipitation fell as snow and sleet and not freezing rain. The water equivalent of frozen precipitation (snow, sleet and/or freezing rain) was around 1.25 inches. The highest reported accrual of ice were around half an inch. Philadelphia and most of Delaware County escaped further damage as the temperatures rose above the freezing mark just as the heavy rain moved in. A cold front moved through the state the afternoon and evening of the 13th. Extremely cold air moved south behind it. Unlike the usual pattern with cold frontal passages, precipitation occurred behind the front and slowly worked its way south from the late afternoon on the 13th into the very early morning of the 14th. Precipitation started as sleet and snow in the Poconos, but started as either freezing rain or sleet farther south. Amounts through daybreak on the 14th were very light, generally just a few hundredths of an inch. A weak low pressure system developed on the cold front in the Tennessee Valley on the 14th, but weakened as it moved east off the Delmarva Peninsula during the evening of the 14th. A very strong high pressure system built into northern New England on the 14th. The high moved offshore the evening of the 14th and the flow across the Middle Atlantic States became more easterly. This permitted warmer air to move into the state during the late afternoon and evening of the 14th just as a second and stronger low pressure system was getting organized over the Tennessee Valley. A secondary low formed near Norfolk during the early morning of the 15th and this not only accelerated the increase of warmer air, but also produced heavy precipitation.During the day on the 14th, the cold air became deep enough for precipitation to fall as primarily snow and sleet. During the evening of the 14th, the transition back to freezing rain started, first in Philadelphia around 7 p.m. EST and spread north into the Poconos by midnight. Enough warm air moved in to change the freezing rain to rain in Philadelphia starting at 4 a.m. EST on the 15th, just as the heavy precipitation moved in. The change to plain rain occurred around 7 a.m. EST in the Lehigh Valley and around 9 a.m. EST in the Poconos. Precipitation changed back to snow as it ended in the Poconos. Snow and sleet accumulations were about an inch or two from the Lehigh Valley south and from 3 to 7 inches in the Poconos. Ice accretions were generally between one quarter and half an inch; a little less within Philadelphia. Storm total amounts averaged between 1.0 and 1.7 inches for the event, most of which fell during the morning of the 15th. Where precipitation was lucky enough to change to rain, there was some poor drainage flooding, but no serious problems were reported. Most schools in Eastern Pennsylvania were closed on both the 14th and 15th. Countless vehicular accidents occurred. There were also dozens and dozens of "slip and fall" pedestrian accidents as numbers of people suffered either fractures or sprains. In Northampton County, about 2,200 homes lost power, mainly because of a vehicle that struck a utility pole. A 77-year-old man was found dead in his Lower Nazareth Township garage. It was suspected he suffered a heart attack while shoveling the snow and ice. In Berks County, 6,000 homes and businesses lost power; 900 after a sports utility vehicle slammed into a pole in Amity Township. About 2,700 homes also lost cable service. Pennsylvania State Route 662 was closed in Richmond Township because of downed wires. Numerous street lights were out in Brechnock, Cumru and Exeter Townships. Pennsylvania State Route 422 in Exeter township was described as a slow go. In Chester County, some roads were closed because of accidents. In Delaware County, emergency personnel responded to 450 calls between Midnight and 8 a.m. EST on the 15th. Malls closed early. In Bucks County, a jackknifed tractor trailer forced the closure of the southbound lanes of Interstate 95 for an hour. In Philadelphia, there were numerous "slip and fall" accidents. Schools within the city were also closed for two days.Once temperatures went above freezing, the problems did not stop. The Commodore Barry (between Gloucester and Delaware Counties) and Walt Whitman (between Camden and Philadelphia Counties) Bridges were both closed during the morning and early afternoon (respectively) of the 15th because of ice falling from overhead cables and beams. Several vehicles suffered cracked windshields and/or dents. The two outside lanes of the Ben Franklin Bridge were also closed. Some of the worst driving conditions in the Philadelphia northwest suburbs occurred during the evening of the 15th after the rain and above freezing temperatures had washed away the salt. Temperatures dropped below freezing and standing water turned to black ice. Chester County (150 accidents in three hours) issued an advisory warning motorists to stay home.Snow and sleet accumulations for the entire event included 6.5 inches in Long Pond (Monroe County), 3 inches in Lehighton (Carbon County) and East Stroudsburg (Monroe County). Most others were two inches or less. Event total water equivalents included 1.72 inches in Springtown (Bucks County), 1.70 inches in Long Pond (Monroe County), 1.67 inches in Valley Forge (Chester/Montgomery County Line), 1.49 inches in Lehighton (Carbon County), 1.41 inches in West Chester (Chester County), 1.29 inches in Palm (Montgomery County), 1.28 inches in Hamburg (Berks County), 1.20 inches in Reading (Berks County), 1.13 inches in Easton (Northampton County), 1.11 inches at the Northeast Philadelphia Airport and 0.98 inches at the Philadelphia International Airport.

Source: NOAA Storm Events Database, event_id 5685293. Narrative written by the NWS forecast office that issued the report.