####018004745#### FXUS62 KMFL 251615 AFDMFL Area Forecast Discussion National Weather Service Miami FL 1215 PM EDT Thu Apr 25 2024 ...New SHORT TERM, MARINE, BEACH... .SHORT TERM... (This afternoon through Friday) Issued at 1214 PM EDT Thu Apr 25 2024 Models show high pressure/mid level ridging dominating the weather pattern across the region. The ridge gradually shifts eastward through the weekend with overall subsidence and dry conditions prevailing. Afternoon temperatures will again range from the lower 80s near the east coast to the mid to upper 80s over interior areas. An isolated shower or two can't be totally ruled out over the interior this afternoon, mainly along sea breeze boundaries, but chances remain very low. Given the light flow and dry airmass, another seasonably cool night can be expected tonight with lows generally in the 60s. Reinforcing high pressure is seen in models arriving on Friday, which will increase pressure gradients across Soflo. This will result in increasing easterly winds and thus a weakening of the Gulf breeze circulation. Temperatures will remain similar over the east coast (although dewpoints will slightly increase), but slightly increase over the western half of the area, but should remain seasonable overall. Given the continued influence of mid-lvl ridging, rainfall is once again not expected. && .LONG TERM... (Friday night through Wednesday) Issued at 141 AM EDT Thu Apr 25 2024 Mid-lvl ridging will establish itself over the eastern CONUS this weekend into early next week, displacing the storm track well north of the area. At the surface (initially strong) high pressure over the western Atlantic will be the main feature of interest supporting breezy easterly winds through the period, although the high will gradually be weakening into next week. Generally dry conditions will prevail given the influence of the ridge, although some shallow coastal convergence generated showers can't be ruled out over the east coast and Atlantic waters. Temperatures will be characteristic of a strong easterly regime with the warmest highs (generally upper 80s) over the Interior/west coast with cooler highs (generally low to mid 80s) over the east coast. The reverse will be true with overnight lows with milder readings (low 70s) over the east coast and 60s over the Interior/west coast. && .AVIATION... (12Z TAFS) Issued at 717 AM EDT Thu Apr 25 2024 VFR conditions will continue at all terminals during the next 24 hours. Light/vrb winds will shift east around 10-12kt after 15Z, then light/vrb again tonight. && .MARINE... Issued at 1214 PM EDT Thu Apr 25 2024 Current benign boating conditions will continue tonight as the moderate easterly winds become light and variable. Then on Friday, winds will increase and remain breezy through the weekend as strong high pressure north of the area builds southward. && .BEACHES... Issued at 1214 PM EDT Thu Apr 25 2024 A high risk of rip currents remains in effect for the Palm Beach coastline, and it is expected to expand into the rest of the Atlantic beaches this afternoon and through the weekend as easterly flow increases. && .FIRE WEATHER... Issued at 141 AM EDT Thu Apr 25 2024 The dry airmass will remain in place through the end of the week over portions of Interior and SW Florida as generally easterly flow continues to prevail. Minimum RHs below 40% can be expected over these portions of the area through Friday, with localized values approaching 35% this afternoon. Although fuels will remain dry (the Significant Fire Potential Forecast remains in the orange category), winds should remain below fire weather headline criteria through the period. && .PRELIMINARY POINT TEMPS/POPS... Miami 70 82 73 81 / 0 0 0 0 West Kendall 65 83 69 82 / 0 0 0 10 Opa-Locka 68 83 70 82 / 0 0 0 0 Homestead 68 82 70 82 / 10 0 10 10 Fort Lauderdale 70 80 72 80 / 0 0 0 10 N Ft Lauderdale 70 81 72 81 / 0 0 0 10 Pembroke Pines 69 84 71 83 / 0 0 0 0 West Palm Beach 68 81 70 81 / 0 0 0 0 Boca Raton 69 82 71 82 / 0 0 0 10 Naples 67 88 68 87 / 0 0 0 0 && .MFL WATCHES/WARNINGS/ADVISORIES... FL...High Rip Current Risk through Saturday evening for FLZ168. High Rip Current Risk through Saturday evening for FLZ172-173. AM...None. GM...None. && $$ SHORT TERM/MARINE/BEACHES...17 ####018007950#### FXUS65 KVEF 251618 AFDVEF Area Forecast Discussion National Weather Service Las Vegas NV 920 AM PDT Thu Apr 25 2024 .SYNOPSIS...An area of low pressure over our region will be pushed away today by a colder system dropping down from the Pacific Northwest which will bring scattered to numerous showers and chances for thunderstorms to southern Nevada and surrounding areas on Friday. Gusty winds will also occur...especially over the western Mojave Desert. The system will exit Saturday leading to a gradual warming trend with dry conditions through the middle of next week. && .UPDATE...12Z VEF sounding depicted a relatively cool and unstable atmosphere in place behind a shortwave trough which moved through early this morning. Morning satellite imagery also depicts a small vorticity maxima over far southern Nye County that will traverse eastward today and provide some additional lift across far southern Nevada and Northwest Arizona through this afternoon. Given the cool mid level temps as low as -20C at 500mb, it won't take a lot of sunshine to start popping some weak convection. Low levels remain fairly dry as well, with DCAPE values of 700-900 j/kg, suggesting the potential for some locally gusty winds. While coverage of activity is not expected to be widespread, a few isolated to scattered showers are likely to drift off the higher terrain through the early afternoon. Morning PoP grids reflect this expectation and a grid update is not necessary at this time. Even more widespread shower and thunderstorm activity is expected for Friday. -Outler- && .SHORT TERM...through Friday night. A line