Tropical Feel

Written on 08/09/2021
Jonathan Carr

Discussion: The coastal surface low cleared out yesterday for most of NJ however took it’s time leaving extreme ENJ. Some impressive rainfall totals for SENJ. Today we have an upper-level disturbance floating through but it shouldn’t produce much precipitation. Normally, the backside of a cyclonic flow is cooler and drier however we are deep within broad SW warm sector flow driven by the Bermuda high. So not much relief other than a few hours last night. This means a hot and humid Monday-Friday though with S/SW flow and likely a capped environment. This means that thunderstorms will struggle to form in general but could occur in isolated instances where enough lift can break the cap. The ECNJ/SENJ coastal areas have the best chance for this to happen during afternoon-evening hours due to sea breeze plowing inland and providing the lift. Will have to play the radar each day for any rogue pop-ups but the most realistic expectation, Monday-Friday, is hot and humid. Heat indices should push over 100, especially Wed-Fri. Monday-Tuesday are walk-ups to the heat wave. It looks like a cold front wants to come through between Friday PM and Saturday PM hours. The difference in timing could mean the difference in a nice or stormy Saturday. Given the hot and humid (storm fuel) setup this week, storms along that front could be severe. I’ll track this closely this week to best anticipate. Aso we have Fred likely to form and impact the Greater Antilles this week before possibly impacting Cuba/S Florida this weekend. The reason I’ll track Fred (currently Invest 94L) is because some longer-range model guidance suggests a close NJ pass later next week. 

Monday (Aug 9) high temperatures should reach the mid-to-upper 80s for most areas. Interior CNJ/SNJ has the best chance to hit 90. The ECNJ/SENJ coast closer to 80. Skies should be mixed with sun and clouds with a humid feel. Winds should be light out of the SW. Overnight lows should hover near-70 statewide.

Tuesday (Aug 10) high temperatures should reach near-90 for most areas. Coastal areas likely maxing in the lower-80s. Skies should be mostly sunny with a humid feel barring any isolated pop-ups. Winds should be light out of the S/SW. Overnight lows should range from near-70 to mid-70s from elevations to coasts.  

Wednesday (Aug 11) high temperatures should reach well into the 90s for most areas. Coastal areas in the mid-80s. Skies should be mostly sunny and humid yielding dangerous heat indices. Storms are generally not expected but you can’t rule out rogue pop-ups given the environment. Winds should be light out of the S/SW. Overnight lows should range from near-70 to mid-70s from elevations to coasts. 

Thursday (Aug 12) high temperatures should reach well into the 90s again for most areas. Coastal areas in the mid-80s. Skies should be mostly sunny and humid keeping dangerous heat indices on the table. Isolated-to-scattered thunderstorms are possible, especially during afternoon-evening hours. Winds should be light out of the S/SW. Overnight lows should range from near-70 to mid-70s from elevations to coasts. 

Friday (Aug 13) high temperatures should again reach well into the 90s for most and produce dangerously high heat indices. It might even near-90 on the beaches before any sea breeze fronts form in the afternoon. A cold front is expected to pass through as early as Saturday morning or as late as Saturday night. I’ll have to check back in a few days once I gain some more confidence in the storm front setup.

An early look at the weekend indicates conditions much more comfortable after the Saturday cold front comes through. Whether that cold front passes early Saturday AM or late Saturday PM is still yet TBD. But once that’s through, highs should max in the 80s with lower humidity (for Sunday, possibly Saturday if the front is through sooner. It should feel amazing after the heat that’s on-deck for this week. I’ll be tracking the NJ thunderstorm situation Friday PM-Saturday PM as well as the tropical system expected to threaten the Cuba/Southern Florida area this weekend…before possibly turning up the east coast next week. I’ll update accordingly. Have a great week, stay as cool and hydrated as possible, and please be safe! JC

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