Tuesday Update

Good Afternoon,

Here are a few highlights of what’s going on in the west today.

Water Supply

Current Stream Flows

We’ll start off with a peak at the Stream Flow Summary page that offers a high level view of how elevation levels compare historically.  A couple weekly changes stand out immediately; Grand Coulee dropped 9.7 feet in a week, and Dworshak decreased 6.7 feet.

Historical Reservoir Levels

The sharp elevation decrease starting at the beginning of February has brought Grand Coulee to almost the exact same elevation seen on March 6th last year, and within a couple feet of 2015 as well.

Hydro Rivers Summary

The Mid-C River Summary supports the elevation changes mentioned above by showing that the largest annual increase in CFS are taking place in the Columbia and Snake.  The Pend Oreille – at Albeni Falls also had a large annual change with an increase of 7,700 CFS year-over-year.

Hydro Rivers Historical

Though Pend Oreille – at Albeni Falls has a high year-over-year increase,the historical chart illustrates how much more it can rise.  The next couple weeks have historically been the beginning of a large increase in CFS, though the 2017 winter suggests it may not come that early.

Precipitation Summary

There isn’t much precipitation in the West’s 10 day forecast, at least not much to add to any of the aforementioned rivers.  A handful of stations are expecting a precipitation anomaly of more than 0″, and the largest (Billings) is still just 0.72″.  NP15 looks like the driest hub for the time being as each of it’s measured stations will be more than 3/4″ drier than normal.

NW River Forecast Center

The 1–Day River Forecast is expecting just shy of 1000 MW higher than the STP forecast for March 7th, though even that number marks the low point over the following 10 days.  This week is expected to peak on the 10th at 19,155 MW.


Mid-C Loads

Mid-C week-over-week loads fell just over 1,000 MW by yesterday. Loads decreased daily beginning last Monday until again increasing on Sunday.  Year-over-year demand remains elevated from last year as yesterday finished with a peak of more than 2800 MW higher than 2016.

SP-15 Loads

SP15 demand is also down more than 1000 MW week-over-week, but unlike Mid-C, loads are also down annually (466 MW difference as of yesterday).


Current Weather Summary

Most hubs are projecting warmer than normal weather across the west, especially in Denver and other stations near the Rockies.  Mid-C is the exception to the warm up as everything west of the Rockies should expect to be cooler than normal.  The 2017 winter isn’t showing many signs of leaving the Northwest.

Denver Temps

Denver will hover close to 10 degrees above normal maximum temperatures for at least the next week.  The high of 69 expected on the 9th will mark a full 13 degrees above normal.

Denver’s minimum temps are showing similar patterns, though maybe even a bit more extreme.  The low temp on the 10th could be 16 degrees above normal as early spring conditions settle in the Rockies.

NP-15 Temps

Not as exciting as Denver, but NP-15 should have at least a week long spell of above normal minimum temperatures with a peak on the 12th at 7 degrees above normal.  Precipitation is likely to hold off until early into next week when there could be a few consecutive days of decent precip.


ISO Major Unit Outages Chart

Gas outages have continues to increase since the beginning of March and now sit at 4768 MW, a jump of more than 2100 MW since the 1st.  Wind outages have also increased in the same span of time, moving from 44 MW to more than 200 MW, the largest non-gas increase.

Natural Gas

Natural Gas – Demand Summary

Week-over-week demand is up in Mid-C, NP15, and SP15.  Mid-C and SP15 both saw large increases of more than 140 MMCF.  Despite the weekly increase, SP15 remains more than 800 MMCF below two weeks ago.


Transmission Mid-C to NP

TTC dropped to 2400 (from 3300) on the 4th, and recovered by mid-day of the 5th.  Peak flow dropped accordingly in the same span, reaching a high of just 2145 MW, 700 MW lower than a day before and after the TTC decrease.  Since TTC increased back to 3300, flow hit a peak of 2898 MW late last night.

Transmission – MidC to BC

There was little variance in daily flow average for most of last week though yesterday marked a slight change as flow hit its lowest daily average in more than a week (51 MW).  TTC had a six hour decrease on the 3rd with a decrease of 400 MW.  Flow reached a peak of 1892 early yesterday.


Have a great week,