September 20, 2019 Weather Impacts On Economic Activity – Corn, Soybean And Cotton Forecasts.

Written by Sig Silber

Updated at 5:20 p.m. September 20, 2019 to reflect the updated Week 3 – 4 Forecast

Each week we report on the current status of the crop and once a month, or as the data comes in, we report on the forecast of the final seasonal results. This week we have additional information on corn, soybeans, cotton, and California Navel Oranges. Of course, we always present the weekly drought report and this week we have a new Seasonal Drought Forecast. We feature Australia a bit as they are having a bad drought. And we have many other regular drought-related indices we report on including wildfires and floods and soil conditions. We also provide a shortened version of the Intermediate-term weather forecast.

Please share this article – Go to the very top of the page, right-hand side, for social media buttons. Please feel free to send this article to anyone who you think might benefit from reading it.

A review of Drought over the last twelve months.

Let us focus on one year of change.

Australia Drought Bites (H/T Nick Proferes)

CONUS Soil Conditions

And shifting to the Alaska and CONUS Weather Forecast

First Temperature

And then Precipitation

Here is the discussion which was issued with the Week 3 – 4 Forecast.

Week 3-4 Forecast Discussion Valid Sat Oct 05 2019-Fri Oct 18 2019

The Week 3-4 Outlook was based primarily on dynamical model forecasts from the ECMWF, CFS, and JMA operational ensembles and the Subseasonal Experiment (SubX) multi-model ensemble (MME). Progression of dynamical model forecasts from the week 2 period was also considered. Additional guidance from a multivariate linear regression (MLR) statistical forecast, based on the state of ENSO, MJO and decadal trends, was considered, as well as an automated blend of operational dynamical models and the MLR statistical model. The MJO is active over the Western Hemisphere, and dynamical model forecasts generally indicate the potential for progression of the convective signal eastward over the next couple weeks. ENSO neutral conditions persist over the tropical Pacific, and is not a factor in the Week 3-4 Outlook.

Most dynamical model forecasts generally persist the mid-level circulation pattern forecast for the week 2 period into weeks 3 and 4, with some de-amplification of 500-hPa height anomalies. Above normal 500-hPa heights are predicted across the Aleutian Islands into the western Gulf of Alaska. Above normal 500-hPa heights are also forecast over the southern-central and eastern CONUS. Troughing and a weakness in positive 500-hPa height anomalies or negative anomalies are predicted over the northwestern CONUS. There is general agreement for this predicted circulation pattern among the ECMWF, CFS, GEFS and ECCC ensembles, and the SubX MME.

While there is good agreement among the ensemble mean height forecasts from the various models, there are some clear differences among the models on the temperature forecast for the week 3-4 period. The ECMWF ensemble predicts high probabilities of below normal temperatures over the Northwest and high probabilities of above normal temperatures over the Southeast, associated with the predicted trough and ridge over the western and eastern CONUS. The SubX MME probabilistic forecast, including the CFS,indicates greater probabilities for below normal temperatures from the Southern and Central Plains into the Upper Mississippi Valley, due to weakening of the predicted trough over the west in dynamical model forecasts from week 2 to week 4, and increased chances of precipitation over this region. The Week 3-4 Outlook combines the SubX MME probabilistic temperature forecasts with an equal weighted consolidation of calibrated temperature forecasts from the ECMWF, CFS and JMA ensembles.

Enhanced probabilities for below normal temperatures are indicated in the Week 3-4 Outlook over much of the Northwest away from the Pacific Coast, largely supported by the ECMWF ensemble model forecasts. Probabilities of below normal temperatures are elevated above 50 percent across northern North Dakota into the Upper Mississippi Valley and western Great Lakes Region, as well as northern Maine, as indicated by the consolidation of the ECMWF, CFS and JMA forecasts and further supported by the SubX MME. Above normal temperatures are more likely along the Pacific Coast of the CONUS, under onshore flow with above normal sea surface temperatures near the coast, as indicated by the SubX MME. Above normal temperatures are also likely from Southern California and the Southwest region into the western Central and Southern Plains, under anomalous southerly flow. Above normal temperatures are most likely from the Southeast to the Mid-Atlantic and southern New England states, under predicted above normal 500-hPa heights. Above normal sea surface temperatures in the Bering Sea and predicted ridging over the Aleutian Islands leads to elevated probabilities of above normal temperatures for most of Alaska, with the exception of the eastern interior regions of the state.

