{"id":1034,"date":"2025-07-19T17:25:44","date_gmt":"2025-07-19T17:25:44","guid":{"rendered":"https:\/\/discussions.weather.arizona.edu\/?p=1034"},"modified":"2025-07-19T17:30:20","modified_gmt":"2025-07-19T17:30:20","slug":"some-rain-here-and-there-mostly-there-just-some-cirrus-near-us-july-19th-2025","status":"publish","type":"post","link":"https:\/\/discussions.weather.arizona.edu\/?p=1034","title":{"rendered":"Some rain here and there, mostly there&#8230;just some cirrus near-us: July 19th, 2025"},"content":{"rendered":"\n<h2 class=\"wp-block-heading\">Yesterday&#8217;s Weather<\/h2>\n\n\n\n<p>Model forecasts did a good job with the convection in southeast Arizona and New Mexico as shown in the radar images below. The area of storms continued to move west to the Pima County line, with a few developing along outflows in the Green Valley area, Outflows from these storms pushed as far west and north as Casa Grande and Phoenix after midnight.&nbsp;<\/p>\n\n\n\n<figure class=\"wp-block-video\"><video height=\"572\" style=\"aspect-ratio: 1732 \/ 572;\" width=\"1732\" autoplay controls loop muted src=\"https:\/\/discussions.weather.arizona.edu\/wp-content\/uploads\/2025\/07\/Recording-2025-07-19-080757.mp4\"><\/video><figcaption class=\"wp-element-caption\">HRRR-UA WRF 12Z simulated radar reflectivity forecast from yesterday (left) versus observed composite radar reflectivity from MRMS (right)<\/figcaption><\/figure>\n\n\n\n<h2 class=\"wp-block-heading\">Analysis<\/h2>\n\n\n\n<p>The tropical upper tropospheric trough (TUTT) in Mexico is weakening along the west side of the Sierra Madre&#8217;s and becoming a shear line with strong southerly winds to the east of the shear axis. The strongest winds can be inferred from the water vapor imagery below, where the divide between moist and dry air is in western Arizona. The other TUTT, now in the southern Gulf of California, is accompanied by a large are of convection.<\/p>\n\n\n\n<figure class=\"wp-block-video\"><video height=\"820\" style=\"aspect-ratio: 1268 \/ 820;\" width=\"1268\" autoplay controls loop muted src=\"https:\/\/discussions.weather.arizona.edu\/wp-content\/uploads\/2025\/07\/Recording-2025-07-19-082914.mp4\"><\/video><figcaption class=\"wp-element-caption\">GOES19 upper level water vapor images for July 19th from midnight to 8am, College of DuPage<\/figcaption><\/figure>\n\n\n\n<p>At 250mb, a ridge is over southern Oklahoma with ridge axis extending west to central Arizona. The TUTT off the spur of Baja has become an open&nbsp;wave connecting with the trough further north. &nbsp;<\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-full is-resized\"><img loading=\"lazy\" decoding=\"async\" width=\"730\" height=\"752\" src=\"https:\/\/discussions.weather.arizona.edu\/wp-content\/uploads\/2025\/07\/Screenshot-2025-07-19-090140.png\" alt=\"\" class=\"wp-image-1040\" style=\"width:680px;height:auto\" srcset=\"https:\/\/discussions.weather.arizona.edu\/wp-content\/uploads\/2025\/07\/Screenshot-2025-07-19-090140.png 730w, https:\/\/discussions.weather.arizona.edu\/wp-content\/uploads\/2025\/07\/Screenshot-2025-07-19-090140-291x300.png 291w\" sizes=\"auto, (max-width: 730px) 100vw, 730px\" \/><\/figure>\n<\/div>\n\n\n<p>The high pressure ridge and ridge axis at 500mb are in about the same position as the 200mb ridge\/axis. Temperatures are colder in western Arizona than eastern Arizona and New Mexico. No soundings were available from KABQ, KPSR, KTUS, or MMGM this morning, so understanding today&#8217;s flow pattern is more a lot more uncertain. Flow is light from the east over most of the region and southerly at 20 knots over western Arizona. What remains of the TUTT that was over northern Baja California yesterday is now over San Diego.