April 3, 2013: Pattern Gradually Trending Warmer

Forecast Highlights:

The strong trough over the region producing cold and windy conditions is likely the last strong cool down of this magnitude as the pattern begins to gradually trend warmer afterwards, with temperatures climbing to warmer than average passing 60 degrees, but with increased storminess possible especially towards the middle of next week.

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Today - Saturday: Warming Up

Today is the last day of the strong cold air mass over the region as the trough weakens tomorrow with a SW flow developing, resulting in warmer temperatures reaching the low to mid 50s across the area. A coastal low pressure will develop on Friday but will remain south and east of the area, with the main impacts increased cloud cover and scattered showers south/east of NYC, especially before the afternoon hours. Due to influence from the clouds and potential rain, temperatures will be coolest south and east of NYC, in the upper 40s to low 50s, with highs in the mid 50s north and west of NYC. This coastal low was initially modeled to affect the area, but has since trended south, especially on the GFS and the NAM, with the latter as usual a significant long range outlier with the handling of this storm. Mostly sunny skies are expected for Saturday with highs in the upper 40s to low 50s east of NYC and the low 50s from NYC and further west.


Next Week: Warmer, Potentially Stormy

Towards Saturday, a widespread upper level block, not nearly to the magnitude of the mid March blocking though, is expected to drift west through Greenland and northern Canada. Unlike the March blocking, however, in this time period a zonal flow is expected to persist over the US, which will prevent the displaced cold from dropping into the region. Towards early-mid next week, lower heights are expected towards the western US as a low pressure develops towards the central US, resulting in ridging across the eastern half of the US with a widespread warm and moist air mass, which will also contribute to a potential severe weather outbreak in the central US around this time frame.

One of several uncertainties at this time is where the frontal boundary sets up in the eastern US, with the area likely to be either near or south of the frontal boundary, making the difference between highs in the 60s with partial sunshine and a risk of shower activity, and more frequent overcast conditions with some rain and cooler temperatures. Warming temperatures are expected on Sunday and Monday, reaching the mid to possibly upper 50s on Sunday and the low to mid 60s on Monday, but with increasing uncertainty towards Tuesday and the mid week depending on how far south the frontal boundary shifts following a likely wave of low pressure in the Great Lakes and northern Northeast region on Monday night. At this time, I sided with a slower southward shift of the cold front, with highs sticking around in the 60s through mid-late next week, potentially a bit cooler at times, until the storminess in the central US potentially shifts into the region, although this part of the outlook is still subject to change. Stay tuned for more information on the longer range outlook.