Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 05/11/24


AREA FORECAST DISCUSSION
National Weather Service Wakefield VA
811 PM EDT Fri May 10 2024 .SYNOPSIS... An upper level trough will bring another round of showers and storms this afternoon into tonight. A chance for showers continues across mainly northern areas over the weekend. Dry and warmer weather to start next week before another round of showers and storms are possible Tuesday and Wednesday. && .NEAR TERM /UNTIL 6 AM SATURDAY MORNING/... As of 810 PM EDT Friday... Low pressure was located off the NC coast this evening with an upper level trough slowly pivoting through the local area. With the loss of diurnal instability, thunderstorms have ended with scattered showers lingering across much of the area. Expect this activity to gradually taper off as it moves E over the next several hours. Temps as of 7:50 PM ranged from the low-mid 50s N to the lower 60s S. Latest observations from the Space Prediction Center show that we are currently in a G5 geomagnetic storm (Kp 9). This is the strongest geomagnetic storm since October 2003! It is the strongest level of geomagnetic storm and (if clear skies allow) this level of storm can actually be seen across VA/MD/NC and potentially farther S! Now for the bad news...given the upper level trough overhead, widespread cloud cover looks to stick around through the night across essentially the whole CWA. The best chance for some partial clearing tonight is across far SW portions of the local area. The lowest chance for clearing is across central and eastern portions of the FA. && .SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY NIGHT/... As of 230pm EDT Friday... Much of Saturday into early afternoon should stay dry as a weak upper disturbance currently over the western Great Lakes approaches the area. Models are trending slightly slower with the precipitation, with the best chances for rain across the far NW starting late Sat afternoon, then spreading east during the evening. Best chances will be across the northern half of the forecast area due to the best energy staying well north of the region. The upper low and associated surface reflection will be slow to move out on Sunday, with wrap around showers possible across mainly eastern Virginia and the lower MD eastern shore. Models are not terribly aggressive with precipitation on Sunday, so many places will likely be dry. Trough exits offshore by Sunday evening with dry weather expected Sunday night. && .LONG TERM /MONDAY THROUGH FRIDAY/... As of 230 PM EDT Friday... Overall, the extended will be seasonable although there will be rain chances throughout the week. Monday will be the only day of the week with no chances for rain with ridging aloft and at the surface. Rain chances increase for Tuesday and especially on Wednesday as the closed low currently over the SW states moves east and impacts the region. Does not look like heavy rainfall as there will not be an opportunity to tap into Gulf of Mexico moisture, but most areas should see a quarter to a half an inch of rain. Weak ridging builds in on Thursday which may allow for a dry day. Will hold onto 20 PoPs in case of an afternoon/evening shower or storm. Another better chance for rain on Friday as the consensus LREF suggest another southern stream wave moving into the area from the west. Temperatures will be seasonable for this time of year. Due to the general zonal flow across the area, am not expecting significant day to day changes in the temps next week. Highs mostly in the mid 70s to lower 80s. Lows in the mid 50s to lower 60s. && .AVIATION /19Z FRIDAY THROUGH WEDNESDAY/... As of 230 PM EDT Friday... Low pressure over central Virginia will move east and offshore tonight. This will allow the lower clouds over northern VA and the MD eastern shore to move southward overnight. Will bring all sites to MVFR late this afternoon into this evening as the boundary moves southward. Showers may impact RIC, PHF and ORF late this afternoon into this evening, while thunderstorms are possible at or near ECG after 21z. VFR conditions expected on Saturday. North to northeast winds expected through the period (except initially westerly at ECG late this afternoon). Outlook: Mainly dry/VFR most of Saturday, but another chance for showers Saturday night into Sunday. Dry conditions return Monday. && .AVIATION /00Z SATURDAY THROUGH WEDNESDAY/... As of 755 PM EDT Friday... Low pressure off the NC coast will move out to sea overnight while an upper level trough moves pivots through the area. As a result, scattered showers (and isolated storms in S portions of NE NC) will continue to be possible for the next few hours before gradually tapering