Feeds:
Posts
Comments

Archive for the ‘Modeling’ Category

A closed upper low over the Southeastern U.S. combined with a deep tropical moisture connection with Hurricane Joaquin led to historic rainfall and flooding over North and especially South Carolina over the weekend.  A wide swath of central South Carolina from the coast to Columbia received over 20 inches of rainfall in the past week (Fig. 1), much of it in the last 2-3 days.  Figure 2 shows the NASA Integrated Multi-satellitE Retrievals for GPM (IMERG) 24-h rainfall estimates displayed in AWIPS II compared to the official NWS/River Forecast Center rainfall estimate for the period ending 1200 UTC on 4 October.  This is erasing the prevailing drought in the Carolinas, which still had moderate to severe drought in the most recent U.S. Drought Monitor weekly product valid 29 September (Fig. 3).

SPoRT’s real-time configuration of the NASA Land Information System (SPoRT-LIS) runs the Noah land surface model to generate a “best modeled” soil moisture estimate at ~3-km resolution for enhanced situational awareness and input to local/regional numerical weather prediction models.  The SPoRT-LIS was assessed during summer/fall 2014 by the NOAA/NWS weather forecast offices (WFOs) at Houston, TX, Raleigh, NC, and Huntsville, AL. Following an expansion to a full Continental U.S. domain, the SPoRT-LIS was also evaluated more informally by the NWS WFOs at Tucson, AZ and Albuquerque, NM this past summer.  The primary areas of utility has been in drought monitoring and assessing areal and river flooding potential.  However, the Southwestern U.S. offices applied SPoRT-LIS soil moisture fields to enhance situational awareness for wildfire and blowing dust situations as well. Overall, a majority of the users during these assessments expressed substantial utility of the product due to a lack of other real-time high-resolution soil moisture products, and were confident enough to use the product as part of operational, public forecasts.

This extreme rainfall event in the Carolinas was captured nicely by the real-time SPoRT-LIS, which depicted some of the most dramatic changes in total column soil moisture ever documented by SPoRT collaborators.  Figure 4 compares the SPoRT-LIS 0-2 m total column relative soil moisture (RSM) from 28 September (left panel) and 5 October (right panel), with Figure 5 highlighting the 1-week change in 0-2 m RSM as displayed in AWIPS II.  The RSM represents how the volumetric soil moisture scales between wilting (0%) and saturation (100%) for a given soil composition, where the wilting point indicates that vegetation can no longer extract moisture from the soil and saturation indicates no more infiltration is possible (thus all new precipitation goes to runoff). Previous experience by the Huntsville WFO found that total column RSM values of ~60% and above tend to indicate an enhanced threat for areal and river flooding over northern Alabama; however, these thresholds can vary depending on river basin properties and regional soil composition.

Values of total column RSM typically ranged from ~25-35% on 28 September, prior to the significant rain event.  However, by 5 October, total column RSM increased to well above 65% in most areas of central South Carolina, and parts of southern and far western North Carolina.  The maximum weekly change in 0-2 m RSM (Fig. 5) exceeds 58% in central South Carolina — a value never documented in the recent years of real-time SPoRT-LIS output!  Most areas of SPoRT-LIS 0-2 m RSM exceeding ~60% correspond to areas of active minor to major river flooding across parts of southern Virginia and the Carolinas, as depicted in the USGS/NOAA river gauge network this morning (Fig. 6).

Finally, SPoRT is producing an experimental daily, real-time soil moisture percentile product based on a 34-year LIS-Noah county-by-county soil moisture climatology.  The soil moisture percentile map indicates where the current 0-2 m RSM soil moisture values lie in the present day’s historical soil moisture distribution for every county in the Continental U.S. The percentile product valid at 1200 UTC 27 September and 4 October is shown in Figure 7.  Primarily dry soil moisture percentiles are prevalent across the Carolinas on 27 September, corresponding reasonably well to the U.S. Drought Monitor moderate to severe drought areas from Figure 3. However, after the 10-20+ inches of rainfall over the past week, the 4 October soil moisture percentiles completely reversed across the region, with values > 98th percentile occurring in central South Carolina where the most severe flooding is taking place.  SPoRT plans to develop a brief training module on this percentile product prior to dissemination for display in AWIPS II at NWS WFOs, along with the current suite of SPoRT-LIS fields already available in AWIPS II.

