diff --git a/workflow/CROW b/workflow/CROW
index 6065439cc6..2079a68118 160000
--- a/workflow/CROW
+++ b/workflow/CROW
@@ -1 +1 @@
-Subproject commit 6065439cc6bbffa61d5551dd8215877e3322d3e0
+Subproject commit 2079a681188ea49ad73f548de093216c828e8750
diff --git a/workflow/cases/aerosol_firex_forecast.yaml b/workflow/cases/aerosol_firex_forecast.yaml
index 4a881d2592..ee8e96b8c7 100644
--- a/workflow/cases/aerosol_firex_forecast.yaml
+++ b/workflow/cases/aerosol_firex_forecast.yaml
@@ -11,10 +11,10 @@ case:
   settings: 
     SDATE: 2019-07-01t00:00:00
     EDATE: 2019-07-15t00:00:00
+    STEP_GFS: !timedelta "24:00:00"
+    STEP_DA: !timedelta "00:00:00"
     max_job_tries: 1
 
-    gfs_cyc: 1
-
     cplgocart: .true.
     print_esmf: .true.
     nems_temp: 'atm_aer'
diff --git a/workflow/cases/aerosol_free_forecast.yaml b/workflow/cases/aerosol_free_forecast.yaml
index 28923dd2c7..0c13067cfb 100644
--- a/workflow/cases/aerosol_free_forecast.yaml
+++ b/workflow/cases/aerosol_free_forecast.yaml
@@ -4,8 +4,11 @@ case:
 
   settings: 
     SDATE: 2013-04-01t00:00:00
-    EDATE: 2013-04-01t00:00:00
+    EDATE: 2013-04-02t00:00:00    
+    STEP_GFS: !timedelta "24:00:00"
+    STEP_DA: !timedelta "00:00:00"
     max_job_tries: 1
+    rocoto_cycle_throttle: 1
 
     cplgocart: .true.
     print_esmf: .true.
@@ -35,12 +38,12 @@ case:
     LEVS: 65
     DELTIM: 450
     layout:
-       x: 6
-       y: 8
-       nth: 1
-       WGRP: 1
-       WGRP_NTASKS: 24
-       WRTIOBUF: "32M"
+      x: 6
+      y: 8
+      nth: 1
+      WGRP: 1
+      WGRP_NTASKS: 24
+      WRTIOBUF: "32M"
 
   chem_settings:
     MOD: gsdchem
@@ -55,3 +58,6 @@ case:
   post:
     downset: 2
     GOESF: no
+
+  archiving:
+    archive_to_hpss: False
diff --git a/workflow/cases/atm_free_forecast.yaml b/workflow/cases/atm_free_forecast.yaml
index 600e069044..719b6bda0f 100644
--- a/workflow/cases/atm_free_forecast.yaml
+++ b/workflow/cases/atm_free_forecast.yaml
@@ -6,6 +6,8 @@ case:
   settings: 
     SDATE: 2013-04-01t00:00:00
     EDATE: 2013-04-01t00:00:00
+    STEP_GFS: !timedelta "24:00:00"
+    STEP_DA: !timedelta "00:00:00"
 
     cplflx: .false.
     print_esmf: .true.
diff --git a/workflow/cases/coupled_free_forecast.yaml b/workflow/cases/coupled_free_forecast.yaml
index 2e31e51a14..f7c6e0e39f 100644
--- a/workflow/cases/coupled_free_forecast.yaml
+++ b/workflow/cases/coupled_free_forecast.yaml
@@ -5,6 +5,8 @@ case:
   settings: 
     SDATE: 2013-04-01t00:00:00
     EDATE: 2013-04-01t00:00:00
+    STEP_GFS: !timedelta "24:00:00"
+    STEP_DA: !timedelta "00:00:00"
 
     onestep: .true.
     cplmode: nems_frac
diff --git a/workflow/cases/coupled_free_forecast_nofrac_wave.yaml b/workflow/cases/coupled_free_forecast_nofrac_wave.yaml
index 161708b483..fca4453777 100644
--- a/workflow/cases/coupled_free_forecast_nofrac_wave.yaml
+++ b/workflow/cases/coupled_free_forecast_nofrac_wave.yaml
@@ -5,6 +5,8 @@ case:
   settings: 
     SDATE: 2013-04-01t00:00:00
     EDATE: 2013-04-01t00:00:00
+    STEP_GFS: !timedelta "24:00:00"
+    STEP_DA: !timedelta "00:00:00"
 
     onestep: .true.
     cplmode: nems_orig
diff --git a/workflow/cases/coupled_free_forecast_wave.yaml b/workflow/cases/coupled_free_forecast_wave.yaml
index 72b96eee1e..acf39609da 100644
--- a/workflow/cases/coupled_free_forecast_wave.yaml
+++ b/workflow/cases/coupled_free_forecast_wave.yaml
@@ -5,6 +5,8 @@ case:
   settings: 
     SDATE: 2013-04-01t00:00:00
     EDATE: 2013-04-01t00:00:00
+    STEP_GFS: !timedelta "24:00:00"
+    STEP_DA: !timedelta "00:00:00"
 
     onestep: .true.
     cplmode: nems_frac
diff --git a/workflow/cases/dev/Run-From-HPSS-ICs.yaml b/workflow/cases/dev/Run-From-HPSS-ICs.yaml
index 9627d778b6..88cb6d0bc6 100644
--- a/workflow/cases/dev/Run-From-HPSS-ICs.yaml
+++ b/workflow/cases/dev/Run-From-HPSS-ICs.yaml
@@ -57,10 +57,7 @@ case:
     # files instead.
     chgres_and_convert_ics: yes
 