of showers with isolated thunderstorms occuring over southern Mohave County this morning extending from Parker Dam up toward Kingman will slowly push toward the east and exit Mohave County shortly after sunrise. This was being driven by vorticity advection and an upper level jet exit ridge just ahead of the trough axis which could be seen on recent satellite loops. This will pull away fairly quickly today and is forecast to be over the Four Corners Region by this afternoon leaving our area under northwest flow on the back side. There will be sufficient moisture and instability for scattered showers and isolated thunderstorms over Lincoln County this afternoon and a few showers may even develop over the Spring Mountains and could move over parts of the Las Vegas Valley this afternoon. This is indicated by recent runs of the HRRR, but any impacts will be fairly minor such as brief gusty winds and light or trace rainfall amounts. More noteworthy weather is on the way Friday due to a low pressure system which could be seen on satellite loops approaching the Pacific Northwest and this will dig over southern Nevada and surrounding states Friday afternoon and evening then move away to the Four Corners late Friday night. This will produce a setup favorable for scattered to numerous showers and a few thunderstorms. The latest NBM probability of precipitation grids indicate 50-75% across much of Nye, Clark and central/northern Mohave counties and 75-95% over most of Lincoln County. General rainfall estimates of 0.10-0.25" are indicated over Nye, Clark and Mohave counties and 0.25-0.50" over the Spring Mountains and Lincoln County. Snow levels will be 7500-8000 feet and an inch or two of snow will be possible in the upper reaches of Kyle and Lee Canyons. Small hail will be a possibility with thunderstorms. Gusty winds over 40 mph will continue to impact western San Bernardino County where a Wind Advisory is in effect until 11 pm PDT Friday evening. Winds gusting over 40 mph may expand down into the Morongo Basin late Friday afternoon. The rest of the region will see general gusts 25-35 mph on Friday. High temperatures will decrease 4-5 degrees today and another 6-8 degrees for most sites on Friday which will resulting in highs in the lower 70s for Las Vegas and similar elevations in the Mojave Desert region. .LONG TERM...Saturday through next Thursday. Lingering post-frontal northwest winds will continue through the day on Saturday as a closed area of low pressure pushes eastward out of our forecast area. Gust speeds will generally remain between 25 and 35 mph, and are unlikely to warrant any wind-related headlines. Temperatures will begin to rebound on Saturday, with a 4-6 degree increase from Friday. That said, Saturday will remain below-average for this time of year... which is around 81F for Las Vegas. Temperatures will continue to increase through Tuesday as a ridge of high pressure over the southeastern Pacific rises heights over the Desert Southwest. This ridge will result in a dry northwesterly flow aloft, which is known for being conducive for shortwave passages through the southern Great Basin. Thus, afternoon breeziness cannot be ruled out each day through Tuesday. Late Tuesday into Wednesday, the flow aloft briefly becomes zonal before an approaching closed low drops heights once again. Details regarding the strength and position of this closed low are still uncertain, but a decrease in temperatures, an increase in wind speeds, and a return of chances of precipitation are likely. && .AVIATION...For Harry Reid...Relatively light (8-12 knot) south- southwesterly winds will continue through late morning when winds will pick up and become more southwesterly with 20 to 25 knot wind gusts continuing through later this evening. Winds will fall back to a more south-southwesterly direction through the overnight hours with sustained speeds around 8 to 12 knots. There is a chance that isolated showers around the higher terrain may result in variable gusty outflow winds between 18 UTC and 00 UTC. Vicinity convection is most likely to develop in the Spring Mountains to the west of KLAS or the Sheep Range to the north. Should outflow winds materialize from showers in either of these locations, their direction would likely be be somewhere in the 270 to 360 degree range. Confidence regarding whether or not these showers will make it off the higher terrain and into the terminal area is currently low. FEW to SCT low clouds will accompany these showers, but CIGS are not expected to drop below 12 kft. For the rest of southern Nevada, northwest Arizona and southeast California...8 to 12 knot southerly to southwesterly winds will continue through later this morning at KHND, KIFP, and KEED when winds will pick up with 20 to 25 knot wind gusts continuing through the evening hours. KVGT will follow a similar trend but with northwesterly winds shifting to the southwest and gusts picking up later this morning/early this afternoon. Similar to KLAS, vicinity showers in the higher terrain around the Las Vegas Valley may produce variable outflow winds that may impact KVGT and KHND during the 18Z to 00Z timeframe. KDAG will continue to favor a more westerly direction with 25 to 35 knot wind gusts continuing through the evening hours. KDAG will also see FEW to SCT clouds with bases aob 5 kft filter through the area today. KBIH will favor a northwesterly direction with 15 to 20 knot wind gusts picking up during the early afternoon hours. These northwesterly wind gusts will continue into the evening. && .SPOTTER INFORMATION STATEMENT...Spotters are encouraged to report any significant weather or impacts according to standard operating procedures. && $$ SHORT TERM...Adair LONG TERM...Varian AVIATION...Stessman For more forecast information...see us on our webpage: https://weather.gov/lasvegas or follow us on Facebook and Twitter