Fig. 1. NWS River Forecast Center rainfall analysis for the week ending 1200 UTC 5 October 20125.

Fig. 1. NWS River Forecast Center rainfall analysis for the week ending 1200 UTC 5 October 2015.

Fig. 2. Comparison of NASA Integrated Multi-satellitE Retrievals for GPM (IMERG) rainfall estimate to the NWS/River Forecast Center analysis for the 24-hour period ending 1200 UTC 4 October 2015.

Fig. 2. Comparison of NASA Integrated Multi-satellitE Retrievals for GPM (IMERG) rainfall estimate to the NWS/River Forecast Center analysis for the 24-hour period ending 1200 UTC 4 October 2015.

Fig. 2. U.S. Drought Monitor weekly drought product valid 29 September 2015.

Fig. 3. U.S. Drought Monitor weekly drought product valid 29 September 2015.

Fig. 3. SPoRT-LIS total column (0-2 m) relative soil moisture valid on (left panel) 28 September, and (right panel) 5 October 2015.

Fig. 4. SPoRT-LIS total column (0-2 m) relative soil moisture valid on (left panel) 28 September, and (right panel) 5 October 2015.  Masked white areas represent water or urban pixels.

Fig. 4. One-week change in SPoRT-LIS total column relative soil moisture for the week ending 5 October 2015, as displayed in AWIPS II.

Fig. 5. One-week change in SPoRT-LIS total column relative soil moisture for the week ending 5 October 2015, as displayed in AWIPS II.  Maximum weekly change value > 58% is highlighted by the cursor position.  Masked black areas represent water or urban pixels.

Fig. 6. USGS and NWS River Forecast Center river gauge plot for the morning of 5 October 2015. River gauges experiencing flooding are indicated by the legend in the lower-right.

Fig. 6. USGS / NWS River Forecast Center river gauge plot for the morning of 5 October 2015. River gauges experiencing flooding are indicated by the legend in the lower-right.

Fig. 5. Experimental SPoRT-LIS total column relative soil moisture percentile product, valid at 1200 UTC on (left panel) 27 September, and (right panel) 4 October 2015.

Fig. 7. Experimental SPoRT-LIS total column relative soil moisture percentile product, valid at 1200 UTC on (left panel) 27 September, and (right panel) 4 October 2015.  Masked white areas represent water or urban pixels.

Read Full Post »

As mentioned in the previous post, we were concerned about the potential of organized thunderstorm outflow creating favorable conditions for blowing dust, as well as previous heavy rain activity increasing the potential for flash flooding in portions of Southeast Arizona yesterday (Sep 2) and today.  We have been trying to use LIS data as part of our process in determining the threat of both of these problems.  Yesterday was a mixed bag as I briefly outline below with less than full cooperation from the atmosphere.

Convective initiation occurred in locations we expected (similar to the WRF output posted previously), however we were unable to get the chain reaction of outflows that we hoped for.  We had problems in many valley locations (especially the Tucson Metro area) with early debris cloud and then anvils from early convection blocking solar insolation. We also underestimated the eastern extent of a modest low level drying trend filtering in from western Pima county.