-    # gfs_cyc: this setting is used in a full data assimilation cycled
-    # workflow to only run the GFS every N cycles.  Keep this at "4" to
-    # ensure it is run every cycle.  
-    gfs_cyc: 4
+    STEP_GFS: !timedelta "06:00:00"
 
   places:
     # workflow_file: which workflow we're running.  This specifies the
diff --git a/workflow/cases/dev/ecrealtime-prfv3rt1_GFS@C768_ENKF@384+80MEM-Dell.yaml b/workflow/cases/dev/ecrealtime-prfv3rt1_GFS@C768_ENKF@384+80MEM-Dell.yaml
index 0541c3cf45..a46525e4c6 100644
--- a/workflow/cases/dev/ecrealtime-prfv3rt1_GFS@C768_ENKF@384+80MEM-Dell.yaml
+++ b/workflow/cases/dev/ecrealtime-prfv3rt1_GFS@C768_ENKF@384+80MEM-Dell.yaml
@@ -136,5 +136,5 @@ case:
     EDATE: 2018-08-30t18:00:00
     chgres_and_convert_ics: No
     realtime: true
-    gfs_cyc: 4
+    STEP_GFS: !timedelta "06:00:00"
     run_gsi: Yes
diff --git a/workflow/cases/dev/four_cycle_mode_prfv3rt1_GFS@C768_ENKF@384+80MEM-Dell.yaml b/workflow/cases/dev/four_cycle_mode_prfv3rt1_GFS@C768_ENKF@384+80MEM-Dell.yaml
index d25582577d..0b010d8c63 100644
--- a/workflow/cases/dev/four_cycle_mode_prfv3rt1_GFS@C768_ENKF@384+80MEM-Dell.yaml
+++ b/workflow/cases/dev/four_cycle_mode_prfv3rt1_GFS@C768_ENKF@384+80MEM-Dell.yaml
@@ -141,7 +141,7 @@ case:
     EDATE: 2018-08-10t18:00:00
     chgres_and_convert_ics: No
     realtime: true
-    gfs_cyc: 4
+    STEP_GFS: !timedelta "06:00:00"
     run_gsi: Yes
 
