June 14, 2012: Heat Possible Late Next Week

Forecast Highlights:


- Seasonable Weather Through Tuesday
- Heat Potential Late Next Week; 95-100 degrees possible


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Today's Observations:

With yesterday's storm having moved out of the region, a high pressure moved in, bringing dry conditions again. More cloud cover was observed than originally expected, although temperatures were close to the forecast, reaching the lower to mid 70s in Long Island/S CT and the mid 70s to 80 degrees from NYC and further north/west.

This high pressure will stay in place through next week, providing the area with mostly to partly sunny skies and seasonable temperatures. By Wednesday, however, a large ridge in the central US will begin to spread east, resulting in the potential of the first heat wave of the year for the region.


Friday - Tuesday: Seasonable, Dry, Mostly Sunny


As mentioned with yesterday's discussion, with the high pressure in place, little variation is expected in the outlook. The main highlight will be an onshore flow during the weekend, with more cloud cover and lower temperatures near the coast, where highs will likely reach the upper 60s to lower 70s for most of Long Island/S CT while interior areas reach at least the mid 70s. Otherwise, mostly sunny skies will continue with highs in the lower to mid 70s in Long Island/S CT and the mid 70s to lower 80s from NYC and further north/west, with low 80s likely especially on Friday.


Wednesday - Next Weekend: Heat Wave Potential


Up until this point, there have been few heat spells in the region due to lasting influence from back door cold fronts in part due to a blocking pattern near Greenland, and an unfavorable ridge axis for heat, which sends the heat from the central US into Canada. By the middle of next week, another surge of heat will move into the central US, but with the high pressure shifting east without anything to completely push the heat into Canada, the heat is likely to move into the region for the first time since late May.

At this time, most of the models support the heat potential, with the ECM and the GFS bringing 850mb temperatures to 20C, which in typical summer heat waves would result in highs in the upper 90s to low 100s and is supported by this type of air mass that is modeled for the late week. The CMC keeps the heat mostly to the west, but has an offshore upper level low closer to the coast than the rest of the guidance. The 12z ECM also shows a back door cold front moving through on Thursday; while the possibility is there that a back door cold front comes through, with this set up it is unlikely to advance much south of New England, and even if one does come through at least a brief period of heat would still affect the region.

Although due to the time range, the specifics are still uncertain, there is an increasing probability of temperatures passing 90-95 degrees in parts of the region, including the area, on Wednesday, Thursday and possibly Friday. Should the warmest case scenario verify, with no back door cold front and 850mb temps near 20-22C, which is a reasonable possibility, temperatures may get as high as the upper 90s to even 100 degrees, although this part is still only a possibility and depends on the amount of sunshine, wind direction and where any back door cold front ends up. Stay tuned for more information on the heat spell.