&nbsp;<\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-full is-resized\"><img loading=\"lazy\" decoding=\"async\" width=\"733\" height=\"752\" src=\"https:\/\/discussions.weather.arizona.edu\/wp-content\/uploads\/2025\/07\/Screenshot-2025-07-19-090256.png\" alt=\"\" class=\"wp-image-1041\" style=\"width:661px;height:auto\" srcset=\"https:\/\/discussions.weather.arizona.edu\/wp-content\/uploads\/2025\/07\/Screenshot-2025-07-19-090256.png 733w, https:\/\/discussions.weather.arizona.edu\/wp-content\/uploads\/2025\/07\/Screenshot-2025-07-19-090256-292x300.png 292w\" sizes=\"auto, (max-width: 733px) 100vw, 733px\" \/><\/figure>\n<\/div>\n\n\n<p>The monsoon circulation at 700mb is from the spine of the Sierra Madre\u2019s northward to southern Arizona then northeast into central New Mexico and then to Kansas. Low pressure is near San Diego while a ridge is over Texas with the ridge axis extending west across into northern Arizona.&nbsp;<\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-full is-resized\"><img loading=\"lazy\" decoding=\"async\" width=\"740\" height=\"752\" src=\"https:\/\/discussions.weather.arizona.edu\/wp-content\/uploads\/2025\/07\/Screenshot-2025-07-19-090316.png\" alt=\"\" class=\"wp-image-1043\" style=\"width:676px;height:auto\" srcset=\"https:\/\/discussions.weather.arizona.edu\/wp-content\/uploads\/2025\/07\/Screenshot-2025-07-19-090316.png 740w, https:\/\/discussions.weather.arizona.edu\/wp-content\/uploads\/2025\/07\/Screenshot-2025-07-19-090316-295x300.png 295w\" sizes=\"auto, (max-width: 740px) 100vw, 740px\" \/><\/figure>\n<\/div>\n\n\n<p>Yesterday&#8217;s HRRR-UA WRF 12Z model forecast sounding for Tucson is on the left, and this morning&#8217;s HRRR-UA WRF 12Z is on the right. The forecasts agree with only a minor differences in winds in the layer between 700mb and 500mb, and 3mm more of precipitable water. <\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"577\" src=\"https:\/\/discussions.weather.arizona.edu\/wp-content\/uploads\/2025\/07\/Screenshot-2025-07-19-094504-1024x577.png\" alt=\"\" class=\"wp-image-1045\" srcset=\"https:\/\/discussions.weather.arizona.edu\/wp-content\/uploads\/2025\/07\/Screenshot-2025-07-19-094504-1024x577.png 1024w, https:\/\/discussions.weather.arizona.edu\/wp-content\/uploads\/2025\/07\/Screenshot-2025-07-19-094504-300x169.png 300w, https:\/\/discussions.weather.arizona.edu\/wp-content\/uploads\/2025\/07\/Screenshot-2025-07-19-094504-768x433.png 768w, https:\/\/discussions.weather.arizona.edu\/wp-content\/uploads\/2025\/07\/Screenshot-2025-07-19-094504.png 1224w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><figcaption class=\"wp-element-caption\">Yesterday&#8217;s HRRR-UA WRF 12Z forecast sounding at Tucson for 5am this morning (left), and today&#8217;s HRRR-UA WRF 12Z initialization at 5am (right).<\/figcaption><\/figure>\n\n\n\n<h2 class=\"wp-block-heading\">Today<\/h2>\n\n\n\n<p>Today is going to be a repeat of yesterday, except the storms will be further west in Arizona. Storms start earlier near and over the mountains, and a second group of overnight storms will move into southeast Arizona overnight. <\/p>\n\n\n\n<figure class=\"wp-block-video\"><video height=\"740\" style=\"aspect-ratio: 1110 \/ 740;\" width=\"1110\" autoplay controls loop muted src=\"https:\/\/discussions.weather.arizona.edu\/wp-content\/uploads\/2025\/07\/Recording-2025-07-19-095212.mp4\"><\/video><figcaption class=\"wp-element-caption\">HRRR-UA WRF 12Z simulated radar reflectivity forecast from 11am to 5am tomorrow morning.<\/figcaption><\/figure>\n\n\n\n<p>Precipitation in the valleys will be light.