   schedvar:
diff --git a/workflow/cases/dev/fv3q2fy19retro5-GFS@C768_ENKF@384+80MEM-Dell.yaml b/workflow/cases/dev/fv3q2fy19retro5-GFS@C768_ENKF@384+80MEM-Dell.yaml
index a3f89871f3..b52f5a67fc 100644
--- a/workflow/cases/dev/fv3q2fy19retro5-GFS@C768_ENKF@384+80MEM-Dell.yaml
+++ b/workflow/cases/dev/fv3q2fy19retro5-GFS@C768_ENKF@384+80MEM-Dell.yaml
@@ -134,5 +134,5 @@ case:
     EDATE: 2016-04-18t12:00:00
     chgres_and_convert_ics: No
     realtime: false
-    gfs_cyc: 4 # run gfs at 0z, 12z
+    STEP_GFS: !timedelta "06:00:00"
     run_gsi: Yes
diff --git a/workflow/cases/dev/fv3q2fy19retro5-GFS@C768_ENKF@384+80MEM.yaml b/workflow/cases/dev/fv3q2fy19retro5-GFS@C768_ENKF@384+80MEM.yaml
index 3ba368393e..46a5a72e9c 100644
--- a/workflow/cases/dev/fv3q2fy19retro5-GFS@C768_ENKF@384+80MEM.yaml
+++ b/workflow/cases/dev/fv3q2fy19retro5-GFS@C768_ENKF@384+80MEM.yaml
@@ -172,5 +172,5 @@ case:
     EDATE: 2016-05-31t18:00:00
     chgres_and_convert_ics: No
     realtime: false
-    gfs_cyc: 4 # run gfs at 0z, 12z
+    STEP_GFS: !timedelta "06:00:00"
     run_gsi: Yes
diff --git a/workflow/cases/dev/fv3q2fy19retro5-GFS@C768_ENKF@384+80MEM_fixed.yaml b/workflow/cases/dev/fv3q2fy19retro5-GFS@C768_ENKF@384+80MEM_fixed.yaml
index 7783972108..5110e6d35d 100644
--- a/workflow/cases/dev/fv3q2fy19retro5-GFS@C768_ENKF@384+80MEM_fixed.yaml
+++ b/workflow/cases/dev/fv3q2fy19retro5-GFS@C768_ENKF@384+80MEM_fixed.yaml
@@ -186,5 +186,5 @@ case:
     EDATE: 2016-02-14t12:00:00
     chgres_and_convert_ics: No
     realtime: false
-    gfs_cyc: 4 # run gfs at 0z, 12z
+    STEP_GFS: !timedelta "06:00:00"
     run_gsi: Yes
diff --git a/workflow/cases/dev/fv3q2fy19retro5-GFS@C768_ENKF@384+80MEM_whatever.yaml b/workflow/cases/dev/fv3q2fy19retro5-GFS@C768_ENKF@384+80MEM_whatever.yaml
index 32964f0caf..baba21188e 100644
--- a/workflow/cases/dev/fv3q2fy19retro5-GFS@C768_ENKF@384+80MEM_whatever.yaml
+++ b/workflow/cases/dev/fv3q2fy19retro5-GFS@C768_ENKF@384+80MEM_whatever.yaml
@@ -186,5 +186,5 @@ case:
     EDATE: 2016-02-14t12:00:00
     chgres_and_convert_ics: No
     realtime: false
-    gfs_cyc: 4 # run gfs at 0z, 12z
+    STEP_GFS: !timedelta "06:00:00"
     run_gsi: Yes
diff --git a/workflow/cases/dev/fv3q2fy19retro5-GFS@C768_ff_fixed.yaml b/workflow/cases/dev/fv3q2fy19retro5-GFS@C768_ff_fixed.yaml
index 59a6780d4e..ff649c4940 100644
--- a/workflow/cases/dev/fv3q2fy19retro5-GFS@C768_ff_fixed.yaml
+++ b/workflow/cases/dev/fv3q2fy19retro5-GFS@C768_ff_fixed.yaml
@@ -95,5 +95,6 @@ case:
     EDATE: 2016-02-14t12:00:00
     chgres_and_convert_ics: No
     realtime: false
-    gfs_cyc: 4 # run gfs at 0z, 12z
+    STEP_GFS: !timedelta "06:00:00"
+    STEP_DA: !timedelta "00:00:00"
     run_gsi: No
diff --git a/workflow/cases/dev/gaea-test.yaml b/workflow/cases/dev/gaea-test.yaml
index f59cb6275f..323f51472a 100644
--- a/workflow/cases/dev/gaea-test.yaml
+++ b/workflow/cases/dev/gaea-test.yaml
@@ -21,5 +21,5 @@ case:
     SDATE: 2015-11-26t00:00:00
     EDATE: 2015-11-26t00:00:00
     realtime: false
-    gfs_cyc: 4 # run gfs four cycles a day
+    STEP_GFS: !timedelta "06:00:00"
     run_gsi: No # disable data assimilation
diff --git a/workflow/cases/dev/lowrsecf@C384.yaml b/workflow/cases/dev/lowrsecf@C384.yaml
index 4ee8f3697f..7beb035b03 100644
--- a/workflow/cases/dev/lowrsecf@C384.yaml
+++ b/workflow/cases/dev/lowrsecf@C384.yaml
@@ -31,7 +31,7 @@ case:
     EDATE: 2018-05-31t12:00:00
     chgres_and_convert_ics: No
     REALTIME: true
-    gfs_cyc: 4 # run gfs at 0z, 12z
+    STEP_GFS: !timedelta "06:00:00"
     run_gsi: YES
 
   post:
diff --git a/workflow/cases/dev/merge2dell_baseline.yaml b/workflow/cases/dev/merge2dell_baseline.yaml
index 39641f897e..0a82133dbe 100644
--- a/workflow/cases/dev/merge2dell_baseline.yaml
+++ b/workflow/cases/dev/merge2dell_baseline.yaml
@@ -139,7 +139,7 @@ case:
     EDATE: 2018-11-26t12:00:00
     chgres_and_convert_ics: No
     realtime: true
-    gfs_cyc: 4
+    STEP_GFS: !timedelta "06:00:00"
     run_gsi: Yes
 
   schedvar:
diff --git a/workflow/cases/dev/merge2jet_baseline.yaml b/workflow/cases/dev/merge2jet_baseline.yaml
index 4a4ba71afa..1004738f32 100644
--- a/workflow/cases/dev/merge2jet_baseline.yaml
+++ b/workflow/cases/dev/merge2jet_baseline.yaml
@@ -181,5 +181,5 @@ case:
     EDATE: 2019-05-02t00:00:00
     chgres_and_convert_ics: No
     realtime: false
-    gfs_cyc: 4 # run gfs at 0z, 12z
+    STEP_GFS: !timedelta "06:00:00"
     run_gsi: Yes
diff --git a/workflow/cases/dev/nco.yaml b/workflow/cases/dev/nco.yaml
index 9d1d855acc..8fcb0195fd 100644
--- a/workflow/cases/dev/nco.yaml
+++ b/workflow/cases/dev/nco.yaml
@@ -136,7 +136,7 @@ case:
     EDATE: 2018-09-22t06:00:00
     chgres_and_convert_ics: No
     realtime: true
-    gfs_cyc: 4
+    STEP_GFS: !timedelta "06:00:00"
     run_gsi: Yes
 
   schedvar:
diff --git a/workflow/cases/dev/parallel@768_ENKF@384+80MEM.yaml b/workflow/cases/dev/parallel@768_ENKF@384+80MEM.yaml
index e3eba3ceeb..25e0a76489 100644
--- a/workflow/cases/dev/parallel@768_ENKF@384+80MEM.yaml
+++ b/workflow/cases/dev/parallel@768_ENKF@384+80MEM.yaml
@@ -34,7 +34,7 @@ case:
     IC_CDUMP: gdas # Get initial conditions from 1st cycle from GFS or GDAS
     SDATE: 2018-05-03t00:00:00
     EDATE: 2018-05-03t18:00:00
-    gfs_cyc: 4 # run gfs at 0z, 12z
+    STEP_GFS: !timedelta "06:00:00"
     run_gsi: Yes
     chgres_and_convert_ics: No
 