off from W to E. Some hi-res CAMs show the potential for some light showers lingering near ORF/ECG late tonight into Sat morning, but confidence is too low to reflect in the tafs. BKN/OVC conditions this evening (MVFR CIGs inland and MVFR/IFR CIGs along the coast) gradually become SCT/BKN late tonight before improving Sat afternoon. ORF/PHF/ECG/SBY may bounce around between IFR/MVFR CIGs (800-1000 ft) over the next few hours before they improve to MVFR. CIGs improve to VFR by Sat afternoon. Winds remain generally N/NNE 5-10 kt tonight (10-15 kt with gusts to 20 kt over the next few hours), becoming variable ~5-7 kt Sat. Another cold front brings the chance for scattered showers (and perhaps an isolated storm) late Sat afternoon into early Sat night. Outlook: Isolated to scattered showers and storms are possible Sun across NE portions of the FA (including SBY). Dry conditions return Monday. Unsettled weather returns Tue-Wed as another low pressure system approaches the FA. && .MARINE... As of 320 PM EDT Friday... Key Messages: -Small Craft Advisories are in effect for all of Bay and lower James River and Atlantic Ocean through Saturday morning- afternoon. -Prevailing sub-advisory conditions return by Saturday afternoon/evening, and are expected to persist through at least Monday. The front has pushed south into NC and behind it, winds have turned to the NE and are generally 15-20 kt with some gusts to 25 kt across all water northern waters. WInds have been preforming well and in line with the ARW and HRRR with decent CAA and water temps in the 60s to near 70F in many areas mixing the wind. Expect N-NNE winds to remain around 20kt (with frequent 25kt gusts) through much of the night. A few 30kt gusts are possible. The SCAs run through Sat AM- Sat aftn (ending across the nrn waters earliest/srn waters latest). Seas build to ~6ft across all ocean zones tonight, with 3-4ft waves on the bay. Winds quickly diminish to ~10kt by early Sat aftn as the pressure gradient relaxes as the low moves well offshore. Seas should quickly fall below 5ft by mid to late aftn. A secondary front tracks across the coast later Saturday aftn/evening. The wind becomes SE 10-15kt ahead of the front and then shifts to NW late Saturday night/early Sunday. The current forecast is sub-SCA, although some guidance suggests low-end SCA conditions are possible over the Ches Bay. High pressure builds over the coast later Sunday into Monday. Another low pressure system and weak cold front impact the Mid-Atlantic coast in the Tuesday- Wednesday timeframe. && .TIDES/COASTAL FLOODING... As of 320 PM EDT Friday... -Key Messages: -A Coastal Flood Statement has been added for the bay side of the MD Eastern Shore for the high tide late tonight/early tomorrow morning. -Coastal Flood Advisories have been issued for almost all of the area bordering the Chesapeake Bay, Atlantic Ocean, and tidal rivers for tonight`s high tide. -Minor tidal flooding (inundation of ~1 foot above ground level in vulnerable areas) is expected during high tide tonight into early Saturday. An increasing NE then N wind tonight into early Saturday along with elevated astronomical tides will bring a round of widespread minor tidal flooding across the area. Water levels are expected to crest a few tenths of a foot above minor flood thresholds in areas adjacent to the Ches Bay, Atlantic Ocean, and tidal rivers during tonight`s high tide cycle. Levels at Oyster may crest right at the moderate flood threshold for that site. Coastal Flood Advisories still in effect for all areas except the bay side of the MD Eastern Shore. A Coastal Flood Statement has been added for the bay side of the MD Eastern Shore for the high tide late tonight due to expected near-minor flooding. && .AKQ WATCHES/WARNINGS/ADVISORIES... MD...Coastal Flood Advisory until 2 AM EDT Saturday for MDZ024-025. NC...Coastal Flood Advisory until 1 AM EDT Saturday for NCZ102. VA...Coastal Flood Advisory until 2 AM EDT Saturday for VAZ099-100. Coastal Flood Advisory from 1 AM to 7 AM EDT Saturday for VAZ075-077. Coastal Flood Advisory from 11 PM this evening to 6 AM EDT Saturday for VAZ076-078-085-521-522. Coastal Flood Advisory until 3 AM EDT Saturday for VAZ084-086- 095-097-098-523. Coastal Flood Advisory until 5 AM EDT Saturday for VAZ089-090- 093-096-524-525. MARINE...Small Craft Advisory until 7 AM EDT Saturday for ANZ630-631- 638. Small Craft Advisory until 10 AM EDT Saturday for ANZ632-634- 650-652-654. Small Craft Advisory until 10 AM EDT Saturday for ANZ633. Small Craft Advisory until 4 PM EDT Saturday for ANZ656-658. && $$ SYNOPSIS...RHR/MRD NEAR TERM...RMM/MRD SHORT TERM...MRD LONG TERM...MRD AVIATION...RMM MARINE...AM/JAO TIDES/COASTAL FLOODING...