The precipitation outlook for the week 3-4 period presented several challenges, as variations among the ECMWF, CFS and JMA operational ensembles and among the constituent models of the SubX indicate uncertainty following the week 2 period. Most models generally predict tropical activity and potential tropical cyclones over the Gulf of Mexico, with atmospheric moisture flowing northward into the western Gulf and parts of the Southwest CONUS, around the predicted positive 500-hPa height anomaly over the eastern CONUS, leading to enhanced probabilities of above median precipitation along the Gulf Coast and northward into western Texas and eastern areas of the Southwest in the Week 3-4 Outlook. Some ensemble models indicate flow of moisture northeastward from the Gulf along the south Atlantic Coast elevating the probabilities of above normal precipitation in the outlook. Below normal precipitation is more likely for inland areas of the Southeast, as indicated by the ECMWF, CFS and JMA ensemble model forecasts, and the SubX MME consensus with some disagreement among constituent models. Below normal precipitation is also indicated for Oregon and parts of the Northwest, where dynamical models are in general agreement. Probabilities of above normal precipitation are increased from the Northern Plains into the Upper Mississippi Valley and western Great Lakes region, as indicated by the ECMWF ensemble and the SubX MME forecasts. Equal chances of above and below median precipitation is indicated elsewhere over the CONUS in the Week 3-4 Outlook in regions where there is greater spread and uncertainty among dynamical models. Above median precipitation is likely for areas of western Alaska, due to onshore flow ahead of anomalous above normal sea surface temperatures. Some dynamical models indicate an elevated probability of above median precipitation for the Alaska Panhandle with enhanced inland moisture flow from the North Pacific.

Sea surface temperatures are forecast to remain above normal around Hawaii, which should lead to above normal temperature and precipitation for the week 3-4 period.

Concluding remarks

Current Drought Conditions

Now we take a look at Thursday’s U.S. Drought Monitor Report.

The U.S. Drought Monitor is a comprehensive way of understanding the drought situation for the U.S. It is issued every Thursday and reflects the conditions as of the prior Tuesday. Drought is defined as a moisture deficit bad enough to have social, environmental or economic effects. Thus, more factors than recent precipitation are considered and more information on how it is done is found at the end of this report.

U.S. Affiliated Pacific Islands and the U.S. Virgin Islands.

Below is the map for just CONUS.

Last Week	This Week

Some might find this animation of twelve weeks of change useful;

The graphic below shows the one-week change in drought intensity. Yellow is bad. Green is good.

Now we show the week to week change information by region. The yellow is where the level of drought has been raised. The green is where the level of drought has been lowered.

Deterioration in Kansas, Improvement in North Dakota.

Improvement to the north and deterioration to the south.

General deterioration. There were three centers where it was worse: West Virginia, an area that could be described as a circle centered on Delaware, and Vermont/SW Maine.

Mostly deterioration but parts of Texas especially southern Texas improved.

General deterioration but with respect to Florida it was only northern Florida.

Arizona is the focus of the deterioration. There was improvement in Oregon and Washington and also southern Idaho and northern Utah.

Here is the Discussion that was issued with the Drought Report.

This Week’s Drought Summary

Rapidly intensifying “flash drought” – attributed in part to extreme late-summer heat – continued to afflict many areas from the lower Midwest and Mid-Atlantic States to the Gulf Coast. Likewise, an abysmal Southwestern monsoon (to-date) led to increasing drought intensity and coverage in Arizona, while short-term drought persisted across the Hawaiian Islands. Conversely, moderate to heavy rain eased or alleviated dryness and drought from the Great Lakes into the Northwest as well as in southwestern Alaska and southern Puerto Rico.