diff --git a/workflow/cases/dev/realtime-prfv3rt1_GFS@C768_ENKF@384+80MEM-Dell.yaml b/workflow/cases/dev/realtime-prfv3rt1_GFS@C768_ENKF@384+80MEM-Dell.yaml
index 0a170b5df7..6363565a38 100644
--- a/workflow/cases/dev/realtime-prfv3rt1_GFS@C768_ENKF@384+80MEM-Dell.yaml
+++ b/workflow/cases/dev/realtime-prfv3rt1_GFS@C768_ENKF@384+80MEM-Dell.yaml
@@ -119,5 +119,5 @@ case:
     EDATE: 2018-09-09t18:00:00
     chgres_and_convert_ics: No
     realtime: true
-    gfs_cyc: 4 # run gfs at 0z, 12z
+    STEP_GFS: !timedelta "06:00:00"
     run_gsi: Yes
diff --git a/workflow/cases/dev/realtime-prfv3rt1_GFS@C768_ENKF@384+80MEM.yaml b/workflow/cases/dev/realtime-prfv3rt1_GFS@C768_ENKF@384+80MEM.yaml
index b10dceb0ef..b304ba3056 100644
--- a/workflow/cases/dev/realtime-prfv3rt1_GFS@C768_ENKF@384+80MEM.yaml
+++ b/workflow/cases/dev/realtime-prfv3rt1_GFS@C768_ENKF@384+80MEM.yaml
@@ -42,6 +42,6 @@ case:
     EDATE: 2018-06-04t12:00:00
     chgres_and_convert_ics: No
     realtime: true
-    gfs_cyc: 4 # run gfs at 0z, 12z
+    STEP_GFS: !timedelta "06:00:00"
     run_gsi: Yes
 
diff --git a/workflow/cases/free_forecast_case.yaml b/workflow/cases/free_forecast_case.yaml
index 5f4f24c5bb..1e371bcbcb 100644
--- a/workflow/cases/free_forecast_case.yaml
+++ b/workflow/cases/free_forecast_case.yaml
@@ -9,10 +9,11 @@ case:
   settings: 
     SDATE: 2019-05-01t00:00:00
     EDATE: 2019-05-01t06:00:00
+    STEP_GFS: !timedelta "06:00:00"
+    STEP_DA: !timedelta "00:00:00"
 
     DUMP_SUFFIX: "p"
     run_gsi: No
     chgres_and_convert_ics: Yes
-    gfs_cyc: 4 # run gfs every cycle
 
     mom6ic_prepared: .true.
diff --git a/workflow/cases/jet_cycled.yaml b/workflow/cases/jet_cycled.yaml
index c00e9aefd4..c2a9e375c8 100644
--- a/workflow/cases/jet_cycled.yaml
+++ b/workflow/cases/jet_cycled.yaml
@@ -16,4 +16,4 @@ case:
     DUMP_SUFFIX: ""
     run_gsi: Yes
     chgres_and_convert_ics: No
-    gfs_cyc: 4 # run gfs every cycle
+    STEP_GFS: !timedelta "06:00:00"
diff --git a/workflow/cases/jet_free_forecast.yaml b/workflow/cases/jet_free_forecast.yaml
index 80fb80fc8e..7751d03f0d 100644
--- a/workflow/cases/jet_free_forecast.yaml
+++ b/workflow/cases/jet_free_forecast.yaml
@@ -14,11 +14,12 @@ case:
   settings: 
     SDATE: 2019-05-01t00:00:00
     EDATE: 2019-05-01t00:00:00
+    STEP_GFS: !timedelta "06:00:00"
+    STEP_DA: !timedelta "00:00:00"
 
     DUMP_SUFFIX: "p"
     run_gsi: No
     chgres_and_convert_ics: Yes
-    gfs_cyc: 4 # run gfs every cycle
 
   suite_overrides: !FirstTrue
     - when: !calc (doc.platform.name=="JET")
diff --git a/workflow/cases/manual_mode.yaml b/workflow/cases/manual_mode.yaml
index eb216fefd2..e39284265f 100644
--- a/workflow/cases/manual_mode.yaml
+++ b/workflow/cases/manual_mode.yaml
@@ -92,7 +92,7 @@ case:
     DUMP_SUFFIX: "p"
     run_gsi: Yes
     chgres_and_convert_ics: No
-    gfs_cyc: 4 # run gfs every cycle
+    STEP_GFS: !timedelta "06:00:00"
 
   downstream: &downstream
     DO_POST_PROCESSING: NO
diff --git a/workflow/cases/prototype6.yaml b/workflow/cases/prototype6.yaml
index 3b6c7a639f..922503d661 100644
--- a/workflow/cases/prototype6.yaml
+++ b/workflow/cases/prototype6.yaml
@@ -5,6 +5,8 @@ case:
   settings: 
     SDATE: 2013-04-01t00:00:00
     EDATE: 2013-04-01t00:00:00
+    STEP_GFS: !timedelta "24:00:00"
+    STEP_DA: !timedelta "00:00:00"
 
