Tag Archives: extratropical storm

NYC Weather Update – May 18, 2020

While it looked earlier this weekend that this would be a rainy week, it now appears that strong high pressure will keep two storm systems largely at bay. One of these will be the post-tropical remnants of Tropical Storm Arthur that formed this weekend. The tradeoff is that this high of Canadian origin will bring cooler than normal temperatures in the 60s. This pattern breaks up by late this week, yielding warmer temperatures in the 70s by this weekend.

Rest of today – mostly cloudy though no rain expected with high temperatures around 70ºF. Clouds from the two storm systems below will remain throughout the day. Overnight lows in the mid-50s as skies gradually clear.

In this GOES geocolor visible satellite loop, you can clearly see two centers of circulation – one over the Midwest associated with a maturing mid-latitude cyclone, and one over the Atlantic – Tropical Storm Arthur.
Weather Prediction Center surface forecast for 8AM Tuesday.

Tuesday – high pressure continues building, and blocks the northward and northeastward progress of both storms. Temperatures cool into the mid-60s despite more sun with northeasterly onshore winds. Tropical Storm Arthur is expected to have undergone extratropical transition by this point, and potentially strengthened due to baroclinic forcing. The proximity of this storm to the high pressure will produce a tight pressure gradient resulting in stronger winds during the day Tuesday. Overnight around 50ºF.

Wednesday – high pressure remains in place, producing sunny skies. High temperatures still cooler than normal in the mid-60s. Overnight lows in the mid-40s.

Climate Prediction Center temperature outlook for May 23-27: temperatures appear ready to rebound going into this weekend to above normal levels.

Thursday sunny with high temperatures in the mid-60s still. Overnight lows in the low-50s.