Area Forecast Discussion
National Weather Service Corpus Christi TX
1104 PM CDT Fri May 10 2024 ...New AVIATION... .UPDATE... Issued at 918 PM CDT Fri May 10 2024 Several coastal sites and buoy 42019 suggest a predominate Small Craft Exercise caution condition, which is consistent with the NAM and RAP deterministic runs. The RAP/NAM winds over the waters are predicted to decrease somewhat by 09z Saturday. Nevertheless, decided to increase wind over the waters to the Small Craft Exercise Caution threshold of 15-20kt for tonight. && .SHORT TERM... (Tonight through Saturday night) Issued at 244 PM CDT Fri May 10 2024 Key Messages: - Low chance (15-30%) showers and thunderstorms tonight through Saturday night. A diffuse cold front that has either moved through or is just moving through the region will continue over the region. The wind direction and trough is south of BRO, while the thermal and moisture gradient is just starting to move into the northern Brush Country and the Victoria Crossroads. If you use the 850 temperatures as a proxy, the GFS has the front part way through the Brush Country and the Rio Grande Plains by 12z/Sat, while the ECMWF holds the front back to the northwest. In either case, the front will slowly move through or fizzle over the next 36 hours. This leads to the chance of showers and thunderstorms, especially with PWAT values of 1.5-1.8" over the region. Saturday night, the a 500 mb shortwave trough begins to move east into west Texas, but at this point it looks like the precipitation will stay out until later on Sunday. && .LONG TERM... (Sunday through next Thursday) Issued at 244 PM CDT Fri May 10 2024 Key Messages: - Low to moderate chance for showers and storms through Monday An unsettled pattern will be in place through Sunday and Monday as a mid-level low pressure center moves out of the Rockies and into the Central US. Shortwaves rotating through the flow associated with this low will help to give us some rain chances, though the best rain chances will continue to be over northern parts of our forecast area (mainly the northern Coastal Bend and Victoria Crossroads. Moisture will be streaming northward with continued low level southeasterly flow. PWAT values approach 2" for eastern portions of our area, but a CAP in place will limit thunderstorm activity. Higher resolution guidance that goes out through Sunday shows little activity over our area. Another low end (20-30%) rain chance returns Thursday as the ridge breaks down and we may actually get another front approaching the area Friday. Mid-level ridging builds for the middle part of the week with warming temperatures and continued high dewpoints leading to uncomfortable humidity. Heat index values around or slightly above 100 will be expected Monday through Thursday while high temperatures will be in the 90s for much of the area, with mid and upper 80s northeast. Monday looks like the hottest day west with temps at or slightly above 100 in the Rio Grande Plains. && .AVIATION... (06Z TAFS) Issued at 1101 PM CDT Fri May 10 2024 Expect predominate MVFR ceilings tonight through early Saturday afternoon, followed by a mixture of MVFR/VFR for the afternoon, followed by a transition to predominate MVFR again toward the end of the TAF period. Isolated showers are expected tonight through Saturday morning, followed by isolated showers and thunderstorms, especially over the southern terminals (LRD, ALI, CRP), Saturday afternoon. Generally weak to moderate northeast/east flow overnight/early Saturday, followed by east/southeast flow for the remainder of the TAF period. && .MARINE... Issued at 244 PM CDT Fri May 10 2024 Weak to moderate northeasterly flow is expected to persist through Saturday before veering more easterly. Patchy fog and haze will continue to impact the waters ahead of the boundary. There is a 15-25% chance for showers and thunderstorms Saturday and Saturday night. Weak to moderate southeasterly flow will continue Sunday through late in the week. There is a 20-50% chance of showers and thunderstorms both Sunday and Monday. Drier conditions are in store by Tuesday. Low end rain chances return by late week. && .PRELIMINARY POINT TEMPS/POPS... Corpus Christi 77 85 76 90 / 30 10 20 30 Victoria 72 86 73 87 / 10 10 20 60 Laredo 75 90 75 97 / 20 20 30 10 Alice 74 87 75 92 / 30 20 20 30 Rockport 76 85 76 87 / 10 10 10 40 Cotulla 75 88 75 95 / 20 20 30 20 Kingsville 76 85 75 90 / 30 20 20 30 Navy Corpus 78 85 78 87 / 30 20 20 30 && .CRP WATCHES/WARNINGS/ADVISORIES... TX...None. GM...None. && $$ SHORT TERM...JSL LONG TERM....PH AVIATION...WC/87
Area Forecast Discussion
National Weather Service Austin/San Antonio TX