     onestep: .true.
     cplmode: nems_frac
diff --git a/workflow/cases/public_release_v1/AtmRiv_2016021000_GFS@C192.yaml b/workflow/cases/public_release_v1/AtmRiv_2016021000_GFS@C192.yaml
index ba69708cdf..b0d955bffa 100644
--- a/workflow/cases/public_release_v1/AtmRiv_2016021000_GFS@C192.yaml
+++ b/workflow/cases/public_release_v1/AtmRiv_2016021000_GFS@C192.yaml
@@ -17,4 +17,4 @@ case:
     IC_CDUMP: gfs
     run_gsi: No
     chgres_and_convert_ics: No
-    gfs_cyc: 4 # run gfs every cycle
+    STEP_GFS: !timedelta "06:00:00"
diff --git a/workflow/cases/public_release_v1/AtmRiv_2016021000_GFS@C384.yaml b/workflow/cases/public_release_v1/AtmRiv_2016021000_GFS@C384.yaml
index d8071f420e..f199502ac4 100644
--- a/workflow/cases/public_release_v1/AtmRiv_2016021000_GFS@C384.yaml
+++ b/workflow/cases/public_release_v1/AtmRiv_2016021000_GFS@C384.yaml
@@ -17,4 +17,4 @@ case:
     IC_CDUMP: gfs
     run_gsi: No
     chgres_and_convert_ics: No
-    gfs_cyc: 4 # run gfs every cycle
+    STEP_GFS: !timedelta "06:00:00"
diff --git a/workflow/cases/public_release_v1/Harvey_2017081712_GFS@C192.yaml b/workflow/cases/public_release_v1/Harvey_2017081712_GFS@C192.yaml
index 7a9b56e8d8..b2a8cbef05 100644
--- a/workflow/cases/public_release_v1/Harvey_2017081712_GFS@C192.yaml
+++ b/workflow/cases/public_release_v1/Harvey_2017081712_GFS@C192.yaml
@@ -19,4 +19,4 @@ case:
     IC_CDUMP: gfs
     run_gsi: No
     chgres_and_convert_ics: No
-    gfs_cyc: 4 # run gfs every cycle
+    STEP_GFS: !timedelta "06:00:00"
diff --git a/workflow/cases/public_release_v1/Harvey_2017081712_GFS@C384-override-stuff-in-case-file.yaml b/workflow/cases/public_release_v1/Harvey_2017081712_GFS@C384-override-stuff-in-case-file.yaml
index 6fbebe28f4..0726a92c3c 100644
--- a/workflow/cases/public_release_v1/Harvey_2017081712_GFS@C384-override-stuff-in-case-file.yaml
+++ b/workflow/cases/public_release_v1/Harvey_2017081712_GFS@C384-override-stuff-in-case-file.yaml
@@ -19,7 +19,7 @@ case:
     IC_CDUMP: gfs
     run_gsi: No
     chgres_and_convert_ics: No
-    gfs_cyc: 4 # run gfs every cycle
+    STEP_GFS: !timedelta "06:00:00"
 