<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"680\" src=\"https:\/\/discussions.weather.arizona.edu\/wp-content\/uploads\/2025\/07\/Screenshot-2025-07-19-095455-1024x680.png\" alt=\"\" class=\"wp-image-1051\" srcset=\"https:\/\/discussions.weather.arizona.edu\/wp-content\/uploads\/2025\/07\/Screenshot-2025-07-19-095455-1024x680.png 1024w, https:\/\/discussions.weather.arizona.edu\/wp-content\/uploads\/2025\/07\/Screenshot-2025-07-19-095455-300x199.png 300w, https:\/\/discussions.weather.arizona.edu\/wp-content\/uploads\/2025\/07\/Screenshot-2025-07-19-095455-768x510.png 768w, https:\/\/discussions.weather.arizona.edu\/wp-content\/uploads\/2025\/07\/Screenshot-2025-07-19-095455.png 1110w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><figcaption class=\"wp-element-caption\">HRRR-UA WRF 12Z total accumulated precipitation forecast through to 5am tomorrow morning.<\/figcaption><\/figure>\n\n\n\n<h2 class=\"wp-block-heading\">Tomorrow<\/h2>\n\n\n\n<p>Overnight, storms will move across southeast Arizona and the Phoenix area, then into northern Arizona by late afternoon. This will inhibit convection in the low deserts, including Tucson. Afternoon storms still form in far southeast Arizona and New Mexico.<\/p>\n\n\n\n<figure class=\"wp-block-video\"><video height=\"736\" style=\"aspect-ratio: 1114 \/ 736;\" width=\"1114\" autoplay controls loop muted src=\"https:\/\/discussions.weather.arizona.edu\/wp-content\/uploads\/2025\/07\/Recording-2025-07-19-095808.mp4\"><\/video><figcaption class=\"wp-element-caption\">HRRR-UA WRF 12Z simulated radar reflectivity forecast for tomorrow 12:30pm to 5am Monday morning.<\/figcaption><\/figure>\n\n\n\n<h2 class=\"wp-block-heading\">Outlook<\/h2>\n\n\n\n<p>On Monday, low-level moisture increases. HRRR-UA WRF forecasts precipitable water to increase to 46mm (1.8&#8243;), which is plenty for deep convection. The GFS-UA WRF doesn&#8217;t have as much moisture as the HRRR-UA WRF for eastern Pima, Santa Cruz, or Cochise counties.&nbsp;<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"335\" src=\"https:\/\/discussions.weather.arizona.edu\/wp-content\/uploads\/2025\/07\/Screenshot-2025-07-19-100749-1024x335.png\" alt=\"\" class=\"wp-image-1056\" srcset=\"https:\/\/discussions.weather.arizona.edu\/wp-content\/uploads\/2025\/07\/Screenshot-2025-07-19-100749-1024x335.png 1024w, https:\/\/discussions.weather.arizona.edu\/wp-content\/uploads\/2025\/07\/Screenshot-2025-07-19-100749-300x98.png 300w, https:\/\/discussions.weather.arizona.edu\/wp-content\/uploads\/2025\/07\/Screenshot-2025-07-19-100749-768x251.png 768w, https:\/\/discussions.weather.arizona.edu\/wp-content\/uploads\/2025\/07\/Screenshot-2025-07-19-100749-1536x503.png 1536w, https:\/\/discussions.weather.arizona.edu\/wp-content\/uploads\/2025\/07\/Screenshot-2025-07-19-100749.png 1726w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><figcaption class=\"wp-element-caption\">HRRR-UA WRF 12Z (left), GFS-UA WRF 00Z (right), precipitable water forecast for Monday at 2pm.<\/figcaption><\/figure>\n\n\n\n<p><br>It will be a battle of the models on Monday as the HRRR-UA WRF shows some heavy rain in the valleys (half an inch for Tucson!). Meanwhile, the GFS-UA WRF has much lighter precipitation totals, if there&#8217;s any rain at all. Typically, we favor the HRRR forced UA WRF forecasts because of its data assimilation algorithm that ingests recent radar and satellite observations to kick off the model (initialization) in a way that is as close to the current observed conditions as possible.