Below is a loop of velocities with some observation and warning overlays early yesterday afternoon. The initial 45 kt outflow from the SVR southeast of Tucson attenuated rapidly as it approached Tucson.  Readings from Davis-Monthan AFB on the southeast side of Tucson at 2137Z showed a gust out of the SE at 30kts, and shortly later Tucson International Airport (a couple of miles further west) registered 23 kts.  By the time the outflow was west of Tucson it was difficult to detect.  There was no additional activity along this outflow in Pima County and it certainly wasn’t strong enough on it’s own to generate any dust problems by the time it got to areas we were concerned about.  The initial area that it started southeast of Tucson does have dust issues at times, but referring back to the soil moisture imagery from the previous post, things were pretty wet there.

sep2velsvr

It was an active day however.  Below is a composite post of the Severe Thunderstorm (yellow) and Flash Flood (green) products we issued yesterday.  When you compare to the 09z LIS output posted yesterday, the Flash Flood warnings were issued in an area with relative soil moistures above 70 percent (posted again for convenience).

severe and flash sep 2

soilmstrdusttue-20150902_090000

We once again have a favorable atmospheric profile for strong storms today (Sep 3), but with a little more convective inhibition to overcome and continuing issues with cloud cover.  We do have a stronger impulse embedded in the southwesterly flow that will push into our area late today and this evening.  Most standard and mesoscale model output (including latest UofA WRF and national HRRR) show increased coverage and organization of thunderstorm activity by late afternoon, especially west of Tucson.  This seems very reasonable, keeping the aforementioned caveats in mind.

A look at today’s LIS output shows that soil conditions are even more favorable in the areas of concern west and northwest of Tucson.  Especially in eastern Pinal and Maricopa counties with widespread values below 15 percent:

sep3mrnsoil-20150903_090000

Some of the special communications to our partners and the general public yesterday morning extended into mentions of issues for today as well.  We will adjust our weather story and social media posts to reflect the latest information, but our message is similar to yesterday.  We will again coordinate with Phoenix about any possible coordinated dust headline later this morning.  An example of the partner email we sent yesterday below:

BriefingUAPD09022015

Read Full Post »

We continue to use LIS data to increase our awareness of potential flood prone areas, as well as potential problems with convective dust storms.  An example below of interaction with the Phoenix office on 12Planet this morning where we discuss possible dust problems and inserting blowing dust in weather grids:

gfe-VB2

Below are this morning’s volumetric and relative soil moistures.  It highlights 2 concerns for us today.  The first is the area of heavy rain we saw 36 hours ago in the Tucson area and surrounding mountains is still very much reflected in soil moistures.  This will be one of the main areas of concern for potential flash flooding today.  The second concern is dust, with dry antecedent soil conditions a concern in favored blowing dust areas Pinal, Maricopa and central Pima counties.

soilmstrdusttue-20150902_090000

Finally, below is a look at the University of Arizona WRF-NAM 10m wind showing some very interesting convective outflows. The first generated around the Tucson area this afternoon from the strong potential of our atmospheric profile today, and the second southwest of Tucson after 00z from the influence of an impulse embedded in the moist southwesterly flow early this evening:

wrfnamwind1-20150902_200000

wrfnamwind2-20150902_210000

wrfnamwind3-20150902_220000

wrfnamwind4-20150903_020000

wrfnamwind5-20150903_030000

wrfnamwind6-20150903_040000

So that will be what we’re watching closely for today.  After a review of the 12z data, the day shift will coordinate with the Phoenix office on the possible issuance of an extended long fuse Blowing Dust Advisory.  We will also be issuing a partner coordination e-mail to local and state officials on this potential, and a heightened awareness weather story for the web site and social media.

Read Full Post »

Large wildfires during the heart of the southwest monsoon season are a fairly rare occurrence most years. Lightning sparked fires are typical in late June and early July before mainly dry thunderstorms transition to a wetter variety. These fires can be managed by land agencies while awaiting higher humidities to develop over the area.  July 2015 was a very wet month for much of New Mexico (10th wettest July), with the exception of northwestern New Mexico where near normal precipitation was observed. August turned much drier for many areas of the state as monsoon moisture and instability focused over Arizona. On August 19th, the Navajo River Fire broke out northwest of Dulce, NM, quickly growing to more than 1,000 acres by the 20th. The photo below taken by Bryon Odallac shows an established smoke plume emanating from the nearby higher terrain on August 20th.  The NASA SPoRT 0-10cm relative soil moisture imagery showed dry conditions coinciding with this same area of northwestern NM. The location of the wildfire is indicated by the “home” text. The 10-40cm relative soil moisture is also shown since it has been suggested that deeper layer soil moisture may better represent fuel conditions in more mature timber areas rather than the near surface duff layer. It is interesting to note that the 10-40cm layer values are actually wetter than the 0-10cm layer over much of this area. The two largest wildfires of the July to August monsoon period of 2015 have both occurred in these dry islands (see August 4, 2015 post on Fort Craig Wildfire).