   suite_overrides: !FirstTrue
     - when: !calc (doc.platform.name=="JET")
diff --git a/workflow/cases/public_release_v1/Harvey_2017081712_GFS@C384.yaml b/workflow/cases/public_release_v1/Harvey_2017081712_GFS@C384.yaml
index 2787710cef..4f0303d8e2 100644
--- a/workflow/cases/public_release_v1/Harvey_2017081712_GFS@C384.yaml
+++ b/workflow/cases/public_release_v1/Harvey_2017081712_GFS@C384.yaml
@@ -19,4 +19,4 @@ case:
     IC_CDUMP: gfs
     run_gsi: No
     chgres_and_convert_ics: No
-    gfs_cyc: 4 # run gfs every cycle
+    STEP_GFS: !timedelta "06:00:00"
diff --git a/workflow/cases/public_release_v1/Harvey_2017081712_GFS@C768.yaml b/workflow/cases/public_release_v1/Harvey_2017081712_GFS@C768.yaml
index 3146d4a0cd..f745f228d3 100644
--- a/workflow/cases/public_release_v1/Harvey_2017081712_GFS@C768.yaml
+++ b/workflow/cases/public_release_v1/Harvey_2017081712_GFS@C768.yaml
@@ -19,4 +19,4 @@ case:
     IC_CDUMP: gfs
     run_gsi: No
     chgres_and_convert_ics: No
-    gfs_cyc: 4 # run gfs every cycle
+    STEP_GFS: !timedelta "06:00:00"
diff --git a/workflow/cases/public_release_v1/March_Noreasters_2018022800_GFS@C192.yaml b/workflow/cases/public_release_v1/March_Noreasters_2018022800_GFS@C192.yaml
index e0221886dd..406839e5e1 100644
--- a/workflow/cases/public_release_v1/March_Noreasters_2018022800_GFS@C192.yaml
+++ b/workflow/cases/public_release_v1/March_Noreasters_2018022800_GFS@C192.yaml
@@ -17,4 +17,4 @@ case:
     IC_CDUMP: gfs
     run_gsi: No
     chgres_and_convert_ics: No
-    gfs_cyc: 4 # run gfs every cycle
+    STEP_GFS: !timedelta "06:00:00"
diff --git a/workflow/cases/public_release_v1/March_Noreasters_2018022800_GFS@C384.yaml b/workflow/cases/public_release_v1/March_Noreasters_2018022800_GFS@C384.yaml
index 224b24c2a8..2afee405c5 100644
--- a/workflow/cases/public_release_v1/March_Noreasters_2018022800_GFS@C384.yaml
+++ b/workflow/cases/public_release_v1/March_Noreasters_2018022800_GFS@C384.yaml
@@ -17,4 +17,4 @@ case:
     IC_CDUMP: gfs
     run_gsi: No
     chgres_and_convert_ics: No
-    gfs_cyc: 4 # run gfs every cycle
+    STEP_GFS: !timedelta "06:00:00"
diff --git a/workflow/cases/public_release_v1/March_Noreasters_2018022800_GFS@C768.yaml b/workflow/cases/public_release_v1/March_Noreasters_2018022800_GFS@C768.yaml
index 1a7e6da8e3..6f5a0bf0af 100644
--- a/workflow/cases/public_release_v1/March_Noreasters_2018022800_GFS@C768.yaml
+++ b/workflow/cases/public_release_v1/March_Noreasters_2018022800_GFS@C768.yaml
@@ -17,4 +17,4 @@ case:
     IC_CDUMP: gfs
     run_gsi: No
     chgres_and_convert_ics: No
-    gfs_cyc: 4 # run gfs every cycle
+    STEP_GFS: !timedelta "06:00:00"
diff --git a/workflow/cases/tutorial_cycled.yaml b/workflow/cases/tutorial_cycled.yaml
index f426f45a83..18084941dc 100644
--- a/workflow/cases/tutorial_cycled.yaml
+++ b/workflow/cases/tutorial_cycled.yaml
@@ -17,4 +17,4 @@ case:
     KEEPDATA: Yes
     run_gsi: Yes
     chgres_and_convert_ics: No
-    gfs_cyc: 4 # run gfs every cycle
+    STEP_GFS: !timedelta "06:00:00"
diff --git a/workflow/cases/tutorial_free_forecast.yaml b/workflow/cases/tutorial_free_forecast.yaml
index e187acb506..e38d612945 100644
--- a/workflow/cases/tutorial_free_forecast.yaml
+++ b/workflow/cases/tutorial_free_forecast.yaml
@@ -9,11 +9,12 @@ case:
   settings: 
     SDATE: 2019-05-01t00:00:00
     EDATE: 2019-05-01t06:00:00
+    STEP_GFS: !timedelta "06:00:00"
+    STEP_DA: !timedelta "00:00:00"
 
     DUMP_SUFFIX: "p"
     run_gsi: No
     chgres_and_convert_ics: Yes
-    gfs_cyc: 4 # run gfs every cycle
 
   suite_overrides: !FirstTrue
     - when: !calc (doc.platform.name=="JET")
diff --git a/workflow/config/base.yaml b/workflow/config/base.yaml
index 92c2457857..65bf998f6f 100644
--- a/workflow/config/base.yaml
+++ b/workflow/config/base.yaml
@@ -191,10 +191,7 @@ config_base:
     export FHMIN={doc.output_settings.FHMIN_GDAS}
     export FHMAX={doc.output_settings.FHMAX_GDAS}
     export FHOUT={doc.output_settings.FHOUT_GDAS}
-    
-    # GFS cycle info
-    export gfs_cyc={doc.settings.gfs_cyc} # 0: no GFS cycle, 1: 00Z only, 2: 00Z and 12Z only, 4: all 4 cycles.
-    
+        
     # GFS output and frequency
     export FHMIN_GFS={doc.output_settings.FHMIN_GFS}
     export FHMAX_GFS={doc.output_settings.FHMAX_GFS}
diff --git a/workflow/config/wave.yaml b/workflow/config/wave.yaml
index eeca0651da..732dabedb4 100644
--- a/workflow/config/wave.yaml
+++ b/workflow/config/wave.yaml
@@ -78,12 +78,8 @@ config_wave:
         WAVNCYC=4
         WAVHCYC=6
         FHMAX_WAV_CUR=48 # RTOFS forecasts only out to 8 days
-      elif [ $gfs_cyc -ne 0 ]
-      then
-        FHMAX_WAV_CUR=192 # RTOFS forecasts only out to 8 days
-        WAVHCYC=`expr 24 / $gfs_cyc`
       else
-        WAVHCYC=0
+        WAVHCYC={tools.dt_to_HMS(doc.settings.STEP_GFS).split(':')[0]}
         FHMAX_WAV_CUR=192 # RTOFS forecasts only out to 8 days
       fi
       export FHMAX_WAV_CUR WAVHCYC WAVNCYC
diff --git a/workflow/defaults/settings.yaml b/workflow/defaults/settings.yaml
index f6e52d3742..d954f925d8 100644
--- a/workflow/defaults/settings.yaml
+++ b/workflow/defaults/settings.yaml
@@ -35,7 +35,6 @@ default_settings: &default_settings
   ecflow_virtual_clock: no
   ecflow_hybrid_clock: no
 
