diff --git a/.github/workflows/ci_fv3_ccpp_prebuild.yml b/.github/workflows/ci_fv3_ccpp_prebuild.yml
index a32b66b7b..a5c2f8092 100644
--- a/.github/workflows/ci_fv3_ccpp_prebuild.yml
+++ b/.github/workflows/ci_fv3_ccpp_prebuild.yml
@@ -3,12 +3,10 @@ name: CI test to run FV3 ccpp_prebuild step
 on: [push, pull_request]
 
 jobs:
-  build-linux:
+  ccpp-prebuild-FV3:
 
     # The type of runner that the job will run on
-    runs-on: ubuntu-latest
-    strategy:
-      max-parallel: 5
+    runs-on: ubuntu-20.04
 
     steps:
     - name: Checkout current ccpp-physics code
diff --git a/.github/workflows/ci_scm_ccpp_prebuild.yml b/.github/workflows/ci_scm_ccpp_prebuild.yml
index 64fac3cd1..7c9d2300a 100644
--- a/.github/workflows/ci_scm_ccpp_prebuild.yml
+++ b/.github/workflows/ci_scm_ccpp_prebuild.yml
@@ -3,12 +3,10 @@ name: CI test to run SCM ccpp_prebuild step
 on: [push, pull_request]
 
 jobs:
-  build-linux:
+  ccpp-prebuild-SCM:
 
     # The type of runner that the job will run on
-    runs-on: ubuntu-latest
-    strategy:
-      max-parallel: 5
+    runs-on: ubuntu-20.04
 
     steps:
 
diff --git a/physics/progsigma_calc.f90 b/physics/progsigma_calc.f90
index 0b37c30c9..eaa1d3fda 100644
--- a/physics/progsigma_calc.f90
+++ b/physics/progsigma_calc.f90
@@ -54,7 +54,7 @@ subroutine progsigma_calc (im,km,flag_init,flag_restart,           &
       epsilon=1.E-11
       km1=km-1
       betadcu = 2.0
-      betascu = 3.6
+      betascu = 8.0
       invdelt = 1./delt
 
      !Initialization 2D
@@ -210,17 +210,18 @@ subroutine progsigma_calc (im,km,flag_init,flag_restart,           &
       enddo
 
       !Reduce area fraction before coupling back to mass-flux computation. 
-      !This tuning could be addressed in updraft velocity equation instead.
       if(flag_shallow)then
          do i= 1, im
             if(cnvflg(i)) then
                sigmab(i)=sigmab(i)/betascu
+               sigmab(i)=MAX(0.03,sigmab(i))
             endif
          enddo
       else
          do i= 1, im
             if(cnvflg(i)) then
                sigmab(i)=sigmab(i)/betadcu
+               sigmab(i)=MAX(0.01,sigmab(i))
             endif
          enddo
       endif
diff --git a/physics/samfdeepcnv.f b/physics/samfdeepcnv.f
index 4ba887353..2a3c256a9 100644
--- a/physics/samfdeepcnv.f
+++ b/physics/samfdeepcnv.f
@@ -238,7 +238,7 @@ subroutine samfdeepcnv_run (im,km,first_time_step,restart,        &
 !     parameter(cinacrmx=-120.,cinacrmn=-120.)
       parameter(cinacrmx=-120.,cinacrmn=-80.)
       parameter(bet1=1.875,cd1=.506,f1=2.0,gam1=.5)
-      parameter(betaw=.03,dxcrtuf=15.e3)
+      parameter(betaw=.03)
 
 !
 !  local variables and arrays
@@ -2468,8 +2468,10 @@ subroutine samfdeepcnv_run (im,km,first_time_step,restart,        &
 !
       if(progsigma)then
          dxcrtas=30.e3
+         dxcrtuf=10.e3
       else
          dxcrtas=8.e3
+         dxcrtuf=15.e3
       endif
 