Northeast

Early-week heat (temperatures as high as the lower 90s) and locally acute short-term rainfall deficits (30-day rainfall totaling 10 to 25 percent of normal) led to the expansion of D0 (Abnormal Dryness) across West Virginia, Maryland, Delaware, as well as southeastern Pennsylvania and the southern two-thirds of New Jersey. Similar pockets of Abnormal Dryness were noted in southern New England.

Southeast

Intense late-summer heat and acute short-term dryness led to a sharp increase in drought intensity and coverage. Excessive heat (95-101°F) and pronounced short-term rainfall deficits (30-day rainfall totaling less than 25 percent of normal) heightened evapotranspiration rates and soil moisture losses, resulting in quickly escalating drought impacts (often referred to as a “flash drought”.) It should be noted that “flash drought” often occurs more quickly (in terms of impacts) than the data indicates. For this weeks’ analysis, the expansion of D0 (Abnormal Dryness) and Moderate Drought (D1) was driven by guidance from local experts, impact reports from observers, as well as temperature- and rainfall-driven data products which focused on the past 30 to 60 days. Increases in D0 and D1 were most pronounced in northern portions of the region (from northern Alabama into central North Carolina) as well as from the Florida Panhandle into southern Georgia. State-wide average topsoil moisture was rated 73 percent short to very short (according to USDA-NASS) as of September 15 in both Georgia and Alabama, and 83 percent short to very short in Virginia.

South

As with the Southeast, intense late-summer heat and acute short-term dryness led to a sharp increase in drought intensity and coverage across central portions of the region. Excessive heat (95-102°F) and pronounced short-term rainfall deficits (30-day rainfall totaling locally less than 10 percent of normal) heightened evapotranspiration rates and soil moisture losses, resulting in quickly escalating drought impacts (often referred to as a “flash drought”.) It should be noted that “flash drought” often occurs more quickly (in terms of impacts) than the data indicates. In terms of temperatures, Wednesday, September 18th marked the 18th consecutive day of 90-degree heat at Little Rock, Arkansas (the long term historical total-September average is 9 days); September 18th also marked the 7th day with 100-degree readings at Meridian, Mississippi (only one other year – 1980 – had this many, and only 7 other years total had 3 or more (records dating back to 1889)). For this weeks’ analysis, the expansion of D0 (Abnormal Dryness) as well as Moderate (D1) to Extreme Drought (D3) was driven by guidance from local experts, impact reports from observers, as well as temperature- and rainfall-driven data products which focused on the past 30 to 60 days. Increases in drought were most pronounced from central and northeastern Texas into the central and northern Mississippi Delta, where 60-day rainfall has totaled a meager 25 percent of normal or less. State-wide average topsoil moisture was rated more than 70 percent short to very short (according to USDA-NASS) as of September 15 in the Mississippi Delta States, and 83 percent poor to very poor in Texas (tied for second highest in the nation with Virginia, only 2 percentage points behind California’s 85 percent). Despite the generally dry, hot weather pattern, heavy showers and thunderstorms (2-4 inches) provided highly localized drought relief across southeastern and north-central Texas as well as western Oklahoma. After the end of the monitoring period (12z Tuesday), heavy showers associated with the remnants of Tropical Storm Imelda were bringing rain to southeastern Texas; the impacts of this rainfall will be incorporated in next week’s U.S. Drought Monitor.

Midwest

Reductions to drought intensity and coverage across the northern half of the region contrasted with rapidly intensifying and expanding drought in the south. From Minnesota and northern Iowa into Wisconsin, Michigan, and northern Illinois, widespread soaking rainfall (1-6 inches, locally more than 8 inches) eased or eradicated lingering Abnormal Dryness (D0) and Moderate Drought (D1). Conversely, temperatures in the middle and upper 90s coupled with acute short-term moisture deficits (30-day rainfall locally less than 25 percent of normal) led to an expansion of D0 and D1, most notably from southern Illinois eastward into Kentucky and neighboring portions of Indiana and Ohio. State-wide average topsoil moisture was rated more than 40 percent short to very short (according to USDA-NASS) as of September 15 in Indiana and Ohio, and 78 percent poor to very poor in Kentucky. Reports from the field indicate Kentucky is experiencing the same type of “flash drought” being observed across much of the south; the impacts of “flash drought” often occur more quickly than the objective data indicates.