-  gfs_cyc: 4
   nems_temp: 'atm'
   nems_temp_cold: 'atm'
   ics_from: opsgfs
@@ -78,6 +77,9 @@ default_settings: &default_settings
   IAUFHRS: 6
   IAU_DELTHRS: 6
 
+  STEP_DA: !timedelta "06:00:00"
+  STEP_GFS: !timedelta "06:00:00"
+
   KEEPDATA: NO
   DUMP_SUFFIX: ""
   run_gsi: No
diff --git a/workflow/layout/cycled_gfs.yaml b/workflow/layout/cycled_gfs.yaml
index 8c39f26769..216060a5e7 100644
--- a/workflow/layout/cycled_gfs.yaml
+++ b/workflow/layout/cycled_gfs.yaml
@@ -334,7 +334,7 @@ suite: !Cycle
   ######################################################################
 
   gfs: !Family
-    Disable: !calc doc.settings.gfs_cyc==0
+    Disable: !calc doc.settings.STEP_GFS == doc.zero_dt
     Complete: !Depend ~ suite.has_cycle('-6:00:00')
     AlarmName: gfs
     RUN: 'gfs'
@@ -731,7 +731,7 @@ suite: !Cycle
 
     jgfs_archive: !Task
       <<: *service_task_template
-      Disable: !calc doc.settings.gfs_cyc == 0
+      Disable: !calc doc.settings.STEP_GFS == doc.zero_dt
       Complete: !Depend ~ suite.has_cycle('-6:00:00')
       AlarmName: gfs
       Trigger: !Depend up.gfs
diff --git a/workflow/layout/free_forecast_gfs.yaml b/workflow/layout/free_forecast_gfs.yaml
index 2d8f64da65..a0102240f4 100644
--- a/workflow/layout/free_forecast_gfs.yaml
+++ b/workflow/layout/free_forecast_gfs.yaml
@@ -12,6 +12,7 @@ suite: !Cycle
     Disable: !calc >-
       doc.settings.get("IC_CDUMP","") and not doc.settings.chgres_and_convert_ics or doc.settings.mom6ic_prepared=='.true.'
 #    RUN: 'gfs'
+    AlarmName: gfs
     jgfs_emc_getics: !Task
       <<: *service_task_template
       RUN: 'gfs'
@@ -50,6 +51,7 @@ suite: !Cycle
   gfs: !Family
 #    AlarmName: gdas                    ##!!"gdas" mean to run every 6 hrs from sdate to edate!!"
     RUN: 'gfs'
+    AlarmName: gfs
     ecflow_def: "edit RUN 'gfs'"
 
     prep: !Family
@@ -223,7 +225,7 @@ suite: !Cycle
 
     jgfs_archive: !Task
       <<: *service_task_template
-      Disable: !calc doc.settings.gfs_cyc == 0
+      Disable: !calc doc.settings.STEP_GFS == doc.zero_dt
       AlarmName: gfs
       Trigger: !Depend up.gfs
       resources: !calc partition.resources.run_arch
@@ -241,6 +243,7 @@ suite: !Cycle
   final: !Task
     <<: *service_task_template
     Disable: !calc not metasched.type=="rocoto"
+    AlarmName: gfs
     resources: !calc partition.resources.run_final
     rocoto_command: /bin/true
     model: gfs # useless but required
diff --git a/workflow/layout/manual_temp.yaml b/workflow/layout/manual_temp.yaml
index 58696fbf71..139a4a54e0 100644
--- a/workflow/layout/manual_temp.yaml
+++ b/workflow/layout/manual_temp.yaml
@@ -243,7 +243,7 @@ suite: !Cycle
   ######################################################################
 
   gfs: !Family
-    Disable: !calc doc.settings.gfs_cyc==0
+    Disable: !calc doc.settings.STEP_GFS == doc.zero_dt
     Complete: !Depend ~ suite.has_cycle('-6:00:00')
     AlarmName: gfs
     RUN: 'gfs'
@@ -503,7 +503,7 @@ suite: !Cycle
 
     jgfs_archive: !Task
       <<: *service_task_template
-      Disable: !calc doc.settings.gfs_cyc == 0
+      Disable: !calc doc.settings.STEP_GFS == doc.zero_dt
       Complete: !Depend ~ suite.has_cycle('-6:00:00')
       AlarmName: gfs
       Trigger: !Depend up.gfs
diff --git a/workflow/layout/nco.yaml b/workflow/layout/nco.yaml
index ad9d82cb11..a2a95d52b8 100644
--- a/workflow/layout/nco.yaml
+++ b/workflow/layout/nco.yaml
@@ -280,7 +280,7 @@ suite: !Cycle
   ######################################################################
 
   gfs: !Family
-    Disable: !calc doc.settings.gfs_cyc==0
+    Disable: !calc doc.settings.STEP_GFS == doc.zero_dt
     Complete: !Depend ~ suite.has_cycle('-6:00:00')
     AlarmName: gfs
     RUN: 'gfs'
diff --git a/workflow/runtime/suite.yaml b/workflow/runtime/suite.yaml
index fd521f081d..17f51ba51f 100644
--- a/workflow/runtime/suite.yaml
+++ b/workflow/runtime/suite.yaml
@@ -2,6 +2,9 @@
 # suites in the workflow/ directory.  Most of these variables are
 # specific to the cycled workflow which is not in this release.
 