Navajo River Fire captured by Bryon Odallac on August 20, 2015 near Dulce, NM.

Navajo River Fire captured by Bryon Odallac on August 20, 2015 near Dulce, NM.

 

NASA SPoRT LIS 0-10cm Relative Soil Moisture valid 00Z 21 Aug 2015.

 

NASA SPoRT LIS 10-40cm Relative Soil Moisture valid 00z 21 Aug 15.

NASA SPoRT LIS 10-40cm Relative Soil Moisture valid 00z 21 Aug 15.

Read Full Post »

NWS Albuquerque recently began ingesting the updated SPoRT CONUS LIS products in our new AWIPS II system as part of our continued collaboration with SPoRT. These products have already peaked the interest of several local, state, and federal partners. Short-term drought conditions have improved steadily since late winter as more frequent and widespread precipitation events impacted the state. Overall, deep-layer soil moisture conditions have improved substantially compared to this time last year (Fig. 1).

Figure 1. Deep soil moisture (0-200cm) 1-year change valid 12Z 27 July 2015.

Figure 1. Deep soil moisture (0-200cm) 1-year change valid 12Z 27 July 2015.

The SPoRT LIS products have become a valuable tool for drought monitoring during our monthly drought workshops. Several state and federal partners noted on our most recent call in late July that these new products provided an additional layer of situational awareness and infuse more science into the drought monitoring process. These products have also peaked the interest of our fire weather community, in particular Incident Meteorologist Brent Wachter. New Mexico during late July is generally under the influence of higher humidity with periodic wetting rainfall events. The convective nature of the precipitation however tends to bring about a patchwork of “have’s and have-nots”. The Fort Craig wildfire broke out in a dry pocket of south central Socorro County within the middle Rio Grande Valley during the afternoon of 26 July 2015. The New Mexico State Climatologist, Dave DuBois, captured the wildfire on camera and posted the image to Twitter shortly thereafter (Fig. 2).

Figure 2. A distant view of the Fort Craig wildfire captured by the New Mexico State Climatologist, Dave DuBois, around 830am, July 27, 2015.

Figure 2. A distant view of the Fort Craig wildfire captured by the New Mexico State Climatologist, Dave DuBois, around 830am, July 27, 2015.

The SPoRT LIS 0-10cm volumetric soil moisture at 12Z 28 July 2015 showed the corresponding dry area where the wildfire developed (Fig. 3). Les Owen from the New Mexico Department of Agriculture also noted this area of drying within Socorro County in what he called his “windshield survey” in mid to late July. The Fort Craig fire grew to nearly 700 acres over the course of two days. The NASA SPoRT soil moisture imagery showed the dry area quite well and the fire was located smack dab in the middle of it.

FIgure 3. NASA SPoRT 0-10cm relative soil moisture within south central Socorro County valid 12Z 28 July 2015. The location of the Fort Craig wildfire is indicated by the home identifier.

FIgure 3. NASA SPoRT 0-10cm volumetric soil moisture within Socorro County valid 12Z 28 July 2015. Note the large dry area in near surface soil moisture in response to the recent dry stretch. The location of the Fort Craig wildfire is indicated by the home identifier.