\u00a0<br><\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"332\" src=\"https:\/\/discussions.weather.arizona.edu\/wp-content\/uploads\/2025\/07\/Screenshot-2025-07-19-100304-1024x332.png\" alt=\"\" class=\"wp-image-1055\" srcset=\"https:\/\/discussions.weather.arizona.edu\/wp-content\/uploads\/2025\/07\/Screenshot-2025-07-19-100304-1024x332.png 1024w, https:\/\/discussions.weather.arizona.edu\/wp-content\/uploads\/2025\/07\/Screenshot-2025-07-19-100304-300x97.png 300w, https:\/\/discussions.weather.arizona.edu\/wp-content\/uploads\/2025\/07\/Screenshot-2025-07-19-100304-768x249.png 768w, https:\/\/discussions.weather.arizona.edu\/wp-content\/uploads\/2025\/07\/Screenshot-2025-07-19-100304-1536x499.png 1536w, https:\/\/discussions.weather.arizona.edu\/wp-content\/uploads\/2025\/07\/Screenshot-2025-07-19-100304.png 1731w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><figcaption class=\"wp-element-caption\">HRRR-UA WRF 12Z (left), GFS-UA WRF 00Z (right), simulated radar reflectivity forecast for Monday at 2pm.<\/figcaption><\/figure>\n\n\n\n<p>However, if we compare these two model runs to the GEFS plume forecasts below, the HRRR-UA WRF would be an outlier. These are 3-day ahead forecasts, so there&#8217;s a fair amount of uncertainty. Tomorrow&#8217;s forecasts should tell us more.&nbsp;<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"973\" height=\"740\" src=\"https:\/\/discussions.weather.arizona.edu\/wp-content\/uploads\/2025\/07\/Screenshot-2025-07-19-101306.png\" alt=\"\" class=\"wp-image-1057\" srcset=\"https:\/\/discussions.weather.arizona.edu\/wp-content\/uploads\/2025\/07\/Screenshot-2025-07-19-101306.png 973w, https:\/\/discussions.weather.arizona.edu\/wp-content\/uploads\/2025\/07\/Screenshot-2025-07-19-101306-300x228.png 300w, https:\/\/discussions.weather.arizona.edu\/wp-content\/uploads\/2025\/07\/Screenshot-2025-07-19-101306-768x584.png 768w\" sizes=\"auto, (max-width: 973px) 100vw, 973px\" \/><figcaption class=\"wp-element-caption\">Global Ensemble Forecast System (GEFS) <a href=\"https:\/\/www.emc.ncep.noaa.gov\/users\/meg\/gefs_plumes\/index.html?stationname=KTUS\">plumes <\/a>for Tucson.<\/figcaption><\/figure>\n\n\n\n<p>Discussion written by Pat Holbrook and Patrick Bunn<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Yesterday&#8217;s Weather Model forecasts did a good job with the convection in southeast Arizona and New Mexico as shown in the radar images below. The area of storms continued to move west to the Pima County line, with a few developing along outflows in the Green Valley area, Outflows from these storms pushed as far &hellip;<\/p>\n","protected":false},"author":3,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-1034","post","type-post","status-publish","format-standard","hentry","category-uncategorized"],"_links":{"self":[{"href":"https:\/\/discussions.weather.arizona.edu\/index.php?rest_route=\/wp\/v2\/posts\/1034","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/discussions.weather.arizona.edu\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/discussions.weather.arizona.edu\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/discussions.weather.arizona.edu\/index.php?rest_route=\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/discussions.weather.arizona.edu\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1034"}],"version-history":[{"count":18,"href":"https:\/\/discussions.weather.arizona.edu\/index.php?rest_route=\/wp\/v2\/posts\/1034\/revisions"}],"predecessor-version":[{"id":1065,"href":"https:\/\/discussions.weather.arizona.edu\/index.php?rest_route=\/wp\/v2\/posts\/1034\/revisions\/1065"}],"wp:attachment":[{"href":"https:\/\/discussions.weather.arizona.edu\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1034"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/discussions.weather.arizona.edu\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1034"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/discussions.weather.arizona.edu\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1034"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}