As a frontal boundary moved through the area today, with a weak low pressure developing along the front, areas of light to moderate rain affected the area through much of the day, with a general 1/4 inch of rain, locally up to 1/2 inch. The rain has moved out, with a cooler air mass gradually reaching the region. While the pattern aloft remains amplified and active, the surface conditions in the region will remain relatively inactive compared with the beginning of the month, at least for the shorter range. With a strong ridge over the western US, a series of mid level shortwaves will dive southeast into the region with deep amplification expected, but in both cases on Thursday and Saturday will fail to result in more than isolated snow showers in the area, as with a progressive pattern and a lack of downstream blocking, the shortwave troughs are unable to turn negative and consolidate in time to lead to more significant impacts in the region, developing too late to do so, and in Thursdays case, the trough is too elongated and too far south to lead to precipitation in the area. High temperatures will remain in the upper 30s to mid 40s range through Friday.
By Saturday into Monday, temperatures will cool down back into the low-mid 30s for highs as the trough axis shifts into the region for a short period of time, with 850mb temperatures near -10C to -15C but falling far short of the near -25 to -30C temps observed during last week’s arctic cold outbreak, during which Central Park set a record low temperature of 4 degrees, a very rare event in recent years when far more warmth records have been broken. A moderation in temperatures back into the 40s is likely towards mid next week, but the recent warmer temperatures are expected to remain only temporary, however, as persistent northeast Pacific ridging and potential transient ridging near Greenland suggest a return to more winter-like conditions for the last 10 days of the month into early February. More information on the long range will be posted with the next full forecast update on Friday night.