626 PM CDT Fri May 10 2024 ...New AVIATION... .SHORT TERM... (Tonight through Saturday night) Issued at 148 PM CDT Fri May 10 2024 Morning mid-level clouds were indicative of some unplanned shower and storm activity in our eastern and southern counties and that has come to fruition with some scattered activity continuing in the east. Northeast winds prevail at the surface with speeds around 10 to 20 mph with some slightly higher gusts. Southwest flow aloft continues across the region and with some upslope flow on the higher terrain west of the Rio Grande could induce some scattered showers and storms in Mexico late this afternoon. Some of this activity could push east into our Rio Grande counties. The HRRR has backed off this scenario and lowered PoPs slightly as a result. SPC has also removed the western counties from the marginal risk as well. Skies will range from partly to mostly cloudy tonight with lows in the middle 60s to lower 70s. For tomorrow, southerly flow returns with weak ascent which may lead to isolated showers and perhaps a thunderstorm for the western two- thirds of the area. Highs will be cooler in the 80s for most locations. Rain chances will increase into Saturday night and early Sunday morning as the main support from the approaching shortwave arrives to the area. Rain chances will be in the 20-50 percent range. Some elevated rain amounts may be possible with amounts generally less than 3/4 of an inch. Instability amounts will remain low and not expecting widespread strong storms outside of a small chance for Val Verde County where instability is slightly higher. Lows tomorrow night will be back in the in the middle 60s to lower 70s. && .LONG TERM... (Sunday through Friday) Issued at 148 PM CDT Fri May 10 2024 An active spring pattern continues with a series of upper level systems pivoting from the Desert Southwest through the Central Plains in the coming week. Additionally, rising humidity and returning above average warmth will be expected with prevailing south to southeasterly winds becoming more common within the forecast. The first period for good rain and storm chances over South-Central Texas is expected Sunday into Sunday night with forcing from the first upper level low to the north. Additional shower and storm activity is then possible Monday afternoon as a front slides across the region. Tuesday should be a reprieve in between systems with what looks like a rain free forecast and slightly lower humidity levels. Moisture levels return and the increase in forcing ahead of the next upper level system should bring increasing rain and storm chances from Wednesday through Thursday. A cold front then looks to clear out the rain/storm chances into Friday. With pooling instability and supportive wind shear profiles over South-Central Texas through much of the period, the times when convection does develop, it could become organized. Any storm activity could also produce locally heavy rainfall. Pending on precedent conditions and locality, some instances of flooding is possible. Details, such as placement and timing of convection, become more clear into and through the short term period with assessment of the capping inversion, and mesoscale features or boundaries. Overall, the probability for more than 1 inch of rainfall through the long term are currently more than 50 to 60 percent across the northern and eastern half of the CWA. && .AVIATION... (00Z TAFS) Issued at 626 PM CDT Fri May 10 2024 TSRA/SHRA moving northeast over Central Texas this evening will have no impacts on the TAF sites. VFR flying conditions will prevail with any CIGs above FL050 tonight. CIGs will lower to MVFR out west, including at KDRT on Saturday, then farther east, including the I-35 sites Saturday evening. Northeasterly winds decreasing to near 7 KTs this evening will turn easterly at 7 to 14 KTs out west overnight and elsewhere on Saturday. && .PRELIMINARY POINT TEMPS/POPS... Austin Camp Mabry 67 85 68 81 / 0 10 40 70 Austin Bergstrom Intl Airport 64 83 67 81 / 0 10 40 70 New Braunfels Muni Airport 67 85 68 85 / 0 10 40 60 Burnet Muni Airport 64 81 66 78 / 20 20 40 70 Del Rio Intl Airport 73 88 73 92 / 10 20 40 20 Georgetown Muni Airport 64 82 66 79 / 20 10 40 80 Hondo Muni Airport 69 84 68 87 / 10 20 40 40 San Marcos Muni Airport 65 84 67 83 / 0 10 40 70 La Grange - Fayette Regional 67 84 70 84 / 0 10 30 80 San Antonio Intl Airport 69 84 69 86 / 0 10 40 50 Stinson Muni Airport 70 84 70 86 / 0 10 40 50 && .EWX WATCHES/WARNINGS/ADVISORIES... None. && $$ Short-Term...29 Long-Term...Brady Aviation...04
Area Forecast Discussion
National Weather Service Grand Rapids MI