Several storms then impacted the area late on the 28th and the 29th leading to some natural fire suppression and reduction in active fire behavior. The follow-up SPoRT imagery at 12Z 30 July 2015 showed the increase in 0-10cm relative soil moisture over the same area (Fig. 4). The high resolution imagery could be useful in determining fuel dryness for potential fire starts from human activities, cloud to ground lightning ignitions, as well as highlight potential active fire behavior areas. We will continue to assess the possible applications of the SPoRT LIS products as we move through the remainder of the 2015 monsoon season.

Figure 4. NASA SPoRT 0-10cm relative soil moisture within Socorro County valid 12Z 30 July 2015. Note the dramatic increase in near surface soil moisture values in response to the active storm pattern. The location of the wildfire is noted by the home identifier.

Figure 4. NASA SPoRT 0-10cm relative soil moisture within Socorro County valid 12Z 30 July 2015. Note the dramatic increase in near surface soil moisture values in response to the active storm pattern. The location of the Fort Craig wildfire is indicated by the home identifier.

Read Full Post »

The inaugural Orion flight test successfully lifted off from Space Launch Complex 37 at Cape Canaveral Air Force Station aboard a Delta IV Heavy rocket the morning of 5 December (Fig. 1), following a scrubbed launch attempt the previous day. Orion is designed to take humans beyond Earth orbit into deep space, including missions to an asteroid and eventually Mars.

Fig 1. A Delta IV Heavy rocket lifts off from Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida carrying NASA's Orion spacecraft on an unpiloted flight test to Earth orbit. (photo credit: NASA)

Figure 1. A Delta IV Heavy rocket lifts off from Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida carrying NASA’s Orion spacecraft on an unpiloted flight test to Earth orbit. (photo credit: NASA)

The Applied Meteorology Unit (AMU) operated by ENSCO, Inc. at the Cape Canaveral Air Force Station, Florida has transitioned a high-resolution configuration of the Weather Research and Forecasting (WRF) numerical weather prediction (NWP) model to support ground and launch operations at the Eastern Range (ER) and Wallops Flight Facility (WFF). The AMU-WRF runs a nested modeling domain with the highest-resolution nest (1.33-km grid spacing) centered on the ER launch facility (Fig. 2) and uses two initialization datasets from NASA/SPoRT: (1) Land Information System soil moisture and soil temperature data, and (2) the high-resolution (2-km) northern hemispheric sea surface temperature product.

Figure 2.  Grid setup of the AMU-WRF model as transitioned into operations at the 45 WS.

Figure 2. Grid setup of the AMU-WRF model as used by the 45th Weather Squadron.

The ER and WFF require high-resolution numerical weather prediction model output to provide more accurate and timely forecasts of unique weather phenomena that can affect NASA’s Space Launch System, Launch Services Program, and Ground Systems Development and Operations Program daily operations and space-launch activities. Global and national-scale models cannot properly resolve important mesoscale features due to their horizontal resolutions being much too coarse.

Daily and weekly weather forecasts issued by the 45th Weather Squadron (45 WS) are used as decision tools for their day-to-day and launch operations at the ER. The 45 WS and vehicle Launch Weather Officer (LWO) use NWP models as a guide for these weather forecasts. Forecasters have found the AMU-WRF model performance quite useful. It has frequently been the preferred model to help accurately identify complex, small-scale boundary interactions. Of particular note, its rapid hourly update capability adjust to dynamic changes in weather features, aiding the LWO during sensitive ground and launch operations that require specific timing accuracy.

During the Orion launch operations on 4 and 5 December 2014, the LWO relied on AMU-WRF low-level wind, fog and precipitation output variables as part of their forecasts leading to a successful launch. Figures 3 and 4 show five-hour forecast AMU-WRF output of 10-m wind gust and forecast radar reflectivity as displayed in the AWIPS II at the 45 WS, valid at the beginning of the launch window (1200 UTC 5 December). The forecast radar reflectivity image (Fig. 4) suggested that the rain shower activity would be primarily south and west of the launch complex at the beginning of the launch window, which corresponded fairly well with the validating Melbourne, FL radar image in Figure 5. The combination of shower activity movement from northeast to southwest and little indication of forecast precipitation upwind of the launch complex suggested a favorable weather outcome for launch.