High Plains

Widespread moderate to heavy rain (1-6 inches, locally more than 8 inches) over the northern half of the region contrasted with pockets of dryness and drought in the southern and western High Plains Region. The rain eliminated the last vestiges of Abnormal Dryness (D0) in North Dakota and eastern Nebraska. Conversely, input from local experts as well as 60-day rainfall locally less than 50 percent of normal led to a minor expansion of D0 and Moderate Drought (D1) in southwestern Kansas. The rest of the region remained unchanged and largely devoid of dryness concerns, though D0 and D1 remained in place over western and southeastern portions of Colorado as well as southwestern Wyoming.

West

An abysmal Southwestern monsoon contrasted with increasingly wet weather in the Northwest. The Southwestern monsoon, which typically runs from June 15-September 30 and accounts for up to half the total annual precipitation in some parts of the Southwest, has featured less than 50 percent-of-normal rainfall (locally less than 30 percent). While showers over the past week in New Mexico (1-3 inches, locally more) helped stem the recent trend toward increasing drought in the east, rain bypassed most of Arizona. Input from local experts as well as mounting 6-month rainfall deficits supported an expansion of Severe Drought (D2) in the driest locales of southern and central Arizona.

Farther north, moderate to heavy rain fell for a second consecutive week from the Pacific Northwest into the northern Rockies, with the highest totals (2 inches or more) observed on the windward slopes of the mountains. This pushed two-week totals to locally more than 4 inches, spurring additional reductions of Abnormal Dryness (D0) as well as Moderate to Severe Drought (D1-D2). Reductions to D0 in the eastern Great Basin were spurred by input from local experts, who indicated a lack of any lingering impacts due to a recent uptick in precipitation in northeastern Utah (locally more than 2 inches over the past two weeks).

Alaska, Hawaii, and Puerto Rico

The recent trend toward wetter weather continued in Alaska, with this past week featuring 1 to 4 inches of rain over many of the state’s primary drought areas. 7-day rainfall totaled as much as 3.5 inches and 4.2 inches on the Alaska and Kenai Peninsulas, respectively, with two-week rainfall in excess of 6 inches locally. While more rain will be needed to fully eradicate the Alaska’s Moderate to Extreme Drought (D1-D3), the recent wet weather has eased the drought coverage and intensity somewhat. In Hawaii, portions of the Big Island and Maui remained very dry. Reports from the field indicated many pastures aren’t usable despite enough rain recently to encourage green up. In Puerto Rico, heavy rain during the past week (2-6 inches, locally more) continued to eat away at the northern edge of the island’s southern drought areas, though steamflows remained very low (below the 10th percentile) along the south coast of Puerto Rico.

Pacific Islands

Short-term abnormal dryness continued this week in American Samoa. At Pago Pago, 0.53 inches of rain fell, bringing the monthly total to 1.78 inches. At Siufaga Ridge, 1.03 inches fell, and 0.44 inches fell at Toa Ridge.

No dryness is taking place in Palau, where 6.87 inches of rain has fallen in September so far, which is already above the 5.9-inch normal for the month.

In Saipan, 6.31 inches of rain fell on Sept. 16, so no dryness is occurring there. On Rota, the last three weeks and months have received rainfall well above their respective cutoffs; 8.24 inches of rain fell there this week, with one day of data missing, bringing the September total to 12.3 inches. The last three weeks and months in Guam have also received sufficient precipitation, where weekly rainfall was 9.23 inches (with one missing day), which brought the monthly total to 13.09 inches.

