Canadian high pressure provides pleasant start

High pressure over Ontario, Canada this morning will provide excellent weather conditions for the start of this work week with clear skies, low humidity, and seasonable temperatures. However, as the high pressure system shifts towards the coastal waters of New England by tomorrow afternoon, an unsettled weather pattern will take hold for the rest of the week with a marine air mass from the Atlantic ocean.

Today, high pressure will provide clear skies to scattered cloud cover throughout the Philadelphia and New York City metropolitan areas. Winds will veer from the northwest to north at around 5 mph. Temperatures will be near normal with upper 70’s to lower 80’s over the interior and New York City metropolitan area and lower to mid 80’s in the Philadelphia metropolitan area.

Tonight, the high pressure system will drift east leading to a slight increase in cloud cover. Winds will veer to the north and northeast at around 5 mph. Temperatures will vary significantly depending on location. Low temperatures in some of the secluded valleys of northeastern Pennsylvania, northwestern New Jersey, and the Hudson Valley will fall into the upper 40’s to lower 50’s while the rest of the interior and western suburbs of Philadelphia and New York City will range from the mid to upper 50’s. Low temperatures along the coast and within the New York City and Philadelphia metropolitan areas will range from the lower to mid 60’s.

Tomorrow, as high pressure shifts towards the New England coastal waters, clouds will increase through the day. An area of low pressure will approach from the Tennessee River Valley and track to the south of New Jersey and towards the coastal waters of Delaware. As a result, widely scattered to isolated showers will be a threat, especially over southern New Jersey. Winds will veer to the east at 5 to 10 mph. Temperatures will rise into the upper 70’s to lower 80’s over the northern interior, immediate coast, and New York City metropolitan areas and lower to mid 80’s over the Philadelphia metropolitan areas and the western suburbs.

With high pressure locked in over the New England coastal waters and a series of weak low pressure systems passing to the south of New Jersey, scattered to overcast cloud cover can be expected with periods of widely scattered showers. A few showers will be capable of very heavy downpours leading to localized flash flooding. Winds will remain from the east at 5 to 15 mph over the interior and 10 to 20 mph along the immediate coast through the period. Low temperatures will range from the mid to upper 50’s over the interior and lower to mid 60’s along the coast and in urban locations. High temperatures will range from the upper 70’s to lower 80’s over the northern interior, immediate coast, and New York City metropolitan areas. Meanwhile, high temperatures will rise into the lower to mid 80’s in the Philadelphia metropolitan area. Temperatures will average near to slightly below normal through the forecast period.

High pressure will build south from New England on Friday, Saturday, and Sunday leading to clear skies throughout the region. Temperatures will continue to average near to slightly below normal. Low temperatures will range from the mid to upper 50’s over the northern interior and lower to mid 60’s along the coast and in urban locations. High pressure will range from the upper 70’s to lower 80’s throughout the Philadelphia and New York City metropolitan areas.