####018004938#### FXUS64 KMEG 260442 AFDMEG Area Forecast Discussion National Weather Service Memphis TN 1142 PM CDT Thu Apr 25 2024 ...New AVIATION... .UPDATE... Issued at 939 PM CDT Thu Apr 25 2024 A stationary surface front is situated across central MS into southern AR this evening. Meanwhile, an elevated warm front is lifting northeast and a weak mid-level shortwave trough is moving through the upper ridge over the region. These features are combining to generate a band of showers across the northern parts of the Mid-South. Made some adjustments to continue precip chances for a few more hours as latest radar imagery shows light showers as far south as Poinsett County. Precip will gradually taper off after midnight. Saturday looks mainly dry and increasingly warm and more humid as the stationary front lifts north as a warm front during the morning and southerly winds develop. Showers and a few storms will begin to threaten NE AR late in the day. && .SYNOPSIS... Issued at 300 PM CDT Thu Apr 25 2024 Scattered showers and isolated thunderstorms will be possible this evening, mainly to the north of Memphis ahead of a slow moving warm front. After the warm front moves north of the Mid- South, warmer and more humid conditions will spread into the region on Friday and continue through the weekend. Scattered showers and thunderstorms are expected over eastern Arkansas and the Missouri bootheel for Friday and Saturday. Thunderstorms will become more widespread across the entire Midsouth Sunday night through Tuesday, as a Pacific cold front approaches the region. && .DISCUSSION... (This evening through next Wednesday) Issued at 300 PM CDT Thu Apr 25 2024 Skies are cloudy across southern sections of the Mid-South with mostly sunny skies over the remainder of the region. Temperatures this afternoon are in the 60s to around 70 degrees. A large area of showers cover much of east Arkansas, southwest Tennessee and north Mississippi. All of this activity is north of slow moving warm front which extends across extreme southern Arkansas and into central Mississippi. As the warm front lifts north into north Mississippi tonight, the area of showers and isolated thunderstorms will move north into northeast Arkansas and west Tennessee. Temperatures will remain near normal tonight with lows from the mid 50s to lower 60s. On Friday, the warm front continues to move north into the Mid- Mississippi Valley, bringing an end to the threat of rain for areas east of the Mississippi River. Behind the warm front, warmer and more humid air moves into the region. Temperatures will be some 10 to 15 degrees warmer than today with highs in the low to mid 80s. A frontal boundary will stall out across the central and southern Plains by Friday evening. Thunderstorms are expected to form ahead of the front with some the activity reaching areas of the Mid-South west of the Mississippi River for Friday night and Saturday. Most areas should see dry weather for Saturday night through Sunday morning as the thunderstorms that develop over the southern Plains on Saturday are not expected to reach the Mid- South. By Sunday, the cold front will begin to move slowly east reaching western Arkansas by Monday and into the Mid-South on Tuesday. As the front gets closer to the region, showers and thunderstorms will increase in coverage from west to east. Rainfall could become heavy across portions of the Mid-South west of the Mississippi River for Sunday night into Monday. Any threat of severe weather should be confined to areas west of the Mid-South across central and western Arkansas. With extensive cloud cover and rain expected on Monday, temperatures will be cooler. Once the cold front moves through the region, dry weather is expected for Tuesday night. Warmer weather returns to the region for Wednesday with a few thunderstorms possible ahead of an upper level disturbance. && .AVIATION... (06Z TAFS) Issued at 1138 PM CDT Thu Apr 25 2024 SHRAs associated with an elevated warm front and a mid level shortwave will continue to lift northeast. Light east winds will continue overnight shifting to the south early Friday as the surface warm front lifts north. Gusty south winds will prevail for most of Friday along with VFR conds. SHRAs and TSRAs are expected to develop across AR Friday afternoon and push into the Mid-South late in the day into the evening. Mentioned VCTS at JBR and MEM during the evening. Introduced LLWS at JBR, MEM and MKL Friday evening through the overnight as low level jet strengthens across the region. && .MEG WATCHES/WARNINGS/ADVISORIES... AR...None. MO...None. MS...None. TN...None. && $$ PUBLIC FORECAST...SJM AVIATION...SJM ####018006937#### FXUS66 KPQR 260443 AFDPQR Area Forecast Discussion National Weather Service Portland OR 943 PM PDT Thu Apr 25 2024 .SYNOPSIS...Showery and unsettled conditions continue through the weekend into next week as the Pacific Northwest remains under the influence of a rather progressive spring-time weather pattern. Beyond the more persistent chances for rainfall going forward snow levels are expected to drop near pass level(4500ft) tonight into Friday although outside of slushy pavement accumulation most appreciable impacts stay above 5,500ft. The weather trends even a touch cooler early next week. .SHORT TERM...Tonight through Saturday night...This afternoon satellite and radar indicate the bulk of the steadier precipitation has begun to decrease and break to showers as the frontal boundary moves inland ad we quickly transition to post- frontal shower activity. With cooler air now filtering in aloft, snow levels