1037 PM EDT Fri May 10 2024 .KEY MESSAGES... - Cloud forecast for aurora tonight - Showers moving through tonight into Saturday - Back to warm springlike pattern starting Sunday - Rain chances on Monday and Friday && .UPDATE... Issued at 1037 PM EDT Fri May 10 2024 Band/line of gusty showers with embedded tstms continues to advance east from WI and there was recently a gust to 37 kts at Fond Du Lac. This band extrapolates into Ludington shortly before Midnight, continuing south and east from there overnight. Waning instability should bring a decrease in the thunder, but a period of gusty winds will probably still impact the lakeshore and perhaps one more row of counties inland per the HRRR. The band of rain is fairly narrow and while high pops are warranted overnight only 3 hours of so of rain is expected. Given the gusty winds still happening with the showers and well as the period of 15-25kt northwest winds which occurs in the wake of them late tonight through mid afternoon Sat, have issued a Small Craft Advisory for the area south of Whitehall. Latest HRRR updates have become a bit more aggressive with the winds and there is period of solid sustained winds 20-22 kts Saturday morning between Muskegon and Saugatuck. Preceding the incoming showers, there are numerous breaks in the clouds currently, allowing sufficient aurora viewing for most areas. && .DISCUSSION... Issued at 457 PM EDT Fri May 10 2024 - Cloud forecast for aurora tonight Chances of an aurora are high tonight given the levels of various indices that are monitored like the planetary kP index. Values have reached 8 this afternoon which is a high confidence event over Lower Michigan. The issue for folks in Southwest Lower Michigan is the amount of clear skies we will have between reaching darkness and before clouds advance into the area. For instance, sunset in Grand Rapids is 853 pm this evening, but we do not get to complete darkness until around 1005 pm. Clouds per the HREF are advancing into Kent County going on midnight. So, the opportunity in the metro area may be a couple of hours. To the northwest towards Ludington, clouds come in even earlier which may spoil the potential show. Best chances may be for an hour or two from near Grand Rapids off to the south and east. Bottom line, once it gets dark its worth a look to see if skies are clear. Given the magnitude of this event, auroras are likely through the weekend. Saturday night will be a better chance at mainly clear skies. We will have to see whether the aurora chances continue into Saturday night. Monitoring the kP index online may be the best way to see if conditions remain favorable. Anything over a 6 is good for Lower Michigan. 7 to 8 values are much better. The auroral oval forecast is another way to monitor trends online. Final point...the band of clouds in Wisconsin advancing our direction for tonight is fairly narrow, so it may be worth trying to be opportunistic overnight to look for breaks in the cloud cover. - Showers moving through tonight into Saturday A compact system will sweep through Southwest Lower Michigan tonight and into Saturday morning. It looks to have increased in speed and we will likely dry out quicker for Saturday afternoon and evening than was expected yesterday. We have high pops overnight when the main band of rain showers moves through. Precipitation amounts look to be on the order of a tenth or two, so fairly light. Any threat for thunder looks to be fairly small given the time the precipitation is moving through away from the diurnal max. An isolated thunderstorm cannot be ruled out tonight however. Saturday night looks to be mainly clear and cool. Patchy frost is possible across Central Lower Michigan into Sunday morning, but at this point holding off on any headline as our current lows are mainly upper 30s. - Back to warm springlike pattern starting Sunday Deep upper troughing over the eastern CONUS will steadily deamplify starting late this weekend and generally continue through next week. This will gradually shift our mean flow away from the chilly northwesterlies we`re in this weekend, and move in favor of a more typical springlike southwesterly flow pattern. This will allow the return of warmer 850 temperatures into Lower Michigan. Normal high temperatures this time of year are in the upper 60s in Grand Rapids, but we`ll spend much of the upcoming week in the lower to mid 70s. - Rain chances on Monday and Friday There are two main chances for rain for next week. Late Sunday night and during the day Monday Lower Michigan will get pinched between a shortwave passing to our north and a stronger 500 mb wave sliding eastward out of Missouri. While we could see a few showers from the northern wave Sunday night and Monday morning, we`re more likely to see areas of rain form as the southern wave moves through later during the day on Monday. This is not looking like a heavy rainmaker at all, it`ll probably be enough to make for a gloomy wet day for many folks on Monday. Much of the middle part of the week will be very pleasant as we come under the influence of some upper ridging moving into our area from the west. For late in the week, we start to bring a more robust upper trough through the Great