Temperatures surged into the upper 40s to mid 50s across the area today, nearly 10 degrees above average in Central Park, the first time widespread above average temperatures were observed since February 23. A brief cool down is expected tomorrow followed by even warmer temperatures for Monday and Tuesday, likely reaching the mid-upper 50s near NYC, before returning back to below average on Wednesday and Thursday as a storm system affects the region with rain and possibly snow.
Tonight – Tuesday: Brief Cool Down, Then Warm Again
Posted above from left to right are the latest available surface analysis and radar composite from WPC, and the initialized GFS 500 millibar heights and vorticity from NCEP MAG; both are valid at 18z (1pm). The coastal low which affected the Mid Atlantic region with coastal rain and high elevation snow/ice has since moved offshore; the system was primarily driven by the southern stream, with virtually no interaction with the northern stream. With this lack of connection, the northern cold front lagged behind the coastal low, only moving through the region this afternoon. This delayed timing allowed for a warmer air mass aloft to advect into the region, with a downsloping westerly flow allowing for much warmer temperatures this afternoon, generally peaking in the low-mid 50s with temperatures as warm as 59 degrees in Newark, NJ and 57 degrees in Central Park. This marks the first time temperatures were above average in Central Park since February 23, ending a 12 day consecutive streak of below average temperatures, tied with December 7-18 as the longest period of below average temperatures this winter.
As the cold front continues to progress offshore, another cold air mass will enter the region tonight into Sunday. This will set up for continued partly to mostly cloudy skies on Sunday but with highs in the 35-42 degree range, coldest in interior NW areas and warmest near NYC, with a NW wind at 8-15 mph. More significant warming is expected in the early week, however, as a strong jet streak currently entering the NW US and southwestern Canada continues to rapidly progress eastward, cutting off a trough in the southwestern US and setting up for a relatively zonal flow over the northern US. Meanwhile, as a relatively weak area of low pressure over southern Canada rapidly tracks eastward north of the region, a warm air mass will be advected into the region again. After a period of scattered rain/snow showers on Monday morning, partly to mostly cloudy skies are expected with highs rising into the mid 40s to low 50s. Warmer temperatures are expected on Tuesday as a cold front slowly approaches the region, with partly cloudy skies and highs expected to reach the low to mid 50s, with the possibility for upper 50s near NYC and NE NJ.