July 4: Heat Continues, Tropics Heating Up

Today's weather for the 4th of July was unseasonably hot, and with temperatures ending up slightly warmer than expected, parts of the area even reached the lower 100s today, including JFK and Newark airports, and today is not even the hottest day of this heat wave, as even hotter temperatures are on the way for tomorrow, Tuesday and Wednesday. Afterwards, however, relief may be on the way.

Meanwhile, the tropics are starting to heat up, with two invests that may become named storms and threaten the United States over the next 1-2 weeks, and another two disturbances that aren't expected to develop yet but are worth watching. One of these invests may potentially reach the Gulf of Mexico. More details on that have been posted below.

Tomorrow's Outlook

As hot as today was, tomorrow will be even hotter. With 850 mb temperatures similar to, if not slightly warmer than today, near 20c, high temperatures are expected to be in the mid to upper 90s inland, and in the upper 90s to lower 100s for the immediate NYC area. Long Island and S CT may also reach the mid to potentially upper 90s. As with today, humid conditons are not expected, however the dew points will be slightly higher, likely near the mid to upper 50s.

The rest of the region will also be hot, with parts of, if not most of the Washington DC to NYC corridor likely to reach the lower 100s. While not as hot as the DC-NYC corridor, the rest of the Northeast will also see very warm temperatures, reaching the upper 80s to lower 90s across most of the Northeast, except for central/norther Maine which should be colder, in the lower to mid 80s.

Tuesday - Thursday: Heat Continues, Humidity Increases

Tuesday will be the hottest day of this heat wave. With 850 mb temperatures likely between 21c and 23c, high temperatures in the lower 100s should be more widespread, and while still uncertain, one run of the GFS today even showed temperatures reaching the mid 100s for parts of the DC-NYC corridor. Whether this verifies or not, Tuesday will be very hot. Combined with increasing humidity and dew points reaching the 60s, conditions will be quite uncomfortable, with the heat index reaching the lower to mid 100s.

By Wednesday, however, there are increasing differences, as the GFS and the ECM bring a back door cold front through. The 18z GFS was the most extreme in this, cooling temperatures back into the 80s, which at this time is an outlier solution. This is still uncertain, however, as today's earlier NAM runs do not show any back door cold front, and keep the heat through Wednesday and Thursday, though the latest NAM run does bring through the back door cold front. For now, I am leaning more towards the less extreme NAM but keeping an eye on the GFS/ECM, slightly cooling down Wednesday and Thursday's forecast temperatures (the latest forecast can be found in the 5-Day Forecast page), however this forecast is still subject to change.

Friday-Sunday: Rain Finally Returns

By late Friday or early Saturday, a cold front should affect the area, bringing the first chances of rain to the area since late June. The models differ with the timing and any severe weather potential, however if these solutions remain consistent, scattered showers and thunderstorms may be possible on Friday night into Saturday. Temperatures will also cool down, likely returning into the 80s by Saturday. Stay tuned for more details on this rain potential.


Atlantic Hurricane Season: Tropics Heating Up


The second official month of the Atlantic hurricane season is here, and the activity is definitely picking up. On their latest update, the NHC show 4 areas of potential tropical development. At this time, I am only following 2 of these areas, as I do not expect the others to develop into tropical cyclones at this time.

West Carribean: The first disturbance, invest 96L, is currently in the western Caribbean, and is moving northwest. The models show this reaching the northeastern Yucatan Peninsula, then moving towards the central Gulf of Mexico late this week before making landfall somewhere between northeastern Mexico and Louisiana. 96L is currently in a favorable area for development, and has a 60% chance of becoming a tropical depression or storm within the next 2-3 days.

If it does become a tropical storm, however, it should be closer to the oil spill than Alex was, and despite being weaker than Alex, it may affect the oil spill. More details on this potential will be posted over the next few days, and how it may affect the United States.

East Caribbean: The second disturbance, currently in the eastern Caribbean, currently moving WNW. This disturbance is in a favorable environment, and may become the next invest, which would be 97L, over the next few days.