Lakes. As it encounters the warm and somewhat humid air that will have worked in here during the midweek period, we`ll need to be alert for thunderstorm potential late next week as better dynamics work their way into the area. Overall, this is a typical springlike pattern and it looks like the classic battle between cool and warm air will continue in our area over the next 10 days. && .AVIATION /00Z TAFS THROUGH 00Z SUNDAY/... Issued at 721 PM EDT Fri May 10 2024 VFR conditions will continue through mid to late evening. A line of showers will move through overnight and some lower MVFR ceilings are expected after midnight especially at the northern terminals. Potential for isolated storms is too low to warrant inclusion in any of the terminal forecasts. Northwest winds will increase and gust to around 20-25 kts Saturday. && .MARINE... Issued at 346 PM EDT Fri May 10 2024 Have opted to not issue a Small Craft Advisory tonight into Saturday, but it will be close. A increase in southwest winds will occur for a couple hours this evening, followed by a cold front sweeping through overnight. Winds may remain elevated on Saturday for a time as well. The issue with this potential event is that winds do not stay up over a longer duration to produce a substantial wave field. The best opportunity may be Saturday morning behind the cold front. The WaveWatch3 produces a couple hours of waves around 4 feet midday on Saturday before they subside once again. Given the borderline wave heights and short duration have held off on the Small Craft Advisory for now. If these levels are maintained we may need to issue a SCA for a time on Saturday. Sunday looks like a better chance at needing a Small Craft Advisory headline as winds ramp up out of the south. The mid lake BUFKIT point even shows a brief period of gales being possible. Given this is a warm air advection event have low confidence in gales. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...None. MARINE...Small Craft Advisory until 5 PM EDT Saturday for LMZ844>847. && $$ UPDATE...Meade DISCUSSION...Duke/AMD AVIATION...Laurens MARINE...Duke
Area Forecast Discussion
National Weather Service Melbourne FL
957 PM EDT Fri May 10 2024 ...New UPDATE, AVIATION, MARINE... .UPDATE... Issued at 955 PM EDT Fri May 10 2024 Conditions are relatively calm but also muggy out there with temperatures in the 80s and dew points in the 60s and low 70s. Mid level drying is evident from this evening`s 23z XMR sounding but this dry layer could be eroded some over the next several hours. An approaching cold front, stretched across the Florida Panhandle, is working its way south. In advance of the front, PW values around 1.6-1.7" are present. RAP analysis indicates some deeper moisture convergence over the FL Big Bend/Nature Coast region, just ahead of an ongoing area of storms west of Steinhatchee. Hi- res guidance, like recent runs of the HRRR/RAP/NAM3km have indicated some level of persistence to this convection as it pushes toward central Florida later tonight. The threat of isolated showers and storms remains highly conditional and not everyone is guaranteed to see rain. However, there appears to be enough model support for at least 20-30 PoP from the Orlando metro area northward. If storms are maintained or further materialize, the parameter space over north-central Florida appears marginally supportive of strong to locally damaging wind gusts, small hail, and even a tornado or waterspout that cannot be completely ruled out. The Storm Prediction Center maintains a Marginal Risk for severe storms from the Melbourne to Kissimmee areas northward overnight. Showers and a few rumbles of thunder may persist as the front marches south through mid morning on Saturday, though an overall gradual dissipation of convection is expected. Temperatures by morning look to start out in the low to mid 70s. && .AVIATION... (00Z TAFs) Issued at 955 PM EDT Fri May 10 2024 VFR continue with a conditional threat of isolated SHRA/TSRA after 04z-05z from LEE to MCO to TIX/MLB. For now, VCSH is handling this potential but AMDs or even TEMPOs may be needed for VCTS/TSRA across northern terminals thru 09z. If this activity materializes, it is expected to weaken on approach to Treasure Coast sites after 10z. Brief CIG/VIS reductions to IFR are possible INVOF TSRA. Otherwise, a FROPA is expected thru 12z, perhaps with the front stalling near SUA thru early afternoon Sat. Behind the front, winds will gradually veer WNW, increasing to 10-15 kt by the afternoon. Winds along the coast become ENE as the east coast sea breeze develops and meanders west after 18-21z. && .MARINE... Issued at 955 PM EDT Fri May 10 2024 SW winds become westerly overnight as a cold front approaches and crosses the local waters through daybreak Saturday. An isolated shower or lightning storm may occur over inland