Update from Jeff Lindner:
Increasing chances of showers and thunderstorms this evening into Tuesday morning.
A slow moving frontal boundary will approach from the north today, while a weak diffuse boundary over the NW Gulf of Mexico backs northward toward the I-10 corridor. Fog and low clouds will slowly lift and break through the morning hours allowing solar insolation to push temperatures into the low to mid 80’s by mid afternoon. Air mass will become increasingly unstable through the afternoon hours as the weak front approaches from the north. Additionally, a weak upper level disturbance will move out of NC MX and across SC TX this afternoon and into SE TX this evening helping to aid lift along the front.
High resolution models show thunderstorms developing along the frontal boundary either side of the I-10 corridor early to mid this evening and lingering into much of the overnight hours while moving toward Galveston Bay and eventually the coast and Gulf waters. Given the instability that will be in place, a few of these storms could become severe with large hail being the primary threat. SPC has outlooked the entire area in a “marginal” (1 out of 5) threat for severe weather. Moisture levels will also be plentiful and given the slow moving nature of the front, some heavy rainfall will be possible. Overall, think activity will progress to the east and south fast enough to keep any urban flooding concerns to a minimum. WPC does have all of the area outlooked in “marginal” risk for flash flooding. Overall rainfall amounts of .25-.75 of an inch will be possible, with isolated higher totals under any cell training of 1-3 inches in a few hours.
Front and majority of the heavier activity will move into the coastal waters Tuesday morning, but messy upper level flow out of the SW will likely maintain mid and upper level moisture stream across the top of the “cooler” air mass with lingering clouds. Another disturbance will approach late Tuesday into early Wednesday and may produce a few showers near Matagorda Bay, but will have to see exactly how much low level dry air moves into the area on Tuesday to determine if rain chances may need to be increased slightly and further northward early Wednesday.
Late week will feature a return to increasing southerly winds, warm, and muggy conditions as the next strong storm system approaches the US central plains. It appears that this system will pass well north of SE TX, but the tail end of the front may reach the area Friday into Saturday with isolated to scattered showers.
Severe Weather Outlook (Today):
Jeff Lindner
Director Hydrologic Operations Division/Meteorologist
Harris County Flood Control District
9900 Northwest Freeway | Houston, Texas 77092
346-286-4000 (main) | 346-286-4165 (direct) | 281-924-2091 (cell)
jeff.lindner@hcfcd.org | Twitter: @jefflindner1