+day_dt: !timedelta "24:00:00"
+zero_dt: !timedelta "00:00:00"
+
 # gfs_clock_1 - run GFS only at 0 UTC daily
 gfs_clock_1: !Clock
   start: !calc tools.day_of(suite.Clock.start+suite.Clock.step)
@@ -13,12 +16,12 @@ gfs_clock_2: !Clock
   step: !timedelta "12:00:00"
 
 # gfs_clock_4 - run GFS every cycle
-gfs_clock_4: !Clock
-  start: !FirstTrue
-      - when: !calc doc.places.workflow_file == "layout/free_forecast_gfs.yaml"
-        do: !calc suite.Clock.start
-      - otherwise: !calc suite.Clock.start+suite.Clock.step
-  step: !timedelta "06:00:00"
+# gfs_clock_4: !Clock
+#   start: !FirstTrue
+#       - when: !calc doc.settings.STEP_DA == doc.zero_dt
+#         do: !calc suite.Clock.start
+#       - otherwise: !calc suite.Clock.start+suite.Clock.step
+#   step: !timedelta "06:00:00"
 
 # cycled_suite_alarms - this is used to define which cycles various
 # jobs run in.  In the workflow suite definition, jobs may have an
@@ -39,20 +42,26 @@ cycled_suite_alarms: &cycled_suite_alarms
 
   # gfs - cycles for which the gfs is run
   gfs: !FirstTrue
-    - when: !calc doc.settings.gfs_cyc == 0
+    # No free forecast
+    - when: !calc doc.settings.STEP_GFS == doc.zero_dt
       do: !Clock  # required but ignored because gfs is disabled
         start: !calc suite.Clock.start
         end: !calc suite.Clock.end
         step: !calc suite.Clock.step
-    - when: !calc doc.settings.gfs_cyc == 1
-      do: !calc suite.Clock.for_alarm(doc.gfs_clock_1)
-    - when: !calc doc.settings.gfs_cyc == 2
-      do: !calc suite.Clock.for_alarm(doc.gfs_clock_2)
-    - when: !calc doc.settings.gfs_cyc == 4
-      do: !calc suite.Clock.for_alarm(doc.gfs_clock_4)
-    - otherwise: !error Unknown gfs clock settings {doc.settings.gfs_cyc}
+    - otherwise: !Clock
+        start: !FirstTrue
+          - when: !calc doc.settings.STEP_DA == doc.zero_dt
+            # No DA
+            do: !calc suite.Clock.start
+            # Run one DA-only cycle before starting GFS
+          - otherwise: !calc suite.Clock.start+suite.Clock.step
+        end: !calc suite.Clock.end
+        step: !calc doc.settings.STEP_GFS
 
-  gfs_00_12: !calc suite.Clock.for_alarm(doc.gfs_clock_2)
+  gfs_00_12: !FirstTrue
+    - when: !calc doc.settings.STEP_GFS >= doc.day_dt
+      do: !calc suite.Clock.for_alarm(doc.gfs_clock_1)
+    - otherwise: !calc suite.Clock.for_alarm(doc.gfs_clock_2)
 
 
 # suite_defaults - this is inherited by the actual suite definitions
@@ -60,10 +69,14 @@ cycled_suite_alarms: &cycled_suite_alarms
 suite_defaults: &suite_defaults
   # Clock - the list of cycles to run
   Clock: !Clock
-    # NEED TO FIX FOR LESS FREQUENT GFS
     start: !calc doc.settings.SDATE
     end: !calc doc.settings.EDATE
-    step: !timedelta "6:00:00"
+    step: !FirstTrue
+      - when: !calc doc.settings.STEP_DA == doc.zero_dt
+        # No DA, use GFS step
+        do: !calc doc.settings.STEP_GFS
+        # Use DA step, which might be shorter than GFS step
+      - otherwise: !calc doc.settings.STEP_DA
 
   Overrides:
     allowed: [ 'queue', 'partition', 'resources', 'rocoto_command', 'rocoto_log_path',
diff --git a/workflow/schema/settings.yaml b/workflow/schema/settings.yaml
index 7606d59234..ec2cf23096 100644
--- a/workflow/schema/settings.yaml
+++ b/workflow/schema/settings.yaml
@@ -1,15 +1,4 @@
 settings_schema: !Template &settings_schema
-  gfs_cyc:
-    type: int
-    allowed: [ 0, 1, 2, 4 ]
-    description: |
-      When to run GFS forecast.  Data assimilation is run for every
-      cycle regardless of these values
-        * 0: no GFS cycle
-        * 1: 00Z only
-        * 2: 00Z and 12Z only
-        * 4: all 4 cycles (0, 6, 12, 18 Z)
-
   dev_safeguards:
     type: bool
     description: "Add backup triggers in workflow to handle scheduling delays, such as the forecast finishing any posts start.  Only turn this off for NCO operational deliveries."
@@ -99,6 +88,18 @@ settings_schema: !Template &settings_schema
   EDATE:
     type: datetime
     description: Last cycle to run GDAS.
+
+  STEP_DA:
+    type: timedelta
+    optional: true
+    description: |
+      Cadence to run DA.
+  
+  STEP_GFS:
+    type: timedelta
+    optional: true
+    description: |
+      Cadence to run GFS.
   
   ics_from:
     type: string