Figure 3.  AMU-WRF 5-hour forecast 10-m wind gusts as displayed in the 45 WS AWIPS II, valid 1200 UTC 5 December 2014 (7 am EST).

Figure 3. AMU-WRF 5-hour forecast 10-m wind gusts as displayed in the 45 WS AWIPS II, valid 1200 UTC 5 December 2014 (7 am EST).

Figure 4.  AMU-WRF 5-hour forecast radar reflectivity as displayed in the 45 WS AWIPS II, valid 1200 UTC 5 December 2014 (7 am EST).

Figure 4. AMU-WRF 5-hour forecast radar reflectivity as displayed in the 45 WS AWIPS II, valid 1200 UTC 5 December 2014 (7 am EST).

Figure 5.  Validating radar reflectivity at 1207 UTC 5 December 2014 (7:07 am EST), approximately corresponding to the time of the Orion launch aboard the Delta IV Heavy rocket.

Figure 5. Validating radar reflectivity at 1207 UTC 5 December 2014 (7:07 am EST), approximately corresponding to the time of the Orion launch aboard the Delta IV Heavy rocket.

Read Full Post »

We are in the third and final month of assessing SPoRT’s real-time version of LIS running the Noah land surface model. The assessment is being conducted at the NWS forecast offices in Huntsville, Houston, and Raleigh to determine the utility of SPoRT-LIS for monitoring drought and areal flooding potential. The past 1-2 weeks featured substantial rainfall that occurred over a large portion of the central and eastern U.S.  Much of this precipitation was associated with a deep trough that progressed from the Southern Plains to the U.S. East Coast from 13-16 October.  Fairly widespread rainfall amounts exceeding 5 inches occurred over portions of eastern Oklahoma, south-western Missouri, western Arkansas, and in a swath extending from southeastern Arkansas to the southern Appalachians (Fig. 1).

Fig 1.  Depiction of 7-day rainfall estimates from the Stage IV radar+gauge product, ending 1200 UTC 16 October 2014.

Figure 1. Depiction of 7-day rainfall estimates from the Stage IV radar+gauge product, ending 1200 UTC 16 October 2014.

One of the SPoRT-LIS fields that forecasters have found quite useful during the assessment is the one-week change in total column relative soil moisture (RSM, 0-2 m).  The RSM is the ratio of the current volumetric soil moisture between the wilting and saturation points for a given soil type, with values scaling between 0% (wilting) and 100% (saturation).  In response to the recent substantial rainfall over the Deep South, the LIS total column RSM increased by 8-24+% over a large area (Fig. 2) approximately corresponding to the areas that received 4 or more inches of rainfall in the past week given by the orange and red shading in Figure 1. This beneficial rainfall led to the improvement of the U.S. Drought Monitor classification by 1-2 classes over portions of Kansas, Oklahoma, Texas, extending into Alabama, Tennessee, and northern Georgia (Fig. 3).  The most recent U.S. Drought Monitor product issued on 14 October (Fig. 4) shows that all drought classes have been removed over northern Alabama, Tennessee, and Kentucky.

Fig 2.  SPoRT-LIS one-week change in total column (0-2 m) relative soil moisture valid 1200 UTC 16 October 2014.

Figure 2. SPoRT-LIS one-week change in total column (0-2 m) relative soil moisture valid 1200 UTC 16 October 2014.

Fig 4.  One-week change in the U.S. Drought Monitor classifications, from 7 to 14 October 2014.

Figure 3. One-week change in the U.S. Drought Monitor classifications, from 7 to 14 October 2014.

Fig 3.  U.S. Drought Monitor classification valid 14 October 2014.

Figure 4. U.S. Drought Monitor classification valid 14 October 2014.

Read Full Post »

Older Posts »

Follow

Get every new post delivered to your Inbox.

Join 1,518 other followers