FXUS64 KCRP 182042 AFDCRP Area Forecast Discussion National Weather Service Corpus Christi TX 342 PM CDT Sun Apr 18 2021 .SHORT TERM (Tonight through Monday Night)... Anticipate that synoptic-scale lift, associated with an approaching upper level disturbance, from both 700-300mb q-vector convergence and the position of the subtropical jet streak (deterministic output), will combine with near normal PWAT values (NAM/GFS deterministic output), to generate at least isolated showers (thermodynamics per the NAM not favorable for thunderstorms) over the southern Coastal Plains/Waters Monday. Cool again tonight, with low temperatures generally from the upper 40s to mid 50s, highs Monday in the 70s, and slightly warmer Monday night, similar to SREF mean values/NBM. && .LONG TERM (Tuesday through Sunday)... Synoptical conditions will be quiet to start off the long term period. An upper low in Canada will result in weak troughing for the Central CONUS followed by zonal flow for South Texas midweek. A mid-level low develops off the coast of California Thursday and dives south over the Desert SW before trekking east across Northern Mexico and arriving in TX Saturday. Tuesday will be dry and not expecting showers as PWAT's are below 1 inch and low level moisture is lacking. A cold front will pass through Tuesday night resulting in a wind change and slightly coolers temps for Wednesday, then retreats back north as a warm front Thursday. Tight gradients and a high developing out over the Gulf will result in moisture advection as strong onshore flow returns Wednesday night. This will help to erode the cap and re- introduce shower and thunder possibilities for Friday into Saturday. Moisture profile will be above normal and the GFS still has PWAT's around 1.90" which is near the 99th percentile but is still the wetter solution. If this trends lower may have to adjust PoP's so will keep an eye on this. As the aforementioned low approaches, a couple of shortwaves ejecting could help enhance any storms that form and could help overcome minimal CIN that's baked in on Saturday. Generally CAPE is around 1500 J/kg which is not great, but will be enough if there's no cap in place. Finally, a cold front Saturday will move through the CWA with a more west to eastward progression and will usher in warmer and drier conditions for Sunday. Thunder is not likely Saturday afternoon as a strong cap quickly builds back in with the front. Finally, P-ETSS and ETSS guidance has us fall below criteria but Coastal flooding is not out of the question as persistent northeasterly flow is expected to be near strong levels on Wednesday and water could flood beach roads and reach the dunes. && .MARINE... Will allow the Small Craft Advisory for the offshore waters to expire at 21z. Expect the combination of increasing moisture and upper forcing to contribute to an increasing chance for isolated showers Monday. Weak to moderate east to northeast flow continues through Tuesday night until a dry cold front early Wednesday morning ushers in a period of moderate to strong northeast winds with Small Craft Advisory conditions possible. This flow will become moderate by late Wednesday while turning onshore and continuing through late week. Onshore winds could become strong at times from Thursday through Friday. Isolated to scattered showers and thunderstorms may develop Thursday night and Friday ahead of an upper level disturbance. && .PRELIMINARY POINT TEMPS/POPS... Corpus Christi 53 72 57 81 55 / 10 20 10 10 0 Victoria 49 74 54 82 49 / 10 10 0 10 0 Laredo 54 76 57 87 57 / 0 10 0 0 10 Alice 50 75 54 86 54 / 10 10 10 10 0 Rockport 57 75 60 80 55 / 10 20 10 10 0 Cotulla 51 78 54 89 52 / 0 10 0 0 0 Kingsville 51 73 55 83 55 / 10 20 10 10 0 Navy Corpus 60 71 62 76 59 / 10 20 10 10 0 && .CRP WATCHES/WARNINGS/ADVISORIES... TX...None. GM...Small Craft Advisory until 4 PM CDT this afternoon For the following zones: Waters from Baffin Bay to Port Aransas from 20 to 60 NM...Waters from Port Aransas to Matagorda Ship Channel from 20 to 60 NM. && $$ WC/87...SHORT TERM BF/80...LONG TERM