will gradually decrease tonight bottoming out near 4,300-4,500ft come sunrise Friday morning. As a result wet snow likely returns to the higher pass areas like Santiam and Willamette, though that’s not to say snow or a rain/snow mix can’t mix down to the highest reaches of US-26 due to the more convective nature of the precipitation. Still, even at Santiam and Willamette pass the warm antecedent conditions will help to limit pavement accumulation with the bulk of the impacts occurring above 5,300-5,500ft. Due to the late season nature of the snowfall will maintain the current Winter Weather Advisory for the Cascades through Friday evening. It’s worth mentioning as far as general precipitation chances are concerned through Friday, models maintain the most frequent showers over the coast range, Willapa Hills, and Cascades/Cascade foothills although the passage of the broader trough axis through western WA/OR Friday midday and afternoon likely servers to increase shower activity region-wide; even across the Willamette Valley and SW Washington. Late Friday into Saturday the upper-level trough deepens and quickly progress southeastward into the four corners region of the Great Basin. We’ll briefly see upper-level heights rise over the region due to the passage of a weak transient shortwave ridge and both deterministic/ensemble guidance seem confident in a lull or at least noticeable decrease in lingering showers over the lower elevations, especially the central and southern Willamette Valley. However, the arrival of fast moving upper- level shortwave and frontal boundary extending southward off a parent low parked over the gulf of Alaska increases chances for precipitation Saturday afternoon into the evening. At least precipitation amounts don’t look particularly noteworthy due to the quick progression of the aforementioned feature on Saturday with an additional ~0.1” for the inland valleys and 0.3-0.5” for the coast range/Cascades. Once the front passes showers chances generally revert back to the elevated terrain features around western WA/OR the second half of the night. Snow levels Friday night through Saturday night continue to fluctuate between 4500-5500ft. -Schuldt .LONG TERM...Sunday through Wednesday night...For the early to middle portion of next week confidence is high the pattern stays rather progressive, with fronts moving off the northeast Pacific into the Pacific NW. During the late Sunday into Monday time period yet another front will push across the region with post-frontal showers on tap by at least the second half of Monday - model uncertainty is higher regarding the exact timing of this disturbance. Still a bit cooler than that expected for late April, with overall temperatures in the lowlands in the 50s to lower 60s. Snow levels will run 3000 to 4000 ft, which will maintain some snow at times for the higher terrain of the foothills, as well as most of the Cascades. Few showers linger around region on Tuesday, but think most of the day will end up being mostly dry for the inland valleys, as a weak transient ridge glides over the region. But, models show another potent front offshore later Tue night/early Wed, with that front pushing inland late Wed into Wed night. With this, does look to be more rainy that showery by Thursday. After that, models still in quite a bit of flux with low forecast confidence due to large discrepancies in the longwave pattern over the eastern Pacific and CONUS. -Schuldt/Rockey && .AVIATION...Showers continue through Friday as an upper level trough slides west to east across the region. This will result in mountain obscuration, while inland valley locations will see a mix of VFR and MVFR. Some rainshadowing occurring east of the coast range helping to bring areas of VFR in the valley as of 05Z Fri. However, guidance indicating about 50-90 percent chance for cigs 2000-3000 ft through 00Z Sat, and a 30-50 percent chance for cigs 1000-2000 ft 09Z Fri to 21Z Fri. South winds will continue in the 8 to 12 kt range through Fri with gusts 15 to 20 kt returning after 20Z Fri. Notes: The ASOS at KTTD is only available via the dial in option. The AWOS at KMMV is still out of commission. There is no estimated time of repair. PDX AND APPROACHES...A mix of VFR and MVFR with passing showers through the TAF period. If there are any trends to the forecast, HREF guidance indicating maybe more persistent MVFR cigs after 15Z Fri with a 60- 70 percent chance for cigs 2000-3000 ft, then deceasing to 30-50 percent chance after 21Z Fri. /mh && .MARINE...The warm front has passed, though post-frontal conditions allow the Small Craft Advisory to continue, with gusts up to 30 kt possible, decreasing after midnight tonight. Seas are choppy, currently sitting around 7-10 ft at 9 seconds. Winds turn more westerly/northwesterly Thursday night into Friday as the low pressure system pushes inland. Winds begin to ease slightly with gusts to 20-25 kt. However, a westerly swell will enter the waters and build seas to around 9-11 ft. These elevated seas are brief, as the swell height falls Friday night to Saturday. The next frontal system arrives on Saturday, will return gusty southwesterly winds. The latest NBM has decreased confidence in gales, only around 10% on Saturday. -Alviz/JLiu && .PQR WATCHES/WARNINGS/ADVISORIES... OR...Winter Weather Advisory until midnight PDT Friday night for ORZ127-128. WA...None. PZ...Small Craft Advisory until 2 AM PDT Saturday for PZZ210-251>253- 271>273. && $$ www.weather.gov/portland Interact with us via social media: www.facebook.com/NWSPortland www.twitter.com/NWSPortland