 
@@ -3519,9 +3521,13 @@ subroutine samfdeepcnv_run (im,km,first_time_step,restart,        &
             if(k > kb(i) .and. k < ktop(i)) then
               tem = 0.5 * (eta(i,k-1) + eta(i,k)) * xmb(i)
               tem1 = pfld(i,k) * 100. / (rd * t1(i,k))
-              sigmagfm(i) = max(sigmagfm(i), betaw)
-              ptem = tem / (sigmagfm(i) * tem1)
-              qtr(i,k,ntk)=qtr(i,k,ntk)+0.5*sigmagfm(i)*ptem*ptem
+              if(progsigma)then
+                tem2 = sigmab(i)
+              else
+                tem2 = max(sigmagfm(i), betaw)
+              endif
+              ptem = tem / (tem2 * tem1)
+              qtr(i,k,ntk)=qtr(i,k,ntk)+0.5*tem2*ptem*ptem
             endif
           endif
         enddo
@@ -3533,9 +3539,13 @@ subroutine samfdeepcnv_run (im,km,first_time_step,restart,        &
             if(k > 1 .and. k <= jmin(i)) then
               tem = 0.5*edto(i)*(etad(i,k-1)+etad(i,k))*xmb(i)
               tem1 = pfld(i,k) * 100. / (rd * t1(i,k))
-              sigmagfm(i) = max(sigmagfm(i), betaw)
-              ptem = tem / (sigmagfm(i) * tem1)
-              qtr(i,k,ntk)=qtr(i,k,ntk)+0.5*sigmagfm(i)*ptem*ptem
+              if(progsigma)then
+                tem2 = sigmab(i)
+              else
+                tem2 = max(sigmagfm(i), betaw)
+              endif
+              ptem = tem / (tem2 * tem1)
+              qtr(i,k,ntk)=qtr(i,k,ntk)+0.5*tem2*ptem*ptem
             endif
           endif
         enddo
diff --git a/physics/samfshalcnv.f b/physics/samfshalcnv.f
index 1b648c109..645024536 100644
--- a/physics/samfshalcnv.f
+++ b/physics/samfshalcnv.f
@@ -188,7 +188,7 @@ subroutine samfshalcnv_run(im,km,itc,ntc,cliq,cp,cvap,            &
       parameter(cinacrmx=-120.,shevf=2.0)
       parameter(dtmax=10800.,dtmin=600.)
       parameter(bet1=1.875,cd1=.506,f1=2.0,gam1=.5)
-      parameter(betaw=.03,dxcrt=15.e3,dxcrtc0=9.e3)
+      parameter(betaw=.03,dxcrtc0=9.e3)
       parameter(h1=0.33333333)
 !  progsigma
       parameter(dxcrtas=30.e3)
@@ -258,6 +258,12 @@ subroutine samfshalcnv_run(im,km,itc,ntc,cliq,cp,cvap,            &
              cinacrmn=-80.
       endif
 
+      if (progsigma) then
+         dxcrt=10.e3
+      else
+         dxcrt=15.e3
+      endif
+
 c-----------------------------------------------------------------------
       if (.not.hwrf_samfshal) then
 !>  ## Determine whether to perform aerosol transport
@@ -2449,9 +2455,13 @@ subroutine samfshalcnv_run(im,km,itc,ntc,cliq,cp,cvap,            &
             if(k > kb(i) .and. k < ktop(i)) then
               tem = 0.5 * (eta(i,k-1) + eta(i,k)) * xmb(i)
               tem1 = pfld(i,k) * 100. / (rd * t1(i,k))
-              sigmagfm(i) = max(sigmagfm(i), betaw)
-              ptem = tem / (sigmagfm(i) * tem1)
-              qtr(i,k,ntk)=qtr(i,k,ntk)+0.5*sigmagfm(i)*ptem*ptem
+              if(progsigma)then
+                tem2 = sigmab(i)
+              else
+                tem2 = max(sigmagfm(i), betaw)
+              endif
+              ptem = tem / (tem2 * tem1)
+              qtr(i,k,ntk)=qtr(i,k,ntk)+0.5*tem2*ptem*ptem
             endif
           endif
         enddo