Conditions over the last month and a half on Yap have been sufficiently wet; 11.58 inches of rain fell in August, and with 5 missing days of data this week, 4.7 inches of rain had fallen so far in September. Sufficient rainfall in August and during two of the last three weeks on Woleai maintained wet conditions there, though five days of data were missing this week. Data in Fananu was missing this week, but non-drought conditions continued here, given the 20.33 inches of rain in August and 10.33 inches of rain in September. Only 0.83 of rain has fallen at Chuuk Lagoon this week, with one day of missing data, but 13.99 inches of rain has already fallen in September. In Lukunor, sufficient rainfall from June to August and three of the last four weeks maintained a lack of dryness here. Two days of data were missing from Nukuoro this week, where 0.6 inches of rain had fallen, but August had 13.77 inches of rain and September has reached 4.02 inches. No rain was recorded through five recorded days this week on Kapingamarangi, but 5.04 inches so far in September precluded a change to short-term abnormal dryness. Rainfall on Pohnpei has been high on most recent time scales, where 7.34 inches of rain has fallen this week (with two days of missing data). Short-term dryness on Pingelap improved to normal conditions this week; 3.5 inches of rain (with two days missing) combined with 7.8 inches of rain in September sufficiently improved the drier short-term conditions. Rainfall on Kosrae continued to be sufficient, with 2.78 inches of rain this week (with two missing days) and 9.73 inches through September. Missing data in Ulithi precluded assigning a drought depiction there this week.

In Kwajalein, sufficient rainfall in August, combined with 2.56 inches of rain this week and 6.04 inches through September combined to continue normal conditions there. In Ailinglapalap, a few recent weeks have received below threshold rainfall, but August received sufficient rainfall and 4.35 inches of rain has fallen so far in September, so normal conditions continued here this week. On Jaluit, severe drought continued on both the short- and long-term; 0.55 inches of rain had fallen so far (with two days of missing data this week), bringing the September total to 2.76 inches. Abnormally dry long-term conditions continued on Utirik, where most months from November 2018 to July 2019 received less than half of their rainfall thresholds, but where rainfall in August and September has been higher. Short- and long-term moderate drought continued on Wotje, where January-June monthly precipitation totals all fell below half of their respective thresholds, and 0.94 inches of rain fell this week. Normal conditions continued on Majuro this week, where 3.33 inches of rain fell this week. 0.67 inches of rain fell in Mili this week (with two days of missing data), leaving September totals at 3.55 inches. However, the 16.27 inches of rain in August precluded the development of abnormally dry conditions here.

Virgin Islands

Abnormal dryness continued this week on St. Croix, where a blend of one- to 12-month SPI suggested long-term abnormally dry conditions. Less rain fell this week in St. Thomas, but abnormal dryness was not occurring there.

Looking Ahead

An active weather pattern will foster periods of moderate to heavy rainfall from the southern Plains into the Midwest, while intermittent rain and mountain snow linger from the Pacific Northwest into the northern Rockies. Meanwhile, moisture associated with the remnants of Tropical Storm Imelda will fuel locally heavy showers in southeastern Texas and the western Delta. Some late-season monsoon showers are also possible in the Four Corners Region, though the heaviest rain may stay east of the region. Despite the stormy weather pattern, little – if any – rain is expected across the Southeast, with only light showers in the offing farther north in the Mid-Atlantic and Northeastern States. The NWS 6- to 10-day outlook for September 24 – 29 calls for above-normal temperatures along the central California Coast and from the Rockies to the East Coast; cooler-than-normal weather will be confined to the Northwest and lower Southwest. Near- to above-normal precipitation across much of the nation will contrast with drier-than-normal conditions from the Southeast into the Mid-Atlantic States.

Some may find this way of looking at things useful and I hope these graphics are not too small to read. I did not make them so you could click on them individually but you can click on the whole graphic and it may enlarge. But I think you get the picture. It has been a rapid onset and demise. When you read these graphics, remember that the older graphics are not the drought conditions that existed then but the change from then until now.

Let’s focus on the change between August 13, 2019 through September 10, 2019 i.e. a month. .