waterways and perhaps over the nearshore waters late tonight. Gusty winds and a waterspout cannot be entirely ruled out. As any showers/storms dissipate toward daybreak, winds veer WNW Saturday morning and locally increase nearshore as the sea breeze develops in the afternoon. An isolated shower or storm is possible along the Treasure Coast Saturday. Otherwise, seas 2-3 ft nearshore and up to 4 ft offshore, except where locally higher in and around lightning storms. && .FIRE WEATHER... Issued at 425 AM EDT Fri May 10 2024 Saturday-Monday (modified morning discussion)...Fire-sensitive to near- critical conditions at times this weekend away from the coastal corridor. WNW winds of 10-15 mph will deliver a punch of drier air down the peninsula Saturday, with only a 20-30% storm chance lingering for the Treasure Coast and Lake O region. Across the interior, RH minima will fall to around 30-40% on both Saturday and Sunday afternoons. By Sunday, winds turn to the NE 5-15 mph, strongest along the coast where a sea breeze is forecast. Localized critical conditions are possible on Saturday afternoon, especially from Clermont to Okeechobee (the Kissimmee basin). Winds turn toward the southeast from 10-15 mph on Monday, locally gusting to 20 mph along the coast. This will carry an increase in moisture and a chance for afternoon showers and storms. Wetting rain chances increase, especially across the northern half of Central Florida, from late Monday through mid- week. && .PRELIMINARY POINT TEMPS/POPS... DAB 71 85 67 84 / 30 0 0 0 MCO 74 93 67 91 / 30 10 0 0 MLB 74 87 70 85 / 20 10 0 0 VRB 73 89 69 87 / 20 20 0 10 LEE 73 90 67 90 / 30 0 0 0 SFB 73 92 67 90 / 30 0 0 0 ORL 74 93 69 90 / 30 10 0 0 FPR 72 90 68 87 / 20 20 0 10 && .MLB WATCHES/WARNINGS/ADVISORIES... FL...None. AM...None. && $$ UPDATE...Schaper LONG TERM...Schaper AVIATION...Schaper
Area Forecast Discussion
National Weather Service San Francisco CA
833 PM PDT Fri May 10 2024 ...New UPDATE... .SYNOPSIS... Issued at 125 PM PDT Fri May 10 2024 Warm temperatures continue inland through Saturday with highs from the upper 80s to lower 90s. Cooling has begun at the coast and spreads inland over the weekend into Monday with seasonal to warm temperatures through the next week. && .UPDATE... Issued at 832 PM PDT Fri May 10 2024 Low clouds can be seen on satellite imagery over the Monterey Bay region and are expanding inland at this hour. Also, they are working there way up the San Franciso Peninsula and spreading inland around Santa Cruz. The latest HRRR has them spreading inland overnight up and down our entire coastline, through the Golden Gate and locally into the Salinas Valley. This may be a bit overdone, but the general trend is for them to expand in coverage first over the ocean and then inland. Overall, the forecast remains on track with no updates anticipated at this time. && .SHORT TERM... (This evening through Saturday) Issued at 125 PM PDT Fri May 10 2024 A larger scale ridge is starting to weaken as it comes into the Pacific Northwest, diminishing the offshore flow that contributed to the warm coastal temperatures the last two days. Satellite imagery shows stratus decks along the Big Sur coast, flowing into Monterey Bay and the coast of the San Mateo Peninsula. While this definitely looks like a southerly surge, observed coastal winds are more westerly than southerly, helping to cool off the coastal regions as the breezes develop through the day. Downtown San Francisco, which hit a high of 81 yesterday, is forecast to top out at 76 today. Elsewhere, the Pacific coast should expect highs around the low to mid 60s while the Bayshore could see highs reach the low 80s today. Further cooling is expected on Saturday with the coast seeing highs around 60 and the Bayshore seeing highs in the mid to upper 70s. Without the moderating impact of the onshore sea breeze, and with the ridge axis moving into the state, interior regions remain warm. The highs today will range from the upper 80s to lower 90s across the interior valleys with similar highs expected to continue into tomorrow. A Minor HeatRisk throughout the inland area, and a Moderate HeatRisk for the interior North Bay, East Bay, and South Bay will continue into Saturday; this means that a low to moderate risk of heat-related illnesses continues for vulnerable populations. The higher elevations should see highs in the 70s with a few degrees of cooling on Saturday. Low temperatures throughout the region on Saturday morning will hover in the low to mid 50s in the lower elevations, and the upper 50s to low 60s in the mountains. Given the continuing warm temperatures inland, here`s a reminder of some heat safety tips: * Stay hydrated and drink plenty of fluids. * Wear lightweight, light-colored clothing. * Reduce time spent outdoors or stay in the shade. * Never leave people