Sept 30 Evening: Lowered Rain Totals?

6:40 PM: It is currently 6 PM and most of the area is still dry. The winds have been increasing a little, but are still a little weaker than they were expected to be. Moderate rain is currently falling in eastern Pennsylvania in between the two areas of rain, with more heavy rain to move into those areas tonight. From eastern Virginia to eastern MD and eastern/central PA, the worst of the storm will be felt, as once the storm is over, as much as 15 inches of rain could fall in those places.

For the area, however, it is starting to appear that the heaviest rain may never get into the area as the models have been suggesting. The latest short term RUC model runs have been trending west with each run, now barely bringing 6 hours of moderate to heavy rain in NYC and only light rain for Long Island, and keeping the area dry until 2 AM. The radar supports this, as the secondary low pressure is moving further inland than thought at first.

At first, the models had the low pressure moving just offshore, being why excessive rain totals were shown for the area, but the low pressure now appears to track inland, moving just near NYC, putting the heaviest rainfall once again where it has been all day long, from eastern VA through eastern PA, with moderate-heavy rain in NYC but amounts generally up to 2-4 inches, not the 4-7 inches of rain suggested at first. It is possible that the rain ends up a little further east and NYC sees 3-5 inches, or it trends west and NYC sees only 1-2 inches, however at this time I am going in between, currently expecting 3 to 5 inches inland, 1.5 to 3.5 inches for NYC, and 1/2 to 1.5 inches for Long Island/S CT, with the lower end of that range being the RUC’s forecast totals. Stay tuned to another update around 10 PM to see whether there is any change in the thinking for the storm, especially if there is any downward or upward adjustments to the rain totals.

With the low pressure tracking near NYC, the potential for strong winds tonight is also increasing, mainly for Long Island. Had the low pressure followed the original forecast, it would’ve brought more rain and less wind, but with a further west track, less rain and more wind are in the forecast.

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