Drought Forecasts

First, we show the forecast through December which was issued on September 19, 2019 (to be updated on October 18, 2019). These two forecasts are issued by the same agency but to obtain them you need to access two different links here and here.

Here is the Three-Month Forecast which was issued on September 19, 2019

Here is the discussion that was issued with the new forecast.

Latest Seasonal Assessment – A hot end to the summer along with a generally suppressed convective regime resulted in numerous areas of drought development across the southern Plains, Midwest and Southeast, while spotty convection brought some relief to the areas where rainfall occurred. Larger regions of degradation spread across the Four Corners states. In contrast, above-median precipitation brought drought relief to parts of the Pacific Northwest, Northern Rockies, and Northern Plains. The October-December period typically offers an opportunity for soil moisture recharge as evapotranspiration rates decline. The window for monsoonal moisture across the Southwest closes, while the West Coast wet season begins to ramp up. Climatological precipitation drops off rapidly across the central U.S. and the extreme Southeast, while remaining fairly steady across the eastern Corn Belt and Northeast. With no ENSO forcing anticipated during the next several months, the CPC monthly and seasonal outlooks were based primarily on a consensus of the dynamical and statistical model guidance as well as long term temperature and precipitation trends. Hot, mostly dry weather is anticipated to continue for the next several weeks across much of the East, increasing the potential for rapid expansion of short-term drought from southeastern Pennsylvania and southern New Jersey southward to the Florida Peninsula. Longer range forecasts show enhanced chances for above-median precipitation across the south- and mid-Atlantic states, which would ease drought conditions that do develop. Therefore, drought development favored to persist through the end of December is indicated on this outlook extending from eastern Alabama through the central Appalachians. Further west, drought persistence is favored for much of the Southwest and southern Plains as climatological precipitation declines, with slow expansion possible across central Texas. Above-median precipitation favored in both short and long term guidance favors drought relief for southern Arizona, while near-term impacts from the remnants of Tropical Storm Imelda favor widespread reduction of drought across eastern Texas, southeastern Oklahoma, and the lower Mississippi River Valley. The continuation of enhanced moisture into the Northwest followed by the onset of the wet season favors a continuation of drought reduction, while a wet end to September followed by the Autumn recharge season may bring relief to the Midwest and Great Lakes states. Across Alaska, drought relief is anticipated along and east of the Kenai Peninsula, while enhanced tropical moisture favors gradual drought reduction for Hawaii ahead of the main wet season. Drought persistence is favored for Puerto Rico, but uncertainty is high as the Atlantic tropical cyclone season continues.

Here is the Monthly Drought Outlook which was updated on August 31, 2019

Floods remain a concern but only in a limited area.

Let’s see if this animation works. It shows the pattern for August.

Active Major Fires

Current Wildfire Risk

Click here to update. Red is high risk, blue is low risk. This graphic updates daily but you have to click on the link provided to get the updates More information can be found here.

This explains the model a bit.

Looking out another month.

Crop Progress

Recently, we looked at the individual crop progress reports graphically from this source. Also recently we reviewed this Executive Summary Report which provides projections of the ultimate harvest. It is important to make the distinction between crop progress which we report in this section of our article weekly and forecasts of what the result for the crop will ultimately be and we review that information as the NASS forecasts are released. One a month they issue a briefing document on the situation.

Now, we will look at the season to date information summary. So that is a crop progress report, not a forecast.

The following table summarizes the situation. It has changed just a bit since last week for cotton.

This provides some additional information: There are many factors that have led to the current situation but one is the amount of sunshine other causes of temperature and it has been inadequate.

Side by Side

International

A map helps and is not always available and fortunately, it was not available this week.

Major Sources of Information

In the box are shown the major resources we use. We will not be using them all each week but the reader is welcome to refer to these resources.

Background Information

The sequence of drought occurrence and impacts for commonly accepted drought types. All droughts originate from a deficiency of precipitation or meteorological drought but other types of drought and impacts cascade from this deficiency. (Source: NDMC)

Source: National Drought Mitigation Center, University of Nebraska-Lincoln