or pets unattended in vehicles. * Use sunscreen if going to the coast or the pool. Satellite imagery is also showing some pop-up clouds over the area near San Bruno Mountain. The HREF and NAM are suggesting some chance of showers over the extreme south of San Bruno County and southeast of Monterey County through the afternoon. The HRRR isn`t showing any rainfall developing in the area. The forecast shows a slight chance of showers in the area, which was carried forward from overnight. If showers do develop, any rainfall totals will be very light with around a few hundredths of an inch at most. && .LONG TERM... (Saturday night through next Thursday) Issued at 125 PM PDT Fri May 10 2024 The weakening ridge will allow for a cooling and moistening trend to start for the interior regions and continue in the coastal regions on Sunday into Monday, with slight fluctuations in the temperature expected through the upcoming work week. Coastal locations will rise to the low to mid 60s through the end of the next week, with the inland valleys hovering around the low to mid 80s for the most part, perhaps up to the upper 80s in the warmest spots. Tuesday, in particular, should see an uptick in the temperatures as a second ridge comes into the Pacific Northwest, combining with a weak upper level low tracking into southern California to bring some northeasterly flow to the region. Atmospheric moisture does begin to develop through the region towards the middle and end of next week, although the highest chances for precipitation appear to lie near the Sierras. Ensemble clusters are hinting at a possible trough coming through the western United States around the end of next week or the upcoming weekend. The CPC`s 8-14 day outlook suggests that temperature and precipitation for the period between the 18th and the 24th will be around the seasonal averages. && .AVIATION... (00Z TAFS) Issued at 459 PM PDT Fri May 10 2024 VFR at most terminals through the period with stratus expected to impact MRY and SNS. Light to moderate W to NW winds continue into the evening before winds become light at all stations. HREF guidance shows stratus extending inland into the Monterey Peninsula and northward along the SF Peninsula. Some stratus concerns for SFO depending on how far inland stratus moves along the SF peninsula but for now stratus looks to stay west of SFO. Low confidence that stratus will reach OAK with HREF keeping stratus primarily along the coast but indicating some may creep into the SF Bay. Vicinity of SFO...Currently VFR through the TAF period. Trends continue to keep stratus mostly confined along the coast and portions of the SF Bay. General timing for few to scattered clouds over SFO remains with the same with low confidence that a ceiling will develop. HREF does show stratus extending inland over SFO so will continue to keep watch on stratus development. SFO Bridge Approach...Similar to SFO. Monterey Bay Terminals...VFR through the evening. Visible satellite shows stratus lingering over the Monterey Bay and portions of the Watsonville/Santa Cruz coastline. Current observations show primarily SW winds which should help keep stratus away from MRY and SNS through the evening. Winds are expected to shift more W/NW by the late evening which will allow for some few to scattered clouds to filter in between 03-06Z. Stratus will fill in at both stations between 10-11Z. Low confidence but a few models indicated stratus may filter into the Salinas Valley earlier between 07-8Z. && .MARINE... (Tonight through next Wednesday) Issued at 459 PM PDT Fri May 10 2024 Light to moderate winds over the coastal waters will continue through Saturday as a weak surface trough lingers over the coast. By the beginning of the work week, high pressure will build, move east, and bring building significant wave heights, continued dry weather, and strengthening northwesterly winds from light to moderate winds to a fresh breeze. && .BEACHES... Issued at 719 PM PDT Fri May 10 2024 Long period southwest swell will lead to slightly elevated chances for sneaker wave and rip current development this weekend. Conditions are expected to stay below Beach Hazards Statement criteria as swell height will only be between 1-2 feet. However, in light of anomalously warm temperatures and increased likelihood of people traveling to the coast, visitors to the beach should remember to take safety precautions to prevent being caught by an unexpected large wave and to never turn your back on the ocean. && .MTR WATCHES/WARNINGS/ADVISORIES... CA...None. PZ...None. && $$ UPDATE...RGass SHORT TERM...DialH LONG TERM....DialH AVIATION...Kennedy MARINE...Kennedy BEACHES...Kennedy Visit us at www.weather.gov/sanfrancisco Follow us on Facebook, Twitter, and YouTube at: www.facebook.com/nwsbayarea www.twitter.com/nwsbayarea www.youtube.com/nwsbayarea