Last Updated: 9:30am Tuesday, February 20th, 2018 by MP
Near Term (through tonight)
Strong upper-level ridging over the region will lead to some unseasonably mild temperatures by this afternoon. First low-level inversion with abundant moisture and very light winds near the surface, has been resulting widespread areas of patchy or dense fog with visibilities ¼ mile or less since the overnight hours. But as of 9am visibilities have rising in most sites. Visible satellite imagery also shows breaks in the low cloud cover. This inversion is beginning to mix out. So we anticipate more sunshine to gradually mixing with some mid-high level clouds during the late morning and afternoon hours.
There is some uncertainty with high temperatures today due to amount of cloud cover. But if there is enough sunshine, 850mb temperatures between +10 to 12 C and southwest winds will support high temperatures mid-upper 60s to perhaps around 70, away from the coast this afternoon.. Along the south-facing shores, especially over Long Island and Connecticut, more marine influence or sea-breezes will likely keep high temperatures in mid-upper 50s to lower 60s. Nevertheless these temperatures are 15 to 25 degrees above normal for this of year. Thus record highs at the climate sites are in jeopardy today.
Mild conditions continue tonight. More low clouds, and areas of fog and drizzle will being returning again with as warm-air advection increases and nocturnal inversion increases. Patchy, dense Fog with reduced visibilities ¼ mile or less is possible. But a stronger low-level southwest flow, may prevent more widespread patchy or dense fog for tonight. So we haven’t highlight this in hazards yet. Temperatures will likely hold mostly in the 50s overnight. Along south-facing shores, colder waters offshore, may lead temperatures may dropping into the 40s early this evening, before rising back into 50s, with increasing warm-air advection.